## Technical Support Document

for USEPA's Review of

the California Regional Haze Plan's Modeling

for the Best Available Retrofit Technology (BART) Evaluation

Prepared by USEPA Region 9

March 3, 2011Table of Contents

Description Page

List of Tables and Figures 3

List of Commonly Used Acronyms 4

Overview of BART modeling requirements 5

A. Overview of the Califor nia Regional Haze Plan's Best Available Retrofit Technology Modeling Approach 5

B. Model Selection and Applicability 6

C. CALMET 6

D. Emissions Input 7

E. Calpuff/Calmet Model Settings 8

F. Model Evaluation 9

G. Calculation of Visibility Impact 9

H. Results of Subject-to-BART Modeling 12

I. South Coast Air Quality Management District -

RECLAIM Sources Visi bility Impact Analysis. 14

J. Conclusion 18

2List of Tables and Figures

Number Title Page

Tables

Table 1: Results of Subject to BART Analys is in California 13

Table 2: Valero Visibility Impact Calculated with 3 Years of Meteorological Data 13

Table 3: Subject-to BART Sources in the RECLAIM Program 15

Table 4: Visibility Impairment from RECLAIM Sources 18

Figures

Figure 1: Class I areas and subject-to-BART sources for which initial visibility 7 impairment analysis has been conducted.

Figure 2: South Coast AQMP PM2.5 Modeling Domain 16

3List of Commonly Used Acronyms and Abbreviations

AQPM Air Quality Management Plan

BART Best Availabl e Retrofit Technology

CAA Clean Air Act

CARB California Air Resources Board CFR Code of Federal Regulations CRHP California Regional Haze Plan DV (dv) Deciview EPA U.S. Environmental Protection Agency

FDDA four-dimensiona l-data-assimilation FLAG Federal Land Managers' Air Qu ality Related Values Work Group FLM Federal Land Manager FR Federal Register

FS U.S. Forest Service

FWS U.S. Fish and Wildlife Service IMPROVE Interagency Monitoring of Protected Visual Environments IWAQM Interagency Workgr oup on Air Quality Modeling MATES –III Multiple Air Toxics Exposure Study III MM5 Pennsylvania State University/Nati onal Center for Atmospheric Research Mesoscale Model NAAQS National Ambient Air Quality Standards

NCEP National Centers for Environmental Prediction's

NO x Oxides of Nitrogen

NPS National Park Service

NSR New Source Review

PM Particulate Matter PSD Prevention of Significant Deterioration RECLAIM REgional CLean Air Incentives Market SCAQMD South Coast Air Qual ity Management District

SO 2 Sulfur Dioxide TPY (tpy) Tons Per Year TSD Technical Support Document WRAP Western Region al Air Partnership

4Overview of BART mo deling requirements

The Clean Air Act establishes the national goal of eliminating man-made visibility impairment from all Class I areas. As a part of the plan fo r achieving this goal Sect ion 169A(b)(2)(A) of the act requires certain major stati onary sources in existence betw een 1962 and 1977 to be reviewed for BART. Pursuant to federal regulations, stat es have the option of ex empting a BART-eligible source from the BART requirements based on disp ersion modeling demonstrating that the source cannot reasonably be anticipated to cause or contri bute to visibility impairment in a Class I area. According to 40 CFR Part 51, Appendix Y, a BART eligible source is cons idered to “contribute” to visibility impairment in a Class I area if th e modeled 98th percentile change in deciviews is equal to or greater than the “c ontribution threshold.” Any BART-e ligible source determined to

cause or contribute to visibil ity impairment in any Class I ar ea is subject to BART. The EPA

BART Guidelines recommend a contribution thre shold of 0.5 change in deciview be used, although States have the option to establish alternative thresholds . The state of California has opted to use a contribution thresh old of 0.5 change in deciview.

To determine whether a source exceeds the BART contribution threshold, EPA recommends use of the CALMET/CALPUFF modeling system; the ma in components of this modeling system are CALMET (a diagnostic three-dimensional mete orological model), CALPUFF (an air quality dispersion model), and CALPOST (a post-processing package).

