Air Pollution Control (2023)

Air Pollution Control

Title V Permit to Operate

Statement of Basis for Permit No V-SUIT-0013-2023.00

March 12, 2024

Transwestern Pipeline Company, LLC

La Plata A Compressor Station

Southern Ute Indian Reservation

La Plata County, Colorado

1. Facility Information

a. Location

The La Plata A Compressor Station, owned and operated by Transwestern Pipeline Company

(Transwestern) is located within the exterior boundary of the Southern Ute Indian Reservation. The exact

location is Section 35, T34N, R9W, in La Plata County, at latitude North 37.145756 and longitude West

107.787152. The Mailing address is:

b. Contacts

Facility Contact:

Mr. Kerry Egan

Sr. Environmental Specialist

Transwestern Pipeline Company

8501 Jefferson NE

Albuquerque, NM 87113

(505) 260-4023

Transwestern Pipeline Company

La Plata A Compressor Station

8501 Jefferson St NE

Albuquerque, NM 87113

Responsible Official:

Dave Roybal

Director – Operations

Transwestern Pipeline Company

8501 Jefferson NE

Albuquerque, NM 87113

575-347-6514

c. Description of Operations

The La Plata A Compressor Station is a natural gas compression and transmission facility. Natural gas is

received at the station via pipeline and passes through an inlet separator, which separates and removes

pipeline condensate that may exist in the inlet stream. Very little liquid is contained in the gas received at

this station, so consequently, very little liquid is separated out from the gas stream for subsequent storage

and disposal. The gas is then compressed by two turbine-driven gas compressors. After compression, the

gas exits the facility via a single gas pipeline.

Any liquid removed by the separators is directed to a 100-barrel oily wastewater storage tank, which is

also used to store wastewater accumulated at the station and waste oil that accumulates from

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maintenance activity at the station. This liquid is periodically transferred to tanker trucks for off-site

disposal via a truck loading point.

The primary emitters at this facility are the two turbine-driven gas compressor engines (units T01 and

T02). There is also an emergency engine and several tanks that qualify as insignificant emission sources

located at the facility.

d. List of All Units and Emission-Generating Activities

Transwestern provided the information contained in Tables 1 and 2 in its Part 70 permit renewal

application. Table 1 lists emission units and emission generating activities, including any air pollution

control devices. Emission units identified as “insignificant” emitting units (IEUs) are listed separately in

Table 2.

Emission

Unit ID

Table 1 – Emission Units

Transwestern Pipeline Company, La Plata A Compressor Station

Description

Solar Centaur 50-H T-5502 Natural Gas-Fired Simple Cycle Turbine

5,096 HP (46 MMBtu/hr)

T01

Package Serial No.

TC95O17

Install Date:

Package Serial No.

HC90783

Install Date:

None

12/22/2021

Solar Taurus 60 7002S Natural Gas-Fired Simple Cycle Turbine

5,866 HP (49.2 MMBtu/hr)

T02

Control

Equipment

5/5/2023

SoLoNOx

(not enforceable)

The Southern Ute Indian Tribe/State of Colorado Environmental Commission’s Reservation Air Code

allows sources to separately list in the permit application units or activities that qualify as “insignificant”

based on potential emissions below 2 tpy for all regulated pollutants that are not listed as hazardous air

pollutants (HAPs) under Section 112(b) of the Clean Air Act (CAA) and below 1,000 lbs per year or the

de minimis level established under Section 112(g), whichever is lower, for HAP emissions

[RAC 2-106(4)(f); RAC 1-103(36) and (37)]. However, the application may not omit information needed

to determine the applicability of, or to impose, any applicable requirement, or to calculate the fee

[RAC 2-106(4)(f)]. Units that qualify as “insignificant” for the purposes of the Part 70 application are in

no way exempt from applicable requirements or any requirements of the Part 70 permit.

Transwestern stated in its Part 70 permit renewal application that the emission units in Table 2, below, are

insignificant. The application provided calculations for heater/reboiler emissions based on EPA’s AP-42

emission factors. Transwestern provided sufficient information, including EPA Tanks 4.0.9d calculations,

to verify any emissions from liquids in the tanks were insignificant. This data supports Transwestern’s

claim that these units qualify as insignificant.

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Table 2 – Insignificant Emission Units

Transwestern Pipeline Company, La Plata A Compressor Station

Emission Unit

ID

Amount

GEN1

1

HEATER

1

T-1

1

T-2

1

LOADING

1

BLOWDOWN

1

FUG

1

Description

Generac Emergency Generator (4SRB SI)

S/N: G9143001364 Install Date: 4/2014

(Used to provide back-up power)

Natural Gas-Fired Heater

(Used for comfort heating at the facility)

Vertical Fixed-Roof Storage Tank

(Used for storing lube oil for Turbines)

Vertical Fixed-Roof Storage Tank

(Used for storing oily wastewater / pipeline liquids)

Truck-Loading Point for Oil Wastewater

(used as a loading point to transfer liquid stored in the 100-bbl storage

tank to tanker trucks for off-site transport)

