1 Evan M. Shipp

2088 Lester Avenue

Fresno, CA 93720

Jessica Hafer San Joaquin Valley APCD 1990 E. Gettysburg Avenue Fresno, CA 93726

April 7, 2008

Subject: Comments on the Proposed 2008 PM2.5 Plan

Dear Jessie:

As in the past, thank you for the opportunity to submit comments on the proposed air quality plan. As you know, I have been involved in writing plans for some time, and I know how much work is involved. You and your colleagues should be commended fo r producing a plan that is based

on innovative science. There are sti ll some outstanding technical issues from my comments on the first and sec ond draft of this plan that could

affect the amount of reduction needed to achieve the NAAQS. Attached

are my comments.

Sincerely,

________________________ Evan M. Shipp2 Comments on 2008 PM2.5 Plan – Proposed (March 13, 2008) Evan M. Shipp (April 9 7 , 2008)

I have reviewed the Proposed San Joaquin Valley 2008 PM2.5 plan and have the following comments. First, I would like to thank the technical staff of the ARB and SJVAPCD. They have done a good job in providing documentation of most of the technical milestones in the plan.

In the recent past, I have commented extensively on the technical issues involved in the modeled attainment demonstration. For completenesss and

reference those comments are attached. Outstanding issues that were not addressed adequately in the District ’s response to comments in the new proposed plan include:

• Missing data when meteorological conditions were strong enough to cause exceedances of the NAAQS

• Failure to include intermediate year predictions of PM2.5 concentrations

• Failure to recognize alternative methods of analysis under the weight of evidence provisions of the EPA modeling guidelines

• Assessment of 2007 PM2.5 Data that shows numerous exceedances of the NAAQS have occurred and should be analyzed to protect near term public health

• Assessment of meteorological re presentativeness of the 2004-2006 period that sets the baseline desi gn value to determine whether worst weather conditions could produce more exceedances of the NAAQS in

the future

• Inclusion of EPA model guidan ce required photoch emical model

evaluations

• District contradiction of using mete orological indicators and then stating that they are invalid

• Poor documentation of the relative reduction factors, and lack of documentation on how the photochemical was used to derive these

These general comments are detailed below:

1. Missing Reference Method Data During Periods When Meteorology and Non-Reference Monitors Show High PM2.5 Concentrations

As stated in previous comments on the first and second draft of this plan, missing data during periods of weather stagnation that are conducive to high

PM2.5 levels should be considered when calculating the design value. This should be done under the weight of ev idence provisions of the PM2.5 modeling guidelines. Failure to address this issue will result in analyses that underestimate the amount and timing of reductions needed to achieve the NAAQS.3 As detailed in my comments on the s econd draft of the PM 2.5 plan, (attached) BAM and meteorology show that th ere is good evidence from weather

indicators that concentrations are much higher than characterized in the plan. Missing data during strong meteorol ogical events that provide PM2.5

concentrations have not been addressed in the plan. The District dismisses the correlation of PM2.5 to these weather para meters (stability index) as being poor; however, they use these indicators of meteorological pote ntial to produce PM2.5 forecast. In addition, as refere nced in the PM10 plan, the indicators were developed and presented by me in a peer-reviewed paper for AWMA (Shipp, 1995). The correlation of thes e stability parameters to PM2.5 and winter PM10 is about an r of 0.7, whic h is considered good for meteorology to air contaminant correlation. In addition, the SJVAPCD has provided numerous CRPAQS analyses that use these meteorol ogical indicators. Therefore, the District should apply these to assess the meteorological potential of the days where the data is missing and make ad justments to the design values. Again, this would be allowed under the weig ht of evidence provisions of the EPA guidelines. The District ow es it to the citizens of th e San Joaquin Valley to do a thorough job assessing the baseline con centrations to start the emissions reductions, and follow the letter and spirit of the law to protect public health, by analyzing the days with missing data that would be unhealthy.

2. Inclusion of Intermediate Year PM2.5 Predictions

To demonstrate reasonable further progress the plan needs to show that progress

toward attainment will be seen in PM 2.5 concentrations in the intermediate years before attainment. The plan only shows the attainment year concentrations. Since the plan indicate s that most emissions reductions occur close to the attainment year, the modeli ng needs to show steady progress toward

attainment.

3. Inclusion of 2007 PM2.5 Data

The District dismisses the comment made regarding the 2007 PM2.5 season data by saying that the data is not ava ilable yet. Because the real-time data indicates that numerous exceedances of the NAAQS occurred in 2007, every effort to include the data in the plan should be done. As an experienced air quality analyst, I have been able to have ARB expedite filter data when necessary. If the District cannot produ ce reference method data, they need to address fully why BAMS data is not incl uded. I have shown that the correlation of BAMS to FRM’s is very good and the analysis should be done under the weight of evidence provisions of the EP A modeling guidelines. The bottom line

is that the 2007 data shows that the SJV has levels well above the NAAQS, and

those emissions levels have not been br ought down sufficiently to protect public health. The design values need to be adjusted up by inclusion of the 2007 data.4 4. Assessing the Representativeness of the 2004-2006 Period

In accordance with EPA guidelines, and as outlined in my comments on the 2 nd
draft of this plan, the meteorology for the time period that the design value was

set needs to be assessed. My analysis for the 2 nd Draft of the plan indicates that meteorological potential for PM2.5, during the assessment years 2004-2006, was lower than in past years, and a re turn to worst case conditions, such as occurred in 1999-2002 would bring PM2.5 concentrations to well over the 24 hour and annual NAAQS. The response to comments that the District assessed 100 years of data without providing a ny documentation on that analysis is completely inadequate. Again, the District owes it to the citizen’s of the SJV to do a thorough job on insuring that emissions reductions on worst-case meteorological days will still bring th e valley into attainment of the 1997 NAAQS.

5. Inclusion of EPA Required Evaluation of the Photochemical Model

Since the proposed plan does not incl ude a full model photochemical model evaluation, it does not comply with EP A modeling guidelines and regulations.

The model evaluation is meant to asse ss the uncertainty of the photochemical modeling and can result in de signation of alternate cont rols strategies depending on that uncertainty. A full list of the photochemical model evaluation metrics is included in the plan, but there is no men tion of the specific model evaluation for the plan. Uncertainty assessment and discus sion is an integral part of specifying the amount and chemical species to control.

