# Appendix A: Analysis of Ambient Air Quality 

# DRAFT Appendix A- 

# 1 

# Appendix A: Analysis of Ambient Air Quality

This Progress Report evaluates the San Joaquin Valley’s (Valley) ambient PM2.5 concentrations since the 2008 PM2.5 Plan through a variety of metrics. The District conducted extensive analysis of ambient air quality data to better understand the nature of observed improvements as well as areas within the data set that have been more resistant to improvement. This Appendix presents the District’ s thorough analysis, which was summarized in Section 3 of this Progress Report.

PM2.5 monitoring began in 1999. The Valley’ s PM2.5 monitoring network is reviewed and described in the District’s A nnual Monitoring Network Plans. 1 

# The District uses ambient air quality data as maintained in EPA’s Air Quality System (AQS), 2 

# the official repository for ambient air quality data. Copi es of official PM2.5 data and design value reports are available upon r equest. PM2.5 data from 2010 ar e preliminary as of the time of these analyses. Data certification for 2010 will be complete in mid-2011. Where possible and applicable, the District includes 2010 data throughout this appendix.

A.1 Design Values Design values are one metric for assessing air quality improvements. Design value calculations are three-year averages that follow U.S. Environmental Protection Agency (EPA) protocols for roundin g, averaging conv entions, determining sufficiency in the number of samples, etc. The 2008 PM2.5 Plan more fully describes this protocol. The results provide consistency and transparency to determine basin-wide attainment for both components of the federal PM2.5 NAAQS: the 24-hour PM2.5 standard of 65 μg/m3, and the annual PM2.5 standar d of 15 μg/m3. If any moni toring site within the air basin has either a 24-hour or annual PM2.5 design value higher than the respective standard, then the entire air basin is designated nonattainment. The 2008 PM2.5 Plan demonstrated that all Valley sites will atta in the 1997 PM2.5 NAAQS by 2015.

Table A-1 shows single-year, 98 th 

# percentile averages, and these values are used to generate the three-year average 24-hour design values in Table A-2. This data is shown graphically in Figure A-1 and A-3. Bakersfield’s 24-hour design values have increased slightly to levels just above t he 24-hour standard. As described in Section 3 of this Progress Report, and as will be documented in this Appendix, wildfires and data handling contribute to Bakersfield’ s resistant 24-hour design values.

Table A-3 shows single-year average PM2.5 concentrations, and these values are used to generate the three-year average annual design values in Table A-4. This data is shown graphically in Figures A-2 and A-4. Most Valley air monitoring sites do not meet the annual PM2.5 standard. The 2008 PM2.5 Plan identified the annual PM2.5

1 

# For more details on the San Joaquin Valley air monitoring sites, refer to San Joaquin Valley Air Pollution Control District Ambient Air Monitoring Network Plan, June 30, 2010 http://www.valleyair.org/aqinfo/Docs/02%20FIN AL%20 2010%20monitoring%20network%20plan.pdf
2 

# U.S. Environmental Protection Agency. Tec hnology Transfer Network; Air Quality System: AQS Web Application. Retrieved from website: http://www.epa.gov/ttn/airs/airsaqs/aqsweb/

# Appendix A-2 

# DRAFT SJVAPCD PM2.5 Progress Report 

# standard of 15 μg/m3 as the pr imary progress indicator, since this will be the more challenging component of the NAAQ S for the Valley to attain.

Average ambient PM2.5 concentrations vary by monitoring site within the Valley. In general, monitoring sites in the northern part of the Valley record the lowest ambient PM2.5 concentrations. The Bakersfield-Planz monitoring site was the design site in the 2008 PM2.5 Plan , meaning it was the site with t he highest PM2.5 design values based on 2004-2006 data. Most of t he Valley’s annual PM2.5 desi gn values have decreased from their 2004-2006 levels, and all of the Valley’s annual PM2.5 design values have decreased since PM2.5 monitoring began. Se ction A-2 of this Appendix presents several caveats to consider in interpreting design values.

Evaluating multiple measures of air quality can provide a broader picture of overall air quality progress. Single-year averages (Tables A-1 and A-3) were lower in 2010 than in 2007 for every monitoring site and for both annual and 24-hour NAAQS levels. Also, in 2010, only two Valley monitoring sites had annual averages above 15 μg/m3, compared to nine monitoring sites above this level in 2008 and all sites above this level in 2000.

A 

# s noted in ARB’s Progress Report on Implementation of PM2.5 SIPs for the South Coast and San Joaquin Valley Air Ba sins and Proposed SIP Revisions , adopted on April 28, 2011, between 2001 and 2010, the number of days considered unhealthy under the Air Quality Index (AQI) in the Va lley has been cut in half (page 12 of ARB’s Progress Report; see also Sectio n 3.1.1 of the District’s Progr ess Report). As explained in section A-3 of this A ppendix (and Section 3 of this Progress Report), for many parameters, all Valley site s are showing important PM2.5 improvements.

