11858 Federal Register / Vol. 77, No. 39 / Tuesday, February 28, 2012 / Proposed Rules 

G. Executive Order 13045, Protection of 

Children From Environmental Health 

Risks and Safety Risks 

The EPA interprets Executive Order 

13045 (62 FR 19885, April 23, 1997) as 

applying only to those regulatory 

actions that concern health or safety 

risks, such that the analysis required 

under section 5–501 of the Executive 

Order has the potential to influence the 

regulation. This proposed action is not 

subject to Executive Order 13045 

because it is not an economically 

significant regulatory action based on 

health or safety risks subject to 

Executive Order 13045 (62 FR 19885, 

April 23, 1997). This proposed action 

under section 110 and subchapter I, part 

D of the CAA will not in and of itself 

create any new regulations but simply 

approves or disapproves certain State 

requirements for inclusion into the SIP. 

H. Executive Order 13211, Actions That 

Significantly Affect Energy Supply, 

Distribution or Use 

This proposed action is not subject to 

Executive Order 13211 (66 FR 28355, 

May 22, 2001) because it is not a 

significant regulatory action under 

Executive Order 12866. 

I. National Technology Transfer and 

Advancement Act 

Section 12(d) of the National 

Technology Transfer and Advancement 

Act of 1995 (‘‘NTTAA’’), Public Law 

104–113, section 12(d) (15 U.S.C. 272 

note) directs the EPA to use voluntary 

consensus standards in its regulatory 

activities unless to do so would be 

inconsistent with applicable law or 

otherwise impractical. Voluntary 

consensus standards are technical 

standards (e.g., materials specifications, 

test methods, sampling procedures, and 

business practices) that are developed or 

adopted by voluntary consensus 

standards bodies. The NTTAA directs 

the EPA to provide Congress, through 

OMB, explanations when the Agency 

decides not to use available and 

applicable voluntary consensus 

standards. 

The EPA believes that this proposed 

action is not subject to requirements of 

Section 12(d) of the NTTAA because 

application of those requirements would 

be inconsistent with the CAA. 

J. Executive Order 12898: Federal 

Actions To Address Environmental 

Justice in Minority Populations and 

Low-Income Populations 

Executive Order 12898 (59 FR 7629, 

February 16, 1994) establishes federal 

executive policy on environmental 

justice. Its main provision directs 

federal agencies, to the greatest extent 

practicable and permitted by law, to 

make environmental justice part of their 

mission by identifying and addressing, 

as appropriate, disproportionately high 

and adverse human health or 

environmental effects of their programs, 

policies, and activities on minority 

populations and low-income 

populations in the United States. 

The EPA lacks the discretionary 

authority to address environmental 

justice in this proposed action. In 

reviewing SIP submissions, the EPA’s 

role is to approve or disapprove state 

choices, based on the criteria of the 

CAA. Accordingly, this action merely 

proposes to approve or disapprove 

certain State requirements for inclusion 

into the SIP under section 110 and 

subchapter I, part D of the CAA and will 

not in and of itself create any new 

requirements. Accordingly, it does not 

provide the EPA with the discretionary 

authority to address, as appropriate, 

disproportionate human health or 

environmental effects, using practicable 

and legally permissible methods, under 

Executive Order 12898. 

List of Subjects in 40 CFR Part 52 

Environmental protection, Air 

pollution control, Intergovernmental 

relations, Nitrogen dioxide, Ozone, 

Particulate matter, Reporting and 

recordkeeping requirements, Sulfur 

dioxides, Visibility, Interstate transport 

of pollution, Regional haze, Best 

available control technology. 

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

Dated: February 15, 2012. 

Al Armendariz, 

Regional Administrator, Region 6. 

[FR Doc. 2012–4676 Filed 2–27–12; 8:45 am] 

BILLING CODE 6560–50–P 

ENVIRONMENTAL PROTECTION 

AGENCY 

40 CFR Part 52 

[EPA–R04–OAR–2010–0219–201148; FRL– 

9639–2] 

Approval and Promulgation of Air 

Quality Implementation Plans; State of 

North Carolina; Regional Haze State 

Implementation Plan 

AGENCY: Environmental Protection 

Agency (EPA). 

ACTION: Proposed rule. 

SUMMARY: EPA is proposing a limited 

approval of a revision to the North 

Carolina state implementation plan 

(SIP) submitted by the State of North 

Carolina through the North Carolina 

Department of Environment and Natural 

Resources, Division of Air Quality 

(NCDAQ), on December 17, 2007, that 

addresses regional haze for the first 

implementation period. This revision 

addresses the requirements of the Clean 

Air Act (CAA) and EPA’s rules that 

require states to prevent any future and 

remedy any existing anthropogenic 

impairment of visibility in mandatory 

Class I areas (national parks and 

wilderness areas) caused by emissions 

of air pollutants from numerous sources 

located over a wide geographic area 

(also referred to as the ‘‘regional haze 

program’’). States are required to assure 

reasonable progress toward the national 

goal of achieving natural visibility 

conditions in Class I areas. EPA is 

proposing a limited approval of this SIP 

revision to implement the regional haze 

requirements for North Carolina on the 

basis that the revision, as a whole, 

strengthens the North Carolina SIP. In a 

separate action, EPA has proposed a 

limited disapproval of the North 

Carolina regional haze SIP because of 

deficiencies in the State’s regional haze 

SIP submittal arising from the remand 

by the U.S. Court of Appeals for the 

District of Columbia Circuit (DC Circuit) 

to EPA of the Clean Air Interstate Rule 

(CAIR). Consequently, EPA is not 

proposing to take action in this 

rulemaking to address the State’s 

reliance on CAIR to meet certain 

regional haze requirements. 

DATES: Comments must be received on 

or before March 29, 2012. 

ADDRESSES: Submit your comments, 

identified by Docket ID No. EPA–R04– 

OAR–2010–0219, by one of the 

following methods: 

1. www.regulations.gov: Follow the 

on-line instructions for submitting 

comments. 

2. Email: benjamin.lynorae@epa.gov. 

3. Fax: 404–562–9019. 

4. Mail: EPA–R04–OAR–2010–0219, 

Regulatory Development Section, Air 

Planning Branch, Air, Pesticides and 

Toxics Management Division, U.S. 

Environmental Protection Agency, 

Region 4, 61 Forsyth Street SW., 

Atlanta, Georgia 30303–8960. 

5. Hand Delivery or Courier: Lynorae 

Benjamin, Chief, Regulatory 

Development Section, Air Planning 

Branch, Air, Pesticides and Toxics 

Management Division, U.S. 

Environmental Protection Agency, 

Region 4, 61 Forsyth Street SW., 

Atlanta, Georgia 30303–8960. Such 

deliveries are only accepted during the 

Regional Office’s normal hours of 

operation. The Regional Office’s official 

hours of business are Monday through 

Friday, 8:30 to 4:30, excluding federal 

holidays. 

mstockstill on DSK4VPTVN1PROD with PROPOSALS

Federal Register / Vol. 77, No. 39 / Tuesday, February 28, 2012 / Proposed Rules 11859 

1EPA’s TSD to this action, entitled ‘‘Technical 

Support Document for North Carolina Regional 

Haze SIP Submittal,’’ is included in the public 

docket for this action. 

2Under CAA sections 301(a) and 110(k)(6) and 

EPA’s long-standing guidance, a limited approval 

results in approval of the entire SIP submittal, even 

of those parts that are deficient and prevent EPA 

from granting a full approval of the SIP revision. 

Processing of State Implementation Plan (SIP) 

Revisions, EPA Memorandum from John Calcagni, 

Director, Air Quality Management Division, 

OAQPS, to Air Division Directors, EPA Regional 

Offices I–X, September 7, 1992, (1992 Calcagni 

Memorandum) located at: http://www.epa.gov/ttn/ 

caaa/t1/memoranda/siproc.pdf. 

Instructions: Direct your comments to 

Docket ID No. ‘‘EPA–R04–OAR–2010– 

0219.’’ EPA’s policy is that all 

comments received will be included in 

the public docket without change and 

may be made available online at 

www.regulations.gov, including any 

personal information provided, unless 

the comment includes information 

claimed to be Confidential Business 

Information (CBI) or other information 

whose disclosure is restricted by statute. 

Do not submit through 

www.regulations.gov or email, 

information that you consider to be CBI 

or otherwise protected. The 

www.regulations.gov Web site is an 

‘‘anonymous access’’ system, which 

means EPA will not know your identity 

or contact information unless you 

provide it in the body of your comment. 

If you send an email comment directly 

to EPA without going through 

www.regulations.gov, your email 

address will be automatically captured 

and included as part of the comment 

that is placed in the public docket and 

made available on the Internet. If you 

submit an electronic comment, EPA 

recommends that you include your 

name and other contact information in 

the body of your comment and with any 

disk or CD–ROM you submit. If EPA 

cannot read your comment due to 

technical difficulties and cannot contact 

you for clarification, EPA may not be 

able to consider your comment. 

Electronic files should avoid the use of 

special characters, any form of 

encryption, and be free of any defects or 

viruses. For additional information 

about EPA’s public docket visit the EPA 

Docket Center homepage at http:// 

www.epa.gov/epahome/dockets.htm. 

Docket: All documents in the 

electronic docket are listed in the 

www.regulations.gov index. Although 

listed in the index, some information is 

not publicly available, i.e., CBI or other 

information whose disclosure is 

restricted by statute. Certain other 

material, such as copyrighted material, 

is not placed on the Internet and will be 

publicly available only in hard copy 

form. Publicly available docket 

materials are available either 

electronically in www.regulations.gov or 

in hard copy at the Regulatory 

Development Section, Air Planning 

Branch, Air, Pesticides and Toxics 

Management Division, U.S. 

Environmental Protection Agency, 

Region 4, 61 Forsyth Street SW., 

Atlanta, Georgia 30303–8960. EPA 

requests that if at all possible, you 

contact the person listed in the FOR

FURTHER INFORMATION CONTACT section to 

schedule your inspection. The Regional 

Office’s official hours of business are 

Monday through Friday, 8:30 to 4:30, 

excluding federal holidays. 

FOR FURTHER INFORMATION CONTACT: Sara 

Waterson or Michele Notarianni, 

Regulatory Development Section, Air 

Planning Branch, Air, Pesticides and 

Toxics Management Division, U.S. 

Environmental Protection Agency, 

Region 4, 61 Forsyth Street SW., 

Atlanta, Georgia 30303–8960. Sara 

Waterson can be reached at telephone 

number (404) 562–9061 and by 

electronic mail at 

waterson.sara@epa.gov. Michele 

Notarianni can be reached at telephone 

number (404) 562–9031 and by 

electronic mail at 

notarianni.michele@epa.gov. 

SUPPLEMENTARY INFORMATION: 

Table of Contents 

I. What action is EPA proposing? 

II. What is the background for EPA’s 

proposed action? 

A. The Regional Haze Problem 

B. Requirements of the CAA and EPA’s 

Regional Haze Rule (RHR) 

C. Roles of Agencies in Addressing 

Regional Haze 

III. What are the requirements for the regional 

haze SIPs? 

A. The CAA and the RHR 

B. Determination of Baseline, Natural, and 

Current Visibility Conditions 

C. Determination of Reasonable Progress 

Goals (RPGs) 

D. Best Available Retrofit Technology 

(BART) 

E. Long-Term Strategy (LTS) 

F. Coordinating Regional Haze and 

Reasonably Attributable Visibility 

Impairment (RAVI) LTS 

G. Monitoring Strategy and Other 

Implementation Plan Requirements 

H. Consultation With States and Federal 

Land Managers (FLMs) 

IV. What is EPA’s analysis of North 

Carolina’s regional haze submittal? 

A. Affected Class I Areas 

B. Determination of Baseline, Natural, and 

Current Visibility Conditions 

1. Estimating Natural Visibility Conditions 

2. Estimating Baseline Conditions 

3. Summary of Baseline and Natural 

Conditions 

4. Uniform Rate of Progress 

C. Long-Term Strategy/Strategies 

1. Emissions Inventory for 2018 With 

Federal and State Control Requirements 

2. Modeling To Support the LTS and 

Determine Visibility Improvement for 

Uniform Rate of Progress 

3. Relative Contributions to Visibility 

Impairment: Pollutants, Source 

Categories, and Geographic Areas 

4. Procedure for Identifying Sources To 

Evaluate for Reasonable Progress 

Controls in North Carolina and 

Surrounding Areas 

5. Application of the Four CAA Factors in 

the Reasonable Progress Analysis 

6. BART 

7. RPGs 

D. Coordination of RAVI and Regional 

Haze Requirements 

E. Monitoring Strategy and Other 

Implementation Plan Requirements 

F. Consultation With States and FLMs 

1. Consultation With Other States 

2. Consultation With the FLMs 

G. Periodic SIP Revisions and Five-Year 

Progress Reports 

V. What action is EPA proposing? 

VI. Statutory and Executive Order Reviews 

I. What action is EPA proposing? 

EPA is proposing a limited approval 

of North Carolina’s December 17, 2007, 

SIP revision addressing regional haze 

under CAA sections 301(a) and 

110(k)(3) because the revision as a 

whole strengthens the North Carolina 

SIP. This proposed rulemaking and the 

accompanying Technical Support 

Document 1 (TSD) explain the basis for 

EPA’s proposed limited approval 

action.2

In a separate action, EPA has 

proposed a limited disapproval of the 

North Carolina regional haze SIP 

because of deficiencies in the State’s 

regional haze SIP submittal arising from 

the State’s reliance on CAIR to meet 

certain regional haze requirements. See 

76 FR 82219 (December 30, 2011). EPA 

is not proposing to take action in today’s 

rulemaking on issues associated with 

North Carolina’s reliance on CAIR in its 

regional haze SIP. Comments on EPA’s 

proposed limited disapproval of North 

Carolina’s regional haze SIP are 

accepted at the docket for EPA’s 

December 30, 2011, proposed 

rulemaking (see Docket ID No. EPA– 

HQ–OAR–2011–0729). The comment 

period for EPA’s December 30, 2011, 

proposed rulemaking is scheduled to 

end on February 28, 2012. 

II. What is the background for EPA’s 

proposed action? 

A. The Regional Haze Problem 

Regional haze is visibility impairment 

that is produced by a multitude of 

sources and activities which are located 

across a broad geographic area and emit 

fine particles (PM2.5) (e.g., sulfates, 

mstockstill on DSK4VPTVN1PROD with PROPOSALS

11860 Federal Register / Vol. 77, No. 39 / Tuesday, February 28, 2012 / Proposed Rules 

3 Visual range is the greatest distance, in 

kilometers or miles, at which a dark object can be 

viewed against the sky. 4Areas 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. See 42 

U.S.C. 7472(a). In accordance with section 169A of 

the CAA, EPA, in consultation with the Department 

of Interior, promulgated a list of 156 areas where 

visibility is identified as an important value. See 44 

FR 69122 (November 30, 1979). The extent of a 

mandatory Class I area includes subsequent changes 

in boundaries, such as park expansions. See 42 

U.S.C. 7472(a). Although states and tribes may 

designate as Class I additional areas which they 

consider to have visibility as an important value, 

the requirements of the visibility program set forth 

in section 169A of the CAA apply only to 

‘‘mandatory Class I Federal areas.’’ Each mandatory 

Class I Federal area is the responsibility of a 

‘‘Federal Land Manager.’’ See 42 U.S.C. 7602(i). 

When the term ‘‘Class I area’’ is used in this action, 

it means a ‘‘mandatory Class I Federal area.’’ 

5Albuquerque/Bernalillo County in New Mexico 

must also submit a regional haze SIP to completely 

satisfy the requirements of section 110(a)(2)(D) of 

the CAA for the entire State of New Mexico under 

the New Mexico Air Quality Control Act (section 

74–2–4). 

nitrates, organic carbon, elemental 

carbon, and soil dust), and their 

precursors (e.g., sulfur dioxide (SO2), 

nitrogen oxides (NOX), and in some 

cases, ammonia (NH3) and volatile 

organic compounds (VOC)). Fine 

particle precursors react in the 

atmosphere to form fine particulate 

matter which impairs visibility by 

scattering and absorbing light. Visibility 

impairment reduces the clarity, color, 

and visible distance that one can see. 

PM2.5 can also cause serious health 

effects and mortality in humans and 

contributes 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 visibility 

impairment caused by air pollution 

occurs virtually all the time at most 

national park and wilderness areas. The 

average visual range 3 in many Class I 

areas 4 (i.e., national parks and memorial 

parks, wilderness areas, and 

international parks meeting certain size 

criteria) in the western United States is 

100–150 kilometers, or about one-half to 

two-thirds of the visual range that 

would exist without anthropogenic air 

pollution. In most of the eastern Class 

I areas of the United States, the average 

visual range is less than 30 kilometers, 

or about one-fifth of the visual range 

that would exist under estimated 

natural conditions. See 64 FR 35715 

(July 1, 1999). 

B. Requirements of the CAA and EPA’s 

Regional Haze Rule (RHR) 

In section 169A of the 1977 

Amendments to the CAA, Congress 

created a program for protecting 

visibility in the nation’s national parks 

and wilderness areas. This section of the 

CAA establishes as a national goal the 

‘‘prevention of any future, and the 

remedying of any existing, impairment 

of visibility in mandatory Class I areas 

which impairment results from 

manmade air pollution.’’ On December 

2, 1980, EPA promulgated regulations to 

address visibility impairment in Class I 

areas that is ‘‘reasonably attributable’’ to 

a single source or small group of 

sources, i.e., ‘‘reasonably attributable 

visibility impairment.’’ See 45 FR 

80084. These regulations represented 

the first phase in addressing visibility 

impairment. EPA deferred action on 

regional haze that emanates from a 

variety of sources until monitoring, 

modeling and scientific knowledge 

about the relationships between 

pollutants and visibility impairment 

were improved. 

Congress added section 169B to the 

CAA in 1990 to address regional haze 

issues. EPA promulgated a rule to 

address regional haze on July 1, 1999 

(64 FR 35713), the RHR. The RHR 

revised the existing visibility 

regulations to integrate into the 

regulation provisions addressing 

regional haze impairment and 

established a comprehensive visibility 

protection program for Class I areas. The 

requirements for regional haze, found at 

40 CFR 51.308 and 51.309, are included 

in EPA’s visibility protection 

regulations at 40 CFR 51.300–309. Some 

of the main elements of the regional 

haze requirements are summarized in 

section III of this preamble. The 

requirement to submit a regional haze 

SIP applies to all 50 states, the District 

of Columbia, and the Virgin Islands.5 40 

CFR 51.308(b) requires states to submit 

the first implementation plan 

addressing regional haze visibility 

impairment no later than December 17, 

2007. 

