NC0085359_Permit (Issuance)_20141121 (2)

NPDES DOCUMENT SCANNING COVER SHEET
NPDES Permit:
NC0085839
Twelve Mile Creek WWTP
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:
November 21, 2014
This document is printed on reuse paper - ignore arty
content on the reirerse side

NCDENR
North Carolina Department of Environment and Natural Resources
Pat McCrory John E. Skvarla, III
Governor Secretary
November 21, 2014
Mr. Ed Goscicki, Public Works Director
Union County Public Works
500 North Main Street, Suite 500
Monroe, NC 28112-4730
Subject: Issuance of NPDES Permit NC0085359
Renewal & Expansion
Twelve Mile Creek WWTP
Union County
Facility Class IV
Dear Mr. Ed Goscicki:
Division personnel have reviewed and approved your application for expansion and renewal of the subject
permit. Accordingly, we are forwarding the attached NPDES discharge permit. This permit is issued
pursuant to the requirements of North Carolina General Statute 143-215.1 and the Memorandum of
Agreement between North Carolina and the U.S. Environmental Protection Agency dated October 15, 2007
(or as subsequently amended).
Please note that the receiving stream is listed as an impaired waterbody on the North Carolina 2014 303(d)
Impaired Waters List for Fish Community (Fair Rating). Addressing impaired waters is a high priority with
the Division, and instream data will continue to be evaluated. If there is noncompliance with permitted
effluent limits and stream impairment can be attributed to your facility, then mitigative measures may be
required.
The following items are in response to the comment letter received from Union County on
October 30, 2014.
• The monitoring frequency for BOD5, TSS, and fecal coliform was listed incorrectly in the draft
permit. In accordance with DWR's Guidelines for Exceptionally Performing Facilities it was
changed to "twice per week." . The Guidelines do not provide for a twice per month allowance as
requested by the County.
• Instream sampling for DO and temperature remain in the permit. Continued instream sampling
will help to confirm the modeling predictions determined based upon the WWTP's flow
expansions.
• As requested, an Effluent Limitation and Monitoring Requirements sheet was added for a
permitted flow of 7.5 MGD. See section A. (2).
• The Standard Conditions from November 2011 have been attached to this permit.
• The modifications to the WER calculations have been received and will be evaluated separately
•
'from the processing of the permit modification and renewal. The Division will provide
comments on the modified WER calculations after other Division Branches have a chance to
review it.
' 1617 Mail Service Center, Raleigh, North Carolina 27699-1617
Phone: [phone] Internet: www.ncwaterquality.org
An Equal opportunity 1 Affirmative Action Employer— Made in part by recycled paper

Mr. Ed Goscicki, Public Works Director
November 21, 2014
Page 2 of 3
• The concept of the bubble permit for Total Phosphorus between different Permittees has been
pursued in other watersheds within North Carolina. To discuss how this process has been
implemented in other basins, the County should contact Mike Templeton in the NPDES
Permitting Unit at 919-807-6402'.
As identified previously, the renewal permit contains the following significant changes from
your current permit:
• The requirement to begin reporting discharge monitoring data electronically within 270 days of the
NPDES Permit effective date using the NC DWR's Electronic Discharge Monitoring Report (eDMR)
internet application has been added to your final NPDES permit. [See Footnote #1 under Sections A.(1),
A.(2), A.(3), and A.(4) and Special Condition A.(8.)]
For information on eDMR, registering for eDMR and obtaining an eDMR user account, please visit the
following web page: http://portal.ncdenr.org/web/wq/admin/bog/ipu/edmr.
For information on EPA's proposed NPDES Electronic Reporting Rule, please visit the following web
site: http://www2.epa.gov/compliance/proposed-npdes-electronic-reporting-rule.
• Copper and zinc limits in the previous permits were based on demonstrated reasonable potential to
exceed water quality standards in South Carolina. The applicable site -specific copper/zinc standards
were originally developed based on a study by Union County in conjunction with the State of South
Carolina, and based on Water Effect Ratio (WER) calculations. Based on the Reasonable Potential
Analysis for this permit renewal, no reasonable potential was shown for copper and zinc to violate SC
WQS's. In addition, the maximum predicted effluent concentrations for copper and zinc, determined by
the Reasonable Potential Analysis, were both less than fifty percent of their site -specific standards
(permit limitations). In accordance with NC NPDES monitoring guidance, copper and zinc monitoring
was removed from the permit.
• Some of the wording has changed in Special Condition A. (5.), Chronic Toxicity Monitoring, please
review each paragraph carefully.
• Special Condition A. (7.) has been modified to include the specific three years in which the Effluent
Pollutant Scans shall be performed (2016, 2017, and 2018). In addition, at the end of the Special
Condition, 2nd species Toxicity Testing Requirements for municipal permit' renewals per Federal
Regulations [40 CFR 122.21(j)(5)] have been added.
• In accordance with the 2012 Statewide Mercury TMDL mercury effluent data was reviewed. All the
annual averages were less than the Water Quality Based Effluent Limit and the Technology Based
Effluent Limit. The County shall continue to monitor mercury as part of its Effluent Pollutant Scans and
perform a Mercury Minimization Plan (MMP) as described in Special Condition A.(9.). Please note that
the MMP shall be developed within 180 days of the NPDES Permit effective date. A sample MMP was
developed through a stakeholder review process and has been placed on the Division website for
guidance at: http://portal.ncdenr.org/web/wq/swp/ps/npdes
• Instream data confirms that the WWTP effluent is not the cause of the high fecal coliform values in that
segment of the receiving stream. In fact the WWTP effluent appears to dilute the fecal coliform levels
immediately downstream of the WWTP outfall. In accordance with DWR guidance dated 4/22/2002, if
the receiving stream is not impaired for fecal coliform and it is not a Class B waterbody, instream
monitoring for fecal coliform can be removed. Fecal coliform monitoring was removed from the permit's
instream sampling requirements for all three stations.
• NPDES guidance dated 4/22/2002 recommends that conductivity be removed from instream sampling
requirements for 100% domestic wastewater permits. Union County's Twelve Mile Creek WWTP does
not have a pretreatment program and receives no industrial wastewaters. Monitoring for conductivity was
removed from the effluent and instream sampling requirements.
• The Total Phosphorus mass loading limits (Monthly Average = 41.7 lbs/day, Annual Average = 20.85
lbs/day) were capped to ensure no additional TP load, even with expansion to 12.0 MGD. These limits