Notes on Tables A-1 through A-4:

 2010 data: District staff acquired 2010 data from AQS on March 8, 2011. This data is preliminary and has not yet been fu lly reviewed for quality assurance and control.

 Empty cell: No data or insufficient data

 Asterisk (*): Values do not meet co mpleteness criteria

 Turlock 2008: This site only operated for about si x weeks in 2008. Data for this site and time period is available in AQS. Since this site operated for less than one full quarter in the calend ar year, its data is not representative of an annual average and is therefore not included in annual analysis. However, this data is used for 24-hour average analysis.

 Bakersfield-Golden 2010: This site only operated fo r one week in 2010. Data for this site and time period is available in AQS. Since this site operated for less than one full quarter in the calendar year, its data is not r epresentative of an annual average and is therefore not included in annual analysis. However, this data is used for 24-hour average analysis.Table A-1 EPA AMP 480 Design ValueReport, Single year24-hour PM2.5 98thpercentile values (μg/m3), 1999-2010SJV Monitoring Site199920002001200220032004200520062007200820092010*Stockton79.055.058.050.041.036.044.042.048.061.640.434.1*Modesto100.071.069.069.047.045.055.052.057.453.954.533.6*Turlock67.453.139.0Merced91.960.049.355.144.243.048.343.852.754.045.235.5Fresno-1st120.090.075.075.056.052.071.051.067.057.455.848.8Fresno-Winery64.861.571.949.749.471.255.057.444.548.237.0Clovis59.272.571.553.248.152.463.051.360.949.049.044.3Corcoran53.055.189.565.142.249.474.550.157.947.953.446.8Hanford30.5*Visalia114.0103.096.070.047.054.065.050.059.762.153.936.3Bakersfield-Golden95.393.995.980.451.953.974.964.467.760.868.661.5Bakersfield-California97.492.794.973.048.361.563.260.573.064.566.753.3Bakersfield-Planz76.590.666.847.547.666.464.772.272.365.556.2*Please see table notes on page A-2 of this appendixTable A-2 EPA AMP 480 Design Value Report, 24-hour PM2.5 Design Values (three-year averages,μg/m3) , to becompared to standard of 65 μg/m3SJV Monitoring Site1999-20012000-20022001-20032002-20042003-20052004-20062005-20072006-20082007-20092008-2010*Stockton64545042404145515045Modesto80706254495155545547Turlock53Merced67555047454548505145Fresno-1st95806961605863586054Fresno-Winery63666157575961525043Clovis68665851555658545347Corcoran66706652555861525349HanfordVisalia104907157555658575951Bakersfield-Golden95907662606469646664Bakersfield-California95877261586266666862Bakersfield-Planz84786854546068707065Please see table notes on page A-2 of this appendixAppendix A: Analysis of Ambient Air QualityDRAFTAppendixA-3Appendix A-4DRAFTSJVAPCD PM2.5 Progress ReportTable A-3 EPA AMP 480 Design Value Report, Single Year Annual Mean PM2.5 Concentrations (μg/m3), 1999-2010SJV Monitoring Site199920002001200220032004200520062007200820092010*Stockton19.715.513.916.713.613.212.513.112.914.411.311.0*Modesto24.918.715.618.714.513.613.914.815.016.013.012.7*Turlock16.112.5*Merced22.616.714.5*18.715.715.214.114.815.214.9*13.611.2Fresno-1st27.624.519.821.517.816.316.716.818.817.415.113.0Fresno-Winery18.418.621.317.817.016.917.616.816.514.613.4Clovis19.816.318.016.218.5*16.416.316.416.416.218.314.7Corcoran14.3*16.419.221.516.217.417.516.918.415.817.717.9Hanford13.4*Visalia27.623.922.523.218.217.018.818.820.419.816.013.6Bakersfield-Golden26.222.621.824.119.618.219.118.619.917.920.0Bakersfield-California23.822.521.222.717.118.918.018.722.021.919.014.2Bakersfield-Planz20.320.823.517.817.419.819.321.823.522.517.6Please see table notes on page A-2 of this appendixTable A-4 EPA AMP 480 Design Value Report, Annual PM2.5 DesignValues (three-year averages,μg/m3), to becompared to standard of 15 μg/m3Monitoring Site1999-20012000-20022001-20032002-20042003-20052004-20062005-20072006-20082007-20092008-2010*Stockton16.415.314.714.513.112.912.813.512.912.2Modesto19.717.716.215.614.014.114.615.314.713.9TurlockMerced17.916.616.316.515.014.714.715.014.513.2Fresno-1st24.021.919.718.616.916.617.417.717.115.2Fresno-Winery18.519.419.218.717.217.217.117.016.014.9Clovis18.016.817.617.017.116.416.416.317.016.4Corcoran19.019.018.417.017.217.617.017.317.1Hanford13.4Visalia24.723.221.319.518.018.219.319.718.816.5Bakersfield-Golden23.622.821.820.619.018.619.218.819.3Bakersfield-California22.522.120.319.618.018.519.620.921.018.4Bakersfield-Planz21.520.719.618.418.920.321.522.621.2Please see table notes on page A-2 of this appendix

