# Air Pollution Control (2026) > Briefs, arguments, decisions, and more. URL: https://www.frixlaw.com/law-library/documents/tribal%3Asouthern_ute%3A20b6a78ca7f47ef7 ## Record - **Collection:** Tribal code - **Document type:** Tribal code ## Text Air Pollution Control Title V Permit to Operate Statement of Basis for Permit No. V-SUIT-0002-2026.00 January 16, 2026 SIMCOE, LLC Treating Site #2 Compressor Station Southern Ute Indian Reservation La Plata County, Colorado 1. Facility Information a. Location The Treating Site #2 Compressor Station (Treating Site #2), owned and operated by SIMCOE, LLC (SIMCOE) is located within the exterior boundary of the Southern Ute Indian Reservation. The exact location is Section 20, T32N, R8W in La Plata County, at latitude North 37.008517 and longitude West -107.744849. The mailing address is: SIMCOE, LLC Treating Site #2 Compressor Station 1199 Main Ave, Suite 101 Durango, CO 81301 b. Contacts Facility Contact: Julie Best Senior Air Compliance Specialist SIMCOE, LLC 1199 Main Ave, Suite 101 Durango, CO 81301 (405) 862-5963 Responsible Official: Gavin Tweedie Midstream Superintendent SIMCOE, LLC 1199 Main Ave, Suite 101 Durango, CO 81301 (505) 320-3359 c. Description of Operations Treating Site #2 is a natural gas production field facility prior to the point of custody transfer. Fruitland coal bed methane wells feed into a gathering pipeline system leading to the inlet of this facility. The gas does not contain any condensate or natural gas liquids. The gas coalbed methane wells enters the facility and passes through a slug catcher used for water and gas separation. The water that drops out is stored in water tanks. Each water tank has a tank heater used during the winter months to heat the water. The produced water is transferred offsite for disposal. After leaving the slug catcher, the produced gas is compressed before passing through one glycol dehydrator unit equipped with natural gas fired reboilers to further dry the gas. The facility’s primary pollutant-emitting sources are two compressor engines, a generator engine, and a tri-ethylene glycol dehydrator. The engines are fueled by natural gas, and one the compressors utilizes lean burn technology while the other is equipped with catalytic reduction. Current production at this facility is 4 MMscfd. 1 d. List of all Units and Emission-Generating Activities SIMCOE 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. Table 1 - Emission Units SIMCOE, LLC – Treating Site #2 Compressor Station Emission Unit ID Control Equipment Description Waukesha L5790GSI 4SRB SI Compressor Engine 1,215 Nameplate Rated HP TS2-1 Serial No. 401231 Install Date: 08/09/2021 TS2-23 Serial No. 401236 Install Date: 01/28/2015 Waukesha L7042GL 4SLB SI Compressor Engine 1,478 Nameplate Rated HP TS2-9 Serial No. C10461/8 Install Date: None 08/26/2025 Caterpillar G3304NA 4SRB SI Generator Engine 95 Nameplate Rated HP TS2-13 Serial No. N4F01129 Install Date: None 09/2005 Tri-Ethylene Glycol (TEG) Dehydrator Regenerator Vent and Flash Tank Vent #1 20 MMscf/d TS2-8b TS2-8c Serial No. N/A Install Date: TS2-10b Serial No. N/A Install Date: None N/A Waukesha VRG 330 Generator Engine 68 Nameplate Rated HP TS2-3 2 Serial No. N/A Install Date: None N/A Tri-Ethylene Glycol Still Column Vent #2 20 MMscf/d 1 NSCR Catalyst and AFRC N/A Removed 1 TS2-10b has been disconnected from the process since 2015. This unit remains on site. TS2-3 has been shut down and permanently removed from the facility. However, this engine remains in the Part 70 permit as it is still listed in the PSD permit for this facility. 3 TS2-2 was removed from site in 2022. However, this engine remains in the Part 70 permit as it is still listed in the PSD permit for this facility. 2 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 2 minimis level established under Section 112(g), whichever is lower, for HAP emissions. However, the application may not omit information needed to determine the applicability of, or to impose, any applicable requirement, or to calculate the fee. 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. SIMCOE stated in its Part 70 permit renewal application the emission units in Table 2, below, are insignificant. The application provided calculations for fugitive emissions; heaters; tanks based on a combination of EPA’s Protocol for Equipment Leak Emission Estimates, Table 2-4, November 1995; manufacturer’s specifications, EPA’s AP-42 emission factors, and EPA Tanks 4.0.9d emission model. This data supports the source’s claim that these units qualify as insignificant. Table 2 - Insignificant Emission Units SIMCOE, LLC – Treating Site #2 Compressor Station Emission Unit ID Amount Description Size Units TS2-4, TS2-5 2 Tank Heaters 500 Mbtu/hr TS2-61 1 Glycol Reboiler 512 Mbtu/hr TS2-7 