Compressor Blowdown Emissions from Turbine Shutdowns and

Startups for Maintenance

Fugitive Emissions

Size

Units

379.1

HP

2.51

MMBtu/hr

500

Gallon

100

bbl

N/A

N/A

N/A

N/A

N/A

N/A

e. Facility Construction and/or Permitting History

The La Plata A Compressor Station was acquired by Transwestern in 1996. At that time, the permitting

authority for the station was the Colorado Department of Public Health and Environment (CDPHE). The

station operated one turbine (T01) until 1997, when another turbine (T02) was added to the facility. Prior

to promulgation of Part 71 operating permits, federal air quality permits had not been required. However,

these sources were covered under CDPHE-issued Construction Permit Numbers 90-LP-050 and

subsequently 97-LP-0885 for T01 and 97-LP-0653 for T02. Transwestern submitted an initial Part 71

permit application on October 11, 1999. EPA issued an initial Part 71 permit (V-SU-0013-00.00) on

November 19, 2003. An application to renew this permit was submitted to EPA on January 14, 2008, and

the permit was renewed in June 2009 (V-SU-0013-08.00). In November 2009, EPA issued an

administrative amendment to the Part 71 permit (V-SU-0013-08.01). In January 2014, the Part 71 permit

(V-SU-0013-08.01) was replaced by the initial Part 70 permit, #V-SUIT-0013-2014.00. The Part 70

permit was revised and reissued as V-SUIT-0013-2014.01 in July 2014. On August 12, 2019, the permit

was renewed and issued as V-SUIT-0013-2019.00. A renewal permit, V-SUIT-0013-2023.00 was issued

on March 12, 2024.

f. Potential to Emit

Under RAC 1-103(51), potential to emit (PTE) is defined as the maximum capacity of a stationary source

to emit a pollutant under its physical and operational design. Any physical or operational limitation on

the capacity of the source to emit a pollutant, including air pollution control equipment and restrictions on

hours of operation or on the type or amount of material combusted, stored, or processed, shall be treated

as part of its design if the limitation, or the effect it would have on emissions, is federally enforceable.

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The PTE for La Plata A Compressor Station was listed by Transwestern in Forms “GIS”, “PTE”, and the

various forms “EMISS” of the Part 70 operating permit renewal application. Table 3 shows PTE data

broken down by each individual emission unit, as well as the total facility-wide PTE.

Emission

Unit ID

Table 3 - Potential to Emit

Transwestern Pipeline Company, La Plata A Compressor Station

Regulated Air Pollutants

in tpy

NOX

VOC

SO2

PM10

CO

Lead

Total

HAPs

Largest

Single HAP

(CH2O)

GHGs

(CO2e mtpy)

T01

64.5

0.42

0.69

1.3

16.5

0.0

0.19

0.14

21,403

T02

69.0

0.45

0.73

1.4

17.7

0.0

0.20

0.15

22,892

Total IEUs

0.67

2.9

0.0

0.0

1.0

0.0

0.0

0.03

1,261.5

134.2

3.8

1.4

2.7

35.2

0.0

0.4

0.3

45,557

2. Tribal Authority

La Plata A Compressor Station is located within the exterior boundaries of the Southern Ute Indian

Reservation and is thus within Indian Country as defined at 18 U.S.C. §1151. On March 2, 2012, the

EPA determined that the Southern Ute Indian Tribe of the Southern Ute Indian Reservation had met the

requirements of 40 CFR §70.4(b) for full approval to administer its Clean Air Act Title V, Part 70

Permitting Program (Program). In concert with that Program approval, the EPA also found that the Tribe

met the requirements of Section 301(d)(2) of the CAA and 40 CFR §49.6 for treatment “in the same

manner as a state” for the purposes of issuing CAA Title V, Part 70 operating permits. The EPA

promulgated its approval of the Tribe’s applications on March 15, 2012 (77 FR 15267). The

requirements of the Clean Air Act Title V, Part 70 Permitting Program (Program) have been incorporated

at Article II, Part 1 of the Reservation Air Code. Therefore, the Southern Ute Indian Tribe is the

appropriate governmental entity to issue the Title V permit to this facility.

Reservation Air Code: The Reservation Air Code was adopted pursuant to the authority vested in the

Southern Ute Indian Tribe/State of Colorado Environmental Commission by (1) the Intergovernmental

Agreement Between the Southern Ute Indian Tribe and the State of Colorado Concerning Air Quality

Control on the Southern Ute Indian Reservation dated December 13, 1999, (2) tribal law (Resolution of

the Council of the Southern Ute Indian Tribe No. 00-09), (3) State law (C.R.S. § 24- 62-101), and (4) as

recognized in federal law (Act of October 18, 2004, Pub. L. No. 108-336, 118 Stat.1354).

NSPS and NESHAP Delegation: On September 6, 2013, the Southern Ute Indian Tribe received

delegation from the EPA to incorporate by reference into the Reservation Air Code and enforce certain

subparts of the new source performance standards (NSPS) and national emission standards for hazardous

air pollutants (NESHAP) under Sections 111 and 112 of the Clean Air Act, respectively (78 FR 40635).

These NSPS and NESHAP subparts generally apply to oil and gas operations within the exterior

boundaries of the Southern Ute Indian Reservation and were adopted, unchanged, into the Reservation

Air Code as Parts 2 and 3.

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Tribal Minor New Source Review Program: Minor sources of air pollution located within the Southern

Ute Indian Reservation exterior boundaries must comply with either the “Federal Implementation Plan

for Managing Air Emissions from True Minor Sources in Indian Country in the Oil and Natural Gas

Production and Natural Gas Processing Segments of the Oil and Natural Gas Sector” listed at 40 CFR

§49.101 – 105 or the “Federal Minor New Source Review Program in Indian Country” listed at 40 CFR

§49.151 – 164.