6. Documentation of the Relative Re duction Factors in the Plan and Demonstrating Reasonable Further Progress

The process used to calculate the RRF’s and show attainment of the NAAQS is

undocumented. It is unclear whethe r the RRF’s calculated from the photochemical model were the result of numerous runs at various percentage cuts in the inventory or just the 50% cuts as has been used in the past. Because photochemistry is non-linear, the RRF’s s hould be based on multiple cuts in the inventory. In addition, a run containing the attainment inventory should be documented. According to the ARB, th e District was give n RRF’s based on a future and base year model runs. Th is is not sufficient to demonstrate reasonable further progress toward attain ment. A majority of the emissions reductions in the plan occurs at the end attainment year, and therefore the modeling system using the base and e nd year inventory is not sufficient

The plan does not contain detailed docu mentation of the RRF’s that were used to scale the design values and show atta inment. The District answered this concern in the proposed plan by stating th at the files were too big to download

and distribute. It is the District’s and/or ARB’s res ponsibility to condense this information into an easily understandable format showing the output of the5 photochemical model before and after c ontrol for each chemical species and how that affects the design value. If multiple cuts are run, the District should include nitrate, sulfate, and VOC isopleths.

An evaluation of the result of control of individual NOx, VOC, EC, and SO2 needs to be performed. In addition, the District should show alternative species strategies and give more detail on the way the model was used to show that a NOx only strategy is viable. As in the comment above on analyzing intermediate years, the plan needs to provide documentation on speciated RRF’s and predicted species concentrations for intermediate years.

In addition to the more general comments above, I am providing specific comments (labeled S-number) on the text in the plan:

S-1. Page 3-2 Paragraph 1

The paragraph should state th at PM2.5 emissions could be retained in the SJV air basin for up to one month. Th is was seen in the 2000-2001 CRPAQS episodes, and it is relevant to the assessment of the representativeness of episodes. Long-term episodes are more diffi cult to control than short term ones. In addition, assessment of representa tive meteorology should include how long episodes last.

S-2. Page 3-2 Last Paragraph

The description of subsidence does not acc ount for the humidity increase at the surface as water vapor is trapped by the dry warm air above it. During major winter PM2.5 events, the descending ai r does not usually penetrate to the

surface and a subsidence inversion is formed.

S-3. Page 3-19 first paragraph in 3.3.3

The District determined that the annual standard is more stringent than the 24- hour NAAQS. This needs to be documented.

S-4. Page 3-19 second paragraph in 3.3.3

The statement in this paragraph supports the idea that the District does not have enough data to determine that the area is in compliance with the PM2.5 annual and 24 hour NAAQS. The plan states that the District is in compliance with the 24 – hour NAAQS.

S-5. Page 3-20 section 3.3.4

The paragraph states that the District will perform the SMAT analyses. ARB did perform these analyses.6 S-6. Page 3-22 Section 3.4 first paragraph

As stated above, without rigorous analys is and EPA approvals the text should

not state that some sites al ready comply with the NAAQS.

S-7. Page 3-23 Top

As stated in previous comments, the 2004-2006 period had missing data and better dispersive meteorol ogy and therefore is non-re presentative. Method 2 projections may be misleading.

S-8. Page 3-23 Regarding Lack of SMAT Documentation

The District and ARB sh ould provide detailed documentation on how the

SMAT calculations were derived from the photochemical model.

S-9. Page 3-27 Prior Accuracy of the PM10 Methodology

The District is only in a ttainment of the PM10 NAAQS due to flagging of data that is over the NAAQS by the Natural Ev ent Action Plans. These exceedances were not predicted by the PM10 plan.

S-10. Page 3-30 Air Monitoring and Trends

As stated above, the 2007 FRM data s hould be analyzed in the plan. My

comments on the 2 nd draft show that the 2007 data would change design values. ARB needs to expedite the processing of the 2007 FRM data and include it in the plan. It addition, the weight of evidence should include BAMS data which could be adjusted by the method portrayed in my comments on the 2 nd Draft of this plan.

S-11. Page 3-31 Weight of Evidence

The total attainment demonstration a pproaches using CMB and PMF are not independent checks because they still de pend on design value calculations that

are flawed.

S-12. Page 9-3 Last paragraph

As stated above, PM10 is dependent on NE AP’s and non-representative years of

2004-2006.

S-13. Page A-17 Because of the exceedances in 2007, the table should show 2005-2007 design

values.

S-14. Page A-2

Quarter completion problems should be i nvestigated. Is missing data due to aerosol loading during poor meteorological conditions?

S-15. Table A-3 and A-8

Missing data in 2004 at the highest sites du ring the highest quarters is shown in table A-3 and illustrates the point regardi ng the loss of high concentration data. Also, table A-8, shows the loss of data from 1999-2003 during the worst meteorological years.

S-16. Page A-14 through A-24 Trends Charts

As stated in previous comme nts, the trend charts need to reflect fluctuations in meteorology by using adjustment methods and/or analyzing meteorological parameters that correlate to PM2.5.

S-17. Page F-61 Regional Modeling

Here the protocol states that regiona l model evaluation will be included. As stated above, this evaluation is not included in the plan.

S-18. Figure H-4

Without a meteorological ev aluation, this chart is not definitive. The 2001 meteorology was much worst than it was in 2006. This may be the difference in the meteorological trend and not necessarily emissions.

S-19. Bottom of page H-8

Again, as stated above, these comp arisons with 1999-2001 and 2004-2006 need a meteorological evaluation.

S-20. Figure H-8

The upward trend in 1998-2001 is caused by strong meteorology that has not returned in the 2004-2006 pe riod the plan is based on.

S-21. Figure H-14 Speciated Trends

The species trends look pretty flat, and may not account for the entire PM2.5 trend. This should be explained.8 S-22. Page H-18

Again, the emissions trend looks pretty flat and would not account for the

reduction in PM2.5 seen between 2001-2005.

S-23. Page H-23

The PMF and CMB model corroborate, but th is is only a piece of the attainment process. More corroboration is need ed for other characteristics of the attainment demonstration. These might include other photochemical modeling, meteorological adjusted trends, and alternate design value calculations.

S-24. Figure H-23

These plots are useful for worst-case scenarios, but may not reflect the chemistry involved that produces high a nnual averages. More documentation is

needed on what data drives the annual average (e.g.-highest days, moderate episodes...).

S-25. Page H-27 top

As stated above, the 2005 design value may not be the best year to project into future years. This analysis is dependent on representative meteorology.

S-26. Page H-27 3 rd paragraph

It is not clear from this how the RRF ’s were derived (e.g. - photochemical model, rollback).

S-27. Page H-27 Bottom of page

As stated above, attainment is not the correct term. Only EPA can determine

that.

