The EPA Acting Regional Administrator, Alexis Strauss, signed the following rule on June 15, 2016 and EPA is submitting it for publication in th e Federal Register (FR). While we have taken steps to ensure the accuracy of this version of this rule, it is not the official version. Please refer to the official version in a forthcoming FR publi cation appearing on the Government Printing Office website, http://fdsys.gpo.gov/fdsys/search/home. action, and on www.regulations.gov in Docket Number EPA-R09-OAR-2015-0846. ENVIRONMENTAL PRO TECTION AGENCY 40 CFR Part 52 [EPA-R09-OAR-2015-0846, FRL-YYY] Promulgation of Air Quality Im plementation Plans; Arizona; Regional Haze Federal Implementation Plan; Reconsideration AGENCY : Environmental Protection Agency (EPA). ACTION : Proposed rule. SUMMARY : The Environmental Protection Agency (EPA ) is proposing to re vise provisions of the Arizona Regional Haze Federal Implementation Plan (FIP) applicable to the Phoenix Cement Company (PCC) Clarkdale Plant a nd the CalPortland Cement (CPC) Rillito Plant. In response to requests for reconsideration from the plants’ owners, we propose to replace the c ontrol technology optimization requirements for nitrogen oxides (NO X ) applicable to Kiln 4 at the Clarkdale Plant and Kiln 4 at the Rillito Plant with a series of revised recordkeeping and reporting requirements. We are seeking comment on this proposed action. DATES : Written comments must be submitted on or before [ Insert date 45 days after the date of publication in the Federal Register ]. Requests for a public hearin g must be received on or before [ Insert date 15 days after the date of publication in the Federal Register ]. ADDRESSES : Submit your comments, identified by Docket ID No. EPA-R09-OAR-2015-0846 at http://www.regulations.gov, or via email to limaye.vijay@epa.gov. For comments submitted at Regulations.gov, follow the online instructions for submitting comments. Once submitted, comments cannot be edited or re moved from Regulations.gov. For either manner of submission,This document is a prepublication version signed by EPA Acting Regional Administrator Alexis Strauss on June 15, 2016. We have taken steps to en sure the accuracy of this version, but it is not the official version.

Page 2 of 22 the EPA may publish any comment received to its public docket. Do not su bmit electronically any information you consider to be Confidential Bu siness 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 comme nt 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 additiona l submission methods, pleas e contact the person identified in the “FOR FURTHER INFORMATI ON CONTACT” section. For the full EPA public comment policy, information about CBI or mu ltimedia submissions, and general guidance on making effective comments, please visit http ://www2.epa.gov/dockets/co mmenting-epa-dockets. FOR FURTHER INFORMATION CONTACT : Vijay Limaye, U.S. EPA, Region 9, Planning Office, Air Division, Air-2, 75 Ha wthorne Street, San Francisco, CA 94105. Vijay Limaye can be reached at telephone number (415) 972-3086 and via electronic mail at limaye.vijay@epa.gov. SUPPLEMENTARY INFORMATION : Throughout this document, “we,” “us,” and “our” refer to the EPA. Table of Contents I. General Information II. Background III. Proposed FIP Revision for the PCC Clar kdale Plant and the CPC Rillito Plant IV. The EPA’s Proposed Action V. Statutory and Executive Order Reviews I. General Information

A. DefinitionsThis document is a prepublication version signed by EPA Acting Regional Administrator Alexis Strauss on June 15, 2016. We have taken steps to en sure the accuracy of this version, but it is not the official version.

Page 3 of 22 For the purpose of this document, we are givi ng meaning to certain words or initials as follows:

 The words or initials Act or CAA mean or refer to the Clean Air Act, unless the context indicates otherwise.

 The initials ADEQ mean or refer to the Arizona De partment of Environmental Quality.

 The words Arizona and State mean the State of Arizona.

 The initials BART mean or refer to Best Available Retrofit Technology.

 The term Class I area refers to a mandatory Class I Federal area. 1

 The initials CBI mean or refer to Confidential Business Information.

 The initials CPC mean or refer to CalPortland Cement.

 The words EPA , we , us or our mean or refer to the United States Environmental Protection Agency.

 The initials FIP mean or refer to Federal Implementation Plan.

 The initials NO X mean or refer to nitrogen oxides.

 The initials PCC mean or refer to Phoenix Cement Company

 The initials SIP mean or refer to State Implementation Plan.

 The initials SNCR mean or refer to select ive non-catalytic reduction.

 The initials SRPMIC mean or refer to Salt River Pima-Maricopa Indian Community. B. Docket The proposed action relies on documents, informati on, and data that are listed in the index

1 Although states and tribes may designate as Class I add itional areas which they consider to have visibility as an important value, the requirements of the visibility prog ram set forth in section 169A of the CAA apply only to “mandatory Class I Federal areas.”This document is a prepublication version signed by EPA Acting Regional Administrator Alexis Strauss on June 15, 2016. We have taken steps to en sure the accuracy of this version, but it is not the official version.

Page 4 of 22 on http://www.regulations.gov under docket number EPA-R09-OAR-2015-0846. Although listed in the index, some information is not publicly ava ilable (e.g., CBI). Certain other material, such as copyrighted material, is publicly available only in hard copy form. Publicly available docket materials are available either electronically at http://www.regulations.gov or in hard copy at the Planning Office of the Air Divi sion, AIR-2, EPA Region 9, 75 Hawt horne Street, San Francisco, CA 94105. The EPA requests that you contact th e individual listed in the FOR FURTHER INFORMATION CONTACT section to view the hard copy of the docket. You may view the hard copy of the docket Monday through Friday, 9-5:00 PDT, excluding Federal holidays.

