PERMIT RATIONALE FOR REISSUANCE
Lucedale POTW
George County
Lucedale, Mississippi
Water NPDES No. MS0044504
September 2018

I.	CLASSIFICATION – NPDES Municipal Minor

II.	DESCRIPTION OF WASTEWATER – Municipal Wastewater

III.	DESCRIPTION OF WASTEWATER TREATMENT – Municipal wastewater is collected and treated via artificial wetlands followed by disinfection via gas chlorination prior to discharge. Only one discharge to surface waters is described in the application with no increase in treated effluent flow proposed. 

IV.	RECEIVING WATERS – Big Cedar Creek. The receiving waters are located in the Pascagoula River drainage basin and are classified as Fish and Wildlife. At the point of discharge, Big Cedar Creek does not appear on the current State of Mississippi 303(d) List of Impaired Waterbodies.  The discharge is included in a completed Total Maximum Daily Load (TMDL) for Mercury in the Pascagoula River (March 2005).  A Mercury Minimization Plan has been developed, which complies with the conditions of the TMDL. 

At the point of discharge, the 7Q10 for the receiving stream is 1.71 cfs.  The instream wastewater concentration at the point of discharge can be determined by the following calculation:

IWC = {(Qw)/(Qw + Qr)}*100

	Where, Qw = Design flow of the wastewater treatment facility, 0.5 MGD or 0.775 cfs
		 Qr = Receiving stream 7Q10, 1.71 cfs.

IWC = {(0.775 cfs)/(0.775 cfs + 1.71 cfs)}*100 = 31.18%

V.	APPLICABLE GUIDELINES – 11 Mississippi Admin Code pt. 6, Municipal Facility Guidelines (Technology), Wasteload Allocation (WLA)

VI.	CHANGES FROM PREVIOUS PERMIT – 

E. coli has replaced fecal coliform as the bacterial indicator for all freshwaters in Mississippi designated as Recreation, Fish and Wildlife Support, and/or Public Water supply. 

VII.	SUMMARY OF DISCHARGE LIMITATIONS – 
Parameter			Flow				Basis
Flow				0.5 MGD			Design
BOD5				30 mg/l			Technology
BOD (Percent Removal)	85% Minimum		Technology
Minimum DO			6 mg/l				WLA
TSS				30 mg/l			Technology
TSS (Percent Removal)	85% Minimum		Technology
	Ammonia Nitrogen			2 mg/l		WLA
E. coli				126 Col./100 ml		Admin Code	
Chlorine, Total Residual	0.03 mg/l			WLA
pH				6.0 – 9.0 SU			Admin Code