NC0085359_Wasteload Allocation_20080129

NPDES DOCVHEHT SCANNING COVER SHEET
NC0085839
Twelve Mile Creek WWTP
NPDES Permit:
Document Type:
Permit Issuance
(,Wasteload
Allocation'
Authorization to Construct (AtC)
Permit Modification
Complete File - Historical
Engineering Alternatives (EAA)
Correspondence
Owner Name Change
Instream Assessment (67b)
Speculative Limits
Environmental Assessment (EA)
Document Date:
January 29, 2008
This document ioa printed on rein a paper - ignore a.ny
content on the i ' rci se Bide

ARD:
ih.ul C. Aughtry, Ili
Chairman
Edwin H. Cooper, III
Vice Chairman
-even G. Kisner
cretary
4
PROMOTE PROTECT PROSPER
C. Earl Hunter, Commissioner
Promoting and protecting the health of the public and the environment
0
January 29, 2008
Mr. James N. Struve, P.E.
Hazen and Sawyer, P.C.
4944 Parkway Plaza Blvd. Suite 375
Charlotte, NC 28217
4
RE: Twelve Mile Creek WWTP, Union County, NC - Wasteload Allocation
BOARD:
Henry C. Scott
M. David Mitchell, MD
Glenn A. McCall
Coleman E Buckhouse, MD
rib NPDES Permit No. SC00Proposed
Lancaster County
4
Dear Mr. Struve:
The Water Quality Modeling Section has reviewed your request asking for a wasteload allocation for
I!t the proposed discharge to Twelve Mile Creek and Catawba River, and determined that a wasteload
allocation for the proposed discharge to Twelve Mile Creek cannot be issued due to the water
011) quality in the receiving water. As a backup plan, a wasteload allocation has been obtained for
Olt Twelve Mile Creek WWTP at the proposed flow of 3, 6, and 9 MGD to Catawba River. This
wasteload information will replace or supersede all previous wasteload information provided based
on new information presented by the Water Quality Modeling Section.
0
4
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0
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4
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044
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Based on the wasteload allocation, the NPDES limits can be expected to be as follows (these are
generally monthly. average values unless noted, additional limits with weekly average and daily
maximum concentrations may also be included):
Parameter
Mass Limits (Ibs/day)
Concentration Limits
(mg/L)
Daily
Maximum
Monthly Average
Weekly
Average
Daily Maximum
Monthly
Average
Weekly
Average
Flow (MGD)
3/6/9
3/6/9
BODS (Mar -Oct)
125/250/375
188/375/563
--
5
7.5
---
BODS (Nov -Feb)
250/500/750
375/751/1126
---
_ 10
15
---
TSS
750/1501/2252
1126/2252/3378
---
30
45
---
NH3-N (Mar -Oct)
25/50/75
38/75/113
---
1
1.5
---
NH3-N (Nov -Feb)
50/100/150
75/150/225
—
2
3
---
TRC
0.28/0.55/0.83
—
_
0.48/0.95/1.43
0.011
---
0.019
Dissolved Oxygen
—
---
---
—
---
6.0(minimum
at all times)
Fecal Coliform
—
---
200/100mL
--
400/100mL
Total Cadmium
0.0085/0.017/0.026
—
0.048/0.095/0.14
0.00034
--
0.0019
Total Copper
0.24/0.49/0.73
--
0.33/0.65/0.98
0.0097
—
0.013
Total Lead
0.08/0.16/0.24
--
2.08/4.15/6.23
0.0032
---
0.083
Total Zinc
MR
---
4.0/8.0/12.0
MR
---
0.16
Total Phosphorus
Monthly Average: 41.7
12 Month Average: 20.85
—
—
---
Total Nitrogen
MR [ MR —
MR
MR
-
WET Chronic
0100%
SOUTH CAROLINA DEPARTMENT OF HEALTH AND ENVIRONMENTAL CONTROL
2600 Ru11 Street • Columbia, SC 29201 • Phone: [phone] • www.scdhecgov
4
ailth

The following conditions should be noted. The wasteload is informational only until the following
actions occur:
1. A determination whether the project is consistent with the applicable 208 Water Quality Plan
must be made on the proposed discharge during the NPDES permit process.
2. In situations where a permittee proposes a new or expanded discharge into surface waters
whose quality is greater than water quality standards (i.e., higher quality waters), an
alternatives analysis shall be included in the engineering report. The report should also
show that the proposal is necessary to important social and economic development in the
area of the receiving waters such that the discharge should be allowed under the anti -
degradation provisions of Regulation 61-68 (Water Quality Standards). The alternatives
analysis shall demonstrate that none of the following applicable alternatives are
economically and technologically reasonable:
(a) Reuse that would minimize or eliminate the need to lower water quality;
(b) Use of other discharge locations;
(c) Connection to other wastewater treatment facilities;
(d) Use of land application;
(e) Product or raw material substitution; and
(f} Any other treatment option or alternative, which would minimize or eliminate the need
to lower water quality.
2. An NPDES permit application and preliminary engineering report is provided on the
proposed discharge. Please note that the NPDES permitting action must be completed in
accordance with Regulation 61-9, and no appeals filed, before a Construction Permit could
be considered for this project.
3. The selected wasteload allocation is subject to EPA Region IV certification since this is a
major facility.
4. Additional metals testing and/or requirements may be necessary subject to information
provided with the NPDES application and/or PER. Submission of available effluent metals
data may result in specific pollutants to be added or deleted from the limits.
5. Please note that the applicant must comply with the provisions of R61-9.600 (Viability
Requirements) that address entities owing wastewater systems have the technical,
managerial and financial means to comply with the regulations as a prerequisite for receiving
a wastewater discharge permit (NPDES). As part of the NPDES process, please provide a
business plan (e.g. audit) or other documents identifying the viability of the facilities.
6. Please note that Twelve Mile Creek WWTP will have a reliability classification of class I,.in
accordance with R.61-67. The WWTP assigned a class I shall meet the requirements listed
in Section 67.400. We would verify Class I wastewater reliability items at the time you
propose the outfall line which will require a SC construction permit (provided an NPDES
permit is issued and not appealed).
If you have any questions, please do not hesitate to call me at [phone].
Michael J. Montebello, Manager
Domestic Wastewater Permitting Section
Water Facilities Permitting Division

•
• jh
O cc: Region 3, Lancaster EQC Office
Beth Quattlebaum, SC DHEC (w/a)
• Mark E. Tye, Perblic Works Department, Union County, NC (w/a)
40 Jeff deBessonet, Director, Water Facilities Permitting Division
Larry Turner, Manager, Water Quality Modeling Section
40 Erica A. Johnson, Water Quality Modeling Section
40 Attachment: Wastaload Allocation Worksheet
40
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Re: Low flow estimates for Sixmile Creek - Lancaster County
Subject: Re: Low flow estimates for Sixmile Creek - Lancaster County
From: "Larry Turner" <[e-mail]>
Date: Mon, 12 Mar 2007 10:53:20 -0400
To: <[e-mail]>
CC: "Sandra Benson" <[e-mail]>
Toya, we've looked over the available USGS info and have found some interesting information. The two partial
record stations I discuss below were not correlated to the 12 Mile Ck station (02146900) to get their generation
coefficients. Rather, they evidently correlated best with stations far away, not even in the same type geographic
areas.
021468701 (Map Reference 78) is the partial record station on 6 Mile Ck with a drainage area of 9.38 sq miles. Six
measurements were taken there between 1981 and 1986: 1.80; 0.67; 1.09; 4.61; 0.50; and, 0.80 cfs. These
measurements were correlated to station 02178400 (Tallulah River near Clayton Ga) to get a 7Q10 of 0.53 cfs and
a generation coefficient of 0.06 cfs/sq mile.
021469901 (Map Reference 79) is the partial record station on 6 Mile Ck with a drainage area of 39.6 sq miles.
Ten measurements were taken there between 1981 and 1986: 2.91; 7.48; 1.82; 11.5; 0.21; 4.27; 5.52; 2.58;
4.60; and, 0.93 cfs. These measurements were correlated to station 02149000 (Cove Ck. near Lake Lure) to get a
7Q10 of 1.3 cfs but the generation coefficient was only listed as <.1 cfs/sq mile.
I have only a limited understanding of the USGS statistical procedures for determining an appropriate continuous
record station with which to correlate partial record data. It appears these stations were better fits with the partial
record data than the nearby continuous record station meaning there is some differences between the 6 Mile and
12 Mile watersheds...that, or the thunderstorms missed one or the other during the sampling! Due to the long
period of record of the continuous record station in the watershed, I'd be very tempted to apply that generation to
the whole watershed rather than use the partial record stations for the incremental area. No matter how you cut
it, the 7Q10 at the Catawba will be on the order of 2 or less. Please let me know what you decide to do...we are
updating some flows on the Catawba and would like to be consistent with your numbers for our Catawba model
input. We need to decide this quickly, my modeler who is trying to finish this is leaving in a week or so. If you
would like to discuss, please call me at 803.898.4005. Thanks, LT
»> Toya Fields <[e-mail]> 3/9/2007 10:02 AM »>
Hi Larry,
Sorry for the delay, I just sent the information that I have for 12 Mile
Creek. I thought about using the same generation coefficient for 6 Mile
Creek as we have for 12 Mile creek, unless someone has additional
information, so we may just have to do that. Let me know if you have
any more thoughts.
Toya
Larry Turner wrote:
> Toya, 'sorry but I missed the second part of your message yesterday.
> USGS Report 90-4188 is one of the sources we use to estimate 7Q10 when
> we don't have site specific data...which is frequently. We would do a
> standard extrapolation using the generation coefficient from one of
> the partial record stations and the drainage area at the point of
> interest. Interestingly, USGS published a unit 7Q10 of 0.06 cfs/mi2
> at the upstream station (Site 78, 021468701) but only said the
> generation coefficient was "<.1" at the downstream station (Site 79
> 021469901)...though they gave a 7Q10 value at the site of 1.3 cfs. If
> we had no other data, we'd probably divide the 1.3 by the area of 39.6
1 of 4 3/20/2007 1:32 PM
' i

Re: Low flow estimates for Sixmile Creek - Lancaster County
> square miles and use a generation coefficient of 0.03 and apply it to
> the area at the junction of 12 Mile Ck and the Catawba to estimate a
> flow. If the station on 12 Mile Ck above the discharge is a
> continuous record station with a decent period of record, I'd consider
> going with the generation coefficient there to apply to the whole
> watershed...unless there is some evidence the 6 & 12 Mile Ck
> watersheds are not hydrologically similar. When in doubt, we're
> usually conservative!
> Were you able to come up with the USGS "report" for the station above
> the Union Co. discharge? I'd be interested in seeing how it compared
> to the partial record stations. You can fax it to me at 803.898.4140
> if you were able to find it. Union County's consultant has sent me
> some water quality and flow info...I believe what he had previously
> sent you. 'Looks like during the "2002 drought" the flows were low as
> were the DOs. Thanks for keeping me in the loop on this one. It will
> be interesting to see how you approach this one. LT
> **************************************************************
> Toya, thanks for the info. If you could fax me the USGS "report". My
> guess would be that we would have to extrapolate downstream flow using
> the generation coefficient from the station just upstream of the
> discharge but we'll check and see if anything else is available. My
> fax number is:
> Thanks, LT
> Larry Turner
> SCDHEC, Water Quality Modeling
> 803.898.4005
> [e-mail] <mailto:[e-mail]>
> »> Toya Fields <[e-mail]> 3/7/2007 11:52 AM »>
> Thanks Larry,
> Our USGS contact forwarded the following. Also, I can fax you a report
> they developed in 2002 (one page) for 12 Mile Creek up at the Union
> County discharge. It was based on a record station that is about 2500
> feet above the outfall. Right now I don't have data for 12 Mile Creek
> at the Catawba, but I did contact our modeling folks and they might have
> something. I'll let you know if I get anything else.
> Toya
> We have two partial -record stations on Six Mile Creek for which low -flow
> statistics were computed in the mid 1980s. Unfortunately, the USGS has
> been unable to secure cooperator funding to update low -flow statistics
> for South Carolina streams in recent years. Listed below is the
> information we have available for Six Mile Creek. This information comes
> from the following USGS report:
> Zalants, M.G., Low -flow characteristics of natural streams in the Blue
> Ridge, Piedmont, and upper Coastal Plain physiographic provinces of
> South Carolina: U.S. Geological Survey Water -Resources Investigations
2 of 4 3/20/2007 1:32 PM

