773 San Marin Drive, Suite 2115, Novato, CA 94998 P: 415 - 899 -0700 F: 415 - 899 -070 7 www.environcorp.com

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### 21 February 2013 

# MEMORANDUM To: Ellen Belk, EPA Region 6 Cc : Susan Wolf, RTI International From: Uarporn Nopmongcol, Greg Yarwood Subject: 2002 Baseline CAMx Simulation, Texas Regional Haze Evaluation [ Contract EP -W-011 - 029 ] ENVIRON is assisting EPA by performing modeling of regional haze impacts of selected sources in Texas The analysis buil ds upon modeling of 2002 conducted previously for CENRAP by ENVIRON . The CENRAP database was enhanced to include a 12 km grid over Texas and nearby Class I areas, and updated to use with the latest version of the Comprehensive Air Quality Model with extensions (CAMx; ENVIRON, 2012 ) . This memorandum documents the new 2002 baseline modeling setup and results. 

## INTRODUCTION The Clean Air Act (CAA) establishes special goals for vis ibility in many national parks, wilderness areas, and international parks. Through the 1977 amendments to the Clean Air Act, Congress set a national goal for visibility as “the prevention of any future, and the remedying of any existing, impairment of visibility in mandatory Class I Federal areas which impairment results from manmade air pollution” (40 CFR 51.300). The goal of the Regional Haze Rule (RHR) is to achieve natural visibility conditions at 156 Federally mandated Class I areas by 2064. To achieve this goal, the RHR has set up milestone years of 2018, 2028, 2038, 2048, 2058, and 2064 to monitor progress toward natural visibility conditions. The 2000 - 2004 period has been used by states as a baseline from which to demonstrate progress toward natural visibility conditions in 2018. EPA Region 6 is presently under a court - ordered Consent Decree deadline regarding action on the Texas Regional Haze (RH) State Implementation Plan (SIP). Regional haze is linked to fine particulate matter (PM 2.5 

### ), for which EPA has a new standard. Air quality modeling is an important tool for determining whether a source can be reasonably expe cted to contribute to visibility impairment at a Class I area. ENVIRON is assisting EPA to evaluate regional haze impacts of sources in Texas that may be used to assess the Texas Regional Haze Implementation Plan. The Texas Haze analysis was built upon t he regional photochemical modeling ( ENVIRON and CERT, 200 7 ) conducted for CENRAP. In particular, the CENRAP 2002 and 2018 36 km modeling773 San Marin Drive, Suite 2115, Novato, CA 94998 P: 415 - 899 -0700 F: 415 - 899 -070 7 www.environcorp.com

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### database for CAMx was enhanced to include a 12 km grid over Texas and nearby Class I areas. The overall approach to the project includes the following steps :  Update CENRAP 2002 and 2018 modeling database to use with the latest release of CAMx (v5.4 1 )  Conduct 2002 modeling with Plume - in - Grid (PiG) and a 12 - km flexi - nest grid to provide the new 2002 baseline RH model ing  Conduct 2018 modeling with PiG and the CAMx PM Source Apportionment Technology (PSAT) for sources selected by EPA  Evaluate impact of selected sources on visibility in Class I areas  Conduct any additional future -year scenarios to access various control strategies (to be determined) This memorandum documents the new 2002 baseline modeling setup and results. 

## CAMx MODELING **APPROACH** Air quality modeling was performed with version 5.41 of the Comprehensive Air quality Model with extensions ( CAMx; ENVIRON, 20 12 ) with input data developed by CENRAP. Several features have been introduced to CAMx since CENRAP modeling, thus, many CAMx inputs had to be updated. CAMx Input development and up dates are described separately below. **2002 Annual 36 km**  **CENRAP modeling**  **database** The Texas Haze analysis was built upon the 2002 annual regional photochemical modeling database developed as part of the CENRAP ( ENVIRON and CERT, 2007 ). CENRAP developed a 2002 annual modeling database for CAMx on the 36 km unified national Reg ional Planning Organization (RPO) grid that covers the continental United States. The CENRAP modeling protocol (Morris et al., 2004) , CENRAP modeling Quality Assurance Program Plan (QAPP ; Morris and Tonnesen, 2004) , and base model evaluation ( ENVIRON and CERT, 2007) reports provide details on the development of the CENRAP 2002 36 - km annual modeling database. Emissions inputs were based on 2002 Base G Typical (Typ02G) annual emissions database. Numerous iterations of the emissions modeling were conducted using interim databases before arriving at the final Base G emission inventories (e.g., Morris et al., 2005). **Enhancement to the CENRAP 2002 Modeling Database** The CENRAP Base G 2002 36 km annual CAMx photochemical modeling database was updated to includ e a 12 km nested -grid that covers Texas and Class I areas in and near Texas including:  National Parks: Big Bend (BIBE), Guadalupe Mountains (GUMO), and Carlsbad Caverns;  Wildlife Refuges: Salt Creek (SACR) and Wichita Mountains (WIMO) ;  Wilderness Areas: Breton ( BRET), White Mountain (WHIT), Caney Creek (CACR), Upper Buffalo (UPBU), Bandeller (BAND), Hercules- Glade (HEGL), and others (see Table 1).773 San Marin Drive, Suite 2115, Novato, CA 94998 P: 415 - 899 -0700 F: 415 - 899 -070 7 www.environcorp.com

