The EPA Acting Regional Administrator, Alexis Strauss, signed the following rule on June 15, 

2016 and EPA is submitting it for publication in the 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 publication 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 PROTECTION AGENCY 

40 CFR Part 52 

[EPA-R09-OAR-2015-0846, FRL-YYY] 

Promulgation of Air Quality Implementation 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 revise provisions of 

the Arizona Regional Haze Federal Implementation Plan (FIP) applicable to the Phoenix Cement 

Company (PCC) Clarkdale Plant and the CalPortland Cement (CPC) Rillito Plant. In response to 

requests for reconsideration from the plants’ owners, we propose to replace the control technology 

optimization requirements for nitrogen oxides (NOX) 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 hearing 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 removed 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 ensure the accuracy of this version, but it is not 

the official version. 

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the EPA may publish any comment received to its public docket. Do not submit electronically any 

information you consider to be Confidential Business Information (CBI) or other information 

whose disclosure is restricted by statute. Multimedia submissions (audio, video, etc.) must be 

accompanied by a written comment. The written comment is considered the official comment and 

should include discussion of all points you wish to make. The EPA will generally not consider 

comments or comment contents located outside of the primary submission (i.e. on the web, cloud, 

or other file sharing system). For additional submission methods, please contact the person 

identified in the “FOR FURTHER INFORMATION CONTACT” section. For the full EPA public 

comment policy, information about CBI or multimedia submissions, and general guidance on 

making effective comments, please visit http://www2.epa.gov/dockets/commenting-epa-dockets. 

FOR FURTHER INFORMATION CONTACT: Vijay Limaye, U.S. EPA, Region 9, Planning 

Office, Air Division, Air-2, 75 Hawthorne 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 Clarkdale Plant and the CPC Rillito Plant 

IV. The EPA’s Proposed Action 

V. Statutory and Executive Order Reviews 

I. General Information 

A. Definitions 
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For the purpose of this document, we are giving 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 Department 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 NOX 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 selective non-catalytic reduction. 

 The initials SRPMIC mean or refer to Salt River Pima-Maricopa Indian Community. 

B. Docket 

The proposed action relies on documents, information, and data that are listed in the index 

 

1

 Although states and tribes may designate as Class I additional areas which they consider to have visibility as an 

important value, the requirements of the visibility program set forth in section 169A of the CAA apply only to 

“mandatory Class I Federal areas.” 
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on http://www.regulations.gov under docket number EPA-R09-OAR-2015-0846. Although listed 

in the index, some information is not publicly available (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 Division, AIR-2, EPA Region 9, 75 Hawthorne Street, San Francisco, 

CA 94105. The EPA requests that you contact the 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 State Implementation Plan (SIP) for additional 

background regarding the visibility protection provisions of the CAA and the Regional Haze Rule.2

 

Congress created a program for protecting visibility in the nation's national parks and 

wilderness areas in section 169A of the 1977 Amendments to the CAA. This section of the CAA 

 

2

 77 FR 42834, 42837-42839 (July 20, 2012), (Arizona Regional Haze “Phase 1” Rule) 77 FR 75704, 75709-75712 

(December 21, 2012), (Arizona Regional Haze “Phase 2” Rule). 
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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 the CAA requires states to revise their 

SIPs to contain such measures as may be necessary to make reasonable progress towards the 

natural visibility goal. In the 1990 CAA Amendments, Congress 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 activities located across a broad geographic area.4

 We 

promulgated the Regional Haze Rule in 1999, which requires states to develop and implement 

SIPs to ensure reasonable progress toward improving visibility in mandatory Class I Federal areas5

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 promulgated two final rules approving in part and 

disapproving in part the Arizona Regional Haze SIP. The first final rule addressed the State’s 

BART determinations for three power plants (Apache 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 disapproval of the State’s analysis of reasonable 

progress measures for point sources of NOX.

