### Draft Final Modeling Protocol



# CALMET/CALPUFF Protocol for BART Exemption Screening Analysis for Class I Areas in the
Western United States

Prepared for:

Western Regional Air Partnership Air Quality Modeling Forum

c/o Tom Moore

Western Governors’ Association

Prepared by:

Western Regional Air Partnership Air Quality Modeling Forum

Regional Modeling Center

Gail Tonnesen and Zion Wang University of California at Riverside

Ralph Morris, Abby Hoats and Yiqin Jia

ENVIRON International Corporation

August 15, 2006

ENVIRON, 101 Rowland Way, Suite 220, Novato, CA 94945 415.899.0700August 15, 2006

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# Table of Contents

FOREWORD....................................................................................................................... ......... iv

1. INTRODUCTION................................................................................................................ 1-1

1.1 Emissions Used.......................................................................................................... 1- 2 1.2 Visibility Calculations ............................................................................................... 1-3

2. EXTRACTION OF MM5 DATA FO R CALMET/CALPUFF MODELING................ 2-1

3. CALMET/CALPUFF MODELING METHODOLOGY ................................................ 3-1

3.1 CALMET/CALPUFF Model Selection ..................................................................... 3-2

3.1.1 CALMET ............................................................................................................. 3-2 3.1.1.1 CALMET Modeling Domain........................................................................ 3-3

3.1.1.2 CALMET Performance Evaluation ............................................................ 3-13

3.1.1.3 Terrain......................................................................................................... 3-13

3.1.1.4 Land Use ..................................................................................................... 3-13 3.1.1.5 CALMET ZFACE and ZIMAX Settings.................................................... 3-14 3.1.1.6 CALMET Options and Comparison with Regulatory Default Settings........................................................................ 3-14

3.1.2 CALPUFF.......................................................................................................... 3-18 3.1.2.1 Receptor Network and Class I Federal Areas............................................. 3-18 3.1.2.2 CALPUFF Meteorology ............................................................................. 3-18 3.1.2.3 CALPUFF Modeling Domains................................................................... 3-18

3.1.2.4 CALPUFF Parameter Summ ary and Comparison with Regulatory Defaults ............................................................................ 3-19

3.1.2.5 Chemical Mechanism.................................................................................. 3-22 3.1.2.6 Ammonia Assumptions............................................................................... 3-22 3.1.2.7 Ozone Assumptions .................................................................................... 3-23 3.1.3 CALPOST Settings and Visi bility Post-Processing .......................................... 3-23

4. ALASKA CALPUFF BART MODELING ....................................................................... 4-1

4.1 CALMET Modeling................................................................................................... 4-2 4.2 CALPUFF Modeling ................................................................................................. 4-3

5. RESULTS ..................................................................................................................... ........ 5-1

6. REFERENCES.................................................................................................................. ... 6-1August 15, 2006

G:\WRAP RMC\BART\Protocol\Draft_Aug15_2006\WRAP_RMC_BART_Protocol_Aug15_2006.doc ii TABLES

Table 2-1. MM5 model options for the MM5 simulations to be used in the WRAP BART screening modeling............................................................ 2-2

Table 3-1. Definition of St ate CALMET/CALPUFF modeling domains using the RPO LCC projections based on an origin at (-97 ° , 40 ° ) and true latitudes at 33 ° and 45 ° ........................................................ 3-4 Table 3-2. CALMET options and comp arison of proposed values with EPA regulatory default settings as given by Atkinson and Fox (2006), deviations fro m EPA recommended defaults are indicated by bold text .................................................................................. 3-15 Table 3-3. CALPUFF options and comp arison of EPA regulatory modeling default values with proposed values for the RMC BART screening analysis... 3-19

Table 4-1. Definition of the CALM ET/CALPUFF Alaska BART modeling domain using a Lambert Conformal Conic (LCC) map projection. .................... 4-2

Table 4

− 2. Locations of the 5 surface me teorological sites used in the Alaska BART CALMET/CALPUFF modeling.................................................. 4

− 2

FIGURES

Figure 2-1. Relationship of four MM5 extraction window domains for State CALPUFF modeling (AZ, MT, NM, NV, SD and UT)

and Class I areas................................................................................................... 2-4 Figure 3-1a. Proposed CALMET/ CALPUFF modeling domain, Class I area receptors (green) and observed surface meteorological sites for Arizona.......................................................................... 3-5 Figure 3-1b. Proposed CALMET/ CALPUFF modeling domain, Class I area receptors (green) and observed surface monitoring sites (purple triang les) for Montana (RMC currently does not have any plans for modeling Montana BART sources). ....................... 3-6 Figure 3-1c. Proposed CALMET/ CALPUFF modeling domain, Class I area receptors (green), observed surface meteorological sites (pur ple triangles) and potential BART-eligible source locations (red circles) for New Mexico........................... 3-7 Figure 3-1d-1. Proposed CALMET/CALP UFF modeling domain and Class I area receptors (green) and observed surface meteorological sites (purple triangles) for Nevada....................................................................... 3-8 Figure 3-1d-2. Proposed CALPUFF modeli ng domain for Northern potential BART-eligible sources near Reno a nd Class I area receptors (green)................. 3-9 Figure 3-1d-3. Proposed CALPUFF modeli ng domain for Southern potential BART-eligible sources near Las Vega s and Class I area re ceptors (green) ...... 3-10 Figure 3-1e. Proposed CALMET/CALPU FF modeling domain and Class I area receptors (green), observed surface meteorological sites (purple triangles) and potential BART-eligible source locations (red circles) for South Dakota ............................................................ 3-11 Figure 3-1f. Proposed CALMET/CA LPUFF modeling domain and Class I area receptors (green) and observed surface meteorological sites (purple triangles) for Utah ......................................................................... 3-12August 15, 2006

G:\WRAP RMC\BART\Protocol\Draft_Aug15_2006\WRAP_RMC_BART_Protocol_Aug15_2006.doc iii Figure 3-2. Land use categories tabl e from CALMET User's Guide ................................... 3-13 Figure 4-1. Locations of potential BART-eligible sources (red dots) and Class I areas (green regions) in Alaska......................................................... 4-1 Figure 4-2. Alaska BART CALM ET/CALPUFF modeling domain showing the potential BART -eligible sources (red dots) and

Denali and Tuxedni Cl ass I area receptors .......................................................... 4-3August 15, 2006

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# FOREWORD

This document is a draft final Modeling Protocol th at discusses the procedures to be used by the Western Regional Air Partners hip (WRAP) Regional Modeling Center (RMC) for developing MM5 databases to support CALMET/CALPUFF modeling and for conducting BART screening exemption modeling using the CALMET/CALPU FF modeling system for six WRAP region States: Alaska; Arizona; New Me xico; Nevada; Utah; and South Da kota. Processed MM5 data will also be provided to Montana who w ill conduct their own CALMET/CALPUFF BART modeling.

This Modeling Protocol is ba sed on the BART CALPUFF Modeli ng Protocol prepared by the Colorado Department of Public Health a nd Environment (CDPHE) Air Pollution Control Division (APCD) (CDPHE, 2005). We would like to thank Chuck Machovec and others at the CDPHE/APCD for allowing us to use their Modeli ng Protocol as a starting point for the WRAP RMC Modeling Protocol.

In addition to addressing different States, po tential BART-eligible sources and Class I areas,

there are several other differences betw een the proposed CALMET/CALPUFF modeling approach in this Modeling Prot ocol versus those proposed by the CDPHE (CDPHE, 2005) and other WRAP States (e.g., NDDOH, 2005). For exam ple, we are proposing to use the three years of 2001, 2002 and 2003 for which 36 km MM5 data ar e available, whereas the CDPHE used the three years of 1996, 2001 and 2002. One major change in this revised draft Modeling Protocol compared to previous draft Modeling Protocol s prepared by the WRAP RMC is we are now using meteorological observations along with the MM5 data as input to the CALMET/CALPUFF modeling system. In previous draft Modeling Protocols we proposed to operate CALMET using just the MM5 data without observed meteorological observations (i.e., the NOOBS mode). Comments received from EP A and Federal Land Managers (FLMs) noted that running CALMET/CALPUFF with meteorological observati ons was preferred and more conservative. Thus, meteorolog ical observations were acquired and processed for input into CALMET for the WRAP RMC BART screening exemption modeling.

The resultant CALMET/CALPUFF m odeling databases developed under this work effort will be

made available to the affected States. If the Stat es or others wish to us e or enhance the databases (e.g., high grid resolution, addition of more meteorological observat ions, etc.), they may obtain

the databases from the States.August 15, 2006

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# 1. Introduction

Federal law requires Best Ava ilable Retrofit Technology (BART) for any BART-eligible source that ‘‘emits any air pollutant wh ich may reasonably be anticipated to cause or contribute to any impairment of visibility” in any mandatory Class I federal area. Pursuant to federal regulations, states have the option of exempting a BART-elig ible source from the BART requirements based on dispersion modeling demonstrat ing that the source cannot reason ably be anticipated to cause or contribute to visibility impairment in a Class I area.

According to 40 CFR Part 51, Appendix Y (EPA BART Guidelines; EPA, 2005), a BARTeligible source is considered to “contribute” to vi sibility impairment in a Class I area if the

modeled 98 th percentile change in de civiews is equal to or gr eater than the “contribution threshold.” Any BART-eligible source determined to cause or contribute to visibility impairment in any Class I area is subject to BART. Th e EPA BART Guidelines suggest a contribution threshold of 0.5 change in deciview be used.

The WRAP RMC is processing 36 km MM5 data for the three years of 2001, 2002 and 2003 to support CALMET/CALPUFF modeling for six WRAP region States in the contiguous United States: Arizona; Montana; New Mexico; Nevada; Utah; and South Dakota. The processing of MM5 data to support CALMET/CALPUFF modeli ng for these six WRAP region States is

discussed in Section 2. The WRAP RMC will co nduct BART screening modeling for five of these States using the CALMET/CALPUFF modeling system and the 2001, 2002 and 2003 MM5 using procedures discussed in S ection 3. The RMC will also conduct CALMET/CALPUFF BART screening modeling fo r sources in Alaska using a 2002 MM5 and

CALMET/CALPUFF databases that is discussed in Section 4.

