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Environmental Protection Agency (EPA): Proposed Rule 

Protection of Visibility: Amendments to Requirements for State Plans 

RIN 2060-AS55 

General Comments: 

1) Reviewer recommends adding two sections into the preamble on the following topics: (1) 

documents related to this regulatory activity and (2) issues on which EPA seeks 

comments. The first topic should provide a list of all EPA documents referenced within 

the preamble (or important documents not referenced) with citations for where the 

information can be found. The second topic should provide a list of issues that EPA has 

specifically requested comment throughout the preamble. EPA could provide 

identification numbers and request that commenters refer to the identification number to 

ease the burden on EPA staff when reviewing public comments. By including these two 

lists, the reviewer believes that this will enhance transparency and provide clarity for 

members of the public to know where to find other related documents and what issues 

EPA specifically is taking comment on outside of the issues proposed. 

EPA’s response: No edit has been made in response to this comment. 

2) Reviewer recommends revising the term “wildfire” to the term “wildland fire” 

throughout the document except for reference to international fires for example on page 

51. The reviewer believes that this change will make the proposed rule more consistent 

with other recent and ongoing rulemaking at the nexus of air quality, land management, 

and wildland fire risk. The term “wildland fire” broadly depicts all types of fire that may 

represent a natural visibility contributing event. 

EPA’s response: An extensive insertion has been made to the preamble (new section 

IV.E) to fully address the complex topic of fire impacts on visibility and how SIPs 

should address fire-related issues. In addition, a smaller fire-related insertion has 

been made to section IV.B. Rule text changes have been made to reflect these 

preamble changes. New definitions have been added for some fire-related terms that 

would be newly used in the rule text. EPA is still considering how to condense the 

added regulatory text while preserving the substance that appears in this version. 

3) Reviewer recommends clarifying how reasonable progress requirements under 

§ 51.308(f) will be addressed for sources on tribal lands. 

EPA’s response: Text has been added to footnote 1 on page 41

 in response to this 

comment. 

4) Reviewer recommends removing the need for a separate reassessment of BART-eligible 

sources for reasonable further progress. EPA indicates in the preamble (pages 20-21) that 

the BART requirement is a one-time requirement that was applied, for the most part, 

during the first implementation phase. Nonetheless, EPA states that “BART-eligible 

sources may be reassessed for additional control measures in later implementation 

periods as part of the requirement for additional control measures in later implementation 

 

1

 Page citations refer to the redline-strikeout version of the referenced documents. 
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periods as part of the requirement to provide for reasonable progress.” (page 22) The 

regional haze rule sets out criteria that states must consider in establishing a reasonable 

progress goal for affected sources. See 40 CFR § 51.308(d)(1)(i). In establishing this 

goal, a State must consider “the costs of compliance, the energy and non-air quality 

environmental impacts of compliance, and the remaining useful life of any potentially 

affected source.” Id. At § 51.308(d)(1)(i)(A). These criteria are similar to those included 

in the definition of “best available retrofit technology.” See 40 CFR § 51.301. 

EPA’s response: The existing rule provides that BART sources should be reassessed 

under reasonable progress. EPA is not proposing to change this. However, 

explanatory text has been added on page 22 in response to this comment. 

5) Reviewer recommends that any dispute between an FLM and the State as to the validity 

of the certification should be resolved by EPA, consistent with Section 169B(d) of the 

CAA, which requires States to consult with FLMs in promulgating an implementation 

plan. 

EPA’s response: Explanatory text has been added on page 80 in response to this 

comment. 

6) Reviewer recommends clarifying whether the delay of the planning process would affect 

the pace of emission reductions. 

EPA’s response: Explanatory text has been added on page 12 in response to this 

comment. Note also that section V (Environmental Justice Considerations) of the 

preamble already addresses this question. 

a. Reviewer recommends clarifying on page 11 how the change in the planning 

timeframe is anticipated to result in greater environmental progress than in the 

status quo. 