A. Overview of the California Regional Haze Plan BART Modeling Approach

To conduct the modeling, California followed the EPA BART guidelines 1 (U.S. EPA, 2005) and the applicable CALMET/CALPUFF mode ling guidance ( IWAQM, 1998; FLAG, 2000 2 ; EPA, 2003c) in effect at the time the analysis was conducted 3 . This included EPA’s March 16, 2006, memorandum “Dispersion Coefficients for Regulatory Air Quality Modeling in CALPUFF” (Atkinson and Fox, 2006). This memo was written by the EPA Office of Air Quality and Planning Standards (OAQPS) Model Clearinghouse Di rector in response to questions from EPA Region 4 on what constitutes the regulatory version of CALPUFF and recommended CALPUFF options for BART mode ling in their region.

1 59 FR 39104, 39170 (July 6, 2005)

2 U.S. Forest Service, National Park Service, and U.S. Fi sh and Wildlife Service. 2010. Federal land managers‘ air quality related values work group (FLAG): phase I report—revised (2010) . Natural Resource Report

NPS/NRPC/NRR—2010/232. National Pa rk Service, Denver, Colorado.

3 California Regional Haze Plan, page C-2, Results of CALMET/CALPUFF BART Modeling for Class I Federal Area Individual Source Attribution Visibility Impairment

5The memo’s modeling recommendations are fo llowed in the protocol for conducting the modeling 4 , except as noted below. Using the pro cedures in the modeling protocol, CARB conducted initial subject-to-BAR T screening analysis modeling to determine which sources contribute significantly to visibility impairmen t at Class I areas. CARB then provided the modeling results to the aff ected districts, and the di stricts used those results, in conjunction other information, to determine whether or not the indi vidual BART-eligible sour ce will be subject to BART control requirements. CARB modeled background visibility conditions corresponding to the annual average visibility. EPA guidance allo ws States to select the characte rization of background conditions for their BART modeling. CA RB also provided mode ling results showing the highest 24 average change in visibility and the 8th highest (98th percentile ) predicted change.

B. Model Selection and Applicability

Relevant guidance (IWAQM, 1998 5 ; FLAG 2000 6 ; EPA, 2003 7 ) states that the CALPUFF model is generally applicable at distances fr om 50 km to at least 200-300 km downwind of a source. Given the large number of Class I areas in the West, most BA RT-eligible stationary sources modeled by CARB were located within 300 km of at least one Class I area.

The CRHP modeling was conducted by CARB using CALPUFF: version 5.754, level 060202, CALMET: version 5.724, level 060414, and CALPOST: version 5.6393, level 060202

C. CALMET

CALMET is a diagnostic meteorolog ical model. For the CRHP, the initial guess wind fields

were based on 12-km resolution MM5 meteorol ogical fields for 2000 and 2002 and 36-km MM5 data for 2001 (i.e., in CALMET IPROG is set to 14). The MM5 files for 2000 were generated by

ARB staff and the MM5 files for 2001 and 2002 were provided by Western Regional Air Partnership (WRAP). Because the MM5 data for the year 2000 were generated specifically for applications in California, CARB believes that the data for this year may be more reliable and more representative of the meteor ological conditions of California.

CALMET Modeling Domain 8

The modeling domain is shown in Figure 1. Also shown are locations of receptors to be placed in Class I areas. It is based on a La mbert Conformal Conic projection. The domain

covers all Class I areas in California and the locations of California’s BART-eligible sources that are required to do detailed mode ling and analysis. The domain also includes

4 CRHP, Appendix 1. Modeling Protocol: CALMET/CALPUFF BART Protocol for Class I Federal Area Individual Source Attribution Visibility Impairment Modeling Analysis.

5 Interagency Workgroup on Air Quality Modeling (IWAQM) Phase 2 Summary Report and Recommendations for Modeling Long Range Transport Impacts (EPA-454/R-98-019)

6 http://www.nature.nps.gov/air/Pubs/pdf/flag/FlagFinal.pdf

7 EPA. 2003. “Revisions to the Guideline on Air 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.

8 CRHP, page C-8.

6Class I areas in nearby states that are pot entially impacted by California BART-eligible sources. The modeling domain is extended by 50-km beyond all sources and Class I areas to capture potential recirculation of pollu tants. The CALMET domain is 1332 km x 1332 km in the longitudinal and me ridional directions, respectively, with 4-kilometer grid resolution. This modeling domain will be used to generate a unified meteorological data

set so that it can be used in CALPUF F modeling for all BART-eligible sources.

