Title: PERMIT RATIONALE
Author: Preferred Customer
Last saved by: Rajeev Gupta
Company: Dell Computer Corporation

PERMIT RATIONALE FOR REISSUANCE
Weyerhaeuser NR Company, Philadelphia Facility
Neshoba County
Philadelphia, Mississippi
Water NPDES No. MS0001961
March 20, 2024

I.	FACILITY INFORMATION

Facility Name:  Weyerhaeuser NR Company, Philadelphia Facility
Facility Address:  1016 Weyerhaeuser Road 
Philadelphia, MS 39350
Philadelphia, 
Permit No.:  MS0001961
SIC:  2421
Permit Writer:  Rajeev Gupta
EPD Branch:  Water II Branch

II.	NATURE OF BUSINESS

Weyerhauser NR Company, Philadelphia Facility is an existing facility engaged in converting pine logs into wood products, wood chips, and dimensional lumber.

III.	EFFLUENT AND RECEIVING STREAM FLOW DATA

	The facility has three outfalls which they have applied to be permitted for.  The effluent 
	from Outfall 001 consists of non-contact cooling water, storm water runoff from ash handing, fire
	protection water, mill wash down water, air compressor blow down, and storm water runoff from 
	wood residuals storage area.  The long term average daily discharge rate from this outfall as 
	reported in the application is 0.0032 MGD.  The effluent from Outfall 002 consists of non-contact 
	cooling 	water, storm water runoff and wet decking water.  The long term average daily discharge 
	rate from this outfall as reported in the application is 0.00119 MGD).  The effluent from Outfall 
003 consists of discharge from recovery and treatment of ground water from the remediation system located at the woodwaste landfill at the facility.  The long term average daily discharge rate from this outfall as reported in the application is 0.13 MGD.  The facility spray irrigates the treated effluent on the closed part of the landfill area during dry weather conditions.

All three outfalls discharge to unnamed tributaries of Kentawka Canal.  Kentawka Canal is located in the Pearl River Basin.  The 7Q_10 of the unnamed tributaries is 0 MGD.  

IV.	303(d) and TMDL ISSUES

The receiving stream does not appear on the 2022 State of Mississippi 303(d) List of Impaired Waterbodies. This permit complies with the following applicable TMDLs:
•	Fecal Coliform TMDL for Segments of the Pearl River, the Strong River, Halls Creek, and Pretty Branch Pearl River Basin, Copiah, Pearl River, Simpson and Lawrence Counties (Final January 2012)
•	Total Maximum Daily Load Designated Streams in the Pearl River Basin for Impairment Due to Sediment (March 25, 2009; ID# 50932501)
•	Total Maximum Daily Load Total Nitrogen and Total Phosphorus for the Pearl River Pearl River Basin (Final Report June 29, 2009)
•	Total Maximum Daily Loads for The Legacy Pesticides DDT and Toxaphene, in the Pearl River, South Independent Streams, and Lower Mississippi River Basins (January 2007; ID# 507010401)
•	Fecal Coliform TMDL for Pearl River Pearl River Basin, Hancock County, Mississippi (Final Report December 2000; ID# 500121503)
•	TMDL for Low pH in the Pearl River Pearl River Basin Neshoba, Leake, Hinds, Rankin, and Hancock Counties, Mississippi (Final TMDL December 2000; ID: 500121501)
•	Fecal Coliform TMDL for Pearl River Pearl River Basin, Marion County, Mississippi (Final Report December 2000; ID# 500121502)
•	Fecal Coliform TMDL for Segments of the Pearl River, the Strong River, Halls Creek, and Pretty Branch Pearl River Basin, Copiah, Pearl River, Simpson and Lawrence Counties (ERRATA  August 2021)
•	pH TMDL for the Strong River Watershed Pearl River Basin Rankin, Scott, Smith, and Simpson Counties, Mississippi (Final Report May 2014)
•	Total Maximum Daily Load TMDL Development for Toxicity due to Pesticides and Other Pollutants in the Pearl River Leake County downstream of Carthage, Mississippi and Leake County upstream of Carthage, Mississippi (HUC 03180001) Pearl River Basin, Mississippi (July 2, 2001)
•	Pearl River and Yockanookany River Phase One Total Maximum Daily Load for Mercury Pearl River Basin( Final Report February 2004; ID: 504021701)
•	Fecal Coliform TMDL for Pearl River Pearl River Basin, Hinds County, Mississippi (Final Report December 1999; ID# 599121502)

V.	TYPE OF WASTEWATER TREATMENT

The effluent from Outfall 001 passes through a debris (sedimentation) separator/skimmer with an oil/water separator prior to being discharged.

The effluent from Outfall 002 passes through a settling pond and then a debris (sedimentation) separator/skimmer prior to being discharged.

The effluent from Outfall 003 passes through a holding tank with an oil/water separator.  The wastewater is then passed through a 50 micron filter system and finally through a granular activated carbon filter prior to being discharged or land applied.