# Figure A-1 2 4-hour PM2.5 Design Values from 2001 (1999-2001 average) to 2010 (2008-2010 average)

Bakersfield-Planz

0 20 40 60 80 100 120

1999- 2001 2000- 2002 2001- 2003 2002- 2004 2003- 2005 2004- 2006 2005- 2007 2006- 2008 2007- 2009 2008- 201024-Hr PM2.5 Design Value (μg/m3)

PM2.5 NAAQS of 65



# Bakersfield-California

0 20 40 60 80 100 120

1999- 2001 2000- 2002 2001- 2003 2002- 2004 2003- 2005 2004- 2006 2005- 2007 2006- 2008 2007- 2009 2008- 201024-Hr PM2.5 Design Value (μg/m3)

PM2.5 NAAQS of 65

2010 data is preliminary and has not yet been fully reviewed for quality assurance and control.



# Bakersfield-Golden

0 20 40 60 80 100 120

1999- 2001 2000- 2002 2001- 2003 2002- 2004 2003- 2005 2004- 2006 2005- 2007 2006- 2008 2007- 2009 2008- 201024-Hr PM2.5 Design Value (μg/m3)

PM2.5 NAAQS of 65



# Visalia

0 20 40 60 80 100 120

1999- 2001 2000- 2002 2001- 2003 2002- 2004 2003- 2005 2004- 2006 2005- 2007 2006- 2008 2007- 2009 2008- 201024-Hr PM2.5 Design Value (μg/m3)

PM2.5 NAAQS of 65 μg/m3

2010 data is p reliminar y and has not y et been full y reviewed for q ualit y assurance and 

# Corcoran

0 20 40 60 80 100 120

1999- 2001 2000- 2002 2001- 2003 2002- 2004 2003- 2005 2004- 2006 2005- 2007 2006- 2008 2007- 2009 2008- 201024-Hr PM2.5 Design Value (μg/m3)

PM2.5 NAAQS of 65 μg/m3

2010 data is p reliminar y and has not y et been full y reviewed for q ualit y



# Fresno-Winery

0 20 40 60 80 100 120

1999- 2001 2000- 2002 2001- 2003 2002- 2004 2003- 2005 2004- 2006 2005- 2007 2006- 2008 2007- 2009 2008- 201024-Hr PM2.5 Design Value (μg/m3)

PM2.5 NAAQS of 65



# Fresno-First

0 20 40 60 80 100 120

1999- 2001 2000- 2002 2001- 2003 2002- 2004 2003- 2005 2004- 2006 2005- 2007 2006- 2008 2007- 2009 2008- 201024-Hr PM2.5 Design Values (μg/m3)

PM2.5 NAAQS of 65

2010 data is preliminary and has not yet been fully reviewed for quality



# Clovis

0 20 40 60 80 100 120

1999- 2001 2000- 2002 2001- 2003 2002- 2004 2003- 2005 2004- 2006 2005- 2007 2006- 2008 2007- 2009 2008- 201024-Hr PM2.5 Design Value (μg/m3)

PM2.5 NAAQS of 65 μg /m3

2010 data is p reliminar y and has not y et been full y reviewed for q ualit y assurance



# Appendix A: Analysis of Ambient Air Quality 

# DRAFT Appendix A- 

# 5

# Figure A-1 (continued) 24-hour PM2.5 Design Values from 2001 (1999-2001 average) to 2010 (2008- 2010 average)

Merced

0 20 40 60 80 100 120

1999- 2001 2000- 2002 2001- 2003 2002- 2004 2003- 2005 2004- 2006 2005- 2007 2006- 2008 2007- 2009 2008- 201024-Hr PM2.5 Design Values (μg/m3)

PM2.5 NAAQS of 65 μg /m3

2010 data is p reliminar y and has not y et been full y reviewed for q ualit y assurance



# Modesto

0 20 40 60 80 100 120

1999- 2001 2000- 2002 2001- 2003 2002- 2004 2003- 2005 2004- 2006 2005- 2007 2006- 2008 2007- 2009 2008- 201024-Hr PM2.5 Design Values (μg/m3)

PM2.5 NAAQS of 65 μg /m3

2010 data is preliminary and has not yet been fully reviewed for quality



# Stockton

0 20 40 60 80 100 120

1999- 2001 2000- 2002 2001- 2003 2002- 2004 2003- 2005 2004- 2006 2005- 2007 2006- 2008 2007- 2009 2008- 201024-Hr PM2.5 Design Values (μg/m3)