C. Roles of Agencies in Addressing 

Regional Haze 

Successful implementation of the 

regional haze program will require longterm regional coordination among 

states, tribal governments and various 

federal agencies. As noted above, 

pollution affecting the air quality in 

Class I areas can be transported over 

long distances, even hundreds of 

kilometers. 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, 

EPA has encouraged the states and 

tribes across the United States to 

address visibility impairment from a 

regional perspective. Five regional 

planning organizations (RPOs) were 

developed 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 pursued the development of 

regional strategies to reduce emissions 

of particulate matter (PM) and other 

pollutants leading to regional haze. 

The Visibility Improvement State and 

Tribal Association of the Southeast 

(VISTAS) RPO is a collaborative effort of 

state governments, tribal governments, 

and various federal agencies established 

to initiate and coordinate activities 

associated with the management of 

regional haze, visibility and other air 

quality issues in the Southeastern 

United States. Member state and tribal 

governments include: Alabama, Florida, 

Georgia, Kentucky, Mississippi, North 

Carolina, South Carolina, Tennessee, 

Virginia, West Virginia, and the Eastern 

Band of the Cherokee Indians. 

III. What are the requirements for 

regional haze SIPs? 

A. The CAA and the RHR 

Regional haze SIPs must assure 

reasonable progress towards the 

national goal of achieving natural 

visibility conditions in Class I areas. 

Section 169A of the CAA and EPA’s 

implementing regulations require states 

to establish long-term strategies for 

making reasonable progress toward 

meeting this goal. Implementation plans 

must also give specific attention to 

certain stationary sources that were in 

existence on August 7, 1977, but were 

not in operation before August 7, 1962, 

and require these sources, where 

appropriate, to install BART controls for 

the purpose of eliminating or reducing 

visibility impairment. The specific 

regional haze SIP requirements are 

discussed in further detail below. 

B. Determination of Baseline, Natural, 

and Current Visibility Conditions 

The RHR establishes the deciview as 

the principal metric or unit for 

expressing visibility. This visibility 

metric expresses uniform changes in 

haziness in terms of common 

increments across the entire range of 

visibility conditions, from pristine to 

mstockstill on DSK4VPTVN1PROD with PROPOSALS

Federal Register / Vol. 77, No. 39 / Tuesday, February 28, 2012 / Proposed Rules 11861 

6The preamble to the RHR provides additional 

details about the deciview. See 64 FR 35714, 35725 

(July 1, 1999). 

7The set of ‘‘major stationary sources’’ potentially 

subject to BART is listed in CAA section 169A(g)(7). 

extremely hazy conditions. Visibility 

expressed in deciviews is determined by 

using air quality measurements to 

estimate light extinction and then 

transforming the value of light 

extinction using a logarithm function. 

The deciview is a more useful measure 

for tracking progress in improving 

visibility than light extinction itself 

because each deciview change is an 

equal incremental change in visibility 

perceived by the human eye. Most 

people can detect a change in visibility 

at one deciview.6

The deciview is used in expressing 

RPGs (which are interim visibility goals 

towards meeting the national visibility 

goal), defining baseline, current, and 

natural conditions, and tracking changes 

in visibility. The regional haze SIPs 

must contain measures that ensure 

‘‘reasonable progress’’ toward the 

national goal of preventing and 

remedying visibility impairment in 

Class I areas caused by anthropogenic 

air pollution by reducing anthropogenic 

emissions that cause regional haze. The 

national goal is a return to natural 

conditions, i.e., anthropogenic sources 

of air pollution would no longer impair 

visibility in Class I areas. 

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 the 

degree of existing visibility impairment 

at each Class I area at the time of each 

regional haze SIP submittal and 

periodically review progress every five 

years midway through each 10-year 

implementation period. To do this, the 

RHR requires states to determine the 

degree of impairment (in deciviews) for 

the average of the 20 percent least 

impaired (‘‘best’’) and 20 percent most 

impaired (‘‘worst’’) visibility days over 

a specified time period at each of their 

Class I areas. In addition, states must 

also develop an estimate of natural 

visibility conditions for the purpose of 

comparing 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. EPA has provided guidance 

to states regarding how to calculate 

baseline, natural and current visibility 

conditions in documents titled, EPA’s 

Guidance for Estimating Natural 

Visibility conditions under the Regional 

Haze Rule, September 2003, (EPA–454/ 

B–03–005 located at http:// 

www.epa.gov/ttncaaa1/t1/memoranda/ 

rh_envcurhr_gd.pdf), (hereinafter 

referred to as ‘‘EPA’s 2003 Natural 

Visibility Guidance’’), and Guidance for 

Tracking Progress Under the Regional 

Haze Rule, September 2003, (EPA–454/ 

B–03–004 located at http:// 

www.epa.gov/ttncaaa1/t1/memoranda/ 

rh_tpurhr_gd.pdf), (hereinafter referred 

to as ‘‘EPA’s 2003 Tracking Progress 

Guidance’’). 

For the first regional haze SIPs that 

were due by December 17, 2007, 

‘‘baseline visibility conditions’’ were the 

starting points for assessing ‘‘current’’ 

visibility impairment. Baseline visibility 

conditions represent 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 five-year period. The 

comparison of initial baseline visibility 

conditions to natural visibility 

conditions indicates the amount of 

improvement necessary to attain natural 

visibility, while the future comparison 

of baseline conditions to the then 

current conditions will indicate the 

amount of progress made. In general, the 

2000–2004 baseline period is 

considered the time from which 

improvement in visibility is measured. 

C. Determination of Reasonable Progress 

Goals (RPGs) 

The vehicle for ensuring continuing 

progress towards achieving the natural 

visibility goal is the submission of a 

series of regional haze SIPs from the 

states that establish two RPGs (i.e., two 

distinct goals, one for the ‘‘best’’ and 

one for the ‘‘worst’’ days) for every Class 

I area for each (approximately) 10-year 

implementation period. The RHR 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 (i.e., ‘‘background’’) visibility 

conditions. In setting RPGs, states must 

provide for an improvement in visibility 

for the most impaired days over the 

(approximately) 10-year period of the 

SIP, and ensure no degradation in 

visibility for the least impaired days 

over the same period. 

States have significant discretion in 

establishing RPGs, but are required to 

consider the following factors 

established in section 169A of the CAA 

and in EPA’s RHR 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 are 

considered when selecting the RPGs for 

the best and worst days for each 

applicable Class I area. States have 

considerable flexibility in how they take 

these factors into consideration, as 

noted in EPA’s Guidance for Setting 

Reasonable Progress Goals Under the 

Regional Haze Program, (‘‘EPA’s 

Reasonable Progress Guidance’’), July 1, 

2007, memorandum from William L. 

Wehrum, Acting Assistant 

Administrator for Air and Radiation, to 

EPA Regional Administrators, EPA 

Regions 1–10 (pp. 4–2, 5–1). In setting 

the RPGs, states must also consider the 

rate of progress needed to reach natural 

visibility conditions by 2064 (referred to 

as the ‘‘uniform rate of progress’’ or the 

‘‘glidepath’’) and the emissions 

reduction measures needed to achieve 

that rate of progress over the 10-year 

period of the SIP. Uniform progress 

towards achievement of natural 

conditions by the year 2064 represents 

a rate of progress which states are to use 

for analytical comparison to the amount 

of progress they expect to achieve. In 

setting RPGs, each state with one or 

more Class I areas (‘‘Class I state’’) must 

also consult with potentially 

‘‘contributing states,’’ i.e., other nearby 

states with emissions sources that may 

be affecting visibility impairment at the 

Class I state’s areas. See 40 CFR 

51.308(d)(1)(iv). 

D. Best Available Retrofit Technology 

(BART) 

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 contain 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 7 built between 1962 

and 1977 procure, install, and operate 

the ‘‘Best Available Retrofit 

Technology’’ as determined by the state. 

Under the RHR, states are directed to 

conduct BART determinations for such 

‘‘BART-eligible’’ sources that may be 

anticipated to cause or contribute to any 

visibility impairment in a Class I area. 

Rather than requiring source-specific 

mstockstill on DSK4VPTVN1PROD with PROPOSALS

11862 Federal Register / Vol. 77, No. 39 / Tuesday, February 28, 2012 / Proposed Rules 

BART controls, states also have the 

flexibility to adopt an emissions trading 

program or other alternative program as 

long as the alternative provides greater 

reasonable progress towards improving 

visibility than BART. 

On July 6, 2005, 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 emissions limits for each 

applicable source. In making a BART 

determination for a fossil fuel-fired 

electric generating plant with a total 

generating capacity in excess of 750 

megawatts (MW), a state must use the 

approach set forth in the BART 

Guidelines. A state is encouraged, but 

not required, to follow the BART 

Guidelines in making BART 

determinations for other types of 

sources. 

States must address all visibilityimpairing pollutants emitted by a source 

in the BART determination process. The 

most significant visibility impairing 

pollutants are SO2, NOX, and PM. EPA 

has stated that states should use their 

best judgment in determining whether 

VOC or NH3 compounds impair 

visibility in Class I areas. 

Under the BART Guidelines, states 

may select an exemption threshold 

value for their BART modeling, below 

which a BART-eligible source would 

not be expected to cause or contribute 

to visibility impairment in any Class I 

area. The state must document this 

exemption threshold value in the SIP 

and must state the basis for its selection 

of that value. Any source with 

emissions that model above the 

threshold value would be subject to a 

BART determination review. The BART 

Guidelines acknowledge varying 

circumstances affecting different Class I 

areas. States should consider the 

number of emission sources affecting 

the Class I areas at issue and the 

magnitude of the individual sources’ 

impacts. Any exemption threshold set 

by the state should not be higher than 

0.5 deciview. 

In their SIPs, states must identify 

potential BART sources, described as 

‘‘BART-eligible sources’’ in the RHR, 

and document their BART control 

determination analyses. In making 

BART determinations, section 

169A(g)(2) of the CAA requires that 

states consider the following factors: (1) 

The costs of compliance, (2) the energy 

and non-air quality environmental 

impacts of compliance, (3) any existing 

pollution control technology in use at 

the source, (4) the remaining useful life 

of the source, and (5) the degree of 

improvement in visibility which may 

reasonably be anticipated to result from 

the use of such technology. States are 

free to determine the weight and 

significance to be assigned to each 

factor. 

A regional haze SIP must include 

source-specific BART emission limits 

and compliance schedules for each 

source subject to BART. Once a state has 

made its BART determination, the 

BART controls must be installed and in 

operation as expeditiously as 

practicable, but no later than five years 

after the date of EPA approval of the 

regional haze SIP. See CAA section 

169(g)(4); see 40 CFR 51.308(e)(1)(iv). In 

addition to what is required by the RHR, 

general SIP requirements mandate that 

the SIP must also include all regulatory 

requirements related to monitoring, 

recordkeeping, and reporting for the 

BART controls on the source. 

As noted above, the RHR allows states 

to implement an alternative program in 

lieu of BART so long as the alternative 

program can be demonstrated to achieve 

greater reasonable progress toward the 

national visibility goal than would 

BART. Under regulations issued in 2005 

revising the regional haze program, EPA 

made just such a demonstration for 

CAIR. See 70 FR 39104 (July 6, 2005). 

EPA’s regulations provide that states 

participating in the CAIR cap-and trade 

program under 40 CFR part 96 pursuant 

to an EPA-approved CAIR SIP or which 

remain subject to the CAIR Federal 

Implementation Plan in 40 CFR part 97 

need not require affected BART-eligible 

electrical generating (EGUs) to install, 

operate, and maintain BART for 

emissions of SO2 and NOX. See 40 CFR 

51.308(e)(4). Because CAIR did not 

address direct emissions of PM, states 

were still required to conduct a BART 

analysis for PM emissions from EGUs 

subject to BART for that pollutant. 

Challenges to CAIR, however, resulted 

in the remand of the rule to EPA. See 

North Carolina v. EPA, 550F.3d 1175 

(DC Cir. 2008). 

EPA issued a new rule in 2011 to 

address the interstate transport of NOX

and SO2 in the eastern United States. 

See 76 FR 48208 (August 8, 2011) (‘‘the 

Transport Rule,’’ also known as the 

Cross-State Air Pollution Rule). On 

December 30, 2011, EPA proposed to 

find that the trading programs in the 

Transport Rule would achieve greater 

reasonable progress towards the 

national goal than would BART in the 

states in which the Transport Rule 

applies. See 76 FR 82219. Based on this 

proposed finding, EPA also proposed to 

revise the RHR to allow states to 

substitute participation in the trading 

programs under the Transport Rule for 

source-specific BART. EPA has not yet 

taken final action on that rule. Also on 

December 30, 2011, the DC Circuit 

issued an order addressing the status of 

the Transport Rule and CAIR in 

response to motions filed by numerous 

parties seeking a stay of the Transport 

Rule pending judicial review. In that 

order, the DC Circuit stayed the 

Transport Rule pending the court’s 

resolutions of the petitions for review of 

that rule in EME Homer Generation, L.P. 

v. EPA (No. 11–1302 and consolidated 

cases). The court also indicated that 

EPA is expected to continue to 

administer CAIR in the interim until the 

court rules on the petitions for review 

of the Transport Rule. 

E. Long-Term Strategy (LTS) 

Consistent with the requirement in 

section 169A(b) of the CAA that states 

include in their regional haze SIP a 10 

to 15 year strategy for making 

reasonable progress, section 51.308(d)(3) 

of the RHR requires that states include 

a LTS in their regional haze SIPs. The 

LTS is the compilation of all control 

measures a state will use during the 

implementation period of the specific 

SIP submittal to meet applicable RPGs. 

The LTS must include ‘‘enforceable 

emissions limitations, compliance 

schedules, and other measures as 

necessary to achieve the reasonable 

progress goals’’ for all Class I areas 

within, or affected by emissions from, 

the state. See 40 CFR 51.308(d)(3). 

When a state’s emissions are 

reasonably anticipated to cause or 

contribute to visibility impairment in a 

Class I area located in another state, the 

RHR requires the impacted state to 

coordinate with the contributing states 

in order to develop coordinated 

emissions management strategies. See 

40 CFR 51.308(d)(3)(i). In such cases, 

the contributing state must demonstrate 

that it has included, in its SIP, all 

measures necessary to obtain its share of 

the emissions reductions needed to 

meet the RPGs for the Class I area. The 

RPOs have provided forums for 

significant interstate consultation, but 

additional consultations between states 

may be required to sufficiently address 

interstate visibility issues. This is 

especially true where two states belong 

to different RPOs. 

States should consider all types of 

anthropogenic sources of visibility 

impairment in developing their LTS, 

including stationary, minor, mobile, and 

area sources. At a minimum, states must 

describe how each of the following 

seven factors listed below are taken into 

mstockstill on DSK4VPTVN1PROD with PROPOSALS

Federal Register / Vol. 77, No. 39 / Tuesday, February 28, 2012 / Proposed Rules 11863 

account in developing their LTS: (1) 

Emissions reductions due to ongoing air 

pollution control programs, including 

measures to address RAVI; (2) measures 

to mitigate the impacts of construction 

activities; (3) emissions limitations and 

schedules for compliance to achieve the 

RPG; (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 LTS. See 40 CFR 

51.308(d)(3)(v). 

F. Coordinating Regional Haze and 

Reasonably Attributable Visibility 

Impairment (RAVI) LTS 

As part of the RHR, EPA revised 40 

CFR 51.306(c) regarding the LTS for 

RAVI to require that the RAVI plan must 

provide for a periodic review and SIP 

revision not less frequently than every 

three years until the date of submission 

of the state’s first plan addressing 

regional haze visibility impairment, 

which was due December 17, 2007, in 

accordance with 40 CFR 51.308(b) and 

(c). On or before this date, the state must 

revise its plan to provide for review and 

revision of a coordinated LTS for 

addressing RAVI and regional haze, and 

the state must submit the first such 

coordinated LTS with its first regional 

haze SIP. Future coordinated LTS’s, and 

periodic progress reports evaluating 

progress towards RPGs, 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 LTS 

must report on both regional haze and 

RAVI impairment and must be 

submitted to EPA as a SIP revision. 

G. Monitoring Strategy and Other 

Implementation Plan Requirements 

Section 51.308(d)(4) of the RHR 

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 section 51.305 for 

RAVI. Compliance with this 

requirement may be met through 

‘‘participation’’ in the IMPROVE 

network, i.e., review and use of 

monitoring data from the network. The 

monitoring strategy is due with the first 

regional haze SIP, and it must be 

reviewed every five years. The 

monitoring strategy must also provide 

for additional monitoring sites if the 

IMPROVE network is not sufficient to 

determine whether RPGs will be met. 

The SIP must also provide for the 

following: 

• Procedures for using monitoring 

data and other information in a state 

with mandatory Class I areas to 

determine the contribution of emissions 

from within the state to regional haze 

visibility impairment at Class I areas 

both within and outside the state; 

• Procedures for using monitoring 

data and other information in a state 

with no mandatory Class I areas to 

determine the contribution of emissions 

from within the state to regional haze 

visibility impairment at Class I areas in 

other states; 

• Reporting of all visibility 

monitoring data to the Administrator at 

least annually for each Class I area in 

the state, and where possible, in 

electronic format; 

• Developing a statewide inventory of 

emissions of pollutants that are 

reasonably anticipated to cause or 

contribute to visibility impairment in 

any Class I 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. A state 

must also make a commitment to update 

the inventory periodically; and 

• Other elements, including 

reporting, recordkeeping, and other 

measures necessary to assess and report 

on visibility. 

The RHR 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. 

Periodic SIP revisions must meet the 

core requirements of section 51.308(d) 

with the exception of BART. The 

requirement to evaluate sources for 

BART applies only to the first regional 

haze SIP. Facilities subject to BART 

must continue to comply with the BART 

provisions of section 51.308(e), as noted 

above. Periodic SIP revisions will assure 

that the statutory requirement of 

reasonable progress will continue to be 

met. 

