DEQp00021598

DIVISION OF WATER QUALITY
January 15, 2002
MEMORANDUM
TO: David Goodrich, Supervisor
NPDES Permitting and Engineering Unit
FROM: Grady Do on, Environmental Engineeru�.,,; `M ,
Faye ev 1 e egional Office %
THROUGH: Paul Ra 1 ter Quality Regional Supervisor
SUBJECT: Renewal of NPDES Permit
E.I. DuPont de Nemours & co., Inc., Fayetteville Works (near Duart)
NPDES Permit No. NCO03573
Bladen County
Please find enclosed the staff report and recommendations of the Fayetteville Regional
Office concerning the renewal of subject NPDES Permit.
If you have any questions or require any further information, please advise.
PER:GD/bs
Enclosure
cc: Kitty Kramer

SOC PRIORITY PROJECT: YES NO X
- ` tYes, SOC No.
To: NPDES Permits and Engineering Unit
Water Quality Section
Attention: Mike Templeton
Date: January 15, 2002
NPDES STAFF REPORT AND RECOMMENDATION
COUNTY: Bladen
Permit No. NC 0003573
PART I - GENERAL INFORMATION
1. Facility and Address: E.I. DuPont de Nemours & Co., Inc.
22828 NC Highway 87 W
Fayetteville, NC 28306
2. Date of Investigation: November 19, 2001
3. Report Prepared by: Grady Dobson, Environmental Engineer, FRO�J
4. Persons Contacted and Telephone Number: Michael Johnson, Environmental Coordinator
E.I. DuPont, Fayetteville Works
910-678-1155
Mr. Robert Geddie, ORC
910-678-1219
5. Directions to Site: This facility is located at the Bladen -Cumberland County line, between
Highway 87 and the Cape Fear River.
6. Discharge Point(s), List for all discharge points:
Latitude: 34° 49' 52" Longitude: 78'49'00"
Attach a USGS map extract and indicate treatment facility site and discharge point on map.
U.S.G.S. map excerpt indicating treatment facility site and discharge point attached.
U.S.G.S. Quad No. H 23 -SE U.S.G.S. Quad Name: Duart, NC
7. Site size and expansion area consistent with application? X Yes _ No If No, explain.
DuPont owns approximately 2,600 acres at this site.
8. Topography and relationship to flood plain: Relatively flat.
9. Location of nearest dwelling: None within 1,000 feet

PART I - GENERAL INFORMATION (continued)
10. Receiving stream or affected surface waters: Cape Fear River.
Classification: C
b. River Basin and Subbasin No.: 03-06-16
Describe receiving stream features and pertinent downstream uses:
The combined waste discharge from this facility flow is a wood lined
channel installed as an effluent and storm water conveyance. This
combined flow discharges over a fabri-formed concrete lined ditch until
velocities are diminished and thence to the remainder of the effluent
channel. Under normal (dry) conditions, this facility produces the flow
in the effluent channel. The Cape Fear River is located approximately
2,500 feet downstream. (The discharge point has historically been
indicated as the main stem of the Cape Fear River.)
PART II - DESCRIPTION OF WASTES AND TREATMENT WORKS
a. Volume of wastewater to be permitted: 2.0 MGD (Ultimate Design Capacity) of the
treatment plant, discharge point 001. A separate discharge (002) is not flow limited.
b. What is the current permitted capacity of the Wastewater Treatment facility? 2.0 MGD
Actual treatment capacity of the current facility (current design capacity). 2.0 MGD
d. Date(s) and construction activities allowed by previous Authorizations to Construct
issued in the previous two (2) years. N/A
e. The existing or substantially constructed wastewater treatment facilities:
Process wastewater and stromwater from the various manufacturing
areas are collected in the respective area sumps and ultimately conveyed
via a gravity flow underground process sewer pipe to the site's central
wastewater treatment plant (WWTP). Sanitary sewage is conveyed via a
separate underground sewer system to the WWTP. The permitted
flowrate of the WWTP is 2.0 MGD, with an actual average flowrate of
approximately one (1) MGD.
This untreated wastewater is commingled in the WWTP Influent Sump
where it is pumped to an 850,000 -gallon Equalization Basin. The
Equalization Basin is mixed with two floating mixers. Three (3) floating
surface aerators in the basin cool and aerate the incoming wastewater.