The WRAP RMC will apply CALPUFF with three ye ars of meteorological data (one year for Alaska) and report on the 24-hour cha nge in visibility (delta-deciview, Δ dv) from potential BART-eligible sources at mandatory Federal Cl ass I areas in and near each of the States

modeled. The maximum and 98 th percentile estimated 24-hour change in visibility ( Δ dv) will be summarized for each potential BART-eligible source and each Class I area under study. Spreadsheets of 24-hout average change in deci view from each potential BART-eligible source and each Class I area will be provided to the States in question who will determine which potential BART-eligible sources in their States are subject to BART.

The WRAP RMC will use this protocol for the in itial subject-to-BART m odeling for the States indicated above. However, it is up to the Stat es themselves to make the subject to BART determination. Additional modeling performed by the States or source operators may supersede the screening results from the WRAP RMC. Subsequent modeling should use modeling techniques consistent with the EPA BART Guidelines (EPA, 2005). The CALMET/CALPUFF modeling databases developed by the WRAP RMC w ill be provided to the affected States if

desired.August 15, 2006

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### 1.1. Emissions Used

According to the EPA BART Guidelines: “ The emissions estimates used in the models are intended to reflect steady-state operating conditions during periods of high capacity utilization. We do not generally recommend that emission s reflecting periods of start-up, shutdown, and malfunction be used, as such emission rate s could produce higher t han normal effects than would be typical of most facilities. We recomme nd that States use the 24 hour average actual emission rate from the highest emitting day of the meteorological peri od modeled, unless this rate reflects periods start- up, shutdown, or malfunction .” (EPA, 2005)

Short-term emission rates ( ≤ 24-hours) should be mode led since visibility impacts are calculated for a 24-hour averaging period. SO 2 , NOx, and PM10 (including condens ible and filterable direct PM10) should be modeled from all BART-eligible uni ts at the facility. States will provide the

WRAP RMC with the source characteristics a nd emission rates to be used in the BART screening analysis. Source character istics that must be included are:

• Stack Location (e.g., latit ude/longitude, UTM, etc.)

• Stack Height (e.g., m or ft)

• Stack Diameter (e.g. m or ft)

• Exit Velocity (e.g., m/s or ft/s) or Flow Rate (e.g., m 3 /s or ft 3 /s)

Emission rates that must be included include the following (e.g., gm/s, tons/day. tons/year):

• SO2

• NOx (as NO2)

• Primary PM10 In addition, the PM10 emissions should be broken down by PM species as follows:

• SO4 (Sulfate, included primary H 2 SO 4 )

• NO3 (Nitrate)

• EC (Elemental Carbon)

• OC (Organic Carbon)

• PMF (Other PM 2.5 or Soil)

• PMC (Coarse PM, PM 2.5-10 ) However, in reality most States provided PM emission estimates for their potential BARTeligible sources as total PM 10 without speciation. In this case we will model the PM 10 as PM 2.5 and summarize the PM contribution to light extinction for the highest visibility impairment days and it will be up to the States to justify perf orming the BART exemption screening analysis without speciating the PM emissions (see Sec tion 1.2 for extinction characteristics of the different components of PM).

Maximum actual 24-hour emission rates may not be generally available for all sources. It is up to the States to provide the WRAP RMC with the emission rates they wish the RMC to use. The CDPHE provided the following guidance in thei r BART Modeling Protocol on what emission rates the CDPHE felt was acceptable for CA LPUFF BART exemption modeling (CDPHE, 2005):

• Short-term ( ≤ 24-hours) allowable emission rates (e .g., emission rates calculated using the maximum rated capacity of the source).

• Federally enforceable short-term limits ( ≤ 24-hours).

• Peak 24-hour actual emission rates (or calculate d emission rates) from the most recent 3 to 5 years of operation that account for “high capacity utilization” during normalAugust 15, 2006

G:\WRAP RMC\BART\Protocol\Draft_Aug15_2006\WRAP_RMC_BART_Protocol_Aug15_2006.doc 1-3 operating conditions and fuel/material flexibil ity allowed under the source's permit. In

situations where a unit is allowed to use more than one fuel, the fuel resulting in the highest emission rates should be used for the modeling, even if that fuel has not been used in the last 3 to 5 years.

If short-term rates are not avai lable, emissions rates based on averaging periods longer than 24- hours are acceptable only in cases where the modeli ng shows that the source has impacts equal to or greater than the contri bution threshold (CDPHE, 2005).

The WRAP region States reviewing the visibi lity impacts will make their own opinion on the interpretation of the visibility modeling results in the case emi ssion rates with longer averaging times than 24-hours are used. As noted above, if the visibility impact at a Class I area exceeds the 0.5 dv using longer averaging time emissions, then the 0.5 dv threshold would also be exceeded using the maximum 24-hour average emi ssions. If on the other hand, the visibility impacts due to the source at all Class I areas and all days are substa ntially below the 0.5 dv threshold, the State may be able to justify the de termination that the source does not contribute significantly to visibility impa irment at any Class I area.



### 1.2. Visibility Calculations

The CALPUFF modeling of the potential BART-eligible sources at Class I areas will potentially produce estimated 24-hour concentrations of SO 4 , NO 3 , EC, OC, PMF and PMC concentrations at a set of receptors that cove r the Class I area. These concentration estimates need to be converted to light extinction. Th e general theory for performing vi sibility calculations with the CALPUFF modeling system is described in several documents, including:

 “Interagency Workgroup on Air Qualit y Modeling (IWAQM) Phase 2 Summary Report and Recommendations for Modeli ng Long Range Transport Impacts” (IWAQM, 1998)

 “Federal Land Manager’s Air Quality Re lated Values Workgroup (FLAG): Phase I Report” (FLAG, 2000)

 “A User's Guide for the CALPUFF Dispersion Model” (Scire, 2000)

 IMPROVE documents such as “Spatial and Seasonal Patterns and Temporal Variability of Haze and its constituents in the United State” (Malm et al., 2000)

In general, visibility is charac terized either by visual range (the greatest distance that a large object can be seen) or by the light extinction coefficient, which is a measure of the light attenuation per unit distance due to scattering and absorpti on by gases and particles.

Visibility is impaired when light is scattered in and out of the line of si ght and by light absorbed along the line of sight. The lig ht extinction coefficient (b ext ) considers light extinction by scattering (b scat ) and light extinction by absorption (b abs ):

b ext = b scat + b abs

The scattering components of extinction can be represented by these components:

 light scattering due to air mol ecules = Rayleigh scattering = b rayleigh

 light scattering due to particles = b spAugust 15, 2006

G:\WRAP RMC\BART\Protocol\Draft_Aug15_2006\WRAP_RMC_BART_Protocol_Aug15_2006.doc 1-4 The absorption components of extinction can be represented by these components:

 light absorption due to gaseous absorption = b ag

 light absorption due to particle absorption = b ap

Modeled concentrations are converted to light extinction using the IMPROVE reconstructed mass extinction equation. This equation accounts for both light scattering and light absorption due to particles. The current IMPROVE r econstructed mass extinc tion equation does not account for light absorption due to gases. The IMPROVE Steering Committee has recently endorsed a new IMPROVE equation that includes li ght absorption due to gases, but EPA BART Guidelines and this Modeling Protocol will use the current IMPROVE equation.

Particle scattering, b sp , can be expressed by its components:

b sp = b SO4 + b NO3 + b OC + b SOIL + b Coarse

where:

 b SO4 = scattering coefficient due to sulfates = 3[(NH 4 ) 2 SO 4 ]f(RH)

 b NO3 = scattering coefficient due to nitrates = 3[NH 4 NO 3 ]f(RH)

 b OC = scattering coefficient due to organic aerosols = 4[OC]

 b SOIL = scattering coefficient due to fi ne particles = 1[Soil] = 1[PMF]

 b Coarse = scattering coefficient due to coar se particles = 0.6[Coarse Mass] = 0.6[PMC]

Particle absorption from soot is defined as:

 b ap = absorption due to elem ental carbon (soot) = 10[EC]

The concentration values (in brackets) are e xpressed in micrograms per cubic meter. The

numeric coefficient at the be ginning of each equation is the dry scattering or absorption efficiency in meters-squared per gram (also ca lled the extinction coefficient). Sulfate (SO 4 ) and nitrate (NO 3 ) are assumed to be completely neutralized by ammonium (NH 4 ). Both SO 4 and

NO 3 are assumed to by hygroscopic and take up water under conditions of higher moisture, which affects their scattering properties. This is accounted for by the f(RH) term that is the relative humidity adjustment factor.

The total atmospheric extinction (b ext ) can be expressed as:

b ext = b SO4 + b NO3 + b OC + b SOIL + b Coarse + b ap + b rayleigh

In this equation, the sulfate (SO4 ) and nitrate (NO3) components are referred to as hygroscopic components because the extinction coeffici ent depends upon relative humidity. The other components are assumed to be non-hygroscopic.

The variation of the effect of relative humi dity on the extinction coefficients for SO 4 and NO3 can be determined in several ways. Accordi ng to the EPA BART Guidelines, monthly f(RH) values should be used (EPA, 2003a,b).

The CALPUFF modeling techniques in this protocol will provid e ground level concentrations of visibility impairing pollutants. The concentrat ion estimates from CALPUFF are used with the previously shown equations to calc ulate the extinction coefficient.August 15, 2006

G:\WRAP RMC\BART\Protocol\Draft_Aug15_2006\WRAP_RMC_BART_Protocol_Aug15_2006.doc 1-5 As described in the IWAQM Phase 2 Report, the change in visibility is compared against background conditions. The delta-deciview, Δ dv, value is calculated from the source’s contribution to extinction, b

source , and background extinction, b background , as follows:

Δ dv = 10 ln ((b background + b

source )/ b background )

Here the background extinction (b background ) is supposed to represent Natural Conditions (i.e., no man made impairment). The EPA BART Guidelines references that Natural Conditions be based on EPA’s “Guidance for Estimating Natural Conditions under the Regional Haze Rule” (EPA, 2003a). This guidelines lists three sets of Na tural Conditions corresponding to Annual Average, Best 20% Days and Worst 20% Days. EPA initially stated that the Natural Visibility Conditions corresponding to the Best 20% Days should be used for BART modeling (EPA, 2005). However, the use of the B20% Natural Conditi ons was challenged by the Utility Air Regulatory Group (UARG) and now EPA will a llow States to use the Annual Average Natural Conditions in their subject to BART assessment (Paise, 2006a,b). For the WRAP RMC CALPUFF BART exemption screening modeling, change s in visibility at Class I ar ea will be calculated using all three types of EPA default Natural Conditions (B20%, Annual Average and W20%) so that the States can understand the sensitivity of the results to this assumpti on and it is up to the States to select what Natural Conditions they believe are appropriate for their subject to BART

determinations.August 15, 2006

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# 2. Extraction of MM5 Data For CALMET/CALPUFF Modeling

Three years of 36 km MM5 data from 2001, 2002 and 2003 will be processed for the CALMET/CALPUFF modeling system and six States in the west ern U.S.: Arizona; Montana; New Mexico; Nevada; Utah; and South Dakota. The MM5 data were carried out by different groups as follows:

2001 36 km MM5 data developed by Alpine Geophysics, LLC for the EPA and was used

in the CAIR and CAMR modeling (McNalley, 2003);

2002 36 km MM5 data developed by the WRAP RMC for the WRAP regional modeling (Kemball-Cook et al., 2004); and

2003 36 km MM5 data developed by the Midwest RP O (MRPO/LADCO) for their regional modeling (Baker, 2004a,b).