Mr. Ed Goscicki, Public Works Director
November 21, 2014
Page 3 of 3
were based on a Union County /DWQ/SCDHEC Settlement Agreement for the inclusion of phosphorus
limits to dischargers to the main stem of the Catawba (upstream of Lake Wateree), to comply with the
SC lake standard of 0.06 mg/1. At 12 MGD, the TP mass limits equate to a Monthly Average
concentration of 0.42 mg/1, and an Annual Average concentration of 0.21 mg/1.
• In accordance with DWR guidance for "Exceptionally Performing Facilities" a review of effluent
sampling data from 7/1/2011 through 6/30/2014 confirmed that sampling frequency reductions for
BOD5, TSS, and fecal coliform should be granted. Monitoring for BOD5, TSS, and fecal coliform was
reduced from daily to twice per week in the permit renewal. Ammonia -nitrogen effluent sampling
results did not meet the Guidance requirements to allow for a sampling reduction.
• Upon each expansion, the County shall revert back to daily sampling for BOD5, TSS, and Fecal coliform.
After 6 months of daily sampling, the County can return to twice per week sampling for the parameters
for which no permit limit violation has occurred. See footnote #8 under Sections A.(2, 3, and 4).
If any parts, measurement frequencies or sampling requirements contained in this permit are unacceptable
to you, 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 150B of
the North Carolina General Statutes, and filed with the Office of Administrative Hearings (6714 Mail
Service Center, Raleigh, North Carolina 27699-6714). Unless such demand is made, this decision shall be
final and binding.
Please note that this permit is not transferable except after notice to the Division. The Division may
require modification or revocation and reissuance of the permit. This permit does not affect the legal
requirements to obtain other permits which may be required by the Division of Water Resources or any
other Federal, State, or Local governmental permits that may be required.
If you have any questions concerning this permit, please contact Julie Grzyb by email
([e-mail]) or phone at [phone].
Thomas A. Reeder, Director
elti Division of Water Resources, NCDENR
Enclosure: NPDES Permit NC0085359
cc: NPDES Unit
Central Files
Mooresville Regional Office / Surface Water Protection Section
e-copy:
EPA Region 4
Susan Meadows, Aquatic Toxicity Branch
Jim Struve, P.E., Hazen and Sawyer
Michael Montebello, Manager Domestic Wastewater Permitting Section, SC DHEC
Wayne Harden, SC DHEC

Permit NC0085359
STATE OF NORTH CAROLINA
DEPARTMENT OF ENVIRONMENT AND NATURAL RESOURCES
DIVISION OF WATER RESOURCES
NPDES PERMIT
TO DISCHARGE WASTEWATER UNDER THE
NATIONAL POLLUTANT DISCHARGE ELIMINATION SYSTEM
In compliance with the provision of North Carolina General Statute 143-215.1, other lawful
standards and regulations promulgated and adopted by the North Carolina Environmental
Management Commission, and the Federal Water Pollution Control Act, as amended, the
Union County Public Works Department
is hereby authorized to discharge wastewater from a facility located at the
Twelve Mile Creek Wastewater Treatment Plant
8299 Kensington Drive
Waxhaw, NC
Union County
to receiving waters designated as Twelve Mile Creek in the Catawba River Basin in
accordance with effluent limitations, monitoring requirements, and other conditions set forth in
Parts I, II, III, and IV hereof.
This permit shall become effective January 1, 2015.
This permit and authorization to discharge shall expire at midnight on December 31, 2019.
Signed this day November 21, 2014:
eTTiomas A. Reeder, Director
feit Division of Water Resources
By Authority of the Environmental Management Commission
Page 1 of 17