PART II - DESCRIPTION OF WASTES AND TREATMENT WORKS (continued)
A 17�,000-gallon Emergency Retention Tank is available for temporary
storage of unsuitable wastewater. This unsuitable wastewater, which
typically exhibit a high organic loading or a chemical to which the
WWTP activated sludge is not acclimated, is eventually treated in the
WWTP at a rate that allows for proper biological treatment.
Wastewater from the Equalization Basin is pumped to a 250,000 -gallon
Predigester Tank in which initial biological activity with the WWTP
activated sludge begins. The Predigester Tank is aerated with both a
floating surface aerator and diffused air. The partially treated
wastewater from the Predigester Tank is pumped to a 1,700,00 -gallon
Aeration Tank.
The Aeration Tank is the site of the majority of the biological activity.
The Aeration Tank is aerated by both a diffused air system located in the
bottom of the tank, and by a floating Biomixer® that injects air through
submerged rotors.
The biologically treated wastewater is then sent to two (2) in -ground
clarifiers (119,000 -gallons and 168,000 -gallons respectively) in parallel.
The clarified treated effluent is discharged to and through Outfall 001.
The wasted sludge is sent to a Dissolved Air Flotation (DAF) unit, then
to a 47,000 -gallon Sludge Storage Tank, and finally to a Rotary Filter
for thickening. The thickened sludge is dewatered in a Screw Press, and
then dried in a steam -heated dryer. The dried sludge is transported off-
site to a commercial landfill.
Non -contact process cooling water and non -process stormwater are
conveyed via surface ditches to the site's Woodlined Ditch. In addition,
excess river water flow and Outfall 001 effluent are discharged directly
to the Woodlined Ditch. The combined, total flow of water from the site
is discharged and monitored at Outfall 002. The Outfall 002 flow
averaged 14.5 MGD during the period from 1996 to 2000. (See attached
for Outfall Numbering Scheme for new NPDES Permit.)
Please provide a description of proposed wastewater treatment facilities:
None anticipated
g. Possible toxic impacts to surface waters: N/A
h. Pretreatment Program (POTWs only): N/A
In development Approved _
Should be required Not needed
'Fv t ", I

IV 1
' TART II - DESCRIPTION OF WASTES AND TREATMENT WORKS (continued)
2. Residuals handling and utilizing/disposal scheme:
a. If residuals are being land applied, please specify DWQ Permit No.
Residual Contractor:
Telephone : N/A
b. Residuals stabilization: PSRP PFRP Other
C. Landfill:
The dried sludge produced at this facility is shipped to Waste Industries,
Inc., Subtitle D landfill located east of Roseboro in Sampson County
(see Sludge Management Plan).
d. Other disposal/utilization scheme (specify):
3. Treatment plant classification (attach completed rating sheet): Class III
4. SIC Code(s): 2821, 2869, 3083, 3081, 4939
Wastewater Code(s) of actual wastewater, not particular facilities; i.e., non -contact cooling water
discharge from a metal plating company would be 14, not 56.
Primary14 Secondary 22 02 36
Main Treatment Unit Code: 0 5 0 0 1
PART III - OTHER PERTINENT INFORMATION
1. Is this facility being constructed with Construction Grant Funds or are any public monies
involved (municipals only)? N/A
2. Special monitoring or limitations (including toxicity) requests: None
3. Important SOC, JOC, or Compliance Schedule Dates (please attach):
Date
Submission of Plans and Specifications
Begin Construction
Complete Construction
i
4. Alternative Analysis Evaluation: Has the facility evaluated all of the non -discharge options
available? Please provide regional perspective for each option evaluated.
Spray Irrigation: Not practical
Connection to Regional Sewer System: Not available
Subsurface: Not practical
Other disposal options: None known