H. Consultation With States and Federal 

Land Managers (FLMs) 

The RHR requires that states consult 

with FLMs before adopting and 

submitting their SIPs. See 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 RPGs 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, five-year progress reports, and 

the implementation of other programs 

having the potential to contribute to 

impairment of visibility in Class I areas. 

IV. What is EPA’s analysis of North 

Carolina’s regional haze submittal? 

On December 17, 2007, NCDAQ 

submitted revisions to the North 

Carolina SIP to address regional haze in 

the State’s Class I areas as required by 

EPA’s RHR. 

A. Affected Class I Areas 

North Carolina has five Class I areas 

within its borders: Great Smoky 

Mountains National Park, Joyce KilmerSlickrock Wilderness Area, Linville 

Gorge Wilderness Area, Shining Rock 

Wilderness Area, and Swanquarter 

Wilderness Area. Two of these Class I 

areas (Great Smoky Mountains and 

Joyce Kilmer) also fall within the 

geographic boundaries of Tennessee. 

Therefore, both North Carolina and 

Tennessee are responsible for 

developing their own regional haze SIPs 

that address these two Class I areas and 

for consulting with other states that 

impact the areas. The two states worked 

together to determine appropriate RPGs, 

including consulting with other states 

that impact these two Class I areas, as 

discussed in section IV.F.1 of this 

rulemaking. In addition, both North 

Carolina and Tennessee are responsible 

for describing their own long-term 

emissions strategies, their role in the 

consultation processes, and how their 

particular state SIP meets the other 

requirements in EPA’s regional haze 

regulations. 

The North Carolina regional haze SIP 

establishes RPGs for visibility 

improvement at each of these Class I 

areas and a LTS to achieve those RPGs 

within the first regional haze 

implementation period ending in 2018. 

In developing the LTS for each area, 

North Carolina considered both 

emissions sources inside and outside of 

North Carolina that may cause or 

mstockstill on DSK4VPTVN1PROD with PROPOSALS

11864 Federal Register / Vol. 77, No. 39 / Tuesday, February 28, 2012 / Proposed Rules 

8The IMPROVE program is a cooperative 

measurement effort governed by a steering 

committee composed of representatives from 

federal agencies (including representatives from 

EPA and the FLMs) and RPOs. The IMPROVE 

monitoring program was established in 1985 to aid 

the creation of Federal and State implementation 

plans for the protection of visibility in Class I areas. 

One of the objectives of IMPROVE is to identify 

chemical species and emissions sources responsible 

for existing anthropogenic visibility impairment. 

The IMPROVE program has also been a key 

participant in visibility-related research, including 

the advancement of monitoring instrumentation, 

analysis techniques, visibility modeling, policy 

formulation and source attribution field studies. 

9The science behind the revised IMPROVE 

equation is summarized in numerous published 

papers. See, e.g., Hand, J.L., and Malm, W.C., 2006, 

Review of the IMPROVE Equation for Estimating 

Ambient Light Extinction Coefficients—Final 

Report. March 2006. Prepared for Interagency 

Monitoring of Protected Visual Environments 

(IMPROVE), Colorado State University, Cooperative 

Institute for Research in the Atmosphere, Fort 

Collins, Colorado. http://vista.cira.colostate.edu/ 

improve/publications/GrayLit/ 

016_IMPROVEeqReview/IMPROVEeqReview.htm; 

and Pitchford, Marc., 2006, Natural Haze Levels II: 

Application of the New IMPROVE Algorithm to 

Natural Species Concentrations Estimates. Final 

Report of the Natural Haze Levels II Committee to 

the RPO Monitoring/Data Analysis Workgroup. 

September 2006. http://vista.cira.colostate.edu/ 

improve/Publications/GrayLit/029_NaturalCondII/ 

naturalhazelevelsIIreport.ppt. 

contribute to visibility impairment in 

North Carolina’s Class I areas. The State 

also identified and considered 

emissions sources within North 

Carolina that may cause or contribute to 

visibility impairment in Class I areas in 

neighboring states as required by 40 

CFR 51.308(d)(3). The VISTAS RPO 

worked with the State in developing the 

technical analyses used to make these 

determinations, including state-by-state 

contributions to visibility impairment in 

specific Class I areas, which included 

the five areas in North Carolina and 

those areas affected by emissions from 

North Carolina. 

B. Determination of Baseline, Natural, 

and Current Visibility Conditions 

As required by the RHR and in 

accordance with EPA’s 2003 Natural 

Visibility Guidance, North Carolina 

calculated baseline/current and natural 

visibility conditions for each of its Class 

I areas, as summarized below (and as 

further described in sections III.B.1 and 

III.B.2 of EPA’s TSD to this Federal 

Register action). 

1. Estimating Natural Visibility 

Conditions 

Natural background visibility, as 

defined in EPA’s 2003 Natural Visibility 

Guidance, is estimated by calculating 

the expected light extinction using 

default estimates of natural 

concentrations of fine particle 

components adjusted by site-specific 

estimates of humidity. This calculation 

uses the IMPROVE equation, which is a 

formula for estimating light extinction 

from the estimated natural 

concentrations of fine particle 

components (or from components 

measured by the IMPROVE monitors). 

As documented in EPA’s 2003 Natural 

Visibility Guidance, EPA allows states 

to use ‘‘refined’’ or alternative 

approaches to the 2003 EPA guidance to 

estimate the values that characterize the 

natural visibility conditions of the Class 

I areas. One alternative approach is to 

develop and justify the use of 

alternative estimates of natural 

concentrations of fine particle 

components. Another alternative is to 

use the ‘‘new IMPROVE equation’’ that 

was adopted for use by the IMPROVE 

Steering Committee in December 2005.8

The purpose of this refinement to the 

‘‘old IMPROVE equation’’ is to provide 

more accurate estimates of the various 

factors that affect the calculation of light 

extinction. North Carolina opted to use 

the default estimates for the natural 

concentrations combined with the ‘‘new 

IMPROVE equation’’ for all of its Class 

I areas. Using this approach, natural 

visibility conditions using the new 

IMPROVE equation were calculated 

separately for each Class I area by 

VISTAS. 

The new IMPROVE equation takes 

into account the most recent review of 

the science 9 and it accounts for the 

effect of particle size distribution on 

light extinction efficiency of sulfate, 

nitrate, and organic carbon. It also 

adjusts the mass multiplier for organic 

carbon (particulate organic matter) by 

increasing it from 1.4 to 1.8. New terms 

are added to the equation to account for 

light extinction by sea salt and light 

absorption by gaseous nitrogen dioxide. 

Site-specific values are used for 

Rayleigh scattering (scattering of light 

due to atmospheric gases) to account for 

the site-specific effects of elevation and 

temperature. Separate relative humidity 

enhancement factors are used for small 

and large size distributions of 

ammonium sulfate and ammonium 

nitrate and for sea salt. The terms for the 

remaining contributors, elemental 

carbon (light-absorbing carbon), fine 

soil, and coarse mass terms, do not 

change between the original and new 

IMPROVE equations. 

2. Estimating Baseline Conditions 

NCDAQ estimated baseline visibility 

conditions at the State’s five Class I 

areas using available monitoring data 

from four IMPROVE monitoring sites. 

The Joyce Kilmer-Slickrock Wilderness 

Area does not contain an IMPROVE 

monitor. In cases where onsite 

monitoring is not available, 40 CFR 

51.308(d)(2)(i) requires states to use the 

most representative monitoring 

available for the 2000–2004 period to 

establish baseline visibility conditions, 

in consultation with EPA. North 

Carolina used, and EPA is proposing to 

find adequate North Carolina’s use of, 

2000–2004 data from the IMPROVE 

monitor at Great Smoky Mountains 

National Park for the Joyce KilmerSlickrock Wilderness Area. The 

IMPROVE Steering Committee considers 

the IMPROVE monitor at the Great 

Smoky Mountains to be representative 

of visibility in Joyce Kilmer. The Great 

Smoky Mountains National Park is the 

nearest Class I area and contiguous to 

Joyce Kilmer and they possess similar 

characteristics, such as meteorology and 

topography. 

As explained in section III.B, for the 

first regional haze SIP, baseline 

visibility conditions are the same as 

current conditions. A five-year average 

of the 2000 to 2004 monitoring data was 

calculated for each of the 20 percent 

worst and 20 percent best visibility days 

at each North Carolina Class I area. 

IMPROVE data records for Great Smoky 

Mountains National Park and the 

Linville Gorge Wilderness Area for the 

period 2000 to 2004 meet the EPA 

requirements for data completeness. See 

page 2–8 of EPA’s 2003 Tracking 

Progress Guidance. Shining Rock and 

Swanquarter Class I areas had missing 

data in more than one year between the 

years 2000 to 2004. Data records for 

these sites were filled using data 

substitution procedures. Tables 3.3–1, 

3.3–2, 3.3–3, and 3.3–4 from Appendix 

G of the North Carolina regional haze 

SIP, also provided in section III.B.3 of 

EPA’s TSD to this action, list the 20 

percent best and worst days for the 

baseline period of 2000–2004 for the 

Great Smoky Mountains, Linville Gorge, 

Shining Rock, and Swanquarter areas, 

respectively. These data are also 

provided at the following Web site: 

http://www.metro4-sesarm.org/vistas/ 

SesarmBext_20BW.htm. 

3. Summary of Baseline and Natural 

Conditions 

For the North Carolina Class I areas, 

baseline visibility conditions on the 20 

percent worst days range between 

approximately 24.5 and 30.5 deciviews. 

Natural visibility in these areas is 

predicted to be between approximately 

11 and 12 deciviews on the 20 percent 

worst days. The natural and baseline 

conditions for North Carolina’s Class I 

areas for both the 20 percent worst and 

mstockstill on DSK4VPTVN1PROD with PROPOSALS

Federal Register / Vol. 77, No. 39 / Tuesday, February 28, 2012 / Proposed Rules 11865 

10The term, ‘‘dv,’’ is the abbreviation for 

‘‘deciview.’’ 

best days are presented in Table 1 

below. 

TABLE 1—NATURAL BACKGROUND AND BASELINE CONDITIONS FOR NORTH CAROLINA’S CLASS I AREAS

Class I area 

Average for 

20% worst 

days (dv 10) 

Average for 

20% best 

days (dv) 

Natural Background Conditions: 

Great Smoky Mountains National Park ............................................................................................................ 11.05 4.54 

Joyce Kilmer-Slickrock Wilderness Area .......................................................................................................... 11.05 4.54 

Linville Gorge Wilderness Area ........................................................................................................................ 11.19 4.08 

Shining Rock Wilderness Area ......................................................................................................................... 11.47 2.51 

Swanquarter Wilderness Area .......................................................................................................................... 11.55 5.46 

Baseline Visibility Conditions (2000–2004): 

Great Smoky Mountains National Park ............................................................................................................ 30.28 13.58 

Joyce Kilmer-Slickrock Wilderness Area .......................................................................................................... 30.28 13.58 

Linville Gorge Wilderness Area ........................................................................................................................ 28.77 11.11 

Shining Rock Wilderness Area ......................................................................................................................... 28.46 7.69 

Swanquarter Wilderness Area .......................................................................................................................... 24.74 11.99 

4. Uniform Rate of Progress 

In setting the RPGs, North Carolina 

considered the uniform rate of progress 

needed to reach natural visibility 

conditions by 2064 (‘‘glidepath’’) and 

the emissions reduction measures 

needed to achieve that rate of progress 

over the period of the SIP to meet the 

requirements of 40 CFR 

51.308(d)(1)(i)(B). As explained in 

EPA’s Reasonable Progress Guidance 

document, the uniform rate of progress 

is not a presumptive target, and RPGs 

may be greater than, less than, or 

equivalent to the glidepath. 

The State’s implementation plan 

presents two sets of graphs, one for the 

20 percent best days, and one for the 20 

percent worst days, for its five Class I 

areas. North Carolina constructed the 

graph for the worst days (i.e., the 

glidepath) in accordance with EPA’s 

2003 Tracking Progress Guidance by 

plotting a straight graphical line from 

the baseline level of visibility 

impairment for 2000–2004 to the level 

of visibility conditions representing no 

anthropogenic impairment in 2064 for 

its areas. For the best days, the graph 

includes a horizontal, straight line 

spanning from baseline conditions in 

2004 out to 2018 to depict no 

degradation in visibility over the 

implementation period of the SIP. North 

Carolina’s SIP shows that the State’s 

RPGs for its areas provide for 

improvement in visibility for the 20 

percent worst days over the period of 

the implementation plan and ensure no 

degradation in visibility for the 20 

percent best days over the same period, 

in accordance with 40 CFR 51.308(d)(1). 

For the Great Smoky Mountain and 

Joyce Kilmer Class I areas, the overall 

visibility improvement necessary to 

reach natural conditions is the 

difference between baseline visibility of 

30.28 deciviews for the 20 percent worst 

days and natural conditions of 11.05 

deciviews, i.e., 19.23 deciviews. Over 

the 60-year period from 2004 to 2064, 

this would require an approximate 

improvement of 0.321 deciview per year 

(i.e., 19.23 deciviews/60 years) to reach 

natural conditions. Hence, for the 14- 

year period from 2004 to 2018, in order 

to achieve visibility improvement at 

least equivalent to the uniform rate of 

progress for the 20 percent worst days 

at the Great Smoky Mountain and Joyce 

Kilmer areas, North Carolina would 

need to project at least 4.49 deciviews 

over the first implementation period 

(i.e., 0.321 deciview x 14 years = 4.49 

deciviews) of visibility improvement 

from the 30.28 deciviews baseline in 

2004, resulting in visibility levels at or 

below 25.79 deciviews in 2018. As 

discussed below in section IV.C.7, for 

the Great Smoky Mountain and Joyce 

Kilmer areas, North Carolina projects a 

6.78 deciview improvement to visibility 

from the 30.28 deciview baseline to 

23.50 deciviews in 2018 for the 20 

percent most impaired days, and a 1.47 

deciview improvement to 12.11 

deciviews from the baseline visibility of 

13.58 deciviews for the 20 percent least 

impaired days. Similar computations 

can be made for the other three North 

Carolina Class I areas. 

C. Long-Term Strategy/Strategies 

As described in section III.E of this 

action, the LTS is a compilation of statespecific control measures relied on by a 

state for achieving its RPGs. North 

Carolina’s LTS for the first 

implementation period addresses the 

emissions reductions from federal, state, 

and local controls that take effect in the 

State from the end of the baseline period 

starting in 2004 until 2018. The North 

Carolina LTS was developed by the 

State, in coordination with the VISTAS 

RPO, through an evaluation of the 

following components: (1) Identification 

of the emissions units within North 

Carolina and in surrounding states that 

likely have the largest impacts currently 

on visibility at the State’s Class I areas; 

(2) estimation of emissions reductions 

for 2018 based on all controls required 

or expected under federal and state 

regulations for the 2004–2018 period 

(including BART); (3) comparison of 

projected visibility improvement with 

the uniform rate of progress for the 

State’s Class I areas; and (4) application 

of the four statutory factors in the 

reasonable progress analysis for the 

identified emissions units to determine 

if additional reasonable controls were 

required. 

In a separate action proposing limited 

disapproval of the regional haze SIPs of 

a number of states, EPA noted that these 

states relied on the trading programs of 

CAIR to satisfy the BART requirement 

and the requirement for a LTS sufficient 

to achieve the state-adopted RPGs. See 

76 FR 82219 (December 30, 2011). In 

that action, EPA proposed a limited 

disapproval of North Carolina’s regional 

haze SIP submittal insofar as the SIP 

relied on CAIR. For that reason, EPA is 

not taking action on that aspect of North 

Carolina’s regional haze SIP in this 

action. Comments on the December 30, 

2011, proposed determination are 

accepted at Docket ID No. EPA–HQ– 

OAR–2011–0729. The comment period 

for EPA’s December 30, 2011, proposed 

rulemaking is scheduled to end on 

February 28, 2012. 

mstockstill on DSK4VPTVN1PROD with PROPOSALS

11866 Federal Register / Vol. 77, No. 39 / Tuesday, February 28, 2012 / Proposed Rules 

11See NRDC v. EPA, 489 F.3d 1250 (D.C. Cir. 

2007). 

1. Emissions Inventory for 2018 With 

Federal and State Control Requirements 

The emissions inventory used in the 

regional haze technical analyses was 

developed by VISTAS with assistance 

from North Carolina. The 2018 

emissions inventory was developed by 

projecting 2002 emissions and applying 

reductions expected from federal and 

state regulations affecting the emissions 

of VOC and the visibility-impairing 

pollutants NOX, PM, and SO2. The 

BART Guidelines direct states to 

exercise judgment in deciding whether 

VOC and NH3 impair visibility in their 

Class I area(s). As discussed further in 

section IV.C.3, VISTAS performed 

modeling sensitivity analyses, which 

demonstrated that anthropogenic 

emissions of VOC and NH3 do not 

significantly impair visibility in the 

VISTAS region. Thus, while emissions 

inventories were also developed for NH3

and VOC, and applicable federal VOC 

reductions were incorporated into North 

Carolina’s regional haze analyses, North 

Carolina did not further evaluate NH3

and VOC emissions sources for potential 

controls under BART or reasonable 

progress. 

VISTAS developed emissions for five 

inventory source classifications: 

stationary point and area sources, offroad and on-road mobile sources, and 

biogenic sources. Stationary point 

sources are those sources that emit 

greater than a specified tonnage per 

year, depending on the pollutant, with 

data provided at the facility level. 

Stationary area sources are those 

sources whose individual emissions are 

relatively small, but due to the large 

number of these sources, the collective 

emissions from the source category 

could be significant. VISTAS estimated 

emissions on a countywide level for the 

inventory categories of: (a) Stationary 

area sources; (b) off-road (or non-road) 

mobile sources (i.e., equipment that can 

move but does not use roadways); and 

(c) biogenic sources (which are natural 

sources of emissions, such as trees). Onroad mobile source emissions are 

estimated by vehicle type and road type, 

and are summed to the countywide 

level. 