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 all international parks that were 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 (December 5, 2012). 8

 78 FR 46142 (July 30, 2013). 
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In a third final rule, the EPA promulgated a FIP addressing the requirements of the 

Regional Haze Rule and interstate visibility transport 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 NOX emission controls applicable to PCC Clarkdale Plant Kiln 4 and CPC Rillito 

Plant Kiln 4 under the reasonable progress requirements of the Regional Haze Rule. In particular, 

the EPA established two alternative emission limits for NOX on Kiln 4 of the Clarkdale Plant: a 

2.12 lb/ton limit or an 810 tons/year limit. The lb/ton limit equates to the installation of SNCR, 

based on a 50 percent control efficiency, while the ton/year limit could be met either by installing 

SNCR or by maintaining recent production levels. We set an emission limit for NOX 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 compliance deadline for the final NOX emission 

limits of December 31, 2018. Finally, in response to comments alleging that SNCR control 

efficiencies of 50 percent for Kiln 4 at the Clarkdale 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 control 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). 
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objections to the optimization requirements in the FIP. CPC asserted that the requirements were 

burdensome, expensive, and unnecessary, given that CPC had already “evaluated fuels, fuel 

fineness, and the other characteristics 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 cement manufacturing operations” at the Clarkdale 

Plant.12 PCC further asserted that requirements would 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, granting 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 Clarkdale Plant and the CPC Rillito Plant 

A. The EPA’s Evaluation of Control Technology Demonstration Requirements 

In light of the objections to the control technology 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 requirements are to ensure that the NOX emission limits for the cement 

kilns are appropriate and to ensure that performance 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; Arizona; 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). 
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optimized.15 In developing this proposed action on reconsideration, we have considered whether 

it is possible to achieve these objectives through other means. In particular, we have identified 

additional information regarding SNCR performance and NOX 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 consider it necessary for PCC and CPC to adhere to the 

relatively detailed and prescriptive control technology demonstration requirements in the existing 

FIP. We are therefore proposing to remove the control 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 control technology demonstration requirements for 

Kiln 4 (the preheater/precalciner kiln) at the CPC Rillito Plant based on NOX 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 required the installation of SNCR on the single 

preheater/precalciner kiln at the Mojave Plant. As part of the consent decree, this 

preheater/precalciner kiln at the Mojave Plant was subject to certain control technology 

demonstration requirements. Commonly referred to as a “test and set” approach, these consent 

decree provisions required CPC to design and install an SNCR system, develop a protocol for 

optimizing its operation, record NOX emission data over a long-term period, and propose a sitespecific emission limit based on those results. 

 

15 See 79 FR 52455-52456, 52462. 
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As noted in the response to comments in our September 3, 2014 final rule, 16 CPC 

submitted comments noting certain site-specific aspects 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 NOX 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 the SNCR system at the Mojave Plant could be 

expected to achieve in the range of 30-60% control efficiency. Given that this range included 

control efficiencies that were significantly higher 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 rule would be appropriate in order to allow us 

to evaluate whether or not Rillito Kiln 4 could be further optimized to achieve a more stringent 

control efficiency. 

Following promulgation of the final rule on September 3, 2014, the Mojave Plant 

completed a 270-day demonstration period of its SNCR system.18 Based upon the consent decree 

methodology, the emission data from the demonstration period indicate a NOX limit for the Mojave 

Plant kiln of 2.70 lb/ton on a rolling 30-kiln-operating-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 CalPortland Company’s Rillito Cement Plant.” To summarize, CPC 

asserted that an SNCR system on Rillito Kiln 4 would operate with less efficient exhaust mixing, lower ammonia 

injection temperatures, and lower oxygen concentrations, 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 NOX emission rate of 4.5 lb/ton. This value was based on the highest of recent 
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 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 NOX 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 the relatively detailed and prescriptive control 

technology demonstration requirements in the existing FIP. We are therefore proposing to remove 

the control technology demonstration requirements from the FIP. As explained in section III.B 

below, we are proposing to replace the control technology demonstration requirements with a set 

of revised recordkeeping and reporting requirements that will require CPC to report similar 

information regarding SNCR system design and optimization, but in a less prescribed manner. 

2. Clarkdale Plant Kiln 4 

The EPA is also proposing to remove the control technology demonstration requirements 

for Kiln 4 (the preheater/precalciner kiln) at the PCC Clarkdale Plant based on the NOX emission 

data from the preheater/precalciner kiln at the CPC Mojave Plant. In the case of Clarkdale Kiln 4, 

the relatively recent construction of the kiln21 and its generally lower pre-control NOX emission 

rates22 indicate that an SNCR system on Clarkdale Kiln 4 would be able to achieve a lower NOX

emission limit than the Mojave Plant. The final NOX limit promulgated for Clarkdale Kiln 4 is 

2.12 lb/ton, on a rolling 30-kiln-operating-day basis, which is based on a 50% control efficiency. 

