May 17 2006

Peter Courtney

Georgia Department of Natural Resources

Environmental Protection Division - Air Protection Branch

4244 International Parkway, Suite 120

Atlanta, Georgia 30354

Re: Protocol for Best Available Retrofit Technology Exemption Modeling: Cedar Springs Mill

Georgia-Pacific Corporation (GP) is pleased to submit this Protocol for Best Available Retrofit 

Technology (BART) Exemption air modeling for our pulp and paper facility in Cedar Springs,

Georgia. BART is required for any eligible source that ‘‘emits any air pollutant which may 

reasonably be anticipated to cause or contribute to any impairment of visibility” in any 

mandatory Class I federal area. 40 CFR Part 51 Appendix Y states, “You can use dispersion 

modeling to determine that an individual source cannot reasonably be anticipated to cause or 

contribute to visibility impairment in a Class I area and thus is not subject to BART.” The 

enclosed protocol describes our proposal for this dispersion modeling. While many of the 

components of a protocol for this analysis are thoroughly documented in the VISTAS common 

protocol, this document provides source-specific information. As we have discussed on the 

telephone, these analyses will apply the refined (i.e., 4 kilometer) meteorological datasets and 

iterate emission rate scenarios to correlate a level of impairment below a cause/contribute

threshold or otherwise qualify the facility as an exempted source.

We look forward to addressing any questions or concerns you have with this protocol. Please 

contact me at (404) 652-4293; FAX (404) 654-4706; mjaguila@gapac.com.

Sincerely,

Mark J. Aguilar P.E.

Senior Environmental Engineer

Georgia-Pacific Corporation

Cc: Cliff Chamblee, Cedar Springs Mill

 Scott Matchett, GP Atlanta
GP Cedar Springs Mill BART Exemption Modeling Protocol

May 17, 2006

P:\BART exemption Protocol CSO.doc i

1.0 INTRODUCTION............................................................................................................. 1

1.1. Overview of the Regional Haze BART Process............................................................... 1

1.2. Organization of the Protocol............................................................................................. 2

2.0 SITE DESCRIPTION....................................................................................................... 3

3.0 VISTAS CONTRIBUTION TO CALPUFF MODELING ........................................... 8

4.0 MODEL DISCUSSION.................................................................................................... 8

4.1 Exemption Procedures.................................................................................................. 8

4.2 CALPUFF Configuration............................................................................................. 9

5.0 RESULTS AND DETERMINATION OF IMPAIRMENT........................................ 10

5.1 Impact Threshold........................................................................................................ 10

5.2 Presentation of Modeling Results.............................................................................. 10

6.0 QUALITY ASSURANCE PLAN................................................................................... 13
GP Cedar Springs Mill BART Exemption Modeling Protocol

May 17, 2006

P:\BART exemption Protocol CSO.doc 1

1.0 INTRODUCTION

1.1. Overview of the Regional Haze BART Process

Under regional haze regulations, the Environmental Protection Agency (EPA) has issued final

guidelines dated July 6, 2005 for Best Available Retrofit Technology (BART) determinations

(70 FR 39104-39172). The regional haze rule includes a requirement for BART for certain large 

stationary sources, such as our pulp & paper facility in Cedar Springs, Georgia. Sources are

BART-eligible if they meet three criteria on potential emissions of visibility-impairing 

pollutants, the date when the source was put in place and fall within one of the source categories

listed in the guidance. The guidance requires a BART engineering evaluation using five

statutory factors for any BART-eligible source that can be reasonably expected to cause or

contribute to impairment of visibility in any Class I areas protected under the regional haze rule. 

(Note that, depending on the five factors, the evaluation may result in no control.) Air quality

modeling is an important tool available to the States to determine whether a source can be

reasonably expected to contribute to visibility impairment in a Class I area.

The process of establishing BART determination consists of four steps:

1) Identify whether a source is “BART-eligible” based on its source category, when it was 

put in service, and the magnitude of its emissions of one or more “visibility-impairing” air 

pollutants. The BART guidelines list 26 source categories of stationary sources that are

BART-eligible. Sources must have been put in service between August 7, 1962 and 

August 7, 1977 in order to be BART-eligible. Finally, a source is eligible for BART if

potential emissions of visibility-impairing air pollutants are greater than 250 tons per year. 