N/A Fugitive Sources N/A N/A TS2-8 1 Glycol Reboiler #1 350 Mbtu/hr TS2-11 1 Tank Heater 375 Mbtu/hr N/A 10 Catalytic Space Heaters 48 Mbtu/hr N/A 2 Catalytic Space Heaters 12 Mbtu/hr N/A 1 Catalytic Space Heater 18 Mbtu/hr N/A 1 Used Oil Tank 35 bbl N/A 3 Used Oil Sumps ≤ 90 bbl N/A 1 Tri-Ethylene Glycol (TEG) / Produced Water Dehy Sump 35 bbl N/A 1 Oily Water Tank 300 bbl N/A 2 Produced Water Tanks 500 bbl N/A 1 Produced Water Pit Tank N/A N/A N/A 1 Ethylene Glycol (EG) Tank 500 gal N/A 1 Lube Oil Tank 300 gal N/A 3 Lube Oil Tanks 500 gal N/A 1 Tri-Ethylene Glycol (TEG) Tank 500 gal 1 TS2-6 has been shut-down and permanently removed from the facility. However, this reboiler remains in the Part 70 permit as it is still listed in the PSD permit for this facility. e. Facility Construction and Permitting History DATE DESCRIPTION OF ACTION PERMIT NUMBER September 1999 Initial Part 71 Permit Issued # V-SU-0002-00.00 September 2007 1st Part 71 Renewal Permit Issued # V-SU-0002-05.00 January 2008 Administrative Amendment # V-SU-0002-05.01 January 2011 February 21, 2014 Administrative Amendment  Corrected serial number for TS2-13  Updated serial number and installation date for TS2-9  Modified permit language for clarification purposes Initial Part 70 Permit Issued Replaces EPA-issued permit: V-SU-0002-2005.02 3 # V-SU-0002-2005.02 # V-SUIT-0002-2014.00 February 4, 2020  December 30, 2020 January 16, 2026 1st Part 70 Renewal Permit Issued # V-SUIT-0002-2019.00 Administrative Revision Change of ownership from BP America Production Company to SIMCOE, LLC # V-SUIT-0002-2019.01 2nd Part 70 Renewal Permit Issued # V-SUIT-0002-2026.00 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. The PTE for Treating Site #2 was listed by SIMCOE 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. Table 3 - Potential to Emit SIMCOE, LLC – Treating Site #2 Compressor Station Regulated Air Pollutants in tpy Emission Unit ID Largest Single HAP (CH2O) GHGs (CO2 e tpy) NOx VOC SO2 PM10 CO Lead Total HAPs TS2-1 TS2-23 11.73 - 11.73 - 0.02 - 0.82 - 23.47 - 0.00 - 0.59 - 0.59 - 4,924.36 - TS2-9 TS2-13 TS2-8b & TS2-8c TS2-10b1 TS2-32 Total IEUs 19.13 16.49 0.00 0.96 12.76 0.78 99.63 1.22 0.78 0.00 0.00 0.01 0.41 0.05 0.00 0.07 38.27 1.25 0.00 0.81 0.00 0.00 0.00 0.00 3.70 0.15 0.00 0.00 3.70 0.15 0.00 0.00 4,844.17 317.16 6,194.93 10,000.87 TOTAL 48.31 126.12 0.81 1.35 63.80 0.00 4.44 4.44 26,281.49 Emission unit TS2-10b has been permanently disconnected since 2015. Therefore, this unit has no PTE. 2 TS2-3 has been shut down and permanently removed from the facility. However, this engine remains in the Part 70 permit as it is still listed in the PSD permit for this facility. 3 TS2-2 was removed from site in 2022. However, this engine remains in the Part 70 permit as it is still listed in the PSD permit for this facility. 1 2. Tribal Authority SIMCOE’s Treating Site #2 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 4 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. The 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. 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. These discussions are based on the information provided by SIMCOE 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. The following discussion does not include all potentially applicable regulations and is not intended to represent official Tribe applicability determinations. Tribal Minor New Source Review (TMNSR) – 40 CFR Part 49 EPA promulgated the federal rule “Review of New Sources and Modifications in Indian Country,” otherwise known as the Tribal Minor New Source Review Rule (TMNSR), on July 1, 2011 (76 FR 38748). The TMNSR rule applies to all new or modified industrial facilities in Indian country with a potential to emit equal to or greater than the minor NSR thresholds, but less than the major source thresholds, which are generally 100 to 250 tons per year (tpy). The minor NSR thresholds for attainment/unclassifiable areas are displayed in the table below: 40 CFR 49.153 Minor NSR Thresholds Minor NSR Thresholds for Regulated NSR Pollutant Attainment/Unclassifiable Areas in Tons Per Year (TPY) Carbon Monoxide (CO) 10 5 Nitrogen Oxides (NOx) Sulfur Dioxide (SO2) Volatile Organic Compounds (VOC) PM10 PM2.5 Lead Fluorides Sulfuric Acid Mist Hydrogen Sulfide (H2S) Total Reduced Sulfur (including H2S) Reduced Sulfur Compounds (including H2S) Municipal Waste Combustor Emissions Municipal Solid Waste Landfill Emissions (measured as nonmethane organic compounds) 10 10 5 5 3 0.1 1 2 2 2 2 10 10 On June 11, 2024, the Southern Ute Indian Tribe received partial delegation of the Tribal Minor New Source Review Program through the Agreement for Delegation of Partial Administrative Authority of Certain Federal Clean Air Act Indian Country Programs to the Southern Ute Indian