Tulsa Refinery 

( 

~ Sunoco, Inc.

PO Box 2039 

November Tulsa OK 74102-2039 28,2006 

Mr. Eddie Terrill 

Division Director, Air Quality Division 

Oklahoma Department of Environmental Quality 

707 North Robinson, P.O. Box 1677 

Oklahoma City, Oklahoma 73101-1677 

Subject: Application for a Best Available Retrofit Technology (BART) Waiver 


(OAC 252:100-8-73) for the Sunoco Tulsa, Oklahoma Refinery 


Dear Mr. Terrill: 

This is in response to your letter of March 22, 2006, dealing with Best Available 


Retrofit Technology (BART) Determinations, Waivers, and Exemptions. Sunoco has 


reviewed BART eligibility of each source at the Tulsa refinery, and has conducted air 


quality modeling of BART -eligible sources in accordance with the guidelines 


contained in the Central Regional Air Planning Association (CENRAP) Protocol, as 


directed in your letter. 


The modeling results show that predicted maximum impacts from BART -eligible 

sources at the Tulsa refinery are less than 0.5 deciviews at the closest Class I area. 

Accordingly, Sunoco requests a waiver under OAC 252:100-8-73, so that the Sunoco 

Tulsa refinery will not be subject to further BART analysis or requirements. 

Z::Z11~ RECEIVED 

Andrew Haar 

Environmental Manager I NOV ~! 2006 1 

enclosures: BART Exemption Modeling Report 

cd-ROM AIR QUALITY

cc: \Lee Warden QQ]jQ 

W:\ENVIRONMENTAL\AIR\BART\SUNTULSA_BART_WAIVER.DOC n 1706 
FINAL REPORT 


Sunoco, Inc. 


Visibility Modeling Analysis 


Sunoco Tulsa, OK Refinery 

BART Exemption Modeling 

13 November 2006 

0021048 

RECEIVED 

NOV 292006 


A'~ QUALXiV 


Environmental Resources Management 


350 Eagleview Boulevard 


Suite 200 


Exton, Pennsylvania 19341 


W:\ ENVIRON~IENTAL\t\lR\ BAKI\SU1\OC0_TULS,UlARTjINAL.DOC II 1706 

! 
TABLE OF CONTENTS 

EXECUTIVE SUMMARY 

1.0 BACKGROUND AND OVERVIEW 1 


1.1 Tlze Regional Haze Rule and BART 1 


1.2 The Sunoco Tulsa Refinenj and Applicability of BART 2 


1.3 Report Organization 3 


2.0 MODELING METHODOLOGY 4 


2.1 BART Eligible Sources and Emissions Modeled 4 


2.2 Modeling and Meteorological Domain 8 


2.4 CALPUFF Modeling Setup 10 


2.5 CALPOST Post Processing 11 


3.0 RESULTS AND DISCUSSION 13 


LIST OF TABLES 

Table 2-1 Summary of BART Sources Considered in CALPUFF Modeling 

Table 2-2 Summary of Sources Included in IIMiscellaneousll Source 

Table 2-3 Summary of Sources Not Included in BART Modeling Analysis 

Table 2-4 Relative Humidity Correction Factors 

Table 2-5 Natural Background Concentrations 

Table 2-6 Monthly Average Ozone and Ammonia Concentrations 

Table 3-1 Summary of Maximum Visibility Impacts (in Delta-Deciviews) 

LIST OF FIGURES 

Figure 2-1 Locations of Class I Areas Relative to the Sunoco Tulsa Refinery 

APPENDIX A CD-ROM With Modeling Files 

ERM SUNOCO TULSA/002JO~8-03 13 NOVHIBER 2006 
EXECUTIVE SUMMARY 


Regulations developed by the USEP A under the Clean Air Act, related to 

the protection of visibility in certain national parks and wilderness areas 

(referred to as Class I Areas), will require the installation of the Best 

A vailable Retrofit Technology (BART) for some categories of existing air 

emissions sources. The Sunoco Tulsa Refinery was notified by the 

Oklahoma Department of Environmental Quality (ODEQ) that some 

sources at the refinery may be subject to the BART rule, adopted in 

Oklahoma as a regulation under the Oklahoma Administrative Code 

(OAC), Subchapter 8, Part 11. BART requirements apply to sources that 

were installed and commenced operation between August 1962 and 

August 1977. Several sources at the Tulsa Refinery meet this definition, 

and are therefore considered "BART -eligible". 

