DAQ-2024-011505

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DAQC-CI102680001-24
Site ID 10268 (B1)

MEMORANDUM

TO: FILE – UGC MIDSTREAM, LTD, LLC – San Arroyo Plant

THROUGH: Rik Ombach, Minor Source Oil and Gas Compliance Section Manager

FROM: Kyle Greenberg, Environmental Scientist

DATE: November 6, 2024

SUBJECT: FULL COMPLIANCE EVALUATION, Minor, Grand County

INSPECTION DATE: September 24, 2024

SOURCE LOCATION: SE/4 NW/4 Sec. 23, T16S, R25E
Westwater, UT 84515
DIRECTIONS: UTM Coordinates: 661,080 Easting; 4,363,287 Northing

SOURCE CONTACTS: Taryn Weiner, Regulatory Coordinator
[e-mail]
Phone: [phone]

OPERATING STATUS: Operating.

PROCESS DESCRIPTION: The San Arroyo Plant receives natural gas from various locations
by two 6 inch pipeline inlets. The gas enters an inlet scrubber
system and is then compressed. The gas is then sent to
Westwater Bar X.

APPLICABLE REGULATIONS: Approval Order (AO) DAQE-AN102680013-21, dated
November 16, 2021
NSPS (Part 60) -JJJJ : Standards of Performance for Stationary
Spark Ignition Internal Combustion Engines,

SOURCE EVALUATION:

Name of Permittee: Permitted Location:

UGC Midstream, LTD, LLC - San Arroyo Plant
760 Horizon Drive, Suite 400 SE/4 NW/4 Sec. 23, T16S, R25E
Grand Junction, CO 81506 Westwater, UT 84515

SIC Code: 4922 (Natural Gas Transmission)

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Section I: GENERAL PROVISIONS

I.1 All definitions, terms, abbreviations, and references used in this AO conform to those used in the UAC R307 and 40 CFR. Unless noted otherwise, references cited in these AO conditions refer to those rules. [R307-101]
I.2 The limits set forth in this AO shall not be exceeded without prior approval. [R307-401]
I.3 Modifications to the equipment or processes approved by this AO that could affect the emissions covered by this AO must be reviewed and approved. [R307-401-1]
I.4 All records referenced in this AO or in other applicable rules, which are required to be kept by the owner/operator, shall be made available to the Director or Director's representative upon request, and the records shall include the two-year period prior to the date of the request. Unless otherwise specified in this AO or in other applicable state and federal rules, records shall be kept for a minimum of two (2) years. [R307-401-8]
I.5 At all times, including periods of startup, shutdown, and malfunction, owners and operators shall, to the extent practicable, maintain and operate any equipment approved under this AO, including associated air pollution control equipment, in a manner consistent with good air pollution control practice for minimizing emissions. Determination of whether acceptable operating and maintenance procedures are being used will be based on information available to the Director which may include, but is not limited to, monitoring results, opacity observations, review of operating and maintenance procedures, and inspection of the source. All maintenance performed on equipment authorized by this AO shall be recorded. [R307-401-4]
I.6 The owner/operator shall comply with UAC R307-107. General Requirements: Breakdowns. [R307-107]
I.7 The owner/operator shall comply with UAC R307-150 Series. Emission Inventories. [R307-150]
I.8 The owner/operator shall submit documentation of the status of construction or modification to the Director within 18 months from the date of this AO. This AO may become invalid if construction is not commenced within 18 months from the date of this AO or if construction is discontinued for 18 months or more. To ensure proper credit when notifying the Director, send the documentation to the Director, attn.: NSR Section. [R307-401-18] Status: In Compliance. In compliance with all conditions of Section I. Emission inventories, referenced in condition 1.7, are not currently required at this source in Grand County. The following records were made available upon request and have been attached to this memo: condensate throughput, thief hatch inspection records, and engine maintenance records.