PM2.5 NAAQS of 65 μ g /m3

2010 data is preliminary and has not yet been fully reviewed for quality



# Appendix A-6 

# DRAFT SJVAPCD PM2.5 Progress Report

# Figure A-2 A nnual PM2.5 Design Values fr om 2001 (1999-2001 average) to 2010 (2008-2010 average)

Bakersfield-Planz

10 12 14 16 18 20 22 24 26

1999- 2001 2000- 2002 2001- 2003 2002- 2004 2003- 2005 2004- 2006 2005- 2007 2006- 2008 2007- 2009 2008- 2010Annual PM2.5 Design Value (μg/m3)

PM2.5 NAAQS of 15.0



# Bakersfield-California

10 12 14 16 18 20 22 24 26

1999- 2001 2000- 2002 2001- 2003 2002- 2004 2003- 2005 2004- 2006 2005- 2007 2006- 2008 2007- 2009 2008- 2010Annual PM2.5 Design Value (μg/m3)

PM2.5 NAAQS of 15.0 μg/m3

2010 data is preliminary and has not yet been fully reviewed for quality assurance and



# Bakersfield-Golden

10 12 14 16 18 20 22 24 26

1999- 2001 2000- 2002 2001- 2003 2002- 2004 2003- 2005 2004- 2006 2005- 2007 2006- 2008 2007- 2009 2008- 2010Annual PM2.5 Design Value (μg/m3)

PM2.5 NAAQS of 15.0 μg/m3



# Visalia

10 12 14 16 18 20 22 24 26

1999- 2001 2000- 2002 2001- 2003 2002- 2004 2003- 2005 2004- 2006 2005- 2007 2006- 2008 2007- 2009 2008- 2010Annual PM2.5 Design Value (μg/m3)

PM2.5 NAAQS of 15.0 μg /m3

2010 data is preliminary and has not yet been fully reviewed for quality assurance and control. 

# Corcoran

10 12 14 16 18 20 22 24 26

1999- 2001 2000- 2002 2001- 2003 2002- 2004 2003- 2005 2004- 2006 2005- 2007 2006- 2008 2007- 2009 2008- 2010Annual PM2.5 Design Value (μg/m3)

PM2.5 NAAQS of 15.0 μg /m3

2010 data is preliminar y and has not y et been full y reviewed for qualit y assurance and control.



# Fresno-Winery

10 12 14 16 18 20 22 24 26

1999- 2001 2000- 2002 2001- 2003 2002- 2004 2003- 2005 2004- 2006 2005- 2007 2006- 2008 2007- 2009 2008- 2010Annual PM2.5 Design Value (μg/m3)

PM2.5 NAAQS of 15.0 μg/m3



# Fresno-First

10 12 14 16 18 20 22 24 26

1999- 2001 2000- 2002 2001- 2003 2002- 2004 2003- 2005 2004- 2006 2005- 2007 2006- 2008 2007- 2009 2008- 2010Annual PM2.5 Design Value (μg/m3)

PM2.5 NAAQS of 15.0 μg /m3

2010 data is preliminary and has not yet been fully reviewed for quality assurance and control.



# Clovis

10 12 14 16 18 20 22 24 26

1999- 2001 2000- 2002 2001- 2003 2002- 2004 2003- 2005 2004- 2006 2005- 2007 2006- 2008 2007- 2009 2008- 2010Annual PM2.5 Design Value (μg/m3)

PM2.5 NAAQS of 15.0 μg /m3

2010 data is p reliminar y and has not y et been full y reviewed for q ualit y assurance and



# Appendix A: Analysis of Ambient Air Quality 

# DRAFT Appendix A- 

# 7

# Figure A-2, (continued) Annual PM 2.5 Design Values from 2001 (1999-2001 average) to 2010 (2008-2010 average)

Merced

10 12 14 16 18 20 22 24 26

1999- 2001 2000- 2002 2001- 2003 2002- 2004 2003- 2005 2004- 2006 2005- 2007 2006- 2008 2007- 2009 2008- 2010Annual PM2.5 Design Value (μg/m3)

PM2.5 NAAQS of 15.0 μg /m3

2010 data is preliminary and has not yet been fully reviewed for quality assurance and control.



# Modesto

10 12 14 16 18 20 22 24 26

1999- 2001 2000- 2002 2001- 2003 2002- 2004 2003- 2005 2004- 2006 2005- 2007 2006- 2008 2007- 2009 2008- 2010Annual PM2.5 Design Value (μg/m3)

PM2.5 NAAQS of 15.0 μg /m3

2010 data is preliminary and has not yet been fully reviewed for quality assurance and



# Stockton

10 12 14 16 18 20 22 24 26

1999- 2001 2000- 2002 2001- 2003 2002- 2004 2003- 2005 2004- 2006 2005- 2007 2006- 2008 2007- 2009 2008- 2010Annual PM2.5 Design Value (μg/m3)

PM2.5 NAAQS of 15.0 μg/ m 3

2010 data is p reliminar y and has not y et been full y reviewed for q ualit y assurance and control.