There are many federal and state 

control programs being implemented 

that VISTAS and North Carolina 

anticipate will reduce emissions 

between the end of the baseline period 

and 2018. Emissions reductions from 

these control programs are projected to 

achieve substantial visibility 

improvement by 2018 in the North 

Carolina Class I areas. The control 

programs relied upon by North Carolina 

include CAIR; EPA’s NOX SIP Call; 

North Carolina’s Clean Smokestacks Act 

(CSA); Georgia Rule 391–3–1– 

.02(2)(sss), ‘‘Multipollutant Control for 

Electric Utility Steam Generating 

Units;’’ consent decrees for Tampa 

Electric, Virginia Electric and Power 

Company, Gulf Power-Plant Crist, and 

American Electric Power; NOX and/or 

VOC reductions from the control rules 

in 1-hour ozone SIPs for Atlanta, 

Birmingham, and Northern Kentucky; 

North Carolina’s NOX Reasonably 

Available Control Technology state rule 

for Philip Morris USA and Norandal 

USA in the Charlotte/Gastonia/Rock 

Hill 1997 8-hour ozone nonattainment 

area; federal 2007 heavy duty diesel 

engine standards for on-road trucks and 

buses; federal Tier 2 tailpipe controls for 

on-road vehicles; federal large spark 

ignition and recreational vehicle 

controls; and EPA’s non-road diesel 

rules. Controls from various federal 

Maximum Achievable Control 

Technology (MACT) rules were also 

utilized in the development of the 2018 

emissions inventory projections. These 

MACT rules include the industrial 

boiler/process heater MACT (referred to 

as ‘‘Industrial Boiler MACT’’), the 

combustion turbine and reciprocating 

internal combustion engines MACTs, 

and the VOC 2-, 4-, 7-, and 10-year 

MACT standards. 

Effective July 30, 2007, the D.C. 

Circuit mandated the vacatur and 

remand of the Industrial Boiler MACT 

Rule.11 This MACT was vacated since it 

was directly affected by the vacatur and 

remand of the Commercial and 

Industrial Solid Waste Incinerator 

Definition Rule. EPA proposed a new 

Industrial Boiler MACT rule to address 

the vacatur on June 4, 2010, (75 FR 

32006) and issued a final rule on March 

21, 2011 (76 FR 15608). The VISTAS 

modeling included emissions 

reductions from the vacated Industrial 

Boiler MACT rule, and North Carolina 

did not redo its modeling analysis when 

the rule was re-issued. Even though 

North Carolina’s modeling is based on 

the vacated Industrial Boiler MACT 

limits, the State’s modeling conclusions 

are unlikely to be affected because the 

expected reductions due to the vacated 

rule were relatively small compared to 

the State’s total SO2, PM2.5, and coarse 

particulate matter (PM10) emissions in 

2018 (i.e., 0.1 to 0.4 percent, depending 

on the pollutant, of the projected 2018 

SO2, PM2.5, and PM10 inventory). Thus, 

EPA does not expect that differences 

between the vacated and final Industrial 

Boiler MACT emissions limits would 

affect the adequacy of the existing North 

Carolina regional haze SIP. If there is a 

need to address discrepancies between 

projected emissions reductions from the 

vacated Industrial Boiler MACT and the 

Industrial Boiler MACT issued March 

21, 2011 (76 FR 15608), EPA expects 

North Carolina to do so in the State’s 

five-year progress report. 

Below in Tables 2 and 3 are 

summaries of the 2002 baseline and 

2018 estimated emissions inventories 

for North Carolina. 

TABLE 2—2002 EMISSIONS INVENTORY SUMMARY FOR NORTH CAROLINA

[Tons per year] 

VOC NOX PM2.5 PM10 NH3 SO2

Point ......................................................... 61,484 196,731 26,953 36,539 1,233 522,093 

Area .......................................................... 250,044 41,517 83,520 300,838 162,183 5,815 

On-Road Mobile ....................................... 263,766 327,329 4,623 6,579 9,702 12,420 

Off-Road Mobile ....................................... 94,480 84,284 7,348 7,348 65 7,693 

Total .................................................. 669,774 649,861 122,444 351,304 173,183 548,021 

mstockstill on DSK4VPTVN1PROD with PROPOSALS

Federal Register / Vol. 77, No. 39 / Tuesday, February 28, 2012 / Proposed Rules 11867 

TABLE 3—2018 EMISSIONS INVENTORY SUMMARY FOR NORTH CAROLINA

[Tons per year] 

VOC NOX PM2.5 PM10 NH3 SO2

Point ......................................................... 71,247 94,276 37,789 48,354 2,073 148,972 

Area .......................................................... 203,132 49,514 93,406 338,872 181,333 6,674 

On-Road Mobile ....................................... 101,099 87,791 2,123 4,392 14,065 1,481 

Off-road Mobile ........................................ 61,327 49,046 4,069 4,298 83 905 

Total .................................................. 436,805 280,627 137,387 395,916 197,554 158,032 

2. Modeling To Support the LTS and 

Determine Visibility Improvement for 

Uniform Rate of Progress 

VISTAS performed modeling for the 

regional haze LTS for the 10 

southeastern states, including North 

Carolina. The modeling analysis is a 

complex technical evaluation that began 

with selection of the modeling system. 

VISTAS used the following modeling 

system: 

• Meteorological Model: The 

Pennsylvania State University/National 

Center for Atmospheric Research 

Mesoscale Meteorological Model is a 

nonhydrostatic, prognostic 

meteorological model routinely used for 

urban- and regional-scale 

photochemical, PM2.5, and regional haze 

regulatory modeling studies. 

• Emissions Model: The Sparse 

Matrix Operator Kernel Emissions 

modeling system is an emissions 

modeling system that generates hourly 

gridded speciated emissions inputs of 

mobile, non-road mobile, area, point, 

fire and biogenic emissions sources for 

photochemical grid models. 

• Air Quality Model: The EPA’s 

Models-3/Community Multiscale Air 

Quality (CMAQ) modeling system is a 

photochemical grid model capable of 

addressing ozone, PM, visibility and 

acid deposition at a regional scale. The 

photochemical model selected for this 

study was CMAQ version 4.5. It was 

modified through VISTAS with a 

module for Secondary Organics 

Aerosols in an open and transparent 

manner that was also subjected to 

outside peer review. 

CMAQ modeling of regional haze in 

the VISTAS region for 2002 and 2018 

was carried out on a grid of 12x12 

kilometer cells that covers the 10 

VISTAS states (Alabama, Florida, 

Georgia, Kentucky, Mississippi, North 

Carolina, South Carolina, Tennessee, 

Virginia, West Virginia) and states 

adjacent to them. This grid is nested 

within a larger national CMAQ 

modeling grid of 36x36 kilometer cells 

that covers the continental United 

States, portions of Canada and Mexico, 

and portions of the Atlantic and Pacific 

Oceans along the east and west coasts. 

Selection of a representative period of 

meteorology is crucial for evaluating 

baseline air quality conditions and 

projecting future changes in air quality 

due to changes in emissions of 

visibility-impairing pollutants. VISTAS 

conducted an in-depth analysis which 

resulted in the selection of the entire 

year of 2002 (January 1–December 31) as 

the best period of meteorology available 

for conducting the CMAQ modeling. 

The VISTAS states modeling was 

developed consistent with EPA’s 

Guidance on the Use of Models and 

Other Analyses for Demonstrating 

Attainment of Air Quality Goals for 

Ozone, PM2.5, and Regional Haze, 

located at http://www.epa.gov/ 

scram001/guidance/guide/final-03-pmrh-guidance.pdf, (EPA–454/B–07–002), 

April 2007, and EPA document, 

Emissions Inventory Guidance for 

Implementation of Ozone and 

Particulate Matter National Ambient Air 

Quality Standards (NAAQS) and 

Regional Haze Regulations, located at 

http://www.epa.gov/ttnchie1/eidocs/ 

eiguid/index.html, EPA–454/R–05–001, 

August 2005, updated November 2005 

(‘‘EPA’s Modeling Guidance’’). 

VISTAS examined the model 

performance of the regional modeling 

for the areas of interest before 

determining whether the CMAQ model 

results were suitable for use in the 

regional haze assessment of the LTS and 

for use in the modeling assessment. The 

modeling assessment predicts future 

levels of emissions and visibility 

impairment used to support the LTS 

and to compare predicted, modeled 

visibility levels with those on the 

uniform rate of progress. In keeping 

with the objective of the CMAQ 

modeling platform, air quality model 

performance was evaluated using 

graphical and statistical assessments 

based on measured ozone, fine particles, 

and acid deposition from various 

monitoring networks and databases for 

the 2002 base year. VISTAS used a 

diverse set of statistical parameters from 

the EPA’s Modeling Guidance to stress 

and examine the model and modeling 

inputs. Once VISTAS determined the 

model performance to be acceptable, 

VISTAS used the model to assess the 

2018 RPGs using the current and future 

year air quality modeling predictions, 

and compared the RPGs to the uniform 

rate of progress. 

In accordance with 40 CFR 

51.308(d)(3), the State of North Carolina 

provided the appropriate supporting 

documentation for all required analyses 

used to determine the State’s LTS. The 

technical analyses and modeling used to 

develop the glidepath and to support 

the LTS are consistent with EPA’s RHR 

and interim and final EPA Modeling 

Guidance. EPA proposes to accept the 

VISTAS technical modeling to support 

the LTS and to determine visibility 

improvement for the uniform rate of 

progress because the modeling system 

was chosen and simulated according to 

EPA Modeling Guidance. EPA proposes 

to concur with the VISTAS model 

performance procedures and results, 

and that the CMAQ is an appropriate 

tool for the regional haze assessments 

for the North Carolina LTS and regional 

haze SIP. 

3. Relative Contributions to Visibility 

Impairment: Pollutants, Source 

Categories, and Geographic Areas 

An important step toward identifying 

reasonable progress measures is to 

identify the key pollutants contributing 

to visibility impairment at each Class I 

area. To understand the relative benefit 

of further reducing emissions from 

different pollutants, source sectors, and 

geographic areas, VISTAS developed 

emissions sensitivity model runs using 

CMAQ to evaluate visibility and air 

quality impacts from various groups of 

emissions and pollutant scenarios in the 

Class I areas on the 20 percent worst 

visibility days. 

Regarding which pollutants are most 

significantly impacting visibility in the 

VISTAS region, VISTAS’ contribution 

assessment, based on IMPROVE 

monitoring data, demonstrated that 

ammonium sulfate is the major 

contributor to PM2.5 mass and visibility 

impairment at Class I areas in the 

VISTAS and neighboring states. On the 

20 percent worst visibility days in 

2000–2004, ammonium sulfate 

mstockstill on DSK4VPTVN1PROD with PROPOSALS

11868 Federal Register / Vol. 77, No. 39 / Tuesday, February 28, 2012 / Proposed Rules 

accounted for 75 to 87 percent of the 

calculated light extinction at the inland 

Class I areas in VISTAS, and 69 to 74 

percent of the calculated light extinction 

for all but one of the coastal Class I areas 

in the VISTAS states. In particular, 

sulfate particles resulting from SO2

emissions contribute to the calculated 

light extinction on the haziest days 

roughly 74 percent for the Swanquarter 

area, and 84 to 87 percent for the Great 

Smoky Mountains, Linville Gorge, and 

Shining Rock areas, depending on the 

area. In contrast, ammonium nitrate 

contributed less than five percent of the 

calculated light extinction at the 

VISTAS Class I areas on the 20 percent 

worst visibility days. Particulate organic 

matter (organic carbon) accounted for 20 

percent or less of the light extinction on 

the 20 percent worst visibility days at 

the VISTAS Class I areas. 

VISTAS grouped its 18 Class I areas 

into two types, either ‘‘coastal’’ or 

‘‘inland’’ (sometimes referred to as 

‘‘mountain’’) sites, based on common/ 

similar characteristics (e.g. terrain, 

geography, meteorology), to better 

represent variations in model sensitivity 

and performance within the VISTAS 

region and to describe the common 

factors influencing visibility conditions 

in the two types of Class I areas. All of 

North Carolina’s Class I areas, except for 

Swanquarter, are ‘‘inland’’ areas. 

Swanquarter is considered a ‘‘coastal’’ 

area. 

Results from VISTAS’ emissions 

sensitivity analyses indicate that sulfate 

particles resulting from SO2 emissions 

are the dominant contributor to 

visibility impairment on the 20 percent 

worst days at all Class I areas in 

VISTAS. North Carolina concluded that 

reducing SO2 emissions from EGU and 

non-EGU point sources in the VISTAS 

states would have the greatest visibility 

benefits for the North Carolina Class I 

areas. 

Because ammonium nitrate is a small 

contributor to PM2.5 mass and visibility 

impairment on the 20 percent worst 

days at the inland Class I areas in 

VISTAS, which include all of the North 

Carolina Class I areas except for the 

Swanquarter area, the benefits of 

reducing NOX and NH3 emissions at 

these sites are small. Some of the worst 

days at Swanquarter, and other coastal 

sites within the VISTAS region, occur in 

the winter when ammonium nitrate has 

a somewhat larger contribution to 

visibility impairment. North Carolina 

concluded that reducing ammonia 

emissions would be more beneficial for 

reducing ammonium nitrate 

contributions to visibility impairment in 

wintertime than further reducing NOX

emissions from either ground-level or 

point (elevated) sources. NCDAQ notes 

that for Swanquarter, the numerous hog 

farms in eastern North Carolina are the 

likely primary emissions sources for 

ammonia. 

The VISTAS sensitivity analyses 

show that VOC emissions from biogenic 

sources such as vegetation also 

contribute to visibility impairment. 

However, control of these biogenic 

sources of VOC would be extremely 

difficult, if not impossible. The 

anthropogenic sources of VOC 

emissions are minor compared to the 

biogenic sources. Therefore, controlling 

anthropogenic sources of VOC 

emissions would have little, if any, 

visibility benefits at the Class I areas in 

the VISTAS region, including North 

Carolina. The sensitivity analyses also 

show that reducing primary carbon from 

point sources, ground level sources, or 

fires is projected to have small to no 

visibility benefit at the VISTAS Class I 

areas. 

North Carolina considered the factors 

listed under 40 CFR 51.308(d)(3)(v) and 

in section III.E. of this action to develop 

its LTS as described below. North 

Carolina, in conjunction with VISTAS, 

demonstrated in its SIP that elemental 

carbon (a product of highway and nonroad diesel engines, agricultural 

burning, prescribed fires, and wildfires), 

fine soils (a product of construction 

activities and activities that generate 

fugitive dust), and ammonia are 

relatively minor contributors to 

visibility impairment at the Class I areas 

in North Carolina. North Carolina 

considered agricultural and forestry 

smoke management techniques to 

address visibility impacts from 

elemental carbon. NCDAQ stated in its 

SIP that it is working with the North 

Carolina Division of Forest Resources to 

develop a smoke management program 

that utilizes basic smoke management 

practices and addresses the issues laid 

out in the EPA’s 1998 Interim Air 

Quality Policy on Wildland and 

Prescribed Fires available at: http:// 

www.epa.gov/ttncaaa1/t1/memoranda/ 

firefnl.pdf. Additionally, NCDAQ is 

working with the North Carolina 

Department of Agriculture to develop a 

Memorandum of Understanding 

regarding agricultural burning. 

With regard to fine soils, the State 

considered those activities that generate 

fugitive dust, including construction 

activities. With regard to construction 

activities, the North Carolina 

Department of Transportation’s Division 

of Highways has issued regulations 

addressing control of erosion, siltation, 

and pollution from construction 

activities. In addition, NCDAQ 

promulgated state rule 15A NCAC 

02D.0540, ‘‘Particulates From Fugitive 

Dust Emission Sources,’’ effective on 

September 1, 2007, to control 

particulates from fugitive dust 

emissions sources generated within 

plant boundaries from activities such as 

‘‘unloading and loading areas, process 

areas, stockpiles, stock pile working, 

plant parking lots, and plant roads 

(including access roads and haul 

roads).’’ The State has chosen not to 

develop controls for fine soils in this 

first implementation period because of 

their relatively minor contribution to 

visibility impairment. 

With regard to ammonia emissions 

from agricultural sources, NCDAQ, as a 

continuation of the State’s CSA, 

initiated the Climate Action Planning 

Advisory Group to develop options for 

the reduction of greenhouse gas 

emissions in North Carolina, including 

the emissions from agriculture and 

agricultural waste in North Carolina. 

The Group issued a report that supports 

expanded research, regulatory actions, 

and grant guarantees as key 

implementation tools to accomplish the 

expanded utilization of methane (a 

greenhouse gas) from hog/cattle waste 

for energy. The report also highlights 

improved waste management practices 

as important. A co-benefit of any 

resulting measures will be the reduction 

of ammonia emissions from animal 

waste. In addition, the North Carolina 

Legislature approved a bill on July 26, 

2007, that permanently bans new 

lagoons at hog farms and orders state 

regulators to set environmental 

standards for new hog farm waste 

systems. The new legislation phases-out 

the use of waste lagoons by hog farmers, 

replacing them with more 

environmentally friendly systems. 

EPA preliminarily concurs with the 

State’s technical demonstration showing 

that elemental carbon, fine soils, and 

ammonia are not significant 

contributors to visibility in the State’s 

Class I areas, and therefore, proposes to 

find that North Carolina has adequately 

satisfied 40 CFR 51.308(d)(3)(v). EPA’s 

TSD to this Federal Register action and 

North Carolina’s SIP provide more 

details on the State’s consideration of 

these factors for North Carolina’s LTS. 

The emissions sensitivity analyses 

conducted by VISTAS predict that 

reductions in SO2 emissions from EGU 

and non-EGU industrial point sources 

will result in the greatest improvements 

in visibility in the Class I areas in the 

VISTAS region, more than any other 

visibility-impairing pollutant. Specific 

to North Carolina, the VISTAS 

sensitivity analysis projects visibility 

benefits on the 20 percent worst days at 

the State’s four inland Class I areas from 

mstockstill on DSK4VPTVN1PROD with PROPOSALS

Federal Register / Vol. 77, No. 39 / Tuesday, February 28, 2012 / Proposed Rules 11869 

12Prior to VISTAS, the southern states cooperated 

in a voluntary regional partnership ‘‘to identify and 

recommend reasonable measures to remedy existing 

and prevent future adverse effects from humaninduced air pollution on the air quality related 

values of the Southern Appalachian Mountains.’’ 

States cooperated with FLMs, EPA, industry, 

environmental organizations, and academia to 

complete a technical assessment of the impacts of 

acid deposition, ozone, and fine particles on 

sensitive resources in the Southern Appalachians. 

