PERMIT REVIEW SUMMARY

Permit Writer:	Clinton Gentry 				Date:	March 11, 2025

Company Name:	Gulf South Pipeline Company LP, 
Black Creek Compressor Station

Facility Location:	4644 U S Highway 11, Purvis MS 39475
31°12' 22.82" N
89°20' 53.33" W

Source Number:	0800-00118

County: 		Forrest 

FACILITY DESCRIPTION

The Gulf South Pipeline Company, LP’s (Gulf South) Black Creek Compressor Station is a natural gas transmission site categorized under SIC Code 4922. This facility’s primary function is to supply natural gas to Cooperative Energy’s R.D. Morrow, Sr. Generating Plant located in Lamar County, Mississippi after the repowering project. The station may also supply gas to other customers in the area and will not be limited to exclusively serving Cooperative Energy. 

Gulf South has applied for a Synthetic Minor Operating Permit (SMOP) for the Black Creek Compressor Station. The facility was issued a permit to construct on April 29, 2020 with the station commencing startup on December 15, 2021. 

The facility has also requested that modifications be made to reflect equipment changes from what was originally anticipated during pre-construction planning. These changes include:

1)	For Emission Point AA-003, it was anticipated that a Caterpillar emergency generator rated at 637 horsepower (hp) would be installed. However, the final selection was a generator engine manufactured by Power Solutions, Inc. rated at 536 hp.  This will not trigger a change in the facility’s applicability to NSPS JJJJ or MACT ZZZZ, as both the proposed and actual engines fall under the same category of emergency engines with a maximum engine power greater than 25 hp manufactured after January 2009. 
2)	Emission Point AA-013 has been added to reflect the installation of a catalytic heater for gas, manufactured by Bruest Catalytic Heaters, rated at 0.104 MMBtu/hr. The emissions increase from the addition of this piece of equipment is negligible to the aggregate controlled emissions from the entire facility, with the largest being from Carbon Monoxide (CO) at 0.43 tons per year (tpy)
3)	Emission Points AA-014 and AA-015 have been added due facility’s need to have seven total storage tanks, up from the previously permitted five. Emission Point AA-014 is an 1,100-gallon tank used for maintenance lube oil storage. Emission Point AA-015 is an 1,100-gallon tank used oil storage.

EMISSION SUMMARY

Criteria Pollutant	Maximum Uncontrolled(1)	Title V Threshold	Exceed Threshold?	Potential Controlled	
Carbon Monoxide (CO)	107.23	100	Yes	8.45	
Nitrogen Oxides (NOx)	24.44	100	No	24.44	
Sulfur Dioxide (SO2)	0.09	100	No	0.09	
Particulate Matter 10 (PM10)	1.46	100	No	1.46	
Volatile Organic Compounds (VOC)	25.41	100	No	13.58	
Total Hazardous Air Pollutants (HAP)	13.74	25	No	3.44	
Individual HAPs(2)	11.10	10	Yes	2.78	
(1) All units are in tons per year (tpy)
(2) Formaldehyde is the largest, individual HAP

As shown in the table above, Gulf South has the potential to exceed the Title V threshold for both Carbon Monoxide (CO), as well as any individual HAP (In this case, Formaldehyde). 

APPLICABLE/PROPOSED PERMIT LIMITATIONS

In order to classify as an area Hazardous Air Pollutant (HAP) source, Gulf South must have individual HAP and total HAP emissions fall below 10 tpy and 25 tpy, respectively. Based on the potential, uncontrolled emissions listed in the table above, Gulf South’s formaldehyde emissions exceed the 10 tpy individual HAP threshold. To be classified as an area HAP source, Gulf South requests that the exhaust from the two compressor engines, as well as the emergency generator, be routed through the oxidation catalyst system whenever the units are in operation. This catalyst system will not only reduce HAP emissions but will also make it so that the Carbon Monoxide (CO) emission rate from these engines meets compliance with the CO emission rate required in 40 CFR 60, Subpart JJJJ. This emission limitation is 2.0 g/bhp-hr, with the engines being rated at 2.2 g/bhp-hr. As such, the facility is allowed to take into consideration the CO emissions limitation required by JJJJ in the uncontrolled emissions. This would take the Emissions of CO from 53.11 tpy per engine to 48.28 tpy per engine, resulting in a 9% allowable decrease. As such, Gulf South will be considered a minor source of emissions for CO but will be a potential major source of individual HAP emissions. 

40 CFR 60: NEW SOURCE PERFORMANCE STANDARDS (NSPS) APPLICABLITY

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 subpart applies to all vessels used for storing volatile organic liquids with a storage capacity greater than 19,800 gallons. All vessels at this facility will have capacities less than 19,800 gallons and are therefore not subject to this subpart.

Subpart JJJJ – Standards of Performance for Stationary Spark Ignition Internal Combustion Engines.
This subpart applies to owners and operators of Spark Ignition (SI) Internal Combustion Engines that have been modified, constructed, or reconstructed after June 12, 2006. Both compressor engines (Emission Points AA-001 & AA-002) will be manufactured after July 1, 2010 while the emergency generator engine (Emission Point AA-003) will be manufactured after January 1, 2009. Therefore, this facility is subject to this subpart. 

Subpart OOOOa – Standards of Performance for Crude Oil and Natural Gas Facilities for which Construction, Modification or Reconstruction Commenced After September 18, 2015.
This subpart applies to owners and operators of one or more of the onshore affected facilities for which construction, modification, or reconstruction commenced after September 18, 2015. This facility meets the definition of a “compressor station” and as such is subject to this subpart. This facility is also applicable to this subpart for the following components: continuous bleed natural gas-driven pneumatic controllers, reciprocating compressors, and all “fugitive emissions components”. The storage tanks located at this facility are not subject to this subpart due to their potential VOC emissions being less than 6 tpy. 

MACT APPLICABILITY

Subpart HHH – National Emissions Standards for Hazardous Air Pollutants from Natural Gas Transmission and Storage Facilities
This subpart applies to glycol dehydration units located at natural gas transmission or storage facilities that are major HAP sources. This facility will not be a major HAP source, nor will it contain any glycol dehydration units and therefore is not subject to this subpart.

Subpart ZZZZ – National Emission Standards for Hazardous Air Pollutants for Stationary Reciprocating Internal Combustion Engines
This subpart applies to owners and operators of Reciprocating Internal Combustion Engines (RICE) located at a major or area source of HAP emissions. As such, this facility is subject to this subpart. However, as per 63.6590(c)(1), these engines shall show compliance with this subpart by following all regulations specified in 40 CFR 60, Subpart JJJJ and no additional requirements from Subpart ZZZZ shall apply.

PUBLIC PARTICIPATION

The 30-day public notice period began on March 11, 2025, and ends April 10, 2025.

RECOMMENDATION

The staff has preliminarily decided to recommend issuance of the permit to the Mississippi Environmental Quality Permit Board as shown in the draft permit.  However, the staff recommendation to the Board will be made only after a thorough consideration of all public comments.