As noted in the previous section, the emission data from the Mojave Plant demonstration period 

 

source test results, as summarized in spreadsheet “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 control 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 NOX 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 determination, Clarkdale Kiln 4 has a baseline NOX emission rate of 3.25 

lb/ton. The Mojave baseline emission rate was 4.50 lb/ton. 
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indicated a final NOX 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 the Mojave Plant, we 

consider the final limit for Clarkdale Kiln 4 to be sufficiently stringent 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 demonstration 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 proposing 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 system design and optimization, 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 detailed optimization requirements 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 recordkeeping requirements that involve 

documentation and submittal of certain design and 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 construction of the ammonia injection system at 

Clarkdale Kiln 4 and Rillito Kiln 4 respectively, including information regarding reagent type, 

locations selected for reagent injection, reagent injection rate, equipment arrangement, and kiln 

characteristics. In addition, PCC and CPC would be required to submit a report of SNCR 
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debugging and process improvement activities, including a description of each process 

adjustment performed on the SNCR system, a discussion of whether the adjustment affected the 

NOX emission rate, a description of the range over which the adjustment was examined, and a 

discussion of how the adjustment will be reflected or accounted for in kiln operating practices. 

PCC and CPC would also be required to submit any CEMS data and kiln operating data collected 

during the debugging and process improvement activities. 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 implementation plan shall not be approved by 

the Administrator if the revision would interfere with any applicable requirement concerning 

attainment and reasonable further progress or any other applicable requirement of the CAA.23

Today’s proposed revisions to the Arizona Regional 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 demonstration requirements with a series of recordkeeping and 

reporting requirements would not alter any of the 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 proposes to revise the Arizona Regional Haze 

FIP to replace the control technology optimization requirements at the PCC Clarkdale Plant and 

the CPC Rillito Plant with a series of recordkeeping and reporting requirements. Please note that 

 

23 CAA Section 110(l), 42 U.S.C. 7410(l). 
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while the proposed regulatory text includes the entirety of 40 CFR 52.145(k), we are only 

proposing to revise those elements of the regulation related to optimization requirements. 

V. Statutory and Executive Order Reviews 

Additional information about these statutes and Executive Orders can be found at 

http://www2.epa.gov/laws-regulations/laws-and-executive-orders. 

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

Improving Regulation and Regulatory Review 

This 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, January 21, 2011). This proposed rule applies 

to only one facility and is therefore not a rule of general applicability. 

B. Paperwork Reduction Act (PRA) 

This action does not impose an information collection burden under the 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 significant 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 proposed 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 jurisdiction that is a government 

of a city, county, town, school district or special district with a population of less than 50,000; 

and (3) a small organization that is any not-for-profit enterprise which is independently owned 

and operated and is not dominant in its field. Pursuant to 13 CFR 121.201, footnote 1, a firm is 
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small if it is in NAICS 327310 (cement manufacturing) 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 mandate 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 implications. It will not have substantial direct 

effects on the states, on the relationship between the national government and the states, or in the 

distribution of power and responsibilities among the various levels of government, as specified in 

Executive Order 13132. 

F. Executive Order 13175: Consultation and Coordination with Indian Tribal Governments 

This action has tribal implications. However, 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. 
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apply to the PCC Clarkdale Plant. The profits from the Clarkdale Plant are used to provide 

government services to SRPMIC's members. 

The EPA consulted with tribal officials under the EPA Policy on Consultation and 

Coordination with Indian Tribes early in the process of developing this regulation to permit them 

to have meaningful and timely input into its development.27 

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

Safety Risks 

The EPA interprets Executive Order 13045 as applying only to those regulatory actions 

that concern environmental health or safety risks that the EPA has reason to believe may 

disproportionately affect children, per the definition of “covered regulatory action” in section 2-

202 of the Executive Order. This action is not subject to Executive Order 13045 because it does 

not concern an environmental health risk or safety risk. 

H. Executive Order 13211: Actions Concerning Regulations 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 involve 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. 
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does not change the level of environmental 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 section 307(d). Section 307(d) establishes procedural requirements 

specific to certain rulemaking actions under the CAA. Pursuant to CAA section 307(d)(1)(B), the 

revision of the provisions of the Arizona Regional 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 pollution 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 Federal Regulations is proposed to be amended as 

follows: 

 

PART 52--APPROVAL AND PROMULGATION 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); and 
This document is a prepublication version signed by EPA Acting Regional Administrator Alexis 

Strauss on June 15, 2016. We have taken steps to ensure the accuracy of this version, but it is not 

the official version. 