3. Applicable Requirements

The following discussion addresses a selection of the regulations from the Code of Federal Regulations

(CFR) at Title 40. Note that this discussion does not include the full spectrum of potentially applicable

regulations and is not intended to represent official applicability determinations. These discussions are

based on the information provided by Transwestern in its Part 70 permit renewal application and are only

intended to present the information certified to be true and accurate by the Responsible Official of this

facility.

Prevention of Significant Deterioration (PSD) - 40 CFR 52.21

PSD is a preconstruction review requirement of the CAA that applies to proposed projects that are

sufficiently large (in terms of emissions) to be a “major” stationary source or “major” modification of an

existing stationary source. A new stationary source, or a modification to an existing minor stationary

source, is major if the proposed project has the potential to emit any pollutant regulated under the CAA

in amounts equal to or exceeding specified major source thresholds, which are 100 tpy for 28 listed

industrial source categories and 250 tpy for all other sources. PSD also applies to modifications at

existing major sources that cause a “significant net emissions increase” at that source. Significance

levels for each pollutant are defined in the PSD regulations at 40 CFR 52.21. A modification is a

physical change or change in the method of operation.

The La Plata A Compressor Station does not belong to any of the 28 listed source categories.

Therefore, the potential to emit threshold for determining PSD applicability for this source is 250

tpy. The La Plata A Compressor Station is a major source of NOx emissions, when aggregated

with La Plata B Compressor Station (owned by Northwest Pipeline GP, a subsidiary of Williams

Company), and the Ignacio Gas Plant (owned by Harvest Midstream, formerly owned by Williams

Company) for the purposes of PSD requirements. Northwest Pipeline is part owner of the La Plata

A Compressor Station, and therefore, under common control. In 1999, EPA made a single source

determination. The single source determination requires that the potential emissions from all

components at each source be aggregated when evaluating applicability of PSD. In addition,

emissions netting calculations must include emission increases and decreases from all three

sources.

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Periodic Monitoring

The Tribe may incorporate periodic monitoring requirements into a Part 70 permit when an applicable

requirement does not require sufficient periodic testing or instrumental or non-instrumental monitoring to

yield reliable data from the relevant time period that are representative of the source’s compliance with

the permit (RAC 2-110(5)(b)).

Periodic monitoring requirements have been incorporated into the Tribe’s Part 70 permit for the La Plata

A Compressor Station. The turbines at La Plata A Compressor Station are subject to the requirements of

40 CFR Part 60 Subpart GG. This subpart contains insufficient periodic monitoring requirements to

assure compliance with the applicable NOx limit for turbines in §60.332; only requiring a one-time

compliance test and no periodic monitoring. 40 CFR 60.334(c) provides the Tribe authority to allow

Transwestern to demonstrate compliance with the applicable NOx emission limit under §60.332 by using

a previously approved procedure for monitoring. Therefore, this permit includes the following periodic

monitoring:

1. The permittee shall measure NOX emissions from Units T01 and T02 at least once every quarter to

show compliance with the requirements of 40 CFR 60.332(a)(2). To meet this requirement, the

permittee shall measure the NOX emissions from the turbine using a portable analyzer and the

monitoring protocol approved by EPA, or by the monitoring protocols approved by EPA as

outlined in 40 CFR 60 Appendix A. Should the results of four consecutive quarterly portable

analyzer measurements be less than 75% of the NOx limit, the quarterly monitoring can be

reduced to semi-annual monitoring.

New Source Performance Standards (NSPS)

40 CFR Part 60, Subpart A: General Provisions. This subpart applies to the owner or operator of any

stationary source that contains an affected facility, the construction or modification of which is

commenced after the date of publication of any standard in Part 60. The general provisions under Subpart

A apply to sources that are subject to the specific subparts of Part 60.

As explained below, the La Plata A Compressor Station is subject to 40 CFR Part 60, Subpart GG

and Subpart JJJJ. Therefore, the General Provisions of Part 60 apply.

40 CFR Part 60, Subpart K: Standards of performance for Storage Vessels for Petroleum Liquids for

which Construction, Reconstruction, or Modification Commenced After June 11, 1973, and Prior to May

19, 1978. This rule applies to storage vessels for petroleum liquids with a storage capacity greater than

40,000 gallons. 40 CFR Part 60, Subpart K does not apply to storage vessels for petroleum or condensate

stored, processed, and/or treated at a drilling and production facility prior to custody transfer.

According to Transwestern, the La Plata A Compressor Station has no tanks with a storage

capacity greater than 40,000 gallons. Therefore, Subpart K does not apply.

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40 CFR Part 60, Subpart Ka: Standards of Performance for Storage Vessels for Petroleum Liquids for

which Construction, Reconstruction, or Modification Commenced After May 18, 1978, and Prior to

June 23, 1984. This rule applies to storage vessels for petroleum liquids with a storage capacity greater

than 40,000 gallons. Subpart Ka does not apply to petroleum storage vessels with a capacity of less than

420,000 gallons used for petroleum or condensate stored, processed, or treated prior to custody transfer.

According to Transwestern, the La Plata A Compressor Station has no tanks with a storage

capacity greater than 40,000 gallons. Therefore, Subpart Ka does not apply.