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### Figure 1 displays the 36/12 km nested grid structure used for the CAMx modeling. The locations of the Interage ncy Monitoring of Protected Visual Environments (IMPROVE) sites that includes Class I areas within and near the 12 km modeling domain are shown in Figure 2. The CAMx flexi nesting feature was used to specify a 12 km Texas fine grid within the CENRAP 36 km modeling domain. Full flexi - nesting was invoked in which CAMx internally interpolates meteorological data, gridded emissions and other inputs from the 36 km grid to the 12 km grid. Flexi - nesting does not interpolate point source emissions because exact source coordinates are known enabling each point source to be placed within the correct 36 km or 12 km grid cell.

**Figure 1. Texas RH modeling 36/12 km modeling domain and the**  **locations of the IMPROVE monitoring sites that include Class I areas, indicated by circles.**  -2736 -2304 -1872 -1440 -1008 -576 -144 288 720 1152 1584 2016 2448 -2088 -1656 -1224 -792 -360 72 504 936 1368 1800

36km: SW = (-2736,-2088) NX,NY = (148x112) DX,DY = (36x36)

12km: SW = ( -936,-1620) NX,NY = (144,108) DX,DY = (12x12) LCP Definition: (-97.0,40.0,45.0,33.0)773 San Marin Drive, Suite 2115, Novato, CA 94998 P: 415 - 899 -0700 F: 415 - 899 -070 7 www.environcorp.com

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### Figure 2. **Texas RH modeling 12 km modeling domain and the locations of the IMPROVE monitoring sites (circles) that include Class I areas.**  **Table 1. Class I areas**  **to be included in the Texas RH analysis .**  **Site State**  **Code State**  **FIPS County**  **County FIPS**  **Latitude Longitude**  **LCPX (km)**  **LCPY**

**(km) Grid**  Breton Wilderness Area LA BRET1 22 St. Bernard Parish 87 29.1189 - 89.2066 763 - 1176 12km Big Bend National Park TX BIBE1 48 Brewster County 43 29.3027 - 103.178 - 604 - 1167 12km Guadalupe Mountains TX GUMO1 48 Culberson County 109 31.833 - 104.809 - 738 - 873 12km Wichita Mountains Wilderness OK WIMO1 40 Comanche County 31 34.7323 - 98.713 - 156 - 581 12km Caney Creek Wilderness Area AR CACR1 5 Polk County 113 34.4544 - 94.1429 261 - 610 12km Upper Buffalo Wilderness Area AR UPBU1 5 Newton County 101 35.8258 - 93.203 341 -455 12km Bandelier Wilderness Area NM BAND1 35 Los Alamos County 28 35.7797 - 106.266 - 831 -424 12km Bosque del Apache Wilderness Area NM BOAP1 35 Socorro County 53 33.8695 - 106.852 - 906 - 629 12km Carlsbad Caverns NP. NM GUMO1 31.833 - 104.809 - 738 - 873 12km Gila Wilderness Area NM GICL1 35 Catron County 3 33.2204 - 108.235 - 1042 - 686 36km Pecos Wilderness Area NM WHPE1 36.5854 - 105.452 - 750 - 343 12km Salt Creek Wilderness Area NM SACR1 35 Grant County 17 33.4598 - 104.404 - 685 - 696 12km San Pedro Parks Wilderness Area NM SAPE1 35 Rio Arriba County 39 36.0139 - 106.845 - 880 - 393 12km BRET1 BIBE1 GUMO1 WIMO1 CACR1 UPBU1 BAND1 BOAP1 GICL1 SACR1 SAPE1 WHPE1

WHIT1 HEGL1 MING1 GRSA1 ROMO1773 San Marin Drive, Suite 2115, Novato, CA 94998 P: 415 - 899 -0700 F: 415 - 899 -070 7 www.environcorp.com

5 **Site State**  **Code State**  **FIPS County**  **County FIPS**  **Latitude Longitude**  **LCPX (km)**  **LCPY**

