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Technical Support Document for the Modeling Portions of the State of West Virginia’s 

Regional Haze State Implementation Plan (SIP) 

Entitled “West Virginia Regional Haze

State Implementation Plan to Preserve, Protect and Improve

Visibility in Class I Federal Areas

Final

June 2008”

TSD Prepared February, 2011

Todd A. Ellsworth

Office of Air Monitoring and Analysis, 3AP40

U.S. Environmental Protection Agency, Region 3

1650 Arch Street

Philadelphia, Pennsylvania 19103

______________________/s/______________________

Reviewed by Walter Wilkie, Associate Director,

Office of Air Monitoring and Analysis (3AP40)

_________3/11/2011________

Date Signed
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Technical Support Document for the Modeling Portions of the 

State of West Virginia’s Regional Haze State Implementation Plan 

(SIP) Entitled “West Virginia Regional Haze

State Implementation Plan to Preserve, Protect and Improve

Visibility in Class I Federal Areas

Final

June 2008”

Purpose of the Technical Support Document

This Technical Support Document (TSD) describes the Environmental Protection 

Agency’s (EPA’s) evaluation of the modeling portions of West Virginia’s State 

Implementation Plan (SIP) revision entitled “West Virginia Regional Haze State 

Implementation Plan to Preserve, Protect and Improve Visibility in Class I Federal 

Areas Final June 2008”. This SIP revision will hereafter be referred to as the West 

Virginia (WV) Haze SIP.

The purpose of this TSD is to provide more detailed information than can be contained in 

the official notice published in the Federal Register. Readers who need more information 

than we provide in this TSD or want to review the modeling in more detail should read 

the above referenced West Virginia Haze SIP. 

The Regulatory Framework

In section 169A(a)(1) of the 1977 Amendments to the CAA, Congress created a program 

for protecting visibility in the nation’s national parks and wilderness areas. This section 

of the CAA establishes as a national goal the “prevention of any future, and the 

remedying of any existing, impairment of visibility in mandatory Class I Federal areas1

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” (RAVI). See 45 FR 80084. These regulations 

 

1Areas designated as mandatory Class I Federal areas consist of national parks exceeding 6000 acres, 

wilderness areas and national memorial parks exceeding 5000 acres, and all international parks that were in 

existence on August 7, 1977 (42 U.S.C. 7472(a)). In accordance with section 169A of the CAA, EPA, in 

consultation with the Department of Interior, promulgated a list of 156 areas where visibility is identified as 

an important value (see 44 FR 69122, November 30, 1979). The extent of a mandatory Class I area includes 

subsequent changes in boundaries, such as park expansions (42 U.S.C. 7472(a)). Although states and tribes 

may designate as Class I additional areas which they consider to have visibility as an important value, the 

requirements of the visibility program set forth in section 169A of the CAA apply only to ‘‘mandatory 

Class I Federal areas.” Each mandatory Class I Federal area is the responsibility of a ‘‘Federal Land 

Manager’’ (FLM). (42 U.S.C. 7602(i)) 
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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 (see 64 FR 35713), the 

Regional Haze Rule (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. 

The RHR addressed the combined visibility effects of various pollution sources over a 

wide geographic region. 40 CFR 51.308(b) requires states to submit the first 

implementation plan addressing regional haze visibility impairment no later than 

December 17, 2007. Consequently, all 50 states, including those without Class I areas, 

Washington, D.C., and the Virgin Islands, are required to submit Regional Haze SIPs2.

The USEPA designated five Regional Planning Organizations (RPOs) to assist with the 

coordination and cooperation needed to address the visibility issue. West Virginia is 

among those states that make up the southeastern portion of the contiguous United States 

known as VISTAS (Visibility Improvement – State and Tribal Association of the 

Southeast), and includes the eastern band of the Cherokee Indians in addition to the 

following states: Alabama, Florida, Georgia, Kentucky, Mississippi, North Carolina, 

South Carolina, Tennessee, and Virginia (See Figure 1). Studies show that West Virginia 

significantly contributes visibility impairment in the following Class I areas: Dolly Sods 

Wilderness Area, Otter Creek Wilderness Area, James River Face Wilderness Area, 

Linville Gorge Wilderness Area, and Shenandoah National Park. With the help of the 

Visibility Improvement - State and Tribal Association of the Southeast (VISTAS) RPO, 

West Virginia has developed a SIP to address visibility impairment in all of these Class I 

Federal Areas. Figure 2 shows the 18 mandatory Federal Class I areas in the VISTAS 

Region. 