40 CFR Part 60, Subpart Kb: Standards of Performance for Volatile Organic Liquid Storage Vessels

(Including Petroleum Liquid Storage Vessels) for which Construction, Reconstruction, or Modification

Commenced After July 23, 1984. This rule applies to storage vessels with a capacity greater than or equal

to 75 cubic meters (~472 bbl).

According to Transwestern, the La Plata A Compressor Station has no tanks with a capacity

greater than or equal to 75 m3 (~472 bbl or 19,813 gal) that are used to store volatile organic

liquids. Therefore, Subpart Kb does not apply.

40 CFR Part 60, Subpart GG: Standards of Performance for Stationary Gas Turbines. This rule applies to

stationary gas turbines, with a heat input at peak load equal to or greater than 10.7 gigajoules per hour (10

MMBtu/hr), that commenced construction, modification, or reconstruction after October 3, 1977.

According to Transwestern, turbine units T01 and T02 were each constructed after October 3,

1977; each unit also has a heat input at peak load greater than 10 MMBtu/hr. Therefore, the

requirements of Subpart GG apply.

40 CFR Part 60, Subpart KKK: Standards of Performance for Equipment Leaks of VOC from Onshore

Natural Gas Processing Plants for which construction, reconstruction, or modification commenced after

January 20, 1984, and on or before August 23, 2011. This rule applies to compressors and other

equipment at onshore natural gas processing facilities. As defined in this subpart, a natural gas processing

plant is any processing site engaged in the extraction of natural gas liquids (NGLs) from field gas,

fractionation of mixed NGLs to natural gas products, or both. NGLs are defined as the hydrocarbons,

such as ethane, propane, butane, and pentane that are extracted from field gas.

According to Transwestern, the La Plata A Compressor Station does not extract natural gas liquids

from field gas, nor does it fractionate mixed NGLs to natural gas products, and thus does not meet

the definition of a natural gas processing plant under this subpart. Therefore, Subpart KKK does

not apply.

40 CFR Part 60, Subpart LLL: Standards of Performance for SO2 emissions from Onshore Natural Gas

Processing for which construction, reconstruction, or modification commenced after January 20, 1984,

and on or before August 23, 2011. This rule applies to sweetening units and sulfur recovery units at

onshore natural gas processing facilities. As defined in this subpart, sweetening units are process devices

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that separate hydrogen sulfide (H2S) and carbon dioxide (CO2) from a sour natural gas stream. Sulfur

recovery units are defined as process devices that recover sulfur from the acid gas (consisting of H2S and

CO2) removed by a sweetening unit.

According to Transwestern, the La Plata A Compressor Station does not perform sweetening or

sulfur recovery. Therefore, Subpart LLL does not apply.

40 CFR Part 60, Subpart JJJJ: Standards of Performance for Stationary Spark Ignition Internal

Combustion Engines. This subpart establishes emission standards and compliance requirements for the

control of emissions from emergency stationary spark ignition (SI) internal combustion engines (ICE) that

commenced construction, modification or reconstruction after January 1, 2009 and has a maximum engine

horsepower greater than 25.

For the purposes of this subpart, the date that construction commences is the date the engine is ordered by

the owner or operator (See 40 CFR 60.4230(a)).

Table 4 – NSPS Subpart JJJJ Applicability Determination

Transwestern Pipeline Company, La Plata A Compressor Station

Unit

Serial No.

Unit Description

BHP

GEN1

G9143001364

Generac SG250

379

Manufacture

Date

4/2014

Subpart JJJJ Trigger Date –

Manufactured on or after

January 1, 2009

According to Transwestern, emission unit GEN1, a Generac Emergency Generator (4SRB SI),

was manufactured after January 1, 2009 and has a maximum engine power greater than 25 hp.

Therefore, the requirements of Subpart JJJJ apply.

40 CFR Part 60, Subpart KKKK: Standards of Performance for Stationary Combustion Turbines. This

rule applies to stationary combustion turbines with a heat input at peak load equal to or greater than 10.7

gigajoules (10 MMBtu) per hour. This subpart establishes emission standards and compliance schedules

for the control of emissions from stationary combustion turbines that commenced construction,

modification, or reconstruction after February 18, 2005.

According to Transwestern, the turbines operating at La Plata A Compressor Station are affected

units under this subpart; however, the turbines were constructed prior to February 18, 2005 and

they have not been replaced or modified after February 18, 2005. Therefore, Subpart KKKK

does not apply

40 CFR Part 60, Subpart OOOO: Standards of Performance for Crude Oil and Natural Gas Production,

Transmission and Distribution. This subpart establishes emission standards and compliance schedules for

the control of VOC and SO2 emissions from affected facilities that commence construction, modification

or reconstruction after August 23, 2011. Affected facilities under this subpart include gas wells,

compressors, pneumatic controllers, storage vessels, process unit equipment, and sweetening units.

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According to Transwestern’s application, the La Plata A Compressor Station does not have any

affected facilities under the rule that commenced construction after August 23, 2011. Therefore,

Subpart OOOO does not apply.

40 CFR Part 60, Subpart OOOOa: Standards of Performance for Crude Oil and Natural Gas Facilities.

This subpart establishes emission standards and compliance schedules for the control of the pollutant

greenhouse gases (GHG) from affected facilities in the crude oil and natural gas source category that

commence construction, modification or reconstruction after September 18, 2015. Affected facilities

under this subpart include gas wells, compressors, pneumatic controllers, pneumatic pumps, storage

vessels, and the collection of fugitive emission components at well sites and compressor stations.