Tribe by the United States Environmental Protection Agency. The two federal Clean Air Act (CAA) Programs are: (l) the Federal Implementation Plan for Managing Air Emissions from True Minor Sources in Indian Country in the Oil and Natural Gas Production and Oil and Natural Gas Processing Segments of the Oil and Natural Gas Sector (FIP), 40 Code of Federal Regulations (C.F.R.) Part 49, Subpart C, Sections 49.101 through 49.105 and (2) the Federal Minor New Source Review Program in Indian Country (MNSR), 40 C.F.R. Part 49, Subpart C, Sections 49.151 through 49.164. Under the FIP, all new and modified true minor oil and gas sources are required to register with the EPA to obtain coverage. Under the MNSR, minor sources and minor modifications at an existing source are required to obtain a preconstruction permit prior to beginning construction. The MNSR program provides a mechanism for a source to obtain authorization to construct through a site-specific permit or to accept federally enforceable requirements to become a “synthetic minor” source under NSR or the Title V permitting program. The program also includes general permits for six source categories. Future modifications at Treating Site #2 will be subject to the TMNSR rule; however, no TMNSR permits have been issued to this facility at this time. 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 considered a major stationary source or a major modification of an existing stationary source as defined in 40 CFR §52.21 (b)(1)(i) and (b)(2)(i). A new stationary source or a modification to an existing stationary source is major if the proposed project has the PTE any pollutant regulated under the CAA in amounts equal to or exceeding specified major source thresholds, which are 100 tpy for 28 listed industrial sources (named source) 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 (b)(23). A modification is a physical change or change in the method of operation. PSD applies to Treating Site #2. The original construction of the site, in 1990, triggered PSD Review. The operator was issued a PSD permit for Treating Site #2 on July 31, 1997. The PSD permit was revised on June 9, 1999. The PSD Permit requires that the subject engines meet an 6 emission limit of 1.0 g/hp-hr of NOx and 2.0 g/hp-hr of CO. These emission limits were accomplished by retrofitting the engines with non-selective catalytic reduction (NSCR) and air/fuel ratio controllers (AFRC). PSD Monitoring, Recordkeeping, and Reporting In addition to the emission limits, the PSD permit requires quarterly and semi-annual NO x and CO monitoring for controlled and uncontrolled engines, respectively. Portable analyzers were proposed by the operator for conducting monitoring. The PSD permit also requires that the operator keep records of its monitoring and maintenance information and that these records be kept for a period of 5 years. Monitoring data must be reported to EPA semi-annually. Periodic Monitoring The original Part 71 permit for Treating Site #2 included periodic monitoring requirements to supplement the PSD permit monitoring requirements for determining compliance with the NOx and CO engine emission limits for units TS2-1 and TS2-2. The monitoring requirements from the Part 71 permit have been incorporated into the Tribe’s Part 70 permit. However, upon processing the initial Part 70 permit application for Treating Site #2, the Tribe determined that units TS2-1 and TS2-2 were subject to 40 CFR Part 64, Compliance Assurance Monitoring (CAM). Therefore, in the Part 70 permit, a CAM plan was prepared by the operator and approved by the Tribe and was incorporated to replace the periodic monitoring requirements for units TS2-1 and TS2-2. 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, Treating Site #2 is not subject to specific subparts under 40 CFR part 60. Therefore, the General Provisions of Part 60 do not apply. 40 CFR Part 60, Subpart Db: Standards of Performance for Industrial-Commercial-Institutional Steam Generating Units. This rule applies to steam generating units with a heat input capacity of greater than 100 MMBtu/hr and commenced construction, modification, or reconstruction after June 19, 1984. According to SIMCOE, Treating Site #2 has no steam generating units with a heat input capacity greater than 100 MMBtu/hr at the facility. Therefore, Subpart Db does not apply. 40 CFR Part 60, Subpart Dc: Standards of Performance for Small Industrial-Commercial-Institutional Steam Generating Units. This rule applies to steam generating units with a maximum design heat capacity of 100 MMBtu/hr or less, but greater than or equal to 10 MMBtu/hr and commenced construction, modification, or reconstruction after June 9, 1989. According to SIMCOE, Treating Site #2 has no steam generating units with a maximum heat input capacity of 100 MMBtu/hr or less, but greater than or equal to 10 MMBtu/hr at the facility. Therefore, Subpart Dc does not apply. 