The 2002 36km MM5 data have been more exte nsively analyzed and tested for optimal configuration by the RMC for performance in the WRAP region. The 2001 and 2003 MM5 datasets have not been similarly evaluated in as detailed fashion for their accuracy and performance in the WRAP region.

In addition, a separate 2002 MM5 database deve loped by the WRAP RMC will be used for the

Alaska BART CALPUFF modeli ng analysis (see Section 4).

Table 2-1 summarizes the model options used in th e MM5 simulations that are being used in the CALMET/CALPUFF BART screening modeling. For the 2001, 2002 and 2003 continental US

MM5 simulations the same 36 km Lambert Confor mal Projection grid was used. Whereas, due to the much higher latitudes, the Alaska simulati ons used a Polar Stereographic grid projection.

The Pleim-Xiu LSM module was used for the c ontinental U.S. simulations, where for the 2002

and 2003 runs the MM5 simulations were conducted in 51⁄2 day segments with a cold start and 12 hours of spin up time, but for the 2001 run each MM5 run segment soil mois ture was initialized off of the previous run segment (but not soil temp erature which was found to lead to a cold bias in the runs). During the summer the Alaska MM5 simulations used the OSU/Noah LSM

module. However the winter Alaska MM5 simu lations was run with the “sea ice” turned on which does not support the OSU LSM so the simpler 5-layer LSM was used.August 15, 2006

G:\WRAP RMC\BART\Protocol\Draft_Aug15_2006\WRAP_RMC_BART_Protocol_Aug15_2006.doc 2-2 Table 2-1. MM5 model options for the MM5 simulations to be used in the WRAP BART screening modeling.

Continental US Alaska 2002

Model Option 2001 2002 2003 Summer Winter
Source Coordinate System Lambert Lambert Lambert Polar Polar

Grid Resolution 36 km 36 km 36 km 15 km 15 km

Land Surface Module Pleim-Xiu 1 Pleim-Xiu Pleim-Xiu OSU/Noah 5-Layer Planetary Boundary Layer ACM ACM ACM ETA ETA

Radiation RRTM RRTM RRTM RRTM RRTM Moist Physics Reisner II Reisner I Reisner I Reisner II Reisner II
Cumulus KF 1 BM KF 1 Grell Grell

Shallow Convection None None None None None

Sea Ice No No No No Yes Analysis Nudging
Surface None U/V None None None
Aloft U/V/T/Q U/V/T/Q U/V/T/Q U/V/T/Q U/V/T/Q Observation Nudging

Surface None U/V None U/V U/V

1 The 2001 Pleim-Xiu LSM simulation used continuous moisture, whereas 2002 and 2003 used cold starts with 12

hours initialization.

The processed MM5 data for CALPUFF modeling pr oduce quite large files. Thus, we wish to

define smaller domains for each of the States that n eed the data in order for the file sizes and data transfers to be more manageable. Th e MM5 data must completely cover the CALMET/CALPUFF modeling domains. They need to include the State of in terest, plus Class I areas in nearby States with su fficient buffer between the Clas s I areas and the boundaries (e.g., 50 km) to assure that CALPUFF puffs are not eliminated due to the centerline leaving the domain while the puff is still ha ving a significant visibility imp acts at a Class I area. Based on the States that require MM5 processing assistan ce, we have identified the following four MM5

extraction domains:

Arizona-New Mexico

Nevada-Utah

Montana

South Dakota

MM5 Windowed Domains

Figure 2-1 displays the four windowed domains where MM5 data will be processed for CALMET/CALPUFF modeling. Also displayed in Figure 2-1 are th e locations of the States (source regions) and Class I area (recep tor regions) in the western U.S.August 15, 2006

G:\WRAP RMC\BART\Protocol\Draft_Aug15_2006\WRAP_RMC_BART_Protocol_Aug15_2006.doc 2-3 Arizona-New Mexico

The Arizona-New Mexico MM5 window domain is centered on the two States (Figure 2-1). It extends west to include the Sequoia and Kings Canyon National Parks and Dome Land

Wilderness in the north as well as several So uthern California Class I areas. The northern boundary of the Arizona-New Mexico MM5 window domain is sufficiently north to include

Class I areas in southern Utah and Colorado with a 50 km buffer. The eastern boundary was extended to include all of New Mexico; original ly it was extended as far east to include the

Wichita Mountains Class I area in Oklahoma but comments received from the FLMs were that this was unnecessary. We also considered pus hing the southern boundary sufficiently far to include Big Bend National Park, however any BART source impact at Big Bend would likely have much higher impacts at the closer southe rn New Mexico and Arizona Class I areas (e.g., Guadalupe and Carlsbad Caverns). Consequent ly, the southern boundary was terminated north of Big Bend National Park.

Nevada-Utah

The Nevada-Utah MM5 window domain includes th e two States and extends to the: (1)

southwest to include the Southe rn California Class I areas; (2) northwest to include the

northeastern California a nd some south-central Oregon Class I areas; (3) north to include the Sawtooth Wilderness Area; (4) northeast to include Wind Rive r and Eton Class I areas in Wyoming; and (5) to the east and southeast to include Class I areas in the Colorado Rocky

Mountains and San Pedro Parks Class I area in New Mexico.

Montana

The Montana MM5 window domain includes all of Montana and a ll Class I areas in Idaho and some in eastern Washington and Oregon. The Sout hern boundary is sufficient south to include all of the Wyoming Class I areas. The eastern boundary was placed so that the Theodore Roosevelt, North Dakota and Wind Cave and Ba dlands, South Dakota Class I areas could be included. The State of Montana also provide d the definitions of their CALPUFF modeling domain that stretched west-east from longitu de –177 to –103 degrees and south-north from latitude 44 to 49.5 degrees. The Montana MM5 window domain was made sufficient large to encompass these dimensions.

South Dakota

The South Dakota MM5 window domain had to be made fairly large due to distance between the State and Class I areas in nearby States. The western boundary was sufficiently west to include eastern Montana and western Wyoming Class I ar eas. Southern Boundary stretched down to

include the Mount Zirkel Colora do Class I area. And the norther n and eastern boundaries were defined so that the Voyageurs and Boundary Wate rs, Minnesota Class I ar eas could be included.August 15, 2006

G:\WRAP RMC\BART\Protocol\Draft_Aug15_2006\WRAP_RMC_BART_Protocol_Aug15_2006.doc 2-4 Figure 2-1. Relationship of four MM5 extraction window domains for State CALPUFF modeling (AZ, MT, NM, NV, SD and UT) and Class I areas.August 15, 2006

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# 3. CALMET/CALPUFF Modeling Methodology

For the WRAP RMC BART exemption screeni ng modeling, we will follow the EPA BART Guidelines (EPA, 2005) and the applicab le CALMET/CALPUFF m odeling guidance (e.g., IWAQM, 1998; FLAG, 2000; EPA, 2003c) including EPA’s recent March 16, 2006 memorandum: “Dispersion Coefficients for Re gulatory Air Quality Modeling in CALPUFF” (Atkinson and Fox, 2006). This memorandum was written by the EPA Office of Air Quality and Planning Standards (OAQPS) Model Clearing Hous e Director in response to questions from EPA Region 4 on what constitutes the regulat ory version of CALP UFF and recommended CALPUFF options for BART modeling in their region. Consequently, the CALMET/CALPUFF modeling recommendations in the EPA memorandu m (Atkinson and Fox, 2006) are followed in this Modeling Protocol, with the following exceptions (more details on these exceptions are provided in Sections 3.1.1.6 and 3.1.2.4):

• We propose to use the latest version of CALPUFF (Version 6 date d April 2006) rather than the “EPA Approved Version”;

• A maximum mixing height of 4,500 m AGL w ill be specified rather than the EPA

recommended default maximum mixi ng height value of 3,000 m AGL;

• The modeling domains will be based on a La mbert Conformal Conic (LCC) projection consistent with the RPO modeling rather than the EPA default;

• Compatible values for the CALMET IEXTRP and RMIN2 parameters will be used;

• The number of emitted and modeled species will depend on the level of detail on emissions provided by the States rather than the EPA default 3 and 5 species, respectively; and

• A background ammonia value of 1 ppb will be used in the CALPUFF modeling (0

− 1 ppb for Alaska) rather then the 10 ppb EPA default.

• Water land use will be specified and no spatial averaging of temperatures will be performed (IAVET=0).

The WRAP RMC will perform an initial subject-t o-BART screening analysis modeling using the procedures in this Modeling Protocol and provide the results to the affected States. However, the WRAP RMC initial modeling may be superseded by additional modeling performed by the States or source operators.

