Document ID: EPA-HQ-OAR-2015-0531-0001
Agency: epa
Document Type: Proposed Rule
Title: Protection of Visibility; Amendments to Requirements for State Plans
Posted Date: 2016-05-04T04:00Z

[Federal Register Volume 81, Number 86 (Wednesday, May 4, 2016)]
[Proposed Rules]
[Pages 26941-26976]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2016-10228]

[[Page 26941]]

Vol. 81

Wednesday,

No. 86

May 4, 2016

Part IV

Environmental Protection Agency

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40 CFR Parts 51 and 52

 Protection of Visibility: Amendments to Requirements for State Plans; 
Proposed Rule

  Federal Register / Vol. 81 , No. 86 / Wednesday, May 4, 2016 / 
Proposed Rules  

[[Page 26942]]

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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Parts 51 and 52

[EPA-HQ-OAR-2015-0531; FRL-9935-27-OAR]
RIN 2060-AS55

Protection of Visibility: Amendments to Requirements for State 
Plans

AGENCY: Environmental Protection Agency (EPA).

ACTION: Proposed rule.

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SUMMARY: The Environmental Protection Agency (EPA) is proposing 
amendments to requirements under the Clean Air Act (CAA) for state 
plans for protection of visibility in mandatory Class I federal areas 
(Class I areas) in order to continue steady environmental progress 
while addressing administrative aspects of the program. The EPA 
amendments would clarify the relationship between long-term strategies 
and reasonable progress goals in state plans, and the long-term 
strategy obligation of all states. The amendments would also change the 
way in which some days during each year are to be selected for purposes 
of tracking progress towards natural visibility conditions to account 
for events such as wildfires; change aspects of the requirements for 
the content of progress reports; update, simplify and extend to all 
states the provisions for reasonably attributable visibility impairment 
and revoke existing federal implementation plans (FIPs) that require 
the EPA to assess and address any existing reasonably attributable 
visibility impairment situations in some states; and add a requirement 
for states to consult with Federal Land Managers (FLMs) earlier in the 
development of state plans. The EPA also proposes to address 
administrative aspects of the program by making a one-time adjustment 
to the due date for the next state implementation plans (SIPs), 
revising the due dates for progress reports and removing the 
requirement for progress reports to be SIP revisions.

DATES: Comments. Written comments on this proposal must be received on 
or before July 5, 2016. Public hearing. The EPA is holding a public 
hearing concerning the proposed rule on May 19, 2016, in Washington, 
DC. The last day to pre-register to speak at the hearing is May 17, 
2016. Please refer to SUPPLEMENTARY INFORMATION for additional 
information on submitting comments and the public hearing. Information 
collection request. Under the Paperwork Reduction Act (PRA), comments 
on the information collection provisions are best assured of having 
full effect if the Office of Management and Budget (OMB) receives a 
copy of your comments on or before June 3, 2016.

ADDRESSES: Comments: Submit your comments, identified by Docket ID No. 
EPA-HQ-OAR-2015-0531, at http://www.regulations.gov. Follow the online 
instructions for submitting comments. Once submitted, comments cannot 
be edited or removed from Regulations.gov. 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, 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/comments.html. Public hearing: A public hearing 
will be held at William Jefferson Clinton East building (WJC East), 
Room 1117A, in Washington, DC. Identification is required. If your 
driver's license is issued by American Samoa, Illinois or Missouri, you 
must present an additional form of identification to enter. Enhanced 
driver's licenses from Minnesota and Washington are acceptable. Please 
refer to SUPPLEMENTARY INFORMATION for additional information on the 
public hearing and location requirements.

FOR FURTHER INFORMATION CONTACT: For general information on this 
proposed rule and Information Collection Request (ICR), contact Mr. 
Christopher Werner, Office of Air Quality Planning and Standards, U.S. 
Environmental Protection Agency, by phone at (919) 541-5133 or by email 
at werner.christopher@epa.gov; or Ms. Rhea Jones, Office of Air Quality 
Planning and Standards, U.S. Environmental Protection Agency, by phone 
at (919) 541-2940 or by email at jones.rhea@epa.gov. For information on 
the public hearing or to register to speak at the hearing, contact Ms. 
Pamela Long, Office of Air Quality Planning and Standards, U.S. 
Environmental Protection Agency, by phone at (919) 541-0641 or by email 
at long.pam@epa.gov.

SUPPLEMENTARY INFORMATION: 

I. General Information

A. Preamble Glossary of Terms and Acronyms

    The following are abbreviations of terms used in this document.

AQRV Air quality related value
BART Best available retrofit technology
bext Light extinction
CAA Clean Air Act
CFR Code of Federal Regulations
EGU Electric generating unit
EPA Environmental Protection Agency
FIP Federal implementation plan
FLM or FLMs Federal Land Manager or Managers
ICR Information collection request
IMPROVE Interagency monitoring of protected visual environments
NAAQS National ambient air quality standards
NOX Nitrogen oxides
OMB Office of Management and Budget
PM Particulate matter
PM2.5 Particulate matter equal to or less than 2.5 
microns in diameter (fine particulate matter)
PM10 Particulate matter equal to or less than 10 microns 
in diameter
PRA Paperwork Reduction Act
PSD Prevention of significant deterioration
RPO Regional planning organization
SIP State implementation plan
SO2 Sulfur dioxide
TAR Tribal Authority Rule
URP Uniform rate of progress

B. Does this action apply to me?

    Entities potentially affected directly by this proposed rule 
include state, local and tribal \1\ governments, as well as FLMs 
responsible for protection of visibility in mandatory Class I areas. 
Entities potentially affected indirectly by this proposed rule include 
owners and operators of sources that emit particulate matter equal to 
or less than 10 microns in diameter (PM10), particulate 
matter equal to or less than 2.5 microns in diameter (PM2.5 
or fine

[[Page 26943]]

PM), sulfur dioxide (SO2), oxides of nitrogen 
(NOX), volatile organic compounds and other pollutants that 
may cause or contribute to visibility impairment. Others potentially 
affected indirectly by this proposed rule include members of the 
general public who live, work or recreate in mandatory Class I areas 
affected by visibility impairment. Because emission sources that 
contribute to visibility impairment in Class I areas also may 
contribute to air pollution in other areas, members of the general 
public may also be affected by this proposed rulemaking.
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    \1\ The Regional Haze Rule may apply, as appropriate under the 
Tribal Authority Rule (TAR) in 40 CFR part 49, to an Indian tribe 
that receives a determination of eligibility for treatment as a 
state for purposes of administering a tribal visibility protection 
program under section 169A of the CAA. No tribe has applied for such 
status, and so at present the EPA is responsible for implementation 
of the Regional Haze Rule in areas of tribal authority. This 
responsibility includes, but is not limited to, implementation of 
the reasonable progress requirements of 40 CFR 51.308(f) in 
instances where potentially affected sources are located on tribal 
land, as necessary or appropriate. The proposed rule changes may 
impact the development and approvability of tribal implementation 
plans that tribes may wish to develop in the future. We encourage 
states to provide outreach and engage in discussions with tribes 
about their regional haze SIPs as they are being developed.
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C. What should I consider as I prepare my comments for the EPA?

    When submitting comments, remember to:
     Identify the rulemaking docket by docket number and other 
identifying information (subject heading, Federal Register date and 
page number).
     Follow directions. The proposed rule may ask you to 
respond to specific questions or organize comments by referencing a 
Code of Federal Regulations (CFR) part or section number.
     Explain why you agree or disagree, suggest alternatives 
and substitute language for your requested changes.
     Describe any assumptions and provide any technical 
information and/or data that you used to support your comment.
     If you estimate potential costs or burdens, explain how 
you arrived at your estimate in sufficient detail to allow for it to be 
reproduced.
     Provide specific examples to illustrate your concerns 
wherever possible, and suggest alternatives.
     Explain your views as clearly as possible, avoiding the 
use of profanity or personal threats.
     Make sure to submit your comments by the comment period 
deadline identified.
    Please note that this is a narrow proposed rulemaking. Please focus 
your comments on only those sections of the CFR affected by our 
proposed changes.

D. What information should I know about the public hearing?

    The May 19, 2016, public hearing will be held to accept oral 
comments on this proposed rulemaking. The hearing will be held at the 
U.S. Environmental Protection Agency, William Jefferson Clinton East 
Building (WJC East), Room 1117A, 1201 Constitution Avenue NW., 
Washington, DC. It will convene at 9:00 a.m. and continue until the 
earlier of 5:00 p.m. or 1 hour after the last registered speaker has 
spoken. We have scheduled a lunch break from 12:00 to 1:00 p.m. People 
interested in presenting oral testimony should contact Ms. Pamela Long, 
Air Quality Planning Division, Office of Air Quality Planning and 
Standards, U.S. Environmental Protection Agency, Research Triangle 
Park, NC 27711, telephone (919) 541-0641, fax number (919) 541-5509, 
email address long.pam@epa.gov, at least 2 days in advance of the 
public hearing (see DATES). Additionally, requests to speak will be 
taken the day of the hearing at the hearing registration desk, although 
preferences on speaking times may not be able to be fulfilled. 
Depending on the flow of the day, times may fluctuate. People 
interested in attending the public hearing should also call Ms. Long to 
verify the time, date and location of the hearing. While the EPA 
expects the hearing to go forward as set forth, we ask that you monitor 
our Web site at http://www.epa.gov/visibility or contact Ms. Pamela 
Long to determine if there are any updates to the information on the 
hearing.
    Oral testimony will be limited to 5 minutes for each commenter. The 
EPA encourages commenters to provide the EPA with a copy of their oral 
testimony electronically (via email) before the hearing and in hard 
copy form at the hearing.
    The EPA may ask clarifying questions during the oral presentations, 
but will not respond to the presentations at that time. Written 
statements and supporting information submitted during the comment 
period will be considered with the same weight as oral comments and 
supporting information presented at the public hearing. Verbatim 
transcripts of the hearing and written statements will be included in 
the docket for the rulemaking.
    Because this hearing is being held at United States (U.S.) 
government facilities, individuals planning to attend the hearing 
should be prepared to show valid picture identification to the security 
staff in order to gain access to the meeting room. Please note that the 
REAL ID Act, passed by Congress in 2005, established new requirements 
for entering federal facilities. If your driver's license is issued by 
American Samoa, Illinois or Missouri, you must present an additional 
form of identification to enter the federal building. Enhanced driver's 
licenses from Minnesota and Washington are acceptable. Acceptable 
alternative forms of identification include: Federal employee badges, 
passports, enhanced driver's licenses, and military identification 
cards. For additional information for the status of your state 
regarding REAL ID, go to http://www.dhs.gov/real-id-enforcement-brief. 
In addition, you will need to obtain a property pass for any personal 
belongings you bring with you. Upon leaving the building, you will be 
required to return this property pass to the security desk. No large 
signs will be allowed in the building, cameras may only be used outside 
of the building, and demonstrations will not be allowed on federal 
property for security reasons.
    Attendees may be asked to go through metal detectors. To help 
facilitate this process, please be advised that you will be asked to 
remove all items from all pockets and place them in provided bins for 
screening; remove laptops, phones, or other electronic devices from 
their carrying case and place in provided bins for screening; avoid 
shoes with metal shanks, toe guards, or supports as a part of their 
construction; remove any metal belts, metal belt buckles, large 
jewelry, watches, and follow the instructions of the guard if 
identified for secondary screening. Additionally, no weapons or drugs 
or drug paraphernalia will be allowed in the building. We recommend 
that you arrive 20 minutes in advance of your speaking time to allow 
time to go through security and to check in with the registration desk.

E. Where can I obtain a copy of this document and other related 
information?

    In addition to being available in the docket, an electronic copy of 
this Federal Register document will be posted at http://www.epa.gov/visibility.

F. How is this Federal Register document organized?

    The information presented in this document is organized as follows:

I. General Information
    A. Preamble Glossary of Terms and Acronyms
    B. Does this action apply to me?
    C. What should I consider as I prepare my comments for the EPA?
    D. What information should I know about the public hearing?
    E. Where can I obtain a copy of this document and other related 
information?
    F. How is this Federal Register document organized?
II. What action is the EPA proposing to take?
III. What is the background for the EPA's proposed action?
    A. Reasonably Attributable Visibility Impairment
    B. Regional Haze
    1. Requirements of the 1990 CAA Amendments and the EPA's 
Regional Haze Rule
    2. Roles of Agencies in Addressing Regional Haze
    3. Requirements for the Regional Haze SIPs

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    4. Requirements for the Regional Haze Progress Reports
    5. Tribes and Regional Haze
    C. Air Permitting
IV. Proposed Rule Changes
    A. Clarifications To Reflect the EPA's Long-Standing 
Interpretation of the Relationship Between Long-Term Strategies and 
Reasonable Progress Goals
    B. Other Clarifications and Changes to Requirements for Periodic 
Comprehensive Revisions of Implementation Plans
    C. Changes to Definitions and Terminology Related to How Days 
Are Selected for Tracking Progress
    D. Impacts on Visibility From Anthropogenic Sources Outside the 
U.S.
    E. Impacts on Visibility From Wildland Fires Within the U.S.
    F. Clarification of and Changes to the Required Content of 
Progress Reports
    G. Changes to Reasonably Attributable Visibility Impairment 
Provisions
    H. Consistency Revisions Related to Permitting of New and 
Modified Major Sources
    I. Changes to FLM Consultation Requirements
    J. Extension of Next Regional Haze SIP Deadline From 2018 to 
2021
    K. Changes to Scheduling of Regional Haze Progress Reports
    L. Changes to the Requirement that Regional Haze Progress 
Reports Be SIP Revisions
    M. Changes to Requirements Related to the Grand Canyon 
Visibility Transport Commission
V. Environmental Justice Considerations
VI. Statutory and Executive Order Reviews
    A. Executive Order 12866: Regulatory Planning and Review and 
Executive Order 13563: Improving Regulation and Regulatory Review
    B. Paperwork Reduction Act (PRA)
    C. Regulatory Flexibility Act (RFA)
    D. Unfunded Mandates Reform Act (UMRA)
    E. Executive Order 13132: Federalism
    F. Executive Order 13175: Consultation and Coordination With 
Indian Tribal Governments
    G. Executive Order 13045: Protection of Children From 
Environmental Health and Safety Risks
    H. Executive Order 13211: Actions Concerning Regulations That 
Significantly Affect Energy Supply, Distribution or Use
    I. National Technology Transfer and Advancement Act
    J. Executive Order 12898: Federal Actions To Address 
Environmental Justice in Minority Populations and Low-Income 
Populations
VII. Statutory Authority

II. What action is the EPA proposing to take?

    The EPA is proposing changes to the requirements that states (and, 
if applicable, tribes) would have to meet as they implement programs 
for the protection of visibility in mandatory Class I areas.\2\ This 
proposal would support continued environmental progress by clarifying 
certain or revising existing regulatory provisions and removing older 
rule provisions that have been superseded by subsequent developments. 
The EPA is proposing to clarify the relationship between long-term 
strategies and reasonable progress goals in state plans and the long-
term strategy obligation of all states. The EPA is also proposing to 
revise the way in which some days during each year are to be selected 
for purposes of tracking progress towards natural visibility conditions 
in order to focus attention on days when anthropogenic emissions impair 
visibility; revise aspects of the requirements for the content of 
progress reports; update, simplify and extend to all states the 
provisions for reasonably attributable visibility impairment and revoke 
existing FIPs that require the EPA to assess and address any existing 
reasonably attributable visibility impairment situations in some 
states; and add a requirement for states to consult with FLMs earlier 
in the development of state plans. Other changes address administrative 
aspects of the program in order to reduce unnecessary burden. 
Specifically, the EPA proposes to make a one-time adjustment to the due 
date for the next SIPs (from 2018 to 2021, which would help states to 
coordinate regional haze planning with that for other programs), to 
revise the due dates for progress reports and to remove the requirement 
for progress reports to be SIP revisions. All of these changes would 
apply to periodic comprehensive state implementation plans developed 
for the second and subsequent implementation periods and for progress 
reports submitted subsequent to those plans. We do not intend the 
proposed changes to affect the development of state plans for the first 
implementation period or the first progress reports due under the 
existing Regional Haze Rule.
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    \2\ Areas designated as mandatory Class I areas consist of 
national parks exceeding 6,000 acres, wilderness areas and national 
memorial parks exceeding 5,000 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, the 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 that 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 action, we mean any 
one of the 156 ``mandatory Class I Federal areas'' where visibility 
has been identified as an important value.
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    The EPA is proposing these changes for several reasons, as 
described more fully in the descriptions of each change detailed later 
in this proposed action. The proposed clarifications regarding the 
relationship between reasonable progress goals, long-term strategies 
and the long-term strategy obligation of all states reflect long-
standing EPA interpretation of the Regional Haze Rule and are intended 
to ensure consistent (and appropriate) understanding of these 
requirements as states prepare their plans for the second 
implementation period. Changes to FLM consultation requirements would 
help ensure that the expertise and perspective of these officials are 
brought into the state plan development process earlier, so that they 
contribute meaningfully during the state's technical analysis and 
deliberations. The proposals related to how days are selected for 
visibility progress tracking would provide the public and state 
officials more meaningful information on how existing and potential new 
emission reduction measures are contributing or could contribute to 
reasonable progress in reducing man-made visibility impairment, by 
greatly reducing the trend-distorting effect of wildfires and natural 
dust storms. Collectively, these changes would serve to strengthen the 
regional haze program based upon lessons learned during the decade and 
a half since the program's inception.
    With regard to the proposed extension of the current deadline of 
July 31, 2018, to July 31, 2021, for states' comprehensive SIP 
revisions for the second implementation period, the EPA believes this 
one-time change would benefit states by allowing them to obtain and 
take into account information on the effects of a number of other 
regulatory programs that will be affecting sources over the next 
several years. The change would also allow states to develop SIP 
revisions for the second implementation period that are more integrated 
with state planning for these other programs, an advantage that was 
widely confirmed in discussions with states and that is anticipated to 
result in greater environmental progress than if planning for these 
multiple programs were not as well integrated. The end date for the 
second implementation period remains 2028, meaning state plans will 
still focus on emission reduction measures designed to achieve 
reasonable progress by 2028,\3\

[[Page 26945]]

as required by the current rule. Other than the proposed one-time 
change to the next due date for periodic comprehensive SIP revisions 
(i.e., for those currently due in 2018), no change is being proposed 
for due dates for future periodic comprehensive SIP revisions.
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    \3\ When considering the ``time necessary for compliance,'' see 
42 U.S.C. 7491(g)(1), a state should account for this factor by 
setting an appropriate compliance schedule. The EPA expects that any 
control measure included in a SIP submitted by the proposed July 31, 
2021, submission deadline will be feasible to implement by 2028.
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    The proposed changes related to progress reports are intended to 
make the timing of progress reports more useful as mid-course reviews, 
to clarify the required content of progress reports for aspects on 
which there has been some ambiguity, and to allow states to conserve 
their administrative resources and make progress reports more timely by 
removing the requirement that they be submitted as formal SIP 
revisions. We are proposing to retain a requirement that states consult 
with FLMs on their progress reports, and that states offer the public 
an opportunity to comment on progress reports before they are 
finalized, which are two of the steps that apply now to progress 
reports that are SIP revisions and which will help ensure ongoing 
accountability for progress reports.
    Finally, the current provisions related to reasonably attributable 
visibility impairment require a recurring process of assessment and 
planning by the states. Experience since the current provisions were 
promulgated suggests that situations involving reasonably attributable 
visibility impairment occur infrequently and therefore that an ``as 
needed'' approach for initiating a state planning obligation would be 
more efficient in the use of resources. The EPA is proposing to replace 
the recurring process of assessment of reasonably attributable 
visibility impairment with an as-needed approach, and given our 
increased understanding of the interstate nature of visibility 
impairment, to expand the applicability for reasonably attributable 
visibility impairment from only states with Class I areas to all 
states. The proposed change to an as-needed approach only applies to 
reasonably attributable visibility impairment; periodic planning for 
purposes of regional haze will continue. This would improve visibility 
protection, if a situation exists or arises in which a source in a 
state without any Class I area causes reasonably attributable 
visibility impairment at a Class I area in another state.
    The EPA also intends to provide states with updated guidance on the 
development of regional haze SIPs, in consultation with the states and 
FLMs, separately from this rulemaking. The guidance will assist states 
as they refocus on reasonable progress analyses for the next regional 
haze implementation period ending in 2028. We expect to invite public 
comment on a draft of this new guidance, and we expect to receive and 
be able to consider those comments before we finalize the Regional Haze 
Rule revisions.

III. What is the background for the EPA's proposed action?

A. Reasonably Attributable Visibility Impairment

    In section 169A of the 1977 Amendments to the CAA, Congress created 
a program for protecting visibility in the nation's national parks, 
wilderness areas and other Class I areas due to their ``great scenic 
importance.'' \4\ 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.''
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    \4\ H.R. Rep. No. 294, 95th Cong. 1st Sess. at 205 (1977).
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    In 1980, the EPA promulgated regulations to address visibility 
impairment in Class I areas, including but not limited to impairment 
that is ``reasonably attributable'' to a single source or small group 
of sources, i.e., ``reasonably attributable visibility impairment.'' 45 
FR 80084 (December 2, 1980). These regulations, codified at 40 CFR 
51.300 through 51.307, represented the first phase in addressing 
visibility impairment from existing sources. They also addressed 
potential visibility and other air quality-related impacts from new and 
modified major sources already subject to permitting requirements for 
purposes of protection of the National Ambient Air Quality Standards 
(NAAQS) and preventing significant deterioration of air quality. The 
EPA explicitly deferred action on regional haze (visibility-impairing 
pollution that is caused by the emission of air pollutants from 
numerous sources located over a wide geographic area) until some future 
date when improvement in monitoring techniques provided more data on 
source-specific levels of visibility impairment, regional scale models 
became refined, and our scientific knowledge about the relationships 
between emitted air pollutants and visibility impairment improved.
    It is important to note that not all states were subject to the 
1980 reasonably attributable visibility impairment requirements. Under 
the 1980 rules, the 35 states and one territory (Virgin Islands) 
containing Class I areas were required to submit SIPs addressing 
reasonably attributable visibility impairment. The 1980 rules required 
states to (1) develop, adopt, implement and evaluate long-term 
strategies for making reasonable progress toward remedying existing and 
preventing future impairment in the mandatory Class I areas through 
their SIP revisions; (2) adopt certain measures to assess potential 
visibility impacts due to new or modified major stationary sources, 
including measures to notify FLMs of proposed new source permit 
applications, and to consider visibility analyses conducted by FLMs in 
their new source permitting decisions; (3) conduct visibility 
monitoring in mandatory Class I areas, and (4) revise their SIPs at 3-
year intervals to assure reasonable progress toward the national 
visibility goal. In addition, the 1980 regulations provide that an FLM 
may certify to a state at any time that visibility impairment at a 
Class I area is reasonably attributable to a single source or small 
group of sources. Following such a certification by an FLM, a state is 
required to address the requirements for best available retrofit 
technology (BART) for BART-eligible sources considered to be 
contributing to reasonably attributable visibility impairment. Also, 
the appropriate control of any source certified by an FLM, whether 
BART-eligible or not, would be specifically addressed in the long-term 
strategy for making reasonable progress toward the national goal of 
natural visibility conditions. See existing Sec.  51.302(c)(2)(i).
    In practice, the 1980 rules resulted in few SIPs being submitted by 
states and approved by the EPA, requiring the EPA to develop and apply 
FIPs to those states that failed to submit an approvable reasonably 
attributable visibility impairment SIP. 52 FR 45132 (November 24, 
1987). Most of these FIPs contain planning requirements only, i.e., 
most of the FIPs merely commit the EPA to assessing on a 3-year cycle 
whether reasonably attributable visibility impairment is occurring and 
to adopting an appropriate strategy of required emission controls if it 
is.
    We are proposing extensive changes to the existing provisions 
regarding reasonably attributable visibility impairment to improve 
coordination with the regional haze program

[[Page 26946]]

requirements and enhance the potential for environmental protection, as 
described in the ``Proposed Rule Changes'' section of this document 
(Section IV.G).