Permit NC0085359
SUPPLEMENT TO PERMIT COVER SHEET
All previous NPDES Permits issued to this facility, whether for operation or discharge are
hereby revoked, and as of this issuance, any previously issued permit bearing this number is no
longer effective. Therefore, the exclusive authority to operate and discharge from this facility
arises under the permit conditions, requirements, terms, and provisions included herein.
The Union County Public Works Department is hereby authorized to:
1. Continue to operate an existing 6.0 MGD wastewater treatment facility that includes the following
components:
• Influent pump station with stand-by generator
• Self-cleaning influent filter.screening structure and manual bar screen
• Vortex grit chamber
• Four FAO basins (anoxic and oxidation reactors)
• FAO distribution structure
• MLSS distribution structure
• Four final clarifiers
• Four tertiary sand filters
• Two ultraviolet light disinfection systems
• Cascade post aeration
• Sludge thickening facility with a gravity belt thickener and associated polymer storage
and feed system
• Four aerobic digesters with diffused aeration
• Sodium aluminate storage and feed facilities for phosphorus removal
• Odor control facilities
• Main stand-by power generator
This facility is located at the Twelve Mile Creek Wastewater Treatment Plant off Kensington
Drive near Waxhaw in Union County.
2. Upon issuance of an Authorization to Construct (ATC) permit by the Division and submission of
the Engineer's Certification for construction completion, operate a wastewater treatment facility
up to a design flow of 7.5 MGD, and
3. Upon issuance of an Authorization to Construct (ATC) permit by the Division and submission of
the Engineer's Certification for construction completion, operate a wastewater treatment facility
up to a design flow of 9 MGD, and
4. Upon issuance of an Authorization to Construct (ATC) permit by the Division and submission of
the Engineer's Certification for construction completion, operate a wastewater treatment facility
up to a design flow of 12 MGD, and
5. Discharge from said treatment works at the location specified on the attached map into Twelve
Mile Creek, a class C stream in the Catawba River Basin.
Page 2 of 17

Permit NC0085359
PART
A. (1) EFFLUENT LIMITATIONS AND MONITORING REQUIREMENTS — 6 MGD
During the period beginning upon the effective date of this permit and lasting until expansion above 6 MGD or
expiration, the Permittee is authorized to discharge from outfall 001. Such discharge shall be limited and
monitored.' by the Permittee as specified below:
EFFLl7ENT: : --- - Y ,,
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a t
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;LIMITS' : i.'
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:. A0r-4e #
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. r_ _P'rJ
,`41:-e -eney,
...
CLoca o?
Flow
6.0 MGD
Continuous
Recording
I or E
BOD, 5-day, 20°C
(March -October) 3
5.0 mg/L
7.5 mg/L
Twice per Week
Composite
I & E
BOD, 5-day, 20°C
(November — February) 3
10.0 mg/L
15.0 mg/L
Twice per Week
Composite
I & E
Total Suspended Solids 3
30.0 mg/L
45.0 mg/L
Twice per Week
Composite
I & E
NH3 as N
(March — October)
1.0 mg/L
3.0 mg/L
Daily
Composite
E
NH3 as N
(November - February)
2.0 mg/L
6.0 mg/L
Daily
Composite
E
Dissolved Oxygen, mg/L4
Daily
Grab
E
Dissolved Oxygen, mg/L
(June through September)
3NVeek
Grab
U & D
Dissolved Oxygen, mg/L
(October through May)
1/week '
Grab
U & D
pH
> 6.0 and < 9.0 standard units
Daily
Grab
E
Total Nitrogen, mg/L
(NO2+NO3+TKN)
Monthly
Composite
E
Total Phosphorus 5
Monthly Average: 41.70 lbs/day
12 Month Avg.: 20.85 lbs/day
Monthly
Composite
E
Temperature, °C
Daily
Grab
E
Temperature, °C
(June through September)
3/Week
Grab
U & D
Temperature, °C
(October through May)
1/Week
Grab
U & D
Fecal Coliform (geo. mean)
200/100 ml
400/100 ml
Twice per Week
Grab
E
Chronic Toxicity6
Quarterly
Composite
E
Effluent Pollutant Scan7
(Parameter code: NC01)
Monitor and Report •
•
Footnote 7
Footnote 7
E
Footnotes on following page
Page 3 of 17