The ODEQ notification stated that facilities with BART -eligible sources 

may request an exemption from the BART requirements. The exemption 

must be based on air quality modeling that demonstrates an insignificant 

impact on visibility in Class I areas. The exemption modeling is to be 

performed, using the CALPUFF model, in accordance with a strict 

protocol spelled out in guidance documents provided by the Central 

Regional Air Planning Association (CENRAP), of which Oklahoma is a 

member. 

Sunoco has conducted modeling, using the CALPUFF model in 

accordance with the CENRAP protocol, and has evaluated the impacts of 

BART -eligible sources at the Sunoco Tulsa Refinery on visibility in four 

Class I areas: the Wichita Wilderness in Oklahoma; the Caney Creek 

Wilderness and Upper Buffalo Wilderness Areas in Arkansas; and the 

Hercules Wilderness Area in Missouri. Meteorological data for three 

years (2001, 2002, and 2003), as provided by CENRAP, were used in the 

modeling. This report provides a description of the methodology and 

results of the BART exemption modeling. 

Model results for all four Class I areas, over all three years modeled, show 

that the maximum visibility impacts are less than 67% of the BART 

exemption threshold. Based on these results, upon submittal and 

acceptance of the modeling report by ODEQ, the Sunoco Tulsa Refinery, 

will be exempt from further BART requirements. 

ERM SUNOCO TULSf\f0021O~8-03 13 NOVHIBER 2006
1.0 BACKGROUND AND OVERVIEW 

This report describes the methodology and results of a modeling analysis, 

using the CALPUFF screening approach as outlined in the CENRAP 

BART modeling guidelines. The analysis was conducted to determine if 

the Sunoco Refinery located in Tulsa, OK, owned and operated by Sunoco, 

Inc. (Sunoco) is subject to the BART rule. The results of the analysis, 

discussed further in this report, demonstrate that maximum facility 

impacts, using conservative approaches in the modeling and in specifying 

facility emissions, are substantially less than the visibility exemption 

threshold of 0.5 deciviews, in all Class I areas modeled. The Sunoco 

Refinery should therefore be exempt from further BART review. 

1.1 The Regional Haze Rule and BART 

On 6 July 2005 a final rule regarding Regional Haze Regulations and 

Guidelines for Best Available Retrofit Technology (BART) Determinations 

was published in the federal register. The final rule requires certain 

sources affected by the rule to install and operate BART controls. The 

BART provision of the rule affects facilities belonging to one of 28 source 

categories defined in the Clean Air Act (CAA) and emitting greater than 

250 tons per year of visibility impairing pollutants which include nitrogen 

dioxide (NOx), sulfur dioxide (502), and particulate matter (PMI0). 

Individual sources within these facilities, which were installed and 

commenced operation between 1962 and 1977, are subject to the BART 

process. The BART guidelines specify a step-wise approach for the states 

and other regulatory agencies to determine and establish emission limits 

for affected sources. For sources located in the Central United States, the . 	 . 

Central Region Air Planning Association (CENRAP) provides guidelines 

for BART affected sources. The individual states, however, are 

responsible for regulating the BART-subject sources and establishing 

source-specific emission limits. 

The Oklahoma Department of Environmental Quality (ODEQ) has 

developed a regulation, Oklahoma Administrative Code (OAC), 

Subchapter 8, Part II, to address the requirements of the BART rule. 

Under the regulation, a facility can request exemption from the BART rule 

as per OAC 252: 100-8-73, based on the following conditions: 

1. 	 If the SOx and NOx emissions from the facility are less than 40 tpy and 

the PMI0 emissions are less than 15 tpy; or 

ERM 	 1 SUNOCO TULSA/0021Q·18·03 13 NOVEMBER 2006 
1.2 

2. 	 If the facility demonstrates by modeling that the BART-eligible sources 

at the facility do not contribute to visibility impairment in any 

mandatory Class I federal areas. 

The ODEQ requires sources who intend to conduct dispersion modeling 

for the exemption from BART requirements to submit the modeling 

analysis by 1 December 2006. The exemption will be granted by EPA 

upon written concurrence from the AQD director. If the facility does not 

qualify for the exemption based on modeling, a BART determination is 

required to be submitted to the Department by 30 March 2007. ODEQ 

notified Sunoco about the applicability of BART for sources at the Tulsa 

Refinery by a letter dated 22 March 2006. 

