Document 6bXQdJpJ78qNEOgz1jqwaJ6Vo

EPA Inspection Report - Page 1 of 34 Region 6 - Enforcement & Compliance Assurance Division INSPECTION REPORT Inspection Date: Media Program: Regulatory Program(s) 08/02/2023 Air CAA, TX SIP Company Name: Facility Name: Facility Physical Location: (city, state, zip code) Mailing address: (city, state, zip code) County/Parish: Facility Phone Number Facility Contact: DFW Midstream, LLC Dalworthington Gardens Gathering Station No. 1 3018 W. Pioneer Parkway Dalworthington Gardens, Texas 76016 910 Louisiana Street, Suite 4200 Houston, Texas 77002 Tarrant County (832) 930-6524 Jerry Castillo Director of Regulatory Compliance Jerry.castillo@summitmidstream.com FRS Number: Identification/Permit Number: Media Identifier Number: NAICS: SIC: N/A TCEQ Regulated Entity Number ("RN") RN105828891 Air Permit No. 91291 & 166168 ICIS-AIR TX0000004843901770 211111 N/A Personnel participating in inspection: Uma Lad EPA R6 Benjamin Donaldson EPA R6 Aimee Boss EPA R6 Jerry Castillo Summit/DFW Midstream Jarrod Stewart Summit/DFW Midstream Physical Scientist Environmental Engineer Physical Scientist Director of Regulatory Affairs Operations Manager EPA Lead Inspector Signature/Date Supervisor Signature/Date UMA LAD Digitally signed by UMA LAD Date: 2023.09.28 08:46:30 -05'00' Uma Lad Digitally signed by DARRIN DARRIN LARSON LARSON Date: 2023.09.28 11:07:51 -05'00' Darrin Larson Date Date 6ENFORM-019-R8.2 (02/12/2020) 1 EPA Inspection Report - Page 2 of 34 DFW Midstream, LLC / Dalworthington Gardens Gathering Station No. 1 Inspection Date 08/02/2023 Section I - INTRODUCTION PURPOSE OF THE INSPECTION EPA Region 6 inspector, Aimee Boss, and inspectors-in-training, Ben Donaldson and I, Uma Lad ("We," "Us"), arrived at Dalworthington Gardens Gathering Station No. 1 ("DWG"), located at 3018 West Pioneer Parkway, Dalworthington Gardens, Texas, 76016 at 8:30 AM on August 2, 2023, for an announced inspection. The facility is owned and operated by DFW Midstream, LLC ("DFW"), a subsidiary of Summit Midstream Partners, LP ("Summit"). We met with Summit/DFW representatives Mr. Jerry Castillo, Director of Regulatory Affairs, and Mr. Jarrod Stewart, Operations Manager. Aimee Boss presented her credentials to Mr. Castillo and Mr. Stewart, and I informed them that this was an EPA inspection to determine compliance with the facility's permits and the Clean Air Act ("CAA"). The scope of the inspection was a partial compliance evaluation ("PCE") and includes evaluation of the compliance with facility permits, the Texas State Implementation Plan ("SIP"), and federal CAA regulations. The facility currently operates under the Permit by Rule ("PBR") for Oil and Gas Facilities No. 91291 and the Non-Rule Standard Permit ("NRSP") Pollution Control Project ("PCP") No 166168. The Texas Commission on Environmental Quality ("TCEQ") was notified but did not participate in the inspection. The sign-in sheet for the opening conference is included as Appendix 3. FACILITY DESCRIPTION Natural gas enters the DWG facility through gathering lines and into a two-phase separator. Liquid from the separator is transferred to produced water storage vessels, while gas is routed to the compressors. Following compression, gas undergoes dehydration by passing through a triethylene glycol ("TEG") contactor. Dry gas from the dehydration process is routed offsite via a sales pipeline. Rich TEG from the contactor is sent to a reboiler for separation. Lean glycol from the reboiler is sent back to the TEG dehydrator, while vapors from the reboiler are routed to a condenser and then a combustor for destruction. Vapors from the produced water storage vessels are controlled by a combustor too. Produced water is transferred off-site by trucks. Section II - OBSERVATIONS We began a facility walk-through with Mr. Stewart and Mr. Castillo at 8:50 AM. We examined the facility with a Forward Looking Infrared ("FLIR") optical gas imaging ("OGI") camera. Mr. Stewart stated that Summit/DFW personnel are at DWG daily to conduct maintenance for 2 to 3 hours. Summit/DFW shuts down the facility annually for certain operations and maintenance work. Separator Natural gas enters the facility through 16-inch and 20-inch gathering lines and into a two-phase separator. Liquid from the separator is routed to three (3) produced water tanks, while gas is routed to the compressors. 