Re: Low flow estimates for Sixmile Creek - Lancaster County
> Report 90-4188.
> The report is available on-line at the following address:
> http://pubs.er.usgs.gov/usgspubs/wri/wri904188
> Larry Turner wrote:
> > Ms. Fields, I'II check and see what we have. I am not aware of any
> > dischargers we have in the area but we may have done some relevant
> > work. We'II also check for any USGS partial record stations in the
> > area. I would be interested in your low flow estimates for 12 Mile Ck
> > and how they were determined...what USGS stations you have, etc.
> > We'II try to get back with you in the next couple of days. Thanks, LT
> > Larry Turner
> > SCDHEC, Water Quality Modeling
> > 803.898.4005
> > [e-mail] <mailto:[e-mail]>
> > »> Michael Montebello 3/7/2007 7:51 AM »>
> > Ms. Fields,
> > We met with Union County folks and their engineer recently about the
> > proposed expansion and Mr. Larry Turner (Manager, Wasteload Allocation
> > Section) would be the best for this question. I have forwarded your
> > request to him and copied him on this email..
> > Thanks
> > Mike Montebello
> > Michael Montebello, Manager
> > Domestic Wastewater Permitting Section
> > Phone [phone]
> > Fax [phone]
> > [e-mail] <mailto:[e-mail]>_
> > »> Toya Fields <_ [e-mail]
> ><mailto:[e-mail]>_ > 03/06/07 4:11 PM »>
> > Hi Mike,
> > We've gotten a request for speculative effluent limits from Union County
> > for their Twelve Mile Creek WWTP. I have low flow estimates for
> > Twelvemile Creek up at the discharge point, but I'd like to extend the
> > model down to its confluence with the Catawba. Sixmile Creek is the
> > largest tributary and we don't have any flow estimates for that stream
> > in South Carolina. Would you happen to have streamflows for Sixmile
> > Creek at its confluence with Twelvemile creek? What about Twelvemile
> > Creek at the Catawba River? Anything you have would be appreciated.
> > Thanks for your help,
> > Toya Fields
>> --
> > Toya Fields - [e-mail] <mailto:[e-mail]>_
3 of 4 3/20/2007 1:32 PM

MODEL INPUTS FOR LEVEL B ANALYSIS
GENERAL INFORMATION
Facility Name: -Ti,ji/ Vf in/Lc (
F[ k. (r .Tl
NPDES No.: NCOO 2c-C3,0
Type of Waste: /aj% Thyonni c
-1
Facility Status: .)(-15 I //vel
Receiving Stream: 1---tjcL ✓C
'it (gat
Stream Classification:
Subbasin: 0,_1- O 7 —3 F
County:
Regional Office:
Topo Quad:
FLOW INFORMATION
uscS # Col 1410 9 00 -7 t,i
v{ i ri (L F
CI ,1Ji:, 2 i
1-4X Fllgr..J
Date of Flow Estimates://S7o,7
Drainage Area (mi2): 7 6.S
Summer 7Q10 (cfs): O. /
&611,(17/..a.,-41Winter
7Q10 (cfs): /.c.
4-en,p i3.d.
oC
Average Flow (cfs): -/a, 7
•LOt , 3, 14S
30Q2 (cfs): 3. e?
IWC at Point of Discharge (%):
Cummulative 1WC (%):
���fJ�yy� :.�.a /�.f' �vo• ::$-t: ;:\`5..,� t}{t:}2:^, .:;:;;Y'o:o:o.,:i.::r s.:::s•;;. Y::�i<' . �C'. :/f-...0 :. !CC. ii0Y5'�... Tv.>iy' try.6x Jt}r,.:.i r". c.Clr�fny}Sf> gyy���vih3. ://•. �iS if25::i�i:
An JN0 Fn sG`U'. ay.�. \( lh\.; C<KL(R^ !:ZYY"" 4 T��+lb1>riJ�tt4(QSJ !)�/xt{N., j fir.
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MODEL INPUT INFORMATION 1
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LENGTH OF REACH (miles)
,:-). 5
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4. 6.
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INCREMENTAL LENGTH (miles)
0. 1
0, I
0, 1
0,
WASTE CHARACTERISTICS
FLOW (MGD)
CBOD (mg/1) L m/ s
NBOD (mg/1) V i4 5-
D.O. (mg/1)
RUNOFF Q-IARACTERISTICS
7Q10 (cfs/mil)
QA (cfs/mil)
CBOD (mg/1)
NBOD (mg/1)
D.O. (mg/l)
TRIBUTARY CHARACTERISTICS
7Q10 (cfs)
DOS
QA (cfs)
3 7, 64
CBOD (mg/I)
NBOD (mg/1)
D.O. (rng/l)
SLOPE (fpm)
, 3s-
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Name of facility

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Program
Station #
Location
Latitude
Longitude
Result Date/Time
Depth (m)
ethod Coc
Method Name
Result
Remark
Comment
NCAMBNT
NCAMBNT
NCAMBNT
NCAMBNT
NCAMBNT
NCAMBNT
NCAMBNT
NCAMBNT
NCAMBNT
NCAMBNT
NCAMBNT
NCAMBNT
NCAMBNT
NCAMBNT
NCAMBNT
NCAMBNT
NCAMBNT
NCAMBNT
NCAMBNT
NCAMBNT
NCAMBNT
NCAMBNT
NCAMBNT
NCAMBNT
C9819500
C9819500
C9819500
C9819500
C9819500
C9819500
C9819500
C9819500
C9819500
C9819500
C9819500
C9819500
C9819500
C9819500
C9819500
C9819500
C9819500
C9819500
C9819500
C9819500
C9819500
C9819500
C9819500
C9819500
NC 16 NR WAXHAW
NC 16 NR WAXHAW
NC 16 NR WAXHAW
NC 16 NR WAXHAW
NC 16 NR WAXHAW
NC 16 NR WAXHAW
NC 16 NR WAXHAW
NC 16 NR WAXHAW
NC 16 NR WAXHAW
NC 16 NR WAXHAW
NC 16 NR WAXHAW
NC 16 NR WAXHAW
NC 16 NR WAXHAW
NC 16 NR WAXHAW
NC 16 NR WAXHAW
NC 16 NR WAXHAW
NC 16 NR WAXHAW
NC 16 NR WAXHAW
NC 16 NR WAXHAW
NC 16 NR WAXHAW
NC 16 NR WAXHAW
NC 16 NR WAXHAW
NC 16 NR WAXHAW
NC 16 NR WAXHAW
34.95225
34.95225
34.95225
34.95225
34.95225
34.95225
34.95225
34.95225
34.95225.
34.95225
34.95225
34.95225
34.95225
34.95225
34.95225
34.95225
34.95225
34.95225
34.95225
34.95225
34.95225
34.95225
34.95225
34.95225
-80.75581
-80.75581
-80.75581
-80.75581
-80.75581
-80.75581
- 80.75581
-80.75581
-80.75581
-80.75581
-80.75581
-80.75581
-80.75581
-80.75581
-80.75581
-80.75581
-80.75581
-80.75581
-80.75581
-80.75581
-80.75581
- 80.75581
- 80.75581
- 80.75581
2005-01-25 11:nn
2005-02-21 15:nn
2005-03-21 13:nn
2005-04-21 10:nn
2005-05-19 13:nn
2005-06-27 12:nn
2005-07-26 12:nn
2005-08-30 12:nn
2005-09-19 14:nn
2005-10-17 13:nn
2005-11-14 11:nn
2005-12-13 12:nn
2006-01-25 11:nn
2006-02-21 14:nn
2006-03-15 13:nn
2006-04-20 14:nn
2006-05-18 12:nn
2006-06-15 15:nn
2006-07-19 13:nn
2006-08-23 15:nn
2006-09-21 13:nn
2006-10-16 12:nn
2006-11-15 13:nn
2006-12-12 10:nn
0.1 300 (mg/L)
0.1_....._.._ 300 (mg/L)
0.1 300 (mg/L)
0.1 300 (mg/L)
0.1 300 (mg/L)
0.1 300 (mg/L)
0.1 300 (mg/L)
0.1 300 (mg/L)
0.1 300 (mg/L)
0.1 300 (mg/L)
0.1 300 (mg/L)
0.1 300 (mg/L)
0.1 300 (mg/L)
0.1 300 (mg/L)
0.1 300 (mg/L)
0.1 300 (mg/L)
0.1 300 (mg/L)
0.1�300 (mg/L)
0.1L 300 (mg/L)
0.1 300 (mg/L)
0.1 300 (mg/L)
0.1 300 (mg/L)
0.1 300 (mg/L)
0.1 300 (mg/L)
13
9.9.
11
8.6
7.8
7
5.7
7
6.4
7.6
5.7
11.2
10.4
14.4
11.6
7.7
8.1
7.1
5.7
5
7.5
8.8
8.5
11.3
1
gat- /61 &Jar dgot- 0/00c,
Pa 3Q121L
020. r0z
gYltileloo
USeo S d(y

Twelvemile Creek Dissolved Oxygen Summary
Twelve Mile Creek Stream Data
Upstream Location
50 FT ABOVE OUTFALL
Twelve Mile Creek Stream Data
Downstream I Location
1/4 MILE BELOW OUTFALL
Twelve Mile Creek Stream Data
Downstream II Location
BRIDGE AT SR 1301
# violations DO standard from Jan 05-Dec 06
30
t violations of DO standard from Jan 05-Dec 06
39
t violations of DO standard from Jan 05-Dec 06
34
% violations
17%
% violations
22%
% violations
20%
Data set analysis (2001-2006)
Data set analysis (2001-2006)
Data set analysis (2001-2006)
95th perccentile
12.288
95th perccentile
11.786
95th perccentile
12.088
75th percentile
8.215
75th percentile
7.855
75th percentile
8.21
median
6.4
median
6.27
median
6.46
25th percentile
4.74
25th percentile
5.165
25th percentile
5.51
5th percentile
2.553
5th percentile
3.993
5th percentile
4.421
6(6/tA, 7

Dissolved Oxygen (mg/L)
16.00
14.00
12.00
WWTP Discharge Characteristics vs Instream gta Dep.
C L vuS T 26191-
10.00
8.00 -
6.00 -
4.00
2.00
0.00
I
f
Me_ pi-4.
5.
4.
3.
2.
1
o.
Jan-01 Jul-01 Jan-02 Jul-02 Jan-03 Jul-03 Jan-04 JuI-04 Jan-05 Jul-05 Jan-06 Jul-06 Jan-07
Date
Downstream DO Effluent DO WWTP Flow Poly. (WWTP Flow)
Discharge (mgd)

Dissolved Oxygen (mg/L)
16
14
12
10
8
6
2
0
Upstream Dissolved Oxygen Comparison
(Ambient station at NC 16 versus Union County station 50 feet above outfall)
Jan-01 Jul-01 Jan-02 Jul-02 Jan-03 JuI-03 Jan-04
Date
JuI-04 Jan-05
DWQ Ambient Station —Union Co. Upstream Sampling
JuI-05 Jan-06 Jul-06

6.00
5.00
E 4.00
O
ci
3.00
2.00
1.00
Magnification of Low Dissolved Oxygen Values - Downstream I
(1/4 mile below outfall)
39 violations of the 5.0 mg/L
D.O. standard from Jan 05 -
Dec 06 (22% of total)
Jan-01 JuI-01 Jan-02 Jul-02 Jan-03 JuI-03 Jan-04 Jul-04 Jan-05 Jul-05 Jan-06 Jul-06
Downstream I
Date
D.O. = 5 mg/L D.O. = 6 mg/L