**(km) Grid**  Wheeler Peak Wilderness Area NM WHPE1 35 Taos County 55 36.5854 - 105.452 - 750 - 343 12km White Mountain Wilderness Area NM WHIT1 35 Lincoln County 27 33.4687 - 105.535 - 790 - 686 12km Hercules - Glades Wilderness Area MO HEGL1 29 Taney County 213 36.6138 - 92.9221 362 - 366 12km Mingo MO MING1 29 Stoddard County 207 36.9717 - 90.1432 606 - 312 36km Great Sand Dunes CO GRSA1 8 Saguache County 109 37.7249 - 105.519 - 744 - 217 36km Rocky Mountain National Park CO ROMO1 8 Larimer County 69 40.2783 - 105.546 - 720 65 36km 

### Preparing **Emission s Data**  CENRAP processed emission inputs using the Sparse Matrix Operator Kernel Emissions (SMOKE) version 2.3 with chemical speciation for the CB4 mechanism . Several versions of SMOKE have been released since then. This study used the latest SMOKE version 3.1 , although some SMOKE modules came from an older version to maintain compatibility with the format of data from CENRAP . All SMOKE configurations and SMOKE input files were the same as used in CENRAP with selected updates. Provided below is a summary of the emission updates made to the CENRAP database for use in this study .  Used CB05 chemical speciation profiles for a rea and point source s  Processed point source emissions in CAMx input format to prese rve stack parameters and location  Changed the earth sphere variable (IOAPI

_ ISPH) in SMOKE from 19 to 20. CENRAP SMOKE setup used IOAPI_ISPH=19 that could cause inconsistencies between point source locations and the meteorological points. IOAPI_ISPH=20 a ssumes a 6740 km earth radius consistent with MM5 and CAMx  Tagged Plume - in - Grid (PiG) for large SO 2 

### and NOx sources  Added organic aerosol precursor emissions from biogenic sources based on CENRAP BEIS CB4 emissions  Adjusted primary organic aerosol mass from POC to POA mass The c riteria used for elevated point and PiG source selection are described below: Non -Selected sources  A plume rise cutoff of 50 meter (i.e., any source having estimated plume rise lower than 50 m . was tre ated as a surface source).  NOx emissions threshold s for PiG selection varied by region : 5 tons per day (TPD) for Texas, 10 TPD for neighboring states (NM, CO, OK, AR, LA, and KS), and 20 TPD for the rest. Selected sources  All selected sources we re treated as elevated sources  PiG criteria are stack height of 50 ft (~15 m.) and NOx or SO2 emissions higher than 20 TPD773 San Marin Drive, Suite 2115, Novato, CA 94998 P: 415 - 899 -0700 F: 415 - 899 -070 7 www.environcorp.com

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### Table 2 provides an emission summary for EPA selected sources. **Table 2 . Annual emissions (TPY) of**  **EPA selected sources by pollutant in**  **the CENRAP 2002 Typical G inventory** **. Number**  **Plant Name FIPS**  **Plant ID NOX**  **CO VOC**  **SO2 PM**  **2.5 PM**  **10** 1 BIG BROWN 48161 2 7,213 20,553 134 77,860 395 933 2 BIG SPRING CARBON BLACK 48227 2 629 3,927 38 9,880 5 76 3 BORGER CARBON BLACK 48233 1 483 10,351 340 3,609 69 96 4 BORGER CARBON BLACK PLT 48233 2 822 757 3 5,148 110 242 5 COLETO CREEK PLANT 48175 2 3,563 500 60 14,289 84 173 6 FAYETTE POWER PROJECT 48149 5 19,120 1,778 231 31,798 432 1,454 7 FULLERTON GAS PLANT 48003 10 1,470 759 326 2,375 23 23 8 GIBBONS CREEK 48185 2 2,218 54 58 10,816 130 295 9 GOLDSMITH GASOLINE PLANT 48135 22 888 551 204 1,597 7 7 10 GREAT LAKES CARBON LLC 48245 23 824 43 5 9,795 178 245 11 GUADALUPE COMPRESSOR

STATION 48109 5 668 102 1 2 4 4 12 HARRINGTON STATION 48375 22 13,140 1,119 149 26,967 41 2,178 13 HOLCIM (TEXAS) LP 48139 22 4,204 5,052 627 3,167 378 379 14 HW PIRKEY POWER PLT 48203 22 4,953 30,216 58 19,476 405 799 15 KEYSTONE COMPRESSOR STN. 48495 30 2,870 619 61 0 19 19 16 KEYSTONE PLANT 48495 6 2,208 359 134 526 29 29 17 LIGNITE - FIRED POWER PLANT 48013 7 6,702 1,089 37 13,167 69 225 18 MARTIN LAKE ELECTRICAL

