PERMIT RATIONALE FOR REISSUANCE
Nouryon Pulp and Performance Chemicals LLC
Lowndes County
Columbus, Mississippi
Water NPDES No. MS0040215
November 2025

I.	FACILITY INFORMATION

Facility Name:  Nouryon Pulp and Performance Chemicals LLC
Facility Address:  4374 Nashville Ferry Road East 
Columbus, MS  39702    
Columbus, 
Permit No.:  MS0040215
SIC:  2819
Permit Writer:  Samar Patel
Branch:  Water I Branch

II.	NATURE OF BUSINESS

Nouryon Pulp and Performance Chemicals LLC (Nouryon) is a manufacturer of inorganic chemicals.  This facility produces sodium chlorate and hydrogen peroxide. 

III.	EFFLUENT AND RECEIVING STREAM FLOW DATA

The facility has applied for a re-issuance of the facility’s existing NPDES permit comprised of the following outfalls: 

Outfall 104 (Internal outfall for Hydrogen Peroxide Process) – This is an internal outfall receiving wastewater from the Hydrogen Peroxide process.  This outfall includes wastewaters from production of hydrogen perioxide, carbon filter wash waters, and reverse osmosis reject waters from the deionization backwash.  The purpose of the separate outfall is to adequately monitor the process wastewater, which is subject to categorical standards.  The long-term average (LTA) flow is 0.0651 MGD and discharges to Outfall 001. 

Outfall 001 – Comprised of wastewaters from the plant site, which includes: wastewaters generated from chlorate production, boiler blowdown, air compressor cooling water, brine plant wastewaters, cooling tower blowdown, wastewater from internal outfall 104, storm waters, and treated sanitary effluent.  LTA flow is 0.521 MGD and discharges to the Tennessee-Tombigbee Waterway in the Tombigbee Basin (7Q10 = 337 cfs = 217.81 MGD).  Designated use classification: Fish & Wildlife.

1 LTA flow listed herein is based on DMR data from year 2021-2023

IV.	303(d) ISSUES

There are no 303(d) issues for this site.  In October 2008, a TMDL for organic enrichment and dissolved oxygen was finalized by EPA for Tombigbee River (Aliceville Reservoir). Nouryon is subject to this TMDL and the limits found in the permit are consistent with the limitations found in the TMDL.  

V.	TYPE OF WASTEWATER TREATMENT:

A.	Outfall 104 (Internal outfall for Hydrogen Peroxide Process) – Wastewater treatment methods include carbon adsorption, decomposition, and flotation thickening

B.	Outfall 001 – Wastewater treatment methods for Sanitary Units 1 and 2 wastewater are chlorination and aerobic treatment units, the C85/89 Cooling Towers wastewater receive chlorination, sand bed filtering and settling, and the Salt Evaporator wastewater is treated via neutralization.

VI.	EPA APPLICABLE CATEGORICAL GUIDELINES

A.	Outfall 104 (Internal outfall for Hydrogen Peroxide Process)

In past, the facility is erroneously made subject to 40 CFR Part 415 – Inorganic Chemicals Manufacturing Point Source Category, Subpart I – Hydrogen Peroxide Production Subcategory. This subpart applies to the facilities that produce hydrogen peroxide either by the electrolytic process or by the oxidation of alkyl hydroanthraquinones.  Since at Nouryon, hydrogen peroxide is manufactured by direct oxidation over a palladium catalyst and as such processes as referenced under the Subpart are not used at the facility, they are not subject to this subpart. 

B.	Outfall 001

40 CFR Part 415 – Inorganic Chemicals Manufacturing Point Source Category, Subpart BN – Sodium Chlorate Production Subcategory. 

VII.	DATA FROM APPLICATION FORM (Enter the type of application, i.e. 2D)

A.	Outfall 104 (Internal outfall for Hydrogen Peroxide Process)

Table 1 – Intake and Effluent Characteristics for Outfall 104
Parameter	Maximum Daily Value*	Long Term Average Value*	No. of Analysis	
Flow	0.143 MGD	0.065 MGD	Continuous	
TOC	75.37 lbs/day	6.30 lbs/day	36	
TSS	9.90 lbs/day	1.14 lbs/day	36	
pH	8.50 s.u. (max.)	6.0 s.u. (min.)	36	

* The daily maximum and long-term average values for the aforementioned parameters are based on the DMR data submitted from year    2021-2023.