PART III - OTHER PERTINENT INFORMATION (continued)
Other Special Items:
Please find a(tached photos of the discharges from the various manufacturing facilities on the
DuPont complex. All discharges ultimately go into the Woodlined Ditch which collectively
discharge into an effluent channel that discharges to the Cape Fear River.
As you may recall, the Fayetteville Regional Office was notified by DuPont staff that high levels
of turbidity was observed entering the Cape Fear River during September 1999. That
notification resulted in an onsite visit by Ricky Revels of the FRO. That visit did reveal that
areas of the effluent channel had eroded and some channel walls were vertical. During this
period of time, the Lock Master at the US Army Corps of Engineers, Lock Number 3, also
contacted the Fayetteville Regional Office to report that an extreme amount of sediment and
turbid water were entering the River from this point.
This office requests that DuPont provide to the Division a definite plan of action (to be
incorporated into this permit or other administrative mechanism) to address this issue. Based on
the attached letter forwarded to David Goodrich dated October 20, 2000, the Company asked
"the Division of Water Quality to take the needed steps to perform the necessary modeling to
determine what, if any, changes would occur to the DuPont -Fayetteville Works NPDES Permit
should the final effluent be discharged upstream of Lock and Dam #3." This office has no other
information about this sediment problem.
It is apparent that the Company acknowledges that their effluent channel has and continues to
cause sediment to be deposited into the Cape Fear River and is willing to address this issue. This
is a very significant matter as the Company has benefited from this effluent channel for some
years and needs to address this issue SOON.
Also find attached recent pictures of the Cape Fear River showing the huge amount of sediment
in the River channel estimated to be 75% of the channel width at this location.
Further, this office has discussed with Mike Johnson an incident that was observed last summer
at the effluent channel and River confluence. While fishing, Paul Rawls, of the FRO, observed a
very young child sitting in the effluent channel playing. The area of the confluence is a local
fishing area that citizens stand to fish "off of the bank". Staff has observed, on numerous
occasions, citizens standing in the effluent channel and sediment delta fishing. We understand
that this may be a unique request but we feel strongly in requesting that the Company post signs
notifying the public of the effluent channel. We feel that DENR should make the public aware
that this is not a stream but an effluent channel and is not intended to be used for primary and
secondary recreation.
You may be aware of the incident that occurred with the permittee during 2001. Very briefly,
the facility discovered the presence of hexafluoroacetone hydrate (HFA) in the WWTP effluent.
HFA, based On conversations with DuPont staff, was believed to be generated and destroyed in
the production process and based on all theory was not to make it to the WWTP or the outfall.
Again, based on self reporting and monitoring performed by the permittee, this compound did
make it to the effluent and DuPont, in a very timely manner, notified the regionaroffice and
began emergency action to modify its treatment system to address this issue. As understood,
HFA is an intermediate that is formed in the NAFION process.
This matter is brought forth in this report to address and ask for clarification of Part III C. of the
NPDES Permit. This portion of the Permit requires the permittee to "notify the Permit Issuing
Authority as soon as it knows or has reason to believe" any toxic pollutant which is not limited in
the Permit will exceed various thresholds outlined in the Permit. During this emergency event, it
r became apparent to this office that various processes and interaction of processes at the

I 'PART III - OTHER PERTINENT INFORMATION (continued)
DuPont facility have the potential to generate toxic compounds not listed in the Permit. Based
on inquiries of DWQ Central Office staff and others, these compounds cannot be readily tested
for and reference material on these compounds is not easily acquired.
It is understood that the permittee has requested of the Central Office clarification on Part III C
as to when notification is appropriate. Specifically, we ask, is reporting necessary under this Part
III C when it is "Calculated" that there is a reasonable potential for a toxic compound to be
present in the waste stream or should the permittee report confirmed measured levels of toxic
compounds that may not be listed in the Permit? This question is important because some
compounds can only (to our knowledge) be detected with analytical procedures developed by
DuPont and even then can only be measured down to the parts per million level.
We request that this issue be outlined in the cover letter of the new Permit or in a separate letter
forwarded from the Central Office (if not previously forwarded to the permittee) to officially
address the question and enable this office to better enforce the NPDES Permit.
This matter is of particular importance when considering the complex nature of the wastestream
and various uses of the Cape Fear River.
PART IV - EVALUATION AND RECOMMENDATIONS
It is the recommendation of this office that NC0003573 be reissued in keeping with basinwide strategy,
provided all concerns have been satisfactorily addressed.
Signature of Pr rer
t .%
Water Quality Regional Supervisor
Date

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DuPont - Fayetteville Works NPDES Permit No. NC000357;
1
ATTACHMENT 1
Sludge Management Plan
The DuPont — Fayetteville Works operates a Class 3 Wastewater Treatment Plant that is
comprised of a single -stage activated sludge biological system.
Excess sludge is removed from the system by diverting part of the Recycled Activated
Sludge (at approximately 0.6% solids) from the clarifiers to a Dissolved Air Floatation (DAF)
unit for initial thickening.
The sludge from the DAF (at approximately 3% solids) is transferred to a Mix Tank where
polymer agents are added to enhance the dewatering process.
The semi -thickened sludge is transferred from the Mix Tank to a Rotary Filter for final
thickening, whereby the sludge is thickened to 6% solids.
The thickened sludge is then transferred to a Screw Press where it is dewatered to a
concentration of 9-20% solids.
Following the Screw Press, the sludge is dried in steam heated dryers to a concentration of
40% - 55% solids.
On the average, the weekly quantity of generated dried sludge is 13,000 lb.
The dried, non -hazardous sludge is transported off-site to a commercial Subtitle D landfill.
This sludge is currently being disposed of at the Waste Industries' Sampson County Landfill near
Roseboro, NC.