STATION 48401 11 18,473 47,553 257 66,402 593 881 19 MIDLOTHIAN PLANT 48139 9 4,221 763 43 2,099 115 301 20 MONTICELLO STM ELE STN 48449 3 15,924 38,339 245 86,236 1,446 3,297 21 NEWMAN STATION 48141 8 1,717 552 38 5 63 63 22 NORTH TEXAS CEMENT CO. 48139 2 2,572 418 15 4,434 349 451 23 ODESSA CEMENT PLANT48135 23 1,758 1,296 119 329 136 291 24 OKLAUNION POWER STATION 48487 10 8,711 363 14 3,751 171 392 25 PEGASUS GAS PLANT 48329 6 2,095 423 199 84 7 7 26 RELIANT ENERGY LIMESTONE 48293 10 13,461 1,021 232 29,268 496 546 27 SANDOW STEAM ELECTRIC 48331 5 7,681 4,059 67 23,327 649 735 28 SHERHAN PLANT 48195 6 2,419 727 294 537 34 34 29 SOMMERS DEELY SPRUCE PWR 48029 63 10,915 2,020 147 26,301 745 1,513 30 STREETMAN PLANT 48349 11 691 215 284 3,468 104 187 31 TEXARKANA MILL 48067 5 1,619 788 1,322 374 521 578 32 TNP ONE STEAM ELECTRIC ST 48395 13 2,400 823 2 5,088 153 318 33 TOLK STATION 48279 18 12,117 1,087 143 24,874 139 1,183 34 W A PARISH STATION 48157 5 15,903 8,027 163 60,238 992 1,026 35 WAHA PLANT 48389 2 478 271 48 3,386 42 42 36 WELSH POWER PLANT 48449 5 13,316 35,744 107 35,838 2,581 2,585 37 WORKS NO 4 48485 15 5,317 12 1 371 377 396773 San Marin Drive, Suite 2115, Novato, CA 94998 P: 415 - 899 -0700 F: 415 - 899 -070 7 www.environcorp.com

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### Preparing **Other CAMx Inputs** Meteorological data were from the MM5 prognostic meteorological model for the calendar year of 2002. The CENRAP meteorological modeling utilized data assimilation to incorporate observations into the MM5 simulations. MM5 provided CAMx with hourly input data for winds, temperature, clouds, precipitation and vertical mixing. MM5CAMx version 5.2 was used to reduce 34 MM5 vertical layers to 19 CAMx layers. Several GIS and Perl - based processors were used to prepare landcover and Leaf Area Index (LAI) input datasets for CAMx. This new landcover format is re quired in new Zhang deposition scheme in CAMx. Albedo - Haze - Ozone Inputs (AHO files) were updated to include snow cover and allow inline TUV cloud and aerosol adjustments. The photolysis rates were generated for CB05 chemistry using the updated AHO fil es. The TUV program reads the categorical values in each AHO file and creates a lookup table listing the photolysis rates for each combination of the categorical values of albedo, haze, and ozone column at various solar angles and heights above the groun d. Other inputs including boundary conditions and initial conditions were from the CENRAP database. **CAMx Model Configuration** CAMx v5.41 was chosen for this study because it was the most recent version at the time modeling task was initiated. The CAM x configuration is shown in Table 3 . CENRAP CAMx configuratio ns also are provided in Table 3 for comparison. The CAMx model was run separately for each of four quarters of 2002 using a 15 day spin up period to limit the influence of the assumed initial concentrations . **Table 3**  **. Model Configurations Options for CAMx model**  **. Science Options**  **Texas RH CENRAP**  Version Version 5.41 Version 4.40 Vertical Grid Mesh 19 Layers 19 Layers Horizontal Grids 36/12 km using two -way nesting 36 km Initial Conditions 15 days full spin - up 15 days full spin - up Boundary Conditions 2002 GEOS- CHEM day specific 3 - hour average data 2002 GEOS- CHEM day specific 3 - hour average data Sub -grid - scale Plumes PiG treatment No Plume - in - Grid (PiG) **Chemistry** Gas Phase Chemistry CB05 CB4 with isoprene updates Aerosol Chemistry ISORROPIA equilibrium ISORROPIA equilibrium Secondary Organic Aerosols SOAP SOAP Cloud Chemistry RADM -type aqueous chemistry RADM -type aqueous chemistry773 San Marin Drive, Suite 2115, Novato, CA 94998 P: 415 - 899 -0700 F: 415 - 899 -070 7 www.environcorp.com