 

2Albuquerque/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).
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Figure 1. Geographical Areas of Regional Planning Organizations

 

 

Figure 2. Class I Areas in the VISTAS Region 

 
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Introduction to West Virginia’s Visibility State Implementation Plan 

EPA promulgated a rule to address regional haze on July 1, 1999 (see 64 FR 35713), the 

RHR. The RHR addressed the combined visibility effects of various pollution sources 

over a wide geographic region. 40 CFR 51.308(b) requires states to submit the first 

implementation plan addressing regional haze visibility impairment no later than 

December 17, 2007.

This SIP was developed based on consultations and work-products of the VISTAS Regional 

Planning Organization (RPO). It encompasses 1) monitoring strategies for evaluating 

visibility impacts, 2) baselines and trends, 3) long-term strategies (LTS), 4) how West 

Virginia meets its fair share of the “reasonable progress goals” (RPG) towards reducing 

visibility impairment in Class I areas, and 5) Best Available Retrofit Technology (BART). 

VISTAS states agreed upon a ≥ 1 percent sulfate attribution to a Class I area in order for an 

upwind state to meet the definition of “significantly contributing” to visibility impairment for 

that Class I area. Studies show that West Virginia significantly contributes visibility 

impairment in the following Class I areas: Dolly Sods Wilderness Area, Otter Creek 

Wilderness Area, James River Face Wilderness Area, Linville Gorge Wilderness Area, 

and Shenandoah National Park. Therefore, this SIP focuses on how West Virginia’s control 

measures will improve visibility in these areas. 

The West Virginia Division of Air Quality (WVDAQ) believes their Haze SIP demonstrates 

that West Virginia has met its BART, RPG and LTS obligations for the first visibility 

impairment planning period through existing West Virginia/Federal regulations and on-thebooks/on-the-way federal emission controls. In addition to extensive consultation with the 

VISTAS states, West Virginia has consulted with Federal Land Managers (FLMs) 

responsible for the Class I areas, and the EPA in the development of this SIP.

What Are The Components Of A Modeled Regional Haze

Demonstration?

Modeling Process Overview 

The goal of the regional haze program is to return to natural conditions by 2064, and

States are required to demonstrate, by the end of the first planning period ( by 2018), 

reasonable progress toward meeting that goal. 

West Virginia is a member of the VISTAS RPO. The VISTAS RPO was tasked with the 

assignment of preparing a PM2.5 modeling platform that all member states could use to 

model their LTSs to demonstrate reasonable progress by 2018 in meeting the ultimate 

goal of natural visibility conditions by 2064. 

The regional haze modeling was coordinated by the Southeast Regional Planning 

Organization, Visibility Improvement State and Tribal Association of the Southeast 

(VISTAS), which is comprised of the ten Southeast States (Alabama, Florida, Georgia, 

Kentucky, Mississippi, North Carolina, South Carolina, Tennessee, Virginia and West 

Virginia) and the local programs and tribal agencies located within these states. VISTAS 

contracted with Environ International Corp, Alpine Geophysics, LLC and the University 
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of California Riverside to perform the emissions and air quality modeling for this 

regional haze state and tribal implementation plans.

 

The VISTAS RPO used the Community Multi-scale Air Quality model (CMAQ) version 

4.5.1 as its photochemical grid model. The model uses simulations of chemical reactions, 

emission of PM2.5 and PM2.5 precursors and a sophisticated meteorological model (The 

Pennsylvania State University/National Center for Atmospheric Research Mesoscale

Meteorological Model (MM5)) to produce speciated PM2.5 concentrations over the 

eastern United States. The meteorological data used in the meteorological model was for 

the 2002 base year. The photochemical grid model was run with the base year

meteorology and base year emissions to determine if the model performance was

satisfactory. Once the model performance was determined to be adequate, PM 2.5

concentrations were modeled by running the model with projected emissions for 2009 

and 2018 and the original 2002 meteorology. The meteorology was held constant so that 

the results of changing the emissions would not be influenced by changing meteorology.