Figure 1. Class I areas and subject-to-BART sour ces for which initial visibility impairment analysis has been conducted. 9

D. Emissions Input

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

9 CRHP, page C-8.

7emission rate from the highest emitting day of the meteorological peri od modeled, unless this rate reflects periods start- up, shutdown, or malfunction.” (EPA, 2005) 10

.

The WRAP contractor Eastern Re search Group, Incorporated (ERG) prepared a short list of all facilities in California permitted under Title V of the Clean Air Act that fall into the 26 BART categories.

CARB excluded VOC emissions from the BART –elig ibility evaluation, based its analysis that secondary organic aerosols formed from anth ropogenic VOC emissions are not significant contributors to haze on worst days in California 11

While NOx, SOx, and PM emissions must be evaluated for BART-eligibility, the Regional Haze Rule gives states the discretion to excuse f acilities solely exceeding the threshold for VOC or ammonia provided thatthose pollutants do not contribute to impaired visibility at Class 1 Areas. In Calif ornia, ammonia emissions from area, mobile,

and natural sources exceed those from stati onary sources. Also, since secondary organic aerosols formed from anthropogenic VOC emissi ons are not significant contributors to haze on worst days in California, the State ch ose not to include sources that exceed the threshold for VOCs. When worst days in Calif ornia are driven by or ganic aerosols, they appear to be the result of seasonally high bioge nic emissions from plants or from wildfire

events.

California’s BART-eligible list includes only BART-era units w ith total emissions of NOx, SOx, or PM above the BART threshold, listed below, at a single facility.

1. a PTE <15 TPY for PM emissions, or 2. a PTE <40 TPY of SOx emissions, or

3. a PTE <40 TPY of NOx emissions.

Those emission units at a single f acility that cumulatively emit only the pollutant(s) falling below

these de minimus thresholds were listed but excluded from further review. The emission specifications for the major units for each of th e subject –to BART sources are listed in APPENDIX C, BART Cal-Puff Modeling.

E. Calpuff/Calmet Model Settings

The CALMET and CALPUFF model settings us ed by CARB are listed in the CALMET Parameter Summary 12 and CALPUFF Parameter Summary 13 . The settings complied with EPA’s recommendations for regulatory application of the CALPUFF modeling system in effect at the time of the analysis. The exception is for the IPROG parameter. The EPA default

10 EPA. 2005. “Regional Haze Regulations and 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, FRL7925-9, RIN AJ31.

11 CRHP, page 5-3

12 CRHP, page C-34

13 CRHP, page C-39

8assumes no MM5 data will be used (IPROG=0). In the CARB BART screening analysis, MM5 data were used as an initial-gue ss field (IPROG=14). In Section 6.1.1.10., CALMET Upper Air

Stations 14

, CARB discusses the basis for choosing this option.

The initial analysis will not c onsider upper air observ ational data for mainly two reasons.

The first reason is that a substantial amount of data are missing, and there exists no rigorous method to fill in missing data. Filling in missing data arbitrarily will likely alter the meteorological field generated by the CALMET model. The other reason is that, since the output of the MM5 mesoscale meteorological model provides an adequate coverage of upper air meteorology, neglecting upper air observational data will have an insignificant effect on the CALMET meteorological field. Future an alyses may consider upper air observational

data.

F. Model Evaluation

Calpuff has been evaluated nationally by EPA an d is considered appropriate for long range transport applications. No site specific performance evaluations were performed.

G. Calculation of Visibility Impact

Under the BART guidelines, the measure of th e visibility improvement to be used in comparisons between various control scenarios is the 98 th percentile of impacts are expressed as 24-hour averages of delta deciviews relative to natural background, as estimated using the CALPUFF air quality modeling system. The meani ng of this is described next, followed by particulars of the application of CALPUFF to the BART determination for the CRHP.