Permit NC0085359
A. (1) EFFLUENT LIMITATIONS AND MONITORING REQUIREMENTS
[continued]
Footnotes to previous table:
1. No later than 270 days from the effective date of this permit, begin submitting discharge monitoring
reports electronically using NC DWR's eDMR application system. See Special Condition A (8).
2. E=Effluent; I=Influent; U=Upstream; D=Downstream. Upstream: 50 feet upstream from the outfall.
Downstream samples shall be collected at each of two locations, D1 and D2. D1: One quarter mile
downstream from the outfall, before confluence with the first tributary. D2: at NCSR 1301.
Additional downstream dissolved oxygen monitoring is recommended to provide DO stream profile
of Twelve Mile Creek in North Carolina and South Carolina.
3. The monthly average effluent BOD5 and Total Suspended Solids concentrations shall not exceed
15% of the respective influent value (85% removal).
4. The daily average dissolved oxygen effluent concentration shall not be less than 6.0 mg/L.
5. Special condition A (6) describes the methodology for calculation of the monthly average and 12-
month limits.
6. Chronic Toxicity (Ceriodaphnia) P/F @ 90% with testing in February, May, August and November,
refer to A (5).
7. The.permittee shall perform three Effluent Pollutant Scans during the term of this permit.
See Special Condition A (7).
There shall be no discharge of floating solids or foam.
Page 4 of 17

Permit NC0085359
A. (2) EFFLUENT LIMITATIONS AND MONITORING REQUIREMENTS — 7.5 MGD
During the period beginning upon expansion above 6 MGD and lasting until expiration or expansion above 7.5
MGD, the Perrnittee is authorized to discharge from outfall 001. Such discharge shall be limited and monitored.'
•
MONITORING"RE•QUIREMENTV'7'.
•
EFFLUENT :
CHARAQTERISTICS
LIMITS
=7 = ';
- Y
Monthly
=Aveerage -
, Weekly `
#AOOP '°
=
1Daily i
Max
. V.�a
`easMurement
. Frequency ,
' Sample
°• Ik _'
Sample
' 2`'
L� c �ioni,
Flow
7.5 MGD•
Continuous
Recording
I or E
BOD, 5-day, 20°C3
(March- October)
5.0 mg/L
7.5 mg/L
Twice per Week8
Composite
I & E
BOD, 5-day, 20°C 3
(November — February)
10.0 mg/L
15.0 mg/L
Twice per Week8
Composite
I & E
Total Suspended Solids 3
30.0 mg/L
45.0 mg/L
Twice per Week8
Composite
I & E
NH3 as N
(March - October)
1.0 mg/L
3.0 mg/L
Daily
Composite
E
NH3 as N
(November — February)
1.9 mg/L
5.7 mg/L
Daily
Composite
E
Dissolved Oxygen, mg/L4
Daily -
Grab
E
Dissolved Oxygen, mg/L
(June through September)
3/Week
Grab
U & D
Dissolved Oxygen, mg/L
(October through May)
1/Week
Grab
U & D
pH
>
> 6.0 and < 9.0 standard units
Daily
Grab
E
Total Nitrogen, mg/L
(NO2+NO3+TKN)
Monthly
Composite
E
Total Phosphorus 5
Monthly Average: 41.70 lbs/day
Monthly
Composite
E
Temperature, °C
Daily
Grab
E
Temperature, °C
(June through September)
3/Week
Grab
U & D
Temperature, °C
(October through May)
1/Week
Grab
U & D
Fecal Coliform (geo. mean)
200/100 ml
400/100 ml
Twice per Week8
Grab
E
Chronic Toxicity6
Quarterly
Composite
E
Effluent Pollutant Scan7
(Parameter code: NC01)
Monitor and Report
Footnote 7
Footnote 7
E
Footnotes on following page
Page 5 of 17

Permit NC0085359
A. (2) EFFLUENT LIMITATIONS AND MONITORING REQUIREMENTS
[continued]
Footnotes to previous table:
1. No later than 270 days from the effective date of this permit, begin submitting discharge monitoring
reports electronically using NC DWR's eDMR application system. See Special Condition A (8).
2. E=Effluent; I=Influent; U=Upstream; D=Downstream. Upstream: 50 feet upstream from the outfall.
Downstream samples shall be collected at each of two locations, D1 and D2. D1: One quarter mile
downstream from the ouffall, before confluence with the first tributary. D2: at NCSR 1301.
Additional downstream dissolved oxygen monitoring is recommended to provide DO stream profile
of Twelve Mile Creek in North Carolina and South Carolina.
3. The monthly average effluent BOD5 and Total Suspended Solids concentrations shall not exceed
15% of the respective influent value (85% removal).
4. The daily average dissolved oxygen effluent concentration shall not be less than 6.0 mg/L.
5. Special condition A (6) describes the methodology for calculation of the TP monthly average and
12-month limits. At full permitted flow of 12 MGD, TP mass limits equate to 0.42 mg/I (Monthly Avg)
and 0.21 mg/I (Annual Avg).
6. Chronic Toxicity (Ceriodaphnia) P/F @ 90% with testing in February, May, August and November,
refer to A (5). •
7. The permittee shall perform three Effluent Pollutant Scans during the term of this permit.
See Special Condition A (7).
8. Upon expansion above 6 MGD, the County shall revert back to daily sampling of these parameters.
After 6 months of daily sampling, the Permittee may return to twice per week sampling for the
parameters for which no permit limit violation has occurred.
There shall be no discharge of floating solids or foam.
Page 6 of 17

