Document ID: EPA-R08-OAR-2017-0062-0051
Agency: epa
Document Type: Rule
Title: Air Quality State Implementation Plans; Approvals and Promulgations: Montana; Regional Haze Federal Implementation Plan
Posted Date: 2017-09-12T04:00Z

[Federal Register Volume 82, Number 175 (Tuesday, September 12, 2017)]
[Rules and Regulations]
[Pages 42738-42746]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2017-19210]

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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 52

[EPA-R08-OAR-2017-0062; FRL-9967-62-Region 8]

Approval and Promulgation of Air Quality Implementation Plans; 
Montana; Regional Haze Federal Implementation Plan

AGENCY: Environmental Protection Agency (EPA).

ACTION: Final rule.

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SUMMARY: The Environmental Protection Agency (EPA) is finalizing 
revisions pursuant to section 110 of the Clean Air Act (CAA) to the 
Federal Implementation Plan (FIP) addressing regional haze in the State 
of Montana. The EPA promulgated a FIP on September 18, 2012, in 
response to the State's decision in 2006 to not submit a regional haze 
State Implementation Plan (SIP). We proposed revisions to that FIP on 
April 14, 2017, and are now finalizing those revisions. Specifically, 
the EPA is finalizing revisions to the FIP's requirement for best 
available retrofit technology (BART) for the Trident cement kiln owned 
and operated by Oldcastle Materials Cement Holdings, Inc. (Oldcastle), 
located in Three Forks, Montana. In response to a request from 
Oldcastle, and in light of new information that was not available at 
the time we originally promulgated the FIP, we are revising the 
nitrogen oxides (NOX) emission limit for the Trident cement 
kiln. We are also correcting errors we made in our FIP regarding the 
reasonable progress determination for the Blaine County #1 Compressor 
Station and the instructions for compliance determinations for 
particulate matter (PM) BART emission limits at electrical generating 
units (EGUs) and cement kilns. This action does not address the U.S. 
Court of Appeals for the Ninth Circuit's June 9, 2015 vacatur and 
remand of portions of the FIP regarding the Colstrip and Corette power 
plants; we plan to address the court's remand in a separate action.

DATES: This rule is effective October 12, 2017.

ADDRESSES: The EPA has established a docket for this action under 
Docket ID No. EPA-R08-OAR-2017-0062. All documents in the docket are 
listed on the http://www.regulations.gov Web site. Although listed in 
the index, some information is not publicly available, e.g., CBI or 
other information whose disclosure is restricted by statute. Certain 
other material, such as

[[Page 42739]]

copyrighted material, is not placed on the Internet and will be 
publicly available only in hard copy form. Publicly available docket 
materials are available through http://www.regulations.gov, or please 
contact the person identified in the FOR FURTHER INFORMATION CONTACT 
section for additional availability information.

FOR FURTHER INFORMATION CONTACT: Jaslyn Dobrahner, Air Program, EPA, 
Region 8, Mailcode 8P-AR, 1595 Wynkoop Street, Denver, Colorado 80202-
1129, (303) 312-6252, dobrahner.jaslyn@epa.gov.

SUPPLEMENTARY INFORMATION: Throughout this document whenever ``we,'' 
``us,'' or ``our'' is used, we mean the EPA.

Table of Contents

I. Proposed Action
II. Background
    A. Requirements of the Clean Air Act and the EPA's Regional Haze 
Rule
    B. Best Available Retrofit Technology (BART)
    C. Reasonable Progress Requirements
    D. Consultation With Federal Land Managers (FLMs)
    E. Regulatory and Legal History of the 2012 Montana FIP
III. Public Comments and EPA Responses
IV. Final Action
V. Statutory and Executive Order Reviews

I. Proposed Action

    On September 18, 2012, the EPA promulgated a FIP that included a 
NOX BART emission limit for the Holcim (US), Inc., Trident 
cement kiln located in Three Forks, Montana.1 2 On April 14, 
2017, the EPA proposed to revise the 2012 FIP with respect to the BART 
emission limit for the Trident cement kiln.\3\ Specifically, in 
response to newly available information regarding the efficiency of 
controls we determined in our 2012 FIP to be BART, the EPA proposed to 
revise the NOX emission limit from 6.5 lb/ton clinker to 7.6 
lb/ton clinker (both as 30-day rolling averages). The EPA also proposed 
to correct errors we made in our FIP regarding the reasonable progress 
determination for the Blaine County #1 Compressor Station and in the 
instructions for compliance determinations for PM BART emission limits 
at EGUs and cement kilns. The proposed correction to our erroneous 
reasonable progress determination for the Blaine County #1 Compressor 
Station would result in the source no longer being subject to 
reasonable progress requirements and would thus remove the 
NOX emission limit of 21.8 lbs NOX/hr (average of 
three stack test runs). The proposed correction to the PM compliance 
determination instructions would include regulatory text that was 
inadvertently left out of the September 18, 2012 final rule and would 
allow sources to retain the PM stack testing schedule already 
established under state permits. The EPA proposed to revise the 
specific portions of Montana's regional haze FIP under our general 
rulemaking and CAA-specific authorities, as appropriate. See 5 U.S.C. 
551(5); 42 U.S.C. 7601(a)(1), 7410(c)(1), 7410(k)(6). We did not 
address the Ninth Circuit's June 9, 2015 vacatur and remand of 
unrelated portions of the FIP in this action and plan to address the 
court's remand in a separate action.
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    \1\ Oldcastle Materials Cement Holdings, Inc., (Oldcastle) is 
the current owner and operator of the Trident cement kiln.
    \2\ 77 FR 57864.
    \3\ 82 FR 17948.
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II. Background