Under the RHR, visibility is measured in deciview s. Visibility is traditionally described in terms of visual range in kilometers or miles. Howeve r, the visual range scale does not correspond to how people perceive visibility: a given increase in visual range is perceived differently depending on how good the original visibility wa s (that is, it is not on a linear scale). The deciview scale is designed to a ddress this problem. It is linear with respect to perceived visual changes over its entire range, an alogous to the decibel scale for sound: a given change in deciviews will be perceived as the same amount of visibility change, whatever the original visibility was. The defining equation is: deciviews = 10*ln(b ext / 10), where ln is the natural logarithm, and extinction b ext is the fraction of light scattered out of a viewing path. Extinction increases with the amount of pollution (b ext is in units of 1/Mm, “inverse megameters”). Lower deciview values represent better visibility, more pristine atmosphe res, and greater visual range, while increasing deciview values represent in creasingly poor visibilit y. An increase of 1 deciview corresponds to about a 10% increase in extinc tion. (Deciviews are related to the more traditional visual range according to dv = 10*ln( 391 / visual range)). An eligible BART source with a predicted impact of 0.5 dv or more of impairment in a Class I area“contributes” to visibility impairment and is subjec t to BART. 70 FR 39104, 39121 (July 6, 2005).

14 CRHP, page C-33.

910 Under the BART guidelines, deciviews are esti mated using the CALPUF F air quality model. CALPUFF predicts 24-hour averag e pollutant concentrations based on source emissions and how they disperse in the atmosphere. The CALPUF F modeling includes source emissions of the following visibility-impairing pollutants: SO 2 , SO 4 , NO x , secondary organic aerosol (SOA), fine particulate matter (PMF), coarse particulat e matter (PMC), and elemental carbon (EC). CALPUFF incorporates a semi-empirical chemi cal module that simulates the conversion of SO 2 to particulate sulfate and NO x to particulate nitrate, at a rate dependent on meteorological conditions and background ozone concentrati on. These concentrations are converted to deciviews by the CALPOST post-processo r in two steps. First, the IMPROVE 15 equation is used

to estimate extinction b ext from the predicted concentra tions of various pollutants:

b ext = 3 * f(RH) * [ sulfate ] + 3 * f(RH) * [ nitrate ] + 4 * [ organic mass ] + 10 * [ elemental carbon ] + 1 * [ fine soil ] + 0.6 * [ coarse mass ] + 10

The 10 is for Rayleigh scattering, which is due to the interaction of light with molecules of air itself with no pollutants. The f(RH) is a water gr owth factor for sulfate and nitrate; its value depends on relative humidity (RH), ranging from 1 at low humidity to 18 at 98% humidity. In the second CALPOST step this extinction is conv erted to deciviews, us ing the above defining equation for deciviews. Finally, th e delta deciviews (dv) represents the impact on visibility in deciviews of the source being evaluated, and is also provided by CALPUFF. It is the change, or “delta”, between deciviews w ith and without the source. Un der the BART guidelines, delta

deciviews is the difference be tween deciviews including the imp act of the source and natural background, and deciviews of the natural bac kground alone. Each modeled day and location in

the Class I area will have an associated delt a deciview. For each day, the model finds the maximum visibility impact of all locations (r eceptors) in the Class I area. From among these daily values, the BART guideli nes recommend use of the 98 th percentile, roughly equivalent to

the 8 th highest day, for comparing the base case and the effects of various controls. The 98th percentile is recommended rath er than the maximum value to avoid undue influence from unusual meteorological conditi ons (BART guidelines p. 39121).

15 Interagency Monitoring of Protected Visual Environments (IMPROVE) is a network of monitors in various Class I Areas, established to assess visibility impairment and its causes. The IMPROVE equation is used to converted monitored concentrations into extinction, a measure of visibility. See: http://vista.cira.colostate.edu/improve/The California Regional Haze Plan uses the Ha ze Algorithm II (revised IMPROVE equation) for estimating the deciview values used in this plan 16

.

The Haze Algorithm for calculating Light Extinction ( b ext) weights the Species Mass ( u g/m3) measured at the IMPROVE monitors us ing particle size, humidity, and elevation

as follows:

b Sulfate = 2.2 x f S (RH) x [small SO4] + 4.8 x f L (RH) x [large SO4]

b Nitrate = 2.4 x f S (RH) x [small NO3] + 5.1 x f L (RH) x [large NO3]

b Organic Material Carbon = 2.8 x [Small OM] + 6.1 x [Large OM]

b Elemental Carbon = 10 x [EC]

b Fine Soil = 1 x [Fine Soil]

b Sea Salt = 1.7 x f SS (RH) [Sea salt]

b Coarse Mass = 0.6 x [CM]

b Rayleigh = (Site Specific factor, relate d to elevation, ranging from 7+ to 11+ in California)

b Nitric Oxide gas= 0.33 x [NO2 (ppb)] (not measured at most IMPROVE monitors).