According to Transwestern, the La Plata A Compressor Station does not have any sources that

were constructed after September 18, 2015. Therefore, the facility is not subject to Subpart

OOOOa.

National Emission Standards for Hazardous Air Pollutants (NESHAP)

40 CFR Part 63, Subpart A: General Provisions. This subpart contains national emissions standards for

HAPs that regulate specific categories of sources that emit one or more HAP regulated pollutants under

the CAA. The general provisions under subpart A apply to sources that are subject to the specific

subparts of Part 63.

As explained below, the La Plata A Compressor Station is subject to 40 CFR Part 63 Subpart

ZZZZ. Therefore, the General Provisions of Part 63 apply as specified in the relevant

subparts.

40 CFR Part 63, Subpart HH: National Emission Standards for Hazardous Air Pollutants from Oil and

Natural Gas Production Facilities. This subpart applies to the owners and operators of affected units

located at natural gas production facilities that are area or major sources of HAPs, and that process,

upgrade, or store natural gas prior to the point of custody transfer, or that process, upgrade, or store

natural gas prior to the point at which natural gas enters the natural gas transmission and storage source

category or is delivered to a final end user. The affected units are glycol dehydration units, storage

vessels with the potential for flash emissions, and the group of ancillary equipment, and compressors

intended to operate in volatile hazardous air pollutant service, which are located at natural gas processing

plants.

Throughput Exemption

Those sources whose maximum natural gas throughput, as appropriately calculated per §63.760(a)(1)(i)

through (a)(1)(iii), is less than 18,400 standard cubic meters per day are exempt from the requirements of

this subpart.

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Source Aggregation

Major source, as used in this subpart, has the same meaning as in §63.2, except that:

1)

Emissions from any oil and gas production well with its associated equipment and emissions from

any pipeline compressor station or pump station shall not be aggregated with emissions from other

similar units.

2)

Emissions from processes, operations, or equipment that are not part of the same facility shall not

be aggregated.

3)

For facilities that are production field facilities, only HAP emissions from glycol dehydration units

and storage vessels with the potential for flash emissions shall be aggregated for a major source

determination.

Facility

For the purpose of a major source determination, facility means oil and natural gas production and

processing equipment that is located within the boundaries of an individual surface site as defined in

Subpart HH. Examples of facilities in the oil and natural gas production category include, but are not

limited to: well sites, satellite tank batteries, central tank batteries, a compressor station that transports

natural gas to a natural gas processing plant, and natural gas processing plants.

Production Field Facility

Production field facilities are those located prior to the point of custody transfer. The definition of

custody transfer (40 CFR 63.761) means the point of transfer after the processing/treating in the

producing operation, except for the case of a natural gas processing plant, in which case the point of

custody transfer is the inlet to the plant.

Natural Gas Processing Plant

A natural gas processing plant is defined in 40 CFR 63.761 as any processing site engaged in the

extraction of NGLs from field gas, or the fractionation of mixed NGLs to natural gas products, or a

combination of both. A treating plant or gas plant that does not engage in these activities is considered to

be a production field facility.

Major Source Determination for Production Field Facilities

The definition of major source in subpart HH (at 40 CFR 63.761) states, in part, that only emissions from

the dehydration units and storage vessels at production field facilities shall be aggregated when comparing

to the major source thresholds.

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For facilities that are not production field facilities, HAP emissions from all HAP emission units shall be

aggregated.

Area Source Applicability

40 CFR Part 63, Subpart HH also applies to area sources of HAPs. An area source is a HAP source

whose total HAP emissions are less than 10 tpy of any single HAP or 25 tpy for all HAPs in aggregate.

This subpart requires different emission reduction requirements for glycol dehydration units found at oil

and gas production facilities based on their geographical location.

Units located in densely populated areas (determined by the Bureau of Census) and known as urbanized

areas with an added 2-mile offset and urban clusters of 10,000 people or more, are required to have

emission controls. Units located outside these areas will be required to have the glycol recirculation

pump rate optimized or operators must document that uncontrolled annual actual benzene emissions are

less than 0.9 megagrams (1,984 lbs.).

Any source that determines that it is not a major source but has actual emissions of 5 tons per year of a

single HAP or 12.5 tons per year of a combination of HAP (i.e. 50 percent of the major source

thresholds), shall update its major source determination within 1 year of the prior determination and each

year thereafter, using gas composition data measured during the preceding 12 months.

Applicability of Subpart HH to the La Plata A Compressor Station

According to Transwestern, the La Plata A Compressor Station is not a production facility and

does not have any dehydration units; therefore, these requirements are not applicable. Therefore,

Subpart HH does not apply.

40 CFR Part 63, Subpart HHH: National Emission Standards for Hazardous Air Pollutants from Natural

Gas Transmission and Storage Facilities. This subpart applies to natural gas transmission and storage

facilities that transport or store natural gas prior to entering the pipeline to a local distribution company or

to a final end user, and that are a major source of hazardous air pollutant (HAP) emissions. Natural gas

transmission means the pipelines are used for long distance transport (excluding processing).

According to Transwestern, the La Plata A Compressor Station is a natural gas transmission

facility but does not have HAP emissions in excess of the major source thresholds of 10 tpy of a

single HAP or 25 tpy of HAPs in aggregate. Therefore, Subpart HHH does not apply.