Qualifying pollutants include primary particulate matter (PM10) and gaseous precursors to

secondary fine particulate matter, such as SO2 and NOx. VISTAS has determined that

neither ammonia nor volatile organic compounds (VOCs) should be included as visibilityimpairing pollutants for BART eligibility.

2) Determine whether a BART-eligible source can be excluded from BART controls by

demonstrating that the source cannot be reasonably expected to cause or contribute to

visibility impairment in a Class I area. The preferred approach is an assessment with an air 

quality model such as CALPUFF or other appropriate model followed by comparison of

the estimated 24-hr visibility impacts against a threshold above estimated natural

conditions to be determined by the States.1 The threshold to determine whether a single

source “causes” visibility impairment is set at 1.0 deciview (dv) change from natural

conditions over a 24-hour averaging period in the final BART rule (70 FR 39118). The

guidance also states that the proposed threshold at which a source may “contribute” to

visibility impairment should not be higher than 0.5 dv although, depending on factors

affecting a specific Class I area, it may be set lower than 0.5 dv. The test against the

 

1 Guidance to determine the level of the natural conditions baseline for BART modeling purposes is still under 

development by VISTAS member states and EPA Region IV.
GP Cedar Springs Mill BART Exemption Modeling Protocol

May 17, 2006

P:\BART exemption Protocol CSO.doc 2

threshold is “driven” by the contribution level, since if a source “causes”, by definition it

“contributes”. 

3) Determine BART controls for the source by considering various control options and

selecting the “best” alternative, taking into consideration:

a) Any pollution control equipment in use at the source (which affects the 

availability of options and their impacts),

b) The costs of compliance with control options,

c) The remaining useful life of the facility, 

d) The energy and non air-quality environmental impacts of compliance, 

and

e) The degree of improvement in visibility that may reasonably be 

anticipated to result from the use of such technology.

Note that if a source agrees to apply the most stringent controls available to BART-eligible 

units, the BART analysis is essentially complete and no further analysis is necessary (70

FR 39165).

4) Incorporate the BART determination into the State Implementation Plan for Regional

Haze, which is due by December 2007.

Step 2 described above reflects 40 CFR Part 51 Appendix Y which states that, “You can use 

dispersion modeling to determine that an individual source cannot reasonably be anticipated to 

cause or contribute to visibility impairment in a Class I area and thus is not subject to BART.” 

(70 FR 39162) This “individual source attribution approach” determines if a BART-eligible 

source (i.e., collection of eligible emission units at a source) is predicted to cause or contribute to 

visibility impairment in a Class I area. As mentioned above, a predicted impact of 1.0 dv change

or more is considered to “cause” visibility impairment, and a predicted impact of 0.5 dv change 

or more is considered to “contribute”. Any source determined to cause or contribute to visibility 

impairment in any Class I area is subject to BART. 

1.2. Organization of the Protocol 

Section 2 presents facility-specific information. Section 3 presents the contribution by VISTAS for 

the BART exemption analyses. Section 4 summarizes the exemption process, modeling approach, 

and model configuration. Section 5 presents the criteria and processing of model results to 

demonstrate what impairment, if any, the facility is predicted to create in the Class I areas. Section 

6 presents the Quality Assurance Plan. 
GP Cedar Springs Mill BART Exemption Modeling Protocol

May 17, 2006

P:\BART exemption Protocol CSO.doc 3

2.0 SITE DESCRIPTION

GP operates the Cedar Springs Mill in Cedar Springs (Early County) approximately 30 

kilometers east-southeast of Dothan, Alabama along the state border. The facility manufactures 

corrugated containerboard. The facility is located in a rural area, and few residential areas are 

near the Mill. The Mill is located along the Chattahoochee River on State Route 273. The area 

surrounding the facility includes a river floodplain, and slight rises in terrain. Figure 1 depicts 

the location of the Mill and illustrates the adjacent terrain.

The list of potentially BART-eligible emission units are summarized in Table 1. 