6.00
5.00
E 4.00
O
d
3.00
2.00
Magnification of Low Dissolved Oxygen Values - Upstream
(50 feet above outfall)
I()
k
30 violations of the 5.0 mg/L
D.O. standard from Jan 05 -
Dec 06 (17% of total)
1.00-
Jan-01 Jul-01 Jan-02 Jul-02 Jan-03 Jul-03 Jan-04 Jul-04 Jan-05 Jul-05 Jan-06 Jul-06
Date
Upstream D.O.
D.O. = 5 mg/L D.O. = 6 mg/L

6.00
5.00
E 4.00
O
3.00
2.00
1.00
Magnification of Low Dissolved Oxygen Values - Downstream I1
(1/2 mile below outfall)
U
i
1�
34 violations of the 5.0 mg/L
D.O. standard from Jan 05 -
Dec 06 (20% of total)
Jan-01 Jul-01 Jan-02 Jul-02 Jan-03 Jul-03 Jan-04 Jul-04 Jan-05 Jul-05 Jan-06 Jul-06
Date
Downstream II
D.O. = 5 mg/L D.O. = 6 mg/L

6.00 -
5.00
J
E 4.00
O
0
3.00
2.00
1.00
Magnification of Low Dissolved Oxygen Values - Upstream
(50 feet above outfall)
•
1
J
30 violations of the 5.0 mg/L
D.O. standard from Jan 05 -
Dec 06 (17% of total)
•
30.0
25.0
- 20.0
Jan-01 JuI-01 Jan-02 Jul-02 Jan-03 JuI-03 Jan-04 Jul-04 Jan-05 Jul-05 Jan-06 Jul-06
Date
Upstream D.O. D.O. = 5 mg/L D.O. = 6 mg/L - Temperature
5.0
0.0

6.00
5.00
3.00
2.00
1.00
Magnification of Low Dissolved Oxygen Values - Downstream
(1/4 mile below outfall)
i
r
- 30.0
- 25.0
- 20.0
- 15.0
— 10.0
39 violations of the 5.0 mg/L
D.O. standard from Jan 05 -
Dec 06 (22% of total)
Jan-01 Jul-01 Jan-02 JuI-02 Jan-03 Jul-03 Jan-04 Jul-04 Jan-05 Jul-05 Jan-06 Jul-06
Date
Downstream I D.O. = 5 mg/L D.O. = 6 mg/L Temperature
5.0
0.0

6.00
5.00
E 4.00
3.00
2.00
1.00
Magnification of Low Dissolved Oxygen Values - Downstream II
(1/2 mile below outfall)
34 violations of the 5.0 mg/L
D.O. standard from Jan 05 -
Dec 06 (20% of total)
Jan-01 Jul-01 Jan-02 JuI-02 Jan-03 Jul-03 Jan-04 Jul-04 Jan-05 Jul-05 Jan-06 Jul-06
Date
Downstream II D.O. = 5 mg/L
D.O. = 6 mg/L Temperature
— 30.0
— 25.0
— 20.0
— 15.0
- 10.0
— 5.0
0.0

:12:42pm From-USGS
9195714041 T-217 P.002/003 F-553
201
United States Department of the Interior
U.S. GEOLOGICAL SURVEY
3916 Sunset Ridge Road
Raleigh, North Carolina 27607
July 15, 2002
Mr. W.S. Riddick, Jr., PE, Senior Project Manager
McKim & Creed Engineers
2300 Sardis Road North, Suite A
Charlotte, North Carolina 28277
Dear Mr. Riddick:
In response to your request for low -flow data, the U.S. Geological Survey (USGS) provides the following
low -flow characteristics for the continuous -record paging station at Twelve Mile Creek near Waxhaw, NC
(station id 02146900, drainage area 76.5 mi2). The low-tlow data that are provided on the attached sheet
have been computed based on techniques used by the USGS for assessing the low -flow characteristics at
continuous -record gaging stations having 10 or more years of record. Please note that the flow estimates
only account for the effects of any upstream diversions or regulation that have occurred during the period
of record at the gaging station.
The gaging station on Twelve Mile Creek has been in operation since October 1960. The available full
period of record through the most recent water year of published data (2001) was used in the analyses, The
7-day, 10-year (7Q10) low -flow discharge based on this period is 0.10 ft3/s, or 0.0013 ft3/s/mi2 of drainage
area (termed as the 7Q10 yield). A 7Q10 yield of this magnitude indicates fairly low potentials for sustained
base flows relative to other areas in parts of North Carolina. The basin upstream of the gaging station is
underlain by the geologic units of the Carolina Slate 13elt, which has historically been correlated with rela-
tively low potentials for sustained bases flows at many streams within this belt. The 30-day, 2-year (30Q2)
low -flow discharge based on this period is 3.2 ft3/s. or a 30Q2 yield of 0.0412 ft3/s/mi2.
You identified the actual location of the discharge point as being approximately 2,500 feet downstream of
the gaging station. An examination of the topographical quad map showing the location of the gaging sta-
tion and the downstream reach indicates that no tributaries enterinto T\ve ve Mile Creek between the station
and the discharge point. Thus, the low -flow characteristics at the gaging station can be considered applica-
ble to the discharge point.
A charge for accessing and processing information has been assessed to partially offset these costs. Your
requested data and an invoice covering processing costs for these data are enclosed. Please forward the
original bill with your check to the U.S. Geological Survey, 12201 Sunrise Valley Drive, MS 271, Reston,
Virginia 20192_
These data are preliminary and subject to revision pending approval for publication by the Director of the
U.S. Geological Survey, and are made available through our cooperative program of water -resources inves-
tigations with the North Carolina Department of Environment and Natural Resources.
If you have any questions regarding this information, please contact us at [phone].
Enclosures
Sincerely,
J. Curtis Weaver
Hydrologist
WFo1,,-�
[phone] • FAX [phone]

2 42pm From-USGS / 0195714041 T-217 P.003/003 F-553
SUMMARY OF LO*.FLOW EST ATES IN RESPONSEE TORE„ T1EST
_Conti loeS-record (0
AVERAGE W: EatI uated using 0.95
ANNUAL 7Q10 MI] TI1ViUM FLO : 0.0013
ANNUAL 30Q2 MINIM* rt 0.0412
WINTER 7Q10 FL W 0.0200
ANNUAL 7Q2 MU I+"LOW' 0.01.83
(A] Estimate is based on records collected at or near the request site.
Estimate is based entirely on runoff characte• ristics observed at nearby streams.
(C] Estimate basedon procedures given in USGS Water Supply Paper 2403 "Low -flow Characteristics
eanis in North Carol na" (txie aid Mason,1993).
stima�te based on procedures given in CTSGS WSupply Paper 2403 and in co
$trearaflow irecards collected at or near the re,NV,
uest site:
See remarks.
•t`a are considered provisiona
ow - flow. estimates based o•n discharge records coll•ecte•d at gaging station during_ 1961--2000 climatic yes
(12-month period from Aprll 1 through Maxch 31` and designated by the year in which the period begins,
used xi,law-flaw analyses at continuous record gug ng stations)
egi.ested by Mr. Sid Riddick McKim & Creed;Engineers '
FEE CRARGED•

Twelve Mile Creek Stream Data
Upstream Location
50 FT ABOVE OUTFALL
RECENT DATA ANALYSIS
# violations DO standard from Jan 05-Dec 06
% violations
ENTIRE DATA SET ANALYSIS
95th perccentile
75th percentile
median
25th percentile
5th percentile
Twelvemile Creek Dissolved Oxygen Summary
Twelve Mile Creek Stream Data
Downstream I Location
1/4 MILE BELOW OUTFALL
RECENT DATA ANALYSIS
30 violations of DO standard from Jan 05-Dec 06
17% % violations
12.288
8.215
6.4
4.74
2.553
ENTIRE DATA SET ANALYSIS
95th perccentile
75th percentile
median
25th percentile
5th percentile
39
22%
11.786
7.855
6.27
5.165
3.993
Twelve Mile Creek Stream Data
Downstream II Location
•
BRIDGE AT SR 1301
RECENT DATA ANALYSIS
violations of DO standard from Jan 05-Dec 06
% violations
ENTIRE DATA SET ANALYSIS
95th perccentile
75th percentile
median
25th percentile
5th percentile
34
20%
12.088
8.21
6.46
5.51
4.421

16
14
12
J
E 10
c
0
a)
> 6
x
0
0
uu • 6
u)
O
0
Upstream Dissolved Oxygen Comparison
(Ambient station at NC 16 versus Union County station 50 feet above outfall)
Jan-01
Jul-01
Jan-02
Jul-02
Jan-03
Jul-03
Jan-04
Date
JuI-04
Jan-05
Jul-05
DWQ Ambient Station — Union Co. Upstream Sampling —5.0 mg/L
Jan-06
JuI-06

6.00 -
5.00
J
E 4.00
d
0
3.00
2.00
Magnification of Low Dissolved Oxygen Values - Upstream
(50 feet above outfall)
.1
11,
I(
I
30 violations of the 5.0 mg/L
D.O. standard from Jan 05 -
Dec 06 (17% of total)
1.00
Jan-01 Jul-01 Jan-02 Jul-02 Jan-03 Jul-03 Jan-04 Jul-04 Jan-05 Jul-05 Jan-06 Jul-06
Date
r Upstream D.O. D.O. = 5 mg/L D.O. = 6 mg/L

6.00
5.00
J
E 4.00
ci
0
3.00
2.00
1.00
Magnification of Low Dissolved Oxygen Values - Downstream I
(1/4 mile below outfall)
1
M '
I I'
i
I
39 violations of the 5.0 mg/L
D.O. standard from Jan 05 -
Dec 06 (22% of total)
Jan-01 Jul-01 Jan-02 Jul-02 Jan-03 Jul-03 Jan-04 Jul-04 Jan-05 Jul-05 Jan-06 Jul-06
Date
Downstream I
D.O. = 5 mg/L D.O. = 6 mg/L

6.00
5.00
J
E 4.00
O
6
3.00
2.00
1.00
Magnification of Low Dissolved Oxygen Values - Downstream II
(1/2 mile below outfall)
044
u
I
o
4
II
I
1
1
34 violations of the 5.0 mg/L
D.O. standard from Jan 05 -
Dec 06 (20% of total)
Jan-01 Jul-01 Jan-02 Jul-02 Jan-03 Jul-03 Jan-04 Jul-04 Jan-05 Jul-05 Jan-06 Jul-06
Date
Downstream II
D.O. = 5 mg/L D.O. = 6 mg/L

Dissolved Oxygen (mg/L)
16.00
14.00
WWTP Discharge Characteristics vs Downstream DO
12.00 Vi
10.00
8.00
6.00
4.00
2.00
0.00
In
V
6.
5.
4.
2.
0.
Jan-01 Jul-01 Jan-02 Jul-02 Jan-03 Jul-03 Jan-04 JuI-04 Jan-05 JuI-05 Jan-06 Jul-06 Jan-07
Date
Downstream DO Effluent DO WWTP Flow Poly. (WWTP Flow)