The first step in the BART process is identifying sources which are subject 

to the BART process. BART-eligible sources at the Tulsa Refinery were 

identified based on a review of the Title V permit. . These "BART -eligible" 

sources are responsible for demonstrating if they qualify for an exemption 

from the rule based on estimates of visibility impacts in Class I areas. 

CENRAP has provided BART modeling guidelines which specify the 

requirements for individual sources to qualify for an exemption by 

conducting a visibility modeling analysis. The sources can conduct the 

analysis using the regulatory model, CALPUFF, to show that the impacts 

on visibility at Class I areas potentially affected by the source are less than 

the significance level established in the guidelines and adopted by the 

State. 

The Sunoco Tulsa Refinery and Applicability ofBART 

The Sunoco refinery in Tulsa, OK, is owned and operated by Sunoco, Inc. 

The Tulsa refinery is operated primarily to produce high quality 

lubricating oils by blending a mixture of crude oils from different sources. 

Refinery fuel gases, propane, butane, isobutane, normal butane, gasolines, 

kerosene, No.2 fuel oil, paraffin wax, petroleum coke, and Lube Extracted 

Feedstock (LEF) are some of the current by-products from making the 

lube oils. LEF is a mixture of unfinished streams that may also be 

transferred to third party purchasers. The operations at the Facility fit the 

description of the Petroleum Refineries category - one of the 28 sources 

categories listed in the BART rule. The potential emissions of NOx, SOx, 

and PM from all BART-eligible sources at the Facility are equal to 845 tpy, 

1,210 tpy, and 38 tpy, respectively. More than half of the units at the 

facility were built either before 1962 or after 1977. Only those units which 

were constructed and began operation within this time period are subject 

to the BART process. However, ODEQ has provided the opportunity to 

all BART-eligible sources through the regulation under Subchapter 8, Part 

11, to evaluate the visibility impacts resulting from the emissions from the 

ERM 	 2 SUNOCO TU1~SA/0021Q48·()3 B NOVHIBEH 2U06 
1.3 

BART -eligible sources on Class I areas to determine whether the facility is 

subject to the BART rule. 

, This report discusses the methodology adopted by Sunoco to ~etermine 

impacts on Class I areas, and summarizes the results of the air dispersion 

modeling. The Oklahoma regulations referred to the CENRAP modeling 

protocol to conduct the dispersion modeling analysis. Since Sunoco has 

followed the CENRAP modeling guidelines, no additional modeling 

protocol is required, according to ODEQ. 

Report Organization 

Section 2 of the report discusses the methodology adopted by Sunoco to 

conduct the dispersion modeling analysis. The BART eligible sources are 

identified and a summary of emissions and stack information is presented 

in this section. This section describes the modeling domain and the 

meteorological data used in the analysis. A discussion of the background 

visibility conditions at the Class I areas of concern is presented. Section 3 

presents the results and the conclusions which can be drawn from the 

analysis. 

ERM 3 5Ul\OCO TULSt\/oa21O~8.{j3 13 NOVEMBER 2006
2.0 MODELING METHODOLOGY 

The CENRAP modeling guidelines describe three categories of dispersion 

modeling: screening modeling, source-specific refined modeling, and 

alternative modeling analysis. This report presents the results of a 

screening modeling analysis for the Facility. The CALPUFF dispersion 

model and CALPOST post-processor, as recommended in the CENRAP 

BART guidelines, and the meteorological data developed and made 

available by CENRAP, were used in this analysis. The model impacts are 

to be compared with the visibility threshold of a 0.5 deciview change 

established by ODEQ for qualifying for an exemption from further BART 

evaluation. The model versions used in this analysis were those 

recommended by CENRAP: CALPUFF version 5.711a and CALPOST 

version 5.51. 

2.1 BART Eligible Sources and Emissions Modeled 

Sunoco has a total of 16 emissions units at the facility which are BARTeligible. These emissions units are BART-eligible because they were built 

and began operations between 1962-1977. Emissions units, the potential 

to emit (PTE), and the stack parameters associated with the emission units 

are summarized'in Table 2-1. The PTE values presented in the table were 

obtained from the existing Title V permit for the Tulsa Refinery; actual 

emissions for these sources have historically been considerably lower than 

the PTE. Stack parameters for some sources were not readily available; 

therefore emissions from these sources were combined into a single 

representative stack (noted as the "miscellaneous" stack in Table 2-1). 