Relevant guidance suggests that the CALPUFF model is generally applicable at distances from 50 km to 300 km downwind and may be used for distance less than 50 km when complex flows exist on a case by case basis (IWAQM, 1998; FLAG 2000; EPA, 2003c). Class I areas in the west generally are located in complex terrain resulting in complex flow s. Consequently, theBART screening modeling conducted by the RMC will include results for potential BARTeligible sources that reside within 50 km of a Class I area. The WRAP RMC BART screening modeling may also apply CALPUFF to downwi nd distances greater than 300 km. When providing results to the States, the downwind distance between the BART source and the Class I area will be included, and a reco mmendation from the RMC as to the utility of applying the results for Class I areas less than 50 km and grea ter than 300 km from the source. The individual States will need to make their own regulatory asse ssment of the applicability of the model results

at those distances less than 50 km and greater than 300 km.August 15, 2006

G:\WRAP RMC\BART\Protocol\Draft_Aug15_2006\WRAP_RMC_BART_Protocol_Aug15_2006.doc 3-2 

### 3.1. CALMET/CALPUFF Model Selection

The March 16, 2006 memorandum from the EPA/OAQ PS Model Clearing House is very clear on which is the regulatory vers ion of the model: “The regulat ory version of CALPUFF, along with specific regulatory options , resides on the Earth Tech website, described as the ‘EPAApproved Version’.” (Atkinson and Fox, 2006). This version was originally proposed for the BART screening analysis. However, discussions with the FLMs and others revealed that this

version of the model contained e rrors and that a newe r version should be used. Consequently, we propose to use the latest (as of April, 2006) version of the CA LPUFF modeling system (available at www.src.com):

• CALMET Version 6.211 Level 060414

• CALPUFF Version 6.112 Level 060412

3.1.1. CALMET

CALMET will be applied for separate State domains using a 4 km grid and 11 vertical layers (see Figure 3-1). A Lambert Conformal Conic (L CC) map projection will be used that is the same as used in the WRAP MM5 and CMAQ/CA Mx modeling. Terrain and land use data will be provided at 4 km grid resolution, whereas th e MM5 data will be provided at a 36 km grid

resolution.

The 36 km MM5 meteorological fields for 2001, 2002 and 2003 have been processed into the format used by CALMET. CALMET is based on the Diagnostic Wind Model (Douglas and Kessler, 1988) that was originally develope d as part of the EPA Rocky Mountain Acid Deposition Model Assessment Project (Morris et al., 1987) and later adapted for the UAM Modeling System (Morris and Myers, 1990).

CALMET/DWM uses a two-step approach to calcula te wind fields. In the first step, an initialguess wind field is adjusted for diagnostic wind effects of terrain, such as channeling, blocking and deflection and slope flows, to produce a Step 1 wind field. In Step 2, an objective analysis is performed to introduce observational data into the Step 1 wind field. For the WRAP RMC BART screening modeling, CALMET is being op erated using hourly th ree-dimensional 36 km MM5 meteorological and observed surface meteorol ogical and precipitation data. In earlier versions of this Modeling Protocol we have proposed to run CALMET using the no observations (NOOBS) mode. However, EPA/FLMs have not ed that running CALMET/CALPUFF in the

NOBS mode is less conservative that when mete orological observations are also used. The reasons why CALMET/CALPUFF run in the NOOBS model produces less conservative concentrations (i.e., lower) estimates than when observations are specified has been traced to the calculation of PGT stability Class. When surf ace meteorological observations are specified, PGT Stability Class is calculated using sky cover, solar intensity and wind speed, whereas in the NOOBS mode an alternative algor ithms is used that estimates a more unstable atmosphere and therefore enhanced dispersion and lower concentration estimat es. Using the NOOBS mode to operate CALMET/CALPUFF does not necessarily m ean it is less accurate than when surface meteorological observations are used, just that it produces lower concentration estimates and is therefore less conservative. In fact, th e IWAQM (1998) testing of the CALMET/CALPUFF modeling system against real-world observe d atmospheric tracer measurements found itAugust 15, 2006

G:\WRAP RMC\BART\Protocol\Draft_Aug15_2006\WRAP_RMC_BART_Protocol_Aug15_2006.doc 3-3 overestimated downwind measured concentrations beyond 200-300 km by a factor of 3-4 due to inadequate spread (dispersion) of the plume, suggesting that enhanced dispersion may be more

accurate.

For the BART screening analysis, initial guess wind fields based on ho urly 36-kilometer MM5 meteorological fields for 2001, 2002 and 2003 (i.e., IPROG=14) will be used. These initial guess wind fields are adjusted to account for the effects of 4 km terrain and land use data on the wind fields in Step 1 of CALMET/DWM. No te that although surface meteorological and precipitation observations are specified as input to CALMET, no observed upper-air meteorological observations will be used as they are redundant to the MM5 data and may introduce spurious artifacts in th e wind fields. In the applicat ion of the MM5, the twice daily upper-air meteorological observations are used as input with the MM5 model estimates nudged to the observations as part of the Four Dimens ional Data Assimilation (FDDA). This results in higher temporal (hourly vs. 12-hour) and spatia l (36 km vs. ~300 km) resolution upper-air meteorology in the MM5 field that is dynamically balanced than contained in the upper-air

observations. Therefore the use of the upper-air observations w ith CALMET is not needed and in fact will upset the dynamic balance of the me teorological fields pote ntially producing spurious

vertical velocities.

The EPA BART Guidelines do not state the exact number of years of mesoscale meteorological data for use in CALPUFF, but according to EP A air quality modeling guidelines (EPA, 2003c, 40 CFR 51 Appendix W) and discussed by FLAG (2000) , at least three years of meteorological data should be used. Five y ears of meteorological data is preferable, but when mesoscale meteorological data are used (i.e., MM5) three years of modeling is acceptable.

3.1.1.1. CALMET Modeling Domains

The WRAP RMC has developed seven CALM ET/CALPUFF modeling domains in the contiguous U.S. that focus on the following States and nearby Class I areas: Arizona, Montana, New Mexico, Nevada, South Dakota and Utah (Fi gure 3-1). In addition, there is an Alaska CALMET/CALPUFF modeling that is discussed in Section 4. At this time the RMC does not plan on performing CALMET/CALPUFF modeling fo r Montana. Montana has requested the 2001, 2002 and 2003 processed MM5 data and w ill conduct their own CALPUFF modeling.

All of the CALMET/CALPUFF modeling domains are based on the same Lambert Conformal Conic (LCC) map projection as used in the RPO’s MM5 and CMAQ modeling:

• X-Center = 97 ° Longitude

• Y-Center = 40 ° Latitude

• Alpha = 33 ° Latitude

• Beta = 45 ° Latitude

Using the RPO LCC map projection, each of the CALMET/CALPUFF modeling domains shown in Figure 3-1 are defined using the parameters in Table 3-1. Shown in these figures are the Class I areas, potential BART-eligible sources (when available) and the locations of the surface meteorological observation sites.August 15, 2006

G:\WRAP RMC\BART\Protocol\Draft_Aug15_2006\WRAP_RMC_BART_Protocol_Aug15_2006.doc 3-4 Table 3-1. Definition of State CALMET/CALPUFF modeling domains using the RPO LCC projections based on an origin at (-97 ° , 40 ° ) and true latitudes at 33 ° and 45 °

. SW and NE Corners (m LCP) Number of 4 km Grids
State Southwest Northeast x-direction y-direction No. Class I Receptors Arizona (-1944, -900) (-792, 0) 288 225 12,156 Montana (-1656, 360) (-360, 1296) 324 234 10,575 New Mexico (-1368, -900) (-504, -36) 216 216 4,471 Nevada CALMET (-2088, -576) (-1296, 648) 198 306 10,254 NV CALPUFF N (-2088, -200) (-1460, 500) 157 175 4900 NV CALPUFF S (-2000, -576) (-1300, 420) 175 249 8183 S. Dakota (-1080, 216) (468, 1044) 387 207 5,786 Utah (-1620, -540) (-792, 648) 207 297 11,365

These domains are quite large and many of the source-receptor distance s will exceed 300 km. Thus, when the RMC provides the modeling resu lts to the States, the distance between the potential BART-eligible source and the Class I area should be considered in their interpretation of whether a visibility impact is significant. Also, the proposed mode ling domains contain many receptors in the Class I areas (roughly 4,000-12,000). This may result in CALPUFF simulations with excessive computational requirements. Co nsequently, we will discuss the following issues with each State that would reduce the computati onal requirements of the CALPUFF simulations:

• Reductions in the size of the CALPUFF com putational domains displayed in Figure 3-1.

• Reduction in the number of receptors coveri ng the Class I areas (e.g., reduction in the density or elimination of receptors over 300 km from the sources of interest).

For the Nevada CALMET/CALPUFF mode ling, CALMET modeling for 2001, 2002 and 2003

will be conducted for the entire 198 x 306 4 km domain depicted in Figure 3-1d-1. The Nevada

BART sources are clustered either near Reno in the northern or Las Vegas in the southern parts of the State. Consequently, we will run two separate CALPUFF modeling domains, a northern

and southern domain that are shown in Fi gure 3-1d-2 and Figure 3-1d-3, respectively.August 15, 2006

G:\WRAP RMC\BART\Protocol\Draft_Aug15_2006\WRAP_RMC_BART_Protocol_Aug15_2006.doc 3-5 -2000 -1800 -1600 -1400 -1200 -1000 -800 -800 -600 -400 -200 0

Figure 3-1a. Proposed CALMET/CALPUFF modeling domain, Class I area receptors (green) and observed surface meteorological sites for Arizona.August 15, 2006

G:\WRAP RMC\BART\Protocol\Draft_Aug15_2006\WRAP_RMC_BART_Protocol_Aug15_2006.doc 3-6 -1600 -1400 -1200 -1000 -800 -600 -400 400 600 800 1000 1200

Figure 3-1b. Proposed CALMET/CALPUFF modeling domain, Class I area receptors (green) and observed surface monitoring sites (purple triangl es) for Montana (RMC currently does not have any plans for modeling Montana BART sources).August 15, 2006

G:\WRAP RMC\BART\Protocol\Draft_Aug15_2006\WRAP_RMC_BART_Protocol_Aug15_2006.doc 3-7 -1400 -1300 -1200 -1100 -1000 -900 -800 -700 -600 -500 -900 -800 -700 -600 -500 -400 -300 -200 -100 0

Figure 3-1c. Proposed CALMET/CALPUFF modeling domain, Class I area receptors (green), observed surface meteorological sites (purple triangles) and potential BART-eligible source locations (red circles) for New Mexico.August 15, 2006

G:\WRAP RMC\BART\Protocol\Draft_Aug15_2006\WRAP_RMC_BART_Protocol_Aug15_2006.doc 3-8 Figure 3-1d-1. Proposed CALMET/CALPUFF modeling domain and Class I area receptors (green) and observed surface meteorological sites (purple triangles) for Nevada.August 15, 2006

G:\WRAP RMC\BART\Protocol\Draft_Aug15_2006\WRAP_RMC_BART_Protocol_Aug15_2006.doc 3-9 Figure 3-1d-2. Proposed CALPUFF modeling domain for northern potential BART-eligible sources (red circles) near Reno and Class I area receptors (green).August 15, 2006