7 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 SIMCOE, Treating Site #2 has no storage vessels for petroleum liquids for which construction, reconstruction, or modification commenced after June 11, 1973, and prior to May 19, 1978. Therefore, Subpart K does not apply. 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 July 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 SIMCOE, Treating Site #2 has no storage vessels for petroleum liquids for which construction, reconstruction, or modification commenced after May 18, 1978, and prior to July 23, 1984. 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, and On or Before October 4, 2023. This rule applies to storage vessels with a capacity greater than or equal to 75 cubic meters (472 bbl). According to SIMCOE, all tanks storing volatile organic liquids at Treating Site #2 are less than 75 m3 (472 bbl or 19,813 gal). 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 SIMCOE, there are no stationary gas turbines located at Treating Site #2. Therefore, Subpart GG does not 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 SIMCOE, Treating Site #2 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 SO 2 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 8 natural gas processing facilities. As defined in this subpart, sweetening units are process devices 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 H 2S and CO2) removed by a sweetening unit. According to SIMCOE, Treating Site #2 does not perform sweetening or sulfur recovery at the facility. Therefore, subpart LLL does not apply. 40 CFR Part 60, Subpart IIII: Standards of Performance for Stationary Compression Ignition Internal Combustion Engines. This subpart establishes emission standards and compliance requirements for the control of emissions from stationary combustion ignition (CI) internal combustion engines (ICE) that commence construction (which for the purposes of this subpart is the date the engine is ordered by the owner or operator) after July 11, 2005, and are manufactured as a certified National Fire Protection Association (NFPA) fire pump engine after July 1, 2006, or are manufactured after April 1, 2006, and are not fire pump engines. According to SIMCOE, there are no stationary compression ignition (CI) internal combustion engines (ICE) located at Treating Site #2. Therefore, Subpart IIII 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 stationary spark ignition (SI) internal combustion engines (ICE) that commenced construction, modification, or reconstruction after June 12, 2006, where the SI ICE are manufactured on or after specified manufacture trigger dates. The manufacture trigger dates are based on the engine type, fuel used, and maximum engine horsepower. 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)). SIMCOE provided the following information: Table 4 - NSPS Subpart JJJJ Applicability Determination SIMCOE, LLC – Treating Site #2 Compressor Station Unit Serial No. TS2-1 401231 TS2-9 C10461/8 TS2-13 N4F01129 Unit Description Waukesha L5790GSI 4SRB SI Compressor Engine Waukesha L7042GL 4SLB SI Compressor Engine Caterpillar G3304NA 4SRB SI Generator Engine Manufacture Date Commenced Construction Date Trigger Date for Applicability Manufactured on or after 1,215 07/31/1989 After 06/12/2006 07/01/2007 Natural Gas 1,478 02/21/1992 After 06/12/2006 07/01/2007 Natural Gas 95 12/08/2004 Prior to 06/12/2006 07/01/2008 Fuel Maximum HP Natural Gas 9 According to SIMCOE, units TS2-1 and TS2-9 were manufactured prior to July 1, 2007 (trigger date for engines with a maximum engine power greater than or equal to 500 hp). Unit TS2-13 was manufactured prior to July 1, 2008 (trigger date for engines with a maximum engine power less than 500 hp). None of the engines have been reconstructed or modified (as defined in §60.15) since June 12, 2006. Therefore, Subpart JJJJ does not apply. Should SIMCOE propose to install a replacement engine for Units TS2-1, TS2-9, and or TS2-13 that is subject to Subpart JJJJ, SIMCOE will not be allowed to use the off permit changes provision and will be required to submit a minor permit modification application to incorporate Subpart JJJJ requirements into the permit. 40 CFR Part 60, Subpart KKKK: Standards of Performance for Stationary Combustion Turbines. 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. The 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. According to SIMCOE, there are no stationary gas turbines located at Treating Site #2. 