             B. 	Outfall 001
	
Table 2 – Intake and Effluent Characteristics for Outfall 001
Parameter	Maximum Daily Value	Long Term Average Value	No. of Analysis	
Carboneous Biochemical Oxygen Demand (CBOD5)	40.90 mg/l	175.64 lbs/day	10.88 mg/l	47.18 lbs/day	36`	
Chemical Oxygen Demand (COD)	130 mg/l	563.78 lbs/day	--	--	1	
Total Organic Compound (TOC)	5.02 mg/l	21.77 lbs/day	--	--	1	
Total Suspended Solids (TSS)	10.8 mg/l	46.84lbs/day	--	--	1	
Ammonia (as N)	4.0 mg/l	17.34 lbs/day	1.267 mg/l	5.94
 lbs/day	36	
Flow	4.17 MGD	0.52 MGD	Continuous	
Temperature (winter)	73.2oF	--	Continuous	
Temperature (summer)	96.8ºF	--	Continuous	
pH	10.4 s.u. maximum	7.20 s.u. minimum	36	
Chlorine, Total Residual	0.20 mg/l	0.86
lbs/day	0.032 mg/l	0.139 lbs/day	36	
Fecal Coliform	2600 col/100 ml	20.78 col/100 ml	36	
Nitrate-Nitrite (as N)	1.79 mg/l	7.76 lbs/day	--	--	1	
Nitrogen (as N), Total	7.4 mg/l	32.09 lbs/day	2.40 mg/l	10.40 lb/day	36	
Phosphorus (as P), Total	14.69 mg/l	63.70 lbs/day	1.225 mg/l	5.31 lbs/day	36	
Sulfate (as SO4)	226 mg/l	980 lbs/day	--	--	1	
Iron	2.27 mg/l	9.84 lbs/day	--	1	
Antimony, Total	<0.06 mg/l	0.26	--	--	36	
Chromium, Total	0.21  mg/l	0.91 lbs/day	0.11 mg/l	0.47
 lbs/day	36	
Copper, Total	0.0028 mg/l	0.012
lbs/day	--	--	1	
Zinc, Total	0.0165 mg/l	--	--	--	1	

	Note: 	Outfall 001 – Those results reported based on more than one sample are based on DMR data submitted from year 2021-2023. Results based on one sample are included herein from renewal application submitted in April 2024.

VIII. 	WATER QUALITY LIMITATIONS BASED ON WASTELOAD ALLOCATION 

Parameter	Average	
CBOD5	13 mg/l (73.73 lbs/day)	
Total NH3-N	2.095 mg/l (11.88 lbs/day)	
DO (min.)	6.0 mg/l	
TSS	30 mg/l	
e-coli (col/100ml)	126 	
TN	16.0 lbs/day	
TP	10.0 lbs/day	
pH (s.u.)	6.0-9.0	