B. Regional Haze

    Regional haze is visibility impairment that is produced by a 
multitude of sources and activities that are located across a broad 
geographic area and emit PM10, PM2.5 (e.g., 
sulfates, nitrates, organic carbon, elemental carbon and soil dust) and 
their precursors (e.g., SO2, NOX and, in some 
cases, ammonia and volatile organic compounds). Fine particle 
precursors react in the atmosphere to form PM2.5, which 
impairs visibility by scattering and absorbing light. This light 
scattering reduces the clarity, color and visible distance that one can 
see. Particulate matter can also cause serious health effects in humans 
(including premature death, heart attacks, irregular heartbeat, 
aggravated asthma, decreased lung function and increased respiratory 
symptoms) and contribute to environmental effects such as acid 
deposition and eutrophication.
    Data from the existing visibility monitoring network, the 
``Interagency Monitoring of Protected Visual Environments'' (IMPROVE) 
monitoring network, show that at the time the Regional Haze Rule was 
finalized in 1999, visibility impairment caused by air pollution 
occurred virtually all the time at most national park and wilderness 
areas. The average visual range \5\ in many Class I areas in the 
western U.S. was 62-93 miles, but in some Class I areas, these visual 
ranges may have been impacted by natural wildfire and dust episodes in 
addition to anthropogenic impacts. In most of the eastern Class I areas 
of the U.S., the average visual range was less than 19 miles. 64 FR 
35715 (July 1, 1999).
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    \5\ Visual range is the greatest distance, in kilometers or 
miles, at which a dark object can be discerned against the sky by a 
typical observer. Visual range is inversely proportional to light 
extinction (bext) by particles and gases and is 
calculated as: Visual Range = 3.91/bext (Bennett, M.G., 
The physical conditions controlling visibility through the 
atmosphere; Quarterly Journal of the Royal Meteorological Society, 
1930, 56, 1-29). Light extinction has units of inverse distance 
(i.e., Mm-1 or inverse Megameters [mega = 10\6\]).
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    Based on visibility data through 2014, considerable visibility 
improvements (4 to 7 deciviews) \6\ have been made in eastern Class I 
areas on the 20 percent haziest days. Some western Class I areas have 
also experienced visibility improvements on the 20 percent haziest days 
(1 to 4 deciviews). However, in some areas, such as Sawtooth Wilderness 
area in Idaho, improvements from reduced emissions from man-made 
sources have been overwhelmed by impacts from wildfire and/or dust 
events. There are also some western areas where visibility has changed 
only by a slight amount.
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    \6\ The deciview haze index (discussed in more detail in Section 
III.B.3 of this document) is logarithmically related to light 
extinction and is used by the regional haze program because it 
describes uniform differences in visibility across a range of 
visibility conditions.
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1. Requirements of the 1990 CAA Amendments and the EPA's Regional Haze 
Rule
    Congress added section 169B to the CAA in 1990 to address regional 
haze issues. Among other things, this section included provisions for 
the EPA to conduct visibility research on regional regulatory tools 
with the National Park Service and other federal agencies, and to 
provide periodic reports to Congress on visibility improvements due to 
implementation of other air pollution protection programs. Section 169B 
also generally allowed the Administrator to establish visibility 
transport commissions and specifically required the Administrator to 
establish a commission for the Grand Canyon area. The EPA promulgated a 
rule to address regional haze in 1999. 64 FR 35714 (July 1, 1999). The 
1999 Regional Haze Rule established a more comprehensive visibility 
protection program for Class I areas. The requirements for regional 
haze are found at 40 CFR 51.308 and 51.309.
    The requirement to submit a regional haze SIP applies to all 50 
states, the District of Columbia and the Virgin Islands.\7\ Congress 
subsequently amended the deadlines for regional haze SIPs, and the EPA 
adopted regulations requiring states to submit the first implementation 
plans addressing regional haze visibility impairment no later than 
December 17, 2007. 70 FR 39104. These initial SIPs were to address 
emissions from certain large stationary sources and other requirements, 
which we discuss in greater detail later. Few states submitted a 
regional haze SIP by the December 17, 2007, deadline, and on January 
15, 2009, the EPA found that 37 states, the District of Columbia and 
the Virgin Islands had failed to submit SIPs addressing the regional 
haze requirements. 74 FR 2392. These findings triggered a requirement 
for the EPA to promulgate FIPs within 2 years unless a state submitted 
a SIP and the EPA approved that SIP within the 2-year period. CAA 
section 110(c). Most states eventually submitted SIPs.\8\
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    \7\ This requirement does not apply to other U.S. territories 
because they do not have mandatory Class I Federal areas and are too 
distant from any such areas to affect them.
    \8\ All states and territories, with the exception of Hawaii, 
Montana and the Virgin Islands, submitted initial regional haze 
SIPs.
---------------------------------------------------------------------------

    Further, 40 CFR 51.308(f) currently requires states to submit 
periodic comprehensive revisions of implementation plans (referred to 
in this document as periodic comprehensive SIP revisions) addressing 
regional haze visibility impairment by no later than July 31, 2018, and 
every 10 years thereafter. These periodic comprehensive SIP revisions 
must address a number of elements, including current visibility 
conditions and actual progress made toward natural conditions during 
the previous implementation period; a reassessment of the effectiveness 
of the long-term strategy in achieving the reasonable progress goals 
over the prior implementation period; and affirmation of or revision to 
the reasonable progress goals. Further information on these periodic 
comprehensive SIP revisions can be found in section III.B.3 of this 
document. In addition, 40 CFR 51.308(g) requires each state to submit 
progress reports, in the form of SIP revisions, every 5 years after the 
date of the state's initial SIP submission. The progress reports are 
required to evaluate the progress made towards the reasonable progress 
goals for mandatory Class I areas located within the state, as well as 
those mandatory Class I areas located outside the state that may be 
affected by emissions from within the state. Further information on 
progress reports can be found in Section III.B.4 of this document.
    The 1999 Regional Haze Rule sought to improve efficiency and 
transparency by requiring states to coordinate planning under the 1980 
reasonably attributable visibility impairment provisions with planning 
under the provisions added by the 1999 Regional Haze Rule. The states 
were directed to submit reasonably attributable visibility impairment 
SIPs every 10 years rather than every 3 years, and to do so as part of 
the newly required regional haze SIPs. Many, but not all, states 
submitted initial regional haze SIPs that committed to this coordinated 
planning process. Coordination of reasonably attributable visibility 
impairment and regional haze planning is described in more detail 
later.
2. Roles of Agencies in Addressing Regional Haze
    Successful implementation of the regional haze program requires 
long-

[[Page 26947]]

term regional coordination among states, tribal governments and various 
federal agencies. As noted earlier, pollution affecting the air quality 
in Class I areas can be transported over long distances, even hundreds 
of miles. Therefore, to effectively address the problem of visibility 
impairment in Class I areas, states need to develop strategies in 
coordination with one another, taking into account the effect of 
emissions from one jurisdiction on the air quality in another.
    Because the pollutants that lead to regional haze can originate 
from sources located across broad geographic areas, and because these 
sources may be numerous and emit amounts of pollutants that, even 
though small, contribute to the collective whole, the EPA has 
encouraged states to address visibility impairment from a regional 
perspective. Five regional planning organizations (RPOs) were formed 
after the promulgation of the Regional Haze Rule in 1999 to address 
regional haze and related issues. The RPOs first evaluated technical 
information to better understand how their states and tribes impact 
Class I areas across the country, and then supported the development 
(by states) of regional strategies to reduce emissions of pollutants 
that lead to regional haze.
3. Requirements for Regional Haze SIPs
    The Regional Haze Rule required the implementation plans due in 
2007, which covered what we refer to as the first implementation 
period, to give specific attention to certain stationary sources that 
were in existence on August 7, 1977, but were not in operation before 
August 7, 1962, by requiring these sources, where appropriate, to 
install BART controls for the purpose of eliminating or reducing 
visibility impairment.
    BART Requirement. Section 169A of the CAA directs states 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 to revise their SIPs to include such measures as 
may be necessary to make reasonable progress towards the natural 
visibility goal, including a requirement that certain categories of 
existing major stationary sources \9\ procure, install and operate 
BART. Under the Regional Haze Rule, the EPA directed states to conduct 
BART determinations for any ``BART-eligible'' sources \10\ that may be 
anticipated to cause or contribute to any visibility impairment in a 
Class I area. The EPA published the Guidelines for BART Determinations 
Under the Regional Haze Rule at appendix Y to 40 CFR part 51 
(hereinafter referred to as the ``BART Guidelines'') to assist states 
in determining which of their sources should be subject to the BART 
requirements and in determining appropriate emission limits for each 
applicable source. 70 FR 39104 (July 6, 2005). The Regional Haze Rule 
also gives states the flexibility to adopt an emissions trading program 
or other alternative program in lieu of source-specific BART as long as 
the alternative provides greater reasonable progress towards improving 
visibility than BART and meets certain other requirements set out in 40 
CFR 51.308(e)(2).
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    \9\ The set of ``major stationary sources'' potentially subject-
to-BART is listed in CAA section 169A(g)(7).
    \10\ 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.
---------------------------------------------------------------------------

    States undertook the BART determination process during the first 
implementation period. The BART requirement was a one-time requirement, 
but BART-eligible sources may need to be re-assessed for additional 
controls in future implementation periods under the CAA's reasonable 
progress provisions. Specifically, we anticipate that BART-eligible 
sources that installed minor controls (or no controls at all) will need 
to be reassessed. States should treat BART-eligible sources the same as 
other reasonable progress sources going forward. Consequently, we are 
not proposing any changes to the BART provisions in this rulemaking.
    Visibility Metric. The Regional Haze Rule established a standard, 
conventional approach to quantifying visibility conditions and tracking 
how they change over time. The Regional Haze Rule established the 24-
hour deciview haze index as the principal metric or unit for expressing 
visibility on any particular day. See 70 FR 39104, 39118. The deciview 
haze index is calculated from light extinction values and expresses 
uniform changes in the degree of haze in terms of common increments 
across the entire range of visibility conditions, from pristine to 
extremely hazy. Deciview values are calculated by using air quality 
measurements to estimate light extinction, most recently using the 
revised IMPROVE algorithm, and then transforming the value of light 
extinction using a logarithmic function.\11\ The deciview is a more 
useful measure for comparing days and tracking progress in improving 
visibility than light extinction itself because each deciview change is 
an equal incremental change in visibility typically perceived by a 
human observer. Most people can detect a change in visibility of one 
deciview. The preamble to the 1999 Regional Haze Rule provides 
additional details about the deciview haze index. We are proposing 
minor editorial changes to definitions related to the deciview index to 
ensure more consistent terminology across sections of the Regional Haze 
Rule.
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    \11\ Pitchford, M.; Malm, W.; Schichtel, B.; Kumar, N.; 
Lowenthal, D.; Hand, J. Revised algorithm for estimating light 
extinction from IMPROVE particle speciation data; J. Air & Waste 
Manage. Assoc. 2007, 57, 1326-1336; doi: 3155/1047-3289.57.11.1326.
---------------------------------------------------------------------------

    Baseline, Current and Natural Conditions and Tracking Changes in 
Visibility. To track changes in visibility over time at each of the 156 
Class I areas covered by the visibility program (40 CFR 81.401-437), 
and as part of the process for determining reasonable progress, states 
must calculate visibility conditions at each Class I area for a 5-year 
period just preceding each periodic comprehensive SIP revision.\12\ To 
do this, the Regional Haze Rule requires states to determine average 
visibility conditions (in deciviews) for the 20 percent least impaired 
days and the 20 percent most impaired days over the 5-year period at 
each of their Class I areas.
---------------------------------------------------------------------------

    \12\ Under the current version of the Regional Haze Rule, states 
must also periodically review progress in reducing impairment every 
5 years.
---------------------------------------------------------------------------

    States must also develop an estimate of natural visibility 
conditions for the purpose of estimating progress toward the national 
goal. Natural visibility is determined by estimating the natural 
concentrations of pollutants that cause visibility impairment and then 
calculating total light extinction based on those estimates. The EPA 
has provided guidance to states regarding how to calculate baseline, 
natural and current visibility conditions at each Class I area.\13\ 
After the EPA issued this guidance, a number of interested parties 
developed alternative estimates of natural conditions using a more 
refined approach (known as ``NC-II''), which

[[Page 26948]]

were used by most states in their first regional haze SIPs with EPA 
approval.\14\
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    \13\ Guidance for Estimating Natural Visibility Conditions Under 
the Regional Haze Rule, September 2003, EPA-454/B-03-005, available 
at http://www3.epa.gov/ttn/caaa/t1/memoranda/rh_envcurhr_gd.pdf; and 
Guidance for Tracking Progress Under the Regional Haze Rule, 
September 2003, EPA-454/B-03-004, available at http://www3.epa.gov/ttn/oarpg/t1/memoranda/rh_tpurhr_gd.pdf.
    \14\ Regional Haze Rule Natural Level Estimates Using the 
Revised IMPROVE Aerosol Reconstructed Light Extinction Algorithm, 
available at http://vista.cira.colostate.edu/improve/Publications/GrayLit/032_NaturalCondIIpaper/Copeland_etal_NaturalConditionsII_Description.pdf; Revised IMPROVE 
Algorithm for Estimating Light Extinction from Particle Speciation 
Data, available at http://vista.cira.colostate.edu/improve/Publications/GrayLit/019_RevisedIMPROVEeq/RevisedIMPROVEAlgorithm3.doc; and Regional Haze Data Analysis 
Workshop, June 8, 2005, Denver, CO, agenda and documents available 
at http://www.wrapair.org/forums/aamrf/meetings/050608den/index.html.
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    Baseline visibility conditions reflect the degree of visibility 
impairment for the 20 percent least impaired days and 20 percent most 
impaired days for each calendar year from 2000 to 2004. Using 
monitoring data for 2000 through 2004, states are required to calculate 
the average degree of visibility impairment for each Class I area, 
based on the average of annual values over the 5-year period. The 
comparison of initial baseline visibility conditions to natural 
visibility conditions indicates the amount of improvement that would be 
necessary to attain natural visibility. Over time, the comparison of 
current conditions \15\ to the baseline conditions will indicate the 
amount of progress that has been made.
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    \15\ Given the required timing of the first regional haze SIPs 
that were due by December 17, 2007, ``baseline visibility 
conditions'' were also the ``current'' visibility conditions. For 
future SIPs, ``current conditions'' will be updated to the 5-year 
period just preceding the SIP revision.
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    The rule text adopted in 1999 defined ``visibility impairment'' as 
a humanly perceptible change (i.e., difference) in visibility from that 
which would have existed under natural conditions. The rule text 
directed the tracking of visibility impairment on the 20 percent ``most 
impaired days'' and 20 percent ``least impaired days'' in order to 
determine progress towards natural visibility conditions. Section 
51.308(d)(2)(i-iv). In light of the 1999 rule's definition of 
``impairment,'' the term ``impaired'' in the phrases ``most impaired 
days'' and ``least impaired days'' could be taken to connote 
anthropogenic impairment. However, the preamble to the 1999 final rule 
stated that the least and most impaired days were to be selected as the 
monitored days with the lowest and highest actual deciview levels, 
respectively. In 2003, the EPA issued guidance describing in detail the 
steps necessary for selecting and calculating light extinction on the 
``worst'' and ``best'' visibility days, and this guidance also 
indicated that the monitored days with the lowest and highest actual 
deciview levels were to be selected as the least and most impaired 
days.\16\ This approach has worked well in many Class I areas but has 
not in other areas. Specifically, the ``worst'' visibility days in some 
Class I areas can be impacted by natural emissions (e.g., wildland 
wildfires and dust storms). These natural contributions to haze vary in 
magnitude and timing. Anticipating this variability, in the 1999 
Regional Haze Rule the EPA had decided to use 5-year averages of 
visibility data to minimize the impacts of the interannual variability 
in natural events. However, as the IMPROVE monitoring network has 
collected more years of data, it has become obvious that in many Class 
I areas 5-year averages are not sufficient for minimizing these 
impacts. As a result, visibility improvements resulting from decreases 
in anthropogenic emissions can be hidden in this uncontrollable natural 
variability. In addition, because of the logarithmic deciview scale, 
changes in PM concentrations and light extinction due to reductions in 
anthropogenic emissions have little effect on the deciview value on 
days with high PM concentrations and light extinction due to natural 
sources. The use of the days with the highest deciview index values, 
without consideration of the source of the visibility impacts, thus has 
created difficulties when attempting to track visibility improvements 
resulting from controls on anthropogenic sources. States have 
identified this difficulty and asked that the EPA explore options for 
focusing the visibility tracking metric on controllable anthropogenic 
emissions. To help states minimize the impacts of uncontrollable 
emissions on visibility tracking, the EPA is proposing to more 
explicitly (and consistently) address this issue for future 
implementation periods in the ``Proposed Rule Changes'' section of this 
document (Sections IV.C. and IV.D).
---------------------------------------------------------------------------

    \16\ Guidance for Tracking Progress Under the Regional Haze 
Rule, September 2003, http://www3.epa.gov/ttnamti1/files/ambient/visible/tracking.pdf.
---------------------------------------------------------------------------

    Reasonable Progress Goals and Long-Term Strategy. To ensure 
continuing progress towards achieving the natural visibility goal, each 
SIP in the series of periodic comprehensive regional haze SIPs must 
establish two distinct reasonable progress goals (one for the most 
impaired and one for the least impaired days) for every Class I area 
for the following implementation period. See 40 CFR 51.308(d) and (f). 
The Regional Haze Rule does not mandate specific milestones or rates of 
progress, but instead calls for states to establish goals that provide 
for ``reasonable progress'' toward achieving natural visibility 
conditions. In setting reasonable progress goals, states must provide 
for an improvement in visibility for the most impaired days over the 
period of the SIP, and ensure no degradation in visibility for the 
least impaired days over the same period. Id. Consistent with the 
requirement in section 169A(b) of the CAA that states include in their 
regional haze SIPs a 10- to 15-year strategy for making reasonable 
progress, Sec.  51.308(d)(3) of the Regional Haze Rule requires that 
states include their long-term strategy in their regional haze SIPs. 
The reasonable progress goals themselves, however, are not enforceable. 
64 FR 35754.
    In establishing reasonable progress goals, states are required to 
consider the following factors set out in the definition of 
``reasonable progress'' in section 169A of the CAA and incorporated 
into the Regional Haze Rule at 40 CFR 51.308(d)(1)(i)(A): (1) The costs 
of compliance; (2) the time necessary for compliance; (3) the energy 
and non-air quality environmental impacts of compliance; and (4) the 
remaining useful life of any potentially affected sources. States must 
demonstrate in their SIPs how these factors have been considered when 
selecting the reasonable progress goals for the least impaired and most 
impaired days for each applicable Class I area. It is important to 
understand that a state's long-term strategy is inextricably linked to 
the reasonable progress goals because the long-term strategy ``must 
include enforceable emission limitations, compliance schedules, and 
other measures as necessary to achieve the reasonable progress goals 
established by states having mandatory Class I Federal areas.'' 40 CFR 
51.308(d)(3). As intended by the EPA and as understood by all states in 
the first implementation period, the four reasonable progress factors 
are considered by a state in setting the reasonable progress goal by 
virtue of the state having first considered them, and certain other 
factors listed in Sec.  51.308(d)(3) of the Regional Haze Rule, when 
deciding what controls are to be included in the long-term strategy. 
Then, the numerical levels of the reasonable progress goals are the 
predicted visibility outcome of implementing the long-term strategy in 
addition to ongoing pollution control programs stemming from other CAA 
requirements. To ensure consistent understanding about the relationship 
between reasonable progress goals and the long-term strategy, we are 
proposing rule text changes to clarify this

[[Page 26949]]

relationship in the ``Proposed Rule Changes'' section of this document 
(Section IV.A). The proposed rule text is consistent with our long-held 
interpretation of the existing rule text as stated earlier.\17\
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    \17\ The EPA's interpretation of the proper relationship between 
a state's reasonable progress goals and its long-term strategy is 
explained in detail in our proposed action on SIPs from Texas and 
Oklahoma. See section IV.C at 79 FR 74828. This interpretation was 
reaffirmed in our final action on these SIPs. See section II.C of 81 
FR 296 (January 5, 2016).
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    In deciding on the long-term strategy and in setting the reasonable 
progress goals, states must also consider the rate of progress for the 
most impaired days that would be needed to reach natural visibility 
conditions by 2064 and the emission reduction measures that would be 
needed to achieve that rate of progress over the approximately 10-year 
period of the SIP. Uniform progress towards achievement of natural 
conditions by the year 2064 represents a rate of progress that states 
are to use for analytical comparison to the amount of progress they 
expect to achieve on average. The CAA has the goal of reaching natural 
conditions,\18\ but does not have any date for achievement of that 
goal, requiring only that plans demonstrate reasonable progress towards 
it. The Regional Haze Rule reiterates the CAA goal, and provides for 
the use of an analytical framework that compares the rate of progress 
that will be achieved by a SIP (as represented by the reasonable 
progress goals for the end of the implementation period) to the rate of 
progress that if continued would result in natural conditions in 2064 
(i.e., the URP). When a SIP contains a reasonable progress goal for the 
most impaired days that reflects progress that is equal to the URP, the 
reasonable progress goal is said to be ``on the URP line'' or ``on the 
glidepath.'' If a state's reasonable progress goal for the most 
impaired days is not on the glidepath, Sec.  51.308(d)(1)(ii) requires 
the state to demonstrate that it would not be reasonable to adopt a 
reasonable progress goal (and by implication a long-term strategy) that 
would be on the glidepath. The Regional Haze Rule does not establish an 
enforceable requirement that natural conditions be reached in 2064. The 
EPA has approved a number of SIPs for the first implementation period 
that have projected that continued progress at the rate expected to be 
achieved during that first period would not result in natural 
conditions until a date after 2064.
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    \18\ The text of the Regional Haze Rule states the goal of 
achieving ``natural visibility conditions.'' Section 169A(a)(1) of 
the CAA calls for ``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.'' 
The D.C. Circuit has affirmed that the Regional Haze Rule properly 
interprets the visibility goal stated in the CAA as achievement of 
``natural visibility conditions.'' American Corn Growers Ass'n v. 
EPA, 291 F.3d 1, 25-27 (D.C. Cir. 2002).
---------------------------------------------------------------------------

    In setting reasonable progress goals, each state with one or more 
Class I areas must also consult with potentially ``contributing 
states,'' i.e., other nearby states with emission sources that may be 
affecting visibility impairment in the state's Class I areas. In such 
cases, the contributing state must demonstrate that it has included in 
its SIP all measures necessary to obtain its share of the emission 
reductions needed to meet the reasonable progress goals for the Class I 
area. Furthermore, section 169A(g)(1) of the CAA and Sec.  
51.308(d)(1)(i)(A) of the Regional Haze Rule require that states 
determine ``reasonable progress'' by considering the four statutory 
factors. Also, Sec.  51.308(d)(3) requires each state to consider its 
own Class I areas (if it has any) and downwind Class I areas (which may 
be affected by emissions from the state) when it develops its long-term 
strategy. In determining whether a state's long-term strategy and 
reasonable progress goals provide for reasonable progress toward 
natural visibility conditions, the EPA is required to evaluate the 
demonstrations developed by the state. 40 CFR 51.308(d)(1). To ensure 
consistent understanding about the long-term strategy obligations of 
all states, we are proposing rule text changes to clarify these 
obligations in the ``Proposed Rule Changes'' section of this document 
(Section IV.B). The proposed rule text is consistent with our long-held 
interpretation of the existing rule text as stated earlier.
    In accordance with the Regional Haze Rule, states should consider 
all types of anthropogenic sources of visibility impairment in 
developing their long-term strategy, including major and minor 
stationary sources, mobile sources and area sources. At a minimum, 
states must describe how each of the following seven factors are taken 
into account in developing their long-term strategy: (1) Emission 
reductions due to ongoing air pollution control programs, including 
measures to address reasonably attributable visibility impairment; (2) 
measures to mitigate the impacts of construction activities; (3) 
emissions limitations and schedules for compliance to achieve the 
reasonable progress goal; (4) source retirement and replacement 
schedules; (5) smoke management techniques for agricultural and 
forestry management purposes including plans as currently exist within 
the state for these purposes; (6) enforceability of emissions 
limitations and control measures; and (7) the anticipated net effect on 
visibility due to projected changes in point, area and mobile source 
emissions over the period addressed by the long-term strategy. 40 CFR 
51.308(d)(3)(v). We are proposing to update the terminology in the 
fifth of these factors. We are not proposing any changes to the current 
requirements regarding the other six factors.
    As discussed earlier, the current version of the Regional Haze Rule 
requires control strategies to cover an initial implementation period 
extending to the year 2018, with a comprehensive reassessment and 
revision of those strategies, as appropriate, every 10 years 
thereafter. The reasonable progress goals are specific to the end date 
of a given implementation period. New reasonable progress goals for the 
end of the next period are established in the next periodic 
comprehensive SIP revision. We are proposing to extend, to July 31, 
2021, the due date for the SIP revision that under the existing 
Regional Haze Rule is due July 31, 2018. This proposed change is 
discussed in the ``Proposed Rule Changes'' section of this document 
(Section IV.J).
    Coordinating Regional Haze and Reasonably Attributable Visibility 
Impairment. The 1999 Regional Haze Rule fulfilled the EPA's 
responsibility to put in place a national regulatory program that 
addresses both reasonably attributable and regional haze visibility 
impairment. As part of the Regional Haze Rule, the EPA revised 40 CFR 
51.306(c) regarding reasonably attributable visibility impairment 
assessment and planning to require that the reasonably attributable 
visibility impairment plan must continue to provide for a periodic 
review and SIP revision not less frequently than every 3 years until 
the date of submission of the state's first plan addressing regional 
haze visibility impairment, which was due December 17, 2007. On or 
before this date, the state must have revised its plan to provide for 
periodic review and revision of a coordinated long-term strategy for 
addressing reasonably attributable visibility impairment and regional 
haze, and the state must have submitted the first such coordinated 
long-term strategy with its first regional haze SIP. Under the current 
version of the regulations, future coordinated long-term strategies, 
and periodic progress reports evaluating progress towards reasonable 
progress goals, must be submitted consistent with the schedule for SIP 
submission and periodic progress reports set forth in 40 CFR 51.308(f) 
and 51.308(g), respectively. The periodic review of a state's long-

[[Page 26950]]

term strategy must report on both regional haze visibility impairment 
and reasonably attributable visibility impairment and must be submitted 
to the EPA in the form of a periodic comprehensive SIP revision. Under 
our proposed changes to the reasonably attributable visibility 
impairment provisions, described in detail in Section IV.G of this 
document, this coordinated approach to a state's long-term strategies 
for regional haze and reasonably attributable visibility impairment 
would continue, but would apply only when the state is under an 
obligation to respond to a reasonably attributable visibility 
impairment certification.
    Monitoring Strategy and Other Implementation Plan Requirements. 
Section 51.308(d)(4) of the Regional Haze Rule includes the requirement 
for a monitoring strategy for measuring, characterizing and reporting 
of regional haze visibility impairment that is representative of all 
mandatory Class I areas within the state. The strategy must be 
coordinated with the monitoring strategy required in the current 
version of Sec.  51.305 for reasonably attributable visibility 
impairment. Compliance with this requirement may be met through 
``participation'' in the IMPROVE network.\19\ A state's participation 
in the IMPROVE network includes state support for the use of CAA state 
and tribal assistance grants funds to partially support the operation 
of the IMPROVE network as well as its review and use of monitoring data 
from the network. The monitoring strategy was due with the first 
regional haze SIP, and under the current Regional Haze Rule it must be 
reviewed every 5 years as part of the progress reports. The monitoring 
strategy must also provide for additional monitoring sites if the 
IMPROVE network is not sufficient to determine whether reasonable 
progress goals will be met. To date, neither the EPA nor any state has 
concluded that the IMPROVE network is not sufficient in this way. The 
evolution of the IMPROVE network will be guided by a Steering Committee 
that has FLM, EPA and state participation, within the evolving context 
of available resources. It is the EPA's objective that individual 
states will not be required to commit to providing monitoring sites 
beyond those planned to be operated by the IMPROVE program during the 
period covered by a SIP revision. The EPA also believes that if the 
IMPROVE program must discontinue a monitoring site, this would not be a 
basis for an approved regional haze SIP to be found inadequate, but 
rather the state, the federal agencies and the IMPROVE Steering 
Committee should work together to address the Regional Haze Rule 
requirements when the next SIP revision is developed. As described in 
Section IV.F of this document, we are proposing that progress reports 
from individual states no longer be required to review and modify as 
necessary the state's monitoring strategy. We believe the IMPROVE 
Steering Committee structure, the requirement to review the monitoring 
strategy as part of the periodic comprehensive SIP revision, and the 
requirement for a state to consider any recommendations from the EPA or 
a FLM for additional monitoring for purposes of reasonably attributable 
visibility impairment will be sufficient to achieve the objective of 
the current progress report requirement to review the monitoring 
strategy.
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    \19\ While compliance with Sec.  51.308(d)(4) for regional haze 
may be met through participation in the IMPROVE network, additional 
analysis or techniques beyond participation in IMPROVE may be 
required for compliance with Sec.  51.305 for reasonably 
attributable visibility impairment.
---------------------------------------------------------------------------

