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Belnick, Tom
From: Belnick, Tom
Sent: Wednesday, October 06, 2010 3:30 PM
To: Pickle, Ken; Lawyer, Mike
Cc: Bennett, Bradley
Subject: RE: Dupont Fayetteville Works NPDES N( NG0003573
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I've already sent an NPDES no comment reply back to CG&L. The relocation was approved in a permit mod dated
2/26/2008. There was no discussion of a new sediment basin in that mod, just outfall relocation due to the sediment
issues within the effluent channel. This permit expires 10/31/2011, and I don't envision reopening the permit before
renewal. I can add the sediment basin as a new treatment component at that time, but the permit writer will discuss its
purpose with DuPont. I'll put this email in the permit file, as a notice to the next permit writer to discuss any remaining
SW issues.
Tom Belnick
Supervisor, Complex NPDES Permitting Unit
NC DENR/Division of Water Quality
1617 Mail Service Center, Raleigh, NC 27699-1617
(919) 807-6390; fax (919) 807-6495
E-mail correspondence to and from this address may be subject to the North Carolina Public Records Law and may be
disclosed to third parties.
From: Pickle, Ken
Sent: Wednesday, October 06, 2010 10:50 AM
To: Lawyer, Mike
Cc: Bennett, Bradley; Belnick, Tom
Subject: RE: Dupont Fayetteville Works NPDES No
NC0003573
Hi Mike,
Further comments: Didn't mean to leave you hanging, just got sidetracked.
a) Consider that 12MGD is our current working number for the wastewater discharge flow. You think that's
erosive? It has been before. So, I suspect that the sediment basin is there to address the wastewater discharge
erosion on a day -in -and -day -out basis.
b) The boundary between NPDES and SPU may be unclear in some cases. My perspective is that this entire system
is an NPDES system by virtue of all the stormwater being commingled with a wastewater discharge (I don't think
it matters that the wastewater discharge is a 'partially treated' discharge during part of the run.)
c) Consistent with that perspective, this is not a 'stormwater' basin: it's a wastewater basin, maybe a 'tertiary
sedimentation' basin, or whatever lingo is appropriate in the wastewater world. We probably should see if the
NPDES guys think this is their basin, or not. This is critical in responding to the question from the guys at CG&L.
d) Mike, I agree, if there will be a remnant stormwater-only discharge from the old wooden channel, then the
facility will need a stormwater permit for it. As you suggest one path would be just to simply address it with
modifications to the existing NPDES wastewater permit. We have some of those permits still in our universe of
NPDES permits. But, both SPU and NPDES are trying to move away from combined permits for administrative
efficiency reasons. As weird as it might sound, it's easier/quicker/more efficient for the permittee and for the
two units, when we issue permits separately, rather than in combo permits. Suggest we get Tom Belnick's input
on this point, too. It's possible he may see it differently in this particular case. You may see it differently, too.
It's possible that Tom may want to just modify the current NPDES permit by adding stormwater provisions, and
address the splitting out of stormwater into two permits at the next scheduled renewal of his NPDES permit.
Tom?
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Ken
From: Lawyer, Mike
Sent: Friday, October 01, 2010 2:13 PM
To: Pickle, Ken; Bennett, Bradley
Cc: Patterson, Roberts Henson, Belinda; Rawls, Paul; Ventaloro, Julie
Subject: RE: Dupont Fayetteville Works NPDES No. NC0003573
Yes, I neglected to mention this facility's water usage. My understanding is that they withdrawal approximately 12mgd,
but only use what they require for processing (not sure how much) and send the rest back to the river via their current
outfall. I believe this has been the major cause for the erosion in the effluent channel and subsequent sediment
deposition into the riverjust downstream of L&D #3.
I would be curious about the wooden channel that serves as their current conveyance of general wastewater and
stormwater. If this channel is to remain, then its logical to presume that stormwater from portions of the facility would
continue to enter and discharge from it. This may need to be added to their NPDES wastewater permit as a stormwater-
only outfall to be monitored in addition to the relocated ww outfall.
Mike
Michael Lawyer, CPSWQ
Environmental Specialist
NCDENR-Division of Water Quality
Surface Water Protection Section
Fayetteville Regional Office
Direct: (910) 433-3329
Main: (910) 433-3300
Fax: (910) 486-0707
e-mail:.mike.lawyer(@ncdenr.gov (please note my current e-mail address)
*E-mail correspondence to and from this address may be subject to the North Carolina Public Records Law and may be
disclosed to third parties.
From: Pickle, Ken
Sent: Friday, October 01, 2010 1:38 PM
To: Lawyer, Mike; Bennett, Bradley
Cc: Patterson, Robert; Henson, Belinda; Rawls, Paul; Ventaloro, Julie
Subject: RE: Dupont Fayetteville Works NPDES No. NC0003573
Bradley,
• Other thoughts: I would suspect that the water usage of this facility is quite large. Aerial photos make it seem
I
ike their water intake is immediately above the dam and lock, and their discharge is immediately downstream
of the dam and lock. Now they're proposing to return the water upstream of the lock and dam, instead of
downstream. Who might be concerned about any affect on the dam? The Corps?
• NPDES wastewater ATC: Just two additional comments. First: To us this is really nota 'stormwater' basin that
they're building, right? It's a settling basin to address the sediment load picked up as the wastewater discharge
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(augmented by storm flows) erodes the effluent channel, right? The flows are commingled (all now
wastewater), and it's being built under a wastewater permit. This all looks ok to me.
