NC0004308_WASTELOAD ALLOCATION_19890815

NPDES DOCUWENT SCANNIM& COVER SHEET
NPDES Permit:
NC0004308
ALCOA --y- Badin Works
Document Type:
Permit Issuance
Wasteload Allocation -� "",".
Authorization to Construct (AtC)
Permit Modification
Complete File - Historical
Staff Report
Instream Assessment (67b)
Environmental Assessment (EA)
Permit
History
Document Date:
August 15, 1989
M[ in document IN ]Prirnted an reuse paper - ignore any
coriteX.t on the reirerse side

+%Mto
State of North Carolina
Department of Natural Resources and Community Development
Division of Environmental Management
512 North Salisbury Street 0 Raleigh, North Carolina 27611
James G. Martin, Governor R. Paul Wilms
William V(W Cobey, Jr., Secretary . Director
August 15, 1989
Ms. Coralyn M. Benhart, Attorney
Aluminum Company of America.
Legal Department
Alcoa Building
Pittsburg, Pa. 15219
Subject.: Alcoa Badin Works Draft NPDES Permit
NPDES No. NCO004308
Stanly County
Dear Ms. Benhart:
I am writing in response to your letter of July 13 concerning
a modification to the recently revised NPDES permit for Alcoa's
#' Badin facility. Based upon my staff's recommendations, I will not
waive or modify any of the permit requirements at this time. The
Alcoa Company has not submitted sufficient information nor demon-
strated a comprehensive effort to address the toxicity issues
associated with the Badin Works discharges. These deficiencies in
Alcoa's effort have been outlined at several meetings between
staff of the Division of Environmental Management (DEM) and repre-
sentatives of Alcoa over the past two years.
DEM conducted an investigation into treatment methods for
cyanide. The literature indicates that Alcoa can reduce the level
of cyanide in its effluent in order to meet the permit limits. A
copy of the results were sent to Mr. Morgan E. Kommer in a letter
dated April 27, 1989. I have included another copy for your
review.
The fluoride limit will remain in effect. If the company
extends the outfall pipe 300 feet into Badin Lake and uses a jet
pump which provides 14:1 dilution, the limit will be dropped, and
effluent monitoring only will be required. If the existing
discharge location is maintained, the fluoride can be removed
through precipitation with alum or lime. An alternative method
involves filtration by activated aluminum. This method is more
effective, but is generally more expensive. However, it may be
P.O. Box 27687, Raleigh, North Carolina 27611-7687 Telephone [phone]
An Lqual Opportunity Affirmative Action Employer

feasible for an aluminum manufacturing company. Both of these
methods should be capable of meeting the limit of 24 mg/l.
I will not waive the toxicity limit or monitoring require-
ment. 15 NCAC 2B.0211 states that toxic substances can be at
"only such amounts, whether alone or in combination with other
substances or wastes as will not render the waters injurious to
public health, secondary recreation, or to aquatic life and wild-
life (either through chronic or acute exposure or through
bioaccumulation), or impair the water for any designated uses".
The toxicity test has been approved by the U.S. Environmental Pro-
tection Agency and the N.C. Environmental Management Commission as
an effective means of monitoring toxic discharges to ensure pro-
tection of the receiving waters for their designated uses. If you
are concerned that you will not be able to meet your metals limits
or whole effluent toxicity limit upon issuance of the permit, you
should file for a Judicial Order of Consent (JOC) with the Moores-
ville Regional Office. Contact Rex Gleason at [phone] for
details.
If you have any further questions about the revised permit,
please contact Trevor Clements or Dale Overcash of my staff at
(919) 733--5083.
I hope that the Division's response is satisfactory to the
company. However, if this letter does not adequately address your
concerns, you have the right to an adjudicatory hearing upon
written request within thirty (30) days following receipt of this
letter. This request must be in the form of a written petition,
conforming to Chapter 150E of the North Carolina General Statutes,
and filed with the Office of Administrative Hearings, Post Office
Drawer 11666, Raleigh, North Carolina 27604. Unless such a
request is received by this Division, the requirements contained
in the issued permit shall be final and binding.
Sincerely,
(.1 R. Paul Wilms
Attachments QQ�r
cc: Dale Overcash
cTrevo r—Grements
Rex Gleason
Central Files
David Williams

DIVISION OF ENVIRONMENTAL MANAGEMENT
July 21, 1989
MEMO TO: Ruth Clark
FROM: David Williams
THROUGH: John Dorney 9k�)
RE: Fluoride removal at Alcoa
I have reviewed the technology available for removing
fluoride from water and wastewater. The most commonly used
technology .involves precipitation of fluoride with either alum or
lime. Another, more effective, method involves filtration by
activated aluminum. This method is generally more expensive than
the others, but for an aluminwn manufacturing company it may be
feasible. All of these methods should be capable of meeting
Alcoa's fluoride limit of 24 mg/l.
There is one journal article that I have not yet been able to
locate. This article discusses research involving fluoride and
cyanide removal from pot -lining; leachate using; ozone. This
research was done by Alcoa in Pennsylvania. Hopefully, I will be
able to get this article by Monday.
Let me know if I can help any further.
JUG 2I 1989

MEMO.
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s,= Resources &Community Pevelopment

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July 13, 1989
FEDERAL ,E P� R
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1
Mr. R. Paul Wilms, Director
Division of Environmental Management
Department of Natural Resources and
Community Development
512 North Salisbury Street
Raleigh, NC 27611
Re: NPDES PERMIT NO. NCO004308 - ALUMINUM COMPANY OF
AMERIC_A, BADI_N WORKS,_ STANLY COUNTY, NORTH CAROLINA
Dear Mr. Wilms:
Aluminum Company of America ("Alcoa") hereby requests a waiver
or modification of certain conditions contained in NPDES Permit
No. NCO004308 (the "Permit") pursuant to Regulation 15 NCAC 2B
.0508(b). The Permit was issued to Alcoa by the Division of
Environmental Management ("DEM") on June 13, 1989 and
authorizes, in accordance with the limitations, requirements
and other conditions thereof, the discharge of wastewater from
Alcoa's facility in Badin, Stanly County, North Carolina. The
Permi-t was accompanied by your letter dated June 13, 1989 which
states that if any part of the Permit is unacceptable, a waiver
or modification may be requested pursuant to Regulation 15 NCAC
2B .0508(b).
The specific issues in contention relate to Outfall 009 and are
contained in Part 1.A(1) of the Permit. First, even using the
best_available technology, the effluent limitations for cyanide
and(fluori� are unattainable at the present time and are
therefore unreasonable. Second, in light of the infeasibility
of the above effluent limitations, the monitoring requirements
for chronic toxicity are unreasonable. For these reasons and
other reasons not recited above, Alcoa requests that both the
effluent limitations and the monitoring requirements be waived
or modified.
V
ALCOA
U.N''1[NNW
1988

Mr. R. Paul Wilms
July 13, 1989
Page 2
Efforts are being made to resolve the issues in contention
through negotiations with Mr. Rex Gleason of the regional
office of DEM in Mooresville, North Carolina. If the
negotiations are unsuccessful or this request for waiver or
modification is denied, we plan to request an adjudicatory
hearing in accordance with Chapter 150E of the General Statutes
of North Carolina.
Very truly yours,
Coralyn M. Benhart
Attorney
CMB/mrj
466CMB
4
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PEQf ,
cc: Conrad A. Carter - Badin Works
N
Mr. Rex Gleason (via certified mail)
Division of Environmental Management
919 North Main Street
P.O. Box 950
Mooresville, NC 28115-0950
Mr-, M- D,aleO,vercash ;P;.E . ( vi,a _ cert if"ied 'mail'.)
Supervisor, NPDES Permits Group
Division of Environmental Management
512 North Salisbury Street
Raleigh, NC 27611

State of North Carolina
Department of Natural Resources and Community Development
Division of Environmental Management
512 North Salisbury Street • Raleigh, North Carolina 27611
James G. Martin, Governor April 27, 1989 R. NuI Wilms
William W. Cobey, Jr., Secretary Director
Morgan E. Kommer, Manager
Environmental Control Programs
Aluminum Company of America
Alcoa Building
Pittsburg, PA 15219
Dear Mr. Kommer:
Subject: Draft Permit Comments
NPDES NC0004308
Alcoa-Badin Facility
Stanly Co.
I have reviewed the concerns you expressed in your letter of March 30,
1989 regarding the draft permit for Alcoa's Badin facility. I have
discussed this matter with my staff and subsequently would like to reply
to the points of interest that you outlined in your letter.
1) In Alcoa's letter of March 10, 1988 (Appendix A), Mr. Conrad Carter
stated that the 1987 study recommended the 250 mg/l sulfate limit
to which you are now objecting. I have also been informed that
Alcoa has verbally stated several times over the past year that the
company would have no problem meeting the sulfate limit. Moreover,
the sulfate concentrations found in pipe 002 during the 1987 study
ranged from 3.12 mg/l to 33.7 mg/l (Appendix B). With the maximum
concentration, 33.7 mg/l, being approximately 7 1/2 times less than
the 250 mg/1 limit proposed in the draft permit, I see no substantive
reason to increase the sulfate limit of pipe 002 to 1000 mg/l.
2) Guarding against siltation near the outfall is indeed what the
settleable solids limit for pipe 002 is intended to accomplish. NC
Water Quality Regulations charge the Division to protect all waters
of the State, including Badin Lake near Alcoa's 002 outfall. DEM is
amenable, however, to substituting a total suspended solids (TSS) limit
of 30 mg/l in lieu of the settleable solids limit.
3) The Division agrees to change the designation of Outfall 009 from
"Boiler House" to "non -contact cooling water and stormwater".
4) In reference to our reply in Item 2, we maintain that a settleable
solids limit is needed for pipe 009, especially after noting your
comment in Item 3 that pipe 009 contains a stormwater component.
However, as in item 2, DEM agrees to substitute TSS for settleable
solids.
5) DEM recognizes that a cyanide limit of 31 ug/l may be difficult to
1'O. l�)x 27687, PUleigh, North Caredina 27011-7687 -Telephone [phone]
An iryual Opportunity Affirmative Action Employer

achieve; however, we regarded your company's proposal to install a
high -rate diffuser as an indication of Alcoa's commitment to work with
DEM in finding a mutually -acceptable solution to the cyanide problem in
outfall 009. The Division used the engineering specifications provided
by your consultant, FTN Associates Ltd., to recalculate the 434 ug/l
cyanide limit instead of the 31 ug/l originally recommended for a
shoreline discharge. In addition, DEM recently conducted a thorough
investigation into the treatability of low to moderate levels of
aqueous cyanide (Appendix C). We have concluded that Alcoa could treat
this toxicant successfully enough to obtain an effluent concentration
well below the 434 ug/l recommended in the draft permit. Therefore,
DEM will not remove the numerical limit for cyanide from the new permit
and suggests that Alcoa work out a reasonable schedule for compliance
with DEM's Mooresville Regional Office by requesting a Special Order
of Consent.
6) North Carolina's water quality regulations base the cyanide standard
on total cyanide. Moreover, Alcoa has presented no information to
DEM regarding the relationship between free and total cyanide and the
associated toxicity at varying pH. Therefore the laboratory method
which you cited, ASTM-D4282-83: Test Method for Determination of Free
Cyanide in Water and Wastewater by Microdiffusion, is not acceptable.
The appropriate test for total cyanide is Method 335.2. This procedure
is detailed in the EPA document "Methods of Chemical Analysis of Water
and Wastewater", pages 335.2-1 through 335.2-8. The order number for
this document is EPA-600 4-79-02.
7) It is the experience of the Division of Environmental Management as
well as EPA that the test protocol for chronic toxicity is reproducible
and does accurately reflect instream response. Concluding that test
results are simply a matter of probability is not consistent with
the extremely large database of effluent toxicity test results which
show that response is dependent on dose. This relationship clearly
demonstrates that a toxic effluent becomes more toxic as concentration
increases. In regard to protocol that "is not sufficiently advanced",
toxicity testing procedures have undergone extensive peer review and
are considered sound and well-defined. Toxicity testing procedures are
utilized by the State laboratory on a continual basis and have been
found to produce accurate, reproducible results. Therefore, the Division
suggests that Alcoa discuss the test with its eventual contract laboratory
so that your firm may become more comfortable with established protocol.
Please be aware that this test must be performed by a certified
laboratory. Attached is a list of laboratories certified by the State
of North Carolina (Appendix D).
If you wish to make the changes proposed in items 2 and 4, please respond
to the Division by May 12, 1989. If these changes are not acceptable, or
if after reviewing the DEM's reply to items 1, 3, 5, 6, and 7, you find that
the limits in the draft permit are unacceptable to your company, you have
the right to an adjudicatory hearing upon written request within thirty days
(30) following the date of the issued permit. This request must be in the
form of a written petition, conforming to Chapter 150B of the North Carolina
General Statutes, and filed with the Office of Administrative Hearings, Post
Office Drawer 116661 Raleigh, North Carolina 27604. If we do not receive any
response, the current draft permit will be final and binding.

