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Summary of LADCO’sRegional Modeling in the Eastern U.S.:Preliminary Results

April 27, 2009MWAQC TAC June 15, 2009

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Background

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Section 110(a)(2)(D) requires SIPs to…

“… contain adequate provisions – (i) prohibiting…any source or other type of emissions activity within the State from emitting any air pollutant in amounts which will –

(I) contribute significantly to nonattainment in,or interfere with maintenance by, any other State with respect to any (NAAQS)…, or

(II) interfere with measures required to be included in the applicable implementation plan for any other State under part C to prevent significant deteriorationof air quality or to protect visibility…”

Note: EGU measures alone are not expected to eliminate significant contribution

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Air Quality Modeling

36 km

Model: CAMx

Domain/Grid: Eastern U.S. (36 km-PM2.5,

12 km-O3)

Base Year: 2005

Meteorology: 2005 (and 2002)

Future Years: 2009,2012,2018 (existing control programs)

12 km

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Scenario C-Years 2009, 2012, and 2018 Emissions

• Base: 2007 CEM emissions data, not IPM

• Growth: Growth factors based on EIA data by NERC region and by fuel type

• Control: All legally enforceable controls identified by states plus other controls expected for compliance with CAIR (i.e., EPA’s NEEDS list)

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Model Results

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PM2.5 AnnualConcentrations

2009

2012 2018

DRAFT DRAFT DRAFT

Based on 2005 meteorology

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PM2.5 DailyConcentrations

2009

2012 2018

DRAFT DRAFT DRAFT

Based on 2005 meteorology

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Ozone 8-HourConcentrations

2009

2012 2018

DRAFT DRAFT DRAFT

Based on 2005 meteorology

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EGU Control Strategies Scenario E Scenario F

(2012) (2018)

NOx 0.125 lb/MMBTU 0.07

SO2 0.25 0.10

Reference: “Options for EGU Controls in the Eastern U.S.: White Paper”, October 3, 2008, State Collaborative Technical Workgroup

NOx SO2

2005 2007 2009-C 2012-C 2018-C 2012-E 2018-F

2005 2007 2009-C 2012-C 2018-C 2012-E 2018-F

Eastern U.S. Annual EGU Emissions (TPY)

11Average Improvement: PM2.5 Annual = 1.0 ug/m3 (Scen. E); 1.1 ug/m3 (Scen. F)

Scenario E (2012) Scenario F (2018) v. Scenario C (2012) v. Scenario C (2018)

PM2.5 Annual: Air Quality Improvement(relative to Scenario C)

DRAFT DRAFT DRAFT

Based on 2005 meteorology

12Average Improvement: PM2.5 Daily = 1.1 ug/m3 (Scen. E); 1.3 ug/m3 (Scen. F)

PM2.5 Daily: Air Quality Improvement(relative to Scenario C)

DRAFT DRAFT DRAFT

Based on 2005 meteorology

Scenario E (2012) Scenario F (2018) v. Scenario C (2012) v. Scenario C (2018)

13Average Improvement: Ozone = 1.6 ppb (Scen. E); 2.4 ppb (Scen. F)

Ozone: Air Quality Improvement(relative to Scenario C)

DRAFT DRAFT DRAFT

Based on 2005 meteorology

Scenario E (2012) Scenario F (2018) v. Scenario C (2012) v. Scenario C (2018)

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Model ResultsSource Apportionment

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Ozone Source Apportionment Results: Source Sectors (2005 base)

Holland, MI Atlanta, GA

New York, NY

Key Finding: Contributions dominatedby mobile sources (at least 60%)

DRAFT DRAFT DRAFT

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Ozone Source Apportionment Results: Source Regions (2005 base)

Holland, MI Atlanta, GA

New York, NY

Key Finding: Contributions dominatedby “home” state and neighboring states

DRAFT DRAFT DRAFT

Based on 2005 meteorology

55%

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PM2.5 Annual Source Apportionment Results: Source Sectors(2012 Scenario C)

New York, NY

Key Findings:• All source categories are important contributors• Relative amount of contribution varies by area

DRAFT DRAFT DRAFT

Based on 2005 meteorology

Detroit MI Atlanta, GA

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PM2.5 Daily Source Apportionment Results: Source Sectors(2012 Scenario C)

DRAFT DRAFT DRAFT

Based on 2005 meteorology

Detroit MI Atlanta, GA

New York, NY

Key Findings:• All source categories are important contributors• Relative amount of contribution varies by area

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PM2.5 Annual Source Apportionment Results: Source Regions(2012 Scenario C)

Detroit MI Atlanta, GA

New York, NY

Key Finding: Contributions dominatedby “home” state and neighboring states

DRAFT DRAFT DRAFT

Based on 2005 meteorology

54%

12%

55%

13%

45%

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PM2.5 Daily Source Apportionment Results: Source Regions(2012 Scenario C)

Detroit MI Atlanta, GA

New York, NY

Key Finding: Contributions dominatedby “home” state and neighboring states

DRAFT DRAFT DRAFT

Based on 2005 meteorology

50%

14%

49%

18%

38%

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Example DC Results

DRAFT

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Example DC Results

DRAFT

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Example DC Results

DRAFT

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Example DC Results

DRAFT

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Key Findings• Model Performance

– PM2.5: Generally reasonable, although organic carbon substantially underestimated, (summer) sulfate underestimated, and (winter) nitrate slightly overestimated

– Ozone: Generally reasonable (mostly within +15%)

• Attainment– Only a few areas not meeting PM2.5 and 85 ppb ozone standards; lots of areas not

meeting for 75 ppb ozone standard– Additional EGU emission reductions effective in lowering PM2.5 and ozone

• Source Apportionment– Source Regions: “Home” state generally has the largest impact; neighbor states

generally have next largest impact (i.e., impacts decrease with distance)– Source Sectors: Mobile sources dominate for ozone, point/mobile/area all important

for PM2.5– Similar "linkages" with either a relative or absolute metric, and a lower significance

threshold brings in more states

• Other:– Despite differences in meteorology, 2002 and 2005 meteorology produce similar

results (with higher concentrations for 2002)