MATIHEW H. MEAD STATE CAPITOL 

GOVERNOR THE STATE OF WYOMING CHEYENNE, WY 82002 

Office of the Governor 

January 12,2011 

Mr. James B. Martin, Regional Administrator 

US Environmental Protection Agency, Region 8 

1595 Wynkoop Street 

Denver, CO 80202-1129 

Dear Mr. Martin: 

In response to your letter regarding health-based National Ambient Air Quality Standards 

(NAAQS), the State of Wyoming is making recommendations on attainment or nonattainment 

classifications for the State of Wyoming for the I-hour primary standard for nitrogen dioxide 

(NOJ ) NAAQS that became effective on January 22, 2010. 

The State has used the most recent three years ofN02 monitoring data available to make 

attainment recommendations. The results and supporting data are found in Attachment 1 to this 

letter. The State used your letter dated November 9,2010 and 40 CFR 50 and Appendix S, the 

National Primary and Secondary Ambient Air Quality Standards for Oxides of Nitrogen (\vith 

nitrogen dioxide as the indicator) to determine appropriate boundaries for State designations. 

Based on this guidance, the State would like to designate the regions listed below as "attainment" 

for the current I-hour primary 'standard for nitrogen dioxide. 

Converse County 

Crook County 

Fremont County 

Attainment 

Attainment 

Attainment 

Attainment 

Attainment 

Attainment 

RECEIVED 

U.S. EPA Region 8 


RA'sOfflce 


JAN 1 4 2011 

PHONE: (307) 777-7434 FAX: (307) 632-3909 
Mr. James B. Martin 

January 20,2011 

Page 2 

Attainment 

Attainment 

Attainment 

Attainment 

Attainment 

Attainment 

Attainment 

Attainment 

Attainment 

Attainment 

Attainment 

Attainment 

Attainment 

Attainment 

Attainment 

Attainment 

The State went ahead and made "attainment" recommendations for all areas since the 

current monitoring network shows no violations and there are no requirements upon the State to 

deploy a new monitoring network to measure traffic impacts. 

There are portions ofthe above-mentioned counties which are under the jurisdiction of 

Tribal Authorities. It is our understanding that Tribal designations will be made separately from 

State designations. 

We look forward to your timely review and approval of this request. Ifyou have any 

questions concerning the details ofthis recommendation, please feel free to contact the State of 

Wyoming's Air Quality Division Administrator, Mr. Steven A. Dietrich, at 307-777-7391. 

Best regards, 

Governor 

cc: 	 John V. Corra, DEQ Director 

Steven A. Dietrich, AQD Administrator 

Christine Anderson, AQD 

Cara Keslar, AQD 

Chad Schlichtemeier, AQD 
........."tIOtlWQS 

AnnUIII PrImIIry o.ta CarnpIMeI_ 

MonIIiDr Name AQPSltaID Va, Y111ue(Ppbl (".,....._...... ---'*'I 

1IIuIIder8alln 56-005-0123 2007 1.8 88% 

2008 1.73 71% 

2009 1.68 83% 

South Campbell County 56-005-0456 2007 4.13 80% 

2008 3.07 85% 

2009 2.63 89% 

SOUdtPIIS 56-013-0099 2007 0.6 63% 

2008 0.48 72% 

2009 0.23 95% 

IIIouIcIIr 56-035-0099 2007 2.65 48% 

2008 1.79 68% 

2009 2.92 89% 

Daniel 56-035-0100 2007 0.27 99% 

I I 2008 0.12 98% 

2009 0.3 99% 

-

Wamsutter 56-037-0200 2007 6.61 90% 

2008 5.28 93% 

2009 5.19 85% 

I 

Murphy Ridge 56-041-0lO1 2007 1.73 98% 

2008 2.33 98% 

2009 1.85 95% 

Sites that do not meet the data completeness criteria as stated in CFR Part 50 3.1(b) 

An annual primary standard design value is valid when at least 75% of the data hours in the year are reported 

Note: The Annual Primary values have not been rounded to the nearest whole number as desCtibed In CfR Part 50 4.1(bJ 
I·Hour Primary NAAQS 

3-Y..,98 

MonIto,NII,.. ,.SIte ID PwcIntIIe 

.".,... (ppb) 

D"'COmp~ r.,__el of ........hours ... 

............­...... '-15" ............... - .... NAAQSI 

14 

Total Days =278 

12 

Total Days =323 

33 

Total Days =310 

38 

Total Days =360 

8 

Total Days =246 

10 

Total Days =285 

for the 

SUllst.tutlon test 

Tat Desiln V.lue 

V••, 98 Percentile 

ave,... (ppb) 
45 

40 

38 

19 

22 

13 

2 Data Source: EPA's AQS Data Completeness Report