2 EPA Inspection Report - Page 3 of 34 DFW Midstream, LLC / Dalworthington Gardens Gathering Station No. 1 Inspection Date 08/02/2023 Compressors Following separation, gas is routed to two (2), 2500 horsepower ("hp") electric motor driven reciprocating compressors ("D-100" and "D-200," see Photo 1 in Appendix 1) and a 6000 hp electric motor driven reciprocating compressor ("D-300," see Photo 8 in Appendix 1). At the time of the inspection, only the D-100 compressor was operating. Mr. Stewart explained that regular maintenance of the engines includes replacing and rebuilding valves, which are based on shooting valve caps with a temperature gun daily. We examined the compressors with the FLIR camera and observed emissions and heat from the D-100 compressor (see MOV_0035 in Appendix 2, Area of Concern ("AOC") #1). Mr. Stewart explained that the observed emissions were from a variable volume pocket. DWG also operates a 400 hp electric compressor ("D-400," see Photo 7 in Appendix 1), which provides gas compression for a well pad located offsite for another company. We examined the compressor with the FLIR camera and did not observe any emissions. On August 14, 2023, Summit/DFW provided compressor and engine design specifications that show that the D-100 and D-200 compressors were manufactured in 2008 and have operated at the 2500 hp rating since 2010. The facility's permits indicate that the compressor engines are not affected sources under the New Source Performance Standards ("NSPS") Part 60, Subparts IIII, JJJJ, the National Emission Standards for Hazardous Air Pollutants ("NESHAP") Part 63, Subpart ZZZZ, and 30 Texas Administrative Code ("TAC") 106.512. TEG Dehydration and Regeneration Following compression, gas passes through a TEG contactor to remove water from gas, and the dry gas from this process is transferred offsite via the sales line. Rich glycol from the TEG contactor undergoes separation at the glycol reboiler (see Photo 4 in Appendix 1). From the glycol reboiler, lean glycol is sent back to the TEG dehydrator, while vapors containing benzene, toluene, ethylbenzene, and xylene ("BTEX") pass through a condenser ("BTEX eliminator") and then a combustor ("BTEX combustor") for destruction. We observed emissions with the FLIR camera from the exhaust stack on the glycol reboiler (see MOV_0034 in Appendix 2, AOC #2). On August 14, 2023, Summit/DFW provided emissions data, from March to August 2023 showing that the total annual volatile organic compound ("VOC") emissions recorded at the TEG dehydrator was 16.46 tons. The NRSP-PCP permit authorizes 0.55 tons per year ("tpy") VOCs from the TEG dehydrator (see AOC #6). Equipment emissions data from TEG dehydration are provided in Appendix 6. Combustors DWG operates two combustors (see Photos 2-3 in Appendix 1). The BTEX combustor controls vapors from the glycol reboiler, while the Vapor Combustion Unit ("VCU") controls vapors from the produced water tanks. Mr. Stewart stated that Summit/DFW installed both combustors at DWG in 2022. With the FLIR camera, we observed emissions from the BTEX combustor and the VCU (see MOV_0034 in 3 EPA Inspection Report - Page 4 of 34 DFW Midstream, LLC / Dalworthington Gardens Gathering Station No. 1 Inspection Date 08/02/2023 Appendix 2, AOCs #3 and #4). In the NRSP-PCP permit, Summit/DFW claims a 98% VOC destruction efficiency at one combustor under emission point number ("EPN") VC-1. In the NRSP-PCP permit application, Summit/DFW listed emissions from pilot gas, the still vent column of the glycol reboiler, and the produced water tanks under one combustor ("EPN VC-1"). The equipment inventory in the permit application identifies only one combustor at the facility (see AOC #5). Selected pages from the NRSP-PCP permit are provided in Appendix 4. Emissions data from March to August 2023 provided by Summit/DFW on August 14, 2023, show that the total annual VOC emissions recorded at VCU was 0.12 tons. The NRSP-PCP permit authorizes 0.03 tpy VOCs from the VCU for produced water tanks (see AOC #6). See Appendix 6 for VCU emissions data. Storage Vessels DWG has three produced water tanks (see Photo 6 in Appendix 1) that store liquids separated from gas at the separator and compressors. Mr. Stewart stated that the tanks share a common header and fill simultaneously. We did not observe emissions from the produced water tanks with the FLIR camera. The facility's PBR permit indicates that emissions from the three produced water tanks are uncontrolled and can vent to the atmosphere, but in NRSP-PCP permit, the VCU controls produced water tank emissions. Both the PBR and NRSP-PCP are active permits (see AOC #5). Selected pages from the NRSPPCP and PBR permits are provided in Appendices 4 