EPA’s response: No edit has been made in response to this comment. 

b. Reviewer recommends providing additional explanation on page 12 of the 

implications of the “as needed” approach for the frequency of state planning 

efforts to address visibility impairments and why it is expected to improve 

visibility projection. 

EPA’s response: Explanatory text has been added on page 13 in response to 

this comment. 

7) Reviewer recommends providing specific number of states that have submitted SIPs 

when discussing them as this would provide the reader additional granularity and clarity 

and the number of states affected. For example, on page 17, the sentence states “Few 

states submitted a regional haze SIP by the December 17, 20007, deadline [. . .]”. 

EPA’s response: Explanatory text has been added on page 18 (in text as well as in 

footnote 7) in response to this comment. 

8) Reviewer recommends providing additional clarity on the number of additional states that 

EPA estimates would be required to take additional action due to this rule change. The 

reviewer recommends providing this both in the preamble and more explicitly within the 

Paperwork Reduction Act section with a more clear discussion of the before and after 

paperwork burden from this proposed rulemaking. 
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EPA’s response: Explanatory text has been added within the PRA section on pages 

98-99 in response to this comment. 

9) Reviewer recommends providing additional information for when the guidance document 

is planned to go out related to this rulemaking and general timelines for the draft and final 

version of the guidance. Is it possible to align the draft guidance with the proposed rule 

or to have overlap within the comment periods? 

EPA’s response: An edit has been made on this subject on page 13 of the preamble.

10) Reviewer recommends providing additional clarification on international impacts and 

their effect on states with Class I areas and states with sources contributing to Class I 

areas. 

a. Reviewer recommends proposing that international impacts not be included with 

respect to the visibility assessment and be treated the same as other background 

visibility with a condition that to include international impacts that the state must 

be able to accurately show emissions from sources internationally. This could be 

addressed through guidance in the future. Another potential alternative could be 

to treat all non-source as background, regardless of whether it was international 

and remove that from the analysis. 

EPA’s response: Text has been added on pages 55 and 56 to propose that the 

Administrator may approve “adjustments to the framework” rather than 

only taking comment, as well as proposed new rule text within section 

51.308(f)(3)(v), in response to this comment. 

b. Reviewer recommends clearly defining in the upcoming guidance the techniques 

that would be considered acceptable to account for international contributions. If 

a state sets reasonable progress goals that are not meeting the Uniform Rate of 

Progress (URP), the state could use estimates of international contribution as 

evidence to defend why additional emissions reductions are not reasonable. 

EPA’s response: No edit has been made in response to this comment. 

11) Reviewer recommends taking comment on other specific time-frames other than 6 

months as the amount of time necessary for states to incorporate the most recent available 

data into their progress reports, including 12-months, 9-months and 3-months. 

EPA’s response: Text has been added on page 71 in response to this comment. 

12) Reviewer recommends adding in the rule, preamble, or guidance that the most recently 

available information for each significant source, which may be newer for some sectors 

than for others, be used. Considering that there is typically a significant lag between the 

state's submittal of data to the National Emissions Inventory (NEI) and EPA's publication 

of that data, the reviewer recommends that the states use the most recent data they have 

submitted and not wait for EPA’s approved version of the NEI. 

EPA’s response: This will be addressed in the upcoming guidance.

13) Reviewer recommends adding “wildland fire” to the list of previously undefined terms in 

§ 51.301 and within the preamble to state:

a. Wildland fire means, for the purposes of this rule, an event and its resulting 

emissions, which may recur, that originates form wildfire or prescribed fire, 

meeting specific requirements as to contribute to the natural visibility condition. 
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EPA’s response: Definitions of wildland, wildfire and prescribed fire have 

been added to the proposed rule text, because these terms are used in the 

proposed rule and preamble text that has been added in response to general 

comment number 2.

14) Reviewer does not believe that you need to make this distinction between haze and 

impairment; haze is a relatively uniform distribution of pollutants that affects visibility. 