G:\WRAP RMC\BART\Protocol\Draft_Aug15_2006\WRAP_RMC_BART_Protocol_Aug15_2006.doc 3-10 Figure 3-1d-3. Proposed CALPUFF modeling domain for southern potential BART-eligible sources (red circles) near Las Vegas and Class I area receptors (green).August 15, 2006

G:\WRAP RMC\BART\Protocol\Draft_Aug15_2006\WRAP_RMC_BART_Protocol_Aug15_2006.doc 3-11 -1000 -800 -600 -400 -200 0 200 400 200 400 600 800 1000

Figure 3-1e. Proposed CALMET/CALPUFF modeling domain and Class I area receptors (green), observed surface meteorological sites (purple triangles) and potential BART-eligible source locations (red circles) for South Dakota.August 15, 2006

G:\WRAP RMC\BART\Protocol\Draft_Aug15_2006\WRAP_RMC_BART_Protocol_Aug15_2006.doc 3-12 -1600 -1400 -1200 -1000 -800 -600 -400 -200 0 200 400 600

Figure 3-1f. Proposed CALMET/CALPUFF modeling domain and Class I area receptors (green) and observed surface meteorological sites (purple triangles) for Utah.August 15, 2006

G:\WRAP RMC\BART\Protocol\Draft_Aug15_2006\WRAP_RMC_BART_Protocol_Aug15_2006.doc 3-13

3.1.1.2. CALMET Performance Evaluation

The CALMET meteorological fields will be spot checked for reasonableness using visualization and animation tools, but no comprehensive eval uation will be undertaken. The main inputs to CALMET are the hourly 36 km MM5 data, su rface meteorological and precipitation measurements, terrain data and land use data. The 36 km MM5 fields have been evaluated previously (McNally, 2003; Kemball-Cook et al ., 2005; Baker, 2004a,b) a nd the terrain and land use inputs will be evaluated by comparison spatial plots of the inputs against topographic and land use maps.

3.1.1.3. Terrain

Gridded terrain elevations fo r the modeling domain are derived from 3 arc-second digital elevation models (DEMs) produ ced by the United States Geologi cal Survey (USGS). The files cover 1-degree by 1-degree blocks of latitude and longitude. USGS 1:250,000 scale DEMs were

used. The elevations are in meters relative to mean sea level and have a resolution of about 90 meters. These data will be processed to generate 4 km average terrain heights that will be input

into CALMET. Additional terrain databases will be used to define terrain heights in the Canada and Mexico portions of the modeling domains as needed.

3.1.1.4. Land Use

The land use data is based on the Composite Th eme Grid format (CTG) using Level I USGS land use categories were “mapped into the 14 pr imary CALMET land use categories described in
Figure 3-2

.

Figure 3-2. Land use categories table from CALMET User's Guide.August 15, 2006

G:\WRAP RMC\BART\Protocol\Draft_Aug15_2006\WRAP_RMC_BART_Protocol_Aug15_2006.doc 3-14 3.1.1.5. CALMET ZFACE and ZIMAX Settings

Eleven vertical layers will be used with ve rtical cell face (ZFACE) heights at: 0, 20, 100, 200, 350, 500, 750, 1000, 2000, 3000, 4000, and 5000 meters.

ZIMAX was set to 4500 meters based on the CDPH E analyses of soundings for summer ozone events in the Denver area (CDPHE, 2005). The CD PHE analysis suggests mixing heights in the

Denver area are often well above the CALMET default value of 3000 meters during the summer. For example, on some summer days, ozone levels are elevated all the way to 6000 meters MSL or beyond during some meteorological regimes, in cluding some regimes associated with high ozone episodes. We suspect that, like in De nver, mixing heights in excess of the 3,000 m AGL

CALMET default maximum would occu r in the western States. Note that this is one area where we are deviating from EPA’s March 16, 2006 memorandum on CALMET/CALPUFF regulatory settings.

3.1.1.6. CALMET Options and Comparis on with Regulatory Default Settings

Table 3-2 compares the proposed CALMET options and settings with those recommended by EPA for the regulatory application of the CA LMET model (Atkinson and Fox, 2006). The RMC BART screening analysis CALMET parameters c onforms with all of EPA’s recommendations for regulatory application of the CALPUFF modeling system, with the following exceptions:

• The WRAP CALMET/CALPUFF modeling domains will be based on the same InterRPO Lambert Conformal Conic (LCC) proj ection as used in the WRAP MM5 and CMAQ modeling rather than the EPA default LCC projection.

• Proposed maximum mixing height (Z1MAX) of 4,500 m AGL vers us EPA regulatory default of 3,000 m AGL. A 3,000 m AGL maximum mixing hei ght might be appropriate in the eastern U.S., however in the west ern U.S. in the summer mixing heights may

exceed this value. In their BART Modeli ng Protocol, the CDPHE presents compelling evidence that mixing heights exceed 3,000 m AGL in Denver during the summer. We would expect other areas in the west to al so have higher mixing heights so we have adopted the 4,500 m AGL values as used by CDPHE (CDPHE, 2005);

• The EPA default assumes no MM5 data will be used (IPROG=0). In the RMC BART screening analysis MM5 data will be used as an in itial guess field (IPROG=14).

• The EPA default assumes values for IEXTRP (-4) and RMIN2 (4) that are incompatible with each other, thus we will use values that are consistent with each other (1 and 4, respectively). Because we are using hourly 36 km MM5 data to define the upper

− level winds, the extrapolation of the surface wind data aloft as recommended by EPA (IEXTRP=

− 4) is not needed and in fact would upset the dynamic balance of the aloft winds producing spurious vertical velocities.

• We are setting IAVET to 0 to turn off spatially averaging of the temperature interpolation since the MM5 temperatures with already be fairly smooth.

• We are setting the beginning and endi ng water land use categories to 51 and 55, respectively (see Figure 3

− 2), rather than EPA default (999) that assumes no water landuse categories.August 15, 2006

G:\WRAP RMC\BART\Protocol\Draft_Aug15_2006\WRAP_RMC_BART_Protocol_Aug15_2006.doc 3-15 Table 3-2. CALMET options and comparison of proposed values with EPA regulatory default settings as given by Atkinson and Fox (2006), deviations from EPA recommended defaults are indicated by bold text

.

Variable Description EPA Default Our Values GEO.DAT Name of Geophysica l data file GEO.DAT GEO.DAT

SURF.DAT Name of Surface data file SURF.DAT SURF.DAT PRECIP.DAT Name of Precipitation data file PRECIP.D AT PRECIP.DAT NUSTA Number of upper air data sites User Defined 0 UPN.DAT Names of NUSTA upper air data
files UPN.DAT NA

IBYR Beginning year User Defines User Defines IBMO Beginning month User Defines User Defines IBDY Beginning day User Defines User Defines IBHR Beginning hour User Defines User Defines

IBTZ Base time zone User Defines User Defines

IRLG Number of hours to simulate User Defines User Defines IRTYPE Output file type to create (must be 1 for CALPUFF) 1 1

LCALGRD Are w-components and temperature needed? T T

NX Number of east-west grid cells User Defines Table 3-1 NY Number of north-south grid cells User Defines Table 3-1 DGRIDKM Grid spacing User Defines Table 3-1 XORIGKM Southwest grid cell X coordinate User Defines Table 3-1 YORIGKM Southwest grid cell Y coordinate User Defines Table 3-1 XLATO Southwest grid cell latitude User Defines Table 3-1 YLONO Southwest grid cell longitude User Defines Table 3-1

IUTMZN UTM Zone User Defines NA LLCONF When using Lambert Conformal map coordinates, rotate winds from true north to map north? F F

XLAT1 Latitude of 1 st standard parallel 30 33

XLAT2 Latitude of 2 nd standard parallel 60 45 RLON0 Longitude used if LLCONF = T 90 97
RLAT0 Latitude used if LLCONF = T 40 40 NZ Number of vertical Layers User Defines 11 ZFACE Vertical cell face heights (NZ+1 values) User Defines 0,20,100,200,350,500,750,1 000,2000,3000,4000, and

5000
LSAVE Save met. Data fields in an
unformatted file? T T

IFORMO Format of unformatted file (1 for CALPUFF) 1 1

NSSTA Number of stations in SURF.DAT
file User Defines Domain dependent, see Figure 3-1 for locations

NPSTA Number of stations in
PRECIP.DAT User Defines Domain dependent, see Figure 3-1 for locations ICLOUD Is cloud data to be input as gridded fields? 0=No) 0 0

IFORMS Format of surface data (2 = formatted) 2 2

IFORMP Format of precipitation data (2= formatted) 2 2

IFORMC Format of cloud data (2= formatted) 2 2August 15, 2006

G:\WRAP RMC\BART\Protocol\Draft_Aug15_2006\WRAP_RMC_BART_Protocol_Aug15_2006.doc 3-16

Variable Description EPA Default Our Values IWFCOD Generate winds by diagnostic wind module? (1 = Yes) 1 1

IFRADJ Adjust winds using Froude number effects? (1= Yes) 1 1

IKINE Adjust winds using Kinematic effects? (1 = Yes) 0 0

IOBR Use O’Brien procedure for vertical winds? (0 = No) 0 0

ISLOPE Compute slope flows? (1 = Yes) 1 1 IEXTRP Extrapolate surface winds to upper layers? (-4 = use similarity theory and ignore layer 1 of upper air station data) -4 1

ICALM Extrapolate surface calms to upper layers? (0 = No) 0 0

BIAS Surface/upper-air weighting factors (NZ values) NZ*0 NZ*0

IPROG Using prognostic or MM-FDDA data? (0 = No) 0 14

LVARY Use varying radius to develop
surface winds? F F

RMAX1 Max surface over-land extrapolation radius (km) User Defines 50.

RMAX2 Max aloft over-land extrapolations radius (km) User Defines 100.

RMAX3 Maximum over-water extrapolation radius (km) User Defines 100.

RMIN Minimum extrapolation radius (km) 0.1 0.1

RMIN2 Distance (km) around an upper

air site where vertical extrapolation is excluded (Set to –

1 if IEXTRP = ± 4) 4 4

TERRAD Radius of influence of terrain features (km) User Defines 10.

R1 Relative weight at surface of Step
1 field and obs User Defines 100.

R2 Relative weight aloft of Step 1
field and obs User Defines 200.

