UNITED STATES ENVIRONMENTAL PROTECTION AGENCY REGION 8 1595 Wynkoop Street DENVER, CO 80202-1129 Phone 800-227-8917 http://www.epa.gov/region08

Ref: 8P-AR 

# DEC - 3 2009 David A. Finley, Administrator Air Quality Division Wyoming Dept. ofEnvironmental Quality 122 W. 25th Street Cheyenne, Wyoming 82002 Re: WyomingAmbientAirMonitoring Annual Network Plan, 2009

# <2.~-ldi~( Dear Mr.

### T'inlcy: Thank you for submitting the WyomingAmbient Air MonitoringAnnual Network Plan, .2009 under a cover lettcrdated September24, 2009. Region 8 has reviewed the network plan. This 

### letter and its enclosurc present ourcomments on the plan and document our approval. We appreciate the effort that the Air Quality Division put into the nctvvork plan, which included a section and an appendix to describe the proposed multi-pollutant NCorc monitoring station in Wyoming. The Divisionnamed this NCore station the Cheyenne

- Soccer Field site and gave it the AQS identification number 56-021-0100. Thc Office ofAir Quality Planning and Standards approved the NCore station in a letterdated October 30, 2009. Ifyou have any questions or commentsabout this letter, contactme at (303) 312-6434 or Joe Delwiche ofmy staffat (303) 312-6448.

Enclosure

cc: Cam KeslarENCLOSliRE COM!\JENTS ON WYOMING AMBIENT AIR MONITORING ANNUAL NETWORK PLAN,

### 2009 Thank you for modifying the tables to clarify the purposes ofmultiple air samplers or monitors at some stations. e.g.. samplers collocated for precision estimates orto accommodate sampling schedules. Please also considerrevising the terms used in the columns showingthe mcthods ofanalysis. The word ""gravimetric" can apply to gravimetric analysis using the reference methods for particulate sampling; however. its use in the tables can also apply to the TEOM method. It would be helpful to distinguish the manual methods from the continuous methods in this column. To further aid comprehension. please use currentphotographs ofthe stations wherever possible. The text describing the South Campbell County station (AQS identification number 

### 56-005-(456). for example. states that a PM10 TEOM analyzer was installed on November 5. 2008. but the photograph sho\\ls t\\lO high-volume PM 10 samplers on the roofofthe station. Thank you for including AQS identification numbers \vith the names ofthe air monitoring stations. In next year's network plan, pleasecorrect the AQS identification number ofthe air monitoring station at Jackson as it appears in appendix A from 56-039-0006 to 56-039­ 1006. The first paragraph ofsection 

### 3.1 on page 

### 30 states that the ten State and Local Air Monitoring Stations (SLAMS) for PMjo inWyoming include two types ofsamplcrs. These are the Thermo Partisol 

### 2000 and the high-volume PM 10 samplers. HO\vever. these add up to nine; the PM10 analyzeratthe Sheridan Police Department station (AQS identitication number 56-033­ 00(2) is the tenth ofthe PM 10 SLAMS. At this time this station is not required to have another**anal~izer** collocated for precision purposes according to 

### 48 CFR

### 58. Appendix 

### A. Please also correct orclarify the statements about the count ofspecial purpose monitors for ozone. The beginning ofsection 3.6 on page 34 refers to seven ozone monitoring stations that were operating in 

### 2008. butthe accompanying table summarizes ozone data colkcted at eight stations that year. As shown on page 

### 21 ofthe network plan. an additional ozone analyzer came on line at the Pinedale City Park/Pine Creek station in 

### 2009 (/\.QS identification number 56-035-0I0I). Thank you for submitting a netviork modification form to document the proposed site of the Cheyenne NCore station (56-021-0100). We encourage the Air Quality Div'ision to use these forms to document conditions at future proposed sites ofairmonitoring stations. includingland usc. sources orair pollution. and compliance with probe siting criteria. Region 8 has a goal of replying to network modification requests orally (orbye-mail) within five days and in writing within 

### 30 days.

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