Table 1. Model Parameters for Potentially BART-Eligible Sources at GP Cedar Springs

UTM NAD27 Z.16 (m)

Permit ID Source Description

Stack 

Ht 

(Ft) East North

Elevation 

(Ft)

Stack 

Diameter 

(Ft)

Exit 

Velocity 

(Ft/Sec)

Exit Temp 

(deg F)

R402(a) Recovery Boiler No. 3 246 681480 3449449 140 9 44.7 490

R402(a) Recovery Boiler No. 3 246 681480 3449445 140 9 44.7 490

R406 Smelt Tank No. 3 248 681485 3449404 140 6 23.1 155

CG Coal Handling (b) NA 681470 3449330 140 NA NA NA

U500 Power Boiler No. 1 350 681480 3449342 140 12 31.4 140

U501 Power Boiler No. 2 350 681487 3449340 140 12 31.4 140

L600 Lime Kiln No. 1 82 681605 3449658 140 6 31.7 170

L601 Lime Kiln No. 2 82 681591 3449668 140 6 31.7 170

L636/637 Lime Handling(LEG2) 47.8 681629 3449584 140 2 15 70

MOG1 Paper Machine Nos. 1 -3 (c) 100 681603 3449310 140 5.4 47 137

The following emission units only emit VOCs and are not included in the CALPUFF analysis

MEG1 Stock Chest Sources NA NA NA 140 NA NA NA

WWTS Wastewater Treatment NA NA NA 140 NA NA NA

POG1 Pulp Mill Sources NA NA NA 140 NA NA NA

SOG1 NSSC Process NA NA NA 140 2.5 31.1 109

LOG1 Recaust. Area NA NA NA 140 NA NA NA

Notes:

(a) Recovery Boiler No. 3 exhausts via two stacks

(b) Coal handing is a fugitive only source with the following parameters 7.6m release height, 1m initial 

horizontal and lateral dimension (i.e., sigma-y and sigma-z). GP determined these parameters by weighting 

the individual points by potential PM emission rate

(c) Paper Machines are vented through 36 similar stacks across a common roof. The table lists the center of 

the building and typical exhaust parameters for an individual point. 
GP Cedar Springs Mill BART Exemption Modeling Protocol

May 17, 2006

P:\BART exemption Protocol CSO.doc 4

Figure 1. Topographic Map of Cedar Springs Mill Vicinity

(Source: USGS)
GP Cedar Springs Mill BART Exemption Modeling Protocol

May 17, 2006

P:\BART exemption Protocol CSO.doc 5

The two Power Boilers are permitted to burn coal, bark/woodwaste, tire-derived fuel, No. 6 oil, 

peanut/pecan hulls, used lubrication oil, and natural gas. Because of the various fuel mixtures, 

the analysis may apply several speciation profiles, based on actual fuel mix practices during the 

2002 – 2004 baseline . Table 2 presents the available fuel-specific speciation profiles. The Mill 

and the Department will further discuss the possible fuel mix scenarios to apply in the model, as 

appropriate.

Table 2. Maximum 24-hour Average Emissions, Cedar Springs Mill Power Boilers Nos. 1 and 2

Parameter

All Fuels combined

Boiler 1 Boiler 2

SO2 Emissions(a) lb/hr 703 703

H2SO4 Emissions(a) lb/hr 2.9 2.9

NOx Emissions (a) lb/hr 400 400

PM10 Emissions(a) lb/hr 55 55

Emission Speciation For Individual Boilers by Fuel 

With Wet Scrubber

Coal Oil (b) Woodwaste Natural Gas

PM Speciated Emissions 

Filterable (lb/hr) -- 30.5 -- 25%

Condensable (lb/hr) -- 24.5 -- 75%

Fine Elemental Carbon (lb/hr) -- 2.2 -- --

Condensible IOR (lb/hr) -- 20.8 -- --

PM Fine (lb/hr) -- 29.3 -- --

Notes:

(a) Permit 2631-099-0001-V-01-8 issued in November 2005 reduced the potential maximum allowable 

emission rates below previous permit limits. Listed emissions in this table reflect the new limits. The 

permit also requires the installation of CEMs to demonstrate compliance. At the time of this protocol, the 

Mill has completed one CEM installation.

(b) Speciation computed using 55 lbs/hr and a maximum sulfur % in oil of 3%. GP computed the speciation 

using the spreadsheets (Residual Oil with Wet Scrubber) provided by VISTAS from the USFS.