DIVLIM Maximum acceptable divergence 5.E-6 5.E-6 NITER Max number of passes in divergence minimization 50 50

NSMTH Number of passes in smoothing (NZ values) 2,4*(NZ-1) 2,4*(NZ-1)

NINTR2 Max number of stations for interpolations (NA values) 99 99

CRITFN Critical Froude number 1 1 ALPHA Empirical factor triggering
kinematic effects 0.1 0.1

IDIOPT1 Compute temperatures from observations (0 = True) 0 0

ISURFT Surface station to use for surface temperature (between 1 and NSSTA) User Defines 1

IDIOPT2 Compute domain-average lapse rates? (0 = True) 0 0August 15, 2006

G:\WRAP RMC\BART\Protocol\Draft_Aug15_2006\WRAP_RMC_BART_Protocol_Aug15_2006.doc 3-17

Variable Description EPA Default Our Values IUPT Station for lapse rates (between 1 and NUSTA) User Defines 1

ZUPT Depth of domain-average lapse rate (m) 200 200

IDIOPT3 Compute inter nally initial guess winds? (0 = True) 0 0

IUPWND Upper air station for domain winds (-1 = 1/r**2 interpolation of all stations) -1 -1

ZUPWND Bottom and top of layer for 1 st guess winds (m) 1,1000 1,1000

IDIOPT4 Read surface winds from SURF.DAT? ( 0 = True) 0 0

IDIOPT5 Read aloft winds from UPn.DAT? ( 0 = True) 0 0

CONSTB Neutral mixing height B constant 1.41 1.41 CONSTE Convective mixing height E

constant 0.15 0.15

CONSTN Stable mixing height N constant 2400 2400 CONSTW Over-water mixing height W

constant 0.16 0.16

FCORIOL Absolute value of Carioles parameter 1.E-4 1.E-4

IAVEZI Spatial averaging of mixing heights? ( 1 = True) 1 1

MNMDAV Max averaging radius (number of grid cells) 1 1

HAFANG Half-angle for looking upwind (degrees) 30 30

ILEVZI Layer to use in upwind averaging (between 1 and NZ) 1 1

DPTMIN Minimum capping potential temperature lapse rate 0.001 0.001

DZZI Depth for computing capping lapse rate (m) 200 200

ZIMIN Minimum over-land mixing height (m) 50 50

ZIMAX Maximum over-land mixing height (m) 3000 4500

ZIMINW Minimum over-water mixing height (m) 50 50

ZIMAXW Maximum over-water mixing height (m) 3000 4500

IRAD Form of temperature interpolation (1 = 1/r) 1 1

TRADKM Radius of temperature interpolation (km) 500 500

NUMTS Max number of stations in temperature interpolations 5 5

IAVET Conduct spatial averaging of temperature? (1 = True) 1 0

TGDEFB Default over-water mixed layer lapse rate (K/m) -0.0098 -0.0098

TGDEFA Default over-water capping lapse rate (K/m) -0.0045 -0.0045

JWAT1 Beginning landuse type defining 999 51August 15, 2006

G:\WRAP RMC\BART\Protocol\Draft_Aug15_2006\WRAP_RMC_BART_Protocol_Aug15_2006.doc 3-18

Variable Description EPA Default Our Values

water JWAT2 Ending landuse type defining

water 999 55

NFLAGP Method for precipitation interpolation (2= 1/r**2) 2 2

SIGMAP Precip radius for interpolations (km) 100 100

CUTP Minimum cut off precip rate (mm/hr) 0.01 0.01

SSn NSSTA input records for surface

stations User Defines Figure 3-1

Usn NUSTA input records for upperair stations User Defines NA

PSn NPSTA input records for precipitations stations User Defines Figure 3-1

3.1.2. CALPUFF

The CALPUFF model will be applied followi ng EPA guidance and recommendations (EPA, 2003c; Atkinson and Fox, 2006) and other reco mmendations (IWAQM, 1998; FLAG, 2000).

3.1.2.1. Receptor Network and Class I Federal Areas

The NPS recommended receptor networks for Class I areas will be used in the analysis. The locations of these receptors for each of th e CALMET/CALPUFF modeling domains are shown in Figure 3-1. Because of the large size of the CALPUFF modeling domains, the high density of the NPS receptors in the Class I areas and the many Class I areas in the west, there may be a need to reduce the number of receptors to a more manageable number. For example, the proposed Utah CALPUFF modeling domain (Fig ure 3-1f) includes 11,365 receptors. As the CALPUFF run times depend on the number of s ources and receptors, th en specifying too many receptors results in excessive run times. Fo r PSD/NSR modeling Class I area receptors are typically limited to within 300 km of the source. The RMC will work with the WRAP Modeling Forum and affected States to determine ways to reduce the total number of receptors without sacrificing the identification of the maximum vi sibility impacts from potential BART eligible

sources at Class I areas.

3.1.2.2. CALPUFF Meteorology

The CALPUFF meteorology will be based on CALMET as described in Section 3.1.1.

3.1.2.3. CALPUFF Modeling Domain

The CALPUFF modeling domains are mostly assume d to be identical to the CALMET modeling domains and are shown in Figure 3-1. Although if run times are excessive the relevant States will be consulted about potential reductions in the size of the CALPUFF computational domain. The State of Nevada requested that two separa te CALPUFF computationa l grids be used, oneAugust 15, 2006

G:\WRAP RMC\BART\Protocol\Draft_Aug15_2006\WRAP_RMC_BART_Protocol_Aug15_2006.doc 3-19 associated with northern (Figure 3-1d-2) and one associated with southern Nevada sources (Figure 3-1d-3).

3.1.2.4. CALPUFF Parameter Summary and Comparison with Regulatory

Defaults

The CALPUFF options were selected to fo llow EPA’s recommended settings for regulatory modeling (Atkinson and Fox, 2006) as shown in Table 3-3. Differences from these

recommendations are as follows:

• The number of species modeled and emitted will depend on the emissions data provided by the States for the BART sources. If just SO 2 and NOx emissions are provided, 5 species will be modeled (SO 2 , SO4, NOx, NHNO3 and NO3) as recommended by EPA. For States that al so provide total PM10 emissions 6 species will be modeled. Potentially States could provide PM emissions split into SO4, NO3, EC, OC, PMF and PMC in which case 9 species will be modeled.

• MRESTART will be 2 for first run segment of the year and 3 for subsequent run
segments.

• The background ammonia for the CALPUFF runs will be 1 ppb that is believed to be a more representative value for the western U.S. than the 10 ppb EPA default. Note that we are still reviewing what background a mmonia value should be used when postprocessing the results to calculate ammoni a limiting where site and monthly specific values are being considered.

Table 3-3. CALPUFF options and comparison of EPA regulatory modeling default values with proposed values for the RMC BART screening analys is, bold text indicates deviations from EPA

recommendations.

Variable Description EPA Default Our Values METDAT CALMET input data filename CALMET.DAT CALMET.DAT PUFLST Filename for general output from
CALPUFF CALPUFF.LST CALPUFF.LST

CONDAT Filename for output concen tration data CONC.DAT CONC.DAT DFDAT Filename for output dry deposition fluxes DFLX.DAT DFLX.DAT WFDAT Filename for output wet deposition fluxes WFLX.DAT WFLX.DAT VISDAT Filename for output relative humidities (for visibility) VISB.DAT VISB.DAT

METRUN Do we run all periods (1) or a subset (0)? 0 0 IBYR Beginning year User Defined User Defined IBMO Beginning month User Defined User Defined IBDY Beginning day User Defined User Defined IBHR Beginning hour User Defined User Defined IRLG Length of runs (hours) User Defined User Defined NSPEC Number of sp ecies modeled (for MESOPUFF II chemistry) 5 5-9

NSE Number of species emitted 3 2-9 MRESTART Restart options (0 = no restart), allows splitting runs into smaller segments 0 2 or 3

METFM Format of input meteorology (1 = CALMET) 1 1

AVET Averaging time lateral dispersion parameters (minutes) 60 60

MGAUSS Near-field vertical distribution (1 = 1 1August 15, 2006

G:\WRAP RMC\BART\Protocol\Draft_Aug15_2006\WRAP_RMC_BART_Protocol_Aug15_2006.doc 3-20

Variable Description EPA Default Our Values Gaussian) MCTADJ Terrain adjustments to plume path (3 = Plume path) 3 3

MCTSG Do we have subgrid hills? (0 = No), allows CTDM-like treatment for subgrid scale

hills 0 0

MSLUG Near-field puff treatment (0 = No slugs) 0 0 MTRANS Model transitional plume rise? (1 = Yes) 1 1 MTIP Treat stack tip downwash? (1 = Yes) 1 1 MSHEAR Treat vertical wind shear? (0 = No) 0 0 MSPLIT Allow puffs to split? (0 = No) 0 0 MCHEM MESOPUFF-II Chemistry? (1 = Yes) 1 1 MWET Model wet deposition? (1 = Yes) 1 1 MDRY Model dry deposition? (1 = Yes) 1 1 MDISP Method for dispersion coefficients (3 = PG & MP) 3 3

MTURBVW Turbulence characterization? (Only if MDISP = 1 or 5) 3 3

MDISP2 Backup coefficients (Only if MDISP = 1 or 5) 3 3

MROUGH Adjust PG for surface roughness? (0 = No) 0 0

MPARTL Model partial plume penetration? (0 = No) 1 1 MTINV Elevated inversion strength (0 = compute from data) 0 0

MPDF Use PDF for convective dispersion? (0 = No) 0 0

MSGTIBL Use TIBL module? (0 = No) allows treatment of subgrid scale coastal areas 0 0

MREG Regulatory default checks? (1 = Yes) 1 1 CSPECn Names of species modeled (for MESOPUFF II, must be SO2, SO4, NOx, HN03, NO3) User Defined 5

Specie

Names Manner species will be modeled User Defined SO2, SO4, NOX, NO3, HNO3, PM25 (depends on

emissions data provide by States) Specie Groups Grouping of species, if any. User Defined

NX Number of east-west grids of input meteorology User Defined Table 3-1

NY Number of north-south grids of input meteorology User Defined Table 3-1

NZ Number of vertical layers of input meteorology User Defined 11

DGRIDKM Meteorology grid spacing (km) User Defined 4 ZFACE Vertical cell face heights of input meteorology User Defined Table 3-2

XORIGKM Southwest corner (east-west) of input meteorology User Defined Table 3-1

YORIGIM Southwest corner (north-south) of input meteorology User Defined Table 3-1

IUTMZN UTM zone User Defined NA XLAT Latitude of center of meteorology domain User Defined Table 3-1 XLONG Longitude of center of meteorology User Defined Table 3-1August 15, 2006