40 CFR Part 63, Subpart YYYY: National Emission Standards for Hazardous Air Pollutants from

Stationary Combustion Turbines. This rule establishes national emission limitations and work practice

standards for HAPs emitted from stationary combustion turbines. An affected source includes any

stationary combustion turbine located at a major source of HAP emissions.

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Stationary Combustion Turbine:

Stationary combustion turbines are defined in §63.6175 as all equipment, including but not limited to the

turbine, the fuel, air, lubrication and exhaust gas systems, control systems (except emissions control

equipment), and any ancillary components and sub-components comprising any simple cycle stationary

combustion turbine, any regenerative/recuperative cycle stationary combustion turbine, the combustion

turbine portion of any stationary combined cycle steam/electric generating system. Stationary means that

the combustion turbine is not self-propelled or intended to be propelled while performing its function.

Stationary combustion turbines do not include turbines located at a research or laboratory facility, if

research is conducted on the turbine itself and the turbine is not being used to power other applications at

the research or laboratory facility.

Major Source:

Major Source for purposes of this subpart has the same meaning as provided in 40 CFR 63.2 with the

exception that emissions from any oil or gas exploration or production well (with its associated

equipment) and emissions from any pipeline compressor station or pump station shall not be aggregated

with emissions from other similar units, to determine whether such emission points or station are major

sources, even when emission points are in a contiguous are or under common control.

Applicability of Subpart YYYY to the La Plata A Compressor Station

The La Plata A Compressor station is not a major source of HAPs as determined from the

requirements of this rule. Therefore, Subpart YYYY does not apply

40 CFR Part 63, Subpart ZZZZ (RICE MACT): National Emission Standards for Hazardous Air

Pollutants for Stationary Reciprocating Internal Combustion Engines. This rule establishes national

emission limitations and operating limitations for HAPs emitted from stationary spark ignition internal

combustion engines (SI ICE) and stationary compression ignition internal combustion engines (CI ICE).

For the purposes of this standard, construction or reconstruction is as defined in §63.2.

Summary of Applicability to Engines at Major HAP Sources

Major HAP Sources

Engine Type

Horse Power Rating

New / Existing

Applicability Trigger Date

SI ICE – All1

≥ 500 HP

New

On or After:

12/19/2002

SI ICE – 4SRB

> 500 HP

Existing

Before:

12/19/2002

SI ICE – All1

≤ 500 HP

New

On or After:

6/12/2006

1

SI ICE – All

≤ 500 HP

Existing

Before:

6/12/2006

CI ICE – All2

≥ 500 HP

New

On or After:

12/19/2002

CI ICE – Non-Emergency

> 500 HP

Existing

Before:

12/19/2002

CI ICE – All2

≤ 500 HP

New

On or After:

6/12/2006

CI ICE – All2

≤ 500 HP

Existing

Before:

6/12/2006

1. All includes emergency ICE, limited use ICE, ICE that burn land fill or digester gas, 4SLB, 2SLB, and 4SRB.

2. All includes emergency ICE and limited use ICE

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Summary of Applicability to Engines at Area Hap Sources

Area HAP Sources

Engine Type

Horse Power Rating

New / Existing

Applicability Trigger Date

SI ICE – All

All HP

New

On or After:

6/12/2006

SI ICE – All1

All HP

Existing

Before:

6/12/2006

2

CI ICE – All

All HP

New

On or After:

6/12/2006

CI ICE – All2

All HP

Existing

Before:

6/12/2006

1. All includes emergency ICE, limited use ICE, ICE that burn land fill or digester gas, 4SLB, 2SLB, and 4SRB.

2. All includes emergency ICE and limited use ICE

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Table 5 – Applicability of 40 CFR 63, Subpart ZZZZ to the La Plata A Compressor Station:

Unit

Serial Number

Unit Description

Fuel

Site

Rated

HP

Commenced Construction,

Reconstruction, or

Modification Date

GEN1

G9143001364

Generac Emergency

Generator

Natural

Gas

379

After 06/12/2006

According to Transwestern, La Plata A Compressor station is an area source as defined in Subpart

ZZZZ. Unit GEN1 is an emergency generator engine < 500 HP constructed after June 12, 2006.

Therefore, GEN1 is considered a new emergency stationary RICE, and in accordance with

§63.6590(c), must meet the requirements of Subpart ZZZZ by meeting the requirements of

40 CFR Part 60 Subpart JJJJ. No further requirements of 40 CFR Part 63 Subpart ZZZZ

apply to GEN1.

40 CFR Part 63, Subpart DDDDD (Boiler MACT (for major sources)): National Emission Standards for

Hazardous Air Pollutants for Major Sources: Industrial, Commercial, and Institutional Boilers and

Process Heaters. This rule establishes national emission limitations and work practice standards for HAPs

emitted from new and existing industrial boilers, institutional boilers, commercial boilers, and process

heaters that are located at major sources of HAPs, as defined by 40 CFR 65.7575. Boilers or process

heaters that combust natural gas for fuel or have a maximum designed heat input capacity less than 10

MMBtu/hr are subject to work practice standards in lieu of emission limits. For the purposes of this

subpart, an affected unit is an existing unit if it was constructed prior to June 4, 2010.

According to Transwestern, the La Plata A Compressor Station is not a major source as defined in

this subpart. Therefore, Subpart DDDDD does not apply.