Contributions to haze are both natural and anthropogenic. Impairment is the relative 

contribution of anthropogenic haze to total haze. When expressed as a change in 

deciview levels, “impairment” is defined as the difference between total haze and natural 

haze. 

EPA’s response: See response to specific comment #21. 

15) Reviewer recommends retaining the original requirement for a state to respond to a 

certification within three years. This could coincide with a required SIP revision or could 

be a separate action for the certified source(s). This is a much simpler construction to 

understand and avoids the possibility of extending a state’s response up to nine and half 

years. 

EPA’s response: Text has been added on page 84 in response to this comment. 

a. Regarding the timing of a state response to a Federal Land Manager (FLM)’s 

RAVI certification, the reviewer notes that the existing 1980 portions of the 

visibility regulations considered a three year window after any certification to be 

sufficient time for a state to address reasonably attributable visibility impairment. 

Under proposed §51.302(d), the state must address the certification if made earlier 

than 2 years before SIP submittal through 6 months after SIP submittal. If the 

FLM certifies after that window, the state’s action on the certification could be as 

long as nine and a half years, after certification (Preamble, p. 64). The reviewer 

finds this proposal to be unnecessarily complex and the latter scenario to be 

“unreasonable” with respect to reasonable progress.

EPA’s response: EPA is inviting comment on keeping the existing approach, 

using the approach recommended by this interagency review comment, and 

using any other approach the public may propose. 

b. If EPA determines to coordinate the timing for state action with the next state 

implementation plan (SIP) revision, then the reviewer recommends that EPA also 

require a state to respond to certification through the midterm Regional Haze 

Progress Reports if that is closer to the timing of certification. In that case, the 

progress report would need to be submitted in the form of a SIP revision. A FLM 

RAVI certification has been and is projected to remain a rare event, but one that 

underscores a serious deficiency in a state’s strategy for abating haze causing 

pollution. 

EPA’s response: Text has been added on page 84 in response to this 

comment. 

16) Reviewer notes a discrepancy between the language on page 65 and the matching 

language on page 91. Therefore, the reviewer recommends the language which 

references actions to “submission” times as they are more relevant to active State SIP 
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engagement and FLM review. The reviewer believes that the text in question in 

§ 51.302(d)(2) should read the same as it is discussed here on page 65. 

EPA’s response: The proposed text of §51.302(d)(2) has been changed to match the 

language of preamble. 

17) Reviewer recommends clarifying the process for non-Class I states that have sources that 

affect downwind states with Class I areas. 

EPA’s response: The proposed text of §51.308(f)(3)(ii)(B) has been edited in 

response to this comment.

18) Reviewer recommends clarifying what happens if a state and a FLM do not agree on 

appropriate techniques. Specifically, page 61 states that the current implication is that 

only the state can determine what technique is appropriate; therefore, this implies that 

FLMs may use a technique that the state does not deem appropriate. EPA should clarify 

whether a state can challenge a technique that they do not deem appropriate that an FLM 

wishes to use and, if so, how reconciliation could occur. 

EPA’s response: Text has been added on page 78 in response to this comment. 

19) Reviewer recommends taking comment on specific time frames such 120 days, to consult 

the FLM prior to a public hearing that would be de facto enough time for FLM input. It 

is unclear what enough time would be for a state to provide an FLM. 

EPA’s response: See response to specific comment #34.

20) Reviewer recommends providing timeframes for how long the assessment by EPA on 

progress reports would take and what the procedures would be for the assessment. Also, 

reviewer recommends providing a negative informal consent that any modifications or 

additional steps by the state would not be required after a certain date after submittal of 

the progress report. 

EPA’s response: Text has been added on page 95 regarding EPA’s intention to 

create a logging system for progress reports.