The sum of the weighted extinction values gives the total daily extinction (Total b ext) for each day of measurement:

Total b ext = b Sulfate + b Nitrate + b EC + b OMC + b Soil + b CM + b SS +

b Rayleigh + b NO2

The revised IMPROVE equation ha s five changes: 1) greater completeness though the inclusion of sea salt, which can be important for coastal sites; 2) increased organic carbon mass estimate, based on more recent data for remote areas; 3) Rayleigh scattering using site-specific elevation and temperature, a refinement over the older netw ork-wide constant; 4) separate estimates for small and large particles of visibility impacts a nd humidity-dependent particle size growth rates,

which could affect estimates at the low and high ends; and 5) greater completeness though the inclusion of NO2 (Pitchford, 2006) 17

.

The new equation shows broader scatter overa ll, but less bias in matching visibility measurements under high and low visibility cond itions. That is, though it has a somewhat worse fit considering all the data, it ha s a better fit under visibi lity conditions most relevant to regional haze planning, the best and worst 20% of days. The looser overall fit can cause a slightly different set of days to be the ones chosen as the 20% worst, but the chemical species composition for such days is little change d (IMPROVE technical subcommittee for algorithm review, 2001, pp. 11-12), and so th is makes little difference for assessing the contribution of

16 CRHP, Appendix A., page A-1.

17 Pitchford, Marc, 2006, "New IMPROVE algorithm for estimating light extinction approved for use", The

IMPROVE Newsletter , Volume 14, Number 4, Air Resource Specialists, Inc.; web page: http://vista.cira.colostate.edu/impr ove/Publications/news_letters.htm direct link: http://vista.cira.colostate.edu/improv e/Publications/NewsLetters/IMPNews4thQtr2005.pdf

1112 emission sources to current conditions, and for pr ojecting the effect of emission controls. The split between small and large particles was the main factor in reducing the biases. Another effect of choosing a revised equation with broader scatter of nephelometer measurements (typically resolved to ~5-minute average data) versus IMPROVE particle sampling (24-hour averages every 3 rd -day) is that a typical viewer at a Class I area would be more likely to notice a difference between the visibility condition from the observed nephelometer value and the calculated IMPROVE value, although not critical to the regional haze planning process specified in the RHR.

The organic carbon (OC) measured by the IMPROVE network does not include all organic matter (OM); based on 1970s urban data, a scaling factor of 1.4 is embedded in the old equation to account for the full mass. Based on recent data more relevant to relatively remote Class I areas, the revised IMPROVE equation embeds an OM/OC factor of 1.8. In practice, for the worst days the biggest effect of switching to the revised IMPROVE equation is the increased organic carbon mass, because the worst days are dominated by organic carbon from fires, rather than the sulfates and nitrates that come more from anthropogenic sources.

Review Comment: The revised IMPROVE equation has less bias, is more refined, accounts for more pollutants, incorporates more recent data, and is based on considerations of relevance for the calculations needed for assessing progress under the RHR. EPA believes it is appropriate for the State of California to use the revised IMPROVE equation.

H. Results of Subject-to-BART Modeling

California identified a list of sources to be evaluated by ARB a nd the air districts. 18 The list also summarizes which BART-eligible units needed subject-to-BART visibility modeling and why the others did not. Only one modeled facility, the Valero Refining Company (Valero) operates a refinery in Benicia, in Solano County, had a visibility impact greater than the 0.5 deciview

threshold. 19

18 CRHP, page 5-8, Table 5-2: List of BART-eligible Sources (Emission Units).

19 CRHP, page C-7.Table 1: Results of Subject to BART Analysis in California

BART Eligible Source Analysis Results

the 98th percentile da ily (24-hour) average deciview (dv) Tesoro Refinery Martinez 0.069 dv

Rhodia Sulfuric Acid Plant Martinez 0.092 dv Shell Refinery Martinez 0.169 dv

Searles Industrial 0.208 dv Valero Refinery Benicia

without proposed emission controls with proposed emissions controls 0.758 dv

0.291 dv Conoco Phillips Refinery Rodeo 0.366 dv Chevron Richmond refinery 0.393 dv Coolwater Reliant Dagget 0.489 dv