• Second NPDES wastewater comment: In this case, any measurement of solids at internal outfall #001 masks the
sediment load delivered by the erosion of the effluent channel. (As I read the BIMS information, NC0003573
requires TSS measurements at internal outfall #001, but not at outfall #002.) What regulatory requirement is
driving this project? A new settling basin and the new 60" and 48" discharge lines have got to be costly. Must
be the Corps?
• I wonder if our brothers over in NPDES might want to add TSS to #002?
• NPDES stormwater? if it's all captured on site and it's all in the wastewater outfall, no comment. (Other
unpermitted stormwater outfalls?)
• WS -IV CA water supply according to BIMS.
• I don't think that we in SPU have any involvement in this project (except via NCG01 at the time of construction )
Ken
From: Lawyer, Mike
Sent: Friday, October 01, 2010 10:32 AM
To: Bennett, Bradley
Cc: Patterson, Roberts Pickle, Ken; Henson, Belinda; Rawls, Paul
Subject: RE: Dupont Fayetteville Works NPDES No. NC0003573
This facility does not have a separate stormwater permit as their NPDES wastewater permit covers stormwater
discharges in addition to wastewater plant effluent and general wastewater from a non -contact cooling tower and a
boiler. General wastewater discharges flow into a wooden ditch, which also receives stormwater. Discharges from the
facility's WWTP (internal outfall 001) also join the wooden ditch just prior to entering what is currently their effluent
channel to the Cape Fear River (outfall 002) and ultimately discharging into the River downstream of Lock and Dam #3.
My understanding of the reason they are proposing to reroute their discharge point, which would end up being
upstream of L&D #3, is that a large amount of sediment has been deposited over time into the River through the
effluent channel due to the amount and velocity of their discharges.
As far as their proposal for a stormwater basin, I'm assuming it would be to aid in detention and reduce velocity of
discharges. Bladen County is not a Phase II county and the facility is not located within an HQW or ORW watershed. The
only possible post -construction requirement might be under the Water Supply rules as that portion of the Cape Fear has
been recently reclassified as WS -IV due to the installation of a new intake near the Smithfield Packing facility in Tar Heel.
According to revised maps, the WS watershed extends from the new intake upstream into Cumberland County and
would cover the DuPont facility located near the Bladen/Cumberland County line. I don't know how much property is
owned by DuPont, but if there is any installation of new BUA associated with the outfall rerouting project and it would
put them over the 24% density threshold, then an engineered BMP would be required. The reclassification became
effective on 1/1/09 and according to a document we have concerning the reclassification, local governments had 270
days after the effective date to develop or modify water supply protection ordinances to meet the state's minimum
requirements.
Mike
Michael Lawyer, CPSWQ
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Environmental Specialist
NCDENR-Division of Water Quality
Surface Water Protection Section
Fayetteville Regional Office
Direct: (910) 433-3329
Main: (910) 433-3300
Fax: (910) 486-0707
e-mail: mil<e.lawyer@ncdenr.gov (please note my current e-mail address)
*E-mail correspondence to and from this address may be subject to the North Carolina Public Records Law and may be
disclosed to third parties.
From: Bennett, Bradley
Sent: Thursday, September 30, 2010 4:08 PM
To: Lawyer, Mike
Cc: Patterson, Robert; Pickle, Ken
Subject: FW: Dupont Fayettevile Works NPDES No. NC0003573
Hey Mike,
Take a look at the request from CG&L below. Any thoughts on this one. It doesn't appear that they have an NPDES
Stormwater permit currently. I'm not sure if they have the stormwater basin for any other reasons (post -construction
permit of some type?).
Robert, Ken —let me know if you have any feedback on this one also.
Bradley Bennett
Stormwater Permitting Unit
NC Division of Water Quality
1617 Mail Service Center
Raleigh, NC 27699-1617
Phone: (919) 807-6378
Fax: (919) 807-6494
Email: bradley.bennett@ncdenr.gov (New Email Address)
Web: http://portal.ncdenr.org/web/wq/ws/su
Email correspondence to and from this address maybe subject to the North Carolina Public Records Law and maybe disc%sed to third
parties.
From: Tsadwa, Steve
Sent: Wednesday, September 29, 2010 5:16 PM
To: Bennett, Bradley; Belnick, Tom
Cc: Henson, Belinda; Allen, Trent
Subject: Dupont Fayettevile Works NPDES No. NC0003573
We are reviewing an Authorization to Construct (ATC) application for Dupont at this facility that involves the relocation
of Outfall 002. The discharge from NPDES permitted outfall system is conveyed by a new open channel system (about
31000 ft long) to a new storm water management basin and finally discharging through approximately 1,600 If of 48"
and '.60" piping to the Cape River. Outfall 002 flows consist of storm water, non -contact cooling water, boiler blowdown
condensate, and WWTP effluent from internal Outfall 001. All of this flow is proposed to be routed through the
stormwater basin. We want to make sure there are no other applicable permits or reviews (such as stormwater) that
are required prior to issue of an ATC. We appreciate all your review comments and feedback.
Steve "Tesfu" Y:,adwn, Envir'onmentnl/Chemical Engineer
Design Management Uni-i'
Construction Gran -s & Loons Section
1633 Mnil ServicE Cen-I-er
I�aleigHt, NC 27699-163>
919.715.6230 (phone.)
919.71 5.6229 (Fax)
ste:ve, i saclvua�ncdenr.gr�v
E-mail corresponcic race to and fr^om this add►^ess may be subjec t to the North Carolina Publie Records Law and may
be disclosed to third parties.
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