21) Reviewer recommends revising the rule language to reflect that the preamble explicitly 

states that there is no intention to change the approach to selecting the days and that they 

will be referred to as “20 percent clearest days” related to “least impaired” days. See 

below for some additional examples: 

a. In the definitions on page 88, least impaired days should be deleted or explained 

as operationally identical to clearest days. 

b. “Least impaired days” is used in the Rule language in the following locations: 

i. Near bottom of p 86 

ii. Top of p 88 

iii. Middle of p 94 

iv. Three occurrences on p 105 

v. Top of page 106 

EPA’s response: We have added the term clearest days to the rule language to 

unambiguously identify that the days with the lowest overall deciview values are the 

days that should be used when determining whether there is visibility degradation. 

However, as the reviewer noted, we have retained the term least impaired days in the 

definitions section and have continued to use it occasionally in the rule language. 
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This is because we propose to use clearest days in the second and subsequent 

planning periods, but in order to maintain consistent terminology with SIPs (and 

progress reports) prepared for the first implementation period, we maintain the use 

of least impaired days in 51.308(d) (section covering SIPs for the first 

implementation period) and also use least impaired days when discussing the 

progress reports that cover the first implementation period (51.308(g)). We have 

added a footnote to the NPRM (footnote 25, page 50) to explain why we have not 

entirely removed least impaired days from the rule language. 

22) Reviewer understands EPA’s focus on revising 40 CFR 51.307 wording to only change 

what is needed to maintain consistency with revisions to other sections. Due to practical 

experience with visibility notification and consultation between permit authorities and the 

federal land management agencies (FLMs), reviewer thinks this would be a missed 

opportunity if the reviewer did not clarify two related issues: 

1.) that significant visibility impacts can result from anthropogenic emissions 

transported hundreds of kilometers (beyond 100km); and 

2.) that meaningful consultation with the FLMs must include specific, complete, and 

timely information. The reviewer believes this added clarity as relevant to the 

revisions of other sections of this Regional Haze Rule. 

As further described in the Preamble, §51.307 clarified that nonattainment area sources 

are subject to the visibility protection provisions, despite not being subject to the PSD 

requirements, thus addressing a potential unintended consequence of the existing 

permitting construct.1 Similarly, the reviewer recommending that the full visibility 

impacts of sources undergoing major modifications are adequately assessed and 

considered in permitting to avoid a state having to revisit the facility during the regional 

haze process. 

Incremental changes to a large stationary source may not cause or contribute to an 

adverse visibility impact when considered in isolation (i.e., when considering the net 

emission increase only), but the overall impact of the entire facility post-modification 

may be significant. It may be impossible to “prevent any future impairment of visibility” 

if the scope of the visibility analysis for a major modification is limited to the net 

emission increase from the modification alone. The reviewer believes this is also an 

unintended consequence of the existing regulatory language and PSD construct. Our 

recommendation that visibility impacts from the entire facility post-modification be 

analyzed and accounted for is analogous to the required NAAQS demonstration, which 

ensures that the modified source as a whole will not contribute to a NAAQS violation. 

The reviewer recommends the term “major modification” be replaced with “modified 

major source,” as indicated below. The reviewer recommends retaining the term “major 

modification” in paragraph (a) and (a)(1) to specify that it is a major modification that 

triggers PSD/NSR applicability. 

Lastly, the reviewer recommends additions regarding the FLM notification requirement 

to correct a long-standing, again unintended, problem. While FLMs receive from most 

states the draft permit and staff analysis well in advance of the beginning of their public 

review process, some states maintain that our review clock starts when we receive an 
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application, regardless of whether it is complete, is ultimately revised, or it ever proceeds 

to public comment. This has resulted in a lot of wasted effort and uncertainty. 

EPA’s response: No edit has been made in response to this comment. 

Specific Comments: 

1) Page 13 – Reviewer recommends revising the following as provided below and to use the 

standard language “Class I national parks and wilderness areas” as national forests are 

not Class I areas: 

a. 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, national 

forests and other Class I areas due to their “great scenic importance.” 

EPA’s response: Text has been changed in response to this comment. 

2) Page 16 – Reviewer recommends revising the sentence below to state: 

a. However, in some areas, such as Sawtooth Wilderness area in Idaho, improvements 

from reduced emissions from man-made sources have been overwhelmed by 

uncontrollable impacts from fire wildfire and/or dust events. 