    Consultation between States and FLMs. The existing Regional Haze 
Rule requires that states consult with FLMs before adopting and 
submitting their SIPs. 40 CFR 51.308(i). States must provide FLMs an 
opportunity for consultation, in person and at least 60 days prior to 
holding any public hearing on the SIP. This consultation must include 
the opportunity for the FLMs to discuss their assessment of impairment 
of visibility in any Class I area and to offer recommendations on the 
development of the reasonable progress goals and on the development and 
implementation of strategies to address visibility impairment. Further, 
a state must include in its SIP a description of how it addressed any 
comments provided by the FLMs. Finally, a SIP must provide procedures 
for continuing consultation between the state and FLMs regarding the 
state's visibility protection program, including development and review 
of SIP revisions, progress reports, and the implementation of other 
programs having the potential to contribute to impairment of visibility 
in Class I areas. We are proposing to require that states also consult 
with FLMs earlier in the development of their SIPs, as described in 
Section IV.I of this document.
4. Requirements for the Regional Haze Progress Reports
    The current version of the Regional Haze Rule includes provisions 
for progress reports to be submitted at 5-year intervals, counting from 
the submission of the first required SIP revision by the particular 
state. The requirements for these reports are included for most states 
in 40 CFR 51.308 (g) and (h). Three western states (New Mexico, Utah 
and Wyoming) exercised an option provided in the Regional Haze Rule to 
meet alternative requirements contained in 40 CFR 51.309 for their 
SIPs. For these three states, the requirements for the content of the 
5-year progress reports are identical to those for the other states, 
but for these states the requirements for the reports are codified in 
40 CFR 51.309(d)(10). This section specifies fixed due dates in 2013 
and 2018 for these progress reports. Regardless, the current Regional 
Haze Rule provides that these three states will revert to the progress 
report requirements in 40 CFR 51.308 after the report currently due in 
2018.
    An explanation of the 5-year progress reports is provided in the 
preamble to the 1999 Regional Haze Rule. 64 FR 35747 (July 1, 1999). 
This 5-year review is intended to provide an interim report on the 
implementation of, and, if necessary, mid-course corrections to, the 
regional haze SIP, which, as noted earlier, is prepared in 10-year 
increments. The progress report provides an opportunity for public 
input on the state's (and the EPA's) assessment of whether the approved 
regional haze SIP is being implemented appropriately and whether 
reasonable visibility progress is being achieved consistent with the 
projected visibility improvement in the SIP.
    Required elements of the progress report include: The status of 
implementation of all measures included in the regional haze SIP; a 
summary of the emissions reductions achieved throughout the state; an 
assessment of current visibility conditions and the change in 
visibility impairment over the past 5 years; an analysis tracking the 
change over the past 5 years in emissions of pollutants contributing to 
visibility impairment from all sources and activities within the state; 
an assessment of any significant changes in anthropogenic emissions 
within or outside the state that have occurred over the past 5 years 
that have limited or impeded progress in reducing pollutant emissions 
and improving visibility; an assessment of whether the current SIP 
elements and strategies are sufficient to enable the state (or other 
states with mandatory Class I areas affected by emissions from the 
state) to meet all established reasonable progress goals; a review of 
the state's visibility monitoring strategy and any modifications to the 
strategy as necessary; and a determination of the adequacy of the 
existing SIP (including

[[Page 26951]]

taking one of four possible actions).\20\ We are proposing a number of 
clarifications and changes to the requirements for the content of 
progress reports, as described in Section IV.F of this document.
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    \20\ 40 CFR 51.308(g). See also General Principles for the 5-
Year Regional Haze Progress Reports for the Initial Regional Haze 
State Implementation Plans (Intended to Assist States and EPA 
Regional Offices in Development and Review of the Progress Reports), 
April 2013, EPA-454/B-03-005, available at https://www.epa.gov/sites/production/files/2016-03/documents/haze_5year_4-10-13.pdf, 
(hereinafter referred to as ``our 2013 Progress Report Guidance'').
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    In accordance with 40 CFR 51.308(g) and 51.309(d)(10), progress 
reports must currently take the form of SIP revisions, so states must 
follow formal administrative procedures (including public review and 
opportunity for a public hearing) before formally submitting the 5-year 
progress report to the EPA. See 40 CFR 51.102, 40 CFR 51.103, and 
Appendix V to Part 51--Criteria for Determining the Completeness of 
Plan Submissions. We are proposing to remove the requirement that 
progress reports be submitted as SIP revisions, as described in Section 
IV.L of this document.
    In addition, as with SIPs, states are required to provide FLMs with 
an opportunity for in-person consultation at least 60 days prior to any 
public hearing on an implementation plan or plan revision, which must 
include an opportunity for FLMs to discuss their assessment of 
impairment of visibility in any mandatory Class I area, and discuss 
their recommendations on the development of reasonable progress goals 
and the development of implementation strategies to address visibility 
impairment. See 40 CFR 51.308(i)(2) and (3). Procedures must also be 
provided for continuing consultation between the state and FLM 
regarding development and review of progress reports. See 40 CFR 
51.308(i)(4). We are proposing to preserve the existing requirement for 
consultation with FLMs on progress reports.
    The first progress reports are currently due 5 years from the 
initial SIP submittal (with the next progress reports for New Mexico, 
Utah, and Wyoming due in 2018). Most of these deadlines have already 
passed although some are due in 2016 and in 2017. We are proposing a 
set of common due dates for future progress reports from all states, as 
described in Section IV.K of this document.
5. Tribes and Regional Haze
    Tribes have a distinct interest in regional haze due to the effects 
of visibility impairment on tribal lands as well as on other lands of 
high value to tribal members, such as landmarks considered sacred. 
Tribes, therefore, have a strong interest in emission control measures 
that states and the EPA incorporate into SIPs and FIPs with regard to 
regional haze, and also have an interest in the state response to any 
reasonably attributable visibility impairment certification made by an 
FLM.
    The EPA takes seriously our government-to-government relationship 
with tribes.\21\ The agency has a tribal consultation policy that 
covers any plan that the EPA would promulgate that may affect tribal 
interests. This consultation policy applies to situations where a 
potentially affected source is located on tribal land, as well as 
situations where a SIP or FIP concerns a source that is located on 
state land and may affect tribal land or other lands that involve 
tribal interests. In addition, the EPA has and will continue to 
consider any tribal comments on any proposed action on a SIP or FIP.
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    \21\ Like the EPA, the Department of the Interior and the U.S. 
Forest Service in the U.S. Department of Agriculture have strong 
tribal consultation policies. See: http://www.epa.gov/tribal/consultation/index.htm; http://www.fs.fed.us/spf/tribalrelations/authorities.shtml, and https://www.doi.gov/tribes/Tribal-Consultation-Policy.
---------------------------------------------------------------------------

    In the first implementation period for regional haze SIPs, the 
partnerships within the RPOs included strong relationships between the 
states and the tribes, and the EPA encourages states to continue to 
invest in those relationships (including consulting with tribes), 
particularly with respect to tribes located near Class I areas. States 
should continue working directly with tribes on their SIPs and their 
response to any reasonably attributable visibility impairment 
certification made by an FLM. The EPA believes that it is preferable 
for states to address tribal concerns during their planning process 
rather than the EPA addressing such concerns in its subsequent 
rulemaking process. During the development of this rulemaking, the EPA 
was asked by the National Tribal Air Association to adopt a requirement 
that states formally consult with tribes during the development of 
their regional haze SIPs. While we recognize the value of dialog 
between state and tribal representatives, we are not proposing to 
require it. We note that the CAA does not explicitly authorize the EPA 
to impose such a requirement on the states.

C. Air Permitting

    One part of the visibility protection program, 40 CFR 51.307, New 
Source Review, was created in 1980 with the rationale that while most 
new sources that may impair visibility were already subject to review 
under the Prevention of Significant Deterioration (PSD) provisions 
(Part C of Title I of the CAA), additional regulations would ``ensure 
that certain sources exempt from the PSD regulations because of 
geographic criteria will be adequately reviewed for their potential 
impact on visibility in the mandatory Class I Federal area.'' 45 FR 
80084 (December 2, 1980). The EPA explained at proposal that this was 
necessary because the PSD regulations did not call for the review of 
major emitting facilities (or major modifications) located in 
nonattainment areas,\22\ and that it was appropriate to ``clarify 
certain procedural relationships between the FLM and the state in the 
review of new source impacts on visibility in Federal class I areas.'' 
45 FR 34765 (May 22, 1980). The EPA envisioned that state and FLM 
consultation would commence with the state notifying the FLM of a 
potential new source, and that consultation would continue throughout 
the permitting process. We are proposing to revise Sec.  51.307 only as 
needed to maintain consistency with revisions to other sections of 40 
CFR part 50 subpart P.
---------------------------------------------------------------------------

    \22\ In 1978, PSD rules were put in place that required 
permitting agencies to interact with FLMs and for air quality 
related values (AQRVs) to be taken into consideration in the PSD 
permitting process. 43 FR 26380 (June 19, 1978). Those PSD rules did 
not cover sources in nonattainment areas, and while there were EPA 
rules for nonattainment new source review in existence, they did not 
require consideration of Class I areas. In 1979, 40 CFR part 51, 
appendix S established rules for nonattainment permitting, but they 
did not (and still do not) require consideration of visibility or 
FLM notification. (The same is also true of a more recent addition, 
40 CFR 51.165. Where applicable to nonattainment areas, this rule 
does not require Class I reviews. While 40 CFR 51.165(b) requires 
that sources located in attainment areas cannot cause or contribute 
to a NAAQS violation anywhere, this does not cover AQRVs in Class I 
areas.) As a result, in 1980, the EPA added requirements to 40 CFR 
51.307 for notification of FLMs of pending permits for new sources 
in nonattainment areas.
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IV. Proposed Rule Changes

    The changes being proposed by the EPA will continue steady 
environmental progress in the regional haze program while streamlining 
its administrative aspects that do not add to environmental protection. 
The EPA has gained a substantial amount of knowledge through the 
process of approving SIPs for the first regional haze implementation 
period and has learned what aspects of the program work well and what 
aspects should be modified going forward. Feedback

[[Page 26952]]

received from co-regulators during this process has been invaluable in 
developing this proposal, which seeks to reduce administrative burdens 
of the regional haze program without sacrificing environmental 
protection. Indeed, the EPA believes that reducing administrative 
burdens will result in a more effective program in terms of achieving 
the goal of improved visibility.

A. Clarifications To Reflect the EPA's Long-Standing Interpretation of 
the Relationship Between Long-Term Strategies and Reasonable Progress 
Goals

    The EPA is proposing to amend Sec.  51.308(f) of the Regional Haze 
Rule, which contains the requirements for comprehensive periodic 
revisions to regional haze SIPs, by adding new provisions that will 
govern the development of long-term strategies and reasonable progress 
goals in future implementation periods. We are proposing these changes 
to make clear the connections between the existing long-strategy and 
reasonable progress goal requirements. Although the regional haze SIPs 
submitted by the states during the first planning period generally 
demonstrated a clear understanding of the connections between these two 
program elements, recent comments by some owners of industrial sources 
and states have indicated confusion as to the meaning of these 
provisions. The EPA's proposed revisions to Sec.  51.308(f) are 
consistent with the EPA's long-standing interpretation \23\ of the 
existing regulations at Sec.  51.308(d), but are organized in a more 
logical fashion. While the new provisions track the language of the 
existing regulations at Sec.  51.308(d) in many respects, the EPA also 
has proposed changes in certain places to eliminate ambiguities created 
by the existing language and to conform with substantive changes being 
proposed elsewhere in this rulemaking. In this section, we discuss only 
those changes that are intended to provide clarity regarding the 
relationship between long-term strategies and reasonable progress 
goals. Unlike some of the provisions discussed in subsequent sections 
of this preamble, the changes discussed in this section do not create 
new requirements for states.
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    \23\ The EPA's interpretation of the proper relationship between 
a state's reasonable progress goals and its long-term strategy is 
explained in detail in our proposed action on SIPs from Texas and 
Oklahoma. See section IV.C at 79 FR 74828. This interpretation was 
reaffirmed in our final action on these SIPs. See section II.C at 81 
FR 308 (January 5, 2016).
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    Section 51.308(d) of the existing Regional Haze Rule is organized 
into four subsections: (d)(1), concerning the calculation of reasonable 
progress goals; (d)(2), concerning the calculation of baseline and 
natural visibility conditions; (d)(3), concerning the development of 
long-term strategies; and (d)(4), concerning the development of 
monitoring strategies. This organizational structure does not reflect 
the actual sequence of steps in the regional haze planning process. For 
example, Sec.  51.308(d) lists the requirements for reasonable progress 
goals before the requirements for long-term strategies. In practice, 
states must evaluate the four statutory factors to select emission 
control measures for their long-term strategies before they can 
calculate their reasonable progress goals by modeling the visibility 
improvement that will result from the implementation of those controls.
    To address this issue and provide clarity to states and other 
stakeholders, the EPA is proposing to organize the requirements in 
Sec.  51.308(f) in a more logical fashion. First, proposed subsection 
(f)(1) provides the requirements governing the calculation of baseline 
and natural visibility conditions, which are necessary to calculate the 
URP. A state should calculate current visibility conditions, the URP 
and the URP line first. In doing so, the contributions of PM species to 
current anthropogenic light extinction (referred to as the 
anthropogenic light extinction budget) will become evident, which will 
inform the state's thinking as to which sources or source categories 
should be evaluated for potential reasonable progress control measures. 
Second, proposed subsection (f)(2) provides the requirements governing 
the development of long-term strategies. In this step, states must, 
among other things, evaluate sources that impact visibility at one or 
more Class I areas for potential control measures by considering the 
four statutory factors. Third, proposed subsection (f)(3) provides the 
requirements governing the calculation of reasonable progress goals. 
Once a state has established emission limitations and other control 
measures as part of its long-term strategy, the state will have the 
information necessary to model the visibility improvement that will 
result at each Class I area on the 20 percent most impaired days and 20 
percent clearest days after the long-term strategy has been 
implemented. The projected visibility conditions at the end of the 
applicable implementation period constitute the reasonable progress 
goals. States must then compare the goals for the Class I area to the 
URP. If the goal for the 20 percent most impaired days is above the URP 
line, the state must demonstrate that there are no additional control 
measures for sources reasonably anticipated to contribute to visibility 
impairment in the Class I area that are reasonable to include in the 
long-term strategy. Finally, proposed subsection (f)(6) provides the 
requirements governing monitoring strategies, which must be sufficient 
to allow states to assess the adequacy of their long-term strategies 
going forward.
    In addition to these organizational changes, the EPA is proposing 
new language in Sec.  51.308(f)(2) that differs from the existing 
language in Sec.  51.308(d)(3), but is intended to achieve the same 
result. First, the EPA is proposing language in Sec.  51.308(f)(2)(i) 
and (iv) to clarify that all states, not just those with Class I areas, 
must consider the four statutory factors and properly document all 
cost, visibility and other technical analyses when developing their 
long-term strategies. Second, the EPA is proposing language in Sec.  
51.308(f)(2)(ii) that requires states to consider the URP and the 
measures that contributing states are including in their long-term 
strategies when determining whether the state's own long-term strategy 
is sufficient to ensure reasonable progress.\24\ Finally, the EPA is 
proposing language in Sec.  51.308(f)(2)(iii) to clarify the respective 
obligations of ``contributing states'' and ``states affected by 
contributing states,'' during interstate consultation. As is the case 
under the existing rule text, the EPA will evaluate the sufficiency of 
the record developed by each state, the state's conclusions, and any 
disagreements among states to determine whether the state has used 
reasoned decision making in choosing a set of a control measures that 
will achieve reasonable progress at the Class I areas impacted by the 
state's sources. States must document all substantive interstate 
consultations.
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    \24\ The EPA views this as a clarification of the requirement 
that states with sources affecting a given Class I area consult on 
the content of their long-term strategies. Such consultation would 
be pointless if each state were not meant to consider the other 
states' planned emission control measures.
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B. Other Clarifications and Changes to Requirements for Periodic 
Comprehensive Revisions of Implementation Plans

    The following clarifications and changes are also proposed to be 
included in the revised Sec.  51.308(f).

[[Page 26953]]

    The uniform rate of progress line starts at 2000-2004, for every 
implementation period. The current text of Sec.  51.308(d)(1)(i)(B) 
contains a discussion of how states must analyze and determine ``the 
rate of progress needed to attain natural visibility conditions by the 
year 2064.'' While not actually used within the current rule text, the 
term that has been commonly used to describe this rate is the ``uniform 
rate of progress'' or URP. The current text of Sec.  51.308(f) 
indicates that states must evaluate and reassess all elements required 
by Sec.  51.308(d), and hence the URP, in the second and subsequent 
implementation periods. Section 51.308(d) is not perfectly clear about 
whether ``the rate of progress needed to attain natural visibility 
conditions by the year 2064'' is meant to refer to needed progress 
measured from visibility conditions in the baseline period of 2000-
2004, or further needed progress measured from ``current'' visibility 
conditions (i.e., the visibility conditions during a 5-year period 
ending shortly before SIP submission). In other words, the section is 
not perfectly clear as to whether the glidepath or URP line that 
applies to the SIP for the second or a later implementation period 
always starts in the baseline period of 2000-2004, or in the most 
recent 5-year period. It is clear that the glidepath or URP line then 
reaches natural visibility conditions in ``2064,'' but no exact date in 
2064 is specified.
    To ensure consistent understanding, the EPA is proposing rule 
revisions to state explicitly that in every implementation period, the 
glidepath or URP line for each Class I area is drawn starting on 
December 31, 2004, at the value of the 2000-2004 baseline visibility 
conditions for the 20 percent most impaired days, and ending at the 
value of natural visibility conditions on December 31, 2064. In this 
way, it is clear that for a Class I area that has achieved more than 
the URP in the first implementation period, the state can take that 
into account in its URP analysis for the second implementation period. 
Specifying that the 5-year average baseline visibility conditions are 
associated with the date of December 31, 2004 and that natural 
visibility conditions are associated with the date of December 31, 2064 
also clarifies that the period of time between the baseline period and 
natural visibility conditions, which is needed for determining the URP 
(deciviews/year) is 60 years.
    Note that because of updates to the IMPROVE program, some data 
values from 2000-2004 may be revised over time.\25\ Therefore, the 
value of the starting point for the URP (i.e., baseline visibility 
conditions) should be re-calculated for purposes of accuracy of 
analysis in any given periodic comprehensive SIP revision. In addition, 
the value of the baseline visibility conditions must be recalculated to 
be consistent with the approach used for the selection of the most 
impaired days in the SIP revision under preparation (see Section IV.C 
of this document).
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    \25\ IMPROVE data from the 2000-2004 period may be revised after 
initially reported because of more recently revised methods for 
calculating ambient concentrations from measurements made on filters 
and because of revised methods for filling in missing or invalidated 
data. Such revisions are made in order to maintain consistency in 
reported results across the years.
---------------------------------------------------------------------------

    Along with the clarification that the baseline period remains 2000-
2004 for subsequent implementation periods, the EPA also proposes to 
include clarifications on how states treat Class I areas without 
available monitoring data or Class I areas with incomplete monitoring 
data. If Class I areas do not have monitoring data for the baseline 
period, data from representative sites should be used. If baseline 
monitoring data are incomplete, states should use the 5 complete years 
closest to the baseline period (e.g., if a monitor began operating in 
mid-2000, then 2001-2005 would be used as the baseline period for the 
Class I area). The proposed rule text on this issue, appearing in Sec.  
51.308(f)(1)(i), does not appear in the current Sec.  51.308(d) because 
at the time Sec.  51.308(d) was proposed and finalized, it was not 
anticipated that this data incompleteness situation would exist. We are 
proposing to add this provision to remove any uncertainty about how an 
issue of data incompleteness should be addressed in a SIP.
    As part of this clarification and to maintain consistency in the 
reasonable progress goal framework, the proposed language in Sec.  
51.308(f)(3)(i) (and an accompanying definition of ``end of the 
applicable implementation period'' added to Sec.  51.301) would make 
clear that reasonable progress goals are to address the period 
extending to the end of the year of the due date of the next periodic 
comprehensive SIP revision. Also, proposed Sec.  51.308(f)(1)(iv) 
specifies the end day of 2064 as the ending point of the glidepath or 
URP line.
    Visibility conditions on the clearest 20 percent of days must show 
no deterioration from conditions in 2000-2004. The current text of 
Sec.  51.308(d)(1) states that the reasonable progress goals must 
provide for an improvement in visibility for the most impaired days 
over the period of the implementation plan and ensure no degradation in 
visibility for the least impaired days over the same period. This text 
is ambiguous as to whether ``the period of the implementation plan'' 
refers to the entire period since the baseline period of 2000-2004, or 
to the specific implementation period addressed by the periodic SIP 
revision. However, a summary table in the preamble to the 1999 Regional 
Haze Rule indicated that the 2000-2004 period would be used for 
``tracking visibility improvement.'' \26\ To provide further clarity, 
we are proposing new rule text in revised Sec.  51.308(f)(3)(i) to make 
it clear that the baseline for determining whether there is 
deterioration on the 20 percent clearest days is the baseline period of 
2000-2004.
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    \26\ 64 FR 35730 (July 1, 1999).
---------------------------------------------------------------------------

    Analytical Obligation When the Reasonable Progress Goal for the 20 
Percent Most Impaired Days Is Not On or Below the URP Line. The EPA is 
proposing to clarify how the comparison of the reasonable progress goal 
for the 20 percent most impaired days to the rate of visibility 
improvement needed to attain natural conditions by 2064 (i.e., the 
glidepath or URP line) determines the content of the demonstration the 
state must submit to show that its long-term strategy provides for 
reasonable progress. This clarification appears in the proposed Sec.  
51.308(f)(3)(ii).
    The current text of Sec.  51.308(d)(1)(ii) discusses required 
actions of the state containing the Class I area should it set a 
reasonable progress goal that provides for a slower rate of visibility 
improvement than that needed to attain natural conditions by 2064 
(i.e., a reasonable progress goal for the 20 percent most impaired days 
that is above the URP line). This section provides that in this 
situation, the state must demonstrate, based on the four reasonable 
progress factors, that the rate of progress for the implementation plan 
to attain natural conditions by 2064 is not reasonable, and that the 
progress goal adopted by the state is reasonable. To clarify how a 
state must show that being on the URP line is not reasonable in its SIP 
for the second and subsequent regional haze implementation periods, the 
EPA is proposing in Sec.  51.308(f)(3)(ii)(A) that if the reasonable 
progress goal is above the URP line, the state must demonstrate, based 
on the four reasonable progress factors, that there are no additional 
emission reduction measures for anthropogenic sources or groups of 
sources in the state that may be reasonably anticipated to

[[Page 26954]]

contribute to visibility impairment that would be reasonable to include 
in the long-term strategy. States must provide a robust demonstration, 
including documenting the criteria used to determine which sources or 
groups of sources were evaluated and how the four factors were taken 
into consideration in selecting the measures for inclusion in its long-
term strategy.
    In existing sections 51.308(d)(2)(iv) and 51.308(d)(3)(i) and (ii), 
sentences addressing obligations of the state with the Class I area and 
obligations of the contributing state(s) are juxtaposed in such a way 
that it can be confusing for a reader to understand which of the two 
states is being referred each time the word ``state'' appears. The 
proposed Sec.  51.308(f)(2)(iii) more clearly spells out the respective 
consultation responsibilities of states containing Class I areas as 
well as states with sources that may reasonably be anticipated to cause 
or contribute to visibility impairment in those areas.
    To clarify and solidify the obligations of what we are referring to 
as contributing states, Sec.  51.308(f)(3)(ii)(B) is proposed to 
specify that in situations where reasonable progress goals are set 
above the glidepath, a contributing state must make the same 
demonstration with respect to its own long-term strategy that is 
required of the state containing the Class I area, namely that there 
are no other measures needed to provide for reasonable progress. This 
provision will ensure that states perform rigorous analyses, and adopt 
measures necessary for reasonable progress, with respect to Class I 
areas that their sources contribute to, regardless of whether such 
areas are physically located within their borders.
    Emission inventories. The proposed language of Sec.  
51.308(f)(2)(iv) regarding the baseline emissions inventory to use in 
developing the technical basis for the state's long-term strategy would 
reconcile this section with changes that have occurred to 40 CFR part 
51, subpart A, Air Emissions Reporting Requirements, since the Regional 
Haze Rule was originally promulgated in 1999. The proposed changes also 
would provide flexibility in the base inventory year the state chooses 
to use, as the EPA has always intended if there is good reason to use 
another inventory year.
    EPA action on reasonable progress goals. Proposed language in Sec.  
51.308(f)(3)(iv) would make clear that in approving a state's 
reasonable progress goals, the EPA will consider the controls and 
technical demonstration provided by a contributing state with respect 
to its long-term strategy, in addition to those developed by the state 
containing the Class I area with respect to its long-term strategy. 
This section is a clarification of Sec.  51.308(d)(1)(iii), which only 
explicitly mentions the demonstration provided by the state containing 
the Class I area.
    Progress reports. Finally, proposed language in Sec.  51.308(f)(5) 
complements proposed changes regarding progress reports and the 
proposal to eliminate separate progress reports being due 
simultaneously with periodic comprehensive SIP revisions. This language 
would require the periodic comprehensive SIP revision to include 
certain items of information that would have been addressed in the 
progress report, thereby expanding its scope somewhat. While the state 
would no longer need to prepare and submit two separate documents at 
the same time (the periodic comprehensive SIP revision and a progress 
report), the same information would still be covered. Combining 
requirements in this way will avoid the overlap in content that would 
occur with two separate documents.
    Smoke management programs and basic smoke management practices. The 
proposed Sec.  51.308(f)(2)(vi)(E) mirrors the existing Sec.  
51.308(d)(3)(v)(E) with updates to reflect terminology used within the 
air quality and land management communities to clarify and promote a 
common understanding of this provision. We propose to replace the term 
``smoke management techniques'' in Sec.  51.308(d)(3)(v)(E) with 
``basic smoke management practices.'' We propose to replace the term 
``forestry management purposes'' with ``wildland vegetation management 
purposes'' in recognition that not all wildland for which fire and 
smoke are issues is forested. We also propose to replace the phrase 
``plans'' with ``smoke management programs for prescribed fire.'' Like 
Sec.  51.308(d)(3)(v)(E), the proposed Sec.  51.308(f)(2)(vi)(E) would 
require states to consider only currently existing smoke management 
programs (formerly referred to as ``plans''). Section IV.E of this 
document discusses wildland fire-related issues in more detail and 
includes explanations of the terms ``basic smoke management practices'' 
and ``smoke management program.''