VI.	EPA APPLICABLE CATEGORICAL GUIDELINES

The facility is subject to the following: 40 CFR Part 429 – Timber Products Processing Point Source Category, Subpart K – Sawmills and Planing Mills Subcategory (40 CFR 429.123) and Subpart I – Wet Storage Subcategory (40 CFR 429.103).

VII.	DATA FROM APPLICATION FORM 2C

	Outfall 001:
Parameter | Maximum Daily Value | # of Samples
BOD (mg/l) | 11 | 2
COD (mg/l) | <15 | 1
TOC (mg/l) | 5.0 | 1
TSS (mg/l) | 59.4 (long term average 17) | 14
Ammonia (mg/l) | 2.86 | 1
Flow (MGD) | 0.0094 (long term average 0.0032) | 14
Temp °C (°F) (winter) | Ambient | Est.
Temp °C (°F) (summer) | 81.5 (long term average 53.3) | 7
pH (min.-max.) (S.U.) | 6.4-7.3 | 14
Oil & Grease (mg/l) | 1.6 mg/L (long term average BDL) | 1

	Outfall 002:
Parameter | Maximum Daily Value | # of Samples
BOD (mg/l) | 45 | 3
COD (mg/l) | 79 | 1
TOC (mg/l) | 29.9 | 1
TSS (mg/l) | 138 (long term average 32) | 12
Ammonia (mg/l) | 2.86 | 1
Flow (MGD) | 0.035 (long term average 0.00119) | 12
Temp °C (°F) (winter) | Ambient | Est.
Temp °C (°F) (summer) | 82.4(long term average 61.2) | 12
pH (min.-max.) (S.U.) | 6.5 – 7.3 | 12

	Outfall 003:
Parameter | Maximum Daily Value | # of Samples
BOD (mg/l) | 10 | 1
COD (mg/l) | 59 | 1
TOC (mg/l) | 19.4 | 1
TSS (mg/l) | 20 | 1
Ammonia (mg/l) | 1.4 | 1
Flow (MGD) | 0.9988 (long term average 0.1323) | 22
Temp °C (°F) (winter) | Ambient | Est.
Temp °C (°F) (summer) | Ambient | Est.
pH (min.-max.) (S.U.) | 6.6-7.5 | 22
Pentachlorophenol (mg/l) | BDL | 22

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 
	
	A.  OUTFALL 001
	
Average Permit Limitation

Parameter

Categorical Limit

Water Quality Limit

Present Permit Limit

Proposed Permit Limit

Basis

Sample 
Type

Monitoring Frequency

Oil and Grease | --- | --- | 10 mg/L | 10 mg/L | PPL | Grab | Monthly
TSS | --- | --- | 30 mg/L | 30 mg/L | PPL | Grab | Monthly
Temp. (Deg F) | --- | --- | Report | Report | PPL | Instantaneous | Monthly
pH (S.U.) (min.) | 6.0 | 6.0 | 6.0 | 6.0 | MSWQS | Grab | Monthly
Flow (MGD) | N/A | N/A | Report | Report | PPL | Instantaneous | Monthly

Maximum Permit Limitation

Parameter

Categorical Limit

Water Quality Limit

Present Permit Limit

Proposed Permit Limit

Basis

Sample 
Type

Monitoring Frequency

BOD_5 | --- | --- | Report | Report | PPL | Grab | Annually
Oil and Grease | --- | --- | 15 mg/L | 15 mg/L | PPL | Grab | Monthly
TSS | --- | --- | 60 mg/L | 60 mg/L | PPL | Grab | Monthly
Temp. (Deg F) | --- | 90 | 90 | 90 | PPL | Instantaneous | Monthly
pH (S.U.) | 9.0 | 9.0 | 9.0 | 9.0 | MSWQS | Grab | Monthly
Flow (MGD) | N/A | N/A | Report | Report | PPL | Instantaneous | Monthly
Basis: MSWQS=Mississippi Water Quality Standard; PPL=Present Permit Limit

There shall be no discharge of process wastewater from Outfall 001. Process Wastewater is defined 
any water which, during manufacturing or processing, comes into direct contact 
with or results from the production or use of any raw material, intermediate product, 
finished product, by-product, or waste product  (40 CFR 401.11).  The term “process 
wastewater” specifically excludes non-contact cooling water, material storage yard runoff 
(either raw material or processed wood storage), boiler blowdown, and wastewater from 
washout of thermal oxidizers or catalytic oxidizers, wastewater from biofilters, or 
wastewater from wet electrostatic precipitators used upstream of thermal oxidizers or 
catalytic oxidizers installed by facilities covered by subparts B, C, D or M to comply with 
the national emissions standards for hazardous air pollutants (NESHAP) for plywood and 
composite wood products (PCWP) facilities (40 CFR Part 63, subpart DDDD). For the dry 
process hardboard, veneer, finishing, particleboard, and sawmills and planing mills 
subcategories, fire control water is excluded from the definition. (40 CFR Part 429.11)