Union County, NC - Twelve Mile Creek WWTP Expansion Beyond ...
Subject: Union County, NC - Twelve Mile Creek WWTP Expansion Beyond 6 MGD - Meeting with
SC DHEC
From: "Struve, James N." <j struve @ hazenandsawyer.com>
Date: Wed, 7 Mar 2007 19:08:34 -0500
To: <[e-mail]>
CC: <[e-mail]>, <[e-mail]>, <[e-mail]>, "Larry Turner"
<[e-mail]>, <[e-mail]>, <[e-mail]>, "Berndt, Robert
A." <rberndt @ hazenandsawyer.com>, "Parker, Michael D." <mparker @ hazenandsawyer.com>,
"Taylor, Ronald L." <[e-mail]>, "Rohrbacher, Joe"
<johrbacher @ hazenandsawyer.com>
Good afternoon Susan.
This past Friday (March 2nd), Union County and Hazen and Sawyer met with Mike Montebello, Weijia Hu and
Larry Turner of SC DHEC. The purpose of the meeting was to discuss the expansion of the County's plant
beyond 6 mgd and to address any preliminary concerns/issues SC DHEC may have.
As you are aware, SC DHEC is in the process of calibrating their WARMF model which will assist them in
allocating waste loadings to existing and future NC/SC POTWs discharging into the Catawba River System. In
particular, SC DHEC is primarily concerned with Total Phosphorus (TP). Speculation is that the existing
established TP TMDLs will remain unchanged in order to meet the current SC TP lake standard of 0.06 mg/L.
Based upon an existing established TMDL of 20.85 Ibs/day at the Twelve Mile Creek WWTP, this will result in the
following effective TP concentrations for the various expansion scenarios:
Plant Rated Capacity, mgd
2.5
6.0
9.0
12.0
15.0
Effective TP Concentration, mg/L
1.00
0.42
0.28
0.21
0.17
Mike Montebello indicated that more than likely, SC DHEC will allocate a TP TMDL to NC. In turn, it will be NC's
responsibility to allocate this maximum daily limit to the specific NC POTWs discharging into the Catawba River
System. How this allocation is distributed to the NC POTWs is solely up to NC DWQ. If there is a reallocation of
TP by DWQ, then Union County would certainly expect to be equitably included.
When nitrogen limits was brought up for discussion, SC DHEC indicated that the implementation of Total Nitrogen
(TN) limits is not in the foreseeable future. Again, the biggest driver in SC is TP. In order for POTWs to meet the
TP TMDL, the final effluent must be devoid of solids, and as a result, conventional pollutants such as BOD and
TSS become less of a concern.
Specific water quality concerns with respect to 12 Mile Creek were also discussed. Currently, 12 Mile Creek is not
listed in the 303(d) impaired waters list for NC. Hazen and Sawyer recently compiled and sent NC DWQ stream
flow, temperature and dissolved oxygen (DO) data upstream and downstream of the Plant's discharge into 12
Mile Creek for the years 2001 to 2006. Hazen and Sawyer will also send this same data set to SC DHEC.
However, SC DHEC indicated that at his point and time, they are only concern with copper and turbidity levels
within 12 Mile Creek.
In summary, SC DHEC has no objections to the expansion of the County's Twelve Mile Creek WWTP. However,
Mike Montebello did request the following:
1. To be copied/notified of the speculative limits for the 9, 12, and 15 mgd flow scenarios upon issuance
by NC DWQ.
2. That the County performs a "Confirmatory WER" for copper and zinc following the 9 mgd expansion
if the process changes from completely stirred tank reactor (oxidation ditch) to plug flow (diffused air).
3. Any information from USGS that indicates/supports that the 7Q10 flow for the 12-Mile Creek is
greater than 0 cfs.
1 of 2 3/20/2007 13 PM

Union County, NC - Twelve Mile Creek WWTP Expansion Beyond ...
Please call or email me should you have any questions. We look forward to the receipt of the speculative limits
for 9, 12, and 15 mgd flow scenarios.
Regards,
Jim
James N. Struve, P.E.
Senior Associate
Hazen and Sawyer, P.C.
4944 Parkway Plaza Boulevard, Suite 375
Charlotte, NC 28217
Office [phone]
Cell [phone]
Direct [phone]
Fax [phone]
Email [e-mail]
2 of 2 3/20/2007 1:33 PM

2006 SC List of Impaired Waters by 12-Digit HUC
TA +
DDLT fiMDL ARGET
E(S2013
NOTE
BASIN
HUC
LOCATION
STATION
COUNTY
USE
CAUSE
BROAD
030501080101
BUCKHORN CRK. AT SR 562
B-795
GREENVILLE
AL
BIO
2013
BROAD
030501080101
BEAVERDAM CRK. AT SC 253
B-796
GREENVILLE
AL
BIO
2013
BROAD
030501080101
ENOREE R. AT PINE LOG FORD RD., 2ND CROSSING ABOVE SC 253 BRIDGE
B-797
GREENVILLE
AL
BIO
2012
BROAD
030501080101
ENOREE RVR AT UNNUM RD W US 25 N TRAVELERS REST
BE-001
GREENVILLE
AL
ZN
2013
BROAD
030501080101
MOUNTAIN CRK. AT SR 279
BE-008
GREENVILLE
AL
BIO
2012
BROAD
030501080101
BEAVERDAM CK AT RD 1967
BE-039
GREENVILLE
AL
PH
2013
BROAD
030501080102
PRINCESS CREEK AT SUBER MILL RD, SECOND RD S OF US 29 OFF S-23-540
B-192
GREENVILLE
AL
BIO
2013
BROAD
030501080102
ROCKY CK AT BRDG IN BATESVILLE 1 MI AB JCT WITH ENOREE
BE-007
GREENVILLE
AL
BIO
2013
BROAD
030501080102
BRUSHY CKATS-23-164
BE-009
GREENVILLE
AL
BIO
2013
BROAD
030501080102
BRUSHY CK AT HOWELL RD (S-23-273/335) APPROX 5 MI NE OF GREENVILLE
(B10 B-798)
BE-035
GREENVILLE
AL
BIO
2013
BROAD
030501080103
HORSE PEN CRK. AT SR 145
B-793
GREENVILLE
AL
BIO
2013
BROAD
030501080103
GILDER CK AT S-23-143 1/4 MI AB JCT WITH ENOREE RVR
BE-020
GREENVILLE
AL
BIO
2013
BROAD
030501080104
ENOREE RVR AT SC 296, 7.5 MI NE OF MAULDIN
BE-017
GREENVILLE
AL
BIO
2010
BROAD
030501080105
DURBIN CREEK AT SC 418
B-097
LAURENS
AL
PH
2008
*
BROAD
030501080106
ENOREE RVR AT S-30-112
B-040
LAURENS
REC
FC
2013
BROAD
030501080106
ENOREE RVR AT S-30-75
BE-018
LAURENS
AL
BIO
2013
BROAD
030501080106
ENOREE RIVER AT SC HWY 418
BE-019
LAURENS
AL
BIO
2016
BROAD
030501080201
BEAVERDAM CK AT S-30-97, 7 MI NE OF GRAY COURT
B-246
LAURENS
AL
CU
2016
BROAD
030501080206
ENOREE RVR AT SC 72, 121, & US 176, 1 MI NE WHITMIRE
B-053
NEWBERRY
AL
CU
2010
BROAD
030501080301
BEARDS FORK CK AT US 276 (1-385) 3.7 MI NNE OF CLINTON
B-231
LAURENS
AL
DO
2008
*
BROAD
030501080303
DUNCAN CREEK AT COUNTY RD 26, 4.5 M NE OF CLINTON
RS-01057
LAURENS
REC
FC
2013
BROAD 1030501080501
KINGS CRK. AT US 176, DOWNSTREAM OF BRIDGE
B-799
NEWBERRY
AL
BIO
2016
BROAD
030501080502
ENOREE RVR AT S-36-45 3.5 MI AB JCT WITH BROAD RVR
B-054
NEWBERRY
AL
I CU
2016
CATAWBA
030501011502
LAKE WYLIE AB MILL CK ARM AT END OF S-46-557
CW-197
YORK
AL
CU
2012
CATAWBA
030501011504
BROWN CRK AT S-46-228 (GUINN ST), 0.3 MI W OF OLD N. MAIN ST IN CLOVER
CW-105
YORK
AL
TURBIDITY
2012
CATAWBA
030501011504
BEAVERDAM CK AT S-46-152 8 MI E OF CLOVER
CW-153
YORK
AL
TURBIDITY
2017, 2017
CATAWBA
030501011505
CROWDERS CK AT S-46-564 NE CLOVER
CW-023
YORK
AL
CD, CU
2013
CATAWBA
030501011505
CROWDERS CREEK AT S-46-1104
CW-024
YORK
AL
BIO
2016
CATAWBA
030501011505
LK WYLIE, CROWDERS CK ARM AT SC 49 AND SC 274
CW-027
YORK
AL
CU
2015
CATAWBA
030501011506
ALLISON CK AT S-46-114
CW-249
YORK
AL
CU
2008
CATAWBA
030501011506
ALLISON CK AT S-46-114
CW-249
YORK
REC
FC
2013
CATAWBA
030501030103
SUGAR CK US OF CONFLUENCE W/ MCALPINE CK
CW-246
YORK
AL
BIO
2013
CATAWBA
030501030107
MCALPINE CK AT S-29-64
CW-064
LANCASTER
AL
BIO
12

2006 SC List of Impaired Waters by 12-Digit HUC
TMDLTARGET
DATE(S) ++
2010
NOTE
BASIN
CATAWBA
HUC
030501030108
LOCATION
STEELE CK AT S-46-22 N OF FORT MILL
STATION
CW-009
COUNTY
YORK
USE
AL
_ CAUSE
DO
2008
CATAWBA
030501030108
STEELE CK AT S-46-22 N OF FORT MILL
CW-009
YORK
REC
FC
2008
CATAWBA
030501030108
STEELE CK AT S-46-270
CW-011
YORK
REC
FC
2008
CATAWBA
030501030108
STEELE CK AT S-46-98
CW-203
YORK
REC
FC
2013
CATAWBA
030501030108
STEEL CR. AT US BY-PASS 21
CW-681
YORK
AL
BIO
2013
CATAWBA
030501030109
SUGAR CK AT SC 160 E OF FORT MILL
CW-013
LANCASTER
AL
BIO
2016
CATAWBA
030501030109
SUGAR CREEK AT S-46-36
CW-036
LANCASTER
AL
CU
2012
CATAWBA
030501030203
SIXMILE CREEK AT S-29-54
CW-176
LANCASTER
AL
TURBIDITY
2016, 2012
CATAWBA
030501030204
TWELVEMILE CK AT S-29-55 0.3 MI NW OF VAN WYCK
CW-083
LANCASTER
AL
CU, TURBIDITY
2010
CATAWBA
030501030302
CANE CK AT SC 200 5 MI NNE OF LANCASTER
CW-185 I
LANCASTER
AL
DO
2010
CATAWBA
030501030303
BEAR CK AT S-29-362 3.5 MI SE OF LANCASTER
CW-151 I
LANCASTER I
AL
DO
2010
#
CATAWBA
030501030304
GILLS CK AT US 521 NNW OF LANCASTER
CW-047
LANCASTER
AL
DO
2010
CATAWBA
030501030304
BEAR CK AT S-29-292 1.6 MI W OF LANCASTER
CW-131
LANCASTER
AL
DO
2010
CATAWBA
030501030305
CANE CK AT S-29-50
CW-017
1 LANCASTER
AL
DO
2013
CATAWBA
030501030305
CANE CR. AT SC 9 BYPASS
CW-210
LANCASTER
AL
BIO
2010
CATAWBA
030501030305
RUM CK AT S-29-187
CW-232
LANCASTER
AL
DO
2010, 2012
CATAWBA
030501030401
WILDCAT CK AT S-46-650
CW-006
YORK
AL
DO, TURBIDITY
2010, 2012
CATAWBA
030501030401
WILDCAT CK AT S-46-998 9 MI ENE OF MCCONNELLS
CW-096
YORK
AL
DO, TURBIDITY
2012
CATAWBA
030501030401
TOOLS FORK AT S-46-195 7 MI NW OF ROCK HILL
CW-212
YORK
AL
TURBIDITY
2013
CATAWBA
030501030402
FISHING CK AT S-46-347 DS YORK WWTP
CW-005
YORK
AL 1
BIO
2016
CATAWBA
030501030402
FISHING CREEK AT S-46-503
CW-225
YORK
AL 1
CU
2013
I CATAWBA
030501030403
STONEY FORK CRK. AT SC 121 & 72
CW-697
YORK
AL I
BIO
2014
CATAWBA
030501030404
LAKE OLIPHANT, FOREBAY EQUIDISTANT FROM DAM AND SHORELINES
CL-021
CHESTER
AL
CHLA
2013
#
I CATAWBA
030501030406
SOUTH FORK OF FISHING CRK. AT SR 50
CW-007
CHESTER
AL I
BIO
2013
CATAWBA
030501030407
FISHING CR. AT SR 655
CW-654
YORK
AL
BIO
2013
CATAWBA
030501030407
TAYLORS CRK. AT SR 735
CW-695
YORK
AL
BIO
2016
CATAWBA
030501030408
(TINKERS CK AT S-12-599
CW-234
CHESTER
I AL I
CU
2016
CATAWBA
030501030502
ROCKY CK AT S-12-335 3.5 MI E OF CHESTER
CW-002
CHESTER
AL
CU
2010
CATAWBA
030501030502
GRASSY RUN BR AT SC 72 1.6 MI NE CHESTER
CW-088
CHESTER
AL
I D0
2013
I CATAWBA
030501030503
IBEAVER DAM CRK. AT SR 555
I CW-691
I CHESTER
AL
BIO
2008, 2008, 2012
CATAWBA
030501030505
CEDAR CK RESERVOIR/ROCKY CK AT S-12-141 SE OF GREAT FALLS
CW-175
CHESTER
AL
D0, TP,
TURBIDITY
2016
CATAWBA
030501030505
ROCKY CK AT S-12-138
CW-236
CHESTER
AL
CU
2016
#
CATAWBA
030501030603
IWAXHAW CK AT S-29-29
CW-145
LANCASTER
AL
CU
13