Permit NC0085359
A. (3) EFFLUENT LIMITATIONS AND MONITORING REQUIREMENTS -- 9 MGD
During the period beginning upon 'expansion above 7.5 MGD and lasting until expiration or expansion above 9 MGD, the Permittee is authorized to discharge from outfall 001. Such discharge shall be limited and monitored1
by the Permittee as specified below:
EFFLUENT
CHARACTERISTICS
LIMITS
.......•. .. _
MONITORING REQUIREMEN_ TS
�S1sC.9 P• I% 5 : b "-'" iY ia7r` ♦'fl i . •..cL+.Lci
Monthly
ve age
Weekly
Average
Daily
Mxa
Measurement
_; Frequency
:Sample ,'
T e
7 .`Sample
� tLo 23
Flow
9.0 MGD
Continuous
Recording
I or E
BOD, 5-day, 20°C
(March- October) 3
5.0 mg/L
7.5 mg/L
Twice per Week8
Composite
•
I & E
BOD, 5-day, 20°C 3
(November — February)
10.0 mg/L
15.0 mg/L
•
Twice per Week8
Composite
I & E
Total Suspended Solids 3
30.0 mg/L
45.0 mg/L
Twice per Week8
Composite
I & E
NH3 as N
(March - October)
1.0 mg/L
3.0 mg/L
Daily
Composite
E
NH3 as N
(November —February)
.1.9 mg/L
5.7 mg/L
Daily
Composite
E
Dissolved Oxygen, mg/L4
Daily
Grab
E
Dissolved Oxygen, mg/L
(June through September)
• •
3/Week
Grab
U & D
Dissolved Oxygen, mg/L
(October through May)
.
1/Week
Grab
U & D
pH
> 6.0 and < 9.0 standard units
Daily
Grab
E
Total Nitrogen, mg/L
(NO2+NO3+TKN) •
Monthly
Composite
E
Total Phosphorus 5
Monthly Average: 41.70 lbs/day
12 Month Avg.: 20.85 lbs/day
Monthly
Composite
E
Temperature, °C .
Daily
Grab
E •
Temperature, °C
(June through September)
3/Week
Grab
U & D
Temperature, °C
(October through May)
1/Week
Grab
U & D
Fecal Colifprm (geo. mean)
200/100 ml
400/100 ml
Twice per Week8
Grab
E
Chronic Toxicity6
Quarterly
Composite
E
Effluent Pollutant Scan7
(Parameter code: NC01)
Monitor and Report
Footnote 7
Footnote 7
E
Footnotes on following page
Page 7 of 17

Permit NC0085359
A. (3) EFFLUENT LIMITATIONS AND MONITORING REQUIREMENTS
[continued]
Footnotes to previous table:
1. No later than 270 days from the effective date of this permit, begin submitting discharge monitoring
reports electronically using NC DWR's eDMR application system. See Special Condition A (8).
2. E=Effluent; I=Influent; U=Upstream; D=Downstream. Upstream: 50 feet upstream from the outfall.
Downstream samples shall be collected at each of two locations, D1 and D2. D1: One quarter mile
downstream from the outfall, before confluence with the first tributary. D2: at NCSR 1301.
Additional downstream dissolved oxygen monitoring is recommended to provide DO stream profile
of Twelve Mile Creek in North Carolina and South Carolina.
3. The monthly average effluent BOD5 and Total Suspended Solids concentrations shall not exceed
15% of the respective influent value (85% removal).
4. The daily average dissolved oxygen effluent concentration shall not be less than 6.0 mg/L.
5. Special condition A (6) describes the methodology for calculation of the TP monthly average and
12-month limits. At full permitted flow of 12 MGD, TP mass limits equate to 0.42 mg/I (Monthly Avg)
and 0.21 mg/I (Annual Avg).
6. Chronic Toxicity (Ceriodaphnia) P/F @ 90% with testing in February, May, August and November,
refer to A (5).
7. The permittee shall perform three Effluent Pollutant Scans during the term of this permit.
See Special Condition A (7).
8. Upon expansion above 7.5 MGD, the County shall revert back to daily sampling of these
parameters. After 6 months of daily sampling, the Permittee may return to twice per week sampling
for the parameters for which no permit limit violation has occurred.
There shall be no discharge of floating solids or foam.
Page 8 of 17