C. Public Hearings If anyone contacts the EPA by [ Insert date 15 days from publication in the Federal Register ] requesting to speak at a public hearing, the EPA will schedule a public hearing and announce the hearing in the Federal Register . Contact Vijay Limaye at (415) 972-3086 or at limaye.vijay@epa.gov to request a hearing or to determine if a hearing will be held. II. Background

A. Summary of Statutory and Regulatory Requirements This section provides a brief overview of the requirements of the Clean Air Act (CAA) and the EPA’s Regional Haze Rule, as they apply to this particular action. Please refer to our previous rulemakings on the Arizona Regional Haze Stat e Implementation Plan (SIP) for additional background regarding the vi sibility protection provisions of the CAA and the Regional Haze Rule. 2 Congress created a program for protecting visi bility in the nation's national parks and wilderness areas in section 169A of the 1977 Amen dments to the CAA. This section of the CAA

2 77 FR 42834, 42837-42 839 (July 20, 2012), (Arizona Regional Haze “Phase 1” Rule) 77 FR 75704, 7 5709-75712 (December 21, 2012), (Arizona Regi onal Haze “Phase 2” Rule).This document is a prepublication version signed by EPA Acting Regional Administrator Alexis Strauss on June 15, 2016. We have taken steps to en sure the accuracy of this version, but it is not the official version.

Page 5 of 22 establishes as a national goal the “prevention of any future, and the remedying of any existing, impairment of visibility in mandatory Class I Federal areas which impairment results from manmade air pollution.” 3 Specifically, section 169A(b)(2)(A) of th e CAA requires states to revise their SIPs to contain such measures as may be nece ssary to make reasonabl e progress towards the natural visibility goal. In the 1990 CAA Amendments, Congres s amended the visibility provisions in the CAA to focus attention on the problem of regional haze, which is visibility impairment produced by a multitude of sources and activ ities located across a broad geographic area. 4 We promulgated the Regional Haze Rule in 1999, which requires st ates to develop and implement SIPs to ensure reasonable progress toward improv ing visibility in mandatory Class I Federal areas 5 by reducing emissions that cause or contribute to regional haze. 6 B. History of FIP Requirements The Arizona Department of Environmental Quality (ADEQ) submitted a Regional Haze SIP to the EPA on February 28, 2011. The EPA prom ulgated two final rules approving in part and disapproving in part the Arizona Regional Haze SI P. The first final rule addressed the State’s BART determinations for three power plants (Ap ache Generating Station, Cholla Power Plant, and Coronado Generating Station). 7 The second final rule, which addressed the remaining elements of the Arizona Regional Haze SIP, included our disa pproval of the State’s an alysis of reasonable progress measures for point sources of NO X . 8

3 42 U.S.C. 7491(a)(1). 4 See CAA section 169B, 42 U.S.C. 7492. 5 Areas designated as mandatory Class I Federal areas consist of national parks exceeding 6000 acres, wilderness areas, and national memorial parks exceeding 5000 acres, and a ll international parks that we re in existence on August 7, 1977. 42 U.S.C. 7472(a). When we use the term “Class I area” in this action, we mean a “mandatory Class I Federal area.” 6 See generally 40 CFR 51.308. 7 77 FR 72512 (D ecember 5, 2012). 8 78 FR 46142 (July 30, 2013).This document is a prepublication version signed by EPA Acting Regional Administrator Alexis Strauss on June 15, 2016. We have taken steps to en sure the accuracy of this version, but it is not the official version.

Page 6 of 22 In a third final rule, the EP A promulgated a FIP addressi ng the requirements of the Regional Haze Rule and interstate visibility transp ort for the remainder of the disapproved portions of Arizona's Regional Haze SIP. 9 Among other things, the Arizona Regional Haze FIP includes requirements for NO X emission controls applicable to PCC Clarkdale Plant Kiln 4 and CPC Rillito Plant Kiln 4 under the reasonable progress requirem ents of the Regional Haze Rule. In particular, the EPA established two alternative emission limits for NO X on Kiln 4 of the Clarkdale Plant: a 2.12 lb/ton limit or an 810 tons/year limit. The lb/t on limit equates to the installation of SNCR, based on a 50 percent control effi ciency, while the ton/year limit could be met either by installing SNCR or by maintaining recent producti on levels. We set an emission limit for NO X at the Rillito Plant of 3.46 lb/ton, based on a 35 percent control efficiency. The FIP also includes monitoring, recordkeeping, and reporting requirements and a complian ce deadline for the final NO X emission limits of December 31, 2018. Finally, in response to comments alleging that SNCR control efficiencies of 50 percent for Kiln 4 at the Clarkd ale Plant and 35 percent for Kiln 4 at the Rillito Plant were unsupported and that SNCR was capable of achieving higher control efficiencies, we included in the final FIP requirements for c ontrol technology demonstration (“optimization requirements”) for the SNCR systems at both plants, which entail the collection of data that then could be used to determine if a higher control efficiency would be achievable.

C. Petitions for Reconsideration and Stay PCC and CPC each submitted a petition to the EPA on November 3, 2014, seeking administrative reconsideration and a partial stay of the final FIP under CAA section 307(d)(7)(B) and the Administrative Procedure Act. 10 In their petitions, both companies raised multiple

9 79 FR 52420 (September 3, 2014)(Arizona Regional Haze “Phase 3” Rule). 10 Letter from Verle C. Martz, PCC, to Regina McCarthy, EPA (November 3, 2014); Letter from Jay Grady, CPC, to Regina McCarthy, EPA (November 3, 2014).This document is a prepublication version signed by EPA Acting Regional Administrator Alexis Strauss on June 15, 2016. We have taken steps to en sure the accuracy of this version, but it is not the official version.

Page 7 of 22 objections to the optimization requirements in the FIP. CPC asserted that the requirements were burdensome, expensive, and unnecessary, given th at CPC had already “evaluated fuels, fuel fineness, and the other characteris tics listed in the Optimization Protocol” as part of its effort to reduce energy usage. 11 PCC stated that the requirements “would be burdensome to implement” and “would substantially interfere with the ce ment manufacturing operations” at the Clarkdale Plant. 12 PCC further asserted that requirements w ould harm the Salt River Pima-Maricopa Indian Community (SRPMIC), which relies on revenue from the Clarkdale Plant. 13 The EPA sent letters to PCC and CPC on January 16, 2015 and January 27, 2015, respectively, granti ng reconsideration of the optimization requirements pursuant to CAA section 307(d)(7)(B). 14 Today’s notice of proposed rulemaking constitutes the EPA’s proposed action on reconsideration. III. Proposed FIP Revision for the PCC Cl arkdale Plant and the CPC Rillito Plant