40 CFR Part 63, Subpart JJJJJJ (Boiler MACT (for area sources)): National Emission Standards for

Hazardous Air Pollutants for Area Sources: Industrial, Commercial, and Institutional Boilers. This rule

establishes national emission standards and operating limitations for HAPs emitted from new and existing

industrial boilers, institutional boilers, as defined in §63.11237, and commercial boilers that are fueled by

coal, biomass, or oil and are located at area sources of HAPs, as defined in §63.2, except for as specified

in §63.11195, as defined in §63.2, except for as specified in §63.11195. For the purposes of this subpart,

an affected unit is an existing unit if it was constructed prior to June 4, 2010.

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According to information provided by Transwestern in their application, there are no industrial,

commercial, or institutional boilers located at the La Plata A Compressor Station. Therefore,

Subpart JJJJJJ does not apply.

Compliance Assurance Monitoring (CAM) Rule

40 CFR Part 64: Compliance Assurance Monitoring Provisions. According to 40 CFR 64.2(a), the CAM

rule applies to each Pollutant Specific Emission Unit (PSEU) at a major source that is required to obtain a

Part 70 or Part 71 permit if the unit satisfies all of the following criteria:

1)

The unit is subject to an emission limitation or standard for the applicable regulated air pollutant

other than an emissions limitation or standard that is exempt under §64.2(b)(1);

Ҥ64.2(b)(1): Exempt emission limitations or standards. The requirements of this part shall not

apply to any of the following emission limitations or standards:

(i)

(ii)

(iii)

(iv)

(v)

(vi)

Emission limitations or standards proposed by the Administrator after November 15, 1990

pursuant to Section 111 or 112 of the Act;

Stratospheric ozone protection requirements under Title VI of the Act;

Acid Rain Program requirements pursuant to Sections 404, 405, 406, 407(a), 407(b) or

410 of the Act;

Emissions limitations or standards or other applicable requirements that apply solely

under an emissions trading program approved or promulgated by the Administrator under

the Act that allows for trading emissions with a source or between sources;

An emissions cap that meets the requirements specified in §70.4(b)(12) or §71.6(a)(13)(iii)

of this chapter;

Emission limitations or standards for which a Part 70 or 71 permit specifies a continuous

compliance determination method, as defined in §64.1.”

Ҥ64.1: Continuous compliance method means a method, specified by the applicable standard or

an applicable permit condition, which:

(1) Is used to determine compliance with an emission limitation or standard on a continuous

basis, consistent with the averaging period established for the emission limitation or standard;

and

(2) Provides data either in units of the standard or correlated directly with the compliance limit.”

2)

The unit uses a control device to achieve compliance with any such limit or standard; and

3)

The unit has pre-control device emissions of the applicable regulated pollutant that are equal to or

greater than 100% of the amount, in tons per year, required for a source to be classified as a major

source.

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According to Transwestern, the CAM rule does not apply to any of the units at the La Plata A

Compressor Station because neither of the PSEUs at the station use add on controls to achieve

emission limits, and the pre-controlled emissions for each unit are less than the major source

threshold. Therefore, CAM does not apply.

Chemical Accident Prevention Program

40 CFR Part 68: Chemical Accident Prevention Provisions. This rule applies to stationary sources that

manufacture, process, use, store, or otherwise handle more than the threshold quantity of a regulated

substance in a process. Regulated substances include 77 toxic and 63 flammable substances which are

potentially present in the natural gas stream entering the facility and in the storage vessels located at the

facility. The quantity of a regulated substance in a process is determined according to the procedures

presented under §68.115. §68.115(b)(l) and (2)(i) indicate that toxic and flammable substances in a

mixture do not need to be considered when determining whether more than a threshold quantity is present

at a stationary source if the concentration of the substance is below one percent by weight of the mixture.

§68.115(b)(2)(iii) indicates that prior to entry into a natural gas processing plant, regulated substances in

naturally occurring hydrocarbon mixtures need not be considered when determining whether more than a

threshold quantity is present at a stationary source. Naturally occurring hydrocarbon mixtures include

condensate, field gas, and produced water.

According to Transwestern, the La Plata A Compressor Station does not have regulated substances

above the threshold quantities in this rule. Therefore, the facility is not subject to the

requirement to develop and submit a risk management plan.

Stratospheric Ozone and Climate Protection

40 CFR Part 82, Subpart F: Air Conditioning Units. According to Transwestern, no maintenance,

service, repair or disposal of any equipment containing Class I or Class II refrigerants

chlorofluorocarbons (CFCs)) occurs at La Plata A Compressor Station. However, if Transwestern were to

engage in any of the afore mentioned activities it must comply with the standards of part 82, Subpart F for

recycling and emissions reduction if they service, maintain, or repair the air conditioning units in any way

or if they dispose of the units.

40 CFR Part 82, Subpart H: Halon Fire Extinguishers. According to Transwestern, there are no halon

fire extinguishers at La Plata A Compressor Station. However, should Transwestern obtain any halon fire

extinguishers, then it must comply with the standards of 40 CFR Part 82, Subpart H for halon emissions

reduction, if it services, maintains, tests, repairs, or disposes of equipment that contains halon or uses such

equipment during technician training. Specifically, Transwestern would be required to comply with 40

CFR Part 82 and submit an application for a modification to this Title V permit.