DuPont - Fayetteville Works
MA
Potential Facility Changes
ATTACHMENT 2
Outfall Numbering
NPDES Permit No. NC0003573
algae and/or slime inside the scrubber, a biocide will likely be added to the water in the scrubber.
There will be a purge of some volume of the scrubber water on a continuous basis, so the biocide
will be discharged to Outfall 002. At this time, no decision has been made as to what biocide
will be used in this scrubber, but when one is chosen, DuPont will submit a revised Part 5 to
Section II of this application for Outfall 002 and Outfall 007.
Finally, stormwater associated with the APFO process area will be discharged directly to
Outfall 002 via the site's Woodlined Ditch.
Butacite0 Production Increase: Due to the anticipated increases in market demand, the
Butacite0 business is expecting a substantial increase in production of the DuPontTM Butacitee
Interlayer sheeting and PVB Resin during the next five years. A new ButaciteO PVB reactor is
scheduled to be installed within two years, and additional improvements within the Butacite0
manufacturing processes will result in the needed production increase. See the section titled
"Production Data" for more information.
Nafion® Production Increase: Due to the anticipated increases in market demand, the DuPont
Fluoroproducts monomers business is expecting a substantial increase in production during the
next five years. For the same reason, the DuPontTM NafionO membrane business is expecting a
substantial increase in production during the next five years. Both the monomers and membrane
manufacturing areas will accomplish this expanded production capability through
debottlenecking the existing processes and/or installation of new equipment. See the section
titled "Production Data" for more information.
BCH Alternate Enermy Proiect: The BCH Alternate Energy Project located at the DuPont
Fayetteville Works went into bankruptcy in 1998, and the project's physical facility and
equipment were sold. Therefore, all reference to this facility should be removed from the subject
NPDES permit.
Outfall 002 Discharge Relocation: During a drought condition during the summer of 1999, the
DuPont effluent channel that conveys the site's final water discharge to the Cape Fear River
experienced sloughing of the streambanks into the flowing effluent, resulting in excessive
sediment discharge into the river. DuPont has initiated a study to determine a cost effective
remedy this situation. Currently, two options are being considered:
Option 1: Collect the total flow from :Outfall 002 and convey it via a pipeline to the Cape Fear
River upstream of Lock & Dam #3.
Option 2: Collect the total flow from Outfall 002 and convey it via a pipeline to the Cape Fear
River downstream of Lock & Dam #3.
Option 1 is the most attractive to DuPont at this time because it is the least expensive due to
the shorter distance from Outfall 002 and the river. In addition, Option 2 would require that
DuPont lay the pipeline across the government owned property of the park facility at Lock &
Dam #3, otherwise the pipeline would have to run over a much longer, more circuitous route. It

DuPont - Fayetteville Works = NPDES Permit No. NC0003573
Potential Facility Changes
is unknown whether DuPont would receive approval from the Army Corps of Engineers to lay
this pipeline across their property.
This proposal was presented to the Division of `Vater Quality, and the single concern stated
by the division was that a discharge upstream of Lock & Dam #3 might be considered to be a
reservoir instead of a flowing river, and as such DuPont's permitted limits for BODS, nitrogen,
and phosphorous might be lowered. According to the division, a modeling exercise would have
to be performed by DWQ to determine whether or not lower permit limits would result for a
discharge upstream from the Lock & Dam. Given the anticipated growth of this site during the
next decade, it is essential that DuPont fully understand the implications of relocating the
effluent upstream of the Lock & Dam before a decision is made to do so. Therefore, DuPont is
awaiting the result of the division's modeling exercise before a decision is made on which option
will be pursued.
0
I l I