Table 2-2 provides information on the emission units modeled with the 

representative stack. It should be noted that treating these sources by 

modeling a single stack will have an insignificant effect on the model 

predictions, because the closest Class I area to the facility is at a distance of 

greater than 230 kilometers from the facility. Table 2-3 prOVides 

information on the emission units which are not BART-eligible as they fall 

outside of the time period between 1962 and 1977. 

The CENRAP BART modeling guidelines specify that the 1/ ..24-hour 

average actual emission rate with normal operations from the highest 

emitting day of the year should be modeled" (Section 6.4.4). For Sunoco, 

this rate is likely to be lower than the rate represented by the PTE. 

Nonetheless, for the sake of simplicity, emission rates corresponding to 

the PTE for each source were modeled. 

ERM 4 Sl,;NQCO TULSA/00210~8·03 13 NOVEMBER 2,106 
Table 2-1 Summary of BART Sources CO/lsidered ill CALPUFF Modelillg 

Base Exit Stack 

Elevation Stack Temperature Velocity Diameter Installation 

Source ID Source Description (m) UTME UTMN Height (m) (K) (m,ls) (m) Date Potential Emissions (tpy) 

NOx PM S02 

---­

-U28··~ t-­ 214 #2 Plat PH-7 636.2 768136 4003693 30.78 1039.26 11.403 1971 11.4 0.85 89.7 

240 PDA B-40 640.1 768699 4003511 1262 587.04 9.955 0.914 1%2 11.4 0.85 90.1 

242 ILEUHI01 640.1 769101 4003453 27.43 543.15 6.527 0.914 1963 9.6 0.75 78.5 

244 LEU H-201 640.1 769101 4003445 3Q.48 . 619.26 2402 1.615 1%3 9~· 0.75 78.5 

109 #7 boiler 640.1 768565 4003597 18.29 429.82 29.362 1.524 1975 131.4 4.9 0.44 

110 #8 Boiler 640.1 768565 4003605 18.29 480.37 32.814 1.524 1976 131.4 4.9 0.44 

111 #9 Boiler 640.1 768571 4003560 24.38 403.15 27.541 1.524 1976 131.4 4.9 0.44 

245 MEKH-I01 640.4 769125 4003459 34.14 478.15 12.096 1.829 1977 35.5 2.7 1.45 

269 LEU Flare 638.1 769031 4OO3461L, ,.-35:Q~ 92204 0.001 0.3~~ 1976 0.19 - 0.51 _. 

266 WPUFlare 638.5 768850 4003750 4237 92204 0.001 0.381 - 0.12 - 0.1 

268 Coker Rare 633.9 768268 4003881 44.5 922.04 0.001 0.381 - 0.18 - 0.1 

267 #2 Alkyl Flare (plat) 632.5 768008 4003799 43.89 1273 20 1 - 2.2 - 13 

241 PDA Propane Comp Eng 640.1 768666 4003507 6.71 588.71 2064 0.152 - 56.04 0.14 0.01 

243N LEU H-I02 N 640.1 769109 4003460 38.1 558.15 8.013 1.615 1963 65.7 5.87 854 

257 #6 CT Circulation Pump 640.1 768515 4003593 5.49 616.48 15.396 0.305 - 19.5 0.49 om - Miscellaneous 640.1 768600 4003598 30.48 405.65 5:2~ 3.2 - 229.36 11.03 i-­ 3.09 

TOTAL 845 38 1,210 

---­ ._­

ER~l 5 SUNOCO TULSA/002104&-ll3 13 NOVEMlJER 2006 

Table 2-2 Summary or Sources Included in "Miscellaneous" Source 

Base Exit 

Elevation Stack VellKity Stack 

Source lD Source Description (m) UTME UTMN Height(m) Temperature (K) (mls) Diameter (m) Installation Date Potential Emissions (tpv) 