Section II: SPECIAL PROVISIONS

II.A The approved installations shall consist of the following equipment:

II.A.1 San Arroyo Plant Natural gas compression facility
II.A.2 Compressor Engine (NEW) Maximum rating: 1260 hp Fuel: Natural Gas NSPS Applicability: Subpart JJJJ MACT Applicability: Subpart ZZZZ
II.A.3 Compressor Engine Maximum Rating: 101 hp Fuel: Natural Gas NSPS Applicability: Subpart OOOOa MACT Applicability: Subpart ZZZZ
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II.A.4 Two (2) Tanks (T-8) Methanol Storage Tanks Capacity: Approximately 500 gallons, each
II.A.5 Tank (T-9) Pre-November1969 Drain sump storage tank
II.A.6 Five (5) Tanks (T-10 thru T-14) Process Tanks Capacity:1,000 gallons or less, each Contents: Methanol, new lube oil, used oil, antifreeze
II.A.7 Tank (T-4101) Pre-November1969 Condensate storage tank Approximate capacity: 210 barrels (8,820 gallons)
II.A.8 Tank (T-4102) Pre-November1969 Condensate storage tank Approximate capacity: 300 barrels (12,600 gallons)
II.A.9 Tank (T-4103) Condensate storage tank Approximate capacity: 244 barrels (10,248 gallons)
II.A.10 Slop Oil Tank Maximum capacity: 70 barrels (2,940 gallons) Status: In Compliance. The 101 hp compressor engine is out of service and locked out and the 70 barrel slop oil tank has been removed. All other listed equipment is on-site.

II.B Requirements and Limitations
II.B.1 Site Wide Requirement II.B.1.a The owner/operator shall not allow visible emissions from the indicated emission points to exceed the following values: A. All tanks - 10% Opacity B. All other emissions points - 20% Opacity. [R307-401-8] II.B.1.a.1 Opacity observations of emissions from stationary sources shall be conducted according to 40 CFR 60, Appendix A, Method 9. [R307-201-3] Status: In Compliance. AVO records reviewed by UGC show the VEO limits of 10% opacity for tanks and 20% opacity for the compressor engine have not been exceeded. II.B.2 Compressor Engine Requirement II.B.2.a The owner/operator shall not exceed the following emission rates from the indicated emission point: Source: Caterpillar G3516 TALE Natural Gas Compressor Engine Pollutant lb/hr (g/bhp-hr) NOx 5.6 (2) CO 3.4 (1.20). [R307-401-8]
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II.B.2.b To demonstrate compliance with the emission limitations above, the owner/operator shall conduct stack testing (emission testing) as outlined in this AO. [R307-401-8] II.B.2.b.1 Initial Test The owner/operator shall conduct an initial stack test within 180 days after startup. [R307-165-2] II.B.2.b.2 Test Frequency The owner/operator shall conduct subsequent stack tests within five years after the date of the most recent stack test. The Director may require the owner/operator to perform a stack test at any time. [R307-165-2, R307-401-8] Status: In Compliance. An initial performance test on the Caterpillar G3516 TALE Natural Gas Compressor Engine was conducted on May 2, 2023 (DAQC-667-23). II.B.3 Stack Testing II.B.3.a The owner/operator shall conduct any stack testing required by this AO according to the following conditions. [R307-401-8] II.B.3.a.1 Notification At least 30 days prior to conducting a stack test, the owner/operator shall submit a source test protocol to the Director. The source test protocol shall include the items contained in R307-165-3. If directed by the Director, the owner/operator shall attend a pretest conference. [R307-165-3, R307-401-8] II.B.3.a.2 Testing & Test Conditions The owner/operator shall conduct testing according to the approved source test protocol and according to the test conditions contained in R307-165-4. [R307-165-4, R307-401-8] II.B.3.a.3 Access The owner/operator shall provide Occupational Safety and Health Administration (OSHA)- or Mine Safety and Health Administration (MSHA)-approved access to the test location. [R307-401-8] II.B.3.a.4 Reporting No later than 60 days after completing a stack test, the owner/operator shall submit a written report of the results from the stack testing to the Director. The report shall include validated results and supporting information. [R307-165-5, R307-401-8] II.B.3.a.5 Possible Rejection of Test Results The Director may reject stack testing results if the test did not follow the approved source test protocol or for a reason specified in R307-165-6. [R307-165-6, R307-401-8] II.B.3.a.6 Standard Conditions A. Temperature - 68 degrees Fahrenheit (293 K) B. Pressure - 29.92 in Hg (101.3 kPa) C. Averaging Time - As specified in the applicable test method [40 CFR 60 Subpart A, 40 CFR 63 Subpart A, R307-401-8] II.B.3.b Test Methods When performing stack testing, the owner/operator shall use the appropriate EPA-approved test methods as acceptable to the Director. Acceptable test methods for pollutants are listed below. [R307-401-8] II.B.3.b.1 NOx 40 CFR 60, Appendix A, Method 7; Method 7E; or other EPA-approved testing method as acceptable to the Director. [R307-401-8]
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II.B.3.b.2 CO 40 CFR 60, Appendix A, Method 10 or other EPA-approved testing method as acceptable to the Director. [R307-401-8] Status: In Compliance. The initial performance test shows the Caterpillar G3516 TALE Natural Gas Compressor Engine to be in compliance with its emission limits (DAQC-667-23).
Section III: APPLICABLE FEDERAL REQUIREMENTS