Appendix J Responses to my comments

Verbal Comments, February 25-26 Workshop

S-28. Comment 8

The District needs produce this analysis of 100 years of meteorological data. I am requesting that this be included in the plan.

S-29. Comment 169 This response does not address whether the District or A RB knows what types of days drive the annual standard and whether those were analyzed for NOx limitation. There is still a question as to whether moderate days that affect the annual average are NOx limited.

S-30. Comment 17

Under weight of evidence, alte rnate approaches can be used.

S-31. Comment 28

The new rule should consider meteorology and not forecasted AQI. As stated in previous comments, declaration of no bur n affects air quality to such a degree that forecasts do not verify.

S-32. Comment 31

This can be done under weight of evidence. The fact remains that missing data is occurring during stagnation periods wh en PM2.5 levels are high. Because of this phenomena, the District needs to fill in the missing gaps in the data.

Written Comments, December 18-19, Public Workshop

S-33. Comment 26

As stated above the missing data should be addressed. This is allowed under the weight of evidence. Also, stated above, the statement regarding the weak

correlation is incorrect.

S-34. Comment 28

As stated above, the 850mb temp – mi n temperature is used by the SJVAPCD, and has as good a correlation to PM2.5 as any met. parameter.

S-35. Comment 32

Response to comment noted that the plan is still missing the ARB model

evaluation.

S-36. Comment 34

The District is saying here that they have not shown documentation of the RRF derived from the photochemical model. In addition, as stated above, 2007 data

needs to be included.10 Verbal Comments, December 18-19, 2007

S-37. Comment 6

As stated above, ARB should expedite 2007 samples and get them into this plan.

S-38. Comment 11

Regarding the use of meteorological crit eria instead of forecasted AQI, response

to comment noted.

Written Comments, December 18-19, 2007 Public Workshop on the Draft

2008 Plan

S-39. Comment 21

Same as item 37. above.

S-40. Comment 32

Same as item 33, above.

S-41. Comment 33

2007 data needs to be included in the plan.

S-42. Comment 35

The District cannot make the statement that levels are not as high with the recent 2007 stagnation unless they have a me teorological analysis to prove that. Please include an analysis showing the stagnation events do not have as high a concentration as in the past. This an alysis should include both strength and

duration of these events.

S-43. Comment 36

It appears that the District did do a long-range trend an alysis using dichot data.

S-44. Comment 44

Neither the 24-hour nor the annual NAAQS address the issue of the month long episodes the SJV experiences.11 Evan M. Shipp Comments on SJVAPCD 2008 PM2.5 Plan, 2 nd Draft, February 14, 2008

I have reviewed the 2008 PM2.5 Plan 2 nd draft and have the following

comments. I would like to commend the technical staff’s of the SJVAPCD and ARB for the good job they have done docum enting the work that has been done so far. Since I have written parts of ma ny air quality plans, I know this can be a daunting task.

Overall, I find the plan much more comp lete and documented than that of the first draft; and many modeling and tec hnical issues I have raised in my

comments on the first draft have been addr essed. However, there are still some remaining issues, and I have provided more detail below on my previous

concerns than on the 1 st Draft of this plan. Some of these issues may affect the amount of control needed to achieve the NAAQS. The plan in respect to modeling does not meet all EPA guidelines. Most of the issues below should be addressed to meet the weight of ev idence sections of the EPA modeling guidelines. The main outstand ing and unresolved issues are:

• Recalculate design values accounting fo r missing federal reference filter data during events when meteor ology and real-time data show exceedances of the PM2.5 NAAQS

• Recalculate the design value using 2 007 data, and show how the District would attain the NAAQS using data for 2005-2007

• Reassess the 2004-2006 period for repr esentative meteorology, average meteorological parameters that correl ate to PM2.5 show that the period had less pollution potential than p re vious periods.

• Provide, as required by EPA and addr essed in the District’s protocol

, a full photochemical model evaluation

• Document whether the NOx limita tion on PM2.5 is verified by the photochemical model for all days

• As a corroborative attainment te st, use the EPA method of applying Relative Reduction Factors (RRF) w ith direct photochemical model

output

Below are details of the bulleted concerns and additional comments:

Design Value Recalculations

Under EPA’s weight of evidence requirem ents, the District should reassess the 24-hour and annual design values in the plan due to missing data when meteorological conditions are conducive to high PM buildup. EPA’s method of data substitution may not fully account for this biased loss of data during periods when BAMS concentrations are high. The design value for some sites, and especially the highest concentration s ite, Bakersfield-California is affected by missing data when meteorologica l conditions are conducive to PM2.512 formation. Although, the data is missing, correlation to pa rallel real-time monitors is good, and this data can be used to calculate alternate design values.

I have attached corr elation plots and data in attachment 1.

I have long suspected that when concen trations are high, flow controllers or other instrument compon ents malfunction on the reference method samplers

, invalidating samples that would be high enough to affect design values. Analysis of the data supports this hypothesis. In years where meteorology produced high concentrations of PM2.5, f ilter based reference method data, is missing when BAMS data are high. For ex ample, viewing a sort of BakersfieldCA, shows, that at Bakersfield-CA, a s ite with daily filter FRM data, in 2005,

the 1 st , 2 nd ,5 th ,6 th , 7 th , 10 th , highest BAM values had no corresponding FRM’s (table 1). In addition, in 2003 the th ree highest BAM concentrations are missing reference data for those dates (t able 2). Highest data in 2004 and 2006 are not missing in Bakersfield, but BAMS concentrations for those years are relatively moderate and it would not be expected that the instruments would have filter loading problems.