EPA’s response: Text has been changed in response to this comment. 

3) Page 21 – Reviewer recommends revising the sentence below to state: 

a. The Regional Haze Rule also provides an alternative to requiring source-specific 

BART controls; under EPA’s regulations, states have the flexibility to adopt an 

emissions trading program or other alternative program as long as the alternative 

provides greater or equivalent reasonable progress towards improving visibility 

than BART and meets certain other requirements set out in 40 CFR 51.308(e)(2). 

EPA’s response: No edit has been made in response to this comment. The 

preamble accurately describes the requirements of this section of the rule, 

which EPA is not proposing to change. This edit would relax the requirements 

of the rule. 

4) Page 27 – Reviewer recommends revising the term “The CAA has the goal of natural 

conditions” as the CAA does not reference “natural conditions,” but rather 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.” 

Natural conditions are a logical offshoot of this statement in the CAA, but are manifest in 

the Regional Haze Rule, not the CAA. 

EPA’s response: Footnote 17 has been added to page 28 in response to this 

comment. 

5) Page 29 – Reviewer recommends revising the part of the sentence below to state 

(footnotes included as additions): 

a. At a minimum, states must describe how each of the following seven factors are 

taken into account in developing their long-term strategy: [. . .] (5) smoke 

management techniques, including the use of Basic Smoke Management 
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Practices2 and state smoke management programs for agricultural and forestry

wildland vegetation management purposes including plans as currently exist within 

the state for these purposes3[. . . .] 

EPA’s response: The edits made in response to general comment number 2 are 

responsive to this suggestion also. 

6) Page 37-38 – Reviewer recommends revising the following sentence to state: 

a. We are proposing to revise §51.307 only as needed to maintain consistency with 

revisions to other sections of 40 CFR part 50 subpart P, to remedy some 

unintended consequences of the existing regulations and clarify FLM 

notification requirements.

EPA’s response: No edit has been made in response to this comment. 

7) Page 43, footnote 22 – Reviewer recommends clarifying the sentence or the footnote as 

the footnote references IMPROVE data from 2000 – 2005 but is referring to the URP 

baseline which is 2000 – 2004. 

EPA’s response: The footnote was in error, and we have made an edit to correct the 

mistake.

8) Page 49 – Reviewer recommends providing additional clarity on how the second 

alternative approach that EPA is seeking comment on differs from the proposed 

approach. As written, there does not appear to be a difference in approaches. 

EPA’s response: We are proposing to either require states to select the most 

impaired days based on anthropogenic impairment OR to allow states to choose 

between selecting the most impaired days based on anthropogenic impairment or 

continue to use total haze. We have added a summary paragraph to page 52 of the 

NPRM to clarify the two approaches. 

9) Page 50 – Reviewer recommends explaining the criteria that would be used to evaluate 

the proposed state methods [for selecting the 20 percent most impaired days] 

understanding that further guidance will provide additional information. 

EPA’s response: No change has been made in response to this comment. 

10) Page 51 – Reviewer recommends clarifying whether effects from China would be 

considered within this rulemaking. 

EPA’s response: Edit has been made on pages 54-55 in response to this comment. 

11) Page 53, footnote 24 – Reviewer recommends removing the concept of adjusting the data 

because adjusting data could corrupt the integrity of the long term monitoring. 

EPA’s response: We have edited the footnote (which now is numbered as footnote 

27 on page 57) to remove any implication of “adjusting” the actual IMPROVE data. 

