BART Air Modeling Protocol 

Individual Source Visibility Assessments 

for BART Control Analyses 

September, 2006 

State of Wyoming 

Department of Environmental Quality 

Air Quality Division 

Cheyenne, WY 82002 
Table of Contents 

1.0 INTRODUCTION .................................................................................................. 3 

2.0 OVERVIEW ........................................................................................................... 4 

3.0 EMISSIONS DATA FOR MODELING ................................................................ 7 

3.1 Baseline Modeling .............................................................................................. 7 

3.2 Post-Control Modeling........................................................................................ 8 

4.0 METEOROLOGICAL DATA................................................................................ 9 

5.0 CALPUFF MODEL APPLICATION................................................................... 12 

6.0 POST PROCESSING ........................................................................................... 15 

7.0 REPORTING........................................................................................................ 19 

2
1.0 INTRODUCTION 

The U.S. EPA has issued final amendments to the Regional Haze Regulations, 

along with Guidelines for Best Available Retrofit Technology (BART) Determinations.(1)

The guidelines address the methodology for determining which facilities must apply 

BART (sources subject-to-BART) and the evaluation of control options. 

The State of Wyoming used air quality modeling in accordance with the EPA 

Guidelines to determine the Wyoming sources which are subject-to-BART. This 

Protocol defines the specific methodology to be used by those sources for determining 

the improvement in visibility to be achieved by BART controls. 

The methodology presented in this Protocol is consistent with EPA guidance and 

the Air Quality Division (AQD) determination of subject-to-BART sources. It is 

intended that all Wyoming sources that must conduct BART analyses will use this

Protocol for their evaluation of control technology visibility improvement. Any

deviations from the procedures described herein must be approved by the Division prior 

to implementation. 

 (1)

 40 CFR Part 51: Regional Haze Regulations and Guidelines for Best Available Retrofit Technology 

(BART) Determinations; Final Rule. 70 Federal Register, 39103-39172, July 6, 2005. 

3
2.0 OVERVIEW 

Wyoming AQD determined that eight facilities (sources) in the state are subjectto-BART. The sources are listed in Table 1. Division modeling indicated that each of

these sources causes or contributes to visibility impairment in one or more Class I areas.

Each source must conduct a BART analysis to define Best Available Retrofit Technology 

(BART) applicable to that source, and quantify the improvement in Class I visibility 

associated with BART controls. This Protocol sets out the procedures for quantifying 

visibility improvement. Other aspects of the full BART analysis are not addressed here. 

There are many Class I areas within and surrounding Wyoming (See Figure 1). 

On the basis of distance from subject-to-BART sources, topography, meteorology, and

prior modeling, the AQD has determined that only five Class I areas need be addressed in

BART individual source analyses. These are Badlands and Wind Cave National Parks in 

South Dakota, Mt. Zirkel Wilderness Area in Colorado, and Bridger and Fitzpatrick 

Wilderness Areas in Wyoming. Sources in eastern Wyoming have been shown to have 

greatest visibility impacts at the two South Dakota Class I areas, and western Wyoming 

sources have maximum impacts at Bridger and Fitzpatrick Wilderness Areas, and Mt.

Zirkel. Visibility improvement at these highest impact areas will provide the best 

measure of the effectiveness of BART controls. 

Each facility should carry out modeling with the CALPUFF modeling system for 

the Class I areas specified in Table 2. The AQD will provide meteorological input for 

CALMET for the years 2001, 2002, and 2003. The model domain covered by the AQD 

meteorological data is centered in southwest Wyoming, and extends roughly from Twin

Falls, ID in the west to the Missouri River in the east, and from Denver in the south to 

Helena, MT in the north. The domain is shown, along with Class I areas, in Figure 1. 

Sources may wish to utilize a smaller domain for CALPUFF modeling. Smaller 

domains are acceptable if they provide adequate additional area beyond the specific 

source and Class I areas being addressed. Figure 1 includes a “southwest Wyoming” 

domain which represents the minimum acceptable area for sources impacting the Bridger 

and Fitzpatrick Wilderness Areas, and the Mt. Zirkel Wilderness Area, and a “northeast 

Wyoming” domain as a minimum area for Badlands and Wind Cave National Parks 

modeling. 