Table 1 Sorted by BAMS Concentrations-2005 Missing FRM Data at

Bakersfield - CA

Date BAMS Real-time

Data 24-Hour

Concentration Filter Reference

Method

24-Hour

Concentration 12/11/2005 104.1 missing 12/13/2005 98.5 missing

11/23/2005 88.1 79.7

12/9/2005 86.9 missing 12/10/2005 86.5 missing 12/12/2005 83.6 missing

12/14/2005 83.5 80.5

11/24/2005 82.7 85.7

12/15/2005 81.7 80.1

12/8/2005 76.2 missing

11/22/2005 73.2 73

10/23/2005 71.4 58.5

3/10/2005 68.4 54.7

10/22/2005 68.3 55.5

10/21/2005 68.3 53.7 11/21/2005 68.3 missing13 Table 2 Sorted by BAMS Concentrations 2003 Missing FRM at

Bakersfield-CA

Date AvgOfBakersfield5558 California

Avenue 5558

CALIFORNIA AVE,

BAKERSFIELD 7/4/2003 86.4 missing 12/5/2003 71.6 missing 11/20/2003 69.9 missing

12/6/2003 68.7 55.5

1/4/2003 68.0 53.2

12/4/2003 66.5 53.9

12/18/2003 64.0 54.3

1/31/2003 61.1 44.7

1/8/2003 60.6 43.5

1/6/2003 59.9 40

1/15/2003 58.8 42.6

11/6/2003 58.2 46.1

1/3/2003 57.9 46.4

1/30/2003 57.5 41.5 11/30/2003 57.4 missing

In 2005, the highest BAMS concentrati on at Bakersfield-CA was 104 ug/m3. My correlation analysis s hows that at Bakersfield, BAMS are about 15% higher than FRM’s, so this might correspond to about 88 ug/m3 on the FRM’s which is well over the 65 ug/m3 with the health e ffects and mortality associated with

such concentrations. EPA has indicated to me that this type of non-reference method analysis would be allowed under the weight of evid ence provisions of the modeling and attainment test guidance. In addition, BAMS applications for Federal Equivalent Method have been submitted to EPA, the application shows

that BAMS at Bakersfield – CA are ve ry linear with correlation and slopes within EPA specifications ( www.nescaum.org/documents/mac/mac-committeemeeting-1/ bam -1020-2x- fem -gobeli.pdf) . The SJVAPCD may indicate that the BAMS are not run in the same fashion, maintained similarly; however, in a weight of evidence analysis, these issues are not relevant, and the data should stand on its own, with the correlation show n in attachment 1 of these comments. Therefore, I am requesting th at the APCD calculate BAMS

- derived design values with possibility of applying correc tion factors to the data for differences

in measurement methods.

Because of the missing FRM’s, the 98% design values remain below the NAAQS; however, a look at the BAM’s, even adjusted for differences in measurement, would indicate that the Di strict is over th e NAAQS. A straight 98% for Bakersfield-CA shows that concentrations for 2002, 2003, 2004, 2005 and 2006, would be 71, 61, 64, 82, and 62 respec tively. In addition, a review of BAMS data for 2007 at Bakersfield - CA, shows a 98% of 76. Scaling these for

the correlation to the reference method and averaging them will still reveal concentrations greater than the 24-hour NAAQS. Contra ry to the response to14 my comment pertaining to this in the pla n, the District should assure that using

this alternative method to calculate the design value, controls would reduce this level to under the NAAQS.

Because of this missing data, an analysis of how this affects the annual average also needs to be done. Preliminarily, the BAMS at Bakersfield – CA for 2007 shows an average of 19.4, much highe r than the reported 2004-2006 period. A

look at the 2007 data is needed before the weight of evidence analysis is complete. Not only should the District look at the BAMS, but should also expedient the processing of the filter (FRM’s) for 2007. The District needs to

show that with these new data attainment can be reached by the attainment date.

In addition, the District’s analysis is asse rting that the District already meets the PM2.5 24 hour NAAQS, but given the severe air quality episodes that occurred in 2005 and again in 2007, the District s hould rethink this strategy. Foremost the District should not apply for attainme nt status until the most recent filter reference method data is analyzed. Furt hermore, I am very concerned that the District will be granted attainment stat us, and use the Nature Event Action Plan to nullify any future exceedances of the PM2.5 NAAQS from consideration of

future controls. Real-time instrume nts during 2004-2007 have caught numerous violations of the NAAQS, and the District owes it to the health and wellbeing of the residents of the San Joaquin Valley to mitigate this health risk.15 Assess the Meteorologica l Representativeness of the 2004-2006 Design

Value Period

EPA modeling guidance provides for an assessment of the meteorological representativeness of the design value period (2004-2006). As stated in several meetings, and reiterated in my comment s on this plan and the previous PM10 plan, the 2004-2006 period shows that mete orology, especially meteorology for the annual average, is less conducive to PM2.5 formation than previous years. In fact, that period shows the lowest annual average for stability factors conducive to PM formation during the time that official PM2.5 concentrations have been measured (1999-2007). As th e District meteorologists know, and as the originator of the stability factor used in the plans, the average stability

correlated to PM2.5 was less in the last few years than in other years. The

District also contends that the correlation of PM2.5 to this factor is not high, but

statistics show that the correlation or for the correlation is around 0.7; which is about as good as these factors get for co rrelation to meteorology. That is based on my experience with meteorological fact ors I have formulated for ozone and

PM in Central and Southern California. Figure 1 shows an average value by year for this factor. It is apparent on the chart that the 2004-2006 had less stability on average than other years. In addition, in my comments on the PM10

and 1 st Draft of the PM2.5, I have provided more documentation on this subject. Responses to these comments were not adequate, and I am requesting a full investigation of this subj ect and a re-evaluation of how this affects the design value and control strategy.16 Figure 1

October 01-January 31 Average T850 Stability Bakersfield

-2 -1 0 1 2 3 4 51999-20002000-20012001-20022002-20032003-20042004-20052005-20062006-2007* Average T850 Stability

As Required By EPA Include a Full Photochemical Model Evaluation

As stated in my verbal comments on the plan, the EPA requires a full model evaluation of the photochemical model. This evaluation has full bearing on the uncertainty of the estimation of reduc tion needed to achieve the NAAQS, and

the conservatism of that estimate. Acco rding to ARB, this evaluation will be forthcoming, and needs to be included a nd then analyzed in the next version of the plan. Hopefully, this model evalua tion will include analysis of individual chemical species and total PM. Once the model is evaluated, then the uncertainty of the application can be quan tified. This evaluation is relevant to

whether the model can be used to a ssess such issues as NOx, NH3, and VOC

limitation.

Document whether the NOx limitation on PM2.5 is verified by the photochemical model for all days

Since this plan is mainly based on annual average calculations and the photochemical model was run for a full year, there should be some assessment on the daily change in NOx limitation in the plan. I believe that the NOx limitation statements made in the plan are based on severe episodes and those do not necessarily drive the magnitude of the annual standard. The plan should17 include an assessment of the individual days in the modeling effort and whether some days show major sensitivity to VOC and/or ammonia control. If these days exist, perform an analysis on the ir re contribution to the annual average.