 

2

 USDA Forest Service and Natural Resources Conservation Service, Basic Smoke Management Practices Tech

Note, October 2011/ http://www.nrcs.usda.gov/Internet/FSE_DOCUMENTS/stelprdb1046311.pdf 

3

 Consistent with recent and ongoing rulemaking by EPA for ozone and exceptional events, it is not the intent of 

EPA to preclude prescribed fire as a wildland vegetation management tool. The EPA understands the importance of 

prescribed fire which mimics a natural process necessary to manage and maintain fire-adapted ecosystems and 

climate change adaptation, while reducing risk of uncontrolled emissions from catastrophic wildfires, and is 

committed to working with all land managers (federal land managers, tribes, states and private) to effectively utilize 

prescribed fire to reduce the impact of catastrophic wildfire related emissions including particulate matter and 

contribution of precursors to ozone. 
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The footnote now is phrased in terms of using IMPROVE data to estimate “current 

conditions” in a way that removes international anthropogenic impacts. 

12) Page 57 – Reviewer recommends providing additional clarification what “significant 

changes” means within § 51.308(g)(5). 

EPA’s response: No edit has been made in response to this comment. The current 

rule uses the term “significant changes” and the proposed rule does not change this. 

13) Page 57 – Reviewer recommends removing the following sentence: 

a. The EPA was encouraged in pre-proposal consultations with FLMs to add this 

requirement. 

EPA’s response: Sentence has been removed in response to this comment. 

14) Page 66 – Reviewer recommends proposing that all RAVI certifications be resolved 

within a 3 year time period as RAVI certification is considered a last resort by FLM 

agencies and is not taken lightly. 

EPA’s response: Text has been added on page 84 in response to this comment. 

15) Page 71 – Reviewer recommends adding the following sentence at the end of the first full 

paragraph before section H. 

a. We are also proposing changing “major modification” to “modified major source” to 

better implement the intent of the CAA with respect to the connection between 

Regional Haze and PSD. Lastly, we are clarifying the FLM notification 

requirements. 

EPA’s response: No edit has been made in response to this comment. 

16) Page 75 – Reviewer recommends that if progress reports are not required to be SIP 

revisions, that EPA still be required to take action either to approve or disapprove the 

mid-term report in response to public comments. 

EPA’s response: No edit has been made in response to this comment. 

17) Page 76 – Reviewer recommends revising the paragraph stating with “The EPA wishes to 

make clear that after considering comments” to specifically solicit comment on the 

section and to remove the negative connotation surrounding the paragraph. 

EPA’s response: Text has been edited on pages 94-95 in response to this comment. 

18) Page 77-78 – Reviewer recommends clarifying what the 1 year deadline is from for 

revising a SIP to address the plan’s deficiencies. 

EPA’s response: Text has been edited on page 95 in response to this comment. 

19) Page 77 – Reviewer recommends that EPA formally sign progress reports to allow the 

State, FLM’s, and the general public, the appropriate opportunity to review and respond 

to EPA’s position. 

EPA’s response: No edit has been made in response to this comment. 

20) Page 80 – Reviewer recommends discussing the deltas numerically from the previously 

approved ICR to show the difference in number of respondents, burden and cost, where 

applicable. 

EPA’s response: Text has been added on pages 98-99 in response to this comment. 

21) Page 88, § 51.301 – Reviewer recommends revising the language to state: 

a. Haze Index Deciview index means a value, expressed in deciview (dv), for a day 

that is derived from calculated or measured light extinction, such that uniform 
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increments of the index correspond to uniform incremental changes in perception 

across the entire range of conditions, from pristine to very obscured. The deciview 

haze index is calculated based on the following equation (for the purposes of 

calculating deciview haze index using IMPROVE data, the atmospheric light 

extinction coefficient must be calculated from aerosol measurements and an 

estimate of Rayleigh scattering): 

Deciview Haze index (dv) =10 lne (bext/10 Mm−1). 

EPA’s Response: This definition has been edited in section 51.301.

22) Page 89, § 51.301, Least impaired days – Reviewer recommends The definition of “least 

impaired days” as stated pertains to the original interpretation that the lowest amounts of 

visibility impairment occurs on the clearest days. That definition needs to state that this 

is a legacy term pertaining to the first planning period and does not apply to the revised 

tracking metric using impairment. For the second planning period and beyond, this term 

should be replaced with “clearest days.” 

EPA’s Response: Edits made in response to general comment 21 also address this 

comment. 