The EPA modeling guidance3recommends that modeling be used to develop relative 

response factors for each of 6 components of particulate matter between a base period 

(2000-2004) and a future 5-year period which will be reviewed in 2018. PM components 

used for regional haze-related applications are:

- mass associated with sulfates;

- mass associated with nitrates;

- mass associated with organic carbon;

- mass associated with elemental carbon;

- mass associated with fine soil (i.e., crustal material);

- mass associated with coarse particulate matter (i.e., PM10 - PM2.5).

Current speciated measurements in a Class I area are used in an empirically derived

equation to estimate light extinction for each day with measurements. Days are ranked

according to their resulting light extinction (measured in deciviews). This ranking is used 

to identify the 20% of days with worst and 20% of days with best visibility during each 

year in the base period. The 20% worst and best days are examined to estimate 

appropriate observed concentrations for the components of PM on “best” and “worst” 

days. Observed component concentrations are multiplied by the corresponding relative

response factors to estimate future concentrations for each component on “best” and 

“worst” days. Future component concentrations are then inserted into the equation 

relating light extinction to concentrations of particulate matter. The resulting estimates 

for future light extinction on “best” and “worst” days are compared with observations 

made during the base period to assess the future year visibility improvement and 

demonstrate reasonable progress by 2018 in meeting the ultimate goal of natural visibility

conditions by 2064. 

 

 

3 Guidance on the Use of Models and Other Analyses for Demonstrating Attainment of Air Quality Goals 

for Ozone, PM2.5, and Regional Haze, EPA -454/B-07-002, April 2007
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Steps Required in Modeling Future Year Visibility Improvement

The modeling guidance lists nine steps for preparing modeling to demonstrate reasonable 

progress toward visibility improvement goals. 

1. Develop a conceptual description of the problem to be addressed.

2. Select an appropriate model to support the demonstration.

3. Select appropriate meteorological time periods to model.

4. Choose an appropriate area to model with appropriate horizontal/vertical resolution 

and establish the initial and boundary conditions that are suitable for the application.

5. Generate meteorological inputs to the air quality model.

6. Generate emissions inputs to the air quality model.

7. Run the air quality model with base case emissions and evaluate the performance.

 Perform diagnostic tests to improve the model, as necessary.

8. Perform future year modeling (including additional control strategies, if necessary) and

 use the results to calculate future year visibility and visibility improvement.

How Did West Virginia Address All Of The Components a 

Modeled Demonstration Of Future Year Visibility Improvement?

The West Virginia Haze SIP addresses each of the required elements of a modeling 

analysis used to predict visibility improvement that is expected by 2018. 

Conceptual Description of the Problem

A conceptual model describes how weather patterns affect the formation and transport of 

PM2.5, accounting for emissions and photochemistry.

The conceptual model for the West Virginia PM2.5 SIP is described in Appendix B of the 

WV Haze SIP. Air Resources Specialists, Inc (ARS) was contracted by VISTAS to 

develop a conceptual description of the current visibility in the VISTAS area as it relates 

to meteorology and source distribution. This document was prepared in accordance with 

EPA guidance. 

Ammonium sulfate is the largest contributor to visibility impairment on the 20% haziest

days in the baseline 2000-2004 period (69-74%) at all the IMPROVE sites in the 

VISTAS region except Everglades National Park in Florida, where Ammonium sulfate is 

a close second to Particulate Organic Material ( POM) (40 and 45%, respectively). 

Particulate Organic Material (also referred to as organic carbon) is the second largest 

contributor to aerosol extinction at all other sites, contributing to between 13 and 18% of 

aerosol extinction on the worst days. Baseline conditions for 20% worst days at the 

inland sites (182.2 - 241.4 Mm-1) average higher WV Regional Haze SIP Appendix B.1 

– 494 3- 18 than conditions measured at the coastal sites (116.4 - 147.3 Mm-1).

Ammonium sulfate is also the largest contributor to visibility impairment on the 20% best

days (45-59%), with large contributions from ammonium nitrate (9-21%) POM (11-

19%). Sea salt is not a factor on the 20% worst days, but for the 20% best days it 

contributes to between 2 and 7% of the aerosol extinction at the VISTAS coastal sites.