Use Direct Photochemical Model Output to Calculate RRF’s

As required by the EPA and included in the District’s own protocol, direct output of the photochemical model should be used to provide an alternative RRF. From discussions with ARB, direct RRF’s from the annual CMAQ modeling are available for many chemical species including nitrate, sulfate, elemental and organic carbon. These should be analyzed as an alternative to the rollback method. The protocol included in the plan describes independent modeling analysis using straight RRF’s as a check on the rollback modeling for use demonstrating attainment of th e NAAQS. In EPA guidelines, they recommend using the output of the phot ochemical model straight to scale the DV by the RRF. Since the protocol a nd EPA guidelines recommend the use of straight photochemically derived RRF’s, the District should at least show these

calculations as an alternative.18 Attachment 1

Bakersfield -CA PM2.5 FRM and BAMS Concentrations

y = 0.8558x - 2.1204

R 2 = 0.9081

-20

0 20 40 60 80 100 120

0 20 40 60 80 100 120 140

BAMS concentration ug/m3FRM concentrations ug/m3

Fresno-1st PM2.5 FRM and BAMS Concentrations

y = 0.9193x - 2.9268

R 2 = 0.9015

-20

0 20 40 60 80 100

0 10 20 30 40 50 60 70 80 90 100

BAMS Concentration (ug/m3)FRM Concentrations (ug/m3)19 Evan M. Shipp

2088 Lester Avenue
Fresno, CA 93720

Jessica Hafer San Joaquin Valley APCD 1990 E. Gettysburg Avenue
Fresno, CA 93726

January 8, 2008

Subject: Comments on the Draft SJVAPCD Draft 2008 PM2.5

Dear Jessie:

Thank you for the opportunity to submit comments on the subject air quality plan. My comments pertain to the modeling and data analysis portion of this plan. Many of these comments I made verbally in the workshop in December. These comments have also been distributed widely to stakehol ders. Attached are my comments.

Sincerely,

Evan M. Shipp20 

### Evan M. Shipp, Comments Regarding the San Joaquin Valley Air Pollution Control District

2008 PM2.5 Plan and PM2.5 Modeling Protocol

Acknowledgements

First, I would like to thank the techni cal staff of the SJVAPCD and ARB that has done an excellent job documenting the analysis that has been performed, so far, by both agencies. The meteorological analysis section in appendix E has addressed some of my earl ier questions regarding repr esentativeness of recent PM2.5 data. I would especially like to thank the staff that provided the modeling protocol, which has detailed the steps toward modeling attainment in

the SJV. I would also like to tha nk the San Joaquin Valley Technical and Policy committees for designing the field programs and providing the data that this plan is based upon.

Summary and General Comments

Attainment of the 65 ug/m3 PM2.5 NAAQS is a major health issue in the San Joaquin Valley in that concentrations a bove that standard, as documented in numerous papers and journals, result in major illnesses and premature death.

These health effects have been documen ted by EPA as justification for the new 35 ug/m3 PM2.5 NAAQS. Therefore, the plan should be rigorous, meet, and exceed the guidelines set down by EPA for this less stringent 65 ug/m3 NAAQS.

Because there are many components lacking in the plan, this first effort on the PM2.5 plan should not be considered a dr aft, but only a working draft. As stated in the protocol, crucial to demonstr ating attainment is the use of state of the art photochemical modeling and app lication of that model’s relative

reduction factors. Because this has not been done, the PM2.5 plan is incomplete. I had originally outlined my concerns regarding the modeling analysis to Scott Nester, SJVAPCD, a nd John DaMassa in an e-mail sent on August 30, 2007 (attached). Concerns over the meteorology were also documented in my comments to the SJVAPCD on the PM10 Attainment Plan dated August 10, 2007 (attached ). The bullets below summarize my concerns with the Draft 2008 PM2.5 Air Quality Plan as written by the SJVAPCD.21 • As stated in the plan, the modeling is incomplete, the analyses lack several required elements including the current regional photochemical modeling and a rigorous wei ght of evidence approach

• Because of the lack of current pho tochemical modeling, the amount of reduction needed to achieve the NAAQS is in flux, and the plan cannot be thoroughly evaluated

• Since the plan lacks current photoc hemical modeling, there is no model evaluation as specified in the SJ V protocol (appe ndix F) and EPA guidelines

• Although numerous exceedances of the 65 ug/m3 24-Hour PM2.5 NAAQS have occurred during the last five years, the plan dismisses these and does not adequately address that NAAQS

• The plan does not address meteor ological representativeness; the protocol states that this analysis wi ll be done; the years the plan is based on (2004-2006) have had better meteorology than past years

• In accordance with EPA guidelines, and repeated in the SJVAPCD protocol on page F-61, curre nt regional modeling is required and is the mainstay of the demonstration of atta inment, this analysis has not been performed in a manner conforming to the guidelines

• As stated in the SJVAPCD protocol and EPA guidance, although some analysis has been performed the plan does not adequately address trends, and more importantly meteorologicall y adjusted trends for the 24 – hour NAAQS

• As specified in EPA guidelines, th e plan should address unmonitored peaks, but this has not been done because there is no current photochemical modeling

• The plan does not adequately addres s the effect of controlling for the annual standard on the 24- hour NAAQS

• Even though the plan states that atta inment statistics show that the SJV

is near attainment for the 24 – H our NAAQS, recent real-time (Fall, 2007) data show that meteorologica l can still drive PM2.5 well over the 24 hour NAAQS and adversely affect public health

• The plan should address the length of PM2.5 episodes in the SJV and their effect on public health

• The District should change the re sidential wood combustion rule to make it more effective by using meteorological criteria rather than

forecasted PM2.5 concentrations

Detailed Comments

Overall, I have major concerns that the plan in its present state does not address many of the requirements set down by EPA. Much of the information required by EPA modeling guidelines is missing a nd is referenced in the plan as forthcoming. Due to this lack of detail, the plan can only be considered preliminary and not a draft

.2223 Address the 24 – Hour PM2.5 NAAQS

I have major concerns regarding, the failu re of the plan to adequately address the 24-hour PM2.5 NAAQS. Although the Distri ct claims that it is attainment for that health standard, the SJVAPCD has not been officially designated by

EPA that it is in attainment for the 65 ug/m3 NAAQS, nor has the District proven that major multi-day weather stagnation events will not cause more NAAQS violations. Attaini ng the 65 ug/m3 PM2.5 standard is literally vital to the health of persons living in the San Joaquin Valley. Health studies indicate that acute levels above this NAAQS cause premature death, and failure to attain this NAAQS will result in excess morta lity among the population of the SanJoaquin Valley. Because exceedances of the 24- hour NAAQS occur in multiday episodes, San Joaquin Valley, resident s respiratory systems are insulted day after day. Many peer-reviewed papers supporting this view are available and many are referenced in the support docu ments for the new 35 ug/m3 NAAQS. The plan should address the health impacts of contiguous multi-day NAAQS exceedance episodes.