A. Requirements of the Clean Air Act and the EPA's Regional Haze Rule

    In section 169A of the 1977 Amendments to the CAA, Congress created 
a program for protecting visibility in the nation's national parks and 
wilderness areas. This section of the CAA 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.'' \4\ On December 2, 
1980, the EPA promulgated regulations to address visibility impairment 
in Class I areas that is ``reasonably attributable'' to a single source 
or small group of sources, i.e., reasonably attributable visibility 
impairment.\5\ These regulations represented the first phase in 
addressing visibility impairment. The EPA deferred action on regional 
haze that emanates from a variety of sources until monitoring, modeling 
and scientific knowledge about the relationships between pollutants and 
visibility impairment were improved.
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    \4\ 42 U.S.C. 7491(a). 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). In accordance with section 169A of the CAA, 
EPA, in consultation with the Department of Interior, promulgated a 
list of 156 areas where visibility is identified as an important 
value. 44 FR 69122 (November 30, 1979). The extent of a mandatory 
Class I area includes subsequent changes in boundaries, such as park 
expansions. 42 U.S.C. 7472(a). 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.'' Each mandatory Class I Federal 
area is the responsibility of a ``Federal Land Manager.'' 42 U.S.C. 
7602(i). When we use the term ``Class I area'' in this section, we 
mean a ``mandatory Class I Federal area.''
    \5\ 45 FR 80084, 80084 (December 2, 1980).
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    Congress added section 169B to the CAA in 1990 to address regional 
haze issues. The EPA promulgated a rule to address regional haze on 
July 1, 1999.\6\ The Regional Haze Rule (RHR) revised the existing 
visibility regulations to integrate provisions addressing regional haze 
and established a comprehensive visibility protection program for Class 
I areas. The requirements for regional haze, found at 40 CFR 51.308 and 
51.309, are included in the EPA's visibility protection regulations at 
40 CFR 51.300-51.309. The EPA revised the RHR on January 10, 2017.\7\
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    \6\ 64 FR 35714, 35714 (July 1, 1999) (codified at 40 CFR part 
51, subpart P).
    \7\ 82 FR 3078 (January 10, 2017).
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    The CAA requires each state to develop a SIP to meet various air 
quality requirements, including protection of visibility.\8\ Regional 
haze SIPs must assure reasonable progress toward the national goal of 
achieving natural visibility conditions in Class I areas. A state must 
submit its SIP and SIP revisions to the EPA for approval. Once 
approved, a SIP is enforceable by the EPA and citizens under the CAA; 
that is, the SIP is federally enforceable. If a state elects not to 
make a required SIP submittal, fails to make a required SIP submittal 
or if we find that a state's required submittal is incomplete or not 
approvable, then we must promulgate a FIP to fill this regulatory 
gap.\9\ Montana is on the path towards a regional haze SIP and is 
working closely with the Region to replace all or portions of the FIP 
as soon as practicable.
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    \8\ 42 U.S.C. 7410(a), 7491, and 7492(a), CAA sections 110(a), 
169A, and 169B.
    \9\ 42 U.S.C. 7410(c)(1).
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B. Best Available Retrofit Technology (BART)

    Section 169A of the CAA directs states, or the EPA if developing a 
FIP, to evaluate the use of retrofit controls at certain larger, often 
uncontrolled, older stationary sources in order to address visibility 
impacts from these sources. Specifically, section 169A(b)(2)(A) of the 
CAA requires states' implementation plans to contain such measures as 
may be necessary to make reasonable progress toward the natural 
visibility goal, including a requirement that certain categories of 
existing major stationary sources built between 1962 and 1977 procure, 
install, and operate the ``Best Available Retrofit Technology'' as 
determined by the states, or in the case of a FIP, the EPA. Under the 
RHR, states or the EPA are

[[Page 42740]]

directed to conduct BART determinations for such ``BART-eligible'' 
sources that may reasonably be anticipated to cause or contribute to 
any visibility impairment in a Class I area.
    On July 6, 2005, the EPA published the Guidelines for BART 
Determinations under the RHR at appendix Y to 40 CFR part 51 
(hereinafter referred to as the ``BART Guidelines'') to assist states 
and the EPA in determining which sources should be subject to the BART 
requirements and the appropriate emission limits for each applicable 
source.\10\ The process of establishing BART emission limitations 
follows three steps: First, identify the sources that meet the 
definition of ``BART-eligible source'' set forth in 40 CFR 51.301; \11\ 
second, determine which of these sources ``emits any air pollutant 
which may reasonably be anticipated to cause or contribute to any 
impairment of visibility in any such area'' (a source which fits this 
description is ``subject to BART''); and third, for each source subject 
to BART, identify the best available type and level of control for 
reducing emissions. Section 169A(g)(7) of the CAA requires that states, 
or the EPA if developing a FIP, must consider the following five 
factors in making BART determinations: (1) The costs of compliance; (2) 
the energy and non-air quality environmental impacts of compliance; (3) 
any existing pollution control technology in use at the source; (4) the 
remaining useful life of the source; and (5) the degree of improvement 
in visibility which may reasonably be anticipated to result from the 
use of such technology. States or the EPA must address all visibility-
impairing pollutants emitted by a source in the BART determination 
process. The most significant visibility impairing pollutants are 
sulfur dioxide (SO2), NOX, and PM.
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    \10\ 70 FR 39104.
    \11\ BART-eligible sources are those sources that have the 
potential to emit 250 tons or more of a visibility-impairing air 
pollutant, were not in operation prior to August 7, 1962, but were 
in existence on August 7, 1977, and whose operations fall within one 
or more of 26 specifically listed source categories. 40 CFR 51.301.
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    A SIP or FIP addressing regional haze must include source-specific 
BART emission limits and compliance schedules for each source subject 
to BART. Once a state or the EPA has made a BART determination, the 
BART controls must be installed and operated as expeditiously as 
practicable, but no later than five years after the date of the EPA's 
approval of the final SIP or the date of the EPA's promulgation of the 
FIP.\12\ In addition to what is required by the RHR, general SIP 
requirements mandate that the SIP or FIP include all regulatory 
requirements related to monitoring, recordkeeping, and reporting for 
the BART emission limitations. See CAA section 110(a); 40 CFR part 51, 
subpart K.
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    \12\ CAA section 169A(g)(4); 40 CFR 51.308(e)(1)(iv).
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C. Reasonable Progress Requirements

    In addition to BART requirements, as mentioned previously each 
regional haze SIP or FIP must contain measures as necessary to make 
reasonable progress towards the national visibility goals. As part of 
determining what measures are necessary to make reasonable progress, 
the SIP or FIP must first identify anthropogenic sources of visibility 
impairment that are to be considered in developing the long-term 
strategy for addressing visibility impairment.\13\ States or the EPA 
must then consider the four statutory reasonable progress factors in 
selecting control measures for inclusion in the long-term strategy--the 
costs of compliance, the time necessary for compliance, the energy and 
non-air quality environmental impacts of compliance, and the remaining 
useful life of potentially affected sources. See CAA section 169A(g)(1) 
(defining the reasonable progress factors); 40 CFR 51.308(d)(1)(i)(A). 
Finally, the SIP or FIP must establish reasonable progress goals (RPGs) 
for each Class I area within the state for the plan implementation 
period (or ``planning period''), based on the measures included in the 
long-term strategy.\14\ If a RPG provides for a slower rate of 
improvement in visibility than the rate needed to attain the national 
goal by 2064, the SIP or FIP must demonstrate, based on the four 
reasonable progress factors, why the rate to attain the national goal 
by 2064 is not reasonable and the RPG is reasonable.\15\
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    \13\ 40 CFR 51.308(d)(3)(iv).
    \14\ 40 CFR 51.308(d), (f).
    \15\ 40 CFR 51.308(d)(1)(ii).
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D. Consultation With Federal Land Managers (FLMs)