Please contact either Arthur Mouberry or Trevor Clements at [phone]
if you desire further clarification of this matter.
erely /
V
R. Paul Wilms
RPW/jdv ,
Attachments
cc: Conrad Carter, Badin Facility, Alcoa
Steve Tedder, Water Quality Section Chief
Arthur Mouberry, Permits and Engineering
Trevor Clements, Technical Services
Rex Gleason, Mooresville Regional Office
Central Files

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Statc of North Carolina
Department of Natural Resources and Community Development
Division of Environmental Management
512 North Salisbury Street • Raleigh, North Carolina 27611
James G. Martin, Governor R. Paul Wilms
William W Cobey, Jr., Secretary Director
April 3, 1989
Mr. Morgan E. Kommer, Manager
Environmental Control Programs
Aluminum Company of America
ALCOA Building
Pittsburgh, PA 15219
Subject: DRAFT Permit Comments
NPDES No. NCO004308
ALCOA - Badin
Stanly County
Dear Mr. Kommer:
This letter is to acknowledge receipt of your letter dated March 30, 1989, containing
comments on the subject DRAFT Permit. The Division of Environmental Management will
consider your comments in making its decision on the issuance of the permit. if you feel that your
comments are not addressed in the issued permit, you may request an adjudicatory hearing in
accordance with Chapter 150B of the General Statutes of North Carolina within 30 days of
issuance of the Permit.
If you have any questions, please contact me at [phone].
Sinc&eJJ—
YL
Dale vercash, . E.
Supervisor, NPDES Permits Group
cc: .Mr.,Trevdr Clements (with attachments)
Mr. Rex Gleason (with attachments)
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Tic,
P.O. Box 27687, h'aleigh, North C,-1T'0 ina 27611-7687 Telephone [phone]
An Equal Opportunity Affirmative Action Employer

ALUM NUIVl OM PAINY OF AM;-RICA
w.LG0A U1 L i1INK ?;TTc(_:I1J��'„ �INNlSYLVA,N11, 1`5`191 �..
1989 March 30
Mr. M. Dale Overcash, Supervisor NPDES Group
State of North Carolini?.
Department of Natural Resources and Community Development
Division of Environmental Management 1
512 North Salisbury Street
Raleigh, NC-27611
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Re: Draft NPDES Permit No. NCO004308, Alcoa Badin Works, Stanly County
Dear Mr. Overcash:
On March 9, 1989, Alcoa received the subject draft NODES permit covering
all outfalls at our Badin facility. We have reviewed the draft permit and
believe the following points of issue need to be addressed prior to
finalization by the North Carolina Environmental Management Commission:
1. For Outfall 002, a daily maximum limit of 250 mg/l sulfate is
proposed. We question the use of a secondary drinking water standard
being applied to "the end -of -pipe." Although Badin Lake has a water
supply use designation, our -extensive waste load allocation and mixing
zone study, submitted to your Agency in March, 1988, shows (by both
dye study and actual sampling) that sulfate rapidly dissipates within
10 feet of Outfall 002. We recommend that this waste load study be
cross-referenced and that a daily maximum sulfate limit of 1,000 mg/l
for Outfall 002 be established.
2. Outfall 002 also has a proposed limit for settleable solids (i.e., 0.1
ml/1 daily average and 0.2 ml/l daily maximum) which is believed to be
a carry-over from our present permit. Limiting settleable solids on
an uncontrolled stormwater outfall has limited environmental
significance other than guarding against near outfall siltation.
Historically, silt deposition has not been a problem and we recommend
the settleable solids limits be removed from the permit. We request
that you review our DMR data to substantiate this request.
3. The draft permit incorrectly designates Outfall 009 as "Boiler House."
This outfall discharges small amounts of non -contact cooling water and
stormwater.
4. By reference to Item No. 2, we recommend that settleable solids at
Outfall 009 be addressed the same as at Outfall 002.

Mr. M. Dale Overcash
1989 March 30
Page 2
5. At Outfall 009, a cyanide limit of 0.031 mg/l is presently not
achievable. We cannot agree to a limit that, upon the effective date
of the permit, will instantaneously put us in violation. We request
that a six (6) month compliance schedule be developed and either
incorporated within the final permit or addressed separately by
consent order. The six month time frame.is the minimum time necessary
to physically address the Outfall 009 cyanide issue and should start
after any and all required permits are received. In the interim, the
numerical limit for cyanide should be eliminated from the permit and
shown as "monitor only."
Since the engineered solution may require some type of submerged high
rate diffuser, we request that the final cyanide limit be established
after such system is designed and detailed.
6. Since your Agency has chosen to follow the 1984 EPA ambient water
quality criteria and data base for cyanide, we recommend that,
although not specified in the draft permit, all future cyanide samples
be analyzed using ASTM-D4282-83.
7. The draft permit includes quarterly chronic toxicity testing at
Outfalls 002 and 009, ut;lizing Ceriodophnia. Experience in using
this organism under similar test procedures shows that the test is not
statistically reproducible and that "passing" and hence "failure" of
the test is simply a matter of probabilities, with a bias towards
failure. Although an integrated toxics control strategy using both
effluent toxicity based assessment and pollutant specific procedures
may be required, the toxicity test protocol is overly complex and not
sufficiently advanced to be included as a regulated permit condition.
We, therefore, request removal of this permit condition until a more
consistent and repeatable test method is devised by either your Agency
or EPA.
We appreciate the opportunity to comment and remain hopeful that all
outstanding issues can be mutually agreed upon prior to issuance of the
final permit. If you have any questions, please contact me at
412/553-3131.
Sincerely,
Morgan E. Kommer, Manager
Environmental Control Programs
MEK:mh
cc: C. A. Carter-'Badin Works
R.-P. Wilms - Director, Division
P. R. Atkins - 19
of Environmental Management

1J0J t1�rc
4ater Quality ,,eJiar,al visor
State of NO G-•partme-nt c,f N- tural Resources
and Clommunity Developmtfnt
919 North Main Street
P. 0. Box
Mooresville, Nl. v18ii5 ED0
�St* -.ASTE- -,A R LAG0CIN - A.L.CF !A E A D I d WORKS
Mr. iliea.son-
As 1 mentioned in it:y 198•- Ma,---h 17 letter to you, we have
discontinued pumping the cc.ntents of the captioned and are
now formally rec'uesting of this discharge point, from
our NPL)ES permit.
If any other action is reaui:ed of me to process this
request, pleas_ i nfci-m :ire as goon as pos_ . h, e.
Your quick att_n ir.n to this !liatter• is appreciated.
CiJllrcad A. L .
Mir. hi. cme- r - tt-bur-7r�
Mr . L. i �:u= =e : 1 - ad i is 'wJor 1,s
1-1 r H, E. = I 1 is - En in .Jerks
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State of North Carolina
Department of Natural Resources and Community Development
Division of Environmental Management
512 North Salisbury Street a Raleigh, North Carolina 27611
James G. Martin, Governor R. Paul Wilms
William W. Cobey, Jr., Secretary March 15, 1989 Director
Mr. Morgan E. Kommer, P.E.
Manager, Water and Wastewater
Aluminum Company of America
1501 Alcoa Building
Pittsburgh, PA 15219
Subject: Draft Permit
NPDES No. NCO0043O8
ALCOA - Badin
Stanly County
Dear Mr. Kommer:
In accordance with our telephone conversation on March 13, 1989, please find
enclosed a copy of the analysis that was performed to determine the limitation for
cyanide.
If you have any questions, please contact Mr. David Vogt or me at 919/733-5083.
cc: Mr. Rex Gleason
'�,Mr.-David Vogt
Sincerely,
, ke� -
M. Dale Overcash, P.E., Supervisor
NPDES Group
UES
P.Q. l3ox 27687, Raleigh, North Carolina 27611-7687 Telcphonc 919-733-7015
An Equal opportunity Affirmative Action Employer

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NPD:•ES WASTE LOAD ALLOCATION
PERMIT NO.: Ncoo(��3p
FACILITY NAME: C 0 GL .
Facility Status: PROPOSED
(circle one)
Permit Stat REN�v�r� pLj�CA110N
(circle o NEW
Major
Pipe No: 00 ?s
Design Capacity (MGD):
Domestic (X of Flow):
Industrial (X of Flow): too
Comments:
RECEIVING STREAM: a�r,
Class.
Sub -Basin: O3 -07 - 40
Reference USGS Quad: i IVC
r (please attach)
County: T
Regional Office: As Fa Mo� Ra Wa Wi WS
kirelt •ee)
Requested By: 1`P��CSIoe� L)1 (c1�6
Date:
Prepared By:
Reviewed By:
j
Date: 3 " I
[Modeler
Date
Rec.
# ,
7"0
F� a
Drainage AreInc
2
Avg. Streamflow (cfs):
7Q10 (cfs) '
7Q10 (cfs) ,.,,30Q2 (cfs)
Toxicity Limits: IWC
°b circle c*ne) Acut / Chronic
In -stream Monitoring: 3eC
Parameters
Upstream Location
Downstream Location
Comments:

Permit Number
Facility Name
Type of Waste
Request No.
-- WASTELOAD ALLOCATION APPROVAL FORM ----
RECEIVED
NC0004308 WiNIN OF ENIARONMENTAL MAIIAGEMEN1
ALCOA - PIPE 002
INDUSTRIAL
Status
EXISTING
U,
FEB 1�Oj
Receiving Stream
: BADEN LAKE
MOORESVILLE
Stream Class
: WS- III & B
U-09NAL OFEU
Subbasin
0340708
Ccunty
STANLY
�'tainage Area (sq
mi)
Regional Office
MOORESVILLE
Average Flow
(cfs)
-11equestor
Summer 7Q1
(cfs' Lake
Date of Request
Winter 7Q10
(cfs
Quad
30Q2
(-,-fs)
RECOMMENDED EFFLUENT LIMITS
: Mon Avg Dal Max
Wasteflow (mgd)-
If at--e (mg/l): 25
pH S.U.J': 6 9
Settleable solids (ail/1) : .1 0.2
*Turbidity
''.Temperature
--- --- MONITORING1.3 - - - - - - - - - - - - - - - - -
--- --- --------- --------
Upstream (YIN): Location:
Downstream (YIN): Location,
COMMENTS
DISCHARGE SHALL NOT CAUSE THE TURBIDITY OF THE RECEIVING WATERS TO EXCEED
25 NTU.
ISCHARGE SHALL NOT CAUSE THE TEMPERATURE OF THE R.ECEIVINIG WATERS TO EXCEED
2.9 ABOVE BACKGROUND OR IF NO CASE CAUSE IT TO EXCEED 3 C.
Rezommended by
Reviewed by:
ech. Support Su.-,3ervisor
Regional Supervisor
Permits & Enginee,--ing
..:ter Quality Section Chief
RETURN TO TEC-T-INICAL SERVI-CES 7Y
Date
Date -Z—/G— �)-
Date- Date
Date
r) -i
MAR .4 ;-
A