A. The EPA’s Evaluation of Control T echnology Demonstration Requirements In light of the objections to the control tec hnology demonstration requirements raised by CPC and PCC, we have re-evaluated the necessity of these requirements for the Rillito and Clarkdale plants. As explained in our September 3, 2014 final rule, the two objectives of the control technology demonstration requirement s are to ensure that the NO X emission limits for the cement kilns are appropriate and to ensure that perf ormance of the SNCR systems at the kilns is

11 Letter from Jay Grady, CPC, to Regina McCarthy, EPA (November 3, 2014), attachment entitled “Petition of CalPortland Company for Partial Reconsideration and Request for Administrative Stay of EPA Final Rule, Promulgation of Air Quality Implementation Plans; Ariz ona; Regional Haze and Interstate Visibility Transport Federal Implementation Plan Published at 79 Fed. Reg. 52420” at 4. 12 Letter from Verle C. Martz, PCC, to Regina McCarthy, EPA (November 3, 2014) at 2. 13 We note that while the Clarkdale Plant is tribally owned, it is not located on tribal land. It is subject to State jurisdiction and is regulated by ADEQ. 14 Letter from Jared Blumenfeld, EPA, to Verle C. Martz, PCC (January 16, 2015); Letter from Jared Blumenfeld, EPA, to Jay Grady, CPC (January 27, 2015).This document is a prepublication version signed by EPA Acting Regional Administrator Alexis Strauss on June 15, 2016. We have taken steps to en sure the accuracy of this version, but it is not the official version.

Page 8 of 22 optimized. 15 In developing this proposed action on r econsideration, we have considered whether it is possible to achieve these objectives through other means. In particular, we have identified additional information regard ing SNCR performance and NO X emission rates from SNCRequipped cement kilns that supports the existing NOx emission limits for the Rillito and Clarkdale kilns in the FIP. As a result, we no longer consid er it necessary for PCC and CPC to adhere to the relatively detailed and prescrip tive control technology de monstration requirements in the existing FIP. We are therefore proposing to remove the c ontrol technology demonstration requirements and are proposing a set of revised recordkeeping and reporting requirements that will require CPC and PCC to report information regarding SNCR system design and optimization in a less prescribed

manner. 1. Rillito Plant Kiln 4 The EPA is proposing to remove the contro l technology demonstration requirements for Kiln 4 (the preheater/precalciner kiln ) at the CPC Rillito Plant based on NO X emission data from a similar kiln at another CPC facility, the Mojave Plant. On December 15, 2011, CPC entered into a consent decree with the EPA, which requir ed the installation of SNCR on the single preheater/precalciner kiln at the Mojave Plan t. As part of the consent decree, this preheater/precalciner kiln at the Mojave Plan t was subject to certain control technology demonstration requirements. Commonly referred to as a “test and set” a pproach, these consent decree provisions required CPC to design and inst all an SNCR system, develop a protocol for optimizing its operation, record NO X emission data over a long-termperiod, and propose a sitespecific emission limit based on those results.

15 See 79 FR 52455-52456, 52462.This document is a prepublication version signed by EPA Acting Regional Administrator Alexis Strauss on June 15, 2016. We have taken steps to en sure the accuracy of this version, but it is not the official version.

Page 9 of 22 As noted in the response to comment s in our September 3, 2014 final rule, 16 CPC submitted comments noting certain site-specific aspect s of the Rillito Kiln 4 that indicated it could not achieve the same level of SNCR control efficiency as the Mojave Plant’s kiln. 17 In our final rule, we indicated that we found this analysis of Rillito Kiln 4 to be generally reasonable, and based the final 3.46 lb/ton NO X limit on the 35% SNCR control efficiency estimated by CPC. While preparing our final rule, we examined the data used to develop the Mojave Plant optimization protocol, which indicated that th e SNCR system at the Mojave Plant could be expected to achieve in the range of 30-60% cont rol efficiency. Given that this range included control efficiencies that were significantly highe r than the efficiency on which the final limit for Rillito Kiln 4 was based, these initial data from Mojave suggested that inclusion of control technology demonstration requirements in the final ru le would be appropriate in order to allow us to evaluate whether or not Rillito Kiln 4 could be further op timized to achieve a more stringent control efficiency. Following promulgation of the final rule on September 3, 2014, the Mojave Plant completed a 270-day demonstrati on period of its SNCR system. 18 Based upon the consent decree methodology, the emission data from the demonstration period indicate a NO X limit for the Mojave Plant kiln of 2.70 lb /ton on a rolling 30-kiln-ope rating-day basis. This is approximately equal to an SNCR control efficiency of 40% , which is on the lower end of the range that was suggested by the optimization protocol. 19

16 79 FR 52462-52463. 17 Letter from Jay Grady, CPC, to Thomas Webb, EPA (March 31, 2014) and Exhibit 1, “Evaluation of EPA’s Reasonable Progress Analysis for Kiln 4 at CalPortla nd Company’s Rillito Cement Plant.” To summarize, CPC asserted that an SNCR system on Rillito Kiln 4 would opera te with less efficient exhaust mixing, lower ammonia injection temperatures, and lower oxygen concentrati ons, all of which would reduce SNCR effectiveness. 18 The demonstration period extended from February to November 2014, and was submitted to the EPA in early 2015. See spreadsheet “Mojave Demonstration Period Data.xlsx.” 19 Based on a baseline pre-SNCR NO X emission rate of 4.5 lb/ton. This value was based on the highest of recentThis document is a prepublication version signed by EPA Acting Regional Administrator Alexis Strauss on June 15, 2016. We have taken steps to en sure the accuracy of this version, but it is not the official version.