CATEGORICAL GUIDELINE LIMITATIONS CALCULATIONS

See Attachment A

VII.	TOXICITY SCREENING

See Attachment B

VIII.	WATER QUALITY CALCULATIONS

See Attachment C

XI.	PROPOSED FINAL LIMITATIONS 

1.	Average Permit Limitations

Outfall	Parameter	Categorical Limitation	Water Quality Limitation	Present Permit Limitation	Proposed Permit Limitation	Basis1	
MS0040215-001	Flow (MGD)	--	--	R	R	EJ	
	pH (min.)	--	6.0 s.u.	6.0 s.u.	6.0 s.u.	MSWQS	
	CBOD5	--	73.73 lbs/day
(13.0 mg/l)	73.73 lbs/day
(R mg/l)	73.73 lbs/day
(R mg/l)	PPR/WLA	
	DO (min.)		6.0 mg/l	R mg/l	6.0 mg/l	WLA	
	Nitrogen (Total)3	--	16.0 lbs/day	16.0 lbs/day (R mg/l)	16.0 lbs/day
(R mg/l)	WLA/ WQM	
	Phosphorous (Total)3	--	10.0 lbs/day	10.0 lbs/day (R mg/l)	10.0 lbs/day
(R mg/l)	WLA/ WQM	
	NH3-N3	--	11.88 lbs/day (2.098 mg/l)	11.88 lbs/day (R mg/l)	11.88 lbs/day (R mg/l)	WLA/
WQM	
	Residual Chlorine, Total2,4	2.58 lbs/day	0.75 lbs/day (0.172 mg/l)	0.73 lbs/day (R mg/l)
	0.73 lbs/day (R mg/l)	PPR/ABS MSWQS	
	E-coli (col/100 ml)	--	126	126
	126	MSWQS/WLA	
	Antimony, Total2	2.36 lbs/day	--	2.36 lbs/day (R mg/l)	2.36 lbs/day (R mg/l)	CG	
	Chromium, Total2	0.92 lbs/day	--	0.92 lbs/day (R mg/l)	0.92 lbs/day
(R mg/l)	CG	
MS0040215-104	Flow (MGD)	--	--	R	R	EJ	
	pH (min.)	--	6.0 s.u.
	6.0 s.u.	6.0 s.u.	MSWQS	
	Total Suspended Solids (TSS)2	--	--	133.0
lbs/day
	133.0
lbs/day	PPR/ ABS	
	Total Organic Carbon (TOC)2	--	--	73.0
lbs/day
	73.0
lbs/day	PPR/ ABS	

2.	Maximum Permit Limitations

Outfall	Parameter	Categorical Limitation	Water Quality Limitation	Present Permit Limitation	Proposed Permit Limitation	Basis1	
MS0040215-001	Flow (MGD)	--	--	R	R	EJ	
	pH (max.)	--	9.0 s.u.	9.0 s.u.	9.0 s.u.	MSWQS	
	CBOD5	--	--	R lbs/day
(R mg/l)	R lbs/day
(R mg/l)	PPR/EJ	
	Temperature (ºF) - Winter	--	90	90	90	MSWQS	
	Temperature (ºF) - Summer	--	90	97	97	PPR	
	Nitrogen (Total)	--	--	R lbs/day
(R mg/l)	R lbs/day
(R mg/l)	PPR/EJ	
	Phosphorous (Total)	--	--	R lbs/day
(R mg/l)	R lbs/day
(R mg/l)	PPR/EJ	
	NH3-N	--	--	R lbs/day
(R mg/l)	R lbs/day
(R mg/l)	PPR/EJ	
	Residual Chlorine, Total2,4	4.40 lbs/day	1.28 lbs/day (0.296 mg/l)	1.25 lbs/day (R mg/l)
	1.25 lbs/day (R mg/l)	PPR/ ABS/ MSWQS	
	E-coli (col/100 ml)	--	410	410
	410	MSWQS	
	Antimony, Total2	4.62 lbs/day	--	4.62 lbs/day (R mg/l)	4.62 lbs/day (R mg/l)	CG	
	Chromium, Total2 	1.83 lbs/day	--	1.83 lbs/day (R mg/l)	1.83 lbs/day
(R mg/l)	CG	
MS0040215-104	Flow (MGD)	--	--	R	R	EJ	
	pH (max.)	--	9.0 s.u.	9.0 s.u.	9.0 s.u.	MSWQS	
	Total Suspended Solids (TSS)2	--	--	266 
lbs/day
	266
lbs/day	PPR/ ABS	
	Total Organic Carbon (TOC)2	--	--	146 
lbs/day
	146
lbs/day	PPR/ ABS	
1 MGD = Million Gallons per Day; R = Report only; PPR = Previous Permit Requirement; EJ = Engineering  Judgment; MSWQS = State of Mississippi Water Quality Standards; WLA = Waste Load Allocation (issued on March 12, 2025); ABS = Anti-backsliding Provisions (40 CFR §122.44(l)); CG = Categorical Guidelines - 40 CFR Part 415 – Inorganic Chemicals Manufacturing Point Source Category, Subpart BN – Sodium Chlorate Production Subcategory. 

2 Water quality-based limitations, existing permit-based limitations, and technology-based (categorical) limitations were evaluated as shown in the table above to determine the proposed limits, with the most stringent of all three limits proposed since it will be more protective of water quality. Even though the categorical limitations were calculated higher than the present permit limitations, the applicant has demonstrated the ability and technology to meet the current limits. Therefore, the limits originally set in the permit will not be changed during this renewal for the aforementioned parameters based on the Anti-Backsliding provisions of the 11 Miss. Admin. Code Pt. 6, R. 1.1.4.A(4)(e). of Wastewater Regulations for NPDES Permits.