The CALPUFF model should be used with each of the three years of

meteorological data to calculate visibility impacts for a baseline (existing emissions) 

case, and for cases reflecting BART controls. The control scenarios are to include 

individual scenarios for proposed BART controls for each pollutant (SO2, NOx, and

particulate matter), and a combined scenario representing application of all proposed 

BART controls. If desired, additional modeling may be performed for controls that are 

not selected as BART. This might be done, for example, to provide data useful in 

identifying the control technologies that represent BART. However, visibility modeling 

is required only for the proposed BART controls.

4
Table 1. Wyoming Sources Subject-to-BART 

Basin Electric Laramie River Power Plant Boilers #1,2,3 

FMC Corporation Granger Soda Ash Plant Boilers #1,2 

FMC Corporation Green River Sodium Plant Three boilers 

General Chemical Co. Green River Soda Ash Two boilers 

PacifiCorp Dave Johnson Power Plant Boilers #3,4 

PacifiCorp Jim Bridger Power Plant Boilers #1-4

PacifiCorp Naughton Power Plant Boilers #1,2,3 

PacifiCorp Wyodak Power Plant Boiler 

Results of visibility modeling will be presented as a comparison between baseline 

impacts and those calculated for the BART control scenarios. Quantitative measures of 

impact will be the 98th percentile deciview change (∆dv) relative to the 20% best days 

natural background, and the number of days with deciview change exceeding 0.5 (EPA 

Regional Haze Regulations and Guidelines for Best Available Retrofit Technology 

(BART) Determinations, 70 FR 39103). Results should be presented for each year. 

 

5
Table 2. Source-Specific Class I Areas to be Addressed 

Source Class I Areas to be Evaluated 

Basin Electric 

Laramie River 

Wind Cave NP, Badlands NP 

FMC Corporation 

Granger Soda Ash 

Bridger WA, Fitzpatrick WA 

FMC Corporation 

Sodium Products 

Bridger WA, Fitzpatrick WA 

General Chemical 

Green River Soda Ash 

Bridger WA, Fitzpatrick WA 

Pacificorp 

Dave Johnston 

Wind Cave NP, Badlands NP 

Pacificorp 

Jim Bridger 

Bridger WA, Fitzpatrick WA, 

Mt. Zirkel WA 

Pacificorp 

Naughton Plant 

Bridger WA, Fitzpatrick WA 

Pacificorp 

Wyodak 

Wind Cave NP, Badlands NP 

6
3.0 EMISSIONS DATA FOR MODELING 

CALPUFF model input requires source (stack) – specific emission rates for each

pollutant, and stack parameters (height, diameter, exit gas temperature, and exit gas 

velocity). Per EPA BART guidance, these parameters must be representative of 

maximum actual 24-hour average emitting conditions for baseline (existing) operation, 

and maximum proposed 24-hour average emissions for future (BART) operations. 

3.1 Baseline Modeling 

Sources are required to utilize representative baseline emission conditions if data

are available; baseline emissions must be documented. Possible sources of emission data 

are stack tests, CEM data, fuel consumption data, etc. Remember that emissions should 

represent maximum 24-hour rates. EPA BART guidance states that you should “Use the 

24-hour average actual emission rate from the highest emitting day of the meteorological 

period modeled (for the pre-control scenario).” Thus, baseline conditions should 

reference data from 2001 through 2003 (or 2004). 

As a minimum, modeled emissions must include: 

 SO2 sulfur dioxide 

 NOx oxides of nitrogen 

 PM2.5 particles with diameter less than 2.5μm

PM10-2.5 particles with diameters greater than 2.5μm but less 

than or equal to 10 μm

If the fraction of PM10 in the PM2.5 (fine) and PM10-2.5 (coarse) categories cannot 

be determined all particulate matter should be assumed to be PM2.5. 

In addition, direct emissions of sulfate (SO4) should be included where possible.

Sulfate can be emitted as sulfuric acid (H2SO4), sulfur trioxide (SO3), or as sulfate 

compounds; emissions should be quantified as the equivalent mass of SO4. 

When test or engineering data are not available to specify SO4 emissions or the

relative fractions of fine and coarse particles, use can be made of speciation profiles 

available from Federal Land Managers at the website 

http://ww2.nature.nps.gov/air/permits/ect/index.cfm. Profiles are available for a number 

of source type and control technology combinations. The FLM speciation factors are 

acceptable if data are available for the appropriate source type.