Use More Rigorous Weight of Evidence

According to EPA, attainment of the PM2.5 NAAQS (24 hour NAAQS) is more than just modeling and analyzing the last three years of PM2.5 data. It is a rigorous process of corroborating the modeling system in cluding analyzing meteorology for representative or typical conditions. As specified in the EPA modeling guidelines, areas with PM2.5 24-hour design values concentrations between 62-67 ug/m3 need to provide a weight of evidence approach to determining attainment. For the last 3 y ears, design values in this range have

been recorded in the SJV. Because the District has not done a complete analysis of predicting the future 24 – hour design value the determina tion as to whether weight of evidence is needed cannot be made.

Weight of evidence using rigorous trends and data analysis for both the 24 –

hour and annual standard needs to be a ddressed in the plan. Although the plan

stated that there is not en ough data to do trends analys es, fine particulate data does exist back many years, and this analys is needs to be incorporated into the plan. There is enough data at the Fresno-1 st Street site to l ook at trends for several years of nitrate and carbon da ta. In addition, several years of IMPROVE data at the national parks above the valley can give an idea of what is being transported from the SJV into the parks. Any tr end analyses should

also address the issue of missing data. During the early 2000’s, data was lost during meteorological conditions that were conducive to forming high

concentrations of PM2.5.

The District and/or ARB should also do meteorologically adjusted trends analyses to determine whether there is statistical significance to the better PM2.5 values of recent years. More el aboration is needed on the claim that24 recent strong stability events have resulted in lower PM2.5 concentrations. These analysis should include a look at the 24 – hour average trend, and whether historically strong poor dispersi on events would still cause exceedances of the 24-hour NAAQS.

In addition, complete metrics of PM2.5 tre nds need to be included in the plan. There is a great deal of variati on in measuring improvement of PM2.5 concentrations depending on what trend sta tistics is selected. At the least, the District should provide me teorologically adjusted aver ages for both annual and

winter PM2.5 season and the number of exceedances of the 24-hour NAAQS per year. Because the exceedances are a key factor in the health effects seen in the SJV, the later statistic should be provided even though the design value is below the NAAQS. Because of the statis tical nature of the 98% design value, many exceedances can occur that effect public health even when the District

demonstrates attainment.

The plan only provides corroboration of modeling using another source apportionment model (PMF). There is no co rroboration of the attainment test. As stated above, the attainment test involves photochemical modeled relative reduction factors (RRF), and other statis tical analyses. The plan rebuffs EPA methodology of using RRF and photochemica lly modeled chemical species to

test for attainment. This EPA a pproved methodology should be used and compared to the plan’s methodology for corroboration.

Although there is some analys is in the plan, the Distri ct has not done a rigorous study of meteorology to determine whether the cleaner concentrations in recent years have been due to weather. Preliminary analyses indicate that meteorological parameters that are co rrelated to PM2.5 have shown less PM2.5 forming potential in the last three years than in previous periods. The plan should look at the strength and duration of historical episodes. Specifically, as indicated in my written public comments of August 10, 2007 (attached) on the PM10 Maintenance Plan and Request for Re designation, I believe that if periods of stagnation occur for as long as th e period in the CRPAQS episodes of 2001,

PM2.5 concentrations would exceed th e NAAQS with such frequency as to affect the PM2.5 design values. Furtherm ore, the SJVAPCD protocol states that when design values, are between, 62-67 ug/ m3 as occurs in the SJV, the weight of evidence analysis is crucial. This should warrant a more rigorous analysis of the weight of evidence than included in the plan as specified by the protocol. This issue is also addressed below by the paragraph regarding recent exceedances of the NAAQS. The Distict should do this analysis and submit to EPA for redesignation before they claim to be in attainment of the 24-hour NAAQS.

The Plan Should Analyze the Most Recent Data25 Although the SJVAPCD claims they are in attainment of the 24-hour NAAQS, analysis of recent PM2.5 episodes that occurred in November and December 2007, indicate that poor meteorology can still drive PM2.5 well over the NAAQS. Recent BAMS real-time PM2.5 measurements show that for the period from 11/2/2007 through 11/ 8/2007, 11/15/2007 through 11/16/2007, 11/28/2007 through 11/29/2007, and 12/12/ 2007 through 12/16/2007 there were numerous exceedances of the 24 hour NAAQS. Preliminary ARB and

SJVAPCD data shows that real-time inst ruments recorded the following number of violations of the 65 ug/m3 NAAQS so far this season. The District needs to do a very rigorous analysis of these recent events to determine the cause and the emissions control implications for these episodes. Of note was the episode that

occurred outside of the traditional PM2.5 season, usually starting in midNovember, in early November. The cause of this unusual event needs to be determined. The number of exceedances of the PM2.5 65 ug/m3 this PM2.5 season are provide below.

Site Number of Exceedances

2007-08 PM2.5 Season to Date

Bakersfield-Calif 9

Bakersfield-Gold 7

Clovis 9

Corcoran 4

Fresno-First 8

Modesto-14th 1

Turlock 1
Visalia, Church 4

The maximum 24 hour average measured during these events was 92 ug/m3 or almost 1.5 times the 24- hour NAAQS. In Bakersfield, there was a PM2.5 event that lasted 7 days. Since levels grea ter than 65 ug/m3 are considered unhealthy for everyone, this has tremendous hea lth effects on the general population.

The District has historica lly claimed that these are not official exceedances because BAMS are only an equivalent monitoring method; however, the District’s own analysis shows that the correlation between the BAMS and Federal Reference Monitors is very good and within the measurement error of

each monitor. Because the correlatio n between the BAMS and FRM’s is high, the District should investigate and incl ude in the plan episodes where BAMS remain high and above the NAAQS. Once available, the District should also analyze the recent preliminary data fro m the filter based FRM’s before making attainment claims. I am very concer ned that the District will attempt to designate itself attainment for th e 24 – hour PM2.5 NAAQS, and once in

official attainment use the Natural Even ts Action Plan (NEAP) to exempt any future violations of the NAAQS from c onsideration of control. That policy

which was used for PM10 is detrimental to health of the citizens of the SJV.26 Analyze the Effects of the Annual St rategy on 24-Hour Concentrations