The SAMI Final Report was delivered in August 

2002. 

SO2 reductions from EGUs in eight of 

the 10 VISTAS states: Alabama, Georgia, 

Kentucky, North Carolina, South 

Carolina, Tennessee, Virginia, and West 

Virginia. For the Swanquarter area, 

reductions from EGUs in North Carolina 

and South Carolina would have the 

greatest benefits; the contributions from 

other VISTAS states are comparatively 

small. Additional, smaller benefits are 

projected for North Carolina’s Class I 

areas from SO2 emissions reductions 

from non-utility industrial point sources 

in the VISTAS states. SO2 emissions 

contributions to visibility impairment 

from other RPO regions are 

comparatively small in contrast to the 

VISTAS states’ contributions, and thus, 

controlling sources outside of the 

VISTAS region is predicted to provide 

less significant improvements in 

visibility in the Class I areas in VISTAS. 

Taking the VISTAS sensitivity 

analyses results into consideration, 

North Carolina concluded that reducing 

SO2 emissions from EGU and non-EGU 

point sources in certain VISTAS states 

would have the greatest visibility 

benefits for the North Carolina Class I 

areas. The State chose to focus solely on 

evaluating certain SO2 sources 

contributing to visibility impairment to 

the State’s Class I areas for additional 

emissions reductions for reasonable 

progress in this first implementation 

period (described in sections IV.C.4 and 

IV.C.5 of this action). EPA proposes to 

agree with the State’s analyses and 

conclusions used to determine the 

pollutants and source categories that 

most contribute to visibility impairment 

in the North Carolina Class I areas, and 

proposes to find the State’s approach to 

focus on developing a LTS that includes 

largely additional measures for point 

sources of SO2 emissions to be 

appropriate. 

SO2 sources for which it is 

demonstrated that no additional 

controls are reasonable in this current 

implementation period will not be 

exempted from future assessments for 

controls in subsequent implementation 

periods or, when appropriate, from the 

five-year periodic SIP reviews. In future 

implementation periods, additional 

controls on these SO2 sources evaluated 

in the first implementation period may 

be determined to be reasonable, based 

on a reasonable progress control 

evaluation, for continued progress 

toward natural visibility conditions for 

the 20 percent worst days and to avoid 

further degradation of the 20 percent 

best days. Similarly, in subsequent 

implementation periods, the State may 

use different criteria for identifying 

sources for evaluation and may consider 

other pollutants as visibility conditions 

change over time. 

4. Procedure for Identifying Sources To 

Evaluate for Reasonable Progress 

Controls in North Carolina and 

Surrounding Areas 

As discussed in section IV.C.3 of this 

action, through comprehensive 

evaluations by VISTAS and the 

Southern Appalachian Mountains 

Initiative (SAMI),12 the VISTAS states 

concluded that sulfate particles 

resulting from SO2 emissions account 

for the greatest portion of the regional 

haze affecting the Class I areas in 

VISTAS states, including those areas in 

North Carolina. Utility and non-utility 

boilers are the main sources of SO2

emissions within the southeastern 

United States. VISTAS developed a 

methodology for North Carolina that 

enables the State to focus its reasonable 

progress analysis on those geographic 

regions and source categories that 

impact visibility at its Class I areas. 

Recognizing that there was neither 

sufficient time nor adequate resources 

available to evaluate all emissions units 

within a given area of influence (AOI) 

around each of the Class I areas that 

North Carolina’s sources impact, the 

State established a threshold to 

determine which emissions units would 

be evaluated for reasonable progress 

control. In applying this methodology, 

NCDAQ first calculated the fractional 

contribution to visibility impairment 

from all emissions units within the SO2

AOI for its Class I areas, and from those 

units within the SO2 AOIs surrounding 

Class I areas in other states potentially 

impacted by emissions from emissions 

units in North Carolina. The State then 

identified those emissions units with a 

contribution of one percent or more to 

the visibility impairment at that 

particular Class I area, and evaluated 

each of these units for control measures 

for reasonable progress using the 

following four ‘‘reasonable progress 

factors’’ required under 40 CFR 

51.308(d)(1)(i)(A): (i) Cost of 

compliance; (ii) time necessary for 

compliance; (iii) energy and non-air 

quality environmental impacts of 

compliance; and (iv) remaining useful 

life of the emissions unit. 

North Carolina’s SO2 AOI 

methodology captured greater than 60 

percent of the total point source SO2

contribution to visibility impairment in 

four of the five Class I areas in North 

Carolina, and required an evaluation of 

21 emissions units at seven facilities in 

North Carolina. At the remaining Class 

I area, Swanquarter, the one percent 

threshold represents 47 percent of the 

total point source SO2 contribution, 

while requiring an evaluation of 12 

additional units at six facilities in North 

Carolina. The NCDAQ also looked at 

what sources in North Carolina may be 

impacting Class I areas located outside 

of the State, as well as what sources 

located outside of North Carolina may 

be impacting the North Carolina Class I 

areas. By applying the State’s AOI SO2

methodology, the only North Carolina 

source that was identified as potentially 

impacting visibility in a Class I area 

outside the State was the Duke PowerDan River facility, which may impact 

the James River Face Wilderness Area in 

Virginia. To capture a higher percentage 

of emissions units contributing to the 

total sulfate visibility impairment would 

involve an evaluation of many more 

units that have substantially less 

impact. 

NCDAQ believes that the one percent 

threshold is appropriate given the 

contribution to the total sulfate visibility 

impairment at each Class I area and the 

limited resources available to conduct a 

unit-by-unit evaluation for reasonable 

progress. EPA believes the approach 

developed by VISTAS and implemented 

for the Class I areas in North Carolina 

is a reasonable methodology to 

prioritize the most significant 

contributors to regional haze and to 

identify sources to assess for reasonable 

progress control. The approach is 

consistent with EPA’s Reasonable 

Progress Guidance. The technical 

approach of VISTAS and North Carolina 

was objective and based on several 

analyses, including the evaluation of a 

large universe of emissions units within 

and surrounding the State of North 

Carolina and all of the 18 VISTAS Class 

I areas. It also included an analysis of 

the VISTAS emissions units affecting 

nearby Class I areas surrounding the 

VISTAS states that are located in other 

RPOs’ Class I areas. 

5. Application of the Four CAA Factors 

in the Reasonable Progress Analysis 

NCDAQ identified 34 emissions units 

at 14 facilities in North Carolina (see 

Table 4) with SO2 emissions that were 

above the State’s minimum threshold 

for reasonable progress evaluation 

mstockstill on DSK4VPTVN1PROD with PROPOSALS

11870 Federal Register / Vol. 77, No. 39 / Tuesday, February 28, 2012 / Proposed Rules 

13See also EPA’s TSD, section III.C.2, fractional 

contribution analysis tables for each Class I area, 

excerpted from the North Carolina SIP, Appendix 

H. 

because they were modeled to fall 

within the SO2 AOI of any Class I area 

and have a one percent or greater 

contribution to the sulfate visibility 

impairment in at least one Class I area.13

Of these 34 units, seven emissions units 

were not subject to a reasonable 

progress analysis because they were 

already subject to BART or had shut 

down. In addition, as discussed in 

section IV.C.5.B, 16 units are subject to 

CAIR, and NCDAQ concluded that no 

additional controls for SO2 beyond 

CAIR for subject EGUs are reasonable 

for this first implementation period. 

NCDAQ evaluated 11 units at five 

facilities. 

TABLE 4—NORTH CAROLINA FACILITIES WITH EMISSIONS UNIT(S) SUBJECT TO REASONABLE PROGRESS ANALYSIS: 

Facilities With Emissions Unit(s) Subject to Reasonable Progress Analysis 

Blue Ridge Paper Products—Canton Mill G–24, G–25, G–65, G–66 

Cogentrix Kenansville—Gen1 

PCS Phosphate Company Inc.—Aurora G–1034, G–1035 

Weyerhaeuser Company—New Bern G–42 

Weyerhaeuser Company—Plymouth G–140, G–143, G–148 

Facilities With Unit(s) Found Not Subject to Reasonable Progress Analysis: 

EGUs Subject to CAIR Within AOI of Any Class I Area: 

Carolina Power & Light Asheville Steam E1, E2 

Duke Energy Corporation—Buck Steam Station G–4, G–5 

Duke Energy Corporation—Dan River Station G–21 

Duke Energy Corporation—Cliffside Steam G–86, G–87, G–88 

Duke Energy Corporation—Marshall Steam G–1, G–2 

Duke Energy Corporation—Riverbend Steam G–17, G–19, G–20 

L V Sutton Steam Electric Plant G–188 

Progress Energy—F Lee Plant G–2, G–3 

Emissions Units Subject to BART: 

Blue Ridge Paper Products—Canton Mill G–26, G–31, G–32 

Emissions Units that Shut Down: 

PCS Phosphate Company Inc.—Aurora G–1032, G–1033 

Ecusta Business Development Center LLC—G–28, G–29 

A. Facilities With Emissions Unit(s) 

Subject to Reasonable Progress Analysis 

NCDAQ analyzed whether SO2

controls should be required for 11 

emissions units at five facilities based 

on a consideration of the four factors set 

out in the CAA and EPA’s regulations. 

For the limited purpose of evaluating 

the cost of compliance for the 

reasonable progress assessment in this 

first regional haze SIP, NCDAQ believed 

that it was not equitable to require nonEGUs to bear a greater economic burden 

than EGUs for a given control strategy. 

The facility-by-facility costs for EGUs 

under CSA ranged from 912 to 1,922 

dollars per ton of SO2 removed ($/ton 

SO2), and the average costs per utility 

system ranged from $1,231 to $1,375/ 

ton SO2. These costs were estimated 

using the capital costs from the CSA 

2006 compliance plans and the 

projected operating costs provided by 

Duke Energy and Progress Energy. These 

costs were used as a guide in 

determining cost effectiveness. 

During the current reasonable 

progress assessment, no emissions units 

in North Carolina were identified for 

additional control since no measures 

were found to be below the cost 

threshold discussed above. NCDAQ did 

not perform an exhaustive review of the 

remaining three statutory factors for 

reasonable progress since it did not 

identify any cost-effective control 

measures for the specific sources with 

contributions to Class I areas in North 

Carolina or neighboring states. Neither 

the time necessary for compliance nor 

the energy and non-air quality 

environmental impacts of compliance 

appear to be out of the ordinary for the 

control measures identified for these 

facilities. A likely short remaining 

useful life for two units was noted in 

one case, but a longer remaining useful 

life would not alter the reasonable 

progress determination for those units. 

North Carolina also noted that, in 

order to show continued progress past 

2018, the criteria will likely be different 

in the next reasonable progress 

assessment in order to maintain 

continuous visibility improvement 

toward natural background conditions 

by 2064. The facilities in North Carolina 

that have units that contribute at least 

one percent to visibility impairment at 

any Class I area in the State, or in 

neighboring states, were sent letters 

from NCDAQ indicating that while no 

additional controls were identified 

during this reasonable progress 

assessment, these sources will evaluate 

possible SO2 reduction strategies for the 

next regional haze SIP due July 31, 

2018. 

1. Blue Ridge Paper Products 

Four coal-fired Power Boilers at Blue 

Ridge Paper Products were evaluated for 

reasonable progress: No. 4 Power Boiler 

(G–66) with a capacity of 535 million 

British thermal units per hour (MMBtu/ 

hr) and boilers G–24, G–25, and G–65, 

each with a capacity of 364–399 

MMBtu/hr. Boilers G–24, G–25, and G– 

65 burn a washed and blended coal 

from different portions of the coal seam 

at the Apollo mine to meet Blue Ridge 

Paper’s specifications for heat, ash and 

sulfur content. Coal from the Apollo 

mine has high heat content, low to 

moderate ash, and low to moderate 

sulfur, and it averages from 1.4 to 1.5 

pounds SO2 per million British Thermal 

Units (lbs SO2/MMBtu). The 

electrostatic precipitators (ESPs) on 

these boilers perform well on this 

moderate sulfur coal and test well below 

applicable PM standards. They are not 

designed, however, to burn low sulfur 

coal. Ash from low sulfur coal has a 

higher resistivity than ash from the 

moderate sulfur coal that Blue Ridge 

Paper burns in these boilers. The No. 4 

Power Boiler burns washed, low sulfur 

coal subject to new source performance 

standards (NSPS) with a sulfur limit of 

1.2 lbs SO2/MMBtu. 

Based on information from the 

company, this lower sulfur coal is $75– 

$90/ton SO2, and the other coal used at 

mstockstill on DSK4VPTVN1PROD with PROPOSALS

Federal Register / Vol. 77, No. 39 / Tuesday, February 28, 2012 / Proposed Rules 11871 

the facility is $65/ton SO2. The cost 

difference is $10–25/ton SO2. The 

company burned 277,214 tons of higher 

sulfur coal in 2005; switching to lower 

sulfur coal would cost approximately 

$2,772,140–$6,930,350 extra per year. If 

1,400 tons of SO2 were reduced by 

switching from the current higher sulfur 

coal (one percent sulfur or 

approximately 1.6 lb SO2/MMBtu) to 

lower sulfur coal (0.75 percent sulfur or 

approximately 1.2 lb SO2/MMBtu) at the 

2005 rate of coal consumption, 

associated costs would range from 

$1,980–$4,950/ton SO2 with an average 

cost of $3,465/ton SO2. NCDAQ 

determined that the cost for add-on 

control technology for these units ranges 

from $12,055 to $100,961/ton SO2. 

NCDAQ concluded that there are no 

cost-effective controls available for these 

units at this time within the cost 

threshold established for this reasonable 

progress assessment. Although NCDAQ 

has concluded that there are no costeffective controls for this reasonable 

progress period, the State acknowledges 

that the emissions from Blue Ridge 

Paper Products impact North Carolina’s 

inland Class I areas. NCDAQ notified 

the company that although additional 

controls are not required during this 

implementation period, the State may 

require the installation and operation of 

controls for future implementation 

periods. NCDAQ is committed to 

working with this company over the 

next review period and encouraging the 

company to modernize some of its 

processes with more efficient equipment 

with lower emissions. 

2. PCS Phosphate 

Two of the four sulfuric acid units at 

PCS Phosphate identified for further 

analysis under reasonable progress 

remain in operation (units 1034 and 

1035). On February 7, 2011, NCDAQ 

provided a technical supplement to the 

December 17, 2007, regional haze SIP 

for these units. The two PCS Phosphate 

units currently utilize dual absorption 

systems with a vanadium catalyst. The 

four technologies reviewed included 

sodium bisulfite scrubbing, molecular 

sieve, ammonia scrubbing, and dual 

absorption process with cesiumpromoted catalyst. 

The first three technologies were 

rejected because they have not been 

commercially demonstrated to reliably 

meet current NSPS and state permit 

limits. The use of cesium-promoted 

catalyst was further evaluated, looking 

at three scenarios. The first scenario 

evaluated, changing to a cesiumpromoted catalyst without making other 

major capital investments, was 

estimated to cost $2,879/ton SO2 and 

reduce SO2 emissions by only 165 tons 

per year. This estimate was based on 

reducing SO2 emissions from 3.8 to 3.5 

lbs SO2/ton of sulfuric acid produced. 

The other two scenarios evaluated 

meeting a 2.0 lbs SO2/ton of sulfuric 

acid produced limit by either making 

operational changes or by modifying the 

reactor vessel. The operational changes 

could be made without significant 

capital expenditures but would 

significantly reduce production 

capacity. Modifying the unit to increase 

the amount of catalyst available 

required significant capital investment. 

NCDAQ estimated that these options 

would reduce SO2 emissions by 2,073 

tons/year with a cost effectiveness of 

approximately $11,347/ton of SO2

reduced for the operational change and 

a cost effectiveness of approximately 

$12,816 to $13,651/ton SO2 for the unit 

modification. NCDAQ also cited 

modeling analyses which concluded 

that the visibility improvement at the 

Swanquarter Wilderness Area resulting 

from reducing the SO2 emissions rate by 

1.0 lb SO2/ton sulfuric acid produced 

(i.e., a change in emissions rate from 4.0 

to 3.0 lbs SO2/ton sulfuric acid 

produced) would only be 0.16 deciview. 

Therefore, NCDAQ concluded that there 

are no cost-effective controls available 

for these units at this time within the 

cost threshold established for this 

reasonable progress assessment. NCDAQ 

notified the company that although 

additional controls are not being 

required during this planning period, 

the State may require the installation 

and operation of controls for futureplanning periods. 

3. Weyerhaeuser—Plymouth 

Weyerhaeuser—Plymouth has three 

power boilers subject to analysis: Riley 

No. 1 Combination Boiler, No. 1 Hog 

Fuel Boiler, and No. 2 Hog Fuel Boiler. 

The Riley No. 1 Combination Boiler 

burns coal, No. 6 fuel oil, Low Volume 

High Concentration (LVHC) gases, and 

Stripper Off Gas (SOG) gases and is fired 

at 624 MMBtu/hr maximum heat input. 

The No. 1 Hog Fuel Boiler burns hog 

fuel (wood waste), No. 6 fuel oil, coal, 

used oil, sludge, and High Volume Low 

Concentration (HVLC) gases. This boiler 

is fired at 835 MMBtu/hr maximum heat 

input from hog fuel, 617 MMBtu/hr 

maximum heat input from No. 6 fuel oil, 

or for combination firing, 701.2 and 

319.8 MMBtu/hr maximum heat input 

from hog fuel and coal, respectively. 

The No. 2 Hog Fuel Boiler burns hog 

fuel, No. 6 fuel oil, coal, used oil, 

sludge, HVLC, LVHC, and SOG gases. It 

is fired at 889 MMBtu/hr maximum heat 

input from combined fuels or 800 

MMBtu/hr maximum heat input from 

No. 6 fuel oil. 

NCDAQ did not identify any available 

controls for the Hog Boiler 1 or 2. For 

the Riley Boiler, the only available 

control that NCDAQ identified is a flue 

gas desulfurization (FGD) scrubber at a 

cost of $20,460/ton SO2. Therefore, 

NCDAQ concluded that there are no 

cost-effective controls for these units at 

this time within the cost threshold 

established for this reasonable progress 

assessment. 