NOx PM S02 

208 UnifinerH2 CompEng - - - - - - - - 47.18 0.12 0.01

254 #2Q?prav Pump Eng - - - - - - - - 42.17 0.10 0.01 

255 #2 cr Circ Pump Eng - - - - - - - - 66.48 0.16 0.01 

258 #6 crSpray Pump Engine - - - - - - - - 35.03 0.09 om ..... EG6217 -------­

Emergency - - - - - - - - 3.62 0.11 0.61 

EG6218 Emergency - - - - - - - - 3.62 0.11 0.61 

EG6312 Emergency - - - - - - - - 3.62 0.11 0.61 

EG6289 Emergency - - - - - . - - 3.62 0.11 0.61 

EG6290 Emergency - - - - - - - - 3.62 0.11 0.61 

256 #3 cr Circulation Pump - - - - - - - - 20.40 0.51 om 

Cooling Towers - - - - - - - - - 9.50 -

TOTAL 229 11 3 

::> 

.~ 

.ER~I 6 SUNOCOTULSAjOO2I().18"()313 NOVEMBER 2006 
Table 2-3 Summary of Sources not considered ill CALPUFF Modeling (Installation Date Outside of the BART timeframe ofAug 1962 to Aug. 1977) 

Base Exit Slack 

Elevation Stack Temperature Velocity Diameter Installation 

Source ID Source Description (m) UTME UTMN Height(m) (K) (m/s) (m) Date Potential Emissions (tpy) 

NOx PM S02 

105A #1 Boiler 640.1 768600 4003598 30.48 405.65 5.925 3.2 1948 184 4.99 526 

1058 #2 Boiler 640.1 ·768600 4003598 30.48 405.65 5.925 3.2 1948 184 4.99 526 

106A #3 Boiler 640.1 768582 4003598 33.53 404.15 5.967 .3.2 . 1954 184 4.99 526 

238 PDA 8-30 640.1 768700 4003500 16.46 547.04 2558 0.914 1956 4.8 0.37 38.5 

1068 #4 Boiler 640.1 768582 4003598 33.53 404.15 5.967 3.2 1957 184 4.99 526 

206 Unifiner H-2 638.5 768139 4003649 20.12 573.71 6.362 1.372 1957 16.2 1.22 129 

207 Unifiner H-3 637.5 768137 4003661 23.47 522.04 50.604 0.61 1957 26.3 1.98 208 ------­ 1--­ 38 -­ 209 #2 Plat PH~1/2 636.2 768134 4003700 27.74 884.26 10.341 2134 1957 ~2.89 304 

210 #2PlatPH-3 637.1 768137 4003668 15.24 672.59 7.202 1.372 1957 15.8 1.22 U7 

211 #2 Plat PH-4 637.1 768136 4003675 15.24 454.82 4.928 1.524 1957 19.7 1.49 157 

213 #2 Plat PH-6 636.2 768141 I-------=-c _-------­ 1--------­ ---------­4003709 25.91 768.71 1.64 1.524 1957 (1) (1) (1) 

246 IMEKH-2 640.4 769130 400345~ ------­

18.95 483.15 12.957 Ul67 1960 21.5 1.63 172

201N CDUH-1,N#7 63--ZS­ 768162 4003517 41.15 521.48 7.279 2256 1961 171 4.66 491 

2015 CDU H-1,5#8 637.5 768163 4003502 41.15 518.15 7.232 2256 1961 171 4.66 491 

202 CDUH-2 638.1 768182 4003504 38.1 713.36 12.932 2134 1961 29.4 2.63 745 

203 CDUH-3 638.1 768182 4003504 38.1 713.36 12932 2134 1961 18.9 1.71 479 

212 #2 Plat PH-5 636.2 768148 4003711 27.43 731.48 2147 2134 1990 56.5 2 0.5 

225 

224 CokerH-3 

Coker 8-1 640.1 768395 4003829 34.14 620.37 11.914 1.676 1992 26.28 2 ~ 

640.1 768393 4003820 27.74 550.93 11.261 1.219 1995 9.17 2.12 8.76 

TOTAL 1,361 51 5,456 

(1) Emissions included with #2 Plat PH-5 


ERM 7 SUNOCO TUlSAI 0021 048..(13 13 NOVEMBER 2006 
2.2 Modeling and Meteorological Domain 

The Sunoco Refinery in Tulsa, OK is located in north-east Oklahoma, just 

west of Interstate 75 (1-75). The CENRAP modeling guidelines define 

three separate slightly overlapping modeling domains - north, central, and 

south - each of which have a grid resolution of 6 km. The extent of the 

central domain and the facility location is shown in Figure 2-1. Class 1 

areas within or close to CENRAP are also shown in this figure. The Tulsa 

Refinery is located at the center of the CENRAP central domain. 