	B.  OUTFALL 002
	
Average Permit Limitation

Parameter

Categorical Limit

Water Quality Limit

Present Permit Limit

Proposed Permit Limit

Basis

Sample 
Type

Monitoring Frequency

TSS | --- | --- | 30 mg/L | 30 mg/L | PPL | Grab | Monthly
Temp. (Deg F) | --- | --- | Report | Report | PPL | Instantaneous | Monthly
pH (S.U.) (min.) | 6.0 | 6.0 | 6.0 | 6.0 | MSWQS | Grab | Monthly
Flow (MGD) | N/A | N/A | Report | Report | PPL | Instantaneous | Monthly

Maximum Permit Limitation

Parameter

Categorical Limit

Water Quality Limit

Present Permit Limit

Proposed Permit Limit

Basis

Sample 
Type

Monitoring Frequency

BOD_5 | --- | --- | Report | Report | PPL | Grab | Annually
TSS | --- | --- | 60 mg/L | 60 mg/L | PPL | Grab | Monthly
Temp. (Deg F) | --- | 90 | 90 | 90 | PPL | Instantaneous | Monthly
pH (S.U.) | 9.0 | 9.0 | 9.0 | 9.0 | MSWQS | Grab | Monthly
Flow (MGD) | N/A | N/A | Report | Report | PPL | Instantaneous | Monthly
Basis: MSWQS=Mississippi Water Quality Standard; PPL=Present Permit Limit

1.  	There shall be no discharge of process wastewater from Outfall 002. Process Wastewater is defined any water which, during manufacturing or processing, comes into direct contact 
	with or results from the production or use of any raw material, intermediate product, 
	finished product, by-product, or waste product  (40 CFR 401.11).  The term “process 
	wastewater” specifically excludes non-contact cooling water, material storage yard runoff 
	(either raw material or processed wood storage), boiler blowdown, and wastewater from 
	washout of thermal oxidizers or catalytic oxidizers, wastewater from biofilters, or 
	wastewater from wet electrostatic precipitators used upstream of thermal oxidizers or 
	catalytic oxidizers installed by facilities covered by subparts B, C, D or M to comply with 
	the national emissions standards for hazardous air pollutants (NESHAP) for plywood and 
	composite wood products (PCWP) facilities (40 CFR Part 63, subpart DDDD). For the dry 
	process hardboard, veneer, finishing, particleboard, and sawmills and planing mills 
	subcategories, fire control water is excluded from the definition. (40 CFR Part 429.11)

2.	There shall be no discharge of debris from the log spray pond. The term "debris" means
	wood material such as bark, twigs, branches, heartwood or sapwood that will not pass 
	through 	a 2.54 cm (1.0 in) diameter round opening.

	C.  OUTFALL 003
	
Average Permit Limitation

Parameter

Categorical Limit

Water Quality Limit

Present Permit Limit

Proposed Permit Limit

Basis

Sample 
Type

Monitoring Frequency

Penta-
chlorophenol

---

0.0122

0.007

0.007

PPL

Grab

Monthly

pH (S.U.) (min.) | 6.0 | 6.0 | 6.0 | 6.0 | MSWQS | Grab | Monthly
Flow (MGD) | N/A | N/A | Report | Report | PPL | Totalizer | Monthly

	   	Maximum Permit Limitation

Parameter

Categorical Limit

Water Quality Limit

Present Permit Limit

Proposed Permit Limit

Basis

Sample 
Type

Monitoring Frequency

Penta-
chlorophenol

---

0.0158

0.011

0.011

PPL

Grab

Monthly

pH (S.U.) | 9.0 | 9.0 | 9.0 | 9.0 | MSWQS | Grab | Monthly
Flow (MGD) | N/A | N/A | Report | Report | PPL | Totalizer | Monthly
Basis: MSWQS=Mississippi Water Quality Standard; PPL=Present Permit Limit

There shall be no runoff from the land application of treated groundwater. Furthermore, land application of wastewater shall not take place during rainfall or saturated conditions.

ATTACHMENT A

Water Quality Calculations

For Outfall 003

Long term average for flow for Outfall 001 as reported on the Form 2C = 0.0032 MGD
Flow rate for Outfall 003 = 0.0039 MGD**

**This is the flow rate which the existing permit limits are based on for Total Pentachlorophenol.  The flow from this outfall  has increased since the last permitting cycle.  However, the facility has agreed to accept the mass limits found in the existing permit which are based on 0.0039 MGD.  

7Q_10 of unnamed tributary of Kentawka Canal = 0 MGD

Instream Waste Concentration = 100 * (0.0039/(0.0039+0.0032)) = 54.9 %

Parameter			Acute Screening Value		Chronic Screening Value
Total Pentachlorophenol	      0.0087 mg/L			     0.0067 mg/L 	

Total Pentachlorophenol, Acute	0.0087/0.549 = 0.0158 mg/L
Total Pentachlorophenol, Chronic	0.0067/0.549 	= 0.0122 mg/L

5197 PER20230001