Page 10 of 22 Given that the SNCR system on the Rillito Kiln 4 can be expected to underperform the Mojave Plant, and that the Mojave demonstration period data resulted in a limit reflecting an SNCR control efficiency of only 40%, 20 we find that the final NO X limit for Rillito Kiln 4, which is based on a 35% control efficiency, is adequately supported by the available data. Accordingly, we no longer consider it necessary for CPC to meet th e relatively detailed a nd prescriptive control technology demonstration requirements in the existi ng FIP. We are therefore proposing to remove the control technology demonstration requirements fr om the FIP. As explained in section III.B below, we are proposing to replace the control technology demonstration re quirements with a set of revised recordkeeping and reporting require ments that will require CPC to report similar information regarding SNCR system design and optim ization, but in a less prescribed manner.
2. Clarkdale Plant Kiln 4 The EPA is also proposing to remove the c ontrol technology demons tration requirements for Kiln 4 (the preheater/precalciner kiln ) at the PCC Clarkdale Plant based on the NO X emission data from the preheater/precalciner kiln at the CP C Mojave Plant. In the case of Clarkdale Kiln 4, the relatively recent co nstruction of the kiln 21 and its generally lower pre-control NO X emission

rates 22 indicate that an SNCR system on Clarkdale Kiln 4 would be able to achieve a lower NO X emission limit than the Mojave Plant. The final NO X limit promulgated for Clarkdale Kiln 4 is 2.12 lb/ton, on a rolling 30-kiln-opera ting-day basis, which is based on a 50% control efficiency. As noted in the previous section, the emission da ta from the Mojave Plant demonstration period

source test results, as summarized in spreadsh eet “CPC annual revised emissions chart.xlsx” 20 We note that the difference between the two limits, 2.70 lb/ton and 3.46 lb/ton, is larger than what would be suggested by a mere 5% difference in co ntrol efficiencies (i.e., between 40% and 35%). This is primarily due to the different baseline emission rates of the two kilns, with the Rillito kiln having a much higher baseline NO X emission rate than Mojave, in addition to a lower SNCR effectiveness. 21 Clarkdale Kiln 4 was constructed in 2002. The Mojave preheater/precalciner kiln was constructed in 1981. 22 For purposes of the reasonable progress de termination, Clarkdale Kiln 4 has a baseline NO X emission rate of 3.25 lb/ton. The Mojave baseline emission rate was 4.50 lb/ton.This document is a prepublication version signed by EPA Acting Regional Administrator Alexis Strauss on June 15, 2016. We have taken steps to en sure the accuracy of this version, but it is not the official version.

Page 11 of 22 indicated a final NO X limit of 2.70 lb/ton on a rolling 30 kiln operating day basis, which corresponds to an SNCR control efficiency of approximately 40%. Given that a more stringent emission limit and SNCR control efficiency was not demonstrated at th e Mojave Plant, we consider the final limit for Clarkdale Kiln 4 to be sufficiently stringe nt and supported by the available data. Accordingly, we no longer consider it necessary for PCC to adhere to the relatively detailed and prescriptive control technology demons tration requirements in the existing FIP. We are therefore proposing to remove the control technology demonstration requirements. As explained in section III.B below, we are proposin g to replace the control technology demonstration requirements with a set of revised recordkeeping and reporting requirements that will require PCC to report similar information regarding SNCR sy stem design and optimi zation, but in a less prescribed manner.

B. Revised Recordkeeping and Reporting Requirements

As described in III.A above, we no longer consider it necessary for CPC and PCC to comply with the relatively prescriptive and de tailed optimization requireme nts established in our September 4, 2014 final rule. We are therefore proposing to remove the control technology demonstration requirements in the FIP for the Clarkdale and Rillito Plants, and instead are proposing certain revisions to the reporting and recordkeepi ng requirements that involve documentation and submittal of certain design an d optimization activities that are part of a typical SNCR system installation. Specifically, we propose to require PCC and CPC to submit a report of SNCR design prior to commencing constr uction of the ammonia injection system at Clarkdale Kiln 4 and Rillito Kiln 4 respectivel y, including information regarding reagent type, locations selected for reagent injection, reagent injection rate, equipment arrangement, and kiln characteristics. In addition, PCC and CPC w ould be required to submit a report of SNCRThis document is a prepublication version signed by EPA Acting Regional Administrator Alexis Strauss on June 15, 2016. We have taken steps to en sure the accuracy of this version, but it is not the official version.

Page 12 of 22 debugging and process improvement activities, including a description of each process adjustment performed on the SNCR system, a disc ussion of whether the ad justment affected the
NO X emission rate, a description of the range ove r which the adjustment was examined, and a discussion of how the adjustment will be reflec ted or accounted for in kiln operating practices. PCC and CPC would also be required to submit a ny CEMS data and kiln operating data collected during the debugging and process improvement activ ities. These proposed revisions are detailed in the proposed regulatory text at 40 CFR 52.145(k).

C. Non-interference with Applicable Requirements The CAA requires that any revision to an im plementation plan shall not be approved by the Administrator if the revision would interfer e with any applicable requirement concerning attainment and reasonable further progress or any other applicable re quirement of the CAA. 23 Today’s proposed revisions to the Arizona Regi onal Haze FIP would not affect any applicable requirements of the CAA because they would not alter the amount or timing of emission reductions from the Clarkdale Plant or the Rillito Plant. In particular, the proposed replacement of the control technology dem onstration requirements with a series of recordkeeping and reporting requirements would not alter any of th e applicable emission limitations, compliance determination methodologies, or compliance deadlines. Therefore, we propose to find that these revisions would comply with CAA section 110(l). IV. The EPA's Proposed Action For the reasons described above, the EPA propos es to revise the Ar izona Regional Haze FIP to replace the control technology optimizat ion requirements at the PCC Clarkdale Plant and the CPC Rillito Plant with a series of recordk eeping and reporting requirements. Please note that

23 CAA Section 110(l), 42 U.S.C. 7410(l).This document is a prepublication version signed by EPA Acting Regional Administrator Alexis Strauss on June 15, 2016. We have taken steps to en sure the accuracy of this version, but it is not the official version.

Page 13 of 22 while the proposed regulatory text includes the entirety of 40 CFR 52.145(k), we are only proposing to revise those elements of the regu lation related to optimization requirements. V. Statutory and Executive Order Reviews Additional information about these statut es and Executive Orders can be found at http://www2.epa.gov/laws-regulati ons/laws-and-executive-orders

.