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Mandatory Greenhouse Gas Reporting

40 CFR Part 98: This rule requires sources above certain emission thresholds to calculate, monitor, and

report greenhouse gas emissions. The requirements of 40 CFR Part 98 and CAA §307(d)(1)(V), the CAA

authority under which 40 CFR Part 98 was promulgated, however, need not be included in a tribal-issued

Part 70 permit because those requirements are not included in the definition of “applicable requirement”

in either 40 CFR Part 70 or RAC 1-103(11). Although the rule is not an applicable requirement under 40

CFR Part 70 or the RAC, the source is not relieved from the requirement to comply with the rule

separately from compliance with its Part 70 operating permit. It is the responsibility of each source to

determine whether Part 98 is applicable and to comply, if necessary.

4. Public Participation

a. Public Notice

Per RAC §2-109, all Part 70 draft operating permits shall be publicly noticed and made available for

public comment. Public notice is given by publication in a newspaper of general circulation in the area

where the source is located or in a state publication designed to give general public notice, to persons on a

mailing list developed by the Tribe, including those who request in writing to be on the list, and by other

means if necessary to assure adequate notice to the affected public. If an interested person would like to

be added to the Tribe’s mailing list to be informed of future actions on permits issued by the Tribe, please

send your name and address:

by United States Postal Service to:

by any other delivery service to:

Part 70 Permitting Contact

Southern Ute Indian Tribe

Environmental Programs Department

PO Box 737 MS #84

Ignacio, Colorado 81137

Part 70 Permitting Contact

Southern Ute Indian Tribe

Environmental Programs Department

398 Ouray Drive

Ignacio, Colorado 81137

Public notice for the draft permit was published in the Durango Herald, and the Southern Ute Drum on

November 22, 2023 in order to provide opportunity for public comment on the draft permit and the

opportunity to request a public hearing.

b. Opportunity for Comment

Members of the public were given an opportunity to review a copy of the draft permit prepared by the

Tribe, the application, the statement of basis for the draft permit, and all supporting materials for the draft

permit. Copies of these documents were on the Southern Ute Air Quality Division webpage at

https://www.southernute-nsn.gov/government/departments/epd/air-quality/, and at:

16

Southern Ute Indian Tribe

Environmental Programs Department

Air Quality Division

71 Mike Frost Way

Ignacio, Colorado 81137

All documents were available for review at the Southern Ute Indian Tribe’s Environmental Programs

Department office Monday through Friday from 9:00 a.m. to 4:00 p.m. (excluding holidays).

Any interested person was given the opportunity to submit written comments on the draft Part 70

operating permit during the public comment period. The Tribe has considered and addressed comments

in making a final decision on the permit. The Tribe keeps a record of the commenters and of the issues

raised during the public participation process.

Anyone, including the applicant, who believed any condition of the draft permit was inappropriate, could

raise all reasonably ascertainable issues and submit all arguments supporting his or her position by the

close of the public comment period. Any supporting materials submitted must have been included in full

and may not have been incorporated by reference, unless the material had already been submitted as part

of the administrative record in the same proceeding or consisted of Environmental Commission, tribal,

state or Federal statutes and regulations, EPA documents of general applicability, or other generally

available reference material.

c. Opportunity to Request a Hearing

A person may submit a written request for a public hearing to the Part 70 Permit Contact at the addresses

listed above, by stating the nature of the issues to be raised at the public hearing. Based on the number of

hearing requests received, the Tribe will hold a public hearing whenever it finds there is a significant

degree of public interest in a draft operating permit. The Tribe will provide public notice of the public

hearing. If a public hearing is held, any person may submit oral or written statements and data concerning

the draft permit.

d. Public Petitions to the Administrator

In the event the Administrator of the United States Environmental Protection Agency does not object to

issuance of the permit, on the basis that it would not be in compliance with applicable requirements,

within its 45-day review period, any person may then petition the Administrator within 60 days after the

expiration of the Administrator’s 45-day review period to make such objection. Any such petition must

be based only on objections to the permit that were raised with reasonable specificity during the public

comment period unless the petitioner demonstrates that it was impracticable to raise such objections

within such period, or unless the grounds for such objections arose after such period. If the administrator

objects to a permit as a result of this petition, the Tribe shall not issue the permit until the Administrator’s

objection has been resolved, except that a petition for review does not stay the effectiveness of a permit or

17

its requirements if the permit was issued after the end of the 45-day review period and before the

Administrator’s objection.

e. Appeal of Permits

Within 60 days after the Tribe’s final permit action, an applicant, any person who filed comments on the

draft permit or participated in the public hearing, and any other person who could obtain judicial review

of that action under applicable law, may appeal to the Environmental Commission in accordance with

RAC 2-109(8) and the Commission’s Procedural Rules.

Petitions for administrative review of final permit actions can be filed after the deadline designated by the

Commission only if they are based solely on grounds arising after the deadline for administrative review

has passed. Such petitions shall be filed no later than 60 days after the new grounds for review arise. If

the final permit action being challenged is the Tribe’s failure to take final action, a petition for

administrative review may be filed any time before the Tribe denies or issues the final permit.

f. Notice to Affected States/Tribes

As described in RAC § 2-109(3), public notice will be given by notifying all affected programs.

The following entities will be notified:

•

•

•

•

•

•

•

State of Colorado, Department of Public Health and Environment

State of New Mexico, Environment Department

Ute Mountain Ute Tribe, Environmental Programs Department

Navajo Tribe, Navajo Nation EPA

Jicarilla Tribe, Environmental Protection Office

National Park Service, Air Resources Division, Denver, CO

U.S. Department of Agriculture, United States Forest Service, Rocky Mountain Region

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