Ammonium sulfate, Coarse Mass(CM) and POM are the largest contributors to total mass 

on the 20% best and worst days. CM, although it is a factor for total mass, has a low 

extinction efficiency and does not contribute significantly to aerosol extinction. 
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Ammonium sulfate contributes more significantly to aerosol extinction because it readily 

absorbs water vapor in the air. 

For most inland sites, the 20% haziest days are most likely to occur in the summer, and

the 20% best days occur most frequently during the winter. For coastal sites, the 20%

haziest days can occur year round, with the summer days being dominated by ammonium 

sulfate, while the worst days that occur between October and February have large 

contributions from ammonium sulfate, POM and sometimes ammonium nitrate

Sulfate is the key particle constituent from the standpoint of designing control strategies 

to improve visibility conditions in the VISTAS states. Significant further reductions in 

ambient sulfate levels are achievable, though they will require more than proportional 

reductions in SO2 emissions.

Modeling Platform

Currently one regional-scale air quality models has been evaluated and used by VISTAS

to perform air quality simulations. This is the Community Multi-scale Air Quality

modeling system (CMAQ; Byun and Ching, 1999). CMAQ was developed by USEPA. 

CMAQ has undergone extensive community development and peer review (Amar et al., 

2005) and has been successfully used in a number of regional air quality studies (Bell and 

Ellis, 2003; Hogrefe et al., 2004; Jimenez and Baldasano, 2004; Mao and Talbot, 2003; 

Mebust et al., 2003). 

Modeling for regional haze was performed by VISTAS for the ten Southeastern states, 

including West Virginia. The sections below outline the methods and inputs used by

VISTAS for the regional modeling. Additional details are provided in Appendices C, D 

and M of the WV Haze SIP.

Meteorological Time Periods Used in the Modeling

VISTAS selected all days in the year 2002 as the modeling time period for this 

demonstration. Meteorological inputs were developed for 2002 using the meteorological 

model. Emissions inventories were also developed for 2002 and processed through the 

emissions model. These inputs were then used in the air quality model to predict fine 

particle mass and visibility. The 2002 base year represents the baseline period from 2000 

to 2004. CMAQ simulations were performed for the 2002 Base Case, 2009 and 2018 

Base Case, and 2009 and 2018 Control Case. All scenarios adopt the same 

meteorological field (2002) and boundary conditions, varying only emission inputs. 

Meteorological Data Used in the Air Quality Model

The VISTAS states decided to use a prognostic meteorological model that provides lifelike meteorological inputs to the photochemical grid model. The Pennsylvania State 

University/National Center for Atmospheric Research Mesoscale Meteorological Model 

(MM5) version 3.6 was chosen for the modeling analysis. The MM5 model provides a 

reasonable representation of weather conditions at the surface and aloft. 
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Domain of the Model, Horizontal/Vertical Resolution and the Initial and Boundary 

Conditions

VISTAS has adopted the Inter-RPO domain description for its modeling runs. 

This 36-km domain covers the continental United States, southern Canada and northern

Mexico. The dimensions of this domain are 145 and 102 cells in the east-west and northsouth directions, respectively (see Figure 3). To achieve finer spatial resolution in the 

VISTAS states, a one-way nested high resolution (12-km grid resolution) was used. 

Figure 4 shows the 12-km grid, modeling domain for the VISTAS region. This is the 

modeling domain for which the reasonable progress goals are assessed. 

Figure 3. The MM5 horizontal domain is the outer most, blue grid, with the CMAQ 

36-km domain nested in the MM5 
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Figure 4. A More Detailed View of the 12-km Grid Over the VISTAS Region

 

Vertical resolution is the number of layers and the size of each layer in the model. The

layers in the photochemical grid model were set up to be compatible with the model that 

produced meteorological conditions for the photochemical grid model. The vertical 

resolution used in the modeling exercise followed EPA’s modeling guidance and

therefore adequately represents the atmosphere where PM2.5 and its precursors are

emitted and transported. 