    The RHR requires that a state, or the EPA if promulgating a FIP 
that fills a gap in the SIP with respect to this requirement, consult 
with FLMs before adopting and submitting a required SIP or SIP 
revision, or a required FIP or FIP revision.\16\ Further, the EPA must 
include in its proposed FIP a description of how it addressed any 
comments provided by the FLMs. Finally, a FIP must provide procedures 
for continuing consultation between the EPA and FLMs regarding the 
EPA's FIP, visibility protection program, including development and 
review of FIP revisions, five-year progress reports, and the 
implementation of other programs having the potential to contribute to 
impairment of visibility in Class I areas.
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    \16\ 40 CFR 51.308(i).
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E. Regulatory and Legal History of the 2012 Montana FIP

    On September 18, 2012, the EPA promulgated a FIP to address 
Montana's regional haze obligations that included BART emission limits 
for two power plants and two cement kilns, and an emission limit for a 
natural gas compressor station based on reasonable progress 
requirements.\17\ The EPA took this action because Montana decided not 
to submit a regional haze SIP, knowing that as a result the EPA would 
be required to promulgate a FIP.\18\ The BART emission limits for the 
two cement kilns and the reasonable progress requirements for the 
compressor station addressed in this action were not at issue in the 
petitions filed with the Ninth Circuit Court of Appeals.\19\ The EPA 
plans to address the court's remand in a separate action.
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    \17\ 77 FR 57864.
    \18\ Letter from Richard H. Opper, Director, Montana Department 
of Environmental Quality to Laurel Dygowski, EPA Region 8 Air 
Program, June 19, 2006.
    \19\ Several parties petitioned the Ninth Circuit Court of 
Appeals to review the EPA's NOX and SO2 BART 
determinations at the power plants, Colstrip and Corette (PPL 
Montana, LLC, the National Parks Conservation Association, Montana 
Environmental Information Center, and the Sierra Club). The court 
vacated the NOX and SO2 BART emission limits 
at Colstrip Units 1 and 2 and Corette and remanded those portions of 
the FIP back to the EPA for further proceedings. National Parks 
Conservation Association v. EPA, 788 F.3d 1134 (9th Cir. 2015).
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III. Public Comments and EPA Responses

    Our proposed action provided a 45-day public comment period and an 
opportunity to request a public hearing. During this period, we 
received eight comments from the following four commenters: 
NorthWestern Energy (NorthWestern),\20\ Montana Department of 
Environmental Quality (MT DEQ) \21\ Oldcastle Materials Cement Holdings 
(Oldcastle; through Bison Engineering, Inc.),\22\ and an anonymous 
public comment. We did not receive a request to hold a public hearing. 
The comments

[[Page 42741]]

discussed portions of the proposal regarding the Trident cement kiln 
and Blaine County #1 Compressor station; we did not receive any 
comments on our proposed correction for PM compliance determinations 
for EGUs and cement kilns.
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    \20\ Letter dated May 12, 2017, from Elizabeth Stimatz to Docket 
ID No. EPA-R08-OAR-2017-0062.
    \21\ Letter dated May 30, 2017, from David L. Klemp to Docket ID 
No. EPA-R08-OAR-2017-0062.
    \22\ Letter dated May 28, 2017, from Kevin M. Mathews, Bison 
Engineering, Inc, on behalf of Oldcastle Materials Cement Holdings 
to EPA, Region 8, Office of Air and Radiation.
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    Comment: NorthWestern agreed with us that the Q/D ratio used to 
determine that the Blaine County #1 Compressor Station was subject to 
reasonable progress requirements, where ``Q'' represents actual 
NOX + SO2 emissions in tons per year (tpy) and 
``D'' represents the distance in kilometers from the Blaine County #1 
Compressor Station to the nearest Class I area, was incorrect as 
published in our 2012 final rule. Specifically, Northwestern agrees 
that ``D'' should be 133 kilometers instead of 107 kilometers, and that 
the revised Q/D ratio would be below the threshold for further 
evaluation for reasonable progress controls. As such, explained 
NorthWestern, it is only appropriate that the reasonable progress 
requirement of a NOX emission limit of 21.8 lb/hr (average 
of three stack test runs) as well as the corresponding compliance date, 
test method, monitoring, recordkeeping and reporting requirements for 
the Blaine County #1 Compressor Station be removed from the FIP. 
Additionally, NorthWestern contends that NOX + 
SO2, or ``Q'', should be 745 tpy instead of 1,155 tpy with 
acknowledgement that this revision may not affect the EPA's 
determination that the Blaine County #1 Compressor Station should be 
removed from the reasonable progress emission limit.
    Response: We acknowledge NorthWestern's support for our correction 
to ``D'' in the Q/D ratio for the Blaine County #1 Compressor Station 
that would effectively remove the source from reasonable progress 
NOX requirements for the first implementation period of the 
RHR. We also agree with NorthWestern that a revision to ``Q'' from 
1,155 tpy to 745 tpy will not affect our determination that the Blaine 
County #1 Compressor Station should be removed from the reasonable 
progress limit; therefore, we are not addressing the issue of whether 
``Q'' should be 745 tpy, as opposed to 1,155 tpy.
    Comment: An anonymous commenter stated that the use of Q/D to 
measure the emissions of NOX and SO2 is 
efficient; however, ``D'' can be calculated mistakenly which could 
ultimately affect the decision-making related to further investigation 
or evaluation.
    Response: We agree with the commenter's assertions that using an 
incorrect distance (D) can adversely impact decision making concerning 
further evaluation of a source.
    Comment: MT DEQ expressed support for our proposal to amend the FIP 
before the compliance dates for the two affected facilities and 
appreciated our consideration of input from regulated facilities in 
Montana. MT DEQ also noted that they are working closely with EPA staff 
to submit a regional haze SIP as soon as practicable.
    Response: We acknowledge MT DEQ's support for our action and will 
continue working with MT DEQ as they develop a regional haze SIP.
    Comment: Oldcastle advocated a BART emission limit of 8.3 lb 
NOX/ton clinker for the Trident kiln, as opposed to the 
limit proposed by the EPA of 7.6 lb/ton clinker (both as 30-day rolling 
averages). Oldcastle derived their proposed emission limit from a 
projected control efficiency of 40% when applied to a baseline emission 
rate of 13.9 lb/ton clinker (that is, 13.9 lb/ton clinker x [1 - 40/
100] = 8.3 lb/ton clinker).
    Response: We maintain that the appropriate BART emission limit for 
the Trident kiln is 7.6 lb NOX/ton clinker. In comparison to 
Oldcastle, we derived our proposed emission limit from the same 
projected control efficiency of 40%, but applied the control efficiency 
to a lower baseline emission rate of 12.6 lb/ton clinker (that is, 12.6 
lb/ton clinker x [1 - 40/100] = 7.6 lb/ton clinker). Therefore, the 
proposed emission limits differ only because of the different baseline 
emission rates used to calculate them. We address the question of the 
baseline emission rate in a separate response.
    The proposed emission limit for the Trident kiln of 7.6 lb/ton 
clinker is nearly equal to that for the Ash Grove Montana City kiln of 
7.5 lb/ton clinker established through a control technology 
demonstration.\23\ The Montana City kiln is of the same general design 
(long wet kiln) as the Trident kiln, operates in a similar environment, 
and is a direct competitor in the regional cement market. While the 
ultimate emission limit for the Montana City kiln was set through a 
control technology demonstration, rather than a BART determination, it 
is a reflection of the level of NOX control that is feasible 
with SNCR.\24\ Moreover, as discussed in a later response, the two 
kilns have similar baseline emissions. Accordingly, we find that it is 
reasonable to expect a similar level of controlled NOX 
emissions from the Trident kiln when equipped with SNCR.
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    \23\ EPA letter to Ash Grove Cement Co., December 29, 2016.
    \24\ Prior to the control technology demonstration, the EPA 
established a NOX BART emission limit of 8.0 lb/ton 
clinker for the Montana City kiln.
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    As stated in our proposed rule, it is challenging to predict the 
performance of SNCR for long cement kilns. For this reason, in the 
proposed rule, the EPA invited comment on whether, in place of the BART 
emission limit of 7.6 lb NOX/ton clinker, the emission limit 
for the Trident kiln should be established through a control technology 
demonstration in a manner similar to that required by consent decrees 
for the Ash Grove Montana City kiln and other long kilns. Such an 
approach would have served to demonstrate with some clarity the 
NOX emission limit for the Trident kiln. As discussed in a 
later response, Oldcastle strongly felt that a requirement to use this 
approach was unnecessary. In the absence of support for a control 
technology demonstration from Oldcastle, or from other commenters, and 
for reasons stated elsewhere in response to comments, the EPA is 
finalizing an emission limit of 7.6 lb/ton clinker.
    Comment: Oldcastle agreed with the EPA's assessment in the proposed 
rule that SNCR is theoretically capable of reducing NOX 
emissions from a long wet cement kiln by 40% on average. Oldcastle also 
recognized that the EPA largely based this assumption on the 
performance of SNCR demonstrated at the long wet kiln located at the 
Ash Grove Montana City facility.
    Response: The 40% reduction is a demonstrated, rather than 
theoretical, control effectiveness for SNCR when applied to long cement 
kilns. As acknowledged by the commenter, this level of control was 
demonstrated at the Montana City long wet kiln in association with a 
control technology demonstration.
    Moreover, in arriving at an assumed control effectiveness of 40%, 
the EPA's conclusions were not strictly based on the performance of 
SNCR at the Montana City kiln. As explained in the proposal, we also 
re-evaluated the performance of SNCR at the three Ash Grove long wet 
kilns in Midlothian, Texas, that served as the basis for the emission 
limit for Trident in our 2012 final rule. In addition, we reviewed the 
performance of SNCR at several LaFarge kilns subject to control 
technology demonstrations. The EPA's evaluation of the control 
effectiveness of SNCR when applied to long cement kilns is further 
discussed in the Technical