23) Page 90, § 51.301, Visibility – Reviewer recommends revising the language to state the 

following: 

a. Visibility means the degree of perceived clarity when viewing objects at a distance. 

Visibility depends on light extinction, visual range includes perceived changes in

contrast, or coloration, and texture of elements in a scene. 

EPA’s Response: This edit to the rule text has been made. 

24) Page 90, § 51.301 – Reviewer recommends adding the following definition: 

a. Wildland fire means Wildland fire means, for the purposes of this rule, an event and 

its resulting emissions, which may recur, that originates form wildfire or prescribed 

fire, meeting specific requirements as to contribute to the natural visibility condition. 

EPA’s Response: The edits made in response to general comment number 2 

address this comment also. 

25) Page 94, § 51.307, New source review. – Reviewer recommends making the following 

modifications to the following section: 

a. (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)(1)(D) or (E) of the CAA, the State plan must, in 

any review under § 51.166 with respect to visibility protection and analyses, provide 

for: 

(1) Written notification of all affected Federal Land Managers of any proposed new 

major stationary source or major modification that may affect visibility in any 

Federal Class I area. Such notification must be made in writing and include a copy of 

all information relevant to the permit application (including the complete 

application, staff analysis, and draft permit) within 30 days of receipt. The State 

must also provide notification to all affected Federal Land Managers at least 30 days 

prior to publishing the notice of public comment and at least 60 days prior to public 
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hearing by the State (or at least 30 days prior to the public notice if there is no public 

hearing) on the application for permit to construct. Such notification must include 

the public notice, draft permit, staff analysis, complete application, and an analysis 

conducted by the State or applicant of the anticipated impacts from the source on 

visibility in any Federal Class I area . . . . 

(3) Consideration of any analysis performed by the Federal Land Manager, provided 

within 30 days of the notification and analysis required by paragraph (a)(1) of this 

section, that such proposed new major stationary source or major modification 

modified major source may have an adverse impact on visibility in any Federal Class 

I area. Where the State finds that such an analysis does not demonstrate to the 

satisfaction of the State that an adverse impact will result in the Federal Class I area, 

the State must, in the notice of public hearing, either explain its decision or give 

notice as to where the explanation can be obtained.

(b) The plan shall also provide for the review of any new major stationary source or 

major modification modified major source . . . . 

(c) Review of any major stationary source or major modification modified major 

source under paragraph (b) of this section, shall be conducted in accordance with 

paragraph (a) of this section, and § 51.166(o), (p)(1) through (2), and (q). In 

conducting such reviews the State must ensure that the source’s emissions will be 

consistent with making reasonable progress toward the national visibility goal 

referred to in § 51.300(a). The State may take into account the costs of compliance, 

the time necessary for compliance, the energy and nonair quality environmental 

impacts of compliance, and the useful life of the source. 

(d) The State may require monitoring of visibility in any Federal Class I area near 

the proposed new stationary source or major modification modified major source for 

such purposes and by such means as the State deems necessary and appropriate. 

EPA’s response: No edits have been made in response to these comments. 

26) Page 98, § 51.308(f)(1)(i) – While the first sentence is generally true, there were some 

monitoring sites that did not have complete data for that time period so they were 

adjusted to extend beyond that time frame. Therefore, reviewer recommends EPA clarify 

this in the rule or guidance. 

EPA’s response: An edit has been made to this subsection of the rule, along with 

explanatory text on pages 44-45 of the NPRM.

27) Page 99, § 51.308(f)(2)(iii)(A) – Reviewer recommends clarifying how “reasonably 

anticipated” emissions are determined and by whom. 

EPA’s response: No edit has been made in response to this comment. 

28) Page 101, § 51.308(f)(2)(iii)(C) – Reviewer recommends adding the following sentence 

at the end of the (C): 

a. All substantive interstate consultations must be documented. 

EPA’s response: Edit has been made to this subsection, and explanatory text added 

to page 42 of the NPRM, in response to this comment. 
Summary of Interagency Working Comments With EPA Responses on Draft 

Language under EO12866/13563 Interagency Review. Subject to Further 

Policy Review.