Baseline and Future Year Emission Inventories for Modeling 

Section 51.308(d)(3)(iii) of EPA’s Regional Haze Rule requires the States to identify the 

baseline emission inventory on which strategies are based. The baseline inventory is 

intended to be used to assess progress in making emission reductions. Based on EPA 

guidance entitled, 2002 Base Year Emission Inventory SIP Planning: 8-hour Ozone, PM 

2.5, and Regional Haze Programs, which identifies 2002 as the anticipated baseline 

emission inventory year for regional haze, VISTAS and the State of West Virginia are 

using 2002 as the baseline year. Future year inventories were developed for 2009 and 

2018 based on the 2002 base year. The future year emission inventory include emissions 

growth due to projected increases in economic activity as well as the emissions 

reductions due to the implementation of control measures. 

The 2002 emissions were first generated by the individual states in the VISTAS area. The 

VISTAS contractor generated the future year emissions inventories for 2009 and 2018 for
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the regional haze modeling. The 2002 emissions from non-VISTAS areas within the 

modeling domain were obtained from other Regional Planning Organizations for their 

corresponding areas. These Regional Planning Organizations included the MidAtlantic/Northeast Visibility Union, the Midwest Regional Planning Organization and the 

Central Regional Air Planning Association. 

The complete inventory and discussion of the methodology is contained in Appendix D 

of the West Virginia Haze SIP.

Model Performance Evaluation

VISTAS CMAQ modeling was conducted for year 2002 CMAQ Performance for PM 2.5 

species and visibility was examined based on this CMAQ run on a 12 km resolution domain. 

Measurements from IMPROVE and STN networks were paired with model predictions by 

location and time for evaluation. The goal and the criteria for PM2.5 evaluation suggested by 

Boylan and Baker (2004) were adopted by every RPO for SIP modeling. The performance 

goals are: Mean Fractional Error (MFE) ≤ +50%, and Mean Fraction Bias (MFB) ≤ ±30%; 

while the criteria are proposed as: MFE ≤ +75%, and MFB ≤ ±60%. CMAQ prediction of 

PM2.5 species from STN sites and IMPROVE sites within the VISTAS Region were paired

with measurements and statistically analyzed to generate MFE and MFB values. Considering 

CMAQ performance in terms of MFE and MFB goals, sulfate, nitrate, OC, EC, and PM2.5 all 

had the majority of data points within the goal curve, some were between the goal and 

acceptable criteria, and only a few were outside the criteria curve. Only fine soil has the 

majority of points outside the criteria curve, but there were some sites still within the goal. 

For the VISTAS region, CMAQ performs best for PM2.5 sulfate, followed by PM2.5, EC, 

nitrate, OC, and then fine soil. Regional haze modeling also requires CMAQ performance 

evaluation for aerosol extinction coefficient (Bext) and the haze index. Modeled daily aerosol 

extinction at each improve site was calculated following the IMPROVE formula with 

modeled daily PM2.5 species concentration and relative humidity factors from IMPROVE. 

The approach used natural background visibility estimates and the haze index following EPA 

Guidance. The modeled Bext showed a near 1:1 linear relationship with IMPROVE observed 

Bext. 

Overall, WVDAQ found model performance to fall within acceptable limits. The 

WVDAQ further asserts that the one atmosphere modeling performed by the VISTAS 

contractors is representative of conditions in the southeastern states and is applicable for 

use in setting reasonable progress goals for the Class I areas.

Uniform Rate of Progress Goals

The key difference between SIPs from States with Class I areas and those States without 

Class I areas, but may have sources that impact visibility on Class I areas, is the 

calculation of the baseline and natural visibility for their Class I areas and the 

determination of uniform rate of progress goals - expressed in deciviews - that provide 

for reasonable progress towards achieving natural visibility by 2064. It is the Class I

states responsibility assess these calculations. The Class I States must also consult with 

those States, which may reasonably be anticipated to cause or contribute to visibility

impairment in their Class I areas (40 CFR 51.308 (d)(1)(i-vi)). 
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The baseline visibility conditions are calculated for the baseline period between 2002 and 

2004. The average impairment for the 20 most and 20 least impaired days are determined 

for each calendar year and compiled into the average of three annual averages (40 CFR 

51.308 (d)(2)(i)). The natural visibility conditions are determined for the same baseline 

period with the most and least impaired days determined by available monitoring data or 

an appropriate data analysis technique (40 CFR 51.308 (d)(iii-iv)). 