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Variable Description EPA Default Our Values

domain XBTZ Base time zone of input meteorology User Defined MST IBCOMP Southwest of Xindex of computational

domain User Defined Table 3-1

JBCOMP Southwest of Y-index of computational

domain User Defined Table 3-1

IECOMP Northeast of Xindex of computational

domain User Defined Table 3-1

JECOMP Northeast of Y- index of computational

domain User Defined Table 3-1

LSAMP Use gridded receptors (T -= Yes) F F

IBSAMP Southwest of Xindex of re ceptor grid User Defined NA

JBSAMP Southwest of Y-index of re ceptor grid User Defined NA

IESAMP Northeast of Xindex of re ceptor grid User Defined NA

JESAMP Northeast of Y-index of re ceptor grid User Defined NA MESHDN Gridded receptor spacing =
DGRIDKM/MESHDN 1 NA

ICON Output concentrations? (1 = Yes) 1 1 IDRY Output dry deposition flux? (1 = Yes) 1 1 IWET Output wet deposition flux? (1 = Yes) 1 1 IVIS Output RH for visibility calculations (1 = Yes) 1 1

LCOMPRS Use compression option in output? (T = Yes) T T

ICPRT Print concentrations? (0 = No) 0 0 IDPRT Print dry deposition fluxes (0 = No) 0 0 IWPRT Print wet deposition fluxes (0 = No) 0 0 ICFRQ Concentration print interval (1 = hourly) 1 1 IDFRQ Dry deposition flux print interval (1 = hourly) 1 1

IWFRQ Wet deposition flux print interval (1 = hourly) 1 1

IPRTU Print output units (1 = g/m**3; g/m**2/s) 1 1 IMESG Status messages to screen? (1 = Yes) 1 1 Output Species Where to output various species User Defined Default

LDEBUG Turn on debug tracking? (F = No) F F Dry Gas Dep Chemical parameters of gaseous deposition species User Defined Default

Dry Part. Dep Chemical pa rameters of particulate deposition species User Defined Default

RCUTR Reference cuticle resistance (s/cm) 30. 30. RGR Reference ground resistance (s/cm) 10. 10. REACTR Reference reactivity 8 8 NINT Number of particle-size intervals 9 9 IVEG Vegetative state (1 = active and unstressed) 1 1

Wet Dep Wet deposition parameters User Defined TBD MOZ Ozone background? (1 = read from ozone.dat) 1 1

BCKO3 Ozone default (ppb) (Use only for missing data) 80 80

BCKNH3 Ammonia background (ppb) 10 1 RNITE1 Nighttime SO2 loss rate (%/hr) 0.2 0.2 RNITE2 Nighttime NOx loss rate (%/hr) 2 2 RNITE3 Nighttime HNO3 loss rate (%/hr) 2 2August 15, 2006

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Variable Description EPA Default Our Values SYTDEP Horizontal size (m) to switch to time dependence 550. 550.

MHFTSZ Use Heffter for vert ical dispersion? (0 = No) 0 0

JSUP PG Stability class above mixed layer 5 5 CONK1 Stable dispersion const ant (Eq. 2.7-3) 0.01 0.01 CONK2 Neutral dispersion cons tant (Eq. 2.7-4) 0.1 0.1 TBD Transition for downwash algorithms (0.5 = ISC) 0.5 0.5

IURB1 Beginning urban landuse type 10 10 IURB2 Ending urban landuse type 19 19

3.1.2.5. Chemical Mechanism

The MESOPUFF II pseudo-first-order chemical reaction mechanism (MCHEM=1) will be used

for the conversion of SO 2 to sulfate (SO4) and NOx to nitrate (NO3) as recommended by EPA (Atkinson and Fox, 2006).

3.1.2.6. Ammonia Assumptions

Ammonia is not simulated by CALPUFF, but rath er a background value is specified. Ammonia is important because the level of particulate nitrate (NO3) can depend on the amount of ammonia present. The partitioning of total nitrate between gaseous HNO3 and particulate NO3 depends on the amount of ammonia present and other parameters (e.g., SO4, temperature and RH). In the CALPUFF simulation, one value for background amm onia is assumed across the region and each puff uses the full background value in its equi librium calculation even though puffs may be overlapping thereby “double count ing” the background ammonia value. However, in postprocessing the results, you may specific hourly values at receptor s and recalculate the HNO3/NO3 equilibrium partitioning on the total concentration due to al l overlapping puffs at a
receptor.

The IWAQM Phase II report contains the follo wing recommendations for background ammonia “typical (within a factor of 2) background valu es of ammonia are: 10 ppb for grasslands, 0.5 ppb for forest, and 1 ppb for arid lands at 20 C” (IWAQM, 1998). The CDPHE performed analysis

for Colorado and concluded that for sources loca ted in northeast Colorado and along the South Platte River, a domain-wide ammonia background value of 44 ppb is used. For sources located in northwest Colorado, a background ammonia concentration of 1.0 ppb is used. For sources

located in southeastern Colora do and for sources located along the Arkansas River, a background value of 10 ppb is used.

In a CALPUFF application, the background ammonia concentration is temporally and spatially uniform. It is likely that some portions of th e modeling domain are ammonia poor and some are ammonia rich. Thus, setting a si ngle domain-wide bac kground is problematic. There is no one value that is likely valid across the modeling domains in Figure 3- 1 or even across the different seasons at one particulate location. Alt hough the domain-wide background ammonia value specified in the CALPUFF run is important because it determines how much of the total nitrate is gaseous (HNO3) versus particles (NO3) and theref ore affects the dry and wet deposition rates,August 15, 2006

G:\WRAP RMC\BART\Protocol\Draft_Aug15_2006\WRAP_RMC_BART_Protocol_Aug15_2006.doc 3-23 the specification of the backgr ound ammonia in the post-processi ng step to partition the total nitrate from overlapping puffs at the Class I areas into HNO3 and NO3 is even more important. Thus, based on the fact that wester n Class I areas tend to be either more arid or forest land than grassland we proposed to initially use a 1 ppb background ammonia value for the CALPUFF runs. We will then revisit the background ammo nia values for the Class I areas for the postprocessing step and provide the CALPUFF output to the States so they can investigate alternative background ammonia values if desired.

3.1.2.7. Ozone Assumptions

Hourly ozone concentrations from the EPA AIRS and CASTNet networks will be processed and provided as input to the CALPUFF modeling for the three years of modeling.

3.1.3. CALPOST Settings a nd Visibility Post-Processing

The CALPUFF results will be post-processed using the CALPOST and POSTUTIL or their functional equivalents. The CDPHE had to modify these programs to output the correct values needed for BART analysis. The WRAP RMC may also need to make modifications or perform the post-processing using different tools to obtain the metrics needed for a BART analysis.

To calculate background light extinction, MVISBK should be set to 6. That is, monthly RH adjustment factors (EPA, 2003b) are applied dire ctly to the background and modeled sulfate and nitrate concentrations, as recommended by the EPA BART Guidelines (EPA, 2005). The RHMAX parameter, which is the maximum relative humidity factor used in the particle growth equation for visibility processing, is not used when method 6 is selected. Similarly, the relative humidity adjustment factor (f(RH)) curves in CALPOST (e.g., IWAQM growth curve and the 1996 IMPROVE curve) are not used when MVISBK is equal to 6. The monthly f(RH) values recommended by EPA would be used (EPA, 2003a,b).

EPA lists three types of Natural Conditions (nat ural background) in th eir guidance document, Annual Average, Best 20% (B20%) Days and Worst 20% (W20%) Days (EPA, 2003a). The

EPA BART Guidance recommends th at the Natural Conditions co rresponding to the Best 20% Days be used (EPA, 2005). However, UARG challenged this assumption and EPA has determined that Annual Average Natural Conditi ons can be used for BART determinations (Paise, 2006a,b). In this analysis, the visibility impacts will be calculated using al l three sets of Natural Conditions (Annual Average, B20% and W20%) and provided to the States.August 15, 2006

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# 4. ALASKA CALPUFF BART Modeling

The Alaska CALPUFF modeling will follow the ge neral procedures outl ined for the other WRAP States described in Section 3, only it wi ll be based on Alaska MM5 modeling conducted by WRAP for the 2002 calendar year (Kemball-C ook et al., 2005). The WRAP RMC performed MM5 meteorological modeling of Alaska for 2002 on a 45/15 km nested grid. Numerous sensitivity tests were conducted to determine th e best physics options and other parameters (e.g., time of year when sea ice forms and melts) to optimized model performance. The Alaska MM5 modeling is described in the report “Ala ska MM5 Modeling for the 2002 Annual Period to Support Visibility Modeling” by Kemball-Cook and co-workers (2005) and can be found at:

http://pah.cert.ucr.edu/aqm/308/docs/ alaska/Alaska_MM5_DraftReport_Sept05.pdf

Figure 4-1 displays the locations of the potential BART-eligible s ources in Alaska along with the Denali (central Alaska), Tuxedni (Cook Inlet), Si menof (Aleutian Islands) and Bearing Sea (far west) Class I areas. Both the Simenof (> 700 km) and Bearing Sea (> 1000 km) lie far away from the potential BART-eligible sources in Alaska, so will not be considered in the analysis.

-1000 -800 -600 -400 -200 0 200 400 -400 -200 0 200 400 600 800

Figure 4-1. Locations of potential BART-eligible sources (red dots) and Class I areas (green regions) in Alaska.August 15, 2006

G:\WRAP RMC\BART\Protocol\Draft_Aug15_2006\WRAP_RMC_BART_Protocol_Aug15_2006.doc 4-2 The early versions of the WRAP draft mode ling protocol for BART modeling in Alaska proposed to model most of Alaska using a 5 km grid and no observations (NOOBS mode). However, when the Alaska Department of Envi ronmental Protection (ADEQ) provided their list of potential BART-eligible sources it was noted that most of themare located in the AnchorageValdez area in southern Alaska, w ith one located just northeast of Denali Na tional Park (Figure 4-1). Concerns were raised that operating CALMET using 5 km resolution with the 15 km MM5

data in the NOOBS mode would not adequately capture the airf lows around the Cook Inlet that would be important in simulating the potential visibility impacts at Tuxedni Wildlife Refuge

from BART sources located in southern Al aska. Consequently, the ADEQ sponsored the acquisition and reformatting of surface meteorologi cal observations for input into CALMET and the year 2002 and the Alaska BART modeling do main was redefined with a 2 km resolution grid.



