UNITED STATES ENVIRONMENTAL PROTECTION AGENCY

REGION IX
75 Hawthorne Street San Francisco, CA 94105

February 28, 2013

Mr. Mike Sword, Engineering Manager Clark County Department of Air Quality 4701 W. Russell Road, Suite 200 Las Vegas, Nevada 89118

Dear Mr. S word :

Thank you for your submission of the Clark County Department of Air Quality ’s (DAQ) Annual Network Plan Report in June 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 spe cifically 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. W hile 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 cu rrently 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 not e that we cannot approve portions of th e 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 co mments 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 youhave 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

Enclosure s : A. Annual Air Monitoring Network Plan Checklist

B. Elements where EPA is Not Taking Action

C. Additional Detailed Comments

cc: Yousaf Hameed, DAQ Tina Gingras, DAQAttachment B : Annual Air Monitoring Network P lan I tems where EPA is N ot Taking

Action

We are not acting on the portions of annual network plan s 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.

 NCore and the plan for NO 2 monitoring require EPA Administrator approval . Per 40 CFR 58.11(c), NCore is subject to approval of the EPA Administrator and per 40 CFR 58.10(a)(5) plans for establishing NO 2 monitoring sites are submitted to the EPA

Administrator for action. Therefore, we are not acting on these items.

 System modifications (e.g., site closures or moves) are subject to approval per 40 CFR 58.14(c). Information provided in the plan was insufficient for EPA to approve the following system modifications listed in the plan per the applicable requirement :

o Relocation or shut down of the Walter Johnson and/or Green Valley sites t o bring into 40 CFR 58, Appendi x E compliance (Options 3

- 4, page 13)

o Termination of CO monitoring at J.D. Smith, Orr, and Winterwood sites (page 54)

o Termination of Jean site (page 54)

o Termination of additional sites (page 54)

Therefore, we are not taking action on these items as part of this year’s annual network plan.

 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

Identification of maximum

concentration ozone monitor(s) 68 Insufficient information to judge

Distance from trees 92 Insufficient information to judge in some instances, not meeting requirement in some

instances Distance from supporting

structure 89 Insufficient information to judge in some instances, not meeting requirement in one

instance

Obstructions not on roof 91 Insufficient information to judge

Dates of last two semi

- annual

flow rate audits for Pb 45 Insufficient information to judgemonitors

Frequency of one

- point flow

rate verification for Pb samplers audit. 41 Insufficient information to judge

Operating schedule for each

monitor 26 Insufficient information to judge in some

instances Monitoring objective for each

instrument 58 Insufficient information to judge

Obstructions on roof 90 Insufficient information to judge

Additional information for each of these items is in included in Attachment A

.Attachment C : Additional Detailed Comments

 [Item 13] Although EPA Region 9 is not taking action on the NO 2 portions of the plans this year, for next year, please identify sites fulfilling the NO 2 area

- wide and RA40 requirements.

 [Item 23] The Paul Meyer (p.33) and Walter Johnson (p.36) AQS site IDs list an incorrect county code that should be corrected to 003 rather than 002. EPA suggests that DAQ report the AQS site ID for Winterwood (p.37) formatted as XX

- XXX

- XXXX

rather than XX

- XXXX

- XXX. SPM using FRM, FEM, or ARM methods are required to report to AQS site IDs in the network plan.

 [Item 25] Sampling and analysis methods are discussed in various sections of DAQs plan. EPA recommends that DAQ consolidate the reporting of sampling and analysis methods into the detailed site description tables found on pages 22

- 37. The sampling and anal ysis method should be reported on an individual instrument by instrument basis. For FEM and FRM instruments, reporting the method code fulfills this requirement. Please also ensure to report the sampling and analysis method for Pb, NOy, and any new monitor ing that may be reported in next year’s plan.

 [Item 35] EPA recommends that DAQ incorporate a public review process for changes to

the PM2.5 network even in the case when a lease is lost or notice to vacate is received.

 [Item s 43 & 44] Although most of the Annual Performance Evaluations for gaseous, and

semi

- annual flow rate audits for PM instruments were reported, EPA found a few instances where the information was missing. An ozone evaluation at Jerome Mack and

an NO 2 evaluation at Joel Neal were not f ound for 2011. Each of the PM 10 sites at Palo Verde, Boulder City, and Jerome Mack only reported one flow audit for 2011, and similarly for continuous PM 2.5 at Jerome Mack, only one flow audit was reported. Please report all required annual performance eva luations and semi

- annual flow are audits in next year’s plan. If an evaluations or audit did not occur in a particular year, please provide this clarification in the network plan.

 [Item 56] Please report start dates for seasonal (Apex, Mesquite) monitors in the annual network plan.

 [Item 57] Currently DAQ has monitor type listed as “Type” in the detailed site section of the network plan (p.22

- 37). This “Type” should be relabeled to read m onitor type and should be reported for each instrument at each of th e sites, rather than on a per site basis. There is an inconsistency for the PM2.5 continuous sites that are also listed as SPMs in p.18 since a monitor type cannot be both an SPM and a SLAMS.

 [Item 59] Site types are found throughout the plan labeled as “ Objective” and “Monitor Objective Type.” Please change these to read site type. [Items 60 & 61] Although most parameter and parameter occurrence codes are reported

on page 19, a few were not found. Those not found include: Pb and PM 10

- 2.5 at Jerome Mack, seasonal ozone at Apex and Mesquite. Please report parameter and parameter occurrence codes for all instruments in next year’s plan.

 [Item63] For PM 2.5 please clarify the season in which monitoring takes place. EPA recommends that sampling frequency and season information gets incorporated into the detailed site tables of pages 22

- 37.

 [Items 67, 72, 74, 75, 79, 83] Although EPA recognizes that DAQ in all cases meets or exceeds all minimum monitoring requirements, please include the representative area (e.g. MSA, CBSA) population when describing m inimum monitoring requirements.

 [Items 85 & 86] Please report the distance and traffic counts for the neare st roads from the Apex and Mesquite sites. It is recommended that a credible traffic count from the nearest road is reported for all sites.

 [General] Although not required, EPA recommends that for s pecial stud ies where

monitor ing has occurred in at least two consecutive years, such as the Spring Mountain Youth Camp site

, DAQ consider including the following additional information (as applicable) in the annual monitoring network plan that will allow for a better understanding of the studies conducted:

o AQS Site Identification

o Location: street address and geographic coordinates

o Sampling and analysis method

o Operation schedule: sampling frequency and season

o Scale of representativeness

o Start date

o Instrument monitor type, monitoring objective, and site type

o Param eter code

o Parameter occurrence code

 [General] EPA recommends that DAQ report detailed information for meteorology parameters on a per site basis and incorporate the details into the site tables found on pages 22

- 37. Examples of helpful detailed site infor mation to provide include: instrument manufacturer and model, start date, siting, and QA/QC information, as applicable.