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 UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
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REGION 8
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1595 Wynkoop Street
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Denver, CO   80202-1129
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Phone 800-227-8917
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		www.epa.gov/region8




Ref: 8ARD-PM
				
Thomas H. Gibbons						
HES Professional				
MPLX
1515 Arapahoe Street, Tower 1, Suite 1600
Denver, Colorado  80202
	
Re: 	MPLX, LP, Chapita, Wonsits Valley and Coyote Wash Compressor Station Minor Modifications to Operating Permits

Dear Mr. Gibbons:

This letter is regarding the minor permit modifications to the initial 40 CFR part 71 operating permits (Part 71 permits), permit numbers:

      Chapita Compressor Station, V-UO-000012-2018.01
      Wonsits Valley Compressor Station, V-UO-000005-2018.00
      Coyote Wash Compressor Station, V-UO-000015-2018.00
      
On July 23, 2021, the U.S. Environmental Protection Agency, Department of Justice and MPLX, LP agreed to modify the terms of surviving Paragraph 23 of a Consent Decree (United States v. Questar Gas 
Management Co., Case No. 2:09-CV-00167-TS-PMV) to effect the following change: MPLX may use Test Method 320 of 40 CFR part 63, appendix A (Method 320) in lieu of Method 7E of 40 CFR part 60 (Method 7E) and Method 10 of 40 CFR part 60 (Method 10) for the measurement of nitrogen oxides and carbon monoxide, respectively, at its facilities (i.e., Chapita Compressor Station, Coyote Wash Compressor Station and Wonsits Valley Compressor Station). 

Therefore, we are concurrently issuing the revised Title V permits to accurately describe and permit the correct engine test methods approved at the Chapita Compressor Station, Coyote Wash Compressor Station and Wonsits Valley Compressor Station. We also modified Wonsits Valley Compressor Station and Coyote Wash Compressor Station to show the ability to submit reports via the Compliance and Emissions Data Reporting Interface (CEDRI). We have determined that the modifications can be classified as a minor permit modification in accordance with 40 CFR 71.7(e)(1) and have revised the Title V permits accordingly. Permit amendments and revisions are not subject to public participation requirements.

The modified operating permits and all other supporting documents are accessible for your review at https://www.epa.gov/caa-permitting/caa-permits-issued-epa-region-8 or in their respective dockets at https://www.regulations.gov: 



      Chapita Compressor Station, EPA-R08-OAR-2018-0346 
      Wonsits Valley Compressor Station, EPA-R08-OAR-2018-0349
      Coyote Wash Compressor Station, EPA-R08-OAR-2019-0196

The modified Title V permits are being issued with the following permit numbers:

      Chapita Compressor Station, V-UO-000012-2018.02
      Wonsits Valley Compressor Station, V-UO-000005-2018.01
      Coyote Wash Compressor Station, V-UO-000015-2018.01

Please note that these modified Title V permit issuances will not change the originally issued permit expiration dates. 

If you have any questions concerning the final modified permits, please contact Colin Schwartz, of my staff, at (303) 312-6043 or at schwartz.colin@epa.gov.   

                                    Sincerely,
                                          
							Carl Daly
                                    Acting Director
							Air and Radiation Division
							

cc:	Mike Natchees, Director, Air Quality Program, Ute Indian Tribe

