Class I Area Impact Analysis for PSD Permit Application

Dwight Mallory Dwight Mallory to: 'john_notar@nps.gov' 08/02/2012 12:28 PM

Cc: Andrew Chew, Patrick Flynn

Mr. Notar,

In reference to the voice message exchanges we have had: I am 

contacting you in reference to a PSD permit application, submitted to 

U.S. EPA Region 9 on December 5. 2005, for the emergency flare at the 

McElmo Creek Unit Gas Compression Facility, located near Aneth, Utah. 

Resolute Natural Resources Company acquired the MCU facility from 

Exxon Mobil in 2006 and we have been working with Region 9’s 

permitting staff to obtain issuance of the PSD permit since that time.

You provided comments at the time the original PSD application and air 

modeling were submitted that no additional modeling for Class I 

impacts was necessary. However, since that time, EPA has promulgated 

new 1-hr NAAQS for NO2 and SO2, and requested that Resolute revise 

the modeling to account for the 1-hr NO2 and SO2 NAAQS. They also 

requested that Resolute contact you and allow the opportunity for you 

to review your comments in light of the 2010 revisions to the air 

emissions guidance for federal land managers. 

The emissions limits of 60 TPY S02; 73 TPY CO; 13.4 TPY NOx; and 95.4 

TPY VOCs applicable to the flare are unchanged since the original PSD 

application was submitted; and the flare’s actual emissions have 

decreased from the 29.2 tons S02; 66 tons CO; 12.1 tons NOx; and 90.6 

tons VOC reported by EOM for 2005 to 26.7 tons SO2; 45.4 tons CO; 

8.4 tons NOx; and 54.9 tons VOC for 2011. The SCREEN 3 model 

submitted with the PSD application estimated near-field impacts from 

the flare operating at 14.83 MMCFD for the entire year, or 7 times 

greater than the average rate for 2005. 

The results of the model showed that the flare did not cause or 

contribute to a violation of the National Ambient Air Quality Standards 

for NO2 or SO2 that were effective at the time of the PSD submittal. 

The revised SCREEN 3 model demonstrated that the flare did not to 

cause or contribute to a 1-hour NO2 NAAQS violation, but showed that 

the maximum 1-hr SO2 impact for the flare exceeded the interim SIL of 

3 ppb. At Region 9’s request, Resolute remodeled the SO2 emissions 

using EPA’s refined AEROMOD model and was able to effectively 

demonstrate that the flare does not cause or contribute to a 1-hour 

SO2 NAAQS violation.

I have attached Appendix D of the original PSD application, which 

includes the original communication between yourself and Justin 

Harrison at Exxon Mobil concerning impacts to Class I areas. Also 
attached is a map showing the location of the project in relation to

Class I areas. Please review and let me know if any additional 

information or modeling is necessary. 

If you would like to speak with EPA Region 9 staff, please contact 

Andrew Chew at (415) 947-4197. 

As requested by Region IX, I have also contacted Laura Romin with 

USFWS to allow an opportunity for USFWS to renew their comments 

regarding T&E species and critical habitat impacts. 

Dwight E. Mallory

Environmental, Health & Safety Coordinator

Resolute Energy Corporation

1675 Broadway, Suite 1950

Denver, CO 80202

Direct: 303-573-4886 X 1165

Cell: 970-302-8620

Email: dmallory@ResoluteEnergy.com

APP D from EOM PSD Ap.pdfMCU Class I Air.pdf




Canyonlands NP

Weminuche Wilderness

Mesa Verde NP

Weminuche Wilderness

 ̄

Resolute MCU Facility

50 Mile Buffer

Resolute Natural Resources LLC

MCU Class I Area Map

0 10 20 40 60

Miles

0 15 30 60

Kilometers