Table 3 presents emission information for the additional potentially BART-eligible emission 

units.

Figure 2 presents a regional map showing the Cedar Springs Mill and PSD Class I Areas within 

300 km.
GP Cedar Springs Mill BART Exemption Modeling Protocol

May 17, 2006

P:\BART exemption Protocol CSO.doc 6

Table 3. Emission Rate Information for Additional Potentially BART-Eligible Emission Units at GP Cedar Springs

Maximum Actual 24-hr Emissions (lb/hr) PM Speciation

SO2 H2SO4 NOx PM10 PM2.5 Filterable Condensable EC

Organic 

Aerosols NOx SO4 PM Fine

R402 (a) 916.1 120.8 208.3 45.7 35.5 86% 14% 0.89% 8.83% 0.30% 9.86% 80.12%

CG (b) 0 0 0 0.181 0.027 100 0 -- -- -- -- --

L600 (c) <50 52.8 20.0 17.3 98% 2% -- -- -- -- --

L601 (c) <50 52.8 11.1 9.6 98% 2% -- -- -- -- --

L636/637 0 0 0 11.7 11.7 100 0 -- -- -- -- --

MOG1(d) 0 0 0 <20

R406 (e) 14.1 2.6 15.1 15.1 84% 16% -- -- -- 0.40% --

Notes:

(a ) PM10 and PM2.5 based on PMtotal emissions of 68.19 lb/hr and estimated fractions of 67% and 52% by NCASI, respectively

(b) PM2.5 fraction based on DRAFT AP-42 Section 13.2.4 (June 2006) SO2 and H2SO4 emissions reflect potential emission rates

(c) L600 and L601 PM10 emissions reflect the permit limit and the maximum stack test value during 2001-2005, respectively. SO2 emissions reflect historical testing

of less than 1⁄2 of the current permit limit of 113 lbs/hr for each kiln. Actual emissions have not been measured since before 2002.

(d) The paper machine emissions are fugitive in nature and have not been quantified. The work area exhausts via 30 roof-mounted fans. GP conservatively estimated 

the emissions as less than 20 lbs/hr

(e) PM10 emission rate of 15.1 lbs/hr reflects the maximum source test result during 2000-2006 and was measured as total PM (Method 5). PM2.5 conservatively 

assumed to be equal to PM10 and PM total.
GP Cedar Springs Mill BART Exemption Modeling Protocol

May 17, 2006

P:\BART exemption Protocol CSO.doc 7

700 750 800 850 900 950

UTM East (km)

Figure 2. Mandatory Class I Area Receptors within 300km of GP Cedar Springs

3350

3400

3450

U

T

M

N

o

rth (k

m)

St. Marks

Okefenokee

GP Cedar Springs
GP Cedar Springs Mill BART Exemption Modeling Protocol

May 17, 2006

P:\BART exemption Protocol CSO.doc 8

3.0 VISTAS CONTRIBUTION TO CALPUFF MODELING

For this application of BART Exemption Modeling, VISTAS/VDEQ has the following data 

bases developed by Earth Tech available:

• VISTAS version of the CALPUFF modeling system, maintained on the Earth Tech 

website. 

• 4-km CALMET output files for 2001, 2002, and 2003 produced as described in the 

VISTAS Common Protocol. 

• CALMET with a software modification to allow the meteorological data inputs into 

CALMET to be used to generate finer grid CALMET files without having to go back 

to the original MM5 output files

• File with CALPUFF model configuration and settings sufficient to replicate 

CALPUFF modeling done for VISTAS using 12 km CALMET, including

o Ozone data used to run CALPUFF

o Ammonia data used to run CALPUFF and to partition NO3 in POSTUTIL.

o Background concentrations files for use in POSTUTIL 

4.0 MODEL DISCUSSION

4.1 Exemption Procedures

For determining if this BART-eligible source is subject to a full BART engineering analysis, GP 

is beginning with the most refined dataset available from VISTAS. The fine grid analyses will

use the 98th percentile impact value for the 24-hr average at each Class I area. The analysis will

use either the 8th highest day in each year or the 22nd highest day in the 3-year period,

whichever is more conservative, for comparison to the exemption threshold.