Facility Name _ C o a. 0� e s 00), Permit # A) U n o i 43 a $�
CHRONIC TOXICITY TESTING REQUIREMENT (QRTRLY)
The effluent discharge shall at no time exhibit chronic toxicity in any two consecutive toxicity tests,
using test procedures outlined in:
1.) The North Carolina Ceriodaphnia chronic effluent bioassay procedure (North Carolina Chronic
Bioassay Procedure - Revised *February 1987) or subsequent versions.
The effluent concentratiog at which there may be no observable inhibition of reproduction or
significant mortality is % (defined as treatment two in the North Carolina procedure
document). The permit holder shall perform quarterl monitoring using this procedure to establish
compliance with the permit condition. The first test will De performed after thirty days from
issuance of this permit during the months of 'F a v . Effluent
sampling for this testing shall be performed at the N ES rmitt final effluent discharge below
all treatment processes.
All toxicity testing results required as part of this permit condition will be entered on the Effluent
Discharge Monitoring Form (MR-1) for the month in which it was performed, using the parameter
13
code TGP3B. Additionally, DEM Form AT-1 (original) is to be sent to the following address:
Attention: Technical Services Branch
North Carolina Division of
Environmental Management
P.O. Box 27687
Raleigh, N.C. 27611
Test data shall be complete and accurate and include all supporting chemical/physical measurements
performed in association with the toxicity tests, as well as all dose/response data. Total residual
chlorine of the effluent toxicity sample must be measured and reported if chlorine is employed for
disinfection of the waste stream.
Should any single quarterly monitoring indicate a failure to meet specified limits, then monthly
monitoring will begin immediately until such time that a single test is passed. Upon passing, this
monthly test requirement will revert to quarterly in the months specked above.
Should any test data from this monitoring requirement or tests performed by the North Carolina
Division of Environmental Management indicate potential impacts to the receiving stream, this
permit may be re -opened and modified to include alternate monitoring requirements or limits.
NOTE: Failure to achieve test conditions as specified in the cited document, such as minimum
control organism survival and appropriate environmental controls, shall constitute an invalid test
and will require immediate retesting(within 30 days of initial monitoring event). Failure to submit
suitable test results will constitute noncompliance with monitoring requirements.
7Q10 cfs
Permited Flow �A_ MGD Recommended by:
IWC%
Basin & Sub-ba in 0 -
Receiving Stream '
County Dat 42.4
"Chronic Toxicity7ij-'eriodaphnia) P/F at %, Fet At , See Part -3) , Condition G-

NPDES WASTE LOAD ALLOCATION
PERMIT NO.: rrcood z.(_� G �
FACILITY NAME: I cllo cam. 6 C', 6U
Facility Status: VG PROPOSED
(circle oM)
Permit Status•
FINEW MOD ] ICATIorr
(circle one) s`�`LeeERWrrEDIV>r'W
Major
Pipe No:
Design Capacity (MGD):
Domestic (X of Flow):
Industrial (X of Flow): 10L
Comments:
RECEIVING STREAM:
Class: -(
Sub -Basin: —0 7 —0
Reference USGS Quad- l a Aj
(please attach)
County:
Regional Office: As� a M, Ra
(circle 6 w+) Wa,Q W i W S
61k D '
Requested By: LJ4
Prepared By:
Reviewed By:
Modeler
Date
Rec.
Drainage Ar
1 Avg- Streamflow (cfs):
7Q10 (cfs)
h Win
Q10 (cfs) 7_30Q2 (cfs)
Toxicity Limits: IWC % (circle case) Acute / Chron'
Instream o C--)?-(—M nitoring:
Parameters
Upstream Location
Downstream Location
o f a:� cue �4_ © -(— a,) `4-14
0
b

Request No. :913 3
Permit Number
Facility Name
Type of Waste
StatTus
ReCei' .Lng Stream
Stream Class
Subbasin
County
Regional Office
f.equestor
Date of Request
.,2uad
WASTELOAD ALLOCATION APPROVAL FORM.---Ays`GNtir�''
NCO004308 RECEIVE::) �
ALCOA - PIPE 009., _ isaism OF iR4 "RwMmAt
INDUSTRIAL
EXISTING
BAD'EN LAKE
: WS-III & B
: 030708
: STANLY
MOORESVILLE
M' f
MO ORESViLLE
r �Eli�ONAI dFFIC6
Drainage Area (sq mi) :
,"Average Flow (cfs) :
Summer 7Q10 (cfs) lake
Winter 7Q10 (cfs) :
30Q2 (cfs) :
RECOMMENDED EFFLUENT
CASE 1
Mon Avg Dal Max.
Wasteflow
(mgd)
Cyanide
(uc/l)-.
31
Fluoride
mg/1 :
24
pH
(--,.U.) :
9
Settleable So ids
(m1/1):
.1 0.2
Oil & grease
(mg/1):
30 60
Turbidity
(NTU):
Temperature
C").
G Pfe. E P
Mon Avg Dal Max
0.1
30
_------------ _ -_ _----------- MONITORING -----
Upstream (Y/h) : Location:
iownstream (Y/N): Location:
COMMENTS
434
'0t01W
6-9
0.2
60
Y.A
32
I: EXISTING DISCHARGE LOCATION.
CASE 2 (PERMIT CONDITION): ALCOA SHALL EXTEND EFFLUENT PIPE 300 FT OUT INTO
B'.'. LAKE. THIS PIPE SHALL EMPLOY A JET PUMP THAT PROVIDES 14:1 INITIF_L
DILUTION TO A FHIJH-PP.TE DIFFUSER LOCATED END-{, F-PIPE AT A DEPTH OF 21 `_'T.
DISCHARGE SHALL NOT CAUSE THE TURBIDITY OF THE RECEIVING WATER TO EXCEED
25 NTU. DISCHARGE SMALL NOT CAUSE THE TEMPERATURE OF WATE: Tt:
EXCEED 2.80C ABOVE BACKGROUND OR IN NO CASE CAUSE IT TO EXCEED 32°C.
4000 EFFLUENT MONITORING ONLY.
Recommended by , Date L-,:2 U /
Reviewed by:
Tech. Support Supervisor _ ,( Date.
Yegio?ial a.ipervisor - /' ! Date _2
Permits & Engineering _ t� Date —L
Watr Quality Section Chief Date
.1 * t;, Aok
-,;-TURNI TO-CHNICAL SERVICES BY MAR 21 1989.

� F '
Facility Name _ � C_ c• cam, 17;� CS tad O Permits �C� G c� on � -3
CHRONIC TOXICITY TESTING REQUIREMENT (QRTRLY)
The effluent discharge shall at no time exhibit chronic toxicity in any two consecutive toxicity tests,
using test procedures outlined in:
1.) The North Carolina Ceriodaphnia chronic effluent bioassay procedure (North Carolina Chronic
Bioassay Procedure - Revised *February 1987) or subsequent versions.
The effluent concentratiog at which there may be no observable inhibition of reproduction or
significant mortality is 16 % (defined as treatment two in the North Carolina procedure
document). The permit holder shall perform quarter lX monitoring using this procedure to establish
compliance with the permit condition. The first t sit w*11 e performed after thirty days from
issuance of this permit during the months of 'ge.b a,) . Effluent
sampling for this testing shall be performed at the NPbES q rmitt final effluent discharge below
all treatment processes.
All toxicity testing results required as part of this pemut condition will be entered on the Effluent
Discharge Monitoring Form (MR-1) for the month in which it was performed, using the parameter
code TGP3B. Additionally, DEM Form AT-1 (original) is to be sent to the following address:
Attention: Technical Services Branch
North Carolina Division of
Environmental Management
P.O. Box 27687
Raleigh, N.C. 27611
Test data shall be complete and accurate and include all supporting chemical/physical measurements
performed in association with the toxicity tests, as well as all dose/response data. Total residual
chlorine of the effluent toxicity sample must be measured and reported if chlorine is employed for
disinfection of the waste stream.
Should any single quarterly monitoring indicate a failure to meet specified limits, then monthly
monitoring will begin immediately until such time that a single test is passed. Upon passing, this
monthly test requirement will revert to quarterly in the months specified above.
Should any test data from this monitoring requirement or tests performed by the North Carolina
Division of Environmental Management indicate potential impacts to the receiving stream, this
penrit may be re -opened and modified to include alternate monitoring requirements or limits.
NOTE: Failure to achieve test conditions as specified in the cited document, such as minimum
control organism survival and appropriate environmental controls, shall constitute an invalid test
and will require immediate retesting(within 30 days of initial monitoring event). Failure to submit
suitable test results will constitute noncompliance with monitoring requirements.
7Q10 cfs
Perrnited F(ow A—_ MGD Recommended by:
ItiVC% Aj 4—
Basin & Sub-ba in --
Receiving Stream
County- L— - Dat' _-._-
v
`Chronic Toxicity eriodaphnia) P/F at%, n-FeL iM , See Part, Condition U .

AICIOCA—
rn 101 , OX vvt.olL
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P.O. BOX S.V6
HAM-N, NOH'H-1 CAnC)LINA 28009
1988 March 10
Department of NRCD
Division of Environmental Management
P. 0. Box 27667
Raleigh, North Carolina 27611
Attention: Mr. M. Dale Overcash
NPDES Permits Group
Gentlemen:
Ref: Renewal of NPDES Permit No. NC0004308
CERTIFIED MAIL
RETURN RECEIPT
� �o�oe •� � t x
,r.. !_ C C; l A
Proposed limits for Fluoride and Cyanide from Discharge 009
cannot be met at this time using any available technology. My
letter to you, dated 1987 August 03, indicated.our plans to
performed a Waste Load Allocation Modeling Study on NPDES
Discharge 009 for Fluoride and Cyanide. The study was
performed in late 1987.
The study recommended the the following permit limits:
1'. Discharge 009: Cyanide (Free) 2.15 mg/I
Fluoride 774 mg/1
2. Discharge 002: Sulfate 250 mg/I
We propose that the above limits for cyanide and fluoride
for 009 be -incorporated in our NPDES.Permi-.t.
We.also propose that monitoring for sulfate in:002 be dropped
from our permit in view of our historically low emission rate
and the above recommended limit for -that parameter.
Please review the attached final report from FTN Associates.
If you do not concur with the above recommendations or the
conclusion's of this study, please notify me at once.
Very truly yours,
P.
Conrad A. Carter, P. E.
Manager, Environmental Protection
cc: Mr. J. Thurman Horne, DEM, Mooresville (Letter only)
T. W. Baugh/H. E. E1 l is--Alcoa('Letter only)
P. R. Atkins/M. E. Kommer-lab, Pgh Office
File:NPDESRAL

DATE
10/12/87
10/12/87
10/13/87
10/19/87
10/20/87
10/20/87
10/21/87
10/22/87
Tt[b+e-4 r. Concentrations of sulfate found in 002 effluent and
fluoride and cyanide found in 009 effluent.
DATE
10/12/87
10/12/87
10/13/87
10/19/87
10/20/87
10/22/87
TIME
0825
1610
0715
0820/1710
0850/1725
0900/1735
0845/1612
G750/1540
ALCOA BADiN WORKS
NPDES DISCHARGES #009 & #002
ANALYSIS OF WATER SAMPLES
12.22 OCTOBER, 1987 FIELD STUDIES
#002 Outfalt Water Quality Samples
TIME
0830
1630
0730
0925/1525
0928
08205/1420
TYPE
Grab
Grab
Grab
Composite
Grab
Composite
4009 Outfalt Water Quality Samples
SULFATE
Cmg/ U
13.6
14.6
14.9
33.7
22.9
3-12
FLOW
(mgd)
0.100
0,067
0.067
TOTAL.
FREE
FLORIDE
CYANIDE
CYANIDE
FLOW
TYPE
(mg/0
(mg/L) ..
OWL)
(mgd)
Grab'
28.3
0.704.
0.232
0.053
Grab
29.1
0.797
0.195
0.053
Grab
29.2
0.844:
0.221
0.053
Composite
26.5
D.620
•0.047
Composite
26.7
0.580
0.047
Replicate
27.2
0.630'
0.047
Composite
27.9
0.560
0,047
Composite
25.7
0.500
0.047
4-34