4. Weyerhaeuser—New Bern 

Weyerhaeuser—New Bern has one 

power boiler which burns residual oil. 

It is fired at 579 MMBtu/hr maximum 

heat input rate. The only available 

control identified by NCDAQ is an FGD 

at a cost of $17,317/ton SO2. Therefore, 

the NCDAQ concluded that there are no 

cost-effective controls available for this 

unit at this time within the cost 

threshold established for this reasonable 

progress assessment. 

5. Cogentrix Kenansville 

The affected emissions unit at 

Cogentrix Kenansville is Gen1, a 215 

MMBtu/hr heat input mixed fuel-fired 

EGU capable of burning coal, natural 

gas, No. 2 and No. 4 fuel oil, tire-derived 

fuel, pelletized paper fuel, flyash 

briquette, and wood. Although the 

company retains coal as a permitted fuel 

on the permit, it is currently burning 

unadulterated wood (pure wood with 

up to five percent impurities), and its 

new business plan is to continue 

burning only wood as part of the ‘‘green 

power’’ movement in North Carolina. 

The 2005 actual SO2 emissions for 

this unit were 23.25 tons, whereas the 

projected 2018 SO2 emissions were 

1,833.8 tons based on using coal. In the 

final SIP submittal, the NCDAQ stated 

that it is sending the company a letter 

indicating that they are currently on the 

list of sources contributing greater than 

one percent to the total sulfate visibility 

impairment at the Swanquarter 

Wilderness Area based on the estimated 

emissions from burning coal. The SIP 

submittal indicated that the letter will 

suggest that the facility change its 

permit to remove coal as a possible fuel 

source for this unit. 

6. EPA Assessment 

As noted in EPA’s Reasonable 

Progress Guidance, the states have wide 

latitude to determine appropriate 

additional control requirements for 

ensuring reasonable progress, and there 

are many ways for a state to approach 

identification of additional reasonable 

measures. States must consider, at a 

minimum, the four statutory factors in 

mstockstill on DSK4VPTVN1PROD with PROPOSALS

11872 Federal Register / Vol. 77, No. 39 / Tuesday, February 28, 2012 / Proposed Rules 

14EPA’s Reasonable Progress Guidance, pages 

4.2–4–3. 

determining reasonable progress, but 

states have flexibility in how to take 

these factors into consideration. 

NCDAQ applied the methodology 

developed by VISTAS for identifying 

appropriate sources to be considered for 

additional controls under reasonable 

progress for the implementation period 

ending in 2018 that is addressed by this 

SIP. Using this methodology, NCDAQ 

first identified those emissions and 

emissions units most likely to have an 

impact on visibility in the State’s and 

neighboring Class I areas. Units with 

emissions of SO2 with a relative 

contribution to visibility impairment of 

at least a one percent contribution at 

any Class I area were then subject to a 

reasonable progress control analysis 

except for utilities subject to CAIR. 

After reviewing NCDAQ’s 

methodology and analyses and the 

record prepared by NCDAQ, EPA 

proposes to find North Carolina’s 

conclusion that no further controls are 

necessary at this time acceptable. EPA 

proposes to find that North Carolina 

adequately evaluated the control 

technologies available at the time of its 

analysis and applicable to this type of 

facility and consistently applied its 

criteria for reasonable compliance costs. 

The State also included appropriate 

documentation in its SIP of the 

technical analysis it used to assess the 

need for and implementation of 

reasonable progress controls. Although 

the use of a specific threshold for 

assessing costs means that a state may 

not fully consider available emissions 

reduction measures above its threshold 

that would result in meaningful 

visibility improvement, EPA believes 

that the North Carolina SIP still ensures 

reasonable progress. In proposing to 

approve North Carolina’s reasonable 

progress analysis, EPA is placing great 

weight on the fact that there is no 

indication in the SIP submittal that 

North Carolina, as a result of using a 

specific cost effectiveness threshold, 

rejected potential reasonable progress 

measures that would have had a 

meaningful impact on visibility in its 

Class I areas. EPA notes that given the 

emissions reductions resulting from 

CAIR and the measures in nearby states, 

the visibility improvements projected 

for the affected Class I areas are in 

excess of that needed to be on the 

uniform rate of progress. 

B. Facilities With Emissions Units 

Subject to CAIR Within AOI of Any 

Class I Area 

NCDAQ identified 16 EGUs at eight 

facilities which met the State’s 

minimum threshold for reasonable 

progress evaluation because they were 

modeled to fall within the SO2 AOI of 

any Class I area and have a one percent 

or greater contribution to the sulfate 

visibility impairment to at least one 

Class I area. North Carolina determined 

that no additional controls for the 

State’s EGUs for SO2 were reasonable 

during the first implementation period. 

In reaching this decision, NCDAQ 

evaluated the amount of SO2 emissions 

reductions from the EGU sector 

expected from the implementation of 

North Carolina’s CSA and CAIR. The 

EGUs in North Carolina are expected to 

reduce their SO2 emissions by greater 

than 80 percent between 2002 and 2018. 

Additionally, NCDAQ considered the 

four reasonable progress factors set forth 

in EPA’s RHR as they apply to the 

State’s entire EGU sector in sections 7.7 

and 7.8 of the North Carolina SIP. In 

particular, the State took into account 

the factors of cost and time necessary for 

compliance in view of EPA’s analysis 

supporting CAIR. 

Based on this analysis, NCDAQ 

concluded that the emissions reductions 

required by CAIR constitute reasonable 

measures for North Carolina EGUs 

during this first assessment period. This 

conclusion is bolstered by the fact that, 

as discussed in section IV.C.7, visibility 

improvement at the State’s Class I areas 

is projected to exceed the uniform rate 

of progress in this first implementation 

period. NCDAQ intends to re-evaluate 

EPA’s Integrated Planning Model (IPM) 

predictions of SO2 emissions reductions 

for CAIR at the time of the next periodic 

progress report to ensure that the 

reductions are in fact taking place where 

they were predicted. Based on the 

controls required by CSA, and predicted 

by IPM under CAIR, NCDAQ has 

concluded that, at this time, these 

existing regulatory programs constitute 

reasonable control measures for these 16 

EGUs during the first implementation 

period (between the baseline and 2018). 

EPA proposes a limited approval of 

North Carolina’s methodology and 

determination that no additional 

controls beyond CAIR and CSA are 

reasonable for SO2 for affected North 

Carolina EGUs for the first 

implementation period. 

C. Facilities With Unit(s) Found Not 

Subject to Reasonable Progress Analysis 

1. Non-EGUs Subject to BART 

Three emissions units at Blue Ridge 

Paper that met the State’s minimum 

threshold for a reasonable progress 

control evaluation are emissions units 

that NCDAQ also found to be subject to 

BART. NCDAQ concluded that the 

application of BART constitutes 

reasonable progress for these three units 

for this implementation period, and 

thus, it is not requiring any additional 

controls for reasonable progress at this 

time. As discussed in EPA’s Reasonable 

Progress Guidance, since the BART 

analysis is based, in part, on an 

assessment of many of the same factors 

that must be addressed in establishing 

the RPGs, EPA believes that it is 

reasonable to conclude that any control 

requirements imposed in the BART 

determination also satisfy the RPGrelated requirements for source review 

in the first implementation period.14

Thus, EPA proposes to concur with the 

State’s conclusions that BART satisfies 

reasonable progress for the first 

implementation period for these three 

emissions units at Blue Ridge Paper. 

2. Other Units Exempted from Preparing 

a Reasonable Progress Control Analysis 

NCDAQ did not evaluate the two 

emissions units at Ecusta Business 

Development Center since they ceased 

operation prior to the regional haze SIP 

submittal date. Two of the four units at 

PCS Phosphate in Aurora that were 

identified for assessment for reasonable 

progress have since permanently ceased 

operation and therefore were not 

evaluated further. 

6. BART 

BART is an element of North 

Carolina’s LTS for the first 

implementation period. The BART 

evaluation process consists of three 

components: (a) An identification of all 

the BART-eligible sources, (b) an 

assessment of whether the BARTeligible sources are subject to BART and 

(c) a determination of the BART 

controls. These components, as 

addressed by NCDAQ and NCDAQ’s 

findings, are discussed as follows. 

A. BART-Eligible Sources 

The first phase of a BART evaluation 

is to identify all the BART-eligible 

sources within the State’s boundaries. 

NCDAQ identified the BART-eligible 

sources in North Carolina by utilizing 

the three eligibility criteria in the BART 

Guidelines (70 FR 39158) and EPA’s 

regulations (40 CFR 51.301): (1) One or 

more emissions units at the facility fit 

within one of the 26 categories listed in 

the BART Guidelines; (2) the emissions 

units were not in operation prior to 

August 7, 1962, and were in existence 

on August 7, 1977; and (3) these units 

have the potential to emit 250 tons or 

more per year of any visibility-impairing 

pollutant. 

mstockstill on DSK4VPTVN1PROD with PROPOSALS

Federal Register / Vol. 77, No. 39 / Tuesday, February 28, 2012 / Proposed Rules 11873 

15Note that EPA’s reference to CALPUFF 

encompasses the entire CALPUFF modeling system, 

which includes the CALMET, CALPUFF, and 

CALPOST models and other pre and post 

processors. The different versions of CALPUFF 

have corresponding versions of CALMET, 

CALPOST, etc. which may not be compatible with 

previous versions (e.g., the output from a newer 

version of CALMET may not be compatible with an 

older version of CALPUFF). The different versions 

of the CALPUFF modeling system are available 

from the model developer on the following Web 

site: http://www.src.com/verio/download/ 

download.htm. 

The BART Guidelines also direct 

states to address SO2, NOX, and direct 

PM (including both PM10 and PM2.5) 

emissions as visibility-impairment 

pollutants and to exercise judgment in 

determining whether VOC or ammonia 

emissions from a source impair 

visibility in a Class I area. See 70 FR 

39160. VISTAS modeling demonstrated 

that VOC from anthropogenic sources 

and ammonia from point sources, 

except for potentially one ammonia 

source, are not significant visibilityimpairing pollutants in North Carolina, 

as discussed in section IV.C.3 of this 

action. Based on the VISTAS modeling, 

NCDAQ has determined that ammonia 

emissions from the State’s point sources 

are not anticipated to cause or 

contribute significantly to any 

impairment of visibility in Class I areas 

and should be exempt for BART 

purposes. No ammonia source in North 

Carolina was identified by VISTAS as a 

possible contributor to visibility 

impairment. 

B. BART-Subject Sources 

The second phase of the BART 

evaluation is to identify those BARTeligible sources that may reasonably be 

anticipated to cause or contribute to 

visibility impairment at any Class I area, 

i.e., those sources that are subject to 

BART. The BART Guidelines allow 

states to consider exempting some 

BART-eligible sources from further 

BART review because they may not 

reasonably be anticipated to cause or 

contribute to any visibility impairment 

in a Class I area. Consistent with the 

BART Guidelines, North Carolina 

required each of its BART-eligible 

sources to develop and submit 

dispersion modeling to assess the extent 

of their contribution to visibility 

impairment at Class I areas in 

surrounding states. 

1. Modeling Methodology 

The BART Guidelines allow states to 

use the CALPUFF 15 modeling system 

(CALPUFF) or another appropriate 

model to predict the visibility impacts 

from a single source on a Class I area 

and therefore, to determine whether an 

individual source is anticipated to cause 

or contribute to impairment of visibility 

in Class I areas, i.e., ‘‘is subject to 

BART.’’ EPA believes that CALPUFF is 

the best regulatory modeling application 

currently available for predicting a 

single source’s contribution to visibility 

impairment (70 FR 39162). North 

Carolina, in coordination with VISTAS, 

used the CALPUFF modeling system to 

determine whether individual sources 

in North Carolina were subject to BART. 

The BART Guidelines also 

recommend that states develop a 

modeling protocol for making 

individual source attributions and 

suggest that states may want to consult 

with EPA and their RPO to address any 

issues prior to modeling. The VISTAS 

states, including North Carolina, 

developed a ‘‘Protocol for the 

Application of CALPUFF for BART 

Analyses.’’ Stakeholders, including 

EPA, FLMs, industrial sources, trade 

groups, and other interested parties, 

actively participated in the development 

and review of the VISTAS protocol. 

VISTAS developed a post-processing 

approach to use the new IMPROVE 

equation with the CALPUFF model 

results so that the BART analyses could 

consider the old and new IMPROVE 

equations. North Carolina’s justification 

included a method to process the 

CALPUFF output and a rationale on the 

benefits of using the new IMPROVE 

equation. 

2. Contribution Threshold 

For states using modeling to 

determine the applicability of BART to 

single sources, the BART Guidelines 

note that the first step is to set a 

contribution threshold to assess whether 

the impact of a single source is 

sufficient to cause or contribute to 

visibility impairment at a Class I area. 

The BART Guidelines state that ‘‘[a] 

single source that is responsible for a 1.0 

deciview change or more should be 

considered to ‘cause’ visibility 

impairment.’’ The BART Guidelines 

also state that ‘‘the appropriate 

threshold for determining whether a 

source ‘contributes to visibility 

impairment’ may reasonably differ 

across states,’’ but, ‘‘[a]s a general 

matter, any threshold that you use for 

determining whether a source 

‘contributes’ to visibility impairment 

should not be higher than 0.5 

deciviews.’’ The Guidelines affirm that 

states are free to use a lower threshold 

if they conclude that the location of a 

large number of BART-eligible sources 

in proximity of a Class I area justifies 

this approach. 

North Carolina used a contribution 

threshold of 0.5 deciview for 

determining which sources are subject 

to BART. NCDAQ concluded that, 

considering the results of the visibility 

impacts modeling conducted, a 0.5 

deciview threshold was appropriate in 

this situation and a lower threshold was 

not warranted for the following reasons. 

The State demonstrated that there are a 

limited number of in and out of state 

sources that impact the Class I areas in 

the State, and that there are a limited 

number of sources in close proximity to 

each of the affected Class I areas. 

Additionally, the majority of the 

visibility impacts were well below 0.5 

deciview. Also, even though several 

sources impacted each Class I area, the 

overall impacts were low from the 

sources. EPA is proposing to agree with 

North Carolina that the overall impacts 

of these sources are not sufficient to 

warrant a lower contribution threshold 

and that a 0.5 deciview threshold was 

appropriate in this instance. 

3. Identification of Sources Subject to 

BART 

North Carolina identified 17 facilities 

with BART-eligible sources. All of 

North Carolina’s 17 BART-eligible 

sources were required by the State to 

submit exemption-modeling 

demonstrations. North Carolina found 

that two of its BART-eligible sources 

(Blue Ridge Paper and PCS Phosphate) 

had modeled visibility impacts of more 

than the State’s 0.5 deciview threshold. 

Therefore, these two facilities are 

subject to BART and submitted State 

permit applications including their 

proposed BART determinations. PCS 

Phosphate subsequently shut down its 

two sulfuric acid units subject to BART 

and these units were not further 

evaluated. 

The 15 remaining sources were able to 

demonstrate that they are not subject to 

BART by modeling less than a 0.5 

deciview visibility impact at the 

affected Class I areas. This modeling 

involved emissions of NOX, SO2, and 

PM10 as applicable to individual 

facilities. 

Six of North Carolina’s BART-eligible 

sources are facilities with EGUs that are 

subject to CAIR. As noted above, the 

RHR allows states to implement an 

alternative program in lieu of BART so 

long as the alternative program can be 

demonstrated to achieve greater 

reasonable progress toward the national 

visibility goal than would BART. Under 

regulations issued in 2005 revising the 

regional haze program, EPA made just 

such a demonstration for CAIR. See 70 

FR 39104 (July 6, 2005). EPA’s 

regulations provide that states 

participating in the CAIR cap-and trade 

program under 40 CFR part 96 pursuant 

to an EPA-approved CAIR SIP or which 

mstockstill on DSK4VPTVN1PROD with PROPOSALS

11874 Federal Register / Vol. 77, No. 39 / Tuesday, February 28, 2012 / Proposed Rules 

16EGUs were only evaluated for PM emissions. 

North Carolina relied on CAIR to satisfy BART for 

SO2 and NOX for its EGUs in CAIR, in accordance with 40 CFR 51.308(e)(4). Thus, SO2 and NOX were 

not analyzed. 

remain subject to the CAIR Federal 

Implementation Plan in 40 CFR part 97 

need not require affected BART-eligible 

EGUs to install, operate, and maintain 

BART for emissions of SO2 and NOX. 

See 40 CFR 51.308(e)(4). Because CAIR 

did not address direct emissions of PM, 

states were still required to conduct a 

BART analysis for PM emissions from 

EGUs subject to BART for that pollutant. 

Thus, North Carolina’s EGUs were 

allowed to submit BART exemption 

modeling demonstrations for PM 

emissions only. All of the BART-eligible 

EGUs demonstrated that their PM 

emissions do not contribute to visibility 

impairment in any Class I area. Table 5 

identifies the 17 BART-eligible sources 

located in North Carolina. 

TABLE 5—NORTH CAROLINA BART—ELIGIBLE AND SUBJECT-TO-BART SOURCES

Facilities With Unit(s) Subject to BART: 

Blue Ridge Paper 

Facilities With Unit(s) Not Subject to BART: 

EGU CAIR and BART Modeling (PM only) Exempt Sources 16: 

Duke Energy—Belews Creek Steam Station 

Duke Energy—Cliffside Steam Station 

Duke Energy—Marshall Steam Station 

Progress Energy—Asheville Plant 

Progress Energy—Roxboro Steam Electric Plant 

Progress Energy—Sutton Plant 

Non-EGU BART Modeling Exempt: 

Alcoa, Inc.-Badin Works 

DAK Americas—Cape Fear 

DAK Americas—Cedar Creek 

Elementis Chromium 

International Paper—Riegelwood Mill 

International Paper—Roanoke Rapids 

Invista, S.A.R.L. 

Weyerhaeuser Company—Plymouth 

Weyerhaeuser Company—New Bern 

Shut Down: 

PCS Phosphate 

Prior to the CAIR remand, the State’s 

reliance on CAIR to satisfy BART for 

NOX and SO2 for affected CAIR EGUs 

was fully approvable and in accordance 

with 40 CFR 51.308(e)(4). However, the 

BART assessments for CAIR EGUs for 

NOX and SO2 and other provisions in 

this SIP revision are based on CAIR. In 

a separate action, EPA has proposed a 

limited disapproval of the North 

Carolina regional haze SIP because of 

deficiencies in the State’s regional haze 

SIP submittal arising from the remand 

by the D.C. Circuit to EPA of CAIR. See 

76 FR 82219. Consequently, EPA is not 

taking action in this proposed 

rulemaking to address the State’s 

reliance on CAIR to meet certain 

regional haze requirements. 