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, and on or before September 18, 2015. Affected facilities under this subpart include gas wells, compressors, pneumatic controllers, storage vessels, process unit equipment, and sweetening units. According to SIMCOE, Treating Site #2 does not include any affected facilities that have been constructed, modified, or reconstructed after August 23, 2011, and on or before September 18, 2015. Therefore, Subpart OOOO does not apply. Requirements of EPA’s Super-Emitter Program will not apply between July 31, 2025, and January 22, 2027. Super-Emitter Program provisions of this section will apply after January 22, 2027. 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). The greenhouse gas standard in this subpart is in the form of a limitation on emissions of methane from affected facilities in the crude oil and natural gas source category that commence construction, modification, or reconstruction after September 18, 2015. This subpart also establishes emission standards and compliance schedules for the control of volatile organic compounds (VOC) and sulfur dioxide (SO2) emissions from affected facilities in the crude oil and natural gas source category that commence construction, modification, or reconstruction after September 18, 2015, and on or before December 6, 2022. According to SIMCOE, Treating Site #2 does not include any affected facilities that have been constructed, modified, or reconstructed after September 18, 2015, and on or before December 6, 2022. Therefore, Subpart OOOOa does not apply. Requirements of EPA’s Super-Emitter Program will not apply between July 31, 2025, and January 22, 2027. Super-Emitter Program provisions of this section will apply after January 22, 2027. 10 40 CFR Part 60, Subpart OOOOb: 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). The greenhouse gas standard in this subpart is in the form of a limitation on emissions of methane from affected facilities in the crude oil and natural gas source category that commence construction, modification, or reconstruction after December 6, 2022. This subpart also establishes emission standards and compliance schedules for the control of volatile organic compounds (VOC) and sulfur dioxide (SO2) emissions from affected facilities in the crude oil and natural gas source category that commence construction, modification, or reconstruction after December 6, 2022. According to SIMCOE, Treating Site #2 does not include any affected facilities that have been constructed, modified, or reconstructed after December 6, 2022. Therefore, Subpart OOOOb does not apply. Requirements of EPA’s Super-Emitter Program will not apply between July 31, 2025, and January 22, 2027. Super-Emitter Program provisions of this section will apply after January 22, 2027. 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, Treating Site #2 is subject to specific subparts under 40 CFR part 63. Therefore, the General Provisions of Part 63 do apply. 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, as defined by §63.761, 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 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. 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 Central Delivery Point 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 11 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. 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 and a facility-wide actual annual average hydrocarbon liquid throughput less than 39,700 liters per day are exempt from the requirements of this subpart. 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. 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 applies also 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 Treating Site #2 Compressor Station According to SIMCOE, Treating Site #2 is located prior to the point of custody transfer and is therefore considered a production field facility and not a natural gas transmission or storage facility. Potential HAP emissions from the glycol dehydration unit and storage vessels at the facility are less than the major source thresholds of 25 tpy total HAPS and 10 tpy of a single HAP. Therefore, Treating Site #2 is considered an area source of HAPs according to 40 CFR part 63, subpart HH. Uncontrolled actual benzene emissions from the dehydration unit at the facility are less than 0.9 megagrams. Per 40 CFR 63.764(e)(1)(ii), the dehydration unit is exempt from the 40 CFR 63.764(d) 12 general standards for area sources. Therefore, only recordkeeping requirements apply to the facility. 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 SIMCOE, Treating Site #2 is a natural gas production facility and not a natural gas transmission or storage facility. Therefore, Subpart HHH does not apply. 