Emissions of VOC (volatile organic compounds), condensable organics measured 

in stack tests, and elemental carbon components of PM10 do not need to be included for

BART modeling. The only other pollutant noted in EPA BART guidance is ammonia 

(NH3). Though ammonia is not believed to be a significant contributor to visibility

7
impairment in most cases in Wyoming, it could be important for sources with significant 

ammonia emissions – for example from some NOx control systems. Sources that are 

expected to emit ammonia (in pre-or post-control configurations) should include 

ammonia emissions in their model input. 

If quantitative baseline emissions data are unavailable and sources believe that the 

maximum 24-hour emission rates estimated by the Division (presented in the Subject-toBART final report) are representative of baseline conditions for their facility, they may

be used for baseline modeling. However, emissions of sulfate and ammonia (if

applicable) should be included based on the best available test information or speciation 

factors from current literature. 

3.2 Post-Control Modeling 

All pollutants described above should be included for each post-control scenario. 

Post-control emissions (maximum 24-hour average) will generally be the baseline 

emissions multiplied by a control factor appropriate to the BART control. However, 

some proposed controls may simply increase the efficiency of existing controls; others 

may result in an increase in emissions of one pollutant while controlling another. These 

factors must all be considered in defining emission rates for post-control modeling. Any

changes in stack parameters resulting from control application must also be included.

The required visibility assessment will include the effect of each proposed BART 

control. For example, if a source proposes to add a scrubber for SO2 control, low NOx

burners for NOx control, and a baghouse for particulate control, four sets of visibility 

results should be developed: 

• Use of SO2 control alone 

• Use of NOx control alone 

• Use of particulate control alone 

• Use of proposed combination of all three controls 

All pollutants should be modeled in each CALPUFF model run, but the modeled 

emissions should reflect only the specific controls or combination of controls addressed 

in that run. 

Additional modeling could be necessary in situations where a facility is

comprised of more than one subject-to-BART source, and different BART controls are 

applicable to different sources. Excessive modeling to address multiple control 

combinations is not necessary; however, visibility modeling should quantify the effect of 

BART controls on all affected sources for each pollutant, and of all facility BART 

controls combined. 

8
4.0 METEOROLOGICAL DATA 

Wyoming AQD will provide MM5 meteorological data fields for years 2001, 

2002, and 2003 that can be utilized as input to CALMET. The MM5 output will have 12 

kilometer resolution and cover the full domain shown in Figure 1. 

Mesoscale meteorological data (MM5) were developed and evaluated as part of 

the AQD’s southwest Wyoming NO2 increment analysis. Three years of MM5 data at 36

km resolution were used to initialize 12 km MM5 simulations. The 12km MM5

modeling used identical physics options to the original 36 km runs. CALMM5 was then 

used as a preprocessor to produce CALMET – ready MM5 data input files. Quality 

assurance was performed by comparing the original MM5 output on the 36km national 

RPO grid to the 12 km MM5 output and observations. 

The CALMET model (version 5.53a, level 040716) should be used to prepare 

meteorological input for CALPUFF. The user may select a domain smaller than the 

MM5 domain for CALMET and CALPUFF modeling if desired. Figure 1 shows 

minimum domain areas for modeling of western and eastern Wyoming BART sources.

Four kilometer resolution should be specified for CALMET output. 

CALMET processing should use the AQD MM5 data, and appropriate surface,

upper air, and precipitation data. Figure 2 shows the locations of surface and upper air 

stations within the MM5 model domain. The MM5 data are used as the initial guess 

wind field; this wind field is then adjusted by CALMET for terrain and land use to 

generate a step 1 wind field, and refined using surface and upper air data to create the 

final step 2 wind field. 

Surface, upper air, and precipitation data can be obtained from the National 

Climatic Data Center. Land use and terrain data are available from the U.S. Geological 

Survey. Data can be formatted for use in CALMET with standard conversion and

processing programs available with the CALMET/CALPUFF software. 

Table 3 provides a listing of applicable CALMET input variables for BART 

meteorological processing. The table includes inputs that are specific to Wyoming

BART modeling. Inputs not shown in Table 3 are not relevant to the present application, 

are dependent on the specific model domain of the user, use model default values, or are 

obvious from the context. 