and 5. Blowdown Vent DWG has a vent (see Photo 5 in Appendix 1) used for compressor blowdowns and maintenance activities. We did not observe any emissions from the vent with the FLIR camera. Fugitive Emissions Equipment emissions data provided by Summit/DFW on August 14, 2023, show that a total of 1.48 tons of VOC emissions were reported from fugitives sitewide from March to August 2023. DWG's PBR permit indicates that the facility has a 0.64 tpy VOC emission limit, as authorized under their permits (see AOC #6). Fugitive emissions data can be found in Appendix 6. Section III - AREAS OF CONCERN 1. Emissions were observed from the D-100 compressor. Summit/DFW did not list the D-100 compressor as an emission source in DWG's permits. In an email on September 13, 2023, Summit/DFW stated that the emissions were part of normal operations from the compressor piston rod packing. 2. Emissions were observed from the reboiler exhaust stack on the glycol reboiler. On September 13, 2023, Summit/DFW provided a site diagram which shows that the exhaust stack is the only emission 4 EPA Inspection Report - Page 5 of 34 DFW Midstream, LLC / Dalworthington Gardens Gathering Station No. 1 Inspection Date 08/02/2023 point from the reboiler. In the PBR and NRSP-PCP permits, the glycol reboiler (EPN GLYREG) has an emission rate of 0.05 tpy VOC. 3. Emissions were observed from the VCU. Summit/DFW claims a 98% destruction efficiency at a combustor with EPN VC-1 in the NRSP-PCP permit and confirmed that the VCU has a 98%destruction efficiency on August 14, 2023. 4. Emissions were observed from the BTEX combustor. Summit/DFW claims a 98% destruction efficiency at the combustor with EPN VC-1 in the NRSP-PCP permit. Summit/DFW confirmed that the BTEX combustor has a 98% destruction efficiency on August 29, 2023. The emission trail observed from the BTEX combustor suggests that vapors are not adequately combusting, and the BTEX combustor may not be meeting the 98% control efficiency. 5. Permit representations do not match on-site conditions or have inconsistent information. a. According to NRSP-PCP permit, a combustor controls vapors from the produced water tanks. In the PBR permit, the produced water tank vapors can emit to the atmosphere. Since both permits are active, Summit/DFW should consider updating the DWG's PBR permit to be consistent with the NRSP-PCP permit and represent on-site conditions. b. In the NRSP-PCP permit, Summit/DFW has accounted for one combustor installed at DWG and has represented multiple emissions sources directed at a single emission point. During the inspection, we observed two combustors at the facility. The VCU controls vapors from the three produced water tanks and the BTEX combustor controls vapors from the sill vent column on the glycol reboiler and the BTEX eliminator. Summit/DFW should consider updating DWG's permit(s) to match on-site conditions with two separate combustion devices and specify the emission sources routed to each combustor. 6. Equipment emissions data provided by Summit/DFW on August 14, 2023, suggest that DWG exceeded authorized annual VOC emission limits under its permits from March to August 2023 for the VCU, the TEG dehydrator, and sitewide fugitives. In an email on September 13, 2023, Summit/DFW stated that the emissions calculations are based on a 12-month rolling average, and the data provided to EPA were identified in April/May 2023 as inconsistent with past emission values. Summit/DFW has conducted new gas sampling and analyses at DWG to use in the emission calculations and is investigating the cause of the inconsistent emissions data. EPA Region 6 inspector, Aimee Boss, and inspectors-in-training, Benjamin Donaldson and I, Uma Lad, conducted a closing conference for the inspection at Summit/DFW's Dalworthington Gardens Gathering Station No. 1 at 10:50 AM on August 2, 2023. During the closing conference, I reviewed the AOCs #1 - 4 noted during the inspection. AOCs #5 and #6 were determined after the inspection and were not included in the closing conference. I informed the Summit/DFW representatives of EPA Region 6's procedures that follow the field inspection and that the inspection report would be made public on 5 EPA Inspection Report - Page 6 of 34 DFW Midstream, LLC / Dalworthington Gardens Gathering Station No. 1 Inspection Date 08/02/2023 EPA's website. We concluded the closing conference and departed the facility at 11:04 AM. The sign-in sheet for the closing conference is included as Appendix 3. Section IV - FOLLOW UP On August 7, 2023, I requested