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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 implementation 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 implementing 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 monitoring 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 NOX 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. 

NOX means nitrogen oxides. 

Owner/operator means any person who owns or who operates, controls, or supervises a cement 

kiln identified in paragraph (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 NOX in excess 

of 2.12 pounds of NOX per ton of clinker produced, based on a rolling 30-kiln operating day basis. 

(ii) The owner/operator of kiln 4 of the Rillito Plant, as identified in paragraph (k)(1) of this 

section, shall not emit or cause to be emitted from kiln 4 NOX in excess of 3.46 pounds of NOX

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 Clarkdale Plant may choose to comply 

with the following limitation by providing notification per paragraph (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 NOX in excess of 810 tons per year, based on a 

rolling 12 month basis. 

(5) Compliance date. (i) The owner/operator of each unit identified in paragraph (k)(1) of this 

section shall comply with the NOX emissions limitations and other NOX -related requirements of 

this paragraph (k)(3) of this section no later than December 31, 2018. 

(ii) If the owner/operator of the Clarkdale Plant 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 NOX emissions limitations and other NOX-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 ensure the accuracy of this version, but it is not 

the official version. 

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 (7) Compliance determination -- (i) Continuous emission monitoring 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, 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 NOX, 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 and collect data at all required intervals at all times the affected unit is 

operating, except for periods of monitoring system malfunctions, repairs associated with 

monitoring system malfunctions, and required monitoring system quality assurance or quality 

control activities (including, as applicable, calibration checks and required zero and span 

adjustments). 

(B) At all times after the compliance date specified in paragraph (k)(5) of this section, the 

owner/operator of the unit at the Rillito Plant shall 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 NOX, 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 section, in combination with data on actual clinker production. The 

owner/operator must operate the monitoring system and collect data at all required intervals at all 

times the affected unit is operating, except for periods of monitoring system malfunctions, repairs 

associated with monitoring system malfunctions, and required monitoring system quality 

assurance or quality control activities (including, as applicable, calibration checks and required 

zero and span adjustments). 

(ii) Methods. (A) The owner/operator of each unit shall record the daily clinker production 

rates. 

(B)(1) The owner/operator of each unit shall calculate and record the 30-kiln operating day 

average emission rate of NOX, in lb/ton of clinker produced, as the total of all hourly emissions 

data for the cement kiln in the preceding 30-kiln operating days, divided by the 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 day average emission rate of NOX, lb/ton of clinker; 

 C[i] = Concentration of NOX for hour i, ppm; 

 Q[i] = volumetric flow rate of effluent gas for hour i, where C[i] and Q[i] are on the same 

basis (either wet or dry), scf/hr; Clarkdale? 

 P[i] = total kiln clinker produced during production hour i, ton/hr; 

 k = conversion factor, 1.194 x 10<-7> for NOX; 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 ensure the accuracy of this version, but it is not 

the official version. 

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(C) At the end of each kiln operating day, the owner/operator shall calculate and record a new 

30-day rolling average emission rate in lb/ton clinker from the arithmetic average of all valid 

hourly emission rates for the current kiln operating day and the previous 29 successive kiln 

operating days. 

(D) Upon and after the completion of installation of ammonia injection on a unit, the 

owner/operator shall install, and thereafter maintain and operate, instrumentation to continuously 

monitor and record levels of ammonia 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 compliance 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 compliance with the requirements found at 40 CFR 60.63(f) 

and (g), to accurately measure concentration by volume of NOX, 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 and collect data at all required 

intervals at all times the affected unit is operating, except for periods of monitoring system 

malfunctions, repairs associated with monitoring system malfunctions, and required monitoring 

system quality assurance or quality control activities (including, as applicable, calibration checks 

and required zero and span adjustments). 

(ii) Method. Compliance with the ton per year NOX emission limit described in paragraph 

(k)(4) of this section shall be determined based on a rolling 12 month basis. The rolling 12-month 

NOX emission rate for the kiln shall be calculated within 30 days following the end of each calendar 

month in accordance with the following procedure: Step one, sum the hourly pounds of NOX

emitted for the month just completed and the eleven (11) months preceding the month just 

completed, to calculate the total pounds of NOX emitted over the most recent twelve (12) month 

period for that kiln; Step two, divide the total pounds of NOX calculated from Step one by two 

thousand (2,000) to calculate the total tons of NOX. Each rolling 12-month NOX 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 installation of ammonia injection on the unit, the 

owner/operator shall install, and thereafter maintain and operate, instrumentation to continuously 

monitor and record levels of ammonia injection for that unit. 