The visibility impact of the Valero source fo r the year 2000 was 0.758 deciviews at Point Reyes National Seashore. Two emission reduction strategi es were proposed for the Valero facility for evaluation of their visibility impact. The ma ximum 24-hour emissions for normal operations were provided by the Bay Area Air Quality Management District. 20 The results of the visibility impact with one of the reduction strategies are shown in Table 2: Vale ro Visibility Impact

Calculated with Three Year’s Worth of Mete orological Data (with emission reduction strategy g1), and are below the 0.5 deciview threshold fo r each of the three years that were modeled.

Table 2: Valero Visibility Imp act Calculated with Three Year’s Worth of Meteorological Data (with emission reduction strategy g1)

Modeling Year 8 th Highest Visibility Impact (in deciview)

2000 0.225

2001 0.291

2002 0.259

Review Comment (summary of EPA comment s on CRH BART Modeling): CARB conducted initial subject-to-BART screening analysis mode ling for California to determine which sources contribute significantly to visi bility impairment in Class I ar eas. The overall approach followed EPA guidance and modeling procedures in effect at the time of the analy sis and is therefore

20 CRHP, page C-13. One emission reduction strategy (g1) was to reduce SO2, NOx and PM10 emissions from the coker, crude preheat F-101, reduced preheat F-102, and FCCU regenerator R702 that would be routed to a new main stack, and NOx control on units that would be routed to the p30 west stack and the p31 stack.

13acceptable for use in the current regional haze plan. In the South Coast Air Basis, the South Coast Air Quality Management District pr ovided supplemental BART–exemption modeling conducted by the district. A description and eval uation of this additional modeling analysis is

discussed below.

I. South Coast Air Quality Management District RECLAIM Sources Visib ility Impact Analysis.

1. Modeling Approach for South Coast subject-to- BART Sources in the REgional CLean Air Incentives Market (RECLAIM) program.

The visibility impact analysis for the subjec t-to- BART sources in the South Coast Basin

RECLAIM 21 program was conducted in a separate analysis from the CARB CRPH subject to BART analysis. 22 The eight subject-to BART sources in the RECLAIM program, listed in Table 3 below, contribute approximately 50% of th e total RECLAIM program NOx emissions of 27 tons per day, and 65% of the total RECLAI M SOx program emissions of 12 tons per day.

21 CRHP, Page 5-22. The RECLAIM Program in the South Coast Air Quality Management District is designed to generally substitute a cap-and-trade market mechanism fo r a command-and-control regulatory structure in the pursuit of NOx and SOx emissions reductions from major f acilities within the District. The intent of the program is to reduce emissions of these pollutants at a faster rate th an could be achieved by tr aditional methods and at lower

overall cost.

The RECLAIM Program was originally adopted in 1993, and requires three stages of emission reduction by 2011. In the first stage, which extended to 2000, facilities were re quired to compute emissions using historical activity rates and emission factors representing best available retrof it technology (BARCT) in 1993. Facilities were further required to meet facility-wide emission targets based on th ese 1993 BARCT factors by 2000. In the second phase of emission reductions, affected facilities were required to reduce NOx and SOx emissions between 2000 and 2003 by a uniform percentage calculated by the District. RECLAIM rules require that this reduction be sufficient to bring the aggregate of affected facility emissions to attainment targets specified in the 1991 Air Quality Management Plan.

In 2005, the District conducted a study to determine whethe r reductions under these first two phases were equivalent or greater than those that would have been achieved by the application of BARCT rules to all affected facilities. This study concluded that BARCT limits were more restrictiv e in 2005 than in 1993, an d recommended amendments to the RECLAIM program to achieve these new lower leve ls. The RECLAIM rules were amended in 2005 and regulated facilities now must further reduce emissions by 201 1 to achieve facility-wide emission levels equivalent to those represented by 2005 BARCT limits. As a result of the scope of the RECLAIM Program in covering all facilities emitting four or more tons per year of NOx or SOX, and the diligence with which SCAQMD staff have analyzed and compared the benefits of this program to the universal application of BARCT to all stationary sources, the RECLAIM Program can be deemed equivalent in terms of emission reduction to the application of a universal BARCT regulation or the equivalent BART limitation under U.S. EPA’s visibility protection program.