A. Executive Order 12866: Regulatory Planning and Review and Executive Order 13563: Improving Regulation and Regulatory Review This proposed action is not a “significant regulatory action” under the terms of Executive Order 12866 (58 FR 51735, October 4, 1993) and is therefore not subject to review under Executive Orders 12866 and 13563 (76 FR 3821, Janua ry 21, 2011). This proposed rule applies to only one facility and is therefore not a rule of gene ral applicability.

B. Paperwork Reduction Act (PRA) This action does not impose an information co llection burden under th e provisions of the PRA, 44 U.S.C. 3501 et seq. Burden is defined at 5 CFR 1320.3(b).

C. Regulatory Flexibility Act (RFA) I certify that this action will not have a si gnificant economic impact on a substantial number of small entities under the RFA. This action will not impose any requirements on small entities. For purposes of assessing the impacts of today’s pro posed rule on small entities, small entity is defined as: (1) A small business as defined by the Small Business Administration’s (SBA) regulations at 13 CFR 121.201; (2) a small governmental jurisd iction that is a government of a city, county, town, school district or spec ial district with a popul ation of less than 50,000; and (3) a small organization that is any not-for-p rofit enterprise which is independently owned and operated and is not dominant in its field. Pursuant to 13 CFR 121.201, footnote 1, a firm isThis document is a prepublication version signed by EPA Acting Regional Administrator Alexis Strauss on June 15, 2016. We have taken steps to en sure the accuracy of this version, but it is not the official version.

Page 14 of 22 small if it is in NAICS 327310 (cement manufacturi ng) and the concern and its affiliates have no more than 750 employees. CPC is owned by Taiheiyo Cement Corporation, which has more than 750 employees. 24 PCC is a division of SRPMIC. 25 For the purposes of the RFA, tribal governments are not considered small governments. 5 U.S.C. 601(5). Therefore SRPMIC is not a small entity.

D. Unfunded Mandates Reform Act (UMRA) This action does not contain an unfunded ma ndate of $100 million or more as described in UMRA, 2 U.S.C. 1531–1538. This action may significantly or uniquely affect small governments. As a tribal government, SRPMIC is considered a “small government” under UMRA. See 2 U.S.C. 658(11) and (13). The EPA consulted with SRPMIC concerning the regulatory requirements that might significantly or uniquely affect it. 26

E. Executive Order 13132: Federalism This action does not have federalism implica tions. It will not have substantial direct effects on the states, on the relationship between th e national government and the states, or in the distribution of power and responsib ilities among the various levels of government, as specified in Executive Order 13132.

F. Executive Order 13175: Consultation and Coor dination with Indian Tribal Governments This action has tribal implications. Howeve r, it will neither impose substantial direct compliance costs on federally recognized tribal governments, nor preempt tribal law. This proposed action, if finalized, would eliminate the SNCR optimization requirements that currently

24 See Taiheiyo Cement Corp. Annual Report 2015, pages 1 and 36. 25 Letter from Diane Enos, President, SRPMIC, to Jared Blumenfield, Regional Administrator, EPA Region 9 (December 20, 2012). 26 See Summary of Consultation with SRPMIC Regarding Regional Haze FIP Reconsideration.This document is a prepublication version signed by EPA Acting Regional Administrator Alexis Strauss on June 15, 2016. We have taken steps to en sure the accuracy of this version, but it is not the official version.

Page 15 of 22 apply to the PCC Clarkdale Plan t. The profits from the Clarkd ale Plant are used to provide government services to SRPMIC's members. The EPA consulted with tribal official s under the EPA Policy on Consultation and Coordination with Indian Tribes early in the pr ocess of developing this regulation to permit them to have meaningful and timely input into its development. 27

G. Executive Order 13045: Protection of Childre n 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 childre n, 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 concern an environmental health risk or safety ris k.

H. Executive Order 13211: Actions Concerning Regul ations 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) This rulemaking does not invol ve technical standards. J. Executive Order 12898: Federal Actions to Address Environmental Justice in Minority Populations and Low-Income Populations The EPA has determined that this proposed rule will not have disproportionately high and adverse human health or environmental effects on minority or low-income populations because it

27 Id.This document is a prepublication version signed by EPA Acting Regional Administrator Alexis Strauss on June 15, 2016. We have taken steps to en sure the accuracy of this version, but it is not the official version.

Page 16 of 22 does not change the level of environmenta l protection for any affected populations.

K. Determination Under Section 307(d) Pursuant to CAA section 307(d)(1)(B), the EPA proposes to determine that this action is subject to the provisions of sec tion 307(d). Section 307(d) establ ishes procedural requirements specific to certain rulemaking ac tions under the CAA. Pursuant to CAA section 307(d)(1)(B), the revision of the provisions of the Arizona Regi onal Haze FIP that apply to the PCC Clarkdale Plant and the CPC Rillito Plant is subject to the requirements of CAA section 307(d), as it constitutes a revision to a FIP under CAA section 110(c). List of Subjects in 40 CFR Part 52 Environmental protection, Air po llution control, Nitrogen oxides , Reporting and recordkeeping requirements, Visibility. AUTHORITY : 42 U.S.C. 7401 et seq.

_______________________________ _____________________________ Dated: Alexis Strauss, Acting Regional Administrator, EPA Region IX

Part 52, chapter I, title 40 of the Code of Fe deral Regulations is proposed to be amended as follows: PART 52--APPROVAL AND PROMULGATI ON OF IMPLEMENTATION PLANS 1. The authority citation for part 52 continues to read as follows: Authority: 42 U.S.C. 7401 et seq. Subpart D--Arizona 2. Amend § 52.145 by: a. Revising paragraph (i); andThis document is a prepublication version signed by EPA Acting Regional Administrator Alexis Strauss on June 15, 2016. We have taken steps to en sure the accuracy of this version, but it is not the official version.