8 **Science Options Texas RH**  **CENRAP** Meteorological Processor MM5CAMx v5.2 MM5CAMx v1 **Horizontal Transport** Eddy Diffusivity Scheme K-theory with Kh grid size dependence K-theory with Kh grid size dependence **Vertical Transport** Eddy Diffusivity Scheme K-Theory K-Theory Diffusivity Lower Limit Kzmin = 0.1 to 1.0 (Land use dependent Kzmin) Kzmin = 0.1 to 1.0 (Land use dependent Kzmin) Planetary Boundary Layer From MM5 with PBL below convective clouds raised to cloud top From MM5 Deposition Scheme Zhang Wesely **Numerics** Gas Phase Chemistry Solver Euler Backward Iterative (EBI) solver CMC fast solver Horizontal Advection Scheme Piecewise Parabolic Method (PPM scheme) Piecewise Parabolic Method (PPM) scheme Parallelization OMP - MPI OMP 

## CAMx MODELING **RESULTS** A ir quality modeling results for the 2002 baseline simulations are presented by pollutant of concern, including ozone and PM. The analysis of air quality results focus on high ozone and PM levels, i.e. maximum 8 - hour ozone and maximum 24- hour PM . Annual average levels for PM and its con stituents are also presented. Visibility analysis comparing model results to the observational data is provided at the end of this section. This project did not include a complete statistical performance evaluation. **Ozone** The annual maximum 8 - hour ozone may be susceptible to model artifacts and so we focus on the annual 4th highest 8 - hour ozone (Figure 3). The 2002 baseline shows high values of 4th 

### highest daily maximum 8 - hour ozone (above 75 ppb , the current level of the ozone NAAQS ) in several western locations such as California, Colorado and Arizona . Much of this western ozone is associated with wildfire emissions that can be identified by their smoke plumes (i.e., high organic PM). These wildfire emissions also contain high levels of NOx which is an ozone precursor. High ozone concentrations (above 100 ppb) also occur over water bodies close to major urban/industrial areas near the Great Lakes, Gulf Coast and the Northeast Seaboard, where emissions are transported over water and confined to a shallow boundary layer. Ozone exceeds 75 ppb in several urb an areas in Texas including Dallas, Houston, and San Antonio. New Orleans and Baton Rouge, Louisiana, also exceed over 75 ppb.773 San Marin Drive, Suite 2115, Novato, CA 94998 P: 415 - 899 -0700 F: 415 - 899 -070 7 www.environcorp.com

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### Figure 3 **. 4 th**  

### highest daily maximum 8**- Hour**  **o zone (ppb) from the 36** **- km simulation (left) and**  **12 -**  **km simulation (right) for the 2002 baseline. Particulate Matter**  PM 2.5 

### results are presented for daily design -value relevant measure s (98 th 

### percentile of all daily concentrations) and annual average concen trations. The baseline 8 th 

### highest 24- hour average concentrations of fine PM 2.5 

### (Figure 4) shows the highest peak values occurring in the Western United States but more uniformly high values occurring in the Eastern United States. Elevated PM 2.5 

### concentrations in the 12 km domain are seen in western Louisiana and western Arkansas. Upon inspecting emissions it appears that intense fire activities in these areas are the major cause of the high modeled PM concentrations. The causes of the high modeled PM concentrations may also be inferred from the chemical composition of the PM (shown in Appendix A). Some peaks in the Weste rn United States occur in urban areas, such as Los Angeles and Seattle (characterized by high nitrate and organic carbon) whereas others are associated with prescribed burn and wildfire emissions (indicated by high primary organic carbon). High particulate matter concentrations in the Eastern United States have large sulfate and nitrate contributions with additional contributions fr om p rimary organic PM in the south. Annual average concentrations of PM 2.5 

### and PM 10 

### (Figure 5 and Figure 6) show a similar pattern of widespread but the fire influence is less pronounced.773 San Marin Drive, Suite 2115, Novato, CA 94998 P: 415 - 899 -0700 F: 415 - 899 -070 7 www.environcorp.com

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### Figure **4 . Maximum 24** **- Hour PM2.5 (**  **μg m -**  **3 ) from the 36** **- km simulation (left) and 12** **- km**  **simulation (right) for the 2002 baseline.**

**Figure 5**  **. Annual average PM2.5 ( μg m**  **- 3**  **) from the 36 -**  **km simulation (left) and 12 -**  **km simulation (right) for the 2002 baseline.** 

**Figure 6**  **. Annual average PM10 ( μg m**  **- 3) from the 36** **- km simulation (left) and 12** **- km**  **simulation (right) for the 2002 baseline.**773 San Marin Drive, Suite 2115, Novato, CA 94998 P: 415 - 899 -0700 F: 415 - 899 -070 7 www.environcorp.com

