UNITED STATES ENVIRONMENTAL PROTECTION AGENCY

REGION IX 

75 Hawthorne Street 

San Francisco, CA 94105 

February 28, 2013

Mr. Daniel Inouye, Branch Chief

Monitoring and Planning

Air Quality Management Division

Washoe County Health District

P.O. Box 11130

Reno, NV 89520-0027

Dear Mr. Inouye:

Thank you for your submission of the Washoe County Health District, Air Quality Management 

Division’s 2012 Ambient Air Monitoring Network Plan in July 2012. Based on the information 

provided in the plan, EPA approves all portions of the network plan except those specifically 

identified below.

Annual network plans are important documents for regulatory purposes (e.g., State 

Implementation Plans, designations and redesignations) and public information, in addition to 

the myriad uses by the air districts. EPA is revising the review process for annual network plans 

to specifically check and document the comprehensive set of items that are required to be 

included in the annual network plans per 40 CFR 58.10 in a consistent manner. We have created 

a checklist that lists all these items and have included it as Attachment A. While the items in the 

checklist are required by EPA regulations, we acknowledge that we have not specifically 

requested some of this information in previous annual network plan reviews. We recognize that 

your plan may not have all the items that we have currently identified and hope to work with you 

on the inclusion of these items in future plans. To facilitate these changes, EPA has provided 

detailed feedback in the checklist where information should be included or revised in next year’s 

plan.

Please note that we cannot approve portions of the annual network plan for which the 

information in the plan is insufficient to judge whether the requirement has been met, or for 

which the information, as described, does not meet the requirements as specified in 40 CFR 

58.10 and the associated appendices. EPA Region 9 also cannot approve portions of the plan for 

which the EPA Administrator has approval authority. Accordingly, we are not acting on the 

specific portions of your agency’s annual network plan listed in Attachment B.

In addition to the checklist and list of specific plan elements where EPA Region 9 is not taking 

action, enclosed are additional detailed comments on the plan (Attachment C). All of the 

comments in Attachments A, B, and C should be addressed in next year’s network plan. If you 
have any questions regarding this letter or the enclosed comments, please feel free to contact me 

at (415) 972-3851 or Elfego Felix at (415) 947-4141.

Sincerely,

/s/

Matthew Lakin, Manager

Air Quality Analysis Office

Enclosures:

A. Annual Air Monitoring Network Plan Checklist

B. Elements where EPA is Not Taking Action

C. Additional Detailed Comments

cc: Julie Hunter, AQMD

Craig Petersen, AQMD

Kevin Dick, AQMD
Attachment B: Annual Air Monitoring Network Plan Items where EPA is Not Taking 

Action

We are not acting on the portions of annual network plans where either EPA Region 9 lacks the 

authority to approve specific items of the plan, or EPA has determined that a requirement is 

either not met or information in the plan is insufficient to judge whether the requirement has 

been met.

 Per 40 CFR 58.11(c), NCore and STN network design and changes are subject to 

approval of the EPA Administrator. Therefore, we are not acting on these items.

 EPA identified items in you agency’s annual network plan where a requirement was not 

being met or information in the plan was insufficient to judge whether the requirement 

was being met based on 40 CFR 58.10 and the associated appendices. Therefore, we are 

not acting on of the following items:

Item Checklist Row

(Attachment A)

Issue

For PM2.5, is at least one site 

in a population-oriented area 

of expected maximum 

concentration

77 Insufficient to judge

Instrument/monitoring method 

code for each monitor

54 Insufficient to judge

Monitoring objective for each 

instrument

58 Insufficient to judge

Instrument parameter code for 

each instrument

60 Insufficient to judge

Instrument parameter 

occurrence code for each 

instrument

61 Insufficient to judge

Distance from obstructions not 

on roof

91 Insufficient to judge

Additional information for each of these items is in included in Attachment A.
Attachment C: Additional Detailed Comments

 [Item 12] Please provide clarity and justification as to why no minimum Pb monitoring 

requirements currently exist for Washoe County (i.e. no current sources over 0.5 tons per 

year).

 [Item 47] Please clarify that distances between collocated monitors at Reno3 are 

acceptable given that flow rates are less than 200 liters/minute. Furthermore, the need for 

a PM10 collocation at Reno3 has been eliminated given that all instruments in AQMD’s 

fleet have been switched to continuous FEMs. Please clarify the flow rates for remaining 

collocated instruments.

 [Item 48] Please clarify in next year’s plan that AQMD no longer operates filter based 

PM10 SLAMS instruments and therefore no collocation requirement exists.

 [Item 57] Please rename the “Monitor Classification” rows in next year’s plan to read 

“Monitor Type.”

 [Item 59] Please rename the “Monitor Objective” rows in next year’s plan to read “Site 

type.”

 [Item 64] Please clarify in next year’s plan that AQMD now only operates continuous 

PM10 SLAMS instruments and therefore sampling frequency is continuous.

 [Items 67, 72, 73, 75, 79, 83] Please report minimum monitoring requirements in terms of 

active and required number of sites, rather than monitors. For example, a single site 

hosting multiple active monitors counts as a single site to meet minimum monitoring 

requirements.

 [Item 73] Recommend specifying on page 5 the CO monitor required at the NCore site.

 [Item 83] Although AQMD exceeds the minimum number of required sites for PM10, it 

would be helpful for next year’s plan to report the maximum concentrations in the 

network in order to support the minimum number of sites necessary.

 [Items 85 & 86] Please provide traffic counts for the nearest road to a monitoring site. In 

the case of the Incline site, the nearest road with available traffic counts appeared to be 

Tahoe Blvd. The Plumb-kit site road distance and count information was a bit unclear. 

Please more clearly pair a distance to the road with the traffic counts for that road. Traffic 

information reported for the Toll site suggests that PM monitors may be at a 

neighborhood scale, however these are currently labeled as middle scale. Please revisit 

and verify the spatial scale reported for PM monitoring at the Toll site.

 [Items 90] For future plans, as necessary, report any obstructions on the roof by providing 

a distance from the probe/inlet, as well as height of the obstruction.
 [General] EPA recommends that AQMD report detailed information for meteorology 

parameters on a per site basis and incorporate the details into the site tables found on 

pages 13-38. Examples of helpful detailed site information to provide include: instrument 

manufacturer and model, start date, siting, and QA/QC information, as applicable.