U.S. Environmental Protection Agency (EPA) released guidance on June 7, 2007 to use 

in setting reasonable progress goals. The goals must provide improvement in visibility for 

the most impaired days, and ensure no degradation in visibility for the least impaired 

days over the State Implementation Plan (SIP) period. The State must also provide an 

assessment of the number of years it would take to attain natural visibility condition if 

improvement continues at the rate represented by the reasonable progress goal. Figure 5

illustrates an example of how Uniform Rate of Progress is calculated. 

 

Figure 5. Example calculation of Uniform Rate of Progress

Modeled Visibility Projections for 2018

The CMAQ air quality model was used to simulate base period emissions and future 

emissions. The modeling results for the base year period (2002) and the year 

representing the end of the first planning period (2018) are used to develop relative 

response factors (RRF) for each component of particulate matter identified previously in 

this TSD. The relative response factors are multiplied by the measured species 

concentration data during the base period (for the measured 20% best and worst days). 

This results in daily future year species concentrations data. The projected concentrations 

are then used to derive daily visibility in deciviews and are averaged across all best and 

worst days to create the projected future visibility. The results of this procedure are 

plotted along with the uniform progress glide slope in Appendix M of the West Virginia

Haze SIP. 
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The modeling results presented in Appendix M of the West Virginia Haze SIP show all 

VISTAS sites are projected to meet or exceed the uniform rate of progress goals for 2018 

on the 20 percent worst days. In addition, no site anticipates increases in visibility

impairment relative to the baseline on the 20 percent best days. 

 

Summary of Photochemical Grid Modeling Results

In summary, the photochemical grid modeling, presented in the West Virginia Haze SIP, 

follow EPA’s modeling guidance and is acceptable to EPA. All VISTAS Class I sites are 

projected to meet or exceed the uniform rate of progress goal for 2018 on the 20 percent 

worst days. In addition, no site anticipates increases in visibility impairment relative to 

the baseline on the 20 percent best days. 

Contribution Assessment

The 1999 Regional Haze Rule requires States and Tribes to submit State Implementation 

Plans (SIPs) to the U.S. Environmental Protection Agency (USEPA) for approval by

January 2008 at the latest. The haze SIPs must include a “contribution assessment” to 

identify those states or regions that may be influencing specially protected federal lands 

known as Federal Class I areas. 4These states or regions would then be subject to the 

consultation provisions of the Haze Rule. The Haze Rule also requires a “pollution 

apportionment” analysis as part of the long-term emissions management strategy for each 

site.

As described in the Conceptual Description portion of this TSD, sulfate alone accounts 

for anywhere from one-half to two-thirds of total fine particle mass on the 20 percent 

haziest days at VISTAS Class I sites. As a result of the dominant role of sulfate in the 

formation of regional haze in the VISTAS area, VISTAS concluded that an effective 

emissions management approach would rely heavily on broad-based regional SO2 control 

efforts in the eastern United States.

Area of Influence for VISTAS Class I Areas 

There are 20 Class I areas located in the VISTAS area. The objective of the VISTAS 

Area of Influence analysis is to identify the geographic source regions that are 

contributing to visibility impairment at the Class I areas on the worst 20 percent visibility

days. This information is being used by the VISTAS states as part of the evaluation and 

demonstration of reasonable progress toward visibility improvement in Class I areas. In 

order to identify states whose emissions are most likely to influence visibility in VISTAS

Class I areas, VISTAS prepared a report entitled “VISTAS Area of Influence Analyses”

located in Appendix M of the West Virginia Haze SIP. 

Based on that work, VISTAS concluded that it was appropriate to define an “Area of 

Influence” (AOI) including all of the states participating in VISTAS plus other states 

outside VISTAS for which analyses indicated they contributed at least one percent (1%) 

of the sulfate ion in VISTAS Class I areas in 2002. 