schematics, build and installation dates, standard operating procedures ("SOP"), maintenance procedures, monitoring data, and any documentation related to VCU, BTEX combustor, BTEX eliminator, glycol reboiler, and D-100 compressor. I also requested records of operation and maintenance, monitoring, and inspection records for the past six (6) months and current permit information. Mr. Castillo provided the requested information on August 14 and 18, 2023. I sent additional emails on August 21, 24, and 29 and September 7 and 12 to Mr. Castillo requesting clarification on the documents and permit information provided by Summit/DFW. Mr. Castillo responded to the additional emails. Section V - LIST OF APPENDICES Appendix 1 - Photo Log - 8 photos taken 08/02/23 Appendix 2 - Video Log - 2 FLIR videos taken 08/02/23 Appendix 3 - Opening and closing conference sign-in sheets Appendix 4 - Permit No. 166168, selected pages Appendix 5 - Permit No. 91291, selected pages Appendix 6 - Equipment emissions data, selected pages 6 EPA Inspection Report - Page 7 of 34 DFW Midstream, LLC / Dalworthington Gardens Gathering Station No. 1 Inspection Date 08/02/2023 Appendix 1 Photograph Log EPA Inspection Report - Page 8 of 34 UNITED STATES ENVIRONMENTAL PROTECTION AGENCY Photograph Log Photo No. 1 Location: DFW Midstream, LLC / Dalworthington Gardens Gathering Station No. 1 City: Dalworthington Gardens County: Tarrant County State: Texas Photo File Name: DSCN0652.JPG Date of Photo: 08/02/2023 Time of Photo: 8:58 AM Photographer: Uma Lad Description: D-100 compressor. Page 1 of 10 EPA Inspection Report - Page 9 of 34 UNITED STATES ENVIRONMENTAL PROTECTION AGENCY Photograph Log Photo No. 2 Location: DFW Midstream, LLC / Dalworthington Gardens Gathering Station No. 1 City: Dalworthington Gardens County: Tarrant County State: Texas Photo File Name: DSCN0661.JPG Date of Photo: 08/02/2023 Time of Photo: 9:30 AM Photographer: Uma Lad Description: BTEX combustor. Page 2 of 10 EPA Inspection Report - Page 10 of 34 UNITED STATES ENVIRONMENTAL PROTECTION AGENCY Photograph Log Photo No. 3 Location: DFW Midstream, LLC / Dalworthington Gardens Gathering Station No. 1 City: Dalworthington Gardens County: Tarrant County State: Texas Photo File Name: DSCN0662.JPG Date of Photo: 08/02/2023 Time of Photo: 9:31 AM Photographer: Uma Lad Description: Combustor for produced water tanks. Page 3 of 10 EPA Inspection Report - Page 11 of 34 UNITED STATES ENVIRONMENTAL PROTECTION AGENCY Photograph Log Photo No. 4 Location: DFW Midstream, LLC / Dalworthington Gardens Gathering Station No. 1 City: Dalworthington Gardens County: Tarrant County State: Texas Photo File Name: DSCN0663.JPG Date of Photo: 08/02/2023 Time of Photo: 9:32 AM Photographer: Uma Lad Description: Glycol reboiler. Page 4 of 10 EPA Inspection Report - Page 12 of 34 UNITED STATES ENVIRONMENTAL PROTECTION AGENCY Photograph Log Photo No. 5 Location: DFW Midstream, LLC / Dalworthington Gardens Gathering Station No. 1 City: Dalworthington Gardens County: Tarrant County State: Texas Photo File Name: DSCN0669.JPG Date of Photo: 08/02/2023 Time of Photo: 9:50 AM Photographer: Uma Lad Description: Blowdown vent. Page 5 of 10 EPA Inspection Report - Page 13 of 34 UNITED STATES ENVIRONMENTAL PROTECTION AGENCY Photograph Log Photo No. 6 Location: DFW Midstream, LLC / Dalworthington Gardens Gathering Station No. 1 City: Dalworthington Gardens County: Tarrant County State: Texas Photo File Name: DSCN0670.JPG Date of Photo: 08/02/2023 Time of Photo: 9:55 AM Photographer: Uma Lad Description: Produced water tanks. Page 6 of 10 EPA Inspection Report - Page 14 of 34 UNITED STATES ENVIRONMENTAL PROTECTION AGENCY Photograph Log Photo No. 7 Location: DFW Midstream, LLC / Dalworthington Gardens Gathering Station No. 1 City: Dalworthington Gardens County: Tarrant County State: Texas Photo File Name: DSCN0672.JPG Date of Photo: 08/02/2023 Time of Photo: 9:56 AM Photographer: Uma Lad Description: D-400 compressor. Page 7 of 10 EPA Inspection Report - Page 15 of 34 UNITED STATES ENVIRONMENTAL PROTECTION AGENCY Photograph Log Photo No. 8 Location: DFW Midstream, LLC / Dalworthington Gardens Gathering Station No. 1 City: Dalworthington Gardens County: Tarrant County State: Texas Photo File Name: DSCN0674.JPG Date of Photo: 08/02/2023 Time of Photo: 10:28 AM Photographer: Uma Lad Description: D-300 compressor. Page 8 of 10 EPA Inspection Report - Page 16 of 34 DFW Midstream, LLC / Dalworthington Gardens Gathering Station No. 1 Inspection Date 08/02/2023 Appendix 2 Video Log EPA Inspection Report - Page 17 of 34 UNITED STATES ENVIRONMENTAL PROTECTION AGENCY Video Log Appendix 2 Location: DFW Midstream, LLC / Dalworthington Gardens Gathering Station No. 1 City: Dalworthington Gardens County: Tarrant County State: Texas Video File Name: Facility Name: Date of Video: Time of Video: Videographer: Description: MOV_0034 Dalworthington Gardens Gathering Station No. 1 08/02/2023 10:01 AM* Aimee Boss Emissions observed from the BTEX combustor, reboiler stack, and combustor for the produced water tanks. Video File Name: Facility Name: Date of Video: Time of Video: Videographer: Description: MOV_0035 Dalworthington Gardens Gathering Station No. 1 08/02/2023 10:12 AM* Aimee Boss Emissions and heat observed from the D-100 compressor. *Metadata time is reported in Greenwich Mean Time and reflected in Central Standard Time here. Page 1 of 1 EPA Inspection Report - Page 18 of 34 DFW Midstream, LLC / Dalworthington Gardens Gathering Station No. 1 Inspection Date 08/02/2023 Appendix 3 Opening and Closing Conference Sign-In Sheets EPA Inspection Report - Page 19 of 34 EPA Inspection Report - Page 20 of 34 EPA Inspection Report - Page 21 of 34 DFW Midstream, LLC / Dalworthington Gardens Gathering Station No. 1 Inspection Date 08/02/2023 Appendix 4 Permit No. 166168, selected pages EPA Inspection Report - Page 22 of 34 DFW Midstream Services LLC Dalworthington Gardens Gathering Station No. 1 NRSP PCP Application August 2021 Section 1 - Site/Project Information Project Description DFW Midstream Services LLC ("DFW Midstream") owns and operates the Dalworthington Gardens Gathering Station No. 1 ("the site") in Tarrant County, Texas. The site is an existing oil and gas site that consists of the emission sources listed in Table 1 of this Section. The purpose of this submittal is to register and certify an addition of a control device under the Non Rule Standard Permit PCP. The revisions include adding a control device to the onsite storage tanks and glycol dehydrator and associated fugitives. Uncontrolled emission rates sent to the control device will maintain as previously registered and certified under the Permit by Rule ("PBR") Registration No. 91291. The attached application includes administrative documents, including required TCEQ forms, followed by the technical documents in support of this registration. Addition of the following emission source(s): Control device for the glycol dehydrator and storage tanks (EPN: VC-1) New fugitive emissions associated with the new control device (EPN: FUG) The following emission source(s) remain unchanged under PBR 91291: Glycol Regenerator (EPN: GLYREG) Compressor Oil Tanks (EPNs: COMP-OIL-1 through COMP-OIL-3) TEG Slop Tanks (EPNs: TEG-1 and TEG-2) Methanol Storage Tank (EPN: METHANOL-1) Mineral Oil Tanks (EPN: MIN-OIL-1 and MIN-OIL-2) MSS Activities (EPNs: LEMSS, BLWDWN) Glycol Dehydrator (FIN: GLYCOL) Produced Water Tanks (FINs: TK-001, TK-002, and TK-003) Produced Water Loading (EPN: LOAD) Site-wide Fugitives (EPN: FUG) The documentation included in this application demonstrates compliance with all applicable state and federal standards. Process Description - Routine Operations The Dalworthington Gardens Gathering Station No. 1 is primarily a dehydration treating and natural gas compressor station. Sweet natural gas enters the facility through a slug catcher and a series of electric motor driven compressors (two (2) 2,500 hp, and one (1) 6,000 hp). The compressed gas then enters the TEG dehydrator (FIN: GLYCOL) to remove water from the gas stream. The dry dehydrated gas stream is sent to the sales line through a 200 hp electric driven compressor engine. The rich TEG is regenerated by a gas-fired glycol reboiler rated at 2.0 MMBtu/hr (EPN: GLYREG). Glycol flash tank vapors are controlled by the regenerator firebox, which reduces VOC emissions with a 50% control efficiency. The regenerator overhead vapors are routed to the BTEX eliminator and vapor combustor (EPN: VC1) for a minimum of 98% destruction. Produced water separated from the compression process and from the dehydration process is directed into one (1) of three (3) 300 bbl water tanks. The water tank emissions are manifolded and routed to a combustion device (EPN: VC-1) for a minimum of 98% destruction. Produced water is removed from the site by tank truck and all loading vapors are vented to atmosphere (EPN: LOAD). Other sources of emissions at this site include fugitive component emissions (EPN: FUG), two (2) TEG storage tanks (EPNs: TEG-1 and TEG-2), three (3) compressor oil storage tanks (EPNs: COMP-OIL- 1 through COMP-OIL-3), a methanol storage tank (EPN: METHANOL-1), two (2) mineral oil tanks (EPNs: MIN-OIL-1 and MIN-OIL-2), and planned MSS activities, including compressor blowdowns (EPN: BLWDWN) and low emitting MSS (EPN: LEMSS). Simplified process flow diagrams are provided in this section. EPA Inspection Report - Page 23 of 34 Inlet Gas Slug Catcher Electric-Driven Compressor(s) Electric-Driven Compressor(s) Sales Pipeline BTEX Condensor TEG Dehydrator GLYCOL Glycol Regenerator lean glycol GLYREG rich glycol Flash Tank Vapor Combustor VC-1 Produced Water Tanks TK-001 through TK-003 Produced Water Truck Loadout LOAD Additional emission sources at the site include: - Fugitives (FUG) - MSS (LEMSS, BLWDWN) - Miscellanous Tanks Dalworthington Gardens Gathering Station No. 1 32.7086878N, 97.1565236W Tarrant County, Texas DFW Midstream Services LLC Figure 1-1 Process Flow Diagram PROJECT NO. DRAFTED BY REVIEWED BY DATE 20487.00A NRN ELN 8/3/2021 Full Stream Vapors Produced Oil/Condensat Produced Gas EPA Inspection Report - Page 24 of 34 DFW Midstream Services LLC Dalworthington Gardens Gathering Station No. 1 Section 1 - Site/Project Information Table 1. Site Equipment/Processes Equipment/Process Fugitives Heaters-Boiler(s) Quantity yes 1 Glycol Unit 1 Produced Water Storage Tanks 3 Miscellaneous Storage Tanks 8 Loading Job(s) 1 Vapor Combustor(s) 1 Planned MSS Activity yes FIN FUG GLYREG GLYCOL GLYCOL TK-001 TK-002 TK-003 COMP-OIL-1 COMP-OIL-2 COMP-OIL-3 TEG-1 TEG-2 METHANOL-1 MIN-OIL-1 MIN-OIL-2 LOAD VC-1 LEMSS BLWDWN NRSP PCP Application August 2021 EPN FUG GLYREG VC-1 GLYREG VC-1 VC-1 VC-1 COMP-OIL-1 COMP-OIL-2 COMP-OIL-3 TEG-1 TEG-2 METHANOL-1 MIN-OIL-1 MIN-OIL-2 LOAD VC-1 LEMSS BLWDWN EPA Inspection Report - Page 25 of 34 DFW Midstream Services LLC Dalworthington Gardens Gathering Station No. 1 Emissions Summary Table EMISSION SOURCES EPN FIN Emission Source Name Total VOC [1] lb/hr tpy Project Sources: Added/Revised Emissions to be Authorized under Permit No. TBD FUG FUG Fugitives (VC Addition Only) 0.03 VC-1 Pilot (Field Gas) <0.01 VC-1 GLYCOL Still Vent <0.01 PW Tanks [3] Controlled Produced Water Tanks 0.01 Sources Not Affected by the Project Authorized under Permit No. 91291 FUG FUG Existing Fugitives GLYREG GLYREG Glycol Regenerator COMP-OIL-1 COMP-OIL-1 Compressor Oil Tank COMP-OIL-2 COMP-OIL-2 Compressor Oil Tank COMP-OIL-3 COMP-OIL-3 Compressor Oil Tank TEG-1 TEG-1 TEG Slop Tank TEG-2 TEG-2 TEG Slop Tank METHANOL-1 METHANOL-1 Methanol Storage Tank MIN-OIL-1 MIN-OIL-1 Mineral Oil Tank MIN-OIL-2 MIN-OIL-2 Mineral Oil Tank LEMSS LEMSS Low Emitting MSS BLWDWN BLWDWN Blowdowns GLYREG GLYCOL Glycol Dehydrator (Flash Tank) LOAD LOAD PW Loading 0.15 0.01 0.03 0.03 0.03 0.03 0.03 1.50 0.09 0.01 0.04 28.85 0.10 0.12 Estimated Total Emissions 31.05 0.13 <0.01 <0.01 0.03 0.64 0.05 <0.01 <0.01 <0.01 <0.01 <0.01 0.14 0.01 <0.01 0.16 3.46 0.42 0.02 5.08 Major Source Threshold Total Emissions Limit Below major source threshold? [1] Total VOC include HAPs. [2] Total HAPs include benzene. [3] Storage tanks controlled by VC-1: TK-001, TK-002, TK-003 100.0 Yes NOx lb/hr tpy -<0.01 0.01 0.06 -0.20 ------------- 0.27 -<0.01 0.05 0.24 -0.90 ------------- 1.20 100.0 Yes CO lb/hr tpy -- -- 0.01 0.04 0.10 0.44 0.11 0.49 -- -- 0.17 0.75 -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 0.39 1.71 100.0 Yes ESTIMATED EMISSION RATES PM10/PM2.5 SO2 lb/hr tpy lb/hr tpy -<0.01 <0.01 <0.01 -0.02 ------------- 0.02 -<0.01 0.01 0.01 -0.07 ------------- 0.09 100.0 Yes -<0.01 <0.01 -- -<0.01 ------------- <0.01 -<0.01 0.01 -- -<0.01 ------------- 0.01 100.0 Yes H2S lb/hr tpy <0.01 <0.01 <0.01 -- <0.01 ------------ <0.01 -- <0.01 <0.01 <0.01 <0.01 -- <0.01 ------------ <0.01 -- <0.01 100.0 Yes NRSP PCP Application August 2021 Benzene lb/hr tpy Total HAPs [2] lb/hr tpy ---<0.01 <0.01 -------------- <0.01 ---<0.01 <0.01 -------------- <0.01 10.0 Yes <0.01 --- <0.01 <0.01 -------------- <0.01 <0.01 ---- <0.01 -------------- <0.01 25.0 Yes EPA Inspection Report - Page 26 of 34 DFW Midstream, LLC / Dalworthington Gardens Gathering Station No. 1 Inspection Date 08/02/2023 Appendix 5 Permit No. 91291, selected pages EPA Inspection Report - Page 27 of 34 DFW Midstream Services LLC, CN603578618 Dalworthington Gardens Gathering Station No. 1 Permit by Rule Revision Registration Introduction 1.0 Introduction 1.1 Project Overview DFW Midstream Services LLC ("DFW Midstream"), a subsidiary of Summit Midstream Partners, LP ("Summit"), owns and operates the Dalworthington Gardens Gathering Station No. 1 ("the