22 Transmittal letter dated June 9, 201 0 from James N. Goldstene, Execu tive Officer, California Air Resources Board, to Jared Blumenfeld Regional Administrator US EPA Region IX with attach ments. RECLAIM Sources Visibility Impact Analysis.

14Table 3: Subject-to BART Sources in the RECLAIM Program BP Refinery (Carson)

California Portland Cement Chevron refinery (El Segundo) Conoco refinery (Carson) Conoco refinery (Wilmington) Exxon Refinery (Torrance) Tesoro refinery (Wilmington) Ultramar refinery

To determine the potential visibility impact from the emissions NOx and SOx from the subject-to –BART sources in the RECLAIM program on the nearby Class I areas of San Gabriel Wilderness, San Gorgonio Wilderness, Joshua Tree National Park, Cucamonga Wilderness, and San Jacinto Wilderness, SCAQMD modeled the co mbined impact of the emission from all sources in the RECLAIM program.

2. 2007 South Coast PM2.5 Air Quality Management Plan Modeling.

The modeling analysis that the SCAQMD conducted for the subject-to-BART for RECLAIM sources used a CAMx simulation, consistent with the particulate modeling used for the South Coast 2007 PM2.5 Air Quality Management Plan. 23 The particulate modeling is discussed in detail in the AQMP, and briefly below:

In the Final 2007 AQMP, CAMx annual av erage PM2.5 modeling simulations were generated for 2005, 2014 and 2020 baseline emissions and 2014 and 2020 controlled

emissions scenarios. The 2005 CAMx simula tion was conducted using baseline monthly temperature and humidity corrected emissi ons, for a weekday, Saturday and Sunday activity profile. Seasonal boundary conditions we re extracted from the Western Regional Air Partnership (WRAP) regional modeling si mulations (initialized from global air quality model output) in support of the Regional Haze Rule demonstrations. The simulations were driven by MM5 meteorological fields; five day-simulations with a one day “ramp-up” period using NC EP model initialization.

CAMx simulations used the same region (5 km squared grid, 280 easting and 3650 northing, 65 by 40 grid cells) as that us ed for the 2003 UAMAERO-LT analyses. The vertical structure was increased to 11 layers (compared with the 5-layer analysis of UAMAERO-LT), but less than the 19 layers used for the MM5 simulations in an effort to conserve computational resour ces. MM5 was used to genera te the meteorological profile for each day in 2005. The MM5 simulations were generated for the larger SCOS97 modeling domain employing a 5 km square grid and fit to the smaller PM2.5 grid.

23 Final 2007 Air Quality Management Plan, June 2007, South Coast Air Quality Management District, Appendix V: Modeling And Attainment Demonstrations, V-1-6, V-1-7.

15Figure 1: South Coast AQMP PM2.5 Modeling Domain 24

The MM5 simulations were initialized from NC EP analyses and run for 5-day increments

without the four-dimensiona l-data-assimilation (FDDA) option. Speciated PM2.5 data measured from the District’s Multiple Air Toxic Evaluation Program (MATES-III) during 2005 provided the charac terization for evaluation and validation of the CAMx annual and episodic demonstrations.

The model performance for the CAMx simulati on was evaluated against t Wilderness he 2005

annual IMPROVE data the Class I areas of San Gabriel Wilderness, San Gorgonio Wilderness,

and Joshua Tree National Park. 25 The 2005 CAMx simulation tended to under-predict IMPROVE observations, especially for ammonium nitrate.

3. Visibility Impairment Test

The visibility analysis assessed the impact of removing all RECLAIM emissions. The eight subject - to - BART sources contribute 56% of the total RECLAIM NOx emissions and 65% of the total RECLAM SOx emissions, so this represen ts a conservative estimate of impact of the emission from the eight subjec t - to - BART sources. The RECLAIM inventory (for all

24 Final 2007 Air Quality Management Plan, June 2007, South Coast Air Quality Management District, Appendix V: Modeling And Attainment Demonstrations, V - 2- 16.

25 Transmittal letter dated June 9, 2010 from James N. Goldstene, Executive Offi cer, California Air Resources Board, to Jared Blumenfeld Regional Administrator US EPA Region IX with attach ments. RECLAIM Sources Visibility Impact Analysis. page D-4.