40 CFR Part 63, Subpart ZZZZ (RICE MACT): National Emission Standards for Hazardous Air Pollutants for Stationary Reciprocating Internal Combustion Engines (RICE). This rule establishes national emission limitations and operating limitations for HAPs emitted from stationary spark ignition reciprocating internal combustion engines (SI RICE) and stationary compression ignition reciprocating internal combustion engines (CI RICE). 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 SI ICE - All1 ≤ 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. Summary of Applicability to Engines at Area Hap Sources Area HAP Sources Engine Type Horse Power Rating New / Existing Applicability Trigger Date 1 SI ICE - All All hp New On or After: 6/12/2006 SI ICE - All1 All hp Existing Before: 6/12/2006 CI ICE - All2 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. Applicability of 40 CFR 63, Subpart ZZZZ to Treating Site #2 Compressor Station: Unit Serial No. TS2-1 401231 TS2-9 C10461/8 Unit Description Fuel Waukesha L5790GSI Compressor Engine Waukesha L7042GL Compressor Engine Natural Gas Natural Gas 13 Site Rated HP Commenced Construction Date Subpart ZZZZ Trigger Date – Commenced Construction 1,200 After 06/12/2006 06/12/2006 1,321 After 06/12/2006 06/12/2006 TS2-13 N4F01129 Caterpillar G3304NA Generator Engine Natural Gas 81 Prior to 06/12/2006 06/12/2006 According to SIMCOE, Treating Site #2 is an area source of HAPs as defined in this subpart. Units TS2-1 and TS2-9 commenced construction after June 12, 2006, and are therefore considered new stationary RICE. Unit TS2-13 commenced construction prior to June 12, 2006, and is therefore considered an existing stationary RICE. Therefore, units TS2-1, TS2-9, and TS2-13 are subject to the applicable requirements of Subpart ZZZZ. 40 CFR Part 63, Subpart DDDDD (Boiler MACT): 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. 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 SIMCOE, Treating Site #2 is not a major source as defined in this subpart, or in 40 CFR Part 63, Subpart HH. Therefore, Subpart DDDDD does not apply. 40 CFR Part 63, Subpart JJJJJJ: 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, and commercial boilers, as defined in §63.11237 and are located at area sources of HAPs, as defined in § 63.2, except 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. According to SIMCOE, Treating Site #2 does not have any coal, oil, or biomass boilers at the facility. Therefore, 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); “§64.2(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) 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; 14 (iv) (v) (vi) 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.” “§64.1: 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. According to the information provided by SIMCOE, Treating Site #2 is a major source of NOx, and CO. Emissions units TS2-1 is a PSEUs with pre-controlled emissions that equal or exceed 100% of NOx and CO thresholds and use a control device to comply with an emission limitation. Therefore, units TS2-1 is subject to CAM requirements. 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. The regulations at §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. The regulations at §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. Based on SIMCOE’s application, Treating Site #2 does not have regulated substances above the threshold quantities in this rule. Therefore, Treating Site #2 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 SIMCOE’s application, there are no air conditioning units at Treating Site #2 that contain Class I or Class II refrigerants (chlorofluorocarbons (CFCs)). However, should SIMCOE obtain any air conditioning units at Treating Site #2 that contain Class 15 I or Class II refrigerants then 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 SIMCOE’s application, there are no halon fire extinguishers at Treating Site #2. However, should SIMCOE 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, SIMCOE would be required to comply with 40 CFR Part 82 and submit an application for a modification to this Title V permit. Mandatory Greenhouse Gas Reporting 40 CFR Part 98: Mandatory Greenhouse Gas Reporting. 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 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 State 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 October 31, 2025, in order to provide opportunity for public comment on the draft permit and the opportunity to request a public hearing. b. Opportunity for Comment 16 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/justice-and-regulatory/epd/air-quality/, and at: 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 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 17 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 18 --- Source: Frix Law Library, https://www.frixlaw.com/law-library/documents/tribal%3Asouthern_ute%3A20b6a78ca7f47ef7. Public record. Not legal advice.