C. BART Determination 

The five BART-eligible units at Blue 

Ridge Paper modeled visibility impacts 

of more than the 0.5 deciview threshold 

and are therefore subject to BART. 

Consequently, Blue Ridge Paper 

submitted to the State a permit 

application that included their proposed 

BART determination. 

In accordance with the BART 

Guidelines, to determine the level of 

control that represents BART for each 

source, the State first reviewed existing 

controls on these units to assess 

whether these constituted the best 

controls currently available, then 

identified what other technically 

feasible controls are available, and 

finally, evaluated the technically 

feasible controls using the five BART 

statutory factors. The State’s evaluations 

and conclusions, and EPA’s assessment, 

are summarized below. The units 

subject to the BART requirements at 

Blue Ridge Paper include the two 

recovery furnaces, their associated smelt 

dissolving tanks, and the black liquor 

oxidation system (BLOX). NCDAQ 

concluded that BART for all of these 

emissions sources is the existing 

emissions control systems currently in 

place. 

The recovery furnaces emit PM, SO2, 

and NOX. For the recovery furnaces, 

potential retrofit control technologies 

for PM emissions were not further 

evaluated since the units are already 

equipped with the most stringent 

controls and since the operation of these 

controls is required by the facility’s title 

V operating permit. For NOX, several 

potential control alternatives were 

evaluated; however, NCDAQ believes 

that the installation of NOX reduction 

controls for the recovery furnaces is not 

economically feasible. For SO2, 

installation of a wet scrubber following 

the ESP was identified as technically 

feasible; however, it was not considered 

economically feasible and would result 

in only a marginal visibility 

improvement at one Class I area (Great 

Smoky Mountains) and degradation in 

visibility at another (Shining Rock). 

Therefore, the State determined that 

retrofit controls are not warranted as 

BART for SO2 emissions from the 

recovery furnaces. 

The smelt dissolving tanks emit PM, 

SO2, and NOX. No NOX controls are 

available for this source type. For PM 

and SO2, the number of technically 

feasible controls is limited due to the 

fact that the emissions are minimal and 

of low velocity. Although several 

options were evaluated, they would 

only minimally reduce the number of 

days above 0.5 deciview at Shining 

Rock and Great Smoky Mountains, and 

NCDAQ believes that the installation of 

retrofit controls on the smelt dissolving 

tanks as BART is not economically 

feasible (in excess of $13,000/ton for 

less than 44 tons/year of particulate 

reduction). 

The BLOX system emits PM, SO2 and 

NOX. Blue Ridge is complying with 

MACT Subpart S through alternative 

requirements approved by the EPA 

under an equivalency by permit 

mstockstill on DSK4VPTVN1PROD with PROPOSALS

Federal Register / Vol. 77, No. 39 / Tuesday, February 28, 2012 / Proposed Rules 11875 

17Many of the CAIR states without Class I areas 

similarly relied on CAIR emissions reductions 

within the state to address some or all of their 

contribution to visibility impairment in other states’ 

Class I areas, which the impacted Class I area 

state(s) used to set the RPGs for their Class I area(s). 

Certain surrounding non-CAIR states also relied on 

reductions due to CAIR in nearby states to develop 

their regional haze SIP submittals. 

approach. Under these alternative 

requirements, Blue Ridge is controlling 

the BLOX system to achieve a greater 

level of hazardous air pollutant (HAP) 

reduction by controlling emissions from 

the BLOX system in a new Regenerative 

Thermal Oxidizer (RTO) equipped with 

a wet scrubber for SO2 control. Proper 

operation of the RTO and combustion of 

natural gas as auxiliary fuel minimize 

PM and NOX emissions. 

Because the unit is already equipped 

with the most stringent controls as 

required by the MACT standards, and 

permit limits are in place to ensure 

these controls are operated properly, the 

NCDAQ has determined that BART for 

the BLOX is existing controls. 

EPA proposes to agree with North 

Carolina’s analyses and conclusions for 

the BART emissions units located at the 

Blue Ridge Paper facility. EPA has 

reviewed the North Carolina analyses 

and proposes to conclude that they were 

conducted in a manner that is consistent 

with EPA’s BART Guidelines and EPA’s 

Air Pollution Control Cost Manual 

(http://www.epa.gov/ttncatc1/ 

products.html#cccinfo). Therefore, the 

conclusions reflect a reasonable 

application of EPA’s guidance to these 

sources. 

7. RPGs 

The RHR at 40 CFR 51.308(d)(1) 

requires states to establish RPGs for 

each Class I area within the state 

(expressed in deciviews) that provide 

for reasonable progress towards 

achieving natural visibility. VISTAS 

modeled visibility improvements under 

existing federal and state regulations for 

the period 2004–2018 and additional 

control measures which the VISTAS 

states planned to implement in the first 

implementation period. At the time of 

VISTAS modeling, some of the other 

states with sources potentially 

impacting visibility at the North 

Carolina Class I areas had not yet made 

final control determinations for BART 

and/or reasonable progress, and thus, 

these controls were not included in the 

modeling submitted by North Carolina. 

Any controls resulting from those 

determinations will provide additional 

emissions reductions and resulting 

visibility improvement, which give 

further assurances that North Carolina 

will achieve its RPGs. This modeling 

demonstrates that the 2018 base control 

scenario provides for an improvement 

in visibility better than the uniform rate 

of progress for both of the North 

Carolina Class I areas for the most 

impaired days over the period of the 

implementation plan and ensures no 

degradation in visibility for the least 

impaired days over the same period. 

On February 16, 2010, NCDAQ sent a 

letter to EPA Region 4 clarifying the 

reason for the differences in the RPGs 

for Great Smoky Mountains and Joyce 

Kilmer presented in the North Carolina 

and Tennessee regional haze SIP 

submittals. For the 20 percent worst 

days, the April 4, 2008, Tennessee 

submittal used 23.50 deciviews while 

the North Carolina submittal states the 

RPG as 23.7 (or 23.66) deciviews. 

(Similarly, for the 20 percent best days, 

the RPG differences between the two 

states’ submittals were 12.2 (or 12.15) 

deciviews in the North Carolina 

submittal vs 12.11 deciviews in the 

Tennessee submittal.) NCDAQ 

explained that the differences are due to 

different modeling runs used by each 

state. At the time of SIP development, 

only the earlier version of the VISTAS 

modeling run was available to NCDAQ. 

NCDAQ acknowledges that the RPGs in 

the Tennessee regional haze SIP 

represent the most current information 

and commits to revise the RPGs for 

Great Smoky Mountains and Joyce 

Kilmer in the periodic progress report 

SIP. In accordance with this letter of 

clarification, Table 6 below reflects the 

updated RPGs of 12.11 (approximated to 

12.1) and 23.50 for both the best and 

worst days, respectively, for these two 

Class I areas. 

As shown in Table 6 below, North 

Carolina’s RPGs for the 20 percent worst 

days provide greater visibility 

improvement by 2018 than the uniform 

rate of progress for the State’s Class I 

areas. Also, the RPGs for the 20 percent 

best days provide greater visibility 

improvement by 2018 than current best 

day conditions. The regional haze 

provisions specify that a state may not 

adopt a RPG that represents less 

visibility improvement than is expected 

to result from other CAA requirements 

during the implementation period. 40 

CFR 51.308(d)(1)(vi). Therefore, the 

CAIR states with Class I areas, like 

North Carolina, took into account 

emissions reductions anticipated from 

CAIR in determining their 2018 RPGs.17

The modeling supporting the analysis of 

these RPGs is consistent with EPA 

guidance at the time. 

TABLE 6—NORTH CAROLINA 2018 RPGS

[In deciviews] 

Class I area 

Baseline 

visibility—20% 

worst days 

2018 RPG— 

20% worst days 

(improvement 

from baseline) 

Uniform rate 

of progress at 

2018—20% 

worst days 

Baseline 

visibility— 

20% best days 

2018 RPG— 

20% best days 

(improvement 

from baseline) 

Great Smoky Mountains National Park ........... 30.3 23.5 (6.8) 25.79 13.6 12.1 (1.5) 

Joyce Kilmer-Slickrock Wilderness Area ......... 30.3 23.5 (6.8) 25.79 13.6 12.1 (1.5) 

Linville Gorge Wilderness Area ....................... 28.8 22.0 (6.8) 24.67 11.1 9.6 (1.5) 

Shining Rock Wilderness Area ........................ 28.5 22.1 (6.4) 24.50 7.7 6.9 (0.8) 

Swanquarter Wilderness Area ......................... 24.7 20.4 (4.3) 21.66 12.0 11.0 (1.0) 

The RPGs for the Class I areas in 

North Carolina are based on modeled 

projections of future conditions that 

were developed using the best available 

information at the time the analysis was 

done. These projections can be expected 

to change as additional information 

regarding future conditions becomes 

available. For example, new sources 

may be built, existing sources may shut 

down or modify production in response 

to changed economic circumstances, 

and facilities may change their 

emissions characteristics as they install 

control equipment to comply with new 

rules. It would be both impractical and 

resource-intensive to require a state to 

continually adjust its RPGs every time 

an event affecting these future 

projections changed. 

EPA recognized the problems of a 

rigid requirement to meet a long-term 

goal based on modeled projections of 

future visibility conditions and 

mstockstill on DSK4VPTVN1PROD with PROPOSALS

11876 Federal Register / Vol. 77, No. 39 / Tuesday, February 28, 2012 / Proposed Rules 

18North Carolina submitted its visibility SIP 

revisions addressing RAVI on April 15, 1985, which 

EPA approved on January 21, 1986 (51 FR 2695). 

addressed the uncertainties associated 

with RPGs in several ways. EPA made 

clear in the RHR that the RPG is not a 

mandatory standard which must be 

achieved by a particular date. See 64 FR 

35733. At the same time, EPA 

established a requirement for a 

midcourse review and, if necessary, 

correction of the states’ regional haze 

plans. See 40 CFR 52.308(g). In 

particular, the RHR calls for a five-year 

progress review after submittal of the 

initial regional haze plan. The purpose 

of this progress review is to assess the 

effectiveness of emissions management 

strategies in meeting the RPGs and to 

provide an assessment of whether 

current implementation strategies are 

sufficient for the state or affected states 

to meet their RPGs. If a state concludes, 

based on its assessment, that the RPGs 

for a Class I area will not be met, the 

RHR requires the state to take 

appropriate action. See 40 CFR 

52.308(h). The nature of the appropriate 

action will depend on the basis for the 

state’s conclusion that the current 

strategies are insufficient to meet the 

RPGs. North Carolina specifically 

committed to follow this process in its 

submittal. Accordingly, EPA proposes to 

approve North Carolina’s RPGs for Great 

Smoky Mountains, Joyce Kilmer, 

Linville Gorge, Shining Rock, and 

Swanquarter. 

D. Coordination of RAVI and Regional 

Haze Requirements 

EPA’s visibility regulations direct 

states to coordinate their RAVI LTS and 

monitoring provisions with those for 

regional haze, as explained in sections 

III.F and III.G of this action. Under 

EPA’s RAVI regulations, the RAVI 

portion of a state SIP must address any 

integral vistas identified by the FLMs 

pursuant to 40 CFR 51.304. See 40 CFR 

51.302. An integral vista is defined in 40 

CFR 51.301 as a ‘‘view perceived from 

within the mandatory Class I Federal 

area of a specific landmark or panorama 

located outside the boundary of the 

mandatory Class I Federal area.’’ 

Visibility in any mandatory Class I area 

includes any integral vista associated 

with that area. The FLMs did not 

identify any integral vistas in North 

Carolina. In addition, the Class I areas 

in North Carolina are neither 

experiencing RAVI nor are any of its 

sources affected by the RAVI provisions. 

Thus, the December 17, 2007, North 

Carolina regional haze SIP submittal 

does not explicitly address the two 

requirements regarding coordination of 

the regional haze with the RAVI LTS 

and monitoring provisions. North 

Carolina has, however, previously made 

a commitment to address RAVI should 

the FLMs certify visibility impairment 

from an individual source.18 EPA finds 

that this regional haze submittal 

appropriately supplements and 

augments North Carolina’s RAVI 

visibility provisions to address regional 

haze by updating the monitoring and 

LTS provisions as summarized below in 

this section. 

In its December 17, 2007, submittal, 

NCDAQ updated its visibility 

monitoring program and developed a 

LTS to address regional haze. Also in 

this submittal, NCDAQ affirmed its 

commitment to complete items required 

in the future under EPA’s RHR. 

Specifically, NCDAQ made a 

commitment to review and revise its 

regional haze implementation plan and 

submit a plan revision to EPA by July 

31, 2018, and every 10 years thereafter. 

See 40 CFR 51.308(f). In accordance 

with the requirements listed in 40 CFR 

51.308(g) of EPA’s regional haze 

regulations and 40 CFR 51.306(c) of the 

RAVI LTS regulations, NCDAQ 

committed to submitting a report to EPA 

on progress towards the RPGs for each 

mandatory Class I area located within 

North Carolina and for each mandatory 

Class I area located outside North 

Carolina that may be affected by 

emissions from within North Carolina. 

The progress report is required to be in 

the form of a SIP revision and is due 

every five years following the initial 

submittal of the regional haze SIP. See 

40 CFR 51.308(g). Consistent with EPA’s 

monitoring regulations for RAVI and 

regional haze, North Carolina will rely 

on the IMPROVE network for 

compliance purposes, in addition to any 

RAVI monitoring that may be needed in 

the future. See 40 CFR 51.305, 40 CFR 

51.308(d)(4). Also, the North Carolina 

new source review (NSR) rules, 

previously approved in the State’s SIP, 

continue to provide a framework for 

review and coordination with the FLMs 

on new sources and major modifications 

to existing sources subject to the NSR 

regulations which may have an adverse 

impact on visibility in either form (i.e., 

RAVI and/or regional haze) in any Class 

I area. 

E. Monitoring Strategy and Other 

Implementation Plan Requirements 

The primary monitoring network for 

regional haze in North Carolina is the 

IMPROVE network. As discussed in 

section IV.B.2 of this notice, the 

following Class I areas in North Carolina 

have IMPROVE monitoring sites: 

Linville Gorge, Shining Rock, and 

Swanquarter. There is also one 

IMPROVE site in Tennessee that serves 

as the monitoring site for both Great 

Smoky Mountains and Joyce Kilmer, 

both of which lie partly in Tennessee 

and partly in North Carolina. 

IMPROVE monitoring data from 

2000–2004 serves as the baseline for the 

regional haze program, and is relied 

upon in the December 17, 2007, regional 

haze submittal. Data produced by the 

IMPROVE monitoring network will be 

used nearly continuously for preparing 

the five-year progress reports and the 

10-year SIP revisions, each of which 

relies on analysis of the preceding five 

years of data. The Visibility Information 

Exchange Web System (VIEWS) Web 

site has been maintained by VISTAS 

and the other RPOs to provide ready 

access to the IMPROVE data and data 

analysis tools. North Carolina is 

encouraging VISTAS and the other 

RPOs to maintain the VIEWS or a 

similar data management system to 

facilitate analysis of the IMPROVE data. 

In addition to the IMPROVE 

measurements, there is long-term 

limited monitoring by FLMs which 

provides additional insight into progress 

toward regional haze goals. Such 

measurements include: 

D Web cameras operated by the 

National Park Service at Look Rock, 

Tennessee, and Purchase Knob, North 

Carolina, in Great Smoky Mountains, 

and by the U.S. Forest Service at Frying 

Pan Mountain in Shining Rock. 

D An integrating nephelometer for 

continuously measuring light scattering, 

operated by the National Park Service at 

Look Rock, Tennessee. 

• A Tapered Element Oscillating 

Microbalance for continuously 

measuring PM2.5 mass concentration, 

operated by the National Park Service at 

Look Rock, Tennessee. 

Additional haze-related 

measurements were made in North 

Carolina in 2002–2005 to better 

understand source contributions to 

PM2.5 mass and visibility. These studies 

included continuous monitoring of 

sulfate, nitrate, and carbon to better 

understand daily trends in PM2.5, 

detailed analyses of carbon collected on 

filters to identify source contributions to 

carbon, and additional analyses of 

sodium and ammonium on IMPROVE 

filter samples. While funding no longer 

exists to continue these special studies, 

VISTAS transferred the monitoring 

equipment to NCDAQ. 

In the regional haze submittal, the 

State notes that NCDAQ will continue to 

operate the following monitors to 

further the understanding of both PM2.5

as well as visibility formation and 

mstockstill on DSK4VPTVN1PROD with PROPOSALS

Federal Register / Vol. 77, No. 39 / Tuesday, February 28, 2012 / Proposed Rules 11877 

trends in North Carolina for as long as 

funds allow: 

• Continuous nitrate monitor and 

continuous sulfate monitor at the 

Millbrook monitoring site in Raleigh, 

North Carolina; 

• Continuous nitrate monitor at the 

Rockwell monitoring site in Rowan 

County, North Carolina, with a 

continuous sulfate monitor planned for 

this site as of January 2008; 

• 5400 R&P monitor for organic, total, 

and elemental carbon at the Millbrook 

site; and 

• Aethalometer (whose final location 

was yet to be determined at time of SIP 

development). 

In addition, NCDAQ and the local air 

agencies in the State operate a 

comprehensive PM2.5 network of the 

filter-based federal reference method 

monitors, continuous mass monitors, 

filter-based speciated monitors, and the 

continuous speciated monitors 

described above. 

F. Consultation With States and FLMs 

1. Consultation With Other States 

In December 2006 and May 2007, the 

State Air Directors from the VISTAS 

states held formal interstate 

consultation meetings. The purpose of 

these meetings was to discuss the 

methodology proposed by VISTAS for 

identifying sources to evaluate for 

reasonable progress. The states invited 

FLM and EPA representatives to 

participate and to provide additional 

feedback. The Directors discussed the 

results of analyses showing 

contributions to visibility impairment 

from states to each of the Class I areas 

in the VISTAS region. 