### 4.1. CALMET Modeling

Although the MM5 modeling was performed on a polar stereographic domain at 45/15 km resolution, since the CALMET/CALPUFF domain did not go as far north we were able to use a Lambert Conformal Conic (LCC) projection at 2 km resolution using the domain definition provided in Table 4-1.

Table 4-1. Definition of the CALMET/CALPUFF Alaska BART modeling domain using a Lambert Conformal Conic (LCC) map projection.

Longitude Origin -151 degrees Latitude Origin 59 degrees

1 st Standard Parallel 30 degrees

2 nd Standard Parallel 60 degrees X-Origin Offset -200 km Y-Origin Offset 0 km

Horizontal Grid Resolution 2 km

Number of Grids 275 x 325

Domain Extent 550 km x 650 km

CALMET will be run using the 15 km resoluti on 2002 MM5 data (Kemball-Cook et al., 2005), surface meteorological observations from five s ites and terrain and landuse data. The locations of the five surface meteorological sites are shown in Table 4-2. Precipitation data will be based on the MM5 15 km resolution output. Similar CALMET options will be used for the Alaska CALMET modeling as discussed in Chapter 3 (i.e., Table 3-2), only using the MM5 precipitation instead of observed precipitation.

Table 4-2. Locations of the 5 surface meteorol ogical sites used in the Alaska BART CALMET/CALPUFF modeling. Site ID LCC-X (km) LCC-Y(km)

EDF 26401 64.614 250.825

PANC 26451 53.916 245.081

VWS 26442 251.006 244.575

ENA 26523 -12.782 175.868
HOM 25507 -27.103 72.100August 15, 2006

G:\WRAP RMC\BART\Protocol\Draft_Aug15_2006\WRAP_RMC_BART_Protocol_Aug15_2006.doc 4-3 -200 -100 0 100 200 300 0 100 200 300 400 500 600

Figure 4-2. Alaska BART CALMET/CALPUFF modeling domain showing the potential BART-eligible sources (red dots) and Denali and Tuxedni Class I area receptors.



### 4.2 . CALPUFF Modeling

The Alaska BART CALPUFF model will be operated with similar re gulatory default settings as discussed in Section 3 (Table 3-3). One major difference is the background ammonia value. The IWAQM (1998) recommendations for background a mmonia are representative for the lower 48 states and may not be appropriate for Alaska wher e lower values are expected to occur. Also, the regulatory default background ozone value wh en no measurements are available (80 ppb) is also too high for Alaska. Thus, initial back ground ammonia and ozone values of 0.1 ppb and 40 ppb will be used for the Alaska BART CALP UFF modeling. The specifications of the background ammonia and default background ozone values are undergoing review.August 15, 2006

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# 5. Results

For each modeling day, the CALPUFF modeling resu lts would be processed to extract maximum 24-hour visibility impact at a ny receptor in a Class I area due to a potential BART-eligible source. These maximum 24-hour visibility impact s would be expressed as changes in deciview using three levels of Natural Conditions (Annual Average and Best 20% and Worst 20% Days). For each potential BART-eligible source, Cl ass I area and modeling day (2001, 2002 and 2003), the maximum 24-hour visibility impact would be provided to the States who would make the subject to BART determination. Spread sheets of daily change in deciview impacts would be provided to each State for each of the State’s potential BART-eligible source. The maximum

and 98 th percentile change in deciview would also be provided in summary form to the States.

The CALMET and CALPUFF modeling databases will al so be provided to the States if desired.

Information on the status of the WRAP BA RT CALMET/CALPUFF modeling will be posted on

the WRAP RMC Website:

http://pah.cert.ucr.edu/aqm/308/bart.shtml

The CALMET MM5 inputs are quite large (several hundred Gb of data) and will be provided on

IDE disks that will be distri buted to the States as desire d for copy. The rest of the CALMET/CALPUFF modeling inputs will be provi ded on the WRAP RMC Website at the link provided above. CALMET output will not be distri buted; rather all CALMET inputs and scripts

will be made available so that the CALMET out put can be recreated. CALPOST (or similar post-processing program) output will be avai lable on the WRAP RMC Website and depending on their size CALPUFF modeling ou tput will be either ava ilable through the Website, ftp

transfer or IDE disk transfer.

Note that the WRAP RMC will conduct the BA RT screening CALPUFF/ CALMET modeling on Linux computing platforms. If states wish to use a windows platform then they will have to

make the conversion.August 15, 2006

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# 6. References

Atkinson, D. and T. Fox. 2006. Dispersion Coefficients for Regul atory Air Quality Modeling in

CLAPUFF . Memorandum from U.S. EPA/OAQ PS to Kay T. Prince, EPA Region 4.

March 16.

Baker, K. 2004a. Summer MM5 Performance. Midwest Regional Planning Organization. ( http://www.ladco.org/tech/phot o/present/MPE_MM5_summer.pdf ). November.

Baker, K. 2004b. Monthly Rainfall Evaluati on. Midwest regional Planning Organization. ( http://www.ladco.org/tech/ photo/present/rainfall_eval.pdf ). November.

CDPHE. 2005. CALMET/CALPU FF BART Protocol for Cla ss I federal Area Individual Source Attribution Visibility Impairment Modeling Analysis. Colorado Department of Public Health and Environment, Air Pollu tion Control Division, Denver, Colorado.

October 24.

Douglas, S. and R. Kessler. 1988. User's Guide to the Diagnostic Wind Model (Version 1.0). Systems Applications, Inc., San Rafael, CA.

Escoffier-Czaja, Christelle and J. Scire. 2002. “The Effects of Ammonia Limitation on Nitrate Aerosol Formation and Visibility Impacts in Class I Areas.” Earth Tech, Inc., Extended

abstract. 12th Joint Conference on the Applications of Air Pollu tion Meteorology with the Air and Waste Management Association , Norfolk, VA, Amer. Meteor. Soc, J5.13.

EPA. 2003a. “Guidance for Estimating Natural Vi sibility Conditions under the Regional Haze Rule.” EPA-454/B-03-005. September 2003.

EPA. 2003b. “Guidance for Tracking Progress unde r the Regional Haze Rule.” U.S. EPA, EPA454/B-03-004. September 2003.

EPA. 2003c. “Revisions to the Guideline on Ai r Quality Models: Adoption of a Preferred Long Range Transport Model and Other Resources ”; Final Rule. Fed. Reg./Vol. 68, No. 72/Tuesday April 15, 2003/Rules and Regulations. 40 CFR51.

EPA. 2005. “Regional Haze Regulations a nd Guidelines for Best Available Technology (BART) Determinations”. Fed. Reg./Vol. 70, No. 128/Wed. July 6, 2005, Rules and Regulations, pp. 39104-39172. 40 CFR Part 51, FRL-7925-9, RIN AJ31.

FLAG. 2000. “Federal Land Manager’s Air Qu ality Related Values Workgroup (FLAG): Phase I Report,” U.S. Forest Service, National Park Service, U.S. Fish and Wildlife Service,

December 2000.

IWAQM. 1998. “Interagency Workgroup on Air Quality Modeling (IWAQM) Phase 2 Summary Report and Recommendations for M odeling Long Range Transport Impacts.” EPA-454/R-98-019, December 1998.August 15, 2006

G:\WRAP RMC\BART\Protocol\Draft_Aug15_2006\WRAP_RMC_BART_Protocol_Aug15_2006.doc 6-2 Kemball-Cook, S., Y. Jia, C. Emery, R. Morris, Z. Wang and G. Tonnesen. 2004. 2002 Annual MM5 Simulation to Support WRAP CMAQ Vi sibility Modeling for the Section 308 SIP/TIP – MM5 Sensitivity Simulations to Id entify a More Optimal MM5 Configuration for Simulating Meteorology in the Western United States. We stern Regional Air Partnership, Regional Modeling Center. December 10. (http://pah.cert.ucr.e du/aqm/308/reports/mm5/MM5 SensitivityRevRep_Dec_10_2004.pd f)

Kemball-Cook, S., Y. Jia, C. Emery and R. Morris. 2005. Alaska MM5 Modeling for the 2002 Annual Period to Support Visibility Mode ling. Western Regional Air Partnership, Regional Modeling Center. September. (http://pah.cert.ucr.edu/ aqm/308/docs/alaska/Alaska_ MM5_DraftReport_Sept05.pdf)

Malm, W., M. Pitchford, M. Scruggs, J. Sisler , R. Ames, S. Copeland, K. Gebhart and D. Day. 2000. Spatial and Seasonal Patterns and Temporal Variability of Haze and its Constituents in the United States. Cooperative Institute for Research in the Atmosphere, Colorado State University, Fort Collins, CO. May.

McNally, D.E. 2003. Annual Application of MM5 for Calendar Year 2001. Prepared for U.S. EPA, Office of Air Quality and Planning St andards. Prepared by Alpine Geophysics, Arvada, CO.

Morris, R.E., R.C. Kessler, S.G. Douglas and K.R. Styles. 1987. The Rocky Mountain Acid Deposition Model Assessment Project – Ev aluation of Mesoscale Acid Deposition Models for use in Complex Terrain. Prep ared for U.S. Environmental Protection Agency, Research Triangle Park, NC.

Morris, R.E. and T.C. Myers. 1990. User’s Guid e for the Urban Airshed Model. Prepared for U.S. Environmental Protection Agency (EPA-450/4-90-007a).

NDDH. 2005. Protocol for BART -Related Visibility Impairment Modeling Analysis in North Dakota (Draft). North Dakota Department of Health, Division of Air Quality, Bismarck,

North Dakota. October 26.

Paise, J.W. 2006a. Regional Haze Regulations and Guidelines for Best Available Retrofit Technology (BART) Determinations. Memorandum to Kay Prince, Branch Chief EPA Region 4. Attachment A to April 20, 2006 DC Circuit Court document UARG vs. EPA,

No. 06-1056.

Paise, J.W. 2006b. Letter to Mel S. Schulze, Esq., Hunton and Williams representing the Utility Air Regulatory Group (UARG). Attachment B to April 20, 2006 DC Circuit Court document UARG vs. EPA, No. 06-1056.

Scire, J.S., D.G. Strimaitis, R.J. Yamartino. 2000a. “A User's Guide for the CALPUFF Dispersion Model.” Earth T ech, Concord, MA, January 2000.

Scire, J.S., F. Robe, F.E. Fernau, R.J. Yamartino. 2000b. “A User's Guide for the CALMET Meteorological Model.” Earth Tech, Concord, MA, January 2000.