PERMIT RATIONALE FOR REISSUANCE
Ergon Biofuels LLC
Warren County
Vicksburg, Mississippi
Water NPDES No. MS0060895
August 9, 2018

I.	FACILITY INFORMATION

Facility Name:  Ergon Biofuels LLC
Facility Address:  1833 Haining Road 
Vicksburg, MS  39183 
Permit No.:  MS0060895
SIC:  2869
Permit Writer:  Thomas Kelly
EPD Branch:  Water I

II.	NATURE OF BUSINESS

Produces fuel grade ethanol and DDGS as a byproduct.

III.	EFFLUENT AND RECEIVING STREAM FLOW DATA

Effluent from Outfall 001 consists of cooling tower blowdown. The outfall has a maximum daily flow of 0.08474 million gallons per day (MGD) and discharges into the Vicksburg Harbor Channel located in the Yazoo River Basin.  

IV.	303(d) or TMDL ISSUES

None.

V.	TYPE OF WASTEWATER TREATMENT:

None.

VI.	EPA APPLICABLE CATEGORICAL GUIDELINES

Since there is no process wastewater being discharged, there are no EPA applicable categorical guidelines.

VII.	STATE APPLICABLE GUIDELINES

The Mississippi environmental regulations have been renumbered and reformatted pursuant to the amended Administrative Procedures Act passed by the state legislature. While the numbering and citation of the regulations have changed, the content of the regulations have not.

1.	Mississippi Commission on Environmental Quality National Pollutant Discharge Elimination System (NPDES) Permits, Underground Injection Control (UIC) Permits, State Permits, Water Quality Based Effluent Limitations, and Water Quality Certification [11 Miss. Admin Code Pt. 6, Ch.1.]

2.	Mississippi Commission on Environmental Quality Regulations for Intrastate, Interstate, and Coastal Waters [11 Miss. Admin Code Pt. 6. Ch. 2]

VII.	DATA FROM APPLICATION FORM (2E and 2C)

Parameter	Maximum Daily Value	Long Term Average	
BOD	81.0 mg/L	13.98 mg/L	
TSS	36.0 mg/L	10.67 mg/L	
Fecal Coliform	N/A	N/A	
Total Residual Chlorine	N/A	N/A	
Oil and Grease	<1.05 mg/L	N/A	
COD	N/A	N/A	
TOC	8.53 mg/L	N/A	
Ammonia (as N)	2.60 mg/L	0.17 mg/L	
Flow	0.08474 MGD	0.07030 MGD	
pH	8.41 SU	7.78 SU	
Temperature (Winter)	20.4 °C	19.8 °C	
Temperature (Summer)	29.0 °C	28.0 °C	

VIII. 	WATER QUALITY LIMITATIONS BASED ON WASTELOAD ALLOCATION 

	None. 

IX.	CATEGORICAL GUIDELINE LIMITATIONS CALCULATIONS

Not Applicable

X.	TOXICITY SCREENING

Not Applicable
XI.	PROPOSED FINAL LIMITATIONS 

1.	Average Permit Limitations: lbs/day (mg/L)

Outfall	Parameter	Categorical Limitation	Water Quality Limitation	Present Permit Limitation	Proposed Permit Limitation	Basis	
001	NH3-N	N/A	N/A	10 (14)	10 (14)	Technical Judgment	
001	Flow 	N/A	N/A	Report MGD	Report MGD	Technical Judgment	
001	BOD5	N/A	N/A	19 (30)	19 (30)	Technical Judgment	
001	DO 	N/A	N/A	(6.0) min	(6.0) min	Technical Judgment	
001	pH	N/A	6.0 min. SU	6.0 min SU	6.0 min SU	WLA, 11 Miss. Admin
Code Pt. 6, Ch.1	
001	Temperature	N/A	--	Report °F min	Report °F min	Technical Judgment	
001	TSS	N/A	N/A	19 (30)	19 (30)	Technical Judgment	
001	TDS	N/A	N/A	Report (Report)	Report (Report)	Technical Judgment	

2.	Maximum Permit Limitations: lbs/day (mg/L)

Outfall	Parameter	Categorical Limitation	Water Quality Limitation	Present Permit Limitation	Proposed Permit Limitation	Basis	
001	NH3-N	N/A	N/A	15 (21)	15 (21)	Technical Judgment	
001	Flow 	N/A	N/A	Report MGD	Report MGD	Technical Judgment	
001	BOD5	N/A	N/A	28.5 (45)	28.5 (45)	Technical Judgment	
001	pH	N/A	9.0	9.0 SU	9.0 SU	WLA, 11 Miss. Admin
Code Pt. 6, Ch.1	
001	Temperature	N/A	90 °F max.	Report °F max	Report °F max	Technical Judgment	
001	TSS	N/A	N/A	28.5 (45)	28.5 (45)	Technical Judgment	
001	TDS	N/A	N/A	Report (Report)	Report (Report)	Technical Judgment	

MONITORING TYPE AND FREQUENCY

·  ”Flow” shall be monitored twice per month utilizing a totalizer and reported monthly basis.

•	“pH” shall be monitored twice per month utilizing grab sampling and reported monthly basis.

•	“Ammonia Nitrogen, Total (as N)” shall be monitored twice per month utilizing 24-hour composite sampling and reported monthly basis.

•	“Oxygen Demand biochemical, 5-day” shall be monitored twice per month utilizing 24-hour composite sampling and reported monthly basis.

•	“Oxygen, dissolved” shall be monitored twice per month utilizing grab sampling and reported monthly basis.

•	“Solids, (Total Dissolved) shall be monitored twice per month utilizing 24-hour composite sampling and reported monthly basis.

•	“Solids, (Total Suspended) shall be monitored twice per month utilizing 24-hour composite sampling and reported monthly basis.

•	“Temperature (Deg.F) shall be monitored twice per month utilizing instantaneous sampling and reported monthly basis.

XII.	BASIS FOR PROPOSED PERMIT LIMITATIONS:

Flow

The average and maximum flow limits of “Report” are based on technical judgment.

Total Suspended Solids (TSS):

The average and maximum concentration limitations of 30 mg/L and 45 mg/L, and the average and maximum mass limitations of 19 lb/day and 28.5 lb/day are based on technical judgment and were carried forward from the previous permit. 

Total Dissolved Solids (TDS):

The average and maximum effluent of “Report” are based on technical judgment and carried forward from the previous permit. 

Biochemical Oxygen Demand, 5-day (BOD5)

The average and maximum concentration limitations of 30 mg/L and 45 mg/L, and the average and maximum mass limitations of 19 lb/day and 28.5 lb/day are based on technical judgment and were carried forward from the previous permit. 

Dissolved Oxygen (DO)

The minimum concentration limit of 6 mg/L is based on technical judgment and carried forward from the previous permit.  

Total Ammonia Nitrogen (as N)

The average and maximum concentration limitations of 14 mg/L and 21 mg/L, and the average and maximum mass limitations of 10 lb/day and 15 lb/day are based on technical judgment and were carried forward from the previous permit. 

pH

The minimum and maximum pH effluent limits of 6.0 SU. and 9.0 SU are WQBELs that reflect the 11 Miss. Admin Code Pt. 6, Ch.2 requirement for the normal pH of waters shall be 6.0 to 9.0.  

Temperature (Deg. F)

The minimum and maximum Temperature effluent limits of “Report” are based on technical judgment and carried forward from the previous permit.