The analysis uses the same model assumptions for pre-BART visibility impact and for BART

options modeling: establish baseline visibility from the pre-BART run; change one control at a

time; and evaluate the change in visibility impact, (i.e., the delta-deciview). Note that “no

control” may constitute BART.

The VISTAS Common Modeling Protocol consistently recommends conservative assumptions. 

Individual States ultimately have responsibility to determine which, if any, BART controls are

recommended in their State Implementation Plans (SIPs). The VISTAS protocol presents

additional detailed information on the meteorological fields, and specific settings for CALPUFF

and CALPOST (see section 4.33 of the VISTAS Common Modeling Protocol).
GP Cedar Springs Mill BART Exemption Modeling Protocol

May 17, 2006

P:\BART exemption Protocol CSO.doc 9

4.2 CALPUFF Configuration

Source emissions should be defined using the maximum 24-hour actual emission rate during

normal operation for the most recent 3 or 5 years. If maximum 24-hr actual emissions are not

available, continuous emissions data, permit allowable emissions, potential emissions, and

emissions factors from AP-42 source profiles may be used as available. Specific configuration

settings presented in the VISTAS Common Modeling Protocol are listed below:

• Use CMAQ modeling data from 2001-2003 to determine background concentrations of

SO4 and total NO3 (HNO3 + NO3). CMAQ data in CALPUFF-ready format will be

provided for each Class I area by VISTAS. After running CALPUFF for an individual

facility, repartition NO3 in POSTUTIL using the CMAQ background data, including that

for NH3. At the time of writing this protocol, hourly ammonia data is available for 2002. 

VISTAS has not yet made a final recommendation to States for 2001 and 2003. It is

possible that 2002 monthly values be applied for the same months for these two years.

• Use ozone data from non-urban monitors as the background ozone input. 

• Use the Pasquill-Gifford dispersion method.

• In CALPOST, use Method 6 with monthly average RH for calculating extinction, as

recommended by the EPA. 

• Use EPA default calculations of light extinction under current and natural background

conditions.

The major features and options of the meteorological and dispersion model are summarized and 

discussed in the VISTAS Common Modeling Protocol (revised through March 9, 2006).

As also discussed in the VISTAS Common Modeling Protocol, CALPUFF is currently not

recommended for addressing visibility impacts from VOC because its capability to simulate

secondary organic aerosol formation from VOC emissions is not adequately tested, especially for 

anthropogenic emissions. (Separately, condensable organic carbon can be calculated from

PM10.) 

EPA has given states the option to address ammonia (NH3) emissions from BART-eligible 

sources. VISTAS has also contracted with Georgia Tech to perform emissions sensitivities using 

CMAQ v 4.4 with a refined SOA module and the Jun-Jul and Nov-Dec periods in 2002. At the

time of this protocol, GDNR is not requesting the objective treatment of ammonia emissions

from the source.
GP Cedar Springs Mill BART Exemption Modeling Protocol

May 17, 2006

P:\BART exemption Protocol CSO.doc 10

GP intends to begin the analysis with the available 4-km meteorological datasets. Once initial

results are determined, we may need to address additional analysis options, including defining 

coastline information to refine the St. Marks NWA impact analyses.

5.0 RESULTS AND DETERMINATION OF IMPAIRMENT

5.1 Impact Threshold

The final BART guidance recommends that the threshold value to define whether a source

“contributes” to visibility impairment is 0.5 dv change from natural conditions (although states

may set a lower threshold). The 98th percentile (8th highest annual) 24-hr average predicted

impact at the Class I area, as calculated using CALPOST Method 6 (monthly average relative

humidity values), is to be compared to this contribution threshold value. For this comparison, the 

predicted impact at the Class I area on any day is taken to be the highest 24-hr average impact at 

any receptor in the Class I area on that day. (Note that the receptor where the highest impact

occurs can change from day to day.) According to clarification of the BART guidance received

from EPA, for a three-year simulation the modeling values to be compared with the threshold are 

the greatest of the three annual 8

th highest values or the 22nd highest value over all three years

combined, whichever is greater. 