[[Page 42742]]

Support Document (TSD) associated with this rulemaking.\25\
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    \25\ Refer to Technical Support Document--Oldcastle Trident 
Federal Implementation Plan Revision, March 8, 2017 (``TSD for 
Oldcastle''; EPA docket ID EPA-R08-OAR-2017-0062-0042).
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    Comment: Oldcastle disagreed with the baseline emission rate of 
12.6 lb/ton clinker (as the 99th percentile 30-day rolling average) 
that, after a 40% NOX reduction with SNCR, the EPA used to 
calculate the proposed emission limit of 7.6 lb/ton clinker. Oldcastle 
stated that the appropriate baseline emission rate is 13.9 lb/ton 
clinker, reflecting a period during late 2012 during which optimal 
conditions were disrupted by ash ring build-up on the interior wall of 
the kiln, leading to elevated NOX emissions. Oldcastle also 
disagreed with the EPA's characterization of operations during late 
2012 as resulting from ``exceptional circumstances'' that should be 
excluded from the calculation of baseline emissions, and with the EPA's 
statements in the proposed rule that such conditions could be avoided 
by proper kiln operation and maintenance. Oldcastle stated that ash 
rings are part of normal long-term operations and occur approximately 
twice every year. Finally, in response to the EPA's statements in the 
proposal that a violation of the emission limit could be prevented by 
shutting down the kiln to remove ash rings, Oldcastle commented that 
multiple factors (e.g., such as harm to the kiln, baghouse, and other 
equipment) must be considered before performing an unplanned shutdown. 
Oldcastle commented that if elevated NOX emissions do occur 
as the result of ash ring build-up, an unplanned shut down could be 
required purely to ensure compliance with the emission limit.
    Response: We disagree that the appropriate baseline emission rate 
for the purpose of calculating the NOX emission limit should 
be 13.9 lb/ton clinker. In our proposed rule, we explained the reasons 
for retaining the baseline emission rate of 12.6 lb/ton from the 2012 
rule.26 27 Much of that explanation was in response to a 
letter submitted by Oldcastle (through Bison Engineering) and dated 
February 13, 2017, that among other things addressed the baseline 
emission rate. Oldcastle's comments on the proposed rule largely repeat 
points made in their February 13, 2017 letter, and do not present new 
information that the EPA did not address in the proposed rule, or that 
would lead the EPA to choose a different baseline emission rate (and 
thereby a different emission limit). As such, in responding to 
Oldcastle's comments here, we repeat much of the discussion from our 
proposed rule.
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    \26\ The original source of the 12.6 lb/ton clinker was a 
submittal from the previous owner of the Trident facility, Holcim, 
Inc. See footnote 93 in 2012 proposed rule at 77 FR 24019.
    \27\ See proposed rule at 82 FR 17953/4.
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    In order to determine a representative baseline NOX 
emissions rate for the Trident kiln, the EPA reviewed nine years of 
actual emissions data (2008-2016, as the 99th percentile 30-day rolling 
average).\28\ This expanded on the period of actual emissions data used 
to set the baseline in the 2012 rule, which was limited to 2008-2011.
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    \28\ See TSD for Oldcastle, pages 8-10.
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    The EPA recognizes that ash rings are part of normal long-term 
operations for long kilns, and thus the BART emission limit should, 
generally speaking, allow operation of a kiln while a typical ash ring 
is present, provided that the SNCR system is reducing emissions during 
the ash ring event as much as it reasonably can. Accordingly, the EPA 
has considered the ash ring issue when establishing the single value of 
the baseline emission rate upon which the BART emission limit is based.
    The original emissions baseline period of 2008-2011 used in the 
2012 FIP, together with the emissions for 2013 through 2016, yield 
eight years of emissions data in support of the 12.6 lb/ton clinker 
baseline used by the EPA.\29\ Assuming, as asserted by Oldcastle, that 
ash rings occur approximately twice per year, some 16 ash ring events 
can be statistically expected to have occurred during this eight-year 
period.
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    \29\ The baseline periods of 2008-2011 and 2013-2016 yield an 
identical baseline emission rate of 12.6 lb/ton clinker (as the 99th 
percentile 30-day rolling average). Data for 2012, while reviewed, 
was not included in the calculation of the baseline due to the 
unusually elevated NOX emissions that occurred late in 
that year.
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    From the set of approximately 2,400 values for 30-day average 
emission during the eight-year period,\30\ the EPA has chosen the 99th 
percentile value, 12.6 lb/ton clinker, as the baseline emission rate 
for setting the BART emission limit (by reducing this value by 40%). We 
believe this is a reasonable choice in that it will mean that for most 
ash ring events compliance with the BART emissions limit would not 
necessitate removing the ash ring earlier than when the kiln operators 
have seen fit to remove similar ash rings during the eight years of 
operation of the kiln. Oldcastle is arguing that the baseline emission 
rate should instead be set at 13.9 lb/ton of clinker. Notably, there 
were about 29 30-day average emission values above 13.9 lb/ton during 
the 2012 ash ring event. Under both the emission limit we proposed and 
the emission limit favored by Oldcastle, if an ash ring similar to the 
2012 event were to occur in the future, the BART emission limit could 
not be met merely by achieving 40% emission reductions via SNCR. Thus, 
Oldcastle and we agree that not every ash ring event must be 
accommodated by the BART emission limit, and Oldcastle and we agree 
that Oldcastle should be expected to intervene, differently than the 
kiln operator actually did in 2012, if an event like the one that 
occurred in 2012 occurs again (while also applying SNCR). Where 
Oldcastle and we disagree is that Oldcastle favors a higher BART limit 
that would allow Oldcastle to take no action, which is different from 
the operator's past ash ring-correcting practices with respect to ash 
ring events that have more moderate effects on emissions than the 2012 
ash ring event. While we do not have clear evidence of whether and when 
such more moderate ash rings events have occurred in the past and what 
effects they had on NOX emissions, it reasonable to predict 
that in the future there may be events for which our proposed emission 
limit would require corrective action (beyond the application of SNCR) 
that is different than the operator's ash ring-correcting practices of 
the past, while the emission limit favored by Oldcastle would not 
require this. The considerations on how to respond to Oldcastle's 
comments on this issue are discussed in more detail in the paragraphs 
that follow.
---------------------------------------------------------------------------