In addition, the SJVAPCD has not analy zed the effects of the annual PM2.5 control strategy on the shorter-term 24- hour concentrations. As described in EPA’s modeling guidelines, there may be c ontrol strategies th at reduce ambient controls on an annual basis, but may have little effect, no eff ect, or exacerbate episodic PM2.5 problems. Also, at issue is whether chemical speciation used for the annual assessment is representati ve of the species involved in the 24- hour standard problem. The guidelines describe the recommended procedure

for the modeled attainment test. This procedure also addresses non-monitored peaks using interpolation and RRFs. Th e software is called MATS (modeled attainment test software).27 Change the Residential Wood Combustion Forecast Criteria

Finally, although the District has excelle nt forecasting staff, the current residential wood combustion rule by usi ng forecasted concentration criteria has

made it less effective than if had been ba sed strictly on meteorological criteria. Because the declaration of a prohibited day many times results in reduction of concentrations levels below the 65 ug/m3, forecasters are reluctant to forecast greater or equal to that 65 ug/m3 NAAQS. The criteria results in difficulty for the forecasters, where if they call the prohibited when conditions are near theNAAQS they will be under-predicting the NAAQS violation, and overpredicting if they do not call the proh ibited. This reluctance to call the prohibited is driven by public scrutiny of the forecast. Instead, to protect public health, the prohibited should be based on meteorological crit eria that would cause an exceedance of the NAAQS if residential wood combustion were allowed. The prohibited declaration is th e largest single action the District can take to protect the NAAQS and public health.28 Attachement 1 E-Mail to Scott Nester and John DaMassa Send August 30, 2007, Regarding Concerns on PM2.5 Modeling

As promised in phone conversations to bot h of you at the end of last week, I am documenting my concerns regarding the modeling for the PM2.5 attainment plan. To summarize, I am concerned th at the modeling for the plan should follow, as closely as possible, the late st EPA guidelines, and that the protocol for the modeling be done in time for public review. EPA guidelines follow an approach of using speciated relative reduction factors (RRF). The reason for my concern is that the latest PM10 pl an relies on procedures that were customized for SJVAPCD, essentially speciated rollback, and somewhat difficult to follow. For PM2.5, any devi ation from the EPA guidelines needs to be well justified. In some instances, there may be SJV specific issues that will require modifying EPA procedures, but this should only be done with a detailed justification for the change . Because of the extreme technical nature of the protocol, a review period of 30 days s hould be provided. In my reading of the modeling guidelines, EPA require s the following key elements:

• A modeling protocol for public review that describes the procedures and

models used to demonstrate attainment

• Evaluation of the period used to calculate the design value for meteorological representativeness

• Application of speciated RRF derived from an EPA approved photochemical model (e.g.-CAMx, CMAQ, UAM-V)

• Application of primary Gau ssian modeling to apply RRF

• Use of a variety of modeling episode s, and a full year of modeling for the annual NAAQS

• Use of EPA approved meteorologi cal models (MM5, WRF, RAMS)

• Adjustments for retained NO3, SO4, OC, EC mass

• Elimination of doubled counting for use of combination of photochemical and Gaussian models.

In my conversions with ARB, it appears th at there is not a plan to use Gaussian or dispersion models for investigating hots pots. If this procedure not used, there should be some very good documentation on why PM2.5 hotspots were not

addressed.29 Justification for the calculation of the de sign value, and the procedure used to deal with missing data needs to be incl uded in the plan. Th is procedure should consider that in the early years of PM2.5 monitoring instrument problems caused deletion of data during weather conditions that produced very high PM2.5 values. Data substitution that ignores this fact should not be used. One way to deal with this would be to co nstruct data based on the correlation of meteorology to PM2.5. Because of the natu re of that correlation analysis, the

reconstruction of data would be biased low, but would be better than not including data for those PM2.5 values wh ere we know the data was very high. A very rigorous analysis of the periods where data deletion occurred needs to be performed.

As I have stated in comments on the PM 10 plan, in general, the meteorological representativeness of the last 3 years of meteor ology compared to historical episodes needs to be analyzed for both the strength and duration of PM2.5 episodes.

EPA guidelines call for correction of speciated mass to account for sampling

characteristics of these chemicals and allow for comparison of the sum of the species to the total PM2.5 concentration on RFM filters. The procedure outlined by EPA, for this should be followed.

The District and/or ARB should perform speciated trends, and if possible

correct those for meteorol ogy. If correlation between PM2.5 chemical species and meteorology are found, those corrected trends can give an indication of

what source sectors have been influenced by control strategies. Before I left the District, I had looked at wh at species we available in the EPA’s AQS system,

but most of the data was from IM PROVE sites in remote locations. Preliminarily, it did not look like key species from these sites had declined as fast as the design values. A much more rigorous look at thos e trends needs to

be done.

These are my concerns for now, but I am sure as we get further into the SIP process, I will have more comments. I appreciate the chance to get these comments in before the PM2.5 process is more solidified. Since new evidence

shows even more links of PM2.5 to mortal ity, it is imperative that this SIP be

done with most scientifica lly creditable evidence.

I appreciate the chance to comment on th e PM2.5 plan in the early stages of development.

If you have questions regarding my co mments, please call me at (559) 903-2290

or e-mail me at troutshp@comcast.net

.30 Attachment 2 Comments on PM10 Plan Including Analysis of the Meteorological Representativeness of Recent Particulat e Episodes Sent to David Nunes on

8/10/2007

Evan M. Shipp

2088 Lester Avenue
Fresno, CA 93720

David Nunes Atmospheric Modeler 1990 E. Gettysburg Avenue
Fresno, CA 93726

August 10, 2007

Subject: Comments on the Draft PM10 Maintenance Plan and Request for Redesignation

Dear David:

Thank you for the opportunity to submit co mments on the subject plan. Attached are those comments. My statements pertain to subjects within my pr edominate expertise; however, given more time, I would provide other comments regarding modeling.