2006 SC List of Impaired Waters by 12-Digit HUC
TMDL TARGET
DATES) ++
2016
NOTE
BASIN
CATAWBA
HUC
030501030604
LOCATIO I
CATAWBA RVR AT SC 5 AB BOWATER
=' -. 'iii,,J
CW-041
'' `"
LANCASTER
- -:i_
AL
j�1=
CU -
2013
CATAWBA
030501030604
GREENE CREEK AT S-12-465 8.2 MI N OF FORT LAWN
RS-03511
CHESTER
AL
BIO
2007
CATAWBA
030501030604
GREENE CREEK AT S-12-465 8.2 MI N OF FORT LAWN
RS-03511
CHESTER
REC
FC
2008
CATAWBA
030501030606
FISHING CK RES 2 MI BL CANE CREEK
CW-016F
CHESTER
AL
TP
2008
CATAWBA
030501030606
FISHING CK RES 75 FT AB DAM NR GREAT FALLS
CW-057
CHESTER
AL
TP
2008, 2008, 2008
CATAWBA
030501030606
CEDAR CK RESERVOIR AT UNIMP RD AB JCT WITH ROCKY CK
CW-174
CHESTER
AL
DO, TN, TP
2008, 2008
CATAWBA
030501030606
CEDAR CK RES 2.15 M SE OF GREAT FALLS
RL-01007
LANCASTER
AL
CHLA, DO
2008
CATAWBA
030501030606
FISHING CK RES 3.8 M S OF FORT LAWN OFF W SHORE OF THE TOWN OF
LAKE VIEW
RL-01012
CHESTER
AL
CHLA
2008
CATAWBA
030501030606
CEDAR CK RES FROM W OF BIG ISL 7 MI BELOW ROCKY CK CONFL
RL-02319
CHESTER
AL
TP
2008
CATAWBA
030501030606
CEDAR CK RES 0.15 MI SE OF S TIP PICKETT ISLAND
RL-02452
LANCASTER
AL
TP
2008, 2008, 2012
CATAWBA
030501030606
GREAT FALLS RESERVOIR 0.9 MI NE OF GREAT FALLS
RL-03332
CHESTER
AL
TN, TURBIDITY
2016, 2008, 2012
CATAWBA
030501030606
CEDAR CREEK RESERVOIR 0.3 MI NE OF DAM AND W OF BIG ISLAND
RL-03351
CHESTER
AL
CU, TP,
TURBIDITY
2008, 2012
CATAWBA
030501030606
CEDAR CREEK RESERVOIR 1.9 MI SE OF GREAT FALLS AND E OF BIG ISLAND
RL-03353
CHESTER
AL
TP, TURBIDITY
2008, 2012
CATAWBA
030501030606
GREAT FALLS RSVR 1 MI NE OF GREAT FALLS
RL-03458
CHESTER
AL
TP, TURBIDITY
2008
CATAWBA
030501030606
CEDAR CREEK RESERVOIR 2.2 MI SE OF GREAT FALLS SE OF BOWDEN ISLAND
RL-04375
LANCASTER
AL
TP
2008
CATAWBA
030501030606
CEDAR CREEK RESERVOIR 1.25 MI ESE OF GREAT FALLS NW OF HILL ISLAND
RL-04379
CHESTER
AL
TP
2010
CATAWBA
030501040102
LITTLE WATEREE CK AT S-20-41 5 MI E OF WINNSBORO
CW-040
FAIRFIELD
AL
DO
2007
*
CATAWBA
030501040102
LITTLE WATEREE CK AT S-20-41 5 MI E OF WINNSBORO
CW-040
FAIRFIELD
REC
FC
2010
CATAWBA
030501040105
BIG WATEREE CK AT US 21
CW-072
I FAIRFIELD
I AL
DO
2008, 2012
CATAWBA
030501040106
CEDAR CK RESERVOIR 100 M N OF DAM
CW-033
LANCASTER
AL
TP, TURBIDITY
2008, 2008, 2012
CATAWBA
030501040106
LK WATEREE HEADWATERS APPROX 50 YDS DS CONFL CEDAR CK
CW-231
LANCASTER
AL
PH, TP,
TURBIDITY
2008, 2008, 2008
CATAWBA
030501040108
LK WATEREE AT S-20-101 11 MI ENE WINNSBORO
CW-208
FAIRFIELD
AL
CHLA, PH, TP
2008
CATAWBA
030501040108
DUTCHMANS CK AT S-20-106
RS-02321
FAIRFIELD
REC
FC
2008
CATAWBA
030501040111
LK WATEREE IN FOREBAY EQUIDISTANT FROM DAM AND SHORELINES
CL-089
KERSHAW
AL
PH
2008, 2008
CATAWBA
030501040111
LK WATEREE AT END OF S-20-291
CW-207
FAIRFIELD
AL
PH, TP
2008, 2008
CATAWBA
030501040111
LK WATEREE AT SMALL ISLAND 2.3 MI N OF DAM
CV1t-209
KERSHAW
AL
PH, TP
2008, 2008
CATAWBA
030501040111
LAKE WATEREE 1.0 MI SW FROM MOUTH OF BEAVER CK
RL-02314
KERSHAW
AL
PH, TP
2008, 2008
CATAWBA
030501040111
LAKE WATEREE NEARSHORE ALONG S-28-802 OPP COLONEL CK CONFL
RL-03336
KERSHAW
AL
PH, TP
2008
*
CATAWBA
030501040202
GRANNIES QUARTER CK AT SC 97
I CW-237
KERSHAW
I REC
I FC
2010
CATAWBA
030501040206
BEAR CK AT S-40-82
CW-229
I RICHLAND
I AL
DO
2013
CATAWBA
030501040207
TWENTYFIVE MILE CK AT S-28-05 3.7 MI W OF CAMDEN
I CW-080
I KERSHAW
AL
1 BIO
2017
CATAWBA
030501040208
IWATEREE RIVER BELOW LAKE WATEREE DAM
CW-039
KERSHAW
FISH
I HG
2008
*
CATAWBA
1 030501040302
ILITTLE PINE TREE CREEK AT S-28-132
1 CW-223
I KERSHAW
REC
FC
2010
I CATAWBA
030501040304
WATEREE RVR AT US 1
CW-019
KERSHAW
AL
DO
2010
CATAWBA
030501040304
WATEREE RIVER AT I-20
CW-214
KERSHAW
AL
DO
2019
CATAWBA
030501040304
WATEREE RIVER AT I-20
CW-214
KERSHAW
FISH
HG
14

TMDLs Under Development
Page 1 of 1
Total Maximum Daily Load (TMDL) Development
Commencement of TMDLs
Development of a total maximum daily load(s) is currently underway for the area(s) listed in the
table below. Please send any data or information that supports the development of the TMDL to
Mihir Mehta. All data and information submitted, including characterizations of local conditions
that affect attainment of water quality standards, shall be considered before completing the TMDL.
Waterbody
County(ies)
Parameter
Water Quality Monitoring
Sites
Date of
Commencement
Fishing Creek
Reservoir
Chester
Phosphorus
CW-016F, CW-057
prior to 05/20/05
Great Falls Tailrace Chester Phosphorus
CW-175 prior to 05/20/05
Cedar Creek Reservoir
Chester, Phosphorus
Lancaster
CW-174, CW-033
prior to 05/20/05
Lake Wateree
Fairfield,
Kershaw
Phosphorus & pH
CW-207, CW-209
prior to 05/20/05
Lake Wateree
Fairfield
Phosphorus, pH, &
Chl-a
CW-208
prior to 05/20/05
Steele Creek York Fecal Coliform CW-009, CW-011, CW-203 08/22/06
Chinquapin Creek Aiken
Fecal Coliform E-091
09/01/06
N. Fork Edisto River Aiken
Fecal Coliform E-084, E-102
09/01/06
Reedy River
Laurens
Phosphorus
S-308, S-311
prior to 05/20/05
Reedy River
Greenville,
Laurens
Fecal Coliform
S-013, S-018, S-021, S-067,
S-070, S-072, S-073, S-091,
prior to 11/21/2006
http://www.scdhec.net/eqc/water/tmdl/tmdlsud.html 12/18/2006

Solubility of oxygen in water in equilibrium with air at 760mm Hg pressure and 100% relative humidity
(Le. oxygen values at 100% saturation for various temperatures)
Instructions:
Value in red represents the DO (mg/L) at 100% saturation for a temperature of 23.2 °C
T deg C
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
0
14.6
14.65
14.52
14.48
14.44
14.4
14.36
14.33
14.29
14.25
1
14.21
14.17
14.13
14.09
14.05
14.02
13.98
13.94
13.9
13.87
2
13.83
13.79
13.75
13.72
13.68
13.64
13.61
13.57
13.54
13.5
3
13.46
13.43
13.39
13.36
13.32
13.29
13.25
13.22
13.18
13.15
4
13.11
13.08
13.04
13.01
12.98
12.94
12.91
12.88
12.84
12.81
5
12.78
12.74
12.71
12.68
12.64
12.61
12.58
12.55
12.52
12.48
6
12.45
12.45
12.39
12.36
12.33
12.29
12.26
12.23
12.2
12.17
7
12.14
12.11
12.08
12.05
12.02
11.99
11.96
11.93
11.9
11.87
8
11.84
11.81
11.78
11.76
11.73
11.7
11.67
11.64
11.61
11.58
9
11.56
11.53
11.5
11.47
11.44
11.42
11.39
11.36
11.34
11.31
10
11.28
11.25
11.23
11.2
11.17
11.15
11.12
11.1
11.07
11.04
11
11.02
10.99
10.97
10.94
10.91
10.89
10.86
10.84
10.81
10.79
12
10.76
10.74
10.72
10.69
10.67
10.64
10.62
10.59
10.57
10.55
13
10.54
10.5
10.47
10.45
10.43
10.4
10.38
10.36
10.34
10.31
14
10.29
10.27
10.24
10.22
10.2
10.18
10.15
10.13
10.11
10.09
15
10.07
10.04
10.02
10
9.98
9.96
9.94
9.92
9.89
9.87
16
9.85
9.83
9.81
9.79
9.77
9.75
9.73
9.71
9.69
9.67
17
9.65
9.63
9.61
9.59
9.57
9.55
9.53
9.51
9.49
9.47
18
9.45
9.43
9.41
9.39
9.37
9.36
9.34
9.32
9.3
9.28
19
9.26
9.24
9.23
9.21
9.19
9.17
9.15
9.13
9.12
9.1
20
9.08
9.06
9.05
9.03
9.01
8.99
8.89
8.96
8.94
8.92
21
8.91
8.89
8.87
8.86
8.84
8.82
8.81
8.79
8.77
8.76
22
8.74
8.72
8.71
8.69
8.67
8.66
8.64
8.63
8.61
8.59
23
8.58
8.56
..`::::
8.53
8.51
8.5
8.48
8.47
8.45
8.44
24
8.42
8.41
8.39
8.38
8.36
8.35
8.33
8.32
8.3
8.29
25
8.27
8.26
8.24
8.23
8.21
8.2
8.18
8.17
8.16
8.14
26
8.13
8.11
8.1
8.08
8.07
8.06
8.04
8.03
8.01
8
27
7.99
7.97
7.96
7.94
7.93
7.92
7.9
7.89
7.88
7.86
28
7.85
7.84
7.82
7.81
7.8
7.78
7.77
7.76
7.74
7.73
29
7.72
7.7
7.69
7.68
7.66
7.65
7.64
7.63
7.61
7.6
30
7.59
7.57
7.56
7.55
7.54
7.52
7.51
7.5
7.49
7.47