C. Changes to Definitions and Terminology Related to How Days Are 
Selected for Tracking Progress

    Section 51.308(d) of the existing Regional Haze Rule requires 
states to determine the visibility conditions (in deciviews) for the 
average of the 20 percent least impaired and 20 percent most impaired 
visibility days over a specified time period at each of their Class I 
areas. Section 51.301 of the Regional Haze Rule defines visibility 
impairment as the humanly perceptible change in visibility from that 
which would have existed under natural conditions. This definition of 
visibility impairment suggests that only visibility impacts from 
anthropogenic sources should be included when considering the degree of 
visibility impairment. However, the preamble to the 1999 final rule 
stated that the least and most impaired days were to be selected as the 
monitored days with the lowest and highest actual deciview levels, 
respectively. 64 FR 35728 (July 1, 1999). The interpretation in the 
preamble was subsequently reflected in the EPA guidance on setting 
reasonable progress goals and tracking progress. In practice, in their 
SIPs for the first implementation period states followed the approach 
described in the 1999 preamble and the subsequent guidance, and the EPA 
approved the SIPs with respect to that aspect. However, as described 
later, experience now indicates that for the most impaired days an 
approach focusing on anthropogenic impairment in particular is more 
appropriate going forward. We are not proposing to change the approach 
of using the 20 percent of days with the best visibility to represent 
good visibility conditions for reasonable progress goal and tracking 
purposes, but we are proposing text changes to accurately describe how 
those days are to be selected. These days would be referred to as the 
20 percent clearest days.
    Natural contributions to the total actual deciview levels vary from 
year to year. In order to minimize interannual variability, the 
Regional Haze Rule uses 5-year averages for determining the baseline 
and current visibility conditions. Also, under the EPA's modeling 
guidance for regional haze SIPs, reasonable progress goals are 
projected starting from the average of visibility conditions in a 5-
year period that is centered around (or at least includes) the year of 
the base emission inventory used in the air quality modeling process. 
Now that many visibility monitoring sites have at least 15 years of 
data, it is clear that in some locations 5-year averages are not long 
enough to dampen the visibility impacts of occasional extreme fire 
years. In their SIPs and SIP revisions for the first implementation 
period, some states explained that the 20 percent most impaired days in 
certain Class I areas can be dominated by uncontrollable visibility 
impacts. Many states, particularly western states, have urged

[[Page 26955]]

the EPA to make rule changes that would allow them to track visibility 
progress in Class I areas using a method that is more closely linked 
with visibility impacts from controllable emissions.
    To help states minimize the impacts of uncontrollable emissions on 
visibility tracking, the EPA proposes to more explicitly (and 
consistently) address this issue for future implementation periods. In 
general, the proposed changes related to the selection of days for 
visibility tracking are intended to accomplish the following for future 
implementation periods: (1) Clarify that ``visibility impairment'' 
means the deviation from natural visibility and therefore is due to 
anthropogenic impacts, (2) revise definitions in Sec.  51.301 to make 
clear that the 20 percent most impaired days should be selected based 
on anthropogenic visibility impairment rather than based on the days 
with highest deciview values due to impacts from all types of sources, 
and (3) continue to use the 20 percent of days with the lowest total 
deciviews (i.e., ``clearest days'') rather than the 20 percent least 
impaired days for purposes of tracking any adverse trend in visibility 
on clear days.
    The definitions in Sec.  51.301 for several terms and phrases 
related to the selection of days for visibility tracking have been 
clarified in the proposed revisions of the rule text. Definitions that 
are proposed to be changed slightly to provide more clear explanations 
of their meanings include the following: Deciview, most impaired days, 
and visibility impairment.
    Additionally, we propose definitions for the following previously 
undefined terms be included in Sec.  51.301: Clearest days, the 
deciview index (the term was deciview haze index in the 1999 Regional 
Haze Rule), natural visibility conditions and visibility. We propose 
the addition of the term clearest days to unambiguously describe the 
days with the lowest actual deciview values, for which there is to be 
no degradation in visibility.\27\ We propose changing the deciview haze 
index to the deciview index to remove the word haze, since the deciview 
index can be used for visibility impairment as well as for the total 
effect of all sources.\28\ Visibility was previously undefined although 
used in the definitions of several other important terms, and so we 
have added a proposed definition to describe that visibility is the 
change in optical clarity when viewing objects at a distance. We also 
propose adding a definition for natural visibility conditions to 
clarify that natural visibility conditions cannot be measured and must 
be inferred or estimated, and to distinguish the visibility conditions 
that occur due to natural conditions from natural conditions themselves 
such as humidity, emissions from natural sources, etc.
---------------------------------------------------------------------------

    \27\ We are not proposing to remove the definition of least 
impaired days because it will still apply to the first 
implementation period (including the SIPs and progress reports 
covering the first implementation period).
    \28\ We note that the very definition of ``regional haze'' 
refers to ``impairment,'' making it confusing to use ``haze'' to 
refer to the actual level or degree of visibility considering the 
effects of both natural and anthropogenic sources. Our proposed 
edits are aimed at avoiding any inconsistent use of the term 
``haze.''
---------------------------------------------------------------------------

    Given the current Regional Haze Rule's definitions of most impaired 
days and visibility impairment, the regulations could be read to direct 
states and the EPA to use the days with the most perceptible 
anthropogenic impairment as the 20 percent most impaired days. The 
proposed changes to these definitions in Sec.  51.301 do not change 
this direction. The EPA solicits comments on a first proposal, fully 
reflected in the proposed rule text, which would require that states 
select the 20 percent most impaired days based on anthropogenic 
impairment, rather than based on the highest deciview values due to all 
sources affecting visibility. If this approach is finalized, states 
would still have the option to also present the visibility data using 
the current approach based on the days with the highest overall 
deciview index values (i.e., the 20 percent haziest days). Including 
this information in the SIP may help communicate to the public the 
magnitude of impacts from natural sources including wildland wildfires 
and dust storms, and thus the utility of the change in approach. Under 
this first proposal, the reasonable progress goals and URP line that 
are calculated using anthropogenic impairment to select the most 
impaired days will be the glidepath that is used to trigger the 
requirement for a state to show that it is not reasonable for the SIP 
to provide for the rate of progress that would be needed to reach 
natural visibility conditions in 2064 (see Section IV.B of this 
document).
    The EPA seeks comment also on a second, alternative proposal under 
which the final rule would allow each state with a Class I area to 
choose between using the revised approach described earlier (using the 
20 percent most anthropogenically impaired days) and using the 20 
percent haziest days (whether dominated by natural or anthropogenic 
impacts) to track visibility as all states with Class I areas did in 
the first regional haze SIPs. (This alternative approach is not laid 
out in proposed rule text revisions, but only minor edits would be 
required to implement it in the final rule.) If the final rule takes 
this approach, states would still have the option to also present the 
visibility data using the other approach.
    In summary, the EPA seeks comment on two approaches for selecting 
the 20 percent ``worst'' days from the IMPROVE monitoring data. In the 
first approach, states would be required to select the 20 percent most 
impaired days, i.e., the days with the most impairment from 
anthropogenic sources. This first approach would be a change from the 
approach states used in the first implementation period. This first 
approach would also mean that all states would use a framework that is 
consistent on this aspect. In the second approach, states would be 
allowed to choose whether to select the 20 percent of days with the 
highest overall haze (i.e., the approach used in the first 
implementation period) or to select the 20 percent of days with the 
most impairment from anthropogenic sources. EPA also solicits comments 
on additional approaches. The EPA will consider comments received on 
these two options or additional options offered by commenters.
    If the 20 percent most anthropogenically impaired days are used to 
estimate natural visibility conditions, current visibility conditions 
and the URP, they must also be used in setting reasonable progress 
goals and in progress reports. Conforming edits are being proposed to 
the provisions related to each of these, for that purpose. If the final 
rule requires the revised approach described earlier in the first 
proposal, it would apply starting with the second and subsequent 
periodic comprehensive SIP revisions and then to progress reports 
submitted after the second SIP revision. There would be no change with 
respect to the EPA action on SIP revisions for the first implementation 
period.
    In order to select the 20 percent most impaired days based on the 
days with the most anthropogenic impairment, natural contributions to 
daily deciview values must be estimated by some method. This in turn 
requires measured concentration values for PM components to be 
allocated to natural versus anthropogenic sources. The EPA is not 
proposing that any particular method for determining natural 
contributions to daily haze and thus the degree of visibility 
impairment for each monitored day be codified in the rule

[[Page 26956]]

text. The EPA plans to issue guidance describing a recommended approach 
along with a process for routinely providing relevant datasets for use 
by states when they develop their SIPs and progress reports. Because no 
particular method would be prescribed by rule, states could develop, 
justify and use another method in their SIPs, if the final rule 
requires (or allows) the 20 percent most impaired days based on 
anthropogenic impairment to be used.

D. Impacts on Visibility From Anthropogenic Sources Outside the U.S.

    The EPA acknowledges that emissions (natural and anthropogenic) 
from other countries (and from marine vessel activity in non-U.S. 
waters) may impact Class I areas, especially those areas near borders 
and coastlines. We have had requests from states with such Class I 
areas that given these emissions are beyond states' control, the states 
should be allowed to account for international impacts when preparing 
SIPs and progress reports. For example, states have requested that they 
be allowed to consider impacts from international emissions when 
comparing their reasonable progress goals to the URP line. This 
comparison matters because (as described in Section IV.C of this 
document) it may trigger an additional analytical requirement by the 
state. Impacts from international emissions can also affect whether a 
progress report will conclude that actual visibility conditions are 
approaching the reasonable progress goals for the end of the 
implementation period. It has been suggested to the EPA that estimated 
impacts from international emissions might be added to the 2064 end 
point of the URP line. It has also been suggested that estimated 
impacts from international emissions be subtracted from baseline and 
current visibility conditions.
    On this issue, we first wish to clarify that it has never been the 
intention of the EPA that states be obligated to in any way compensate 
for haze impacts from anthropogenic international emissions by adopting 
more stringent emission controls on their own sources. We also wish to 
note that impacts from natural sources in other countries should be 
considered part of natural visibility conditions. States have the 
flexibility under the Regional Haze Rule to justify and use values for 
natural visibility conditions that include such effects. We believe the 
proposed changes regarding which days in a year are used for tracking 
progress (see Section IV.C of this document), when supplemented by our 
planned guidance on this topic, will adequately address international 
impacts related to significant wildland wildfires in Canada and Mexico 
and dust storms in Mexico (and perhaps also dust storms in northern 
Africa).
    The EPA has further considered possible approaches regarding the 
impacts from anthropogenic sources in other countries, including border 
countries as well as more distant countries such as China. It is the 
role of the federal government, much more than of the states, to work 
with other countries to make such reasonable progress. The EPA is, in 
fact, actively engaged with other countries to help them reduce their 
anthropogenic emissions, particularly emissions in Mexico from sources 
near the U.S.-Mexico border. See http://www2.epa.gov/border2020.
    We believe that it may be appropriate to allow states to adjust the 
reasonable progress goal framework, including their progress reports, 
to explicitly take into account international impacts from 
anthropogenic sources, but only when and if these impacts can be 
estimated with sufficient accuracy. We do not believe that explicit 
consideration of impacts from anthropogenic sources outside the U.S. 
would actually affect the conclusions that states should make about 
what emission controls for their own sources are needed for reasonable 
progress. Even so, explicit quantification of international impacts, if 
accurate, could improve public understanding and effective 
participation in the development of regional haze SIPs. Also, taking 
international impacts into account in some cases may affect whether a 
state (and contributing states) are subject to the requirement of 
proposed Sec.  51.308(f)(3)(ii) regarding a demonstration that there 
are not additional emission reduction measures needed for reasonable 
progress. However, we are not convinced that such impacts can be 
estimated with sufficient accuracy at this time, in part due to great 
uncertainty about past, present and future emissions from sources in 
most other countries. However, it may be that by the time some future 
periodic comprehensive SIP revisions are to be prepared, for some 
states possibly as early as when they are preparing their second SIP, 
methods and data for estimating international impacts will be 
substantially more robust.
    Therefore, the EPA is requesting comment on a proposed provision 
that would allow states with Class I areas significantly impacted by 
international emissions to make an adjustment to the URP with specific 
approval by the Administrator. The adjustment would consist of adding 
to the value of natural visibility conditions an estimate of 
international impacts, only for the purpose of calculating the URP.\29\ 
We believe that this adjustment should be permitted only if the 
Administrator determines the international impacts from anthropogenic 
sources outside the United States were estimated using scientifically 
valid data and methods. We are proposing specific rule text for this 
purpose in Sec.  51.308(f)(1)(vi). In addition, we are proposing small 
rule text changes in Sec.  51.308(f)(1)(i) and (vi) (compared to their 
counterparts in Sec.  51.308(d)) to remove ``needed to attain natural 
visibility conditions'' from the reference to ``uniform rate of 
progress,'' because when adjusted to reflect international impacts the 
``uniform rate of progress'' would not be the rate of progress that 
would reach true natural visibility conditions. Because the manner in 
which a state with a Class I area calculates the URP may affect other 
states with sources that contribute to visibility impairment at the 
Class I area,\30\ we recommend that a state seeking approval for such 
an adjustment first consult with contributing states. Such an 
adjustment would also be a topic for the required consultation with the 
FLM for the Class I area at issue. We welcome comments on this proposed 
rule text as well as comments in general support or opposition to this 
concept, noting that the EPA may or may not finalize this portion of 
the proposal.
---------------------------------------------------------------------------

    \29\ As another possible approach to accounting for 
international impacts, the analysis of IMPROVE monitoring data to 
develop the estimates of 2000-2004 baseline visibility conditions 
could include steps to remove the influence of emissions from 
anthropogenic sources outside the U.S. The calculation of the URP 
would be based on this adjusted estimate of baseline visibility 
conditions (see ``The uniform rate of progress line starts at 2000-
2004, for every implementation period'' in Section IV.B of this 
document) and the true value of natural visibility conditions. Also, 
for consistency, the values for current visibility conditions and 
for the projected RPG would exclude the influence of international 
emissions. We invite comment on this alternative approach, which we 
may include in the final rule as the only allowed approach or as 
another allowed approach.
    \30\ Contributing states may be affected because under proposed 
Sec.  51.308(f)(3)(iv)(B), a contributing state may have an 
additional analytical requirement if the RPG does not provide for 
the URP at an affected Class I area in another state.
---------------------------------------------------------------------------

E. Impacts on Visibility From Wildland Fires Within the U.S.

    Fires on wildlands within the U.S. can significantly impact 
visibility in some Class I areas on some days and have lesser impacts 
on a greater number of days. Accordingly, we discuss here whether 
measures to reduce emissions from wildland wildfire and wildland

[[Page 26957]]

prescribed fires may be needed for reasonable progress towards natural 
visibility conditions. We also discuss whether smoke from fires might 
cause the projected RPG to be above the URP line, thus triggering the 
additional analytical requirement (discussed in Section IV.B of this 
document) to show that there are no additional measures that are 
necessary for reasonable progress. We are proposing rule language to 
allow the Administrator to approve a state's proposal to adjust the URP 
to avoid subjecting a state to this additional analytical requirement 
due only to the impacts of specific types of wildland fire. This 
section does not address and does not apply to fires of any type on 
lands other than wildland or to burning on wildland that is for 
purposes of commercial logging slash disposal rather than wildland 
ecosystem health and public safety.
    An extensive discussion of the background on wildland fire 
concepts, including actions that the manager of a prescribed fire can 
take to reduce the amount of smoke generated by a prescribed fire and/
or to reduce public exposure to the smoke that is generated (i.e., 
basic smoke management practices), was presented in the recently 
proposed revisions to the Exceptional Events rule (80 FR 72840, 
November 20, 2015) and is not repeated here. We do wish to note, 
however, that the term ``smoke management program'' is not currently 
defined in the Regional Haze Rule. At the time of the 1999 Regional 
Haze Rule, the term was generally used to mean a framework that 
included (i) authorization to burn, (ii) minimizing air pollutant 
emissions, (iii) smoke management components of burn plans, (iv) public 
education and awareness, (v) surveillance and enforcement and (vi) 
program evaluation. We believe this usage of the term is still 
appropriate. By ``authorization to burn,'' we mean that a government 
authority restricts where, when and/or by whom a prescribed fire may be 
conducted. The proposed Sec.  51.308(f)(2)(v)(E) would make a certain 
state obligation depend on whether a ``smoke management program'' 
currently exists within a state. See ``Consideration of control 
measures for wildland prescribed fire'' in this section for further 
discussion of this point.
    We do not consider the term smoke management program for the 
purposes of Sec.  51.308(f)(2)(v)(E) to mean programs that include only 
seasonal restrictions on burning because of fire safety concerns, 
voluntary educational programs designed to raise air quality awareness 
of potential prescribed fire users, voluntary programs in which land 
managers agree to coordinate their prescribed fire activities but are 
free to withdraw from the program at any time or some combination of 
the above. The EPA supports these latter types of programs, but we do 
not believe it is appropriate to have the obligation in Sec.  
51.308(f)(2)(v)(E) triggered by the existence of these types of 
programs.\31\
---------------------------------------------------------------------------

    \31\ We note that the determining factor for the applicability 
of proposed Sec.  51.308(f)(2)(v)(E) would be the existence of a 
program and its elements, not whether the program has been 
incorporated into the SIP as an enforceable measure or described in 
the narrative portion of the SIP.
---------------------------------------------------------------------------

    The recently proposed revisions to the Exceptional Events Rule 
would clarify that in the context of the regulatory programs for the 
protection of the NAAQS, (i) wildland wildfires are natural events and 
prescribed fires are anthropogenic events; (ii) a wildland wildfire is 
not controllable or preventable (in the sense that generally it would 
not be reasonable to expect efforts at prevention of occurrence and/or 
control of emissions to have gone beyond the efforts actually made for 
a given wildfire by responsible land managers and fire safety 
officials); (iii) a prescribed fire is not reasonably controllable (in 
the sense that it would not have been reasonable to do more to control 
its emissions) if it was conducted in accordance with a state-certified 
smoke management plan or if the burn manager has employed appropriate 
basic smoke management practices; and (iv) a prescribed fire is 
presumptively not reasonably preventable (in the sense that it not 
would have been reasonable to not conduct it, because of the multiple 
important benefits that would have been foregone) if a multi-year land 
or resource management plan \32\ for a wildland area has a stated 
objective to establish, restore and/or maintain a sustainable and 
resilient wildland ecosystem and/or to preserve endangered or 
threatened species through a program of prescribed fire and the use of 
prescribed fire in the area has not exceeded the frequency indicated in 
that plan. These proposed revisions to the Regional Haze Rule do not 
include language to these same four effects because the Regional Haze 
Rule does not contain this level of specificity with respect to any 
source type. However, we do believe these same propositions apply in 
the regional haze context, and the remainder of this section is based 
on these propositions. We invite comment on these propositions, and on 
whether it is appropriate to include in the final rule explicit 
language reflecting them.
---------------------------------------------------------------------------

    \32\ These plans could also include State Forest Action Plans, 
fire management plans, prescribed fire on wildland management plans, 
landscape management plans or equivalent public planning documents.
---------------------------------------------------------------------------

Wildland Wildfires

    As natural events, two issues are associated with wildfires on 
wildland. The first is whether and how a state is obligated to consider 
measures which could reduce emissions from these wildfires as part of a 
regional haze program. The second issue is the one identified at the 
start of this section, namely the possible impact of wildland wildfires 
on whether the RPG is above the URP line and thus whether a state is 
subject to the additional analytical requirement described Section IV.B 
of this document.
    Consideration of control measures for wildland wildfires. Because 
wildland wildfires are considered natural events, emissions from 
wildfires are natural emissions that contribute to natural visibility 
conditions. Thus, states are not obligated to consider whether measures 
to reduce emissions from wildfires are necessary for reasonable 
progress towards natural visibility conditions. However, states may 
consider how use of prescribed fire may reduce the frequency, 
geographic scale and intensity of natural wildfires, such that vistas 
in Class I areas will be clearer on more days of the year, to the 
enjoyment of visitors. States may also consider how the use of 
prescribed fire on wildland can benefit ecosystem health, protect 
public health from the air quality impacts of catastrophic wildfires 
and protect against other risks from catastrophic wildfires. Today's 
proposals are intended to give states that have considered these 
factors, and other relevant factors, the flexibility to provide and 
plan for the use of prescribed fire, with basic smoke management 
practices applied, to an extent and in a manner that states believe 
appropriate. The EPA is committed to working with states, tribes, 
federal land managers, other stakeholders and other federal agencies 
concerning the use of prescribed fire, as appropriate, to reduce the 
impact of wildland fire emissions on visibility.
    Possible effect on the comparison of the RPG to the URP line. 
Because wildland wildfires are natural events, emissions from wildland 
wildfires do not contribute to ``visibility impairment'' given that 
this term refers only to reductions in visibility attributable to 
anthropogenic sources. Under the proposed approach of basing RPGs on 
the 20 percent most impaired days, we expect that days with large 
impacts from wildland wildfires will not be included in the set of days 
selected as the 20 percent most

[[Page 26958]]

impaired days in each year.\33\ Thus, we expect that wildland wildfires 
with notable effects on visibility will not be a reason why a projected 
RPG for the 20 percent most impaired days would be above the URP line, 
simply because the URP line will be about visibility on other types of 
days. Thus, we expect that wildland wildfires will not affect whether a 
state becomes subject to the additional analytical requirement to show 
that there are no additional measures that are necessary for reasonable 
progress. Also, we expect that the 20 percent clearest days (selection 
of which is based on visibility as affected by all types of sources) 
will not include any days with notable effects from wildland wildfires. 
Thus, we expect that wildland wildfires will not affect whether a state 
is able to demonstrate that there is no deterioration in visibility on 
the 20 percent clearest days, which is a requirement for SIP approval.
---------------------------------------------------------------------------

    \33\ We intend to recommend an approach to identifying the 20 
percent most impaired days that uses the ambient concentration of 
carbon-containing material to separate total light extinction 
between natural sources, including wildfires, and anthropogenic 
sources. A day strongly affected by wildfire will have high 
concentrations of carbon-containing material and a very large 
fraction of light extinction will be attributed to natural causes, 
thus the day likely will not be one of the 20 percent most impaired 
days.
---------------------------------------------------------------------------

Wildland Prescribed Fires

    As anthropogenic events, two issues are associated with prescribed 
fires on wildland. The first is whether and how a state is obligated to 
consider measures that could reduce emissions from these prescribed 
fires as part of a regional required haze program. The second issue is 
the possible impact of wildland prescribed fires on whether the RPG is 
above the URP line.
    Consideration of control measures for wildland prescribed fire. 
Under existing Sec.  51.308(d)(2)(i) and proposed revised Sec.  
51.308(f)(2)(v), a state is required to identify all anthropogenic 
sources of visibility impairment considered by the state in developing 
its long-term strategy and the criteria used to select the sources for 
which additional emission reduction measures were considered in light 
of the four reasonable progress factors. Existing Sec.  
51.308(d)(3)(v)(E) more specifically requires a state to consider 
``smoke management techniques for agricultural and forestry management 
purposes including plans as currently exist within the State for these 
purposes.'' As explained in Section IV.B of this document, in carrying 
this paragraph forward into the revision of Sec.  51.308(f) that will 
make it free standing, we are proposing to update some of the 
terminology and to require states to consider ``basic smoke management 
practices for prescribed fire used for agricultural and wildland 
vegetation management purposes and smoke management programs as 
currently exist within the state for these purposes.''
    Taken together, we interpret these provisions to mean that every 
state must consider whether wildland prescribed fires contribute to 
impairment at their own Class I areas or Class I areas in other states. 
If they do not contribute to any meaningful degree, the SIP may take 
note of this and thereby satisfy both provisions. If prescribed fires 
in a state contribute meaningfully to impairment at a Class I area, the 
state is required to consider basic smoke management practices for 
prescribed fires in the development of its long-term strategy, 
regardless of whether or not those practices are currently being 
implemented, required by state law or mandated by an EPA-approved SIP. 
The state would be required to consider only smoke management programs 
as currently exist within the state.\34\ We believe that the state 
should in this situation give new consideration to the effectiveness of 
its smoke management programs in protecting air quality while also 
allowing appropriate prescribed fire for ecosystem health and to reduce 
the risk of catastrophic wildfires. The state could also consider the 
implementation of a new smoke management program.
---------------------------------------------------------------------------

    \34\ We interpret ``currently exist'' in both referenced 
sections of the Regional Haze Rule to refer to programs that are 
operational as of the SIP due date, not the date the Regional Haze 
Rule was promulgated.
---------------------------------------------------------------------------