Contribution Assessment Results

 

4 The Class I designation applies to national parks exceeding 6,000 acres, wilderness areas and national 

memorial parks exceeding 5,000 acres, and all international parks that were in existence prior to 1977.
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VISTAS States decided that any state or region that contributed at least 1 percent of total 

sulfate observed on 20 percent worst visibility days in 2002 is contributing significantly 

to the haze problem in that particular Class I area. 

With respect to sulfate, the Contribution Assessment estimated emissions from within 

VISTAS in 2002 contributed significantly to the total sulfate at Class I areas located 

within and nearby to the VISTAS region (see Appendix M of the West Virginia Haze 

SIP). The contribution of sulfate at these Class I areas from other regions outside the 

VISTAS were also significant. 

Studies showed that West Virginia “contributes” to the following Class I areas: Dolly

Sods Wilderness Area, Otter Creek Wilderness Area, James River Face Wilderness Area, 

Linville Gorge Wilderness Area, and Shenandoah National Park. Therefore, this SIP 

focuses on how West Virginia’s control measures will improve visibility in these areas. 

 

BART

On July 6, 2005 (70 FR 39104) EPA finalized 40 CFR 51 – Regional Haze Regulations 

and Guidelines for Best Available Retrofit Technology (BART) Determinations 

addressing the issues from the Circuit Court decisions. The BART requirements were 

most recently updated on October 5, 2006. BART is defined as an emission limitation 

based on the degree of reduction achievable through the application of the best system of 

continuous emission reduction for each pollutant, which is emitted by a BART-eligible 

source. The changes to the rule included how the States would identify the best system of 

continuous emission control technology and by which States can consider an individual 

facility’s contribution to regional haze when determining to require controls, and what 

the level of control should be met. The rule changes also clarified the requirements 

associated with demonstrating how emissions trading or alternative programs may be 

used as an alternative to applying Best Available Retrofit Technology (BART) 

Requirements. 

Congress defined sources potentially subject to BART - as major stationary sources, 

including reconstructed sources; from one of 26 identified source categories which 

included utility and industrial boilers, and large industrial plants such as pulp mills, 

refineries and smelters; which have the potential to emit 250 tons per year or more of any 

air pollutant, and which were placed in operation between August 1962 and August 1977. 

[CAA 169A (b)(2)(A) & (g)(7)].

Five Factor Analysis for Each BART Source 

States are required to determine BART for each BART-eligible source. According to 40 

CFR 51.308(e)(1)(ii)(A) the determination of BART must be based on an analysis of the 

best system of continuous emission control technology available and associated emission 

reductions achievable. 40 CFR 51.308(e)(1)(ii)(A) requires the analysis to take into 

consideration the following five factors for the technology available : 

1) The costs of compliance, 

2) The energy and non-air quality environmental impacts of compliance, any
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3) Pollution control equipment 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 use of the technology. 

Under the BART Guidelines, WVDAQ may consider exempting some sources from

BART if it is found that they do not cause or contribute to visibility impairment in a 

Class I area. In accordance with the BART guidelines, WVDAQ chose to perform 

source-specific analyses to determine which sources cause or contribute to visibility

impairment using the California Puff Model (CALPUFF). The CALPUFF modeling 

protocol used for determining which facilities are subject to BART is included in 

Appendix H of the WV Haze SIP. In accordance with the Guidelines, a contribution 

threshold of less than 0.5 deciviews was employed for determining which sources were 

exempt from BART.

CALPUFF is a multi-layer, multi-species, non-steady state puff dispersion model which 

can simulate the time and space varying meteorological conditions on pollutant transport, 

transformation and removal. CALPUFF uses three dimensional meteorological fields 

developed by the meteorological processing program CALMET. 

CALPUFF contain algorithms for near source effects such as building downwash, 

traditional plume rise, partial plume penetration, sub-grid scale terrain interactions, as 

well as long range effects such as pollutant removal (dry and wet deposition), chemical 

transformation, vertical wind shear, over-water transport, and coastal interaction effects.

The CALPUFF modeling performed for all of West Virginia’s BART sources conforms 

to EPA modeling guidance. A detailed description of the CALPUFF modeling can be 

found in Appendix H of the West Virginia Haze SIP.

