PERMIT REVIEW SUMMARY

Permit Writer:	Clinton Gentry 				Date:	January 21, 2026

Company Name:	Mississippi Lime Company-Vicksburg Plant

Facility Location:	1543 Haining Road
			Vicksburg, MS
	
			32° 23’ 29”
			90° 53’ 20”
			
Source Number:	2780-00014

County: 		Warren (39183)

FACILITY DESCRIPTION

Mississippi Lime Company’s (Mississippi Lime) Vicksburg Plant is a dry bulk lime processing facility located in Vicksburg, MS, classified under SIC Code 3274. The facility’s primary function is the receiving, processing, storage and distribution of lime and hydrated lime. While the facility has the capability to receive lime via barge, rail, or truck, the vast majority of intake is done via the facility’s Barge Receiving Hopper with Baghouse (Emission Point AA-001), Barge Belt Conveyor Transfer with Baghouse (Emission Point AA-002), and Barge Hopper Loadout (Emission Point AA-021).

PROJECT/PERMIT ACTION DESCRIPTION

Mississippi Lime has applied for a reissuance to their Synthetic Minor Operating Permit (SMOP). The facility has also requested that the following modifications be made:

•	For Emission Points AA-015A, AA-015B, and AA-016, Mississippi Lime requests that the throughput limits be removed from these emission points.

Emission Points AA-015A and AA-015B can receive lime via Emission Point AA-033. By limiting the throughput on AA-033, the downstream emission points will also share the same restriction. As such, a throughput limit on AA-015A and AA-015B is unnecessary. 

Emission Point AA-016 can only receive lime via truck loadout, and the maximum input capacity for the unit is very low, with very low associated emissions. The throughput limit may be removed on this emission unit, while still allowing the facility to remain under the Title V threshold.   

Emission Points AA-015A, AA-015B, and AA-016 route their emissions to baghouses for control. Mississippi Lime has not requested a change to the federally enforceable limitation that requires these emission points only be operated while their associated control device is also in operation. The maximum, controlled PM10 emissions from these three sources combined is 0.31 tpy.
 
•	Emission Points AA-025 and AA-031B were previously permitted as uncontrolled emission points. Mississippi Lime intends to install dust collection systems on these sources as included in an application to modify and has requested that they be included in the requirement to operate control devices while these emission points are being operated. 

•	For Emission Points AA-025 and AA-033, Mississippi Lime initially requested that the throughput limit on these emission points be removed. However, after discussions with the facility with alternative means of compliance, it was suggested that the throughputs be increased instead of being removed. Emission Point AA-025’s throughput has been increased to 657,000 tons/year and Emission Point AA-033’s throughput has been increased to 394,200 tons/year. These increased throughputs will still allow the facility to maintain their status as a synthetic minor source but will allow for more operational flexibility on lime receiving intake.

•	Mississippi Lime has requested that Emission Points AA-046 and AA-047 be added to the permit. These emission points would grant the facility the ability to load material from the slaking pad into trucks as a means to recycle material.

EMISSION SUMMARY

Criteria Pollutant	Maximum Uncontrolled	Potential Controlled	Title V Threshold	
Carbon Monoxide (CO)	6.43	7.87	100	
Nitrogen Oxides (NOx)	57.17	36.51	100	
Sulfur Dioxide (SO2)	2.22	2.25	100	
Particulate Matter 10 (PM10)	297.91	91.31	100	
Volatile Organic Compounds (VOC)	3.96	4.49	100	
Total Hazardous Air Pollutants (HAP)	0.01	0.01	25	

As shown in the table above, Mississippi Lime currently has the potential to exceed the Title V threshold for PM10 emissions. In order to qualify as a Synthetic Minor Source, Mississippi Lime elected to take a throughput limit to ensure that production levels keep emissions below the Title V threshold of 100 tpy for PM10. 

APPLICABLE/PROPOSED PERMIT LIMITATIONS

Emission Point No.	Pollutant	Draft Permit Emission Limits	Monitoring Requirements	
AA-001           AA-002           AA-004             AA-005               AA-021	Throughput (PM10)	< 500,000 tons/year	Maintain monthly throughput records	
AA-025		< 657,000 tons/year		
AA-033		< 394,200 tons/year		
AA-034		<100,000 tons/year		
AA-001            AA-002           AA-004               AA-005                   AA-006                  AA-007A              AA-008              AA-009              AA-011                 AA-012A               AA-012B                  AA-015A                   AA-015B               AA-016                   AA-017                      AA-018                 AA-019A                AA-019B                   AA-020A                     AA-020B             AA-021                   AA-025           AA-031D                  AA-031B                  AA-032	PM (Filterable Only)	Control equipment shall be operated at all times when emissions may be vented to it.	Record any time the control device is not operated when emissions are vented to it	
			Weekly inspections for visible emissions	
			Weekly maintenance inspections	
			Maintain records of each visible emissions inspection and maintenance inspections	

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

Subpart HH – Standards of Performance for Lime Manufacturing Plants
This subpart applies to each rotary lime kiln used in the manufacture of lime. This facility does not utilize a rotary lime kiln and is therefore not subject to this subpart.

Subpart IIII – Standards of Performance for Stationary Compression Ignition Internal Combustion Engines
This subpart applies to owners and operators of stationary Compression Ignition (CI) Internal Combustion Engines (ICE). Emission Point AA-040 is a 201.25 hp, 4-stroke, CI, diesel-fired emergency generator. Emission Point AA-042 is an 18.77 hp, 4-stroke, CI, diesel-fired emergency generator. Therefore, these engines are subject to this subpart and will show compliance with 40 CFR 63 Subpart ZZZZ by following all applicable conditions from this subpart.

MACT APPLICABILITY

Subpart ZZZZ – National Emissions Standards for Hazardous Air Pollutants for Stationary Reciprocating Internal Combustion Engines

This subpart applies to owners and operators of stationary Reciprocating Internal Combustion Engines (RICE) located at a major or area source of Hazardous Air Pollutants (HAPs). Emission Point AA-040 is a 201.15 hp diesel-fired emergency generator installed on site in 2019. Emission Point AA-042 is an 18.77 hp diesel-fired emergency generator installed on site in 2021. As such, these engines are subject to this subpart. However, according to 40 CFR 63.6590(c)(1), these emission points will demonstrate compliance with ZZZZ by meeting all requirements of 40 CFR  60 Subpart IIII. No further requirements from ZZZZ will apply.

PUBLIC PARTICIPATION

The 30-day public notice period began on February 4, 2026, when the notice was posted on MDEQ’s website and ends March 6, 2026.

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.