The closest Class 1 area is approximately 230 kilometers from Tulsa. The 

CENRAP modeling guidelines state that Class 1 areas within 300 

kilometers of a facility should be modeled (Section 6.4.3). At distances 

greater than 300 kilometers, the capability of CALPUFF to accurately 

simulate individual source impacts is diminished. Options within 

CALPUFF, including the capability to split puffs at large distances, are 

available to address transport distances greater than 300 kilometers, 

however, the CENRAP guidelines recommend against using these 

options. 

Four Class I areas were selected for modeling, all of which are between 

200 and 300 kilometers of Sunoco. These Class 1 areas include Caney 

Creek Wilderness and Upper Buffalo Wilderness in Arkansas; Hercules 

Wilderness in Missouri; and Wichita Wilderness in Oklahoma. For each 

Class I area, receptor locations and elevations were developed based on 

the National Park Service receptor files. A total of 291 receptors were 

included in the modeling analysis. Figure 2-1 shows the location of Gass 1 

areas modeled to evaluate the impact of emissions from the Sunoco 

facility. 

ERM 8 SUNOCOTULSA/0021048.U3 BNOVEMllER2006 . 
°1 Figu,.. 2-1 Map Showing th~L""'fion ofCia" , M ... 

-100 

·200 

·300 

·400 

-500 

l11ill~Wild 

~--.-~--t-~---f-----_____-~---i 

Sunoco 

Tulsa 

* 

·600 

·700 

-800 

200 km 

. Map coordinates are in 

R.ia'" .• to the Sun",o Tu'.., 0 K R.nn. 

·300 -200 ·100 o· 100 200 300 400 500 600 

The background visibility conditions to be used in screening analyses are 

defined in the CENRAP modeling guidelines (Table 6-3 in the guidelines). 

These conditions are specified for the eastern and western U.S., where the 

dividing line between east and west is defined in the guidelines to be in 

the middle of the CENRAP region, e.g. Oklahoma is in the west and 

Arkansas is in the east. The Class I area in Oklahoma (the Wichita 

Wilderness) is in the west based on this definition, while the other Class I 

areas modeled are in the east. The monthly relative humidity adjustment 

factors, used in calculating visibility impairment for hygroscopic species, 

were obtained from EPA's 2003 document "Guidance for Estimating 

Natural Visibility Conditions under the Regional Haze Rule", as directed 

in CENRAP's guidance document. The relative humidity correction 

factors, and the natural background concentration values, are summarized 

in Tables 2-4 and 2-5, respectively, for each Class I area. 

ERM 9 SUNOCO TUISA/01l2104S·03 B NOVE~IBER 2006 
Table 2-4 Relative Humidity Correction Factors 

Class I Area 

Jan Feb Mar Apr 

Relative Humidity Factor (fRH) 

May Jun Jul Aug Sep Oct Nov Dec 

Caney Creek Wilderness 3.3 3.0 2.7 2.8 3.2 3.2 3.0 3.0 3.2 3.2 3.1 3.3 

Hercules Glades Wilderness 3.2 2.9 2.6 2.6 3.0 3.0 3.0 3.0 3.2 2.9 3.0 3.2 

Upper Buffalo Wilderness 3.2 2.9 2.6 2.7 3.1 3.1 3.0 3.0 3.2 3.0 3.0 3.2 

Wichita Mountains Wilderness 2.8 2.4 2.4 2.7 2.5 2.2 2.4 2.7 2.5 2.6 2.8 

Table 2-5 Natural Backgrolllld Concentratiolls 

Class I Area Average Natural Background Concenh'ations (ug/m3) 

West or Ammonium Ammonium Organic Elemental 

East Sulfate Nitrate carbon mass carbon Soil Coarse Mass 

Caney Creek Wilderness E 0.23 0.10 1.40 0.02 0.50 3.00 

Hercules Glades Wilderness E 0.23 0.10 1.40 0.02 = 0.50 3.00 

Upper Buffalo Wilderness E 0.23 0.10 1.40 0.02 0.50 3.00 

Wichita Mountains Wilderness W 0.12 0.10 0.47 0.02 0.50 3.00 

2.4 


CENRAP has developed the meteorological data for conducting sourcespecific BART analysis for eligible sources within the CENRAP region. 

The data covers the three-year time period from 2001 through 2003, and 

covers different extents for the three modeling domains described above. 