# Appendix A-8 

# DRAFT SJVAPCD PM2.5 Progress Report

# Figure A-3 P M2.5 24-hour Design Value Comparison, 2002 (2000-2002 Average) and 2010 (2008-2010 Average)

Figure A-4 A nnual PM2.5 Design Value Comparison, 2002 (2000-2002 Average) and 2010 (2008-2010 Average)

Appendix A: Analysis of Ambient Air Quality 

# DRAFT Appendix A- 

# 9

# Figure A-5 Bakersfield Annual Design Values Within Standard Deviation

y = 0.5866x - 1157.2
R 2 

# = 0.7053



# 0 5 10 15 20 25 30

2003 2004 2005 2006 2007 2008 2009 2010Annual Mean PM2.5 Concentration - μg/m3


# Standard Error Bars

Trend Line



# A.2 Factors Affecting Design Values Some recent design values do not reflect the expected PM2.5 prog ress, but official design values alone do not necessarily pr ovide for the best or most complete understanding of air quality trends. Anal ysis shows that a few unusual issues overwhelm ed the Valley’s si gnificant emissions reductions to increase certain design values. The purpose of this analysis is not to excuse the Valley from additional work to improve air quality, but to better inform the Dis trict on what types of additional work will be most effective.

A.2.1 Monitor types The District and ARB presently use three type s of PM2.5 monitors in the Valley:

 Filter-based Federal Reference Me thod (FRM), defined as the standard for data col lection;

 Real-time Beta-attenuation method (BA M) monitors designated as federal equivalent method (FEM) ( hereafter BAM/FEM); and

 Ordinary BAMs, not designated FEM (hereafter referred to as BAM)

Only FRM and BAM/FEM monitors produce data that is suitable for comparison with the NAAQS. Real-time monitors (BAM/FEM and BAM) produce hourly measurements that the District uses every day to produce da ily air quality forecasting, wood burning prohibitions, public health notifications, and Real-time Air Advisory Network (RAAN) notifications for schools.

Appendix A-10 

# DRAFT SJVAPCD PM2.5 Progress Report

# Appendix A: Analysis of Ambient Air Quality 

# DRAFT Appendix A- 

# 11 

# The District’s Annual Monitoring Network Plans summarize the types of monitors used at Valley air monitoring sites. The District is considering replacing some PM2.5 FRMs with BAM/FEMs, due to FRM maintenance and part replacement difficulties. Historical data shows that FRM and FEM dat a are not truly equivalent in the Valley, and therefore monitor type may impact design values. This issue will be analyzed further in future Monitoring Network Plans and PM2.5 attainment plans.

A.2.2 Effects of Exceptional Events on P M2.5 Data With proper documentation and EPA concu rrence, data influenced by exceptional events can be excluded from official design value calculations. 3 

# The Valley has experienced three main types of except ional events: wildfires, high winds, and fireworks. Exceptional event s are not reasonably preventable or controllable, so it is inappropriate to use data without recognition of these circumstances. The District and ARB limit the submittal of documentation for these events, and EPA generally reviews only those requests that will directly affect an area’s attainment st atus. Even without formal submittal, the District tracks these events and their impact on design values as part of its ongoing air quality analysis. In it s effort to more accu rately characterize ambient PM2.5 concentrations , the District evaluated the Valley’s PM2.5 data with careful consideration of exc eptional events, including thos e not formally submitted to EPA.

A.2.2.1 PM2.5 Exceptional Event Docu m entation Submitted to EPA
The District submitted documentation for exc eptional events of fi reworks and wildfires that occurred in the summers of 2007 and 2 008. If EPA approves this documentation, data from those events will be excluded from official design value calculations.

On July 4 th 

# and 5 th 

# , 2007, hourly PM2.5 concentrations at Fresno-First and BakersfieldCalifornia coinciding with fire works activity. In the summer of 2008, just months after adoption of the 2008 PM2.5 Plan , California experienced a re cord number of wildfires, with 5,812 fires burning 1,339,839 acres. The resulting emissions, most from outside the Valley, caused serious public health impacts and unprecedented levels of PM2.5 and ozone in the Valley and th roughout the state. Valley PM2.5 concentrations were elevated for a number of da ys during this period.

These exceptional events caused the Valley’ s PM2.5 design values to be higher than normal. Table A-7 summarizes the affects of removing this data from official design values. The prolonged 2008 wildfire event has a noticeable impact on design values, especially for monitoring sites closest to the wildfire in the northern portion of the Valley. The largest difference occurred at the Sto ckton air monitoring site, where the 24-hour value was 61.6 μg/m3 with the exceptional event data incl uded, and 48.2 μg/m3 with that data removed. Excludi ng days that were impacted by smoke reduces the PM2.5 annual average design val ue by 0.7 μg/m3.

3 

# EPA’s Treatment of Air Quality Monitoring Data Influence by Exceptional Events, Codified in 40 CFR Chapter 1 (7- 1-2010 Edition), Section 50.14.