1617 REACLAIM sources) represents 19% of the total SOx and 3% of the total NOx modeling inventory in the basin.

SCAQMD determined the visibility im pairment from all RECLAIM sources.

The revised IMPROVE visibility equations were used to determine the deciview for each grid in the modeling domain. Th ree sets of runs were genera ted (six total: CAMx with

and without RECLAIM source contribution) using the IMPROVE monitoring site specific functional humidity estimates. The grid level difference in deciview visibility

between model runs was determined for the enti re Basin and later sorted for the principal

Class I areas within the mode ling domain. The analysis was conducted for the simulated annual and worst 20 percent visibility days in the year. 26

The revised IMPROVE equation is discussed in S ection G. Calculation of Visibility Impact,

above.

Review Comment: The revised IMPROVE equation has less bias, is more refined, accounts for more pollutants, incorporates more recent data, and is based on considerations of relevance for the calculations needed for assessing progress under the RHR. EPA believes it is appropriate for the SCAQMD to use the revised IMPROVE equati on in its analysis of the South Coast Basin.

4. Visibility Impact on the Class I Areas near to the South Coast Basin; San Gabriel Wilderness, San Gorgonio Wilderness, Joshua Tree National Park, Cucamonga Wilderness, and San Jacinto

Wilderness.

The grid level difference in visi bility was determined for the Class I areas for the annual and 20% worst visibility days in the year. The visi bility impairment from all RECLAIM sources is shown in Table 4: Visibility Impairment from RECLAIM Sources, below, which summarizes the results of the RECLAIM Sources Visibility Analysis 27 . The maximum impairment from all

RECLAIM sources is 0.244 deciview s at San Gabriel Wilderness. The impact from the subjectto- BART sources in the RECLAIM program would be expected to be lower.

26 Transmittal letter dated June 9, 2010 from James N. Goldstene, Executive Offi cer, California Air Resources Board, to Jared Blumenfeld Regional Administrator US EPA Region IX with attach ments. RECLAIM Sources Visibility Impact Analysis. page D-1.

27 Transmittal letter dated June 9, 2010 from James N. Goldstene, Executive Offi cer, California Air Resources Board, to Jared Blumenfeld Regional Administrator US EPA Region IX with attach ments. RECLAIM Sources Visibility Impact Analysis. Tables 3, 4, 5, 6, and 7, pages D-6 through D-9.Table 4: Visibility Impair ment from RECLAIM Sources

Class I Area Maximum Deciview

Reduction

Annual Maximum Deciview

Reduction

Worst 20%

San Gabriel Wilderness 0.094 0.244

San Gorgonio Wilderness 0.035 0.053

Joshua Tree National Park 28 0.026 0.012

Cucamonga Wilderness 0.113 0.11

San Jacinto Wilderness 0.026 0.18

Review Comment (summary of EPA comments on the South Coast AQMD BART Modeling): The South Coast AQMD conducted initia l subject-to-BART screening analysis modeling for the South

Coast Air Basin to determine which sources contri bute significantly to visibility impairment in Class I areas. The overall approach is acceptabl e for use in the current regional haze plan for the subject - to - BART sources in the RECLAIM program in the South Coast Basin.

J. Conclusion.

California evaluated its BART eligible sources for areas outside of the South Coast Air Basin using CALPUFF/CALMET. SCAQMD supplemented th is analysis with an analysis of subjectto - BART sources in the RECLAIM program us ing modeling based on the particulate modeling

that was the basis for the PM2.5 attainment de monstration in the 2007 Air Quality Management

Plan.

Review Comment (summary of EPA comments on CRHP BART Modeling): The technical work of CARB and the SCAQMD in support of the CRHP was c onsistent with the best practices and science at the time it was performed. It is appropriate for the State of California to use it as the basis for complying with the requirements of the Regional Haze Rule.

28 RECLAIM Source Visibility Impact, page D-9, Table 7 pr esents results for the Deciview Analysis Joshua Tree Wilderness and is erroneously labeled Deciview Analys is for San Jacinto Wilderness. The correct Deciview Analysis for San Jacinto Wilderness is presented in Ta ble 6. Telephone conversa tion between Joe Cassmasi, SCAQMD, and C. Bohnenkamp, USEPA, March 3, 2011.

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