APre'.Idix I
MEMORANDUM
TO: Greg Thorpe
FROM: David Williams 667J
RE: Cyanide removal at Alcoa
DATE: March 29, 1989
I have reviewed several EPA publications and other
literature regarding free and complexed cyanide removal from
wastewater in the metal fir_ishing industry. Mr. Morgan Kor^mer of
Alcoa, in his letter dated February 27, 1989, was correct when he
stated that the EPA has determined that'12 mg/1 is the total
cyanide level achieveable by application of the best demonstrated
available technology (BDAT) for -cyanide -containing process
wastewaters and sludges from the metal finishing industry. These
wastestreams typically contain total cyanide in excess of 1000
mg/1- and are listed as hazardous wastes. Our concern in this
instance is not process way-ewater containing 1000 mg/l cyanide
but, rather, stormwater runoff containing 2 mg/l cyanide
resulting from spent potliner leachate: Spent potliner
leachate is not currently regulated as hazardous wastes, so
t,ie BDAT Mr. Kammer mentioned does not apply.
EPA's Development Document for Effluent Limitations
Guidelines, and Standards ---':or the Metal Finishing Point Source
Category suggests that effluent levels below 100 ug/l are
achieveable for wastestreat-ns containing moderate influent levels
of total cyanide. Two methods are mentioned as being useful for
treating complexed cyanide wastes. These methods are cyanide
precipitaion and cyanide oxidation by ozone with -ultraviolet (UV)
radiation.
Cyanide precipitation involves adding zinc sulfate or ferric
sulfate to the wastestreams to form zinc ferrocyanide or ferro
and ferricyanide complexes -,which can be precipitated by raising
the pH to 9.0. Cyanide precipitation can achieve effluent total
cyanide concentrations well below 150 ug/l, although the
precipitated sludge may need to be treated as a hazardous waste.
This process is common in the aluminum industry.
Cy;1nidc oxidation by c-_one ,pith UV radiation has been
demonstrated successfully -for oxidizing iron-complexed cyanide
wasto-s to the less toxic c•--ana_e form. This cyanate could, then,
be fL,.r.her oxidized to car-�n (_oxide and ammonia thro::gh further
exposu_c to ozone, ali:haug_-_ this `uather ozonation may be
cxpenE;.yve. more economical- a_Uroacn would bQ to further oxidize
the cyanate biologicall, a -..a neutral pH. The UV radi Lion aids

'frePIX)c c.2-
in uncomplexing the cyanide complexes to free the cyanide for
ozonation. This process has been demonstrated to achieve total
cyanide concentrations less than 100 ug/l.
EPA's Development Document for Effluent Limitations
Guidelines, and Standards for the Nonferrous Metals Forminq and
Metal Powders_ Point Source Category suggested that cyanide
oxidation by hydrogen peroxide is also effective in treating
complexed cyanides. This process involves heating the
cyanide -bearing wastewaters to 49 to 54 degrees C and adjusting
the pH to approximately 11. A formaldehyde solution is added
followed by the addition of.a hydrogen peroxide solution to
oxidize the cyanide to cyanate. Total cyanide concentrations can
be reduced to below 100 ug/l with this process.
It is evident that there are processes available to Alcoa to
reduce the concentration of cyanide in their stormwater
discharge. Alcoa should be asked to give further consideration to
these processes in an attempt to solve their cyanide problem.
'I am willing to discuss my findings with anyone from Alcoa
or DEM if you need me to.

CERTIFIED BIOLOGICAL LABORATORIES
Category/ Parameter
DEM 3/13/89
Laboratory Acute Chronic Aquatic Population Survey Algal/ Plant
Biological Monitoring, Inc.
Ceriodaphnia dubia,
Ceriodaphnia dubia,
Fish,Macroinvertebrate,
Selenastrum capricornutum
P.O. Box 184
Daphnia pules,
Daphnia pulex,
A1gae,Macrophyte,
Blacksburg Va. 24063
Mysidopsis bahia,
Fathead minnow
Zooplankton
Fathead minnow
Phone no. [phone]
Lab Supervisor Mark A. Collins
13121ck & V4alill
1)uphuin lailc x
C4rictth�hholin dul>in
110 Wcst Walker Avenue
Asheboro N.C. 27203
Phone no. [phone]
Lab Supervisor J. Allen Spivey
Burlington Research, Inc.
Ceriodaphnia dubia,
Ceriodaphnia dubia
P.O. Box 2481
Daphnia pules,
Burlington N.C. 27215
Fathead minnow
Phonc no. [phone]
Lab Supervisor Rick Diehl
CH2M Hill
P.O. Box 1647
Gainesville Fla. 32602
Phone no. [phone]
Lab Supervisor John R. Skellcy
Ceriodaphnia dubia,
Daphnia pulex,
Mysidopsis bahia,
Fathead minnow,
Menidia beryllina,
Cyprinodon variegatus
Ceriodaphnia dubia,
Mysidopsis bahia,
Fathead minnow,
Menidia beryllina,
Cyprinodon variegatus
Chemical and Environmental Technology
Ceriodaphnia dubia,
Ceriodaphnia dubin
102A Woodwinds Industrial Court
Daphnia pulex
Cary N.C. 27511
Phone no. [phone]
Lab Supervisor Kenneth Jesneck
City of High Point Central Lab Services
Ceriodaphnia dubia
Ceriodaphnia dubia
P.O. Box 230
High Point N.C. 27261
Phone no. [phone]
Lab Sulkrvi.<ir Thaiwts 11. Core.
1

Laboratory
CERTIFIED BIOLOGICAL LABORATORIES
Category/ Parameter
Acute
Chronic
DEM 3/13/89
f
Aquatic Population Survey Algal/ Plant
CP&L Environmental Services
Ceriodaphnia dubia,
Ceriodaphnia dubia
Fish,Macroinvertebrate,
Rt.1 Box 327
Fathead minnow
Algae,Macrophyte,
New Hill N.C. 27562
Zooplankton
Phone no. [phone]
Lab Supervisor Richard C. Yates/ G. Booth
Duke Power Co.
Ceriodaphnia dubia,
Ceriodaphnia dubia
Fish,Macroinvertcbrate,
Production Environmental Services, Rt.4 Box 531
Daphnia pulex
Algae,Maerophyte,
Huntersville N.C. 28078
Zooplankton
Phone no. [phone]
Lab Supervisor Gene Vaughn
Eckenfelder Inc.
Ceriodaphnia dubia,
Ceriodaphnia dubia,
227 French Landing Drive
Daphnia pulex,Daphnia
Fathead minnow
Nashville Tenn. 37228
magna,
Fathead minnow
Phone no. [phone]
Lab Supervisor Dr. Richard Mirenda
Environmental Testing, Inc.
Ceriodaphnia dubia,
Ceriodaphnia dubia,
54 Ravenscroft Drive
Daphnia pulex
Daphia pulex
Asheville N.C. 28801
Phone no. [phone]
1 Lab Supervisor Paul Smith
! Enwright Laboratories, Inc.
s
Ceriodaphnia dubia,
Ccriodaphnia dubia
25 Woods Lake Road
Daphnia pulex,
Greenville S.C. 29607
Mysidopsis.bahia
Phone no. [phone]
Lab Supervisor Robert Kelly
James R. Reed & Associates, Inc.
Ceriodaphr" dubia,
Ceriodaphnia dubia,
813 Forrest Drive
Daphnia pulex,Daphrda
Fathead minnow
Newport News Va. 23606
magna,
Mysidopsis bahia,
Phone no. [phone]
Fathcad minnow,
Lab Supervisor Elizabeth Christoff
Cyprinodon variegatus,
�O
L
H
1

Laboratory
CERTIFIED BIOLOGICAL LABORATORIES
Category/ Parameter
Acute
Chronic
DE.M 1/13/89
Aquatic Population Survey Algal/ Plant
Normandeau Associates, Inc.
Ceriodaphnia dubia,
Ccriodaphnia dubia
P.O. Box 1393
Daphnia pulex,Daphnia
Aiken S.C. 29802
Magna,
Fathead minnow
Phone no. [phone]
Lab Supervisor Kathleen E. Trapp, PhD
Research and Analytical Labs, Inc.
Ceriodaphnia dubia,
Ceriodaphnia dubia
P.O. Box 473
Daphnia pulex
Kernersvillc N.C. 27284
Phone no. [phone]
Lab Supervisor James M. Cheshire
Shealy Environmental Services, Inc,
Ceriodaphnia dubia,
Ceriodaphnia dubia
400 Graymont Avenue
Daphnia pulcx,
Columbia S.C. 29205
Fathcad Minnow
Phone no. [phone]
Lab Supervisor Richard L. Shealy
The Advent Group, Inc.
Ceriodaphnia dubia,
Ceriodaphnia dubia,
201 Summit View Dr., Suite 313
Daphnia pulex,
Fathead minnow
Brentwood Tenn. 37027
Fathead minnow
Phone no. [phone]
Lah Supervisor Carl M. Crnnc
3

Paterg k
resources consultants
ASSOCIATES LTD. 3 INNWOOD CIRCLE • SUITE 220 • LITTLE ROCK, AR 72211 • PHONE [phone]
17 February 1989
J. Trevor Clements
Environmental Modeling Supervisor
Division of Environmental Management
Water Quality Section
P.O. Box 27687
Raleigh, NC 27611
RE: ALCOA - Badin NPDES Permit No. NCO004308
Dear Mr. Clements:
Enclosed for your review are the jet and plume dilution computations and the
diffusion model results for the mixing zone for Outfall 009 for the referenced
permit.
If you have any questions or require additional information, please call.
Kindest regards,
FTN ASSOCIATES, LTD.
Denn.ts*MFo
is E. Ford, PhD, 2P.E.
Principal Hydrologist
ms
cc: C. Carter, ALCOA - Badin
M. Kommer, ALCOA - Pittsburgh

17 February 1989
BADIN OUTFALL 009: PLUME DILUTION - 300 FT OUT
Problem: Calculate pure plume dilution of effluent from
Badin Outfall 009 assuming period of record discharge
out 300 ft from current location
(depth = 21 ft = 6.4 m).
Approach: Table 9.3, Fischer et al. (1979), round plume:
Dilution = µ/Q
µ = Volume flux = (0.15 ± 0.015) B1/3Z5/3
B = go'Q
Z = Depth of water column
g , =.g ( Pambient - Peffluent )
0
Pambient
Q = flow rate
P = density
Solution
Q = 0.08 x 106 gal * day * ft3 * m3
.day 86400 sec 7.48 gal (3.28)3ft3
= 3.51 x 10--3 m3/sec
Assume ambient temperature = 25°C, effluent temperature = 260C
go' = 9.8 m/sec2 x (997.07 kgfm3 - 996.81 kq/m3)
997.07 kg/m3
= 2.61 x 10-4 m/sec2
B1/3 = (2.61 x 10-4m/sec2 * 3.51 x 10-3 m3/sec)1/3
= 9.71 x 10-3
µ/Q = 0.15 9.71 x 10-3 6.4 5/3 = 9.15
3.51 x 10-3 m3/sec

17 February 1989
BADIN OUTFALL 009: JET DILUTION - 300 FT OUT
Problem: Calculate pure jet dilution of effluent from
Badin Outfall 009 assuming sump flow of 600 gpm pumped
out 300 ft from current location
(depth = 21 ft = 6.4m).
Approach: From Fischer et al. (1979) Table 9.2 for a
round jet:
Dilution = µ/Q = 0.25 (Z/lQ)
Z = Depth of water column
1Q = Characteristic length scale = Q/M2
Q = Flow rate
M = Momentum flux = QV
V = Jet exit velocity
Solution:
Q = 600 gal/min * min x ft3 * m3
60 sec 7.48 gal (3,28)3ft3
0.038 m3/sec
V = 10 ft/sec (minimum for classification as jet)
3.05 m/sec
M = 0.038 m3/sec (3.05 m/sec) = 0.110
M' = 0.340
I = Q/MZ = 0.038 m3/sec / 0.340 = 0.11
µ/Q = 0.25 (6.4/0.11) = 14.6

Badin Outfall 009 Diffusion Modell Results
Radial Distance (ft) for
Scheme O(mad) C(ma/1) 22 ua/1@96 hrs 5 uq/1@24 hrs Comment
Existing 0.15 0.51 50 -- Shore prevents radial
Conditions 0.08 0.37 -- 86 diffusion; predicted
concentrations doubled
Plume depth 21 ft, 0.15 2.15 98 ---- Increased Q, decreased C
300 ft from shore 0.08 1.80 -- 192 by plume dilution factor
of 4.5
Jet depth 21 ft, 0.15 2.30 100 -- Increased Q, decreased C
300 ft from shore 0.08 1.80 -- 199 by jet dilution factor
of 7.0
1 Hoopes and Harleman (1967) as presented in EPA/600/6-85/0026b (1985) with
molecular diffusion (10-6 cm2/sec).

water
ter reeourres consuitants
ASSOCIATES LTD. 31NNWOODC[RCLE 0 SUITE220 6 LITTLE ROCK, AR 72211 * PHONE [phone]
FACSIMILE TRANSMITTAL COVER SHEET
Date -
To
2 1. 21 Z
VJCL-k-t-nv-a-.h i 004-w
From:
FTN ASSOCIATES, LTD,
Little Rock, AR
Fax - [phone] Jeol, 1041 '9
*
S40,
Project No...
Pages in this transmittal (including this cover sheet).-- I L