Permit NC0085359
A. (4) EFFLUENT LIMITATIONS AND MONITORING REQUIREMENTS —12 MGD
During the period beginning upon expansion above 9 MGD and lasting until expiration, the Permittee is
authorized to discharge from ouffall 001. Such discharge shall be limited and monitored by the Permittee as
specified below:
EFFLUENT !
CIHAR�eTERISJTICS
1� 1 1 �!f- .'y.i�� d
� �, � :• ...'•
LIMITS'.'.,
a 4
� �i ..
MONITORINGREQUIREMENTS
•y . ,,
�S3ww'i+.. �-+}�xa:�wL`Y�. � •• ".$ti� ! .2"� � , C � ;
.::y �1
.,
..
.:lMflon_thl .y
; ,Week yf '7
Avgerage.
1:�:i.. s.�r .�.. 1
, 'Daily• ?
i ax-.•
k ......,.r •T •, -
{ ;LMeasurementi.: F
, S�am,Ple' i
T_yj c.
' .,Sample
A age :
.ls 3
;Frequency
.... r 'Z. 1
r _•."-oca ion2
Flow
12.0 MGD
Continuous
Recording
I or E
BOD, 5-day, 20°C
(March - October) 3
5.0 mg/L
7.5 mg/L
Twice per Week8
Composite
I & E
BOD, 5-day, 20°C
(November - February) 3
10.0 mg/L
g
15.0 mg/L
g
Twice per Week 8
Composite
p
I & E
Total Suspended Solids3
30.0 mg/L
45.0 mg/L
Twice per Week8
Composite
I & E
NH3 as N
(March — October 31) •
1.0 mg/L
3.0 mg/L
Daily
Composite
E
NH3 as N
(November — February)
1.9 mg/L
5.7 mg/L
Daily
Composite
E
Dissolved Oxygen, mg/L4
Daily
Grab
E
Dissolved Oxygen, mg/L
(June through September)
3/Week
Grab
U & D
Dissolved Oxygen, mg/L
(October through May)•
1/Week
Grab
U & D
pH •
> 6.0 and < 9.0 standard units
Daily •
Grab
E
Total Nitrogen, mg/L
(NO2+NO3+TKN)
Monthly
Composite
p
E
Total Phosphorus5
Monthly Average: 41.70 Ibs/day
12 Month Avg.: 20.85 Ibs/day
Monthly
Composite
E
Temperature, °C
Daily
Grab
E
Temperature, °C
(June through September)
3/Week
Grab
U & D
Temperature, °C
(October through May)
•
1NVeek
Grab
U & D
Fecal Coliform (geo. mean)
200/100 ml
400/100 ml
Twice per Week8
Grab
E
Chronic Toxicity6
Quarterly
Composite
E
Effluent Pollutant Scan7
(Parameter code: NC01)
Monitor and Report
Footnote 7
Footnote 7
E
Footnotes on following page
Page 9 of 17

Permit NC0085359
A. (4) EFFLUENT LIMITATIONS AND MONITORING. REQUIREMENTS
[continued]
Footnotes to previous table:
1. No later than 270 days from the effective date of this permit, begin submitting discharge monitoring
reports electronically using NC DWR's eDMR application system. See Special Condition A (8).
2. E=Effluent; I=Influent; U=Upstream; D=Downstream. Upstream: 50 feet upstream from the outfall.
Downstream samples shall be collected at each of two locations, D1 and D2. D1: One quarter mile
downstream from the outfall, before confluence with the first tributary. D2: at NCSR 1301.
Additional downstream dissolved oxygen monitoring is recommended to provide DO stream profile
• of Twelve Mile Creek in North Carolina and South. Carolina.
3. The monthly average effluent BOD5 and Total Suspended Solids concentrations shall not exceed
15% of the respective influent value (85% removal).
4. The daily average dissolved oxygen effluent concentration shall not be Tess than 6.0 mg/L.
5. Special condition A (6) describes the methodology for calculation of the TP monthly average and
12-month limits. At full permitted flow of 12 MGD, TP mass limits equate to 0.42 mg/I (Monthly Avg)
and 0.21 mg/I (Annual Avg).
6. Chronic Toxicity (Ceriodaphnia) P/F @ 90% with testing in February, May, August and November,
refer to A (5).
7. The permittee shall perform three Effluent Pollutant Scans during the term of this permit.
See Special Condition A (7).
8. Upon expansion above 9 MGD, the County shall revert back to daily sampling of these parameters.
After 6 months of daily sampling, the Permittee may return to twice per week sampling for the
parameters for which no permit limit violation has occurred.
There shall be no discharge of floating solids or foam.
Page 10 of 17