    \30\ Does not include days when the kiln was not operated.
---------------------------------------------------------------------------

    The representativeness of the baseline NOX emission rate 
of 12.6 lb/ton clinker used for setting the emission limit at the 
Trident kiln is supported by the nearly identical emissions observed at 
the Montana City kiln in association with the control technology 
demonstration. During the baseline collection period for the Montana 
City kiln, between March and August 2014, the 99th percentile 30-day 
rolling average emission rate without SNCR applied was 12.8 lb 
NOX/ton clinker.\31\ Though this represents a shorter 
baseline period than that considered for Trident, it reinforces that 
the two kilns should be subject to similar emission limits after being 
equipped with SNCR. By contrast, using the higher baseline emission 
rate of 13.9 lb/ton clinker for Trident would result in a relatively 
large difference between the emission limits--7. 5 lb/ton clinker

[[Page 42743]]

for Montana City, and 8.3 lb/ton clinker for Trident.
---------------------------------------------------------------------------

    \31\ See spreadsheet titled ``Summary of Ash Grove Montana City 
Control Technology Demonstration Data.xlsx,'' March 8, 2017, 
prepared by the EPA.
---------------------------------------------------------------------------

    Moreover, if the EPA were to use the higher baseline emission rate 
of 13.9 lb/ton clinker (again yielding an emission limit of 8.3 lb/ton 
clinker at a 40% reduction with SNCR), then the emission limit would be 
overly lenient during periods of otherwise normal kiln operation, and 
the SNCR could be operated at efficiencies well below the demonstrated 
level of control effectiveness. That is, when baseline emissions are at 
otherwise normal levels, the control effectiveness of the SNCR could be 
reduced below the level at which it is capable of performing by 
reducing the amount of reagent injected into the kiln, while still 
meeting the emission limit. For example, consider if SNCR had been 
operated in 2016, the last full year for which emissions data is 
available, where the uncontrolled 30-day rolling average emissions 
ranged from 8.9 to 12.6 lb/ton clinker, with an average of 10.4 lb/ton 
clinker.\32\ At an emission limit of 8.3 lb/ton clinker (corresponding 
to a 13.9 lb/ton clinker baseline), and depending on the 30-day period, 
the SNCR could have been operated at a control efficiency of 6.7% to 
34.1%, and at an average of only 20.5%. Indeed, for long periods, the 
SNCR could have been operated well below the 40% reduction that the EPA 
has concluded, and Oldcastle has agreed, SNCR can achieve. Though this 
opportunity to operate the SNCR system at a lesser level of 
effectiveness would also occur at the proposed emission limit of 7.6 
lb/ton, it would occur less frequently and the effect would be much 
less pronounced, yet the proposed emission limit of 7.6 lb/ton still 
allows for normal variation in uncontrolled NOX emissions 
(to include emissions variation due to ash ring formation). In essence, 
allowing for the higher baseline advocated by the commenter would 
unnecessarily undermine the basic intent of the BART controls: To lower 
emissions that impact visibility using the best available control 
technology.
---------------------------------------------------------------------------

    \32\ See spreadsheet titled ``Oldcastle Trident NOX 
emissions 2008 through 2016 with additions by EPA.xlsx,'' March 8, 
2017, prepared by the EPA (EPA docket ID EPA-R08-OAR-2017-0062-
0039).
---------------------------------------------------------------------------

    In conclusion, the EPA's thorough consideration of nine years of 
actual emissions data and the application of a 40% reduction to the 
99th percentile value of the historical set of 30-day average emission 
values, leads to an appropriate BART emission limit for the Trident 
kiln.
    Comment: Oldcastle stated that the EPA's proposed BART 
determination of 7.6 lb/ton clinker did not address control costs or 
visibility improvement. They commented that, based on their updated 
analysis,\33\ the costs associated with the emission limit are not 
justified by the visibility benefits.
---------------------------------------------------------------------------

