PERMIT RATIONALE FOR REISSUANCE
Southern Natural Gas Company LLC, Rankin Compressor Station
Rankin County
Brandon, Mississippi
NPDES No. MS0051039
February 5, 2013

I.	FACILITY INFORMATION

Facility Name:  	Southern Natural Gas Company LLC, Rankin Compressor Station
Facility Address:  	191 Andrew Chapel Road 
	Brandon, MS  39439    
Houston, 
Permit No.:  		MS0051039
SIC:  			4922
Permit Writer:  	John Havard
EPD Branch:  		Energy and Transportation Branch

II.	NATURE OF BUSINESS

Natural gas compression for transport through the underground natural gas pipeline system.

III.	EFFLUENT AND RECEIVING STREAM FLOW DATA

The effluent is generated by two sources:  Storm water seepage from rain events collected in the basement sumps and condensate from the compressed air system.  The compressor station has three ways to handle the effluent: 
1.	Discharge to an unnamed tributary of Richland Creek
2.	Evaporation by using the on-site evaporator
3.	Hauled off-site for disposal
	The unnamed tributary has a 7Q10 of 0 MGD.  The facility generates a maximum of                      0.00004 Million gallons per day of effluent. 

IV.	303(d) ISSUES

This section of the Pearl River Basin was not listed on the 2012 303(d) list.  A TMDL was approved for this section of Richland Creek on December 18, 2009 to alleviate organic enrichment, low dissolved oxygen, and nutrients.  This outfall was not listed due to no discharge from the facility since the fourth quarter of 1999.

V.	TYPE OF WASTEWATER TREATMENT:

The waste water is evaporated or hauled off-site for disposal. 

VI.	EPA APPLICABLE CATEGORICAL GUIDELINES

None

VII.	DATA FROM APPLICATION FORM 2C: Since the facility does not currently discharge, 
                                                                                   the application data was from the November                                                                                2000 application.

Parameter	Maximum Daily Value	
Biochemical Oxygen Demand	34.0 mg/l	
Chemical Oxygen Demand	130.0 mg/l	
Total Organic Carbon	10.7 mg/l	
Total Suspended Solids	230.0 mg/l	
Ammonia (as N)	<0.02 mg/l	
Flow	0.00004	
Winter Temperature	4.5 o C	
Summer Temperature	27.0 o C	
pH	8.41 su	
Oil and Grease	18 mg/l	
Surfactants	0.14 mg/l	
PCB 1016	<0.5 ug/l	
PCB 1221	<0.5 ug/l	
PCB 1232	<0.5 ug/l	
PCB 1242	<0.5 ug/l	
PCB 1248	<0.5 ug/l	
PCB 1254	<1.0 ug/l	
PCB 1260	<1.0 ug/l	

VIII. 	WATER QUALITY LIMITATIONS BASED ON WASTELOAD ALLOCATION 

	Not Applicable 

IX.	CATEGORICAL GUIDELINE LIMITATIONS CALCULATIONS

Not Applicable

X.	TOXICITY SCREENING

Not Applicable

XI.	PROPOSED FINAL LIMITATIONS FOR OUTFALL MS0051039-001 

1.	Maximum Permit Limitations

Parameter	Present Permit Limitation	Proposed Permit Limitation	Basis	Monitoring Frequency	Sample Type	
Flow	Report	Report	BTJ	Once/ Month	Instantaneous	
TSS	45 mg/l	45 mg/l	BTJ	Once/ Month	Grab	
pH	9.0 su	9.0su	State Limit	Once/ Month	Grab	
Oil and Grease	15 mg/l	15 mg/l	BTJ	Once/ Month	Grab	
BOD5	Report	Report	BTJ	Once/ Month	Grab	
PCB 1016	0.000045 ug/l	0.000045 ug/l	BTJ 	Once/ Year	Grab	
PCB 1221	0.000045 ug/l	0.000045 ug/l	BTJ	Once/ Year	Grab	
PCB 1232	0.000045 ug/l	0.000045 ug/l	BTJ	Once/ Year	Grab	
PCB 1242	0.000045 ug/l	0.000045 ug/l	BTJ	Once/ Year	Grab	
PCB 1248	0.000045 ug/l	0.000045 ug/l	BTJ	Once/ Year	Grab	
PCB 1254	0.000045 ug/l	0.000045 ug/l	BTJ	Once/ Year	Grab	
PCB 1260	0.000045 ug/l	0.000045 ug/l	BTJ	Once/ Year	Grab	

2.	Average Permit Limitations

Parameter	Present Permit Limitation	Proposed Permit Limitation	Basis	Monitoring Frequency	Sample Type	
Flow	Report	Report	BTJ	Once/Month	Instantaneous	
TSS	30	30	BTJ	Once/Month	Grab	
Oil and Grease	10 mg/l	10 mg/l	BTJ	Once/Month	Grab	
pH, Minimum	6.0 su	6.0 su	State Limit	Once/Month	Grab	
BOD5	Report	Report	BTJ	Once/Month	Grab	

This facility has not discharged wastewater since the fourth quarter of 1999.  The requirement to complete a Form 2C application within 180 days of a discharge will remain in the permit to allow the permit to be reopened if the above limitations need to be modified. 
The PCB maximums are based using the human health criteria for total PCBs with an equal limit given to each individual PCB.

XII.	BPJ STATEMENT: 

It is our Best Technical Judgment that the foregoing limitations represent adequate limits to protect waters of the State.