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### Visibility The IMPROVE algorithm for estimating light extinction from PM data has been a useful tool for understanding haze in terms of the various PM components of aerosols. EPA adopted this algorithm as the basis for the regional haze metric for visibility impact calculations under the 1999 RHR. This work used the new IMPROVE algorithm (Pitchford et al., 2007) which reconstructs the light - extinction coefficient (bext, expressed in units of inverse megameters, Mm - 1) using the following equation: bext ≈

2.2 x fS 

### (RH) x [small sulfate] + 4.8 x f L

### (RH) x [large sulfate] + 2.4 x fS 

### (RH) x [small nitrate] + 5.1 x f L

### (RH) x [large nitrate] + 2.8 x [small organic mass] + 6.1 x [large organic mass]

+ 10 x [elemental carbon] + 1 x [fine soil] + 1.7 x fSS 

### (RH) x [sea salt] + 0.6 x [coarse mass] + Rayl eigh scattering (site - specific) + 0.33 x [NO2 (ppb)] The apportionment of the total concentration of sulfate compounds into the concentrations of small and large size fractions is accomplished using the following equations: [large sulfate] = [total sulfate/20] x [total sulfate], for [total sulfate] < 20 μg/m3 [large sulfate] = [total sulfate], for [total sulfate] ≥ 20 μg/m 3 [small sulfate] = [total sulfate] - [large sulfate] The similar equations are used to apportion total nitrate and total organic mass into small and large size fractions. The new algorithm contains three distinct water growth terms, designated fS

### , f L

### , and fSS 

### for the small and large sulfate and nitrate fractions, and for sea salt, respectively. Monthly average f(RH) values are used as following FLAG2010 procedure (FLAG, 2010). EPA’s visibility natural conditions guidance document lists three default natural condition values corresponding to best 20% (B20%) days, worst 20% (W20%) days, and annual average (EPA, 2003b). Our analysis calculates the 2002 visibility and compares to the measurements at Class I areas on the B20% and W20% days. Similar analysis bas ed on CMAQ simulation results was conducted by CENRAP for the worst 20% days and documented in Appendix D of the CENRAP Technical Support Document ( ENVIRON and CERT, 2007) . CENRAP analysis on the W20% days was provided here for comparison . Figures 7 - 10 demonstrate visibility comparisons at the Class I areas in Texas (i.e., Big Bend and Guadalupe Mountains) and nearby Texas (i.e., Caney Creek and White Mountain) . Additional visibility comparison for other sites can be found in Appendix B. Performance fo r the B20% days is mostly characterized by an overestimation bias; whereas the W20% days is characterized by an underestimation bias. Measurement data s how that on average sulfate773 San Marin Drive, Suite 2115, Novato, CA 94998 P: 415 - 899 -0700 F: 415 - 899 -070 7 www.environcorp.com

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### dominates light- extinction coefficient on both B20% and W20% cases, however model results show variation of dominant light- extinction co mponent . On the W20% days, underestimation of sulfate is observed across all sites. The sulfate underestimation was also seen in the CENRAP analysis. Soil performance on the B20% days at CACR and WIMO Class I areas is suspect and care should be taken in the interpretation of the visibility projections at these Class I areas.

(a) **Figure 7 (continued)**  **. Comparison of observed (left bar** **) and 2002 Base G modeled (right bar** **) daily extinction for**  **Ca ney Creek (C**  **AC R), A** **rkansas** 

### during (a) Best 20% (B **20%) and (b) Worst**  **20% (W20%) days in 2002.**  **CENRAP results on the W20% days are shown in (C).**773 San Marin Drive, Suite 2115, Novato, CA 94998 P: 415 - 899 -0700 F: 415 - 899 -070 7 www.environcorp.com

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### (b)

(c) **Figure 7 (completed)**  **. Comparison of observed (left bar** **) and 2002 Base G modeled (right**  **bar )**  **daily extinction for Ca**  **ney Creek (C AC**  **R), A rkansas**  

### during (a) **Best 20% (B 20%)**  **and (b) Worst 20% (W** **20%) days in 2002.**  **CENRAP results on the W20% days are shown in (C).**773 San Marin Drive, Suite 2115, Novato, CA 94998 P: 415 - 899 -0700 F: 415 - 899 -070 7 www.environcorp.com

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### (a)

(b) **Figure 8 (continued)**  **. Comparison of observed (left bar) and 2002 Base G modeled (right bar)**  **daily extinction for Big Bend National Park (BIBE), Texas during (a) Best 20% (B20%) and (b) Worst 20% (W20%) days in 2002. CENRAP results on the W20% days are shown in (C).** 773 San Marin Drive, Suite 2115, Novato, CA 94998 P: 415 - 899 -0700 F: 415 - 899 -070 7 www.environcorp.com