    We would like to make clear that taken together, these two 
provisions do not necessarily require any state to ``select'' wildland 
prescribed fire (under Sec.  51.308(f)(2)(v)) as an anthropogenic 
source of visibility impairment for which it must consider and analyze 
emission reduction measures (such as a smoke management program or 
basic smoke management practices) based on the four reasonable progress 
factors listed in Sec.  51.308(f)(2)(i). Thus, a state is not 
necessarily required to develop cost estimates for smoke management 
programs or basic smoke management practices. However, if a state does 
not ``select'' wildland prescribed fire as a source for four-factor 
analysis, it must explain why it has not. As previously stated, the 
explanation may be as simple as taking note that prescribed fires do 
not make a meaningful contribution to visibility impairment at in-state 
and nearby Class I areas. Where prescribed fires are more important, it 
may be sufficient for the SIP revision to explain the role of properly 
planned and managed wildland prescribed fire as described in this 
section, the state's ongoing smoke management programs, if any, and the 
current and possibly increased future use of basic smoke management 
practices by federal, state, local and private land managers, but not 
to ``select'' wildland prescribed fire as a source category for four-
factor analysis.
    If a state does ``select'' wildland prescribed fire as a source for 
four-factor analysis, the state must conclude this analysis by 
determining whether additional measures to reduce emissions from 
wildland prescribed fire are necessary for reasonable progress. Any 
such measures must be included in the long-term strategy. Because some 
of the basic smoke management practices are difficult to describe with 
the specificity needed to make them practically enforceable, it may not 
be appropriate to conclude that a SIP requirement for the use of each 
practice is necessary for reasonable progress. For example, one basic 
smoke management practice is to monitor the effects on air quality due 
to the smoke plume from a prescribed fire. ``Monitoring'' could include 
ground-based visual observations, aircraft observations, meteorology-
based modeling, fixed or portable air quality monitoring stations, 
hand-held monitors, etc. Because the most appropriate monitoring 
approach is often situation- and resource-specific, mandating a 
specific approach is inadvisable. Therefore, a SIP commitment for a 
state or local agency to include the use of basic smoke management 
practices could be more desirable than a SIP requirement for land 
managers to use each basic smoke management practice.
    Given the benefits of prescribed fires including the reduction they 
can achieve in visibility-obscuring smoke from wildfires that affect 
visitor's experiences even though not intended to be reflected in the 
metrics for tracking progress towards natural visibility conditions, a 
state may determine that reasonable progress does not require 
implementation of a new or revised smoke management program that 
includes an authorization to burn component,\35\ or it may adopt or 
revise such a smoke management program. We recommend that a smoke 
management program be designed so that it does not inappropriately 
restrict prescribed fires with these benefits. If a state determines 
that compliance with a smoke

[[Page 26959]]

management program of a particular design is required for reasonable 
progress, then the state must include the smoke management program in 
the SIP as part of the long-term strategy. We believe that states can 
include sufficiently detailed, enforceable language in their smoke 
management programs to make them practicably enforceable for SIP 
purposes (as may not be the case for all basic smoke management 
practices). One of the distinguishing elements of a smoke management 
program is a provision for periodic program evaluation. We recommend 
that every smoke management program include a plan for this periodic 
assessment by the responsible authorities that provides for input from 
land managers, affected communities and stakeholders. This evaluation 
should include an assessment of whether the program is meeting its 
goals regarding improving ecosystem health and reducing the damaging 
effects of catastrophic wildfires. We are proposing to add to Sec.  
51.308(g) a requirement for the periodic progress report on a state's 
regional haze program to include a summary of the most recent periodic 
assessment of any smoke management program that is part of the long 
term strategy.
---------------------------------------------------------------------------

    \35\ See the prior discussion of an authorization to burn 
component being one of the six distinguishing features of a ``smoke 
management program'' in the context of the Regional Haze Rule.
---------------------------------------------------------------------------

    While the Regional Haze Rule thus does not require regional haze 
SIPs to include measures to limit emissions from prescribed fire, it is 
not our intention to in any way discourage federal, state, local or 
tribal agencies or private land owners from taking situation-
appropriate steps to minimize emissions from prescribed fires on 
wildland, or other types of land. The EPA encourages all land owners 
and managers to apply appropriate basic smoke management practices to 
reduce emissions from prescribed fires. The EPA understands that the 
FLMs apply these measures routinely and will be available to consult 
with other agencies and private parties interested in doing the same.
    Possible effect on the comparison of the RPG to the URP line. 
Prescribed fire on wildlands may contribute to impairment on some of 
the days that are among the 20 percent most impaired days. Therefore, 
the issue of whether prescribed fires might cause the projected RPG to 
be above the URP line is germane.
    Generally, as discussed earlier in this section, we do not expect 
the total acreage subject to prescribed fires on wildlands to decrease 
in the future because prescribed fire is needed for ecosystem health 
and to reduce the risk of catastrophic wildfires.\36\ Thus, the 
occurrence of prescribed fire generally will not be projected to 
decline towards zero by 2064, nor to decline over any one 
implementation period at the proportional rate inherently assumed in 
the URP line. In fact, in many areas there may be reason to adopt 
policies that facilitate, and accordingly to forecast for purposes of 
setting the RPG, more use of prescribed fire and thus higher 
contributions to impairment on the 20 percent most impaired days. At 
this time, we do not know whether or where such a projected trend may 
affect whether the RPG for a Class I area will be above the URP line. 
However, we expect that if this is an issue, western Class I areas 
would be more likely to be affected.
---------------------------------------------------------------------------

    \36\ See the discussion of climate change effects on wildfire 
trends in the preamble to the proposed revisions of the Exceptional 
Events Rule. 80 FR 72866-72871, November 20, 2015.
---------------------------------------------------------------------------

    If the projected RPG for a Class I area is above the URP line due 
only to the anticipated use of wildland prescribed fire needed for 
ecosystem health and to reduce the risk of catastrophic wildfires, we 
do not believe that states should expend valuable analytical and 
decision making resources on additional analysis of measures necessary 
for reasonable progress if basic smoke management practices have been 
applied to prescribed fires and the states have otherwise satisfied the 
terms of the Regional Haze Rule. Therefore, we are requesting comment 
on a proposed provision in Sec.  51.308(f)(1)(vi) that would allow 
states with Class I areas significantly impacted by emissions from 
wildland prescribed fires to make an adjustment to the URP with 
specific approval by the Administrator. The adjustment would consist of 
adding to the value of natural visibility conditions an estimate of 
wildland prescribed fire impacts, only for the purpose of calculating 
the URP and only for prescribed fires that were conducted with the 
objective to establish, restore and/or maintain sustainable and 
resilient wildland ecosystems, to reduce the risk of catastrophic 
wildfires and/or to preserve endangered or threatened species during 
which appropriate basic smoke management practices were applied. We 
would consider a plan for prescribed fire use on federal, state, tribal 
or private lands with this objective that has been reviewed and 
certified by the appropriate fire and/or resource management 
professionals and agreed to and followed by the land owner/manager to 
be sufficient to meet this restriction on the scope of the adjustment 
to the URP.\37\ Other evidence of the objective of a prescribed fire 
would be considered on a case-by-case basis. We believe that this 
adjustment should be permitted only if such prescribed fire impacts 
have been estimated with methods and data approved by the Administrator 
as scientifically valid.\38\
---------------------------------------------------------------------------

    \37\ Examples of these plans include federal land or resource 
management plans, State Forest Action Plans, fire management plans, 
prescribed fire on wildland management plans or landscape management 
plans.
    \38\ The invitation, in the context of international impacts, 
for comment on alternative adjustment approaches also applies to 
this proposal regarding an adjustment to account for prescribed fire 
impacts. Our recommendation for consultation with other states and 
FLMs in the same context also applies to prescribed fire impacts.
---------------------------------------------------------------------------

    We are also proposing changes to fire-related definitions in Sec.  
51.301. One of the proposed changes is to remove the term ``prescribed 
natural fire'' from the definition of ``fire'' because we consider 
prescribed fires to be anthropogenic, although we recognize that some 
prescribed fires are intended to emulate and/or mitigate natural 
wildfires that would otherwise occur at some point in time. In 
addition, we are adding definitions for wildland, wildfire and 
prescribed fire. The proposed definitions are consistent with the 
definitions we recently proposed for inclusion in the Exceptional 
Events Rule.

F. Clarification of and Changes to the Required Content of Progress 
Reports

    The EPA believes that additional amendments to Sec.  51.308(g) are 
appropriate at this time in order to clarify the substance of the 
regional haze progress reports. In its current form, there is ambiguity 
in this section with respect to the period to be used for calculating 
current visibility conditions, as well as ambiguity with respect to 
whether forward-looking, quantitative modeling is required in the 
progress reports to assess whether reasonable progress goals will be 
met. The EPA wishes to clarify both of these and other issues, and so 
proposes to amend Sec.  51.308(g) in the following ways. The EPA seeks 
comment on these proposed amendments as well as alternative approaches.
    Section 51.308(g)(3)(ii) is proposed to be amended by adding a 
number of explanatory sentences to better indicate what ``current 
visibility conditions'' are and how to calculate them. Under the 
current version of the rule, it is not clear what ``current visibility 
conditions'' are, in part because the term is not defined in Sec.  
51.301. Although Sec.  51.308(g)(3) makes reference to 5-year averages 
of

[[Page 26960]]

annual values for most impaired and least impaired days, and Sec.  
51.308(g)(3)(i) requires states to assess current visibility conditions 
for the most impaired and least impaired days, there is no clear 
indication as to which 5-year average the state should and can 
practicably use in a progress report for the current visibility 
conditions calculation. For example, the ``current conditions'' 
terminology does not explicitly allow for the time delay needed for the 
IMPROVE network manager to get quality assured data into its database 
so they are accessible to the states preparing progress reports. 
Practicality requires that ``current conditions'' should mean 
``conditions for the most recent period of available data.'' \39\ There 
is also an issue of whether this availability is to be determined based 
on the start of work on the progress report, the due date for the 
progress report, or the actual submission date of the progress report. 
The proposed text makes clear that the period for calculating current 
visibility conditions is the most recent rolling 5-year period for 
which IMPROVE data are available as of a date 6 months preceding the 
required date of the progress report. Because we are also proposing 
that progress reports no longer be submitted as SIP revisions, meaning 
that there would be a much simpler and expeditious state administrative 
process to submit a progress report once technical work on it is 
completed, we believe that this 6-month period would be sufficient for 
states to incorporate the most recent available data into their 
progress reports.\40\ The EPA invites comment on other specific 
timeframes as the amount of time necessary for states to incorporate 
the most recent available data into their progress reports, including 3 
months, 9 months and 12 months.
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    \39\ In our guidance on the preparation of progress reports, the 
EPA has indicated that for ``current visibility conditions,'' the 
reports should include the 5-year average that includes the most 
recent quality assured public data available at the time the state 
submits its 5-year progress report for public review. See section 
II.C of General Principles for the 5-Year Regional Haze Progress 
Reports for the Initial Regional Haze State Implementation Plans, 
April 2013.
    \40\ Note that we are not proposing this specification of 6 
months for the progress report aspects of a periodic comprehensive 
SIP revision (see Section IV.C of this document), in light of the 
longer time needed for administrative steps between completion of 
technical work and submission to the EPA.
---------------------------------------------------------------------------

    Section 51.308(g)(3)(iii), as currently written, requires a 
progress report to contain the value of the change in visibility 
impairment for the most and least impaired days over the past 5 years. 
This text fails to make clear what the ``past 5 years'' are for 
assessing the change in visibility impairment. Because of data 
reporting delays, the period covered by available monitoring data will 
not line up with the periods defined by the submission dates for 
progress reports. Moreover, it is important to ensure that each year of 
visibility information is included either in a periodic comprehensive 
SIP revision or the progress report that follows it. Therefore, the 
``past 5 years'' text is proposed to be deleted and replaced with text 
indicating the change in visibility impairment is to be assessed over 
the period since the period addressed in the most recent periodic 
comprehensive SIP revision.
    The same change to existing ``past 5 years'' text is proposed to be 
made to the first sentence of Sec.  51.308(g)(4) for the purposes of 
reporting changes in emissions of pollutants contributing to visibility 
impairment, for similar reasons. Like monitoring trend summaries, 
available emissions trend summaries will not line up with the periods 
defined by the submission dates of progress reports. Therefore, the 
proposed language removes the ``past 5 years'' text and replaces it 
with text indicating the change in emissions of pollutants contributing 
to visibility impairment is to be assessed over the period since the 
period addressed in the most recent periodic comprehensive SIP 
revision.
    The final sentence of Sec.  51.308(g)(4) is proposed to be modified 
to revise and clarify the obligation of states regarding emissions 
inventories. The current rule text directs the analysis be based on the 
``most recent updated emissions inventory,'' with emissions estimates 
``projected forward as necessary and appropriate to account for 
emissions changes during the applicable 5-year period.'' States are 
otherwise required by 40 CFR part 51, subpart A (Air Emissions 
Reporting Requirements) to prepare complete emission inventories only 
for every third calendar year (2011, 2014, etc.) and to submit these 
inventories to the EPA's National Emissions Inventory (NEI). (After 
aggregating and quality assuring these submissions, the EPA then 
publicly provides summaries of the inventories that have been 
submitted.) The current text of Sec.  51.308(g)(4) seemingly requires a 
state to ``project'' the most recent of these inventories to the end of 
the ``applicable 5-year period'' whenever that end is not the year of a 
triennial inventory required by subpart A. Emissions projection is not 
a simple or low-resource task even if limited to a projection date that 
is in the recent past, as would be the case here. We do not think the 
informational value of such projections is in balance with the effort 
and time that would be required. At the same time, we believe that 
progress reports should present for each significant source sector the 
most recently available information, which may be newer for some 
sectors than for others. For most sectors, this will be the information 
for the triennial year of the most recent NEI submission. However, the 
EPA operates a data system that provides information on emissions from 
electric generating units (EGUs), which account for a significant 
percentage of visibility impairing pollution in many states, with only 
a few months lag time. This information comes from reports submitted by 
the EGU operators based on continuous emissions monitoring systems. 
Therefore, we are proposing text changes that explain clearly the most 
recent year through which the emissions analysis must be extended, by 
sector. States would be required to include in their progress reports 
emissions with respect to all sources and activities up to the 
triennial year for which information has already been submitted to the 
NEI. With regard to EGUs, states would need to include data up to the 
most recent year for which the EPA has provided a state-level summary 
of such EGU-reported data. Finally, the last sentence of the proposed 
text for this section makes clear that if emission estimation methods 
have changed from one reporting year to the next, states need not 
backcast, i.e., use the newest methods to repeat the estimation of 
emissions in earlier years, in order to create a consistent trend line 
over the whole period. The EPA has never expected states to backcast in 
this context, but some states have expressed concern that other parties 
may interpret the current Regional Haze Rule as requiring such 
backcasting. This final change would remove any uncertainty about the 
sufficiency of a state's progress report.
    Section 51.308(g)(5) involves assessments of any significant 
changes in anthropogenic emissions that have occurred, and is proposed 
to be changed in a similar fashion to other sections, deleting the 
reference to the ``past 5 years'' and instead directing that the period 
to be assessed involves that since the last periodic comprehensive SIP 
revision. Text is also proposed to be added that would require states 
to report whether these changes were anticipated in the most recent 
SIP. Having this explanation within the progress report should not be a 
significant burden on the state and will

[[Page 26961]]

assist the FLMs, the public and the EPA in understanding the 
significance of any change in emissions for the adequacy of the SIP to 
achieve established visibility improvement goals.
    The existing Sec.  51.308(g)(6) is proposed to be renumbered as 
Sec.  51.308(g)(7). Proposed changes to its provisions regarding 
assessment of progress toward meeting reasonable progress goals would 
clarify that the reasonable progress goals to be assessed are those 
established for the period covered by the most recent periodic 
comprehensive SIP revision. This does not change the intended meaning 
of this section, and only clarifies that in a progress report, a state 
is not required to look forward to visibility conditions beyond the end 
of the current implementation period.
    The new Sec.  51.308(g)(6) is proposed to include a provision 
requiring a state whose long-term strategy includes a smoke management 
program for prescribed fires on wildland to include a summary of the 
most recent periodic assessment of the smoke management program 
including conclusions that were reached in the assessment as to whether 
the program is meeting its goals regarding improving ecosystem health 
and reducing the damaging effects of catastrophic wildfires.
    A final proposed change to Sec.  51.308(g) is to remove the 
provisions of the existing Sec.  51.308(g)(7) entirely, relieving the 
state of the need to review its visibility monitoring strategy within 
the context of the progress report. This change was requested by many 
states during our pre-proposal consultations, and is appropriate in our 
view. Because all states currently rely on their participation in the 
IMPROVE monitoring program and expect to continue to do so, continuing 
the requirement for every state to submit a distinct monitoring 
strategy element in each progress report would consume state and EPA 
resources with little or no practical value for visibility protection. 
As needed, the EPA will work with involved states and the IMPROVE 
Steering Committee to address any needed changes in the visibility 
monitoring program.
    It should be noted that minor changes are proposed to Sec.  
51.308(h) regarding actions the state is required to take based on the 
progress report. These changes merely remove the implication that all 
progress reports are to be submitted at 5-year intervals, and improve 
public understanding of the declaration that a state must make when it 
determines that no SIP revisions are required by removing the word 
``negative.'' Minor changes are also proposed to Sec.  51.308(i) in 
order to create a stand-alone requirement that states must consult with 
FLMs regarding progress reports. This stand-alone requirement is needed 
if progress reports are not SIP revisions, because at present the FLM 
consultation requirements are applicable only to SIP revisions.

G. Changes to Reasonably Attributable Visibility Impairment Provisions

    The EPA is proposing extensive changes to 40 CFR 51.300 through 
51.308 in regard to reasonably attributable visibility impairment. As 
discussed in Section III of this document, the reasonably attributable 
visibility impairment provisions were originally promulgated in 1980, 
when technology for evaluating visibility impairment and its causes was 
in its infancy and visual observation of ``plume blight'' was the main 
method of determining whether a source was affecting a mandatory Class 
I area. Since that time, there have been many advances in ambient 
monitoring, emissions quantification, emission control technology and 
meteorological and air quality modeling. These advances have been built 
into the regional haze program, such that state compliance with the 
Regional Haze Rule's requirements will largely ensure that progress is 
made towards the goal of natural visibility conditions. Therefore, it 
is likely that some aspects of the reasonably attributable visibility 
impairment provisions of the visibility regulations have less potential 
benefit than they did when they originally took effect over 3 decades 
ago. In addition, the reasonably attributable visibility impairment 
provisions have received few amendments over the years, including 
during amendments made by the Regional Haze Rule in 1999 where the 
changes to integrate the reasonably attributable visibility impairment 
assessment and mitigation provisions with the new regional haze program 
requirements were limited to putting the two separately designed 
programs on the same recurring schedule. This has left a substantial 
amount of confusing and outdated language within the current visibility 
regulations including seemingly overlapping and redundant requirements, 
particularly between Sec. Sec.  51.302 and 51.306. Also, as noted in 
Section III.A of this document, in actual practice the portion of the 
reasonably attributable visibility impairment provisions mandating 
periodic assessment of reasonably attributable visibility impairment by 
states (or by the EPA in the case of states that do not have an 
approved reasonably attributable visibility impairment SIP) has not 
resulted in any additional emission control requirements being placed 
on emission sources. While there have historically been very few 
certifications of existing reasonably attributable visibility 
impairment by an FLM, in several situations a certification by an FLM 
has ultimately resulted in new controls or changes in source operation.
    The EPA therefore believes it is time to bring clarity to the 
reasonably attributable visibility impairment provisions of the rule 
and enhance the potential for environmental protection. In brief, our 
proposed changes would (1) eliminate recurring requirements on states 
that we believe have no significant benefit for visibility protection; 
\41\ (2) clarify and strengthen the existing provisions under which 
states must address reasonably attributable visibility impairment when 
an FLM certifies that such impairment is occurring in a particular 
Class I area due to a single source or a small number of sources; (3) 
remove existing FIP provisions that require the EPA to periodically 
assess whether reasonably attributable visibility impairment is 
occurring and to respond to FLM certifications; and (4) edit various 
portions of Sec. Sec.  51.300-308 to make them clearer and more 
compatible with each other. The substantive and clarifying changes are 
described in the following discussion in order of section number. The 
EPA seeks comment on each of the following proposed changes, as well as 
suggestions for alternative approaches to modernizing the reasonably 
attributable visibility impairment provisions.
---------------------------------------------------------------------------

    \41\ These changes, when finalized, would mean that those states 
with SIPs that commit them to periodically assess whether reasonably 
attributable visibility impairment is occurring at their Class I 
areas could remove that commitment from their SIPs.
---------------------------------------------------------------------------

    The EPA is proposing to amend Sec.  51.300, Purpose and 
applicability, to expand the reasonably attributable visibility 
impairment requirements to all states and territories, with the 
exceptions of Guam, Puerto Rico, American Samoa and the Northern 
Mariana Islands. These territories have no mandatory Class I areas and 
are sufficiently far from other Class I areas to have no anticipated 
impact on visibility in such areas. Under our proposal, the geographic 
coverage of the reasonably attributable visibility impairment 
provisions and the regional haze provisions would be the same. The EPA 
believes these changes would strengthen the visibility program and are 
appropriate in light of the evolved understanding that pollutants 
emitted

[[Page 26962]]

from one or a small number of sources can affect Class I areas many 
miles away. In other words, emissions occurring in states without Class 
I areas can affect downwind states with Class I areas. This proposed 
change would provide these areas with additional protection from 
reasonably attributable visibility impairment.
    The EPA is proposing to amend Sec.  51.301, Definitions, to change 
the definition of reasonably attributable. The current definition of 
reasonably attributable is ``attributable by visual observation or any 
other technique the State deems appropriate.'' We are proposing to 
modify this definition to read ``attributable by visual observation or 
any other appropriate technique.'' This change would remove the current 
implication that only a state can determine what techniques are 
appropriate, even though the FLMs are charged with certifying 
reasonably attributable visibility impairment. The proposed change 
would make it clear that a state does not have complete discretion to 
determine what techniques are appropriate for attributing visibility 
impairment to specific sources. It is appropriate that the EPA be able 
to review the technique(s) that an FLM has relied upon to determine 
that reasonably attributable visibility impairment is occurring, in 
light of the views and supporting information provided by both the FLM 
and the state. While these views and supporting information, regardless 
of whether provided by the FLM or by the state, will not be presumptive 
in EPA's ultimate determination as to whether any attribution technique 
used is appropriate, the universe of potentially appropriate 
attribution techniques is not limited to only those techniques that may 
have been utilized during past reasonably attributable visibility 
impairment certifications or that have been previously recommended or 
discussed via EPA guidance or actions. Rather, the aforementioned 
advances in ambient monitoring, emissions quantification, emission 
control technology and meteorological and air quality modeling that 
have occurred in the decades since 1980 make clear that modeling is one 
possible technique for determining that reasonably attributable 
visibility impairment is occurring.
    Due to the confusing, and in large part outdated, content of Sec.  
51.302, the EPA is proposing to delete the entire text of this section 
and replace it with new language. The new text clearly describes a 
state's responsibilities upon receiving a FLM certification of 
reasonably attributable visibility impairment.
    The proposed Sec.  51.302(a) involves FLM certification of 
reasonably attributable visibility impairment and reads much like the 
existing Sec.  51.302(c), with the added language that FLMs would 
identify in the certification which single source or small number of 
sources is responsible for the reasonably attributable visibility 
impairment being certified.\42\ Further, the original reasonably 
attributable visibility impairment formulation did not anticipate a 
situation where one or a small number of sources in one state could 
create impairment of visibility in other state(s). Therefore, proposed 
language is included to explain that the FLMs would provide the 
certification to the state in which the source or small number of 
sources is located, which may not necessarily be the state where the 
visibility impairment occurs. The proposed language also addresses the 
possible situation that a ``small number of sources'' may be partially 
in one state and partially in another, such that a certification might 
be addressed to multiple states.
---------------------------------------------------------------------------

    \42\ The existing rule text at Sec.  51.302(c)(1) does not 
explicitly require the FLM to identify a particular source or small 
number of sources as responsible for the reasonably attributable 
impairment, but the EPA and the FLMs understand that such 
identification should be part of a certification. See 45 FR 80086, 
``The Federal Land Manager may provide the State with a list of 
sources suspected of causing or contributing to visibility 
impairment in the mandatory Class I Federal area.'' Under the 
proposed new language of Sec.  51.302(b), if the FLM does not 
identify the source or small number of sources causing the 
impairment, the certification would not create any obligation on the 
state to respond with a SIP revision.
---------------------------------------------------------------------------

    The proposed Sec.  51.302(b) describes the required state action in 
response to any FLM reasonably attributable visibility impairment 
certification, i.e., regardless of the type of source, namely that a 
state shall revise its regional haze implementation plan to include a 
determination, based on the four reasonable progress factors set forth 
in Sec.  51.308(d)(1)(i)(A), of any controls necessary on the certified 
source(s) to make reasonable progress toward natural visibility 
conditions in the affected Class I area. This preserves the current 
state obligation with much the same wording as in the current section, 
including the fact that a certification by an FLM would not create a 
definite state obligation to adopt a new control requirement, but 
rather only to submit a SIP revision that provides for any controls 
necessary for reasonable progress. In some cases, this SIP revision 
could be combined with an already required SIP revision. The EPA would 
review the responding SIP, and would be available to consult with the 
state and the certifying FLM as the state prepares its responding SIP. 
It would be the EPA, not the certifying FLM, that would determine 
whether the responding SIP is adequate and the response reasonable. The 
proposed section further maintains the current requirement that the 
state include emissions limitations and schedules for compliance, and 
adds the requirement that SIPs include monitoring, recordkeeping and 
reporting requirements in order to enforce those emissions limitations.
    The proposed Sec.  51.302(c) addresses those situations where an 
FLM certifies as a reasonably attributable visibility impairment source 
a BART-eligible source where there is at that time no SIP or FIP in 
place setting BART emission limits for that source or addressing BART 
requirements via a better-than-BART alternative program.\43\ In such an 
instance, the proposed rule requires the state to revise its regional 
haze SIP to meet the requirements of Sec.  51.308(e), BART requirements 
for regional haze visibility impairment, and notes that this 
requirement exists in addition to the requirements of Sec.  51.302(b) 
regarding imposition of controls for reasonable progress. The new 
version of Sec.  51.302(c) clarifies two aspects of the current rule to 
match the EPA's past and current interpretations. First, a reasonably 
attributable visibility impairment certification for a BART-eligible 
source prior to the EPA's approval of a state's BART SIP for that 
source does not impose any substantive obligation on a state that is 
over and above the BART obligation imposed by Sec.  51.308. However, 
the state's response to the reasonably attributable visibility 
impairment certification of a BART-eligible source must take into 
account current information. This may require a state to update an 
analysis prepared earlier in support of a BART SIP that has not been 
approved. Second, a reasonably attributable visibility impairment 
certification of a BART-eligible source after the state's BART SIP for 
that source has been approved by the EPA does not trigger a requirement 
for a new BART determination based on the five statutory factors for 
BART. Rather, the state's obligation with respect to that source is the 
same as for a non-BART eligible source, as stated in the paragraph 
immediately earlier. This is