West Virginia Sources Subject to BART

Twenty-one (21) of West Virginia’s twenty-two (22) BART-eligible sources submitted

exemption modeling demonstrations. Nineteen (19) of the twenty-one (21) sources were 

able to demonstrate exemption. Additional details are available in Appendix H. Capitol 

Cement (003-00006) was the only BART-eligible source which chose not to submit 

exemption modeling.

Although PPG Industries initially modeled a visibility impact greater than 0.5 deciviews 

on multiple Class I areas, PPG elected to accept a permit limit on its BART eligible unit 

which reduces its visibility impact to below the exemption threshold of 0.5 deciviews of 

impact at any Class I area. Permit, R14-027B, requires 4690.56 tpy of SO2 emission 

reductions from Boiler #5 by May 1, 2008. Therefore, PPG is considered BART exempt.

Only Dominion’s Mt. Storm Power Station in Mt. Storm was unable to demonstrate a

contribution of less than 0.5 deciview at all Class I area within 300 km from their BART 

eligible sources. Therefore, Mt. Storm was the only source considered to be “subject to 

BART” and required to submit a permit application, containing their evaluation of 

potential BART options and a proposed BART determination. Mt. Storm submitted a 
16

BART determination on November 3, 2006. A copy of the BART determination was sent 

to EPA and the Federal Land Managers for review on January 22, 2007. On September 

5, 2007 the company submitted a permit application to incorporate the results of the 

BART determination. The WVDAQ published a legal ad, which commenced the thirty

day public comment period, on September 18, 2007. A copy of the application and draft 

permit were sent to the Federal Land Managers for review, via email, on September 17, 

2007. Permit R13- 2735 was issued December 13, 2007. [See Appendix L for copies of 

application, draft permit and final permit.] The current PM controls at Mt. Storm were 

determined to satisfy BART, however, the allowable PM10 emission rate was lowered 

from 0.05 lb/mmBtu to 0.03 lb/mmBtu, resulting in a reduction of up to 508 tpy per unit, 

or a maximum reduction of 1524 tpy. 

Capitol Cement in Martinsburg chose not to submit exemption modeling, but simply to

acknowledge that Kiln 9 was BART-subject. Capitol Cement had previously applied for 

and been granted a PSD (Prevention of Significant Deterioration) permit (R14-026, 

issued June 2, 2005) for the replacement of two existing long wet process cement kilns 

and associated clinker coolers with a modern precalciner system and associated 

equipment. The only BART-eligible unit at the facility (Kiln 9) was one of the two kilns 

being replaced, and the permit included a requirement for the permanent shutdown of the 

existing kilns when full-production was achieved with the replacement kilns, or no later 

than 180 days after startup. Therefore, the company requested that the permit be modified 

to require the permanent shutdown of the Kiln 9 system by the BART compliance 

deadline or when full-production was achieved with the replacement kilns, or no later 

than 180 days after startup, whichever came first. The WVDAQ issued an Administrative 

Update to permit R14-026B on October 11, 2006, requiring that “Operation of the 

existing kiln 9 system shall permanently cease after the pre-heater-precalciner kiln 

system achieves full production or within 1280 days after the pre-heater-precalciner kiln 

system first becomes operational or before the BART compliance deadline 

(approximately 2013) whichever comes first”. [See Appendix L for copies of letter and 

permit.] The modifications at Capitol Cement are expected to result in 1,741.51 tpy of 

SO2 reductions, 1,374.81 tpy of NOx reductions, and 66.01 tpy of PM10 reductions. 

Summary of EPA’s Technical Findings

The technical analyses and modeling used to assess uniform rate of progress and to 

support the LTS were successfully developed consistent with EPA’s interim and final 

modeling guidance. All VISTAS sites and MANE-VU sites, significantly impacted by 

VISTAS sources, are projected to meet or exceed the uniform rate of progress goal for 

2018 on the 20 percent worst days. In addition, no site anticipates increases visibility

impairment relative to the baseline on the 20 percent best days. The technical analyses 

and modeling used in the West Virginia Haze SIP’s contribution assessment and 

prediction of visibility impacts from BART controls comply with EPA modeling 

guidance and recommendations. EPA finds the VISTAS technical modeling analyses 

presented in the West Virginia Haze SIP to be acceptable because the models that were 

used were applied according to EPA modeling guidance.