The grid spacing for each of the meteorological domains is 6 kilometers. 

The CALMET meteorological pre-processor was used by CENRAP to 

generate these data sets, and - consistent with the screening approach­

. CALMET was not used to re-create meteorological data sets in the present 

analysis. 5unoco obtained the central domain meteorological data sets for 

use in this BART exemption modeling. 

The CALMET meteorological data sets were evaluated by creating 

summaries of domain-wide meteorological parameters for each year. A 

review of this summary indicates thatranges and averages of all 

parameters appear to be reasonable. The diurnal pattern of the stability 

category and temperature values, however, indicates that the CALMET 

runs were conducted with the base time zone set to 0 instead of a value 

that reflects the location of the CENRAP states. This setting is not 

expected to affect the results of the modeling. 

CALPUFF Modeling Setup 

This section describes the input parameters and the setup used for 

conducting the CALPUFF modeling analysis. Emissions of NOx, 502, 

and PM10 from sources at the 5unoco facility emission sources were 

modeled at the PTE rates shown in Table 2-1. Downwash due to on-site 

structures was not modeled, since downwash impacts are important 

primarily in the immediate vicinity of the source and not at distances of 

several hundred kilometers. The parameter settings shown in the 

ERM 10 SUNOCO TULSA! 0021 048·03 13 NOVEMBER 2006
CENRAP modeling guidelines Appendix Bf i.e. the recommended settings 

for CALPUFF screening modeling, were used in this analysis with only a 

few changes. Some changes were necessary to ensure that the central 

domain settings were used. Other changes were as follows: 

XBTZ: the base time zone was set to 0 instead of 6, to allow use of 

the CALMET files developed by CENRAP; 

NSPEC: the number of species modeled was set to 6 instead of the 

recommended 10 to reflect the Sunoco facility emissions; 

NSE: the number of species emitted was set to 3 instead of the 

recommended 6 to reflect the Sunoco facility emissions; 

IVIS: visibility option was set to 0 (do not generate a relative 

humidity file) since post-processing for CALPUFF screening 

applications does not use this file; 

ICPRT: the print option was set to 0 (do not print to list file) to 

conserve output disk space. 

Ozone and ammonia concentrations are required in order for CALPUFF to 

simulate the S02 and NOx transformation chemistry that forms sulfates 

and nitrates, and subsequently the formation of particulate nitrate that is 

used to estimate visibility impacts. The domain-wide, monthly average 

ammonia concentrations provided by CENRAP were used in CALPUFF. 

Ozone concentrations were specified in two different ways, and 

CALPUFF was run with each option. The first used hourly ozone 

concentrations across the domain, based on CAMx model runs, as 

provided on the CENRAP ftp site. The hourly ozone file was provided for 

calendar year 2002, and this file was used to create hourly files for 2001 

and 2003 by simply changing the date. The second option utilized 

domain-wide monthly averages that were created from the hourly ozone 

file, where only daytime values (hours 6 am to:6 pm)were used to create 

the p.verages. Table 2-5 displays the monthly average ozone and ammonia 

concentrations used in CALPUFF. 

Table 2-6 Monthly Average Ozone and Ammonia Concentrations 

Concentrations (ppb) 

~ ~ ~ A~/~ ~ M ~ ~ ~ ~ ~ 

-,::O-zo-n-e--------+-2::-;;4~.1-,......-; 13:-;:0-7.1-T"""":;1:fsTT::::': 44.6 I 46.1 I 52.5 I 52.6 I 50.3 I 45.3 I 35.3 I 27.5 I 24.0

Ammonia 0.90 I 0.93 I i:18l 1.37 J 0.99 1 1.24 1 1.08 1 1.06 1 1.35 1 1.29 I 1.58 I 1.16 

CALPOST Post Processing 

The EPA and CENRAP BART guidance recommends that visibility 

impacts be evaluated against natural background conditions. Visibility 

impairment can be expressed in a number of different ways; the most 

ERM 11 SUNOCO TULSA/0021048-03 n NOVEMBER 2006 

2.5 
common and relevant to BART determinations include light extinction, 

deciviews, and visual range. 