3 WQM – The proposed limits for ammonia (as N), total nitrogen, and total phosphorous are based on the WLA and    water quality model report submitted in September 2016 by the facility.

4 The sampling for the total residual chlorine shall only be conducted when Hydrogen Peroxide is not discharging. 

5 Outfall 001 shall be monitored for flow and temperature with a continuous recorder. All other parameters, with the exception of DO, total residual chlorine, total antimony, total chromium, E.coli, and pH shall be monitored once per week with a 24-hour composite sampling of the effluent. Total antimony and total chromium shall be monitored twice per year with a 24-hour composite sampling of the effluent. DO and total residual chlorine shall be monitored once per week with a grab sample of the effluent. E.coli and pH shall be monitored twice per month with a grab sample of the effluent. 

  The monitoring and reporting requirements for Outfall 104 was established in previous permitting actions and are retained in the proposed permit based on the anti-backsliding provisions of 11 Miss. Admin. Code Pt. 6, R. 1.1.4.A(4)(e). of the Wastewater Regulations for NPDES Permits.

6 Temperature – In accordance with the State of Mississippi Water Quality Criteria, the maximum water temperature shall not exceed 90ºF (32.2ºC) in streams, lakes, and reservoirs. In addition, the discharge of any heated waters into a stream, lake, or reservoir shall not raise temperatures more than 5ºF (2.8ºC) above natural conditions for temperatures. 

  The proposed NPDES permit contains instream monitoring requirements for temperature which will allow the facility to discharged heated waters (in excess of 90ºF) during the summer (not to exceed 97°F) as long as the temperature of the effluent does not cause the background temperature of the receiving stream to exceed 90ºF after mixing nor shall it cause it to rise more than 5ºF above natural conditions.  Instream monitoring is required to verify compliance. Permit conditions remain the same as in previous permits and require monitoring of the receiving stream upstream and downstream of the effluent discharge point to ensure that the effluent temperature does not cause an exceedance of the State’s temperature criteria for the receiving stream. 

ATTACHMENT A

CATEGORICAL GUIDELINE LIMITATIONS CALCULATIONS

CATEGORICAL GUIDELINE LIMITATIONS CALCULATIONS

	Outfall 001

Sodium Chlorate Production rate: 537 tons/day (1,074,000 #/day). The average daily production rate is an average of the production rates provided by the applicant in the renewal application.  

	From 40 CFR 415.663:

	Daily Maximum	Monthly Average	
Pollutant	BAT Limitation	Permit Limitation	BAT Limitation	Permit Limitation	
Antimony (T)	0.0043*	4.62 #/day	0.0022*	2.36 #/day	
Chromium (T)	0.0017*	1.83 #/day	0.00086*	0.92 #/day	
Chlorine (T.R.)	0.0041*	       4.40 #/day	0.0024*	2.58 #/day	

* pounds pollutant allowable per 1000 pounds product

ATTACHMENT B

TOXICITY SCREENING

ATTACHMENT C
WATER QUALITY CALCULATIONS

Attachment C
Water Quality Calculations

The maximum 30-day value for flow at Outfall 001 is 0.726 MGD. This value is based on DMR data from year 2021-2023. 

The  7Q10 flow of receiving water (Tenn-Tom Waterway)  = 337 cfs (217.81 MGD)

			IWC =  100 * [Qw / (Qw + Qr)]
			         =  0.331 %

Because IWC < 10%, a mixing zone study was requested.  Based on the study (submitted May 16, 1997), a mixing zone ratio of 15.6:1 was established.  Thus, the calculated IWC of 6.41% is considered for deriving water quality limitations for total residual chlorine.

Parameter	Acute Numeric Criteria	Chronic Numeric Criteria	Human Health Criteria (Organism Only)	
Chlorine	19 µg/l	0.019 mg/l	11 µg/l	0.011 mg/l	-	-	

Calculations

Daily Maximum Limitation 	= Acute Criteria Value / (IWC/100)

Chlorine, Total Residual		= 0.019 mg/l / (6.41/100)
				= 0.296 mg/l 

Monthly Average Limitation 	= Chronic Numeric Value / (IWC/100)

Chlorine, Total Residual 	= 0.011 mg/l / (6.41/100)
				= 0.172 mg/l