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Chew, Andrew

From: Dwight Mallory [Dmallory@resoluteenergy.com]

Sent: Wednesday, February 06, 2013 4:05 PM

To: Chew, Andrew

Subject: RE: McElmo Creek Main Flare PSD Permit Application: Visibility Impact/Soils and Vegitation 

Analyses

Attachments: McElmo Creek Main Flare Level II VISCREEN Modeling_013013.pdf

Categories: McElmo Creek PSD

Andrew,

In consultation with Don Shepherd at NPS, Tom Hormel at McVehil Monnett Associates conducted a Level 1 and Level 2

visibility screening analysis for potential impacts from the McElmo Main Flare at Hovenweep National Monument.

Hovenweep National Monument is the only identified federal Class II area within 50 km of the Main Flare. A copy of the

report from that analysis is attached for inclusion in the additional impact analysis for the Main Flare PSD.

I conducted a map search and a review of websites and literature for the area to determine if there were potentially

sensitive non‐federal parks, forests, monuments, or recreational areas within 50 km of the project. Included in the

search were websites of the Utah Division of State Parks; Navajo Nation Parks and Recreation; Colorado Division of Parks

and Wildlife; and New Mexico Division of State Parks.

The only potential Class II areas discovered were 1) The Edge of The Cedars State Park, located 48 km northwest of the

project; and 2) The 4‐Corners Monument Navajo Tribal Park, located 32 km southeast of the project. A separate visibility

screening analysis of these units was not conducted because the distance to each of these units is greater than the

distance to the 2  Hovenweep units that are most distant from the project. The modeling conducted for the Hovenweep

analysis showed no perceptible plume impacts would occur at the 2 more distant Hovenweep units during any time of

day. In addition to their distance from the project, neither the Edge of The Cedars State Park nor the 4‐Corners

Monument Tribal Park have a high potential for visibility impairment since they consist largely of man‐made structures

rather than terrain features.  

http://navajonationparks.org/  

http://stateparks.utah.gov/  

As for the soil and vegetation impact analysis, I have asked Mr. Hormel to take a look at the depositional impacts

analysis that was included in Section 7.4.3. of the PSD permit application and see if he can supplement the write up as

needed. I should have something from Tom by the 20th of this month.

Let me know if you need anything in the meantime.

Thanks.

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

From: Chew.Andrew@epamail.epa.gov [mailto:Chew.Andrew@epamail.epa.gov] 

Sent: Wednesday, January 30, 2013 4:01 PM 
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To: Dwight Mallory 

Subject: McElmo Creek Main Flare PSD Permit Application: Visibility Impact/Soils and Vegitation Analyses 

Dwight, 

Per our phone conversation, as our office is wrapping things up in preparation for public notice, here are 2 more topics we 

hope Tom can help make our write-up more robust: 

 Visibility Impact Analysis

The visibility impact analysis for fulfilling the additional impacts analysis requirement pertains to visibility impairment (e.g., 

plume blight) in Class II areas. My understanding from Don Shepard is that Hovenweep is the only Class II federal area 

within 50 km of the Main Flare. The analysis should include Class II areas described below. 

The Class II visibility impacts analysis is independent of the Class I visibility Air Quality Related Values. Please confirm 

whether there are other Class II federal and state areas (e.g., potentially sensitive parks, forests, monuments, and 

recreational areas) within 50 km of the project. (If there is not a specifically designated "Class II area(s)", the project 

should consider a location(s) where there may be some potential for visibility impairment. For instance, if there is an area 

where there are terrain features that provide a contrast that makes changes in visibility perceptible, that area may be 

considered.) 

Please discuss the potential visual impacts of the project on these areas. Information presented in the EPA 1992 

workbook should be considered - 

 U.S. EPA (U.S. Environmental Protection Agency), 1992. “Workbook for Plume Visual Impact Screening and Analysis.” 

EPA-450/R-92-023. October.

http://tinyurl.com/EPA1992plume 

Then based upon the evaluation, conduct a VISCREEN Level 1 analysis (beyond what already was provided for Class I 

areas) for any identified areas. If necessary, conduct a Level 2 analysis if the Level 1 impacts are exceeded. If there is a 

valid reason not to conduct an analysis, please provide that narrative. 

 Soils and Vegetation Analysis

Please characterize the potential impacts to soils and vegetation in consideration of the following suggested additional 

references to help make the write-up more robust: 

 U.S. EPA (U.S. Environmental Protection Agency), 1980. “A Screening Procedure for the Impacts of Air Pollution Sources 

on Plants, Soils, and Animals. Final Report” EPA-450/2-81-078. December.

http://tinyurl.com/EPA1980Soils 

Web Soil Survey (WSS) for the National Cooperative Soil Survey via the USDA Natural Resources Conservation Service. 

http://websoilsurvey.nrcs.usda.gov/app/HomePage.htm From site: 

Web Soil Survey (WSS) provides soil data and information produced by the National Cooperative Soil Survey. 

It is operated by the USDA Natural Resources Conservation Service (NRCS) and provides access to the largest 

natural resource information system in the world. NRCS has soil maps and data available online for more than 

95 percent of the nation’s counties and anticipates having 100 percent in the near future. The site is updated and 

maintained online as the single authoritative source of soil survey information. 

Links to recent EPA Region 9 Fact Sheets that include discussions about soils and vegetation, as examples of what we 

have proposed in our permits, are as follows: 
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 Pio Pico, Item IV.2 - http://www.regulations.gov/#!documentDetail;D=EPA-R09-OAR-2011-0978-0005 

 Palmdale - http://www.regulations.gov/#!documentDetail;D=EPA-R09-OAR-2011-0560-0004 

 SPI Anderson - http://www.regulations.gov/#!documentDetail;D=EPA-R09-OAR-2012-0634-0003

Please let me know if you have further questions. Thank you. 

- Andrew 

 ------------------------------------------- 

Andrew Chew, P.E. 

T: (415) 947-4197 | F: (415) 947-3579 | chew.andrew@epa.gov

U.S. EPA, Region 9, Air Permits Office (AIR-3) | 75 Hawthorne St., San Francisco, CA 94105