Page 17 of 22 b. Removing Appendix A to § 52.145--Cement Kiln Control Technology Demonstration Requirements. The revision reads as follows: § 52.145 Visibility protection. * * * * * (k) Source-specific federal implemen tation plan for regional haze at Clarkdale Cement Plant and Rillito Cement Plant -- (1) Applicability. This paragraph (k) applies to each owner/operator of the following cement kilns in the state of Arizona: kiln 4 located at the cement plant in Clarkdale, Arizona, and kiln 4 located at the cement plant in Rillito, Arizona. (2) Definitions. Terms not defined in this paragraph (k )(2) shall have the meaning given them in the Clean Air Act or EPA's regulations implem enting the Clean Air Act. For purposes of this paragraph (k): Ammonia injection shall include any of the following: Anhydrous ammonia, aqueous ammonia or urea injection. Continuous emission monito ring system or CEMS means the equipment required by this section to sample, analyze, measure, and provide, by means of readings recorded at least once every 15 minutes (using an automated data acquisition and handling system (DAHS)), a permanent record of NO X emissions, diluent, or stack gas volumetric flow rate. Kiln operating day means a 24-hour period between 12 midnight and the following midnight during which the kiln operates at any time. Kiln operation means any period when any raw materials are fed into the kiln or any period when any combustion is occurring or fuel is being fired in the kiln. NO X means nitrogen oxides. Owner/operator means any person who owns or who opera tes, controls, or supervises a cement kiln identified in paragra ph (k)(1) of this section. Unit means a cement kiln identified in paragraph (k)(1) of this section. (3) Emissions limitations. (i) The owner/operator of kiln 4 of the Clarkdale Plant, as identified in paragraph (k)(1) of this section, shall not emit or cause to be emitted from kiln 4 NO X in excess of 2.12 pounds of NO X per ton of clinker produce d, based on a rolling 30-kiln operating day basis. (ii) The owner/operator of kiln 4 of the Rillito Pl ant, as identified in paragraph (k)(1) of this section, shall not emit or cause to be emitted from kiln 4 NO X in excess of 3.46 pounds of NO X per ton of clinker produced, based on a rolling 30-kiln operating day basis. (4) Alternative emissions limitation. In lieu of the emission limitation listed in paragraph (k)(3)(i) of this section, the owner/ operator of kiln 4 of the Clar kdale Plant may choose to comply with the following limitation by pr oviding notification per paragra ph (k)(13)(iv) of this section. The owner/operator of kiln 4 of the Clarkdale Plant, as identified in paragraph (k)(1) of this section, shall not emit or cause to be emitted from kiln 4 NO X in excess of 810 tons per year, based on a rolling 12 month basis. (5) Compliance date. (i) The owner/operator of each unit id entified in paragraph (k)(1) of this section shall comply with the NO X emissions limitations and other NO X -related requirements of this paragraph (k)(3) of this se ction no later than December 31, 2018. (ii) If the owner/operator of the Clarkdale Plan t chooses to comply with the emission limit of paragraph (k)(4) of this section in lieu of paragraph (k)(3)(i) of this section, the owner/operator shall comply with the NO X emissions limitations and other NO X -related requirements of paragraph (k)(4) of this section no later than December 31, 2018.This document is a prepublication version signed by EPA Acting Regional Administrator Alexis Strauss on June 15, 2016. We have taken steps to en sure the accuracy of this version, but it is not the official version.

Page 18 of 22 (7) Compliance determination -- (i) Continuous emission mo nitoring system. (A) At all times after the compliance date specified in paragraph (k)(5) of this section, the owner/operator of the unit at the Clarkdale Plant shall maintain, calibra te, and operate a CEMS, in full compliance with the requirements found at 40 CFR 60.63(f) and (g), to accurately measure concentration by volume of NO X , diluent, and stack gas volumetric flow rate from the in-line/raw mill stack, as well as the stack gas volumetric flow rate from the co al mill stack. The CEMS shall be used by the owner/operator to determine compliance with the emission limitation in paragraph (k)(3) of this section, in combination with da ta on actual clinker production. The owner/ope rator must operate the monitoring system and collect data at all requi red intervals at all time s the affected unit is operating, except for periods of monitoring syst em malfunctions, repair s associated with monitoring system malfunctions, and required m onitoring system quality assurance or quality control activities (including, as applicable, calibration checks and required zero and span adjustments). (B) At all times after the comp liance date specified in paragraph (k)(5) of this section, the owner/operator of the unit at the Rillito Plant sh all maintain, calibrate, and operate a CEMS, in full compliance with the requirements found at 40 CFR 60.63(f) and (g), to accurately measure concentration by volume of NO X , diluent, and stack gas volumetric flow rate from the unit. The CEMS shall be used by the owner/operator to determine compliance with the emission limitation in paragraph (k)(3) of this se ction, in combination with data on actual clinker production. The owner/operator must operate the monitoring system a nd collect data at all re quired intervals at all times the affected unit is operating, except for pe riods of monitoring syst em malfunctions, repairs associated with monitoring system malfunctions, and required monitoring system quality assurance or quality cont rol activities (including, as applicable, calibration checks and required zero and span adjustments). (ii) Methods. (A) The owner/operator of each unit sh all record the daily clinker production rates. (B)( 1 ) The owner/operator of each un it shall calculate and record the 30-kiln operating day average emission rate of NO X , in lb/ton of clinker produced, as the total of all hourly emissions data for the cement kiln in the preceding 30-kiln op erating days, divided by th e total tons of clinker produced in that kiln during the same 30-day operating period, using the following equation:

Where: E[D] = 30 kiln operating da y average emission rate of NO X , lb/ton of clinker; C[i] = Concentration of NO X for hour i, ppm; Q[i] = volumetric flow rate of effluent gas for hour i, where C[i] a nd Q[i] are on the same basis (either wet or dr y), scf/hr; Clarkdale? P[i] = total kiln c linker produced during pr oduction hour i, ton/hr; k = conversion factor, 1.194 x 10<-7> for NO X ; and n = number of kiln operating hours over 30 kiln operating days, n = 1 up to 720. ( 2 ) For each kiln operating hour for which the owner/operator does not have at least one valid 15-minute CEMS data value, the owner/operator must use the average emissions rate (lb/hr) from the most recent previous hour for which valid data are available. Hourly clinker production shall be determined by the owner/operator in accordance with the requirements found at 40 CFR 60.63(b).This document is a prepublication version signed by EPA Acting Regional Administrator Alexis Strauss on June 15, 2016. We have taken steps to en sure the accuracy of this version, but it is not the official version.