Sincerely,

Evan M. Shipp31 

### Comments on the PM10 Maintenance Plan and Attainment Designation

Evan M. Shipp

2088 E. Lester Avenue Fresno, CA 93720 troutshp@comcast.net (559) 903-2290

As stated at the August 8, 2007, workshop regarding the PM10 maintenance plan, I am providing written commen ts detailing my concerns on the meteorological and modeling analyses for the plan. Aside from those technical comments, as I and others stated at the meeting, the timeline for submitting these comments was unreasonably short and should not be repeated for future plans. Considering the complicated tec hnical issues involved in these plans, a comment period of 30 days would be much more appropriate. In additional, I am very concerned that the analysis w ill set a precedent for the PM2.5 plans. Due do the very serious health consequen ces of PM2.5 the analyses for that plan need to be much more rigorous than this document, and use state of the science methods for both the modeling and atta inment demonstration. Specific

technical comments follow:

1. The plan states that guidelines and regulations for the PM10 maintenance plans require a demons tration that meteorology was not unusual during the period that was used for the attainment

demonstration. As I stated at the me eting, the District showed that the average meteorology for 2004-2006 has some of lowest potential for forming PM10 than in recent history; therefore, without further analyses the period of time the attainment d eclaration is based on the plan does not pass the EPA test. More detail ed work on how representative the meteorology has been during the past three years needs to be done. I

would as least recommend that the Dist rict look at the persistence of the meteorological factors during the 20 04-2006 and compare that to other periods. Several CRPAQS and IMS95 reports have indicated that the duration of an episode from weathe r system cleanout to the next cleanout has a significant eff ect on the magnitude of PM10 concentrations. As an expert in this type of analysis, I originated the use of this analysis in 1995 in an AWMA paper, my review of that period compared to historical records indi cates that both average stability and episodic stability during the 2004-20 06 period were less conducive to forming PM10 than many previous pe riods. I have attached plots of stability for the 2004-2006 for Fresno, and for comparison show years where the stability parameter rema ined high for a long period. In reviewing plots since the 1970’s it appear s that occurrences of persistent stability of much more magnitude than the 2004-2006 years have occurred with some frequency The Di strict needs to review these plots32 and determine the representativeness of the last 3 years. The plots below show stable periods in the 1999-2000 and 2000-2001 winter seasons that are much stronger and persistent than the 2003-2004 and 2005-2006 winter period. Also, note that data is missing at Fres no – First Street sites because instruments malfunctioned during high aerosol loading. This may be driving the change th e District sees in the correlation between the stability parameter and PM2.5 in recent years. In addition, there are three plots, showing the 2004-2006 winter PM seasons. Note that due to trough and frontal weathe r systems the atmosphere was less conducive to PM formation during 2003-2004 and 2005-2006 seasons. 2004-2005 winter does show some persis tent strong stability, but not quite the strength and duration of other poor dispersion years. The stability parameter does not stay as hi gh or persist as it did during other years. This is especially true of 2006. The District has diurnal stability plots dating back to the 1970’s a nd these should be analyzed for comparison with the 2004-2006 period. For historical purpose, I have included the 1989-1990 winter stability plot that shows poor dispersion conditions for nearly one month. In an episode like this, even at today’s emission levels, PM10 could be driv en over the NAAQS for many days

in a row.33Fresno-1stPM2.5VRS. T850MB Stability01020304050607080 11/15/99 11/22/99 11/29/99 12/6/99 12/13/99 12/20/99 12/27/99 1/3/00 1/10/00 1/17/00 1/24/00 1/31/00 2/7/00 2/14/00 2/21/00 2/28/00

Fresno 1 st PM 2.5 (micrograms / m 3 )-15.0-10.0-5.00.05.010.015.0 Oak. T 850 MB Stability ParameterPM2.5T850MB Stability Parameter34Fresno-1stPM2.5VRS. T850MB Stability01020304050607080 11/15/00 11/22/00 11/29/00 12/6/00 12/13/00 12/20/00 12/27/00 1/3/01 1/10/01 1/17/01 1/24/01 1/31/01 2/7/01 2/14/01 2/21/01 2/28/01

Fresno 1 st PM 2.5 (micrograms / m 3 )-15.0-10.0-5.00.05.010.015.0 Oak. T 850 MB Stability ParameterPM2.5T850MB Stability Parameter35Fresno-1stPM2.5VRS. T850MB Stability01020304050607080 11/15/03 11/22/03 11/29/03 12/6/03 12/13/03 12/20/03 12/27/03 1/3/04 1/10/04 1/17/04 1/24/04 1/31/04 2/7/04 2/14/04 2/21/04 2/28/04

Fresno 1 st PM 2.5 (micrograms / m 3 )-15.0-10.0-5.00.05.010.015.0 Oak. T 850 MB Stability ParameterPM2.5T850MB Stability Parameter36Fresno-1stPM2.5VRS. T850MB Stability01020304050607080 11/15/05 11/22/05 11/29/05 12/6/05 12/13/05 12/20/05 12/27/05 1/3/06 1/10/06 1/17/06 1/24/06 1/31/06 2/7/06 2/14/06 2/21/06 2/28/06

Fresno 1 st PM 2.5 (micrograms / m 3 )-15.0-10.0-5.00.05.010.015.0 Oak. T 850 MB Stability ParameterPM2.5T850MB Stability Parameter37October 1, 1989-February 28, 1990 Stability Parameter and Precipitation-10-5051015 11/15/89 11/22/89 11/29/89 12/6/89 12/13/89 12/20/89 12/27/89 1/3/90 1/10/90 1/17/90 1/24/90 1/31/90 2/7/90 2/14/90 2/21/90 2/28/90020406080100120PPTT850 Stability Parameter3839 2. PM10 Trends

As stated by several meeting participants, th e Figure 2 graphic needs to be caveated by indicating the amount of PM10 exceedances or the NAAQS that have been removed from the analyses, but were flagged under the Natura l Events Action Plan (NEAP’s). A list of pending and approved NEAP’s should be included in the plan. In addition, as stated at the meeting, a look at the trends in individual chemical species needs to be done to assess the control program.

3. PM10 Hotspots

The District needs to ensure that no non-m onitored PM10 hotspots occur or will occur in

the District due to local sources. This is true of both directly emitted PM10 and secondary PM10 from ammonia or NOx sources. Placement of locally high NOx sources may result in increased PM10 from ammonium nitrate.

4. Chemical Speciation Trends

The District needs to look at chemical spec iation to determine whether controls, such as,

the residential wood combustion rule have been effective, and that secondary PM concentrations are declining. Preliminary analysis that I ha ve done is not conclusive. A graphic of trends follows for Fresno-First St reet and shows little improvement for EC and

nitrate.

5. Future modeling endeavors

Although, the speciated rollback, my be adequate for this plan, in the future for PM2.5 modeling, speciated Relative Reduction F actors are specified in the EPA PM2.5 guidelines. This will require regional modeling of nitrate, sulfate, EC, and OC, to use in the RRF calculations. The PM2.5 plan should follow all modeling guidelines, including the required corroborativ e analysis. This is a complex pr ocess, and needs to be done with public and stakeholder scrutiny. The first step to this process is the EPA required modeling protocol that needs to have a significant review pe riod for comments of at least 30 days.