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### (c) **Figure 8 (completed)**  **. Comp arison of observed (left**  **bar ) and 2002 Base G modeled (right**  **bar )**  **daily extinction for Big Bend National Park (BIBE), Texas during ( a) Best 20% (B20%) and (b)**  **Worst 20% (W20%) days in 2002.**  **CENRAP results on the W20% days are shown in (C).**773 San Marin Drive, Suite 2115, Novato, CA 94998 P: 415 - 899 -0700 F: 415 - 899 -070 7 www.environcorp.com

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### (a)

(b) **Figure 9 (continued)**  **. Comparison of observed (left bar) and 2002 Base G modeled (right bar) daily extinction for Big Guadalupe Mountains National Park (GUMO), Texas during a) Best**  **20% (B20%) and (b) Worst 20% (W20%) days in 2002. CENRAP results on the W20 % days are**  **shown in (C).**773 San Marin Drive, Suite 2115, Novato, CA 94998 P: 415 - 899 -0700 F: 415 - 899 -070 7 www.environcorp.com

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### (c) **Figure 9 (completed)**  **. Comparison of observed (left bar** **) and 2002 Base G modeled (right bar** **) daily extinction for Big Guadalupe Mountains National Park (GUMO), Texas during**  **a) Best 20% (B20%) and (b) Worst 20% (W20%)**  **days in 2002.**  **CENRAP results on the W20% days are shown in (C).** 773 San Marin Drive, Suite 2115, Novato, CA 94998 P: 415 - 899 -0700 F: 415 - 899 -070 7 www.environcorp.com

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### (a)

(b) **Figure 10 (continued)**  **. Comparison of observed (left bar) and 2002 Base G modeled (right bar) daily extinction for Wichita Mountains Wilderness Area (WIMO), Oklahoma during a) Best**  **20% (B20%) and (b) Worst 20% (W20%) days in 2002. CENRAP results on the W20% days are shown in (C).** 773 San Marin Drive, Suite 2115, Novato, CA 94998 P: 415 - 899 -0700 F: 415 - 899 -070 7 www.environcorp.com

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### (c) **Figure 10 (completed)**  **. Comparison of observed (left bar** **) and 2002 Base G modeled (right bar** **) daily extinction for Wichita Mountains Wilderness Area (WIMO), Oklahoma during a)**  **Best 20% (B20%) and (b) Worst 20% (W20%) days in 2002.**  **CENRAP results on the W20% days are shown in (C).**  

## SUMMARY A ir quality modeling results for the 2002 baseline simulations are presented by pollutant of concern, including ozone and PM. P eak values for both ozone and PM outside of urban areas are influenced by fire emissions as indicated by high organic particulate concentrations. Overall, the air quality maps s how predicted ozone and PM concentrations within reasonable ranges . Additional analysis would have to be undertaken to examine in details the model’s ability to treat ozone and fine particulate. The model evaluation focused on the model’s ability to predi ct the components of light extinction at the Class I areas . Similar visibility analysis by CENRAP concluded that the CMAQ 2002 36 km model appears to be good enough to make future -year projections for changes in SO4, NO3, EC and OMC at the rural Class I areas. The CAMx 2002 model appears to be comparable to the CENRAP 2002 model on the worst 20% days. Underestimation bias of sulfate is seen in both simulations with a larger bias seen in this study. Performance for Soil and especially CM is suspect and ca re should be taken in interpreting these modeling results.773 San Marin Drive, Suite 2115, Novato, CA 94998 P: 415 - 899 -0700 F: 415 - 899 -070 7 www.environcorp.com