WWTP Discharge Characteristics vs Instream do
16.00
14.00
12.00
10.00
a)
8.00 -
a�
0
N 6.00
4.00
2.00
6.
5.
4.
3.
2.
1
0.00 0.
Jan-01 Jul-01 Jan-02 JuI-02 Jan-03 Jul-03 Jan-04 Jul-04 Jan-05 JuI-05 Jan-06 Jul-06 Jan-07
Date
Downstream DO Effluent DO WWTP Flow
Discharge (mgd)

Re: Fw: Six Mile Creek, South Carolina
Subject: Re: Fw: Six Mile Creek, South Carolina
From: Toby D Feaster <[e-mail]>
Date: Wed, 7 Mar 2007 08:19:30 -0500
To: [e-mail]
CC: John C Weaver <[e-mail]>, Noel M Hurley <[e-mail]>, Toby D Feaster <[e-mail]>
Ms. Fields,
We have two partial -record stations on Six Mile Creek for which !ow -flow statistics were computed in the mid 1980s. Unfortunately, the USGS has been unable to secure
cooperator funding to update low -flow statistics for South Carolina streams in recent years. Listed below is the information we have available for Six Mile Creek. This
information comes from the following USGS report:
Zalants, M.G., Low -flow characteristics of natural streams in the Blue Ridge, Piedmont, and upper Coastal Plain physiographic provinces of South Carolina: U.S.
Geological Survey Water -Resources Investigations Report 90-4188.
The report is available on-line at the following address:
http://pubs.er.usgs.gov/usgspubs/wri/wri904188
Hope this helps,
Toby
Table 1.-Seren>-dMy low -flow discharae estimates for partial -record stations In South Carolina and continuous -record
index stations in South Carolina, North Carolina, and G.orgia-.Continued
Ng, Mini*ii average distltsrpe for seven consecutive days tits a reaarence interval of 2 years; 7Qt •
minimum average discharge for seven consecutive days lours recurrence interval of 10 years;
unavailable
dashes indicate data available or not applicable; '/s, cubic feet per second;
mi, mile; mil, square Mile; let, latitude; Long, longitude; 4, less
Map
refer-
ence Station Station
number number name
location
Index 70a 70..
Drainage
station 7oa 701• per per
(tat') number (ft'/s) (ft'/s) mi' mi'
•
78 021466701 Sixmile Creek let 34'52'29` 9.38
near Catawba Long 80'5352"
York County,
at county road 188,
1.7 mi NE of Catawba,
and 1.8 mi upstream
from Catawba River.
79 021469901 Six Nile Creek Let 34955 90N 39.6 02149000 3.0 1.3 .08 <.1
near Van wyck Long 80'48 55*
lancsster County,
at county road 161,
0.2 Mi upstream from
Tuelveaile Creek, and
4.5 mi !E of Van tydc.
Toby D. Feaster
Hydrologist (Engineer)
U.S Department of the Interior
U.S. Geological Survey
South Carolina Water Science Center
Clemson Field Office
405 College Ave., Suite 200
Clemson, SC 29631
Email: [e-mail]
Phone: [phone]
Fax: [phone]
John C WeavedWRDNSGSJDOI
03/06/2007 12:01 PM
Toby,
02170400 .84 .33 .W .05
To Toby D FeastedWRD/USGS/DOI@USGS
cc Noel M Hurley/WRD/USGS/00I0USGS, John C Weaver/WRD/USGS/DOIaUSGS
Subject Fw: Six Mile Creek, South Carolina
Would you be able to check on any data you may have for this stream and assist Ms. Fields with what she is seeking?
1 of 2 + 3/20/2007 1:34 PM

Re: Fw: Six Mile Creek, South Carolina
JCWeaver
J. Curtis Weaver, Hydrologist, PE
USGS North Carolina Water Science Center
3916 Sunset Ridge Road
Raleigh, NC 27607
Telephone: [phone] // Fax: [phone]
E-mail address — [e-mail]
Internet address — http://nc.water.usgs.gov/
---- Forwarded by John C WeaverlWRD/USGS/D01 on 03/06/2007 11:56 AM
Toya Fields <[e-mail]
03/06/200711:07 AM
Hi Curtis,
Would you happen to have any streamflow data for Six Mile Creek in South
Carolina? I'm interested in flows at its confluence with Twelvemile
Creek. The lat/long is 34 54 58 / 80 48 43. I'm not sure of the
drainage area so I'm looking for 7Q10 (summer and winter) and Qavg. I
don't have any South Carolina data and I'm not sure where to look.
Thanks for your help.
Toya
Toya Fields - toya.fields8ncmail.net
Environmental Engineer I
Western NPDES Program
Division of Water Quality
Tel: [phone] x 551
Fax: [phone]
To John C Weaver <[e-mail]>
cc
Subject Six Mile Creek, South Carolina
2 of 2 3/20/2007 1:34 PM

- c
elevation 2:11 ft
In P-0.018092
P 0.9820706
0.15 km
Date
Temp.
CC)
Streamflow
cfs
DO
(mglL)
04/02/01
11.2
27
10.20
04/09/01
19.0
12
7.07
04/16/01
16.2
8.2
7.18
04/23/01
16.2
7
7.14
04/30/01
14.5
5.8
7.58
05/07/01
16.9
3.9
6.18
05/14/01
17.4
3.6
5.79
05/21/01
20.9
2.7
3.83
05/29/01
18.2
10
7.20
06/04/01
20.2
5.3
5.66
06/06/01
22.8
3.2
4.38
06/07/01
22.9
2.8
3.92
06/11/01
20.8
2.3
3.95
06/12/01
21.2
2.1
3.73
06/14/01
21.5
11
4.84
06/18/01
21.5
5.7
5.41
06/20/01
22.1
2.2
'4.26
06/21/01
22.7
1.7
3.93
06/25/01
22.0
2.5
4.88
06/27/01
22.5
6.6
5.92
06/28/01
21.8
4.2
4.75
07/02/01
24.1
0.97
3.27
07/03/01
23.2
1.4
3.41
07/04/01
23.5
12
6.95
07/09/01
23.3
1.2
4.39
07/11/01
24.5
0.82
3.35
07/12/01
23.7
0.68
3.37
07/16/01
21.7
1.4
5.19
07/18/01
23.0
0.59
4.30
07/19/01
22.6
0.48
3.42
07/23/01
21.9
0.49
2.91
07/25/01
22.5
6
5.27
07/26/01
22.1
6.5
6.44
07/30/01
22.3
0.6
3.74
07/31/01
22.4
0.62
3.44
08/01/01
22.2
0.52
3.82
08/06/01
24.2
0.07
3.00
08/07/01
24.7
0.08
2.68
08/09/01
25.9
0.17
2.24
08/13/01
24.6
0.71
3.36
08/14/01
23.9
0.25
2.83
08/16/01
23.2
0.22
2.62
08/20/01
25.3
0.2
2.32
08/21/01
23.2
0.17
2.21
08/23/01
23.5
0.06
2.18
08/27/01
24.5
0.04
2.87
08/28/01
22.3
0.07
2.37
08/30/01
24.0
0.07
1.59
09/04/01
20.7
32
5.66
09/05/01
21.1
16
5.98
09/06/01
21.3
4.2
5.50
09/10/01
22.6
0.17
3.17
09/11/01
22.5
0.14
2.74
09/13/01
21.0
0.08
2.74
09/17/01
17.9
0.03
3.16
09/18/01
16.5
0.02
3.11
09/20/01
19.3
0.23
3.66
09/24/01
20.6
58
5.29
09/25/01
19.4
33
6.85
09/27/01
15.0
2.8
6.99
10/02/01
13.7
2
4.71
10/08/01
12.5
2.1
6.97
10/15/01
18.0
41
6.08
10/22/01
14.1
0.29
4.00
10/29/01
8.1
0.16
2.22
75th % 23.2
Cp Equilibrium oxygen concentration at nonstandard pressure, mg/L
C' Equilibrium oxygen concentration at standard pressure of 1 atm, mg/L
P nonstandard pressure, atm, relative to standard partial pressure
Inverse Pwv Partial pressure of water vapor, atm, computed from
Cp I % sat ( Temp In Pwv = 11.8571 - (3840.70/T) - (216,961/T2)
10.78 94.60 8.928571 where T = temperature, °K
9.11 77.58 5 263158 0 0.000975 - (1.426 X 104 t) + (6.436 x 104 t2)
9.66 74.35 6.17284 t temperature °C
9.66 73.94 6.17284
10.02 75.68 6.896552
9.52 64.94 5.91716 To calculate percent saturation:
9.42 61.48 5.747126
8.77 43.65 4 784689 Determine nonstandard atmospheric pressure, P (atm), at altitude, h (km).
9.26 77.73 5.494505 In P = 5.25 In (1- h/44.3)
8.90 63.62 4 950495
8.46 51.79 4 385965 Calculate the equilibrium oxygen concentration at nonstandard pressure.
8.44 46.44 4 366812
8.79 44.93 4.807692 Cp = C' x Pr1-Pwv/P) (1-0P)�
8.72 42.76 4 716981 [1-Pwv/P)
(1-0)
8.67 55.81 4.651163
8.67 62.38 4 651163 Determine % saturation based on DO concentration (mg/L)
8.57 49.70 4.524887
8.47 46.38 4 405286 % saturation = (100 x DO) / Cp
8.59 56.82 4.545455
8.51 69.60 4 444444
8.62 55.09 4 587156
8.25 39.63 4149378
8.39 40.63 4.310345
8.35 83.28 4 255319
8.38 52.40 4.291845
8.19 40.90 4 081633
8.31 40.53 4.219409
8.64 60.08 4 608295
8.43 51.04 4.347826
8.49 40.28 4.424779
8.61 33.82 4.56621
8.51 61.96 4 444444
8.57 75.13 4.524867
8.54 43.80 4 484305
8.52 40.36 4.464286
8.56 44.65 4 504505
8.24 36.42 4.132231
8.16 32.84 4 048583
7.98 28.07 3.861004
8.17 41.10 4 065041
8.28 34.17 4 1841
8.39 31.22 4 310345
8.07 28.75 3 952569
8.39 26.33 4 310345
8.35 26.12 4255319
8.19 35.04 4 081633
8.54 27.76 4.484305
8.27 19.23 4166667
8.81 64.25 4.830918
8.74 68.42 4 739336
8.71 63.17 4.694836
8.49 37.34 4 424779
8.51 32.21 4 444444
8.76 31.29 4 761905
9.32 33.90 5 566592
9.60 32.41 6 060606
9.06 40.40 5.181347
8.83 59.93 4 854369
9.04 75.77 5.154639
9.91 70.55 6 666667
10.19 46.21 7 29927
10.47 66.58 8
9.30 65.37 5 555556
10.10 39.59 7 092199
11.60 19.13 12.34568
median 46.21
mean
DO © 100% saturation for above listed temperature
Upstream DO Input for level B model
50.02
MOM
8.55 mcVL
mgL

60
50
40
20
10
0
Mar-01
Apr-01
Streamflow versus DO % Saturation
May-01
Jun-01
Twelvemile Creek is experiencing an
average DO percent saturation of 50%.
This seems to be primarily affected by
streamflow (rather than temperature, as
might be expected)
Date
Jul-01
Aug-01
—Streamflow Inverse Temp — Percent Saturation
Sep-01
100
90
- 80
- 70
- 60
50
— 40
30
20
10
Oct-01
0
Percent Saturation

