INFORMATION RELATIVE TO 
THE DRAFT TITLE V OPERATING PERMIT
May 18, 2026

GENERAL FACILITY INFORMATION
Facility Name:  Southern Natural Gas Company LLC, Rankin Compressor Station
Facility Address:  
191 Andrew Chapel Road
Brandon, MS 39439    
County: Rankin
SIC Code(s): 4922
NAICS Code(s): 486210  

APPLICATION SUMMARY 
Permit No.: 2380-00083
Permit Action:  Renewal
Permit Folder: PER20260001
Application Receipt Date: 03/04/2026
Application Deemed Complete: May 18, 2026
CBI Submitted?: No	NSPS (Part 60): N/A
NESHAP (Part 61): N/A
NESHAP (Part 63): Subparts A, ZZZZ, DDDDD
112(r) / RMP: N.A
Other: N/A	

FACILITY DESCRIPTION
Southern Natural Gas Company owns and operates its Rankin Compressor Station located at 191 Andrew Chapel Road, in Brandon, Mississippi (Rankin County) for the purpose of transporting natural gas through its pipeline distribution system. Natural gas compression at the Rankin Compressor Station is accomplished through three (3) 1,350-HP-each natural gas-fired Cooper Bessemer compressor engines.  The station also operates one (1) 225-HP natural gas-fired emergency generator engine and one (1) 1.0 MMBTU/hr natural gas fired process boiler.  Other sources of emissions include fugitive emissions from piping and equipment and emissions from insignificant activities.

TITLE V SOURCE APPLICABILITY 
The facility’s potential-to-emit (PTE) exceeds the Title V major source threshold of 100 tons per year (tpy) for the criteria air pollutant: Nitrogen Oxides (NOX).  The facility’s potential-to-emit hazardous air pollutants (HAPs) does not exceed the major source threshold of 25 tpy of total HAPs and but it does exceed the Title V Major Source threshold of 10 tpy for the individual HAP Formaldehyde. 

Facility-Wide Potential-to-Emit Summary1
Pollutant	PTE Emissions
(tons/yr)	
Particulate Matter (TSP)	7.23	
PM10	9.11	
PM2.5	9.11	
Sulfur Dioxide (SO2)	0.12	
Nitrogen Oxides (NOx)	634.86	
Carbon Monoxide (CO)	33.54	
Volatile Organic Compounds (VOC)	35.87	
CO2e	28,682.51	
Total HAP 	16.85	
Individual HAP - Formaldehyde	10.36	
1 The PTE emissions reflect any emission limits or enforceable restrictions included in the proposed permit.

PREVENTION OF SIGNIFICANT DETERIORATION (PSD) APPLICABILITY
The facility is not one of the 28 categorical facilities listed in 40 CFR 52.21(b)(1)(i)(c)(iii); therefore, the PSD threshold for a major source is 250 tpy.  The potential emissions of NOx from the equipment at the compressor station does exceed 250 tpy. Therefore, the facility is considered an existing major source for PSD purposes.  The permit action is to renew the Title V permit which will not trigger a Prevention of Significant Deterioration (PSD) Review.

FACILITY MODIFICATIONS AND/OR PERMIT CHANGES
On March 4, 2025, SNG submitted a request for a 502(b)(10) modification for the replacement of a 0.8 MMBtu/hr Cleaver Brooks natural gas-fired boiler (Emission Point AA-007) with a 1.0 MMBtu/hr Cleaver Brooks (Model CFC-E) natural gas-fired boiler (Emission Point AA-009). This replacement boiler does not significantly increase overall site emission totals and is subject to the same requirements as the previous boiler. 

COMPLIANCE ASSURANCE MONITORING (CAM) APPLICABILITY
40 CFR Part 64 specifies the requirements for CAM.  The general applicability of this rule can be found in 40 CFR 64.2 and requires a Title V source to comply with the CAM requirements if all three of the following criteria are met for a pollutant-specific emission unit (PSEU):

1.	The unit is subject to an emission limitation or standard for a regulated air pollutant other than exemptions under 40 CFR 64.2(b)(1);
2.	The unit uses a control device to comply with the standard; and
3.	The unit has pre-control emissions exceeding Title V major source threshold.

There is no control equipment associated with any emission units subject to an emission limit or standard at this facility, so Compliance Assurance Monitoring does not apply.

NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS (NESHAP) APPLICABILITY
The facility is a major source of Hazardous Air Pollutants (HAP) since the facility has the potential to emit more than 10 tpy of the individual HAP Formaldehyde. 

40 CFR 63, Subpart ZZZZ
The permittee is subject to Subpart ZZZZ—National Emissions Standards for Hazardous Air Pollutants for Stationary Reciprocating Internal Combustion Engines, and shall comply with all applicable requirements.  The Reciprocating Internal Combustion Engines (RICE) NESHAP, Subpart ZZZZ, regulates HAP emissions from RICE. 

Emission Points AA-001, AA-002, and AA-003 are existing non-emergency spark ignition two stroke lean burn (2SLB) stationary RICE, each with a site rating greater than 500 brake HP located at a major source of HAP emissions and as such have no applicable requirements of 40 CFR 63, Subpart ZZZZ, or the General Provisions of 40 CFR 63, Subpart A. 

Emission Point AA-006 is an existing emergency spark ignition four stroke rich burn (4SRB) stationary RICE with a site rating of less than 500 brake HP located at a major source of HAP emissions and as such is subject to the scheduled maintenance activities and operational requirements of 40 CFR 63, Subpart ZZZZ.

40 CFR 63, Subpart DDDDD
The permittee is subject to Subpart DDDDD— National Emission Standards for Hazardous Air Pollutants for Industrial, Commercial, and Institutional Boilers and Process Heaters, and shall comply with all applicable requirements.  

Emission Point AA-009 is a new small boiler in the “units designed to burn gas 1 fuel” subcategory as listed in 40 CFR 63.7499(l) and defined in 40 CFR 63.7575. This unit does not have any applicable emission standards and has to comply with the requirement to perform a tune-up every 5-years, recordkeeping and submittal requirements.

NEW SOURCE PERFORMANCE STANDARDS (NSPS) APPLICABILITY
The facility is not currently subject to any New Source Performance Standards.

40 CFR 60, Subpart Dc—Standards of Performance for Small Industrial-Commercial-Institutional Steam Generating Units
This standard is applicable to each steam generating unit for which construction, modification, or reconstruction is commenced after June 9, 1989, and that has a maximum design heat input capacity of 29 MW (100 MMBtu/hour) or less, but greater than or equal to 2.9 MW (10 MMBtu/hour). 
The facility operates a single 1 MMBtu/hr boiler (Emission Point AA-009), but the maximum design heat input capacity is not greater than or equal to 10 MMBtu/hour, and therefore, is not subject to NSPS Subpart Dc.

SPECIFIC APPLICABLE REQUIREMENTS
The five (5) significant air emission combustion sources are subject to state standards for PM and Opacity. Emission Points AA-006 and AA-009 have a particulate matter emission limitation of 0.6 lbs/MMBTU, because the units have a rated heat input less than 10 MMBTU/hr. Emission Points AA-001, AA-002, and AA-003 each have a rated heat input greater than 10 MMBTU/hr and thus are subject to a particulate matter limit of E=0.8808 * I-0.1667 where E is the emission rate in pounds per million BTU per hour heat input and I is the heat input in millions of BTU per hour.  Emission Point AA-009 has a sulfur dioxide emission limitation of 4.8 lbs/MMBTU.  

The facility’s small space heaters qualify as insignificant activities.  These activities are subject to the state standards for PM, SO2 and Opacity.  Since these units combust natural gas and the size of the units are small, no monitoring is proposed for the units.  There are no other applicable requirements for the facility’s other insignificant activities listed in their Title V application.

Emission Point No.	Pollutant	Draft Permit Emission Limits	Monitoring Requirements	
AA-001,
AA-002, and
AA-003	PM	E = 0.8808 * I -0.1667	Record Type and Quantify of Fuel Used	
AA-006 and
AA-009	PM	0.6 lb/MMBTU	Record Type and Quantify of Fuel Used	
AA-006	HAPs	Emergency Operations	Operational Requirement	
	HAPs	Scheduled Maintenance Activities and General Operating Requirements	Operational Requirement	
AA-009	SO2	4.8 lb/MMBTU	Record Type and Quantify of Fuel Used	
	HAPs	Conduct tune-ups every 5 years	Operational Requirement	

OTHER REQUIREMENTS:
N/A