    \33\ Oldcastle is referring to submittals to the EPA that were 
cited in the proposed rule. See footnote 22 at 82 FR 17952. These 
submittals can be found in the docket.
---------------------------------------------------------------------------

    Response: We disagree with the implication that it was necessary to 
re-weigh the costs and visibility benefits of SNCR in this action, 
which was not a new or updated control technology determination but 
rather a revision to how the EPA calculated the ultimate emission limit 
given the technology selected pursuant to our previous five-factor 
analysis. See 82 FR 17948, 17951. The BART Guidelines provide that 
states or the EPA, when evaluating technically feasible technologies 
pursuant to a five-factor analysis, perform the analysis ``tak[ing] 
into account the most stringent emission control level that the 
technology is capable of achieving.'' 40 CFR part 51, appendix Y, 
IV.D.1. The Guidelines further state that the control effectiveness of 
a technology should be informed by, among other things, recent 
regulatory decisions, engineering estimates, and the experience of 
other sources. Id. The EPA determined in 2012 that BART is based on 
SNCR with a 50% control effectiveness for the Trident kiln, see 77 FR 
57864, 57882. No party requested judicial review of that determination. 
However, since the time of our 2012 rule, sources and the EPA have 
gained further experience related to using SNCR to control 
NOX from long wet kilns; and additional data and experience 
indicate that the most stringent level of emission control possible 
under these circumstances may not be 50%, as previously assumed. 
However, as Oldcastle assured the EPA when they first approached us to 
request a revised NOX emission limit for the Trident kiln in 
May 2016 and throughout the process of revising the emission limit, 
they are committed to installing and operating SNCR on the kiln.\34\ 
Most recently, Oldcastle restated their commitment to doing so in 
comments on the proposed rule.\35\ For this reason, and as we stated in 
the proposed rule, the EPA did not find it necessary or appropriate to 
revisit the selection of SNCR as the BART control technology was 
determined in the 2012 rule.
---------------------------------------------------------------------------

    \34\ See, e.g., Letter dated Sept. 30, 2016, from Kevin M. 
Mathews, Bison Engineering, Inc. on behalf of Oldcastle Materials 
Cement Holdings to EPA, Region 8, Office of Air and Radiation, pages 
2, 6, 19.
    \35\ Letter dated May 28, 2017, from Kevin M. Mathews, Bison 
Engineering, Inc, on behalf of Oldcastle Materials Cement Holdings 
to EPA, Region 8, Office of Air and Radiation, page 3.
---------------------------------------------------------------------------

    Additionally, given that Oldcastle has committed to the most 
effective control technology for long kilns, SNCR, and in fact had 
largely completed construction by the time we published the proposed 
rule in April 2017, there would be little merit in retrospectively 
assessing less effective control technologies in an updated five-factor 
BART analysis. The BART Guidelines reflect that it is reasonable, if a 
source has already committed to a BART determination that consists of 
the most stringent controls available, to forgo completing the 
remaining analyses pursuant to a BART determination. 40 CFR part 51, 
appendix Y, IV.D.1. Oldcastle has communicated to the EPA that it is 
committed to installing and operating SNCR on the Trident kiln. 
Therefore, consistent with the reasoning of the BART Guidelines, we 
found that it is not necessary in this instance to revisit the cost 
effectiveness and visibility benefits associated with SNCR, and instead 
as explained in our proposal, constrained this FIP revision to 
considering only the appropriate control effectiveness associated with 
that control technology.
    Because Oldcastle has committed to installing SNCR as the BART 
control, it is only the emission limit that is in dispute. However, 
even if we had revisited the full five-factor BART analysis in this 
action, it is very likely we would have arrived at the same emission 
limit we are finalizing today. The 2012 rule established an emission 
limit of 6.5 lb/ton clinker, while we have proposed 7.6 lb/ton clinker, 
and Oldcastle advocates for 8.3 lb/ton clinker. Note that compliance 
with a more stringent emission limit requires that more reagent be 
injected into the kiln to reduce NOX than for a less 
stringent emission limit, thereby increasing Oldcastle's annual costs 
to operate the SNCR. Though annual costs would increase with a more 
stringent emission limit, NOX reductions can generally be 
expected to increase in proportion to those costs. An exception is if 
the amount of reagent injected is increased to the point that it is no 
longer effective at reducing NOX and leads to excessive 
ammonia slip (that is, wasted reagent). However, as demonstrated at the 
Montana City kiln, a 40% reduction in NOX, which serves as 
the basis for Trident's emission limit, can be achieved at acceptable 
levels of ammonia slip.\36\ Therefore, the cost effectiveness of SNCR, 
when calculated as the costs per ton of pollutant

[[Page 42744]]

removed (i.e., $/ton) in accordance with the BART Guidelines,\37\ would 
be roughly the same at any of the three emission limits under 
consideration.\38\ Further, due to the increase in NOX 
reductions, greater visibility benefits would be expected to occur as 
the emission limit becomes more stringent. Because the cost 
effectiveness would remain roughly constant, while the visibility 
benefits would increase, we see no reason that the SNCR should be 
operated below the level of control effectiveness demonstrated for the 
technology (i.e., a 40% NOX reduction). Therefore, we are 
finalizing an emission limit for the Trident kiln consistent with that 
level of control: 7.6 lb/ton clinker.
---------------------------------------------------------------------------

    \36\ Refer to proposed rule at 71 FR 17953.
    \37\ 70 FR 39167.
    \38\ More precisely, the cost effectiveness (as $/ton) would 
slightly decrease in value at a more stringent emission limit 
because the fixed capital costs would be distributed over a greater 
number of tons of NOX reduced.
---------------------------------------------------------------------------

    Comment: Oldcastle commented that they strongly feel that a 
requirement to conduct a control technology demonstration, such as that 
conducted for the Ash Grove Montana City kiln under consent decree, is 
problematic and unnecessary. Further, they commented that if such a 
control technology demonstration were to be conducted, the results 
would likely be similar to those for the Montana City kiln. Finally, 
Oldcastle stated that a control technology demonstration would not 
address the economic and operational concerns (e.g., ash rings) that 
they also raised in comments.
    Response: Because Oldcastle, or other commenters, have not 
expressed support for a control technology demonstration, and because 
the results from the Montana City kiln demonstration can effectively 
and reasonably be applied to the Trident kiln, we are not requiring 
such a demonstration for the Trident kiln. Instead, we are finalizing 
an emission limit of 7.6 lb/ton clinker.