NCDAQ evaluated the impact of 

North Carolina sources on Class I areas 

in neighboring states. The state in which 

a Class I area is located is responsible 

for determining which sources, both 

inside and outside of that state, to 

evaluate for reasonable progress 

controls. Because many of these states 

had not yet defined their criteria for 

identifying sources to evaluate for 

reasonable progress, North Carolina 

applied its AOI methodology to identify 

sources in the State that have emissions 

units with impacts large enough to 

potentially warrant further evaluation 

and analysis. The State identified one 

emissions unit in North Carolina with a 

contribution of one percent or more to 

the visibility impairment at the 

following Class I area in a neighboring 

state: James River Face Wilderness Area, 

Virginia. North Carolina also identified 

two emissions units that impact the 

shared Class I areas located in both 

North Carolina and Tennessee (Great 

Smoky Mountains and Joyce Kilmer). 

Based on an evaluation of the four 

reasonable progress statutory factors, 

North Carolina determined that there 

are no additional control measures for 

these North Carolina emissions units 

that would be reasonable to implement 

to mitigate visibility impacts in the 

Class I areas in these neighboring states. 

NCDAQ consulted with these states 

regarding its reasonable progress control 

evaluations showing no cost-effective 

controls available for those emissions 

units in North Carolina contributing at 

least one percent to visibility 

impairment at Class I areas in the states. 

Additionally, NCDAQ sent letters to 

other states in the VISTAS region, 

specifically Alabama, Georgia, and 

South Carolina, documenting its 

analysis using the State’s AOI 

methodology that no SO2 emissions 

units in North Carolina contribute at 

least one percent to the visibility 

impairment at the Class I areas in those 

states. No adverse comments were 

received from the other VISTAS states. 

The documentation for these formal 

consultations is provided in Appendix J 

of North Carolina’s SIP. 

Regarding the impact of sources 

outside of the State on Class I areas in 

North Carolina, NCDAQ sent letters to 

Alabama, Delaware, Georgia, South 

Carolina, Tennessee, and Virginia 

pertaining to emissions units within 

these states that the State believes 

contributed one percent or higher to 

visibility impairment in the North 

Carolina Class I areas. At that time, 

these neighboring states were still in the 

process of evaluating BART and 

reasonable progress for their sources. 

Any controls resulting from those 

determinations will provide additional 

emissions reductions and resulting 

visibility improvement, which give 

further assurances that North Carolina 

will achieve its RPGs. Therefore, to be 

conservative, North Carolina opted not 

to rely on any additional emissions 

reductions from sources located outside 

the State’s boundaries beyond those 

already identified in the State’s regional 

haze SIP submittal and as discussed in 

section IV.C.1 of this action. 

North Carolina also received letters 

from the Mid-Atlantic/Northeast 

Visibility Union (MANE–VU) RPO 

states of Maine, New Jersey, and New 

Hampshire in early 2007 stating that 

based on MANE–VU’s analysis of 2002 

emissions data, North Carolina 

contributed to visibility impairment at 

Class I areas in those states. These 

letters invited North Carolina to 

participate in future consultation 

meetings. North Carolina sent response 

letters to these states providing 

information on the State’s CSA and 

copies of the compliance plans for two 

utilities in the State showing which 

emissions units are expected to install 

controls to meet CSA NOX and SO2

emissions caps. North Carolina 

emphasized in its response letters that 

it is important to also evaluate visibility 

impairment contributions for the year 

2018 to reflect implementation of 

programs such as CAIR and CSA. 

NCDAQ noted that based upon VISTAS’ 

analyses using 2018 emissions 

projections, no emissions units in North 

Carolina meet NCDAQ’s minimum 

threshold for a reasonable progress 

control evaluation for the Class I areas 

in these states. Thus, NCDAQ stated that 

it does not believe any of its emissions 

units provide significant contributions 

from sulfate-derived visibility impacts 

to these MANE–VU states’ Class I areas, 

and expressed the State’s willingness to 

participate in future consultations 

through VISTAS. 

In their consultation discussions, the 

MANE–VU states identified twelve 

EGUs in North Carolina that they would 

like to see controlled to 90 percent 

efficiency. They also requested a control 

strategy to provide a 28 percent 

reduction in SO2 emissions from 

sources other than EGUs that would be 

equivalent to their low sulfur fuel oil 

strategy. North Carolina has controlled 

or is expecting to control under the 

North Carolina CSA eleven of the twelve 

identified EGUs. Additionally, 

scrubbers are expected on three EGUs 

that were not identified by MANE–VU. 

NCDAQ believes that these reductions 

satisfy MANE–VU’s request. 

EPA proposes to find that North 

Carolina has adequately addressed the 

consultation requirements in the RHR 

and appropriately documented its 

consultation with other states in its SIP 

submittal. 

2. Consultation With the FLMs 

Through the VISTAS RPO, North 

Carolina and the nine other member 

states worked extensively with the 

FLMs from the U.S. Departments of the 

Interior and Agriculture to develop 

technical analyses that support the 

regional haze SIPs for the VISTAS 

states. The proposed regional haze plan 

for North Carolina was out for FLM and 

EPA discussions from August to 

September 2007. North Carolina 

subsequently modified the plan to 

address comments received on this 

initial version and reissued it for public 

comment from October to November 

2007. 

Regarding North Carolina’s initial 

August 2, 2007, draft regional haze SIP 

and the proposed regional haze SIP 

mstockstill on DSK4VPTVN1PROD with PROPOSALS

11878 Federal Register / Vol. 77, No. 39 / Tuesday, February 28, 2012 / Proposed Rules 

released for public comment on October 

12, 2007, the FLMs requested that the 

State provide more information in the 

SIP revision regarding two facilities, 

Blue Ridge Paper and PCS PhosphateAurora. Based on the Blue Ridge Paper’s 

visibility impacts at multiple Class I 

areas, the FLMs asked the State to 

describe a plan to consult with the 

company on potential control actions 

prior to 2018 that may warrant a higher 

cost of control for reasonable progress. 

For PCS Phosphate, the FLMs expressed 

concern that the facility’s BART 

determination for this facility did not 

fully evaluate the effectiveness and 

associated cost of controls. Other 

comments asked for clarification of 

items and for more discussion with 

specific source information for the AOI 

reasonable progress evaluations in the 

main body of the SIP, in addition to the 

appendices. North Carolina provided 

responses to the FLMs regarding their 

comments on the draft SIP. The State 

included more of the detailed 

reasonable progress control evaluation 

information in the main body of the SIP. 

Regarding Blue Ridge Paper, the State 

described that it acknowledged in the 

SIP that the company has visibility 

impacts on multiple Class I areas and 

has notified the company that although 

additional controls are not being 

required this implementation period, 

future periods may require controls. 

NCDAQ stated in the SIP that it is 

committed to work with the company 

over the next implementation period 

and encourage the company to 

modernize some of its processes with 

more efficient, less polluting equipment. 

For the two BART-eligible units at PCS 

Phosphate, the State noted that the 

facility is planning to shut down these 

units, and thus, it would not be prudent 

to install controls on them. For the two 

units subject to a reasonable progress 

control analysis, NCDAQ included 

additional language in the SIP stating 

that it has notified the company that 

although additional controls are not 

being required this period, future 

implementation periods may require 

controls to be installed. 

To address the requirement for 

continuing consultation procedures 

with the FLMs under 40 CFR 

51.308(i)(4), NCDAQ made a 

commitment in the SIP to ongoing 

consultation with the FLMs on regional 

haze issues throughout implementation 

of its plan, including annual discussions 

of the implementation process and the 

most recent data from IMPROVE 

monitoring and VIEWS. NCDAQ also 

affirms in the SIP that FLM consultation 

is required for those sources subject to 

the State’s NSR regulations. 

G. Periodic SIP Revisions and Five-Year 

Progress Reports 

As also summarized in section IV.D of 

this notice, consistent with 40 CFR 

51.308(g), NCDAQ affirmed its 

commitment to submitting a progress 

report in the form of a SIP revision to 

EPA every five years following this 

initial submittal of the North Carolina 

regional haze SIP. The report will 

evaluate the progress made towards the 

RPGs for each mandatory Class I area 

located within North Carolina and for 

each mandatory Class I area located 

outside North Carolina that may be 

affected by emissions from within North 

Carolina. North Carolina also offered 

recommendations for several technical 

improvements that, as funding allows, 

can support the State’s next LTS. These 

recommendations are discussed in 

detail in the North Carolina submittal in 

Appendix K. 

If another state’s regional haze SIP 

identifies that North Carolina’s SIP 

needs to be supplemented or modified, 

and if after appropriate consultation 

North Carolina agrees, today’s action 

may be revisited, or additional 

information and/or changes will be 

addressed in the five-year progress 

report SIP revision. 

V. What Action is EPA Proposing? 

EPA is proposing a limited approval 

of a revision to the North Carolina SIP 

submitted by the State of North Carolina 

on December 17, 2007, as meeting some 

of the applicable regional haze 

requirements as set forth in sections 

169A and 169B of the CAA and in 40 

CFR 51.300–308, as described 

previously in this action. 

VI. Statutory and Executive Order 

Reviews 

A. Executive Order 12866, Regulatory 

Planning and Review 

The Office of Management and Budget 

(OMB) has exempted this regulatory 

action from Executive Order 12866, 

entitled ‘‘Regulatory Planning and 

Review.’’ 

B. Paperwork Reduction Act 

Under the Paperwork Reduction Act, 

44 U.S.C. 3501 et seq., OMB must 

approve all ‘‘collections of information’’ 

by EPA. The Act defines ‘‘collection of 

information’’ as a requirement for 

answers to * * * identical reporting or 

recordkeeping requirements imposed on 

ten or more persons * * *. 44 U.S.C. 

3502(3)(A). The Paperwork Reduction 

Act does not apply to this action. 

C. Regulatory Flexibility Act (RFA) 

The RFA generally requires an agency 

to conduct a regulatory flexibility 

analysis of any rule subject to notice 

and comment rulemaking requirements 

unless the agency certifies that the rule 

will not have a significant economic 

impact on a substantial number of small 

entities. Small entities include small 

businesses, small not-for-profit 

enterprises, and small governmental 

jurisdictions. 

This rule will not have a significant 

impact on a substantial number of small 

entities because SIP approvals under 

section 110 and subchapter I, part D of 

the CAA do not create any new 

requirements but simply approve 

requirements that the state is already 

imposing. Therefore, because the federal 

SIP approval does not create any new 

requirements, I certify that this action 

will not have a significant economic 

impact on a substantial number of small 

entities. 

Moreover, due to the nature of the 

federal-state relationship under the 

CAA, preparation of a flexibility 

analysis would constitute federal 

inquiry into the economic 

reasonableness of state action. The CAA 

forbids EPA to base its actions 

concerning SIPs on such grounds. 

Union Electric Co., v. EPA, 427 U.S. 

246, 255–66 (1976); 42 U.S.C. 

7410(a)(2). 

D. Unfunded Mandates Reform Act 

(UMRA) 

Under sections 202 of the Unfunded 

Mandates Reform Act of 1995 

(‘‘Unfunded Mandates Act’’), signed 

into law on March 22, 1995, EPA must 

prepare a budgetary impact statement to 

accompany any proposed or final rule 

that includes a federal mandate that 

may result in estimated costs to State, 

local, or tribal governments in the 

aggregate, or to the private sector, of 

$100 million or more. Under section 

205, EPA must select the most costeffective and least burdensome 

alternative that achieves the objectives 

of the rule and is consistent with 

statutory requirements. Section 203 

requires EPA to establish a plan for 

informing and advising any small 

governments that may be significantly 

or uniquely impacted by the rule. 

EPA has determined that today’s 

proposal does not include a federal 

mandate that may result in estimated 

costs of $100 million or more to either 

state, local, or tribal governments in the 

aggregate, or to the private sector. This 

federal action proposes to approve preexisting requirements under state or 

local law, and imposes no new 

mstockstill on DSK4VPTVN1PROD with PROPOSALS

Federal Register / Vol. 77, No. 39 / Tuesday, February 28, 2012 / Proposed Rules 11879 

requirements. Accordingly, no 

additional costs to state, local, or tribal 

governments, or to the private sector, 

result from this action. 

E. Executive Order 13132, Federalism 

Federalism (64 FR 43255, August 10, 

1999) revokes and replaces Executive 

Orders 12612 (Federalism) and 12875 

(Enhancing the Intergovernmental 

Partnership). Executive Order 13132 

requires EPA to develop an accountable 

process to ensure ‘‘meaningful and 

timely input by State and local officials 

in the development of regulatory 

policies that have federalism 

implications.’’ ‘‘Policies that have 

federalism implications’’ is defined in 

the Executive Order to include 

regulations that 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.’’ Under 

Executive Order 13132, EPA may not 

issue a regulation that has federalism 

implications, that imposes substantial 

direct compliance costs, and that is not 

required by statute, unless the federal 

government provides the funds 

necessary to pay the direct compliance 

costs incurred by state and local 

governments, or EPA consults with state 

and local officials early in the process 

of developing the proposed regulation. 

EPA also may not issue a regulation that 

has federalism implications and that 

preempts state law unless the Agency 

consults with state and local officials 

early in the process of developing the 

proposed regulation. 

This rule 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, as specified in 

Executive Order 13132, because it 

merely approves a state rule 

implementing a federal standard, and 

does not alter the relationship or the 

distribution of power and 

responsibilities established in the CAA. 

Thus, the requirements of section 6 of 

the Executive Order do not apply to this 

rule. 

F. Executive Order 13175, Coordination 

With Indian Tribal Governments 

Executive Order 13175, entitled 

‘‘Consultation and Coordination with 

Indian Tribal Governments’’ (65 FR 

67249, November 9, 2000), requires EPA 

to develop an accountable process to 

ensure ‘‘meaningful and timely input by 

tribal officials in the development of 

regulatory policies that have tribal 

implications.’’ This proposed rule does 

not have tribal implications, as specified 

in Executive Order 13175. It will not 

have substantial direct effects on tribal 

governments. Thus, Executive Order 

13175 does not apply to this rule. EPA 

specifically solicits additional comment 

on this proposed rule from tribal 

officials. 

G. Executive Order 13045, Protection of 

Children From Environmental Health 

Risks and Safety Risks 

Protection of Children from 

Environmental Health Risks and Safety 

Risks (62 FR 19885, April 23, 1997), 

applies to any rule that: (1) Is 

determined to be ‘‘economically 

significant’’ as defined under Executive 

Order 12866, and (2) concerns an 

environmental health or safety risk that 

EPA has reason to believe may have a 

disproportionate effect on children. If 

the regulatory action meets both criteria, 

the Agency must evaluate the 

environmental health or safety effects of 

the planned rule on children, and 

explain why the planned regulation is 

preferable to other potentially effective 

and reasonably feasible alternatives 

considered by the Agency. 

This rule is not subject to Executive 

Order 13045 because it does not involve 

decisions intended to mitigate 

environmental health or safety risks. 

H. Executive Order 13211, Actions That 

Significantly Affect Energy Supply, 

Distribution, or Use 

This rule is not subject to Executive 

Order 13211, ‘‘Actions Concerning 

Regulations That Significantly Affect 

Energy Supply, Distribution, or Use’’ (66 

FR 28355, May 22, 2001) because it is 

not a significant regulatory action under 

Executive Order 12866. 

I. National Technology Transfer and 

Advancement Act (NTTAA) 

Section 12 of the NTTAA of 1995 

requires federal agencies to evaluate 

existing technical standards when 

developing a new regulation. To comply 

with NTTAA, EPA must consider and 

use ‘‘voluntary consensus standards’’ 

(VCS) if available and applicable when 

developing programs and policies 

unless doing so would be inconsistent 

with applicable law or otherwise 

impractical. 

EPA believes that VCS are 

inapplicable to this action. Today’s 

action does not require the public to 

perform activities conducive to the use 

of VCS. 

List of Subjects in 40 CFR Part 52 

Environmental protection, Air 

pollution control, Intergovernmental 

relations, Nitrogen oxides, Particulate 

matter, Reporting and recordkeeping 

requirements, Sulfur dioxide, Volatile 

organic compounds. 

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

Dated: February 15, 2012. 

A. Stanley Meiburg, 

Acting Regional Administrator, Region 4. 

[FR Doc. 2012–4711 Filed 2–27–12; 8:45 am] 

BILLING CODE 6560–50–P 

ENVIRONMENTAL PROTECTION 

AGENCY 

40 CFR Part 52 

[EPA–R04–OAR–2009–0784, FRL–9638–4] 

Approval and Promulgation of Air 

Quality Implementation Plans; State of 

Mississippi; Regional Haze State 

Implementation Plan 

AGENCY: Environmental Protection 

Agency (EPA). 

ACTION: Proposed rule. 

SUMMARY: EPA is proposing a limited 

approval of two revisions to the 

Mississippi state implementation plan 

(SIP) submitted by the State of 

Mississippi through the Mississippi 

Department of Environmental Quality 

(MDEQ) on September 22, 2008, and 

May 9, 2011, that address regional haze 

for the first implementation period. 

These revisions address the 

requirements of the Clean Air Act (CAA 

or Act) and EPA’s rules that require 

states to prevent any future and remedy 

any existing anthropogenic impairment 

of visibility in mandatory Class I areas 

(national parks and wilderness areas) 

caused by emissions of air pollutants 

from numerous sources located over a 

wide geographic area (also referred to as 

the ‘‘regional haze program’’). States are 

required to assure reasonable progress 

toward the national goal of achieving 

natural visibility conditions in Class I 

areas. EPA is proposing a limited 

approval of these SIP revisions to 

implement the regional haze 

requirements for Mississippi on the 

basis that the revisions, as a whole, 

strengthen the Mississippi SIP. EPA has 

previously proposed a limited 

disapproval of the Mississippi regional 

haze SIP because of deficiencies in the 

State’s regional haze SIP submittal 

arising from the remand by the U.S. 

Court of Appeals for the District of 

Columbia Circuit (D.C. Circuit) to EPA 

of the Clean Air Interstate Rule (CAIR). 

Consequently, EPA is not proposing to 

take action in this rulemaking to address 

the State’s reliance on CAIR to meet 

certain regional haze requirements. 

mstockstill on DSK4VPTVN1PROD with PROPOSALS