Page 19 of 22 (C) At the end of each kiln operating day, the ow ner/operator shall calculate and record a new 30-day rolling average emission rate in lb/ton c linker from the arithmetic average of all valid hourly emission rates for the current kiln opera ting day and the previous 29 successive kiln operating days. (D) Upon and after the completion of insta llation of ammonia injection on a unit, the owner/operator shall install, and thereaf ter maintain and operate, inst rumentation to continuously monitor and record levels of am monia injection for that unit. (8) Alternative compliance determination . If the owner/operator of the Clarkdale Plant chooses to comply with the emission limits of paragraph (k )(4) of this section, this paragraph may be used in lieu of paragraph (k)(7) of this section to demonstrate comp liance with the emission limits in paragraph (k)(4) of this section. (i) Continuous emission monitoring system. At all times after the compliance date specified in paragraph (k)(5) of this section, the owner/operator of the unit at the Clarkdale Plant shall maintain, calibrate, and operate a CEMS, in full complianc e with the requirements found at 40 CFR 60.63(f) and (g), to accurately measur e concentration by volume of NO X , diluent, and stack gas volumetric flow rate from the in-line/raw mill stack, as well as the stack gas volumetric flow rate from the coal mill stack. The CEMS shall be used by the owner/operator to determine compliance with the emission limitation in paragraph (k )(3) of this section, in combination with data on actual clinker production. The owner/operator must operate the monitoring system a nd collect data at all required intervals at all times the aff ected unit is operating, except fo r periods of monitoring system malfunctions, repairs associated with monitori ng system malfunctions, and required monitoring system quality assurance or quality control activi ties (including, as applicable, calibration checks and required zero and span adjustments). (ii) Method. Compliance with the ton per year NO X emission limit described in paragraph (k)(4) of this section shall be de termined based on a rolling 12 month basis. The rolling 12-month NO X emission rate for the kiln shall be calculated w ithin 30 days following the end of each calendar month in accordance with the following proced ure: Step one, sum the hourly pounds of NO X emitted for the month just completed and the el even (11) months preceding the month just completed, to calculate the total pounds of NO X emitted over the most recent twelve (12) month period for that kiln; Step tw o, divide the total pounds of NO X calculated from Step one by two thousand (2,000) to calculate the total tons of NO X . Each rolling 12-month NO X emission rate shall include all emissions that occur during all periods within the 12-month period, including emissions from startup, shutdown and malfunction. (iii) Upon and after the completion of instal lation of ammonia injection on the unit, the owner/operator shall install, and thereaf ter maintain and operate, inst rumentation to continuously monitor and record levels of am monia injection for that unit. (9) Recordkeeping. The owner/operator of each unit sha ll maintain the following records for at least five years: (i) All CEMS data, including th e date, place, and time of sampling or measurement; emissions and parameters sampled or measured; and results. (ii) All records of clinker production. (iii) Daily 30-day rolling emission rates of NO X , calculated in accordance with paragraph (k)(7)(ii) of this section. (iv) Records of quality assurance and quality control activities for emissions measuring systems including, but not limited to, any records specified by 40 CFR part 60, Appendix F,This document is a prepublication version signed by EPA Acting Regional Administrator Alexis Strauss on June 15, 2016. We have taken steps to en sure the accuracy of this version, but it is not the official version.

Page 20 of 22 Procedure 1. (v) Records of ammonia consumption, as reco rded by the instrumentation required in paragraph (k)(7)(ii)(D) of this section. (vi) Records of all major maintenance activ ities conducted on emissi on units, air pollution control equipment, CEMS and clin ker production measurement devices. (vii) Any other records specified by 40 CFR pa rt 60, Subpart F, or 40 CFR part 60, Appendix F, Procedure 1. (10) Alternative recordkeeping requirements . If the owner/operator of the Clarkdale Plant chooses to comply with the emission limits of pa ragraph (k)(4) of this s ection, the owner/operator shall maintain the records listed in this paragraph in lieu of the records contained in paragraph (k)(9) of this section. The owner or operator shall maintain the following record s for at least five years: (i) All CEMS data, including th e date, place, and time of sampling or measurement; emissions and parameters sampled or measured; and results. (ii) Monthly rolling 12-m onth emission rates of NO X , calculated in accordance with paragraph (k)(8)(ii) of this section. (iii) Records of quality assurance and quality control activities for emissions measuring systems including, but not limited to, any records specified by 40 CFR part 60, Appendix F, Procedure 1. (iv) Records of ammonia consumption, as re corded by the instrume ntation required in paragraph (k)(8)(iii) of this section. (v) Records of all major main tenance activities conducted on em ission units, air pollution control equipment, and CE MS measurement devices. (vi) Any other records specified by 40 CFR part 60, Subpart F, or 40 CFR part 60, Appendix F, Procedure 1. (11) Reporting. All reports and notifications require d under this paragr aph (k) shall be submitted by the owner/operator to U.S. E nvironmental Protection Agency, Region 9, Enforcement Division via electronic mail to aeo _r9@epa.gov and to Air Division via electronic mail to R9AirPermits@epa.gov. Reports required under this paragraph (k)(11)(iii) through (k)(11)(vii) of this section shall be submitted within 30 days after the applicable compliance date in paragraph (k)(5) of this sec tion and at least semiannually thereaf ter, within 30 days after the end of a semiannual period. The owner/operator may su bmit reports more freque ntly than semiannually for the purposes of synchronizi ng reports required und er this section with other reporting requirements, such as the title V monitoring repo rt required by 40 CFR 70.6( a)(3)(iii)(A), but at no point shall the duration of a semiannual period exceed six months. (i) Prior to commencing construction of the ammonia injection system, the owner/operator shall submit to EPA a report describing the design of the SNCR system. This re port shall include: reagen t type, description of the locations selected for reagent injection, reagent injection rate (expressed as a molar ratio of reagent to exhaust gas), equipment list, eq uipment arrangement, and a summary of kiln characteristics that were relied upon as the design basis for the SNCR system. (ii) Within 30 days following the NO X compliance date in paragra ph (k)(5)(i) of this section, the owner/operator shall submit to EPA a repo rt of any process improvement or debugging activities that were performed on the SNCR system. This report shall include: a description of each process adjustment performed on the SNCR system or the kiln, a discussion of whether the adjustment affected NO X emission rates, a description of the range (if applicable) over which theThis document is a prepublication version signed by EPA Acting Regional Administrator Alexis Strauss on June 15, 2016. We have taken steps to en sure the accuracy of this version, but it is not the official version.