It
water resources conSUitants
ASSOCIATES LTD. 3 INNWOOD CIRCLE • SUITE 220 + LITTLE SOCK, AR 72211 • PHONE [phone]
9 February 1989
J. Trevor Clements
Environmental Modeling Supervisor
Division of Environmental Management
Water Qualityry Section
P.O. Box 27687
Raleigh, NC 27611
RE: ALCOA - Badin NPDES Permit-Nb. NCO004308
Dear Mr. Clements:
Enclosed for review is our revised analysis of the mixing zone for Outfall 009
for the referenced permit. In this analysis, we considered three alternatives and
tried to incorporate all of the State's concerns from our initial submittal. We look
forward to discussing these alternatives with you on 14 February 1989.
K.indes regards,
FTN OCIATES, LTD
Dennis E. Ford, PhD, P.E.
Principal Hydrologist
ULS
cc: C. Carter, ALCOA - Badin
M. Kornmer, ALCOA - Pittsburgh

_ = .
ALCOA -Badin Mixing Zone Alternatives
1.0 Objective - ALCOA needs to discharge an average flow of 0.08 MGD
from Outfall 009 with a maximum cyanide concentration of 2.3 mg/l into
Badin Lake
2.0 Effluent Characteristics
2.1 Flow - Assumed to increase with storm water nlnoff
a) Historical data (1983-88)
Average = 0.078 MGD
Maximum observed = 0.302 MGD
90th percentile = 0.15 MGD
b) Permitted flow = 0.5000 MGD
c) Flows assumed for modeling
- Average (Chronic condition - 96 hr average) = 0.08 MGD
- Maximum (Acute conditions - 24 hr average) = 0.15 MGD
2.2 Cyanide concentrations - It is assumed that high cyanide
concentrations are in response to storm water runoff and therefore
are of short duration
a) Historical data (Mar 1982 - Jul 1988)
Total Average = 0.69 mg/l (47 observations)
Maximum = 2.3 mg/l
Free Average = 0.09 mgfl (32 observations)
Maximum = 0.58 mg/1
b) Permit Iimits required to avoid exceedences
1) T otal Cyanide
o Monthly average = 1.8 mg11
- Based on average plus 2 standard deviations
- Requires 360 to 1 dilution to meet chronic
toxicity
o Daily maximum = 2.3 mg/l
- Based on maximum observed and average plus
3 standard deviations
z

- Requires 105 to 1 dilution to meet acute
toxicity
2) Free Cyanide
o Monthly average = 0.37 mg/l
- Based on average plus 2 standard deviations
- Requires 74 to 1 dilution to meet chronic toxicity
o Daily maximum = 0.58 mg/1
- Based on maximum observed
Requires 26.4 to 1 dilution to meet acute
toxicity
3.0 Constraints
3.1 Acute toxicity limit (22 ug/1) needs to be met at end -of -pipe or
within a small zone of initial mixing (ZID),
3.2 ZID must be within 10% of the distance from the outfall to the
edge of regulatory mixing zone
3.3 Chronic toxicity limit (5 ug/l) needs to be met at edge of regulatory
mixing zone
3.4 State would prefer discharge to he off -shore
3.5 Recommendations need to be consistent with dye data
4.0 Original Recommendations
4.1 Recommendations
Cyanide Limits - 2.15 mg/l (Free)
Mixing Zone = 500 ft, ZID = 50 ft
Dilution - 430 to 1
4.2 Justification
4.2.1 Wind generated currents and turbulence and pool
fluctuations supply sufficient dilution water to mixing zone.
4.2.2 Measured cyanide concentrations in mixing zone under
critical conditions support discharging under existing
operating procedures.
4.3 State's Objections
4.3.1 Use of ZID which is now acceptable
2

4.3.2 Some dye data indicated dilutions less than 430 to 1
4.3.3 Proximity of discharge to swimming area
5.0 Alternatives
5.1 Status quo
5.1.1 Description - Outfall ON would remain as is
5.1.2 Proposed Limits
Cyanide (Free) -
Daily maximum = 510 ug/1(0.51 mg/1)
Monthly average = 370 ug/l (0.37 mg/1)
Mixing Zone = 300 ft, ZID = 30 ft
Dilution - 100 to 1, 22.7 to 1, respectively
5.1.3 Justification/Supporting Documents
a) Dye data supports a dilution fo 22 to l in ZID and I10
to 1 in mixing zone with one exception (Figure 1)
b) Modeling using point source diffusion indicates
maximum concentrations of
Scenario Acute Chronic
(Flow .gnc) 24 hrs 2 brs
0.15 MGD/510 ug/I 22 ug/i at
so i't
0.08 MGD/370 ug/I -- 5 u /l at
86 ft
5.1.4 Advantages
a) Dye data supports results with one exception
b) Mixing zone and ZID are smaller than in original
recommendation (Section 4.0)
c) Free criteria is met by historical data with 2 exceptions
(0.58 mg/l in Mar 83 and 0.54 mg/l in Jun 83)
3

r-. a
5.2 300 ft extension
5.2.1 Description - Extend existing outfall straight out 300 ft
into approximately 21 ft of water at normal pool (Figure 2)
5.2.2 Proposed Limits
Cyanide -
Daily maximum = 2.18 mg/l
Monthly average = 2.25 mg/l
Mixing Zone = 300 ft, ZID = 30 ft
Dilution - 450 to 1, 99 to 1, respectively
5.2.3 Justification/Supporting Documentation
a) Initial dilution as plume rises in 21 ft of water is 9 to 1
based on equations in Fischer et al, (1979) - Mixing in
Inland and Coastal Waters. One half of this dilution
(4.5 to 1) was assumed for modeling to be conservative,
b) Dye data supports a dilution of 99 to 1 in ZID and 450
to 1 in MZ with one exception when the initial dilution
from the plume is included. These dilutions would
result in limits of 2.18 mg/I for acute conditions and
2.25 mg/l for chronic conditions.
c) Model results using the diffusion model indicate
maximum concentrations of
Scenario Acute Chronic
(Flow/cmc) 24 hrs 96 hrs
0.15 MGD/2.15 mg/1 22 ug/I at --
98 ft
0.08 MGD/1.8 mg/l -- 5 ug/l at
192 ft
5.2.4 Advantages
a) Outfall is off shore. Chronic criteria met at shoreline.
b) Dye data supports recommendations assuming an initial
dilution of 4.5 to 1 because, of local water depth and
buoyancy forces in plume.
e) Mixing zone and ZID smaller than previous
,recommendations
4

d) Proposed limits for free cyanide are met by historical
data
5.2.5 Concerns
a) Mixing would not be as efficient as shore discharge
because effluent would not be exposed to surface where
majority of turbulence is concentrated (i.e. area of
active mixing).
h) Extending pipe into lake would raise public awareness
of outfall. Currently it looks like a normal storm drain.
c) initial mixing may be less than assumed because of
decreased buoyancy forces resulting from heat transfer
in submerged effluent, pipe.
5.3 High Rate Diffuser
5.3.1 Description
a) 009 effluent would flow into sump or storage basin at an
average rate of 0.08 MGD (56 gpm). Sump could be
located near shoreline or preferably on Alcoa property
near manhole where 009 samples are collected.
b) Effluent could either be stored and discharged
continuously to lake. Discharge would be controlled.
c) The discharge would be pumped through a smaller pipe
(e.g. -4 in) inserted into the existing pipe. The existing
pipe would be used for overflow from large storms.
d) A diffuser would be located —300 ft off shore in 21 ft of
water. The jets would be directed upward and an initial
dilution of 14.0 could be expected.
5.3.2 Proposed Urnits
Cyanide -
Daily maximum = 3.39 mg/l
Monthly average = 3.50 mg/I
Mixing Zone = 300 ft, ZID = 30 ft
Dilution - 700 to 1, 154 to 1, respectively
19

5.3.3 Justification/Supporting Documentations
a) 7 to I dilution in jet was assumed even though a 14 to 1.
dilution was predicted from equations in Fischer et al.
1979. This dilution coupled with the diffusion dilution
from the dye studies results in a total dilution of 700 to
1 for the mixing zone and 154 to 1 for the ZID.
b) Dye studies support dilution with same exceptions as in
other alternatives
c) ModeI results using the diffusion model indicate
maximum concentrations of
Scenario Acute Chronic
0.15 MGD/2.3 mg/1 22 ug/1 at 100 ft
0.08 MGD/1.8 mg/I S ug/l at
199 ft
5.3.4 Advantages
a) Mixing zone is small and off shore away from human
Contact
b) Initial mixing is more certain because of jet entrainment
c) No problems with human health criteria
6.0 Recommendations
6.1 Cyanide limits should be based on free cyanide because all criteria
developed by EPA were based on acid soluble cyanide, not total
cyanide.
6.2 Continue discharging through existing outfall with free cyanide
Iminits of:
Daily Maximum = 0.51 mg/I
Monthly Average = 0.37 mg/1
for a 300 ft mixing zone,
6.3 Extend outfall 300 ft and into lake and use a jet diffuser to achieve
initial mixing. Ilis alternative would require the addition of
pumps and small diamter pipe for the jet. Permit limits would
need to be:
6

Daily Maximum = 1.8 mg/l
Monthly Average = 2.3 mg/I
and the mixing zone would be a 300 ft radius around the diffusor,

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3 InnwOod Cifcle . Suite 220 • Gtt+e Rock. AR 7221 t • 15C1J 225.7779

DIVISION OF ENVIRONMENTAL MANAGEMENT
June 27, 1988
TO: Arthur Mouberry
THRU: Trevor Clements
Steve Tedder A.
FROM: David Vogt
SUBJECT: Review of Alcoa's Comments Regarding the Limits and Monitoring
Requirements Recommended in the Renewal of NPDES Permit# NCO004308
(Stanly Co.)
Per your request, Technical Services has reviewed Alcoa's comments
concerning their existing monitoring requirements as well as the proposed
fluoride and cyanide limits for pipe 009. Regarding the comments outlined in
Alcoa's letter of 3-27-87 (Appendix 1), Technical Services recommends that all
existing monitoring requirements remain in effect except for pipe 004. For
the 004 discharge, we agree with their request.
Regarding Alcoa's letter of 3-10-88 (Appendix 2), Technical Services
recommends the following limits:
Pipe 009(011 `7 011_
Cyanide: The latest WLA (see Appendix 3) had a cyanide limit of 5 ug/l
(the NC Water Quality Standard). Technical Services recommended
the standard because we had no information on the dilution
properties of Badin Lake in the cove area where the outfall is
located. Since the time of the analysis for the WLA, Alcoa has
hired a consultant: FTN Associates, Little Rock, AR. In October
of 1987, FTN performed a field survey in the portion of the cove
near the outfalls of pipe 002 and 009 (see Appendix 4). A dye
study was conducted during the survey in order to ascertain the
mixing characteristics of Alcoa's effluent into the cove.
FTN then combined the results of this study (mixing due to
dispersion, currents generated from wind fetch, and fluctuating
lake levels) with predictions from a theoretical dispersion model
to recommend the following limits for pipe 009 (see Appendix 2):
Cyanide (free): 2.15 mg/1 (2150 ug/1)
Fluoride . 774.00 mg/1
In recommending the cyanide limit, FTN used EPA criteria for
estimating a 50 ft zone of initial dilution (ZID) as well as a
500 ft boundary to protect at the chronic level (i.e., from the
outfall to 50 ft, no limit would apply, from 50 ft to 500 ft the
acute level of 22 ug/1 would apply, and at 500 ft and beyond the
5.0 ug/1 chronic level would apply - see Appendix 5). However,