DuPont - Fayetteville Works NPDES Permit No. NCO003573
Potential Facility Changes
APFO Manufacturing: The DuPont — Fayetteville Works has been tentatively identified as
the location for the DuPontTM APFO manufacturing process. This process will produce
ammonium perfluorooctanoate (APFO), CAS No. 3825-26-1, an essential raw material for the
DuPontTm Teflon® fluoropolymer resins business. The manufacturing unit will be located either
near the existing DymetrolS manufacturing building or near the Naftone area's Vinyl Ethers
South manufacturing building.
APFO is recognized by DuPont and others as a biopersistent compound, meaning it remains
in the body or environment for extended periods of time after exposure. Due in part to APFO's
biopersistence, DuPont, alone and in collaboration with others, has made considerable
investment into studying potential health effects of APFO. DuPont's medical surveillance of its
own employees and epidemiological data from others in industry support its conclusion that
APFO does not pose a health concern to humans or animals at levels present in the workplace or
environment.
DuPont has used APFO for more than forty years with no observed health effects in workers.
APFO is used in low volumes and does not pose any significant acute or chronic risk. It is not a
genotoxic compound. It is neither a known developmental toxin nor a known human carcinogen.
APFO exhibits low environmental toxicity; tests on various aquatic life forms have shown no
adverse effects even at very high doses. APFO is not bioaecumulative in the food chain.
As with most fluorochemical processes, the wastewater from the APFO manufacturing
process is expected to have very little or no biological oxygen demand (BODS) value. In
addition, the fluoride and fluorocarbons have been related to settleability problems in the
WWTP's final clarifiers. For these reasons, DuPont proposes to create a new permitted outfall,
designated as Outfall 007, with the same monitoring requirements as the currently permitted
Outfall 006, through which the APFO process wastewater will be discharged directly to the site's
woodlined ditch and ultimately through Outfall 002. The rational behind this new outfall is
identical to that used to create Outfall 006 (See Attachment A for a letter dated March 15,1996
f from Michael E. Johnson, DuPont, to Gregory Nizich, DEM).
DuPont will conduct a study of the APFO process wastewater to verify the absence of
I significant BODS value before the project is constructed to provide support for the
appropriateness to discharge of this stream directly to the woodlined ditch. In the extremely
unlikely event that this wastewater exhibits BODS concentrations near the permitted limit of
24 mg/L, then DuPont will convey the wastewater to the site's WWTP for treatment and
discharge at Outfall 001.
The APFO wastewater will contain iodide, a new chemical to the Fayetteville Works facility.
Current estimates of the wastewater indicate that there will be approximately 365 lb/day I2 that
would convert to form approximately 477 lb/day of the potassium iodide salt (KI). The 7Q10 of
the Cape Fear River at the DuPont location is 791 cubic feet per second. At the 7Q 10 flowrate,
the concentration of potassium iodide in the river would be 112 µg/L.
An emergency oleum water scrubber will be included as an integral part of this process. In
the unlikely event of a release of oleum (a solution of S03 in H2SO4) inside the' manufacturing
building, the scrubber would remove the resulting S03 from the air. To prevent the growth of

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DuPont Fluoroproducts
DuPont Fluoroproducts
22828 NC Highway 87 W
Fayetteville, NC 28306-7332
fX-
�Y4 �T 1 2000 ATTACHMENT 3
REG.
October 20, 2000
Mr. David Goodrich
NCDENR — Division of Water Quality
Water Quality Section — NPDES Unit
1617 Mail Service Center
Raleigh, NC 27699-1617
SUBJECT: Relocation of Final Effluent Discharge
NPDES Permit No. NC0003573
Dear Mr. Goodrich:
First of all, thank you for giving me the opportunity to meet with you, Tom Belnick,
and Mike Myers last month to discuss the issue of the DuPont — Fayetteville Work's
effluent channel and the sedimentation problem that occurred from this channel during
the summer of 1999.
The purpose of this letter is to request from the Division of Water Quality a
regulatory determination as to any change in the NPDES permit limits should this site
relocate its final discharge from the current position downstream of Lock and Dam #3 to
a new position upstream of the Lock and Dam.
As you recall, the total permitted wastewater discharge from this site, which averages
about 15 MGD, enters an effluent channel that conveys the water approximately one mile
to the Cape Fear River at a point downstream of Lock and Dam #3. Over the thirty-year
history of this site, the continuously flowing effluent has eroded the channel to the point
where most of its walls are nearly vertical and the streambed is now fifteen to twenty feet
below grade. During the drought of the summer of 1999, we experienced sloughing of
the channel's banks that resulted in substantial amounts of sediment exiting the effluent
channel into the Cape Fear River. I will point out that we have not seen this problem
since that time, which I contribute to the normal rainfall we experienced this summer.
On August,20, 1999, DuPont met with Mr. Paul Rawls and Mr. Ricky Revels of the
DWQ staff in the Fayetteville Regional Office to inform them of the effluent channel
sedimentation problem. Since that time, we have been working on determining the most
effective and cost efficient means to minimize the possibility of a future recurrence of the
sedimentation problem.
After a considerable amount of field investigation and preliminary design work,
DuPont has identified two possible solutions that would minimize the future sediment
discharge from the existing effluent channel. Each of these projects would cost
E. I. du Pont de Nemours and Company Printed on Recycled Paper
FL -4 Rev. 6/99