IV. Final Action

    The EPA is taking final action to revise portions of the Montana 
Regional Haze FIP. Specifically, the EPA is revising the BART 
NOX emission limit in the second line of the table in 40 CFR 
52.1396(c)(2) for the Oldcastle Trident kiln from 6.5 lb 
NOX/ton clinker to 7.6 lb NOX/ton clinker (30-day 
rolling averages).\39\ We are also making two corrections: (1) Removing 
the reasonable progress NOX emission limit of 21.8 lb/hr 
(average of three stack test runs) found at 40 CFR 52.1396(c)(3) for 
the Blaine County #1 Compressor Station, Engine #1 and #2, including 
removing the corresponding compliance date at 40 CFR 52.1396(d), test 
method (40 CFR 52.1396(e)(5)), testing requirements (40 CFR 52.1396(j)) 
and monitoring, recordkeeping, and reporting requirements found at 40 
CFR 52.1396(k) from the FIP, and (2) revising the regulatory text found 
at 40 CFR 52.1396(f)(1) and (2) related to compliance determinations 
for particulate matter for electrical generating units and cement 
kilns. Finally, we are changing ``Holcim'' references to ``Oldcastle'' 
and ``Trident'' at 40 CFR 52.1396(a), (c)(2), and (f)(2)(ii) and 
replacing the compliance date timeframes in 40 CFR 52.1396(d) with the 
actual compliance dates based on the effective date of the 2012 FIP.
---------------------------------------------------------------------------

    \39\ The table in 40 CFR 52.1396(c)(2) currently refers to 
Holcim (US) Inc. As described later on, the EPA is also updating 
this table to reflect the Trident kiln's new ownership.
---------------------------------------------------------------------------

    We find that the revisions will not interfere with any applicable 
requirement concerning attainment, reasonable progress, or any other 
applicable requirement of the CAA, because the FIP, as revised by this 
action, will result in a significant reduction in emissions compared to 
current levels. Although this revision will allow an increase in 
emissions after October 2017 as compared to the prior FIP, the FIP as a 
whole will still result in overall NOX and SO2 
reductions compared to those currently allowed. In addition, the areas 
where the Trident cement kiln and the Blaine County #1 Compressor 
Station are located have not been designated nonattainment for any 
National Ambient Air Quality Standards (NAAQS). We also find that we 
satisfied the applicable requirements for coordination and consultation 
with the Federal Land Managers (FLMs) because we described the proposed 
revisions to the regional haze FIP with the Forest Service, the Fish 
and Wildlife Service and the National Park Service on Thursday, March 
2, 2017, and sent a draft of our proposed regional haze FIP revisions 
to the Forest Service, the Fish and Wildlife Service and the National 
Park Service on March 9, 2017.\40\
---------------------------------------------------------------------------

    \40\ We did not receive any formal comments from the FLM 
agencies.
---------------------------------------------------------------------------

V. Statutory and Executive Order Reviews

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

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

    This action is not a ``significant regulatory action'' under the 
terms of Executive Order 12866 \41\ and was therefore not submitted to 
the Office of Management and Budget (OMB) for review. This final rule 
revision applies to only five facilities in the State of Montana. It is 
therefore not a rule of general applicability.
---------------------------------------------------------------------------

    \41\ 58 FR 51735, 51738 (October 4, 1993).
---------------------------------------------------------------------------

B. Executive Order 13711: Reducing Regulation and Controlling 
Regulatory Costs

    This action is not expected to be an Executive Order 13771 action 
because it is not subject to Executive Order 12866.

C. Paperwork Reduction Act

    This action does not impose an information collection burden under 
the provisions of the Paperwork Reduction Act (PRA).\42\ Because this 
final rule revises the reporting requirements for 4 facilities and 
removes all requirements for an additional facility, the PRA does not 
apply.
---------------------------------------------------------------------------

    \42\ 44 U.S.C. 3501 et seq.
---------------------------------------------------------------------------

D. Regulatory Flexibility Act

    I certify that this action will not have a significant economic 
impact on a substantial number of small entities under the RFA. This 
rule does not impose any requirements or create impacts on small 
entities as no small entities are subject to the requirements of this 
rule.

E. 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, and does not 
significantly or uniquely affect small governments. The revisions to 
the FIP reduce private sector expenditures. Additionally, we do not 
foresee significant costs (if any) for state and local governments.

F. Executive Order 13132: Federalism

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

[[Page 42745]]

G. Executive Order 13175: Consultation and Coordination With Indian 
Tribal Governments

    This action does not have tribal implications, as specified in 
Executive Order 13175. It will not have substantial direct effects on 
tribal governments. Thus, Executive Order 13175 does not apply to this 
rule. However, the EPA did send letters to each of the Montana tribes 
explaining our regional haze FIP revision action and offering 
consultation; however, no tribe asked for consultation.

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

    This action is not subject to Executive Order 13045 (62 FR 19885, 
April 23, 1997). 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.

I. Executive Order 13211: Actions Concerning Regulations That 
Significantly Affect Energy Supply, Distribution, or Use

    This action is not subject to Executive Order 13211 (66 FR 28355 
(May 22, 2001)), because it is not a significant regulatory action 
under Executive Order 12866.

J. National Technology Transfer and Advancement Act

    This rulemaking does not involve technical standards.

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

    The EPA believes that this action does not have disproportionately 
high and adverse human health or environmental effects on minority 
populations, low-income populations and/or indigenous peoples, as 
specified in Executive Order 12898 (59 FR 7629, February 16, 1994). As 
explained previously, the Montana Regional Haze FIP, as revised by this 
action, will result in a significant reduction in emissions compared to 
current levels.

L. Congressional Review Act (CRA)

    This rule is exempt from the CRA because it is a rule of particular 
applicability.

M. Judicial Review

    Under section 307(b)(1) of the CAA, petitions for judicial review 
of this action must be filed in the United States Court of Appeals for 
the appropriate circuit by November 13, 2017. Pursuant to CAA section 
307(d)(1)(B), this section is subject to the requirements of the CAA 
section 307(d) as it promulgates a FIP under CAA section 110(c). Filing 
a petition for reconsideration by the Administrator of this final rule 
does not affect the finality of this action for purposes of judicial 
review nor does it extend the time within which a petition for judicial 
review may be filed, and shall not postpone the effectiveness of such 
rule or action. This action may not be challenged later in proceedings 
to enforce its requirements. See CAA section 307(b)(2).

List of Subjects in 40 CFR Part 52

    Environmental protection, Air pollution control, Incorporation by 
reference, Intergovernmental relations, Nitrogen dioxide, Particulate 
matter, Sulfur oxides.

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

    Dated: September 1, 2017.
E. Scott Pruitt,
Administrator.