(9) Recordkeeping. The owner/operator of each unit shall maintain the following records for 

at least five years: 

(i) All CEMS data, including the 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 NOX, 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, 
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Strauss on June 15, 2016. We have taken steps to ensure the accuracy of this version, but it is not 

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Procedure 1. 

(v) Records of ammonia consumption, as recorded by the instrumentation required in 

paragraph (k)(7)(ii)(D) of this section. 

(vi) Records of all major maintenance activities conducted on emission units, air pollution 

control equipment, CEMS and clinker production measurement devices. 

(vii) Any other records specified by 40 CFR part 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 paragraph (k)(4) of this section, 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 records for at least five 

years: 

(i) All CEMS data, including the date, place, and time of sampling or measurement; emissions 

and parameters sampled or measured; and results. 

(ii) Monthly rolling 12-month emission rates of NOX, 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 recorded by the instrumentation required in 

paragraph (k)(8)(iii) of this section. 

(v) Records of all major maintenance activities conducted on emission units, air pollution 

control equipment, and CEMS 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 required under this paragraph (k) shall be 

submitted by the owner/operator to U.S. Environmental 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 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 

for the purposes of synchronizing reports required under this section with other reporting 

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 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 report shall include: reagent type, description of 

the locations selected for reagent injection, reagent injection rate (expressed as a molar ratio of 

reagent to exhaust gas), equipment list, equipment 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 NOX compliance date in paragraph (k)(5)(i) of this section, 

the owner/operator shall submit to EPA a report 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 NOX emission rates, a description of the range (if applicable) over which the 
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Strauss on June 15, 2016. We have taken steps to ensure the accuracy of this version, but it is not 

the official version. 

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adjustment was examined, and a discussion of how the adjustment will be reflected or account for 

in kiln operating practices. If CEMS data or kiln operating data were recorded during process 

improvement or debugging activities, the owner/operator shall submit the recorded CEMS and kiln 

operating data with the report. The data shall be submitted in an electronic format consistent with 

and able to be manipulated by a spreadsheet program such as Microsoft Excel. 

(iii) The owner/operator shall submit a report that lists the daily 30-day rolling emission rates 

for NOX. 

(iv) The owner/operator shall submit excess emissions reports for NOX 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 nature and cause of any malfunction (if known), and 

the corrective action taken or preventative measures adopted. 

(v) The owner/operator shall submit 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 was inoperative and steps 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 (Relative Accuracy Test Audits, 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 state 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 paragraph (k)(12) shall be submitted within 30 days 

after the applicable compliance date 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 for the purposes of synchronizing reports required 

under this section with other reporting 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 semiannual period exceed six 

months. 

(i) The owner/operator shall submit a report that lists the monthly rolling 12-month emission 

rates for NOX. 

(ii) The owner/operator shall submit excess emissions reports for NOX 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 nature and cause of any malfunction (if known), and the corrective 

action taken or preventative measures adopted. 

(iii) The owner/operator shall submit 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 was inoperative and steps taken to prevent 

recurrence, and any CEMS repairs or adjustments. 
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the official version. 

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(iv) The owner/operator shall also submit results of any CEMS performance tests specified by 

40 CFR part 60, Appendix F, Procedure 1 (Relative Accuracy Test Audits, 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 state 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 being constructed to comply with the NOX 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 notification 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 paragraph (k)(4) of this section. In the event that 

the owner/operator does not submit timely and proper notification by June 30, 2018, the 

owner/operator of the Clarkdale Plant may not choose 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 periods of startup, shutdown, and 

malfunction, the owner or operator shall, to the extent practicable, maintain and operate the unit 

including associated air pollution control equipment in a manner consistent with good air pollution 

control practices for minimizing emissions. Pollution control equipment shall be designed and 

capable of operating properly to minimize emissions during all expected operating conditions. 

Determination of whether acceptable operating and maintenance procedures are being used will 

be based on information available to the Regional 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 NOX emission limits set forth in paragraph 

(k)(3) of this section for that unit while 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 appropriate performance or compliance test had been 

performed, can be used to establish whether or not the owner or operator has violated or is in 

violation of any standard or applicable emission limit in the plan.