9
Table 3. CALMET Control File Inputs 

Variable Description Value

Input Group 1 

IBYR Year 2001

2002

2003

IBTZ Base time zone 7 

IRTYPE Run type 1

LCALGRD Compute data fields for CALGRID T 

Input Group 2 

PMAP Map projection LCC

DGRIDKM Grid spacing (km) 4 

NZ Number of layers 10 

ZFACE Cell face heights (m) 0 

20

40

100

140

320

580

1020

1480

2220

3500

Input Group 4 

NOOBS No observation Mode 0 

Input Group 5 

IWFCOD Model selection variable 1 

IFRADJ Froude number adjustment 1 

IKINE Kinematic effects 0

IOBR Use O’Brien procedure 0 

ISLOPE Slope flow effects 1 

IEXTRP Extrapolate surface wind observations -4 

ICALM Extrapolate calm surface winds 0 

BIAS Biases for weights of surface and upper 

air stations 

All 0 

RMIN2 Minimum distance for extrapolation -1 

IPROG Use gridded prognostic model output 14 

ISTEPPG Time Step (hours) 1 

LVARY Use varying radius of influence F 

10
Table 3. CALMET Control File Inputs (continued) 

Variable Description Value

RMAX 1 Maximum radius of influence (km) 30 

RMAX 2 Maximum radius of influence (km) 50 

RMIN Minimum radius of influence (km) 0.1 

TERRAD Radius of influence for terrain (km) 15 

R1 Relative weighting of first guess wind field and 

observations (km)

5 

R2 Relative weighting aloft (km) 25 

IDIOPT 1 Surface temperature 0 

IDIOPT 2 Upper air lapse rate 0 

ZUPT Lapse rate depth (m) 200 

IDIOPT 3 Average wind components 0 

IUPWND Upper air station -1 

ZUPWND (1) 

ZUPWND (2) 

Bottom and top of layer for domain 

scale winds (m) 

1, 1000 

1, 1000 

IDIOPT4 Surface wind components 0 

IDIOPT5 Upper air wind components 0 

Input Group 6 

IAVEZI Spatial averaging 1

MNMDAV Max search radius 1

HAFANG Half angle for averaging (deg) 30 

ILEVZI Layer of winds in averaging 1 

ZIMAX Maximum overland mixing height (m) 3500 

ITPROG 3D temperature source 1 

IRAD Interpolation type 1

TRADKM Radius of influence – temperature (km) 500 

NUMTS Maximum number of Stations 5 

IAVET Spatial averaging of temperatures 1 

NFLAGP Precipitation interpolation 2

11
5.0 CALPUFF MODEL APPLICATION 

The CALPUFF model (version 5.711a, level 040716) will be used to calculate 

pollutant concentrations at receptors in each Class I area. Application of CALPUFF 

should, in general, follow the guidance presented in the Interagency Workgroup on Air

Quality Modeling (IWAQM) Phase 2 report (EPA – 454/R98-019) and the EPA Regional 

Haze Regulations and Guidelines for BART Determinations (70 FR 39103). 

Appropriate CALPUFF control file inputs are in Table 4. Note should be taken of 

the basis for several of the recommended CALPUFF inputs. 

• Building downwash effects need not be included. Because of the transport 

distances involved and the fact that most sources have tall stacks, building

downwash is unlikely to have a significant effect on model-predicted 

concentrations 

• Puff splitting is not required. The additional computation time necessary for puff 

splitting is not justified for purposes of BART analyses. 

• Hourly ozone files should be used to define background ozone concentration. 

Data are available from the following sites within the model domain. 

Rocky Mountain NP, CO 

Craters of the Moon NP, ID 

AIRS – Highland UT 

Mountain Thunder, WY 

Yellowstone NP, WY 

Centennial, WY 

Pinedale, WY

The background ozone concentration shown in Table 4 is used only when hourly 

data are missing. 

• A constant background ammonia concentration of 2.0 ppb is specified. This value 

is based upon monitoring data from nearby states and IWAQM guidance.

Experience suggests that 2.0 ppb is conservative in that it is unlikely to

significantly limit nitrate formation in the model computations. 

• MESOPUFF II chemical transformation rates should be used. 

• The species to be modeled should be the seven identified in CALPUFF: SO2, 

SO4, NOx, HNO3, NO3, PM2.5, and PM10-2.5. If ammonia (NH3) is emitted it 

should be added to the species list. In most cases, all pollutants modeled will also 

be emitted, except for HNO3 and NO3. 