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29) Page 101, §51.308(f)(2)(vi)(E) – Reviewer recommends revising the sentence as follows: 

a. Smoke management techniques for agricultural and forestry management purposes 

including basic smoked management practices or State smoke management 

programs plans as currently exist within the State for these purposes; 

EPA’s Response: The edits made in response to general comment number 2 

address this comment also. 

30) Page 102, § 51.308(f)(3)(ii)(A) – Reviewer recommends EPA more specifically state the 

analytical obligations when a state’s reasonable progress goal for the 20 percent most 

impaired days is not on or below the URP line. 

EPA’s response: No edit has been made in response to this comment. This will be 

addressed in the guidance. 

31) Page 102, §51.308(f)(3)(ii)(A) – Reviewer recommends adding the sentence below 

between the sentence ending in “would be reasonable to include in the long-term 

strategy” and the sentence beginning “The State must provide to the public”: 

a. The State must provide a robust demonstration, including documenting the criteria 

used to determine which sources or groups or [sic] 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. 

EPA’s response: The suggested text has been added to this subsection verbatim 

(with the exception of changing the second “or” to “of”), and explanatory text 

has been added to page 42, in response to this comment. 

32) Page 103, § 51.308(f)(3)(ii)(B) – Reviewer recommends clarifying what “same 

demonstration” means with respect to a State must make with respect to its long-term 

strategy. 

EPA’s response: Edit has been made to this subsection in response to this comment. 

33) Page 109, § 51.308(h)(1) – Reviewer recommends revising the sentence as follows: 

a. 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 negative declaration that revision of the existing implementation plan is not needed 

at this time. 

EPA’s response: Edit has been made to this subsection of the rule text in 

response to this comment. A short mention of this rule text edit has been added 

to the preamble on page 75. 

34) Page 109, § 51.308(i)(2) – Reviewer recommends revising the section as follows: 

a. 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 planning the development of its longterm strategy so that information and recommendations provided by the Federal 

Land Manager can meaningfully inform the State’s development of the long-term 

strategy and at least 60 120 days prior to holding any public hearing or other public 

comment opportunity on an implementation plan (or plan revision) or progress 
Summary of Interagency Working Comments With EPA Responses on Draft 

Language under EO12866/13563 Interagency Review. Subject to Further 

Policy Review.

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report for regional haze required by this subpart. This consultation must include the 

opportunity for the affected Federal Land Managers to discuss their: 

EPA’s Response: An edit has been made to 51.308(i)(2) in response to this 

suggestion.. The preamble has also been edited on page 89.

Typographical Comments: 

 

1) Page 42, footnote – Reviewer recommends that it should read “2000-2004”. 

EPA’s response: This footnote (now numbered 24 and appearing on page 44) has 

been edited in response to this comment. 

2) Page 48 – Reviewer recommends using “haze index” as the scale and “deciview” as the 

units for the haze index. “Haze” includes natural light extinction and impairments. 

Impairment, total haze, and natural visibility can all be measured in deciview. 

EPA’s Response: See response to specific comment #21.

3) Page 52 – Reviewer recommends changing “if accrurate” to “if accurate” 

EPA’s response: Text on page 55 has been edited in response to this comment. 

4) Page 81 – Reviewer recommends modifying “oria_submissions@omb.eop.gov” to 

“oira_submissions@omb.eop.gov”. 

EPA’s response: Text on page 99 has been edited in response to this comment. 

5) Page 87, deciview equation – Reviewer recommends changing from “lne” to “ln” is 

natural logarithm, or “loge”. 

EPA’s response: 51.301 (definitions) section has been edited in response to this 

comment. 

6) Page 88 – Reviewer recommends changing “Visibility depends on light extinction, visual 

range, contrast, or coloration.” to “Visibility includes perceived changes in contrast, 

coloration, and texture of elements in a scene.” 

EPA’s Response: This edit has been made.