Fluoride:
the State of North Carolina does not presently recognize ZIDs in
our regulatory framework (see NC Administrative Code Section:
15 NCAC 2B .0204 for a narrative description of mixing zones).
Therefore, Technical Services recommends that the 22 ug/1 acute
level be applied as a whole -pipe effluent limit.
Using the NC Water Quality Standard of 5 ug/l, the dilution ratio
necessary to protect at the chronic level is 22/5.0, or 4.4 to 1.
Review of the last set of dye concentration levels taken near -field
to the pipe 009 outfall (29 hours after dye injection) shows that
this dilution ratio is met approximately 10 ft from the outfall
(Appendix 6.1). However, Technical Services recognizes that a 10
ft radius from the outfall may not adequately represent a mixing
zone. Moreover, since it appears that FTN did not carry out the
dye study until equilibrium conditions were met, we feel that it
is best to remain conservative, and hence, we are recommending a
50 ft mixing zone. This means that Alcoa will be required to
meet the 4.4 to 1 dilution ratio 50 ft from their outfall. Alcoa
will not be required to actually sample at the 50 ft boundary we will credit the 4.4 to 1 dilution in their whole -effluent
toxicity limit; this can be calculated by x*4.4=100, or x=23%
(Appendix 7).
Furthermore, even if we did recognize ZIDs, this type of mixing
zone would not be appropriate because of the recreational swimming
that occurs in this portion of the cove. Although FTN states
that historical data from outfall 009 exceeded the EPA human
health criteria of 200 ug/1 for cyanide only 15 percent of the
time (Appendix 5.2), we are concerned about the severity of any
individual violations and the tendency of the effluent to plume
toward the swimming area. In addition, using FTN's maximum
observed input of 2,200 ug/1 (Appendix 5.2) or their proposed
cyanide limit of 2,150 ug/1 (Appendix 2), and applying the 5 to 1
dilution predicted near the outfall (Appendix 6.1), we obtain
respective cyanide concentrations of 440 ug/l and 430 ug/l,
which are more than double the 200 ug/1 human health criteria.
Since Division of Wildlife field personnel have reported that
during hot weather they have observed crowded bathers moving out
of the designated swimming area and going into the outfall region
(the roped -off swimming area is about 100 yards from the outfall),
this is of real concern. Also, FTN's report depicts the direction
of the dye plume at 30 hours into injection (the longest -running
view we have of dye movement), moving through the swimming area
(Appendix 6.2) with a dilution ratio of 39 to 1 edging into the
roped -off area (this is in contrast to FTN's assertion of a 100
to 1 dilution ratio -see Appendix 5.2).
Current literature values (Appendix 8) support the use of a Final
Acute Value (FAV) for fluoride of 47.9 mg/1 (non -trout waters).
Using the North Carolina Water Standard for fluoride of 1.8 mg/l,
a required dilution ratio to protect at the chronic level can
also be calculated for fluoride. Thus the required dilution for

fluoride being discharged from pipe 009 is 47.9/1.8, or 27 to 1.
Referring to -Appendix 6.1 again, it can be seen that this occurs
approximately 40 ft from the outfall. Hence, the 50 ft mixing
zone proposed for cyanide can also be applied for fluoride.
However, calculating a whole -effluent limit from fluoride would
yield x*27=100, or x=4% (Appendix 9). Since we are unsure of
the true mixing characteristics of the cove, and since cyanide is.
more toxic than fluoride, it is recommended that DEM be conservative
and use the 23% calculated above (FTN also followed this logic -
refer to Appendix 10). Therefore, the following limits* are
recommended for pipe 009:
cyanide: 22.0 ug/1
fluoride: 47.9 mg/1 �� b
chronic toxicity testing requirement (quarterly): no significant
mortality or observable inhibition of reproduction of Ceriodaphia
at an effluent concentration of 23%
*existing limits for other pollutants not being contested by
Alcoa shall remain as stated on draft permit
Pipe 002
In regard to pipe 002, there is no FAV for sulfate so we cannot
calculate a required dilution -ratio based on acute/chronic limits. Thus,
in the absence of useable information on dilution ratios (FTN conducted
an abbreviated dye study at pipe 002; they terminated injection after only 6
hours), Technical Services recommends that the above limit of no chronic
toxicity at 23% also apply to pipe 002.. Since independent laboratory tests
demonstrate that phenols have been present in pipe 002 (see Appendix 11), and
because the receiving waters are classified WS-III, it is recommended that
Alcoa monitor pipe 002 for phenols. We do agree with maintaining the existing
sulfate limit of 250 mg/l.
Please contact myself or Trevor if you have questions regarding these
comments and/or recommendations.
JDV/jdv
Attachments
cc: Ken Eagleson, DEM
Thurman Horne, DEM
W. E. Venrick, DHS
Q-Alcoa WLA File
Central Files

APPENDIX 1.1
P.0. b10„
f-si�,L�l�l, i�-IG";��;; `.;��.I�.GLI�!n �%•i.1C°°��
1987 March 27
r
MAR
pn 19E�
State of North Carolina
Department of Natural Resources & Community Development
512 North Salisbury Street
Raleigh, North Carolina 27611
Attention: Mr. R. Paul Wilms, Director
Division of Environmental Management
Gentlemen:
Reference: Renewal of NPDES Permit No. NC0004308
We would like to address your proposed changes to existing parameters in
this letter. Comments on proposed new parameters will follow in another
.letter.
Over the last several months, we have been assimilating and graphing our
NPDES sampling data back through 1981. While it has taken a tremendous
amount of time to accomplish, we believe it to be critical to our, and
your, understanding of the data. In general, we feel that the data
collected and presented here verifies that we can substantially reduce our
monitoring and still protect our environment. In this time of increased
competition in our market, we must do only the monitoring that is
absolutely required and make it count!
We appreciate your patience with us on preparing this data. Attached
please find our comments on the existing proposed parameters.
Very truly yours,
CONRAD A. CARTER, JR., P.E.
MANAGER, ENVIRONMENTAL PROTECTION
CACJr:rbh
cc: J. L. Fox/T. W.'Baugh (Letter & Comments only)
P. R. Atkins/M. E. Kommer (All)

APPENDIX 1.2
PAGE 1
CON701ENTS ON PROPOSED NPDES PERMIT NO. NCO004308 - EXISTING PARAMETERS
Discharge 002 -- Storm Drain ,Boiler Blowdown, Non -Contact Cooling of
Air Compressors
1, Terra _tune
A. Measurement Freer. zenca
We have been monitoring our effluent monthly under our old
permit. You have proposed that we monitor our effluent upstream
and downstream weekly. If you will refer to Attachment no. 1,
you will see that our discharge temperature closely follows the
ambient air temperature and is very consistent from
year--to-year. With a river flow of 6000 MGD and a discharge flow
of 0.5 MGD, a 2.80C rise in the Yadkin River's ambient water
temperature would require a water discharge temperature of
33,6000C! This is impossible. We cannot see any merit to
increasing our measurement frequency. Accordingly, we propose to
monitor Discharge 002 for temperature on a monthly basis.
B. Sampling Location
We have been monitoring our effluent only under our old permit.
You have proposed that we monitor effluent, upstream and
downstream. Since this discharge enters Badin Lake in a 0.5 mile
long cove with no decernable flow pattern, we cannot understand
how an up/downstream measurement can be made. We propose to
collect a "Downstream" sample between the effluent and the main
river. The sample would be taken from the bank at a point 50
yards from the effluent.
2. Flow Discharge Limit
You have proposed that the permissible average flow limit be reduced
from 0.5 to 0.232 MGD. As you can see on Attachment #2, the flow is
typically less than 0.200 MGD but that we have exceeded 0.232 a total
of ten (10) times since 1981. Please note that it is primarily a
storm water discharge and, as such, we have no control over its flow
rate. Accordingly, we propose that all flow limitations be removed
from this discharge.

APPENDTx 1.3
PAGE 2
COMMENTS ON PROPOSED NPDES PERMIT NO. NC0004308 - EXISTING PARAMETERS
Discharge 003 -- Lagoon
1. Flow
A. Measurement F=ic nqy
We have been reporting weekly under our old permit. You have
proposed daily reporting. If you will refer to Attachment #3
(copies of our flow charts for the last six (6) months of 1986),
you will note that the flow is very consistent except during
rainy periods. It appears to us that weekly reporting is very,
representative of the lagoons daily performance. Also, please
consider that daily reporting would result in an additional 58
entries (flow and time) on our MR-1 each month. We cannot see
any merit to increasing our reporting frequency. Accordingly, we
propose to continue to report Discharge 003 for flow on a weekly
basis.
6. Dischar�mit
Our average daily flow limit is 0.181 MGD under our old permit.
You have proposed that it be reduced to 0.076 MGD. Please note
that 0.076 M® is the average of our monthly averages for 1984
_June through 1985 May as reported in our application. As you can
see on Attachment #4, flow for that period was unusually low.
The average of our monthly averages for 1981--1985 is 0.109. We
have exceeded our present limit of 0.181 MGD five (5) times in
the last four (4) years. In almost every occasion, heavy
rainfall of one inch or more over the lagoon caused this flow
excursion.
With a total watershed of approximately 1.75 acres at our lagoon,
one (1) inch of rain in 24 hours will result in an average daily
flow of 0.048 MGD all by itself. This is 63% of the proposed
flow limit! We have no control of this flow.
Also, please note that the present and proposed parameters for
this discharge all have mass limitations - not concentration. We
propose that our daily average flow limit remain unchanged at
0.181 MGD.

APPENDIX 1.4
PAGE 3
COMMENTS ON PROPOSED NPDES PERMIT NO. NC0004308 - EXISTING PARAMETERS
Discharge 004 - Storm Drain and Non --Contact Cooling of Air Compressors
1. Temperature
A. Measurement Frequency
We have been monitoring this discharge monthly under our old
permit. You have proposed that we monitor this discharge weekly.
If you will refer to Attachment #5, you will see that our
discharge temperature closely follows the ambient air temperature
and is very consistent from year-to-year. In our opinion, this
temperature is seasonal and predictable. We can see no merit in
increasing our measurement frequency of this discharge.
Accordingly, we propose to monitor Discharge 004 for temperature
on a monthly basis.
2. Flow
A. Measurement Frequency
We have been monitoring this discharge weekly. You have proposed
that we continue to monitor weekly. Please refer to Attachment
#6, and you will see that it is faily consistent and
predictable. It goes up during the wet season and down during
the dry season. Generally these trends extend over months, not
weeks. We can see no merit in continuing weekly monitoring.
Accordingly, we propose to monitor Discharge 004 for flow on a
monthly basis.
A. Measurement Frequency
We have been monitoring this discharge monthly under our old
permit. You have proposed that we monitor this discharge
weekly. If you will refer to Attachment #7, you will see that
the pH typically ranges between 7.0 and 8.0 and is very
consistent. This discharge is primarily non -contact cooling
water with no water treatment. Accordingly, we propose to
monitor Discharge 004 for pH on a monthly basis.

APPENDIX 1.5
PAGE 4
COn4ENTS ON PROPOSED NPDES PERMIT NO. NC0004308 - EXISTING PARAMETERS
Discharge 005 -- Storm Drain
1. Flow
A. Measurement Frequency
We have been monitoring this discharge weekly under our old
permit. You have proposed that we continue to monitor it
weekly. If you will refer to Attachment #8, you will see that
the flow typically ranges between 0.025 and 0.175 MGD and is very
consistent and predictable. We can see no merit in continuing
weekly monitoring. Accordingly, we propose to monitor Discharge
005 for flow on a monthly basis.
2. pH
A. Measurement Frequency
We have been monitoring this discharge monthly under our old
permit. You have proposed that we monitor weekly. Please refer
to Attachment #9, and you will note that the pH typically ranges
from 7.0 to B.O. Since this is a storm drain, we can see no.
merit in weekly monitoring. Accordingly, we propose to continue
to monitor Discharge 005 for pH on a monthly basis.

APPENDIX 1.6
PAGE 5
COhMENTS ON PROPOSED NPDES PERMIT NO. NC0004308 - EXISTING PARAMETERS
Discharge 006, 007, and 008 - Non Contact Cooling of Generator Housing
Aar -to -Water Heat Exchangerg
1. Temperature
A. Measurement Fr_equem
We have been monitoring this discharge monthly under our old
permit. You have proposed that we monitor it weed. If you
will refer to Attachment #10, 11, 12, you will note that the
discharge temperature closely follows the ambient air temperature
and is very consistent from year-to-year. In our opinion, -this
temperature is seasonal and predictable. Please note that the
combined flow of all three (3) discharges (2.0 MGD) is an
insignificant 1/300 of the river flow (6000 MGD) and that the
temperature rise through these heat exchangers is only
approximately 30C. This would result in a 0.0010C rise in
the Yadkin River's ambient water temperature. Accordingly, we
propose that monitoring Discharges 006, 007, and 008 for
temperature be stopped altogether,
B. Sampling Locations
We have been monitoring this discharge at the effluent only under
our present permit. You have proposed that we monitor our
effluent as well as upstream and downstream. Please note that
access to the top and base of the dams is both time consuming and
dangerous. In all cases, access to the base will require three
separate boat launchings and boat trips of several miles. We
estimate that it would require one person an entire day just to
access the sites of our darns one time and would require us to
purchase a motor boat and a vehicle to tow it. Considering the
source of the discharge, the above information and our comments
in 1.A. above, we can see no merit in this monitoring.
Accordingly, we propose that monitoring Discharge 006, 007 & 008
for temperature be stopped altogether.
2. pH
A. Measurement Fr n
We have"be'en'moiiatoring this discharge monthly under our old
permit. You have proposed that we monitor it weekly. If you
will refer to Attachment #13, 14 & 15, you will see that the pH
ranges between 6.3 and 7.1 and is very'consisten.t and
predictable. We do nothing to these discharges to alter their pH
in any way since the water merely passes through a air--to-rater
heat exchanger. We can see no merit in this monitoring.
Accordingly, we propose that monitoring Discharges 006, 007, and
008 for pH be stopped altogether.