In addition to the requirements of this AO, all applicable provisions of the following federal programs
have been found to apply to this installation. This AO in no way releases the owner or operator from any
liability for compliance with all other applicable federal, state, and local regulations including UAC
R307.

NSPS (Part 60) -JJJJ : Standards of Performance for Stationary Spark Ignition Internal Combustion Engines

Status: In Compliance. An initial performance test was conducted on the Caterpillar G3516 TALE
Natural Gas Compressor Engine on May 2, 2023, and the test shows the engine to be in compliance with
Subpart JJJJ emission limits (DAQC-667-23). Regular maintenance is conducted on the engine, see
attached records.

40 CFR Part 60 Subpart OOOOa: Standards of Performance for Crude Oil and Natural Gas Facilities for
which Construction, Modification or Reconstruction Commenced After September 18, 2015

Status: In Compliance. The 101 hp compressor engine is required to have the rod packing replaced
before it is put back in service. UGC has stated that they are aware of this and will replace the rod
packing before putting it in service. UGC has no current plans to put the 101 hp compressor engine
back in service. The 1260 hp compressor engine is a replacement-in-kind and Subpart OOOOa is not
applicable to it. UGC has stated that the rod packing seals for the 1260 hp compressor engine will be
replaced in the upcoming months. See attached records of thief hatch inspections and condensate
throughput.

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AREA SOURCE RULES EVALUATION:

The following Area Source Rules were evaluated during this inspection:

EMISSION INVENTORY:
The emissions listed below are an estimate of the total potential emissions (PTE) from UGC Midstream,
LTD, LLC - San Arroyo Plant on the Approval Order (AO) DAQE-AN102680013-21, dated November
17, 2021. PTE are supplied for supplemental purposes only.

Criteria Pollutant PTE tons/yr
CO2 Equivalent 15045.00
Carbon Monoxide 17.33
Nitrogen Oxides 28.62
Particulate Matter - PM10 0.42
Particulate Matter - PM2.5 0.42
Sulfur Dioxide 0.03
Volatile Organic Compounds 26.48

Hazardous Air Pollutant PTE lbs/yr
Acetaldehyde (CAS #75070) 720
Formaldehyde (CAS #50000) 9820
Generic HAPs (CAS #GHAPS) 3880
Hexane (CAS #110543) 400

PREVIOUS ENFORCEMENT
ACTIONS: CA - DAQC-352-23 – March 28, 2023
ESA - DAQC-810-23 – August 9, 2023
Signed ESA - DAQC-810-23 – September 5, 2023

COMPLIANCE STATUS &
RECOMMENDATIONS: In regards to Approval Order (AO) DAQE-AN102680013-21,
dated November 17, 2021: In Compliance. An initial
performance test was conducted on the Caterpillar G3516 TALE
Natural Gas Compressor Engine. The condensate throughput for
this site is below 2,000 bbls and the tanks do not require
controls.

HPV STATUS: Not Applicable.

RECOMMENDATION FOR
NEXT INSPECTION: If the 101 hp compressor engine is put back into service, check
that the rod packing was replaced before startup.

ATTACHMENTS: Engine Maintenance Records, Condensate Throughput Records,
Thief Hatch Inspection Records
Date Gross Bbls
Sold
2/23/2024 145.56
2/23/2024 61.95
6/11/2024 220
9/20/2024 241.67
669.18
Month
Thief Hatch and
PRV In Good
Condition?
Jan-24 Yes
Feb-24 Yes
Mar-24 Yes
Apr-24 Yes
May-24 Yes
Jun-24 Yes
Jul-24 Yes
Aug-24 Yes
Sep-24 Yes