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## REFERE **N C**  **ES** ENVIRON. 20 12 . “User’s Guide – Comprehensive Air- quality Model with extensions, Version 5 . 40.” ENVIRON International Corporation, Novato, California. (Available at http://www.camx.com ). ENVIRON and CERT. 2007. “Technical Support Document for CENRAP Emissions and Air Quality Modeling to Support Regional Haze State Implementation Plans”, prepared for the Central Regional Air Planning Association, prepared by ENVIRON International Corporation, and the University of California, Riverside. September 12. EPA. 2 003 . Guidance for Estimating Natural Visibility Conditions under the Regional Haze Rule. EPA-454/B -03 -005. U.S. Environmental Prot ection Agency, Research Triangle Park, NC. FLAG. 2010. Federal Land Managers’ Air Quality Related Values Work Group (FLAG) Phase I report - Revised (2010). Natural Resource Report NPS/NRPC/NRR — 2010/232 Morris, R.E., G.E. Mansell, B. Koo, G. Tonnesen, M. Oma ry and Z. Wang. 2004. Modeling Protocol for the CENRAP 2002 Annual Emissions and Air Quality Modeling, Draft 2.0. ( http://pah.cert.ucr.edu/aqm/cenrap/docs/CENRAP_Draft2.0_Modeling_Protocol_1208 4.pdf). December 8. Morris, R.E. and G. Tonnesen. 2004. Quality Assurance Project Plan (Draft) for Central Regional Air Planning Association (CENRAP) Emissions and Air Quality Modeling. ( http://pah.cert.ucr.edu/aqm/cenrap/docs/CENRAP_QAPP_Nov_24_2004.pdf). December 23. Morris, R.E., A. Hoats, S. Lau, B. Koo, G. Tonnesen, C-J. Chien and M. Omary. 2005. Air Qua lity Modeling Analysis for CENRAP – Preliminary 2002 Base Case CMAQ and CAMx Modeling of the Continental US 36 km Domain and Model Performance Evaluation. ENVIRON International Corporation, Novato, California. April 30. Pitchford, M.L., Malm, W.C., Schicht el, B.A., Kumar, N., Lowenthal, D., and Hand, J.L. 2007. Revised algorithm for estimating light extinction from IMPROVE particle speciation data. Journal of the Air and Waste Management Association . 57, 1326 - 1336.

# APPENDIX A

**Annual Average PM Constituents from the CAMx 2002 Base Case results**773 San Marin Drive, Suite 2115, Novato, CA 94998 P: 415 - 899 -0700 F: 415 - 899 -070 7 www.environcorp.com

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## Appendix A **: Annual Average PM**  **Constituents from the CAMx 2002 Base Case** 

**results**

(a) Sulfate

(b) Nitrate

(c) Ammonium

### (d) Organic aerosols

(e) Elemental Carbon

(f) Secondary organic aerosols

### (g) Other fine particulates and fine crustal materials

# APPENDIX **B Visibility Analysis for 2002 Typical Base G Emission Scenario** 773 San Marin Drive, Suite 2115, Novato, CA 94998 P: 415 - 899 -0700 F: 415 - 899 -070 7 www.environcorp.com

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## Appendix B **: Visibility Analysis for 2002 Typical Base G Emission Scenario** 

(a )

(b ) **Figure B** **- 1**  **. Comparison of observed (left bar** **) and 2002 Base G modeled (right bar** **) daily extinction for**  **Upper Buffalo Wilderness (**  **UPBU ),**  **Arkansas during**  **(a) Best 20% (B 20%)**  **and (b) Worst 20% (W20%)**  **days in 2002.**

### (a)

(b) **Figure B -** **2. Comparison of observed (left bar** **) and 2002 Base G modeled (right bar** **) daily extinction for Hercules** **- Glades Wilderness (HUGL),**  **Missouri during (a) Best 20% (B20%) and**  **(b) Worst 20% (W20%) days in 2002.**

### (a)

(b) **Figure B -** **3. Comparison of observed (left bar** **) and 2002 Base G modeled (right bar** **) daily extinction for**  **Salt Creek Wilderness (SACR** **), New Mexico**  **during (a) Best 20% (B20%) and (b) Worst 20% (W20%) days in 2002.** 

### (a)

(b) **Figure B -** **4. Comparison of observed (left bar** **) and 2002 Base G modeled (right bar** **) daily extinction for**  **White Mountains Wilderness (** **WHIT), New Mexico during (a) Best 20% (B20%)**  **and (b) Worst 20% (W20%) days in 2002.**

### (a)

(b) **Figure B -**  **5. Comparison of observed (left bar** **) and 2002 Base G modeled (right bar** **) daily extinction for Bosque del Apache Wilderness (BOAP), New Mexico during (a) Best 20% (B20%)**  **and (b) Worst 20% (W20%) days in 2002.**

### (a)

(b) **Figure B -** **6 . Comparison of observed (left**  **bar ) and 2002 Base G modeled (right**  **bar ) daily**  **extinction fo r**  **Bandelier Wilderness Area (**  **BAND), New Mexico during (a) Best 20% (B20%)**  **and (b) Worst 20% (W20%) days in 2002.**

### (a)

(b) **Figure B -** **7 . Comparison of observed (left**  **bar ) and 2002 Base G modeled (right**  **bar ) daily**  **extinction for Breton Wilderness**  **( BRET), Louisiana**  **during (a) Best 20% (B20%) and (b) Worst 20% (W20%) days in 2002.**