Mr. David Goodrich Page 2 of 3
NCDE`NR — DW
Q
October 20, 2000
approximately two million dollars ($2,000,000) and their details will be discussed later in
this letter. However, the most attractive and permanent solution apparently -could result
in a lowering of the existing permitted limits in the DuPont NPDES permit, which would
make that solution unattractive. Therefore, before we can proceed, we need a definitive
answer as to whether or not the permit limits would be affected.
DESIGN OPTION 1
The first potential solution is to make physical modifications to the effluent channel
as it approaches and enters the Cape Fear River, and to install a dam structure to allow
sediment settling. This design requires straightening out the channel to reduce the
amount of stream bank erosion that occurs from the dynamic scouring of the water at
turns, and widening the channel at the river itself to slow down the water's velocity and
reduce the streambed erosion. At some point between the Lock and Dam road and the
river, a dam would be installed to create a quiescent pool for water -borne sediment to
settle before reaching the dam. An obvious downside to this plan is that there would be
substantial ongoing maintenance cost associated with the dam as well as periodic required
dredging to remove accumulated sediment from upstream of the dam. Another downside
is that with the frequent flooding of the Cape Fear River, this dam structure would be
occasionally submerged and could sustain major damage that would result in expensive
repair costs. This design has been estimated to cost approximately $1.8 million.
DESIGN OPTION 2
The second potential solution is to pipe the entire DuPont final effluent directly to
the Cape Fear River, which would allow the existing effluent channel to return to its
original, natural state as a stormwater ditch that would be dry except for rainfall runoff. It
is believed that without the continuous flow of the DuPont effluent, the channel would in
time naturally vegetate and thereby virtually eliminate all future sediment discharge to the
river. To make this option cost effective, the pipe would be laid in a line that is the
shortest distance to the river, which would place the discharge of the effluent upstream of
Lock and Dam #3. Obvious benefits of this plan are that there would be no routine
maintenance costs to DuPont, the pipeline would be less vulnerable to damage from
flooding, and overall we believe that the sediment to the river will be less than would be
seen under Option 1. This design has been estimated to cost approximately $2.2 million,
and while it would cost more for DuPont to construct this project than the one described
in Option 1, the maintenance -free aspect of this project and the complete remediation of
the sediment problem makes it an attractive option to consider.
PERMIT LIMITATION POTENTIAL CHANGE
As discussed in our meeting, there is apparently a rule or policy that could result in
lower permitted limits for this site's NPDES permit if the DuPont effluent were

Mr. David Goodrich
NCDENR — DWQ
October 20, 2000
Page 3 of 3
discharged upstream of Lock and Dam #3 because of the water body behaving as a
reservoir instead of as a flowing stream.
You indicated that a modeling exercise would have to be performed for this area of
the Cape Fear River to determine whether or not the DuPont effluent would have any
negative impact on the water. system upstream of the Lock and Dam. If the modeling
demonstrates that the effluent would result in some water impairment, then more
restrictive permit limitations would be placed on our NPDES permit. DuPont feels that
this information is imperative before we can make a decision on which of the two above
multi-million dollar projects we would select.
Therefore, I am asking that the Division of Water Quality take the needed steps to
perform the necessary modeling to determine what, if any, changes would occur to the
DuPont — Fayetteville Works NPDES permit should the final effluent be discharged
upstream of Lock and Dam #3.
Enclosed for your use is a map indicating the approximate location of the proposed
pipeline. If you should need any additional information, please let me know and I will be
happy to provide it to you.
If you have any questions regarding this letter or if you need more details, please feel
free to call me at [phone].
Enclosure
cc: Mr. Paul Rawls, NCDENR Division of Water Quality, Fayetteville
Mr. Ricky Revels, NCDENR Division of Water Quality, Fayetteville

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