[[Page 26963]]

true regardless of how the state's SIP has addressed the BART 
requirement for the source, whether through source-specific emission 
limits, an alternative better-than-BART analysis, or the special 
provisions of Sec.  51.309, which may have not resulted in any new 
emission limit for the source.
---------------------------------------------------------------------------

    \43\ Although most of the BART requirements have been addressed 
in most states, there remain a handful of states with BART 
obligations. In addition, there is litigation over the BART element 
in some approved SIPs and promulgated FIPs. We expect that this 
situation may exist in one or more states at some time after the 
effective date of the final rule.
---------------------------------------------------------------------------

    Regarding the time schedule for state response to an FLM 
certification of reasonably attributable visibility impairment, we are 
considering a number of possible approaches for the final rule, with 
proposed rule text provided for three alternative approaches referred 
to as options one, two and three.
    The first alternative proposed rule text at, option one, Sec.  
51.302(d) would retain the existing requirement for a state to respond 
to a reasonably attributable visibility impairment certification with a 
SIP revision within 3 years regardless of when the certification is 
made in the cycle of periodic comprehensive SIP revisions.
    The second alternative proposed rule text, option two, at Sec.  
51.302(d) would require the state's responsive SIP revision to be 
submitted on the due date of the next progress report (but not as part 
of the progress report, if the final rule does not require progress 
reports themselves to be submitted as SIP revisions) or the next 
periodic comprehensive SIP revision, whichever is earlier, provided the 
earlier date is at least 2 years after the RAVI certification.
    The third alternative proposed rule text, option three, at Sec.  
51.302(d) provides for different deadlines for the state response to 
the certification depending on when in the cycle of periodic 
comprehensive SIP revisions the reasonably attributable visibility 
impairment certification is made. Table 1 provides specific examples of 
how application of the third alternative approach in the proposed rule 
text would determine due dates for the state response to a 
certification.
     If the certification is made more than 2 years prior to 
the due date for any periodic comprehensive regional haze SIP revision 
required under Sec.  51.308(f) (but, with respect to the SIP due for 
the just-prior period, not so early as to be within the 6-month window 
described next), then a state must respond to the certification in that 
upcoming SIP revision. Failure to respond adequately would prevent full 
approval of that SIP revision. If the certification is made more than 2 
years before the SIP due date, the state would have more than 2 years 
to respond, except as provided in the next bullet.\44\
---------------------------------------------------------------------------

    \44\ Under the third alternative proposed rule text, for a 
certification made between the 2021 and 2028 SIP due dates, the 
state might have up to 6.5 years to respond, assuming the next 
bullet does not apply. For a certification made between the 2028 and 
2038 due dates, the state might have up to 9.5 years to respond.
---------------------------------------------------------------------------

     If the certification is made less than 2 years prior to 
the due date for any periodic comprehensive SIP revision (but no more 
than 6 months subsequent to the submission date of that periodic 
comprehensive regional haze SIP revision or a SIP revision that amends 
a previous submission in a way that affects the emission limits 
applicable to the reasonably attributable visibility impairment-
certified source),\45\ then the state must submit a revision to its 
regional haze SIP within 2 years from the date of certification. The 
EPA believes that in this second timing situation, when the state's 
analytical infrastructure has been recently used to prepare a SIP 
revision and thus would not be in need of much, if any, refreshment, it 
is appropriate to require a responding SIP revision without waiting 
longer than 2 years for the next periodic comprehensive SIP revision. 
In this timing situation, the EPA would act on the state's standard 
regional haze SIP without regard to the not-yet-due obligation for a 
reasonably attributable visibility impairment-response SIP revision.
---------------------------------------------------------------------------

    \45\ If a certification is made not too long after a SIP due 
date, this parenthetical provision contained in the third 
alternative proposed rule text would operate to require the SIP 
revision needed to respond to the reasonably attributable visibility 
impairment certification to be due sooner than the 6.5 or 9.5 year 
extreme noted in the previous footnote.

   Table 1--Example FLM Reasonably Attributable Visibility Impairment
Certification Dates and Corresponding Due Dates for State Response Under
        the Third Alternative Proposed Rule Text (Option Three).
    [All assume submission of a SIP revision by July 31, 2021, unless
                            otherwise noted.]
------------------------------------------------------------------------
                                             Proposed due date for state
         Date of FLM certification                    response
------------------------------------------------------------------------
July 30, 2019.............................  July 31, 2021.
August 1, 2019............................  August 1, 2021.
January 30, 2022..........................  January 30, 2024.
February 1, 2022..........................  July 31, 2028.
April 1, 2022, after late submission of a   April 1, 2024.
 SIP on March 1, 2022.
August 31, 2022, after revised SIP          August 31, 2024.
 submission on July 31, 2021, affecting
 the source identified in the reasonably
 attributable visibility impairment
 certification.
------------------------------------------------------------------------

    The final rule may incorporate any one of these three proposals, or 
may combine features of these proposals.
    It is important to note that regardless how the final rule sets the 
deadline for the state's responsive SIP revision, if the reasonable 
progress goals in the periodic comprehensive regional haze SIP for a 
state with a Class I area (and thus required to have reasonable 
progress goals in its SIP for that area) have been approved prior to 
the approval of its own or a contributing state's separate reasonably 
attributable visibility impairment-response SIP, the state would not be 
required to revisit and revise its reasonable progress goals to take 
into account any additional emission reductions from the certified 
source until the next due date for a periodic comprehensive SIP 
revision.
    Proposed changes to Sec.  51.303, Exemptions from control, are 
minor edits to paragraph (a) designed to

[[Page 26964]]

correctly refer to the new Sec.  51.302(c) as well as to the BART 
provisions in Sec.  51.308(e). These proposed changes do not alter 
which existing facilities may apply to the Administrator for an 
exemption from BART. Rather, the proposed changes simply make the 
language more clear and direct the reader to the appropriate sections 
for reference information.
    Proposed changes to Sec.  51.304, Identification of integral 
vistas, are more extensive. An integral vista is defined in Sec.  
51.301 as a view perceived from within the Class I area of a specific 
landmark or panorama located outside the boundary of the Class I area. 
The current version of Sec.  51.304 was written at a time when FLMs 
were still in the process of identifying integral vistas. We are 
proposing to remove antiquated language in Sec.  51.304 in light of the 
fact that FLMs were required to identify any such integral vistas on or 
before December 31, 1985. The proposed language would explain this fact 
as well as list those few integral vistas that were properly identified 
during the applicable time period. States would continue to be subject 
to the requirement that these integral vistas be listed in their SIPs. 
The EPA notes that the current version of 40 CFR part 51, subpart P is 
not perfectly clear on how the existence of an identified integral 
vista affects obligations on states and sources, but we are not 
proposing any clarification as part of this rulemaking.\46\ We invite 
comment on whether all references to integral vistas should be removed 
from subpart P, and we may do so in the final rule.
---------------------------------------------------------------------------

    \46\ Section 51.301 states that ``visibility in any mandatory 
Class I Federal area includes any integral vista associated with 
that area'' but also that ``adverse impact on visibility'' does not 
include effects on integral vistas. Section 307(b) requires that 
SIPs provide for the review of any new major stationary source or 
major modification that may have an impact on any integral vista of 
a mandatory Class I Federal area. Other references to ``integral 
vista'' are merely definitional or relate to the procedure for 
identifying integral vistas.
---------------------------------------------------------------------------

    Proposed changes to Sec.  51.305, Monitoring for reasonably 
attributable visibility impairment, involve adding language stating 
that the requirement for a state to include in a periodic comprehensive 
SIP revision a monitoring strategy specifically for evaluating 
reasonably attributable visibility impairment in Class I area(s) only 
applies in situations where the Administrator, Regional Administrator 
or FLM has advised the state of a need for it. In concept, special 
monitoring for reasonably attributable visibility impairment purposes 
might be appropriate for a Class I area without an IMPROVE monitoring 
station or when the impairment is from a relatively narrow plume such 
that the existing IMPROVE monitoring site is not affected. The nature 
of the special monitoring might be situation-specific, and might be the 
same as or different than the IMPROVE monitoring protocols. These 
proposed changes would reduce the paperwork that states are required to 
submit to the EPA on a recurring schedule, since under the proposed 
language a state containing one or more Class I areas and participating 
in the IMPROVE monitoring program would be relieved of the need to 
include information in its SIP regarding monitoring to specifically 
assess reasonably attributable visibility impairment absent being 
advised to do so. A strategy for monitoring for regional haze 
visibility impairment under Sec.  51.308(d)(4) is still required and 
any monitoring for reasonably attributable visibility impairment under 
Sec.  51.305 would be in addition to that requirement.
    Section 51.306, on long-term strategy requirements for reasonably 
attributable visibility impairment, is proposed to be completely 
removed and reserved. Like the current version of Sec.  51.302, the 
language of this section is outdated. In this case, the EPA believes it 
makes sense to delete the entire text of this section and instead refer 
to long-term strategy requirements for reasonably attributable 
visibility impairment within the text of Sec.  51.308, specifically in 
Sec.  51.308(f)(2). In this way, long-term strategy requirements for 
reasonably attributable visibility impairment would be retained in 
clearer form, and the visibility program would be more understandable 
to states and the public by listing the long-term strategy requirements 
for both regional haze and reasonably attributable visibility 
impairment in one place. Such a change would also reduce the planning 
burden on states by making clear in Sec.  51.308(f)(2) that a long-term 
strategy for reasonably attributable visibility impairment is not 
required without an FLM having made a reasonably attributable 
visibility impairment certification under Sec.  51.302(a).
    Several proposed changes in Sec.  51.308 were discussed in Sections 
IV.A, B, C, D, E and F of this document. We are also proposing changes 
in Sec.  51.308 related to reasonably attributable visibility 
impairment. The proposed addition of Sec.  51.308(c) (currently a 
reserved section) explains the relationship between regional haze and 
reasonably attributable visibility impairment and the state 
requirements for each, including that a state would not be required to 
address reasonably attributable visibility impairment unless triggered 
to do so by an FLM certification under Sec.  51.302(a), and that a 
state would not be required to re-address its monitoring strategy for 
reasonably attributable visibility impairment unless advised to perform 
monitoring as described in the proposed Sec.  51.305.
    The EPA is also proposing changes to the language of Sec.  
51.308(f)(2) to describe when reasonably attributable visibility 
impairment must be addressed in the long-term strategy required for 
regional haze. Finally, proposed changes to Sec.  51.308(f)(6) 
regarding the monitoring strategy requirements for SIPs would remove 
references to Sec.  51.305 that exist in the corresponding subsection 
in Sec.  51.308(d), namely, subsection (4) (again, regarding monitoring 
for reasonably attributable visibility impairment).
    Proposed changes to Sec.  51.308(e), BART, relate to a state's 
option to enact an emissions trading program or other alternative 
measure in lieu of source-specific BART. Under the proposed approach, 
if a source is already covered for BART by an approved emissions 
trading program or other alternative measure (or the program codified 
in Sec.  51.309), certification of that source by an FLM would not 
trigger a new BART determination. However, certification would still 
trigger the requirement for a reasonable progress analysis. Proposed 
changes to Sec.  51.308(e)(4) are similar in nature and motivated by 
the same concerns.
    Consistent with our proposal to remove the requirement for states 
to periodically assess reasonably attributable visibility impairment, 
we are also proposing to amend many sections of 40 CFR part 52, to 
remove provisions that establish FIPs that require the EPA to 
periodically assess whether reasonably attributable visibility 
impairment exists at Class I areas in certain states and to address it 
if it does, and to respond to any reasonably attributable visibility 
impairment certification that may be directed to a state that does not 
have an approved reasonably attributable visibility impairment SIP. 
These changes include the removal of Sec. Sec.  52.26 and 52.29, which 
now contain the statement of the EPA's obligations, and specific 
provisions for 30 states to establish that Sec. Sec.  52.26 and 52.29 
are applicable to those states.

H. Consistency Revisions Related to Permitting of New and Modified 
Major Sources

    Proposed changes to Sec.  51.307, New Source Review, involve a few 
proposed

[[Page 26965]]

changes to maintain consistency with other sections of the Regional 
Haze Rule and with the CAA. The first change involves Sec.  
51.307(b)(1) concerning integral vistas, for which we are proposing 
deletion of obsolete language regarding the now-expired identification 
period for integral vistas. Instead, the newly proposed addition of a 
listing of integral vistas in Sec.  51.304(b) will be referenced. In 
section Sec.  51.307(b)(2), the deletion of a reference to specific 
sections of the CAA is proposed in order to remove unnecessary 
language, as the EPA believes a reference simply to section 
``107(d)(1)'' is sufficient.

I. Changes to FLM Consultation Requirements

    The EPA believes that state consultation with FLMs is a critical 
part of the creation of quality SIPs. As mentioned earlier, the EPA is 
proposing to extend the FLM consultation requirements of Sec.  
51.308(i)(2) to progress reports that are not SIP revisions. In 
addition, the EPA believes further edits to Sec.  51.308(i)(2) are 
necessary because the current requirement for consultation at least 60 
days prior to a public hearing may not occur sufficiently early in the 
state's planning process to meaningfully inform the state's development 
of the long-term strategy. This proposed rule change would add a 
requirement that such consultation occur early enough to allow the 
state time for full consideration of FLM input, but no fewer than 60 
days prior to a public hearing or other public comment opportunity. A 
consultation opportunity that takes place no less than 120 days prior 
to a public hearing or other public comment opportunity would be deemed 
to have been ``early enough.''
    Finally, the EPA notes that pursuant to the existing provisions of 
Sec.  51.307(a), the SIP for every state must require the new source 
permitting authority to consult with FLMs regarding new source review 
of any new major stationary source or major modification that would be 
constructed in an area that is designated attainment or unclassified 
that may affect visibility in any Class I Federal area. As required by 
the regulations, that consultation must include sharing with the FLMs a 
copy of all information relevant to the permit application for the 
proposed new stationary source or major modification. The regulations 
also specify that this material must be provided within particular time 
frames. Also, under Sec.  51.307(b)(2), a proposed new major source or 
major modification locating in a nonattainment area is subject to 
review if it may have an impact on visibility in any mandatory Class I 
area. Two EPA guidance documents interpret the consultation 
requirement, particularly with regard to evaluating whether a proposed 
new major source or major modification may affect visibility in a Class 
I area and thus consultation is required.\47\ The EPA regional offices 
can provide additional assistance to states in ensuring that their 
permitting programs meet the regulations and that the appropriate 
consultation is being conducted for affected permits. No changes are 
being proposed to these consultation requirements.
---------------------------------------------------------------------------

    \47\ New Source Review Workshop Manual--Prevention of 
Significant Deterioration and Nonattainment Area Permitting (Draft), 
October 1990, available at: https://www.epa.gov/sites/production/files/2015-07/documents/1990wman.pdf; and Appendix A of Timely 
Processing of Prevention of Significant Deterioration (PSD) Permits 
when EPA or a PSD-Delegated Air Agency Issues the Permit, October 
2012, available at: https://www.epa.gov/sites/production/files/2015-07/documents/timely.pdf.
---------------------------------------------------------------------------

J. Extension of Next Regional Haze SIP Deadline From 2018 to 2021

    The EPA is proposing to amend Sec.  51.308(f) to move the 
compliance deadline for the submission of the next periodic 
comprehensive SIP revisions from July 31, 2018, to July 31, 2021. Under 
this proposal, states would retain the option of submitting their SIP 
revisions before July 31, 2021. Regardless of the date on which a state 
chooses to submit its periodic comprehensive SIP revision, the EPA 
would evaluate that SIP using the same criteria. The EPA is proposing 
to leave the end date for the second implementation period at 2028, 
regardless of when SIP revisions are submitted. We are proposing this 
change as a one-time schedule adjustment. Periodic comprehensive SIP 
revisions for the third planning will be due on July 31, 2028, with 
future periodic comprehensive SIP revisions due every 10 years 
thereafter.
    We are proposing this extension of the due date for periodic 
comprehensive SIP revisions to allow states to coordinate regional haze 
planning with other regulatory programs, including but not limited to 
the Mercury and Air Toxics Standards,\48\ the 2010 1-hour 
SO2 NAAQS,\49\ the 2012 annual PM2.5 NAAQS,\50\ 
and the Clean Power Plan.\51\ With this one-time extension, states 
would be able to gather more information on the effects of these 
programs and develop periodic comprehensive SIP revisions that are more 
integrated with state planning for these other programs, an advantage 
that was widely confirmed in our discussions with states. The Regional 
Haze Rule requires states to address the impacts of other regulatory 
programs when developing their regional haze SIPs. A number of other 
regulatory programs will be taking effect in the coming years, which 
presents an excellent opportunity for states to coordinate their 
strategies to address significant sources of emissions. The EPA expects 
this cross-program coordination to lead to better overall policies and 
enhanced environmental protection.
---------------------------------------------------------------------------

    \48\ 77 FR 9304, February 16, 2012.
    \49\ 75 FR 35520, June 22, 2010.
    \50\ 78 FR 3086, January 15, 2013.
    \51\ 80 FR 64,662, October 23, 2015. The compliance deadlines in 
the Clean Power Plan have been stayed by the Supreme Court. Order in 
Pending Case, West Virginia v. EPA, No. 15A773 (Feb. 9, 2016).
---------------------------------------------------------------------------

K. Changes to Scheduling of Regional Haze Progress Reports

    The EPA is proposing to amend the requirements in 40 CFR 51.308(g) 
and (h) regarding the timing of submission of reports evaluating 
progress towards the natural visibility goal. Under the current rule, 
regional haze progress reports are required to be submitted 5 years 
after submission of periodic comprehensive SIP revisions. Because 
states submitted these first SIP revisions on dates spread across about 
a 3-year period, many of the due dates for progress reports currently 
do not fall mid-way between the due dates for periodic comprehensive 
SIP revisions, as the EPA initially envisioned that they would. Looking 
forward, the current Regional Haze Rule would in many cases require a 
progress report shortly before or shortly after a periodic 
comprehensive SIP revision, at which time it could not be expected to 
have much utility as a mid-course review of environmental progress or 
much incremental informational value for the public compared to the 
data contained in that SIP revision.
    Complementing the proposed amendments to 40 CFR 51.308(f) regarding 
the deadlines for submittal of periodic comprehensive revisions, we 
propose to amend 40 CFR 51.308 (g) and (h) such that second and 
subsequent progress reports would be due by January 31, 2025, July 31, 
2033, and every 10 years thereafter, placing one progress report mid-
way between the due dates for periodic comprehensive SIP revisions. The 
EPA believes that this timing provides a good balance between allowing 
the implementation of the most recent SIP revision to have proceeded 
far enough since its adoption for a review to be possible and 
worthwhile and having enough time

[[Page 26966]]

remaining before the next comprehensive SIP revision for state action 
to make changes in its rules or implementation efforts, if necessary, 
separately from the actions in that next SIP.
    Regarding the concept of a progress report also being useful at or 
near the time of submission of a periodic comprehensive SIP revision, 
as the EPA envisioned in the 1999 Regional Haze Rule, we note that 
although they are expressed with somewhat different terminology, in 
practical terms a progress report would provide little additional 
information beyond that required to be addressed in a periodic 
comprehensive SIP revision. The only significant additional information 
required in a progress report but not explicitly required in a periodic 
comprehensive SIP revision is the requirement to report on the trend in 
visibility over the whole period since the baseline period of 2000-
2004. While the EPA believes that a state should be aware of, and share 
with the public, information on the trend in visibility over the whole 
period since the baseline period of 2000-2004, we believe it would be 
inefficient to require the preparation of a separate progress report 
for this purpose. Therefore, we are proposing to limit the requirement 
for separate progress reports to the one due mid-way between periodic 
comprehensive SIP revisions, and to add to the requirement for periodic 
comprehensive SIP revisions a requirement to include this trend 
information. The EPA believes this approach would substantially reduce 
administrative burdens and make progress reports of more informational 
use to the public, with no attendant reduction in environmental 
protection. The EPA solicits comment on this and any alternative 
approaches to progress report scheduling.

L. Changes to the Requirement That Regional Haze Progress Reports Be 
SIP Revisions

    The EPA is proposing to amend 40 CFR 51.308(g) regarding the 
requirements for the form of progress reports. Under the current 
regulations, progress reports must take the form of SIP revisions that 
comply with the procedural requirements of 40 CFR 51.102, 40 CFR 51.103 
and Appendix V to Part 51--Criteria for Determining the Completeness of 
Plan Submissions. The EPA included the requirements for progress 
reports in the Regional Haze Rule primarily with an emphasis toward 
ensuring that the states remain on track during the 10 years between 
periodic comprehensive SIP revisions. By requiring progress reports to 
be in the form of SIP revisions, the 1999 Regional Haze Rule ensured an 
opportunity for public input on the progress reports, while 
specifically pointing out that the EPA ``intends for progress reports 
to involve significantly less effort than a comprehensive SIP 
revision.'' 64 FR 35747 (July 1, 1999). For all SIP revisions, however, 
the state must provide public notice and a public hearing if requested, 
and it must conform to certain administrative procedural requirements 
and provide various administrative material. Also, the submission must 
be made by an official who is authorized by state law to submit a SIP 
revision. As a required SIP revision, a finding by the EPA that a state 
has not submitted a complete progress report by the deadline would 
start a ``clock'' for the EPA to prepare, take public comment on, and 
issue a progress report like the state was required to submit.
    We are proposing that progress reports need not be in the form of 
SIP revisions, but that states must consult with FLMs and obtain public 
comment on their progress reports before submission to the EPA. We are 
also proposing that the SIP revision that would be due in 2021 must 
include a commitment to prepare and submit these progress reports to 
the EPA according to the proposed revised schedule (see previous 
section). These progress reports would be acknowledged and assessed by 
the EPA, but our review of these reports would not result in a formal 
approval or disapproval of them.
    The EPA is proposing these changes because it believes these 
reports are not the kind of state submissions for which the formality 
of a SIP revision, and the accompanying requirement for the EPA to have 
to prepare the report within 2 years of finding that a state has failed 
to do so, are warranted. It is important to note that as part of the 
EPA's review of the report, we will follow up with the state on any 
appropriate next steps. There are also additional remedies, such as 
undertaking a less formal assessment of the results of the 
implementation of the previously submitted SIP, that are available to 
the EPA in the event a state fails to properly submit a progress 
report. These changes have been widely supported by state air agencies 
in our pre-proposal consultations because they would allow more 
efficient use of state resources. This option would relieve states of 
the obligation to follow the procedural requirements of 40 CFR 51.102 
and 51.103. States have expressed concern that these procedural 
requirements are resource-intensive, and increase the burden on states 
by requiring formal procedures be followed when submitting progress 
reports. By avoiding the specific formal steps required for a SIP 
revision, including requirements imposed by state law that may involve 
time-consuming steps beyond those required by the EPA, this proposal 
may also reduce the time between the completion of the technical 
analysis in the progress report and when the final report becomes 
available to the EPA and the public. Thus, progress reports could 
contain fresher information on the environmental progress being made by 
a state. Removing the requirement that progress reports be submitted as 
SIP revisions is consistent with regulatory requirements for similar 
reports from states for progress reporting or planning purposes where 
control requirements are not imposed, such as annual monitoring plans 
required for planning and maintenance of state monitoring networks.\52\
---------------------------------------------------------------------------

    \52\ See 40 CFR 58.10(a)(1) and (2).
---------------------------------------------------------------------------

    The EPA invites comment on whether it should finalize this proposed 
change. Also, the EPA invites comment on changing the progress report 
scheduling as described in the previous section without making any 
change to the requirement that progress reports take the form of SIP 
revisions, and vice versa.
    It is important to note that under this option, states would still 
be required to include the required progress report elements listed in 
40 CFR 51.308(g)(1) through (g)(6). Also, Sec.  51.308(h) would 
continue to require that at the same time the state is required to 
submit a progress report, it must also take one of four listed actions 
concerning whether the SIP is adequate to achieve established goals for 
visibility improvement. Where a state determines that its own SIP is or 
may be inadequate to ensure reasonable progress due to emissions from 
sources within the state, the state will continue to have an obligation 
to revise its SIP to address the plan's deficiencies within 1 year of 
its submission of such a determination.
    Upon receipt of such progress reports, the EPA would review the 
reports. In addition, the EPA intends to create a system of logging 
progress reports as they are received, and making them available to the 
public. In addition to putting the public on notice that a progress 
report was received by the EPA, this system would provide the public an 
opportunity to view the contents of the progress report. Although the 
EPA would not formally approve or disapprove a progress report,

[[Page 26967]]

the EPA would still have discretion to assess the adequacy of the SIP, 
relying in part on the information in the progress report. Under the 
CAA, a discretionary determination that the SIP is inadequate would 
create a non-discretionary duty for the EPA to issue a SIP call 
requiring the state to correct the inadequacy. A failure by the state 
to submit a progress report could be determined by the EPA to 
constitute failure to implement the regional haze SIP, given that we 
are proposing that every regional haze SIP include a commitment to 
submit the required progress reports (see next paragraph).
    We are proposing that the next periodic comprehensive SIP revisions 
(currently due in 2018 but proposed to be due in 2021) would need to 
include a commitment for states to provide progress reports. The 1999 
Regional Haze Rule does not require such a commitment because the 
current requirement for progress reports to be submitted in the form of 
SIP revisions makes such a commitment superfluous. The EPA solicits 
comment on this or alternative approaches to ensuring that states 
continue to provide progress reports.