    40 CFR part 52 is amended as follows:

PART 52--APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS

0
1. The authority citation for part 52 continues to read as follows:

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

Subpart BB--Montana

0
2. Section 52.1396 is amended by:
0
a. Revising paragraph (a);
0
b. Revising paragraph (c)(2);
0
c. Removing and reserving paragraph (c)(3);
0
d. Revising paragraph (d);
0
e. Removing paragraph (e)(5);
0
f. Revising the heading of paragraph (f) and paragraphs (f)(1), (f)(2) 
introductory text, and (f)(2)(ii); and
0
g. Removing and reserving paragraphs (j) and (k).
    The revisions read as follows:

Sec.  52.1396  Federal implementation plan for regional haze.

    (a) Applicability. This section applies to each owner and operator 
of the following coal-fired electric generating units (EGUs) in the 
State of Montana: PPL Montana, LLC, Colstrip Power Plant, Units 1, 2; 
and PPL Montana, LLC, JE Corette Steam Electric Station. This section 
also applies to each owner and operator of cement kilns at the 
following cement production plants: Ash Grove Cement, Montana City 
Plant; and Oldcastle Materials Cement Holdings, Inc., Trident Plant. 
This section also applies to each owner and operator of CFAC and M2 
Green Redevelopment LLC, Missoula site.

    Note to Paragraph (a):  On June 9, 2015, the NOX and 
SO2 emission limits for Colstrip Units 1 and 2 and 
Corette were vacated by court order.

* * * * *
    (c) * * *
    (2) The owners/operators of cement kilns subject to this section 
shall not emit or cause to be emitted PM, SO2 or 
NOX in excess of the following limitations, in pounds per 
ton of clinker produced, averaged over a rolling 30-day period for 
SO2 and NOX:

----------------------------------------------------------------------------------------------------------------
                                                                                   SO2 emission    NOX emission
                                                                                   limit (lb/ton   limit (lb/ton
             Source name                           PM emission limit                 clinker)        clinker)
 
----------------------------------------------------------------------------------------------------------------
Ash Grove, Montana City..............  If the process weight rate of the kiln is            11.5             8.0
                                        less than or equal to 30 tons per hour,
                                        then the emission limit shall be
                                        calculated using E = 4.10p\0.67\ where E
                                        = rate of emission in pounds per hour
                                        and p = process weight rate in tons per
                                        hour; however, if the process weight
                                        rate of the kiln is greater than 30 tons
                                        per hour, then the emission limit shall
                                        be calculated using E = 55.0p\0.11\-40,
                                        where E = rate of emission in pounds per
                                        hour and P = process weight rate in tons
                                        per hour..
Oldcastle, Trident...................  0.77 lb/ton clinker......................             1.3             7.6
----------------------------------------------------------------------------------------------------------------

[[Page 42746]]

* * * * *
    (d) Compliance date. The owners and operators of the BART sources 
subject to this section shall comply with the emission limitations and 
other requirements of this section as follows, unless otherwise 
indicated in specific paragraphs: Compliance with PM emission limits is 
required by November 17, 2012. Compliance with SO2 and 
NOX emission limits is required by April 16, 2013, unless 
installation of additional emission controls is necessary to comply 
with emission limitations under this rule, in which case compliance is 
required by October 18, 2017.

    Note to Paragraph (d):  On June 9, 2015, the NOX and 
SO2 emission limits, and thereby compliance dates, for 
Colstrip Units 1 and 2 and Corette were vacated by court order.

* * * * *
    (f) Compliance determinations for particulate matter--(1) EGU 
particulate matter BART emission limits. Compliance with the 
particulate matter BART emission limits for each EGU BART unit shall be 
determined by the owner/operator from annual performance stack tests. 
Within 60 days of the compliance deadline specified in paragraph (d) of 
this section, and on at least an annual basis thereafter, the owner/
operator of each unit shall conduct a stack test on each unit to 
measure the particulate emissions using EPA Method 5, 5B, 5D, or 17, as 
appropriate, in 40 CFR part 60, appendix A. A test shall consist of 
three runs, with each run at least 120 minutes in duration and each run 
collecting a minimum sample of 60 dry standard cubic feet. Results 
shall be reported by the owner/operator in lb/MMBtu. The results from a 
stack test meeting the requirements of this paragraph (f)(1) that was 
completed within 12 months prior to the compliance deadline can be used 
in lieu of the first stack test required. If this option is chosen, 
then the next annual stack test shall be due no more than 12 months 
after the stack test that was used. In addition to annual stack tests, 
owner/operator shall monitor particulate emissions for compliance with 
the BART emission limits in accordance with the applicable Compliance 
Assurance Monitoring (CAM) plan developed and approved in accordance 
with 40 CFR part 64.
    (2) Cement kiln particulate matter BART emission limits. Compliance 
with the particulate matter BART emission limits for each cement kiln 
shall be determined by the owner/operator from annual performance stack 
tests. Within 60 days of the compliance deadline specified in paragraph 
(d) of this section, and on at least an annual basis thereafter, the 
owner/operator of each unit shall conduct a stack test on each unit to 
measure particulate matter emissions using EPA Method 5, 5B, 5D, or 17, 
as appropriate, in 40 CFR part 60, appendix A. A test shall consist of 
three runs, with each run at least 120 minutes in duration and each run 
collecting a minimum sample of 60 dry standard cubic feet. The average 
of the results of three test runs shall be used by the owner/operator 
for demonstrating compliance. The results from a stack test meeting the 
requirements of this paragraph (f)(2) that was completed within 12 
months prior to the compliance deadline can be used in lieu of the 
first stack test required. If this option is chosen, then the next 
annual stack test shall be due no more than 12 months after the stack 
test that was used. Clinker production shall be determined in 
accordance with the requirements found at 40 CFR 60.63(b). Results of 
each test shall be reported by the owner/operator as the average of 
three valid test runs. In addition to annual stack tests, owner/
operator shall monitor particulate emissions for compliance with the 
BART emission limits in accordance with the applicable Compliance 
Assurance Monitoring (CAM) plan developed and approved in accordance 
with 40 CFR part 64.
* * * * *
    (ii) For Trident, the emission rate (E) of particulate matter shall 
be computed by the owner/operator for each run in lb/ton clinker, using 
the following equation:

E = (CsQs)/PK

Where:

E = emission rate of PM, lb/ton of clinker produced;
Cs = concentration of PM in grains per standard cubic 
foot (gr/scf);
Qs = volumetric flow rate of effluent gas, where 
Cs and Qs are on the same basis (either wet or 
dry), scf/hr;
P = total kiln clinker production, tons/hr; and
K = conversion factor, 7,000 gr/lb.
* * * * *
[FR Doc. 2017-19210 Filed 9-11-17; 8:45 am]
 BILLING CODE 6560-50-P