APPENDIX 1.7
PAGE 6
COMMENTS ON PROPOSED NPDES PERMIT NO. NC0004308 - EXISTING PARAMETERS
Discharg_e__ 006, 007, and 008 - Non Contact Cooling of Generator_Housing
Air -to -Water Heat Exc _ er - Continued
3. Flow
A. Measurement Frequency
We have been monitoring this discharge monthly under our old
permit. You have proposed that we monitor it weekly. If you
will refer to Attachments #16, 17, and 18, you will see that this
flow does not change. The reason is quite simple - the system is
pressurized by the lake head. We have a valve in the supply line
that controls the flow rate through the air -to -water heat
exchanger. Our cooling requirements are constant so this valve
does not need periodic adjustments. The reported flow rate gives
us optimum cooling. We can see no merit in this monitoring.
Accordingly we propose that monitoring Discharges 006, 007 and
008 for flow be stopped altogether.

APPENDIX 1_B
PAGE 7
C0Nt=S ON PROPOSED NPDES PERMIT NO. NC0004308 - EXISTING PARAMETERS
Discharge 009 - Storm Drain
1. Te rature
A. Measurement Frequency and Sample Location
We have been monitoring our effluent monthly under our old
permit. You have proposed that we monitor our effluent as well
as upstream and downstream locations weekly. If you will refer
to Attachment #19, you will see that our discharge temperature
closely follows the ambient air temperature and is very
consistent from year-to-year. With a river flow of 6000 MGD and
a discharge flow of 0.5 MGD, a 2.80C rise in the Yadkin River's
ambient water temperature would require a water discharge
temperature of 33,6000C! This is impossible. This water is
not used for any cooling in our plant, and we cannot see any
merit to this monitoring. Accordingly, we propose that
monitoring of Discharge 009 for temperature be stopped
altogether.
2. Flow
A. Measurement Frequency
We have been monitoring this discharge weekly under our old
permit. You have proposed that we continue to monitor it
weekly. If you will refer to Attachment #20, you will see that
our flow has typically ranged between 0.05 and 0.15 MGD and is
very consistent and predictable. We can see no merit in
continuing weekly monitoring. Accordingly, we propose to monitor
Discharge 009 for flow on a monthly basis.
3, .H
A. Measurement Frequency
We have been monitoring this discharge monthly under our old
permit. You have proposed that we monitor this discharge
weekly. If you will refer to Attachment #21, you will see that
our pH has typically ranged from 7.0 to 8.0 for the last three
(3) years. We cannot see any merit to increasing our
monitoring -.-Accordingly, we propose to monitor Discharge 009 for
pH on a monthly basis.

APPENDIX 2
A1LUMNUKGOT 1F'ANY OF AMEBIC A
P.O. sox 6N
DAMN, N011TH CAROLINA 28009
1988 March 10
Department of NRCD
Division of Environmental Management
P. 0. Box 27687
Raleigh, North Carolina 27611
Attention: Mr. M. Dale Overcash
NPDES Permits Group
Gentlemen:
Ref: Renewal of NPDES Permit No. NCO004308
CERTIFIED MAIL
RETURN RECEIPT
Proposed limits for Fluoride and Cyanide from Discharge 009
cannot be met at this time using any available technology. My
letter to you, dated 1987 August 03, indicated.our plans to
performed a Waste Load Allocation Modeling Study on NPDES
Discharge 009 for Fluoride and Cyanide. The study was
performed in late 1987.
The study recommended the the following permit limits:
1. Discharge 009: Cyanide (Free) 2.15 mg/l
Fluoride 774 mg/1
2. Discharge 002: Sulfate 250 mg/l
We propose that the above limits for cyanide and fluoride
for 009 be incorporated in our NPDES Permit.
We,also propose that monitoring for sulfate in 002 be dropped
from our permit in view of our historically low emission rate
and the above recommended limit for -that parameter.
Please review the attached final report from FTN Associates.
If you do not concur with the above recommendations or the
conclusions of this study, please notify me at once.
Very truly yours,
Conrad A. Carter, P.E.
Manager, Environmental Protection
cc: Mr. J. Thurman Horne, DEM, Mooresville (Letter only)
T. W. Baugh/H. E. El 1 is --Alcoa '('i:etter only)
P. R. Atkins/M. E. Kommer-lab, Pgh Office
File:NPOESRAL

En ineer Date Rec.
ANPDES WASTE LOAD ALLOCATION s-7_Facility Name: ` C a a Date '3 � y �8 (p
Existing
Permit No .: lV G o b'b`(3 Og Pipe No .: 0 O County: S Proposed O
o
Design Capacity (MGD): l�3•� o Industrial (% of Flow): Domestic ( of Flow): d
Receiving Stream: Class: Sub -Basin: 03 O 7 O 19
Reference USGS Quad: i D (Please attach) Requestor: L4-sgx Cam + Regional -Office
(Gutdeline ltmitations, it applicable, are to be listed on the back of this form.)
Design Temp..
7Q10 (cfs)
Drainage Area (mil):
Avg. Streamflow (cfs):
Winter 7Q10 (cfs) 30Q2 (cfs)
Location of D.O. minimum (miles below outfall) : Slope (fpm)
Velocity (fps): K, (base e, per day): K2 (base e. oer day):
L-ev
Effluent
Characteristics
Monthly
Average
Comments
w.v,tOQ.
O. ao�
��uprlaG
I,g
Sct1`• .�l�s
O • �
� t
011
•1�-��pop
0 -
Lion V-
ion Q
By: P'L: Reviewed
Effluent
Characteristics
.'.'Dnthly
Lverage
Comments
T
�,sLa.,� -
� t
2'GLIV� wtlL� t}
06Jrd *0
Zug C4iop�C_
6-j- a,. J
w c�,l c
Lt C
-} 1
z� NTV
By ; Date: 3101
N
w

APPENDIX 4
WASTELOAD ALLOCATION AND MIXING GONE STUDY
ALCOA Outfalls 002 and 009
for
Badin Lake
Yadkin River
near
Badin, NC a # S
p ice.
Prepared for:
Aluminum Company of .America
Badin, NC Works
Submitted to:
North Carolina
Department of Natural Resources and Community Development
Prepared by:
FTN Associates, Ltd.
3 Inwood Circle, Suite 220
-. Little Rock, AR 72211
February 1988

APPENDIX 5.1
In general, this definition and these requirements are consistent with EPA
guidelines for mixing zones found in EPA (1983) and EPA (1985). The mixing zone
for Outfall 009 was designed to satisfy these requirements by minimizing its size and
thereby its impact on aquatic biota. No mixing zone is required for Outfall 002
because water quality standards are met within the pipe.
Cyanide, (not fluoride) was used to size the mixing zone because it was
identified as the critical constituent in Section.3.1. Based on the diffusion modeling
results (Section 55.1) and the dye study results (Section 4.0), a mixing zone of a 500
* ft radius is recommended for Outfall 009 (Figure 5.1). This is the smallest area that
will insure cyanide concentrations are less than chronic levels (5 ug/1) at its
boundary under discharge conditions of 0.5 mgd (previously permitted flow) and 2.2
mg/l (maximum observed concentration). The diffusion model results indicated it
would take 59 days to reach a chronic level (5 ug/1) at the 500 ft mixing zone
assuming a discharge rate of 0.5 mgd and of 2.2 mg/1 and 7.2 days at a discharge
rate of 0.1 mgd (maximum observed) and concentration of 2.2 mg/l. According to
EPA (1985), the duration for chronic exposure is four days. Since the time required
to reach chronic levels at the proposed mixing zone is greater than four days,
chronic levels are not predicted to be exceeded. In addition, analysis of the
frequency of calm weather for the period of record (Table 5.6) indicated that the
probability of having four days of calm weather is small. The calms listed in Table
5.6 are for all calms within a month, not consecutive periods. In other words, there
are a total of 4.5 days of calm weather distributed throughout the month of January,
not 4.5 continuous days of calm weather. The probability of having 4.5 days of calm
weather is also small.
It is important to note that the mixing zone was also sized to consider short-
circuiting of the effluent plume through the zone. Because the short-circuiting
would be the norm, constituent concentrations within the mixing zone will be
variable and most of the mixing zone, at any given time, will have concentrations
less than chronic levels.
The proposed mixing zone has a surface are of 7.6 ac which represents
approximately 17'percent of the cove surface area and 0.14 percent of the total lake
surface area. Approximately 855 ft of shoreline or 3.4 percent of the cove shoreline
will be included in the zone. The proposed mixing zone is therefore small compared
to the cove and very small compared to Badin Lake. It should therefore have
.:.n: , _. . .. .._ L._.... A
5-16

APPENDIX 5'- 2
'minimal, if any, impact on aquatic biota. It will also not interfere with fish passage.
' The better aquatic habitat is located in other undeveloped parts of the cove.
The size of the mixing zone was also limited so as not to interfere with the
icy __�•;: C '
�t {" adjacent public use area. According to EPA 1986 the human health criteria for
cyanide is 200 ug/l. Historical data from Outfall 009 indicated this criteria is
exceeded only 15 percent of the time. The critical conditions diffusion modeling
Yrr=a=, and the dye study indicate these concentration would be limited to a small area
around the outfall and therefore no human health problems are anticipated.
Historically, there have been no human health -related problems with the outfall.
According to EPA (1985), to prevent lethal conditions in the mixing zone,
acute toxicity concentrations must be met within a distance of 50 ft from the outfall
(i.e., 10 percent of the distance from the outfall structure to the edge of the mixing
zone. The near field measurements from the dye studies indicated a 100 fold
dilution (i.e., required to meet acute levels (22 ug/1) assuming a maximum observed
input of 2,200 ug/1) is achieved within a 50,ft radius zone under both calm and
windy (i.e., short-circuiting) conditions. No problems with acute toxicity are
therefore expected.
For the above reasons, the proposed 500 ft mixing zone meets all of the States
and EPA requirements for mixing zones.
5.6.3 Effluent Limits
In Section 5.5, the mixing effects from five mechanisms (i.e., diffusion, pool
fluctuations, runoff and precipitation, seiche motion, and wind -generated currents)
were individually quantified on a monthly basis. Since these processes are
independent and were developed as independent processes on a monthly basis, they
need to be summed to determine the available dilution. The dilution ratios for the
proposed 500 ft mixing zone are:
Dilution Mechanism
Pool fluctuations
Direct pree-ipitati6n-
Seiche (wind setup)
Wind -generated currents
Total
Minimum
Average
Maximum
L2
8.1
7.1
0.29
0.52
0.71
0.03
0.06
0.10
430
960
1800
431.52
968.68
1871.81
5-17

APPENDIX 6.1
OBSERVED DYE DILUTION RATIOS
ALCOA Badin Works
Outtall # 009
20 Oct 1987
1545-1600 hrs
(29,3 - 29.5 hrs into injecti&h).,
84 *
a 122
500
• 1040 • 994
�65
—100
17 27 101'
N
� I
75 •
107 •
15,000 •
Figure 4.19. Near -field dye dilution ratios for Outfall 009 on 20 October 1987.
4r23

fr�
p,ytiatt 0
NO DYE •
8370�
1790 • !
2510 • '
2090 • /
627 • /
502 • /
386 •
i
359 •
Pier / • 335
228 • ' M �• "J
• `335
• 193 /
• 39
• 33 /
09 /
OBSERVED DYE DILUTION RATIOS
ALCOA Badin Works
Outiall # 009
20 OCt 1987
1645-1655 hrs
(30.3 - 30.4 hrs into injection)
N
— — — _ Plume limits
0 200 400 s�o
I S I S I
SCALE IN FEET
Figure 4.18. Dye dilution ratios and plume extent on 20 October 1987.