12
Concentration calculations should be made for receptors covering the areas of the 

Class I areas being addressed. Receptors in each Class I area will be those designated by

the Federal Land Managers and available from the National Park Service website. 

 

Table 4. CALPUFF Control File Inputs 

Variable Description Value

Input Group 1 

METRUN Control parameter for running all periods in met file 1 

IBYR Starting year 2001

2002 

2003 

XBTZ Base time zone 7 

NSPEC Number of chemical species modeled 7 (or 8) 

NSE Number of species emitted 5 (or 6) 

METFM Meteorological data format 1 

 Input Group 2 

MGAUSS Vertical distribution in near field 1 

MCTADJ Terrain adjustment method 3

MCTSG Subgrid scale complex terrain 0 

MSLUG Elongated puffs 0

MTRANS Transitional plume rise 1

MTIP Stack tip downwash 1 

MSHEAR Vertical wind shear 0 

MSPLIT Puff splitting allowed? 0 

MCHEM Chemical mechanism 1

MAQCHEM Aqueous phase transformation 0 

MWET Wet removal 1

MDRY Dry deposition 1

MDISP Dispersion Coefficients 3

MROUGH Adjust sigma for roughness 0 

MPARTL Partial plume penetration of inversions 1 

MPDF PDF for convective conditions 0 

 Input Group 4 

PMAP Map projection LCC

DGRIDKM Grid spacing 4

13
Table 4. CALPUFF Control File Inputs (continued) 

ZFACE Cell face heights (m) 0 

20

40

100

140

320

580

1020

1480

2220

3500

 Input Group 6 

NHILL Number of terrain features 

 Input Group 7 

0 

Dry Gas Depo Chemical parameters for 

dry gas deposition 

Defaults 

 Input Group 8 

Dry Part. Depo Size parameters for dry 

particle deposition 

 SO4, NO3, PM25

 PM10 

Defaults 

6.5, 1.0 

 Input Group 11 

MOZ Ozone Input option 1 

BCK03 Background ozone – all 

months (ppb) 

44.0 

BCKNH3 Background ammonia – all 

months (ppb) 

2.0 

 Input Group 12 

XMAXZI Maximum mixing height

(m) 

3500 

XMINZI Minimum mixing height

(m) 

50 

14
6.0 POST PROCESSING 

Visibility impacts are calculated from the CALPUFF concentration results using

CALPOST. CALPOST version 5.51, level 030709 should be used; the output from

CALPOST will provide the highest deciview impact on each day from all receptors

within each Class I area modeled. 

For some CALPUFF applications such as deposition calculations, the POSTUTIL

program is used prior to CALPOST. POSTUTIL is also used to repartition total nitrate 

by accounting for ammonia limiting. The ammonia limiting calculation in POSTUTIL 

should not be applied for Wyoming BART modeling. If you believe that ammonia 

limiting is appropriate for a specific BART analysis, justification should be discussed

with the Division prior to its used. 

Visibility calculations by CALPOST for BART purposes use Method 6. This

method requires input of monthly relative humidity factors, f(RH), for each Class I area.

The EPA guidance document provides appropriate data for each area. Table 5 lists

monthly f(RH) factors to use for the Wyoming, Colorado, and South Dakota areas to be 

addressed in BART modeling. The factors shown in Table 5 include averages for the 

adjacent Class I areas, and are within 0.2 units of the Guideline table values for the 

individual Class I areas. 

Natural background conditions as a reference for determination of the delta-dv

change due to a source should be representative of the 20% best natural visibility days. 

EPA BART guidance provides the 20% best days deciview values for each Class I area 

on an annual basis, but does not provide species concentration data for the 20% best 

background conditions. These concentrations are needed for input to CALPOST. 

Annual species concentrations corresponding to the 20% best days were

calculated for each Class I area to be addressed, by scaling back the annual average

concentrations given in Guidance for Estimating Natural Visibility Conditions Under the 

Regional Haze Rule (Table 2-1). A separate scaling factor was derived for each Class I 

area such that, when multiplied by the Guidance table annual concentrations, the 20% 

best days deciview value for that area would be calculated. The scaled aerosol 

concentrations were averaged for the Bridger and Fitzpatrick WAs, and for Wind Cave 

and Badlands NPs, because of their geographical proximity and similar annual 

background visibility. The 20% best days aerosol concentrations to be used for each 

month for Wyoming BART evaluations are listed in Table 6. 