M. Changes to Requirements Related to the Grand Canyon Visibility 
Transport Commission

    Section 51.309 has limited applicability going forward because its 
provisions apply only to 16 Class I areas covered by the Grand Canyon 
Visibility Transport Commission Report, and only to the first regional 
haze implementation period (i.e., through 2018). Nevertheless, certain 
conforming amendments at this time are appropriate to avoid confusion 
going forward. Section 51.309(d)(4)(v) is proposed to be amended to 
correctly refer to the new Sec.  51.302(b) (in lieu of (e), which no 
longer exists in the proposed section Sec.  51.302) and to delete the 
reference to BART since it does not appear in Sec.  51.302(b). The 
title of Sec.  51.309(c)(10), Periodic implementation plan revisions, 
is proposed to be amended to include ``and progress reports'' at the 
end. This insertion would complement the proposed amendments that will 
no longer require progress reports be considered SIP revisions by 
making clear from the title of the section that it applies to both SIP 
revisions and progress reports. Within Sec.  51.309(c)(10), amendments 
are proposed that would preserve the existing requirement that the 
progress reports due in 2013 were to take the form of SIP revisions, 
but direct the reader to the provisions of Sec.  51.308(g) for 
subsequent progress reports. In similar fashion, Sec.  51.309(c)(10)(i) 
and (ii) would be amended to specifically refer to the 2013 progress 
reports, while Sec.  51.309(c)(10)(iii) would point to Sec.  51.308(g) 
for subsequent progress reports. Section 51.309(c)(10)(iv) is proposed 
to be added to indicate that subsequent progress reports are subject to 
the requirements of Sec.  51.308(h) regarding determinations of 
adequacy of existing SIPs.
    A final change in section 51.309 appears in Sec.  
51.309(g)(2)(iii). This change is purely to correct a typographical 
error and the EPA will therefore not consider comments on this 
subsection.

V. Environmental Justice Considerations

    The EPA believes this action would not have disproportionately high 
and adverse human health, well-being or environmental effects on 
minority, low-income or indigenous populations because it would not 
negatively affect the level of protection provided to human health, 
well-being or the environment under the CAA's visibility protection 
program. When promulgated, these proposed regulations will revise 
procedural and timing aspects of the SIP requirements for visibility 
protection but will not substantively change the requirement that SIPs 
provide for reasonable progress towards the goal of natural visibility 
conditions. These SIP requirements are designed to protect all segments 
of the general population.
    The EPA acknowledges that the proposed delay in submitting SIP 
revisions from 2018 to 2021 might cause delays in when sources must 
comply with any new requirements. However, because neither the CAA nor 
the existing Regional Haze Rule set specific deadlines for when sources 
must comply with any new requirements in a state's next periodic 
comprehensive SIP revision, states have substantial discretion in 
establishing reasonable compliance deadlines for measures in their 
SIPs. Given this, we expect to see a range of compliance deadlines in 
the next round of regional haze SIPs from early in the second 
implementation period to 2028, depending on the types of measures 
adopted, whether or not these proposed rule changes are finalized. 
Thus, the EPA believes the delay in the periodic comprehensive SIP 
revision submission deadline from 2018 to 2021 will not meaningfully 
reduce the overall progress towards better visibility made by the end 
of 2028 and will not meaningfully adversely affect environmental 
protection for all general segments of the population.

VI. Statutory and Executive Order Reviews

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

    This action is a significant regulatory action that was submitted 
to the OMB for review because it raises novel policy issues. Any 
changes made in response to OMB recommendations have been documented in 
the docket.

B. Paperwork Reduction Act (PRA)

    The information collection activities in this proposed rule have 
been submitted for approval to the OMB under the PRA. The ICR document 
that the EPA prepared has been assigned the EPA ICR number 2540.01. OMB 
has previously approved the information collection activities contained 
in the existing regulations and has assigned OMB control number 2060-
0421. You can find a copy of the ICR in the docket for this rule, and 
it is briefly summarized here.
    The EPA is proposing these amendments to requirements for state 
regional haze planning to change the requirements that must be met by 
states in developing regional haze SIPs, periodic comprehensive SIP 
revisions, and progress reports for regional haze. The main intended 
effects of this rulemaking are to provide states with additional time 
to submit regional haze plans for the second implementation period and 
to provide states with an improved schedule and process for progress 
report submission. Further reductions in burden on states include this 
proposal's removal of the requirement for progress reports to be SIP 
revisions, clarifying that states are not required to project emissions 
inventories as part of preparing a progress report, and relieving the 
state of the need to review its visibility monitoring strategy within 
the context of the progress report. With all of these proposed changes 
considered, the overall burden on states would represent a reduction 
compared to what would otherwise occur if the provisions of the current 
rule were to stay in place. Total estimated burden is estimated to be 
reduced from 10,307 hours (per year) to 5,974 hours (per year), and 
total estimated cost is expected to be reduced from $510,498 (per year) 
to $295,876 (per year). All states are required to submit regional haze 
SIPs and progress reports under this rule.
    Respondents/affected entities: All state air agencies.
    Respondent's obligation to respond: Mandatory, in accordance with 
the

[[Page 26968]]

provisions of the 1999 Regional Haze Rule.
    Estimated number of respondents: 52: 50 states, District of 
Columbia and U.S. Virgin Islands.
    Frequency of response: Approximately every 10 years (SIP) and 
approximately every 10 years (progress report).
    Total estimated burden: 5,974 hours (per year). Burden is defined 
at 5 CFR 1320.3(b).
    Total estimated cost: $295,876 (per year), includes $0 annualized 
capital or operation & maintenance costs.
    An agency may not conduct or sponsor, and a person is not required 
to respond to, a collection of information unless it displays a 
currently valid OMB control number. The OMB control numbers for the 
EPA's regulations in 40 CFR are listed in 40 CFR part 9.
    Submit your comments on the agency's need for this information, the 
accuracy of the provided burden estimates and any suggested methods for 
minimizing respondent burden to the EPA using the docket identified at 
the beginning of this rule. You may also send your ICR-related comments 
to OMB's Office of Information and Regulatory Affairs via email to 
oira_submissions@omb.eop.gov, Attention: Desk Officer for the EPA. 
Since OMB is required to make a decision concerning the ICR between 30 
and 60 days after receipt, OMB must receive comments no later than June 
3, 2016. The EPA will respond to any ICR-related comments in the final 
rule.

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. Entities 
potentially affected directly by this proposal include state 
governments, and for the purposes of the RFA, state governments are not 
considered small government. Tribes may choose to follow the provisions 
of the Regional Haze Rule but are not required to do so. Other types of 
small entities are not directly subject to the requirements of this 
rule. The EPA continues to be interested in the potential impacts of 
the proposed rule on small entities and welcomes comments on issues 
related to such impacts.

D. Unfunded Mandates Reform Act (UMRA)

    This action does not contain any unfunded mandate as described in 
UMRA, 2 U.S.C. 1531-1538, and does not significantly or uniquely affect 
small governments. This action imposes no enforceable duty on any 
state, local or tribal governments or the private sector. The CAA 
imposes the obligation for states to submit regional haze SIPs. In this 
rule, the EPA is proposing to revise those requirements in a manner 
that would not increase the obligation of any state, local or tribal 
governments or the private sector. In this rule, the EPA is also 
proposing to extend the reasonably attributable visibility impairment 
certification provisions to some additional states, but these states 
are not small governments and any mandate on the private sector would 
be indirect since this rule does not mandate how an affected state 
should address such a certification. Therefore, this action is not 
subject to the requirements of sections 202, 203 and 205 of the UMRA.

E. Executive Order 13132: Federalism

    This action does not have federalism implications. It will not have 
substantial direct effects on the states, on the relationship between 
the national government and the states, or on the distribution of power 
and responsibilities among the various levels of government. The 
requirement to submit regional haze SIPs is mandated by the CAA. Thus, 
Executive Order 13132 does not apply to these proposed regulations.
    In the spirit of Executive Order 13132 and consistent with the EPA 
policy to promote communications between the EPA and state and local 
governments, the EPA has already consulted extensively with state air 
agency officials prior to this proposal. The EPA specifically solicits 
comments on this proposed action from state and local officials. In 
addition, the EPA intends to meet with organizations representing state 
and local officials during the comment period for this action.

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

    This proposed action does not have tribal implications as specified 
in Executive Order 13175. It would not have a substantial direct effect 
on one or more Indian tribes. Furthermore, these proposed regulation 
revisions do not affect the relationship or distribution of power and 
responsibilities between the federal government and Indian tribes. The 
CAA and the TAR establish the relationship of the federal government 
and tribes in characterizing air quality and developing plans to 
protect visibility in Class I areas. Thus, Executive Order 13175 does 
not apply to this action.
    Although Executive Order 13175 does not apply to this action, the 
EPA solicits comment on this proposed action from tribal officials. The 
EPA also intends to offer to consult with any tribal government to 
discuss this proposal. See also Section III.B.5 of this document for 
further discussion regarding the role of tribes in visibility 
protection.

G. Executive Order 13045: Protection of Children From Environmental 
Health 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 a ``significant energy action'' because it is 
not likely to have a significant adverse effect on the supply, 
distribution or use of energy.

I. National Technology Transfer and Advancement Act

    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 believes the human health or environmental risk addressed 
by this action will not have disproportionately high and adverse human 
health or environmental effects on minority, low-income or indigenous 
populations. The results of our evaluation are contained in Section V 
of this document.

VII. Statutory Authority

    The statutory authority for this action is provided by 42 U.S.C. 
7403, 7407, 7410 and 7601.

List of Subjects

40 CFR Part 51

    Environmental protection, Administrative practice and procedure, 
Air pollution control, Nitrogen dioxide, Particulate matter, Sulfur 
oxides, Transportation, Volatile organic compounds.

[[Page 26969]]

40 CFR Part 52

    Environmental protection, Administrative practice and procedure, 
Air pollution control, Incorporation by reference, Nitrogen dioxide, 
Particulate matter, Sulfur oxides, Transportation, Volatile organic 
compounds.

    Dated: April 25, 2016.
Gina McCarthy,
Administrator.

    For the reasons stated in the preamble, Title 40, Chapter I of the 
Code of Federal Regulations is proposed to be amended as follows:

PART 51--REQUIREMENTS FOR PREPARATION, ADOPTION, AND SUBMITTAL OF 
IMPLEMENTATION PLANS

0
1. The authority citation for part 51 continues to read as follows:

    Authority:  23 U.S.C. 101; 42 U.S.C. 7401-7671q.

0
2. In Sec.  51.300, revise paragraph (b) to read as follows:

Sec.  51.300  Purpose and applicability.

* * * * *
    (b) Applicability--The provisions of this subpart are applicable to 
all States as defined in section 302(d) of the Clean Air Act (CAA) 
except Guam, Puerto Rico, American Samoa, and the Northern Mariana 
Islands.
* * * * *
0
3. In Sec.  51.301:
0
a. Add a definition for ``Clearest days;''
0
b. Revise the definition of ``Deciview;''
0
c. Add definitions for ``Deciview index'' and ``End of the applicable 
implementation period;''
0
d. Revise the definitions of ``Federal Class I area,'' ``Least impaired 
days,'' ``Mandatory Class I Federal Area,'' and ``Most impaired days;''
0
e. Add definitions for '' ``Natural visibility conditions'' and 
``Prescribed fire;''
0
f. Revise the definition of ``Reasonably attributable;''
0
g. Add a definition for ``Visibility;''
0
h. Revise the definitions of ``Visibility impairment;'' and
0
i. Add definitions for ``Wildfire,'' and ``Wildland.''
    The revisions and additions read as follows:

Sec.  51.301  Definitions.

* * * * *
    Clearest days means the twenty percent of monitored days in a 
calendar year with the lowest values of the deciview index.
    Deciview is the unit of measurement on the deciview index scale for 
quantifying in a standard manner human perceptions of visibility.
    Deciview index means a value for a day that is derived from 
calculated or measured light extinction, such that uniform increments 
of the index correspond to uniform incremental changes in perception 
across the entire range of conditions, from pristine to very obscured. 
The deciview index is calculated based on the following equation (for 
the purposes of calculating deciview using IMPROVE data, the 
atmospheric light extinction coefficient must be calculated from 
aerosol measurements and an estimate of Rayleigh scattering):
    Deciview index=10 ln (bext/10 Mm-1).
    bext=the atmospheric light extinction coefficient, 
expressed in inverse megameters (Mm-1).
    End of the applicable implementation period means December 31 of 
the year in which the next periodic comprehensive implementation plan 
revision is due under Sec.  51.308(f).
* * * * *
    Federal Class I area or Class I Federal area means any Federal land 
that is classified or reclassified Class I. Mandatory Federal Class I 
areas are identified in part 81, subpart D. Other Federal Class I areas 
are identified in part 52 of this title.
* * * * *
    Least impaired days means the twenty percent of monitored days in a 
calendar year with the lowest amounts of visibility impairment.
* * * * *
    Mandatory Class I Federal Area or Mandatory Federal Class I Area 
means any area identified in part 81, subpart D of this title.
    Most impaired days means the twenty percent of monitored days in a 
calendar year with the highest amounts of visibility impairment.
* * * * *
    Natural visibility conditions means visibility (contrast, 
coloration, and texture) that would have existed under natural 
conditions. Natural visibility conditions vary with time and location, 
and are estimated or inferred rather than directly measured.
* * * * *
    Prescribed fire means any fire intentionally ignited by management 
actions in accordance with applicable laws, policies, and regulations 
to meet specific land or resource management objectives.
* * * * *
    Reasonably attributable means attributable by visual observation or 
any other appropriate technique.
* * * * *
    Visibility means the degree of perceived clarity when viewing 
objects at a distance. Visibility includes perceived changes in 
contrast, coloration, and texture of elements in a scene.
    Visibility impairment means any humanly perceptible difference 
between actual visibility conditions and natural visibility conditions. 
Because natural visibility conditions can only be estimated or 
inferred, visibility impairment also is estimated or inferred rather 
than directly measured.
* * * * *
    Wildfire means any fire started by an unplanned ignition caused by 
lightning; volcanoes; other acts of nature; unauthorized activity; or 
accidental, human-caused actions, or a prescribed fire that has been 
declared to be a wildfire. A wildfire that predominantly occurs on 
wildland is a natural event.
    Wildland means an area in which human activity and development is 
essentially non-existent, except for roads, railroads, power lines, and 
similar transportation facilities. Structures, if any, are widely 
scattered.
* * * * *
0
4. Revise Sec.  51.302, to read as follows:

Sec.  51.302  Reasonably attributable visibility impairment.

    (a) The affected Federal Land Manager may certify, at any time, 
that there exists reasonably attributable impairment of visibility in 
any mandatory Class I Federal area and identify which single source or 
small number of sources is responsible for such impairment. The 
affected Federal Land Manager will provide the certification to the 
State in which the impairment occurs and the State(s) in which the 
source(s) is located.
    (b) The State(s) in which the source(s) is located shall revise its 
regional haze implementation plan, in accordance with the schedules set 
forth in paragraphs (d)(1) and (2) of this section, to include for each 
source or small number of sources that the Federal Land Manager has 
identified in whole or in part for reasonably attributable visibility 
impairment as part of a certification under paragraph (a) of this 
section:
    (1) A determination, based on the factors set forth in Sec.  
51.308(d)(1)(i)(A), of the control measures, if any, that are necessary 
with respect to the source or sources in order for the plan to make 
reasonable progress toward natural visibility conditions in the 
affected Class I Federal area;

[[Page 26970]]

    (2) Emission limitations that reflect the degree of emission 
reduction achievable by such control measures and schedules for 
compliance as expeditiously as practicable; and
    (3) Monitoring, recordkeeping, and reporting requirements 
sufficient to ensure the enforceability of the emission limitations.
    (c) If a source that the Federal Land Manager has identified as 
responsible in whole or in part for reasonably attributable visibility 
impairment as part of a certification under paragraph (a) of this 
section is a BART-eligible source, and if there is not in effect as of 
the date of the certification a fully or conditionally approved 
implementation plan addressing the BART requirement for that source 
(which existing plan may incorporate either source-specific emission 
limitations reflecting the emission control performance of BART, an 
alternative program to address the BART requirement under Sec.  
51.308(e)(2), (3), and (4), or for sources of SO2 a program 
approved under paragraph Sec.  51.309(d)(4)), then the State shall 
revise its regional haze implementation plan to meet the requirements 
of Sec.  51.308(e) with respect to that source, taking into account 
current conditions related to the factors listed in Sec.  
51.308(e)(1)(ii)(A). This requirement is in addition to the requirement 
of paragraph (b) of this section.

Proposed Paragraph (d): Option One

    (d) For any existing reasonably attributable visibility impairment 
the Federal Land Manager certifies to the State(s) under paragraph (a) 
of this section, the State(s) shall submit a revision to its regional 
haze implementation plan that includes the elements described in 
paragraph (b) and
    (c) no later than 3 years after the date of the certification. The 
State(s) is not required at that time to also revise its reasonable 
progress goals to reflect the additional emission reductions required 
from the source or sources.]

Proposed Paragraph (d): Option Two

    (d) For any existing reasonably attributable visibility impairment 
the Federal Land Manager certifies to the State(s) under paragraph (a) 
of this section more than 2 years prior to the due date for a regional 
haze implementation plan revision required under Sec.  51.308(f) or the 
due date for a regional haze progress report required under Sec.  
51.308(g), the State(s) shall include the elements described in 
paragraphs (b) and (c) in a plan revision by the due date for that 
implementation plan revision as part of such revision or by the due 
date for the progress report, whichever is due first, provided that the 
earlier date is at least 2 years after the certification. For plan 
revisions submitted by the due date for the progress report, the 
State(s) is not required at that time to also revise its reasonable 
progress goals to reflect the additional emission reductions required 
from the source or sources.]

Proposed Paragraph (d): Option Three

    (d)(1) For any existing reasonably attributable visibility 
impairment the Federal Land Manager certifies to the State(s) under 
paragraph (a) of this section more than 2 years prior to the due date 
for a regional haze implementation plan revision required under Sec.  
51.308(f), the State(s) shall include the elements described in 
paragraphs (b) and (c) in such revision and such elements shall be 
considered a required part of such revision.
    (2) For any existing reasonably attributable visibility impairment 
the Federal Land Manager certifies to the State(s) under paragraph (a) 
of this section less than 2 years prior to the due date for a regional 
haze implementation plan revision required under Sec.  51.308(f), but 
no more than 6 months subsequent to the submission date of that 
implementation plan revision or no more than 6 months subsequent to a 
further plan revision that changes the emission limitation for the 
subject source, the State(s) shall submit a revision to its regional 
haze implementation plan that includes the elements described in 
paragraph (b) and (c) no later than 2 years after the date of the 
certification. The State(s) is not required at that time to also revise 
its reasonable progress goals to reflect the additional emission 
reductions required from the source or sources.]

0
5. Revise Sec.  51.304 to read as follows:

Sec.  51.304  Identification of integral vistas.

    (a) Federal Land Managers were required to identify any integral 
vistas on or before December 31, 1985, according to criteria the 
Federal Land Managers developed. These criteria must have included, but 
were not limited to, whether the integral vista was important to the 
visitor's visual experience of the mandatory Class I Federal area.
    (b) The following integral vistas were identified by Federal Land 
Managers: at Roosevelt Campobello International Park, from the 
observation point of Roosevelt cottage and beach area, the viewing 
angle from 244 to 256 degrees; and at Roosevelt Campobello 
International Park, from the observation point of Friar's Head, the 
viewing angle from 154 to 194 degrees.
    (c) The State must list in its implementation plan any integral 
vista listed in paragraph (b) of this section.
    (d) [Reserved]
0
6. Section 51.305 is revised to read as follows:

Sec.  51.305  Monitoring for reasonably attributable visibility 
impairment.

    For the purposes of addressing reasonably attributable visibility 
impairment, if the Administrator, Regional Administrator, or the 
affected Federal Land Manager has advised a State containing a 
mandatory Class I Federal area of a need for monitoring to assess 
reasonably attributable visibility impairment at a mandatory Class I 
Federal area in addition to the monitoring currently being conducted to 
meet the requirements of Sec.  51.308(d)(4), the State must include in 
the next implementation plan revision to meet the requirement of Sec.  
51.308(f) an appropriate strategy for evaluating reasonably 
attributable visibility impairment in the mandatory Class I Federal 
area by visual observation or other appropriate monitoring techniques. 
Such strategy must take into account current and anticipated visibility 
monitoring research, the availability of appropriate monitoring 
techniques, and such guidance as is provided by the Agency.

Sec.  51.306  [Removed and Reserved]

0
7. Section 51.306 is removed and reserved.
0
8. In Sec.  51.307, revise paragraphs (a) introductory text and (b)(1) 
and (2) to read as follows:

Sec.  51.307  New source review.

    (a) For purposes of new source review of any new major stationary 
source or major modification that would be constructed in an area that 
is designated attainment or unclassified under section 107(d) of the 
CAA, the State plan must, in any review under Sec.  51.166 with respect 
to visibility protection and analyses, provide for:
* * * * *
    (b) * * *
    (1) That may have an impact on any integral vista of a mandatory 
Class I Federal area listed in Sec.  51.304(b), or
    (2) That proposes to locate in an area classified as nonattainment 
under section 107(d)(1) of the Clean Air Act that may have an impact on 
visibility in any mandatory Class I Federal area.
* * * * *
0
9. In Sec.  51.308:
0
a. Revise paragraph (b);
0
b. Add paragraph (c);
0
c. Revise paragraphs (d)(2)(iv), (d)(3), (e)(2)(v), (e)(4) and (5), and 
(f);

[[Page 26971]]

0
d. Revise paragraphs (g) introductory text, (g)(3) through (7), (h) 
introductory text, (h)(1), (i)(2) introductory text, and (i)(3) and 
(4).
    The revisions and additions read as follows:

Sec.  51.308  Regional haze program requirements.

* * * * *
    (b) When are the first implementation plans due under the regional 
haze program? Except as provided in Sec.  51.309(c), each State 
identified in Sec.  51.300(b) must submit, for the entire State, an 
implementation plan for regional haze meeting the requirements of 
paragraphs (d) and (e) of this section no later than December 17, 2007.
    (c) What is the relationship between requirements for regional haze 
and requirements for reasonably attributable visibility impairment? A 
State must address any reasonably attributable visibility impairment 
certified by a Federal Land Manager under Sec.  51.302(a) in its 
regional haze implementation plan, as required by Sec.  51.302(b)-(d). 
A State must also meet the requirements of Sec.  51.305 if the 
Administrator, Regional Administrator, or the Federal Land Manager has 
advised a State under Sec.  51.305 of a need for additional monitoring 
to assess reasonably attributable visibility impairment at a mandatory 
Class I Federal area.
    (d) * * *
    (2) * * *
    (iv) For the first implementation plan addressing the requirements 
of paragraphs (d) and (e) of this section, the number of deciviews by 
which baseline conditions exceed natural visibility conditions for the 
most impaired and least impaired days.
    (3) Long-term strategy for regional haze. Each State listed in 
Sec.  51.300(b) must submit a long-term strategy that addresses 
regional haze visibility impairment for each mandatory Class I Federal 
area within the State and for each mandatory Class I Federal area 
located outside the State that may be affected by emissions from the 
State. The long-term strategy must include enforceable emissions 
limitations, compliance schedules, and other measures as necessary to 
achieve the reasonable progress goals established by States having 
mandatory Class I Federal areas. In establishing its long-term strategy 
for regional haze, the State must meet the following requirements:
* * * * *
    (e) * * *
    (2) * * *
    (v) At the State's option, a provision that the emissions trading 
program or other alternative measure may include a geographic 
enhancement to the program to address the requirement under Sec.  
51.302(b) related to reasonably attributable impairment from the 
pollutants covered under the emissions trading program or other 
alternative measure.
* * * * *
    (4) A State subject to a trading program established in accordance 
with Sec.  52.38 or Sec.  52.39 under a Transport Rule Federal 
Implementation Plan need not require BART-eligible fossil fuel-fired 
steam electric plants in the State to install, operate, and maintain 
BART for the pollutant covered by such trading program in the State. A 
State that chooses to meet the emission reduction requirements of the 
Transport Rule by submitting a SIP revision that establishes a trading 
program and is approved as meeting the requirements of Sec.  52.38 or 
Sec.  52.39 also need not require BART-eligible fossil fuel-fired steam 
electric plants in the State to install, operate, and maintain BART for 
the pollutant covered by such trading program in the State. A State may 
adopt provisions, consistent with the requirements applicable to the 
State for a trading program established in accordance with Sec.  52.38 
or Sec.  52.39 under the Transport Rule Federal Implementation Plan or 
established under a SIP revision that is approved as meeting the 
requirements of Sec.  52.38 or Sec.  52.39, for a geographic 
enhancement to the program to address any requirement under Sec.  
51.302(b) related to reasonably attributable impairment from the 
pollutant covered by such trading program in that State.
    (5) After a State has met the requirements for BART or implemented 
emissions trading program or other alternative measure that achieves 
more reasonable progress than the installation and operation of BART, 
BART-eligible sources will be subject to the requirements of paragraphs 
(d) and (f) of this section, as applicable, in the same manner as other 
sources.
* * * * *
    (f) Requirements for periodic comprehensive revisions of 
implementation plans for regional haze. Each State identified in Sec.  
51.300(b) must revise and submit its regional haze implementation plan 
revision to EPA by July 31, 2021, July 31, 2028, and every 10 years 
thereafter. The plan revision due on or before July 31, 2021 must 
include a commitment by the State to meet the requirements of paragraph 
(g). In each plan revision, the State must address regional haze in 
each mandatory Class I Federal area located within the State and in 
each mandatory Class I Federal area located outside the State that may 
be affected by emissions from within the State. To meet the core 
requirements for regional haze for these areas, the State must submit 
an implementation plan containing the following plan elements and 
supporting documentation for all required analyses:
    (1) Calculations of baseline, current, and natural visibility 
conditions; progress to date; and the uniform rate of progress. For 
each mandatory Class I Federal area located within the State, the State 
must determine the following:
    (i) Baseline visibility conditions for the most impaired and 
clearest days. The period for establishing baseline visibility 
conditions is 2000 to 2004. For purposes of calculating and displaying 
the uniform rate of progress, baseline visibility conditions must be 
associated with the last day of this period. Baseline visibility 
conditions must be calculated, using available monitoring data, by 
establishing the average deciview index for the most impaired and 
clearest days for each calendar year from 2000 to 2004. The baseline 
visibility conditions are the average of these annual values. For 
mandatory Class I Federal areas without onsite monitoring data for 
2000-2004, the State must establish baseline values using the most 
representative available monitoring data for 2000-2004, in consultation 
with the Administrator or his or her designee. For mandatory Class I 
Federal areas with incomplete data availability for 2000-2004, the 
State must establish baseline values using the closest 5 complete years 
of monitoring data.
    (ii) Natural visibility conditions for the most impaired and 
clearest days. Natural visibility conditions must be calculated by 
estimating the deciview index existing under natural conditions for the 
most impaired and clearest days, based on available monitoring 
information and appropriate data analysis techniques; and
    (iii) Current visibility conditions for the most impaired and 
clearest days. The period for calculating current visibility conditions 
is the most recent 5-year period for which data are available. Current 
visibility conditions must be calculated based on the annual average 
level of visibility impairment for the most impaired and clearest days 
for each of these 5 years. Current visibility conditions are the 
average of these annual values.
    (iv) Progress to date for the most impaired and clearest days. 
Actual progress made towards natural conditions since the baseline 
period, and actual progress made during the previous implementation 
period up to and including to the period for