site") in Tarrant County, Texas. The site is primarily a natural gas compressor station located in the Barnett Shale formation that is currently authorized under 30 TAC 106.352(a)-(k) (PBR Registration No. 91291). DFW Midstream is requesting to register and certify the updates outlined in the section under PBR Registration No. 91291 with this application. The proposed updates with this application include the addition of emissions from the following sources: Three (3) compressor oil storage tanks (FIN: COMP-OIL-1, COMP-OIL-2, COMP-OIL-3) One (1) methanol storage tank (FIN: METHANOL-1) Two (2) TEG slop tanks (FIN: TEG-1, TEG-2) Two (2) mineral oil storage tanks (FIN: MIN-OIL-1, MIN-OIL-2) The purpose of this project is to authorize emissions from additional sources while emissions from the previously registered sources remain unchanged. Emission calculations for the following unchanged sources are not included in this registration: One (1) TEG dehydrator reboiler stabilizer heater Three (3) produced water storage tanks One (1) produced water loading job One (1) TEG dehydrator Compressor blowdowns Facility blowdowns Site-wide fugitive emissions Low-emitting MSS The emissions summary Table 3-2 in Section 3.0 of this application includes site-wide emissions. The documentation included in this application demonstrates compliance with all applicable state and federal standards. Spirit Environmental, LLC 18317.00A August 2018 1-1 EPA Inspection Report - Page 28 of 34 DFW Midstream Services LLC, CN603578618 Dalworthington Gardens Gathering Station No. 1 Permit by Rule Revision Registration Site Process Information 2.0 Site Process Information 2.1 Process Description The Dalworthington Gardens Gathering Station No. 1 is primarily a dehydration treating and natural gas compressor station. A simplified process flow diagram illustrating the site process at the Dalworthington Gardens Gathering Station No. 1 is provided as Figure 2-1 and a summary of EPNs, FINs, and a description of each new and updated source is presented in Table 3-1. Sweet natural gas enters the facility through a slug catcher and a series of electric motor driven compressors (two (2) 2,500 hp, and one (1) 6,000 hp). The compressed gas then enters the TEG dehydrator (EPN: GLYCOL) to remove water from the gas stream. The dry dehydrated gas stream is sent to the sales line through a 200 hp electric driven compressor engine. The rich TEG is regenerated by a gas-fired glycol reboiler rated at 2.0 MMBtu/hr (EPN: GLYREG). Glycol flash tank vapors are controlled by the regenerator firebox, which reduces VOC emissions with a 50% control efficiency. The regenerator overhead vapors are routed to the BTEX eliminator for further control, which reduces the vent stream VOC emissions by 90%. Produced water separated from the compression process and from the dehydration process is directed into one of three (3) 300 bbl water tanks. The water tanks vent to atmosphere through a common stack used for equipment blowdowns (EPN: BLWDWN). Produced water is removed from the site by tank truck and all loading vapors are vented to atmosphere (EPN: LOAD). Other sources of emissions at this site include fugitive component emissions (EPN: FUG), two (2) TEG storage tanks (EPNs: TEG-1, TEG-2), three (3) compressor oil storage tanks (EPN: COMPOIL-1 through COMP-OIL-3), a methanol storage tank (EPN: METHANOL-1), two (2) mineral oil tanks, and planned MSS activities, including compressor blowdowns (EPN: BLWDWN) and lowemitting MSS (EPN: LEMSS). Spirit Environmental, LLC 18317.00A August 2018 2-1 EPA Inspection Report - Page 29 of 34 Sales Gas Controlled Emissions Inlet Gas Gas Slug Catcher Electric Compressor Gas Electric Gas Compressors TEG Dehydrator BTEX Eliminator (Condenser) Lean Glycol Glycol Regenerator Reboiler Emissions Rich Glycol Flash Tank Water F/W/B Losses Water Tanks Loading Emissions Loading Fugitives NOTE: F/W/B - Flash, Working, & Breathing Losses Process Flow Diagram Air Quality Permit Registration Dalworthington, Tarrant County, Texas DFW Midstream Services LLC Dalworthington Gardens Gathering Station No.1 EPA Inspection Report - Page 30 of 34 DFW Midstream Services LLC Dalworthington Gardens Gathering Station No. 1 Table 3-2 Emissions Summary Table EPN FUG GLYREG BLWDWN BLWDWN BLWDWN LOAD GLYCOL BLWDWN Low Emitting MSS COMP-OIL-1 COMP-OIL-2 COMP-OIL-3 TEG-1 TEG-2 METHANOL-1 MIN-OIL-1 MIN-OIL-2 Emission Source Name Sitewide Fugitives Glycol Regenerator Water Tank 1 Water Tank 2 Water Tank 3 Produced Water Loading Emissions TEG Dehydrator Blowdowns