Permit NC0085359
A. (5) CHRONIC TOXICITY PASS/FAIL PERMIT LIMIT — FOR 6.0, 7.5, 9.0, AND 12.0 MGD
The effluent discharge shall at no time exhibit observable inhibition of reproduction or significant mortality to
Ceriodaphnia dubia at an effluent concentration of 90 %.
The permit holder shall perform at a minimum, quarterly monitoring using test procedures outlined in the "North
Carolina Ceriodaphnia Chronic Effluent Bioassay Procedure," Revised December 2010, or subsequent versions
or "North Carolina Phase II Chronic Whole Effluent Toxicity Test Procedure" (Revised- December 2010) or
subsequent versions. The tests will be performed during the months of February, May, August, and November.
These months signify the first month of each three-month toxicity testing quarter assigned to the facility. Effluent
sampling for this testing must be obtained during representative effluent discharge and shall be performed at the
NPDES permitted final effluent discharge below all treatment processes.
If the test procedure performed as the first test of any single quarter results in a failure or ChV below the
permit limit, then multiple -concentration testing.shall be performed at a minimum, in each of the two
following months as described in "North Carolina Phase II Chronic Whole Effluent Toxicity Test
Procedure" (Revised -December 2010) or subsequent versions.
The chronic value for multiple concentration tests will be determined using the geometric mean of the highest
concentration having no detectable impairment of.reproduction or survival and the lowest concentration that does
have a detectable impairment of reproduction or survival. The definition of "detectable impairment," collection
methods, exposure regimes, and further statistical methods are specified in the "North Carolina Phase II Chronic
Whole Effluent Toxicity Test Procedure" (Revised -February 1998) or subsequent versions.
All toxicity testing results required as part of this permit condition will be entered on the Effluent Discharge
Monitoring Form (MR-1) for the months in which tests were performed, using the parameter code TGP3B for the
pass/fail results and THP3B for the Chronic Value. Additionally, DWR Form AT-3 (original) is to be sent to the
following address:
Attention: North Carolina Division of Water Resources
Water Sciences Section/Aquatic Toxicology Branch
1621 Mail Service Center
Raleigh, North Carolina 27699-1621
Completed Aquatic Toxicity Test Forms shall be filed with the Water Sciences Section no later than 30 days after •
the end of the reporting period for which the report is made.
Test data shall be complete, accurate, include all supporting chemical/physical measurements and all
concentration/response data, and be certified by laboratory supervisor and ORC or approved designate signature.
Total residual chlorine of the effluent toxicity sample must be measured and reported if chlorine is employed for
disinfection of the waste stream.
Should there be no discharge of flow from the facility during a month in which toxicity monitoring is required, the
permittee will complete the information located at the top of the aquatic toxicity (AT) test form indicating the facility
name, permit number, pipe number, county, and the month/year of the report with the notation of "No Flow" in the
comment area of the form. The report shall be submitted to the Water Sciences Section at the address cited
above.
Should the permittee fail to monitor during a month in which toxicity monitoring is required, monitoring will be
required during the following month. Assessment of toxicity compliance is based on the toxicity testing quarter,
which is the three month time interval that begins on the first day of the month in which toxicity testing is required
by this permit and continues until the final day of the third month.
Should any test data from this monitoring requirement or tests performed by the North Carolina Division of Water
Resources 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, minimum control organism reproduction, and appropriate environmental controls, shall constitute an
invalid test and will require immediate follow-up testing to be completed no later than the last day of the month
following the month of the initial monitoring.
Page 11 of 17

Permit NC0085359
A. (6) TOTAL PHOSPHORUS (TP) MONITORING
The Permittee shall calculate a 12-month rolling average mass loading as the sum of monthly loadings, according
to the following equations:
(1) Monthly Average (pounds/day) = TP x Qw x 8.34
Where:
TP = the arithmetic average of total phosphorus concentrations (mg/L) obtained via composite samples
(either daily, weekly, or monthly average values) collected during the month
Qw = the average daily waste flow (MGD) for the month
8.34= conversion factor, from (mg/L x MGD) to pounds
The 12-month rolling average mass loading is defined as the sum of the monthly average loadings for the
previous 12 months inclusive of the reporting month:
12
(2) 12-Month Average Mass Loading (poundslday)= ETPma :-12 (inclusive of reporting month)
1
Where:
TPma is defined as the total phosphorus monthly average mass loading (calculated above).
The monthly average and 12-month average mass loadings shall be reported on the attached worksheet [see
next page] and submitted with the Discharge Monitoring Report (DMR) for Twelve Mile Creek WWTP.
The Permittee shall report the TP concentration for each sample on the appropriate DMR. Reporting of and
compliance with the TP limit shall be done on a monthly basis.
• Page 12 of 17

Permit NC0085359
Reporting Month:
Beginning Month:
Ending Month:
Union County
Twelve Mile Creek WWTP
Nutrient Worksheet
NPDES Permit NC0085359
(Month 1)
(Month 12)
Monthly Average Total Phosphorus
pounds/day
Month 1
Month 2
.
Month 3
Month 4
Month 5
Month 6
Month 7
Month 8
Month 9
Month 10
Month 11
Month 12
12-Month Mass Average
Loading
Note: The TP mass loadings for the current reporting month should be entered for Month 1.
Page 13 of 17