# Table A-5 Exceptional Event Impact on 24-hour and Annual Mean PM2.5 Values

Year Site Annual Mean Before EE Concurrence Annual Mean with EPA EE Concurrence Difference μ g/m 3 

# 24-hour Mean Before EE Concurrence 24-hour Mean with EPA EE Concurrence Difference μ g/m 3



# 2008 Stockton 14.4 12.9 -1.5 61.6 48.2 -13.4 Modesto 16.0 14.7 -1.3 53.3 49.5 -3.8 Merced 14.9 13.9 -1.0 51.1 45.2 -5.9 Clovis 16.0 14.8 -1.2 49.0 49.0 0.0 Fresno-1st 17.4 16.1 -1.3 57.4 54.4 -3.0FresnoWinery 16.5 15.6 -0.9 44.5 44.5 0.0

Visalia 21.0 19.5 -1.5 62.1 55.5 -6.6 BAK-CA 21.9 20.0 -1.9 64.5 63.4 -1.1 BAK-Planz 23.5 22.8 -0.7 72.3 72.3 0.0
2007 Fresno 1st 18.8 18.4 -0.4 67.0 66.0 -1.0 BAK-CA 22.0 21.8 -0.2 73.0 73.0 0.0



# A.2.2.2 High-Wind Events Effects on PM2.5 Data The District has also been evaluating the po ssible PM2.5 impact of high wind events, though the District has not submitted formal PM2.5 exc eptional event document to EPA for these events at this time. In some most of these cases, the District submitted formal PM10 exceptional event documentation fo r these dates and monitors. Geologic particulates are the primary component of elevated PM10 during high wind events, but the geologic component of PM2.5 is still under investigation.

The District has observed similarities in hourly increases in PM10 and PM2.5 during certain high wind events, though. High-win d events affected Bakerfield-Planz on January 4, 2008 and October 13, 2009, and co rresponding PM2.5 measurements were unusually high at 100.3 μ g/m 3 

# and 167.7 μ g/m 3 

# , respectively. Table A-8 summarizes the impact of the 2008 and 2009 events on Bakersfi eld-Planz design values. Similarly, the District expects to docum ent a PM10 exceptional event affecting Bakersfield-Planz on April 11, 2010. PM2.5 levels were also much higher than normal in conjunction with this event, and excluding this single day would decrease the 2008-2010 24-hour design value by about 10 μg/m3 (as mentioned in Sect ion 3.2.2 of this Progress Report).

Appendix A-12 

# DRAFT SJVAPCD PM2.5 Progress Report

# Appendix A: Analysis of Ambient Air Quality 

# DRAFT Appendix A- 

# 13 

# Table A-6 High-Wind Event Influen ce on Bakersfield–Planz Design Value
24-hour Design Values μ g/m 3 

# Annual Design Values μ g/m 3 

# High-Wind Event
Included Excluded Included Excluded 2007* 72.2 72.2 21.8 21.8 2008 72.3 61.0 23.5 22.6 2009 65.5 65.4 22.5 21.4 Design Value 2007-2009 

# 70 66 22.6 21.9 Difference 4 0.7 * - No high wind events were captured in the 2007 data set.



# A.3 PM2.5 Trends Design values summarize a site’s large amount s of data with just tw o concentrations: an annual average, and a value representing 24 -hour peaks. Thes e parameters are important for attainment determinations, but design values alone will not reveal how public health might be impacted by PM2.5 from day-to-day or throughout the day. The District’s multi-faceted analysis of all avail able Valley PM2.5 data reveals patterns of seasonal variations and hourly fluctuations and, in general, demonstrates air quality improvements between 2005 and 2010. The District also investigated potential emissions source changes and PM2.5 sample s peciation, where available, to consider potential causes for the Valley’s PM2.5 patterns.

A.3.1 Daily PM2.5 Trends
As mentioned in section A.2.2 of this appendix, m any of the Valley ’s air monitoring sites use real-time PM2.5 monitors, which pr oduce hourly PM2.5 m easurements. The District uses this data every day to produce daily air quality forecasting, wood burning prohibitions, public health notifications, and Real-time Air Advisory Network (RAAN) notifications for schools. The District comp iled long-term diurnal profiles to analyze how PM2.5 concentrations vary throughout the day at each Valley monitoring site (Figure A6).

The District found that PM2. 5 concentrations generally peak in the early morning and late evening, with lower concentrations during t he middle of the day. From year to year, this general pattern has remained consistent for most sites, but the magnitude of peaks have generally decreased to lower PM 2.5 concentrations overall.

Two notable exceptions to this typical patte rn are sites in Fresno and Corcoran. Data from the Fresno 1 st 

# Street site, as shown in Figure 4-4, shows more evening improvement, “flattening” the evening peak. Rule 4901 wood burning prohibitions are most likely generating this progr ess in evening PM2.5 levels in Fresno. The profile of measurements from Corcoran, on the other hand, shows t he development of a mid-day peak, which is higher than the evening peak in 2009. The District will continue to analyze this finding as more data becomes ava ilable to determine if there could be new source activity that may be impacting these daily patterns.