APPENDIX 7
Facility Name Gocl.. �g oo _ Permit #1 NG Doo '� 30 g
CHRONIC TOXICITY TESTING REQUIREMENT (QRTRLY)
The effluent discharge shall at no time exhibit chronic toxicity using test procedures outlined in:
1.) The North Carolina Ccriodaphnia;chronic effluent- bioassay procedure (North Carolina Chronic
Bioassay Procedure - Revised *February 1987) or subsequent versions.
The effluent concentration at which there may be no observable inhibition of reproduction or
significant mortality is �%o (defined as treatment two in the North Carolina procedure
document). The permit holder shall perform quarrerl monitoring using this procedure to establish
compliance with the permit condition., The first test will be performed after thirty days from
issuance of this permit during the months of Mae3 j4ft , Sep,, -Dec_ . Effluent
sampling for this testing shall be performed at the NPD S per nitteA final effluent discharge below
all treatment processes.
All toxicity testing results required as -part of this permit condition will be entered on the Effluent
Discharge Monitoring Form (MR-1) for the month in which it was performed, using the parameter
code TGP3B. Additionally, DEM Form AT- I (original) is to be sent to the following address:
Attention: Technical Services Branch
North Carolina Division of
Environmental Management
P.O. Box 27687
Raleigh, N.C. 27611
Test data shall be complete and accurate and include all supporting chemicallphysical measurements
performed in association with the toxicity tests, as well as all dose/response data. Total residual
chlorine of the effluent toxicity sample -must be measured and reported if chlorine is employed for
disinfection of the waste stream.
Should any test data from this monitoring requirement or tests performed by the North Carolina
Division of Environmental Management indicate potential impacts to the receiving strum, this
permit may be -re -opened and modifiedito-include alternate monitoring requirements or limits.
NOTE: Failure to achieve test conditions as specified in the cited document, such as minimum
control organism survival and appropriate.envi.ronmental controls, shall constitute an invalid test
and will require immediate retesting(within.30 days of irtitial'monitoring event). Failure to submit
suitable test results will constitute:a failure 6Fpermit condition.
7Q10 u i4 cfs
Permited Pow /o! MGD Recommended: by:
rWC%
Basin & Sub-b in . 8 3 -07 - o& ...._.. .
Receiving Stream Rao ► �t e _
County DaIV 6" l
"Chronic Toxicity (Cc phnia) P/F at ?U%, Wdp. j , See Part , Condition
- Sep �e c_

APPENDIX 6.1
NORTH CAROLINA WATER QUALITY STANDARDS DOCUMENTATION:
TOXICITY OF FLUORIDE TO FRESHWATER BIOTA
N.C. Department of Natural Resources and Community Development
Division of Environmental Management
Water Quality Planning Branch
June, 1986
This report has been approved for release let
R. Paul Wilms, Director

APPENDIX 8.2
Data from this review were analyzed using EPA methodology
(Stephan, et al, 1984) to calculate a final acute value (FAV)
based on 48 or 96--hr LC50 values. The FAV is designed to protect
95% of species from acute effects of a .toxicant. Data from the
four most sensitive genera were used (brown and rainbow trout, 27
mg/l F; carp, 75 mg/1 F and goldfish, 93 mg/l F and P ilodina,
158 mg/1) (Table 3). Data for PolYcel_is (48-hr LC of 20 mg/l F)
was not used because tests were made in distilWd water which
would greatly enhance Fs toxicity due to removal of hardness.
Distilled water does not reflect natural conditions and thus,
this test is useful only for comparative purposes. Data from Zang
and Zang (1982), Juhnke and Ludemann (1978) and Chaisemartin
(1985) were not used because test species do not have reproducing
populations in North America.
EPA guidelines (Stephan, et al. 1983) recommend acute data
from eight families of freshwater organisms with reproducing
populations in North America. These families and their available
F data are : 1) family Salmonidae (rainbow and brown trout) , 2)
family in Osteichthyes (catfish and bluegill), 3) family in
phylum Chordata (goldfish), 4) planktonic crustacean (Daphnia),
5) benthic crustacean (no available data), 6) an insect (no
available data), 7) family other than Arthropoda (Philodina
[rotifer}) and 8) another family not represented (no data).
Additional acceptable acute data would be from an amphipod or
crayfish (for # 5, benthic crustacean),.stonefly or mayfly (for #
6, insect) and a midge, mollusc or another insect (for # 8,
another family). Since only five of these. eight families are
represented with acute data, the Final Acute Value (FAV) should
be considered as approximate until these additional data are
available. Also, an acute Daphnia test at low hardness (about 20
mg/1 as CaCO ) should be conducted. EPA guidelines also require
algae data which are readily available in the literature
EPA guidelines also recommend three chronic:acute ratios with
one each from a fish (goldfish for F), an invertebrate (two
Daphnia studies for F) and an acutely sensitive freshwater
species. The later is unavailable for F. Considering the
typical fish populations in the North Carolina mountains and the
acute sensitivity of aquatic life. to fluoride, a chronic study
using rainbow trout (the most acutely sensitive species) would be
most appropriate. Chronic:acute ratios are 0.70 for goldfish and
0.09 for Daphnia. The ratio for rainbow trout would probably lie
between these two extremes since approximate ratios for trout
behavior and histology are 0.11 to 0.68, respectively. A final
chronic:acute ratio would be the average of ratios from trout,
Daphnia and goldfish.
Approximate FAV's of 15.6 mg/1 F with trout or 47.9 mg/1 F
without: trout were calculated (Table 3) . Based on this FAV, the
Criterion Maximum Concentration (Stephan, et al. 1983) would be
6.6 mg/1 F with trout of 23.9 mg/l F without trout. ,The FAV
value (15.6 mg/l F) after inclusion (if warranted) of the missing
acute data would be lowered by an average chronic:acute to

APPENDIX 9
Facility Name A c oa, "" D *z-- Permit # A)C-6o o FOR
CHRONIC TOXICITY TESTING REQUIREMENT (QRTRLY)
The effluent discharge shall at no time exhibit chronic toxicity using test procedures outlined in:
1.) The North Carolina C,:riodgnhnia:chronic effluent bioassay procedure(North Carolina Chronic
Bioassay Procedure - Revised *February 1987) or subsequent versions.
The effluent concentration at which there may be no observable inhibition of reproduction or
significant mortality is 2-3% (defined as treatment two in the North Carolina procedure
document). The permit holder shall perform quarrerj mbnitoring using this procedure to establish
compliance with the permit condition.: Tic first test will be performed after thirty days from
issuance of this permit during the months ofJ" - Ste , le.c— . Effluent
sampling for this testing shall be performed at the NP ES periiiiadd rinal effluent discharge below
all treatment processes.
All toxicity testing results required as part of this permit condition will be entered on the Effluent
Discharge Monitoring Form (MR-1).for the month in which• it was performed, using the parameter
code TGP3B. Additionally, DEM Form AT-1 (original) is to be sent to the following address:
Attention: Technical Services Branch
North Carolina Division of
Environmental Management
P.O. Box 27687
Raleigh, N.C. 27611
Test data shall be complete and accurate and include all supporting chemical/physical measurements
performed in association with the toxicity tests, as well as all dose/response data. Total residual
chlorine of the effluent toxicity sample. 'Must be measured and reported if chlorine is employed for
disinfection of the waste stream.
Should any test data from.this.monitoring requirement or tests -performed by the North Carolina
Division of Environmental Management indicate potential impacts to the receiving stream, this
permit may be re -opened and modified'!to include alternate monitoring requirements or limits.
NOTE: Failure to achieve test conditions as specified in the cited document, such as minimum
control organism.survival and appropriate environmental controls, shall constitute an invalid test
and will require immediate re' testing lithin.30 days of initial�monitoring event). Failure to submit
suitable test results will constitute A failure'of-permit condition
7Q10 N CA
Permited ow . a. Z 3 2— MGD Recommended_ by:
,IWC9b _
Basin.& Sub- asirr �a --o
Receiving Streamisa 14 fe-
County Dat — 7-
**Chronic Toxicity -( odaphnia) P/F at 43 %, /iia/'. See Part S , Condition .
�'Dec-

APPENDIX 10
In general, this definition and these requirements are consistent with EPA
guidelines for mixing zones found in EPA (1983) and EPA (1985). The mixing zone
for Outfall 009 was designed to satisfy these requirements by minimizing its size and
thereby its impact on aquatic biota. No mixing zone is required for Outfall 002
because water quality standards are met within the pipe.
anide, not fluoride was used to size the mixing zone because it was
identified as the critical constituent in Section 3.1. Based on the diffusion modeling
results (Section 5.5.1) and the dye study results (Section 4.0), a mixing zone of a 500
ft radius is recommended for Outfall 009 (Figure 5.1). This is the smallest area that
will insure cyanide concentrations are less than chronic levels (5 ug/1) at its
boundary under discharge conditions of 0.5 mgd (previously permitted flow) and 2.2
mg/1 (maximum observed concentration). The diffusi,* model results indicated it
would take 5.9 days to reach a chronic level (5 ug/1) at the 500 ft mixing zone
assuming a discharge rate of 0.5 mgd and of 2.2 mg/l and 7.2 days at a discharge
rate of 0.1 mgd (maximum observed) and concentration of 2.2 mg/l. According to
EPA (1985), the duration for chronic exposure is four days. Since the time required
to reach chronic levels at the proposed mixing zone is greater than four days,
chronic levels are not predicted to be exceeded. In addition, analysis of the
frequency of calm weather for the period of record (Table 5.6) indicated that the
probability of having four days of calm weather is small. The calms listed in Table
5.6 are for all calms within a month, not consecutive periods. In other words, there
are a total of 4.5 days of calm weather distributed throughout the month of January,
not .4.5 continuous days of calm weather. The probability of having 4.5 days of calm
w'eatber is also small.
It is important to note that the mixing zone was also sized to consider short-
circuiting of the effluent plume through the zone. Because the short-circuiting
would be the norm, constituent concentrations within the mixing zone will be
-
variable and most of the mixing zone, at any given time, will have concentrations
less than chronic levels.
The proposed mixing zone has a surface are of 7.6 ac which represents
approximately 1`TpeFcent of the cove surface area and 0.14 percent of the total lake
=;
surface area. Approximately 855 ft of shoreline or 3.4 percent of the cove shoreline
will be included in the zone. The proposed mixing zone is therefore small compared
to the cove and very small compared to Badin Lake. it should therefore have
5-16

APPENDIX 11
DISCHARGE0SE�RIAL NUMBER
17. (Cont'd.)
FOR AGENCY USE
Influent
Influent
Effluent
a
Parameter and Code
b
b
> 0 O
> o@
o
¢
_ r
'7
a
E
_
?'
ro
U
x .?
x 3l u
E
E
gpwn
¢ow4a
za
to
(1)
(2)
(3)
(4)
(5)
(6)
(7)
(8)
,olor 00080
N/A
bU
40
40
0/30
1
G
'hos horns 00665
NIA
N/A
LT.01
LT.01
LT.01
0/30
1
G
Sulfate 00945
N/A
NIA
6.5
6.5
6.5
0/30
1
G
Woride 00940
NIA
6
9
9
9
0/30
1
G
'alcium 00916
N/A
9
10
10
10
0/30
1
G
Magnesium 00927
N/A
1.6
2
2
2
1 0/30
1
G
Sodium 00929
NIA
52
30
30
30
j 0.30
1
G
rrlerlu i �5 jL/ju iv/ M !v/ n uvo UVO VUU v/ -?U I U
Above analyses are based on one sample and.do not
reflect total range.
18. Plant Controls Check If the fof-
lowing plant controls are available
for this discharge.
Alternate oower source for major `4] APS
pumping facility,
Alarm or emergency procedure for s} ALM
power or equipment failure
COmplete Item 19 If discharge Is
from cooling and/or steam water
generation and water treatment
additives are used.
19. Water Treatment Additives ff the ..•
discharge is treated with anv r,nn- ..
ta.iOner, fnr-:L ,i1e�'. _x;A;-
answer ti �Ing' v
a. NameofMaterial(sl 2}t4af, Nalco 7202 78C
b. Name and address of manu-
facturer
C. quantity (pounds added per
million gallons of water treated).
464
Nalco Chemical Co.
2901 Butterfield Road
Oak Brook, IL
Nalco - 7202 = 1'590-'1bs./Mg
780 - 570-1bs/Mg
8735 -- 650 lbs/Mg
464 - 9 lbs/Mg
8735