SUMMER
MODEL RESULTS
Discharger : TWELVEMILE CREEK WWTP
Receiving Stream : TWELVEMILE CREEK
The End D.O. is
The End CBOD is
The End NBOD is
7.02 mg/l.
2.30 mg/l.
0.68 mg/l.
Segment 1
Reach 1
Reach 2
Reach 3
Reach 4
DO Min
WLA
CBOD
(mg/1) Milepoint Reach # (mg/1)
5.89
7.80
3
7.00
0.00
0.00
0.00
WLA
NBOD
(mg/1)
4.50
0.00
0.00
0.00
WLA
DO Waste Flow
(mg/1) (mgd)
6.00
0.00
0.00
0.00
6.00000
0.00000
0.00000
0.00000

*** MODEL SUMMARY DATA ***
Discharger
Receiving Stream :
Summer 7Q10
Design Temperature:
TWELVEMILE CREEK WWTP
TWELVEMILE CREEK
0.1
26.0
Subbasin : 030838
Stream Class: C
Winter 7Q10 : 1.5
LENGTH SLOPE VELOCITY 1 DEPTH Kd I Kd I Ka I Ka 1 KIT
mile ft/mi fps. ft design @20° design @20° design
Segment 1
Reach 1
2.30
4.35
0.227 11.66 0.29
0.22
2.03 I 1.781 0.48
Segment 1
Reach 2
2.90
3.45
0.213
1.72
0.28
0.22
1.50
1.32
0.48
Segment 1
Reach 3
4.50
2.20
0.162
1.97 1 0.27
0.21
0.73
0.64
0.48
Segment 1
Reach 4
2.50
4.00
0.193
1.81
0.28
0.21
1.58
1.39
0.48
Flow
cfs
Segment 1 Reach 1
Waste
Headwaters
Tributary
* Runoff
9.300
0.100
0.000
0.000
Segment 1 Reach 2
Waste 0.000
Tributary 0.000
* Runoff 0.000
Segment 1 Reach 3
Waste 0.000
Tributary 0.050
* Runoff 0.000
Segment 1 Reach 4
Waste 0.000
Tributary 0.000
*Runoff 0.000
CBOD
mg/1
7.000
2.000
2.000
2.000
0.000
2.000
2.000
0.000
2.000
2.000
NBOD I D.O.
mg/1 mg/1
4.500
1.000
1.000
1.000
0.000
1.000
1.000
0.000
1.000
1.000
0.000 I 0.000
2.000 1.000
2.000 1.000
7.300
7.300
0.000
7.300
7.300
0.000
7.300
7.300
0.000
7.300
7.300

SUMMER
1
Seg #
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
Reach # I Seg Mi I D.O. I CBOD I NBOD I Flow I
1 0.00 5.98 6.95 4.46 9.40
1 0.10 5.98 6.89 4.41 9.40
1 0.20 5.99 6.84 4.35 9.40
1 0.30 6.00 6.79 4.29 9.40
1 0.40 6.01 6.73 4.24 9.40
1 0.50 6.01 6.68 4.19 9.40
1 0.60 6.02 6.63 4.13 9.40
1 0.70 6.03 6.58 4.08 9.40
1 0.80 6.04 6.53 4.03 9.40
1 0.90 6.05 6.48 3.98 9.40
1 1.00 6.07 6.43 3.93 9.40
1 1.10 6.08 6.38 3.88 9.40
1 1.20 6.09 6.33 3.83 9.40
1 1.30 6.10 6.28 3.78 9.40
1 1.40 6.11 6.23 3.73 9.40
1 1.50 6.13 6.18 3.68 9.40
1 1.60 6.14 6.14 3.64 9.40
1 1.70 6.15 6.09 3.59 9.40
1 1.80 6.17 6.04 3.54 9.40
1 1.90 6.18 6.00 3.50 9.40
1 2.00 6.19 5.95 3.46 9.40
1 2.10 6.21 5.90 3.41 9.40
1 2.20 6.22 5.86 3.37 9.40
1 2.30 6.24 5.81 3.33 9.40
2 2.30 6.24 5.81 3.33 9.40
2 2.40 6.23 5.77 3.28 9.40
2 2.50 6.22 5.72 3.24 9.40
2 2.60 6.21 5.67 3.19 9.40
2 2.70 6.20 5.63 3.15 9.40
2 2.80 6.20 5.58 3.11 9.40
2 2.90 6.19 5.54 3.06 9.40
2 3.00 6.19 5.49 3.02 9.40
2 3.10 6.19 5.45 2.98 9.40
2 3.20 6.18 5.40 2.94 9.40
2 3.30 6.18 5.36 2.90 9.40
2 3.40 6.18 5.31 2.86 9.40
2 3.50 6.19 5.27 2.82 9.40
2 3.60 6.19 5.23 2.78 9.40
2 3.70 6.19 5.19 2.75 9.40
2 3.80 6.19 5.14 2.71 9.40
2 3.90 6.20 5.10 2.67 9.40
2 4.00 6.20 5.06 2.64 9.40
2 4.10 6.21 5.02 2.60 9.40
2 4.20 6.21 4.98 2.56 9.40
2 4.30 6.22 4.94 2.53 9.40
2 4.40 6.23 4.90 2.50 9.40
2 4.50 6.24 4.86 2.46 9.40
2 4.60 6.24 4.82 2.43 9.40
2 4.70 6.25 4.78 2.39 9.40
2 4.80 6.26 4.74 2.36 9.40
2 4.90 6.27 4.70 2.33 9.40
2 5.00 6.28 4.67 2.30 9.40
2 5.10 6.29 4.63 2.27 9.40
2 5.20 6.30 4.59 2.24 9.40
3 5.20 6.31 4.58 2.23 9.45
3 5.30 6.27 4.53 2.19 9.45

1 3 5.40 6.23 4.48 2.15 9.45
` 1 3 5.50 6.20 4.44 2.11 9.45
1 3 5.60 6.17 4.39 2.08 9.45
1 3 5.70 6.14 4.35 2.04 9.45
1 3 5.80 6.12 4.30 2.00 9.45
1 3 5.90 6.09 4.26 1.97 9.45
1 3 6.00 6.07 4.21 1.93 9.45
1 3 6.10 6.05 4.17 1.90 9.45
1 3 6.20 6.03 4.13 1.86 9.45
1 3 6.30 6.01 4.08 1.83 9.45
1 3 6.40 5.99 4.04 1.80 9.45
1 3 6.50 5.98 4.00 1.77 9.45
1 3 6.60 5.97 3.96 1.73 9.45
1 3 6.70 5.95 3.92 1.70 9.45
1 3 6.80 5.94 3.88 1.67 9.45
1 3 6.90 5.93 3.84 1.64 9.45
1 3 7.00 5.92 3.80 1.61 9.45
1 3 7.10 5.92 3.76 1.59 9.45
1 3 7.20 5.91 3.72 1.56 9.45
1 3 7.30 5.90 3.68 1.53 9.45
1 3 7.40 5.90 3.64 1.50 9.45
1 3 7.50 5.90 3.61 1.48 9.45
1 3 7.60 5.89 3.57 1.45 9.45
1 3 7.70 5.89 3.53 1.42 9.45
1 3 7.80 5.89 3.50 1.40 9.45
1 3 7.90 5.89 3.46 1.37 9.45
1 3 8.00 5.89 3.43 1.35 9.45
1 3 8.10 5.90 3.39 1.32 9.45
1 3 8.20 5.90 3.35 1.30 9.45
1 3 8.30 5.90 3.32 1.28 9.45
1 3 8.40 5.91 3.29 1.25 9.45
1 3 8.50 5.91 3.25 1.23 9.45
1 3 8.60 5.92 3.22 1.21 9.45
1 3 8.70 5.92 3.19 1.19 9.45
1 3 8.80 5.93 3.15 1.17 9.45
1 3 8.90 5:93 3.12 1.15 9.45
1 3 9.00 5.94 3.09 1.13 9.45
1 3 9.10 5.95 3.06 1.11 9.45
1 3 9.20 5.96 3.03 1.09 9.45
1 3 9.30 5.97 2.99 1.07 9.45
1 3 9.40 5.98 2.96 1.05 9.45
1 3 9.50 5.99 2.93 1.03 9.45
1 3 9.60 6.00 2.90 1.01 9.45
1 3 9.70 6.01 2.87 0.99 9.45
1 4 9.70 6.01 2.87 0.99 9.45
1 4 9.80 6.07 2.85 0.98 9.45
1 4 9.90 6.13 2.82 0.96 9.45
1 4 10.00 6.19 2.80 0.95 9.45
1 4 10.10 6.24 2.77 0.94 9.45
1 4 10.20 6.30 2.75 0.92 9.45
1 4 10.30 6.35 2.72 0.91 9.45
1 4 10.40 6.40 2.70 0.89 9.45
1 4 10.50 6.44 2.67 0.88 9.45
1 4 10.60 6.49 2.65 0.87 9.45
1 4 10.70 6.53 2.63 0.85 9.45
1 4 10.80 6.58 2.60 0.84 9.45
1 -4 10.90 6.62 2.58 0.83 9.45
1 4 11.00 6.65 2.56 0.82 9.45
1 4 11.10 6.69 2.53 0.80 9.45
1 4 11.20 6.73 2.51 0.79 9.45

1 1
1
1
1
1
1
1
1
1
1
Seg #
4 11.30
4 11.40
4 11.50
4 11.60
4 11.70
4 11.80
4 11.90
4 12.00
4 12.10
4 12.20
Reach # I Seg Mi
6.76
6.79
6.83
6.86
6.89
6.91
6.94
6.97
6.99
7.02
D.O.
2.49
2.47
2.45
2.42
2.40
2.38
2.36
2.34
2.32
2.30
CBOD
0.78
0.77
0.76
0.75
0.73
0.72
0.71
0.70
0.69
0.68
NBOD
1
9.45
9.45
9.45
9.45
9.45
9.45
9.45
9.45
9.45
9.45
Flow I

RE: Union Co spec request
Subject: RE: Union Co spec request
From: "Struve, James N." <[e-mail]>
Date: Fri, 12 Jan 2007 16:07:19 -0500
To: <[e-mail]>
CC: "Susan Wilson" <[e-mail]>, "Berndt, Robert A." <[e-mail]>,
<[e-mail]>, <[e-mail]>
Good afternoon Toya.
Per Susan Wilson's email below, please see the attached spreadsheets which provide 12-Mile Creek dissolved
oxygen (DO) stream data for the years 2001 through 2006. Susan requested this data to assist DWQ in providing
speculative limits for expansion of Union County's Twelve Mile Creek WWTP from 6 to 9 mgd.
The spreadsheet entitled "12-Mile Creek Stream Data Summary Table" provides the date, time, stream
temperature, and stream DO levels for three (3) locations within 12-Mile Creek — specifically, 50-feet upstream of
the plant's outfall, 1/4-mile downstream of the plant's outfall, and downstream of the plant's outfall where NC State
Road 1301 crosses 12-Mile Creek.
The spreadsheet entitled "Correlation Between Temp, Streamflow and DO level" looks at the relationship between
DO levels and stream temperatures to stream flow in 12-Mile Creek for the period 2001 through 2004. It appears
that the USGS stream gauge was taken out of service in February 2004. Based upon our analysis, there appears
to be a very high correlation between very low stream flow and low DO. For example, 96% of all mean stream
flow readings less than 1.5 cfs coincided with DO levels under 5 mg/L. Conversely, stream flows above 1.5 cfs
coincided with DO levels under 5 mg/L or less in Tess than 11 % of the readings.
Please let me know if you require additional information to facilitate to determination.
Regards,
Jim
James N. Struve, P.E.
Senior Associate
Hazen and Sawyer, P.C.
4944 Parkway Plaza Boulevard, Suite 375
Charlotte, NC 28217
Office [phone]
CeII [phone]
Direct [phone]
Fax [phone]
Email [e-mail]
From: Susan Wilson [mailto:[e-mail]]
Sent: Wednesday, January 03, 2007 11:35 AM
To: [e-mail]
Cc: Struve, James N.; Berndt, Robert A.; [e-mail]; Toya Fields
Subject: Re: Union Co spec request
Thanks Mark. Toya Fields will be working on it, for your reference. You can send her the info via her
e-mail address above.
1of3
2/28/2007 11:37 AM

