PERMIT RATIONALE FOR REISSUANCE
Stonewall POTW
Clarke County
Stonewall, Mississippi
Water NPDES No. MS0040151
June 2025

I.	CLASSIFICATION - Municipal Minor
II.	DESCRIPTION OF WASTEWATER – Domestic 
III.	DESCRIPTION OF WASTEWATER TREATMENT – Wastewater is biologically treated by means of a conventional lagoon followed by disinfection by chlorination thence dechlorination prior to discharge.  The current design capacity of the facility is 0.32 MGD.  
IV.	RECEIVING WATERS – Chickasawhay River.  The Chickasawhay River does not appear on the current State of Mississippi List of Impaired and Evaluated Waterbodies. This site is denoted in a Chickasawhay River TMDL for pathogens; the facility complies with the TMDL via disinfection. This waterbody is in the Pascagoula drainage basin. This portion of the Chickasawhay River is classified as Recreation.  
V.	APPLICABLE GUIDELINES
11 MS Admin Code pt. 6, Municipal Guidelines, 2025 Wasteload Allocation

VI.	SUMMARY AND BASIS OF DISCHARGE LIMITATIONS 
Parameter	Proposed Value	Basis	
Flow	0.32 MGD	Design	
BOD5	30 mg/l	WLA	
TSS	90 mg/l	Technology-Based	
e. Coli	126 Col./100 mL	WLA	
Chlorine, Total Residual	0.011 mg/l	Admin Code	
Dissolved oxygen, min	6.0 mg/l	WLA	
pH	6.0 to 9.0 S.U.	Admin Code	
BOD5, % Removal	65%	Municipal Guidelines	
TSS, % Removal	65%	Municipal Guidelines	
Total Nitrogen	Report	WLA	
Total Phosphorus	Report	WLA	
Total Ammonia Nitrogen	Report	WLA	

VII.	CHANGES FROM PREVIOUS PERMIT

Effluent monitoring for Total Ammonia Nitrogen has been added to the draft permit.