PERMIT RATIONALE FOR REISSUANCE
Pine Lake Estates Mobile Home Park
Lauderdale County
Meridian, Mississippi
Water NPDES No. MS0022641
February 2023

I.	CLASSIFICATION –NPDES Commercial

II.	DESCRIPTION OF WASTEWATER – Domestic

III.	DESCRIPTION OF WASTEWATER TREATMENT – Domestic wastewater is collected and treated via a conventional lagoon.  

IV.	RECEIVING WATERS – Unnamed Creek thence to Sowashee Creek. The receiving waters are located within the Pascagoula River Basin and are classified as Fish and Wildlife. Sowashee Creek does appear on the current 303(d) List of Impaired Waterbodies. The discharge is also included on a Total Maximum Daily Load (TMDL) on Sowashee Creek for Organic Enrichment/Low DO. One discharge is described within the application with no increase in flow proposed. The discharge from this existing facility should not further impair water quality standards. 

V.	APPLICABLE GUIDELINES – 11 Mississippi Admin Code pt. 6, Commercial Facility Guidelines (Technology), State of Mississippi Water Quality Criteria (MSWQS)

VI.	SUMMARY OF DISCHARGE LIMITATIONS – 

Parameter		Value					Basis
Flow			0.01 MGD				Design
Phase I	 BOD5		30 mg/l 				TMDL
Phase II BOD5		10 mg/l				WLA
Phase I NH3-N		Report, mg/l				WLA
Phase II NH3-N	1.37 mg/l				WLA
Phase I DO		Report, mg/l				WLA
Phase II DO		≥6.0 mg/l				WLA
TSS			90 mg/l 				Technology
E. Coli			126 Col./100mL 			WLA
pH			6.0 to 9.0 S.U.				WLA
Chlorine		0.1 to 1.0 mg/l				Technology
Total Nitrogen		Report, lbs./ day			WLA
Total Phosphorus	Report, lbs./ day			WLA

VII.	CHANGES FROM PREVIOUS PERMIT –

2023 Waste Load Allocation established new permit limitations for Ammonia, Dissolved Oxygen, BOD, Total Nitrogen, and Total Phosphorus.

The permittee shall achieve compliance with the effluent limitations specified for discharge in accordance with the following schedule:
Upon issuance of this permit, the permittee shall achieve compliance with the effluent limitations specified for the parameters without a phase designation and for the parameters noted as Phase I; Phase II limitations shall not apply at this time.

Beginning upon completion and start-up of improvements needed to comply with Phase II limitations or three (3) years after the issuance of the permit, whichever comes first, the permittee shall achieve compliance with the effluent limitations specified for the parameters without a phase designation and for the parameters noted as Phase II; Phase I limitations shall no longer apply at this time. 

The permittee shall notify our office orally at least 24 hours prior to start-up and in writing no later than 48 hours after start-up.

The Permittee shall Submit engineering report: Due once within 6 months (180 days) after effective date. Said report shall outline the improvement activities needed to upgrade the wastewater treatment facility to comply with the site's Phase II limitations and shall include a proposed schedule for those improvement activities.

The Permittee shall Submit progress report: Due annually - every 1 year after effective date. Said report shall update the Permittee's progress in addressing needed upgrades to the wastewater treatment facility in order to meet the site's Phase II limitations. Said report should also include an updated schedule for completing these activities.