# Figure A-6 Average Annual PM2.5 Di urnal Profiles by Year by Site

Stockton

0 5 10 15 20 25 30 35 40

0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 HourAnnual Avg Hourly Concentration (μg/m3)



### 2006 2007 2008 2009 2010 2010 data is p reliminar y and has not y et been full y reviewed for q ualit y assurance and control.



# Modesto

0 5 10 15 20 25 30 35 40

0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 HourAnnual Avg Hourly Concentration (μg/m3)



### 2002 2003 2004 2005 2006 2007 2008 2009 2010 2010 data is p reliminar y and has not y et been full y reviewed for q ualit y assurance and control.



# Turlock

0 5 10 15 20 25 30 35 40

0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
HourAnnual Avg Hourly Concentration (μg/m3)



### 2007 2008 2009 2010 2010 data is p reliminar y and has not y et been full y reviewed for q ualit y assurance and control. 

# Fresno-First

0 5 10 15 20 25 30 35 40



## 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
HourAnnual Avg Hourly Concentration (μg/m3)



### 2002 2003 2004 2005 2006 2007 2008 2009 2010 2010 data is preliminary and has not yet been fully reviewed for quality assurance and control.



# Clovis

0 5 10 15 20 25 30 35 40

0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
HourAnnual Avg Hourly Concentration (μg/m3)



### 2007 2008 2010 2010 data is preliminary and has not yet been fully reviewed for quality assurance and control.



# Corcoran

0 5 10 15 20 25 30 35 40



### 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 HourAnnual Avg Hourly Concentration (μg/m3)



### 2007 2008 2009 2010 2010 data is p reliminar y and has not y et been full y reviewed for q ualit y assurance and control.



# Appendix A-14 

# DRAFT SJVAPCD PM2.5 Progress Report

# Figure A-6 (continued) Average Annual PM 2.5 Diurnal Profiles by Year by Site

Visalia

0 5 10 15 20 25 30 35 40

0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 HourAnnual Avg Hourly Concentration (μg/m3)



### 2003 2004 2005 2006 2007 2008 2009 2010 2010 data is preliminary and has not yet been fully reviewed for quality assurance and control.



# Ash Mountain

0 5 10 15 20 25 30 35 40

0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 HourAnnual Avg Hourly Concentration (μg/m3)



### 2009 2010 2010 data is p reliminar y and has not y et been full y reviewed for q ualit y assurance and control.



# Bakersfield - California

0 5 10 15 20 25 30 35 40

0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
HourAnnual Avg. Hourly Concentration (μg/m3)



### 2002 2003 2005 2006 2007 2008 2009 2010 2010 data is preliminary and has not yet been fully reviewed for quality assurance and control.



# Appendix A: Analysis of Ambient Air Quality 

# DRAFT Appendix A- 

# 15

# A.3.2 Seasonal PM2.5 Trends The Valley’s PM2.5 concentrations vary throughout the year. PM2.5 levels are typically highest dur ing the winter months as a result of low-level inversion layers that trap pollution in the atmosphere and increased PM2.5 emissions fr om residential wood burning and other sources. However, since the 2008 PM2.5 Plan was adopted, the Valley has experienced some of the cleanest winters on record, as discussed in Section 3.1.1 of this Progress Report.

The District analyzed the Valley’s long- term seasonal PM2.5 variations based on quarterly averages, which are the basis fo r annual average design value calculations (Figure A-7). First quarter (January-March) and fourth quarter (October-December) show significant improvem ents, and Rule 4901 wood bu rning prohibitions from November through February are a likely driver for much of this improvement. Despite this improvement, the Valley’s third quar ter (July-September) averages have not decreased. In some years, third quarter av erage increased. At least part of these increases is likely attributable to late summer wildfire smoke, particularly in 2008. While third quarter PM2.5 concentrations are not the year’s highest values, an increase in this quarter impacts annual averages, somewhat masking the improvement seen during other times of the year. The District will c ontinue to analyze possible emissions sources that could be disproportionally impacting third quarter emissions.