Page 21 of 22 adjustment was examined, and a discussion of how the adjustment will be reflected or account for in kiln operating practices. If CEMS data or ki ln operating data were recorded during process improvement or debugging act ivities, the owner/operator shall submit the recorded CEMS and kiln operating data with the report. The data shall be s ubmitted in an electronic format consistent with and able to be manipulated by a spreadsh eet program such as Microsoft Excel. (iii) The owner/operator shall submit a report th at lists the daily 30-day rolling emission rates for NO X . (iv) The owner/operator shall submit excess emissions reports for NO X limits. Excess emissions means emissions that exceed the emissions limits specified in paragraph (k)(3) of this section. The reports shall include the magnitude, date(s), and duration of each period of excess emissions, specific identification of each period of excess emissions that occurs during startups, shutdowns, and malfunctions of the unit, the natu re and cause of any malfunction (if known), and the corrective action taken or preventative measures adopted. (v) The owner/operator shall s ubmit CEMS performance reports, to include dates and duration of each period during which the CEMS was inoperative (except for zero and span adjustments and calibration checks), reason(s) why the CEMS wa s inoperative and step s taken to prevent recurrence, and any CEMS repairs or adjustments. (vi) The owner/operator shall also submit results of any CEMS performance tests specified by 40 CFR part 60, Appendix F, Procedure 1 (Relativ e Accuracy Test Aud its, Relative Accuracy Audits, and Cylinder Gas Audits). (vii) When no excess emissions have occurred or the CEMS has not been inoperative, repaired, or adjusted during the reporting period, the owner/operator shall st ate such information in the reports required by paragraph (k )(9)(ii) of this section. (12) Alternative reporting requirements. If the owner/operator of the Clarkdale Plant chooses to comply with the emission limits of paragraph (k)(4) of this section, the owner/operator shall submit the reports listed in this paragraph in lieu of the reports contained in paragraph (k)(11) of this section. All reports required under this para graph (k)(12) shall be submitted within 30 days after the applicable compliance da te in paragraph (k)(5) of this section and at least semiannually thereafter, within 30 days after the end of a semiannual period. The owner/operator may submit reports more frequently than semiannually fo r the purposes of synchr onizing reports required under this section with other repo rting requirements, such as the title V monitoring report required by 40 CFR 70.6(a)(3)(iii)(A), but at no point shall the duration of a semia nnual period exceed six months. (i) The owner/operator shall submit a report that lists the monthly rol ling 12-month emission rates for NO X . (ii) The owner/operator shall submit excess emissions reports for NO X limits. Excess emissions means emissions that exceed the emissions limits specified in paragraph (k )(3) of this section. The reports shall include the magnitude, date(s), and duration of each period of excess emissions, specific identification of each pe riod of excess emissions that o ccurs during startups, shutdowns, and malfunctions of the unit, the nature and cause of any malfunction (if known), and the corrective action taken or preventa tive measures adopted. (iii) The owner/operator shall s ubmit CEMS performance reports, to include dates and duration of each period during which the CEMS was inoperative (except for zero and span adjustments and calibration checks), reason(s) why the CEMS wa s inoperative and step s taken to prevent recurrence, and any CEMS repairs or adjustments.This document is a prepublication version signed by EPA Acting Regional Administrator Alexis Strauss on June 15, 2016. We have taken steps to en sure the accuracy of this version, but it is not the official version.

Page 22 of 22 (iv) The owner/operator shall also submit results of any CEMS performance tests specified by 40 CFR part 60, Appendix F, Procedure 1 (Relativ e Accuracy Test Aud its, Relative Accuracy Audits, and Cylinder Gas Audits). (v) When no excess emissions have occurred or the CEMS has not been inoperative, repaired, or adjusted during the reporting period, the owner/operator shall st ate such information in the reports required by paragraph (k )(9)(ii) of this section. (13) Notifications. (i) The owner/operator shall submit notification of commencement of construction of any equipment which is be ing constructed to comply with the NO X emission limits in paragraph (k)(3) of this section. (ii) The owner/operator shall submit semiannual progress reports on construction of any such equipment. (iii) The owner/operator shall submit notificati on of initial startup of any such equipment. (iv) By June 30, 2018, the owner/operator of the Clarkdale Plant shall notify EPA Region 9 by letter whether it will comply with the emission limits in paragraph (k)(3)(i) of this section or whether it will comply with the emission limits in pa ragraph (k)(4) of this s ection. In the event that the owner/operator does not submit timely and proper notificatio n by June 30, 2018, the owner/operator of the Clarkdale Plant may not c hoose to comply with the alternative emission limits in paragraph (k)(4) of this section and shall comply with the emission limits in paragraph (k)(3)(i) of this section. (14) Equipment operation. (i) At all times, including pe riods of startup, shutdown, and malfunction, the owner or operator shall, to the ex tent practicable, maintain and operate the unit including associated air pollution control equipment in a manner cons istent with good air pollution control practices for minimizing emissions. Pollu tion control equipment shall be designed and capable of operating properly to minimize emissi ons during all expected operating conditions. Determination of whether acceptable operating and maintenance procedures are being used will be based on information available to the Regiona l Administrator which may include, but is not limited to, monitoring results, review of operating and maintenance procedures, and inspection of the unit. (ii) After completion of installation of ammonia injection on a unit, the owner or operator shall inject sufficient ammonia to achieve compliance with NO X emission limits set forth in paragraph (k)(3) of this section for that unit whil e preventing excessive ammonia emissions. (15) Enforcement. Notwithstanding any other provision in this implementation plan, any credible evidence or information relevant as to whether the unit would have been in compliance with applicable requirements if the appropria te performance or compliance test had been performed, can be used to estab lish whether or not the owner or operator has violated or is in violation of any standard or appl icable emission limit in the plan.