5.2 Presentation of Modeling Results 

The CALPOST processing computes the daily maximum change in deciviews. A sample of the

summary table produced by CALPOST is shown in Table 3. For evaluating compliance with the 

VISTAS screening threshold, the highest change in extinction value, located at the bottom of the 

CALPOST list file is compared to the threshold value (e.g., 0.5 dv). For example, in the sample 

shown in Table 3, the summary at the bottom shows that the highest visibility impact is 1.219 dv, 

with 9 days over the year showing values greater than 0.5 dv. Therefore this source would not

pass the initial analysis, and finer grid modeling would be required.

In addition to the highest change in deciview value on each day over all the receptors in a

particular Class I area, the CALPOST summary table in Table 3 contains the coordinates of the

receptor, receptor type (D indicates discrete receptors), the total haze level (background + source, 

in dv), the background haze in deciviews, the change in haziness (delta dv), the humidity term

applied to hygroscopic aerosols (F(RH)), and the contribution of each species to light extinction

(in percent of the total source contribution) for SO4, NO3, organics, elemental carbon, coarse

and fine particulate matter.

If the maximum predicted impact is above 0.5 dv, then these results will also be presented:

• Number of receptors within a single Class I area with impact > 0.5 dv

• Number of days at all receptors in the Class I area with impact > 0.5 dv

• Number of Class I areas with impacts > 0.5 dv
GP Cedar Springs Mill BART Exemption Modeling Protocol

May 17, 2006

P:\BART exemption Protocol CSO.doc 11

Section 4 of the VISTAS Common Modeling Protocol presents sample tables for these results.
GP Cedar Springs Mill BART Exemption Modeling Protocol

May 17, 2006

P:\BART exemption Protocol CSO.doc 12

Table 4. Example of CALPOST Output, Showing Maximum Daily Impacts of Source and Locations of Those Impacts.

YEAR DAY HR RECEPTOR COORDINATES (km) TYPE DV(Total) DV(BKG) DELTA DV F(RH) %_SO4 %_NO3 %_OC %_EC %_PMC %_PMF 

2001 2 0 3 20.540 79.782 D 5.397 5.358 0.039 4.314 44.33 47.22 3.07 1.07 0.00 4.30 

2001 3 0 9 31.680 79.822 D 4.566 4.421 0.145 1.767 40.75 33.89 9.19 3.24 0.00 12.94 

2001 4 0 1 24.723 77.951 D 4.540 4.540 0.000 2.076 0.00 0.00 0.00 0.00 0.00 0.00 

2001 5 0 77 30.228 94.571 D 4.950 4.939 0.011 3.144 43.13 44.74 4.64 1.45 0.00 6.05 

2001 6 0 1 24.723 77.951 D 5.181 5.166 0.015 3.772 38.58 56.05 1.90 0.70 0.00 2.76 

2001 7 0 3 20.540 79.782 D 6.366 5.745 0.620 5.439 44.98 44.99 3.69 1.26 0.00 5.08 

 .

 .

 .

2001 363 0 113 27.414 103.782 D 5.725 5.652 0.073 5.164 53.49 35.51 4.03 1.39 0.00 5.58 

2001 364 0 113 27.414 103.782 D 6.554 6.521 0.033 7.826 48.12 47.09 1.67 0.64 0.00 2.48 

2001 365 0 1 24.723 77.951 D 6.499 6.499 0.000 7.757 0.00 0.00 0.00 0.00 0.00 0.00 

--- Number of days with Delta-Deciview => 0.50: 9

--- Number of days with Delta-Deciview => 1.00: 2

--- Largest Delta-Deciview = 1.219
GP Cedar Springs Mill BART Exemption Modeling Protocol

May 17, 2006

P:\BART exemption Protocol CSO.doc 13

6.0 QUALITY ASSURANCE PLAN 

Air quality modeling covered under this protocol is an important tool for use in

determining whether a BART-eligible source can be reasonable expected to cause or

contribute to visibility impairment in a Class I area, and therefore whether this source

should be subject to BART controls, and if so, to determine the relative benefits of

various BART controls. The purpose of the quality assurance (QA) program is to

establish procedures for ensuring that products produced by the application of the

modeling techniques for BART studies satisfy the regulatory objectives of the BART

program. Section 6 of the VISTAS Common Modeling Protocol presents additional

detailed information on the QA plan. For any proposed CALMET windfields, GP will

continue to work with VDEQ to determine appropriate QA metrics.