Appendix A-16 

# DRAFT SJVAPCD PM2.5 Progress Report

# Figure A-7 PM2.5 Annual Mean by Monitor Site by Quarter

1st Quarter

0 10 20 30 40 50 60

1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010μg/m3



### Stockton Modesto Merced Fresno 1st Fresno Pacific Clovis Visalia Corcoran BFL-Gold BFL-Ca BFL-Planz



# 3rd Quarter

0 10 20 30 40 50 60

1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010μg/m3



### Stockton Modesto Merced Fresno 1st Fresno Pacific Clovis Visalia Corcoran BFL-Gold BFL-Ca BFL-Planz 

# 2nd Quarter

0 10 20 30 40 50 60

1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010μg/m3



### Stockton Modesto Merced Fresno 1st Fresno Pacific Clovis Visalia Corcoran BFL-Gold BFL-Ca BFL-Planz



# 4th Quarter

0 10 20 30 40 50 60

1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010μg/m3



### Stockton Modesto Merced Fresno 1st Fresno Pacific Clovis Visalia Corcoran BFL-Gold BFL-Ca BFL-Planz



# A.3.3 Annual PM2.5 Trends Table A-3 presents single year annual aver age PM2.5 concentrations. While a 3-year design value can mask years of very high or very low PM2.5 concentrations, single year annual average trends can make progress or issues more apparent. Figure A-8 shows that overall, despite year-to-year vari ations, the Valley’s annual average PM2.5 concentrations are decreasing. In 2010, onl y two monitoring sites had annual averages above 15 μg/m3, the level of the annual NAAQS.

Appendix A: Analysis of Ambient Air Quality 

# DRAFT Appendix A- 

# 17

# Figure A-8 Annual Average PM2. 5 Concentrations Decreasing



# Annual Average PM2.5 Concentrations

0 5 10 15 20 25 30

199 9 20 00 20 01 20 02 2 003 2 004 2 005 200 6 200 7 2008 20 09 20 10



# YearPM2.5 Concentration (μg/m3)



# Stockton Modesto Merced Fresno-1st Fresno-Winery Clovis Corcoran Visalia Bakersfield-Golden Bakersfield-California Bakersfield-Planz



# A.3.4 Days Over the 24-hour PM2.5 Standards

The number of days over the level of the PM2.5 NAAQS is another indicat or of PM2.5 progress, though it would not be used for atta inment determinations. Figure A-9 shows a basin-wide count of the number of days above the level of both the 1997 and 2006 24- hour average PM2.5 NAAQS (65 μg/m3 and 35 μg/m3, respectively). These counts have been normalized to account for the varying sampling schedules of the Valley’s 1- in-6-day, 1-in-3-day, and daily PM2.5 monito rs. Since the calculation form of the 24- hour NAAQS is a 98 th 

# percentile standard, per monitori ng site, an area could attain the NAAQS even where the basin- wide exceedance day count s hows a few days over the level of the NAAQS.

Figure 9 shows that 2009 and 2010 had fewer exceedance days than 2007 and 2008. Also, 2010 had the lowest number of days ov er the level of t he 2006 NAAQS since monitoring began.

Appendix A-18 

# DRAFT SJVAPCD PM2.5 Progress Report

# Figure A-9 Days over the level of the 24-hour NAAQS

Pro g ress towards 24-hour PM2.5 standards: Days over the level of the NAAQS

0 10 20 30 40 50 60 70 80 90 100

2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

YearNumber of days, Basin-wide total 

# Days over 35 μg/m3 (2006 NAAQS) Days over 65 μg/m3 (1997 NAAQS)



# A.3.5 Ongoing Analysis of PM2.5 S ources and Species Bakersfield-Planz is the Valley’s design site , meaning it has the Valley’s highest PM2.5 design values. As discussed in Section 3 and this Appendix, some of Planz’s PM2.5 data analysis is influenced by exceptional event s. Additionally, in some of the District’s analyses, Planz patterns differ from patterns seen at other monitoring sites, even those seen at another Bakersfield site within five mile s. While all three Bakersfield monitoring sites show higher annual average concentrati ons than other Valley monitoring sites, the Bakersfield-Planz site consistently measures the highest concentrations.

To investigate potential causes of the PM2.5 differences seen at Planz, the District evaluated emissions inventory data from co llected from permitted sources within a 5- mile radius of monitoring site. However, this analysis couldn’t capture non-permitted emissions activity (such as mobile sour ces), and the results were inconclusive.

The District and ARB also conducts speciation analysis to determine the types of particulates contributing to the Valley’s PM 2.5 concentrations. Accredited laboratories speciate many of the Valley’s collected PM 2.5 filters to quantify the amounts of up to 75 different chemical elements appearing on the filters. Though this analysis identifies

Appendix A: Analysis of Ambient Air Quality 

# DRAFT Appendix A- 

# 19

# Appendix A-20 

# DRAFT SJVAPCD PM2.5 Progress Report 

# individual atoms rather than co mplex molecules, these elem ental trends can point to potential emissions sources warranting further investigation. The speciation analysis identifies the Valley’s promi nent PM2.5 chemical constituents, including ammonium ions, nitrates, silicon, organic carbon, and el emental carbon. Through the California Regional Particulate Air Quality Study (CR PAQS, described in section 1.2 of this Progress Report) and the District’s own research efforts, additional speciation analysis is ongoing in preparation for the 2012 PM2.5 Attainment Plan for the 2006 PM2.5 NAAQS (mentioned in Section 4 of this Progress Report).