Light extinction (Bext) is a measure of light scattered from the line of sight; 

this is related to visual range by: 

VR (km) = 3912/Bext (mm-1) 

e.g. Bext of20 (good visibilihj) corresponds to a visual range ofabout 200 

km; Bext of200 (poor visibilihj), about 20 km 

Deciviews provide a scale where equal changes in the numerical value 

represent equal changes in perception; deciviews are related to light 

extinction as follows: . 

dv=10*ln(Bext/10) 

e.g. Bext of20 (good visibilihj) corresponds to a dv of6.9; Bext of200 

(poor visibility), about 29.2 

Light extinction can be calculated from predicted or measured 

concentrations of visibility impairing pollutants.. The calculation is carried 

out as follows: 

Bext = [chi] x [fRH) x [EE] . 

where 

Bext: is the light extinction; 


chi: is the 24-hr average compound concentration; 


fRH: is the growth factor for hygroscopic compounds (e.g. sulfates 


and nitrates); 


EE: is the extinction efficiency of the compound. 


Compounds relevant to the 5unoco's evaluation are nitrates (formed from 

emissions of NOx), sulfates (formed from emissions of 502), and PM10 

(emitted directly). 

Total extinction due to source emissions are calculated from the 

concentrations predicted by CALPUFF, and total extinction due to natural 

background is calculated from the concentrations identified in Table 2-4 

(with a value of 10.0 added to account for clear air scattering). The total 

deciview value corresponding to source plus background is compared to 

background alone, and the difference is reported as the source impact. If 

the source impact is less than 0.5 deciviews for all Class I areas over all 

ERM 12 SUNOCO TUL5A/00210~8-0313 NOVEMBER 2006 
3.0 

years modeled, then the source qualifies for an exemption from BART 

requirements. The CALPOST processor was used to calculate light 

extinction due to source emissions and due to background, and the 

resultant change in deciviews. Parameters recomni.ended in the CENRAP 

modeling guidelines, Appendix D, were used in this analysis with 

appropriate adjustments made to the domain settings and to the species 

modeled. 

RESULTS AND DISCUSSION 

The CALPUFF model was run to evaluate the impacts of emissions from 

BART-eligible sources at the Sunoco Tulsa Refinery on visibility in four 

Class I areas. The model was run for three full years (2001-2003) of central 

domain meteorology. Two different approaches to the specification of 

ozone concentrations were used, with the full set of meteorology and 


Class I areas for each approach. CALPOST was used to calculate the 


. maximum change in visibility due to emissions from Sunoco sources, 


expressed as a change in deciviews. A summary of the CALPUFF 

visibility modeling results is presented in Table 3·1. The results reported 

in Table 3-1 represent the maximum predicted impact over each year at all 

receptors. The maximum change in visibility values resulting from the 

emissions of BART eligible sources from the Sunoco facility is 0.335 

deciviews for the year2001 at Caney Creek Wilderness. Therefore, the 

viSibility impacts were less than the threshold of 0.5 deciview at all Class I 

areas within 300 Kilometers from the facility. 

It should be noted that EPA guidance allows for using the 98th percentile 

prediction (i.e., the 8th high value out of a full year) to evaluate visibility 

impacts. The CENRAP CALPUFF screening procedure, however, calls for 

comparison of the maximum impact to the 0.5 deciview threshold. The 

98th percentile impacts from Sunoco would be substantially lower than 

shown in Table 3-1. 

ODEQ notified Sunoco Tulsa Refinery that some of the sources at the 

facility might be eligible for BART based on the source category to which 

the refinery belongs, potential emissions of NOx, SOx, and PM from the 

refinery, and the dates on which the sources started operating. Based on 

the dispersion modeling analysis using CALPUFF, the impacts from the 

BART eligible sources are less than the guideline thresholds - therefore the 

Sunoco Tulsa Refinery is exempt from further BART evaluation. 

13 5UNOCO TUL5A/002104S-03 13 NOVEMBER 2006 
Table 3-1 Summary of Visibility Impacts from Sunoco Tulsa Refinery BART Eligible Sources 

Class I Area 2001 2002 2003 

Cane~ Creek Wilderness 

Hercules-Glades Wilderness 

0.335 

0.128 

0.273 

0.075 

0.139 

0.122 

UI!l!er Buffalo Wilderness 

Wichita Mountains Wilderness 

0.107 

0.139 

0.155 

0.203 

0.210 

0.197 

Model results are expressed in terms of the visibility change from 

natural background conditions in deciviews. 

No predicted values exceed the BART threshold of 0.5 deciview change 

ERM 14 SUNOCO TUl_~t\/0021048-0313 NOVEMBER 2006