LEMSS Compressor Oil Tank Compressor Oil Tank Compressor Oil Tank TEG Slop Tank TEG Slop Tank Methanol Storage Tank Mineral Oil Tank Mineral Oil Tank Total emissions Total VOC NOx CO PM10/PM2.5 lb/hr tpy lb/hr tpy lb/hr tpy lb/hr tpy Authorized/Unchanged Emission Sources 0.15 0.64 -- -- -- -- -- -- 0.01 0.05 0.20 0.90 0.17 0.75 0.02 0.07 0.11 0.48 -- -- -- -- -- -- 0.11 0.48 -- -- -- -- -- -- 0.11 0.48 -- -- -- -- -- -- 0.12 0.02 -- -- -- -- -- -- 0.13 0.55 -- -- -- -- -- -- 28.85 3.46 -- -- -- -- -- -- 0.04 0.16 -- -- -- -- -- -- Added Emissions Sources 0.03 <0.01 -- -- -- -- -- -- 0.03 <0.01 -- -- -- -- -- -- 0.03 <0.01 -- -- -- -- -- -- 0.03 <0.01 -- -- -- -- -- -- 0.03 <0.01 -- -- -- -- -- -- 1.50 0.14 -- -- -- -- -- -- 0.09 0.01 -- -- -- -- -- -- 0.01 <0.01 -- -- -- -- -- -- 31.37 6.47 0.20 0.90 0.17 0.75 0.02 0.07 Total emissions Project Sources 1.75 0.16 -- -- -- Steady-state 2.48 2.86 0.20 0.90 0.17 0.75 0.02 0.07 Estimated Emissions < 30 psig periodic releases, up to 150 hrs per year 28.89 3.62 -- -- -- -- -- -- 30 psig periodic releases, up to 150 -- -- -- -- -- -- -- -hrs per year Below permit limits? Yes Yes Yes Yes Yes Yes Yes Yes Total emissions 15.0 100.0 100.0 5.0 PBR-106.352(a)-(k), L1 Emission Limits Steady-state < 30 psig periodic releases, up to 150 hrs per year 30 psig periodic releases, up to 150 hrs per year 43.2 45.0 10.0 SO2 lb/hr tpy -<0.01 -------- --------<0.01 -- <0.01 -- -- Yes 47.0 93.2 -<0.01 -------- --------<0.01 <0.01 -- -- Yes 25.0 H2S lb/hr tpy <0.01 ----<0.01 0.05 -- --------0.05 -- <0.01 0.05 -- Yes 4.7 5.1 9.8 <0.01 ----0.01 0.01 -- --------0.01 0.01 0.01 -- Yes 20.6 Benzene lb/hr tpy <0.01 <0.01 <0.01 <0.01 ----- --------<0.01 -- <0.01 -- -- Yes 2.0 7.0 15.4 <0.01 <0.01 <0.01 <0.01 ----- --------0.01 0.01 -- -- Yes 2.8 EPA Inspection Report - Page 31 of 34 DFW Midstream, LLC / Dalworthington Gardens Gathering Station No. 1 Inspection Date 08/02/2023 Appendix 6 Equipment Emissions Data EPA Inspection Report - Page 32 of 34 Equipment Compliance Review Report Date: 8/8/2023 11:59:59 PM Operational Data or Pollutant Units Operational Data Runtime hr/month Emission Data Criteria Pollutants Carbon Monoxide ton Nitrogen Oxides ton VOC ton 6-Month Period from Mar 2023 to Aug 2023 DFW Midstream Services LLC Facility: DWG Compressor Station, Combustor: CB-1, Tanks Combustor, (Active) De Minimis: No (Where applicable, red color indicates noncompliance with limit) Monthly Limit Mar 2023 Apr 2023 May 2023 Jun 2023 Jul 2023 Aug 2023 744.00 720.00 744.00 720.00 744.00 744.00 Page 1 of 8 Annual Total Annual Limit 4416.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.02 0.02 0.02 0.02 0.02 0.02 0.12 EPA Inspection Report - Page 33 of 34 Equipment Compliance Review Report Date: 8/8/2023 11:59:59 PM Operational Data or Pollutant Units Operational Data Gas Throughput Runtime Stripping Gas mmscf/month hr/month % Emission Data Criteria Pollutants VOC ton HAPS Benzene lb n-Hexane lb Toluene lb Xylenes lb Monthly Limit 6-Month Period from Mar 2023 to Aug 2023 DFW Midstream Services LLC Facility: DWG Compressor Station, Dehydrator: GLY1, TEG Dehy, (Active) De Minimis: No (Where applicable, red color indicates noncompliance with limit) Mar 2023 Apr 2023 May 2023 Jun 2023 Jul 2023 Aug 2023 1171.51 1114.68 1102.84 564.71 0.00 0.00 742.97 719.80 743.82 719.78 743.80 0.00 100.00 100.00 100.00 100.00 0.00 0.00 Page 2 of 8 Annual Total Annual Limit 3953.74 3670.17 100.00 4.27 4.19 4.54 3.46 0.00 0.00 16.46 0.55 829.44 819.44 894.03 626.28 0.00 0.00 72.76 74.35 82.63 68.55 0.00 0.00 1289.00 1263.91 1362.38 897.54 0.00 0.00 2866.21 2775.48 2916.53 1751.65 0.00 0.00 3169.19 298.29 4812.83 10309.87 EPA Inspection Report - Page 34 of 34 Equipment Compliance Review Report Date: 8/8/2023 11:59:59 PM Operational Data or Pollutant Units Emission Data Criteria Pollutants VOC ton HAPS 2,2,4-Trimethylpentane lb Benzene lb Ethylbenzene lb n-Hexane lb Toluene lb Xylenes lb Monthly Limit 6-Month Period from Mar 2023 to Aug 2023 DFW Midstream Services LLC Facility: DWG Compressor Station, Fugitive: FUG-1, , Sitewide Fugitives (Active) De Minimis: No (Where applicable, red color indicates noncompliance with limit) Mar 2023 Apr 2023 May 2023 Jun 2023 Jul 2023 Aug 2023 Page 3 of 8 Annual Total Annual Limit 0.25 0.00 20.43 0.00 11.65 24.96 34.65 0.24 0.00 19.77 0.00 11.27 24.16 33.53 0.25 0.00 20.43 0.00 11.65 24.96 34.65 0.24 0.00 19.77 0.00 11.27 24.16 33.53 0.25 0.00 20.43 0.00 11.65 24.96 34.65 0.25 0.00 20.43 0.00 11.65 24.96 34.65 1.48 0.00 121.26 0.00 69.14 148.16 205.66 0.64 20.00