RE: Union Co spec request
[e-mail] wrote:
Good morning to all. An Excel file with stream data for Twelve Mile Creek is forthcoming in the near future.
Mark Tye
Assistant Public Works Director
(phone) 704 296-4215
(fax) 704 296-4232
Susan Wilson <[e-mail]>
12/19/2006 11:22 AM
Bob,
To [e-mail]
cc "Struve, James N." <[e-mail]>, [e-mail]
Subject Union Co spec request
We received your request for spec limits on behalf of Union Co. for the increase in wastewater flow for
12 Mile Creek. After having reviewed some further history in our files - there were issues in getting the
6 MGD phase approved (due to low stream flows and little instream monitoring data). So, in addition to
the very stringent TP limit with any expansion (likely even more stringent due to the SC TMDL) - there
is also a potential issue regarding instream D.O. The reason no speculative limits were given in the past
- was because of this issue and lack of information regarding the potential impact of the discharge.
DWQ granted the 6 MGD flow (basically at BAT limits) but could not/would not speculate on any
increase above that flow.
There should now be ample instream data that Union County has collected over the years. (and
hopefully Mark has this information in an excel file). We can't electronically retrieve a facility's
instream data from our current database. Could you guys compile that information for us? (that would
save us some time). It would behoove you to review that information - if there are multiple instances of
DO's below 5 mg/1 - that will be problematic. We'd want to look at the last 3-5 years of data.
Also - I'm going to assign this to someone in my group - but please keep in mind - we're short on WQ
modeling folks right now (loss of staff and one of my folks is on medical leave).
Thanks much. Have a good holiday.
Susan
2 of 3 2/28/2007 11:37 AM

1/6w 9 = '0'0 - 1/6w 5 = 'O'0 II wee sunnoa I weaEISUMO J
.p.a wBe tsdn
a;ea
90-Inr 90-Uef so-Inf 50-Uef bo-Inf vo-Uef Eo-Inr co-Uef z0-Inf z0-uur l0-Inr lo-Uer
00.0
uoi4eao7 uo pase8 ua6I(xp panfoss!Q weansui to uosiaedwo3
oo-z
00't7
00'9
v
b
00'9
oo.o I.
oo.z
oo.t71-
00'9

6.00
5.00
E 4.00
O
3.00
2.00
1.00
Magnification of Low Dissolved Oxygen Values
A
Jan-01 Jul-01 Jan-02 JuI-02 Jan-03 JuI-03 Jan-04 Jul-04 Jan-05 Jul-05 Jan-06 JuI-06
Date
Upstream D.O. Downstream I Downstream II D.O. = 5 mg/L D.O. = 6 mg/L

500
450
400
350 -
300
V
250
T.
200
150
100
50
0
Twelve Mile Creek Streamflow - Overview
\ice
tit
Jan-01 Apr-01 Jul-01 Oct-01 Jan-02 Apr-02 Jul-02 Oct-02 Jan-03 Apr-03 JuI-03 Oct-03 Jan-04 Apr-04
Date
—Streamflow —s7Q10 w7Q10 —Qavg

1000
100
10
0.1
Twelve Mile Creek Streamflow vs Minimum Flow Estimates- Log Scale
0.01 -
Jan-01 Apr-01 Jul-01 Oct-01 Jan-02 Apr-02 Jul-02 Oct-02 Jan-03 Apr-03 Jul-03 Oct-03 Jan-04 Apr-04
Date
—Streamflow s7Q10= 0.1 cfs w7Q10=1.5 cfs Qavg= 73 cfs

Streamflow (cfs)
100
90
80
70
60 -
50 -
40
30 -
20 -
10
0
J
Streamflow versus Dissolved Oxygen
(I)PSTI E
III
Jan-01 Apr-01 Jul-01 Oct-01 Jan-02 Apr-02 Jul-02 Oct-02 Jan-03 Apr-03 Jul-03 Oct-03 Jan-04 Apr-04 Jul-04 Oct-04
Date
— Streamflow — Dissolved Oxygen
16.00
15.00
14.00
13.00
12.00
11.00
10.00
9.00
8.00
7.00
6.00
5.00
4.00
3.00
2.00
1.00
0.00
Dissolved Oxygen (mg/L)

Union Co spec request
Subject: Union Co spec request
From: Susan Wilson <[e-mail]>
Date: Tue, 19 Dec 2006 11:22:40 -0500
To: [e-mail]
CC: "Struve, James N." <[e-mail]>, [e-mail]
Bob,
We received your request for spec limits on behalf of Union Co. for the increase in wastewater flow
for 12 Mile Creek. After having reviewed some further history in our files - there were issues in
getting the 6 MGD phase approved (due to low stream flows and little instream monitoring data).
So, in addition to the very stringent TP limit with any expansion (likely even more stringent due to
the SC TMDL) - there is also a potential issue regarding instream D.O. The reason no speculative
limits were given in the past - was because of this issue and lack of information regarding the
potential impact of the discharge. DWQ granted the 6 MGD flow (basically at BAT limits) but
could not/would not speculate on any increase above that flow.
There should now be ample instream data that Union County has collected over the years. (and
hopefully Mark has this information in an excel file). We can't electronically retrieve a facility's
instream data from our current database. Could you guys compile that information for us? (that
would save us some time). It would behoove you to review that information - if there are multiple
instances of DO's below 5 mg/1 - that will be problematic. We'd want to look at the last 3-5 years
of data.
Also - I'm going to assign this to someone in my group - but please keep in mind - we're short on
WQ modeling folks right now (loss of staff and one of my folks is on medical leave).
Thanks much. Have a good holiday.
Susan
Susan A. Wilson, P.E.
Supervisor, Western NPDES Program
(919) 733 - 5083, ext. 510
1617 Mail Service Center
Raleigh, NC 27699-1617
1 of 1 12/19/2006 11:25 AM

0025259
C0024937
Charlotte
970
CAW./ c; F Lpr
(ap,or. (, . l2— /Arc.=
NC0085359
(' Major NPDES
O Minor NPDES
2003 Use Support
USE RATING
Supporting
No Data
Impaired
Not Rated
Roads
00305
NC►'81621 'f
i� ' �C ► � 69520
NC0086169
C0085812
5,0 -,M P41(720
C0024333
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L;C
NC0043532
Keity
BLS B `
0,0(565749
NC0035041
�r NC0069841
NCO()

HAZEN AND SAWYER
Environmental Engineers & Scientists
December 14, 2006
Ms. Susan Wilson, Supervisor
Western NPDES Program
Division of Water Quality
N.C. Department of Environment
and Natural Resources
1617 Mail Service Center
Raleigh, North Carolina 27699-1617
1t..
v N�t'UIQL, •1v �..li I II1,,.
Twelve Mile Creek WWTP
Union County, North Carolina
NPDES Permit No. NC0085359
Dear Ms. Wilson:
Hazen and Sawyer, P.C.
4011 WestChase Blvd.
Suite 500
Raleigh, NC 27607
[phone]
[phone] (Fax)
Hazen and Sawyer is in the process of preparing an Engineering Report for expansion of the
Twelve Mile Creek Wastewater Treatment Plant (WWTP) from its current permitted capacity
of 6.0 mgd to a future expanded capacity of 9.0 mgd. We are hereby requesting speculative
NPDES discharge limits for the expanded capacity of 9.0 mgd in order to include this
information in the Engineering Report. We would also like to request speculative limits for
flows of 12 and 15 mgd in order to evaluate treatment facility requirements for future plant
expansions that may be required beyond the planning period for the Engineering Report.
Thank you for your review of this request for speculative limits and for your assistance on this
project.
Very truly yours,
HAZEN AND SAWYER, P.C.
Robert A. Berndt, P.E.
Senior Associate
JAB/mdb
cc: Ms. Christie Putman
Mr. Mark Tye
Mr. Jim Struve
SWilson 12.14.06 Ilr.
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Union County, NC - Twelve Mile Creek WWTP Expansion Beyond ...
gA(10160,4
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Subject: Union County, NC - Twelve Mile Creek WWTP Expansion Beyond 6 MGD - Meeting with
SC DHEC •
From: "Struve, James N." <[e-mail]
Date: Wed, 7 Mar 2007 19:08:34 -0500
To: <[e-mail]>
CC: <[e-mail]>, <montebmj @dhec.sc.gov>; <[e-mail]>, "Larry Turner"
<[e-mail]>, <[e-mail]>, <[e-mail]>, "Berndt, Robert
A." <[e-mail]>, "Parker, Michael D." <[e-mail]>,
"Taylor, Ronald L." <[e-mail]>, "Rohrbacher, Joe"
<jrohrbacher @ hazenandsawyer.com>
Good afternoon Susan.
This past Friday (March 2nd), Union County and Hazen and Sawyer met with Mike Montebello, Weijia Hu and
Larry Turner of SC DHEC. The purpose of the meeting was to discuss the expansion of the County's plant
beyond 6 mgd and to address any preliminary concerns/issues SC DHEC may have.
As you are aware, SC DHEC is in the process of calibrating their WARMF model which will assist them in
allocating waste loadings to existing and future NC/SC POTWs discharging into the Catawba River System. In
particular, SC DHEC is primarily concerned with Total Phosphorus (TP). Speculation is that the existing
established TP TMDLs will remain unchanged in order to meet the current SC TP lake standard of 0.06 mg/L.
Based upon an existing established TMDL of 20.85 Ibs/day at the Twelve Mile Creek WWTP, this will result in the
following effective TP concentrations for the various expansion scenarios:
Plant Rated Capacity, mgd
2.5
6.0
9.0
12.0
15.0
Effective TP Concentration, mg/L
1.00
0.42
0.28
0.21
0.17
Mike Montebello indicated that more than likely, SC DHEC will allocate a TP TMDL to NC. In turn, it will be NC's
responsibility to allocate this maximum daily limit to the specific NC POTWs discharging into the Catawba River
System. How this allocation is distributed to the NC POTWs is solely up to NC DWQ. If there is a reallocation of
TP by DWQ, then Union County would certainly expect to be equitably included.
When nitrogen limits was brought up for discussion, SC DHEC indicated that the implementation of Total Nitrogen
(TN) limits is not in the foreseeable future. Again, the biggest driver in SC is TP. In order for POTWs to meet the
TP TMDL, the final effluent must be devoid of solids, and as a result, conventional pollutants such as BOD and
TSS become less of a concern.
Specific water quality concerns with respect to 12 Mile Creek were also discussed. Currently, 12 Mile Creek is not
listed in the 303(d) impaired waters list for NC. Hazen and Sawyer recently compiled and sent NC DWQ stream
flow, temperature and dissolved oxygen (DO) data upstream and downstream of the Plant's discharge into 12
Mile Creek for the years 2001 to 2006. Hazen and Sawyer will also send this same data set to SC DHEC.
However, SC DHEC indicated that at his point and time, they are only concern with copper and turbidity levels
within 12 Mile Creek.
•
In summary, SC DHEC has no objections to the expansion of the County's Twelve Mile Creek WWTP. However,
Mike Montebello did request the following:
1. To be copied/notified of the speculative limits for the 9, 12, and 15 mgd flow scenarios upon issuance
by NC DWQ.
2. That the County performs a "Confirmatory WER" for copper and zinc following the 9 mgd expansion
if the process changes from completely stirred tank reactor (oxidation ditch) to plug flow (diffused air).
3. Any information from USGS that indicates/supports that the 7Q10 flow for the 12-Mile Creek is
greater than 0 cfs.
1 of 2 3/20/2007 1\.33 PM

• Twelve Mile Creek WWTP Expansion Beyond ...
9'
ease call or email me should you have any questions. We look forward to the receipt of the speculative limits
or 9, 12, and 15 mgd flow scenarios.
Regards,
Jim
James N. Struve, P.E.
Senior Associate
Hazen and Sawyer, P.C.
4944 Parkway Plaza Boulevard, Suite 375
Charlotte, NC 28217
Office [phone]
Cell [phone]
Direct [phone]
Fax [phone]
Email [e-mail]
2 of 2 3/20/2007 1:33 PM

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