[[Page 26972]]

calculating current visibility conditions, for the most impaired and 
clearest days, must be calculated.
    (v) Difference between current visibility conditions and natural 
visibility conditions. The number of deciviews by which current 
visibility conditions exceed natural visibility conditions, for the 
most impaired and clearest days, must be calculated.
    (vi) Uniform rate of progress. (A) The uniform rate of progress for 
each mandatory Class I Federal area in the State must be calculated. To 
calculate this uniform rate of progress, the State must compare 
baseline visibility conditions to natural visibility conditions in the 
mandatory Class I Federal area and determine the uniform rate of 
visibility improvement (measured in deciviews of improvement per year) 
that would need to be maintained during each implementation period in 
order to attain natural visibility conditions by the end of 2064.
    (B) The State may submit a request to the Administrator seeking an 
adjustment to the uniform rate of progress for a mandatory Class I 
Federal area to account for impacts from (1) anthropogenic sources 
outside the United States and/or (2) wildland prescribed fires that 
were conducted with the objective to establish, restore, and/or 
maintain sustainable and resilient wildland ecosystems, to reduce the 
risk of catastrophic wildfires, and/or to preserve endangered or 
threatened species during which appropriate basic smoke management 
practices were applied. To calculate the proposed adjustment, the State 
must add the estimated impacts to natural visibility conditions and 
compare the resulting value to baseline visibility conditions. If the 
Administrator determines that the State has estimated the impacts from 
anthropogenic sources outside the United States or wildland prescribed 
fires using scientifically valid data and methods, the Administrator 
may approve the proposed adjustment to the uniform rate of progress for 
use in the State's implementation plan.
    (2) Long-term strategy for regional haze and reasonably 
attributable visibility impairment. Each State must submit a long-term 
strategy that addresses regional haze visibility impairment, and if 
necessary any reasonably attributable visibility impairment certified 
by the Federal Land Manager under Sec.  51.302(a), for each mandatory 
Class I Federal area within the State and for each mandatory Class I 
Federal area located outside the State that may be affected by 
emissions from the State. The long-term strategy must include the 
enforceable emissions limitations, compliance schedules, and other 
measures that are necessary to achieve reasonable progress, as 
determined pursuant to (f)(2)(i) through (vi). In establishing its 
long-term strategy for regional haze, the State must meet the following 
requirements:
    (i) The State must consider and analyze emission reduction measures 
based on 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 any potentially affected major or minor 
stationary source or group of sources. The State must document the 
criteria used to determine which sources or groups of sources were 
evaluated, and how these four factors were taken into consideration in 
selecting the measures for inclusion in its long-term strategy.
    (ii) The State must consider the uniform rate of improvement in 
visibility, the emission reduction measures identified in (f)(2)(i), 
and additional measures being adopted by other contributing states in 
(f)(2)(iii) as needed to make reasonable progress towards natural 
visibility conditions for the period covered by the implementation 
plan.
    (iii) The State must consult with those States which may reasonably 
be anticipated to cause or contribute to visibility impairment in the 
mandatory Class I Federal area.
    (A) Contributing States. Where the State has emissions that are 
reasonably anticipated to contribute to visibility impairment in any 
mandatory Class I Federal area located in another State or States, the 
State must consult with the other State(s) in order to develop 
coordinated emission management strategies. The State must demonstrate 
that it has included in its implementation plan all measures necessary 
to obtain its share of the emission reductions needed to provide for 
reasonable progress towards natural visibility conditions in the 
mandatory Class I Federal area located in the other State or States. If 
the State has participated in a regional planning process, the State 
must also ensure that it has included all measures needed to achieve 
its apportionment of emission reduction obligations agreed upon through 
that process.
    (B) States affected by contributing States. A State with a 
mandatory Class I Federal area must consult with any other State having 
emissions that are reasonably anticipated to contribute to visibility 
impairment in that area regarding the emission reductions needed in 
each State to provide for reasonable progress towards natural 
visibility conditions in that area. If the State has participated in a 
regional planning process, the State must ensure it has included all 
measures needed to achieve its apportionment of emission reduction 
obligations agreed upon through that process.
    (C) In any situation in which a State cannot agree with another 
State or group of States on the emission reductions needed for 
reasonable progress towards natural visibility conditions in any 
mandatory Class I Federal area, each involved State must describe in 
its submittal the actions taken to resolve the disagreement. In 
reviewing the State's implementation plan submittal, the Administrator 
will take this information into account in determining whether the 
State's implementation plan provides for reasonable progress towards 
natural visibility conditions at each mandatory Class I Federal area 
that is located in the State or that may be affected by emissions from 
the State. All substantive interstate consultations must be documented.
    (iv) As part of the demonstration required by (f)(2)(i), the State 
must document the technical basis, including information on the factors 
listed in (f)(2)(i) and modeling, monitoring, and emissions 
information, on which the State is relying to determine the emission 
reductions from anthropogenic sources in the State that are necessary 
for achieving reasonable progress towards natural visibility conditions 
in each mandatory Class I Federal area it affects. The State may meet 
this requirement by relying on technical analyses developed by a 
regional planning process and approved by all State participants. The 
State must identify the baseline emissions inventory on which its 
strategies are based. The baseline emissions inventory year shall be 
the most recent year for which the State has submitted emission 
inventory information to the Administrator in compliance with the 
triennial reporting requirements of subpart A of this part unless the 
State adequately justifies the use of another inventory year.
    (v) The State must identify all anthropogenic sources of visibility 
impairment considered by the State in developing its long-term strategy 
and the criteria used to select the sources considered. The State 
should consider major and minor stationary sources, mobile sources, and 
area sources.
    (vi) The State must consider, at a minimum, the following factors 
in developing its long-term strategy:
    (A) Emission reductions due to ongoing air pollution control 
programs, including measures to address

[[Page 26973]]

reasonably attributable visibility impairment;
    (B) Measures to mitigate the impacts of construction activities;
    (C) Emissions limitations and schedules for compliance to achieve 
the reasonable progress goal;
    (D) Source retirement and replacement schedules;
    (E) Basic smoke management practices for prescribed fire used for 
agricultural and wildland vegetation management purposes and smoke 
management programs as currently exist within the State for these 
purposes;
    (F) Enforceability of emissions limitations and control measures; 
and
    (G) The anticipated net effect on visibility due to projected 
changes in point, area, and mobile source emissions over the period 
addressed by the long-term strategy.
    (3) Reasonable progress goals. (i) A state in which a mandatory 
Class I Federal area is located must establish reasonable progress 
goals (expressed in deciviews) that reflect the visibility conditions 
that are projected to be achieved by the end of the applicable 
implementation period as a result of all enforceable emissions 
limitations, compliance schedules, and other measures required under 
paragraph (f)(2) and the implementation of other requirements of the 
CAA. The long-term strategy and the reasonable progress goals must 
provide for an improvement in visibility for the most impaired days and 
ensure no degradation in visibility for the clearest days since the 
baseline period.
    (ii)(A) If a State in which a mandatory Class I Federal area is 
located establishes a reasonable progress goal for the most impaired 
days that provides for a slower rate of improvement in visibility than 
the uniform rate of progress calculated under paragraph (f)(1)(vi) of 
this section, the State must demonstrate, based on the analysis 
required by paragraph (f)(2)(i) of this section, that there are no 
additional emission reduction measures for anthropogenic sources or 
groups of sources in the State that may reasonably be anticipated to 
contribute to visibility impairment in the Class I area that would be 
reasonable to include in the long-term strategy. The State must provide 
a robust demonstration, including documenting the criteria used to 
determine which sources or groups of sources were evaluated and how the 
four factors required by paragraph (f)(2)(i) were taken into 
consideration in selecting the measures for inclusion in its long-term 
strategy. The State must provide to the public for review as part of 
its implementation plan an assessment of the number of years it would 
take to attain natural visibility conditions if visibility improvement 
were to continue at the rate of progress selected by the State as 
reasonable for the implementation period.
    (B) If a State contains sources which are reasonably anticipated to 
contribute to visibility impairment in a mandatory Class I Federal area 
in another State for which a demonstration by the other State is 
required under (f)(3)(ii)(A), the State must demonstrate that there are 
no additional emission reduction measures for anthropogenic sources or 
groups of sources in the State that may reasonably be anticipated to 
contribute to visibility impairment in the Class I area that would be 
reasonable to include in its own long-term strategy.
    (iii) The reasonable progress goals established by the State are 
not directly enforceable but will be considered by the Administrator in 
evaluating the adequacy of the measures in the implementation plan in 
providing for reasonable progress towards achieving natural visibility 
conditions at that area.
    (iv) In determining whether the State's goal for visibility 
improvement provides for reasonable progress towards natural visibility 
conditions, the Administrator will also evaluate the demonstrations 
developed by the State pursuant to paragraphs (f)(2) and (f)(3)(ii)(A) 
of this section and the demonstrations provided by other States 
pursuant to paragraphs (f)(2) and (f)(3)(ii)(B) of this section.
    (4) If the Administrator, Regional Administrator, or the affected 
Federal Land Manager has advised a State of a need for additional 
monitoring to assess reasonably attributable visibility impairment at a 
mandatory Class I Federal area in addition to the monitoring currently 
being conducted, the State must include in the plan revision an 
appropriate strategy for evaluating reasonably attributable visibility 
impairment in the mandatory Class I Federal area by visual observation 
or other appropriate monitoring techniques.
    (5) So that the plan revision will serve also as a progress report, 
the State must address in the plan revision the requirements of 
paragraphs (g)(1) through (5) of this section. However, the period to 
be addressed for these elements shall be the period since the past 
progress report.
    (6) Monitoring strategy and other implementation plan requirements. 
The State must submit with the implementation plan a monitoring 
strategy for measuring, characterizing, and reporting of regional haze 
visibility impairment that is representative of all mandatory Class I 
Federal areas within the State. Compliance with this requirement may be 
met through participation in the Interagency Monitoring of Protected 
Visual Environments network. The implementation plan must also provide 
for the following:
    (i) The establishment of any additional monitoring sites or 
equipment needed to assess whether reasonable progress goals to address 
regional haze for all mandatory Class I Federal areas within the State 
are being achieved.
    (ii) Procedures by which monitoring data and other information are 
used in determining the contribution of emissions from within the State 
to regional haze visibility impairment at mandatory Class I Federal 
areas both within and outside the State.
    (iii) For a State with no mandatory Class I Federal areas, 
procedures by which monitoring data and other information are used in 
determining the contribution of emissions from within the State to 
regional haze visibility impairment at mandatory Class I Federal areas 
in other States.
    (iv) The implementation plan must provide for the reporting of all 
visibility monitoring data to the Administrator at least annually for 
each mandatory Class I Federal area in the State. To the extent 
possible, the State should report visibility monitoring data 
electronically.
    (v) A statewide inventory of emissions of pollutants that are 
reasonably anticipated to cause or contribute to visibility impairment 
in any mandatory Class I Federal area. The inventory must include 
emissions for a baseline year, emissions for the most recent year for 
which data are available, and estimates of future projected emissions. 
The State must also include a commitment to update the inventory 
periodically.
    (vi) Other elements, including reporting, recordkeeping, and other 
measures, necessary to assess and report on visibility.
    (g) Requirements for periodic reports describing progress towards 
the reasonable progress goals. Each State identified in Sec.  51.300(b) 
must periodically submit a report to the Administrator evaluating 
progress towards the reasonable progress goal for each mandatory Class 
I Federal area located within the State and in each mandatory Class I 
Federal area located outside the State that may be affected by 
emissions from within the State. The first progress report is due 5 
years from submittal of the initial implementation plan addressing 
paragraphs (d) and (e) of this section. The first progress reports must 
be in the form of implementation

[[Page 26974]]

plan revisions that comply with the procedural requirements of Sec.  
51.102 and Sec.  51.103. Subsequent progress reports are due by January 
31, 2025, July 31, 2033, and every 10 years thereafter. Subsequent 
progress reports must be made available for public inspection and 
comment for at least 60 days prior to submission to EPA and all 
comments received from the public must be submitted to EPA along with 
the subsequent progress report, along with an explanation of any 
changes to the progress report made in response to these comments. 
Periodic progress reports must contain at a minimum the following 
elements:
* * * * *
    (3) For each mandatory Class I Federal area within the State, the 
State must assess the following visibility conditions and changes, with 
values for most impaired, least impaired and/or clearest days as 
applicable expressed in terms of 5-year averages of these annual 
values. The period for calculating current visibility conditions is the 
most recent 5-year period preceding the required date of the progress 
report for which data are available as of a date 6 months preceding the 
required date of the progress report.
    (i)(A) Progress reports due before January 31, 2025. The current 
visibility conditions for the most impaired and least impaired days.
    (B) Progress reports due on and after January 31, 2025. The current 
visibility conditions for the most impaired and clearest days;
    (ii)(A) Progress reports due before January 31, 2025. The 
difference between current visibility conditions for the most impaired 
and least impaired days and baseline visibility conditions.
    (B) Progress reports due on and after January 31, 2025. The 
difference between current visibility conditions for the most impaired 
and clearest days and baseline visibility conditions.
    (iii)(A) Progress reports due before January 31, 2025. The change 
in visibility impairment for the most impaired and least impaired days 
over the period since the period addressed in the most recent plan 
required under paragraph (f) of this section.
    (B) Progress reports due on and after January 31, 2025. The change 
in visibility impairment for the most impaired and clearest days over 
the period since the period addressed in the most recent plan required 
under paragraph (f) of this section.
    (4) An analysis tracking the change over the period since the 
period addressed in the most recent plan required under paragraph (f) 
of this section in emissions of pollutants contributing to visibility 
impairment from all sources and activities within the State. Emissions 
changes should be identified by type of source or activity. With 
respect to all sources and activities, the analysis must extend at 
least through the most recent year for which the state has submitted 
emission inventory information to the Administrator in compliance with 
the triennial reporting requirements of subpart A of this part. With 
respect to sources that report directly to a centralized emissions data 
system operated by the Administrator, the analysis must extend through 
the most recent year for which the Administrator has provided a State-
level summary of such reported data or an internet-based tool by which 
the State may obtain such a summary. The State is not required to 
backcast previously reported emissions to be consistent with more 
recent emissions estimation procedures, and may draw attention to 
actual or possible inconsistencies created by changes in estimation 
procedures.
    (5) An assessment of any significant changes in anthropogenic 
emissions within or outside the State that have occurred since the 
period addressed in the most recent plan required under paragraph (f) 
of this section including whether or not these changes in anthropogenic 
emissions were anticipated in that most recent plan and whether they 
have limited or impeded progress in reducing pollutant emissions and 
improving visibility.
    (6) For a state with a long-term strategy that includes a smoke 
management program for prescribed fires on wildland, a summary of the 
most recent periodic assessment of the smoke management program 
including conclusions that were reached in the assessment as to whether 
the program is meeting its goals regarding improving ecosystem health 
and reducing the damaging effects of catastrophic wildfires.
    (7) An assessment of whether the current implementation plan 
elements and strategies are sufficient to enable the State, or other 
States with mandatory Class I Federal areas affected by emissions from 
the State, to meet all established reasonable progress goals for the 
period covered by the most recent plan required under paragraph (f) of 
this section.
    (h) Determination of the adequacy of existing implementation plan. 
At the same time the State is required to submit any progress report to 
EPA in accordance with paragraph (g) of this section, the State must 
also take one of the following actions based upon the information 
presented in the progress report:
    (1) If the State determines that the existing implementation plan 
requires no further substantive revision at this time in order to 
achieve established goals for visibility improvement and emissions 
reductions, the State must provide to the Administrator a declaration 
that revision of the existing implementation plan is not needed at this 
time.
* * * * *
    (i) * * *
    (2) The State must provide the Federal Land Manager with an 
opportunity for consultation, in person at a point early enough in the 
State's technical and policy analyses of its long-term strategy 
emission reduction obligation and prior to development of reasonable 
progress goals so that information and recommendations provided by the 
Federal Land Manager can meaningfully inform the State's development of 
the long-term strategy. The opportunity for consultation will be deemed 
to have been early enough if the consultation has taken place at least 
120 days prior to holding any public hearing or other public comment 
opportunity on an implementation plan (or plan revision) or progress 
report for regional haze required by this subpart. The opportunity for 
consultation must be provided no less than 60 days prior to said public 
hearing or public comment opportunity. This consultation must include 
the opportunity for the affected Federal Land Managers to discuss 
their:
* * * * *
    (3) In developing any implementation plan (or plan revision) or 
progress report, the State must include a description of how it 
addressed any comments provided by the Federal Land Managers.
    (4) The plan (or plan revision) must provide procedures for 
continuing consultation between the State and Federal Land Manager on 
the implementation of the visibility protection program required by 
this subpart, including development and review of implementation plan 
revisions and progress reports, and on the implementation of other 
programs having the potential to contribute to impairment of visibility 
in mandatory Class I Federal areas.

0
10. In Sec.  51.309, revise paragraphs (d)(4)(v), (d)(10) introductory 
text, (d)(10)(i) introductory text, (d)(10)(ii) introductory text, add 
paragraphs (d)(10)(iii) and(iv), and revise paragraph (g)(2)(iii) to 
read as follows:

[[Page 26975]]

Sec.  51.309  Requirements related to the Grand Canyon Visibility 
Transport Commission.

* * * * *
    (d) * * *
    (4) * * *
    (v) Market Trading Program. The implementation plan must include 
requirements for a market trading program to be implemented in the 
event that a milestone is not achieved. The plan shall require that the 
market trading program be activated beginning no later than 15 months 
after the end of the first year in which the milestone is not achieved. 
The plan shall also require that sources comply, as soon as 
practicable, with the requirement to hold allowances covering their 
emissions. Such market trading program must be sufficient to achieve 
the milestones in paragraph (d)(4)(i) of this section, and must be 
consistent with the elements for such programs outlined in Sec.  
51.308(e)(2)(vi). Such a program may include a geographic enhancement 
to the program to address the requirement under Sec.  51.302(b) related 
to reasonably attributable impairment from the pollutants covered under 
the program.
* * * * *
    (10) Periodic implementation plan revisions and progress reports. 
Each Transport Region State must submit to the Administrator periodic 
reports in the years 2013 and as specified for subsequent progress 
reports in Sec.  51.308(g). The progress report due in 2013 must be in 
the form of an implementation plan revision that complies with the 
procedural requirements of Sec. Sec.  51.102 and 51.103.
    (i) The report due in 2013 will assess the area for reasonable 
progress as provided in this section for mandatory Class I Federal 
area(s) located within the State and for mandatory Class I Federal 
area(s) located outside the State that may be affected by emissions 
from within the State. This demonstration may be based on assessments 
conducted by the States and/or a regional planning body. The progress 
report due in 2013 must contain at a minimum the following elements:
* * * * *
    (ii) At the same time the State is required to submit the 5-year 
progress report due in 2013 to EPA in accordance with paragraph 
(d)(10)(i) of this section, the State must also take one of the 
following actions based upon the information presented in the progress 
report:
* * * * *
    (iii) The requirements of Sec.  51.308(g) regarding requirements 
for periodic reports describing progress towards the reasonable 
progress goals apply to States submitting plans under this section, 
with respect to subsequent progress reports due after 2013.
    (iv) The requirements of Sec.  51.308(h) regarding determinations 
of the adequacy of existing implementation plans apply to States 
submitting plans under this section, with respect to subsequent 
progress reports due after 2013.
* * * * *
    (g) * * *
    (2) * * *
    (iii) The Transport Region State may consider whether any 
strategies necessary to achieve the reasonable progress goals required 
by paragraph (g)(2) of this section are incompatible with the 
strategies implemented under paragraph (d) of this section to the 
extent the State adequately demonstrates that the incompatibility is 
related to the costs of the compliance, the time necessary for 
compliance, the energy and non air quality environmental impacts of 
compliance, or the remaining useful life of any existing source subject 
to such requirements.

PART 52--APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS

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

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

Sec.  52.26  [Removed and Reserved]

0
12. Section 52.26 is removed and reserved.

Sec.  52.29  [Removed and Reserved]

0
13. Section 52.29 is removed and reserved.

Sec.  52.61  [Amended]

0
14. In Sec.  52.61, remove and reserve paragraph (b).
0
15. In Sec.  52.145, revise paragraph (b) and remove and reserve 
paragraph (c).
    The revision reads as follows:

Sec.  52.145  Visibility protection.

* * * * *
    (b) Regulations for visibility monitoring and new source review. 
The provisions of Sec. Sec.  52.27 and 52.28 are hereby incorporated 
and made part of the applicable plan for the State of Arizona.
* * * * *

Sec.  52.281  [Amended]

0
16. In Sec.  52.281, remove and reserve paragraphs (b) and (e).
0
17. In Sec.  52.344, revise paragraph (b) to read as follows:

Sec.  52.344  Visibility protection.

* * * * *
    (b) The Visibility NSR regulations are approved for industrial 
source categories regulated by the NSR and PSD regulations which have 
previously been approved by EPA. However, Colorado's NSR and PSD 
regulations have been disapproved for certain sources as listed in 40 
CFR 52.343(a)(1). The provisions of 40 CFR 52.28 are hereby 
incorporated and made a part of the applicable plan for the State of 
Colorado for these sources.
0
18. In Sec.  52.633, revise paragraph (b) and remove and reserve 
paragraph (c).
    The revision reads as follows:

Sec.  52.633  Visibility protection.

* * * * *
    (b) Regulations for visibility monitoring and new source review. 
The provisions of Sec. Sec.  52.27 and 52.28 are hereby incorporated 
and made part of the applicable plan for the State of Hawaii.
* * * * *

Sec.  52.690  [Amended]

0
19. In Sec.  52.690, remove and reserve paragraphs (b) and (c).

Sec.  52.1033  [Amended]

0
20. In Sec.  52.1033, remove and reserve paragraphs (a) and (c).
0
21. In Sec.  52.1183, revise paragraph (b) and remove and reserve 
paragraphs (a) and (c).
    The revision reads as follows:

Sec.  52.1183  Visibility protection.

* * * * *
    (b) Regulation for visibility monitoring and new source review. The 
provisions of Sec.  52.28 are hereby incorporated and made a part of 
the applicable plan for the State of Michigan.
* * * * *
0
22. In Sec.  52.1236, revise paragraph (b) remove and reserve paragraph 
(c).
    The revision reads as follows:

Sec.  52.1236  Visibility protection.

* * * * *
    (b) Regulation for visibility monitoring and new source review. The 
provisions of Sec.  52.28 are hereby incorporated and made a part of 
the applicable plan for the State of Minnesota.
* * * * *

Sec.  52.1339  [Amended]

0
23. In Sec.  52.1339, remove and reserve paragraph (b).

Sec.  52.1387  [Amended]

0
24. In Sec.  52.1387, remove and reserve paragraph (b).

[[Page 26976]]

0
25. In Sec.  52.1488, revise paragraph (b) and remove and reserve 
paragraph (c).
    The revision reads as follows:

Sec.  52.1488  Visibility protection.

* * * * *
    (b) Regulation for visibility monitoring and new source review. The 
provisions of Sec.  52.28 are hereby incorporated and made a part of 
the applicable plan for the State of Nevada except for that portion 
applicable to the Clark County Department of Air Quality and 
Environmental Management.
* * * * *
0
26. In Sec.  52.1531, revise paragraph (b) and remove and reserve 
paragraph (c).
    The revision reads as follows:

Sec.  52.1531  Visibility protection.

* * * * *
    (b) Regulation for visibility monitoring and new source review. The 
provisions of Sec.  52.28 are hereby incorporated and made a part of 
the applicable plan for the State of New Hampshire.
* * * * *

Sec.  52.2132  [Amended]

0
27. In Sec.  52.2132, remove and reserve paragraphs (b) and (c).
0
28. In Sec.  52.2179, revise paragraph (b) and remove and reserve 
paragraph (c).
    The revision reads as follows:

Sec.  52.2179  Visibility protection.

* * * * *
    (b) Regulation for visibility monitoring and new source review. The 
provisions of Sec.  52.28 are hereby incorporated and made a part of 
the applicable plan for the State of South Dakota.
* * * * *

Sec.  52.2304  [Amended]

0
29. In Sec.  52.2304, remove and reserve paragraph (b).
0
30. In Sec.  52.2383, revise paragraph (b) to read as follows:

Sec.  52.2383  Visibility protection.

* * * * *
    (b) Regulations for visibility monitoring and new source review. 
The provisions of Sec.  52.27 are hereby incorporated and made part of 
the applicable plan for the State of Vermont.

0
31. In Sec.  52.2452, revise paragraph (a) and remove and reserve 
paragraphs (b) and (c).
    The revision reads as follows:

Sec.  52.2452  Visibility protection.

    (a) Reasonably Attributable Visibility Impairment. The requirements 
of section 169A of the Clean Air Act are not met because the plan does 
not include approvable measures for meeting the requirements of 40 CFR 
51.305 for protection of visibility in mandatory Class I Federal areas.
* * * * *
0
32. In Sec.  52.2533, revise paragraphs (a) and (b) and remove and 
reserve paragraph (c).
    The revisions read as follows:

Sec.  52.2533  Visibility protection.

    (a) Reasonably Attributable Visibility Impairment. The requirements 
of section 169A of the Clean Air Act are not met because the plan does 
not include approvable measures for meeting the requirements of 40 CFR 
51.305 and 51.307 for protection of visibility in mandatory Class I 
Federal areas.
    (b) Regulation for visibility monitoring and new source review. The 
provisions of Sec.  52.28 are hereby incorporated and made a part of 
the applicable plan for the State of West Virginia.
* * * * *

Sec.  52.2781  [Amended]

0
33. In Sec.  52.2781, remove and reserve paragraphs (b) and (c).

[FR Doc. 2016-10228 Filed 5-3-16; 8:45 am]
 BILLING CODE 6560-50-P