UNITED STATES ENVIRONMENTAL PROTECTION AGENCY

REGION IX

75 Hawthorne Street

San Francisco, CA 94105

November 1, 2010

Mr. Scott Nester

Planning Director

San Joaquin Valley Air Pollution Control District 

1990 E. Gettysburg Avenue

Fresno, CA 93726-0244

Dear Mr. Nester:

Thank you for your submission of San Joaquin Valley Unified Air Pollution Control 

District’s (SJVUAPCD) 2009 Ambient Air Monitoring Network Plan. We have reviewed the 

submitted document and have found that it meets the minimum requirements set forth under 40 

CFR Part 58.10. While this letter serves as official approval of the annual network plan, it does 

not constitute approval of the system modifications that are proposed in the plan for the future. 

We will continue to work with your district to review system changes as they proceed.

We also want to thank you for your timely submission of the SJVUAPCD’s 2010 

Monitoring Network Assessment Report, as required under 40 CFR Part 58.10. We recognize 

that preparing the network assessment was a significant project and we appreciate your effort. 

We plan on providing feedback to all agencies on network assessments during the winter 2011.

Enclosed, please find our comments on the plan. If you have any questions regarding this 

letter or the enclosed comments, please feel free to contact me at (415) 972-3851 or Kate Hoag at 

(415) 972-3970.

Sincerely,

/S/

Matthew Lakin, Manager

Air Quality Analysis Office

Air Division

Enclosure

cc: Jaime Contreas, SJVUAPCD
Comments on 2009 Data Year Network Plan for San Joaquin Valley Unified APCD 

Please update next year’s annual network plan to reflect the following comments:

1. Table 7 on Page 17 lists the PAMS sites in the SJV. In your next network plan, please 

confirm whether there was a Type 2 (maximum precursor emissions) site operating in the 

Bakersfield MSA during the 2010 ozone season.

2. Given the listed population and concentration of PM10 for the Merced MSA in Table 10 

(page 20), the required number of monitors should be 0-1, rather than 0. See 40 CFR Part 

58, Appendix D.

3. Non-FEM BAMs, SPMs, or other non-regulatory monitors should not be classified as 

SLAMS monitors nor counted toward meeting minimum monitoring requirements (Table 

10). See 40 CFR Part 58, Appendix D.

4. Please ensure that only FRM and FEM monitors with an objective of standards 

comparison are counted towards fulfilling the monitoring requirements in Table 10, as 

per 40 CFR Part 58, Appendix D. For example, the PM2.5 monitors in Clovis, Corcoran, 

Turlock and Tranquility, and the PM10 monitors in Bakersfield-Muni, Madera and Tracy 

appear to be needed to produce the total number of monitors in Table 10, but their 

objective is listed as “timely/public” only. 

5. Please ensure that the numbers of PM2.5 monitors are consistent between Tables 10 and 

11 for the Hanford/Corcoran and Madera MSAs.

6. Please clarify which samplers in Tables 11 and 12 are non-FEMs and which are FEMs.

7. Table 11 lists the Monitoring Objective as only “Timely/public” for the PM2.5 and PM10

FEM-BAMs and the PM10 TEOMs. If monitors designated as SLAMS are FRM/FEM 

monitor types and meet siting requirements, the data produced is considered comparable 

to the NAAQS. In a memo dated July 24, 2008, EPA has provided technical guidance on

implementing continuous PM2.5 FEM monitors as SLAMS. This memo stated that 

agencies can operate a continuous FEM particulate monitor alongside a filter-based FRM 

as an SPM for the purposes of evaluating the method for a trial period during which the 

data need not be included for design value calculations. The field evaluation period 

generally lasts 12 months, however, up to 24 months is allowed. Also, the primary filterbased FRM must remain operational at the site for the entire evaluation period. Any 

continuous FEM particulate SPMs that have operated longer than 24 months are 

comparable to the NAAQS. Please revise the Monitoring Objectives in Table 12 as 

necessary to reflect this. The memo described above can be found at: 

http://www.epa.gov/ttn/airs/airsaqs/memos/Use%20of%20PM2.5%20FEMS%20and%20

ARMs%20in%20SLAMS%20Network.pdf. 

8. Page 27 outlines the PM collocation requirements that apply to PQAOs. Table 11 on 

page 23 lists the PM10 FRM at Corcoran as being collocated, but the detailed site 

information tables in Appendix B for Corcoran and other monitors are unclear about what 

monitor pairs are collocated. Please specifically state which PM2.5 or PM10 sites in the 

SJVUAPCD are meeting a collocation requirement, and change the monitor type in 

Appendix B to “QA Collocated” rather than SLAMS.

9. The general process for soliciting public comments on the Annual Monitoring Network 

Plan is described on page 28. For future plans, please also submit the specific dates of 

the public comment period and specify whether or not any comments were received. See 

40 CFR Part 58.10
10. Pages 28 and 34 discuss that the district is evaluating discontinuing CO monitoring at the 

Fresno-Drummond, Fresno-Skypark and Turlock sites. Since EPA is currently reviewing 

the CO NAAQS, please consider as part of your evaluation that the CO monitoring 

requirements may change.

11. Page 30 states that there are no required monitors for SO2 to comply with Appendix D. 

In future network plans, please revise this section to reflect changed requirements due to 

the recent NAAQS revisions.

12. The discussion of approved PM10-2.5 monitoring methods for NCore on page 32 should be 

updated. See the website at http://www.epa.gov/ttnamti1/files/ambient/criteria/referenceequivalent-methods-list.pdf for information about approved PM10-2.5 reference and 

equivalent methods.

13. Page 34 states that with the addition of the Porterville and Manteca sites all monitoring 

requirements are met. Please clarify which pollutant requirements are being met by each 

site and when these sites will be operational.

14. Proposed Changes (pages 37-40)

a. When the District has completed its evaluation of all proposed changes, please 

submit any request with the appropriate documentation to EPA Region 9 for 

approval.

b. Please confirm whether or not the Bakersfield-Muni site, replacing the

Bakersfield-Golden site, will have the same monitors that were located at the 

Golden site.

c. The FEM-Bam at Tranquility is discussed on page 37 as an SPM for research 

purposes, not regulatory purposes. EPA allows for FEMs to be run on a test basis 

for 24 months. After that amount of time, the data from this monitor may be 

considered comparable to the NAAQS. See comment 7 above for details.

15. Monitoring Site Descriptions – Appendix A

a. Page A-3 discusses the temporary relocation of Hanford monitoring instruments 

to Corcoran. Please state in next year’s plan if the PM10 monitor was returned to 

Hanford or if it remains at Corcoran, and specify what time periods each 

instrument was operated at each location.

b. The Ash Mountain site description on page A-12 does not include the FRM 

PM2.5 monitor listed in Table 12 on page 26. Also, please clarify why the NPS 

PM2.5 FRM at Ash Mountain is not comparable to the NAAQS.

c. Page A-11: Please confirm whether SJVUAPCD or CARB operates the Visalia 

Church site.

16. Detailed Site Information – Appendix B

Some of the detailed site information tables are incomplete. For future network plans, 

please ensure that tables are completely filled out for every site. Also, please include all 

applicable information for each monitor and add the following information to the table 

for every monitor, as per 40 CFR Part 58:

a. Monitor type (SLAMS/SPM/QA Collocated etc.) for all monitors including NO2

and CO monitors.

b. List FRM/FEM/non-FEM and method code for particulate monitors. 

c. List POC for each monitor or indicate which monitor is the primary monitor for 

sites with more than one PM2.5 or PM10 monitor.

d. Will there by changes within the next 18 months? (Y/N)