Table 7 is a list of inputs for CALPOST. These inputs should be used for all 

BART visibility calculations. Output from CALPOST should be configured to provide a 

ranked list of the highest delta-deciview values in each Class I area. The 98th percentile 

delta-deciview value and the number of values exceeding 0.5 can then be determined 

directly from the CALPOST output. 

15
Table 5. Monthly f(RH) Factors for Class I Areas 

Month Wind Cave NP

Badlands NP 

Bridger WA

Fitzpatrick WA 

Mt. Zirkel WA 

January 2.65 2.50 2.20

February 2.65 2.30 2.20

March 2.65 2.30 2.00

April 2.55 2.10 2.10

May 2.70 2.10 2.20

June 2.60 1.80 1.80

July 2.30 1.50 1.70

August 2.30 1.50 1.80

September 2.20 1.80 2.00

October 2.25 2.00 1.90

November 2.75 2.50 2.10

December 2.65 2.40 2.10

16
Table 6. Natural Background Concentrations of Aerosol Components for 20% Best Days

for BART Analyses (μg/m3

) 

Aerosol 

Component 

Wind Cave NP 

Badlands NP 

Fitzpatrick WA 

Bridger WA

Mt. Zirkel WA 

Ammonium Sulfate .047 .045 .046 

Ammonium Nitrate .040 .038 .038 

Organic Carbon .186 .178 .179 

Elemental Carbon .008 .008 .008 

Soil .198 .189 .190

Coarse Mass 1.191 1.136 1.141 

17
Table 7. CALPOST Control File Inputs 

Variable Description Value

Input Group 1 

ASPEC Species to Process VISIB

ILAYER Layer/deposition code 1

A,B Scaling factors 0,0

LBACK Add background concentrations? F 

BTZONE Base time zone 7 

LVSO4 Species to be included in extinction T 

LVNO3 T

LVOC F

LVPMC T

LVPMF T

LVEC F

LVBK Include background? T

SPECPMC Species name for particulates PM10 

SPECPMF PM25

EEPMC Extinction efficiencies 0.6

EEPMF 1.0

EEPMCBK 0.6

EESO4 3.0

EENO3 3.0

EEOC 4.0

EESOIL 1.0

EEEC 10.0

MVISBK Visibility calculation method 6

RHFAC Monthly RH adjustment factors Table 5 

BKSO4 Background concentrations Table 6 

BKNO3 Table 6

BKPMC Table 6

BK OC Table 6 

BKSOIL Table 6

BKEC Table 6

BEXTRAY Extinction due to Rayleigh scattering 10.0 

18
19

7.0 REPORTING 

A report on the BART visibility analysis should be submitted that clearly 

compares impacts for post-control emissions to those for baseline emissions. Data for 

baseline and BART scenarios should include both the 98th percentile values and the 

number of days with delta-deciview values exceeding 0.5. Results should be given for 

each model year. 

Table 8 is an example of a recommended format for presentation of model input 

and model results. The example is for baseline conditions; similar tables should be 

provided for each control scenario (SO2, NOx, and PM10) and for the combination of all 

BART controls. Your report tables need not follow the exact format shown in Table 8; 

but the same information should be provided in a concise and clear form. If additional 

scenarios were modeled or you wish to present supplemental information, they should be 

provided in an appendix or separate from the specified final results. 
Table 8. Example Format for Presentation of Model Input and Results 

Baseline Conditions Model Input Data 

Source 

(Unit) 

Description 

And ID 

SO2

Emission 

Rate 

(lb/day) 

NOx

Emission 

Rate 

(lb/day) 

PM2.5

Emission 

Rate 

(lb/day) 

PM10-2.5

Emission 

Rate 

(lb/day) 

SO4

Emission 

Rate 

(lb/day) 

NH3

Emission 

Rate 

(lb/day) 

Location 

Easting 

UTM 

(m) 

Location 

Northing

UTM 

(m) 

Stack 

Height

(m) 

Baseline Visibility Modeling Results 

Name of 2001 2002 2003

Facility 

Class I 

Area 98th

Percentile 

Value 

(dv) 

No. of 

days 

exceeding 

0.5 dv 

98th

Percentile 

Value 

(dv) 

No. of 

days 

exceeding 

0.5 dv 

98th

Percentile 

Value 

(dv) 

No. of 

days 

exceeding 

0.5 dv