Permit NC0085359
A. (7) EFFLUENT POLLUTANT SCAN
The Permittee shall perform a total of three (3) Effluent Pollutant Scans for all parameters listed below. One scan
must be performed in each of the following years: 2016, 2017, and 2018. Analytical methods shall be in accordance
with 40 CFR Part 136 and shall be sufficiently sensitive to determine whether parameters are present in
concentrations greater than applicable standards and criteria. Samples should be collected with one quarterly
toxicity test each year, and must represent seasonal variation [i.e., do not sample in the same quarter every year].
Unless otherwise indicated, metals shall be analyzed as "total recoverable."
Ammonia (as N)
Chlorine (total residual, TRC)
Dissolved oxygen
Nitrate/Nitrite
Kjeldahl nitrogen
Oil and grease
Phosphorus
Total dissolved solids
Hardness
Antimony
Arsenic
Beryllium
Cadmium
Chromium
Copper
Lead
Mercury (EPA Method 1631E)
Nickel
Selenium
Silver
Thallium
Zinc
Cyanide
Total phenolic compounds
Volatile organic compounds:
Acrolein
Acrylonitrile
Benzene
Bromoform
Carbon tetrachloride
Chlorobenzene
Chlorodibromomethane
Chloroethane
2-chloroethylvinyl ether
Chloroform
Dichlorobromomethane
1,1-dichloroethane
1,2-dichloroethane
Trans-1,2-dichloroethylene
1,1-dichloroethylene
1,2-dichloropropane
1,3-dichloropropylene
Ethylbenzene
Methyl bromide
Methyl chloride
Methylene chloride
1,1,2,2-tetrachloroethane
Tetrachloroethylene
Toluene
1,1,1-trichloroethane
1,1,2-trichloroethane
Trichloroethylene
Vinyl chloride
Acid -extractable compounds:
P-chloro-m-cresol
2-chlorophenol
2,4-dichlorophenol
2,4-dimethylphenol
4,6-dinitro-o-cresol
2,4-dinitrophenol
2-nitrophenol
4-nitrophenol
Pentachlorophenol
Phenol
2,4,6-trichlorophenol
Base -neutral compounds:
Acenaphthene
Acenaphthylene
Anthracene
Benzidine
Benzo(a)anthracene
Benzo(a)pyrene
3,4 benzofluoranthene
Benzo(ghi)perylene
Benzo(k)fluoranthene
Bis (2-chloroethoxy) methane
Bis (2-chloroethyl) ether
Bis (2-chloroisopropyl) ether
Bis (2-ethylhexyl) phthalate
4-bromophenyl phenyl ether
Butyl benzyl phthalate
2-chloronaphthalene
4-chlorophenyl phenyl ether
Chrysene
Di-n-butyl phthalate
Di-n-octyl phthalate
Dibenzo(a, h)anth racene
1,2-dichlorobenzene
1,3-dichlorobenzene
1,4-dichlorobenzene
3,3-dichlorobenzidine
Diethyl phthalate
Dimethyl phthalate
2,4-dinitrotoluene
2,6-dinitrotoluene
1,2-diphenylhydrazine
Fluoranthene
Fluorene
Hexachlorobenzene
Hexachlorobutadiene
Hexachlorocyclo-pentadiene
Hexachloroethane
ndeno(1, 2,3-cd)pyrene
Isophorone
Naphthalene
Nitrobenzene
N-nitrosodi-n-propylamine
N-nitrosodimethylamine
N-nitrosodiphenylamine
Phenanthrene
Pyrene
1,2,4-tichlorobenzene
Reporting. Test results shall be reported on DWQ Form -A MR-PPA1 (or in a form approved by the Director) by
December 31st of each designated sampling year. The report shall be submitted to the following address: NC
DENR / DWR / Central Files, 1617 Mail Service Center, Raleigh, North Carolina 27699-1617.
Page 14 of 17

Permit NC0085359
Additional Toxicity Testing Requirements for Municipal Permit Renewal. Please note that Municipal facilities
that are subject to the Effluent Pollutant Scan requirements listed above are also subject to additional toxicity
testing requirements specified in Federal Regulation 40 CFR 122.21(j)(5). The US EPA requires four (4) toxicity
tests for a test organism other than the test species currently required in this permit. The multiple species tests
should be conducted either quarterly for a 12-month period prior to submittal of the permit renewal application, or
four tests performed at leastannually in the four and one half year period prior to the application. These tests
shall be performed for acute or chronic toxicity, whichever is specified in this permit. The multiple species toxicity
test results shall be filed with the Aquatic Toxicology Branch at the following address:
North Carolina Division of Water Resources
Water Sciences Section/Aquatic Toxicology Branch
1621 Mail Service Center
Raleigh, North Carolina 27699-1621
Contact the Division's Aquatic Toxicology Branch at 919-743-8401 for guidance on conducting the additional
toxicity tests and reporting requirements. Results should also be summarized in Part E (Toxicity Testing Data) of
EPA Municipal Application Form 2A, when submitting the permit renewal application to the NPDES Permitting
Unit.
Page 15 of 17

Permit NC0085359
A. (8) ELECTRONIC REPORTING OF DISCHARGE MONITORING REPORTS
Proposed federal regulations require electronic submittal of all discharge monitoring reports (DMRs) and specify
that, if a state does not establish a system to receive such submittals, then permittees must submit DMRs
electronically to the Environmental Protection Agency (EPA). The Division anticipates that these regulations will
be adopted and is beginning implementation in late 2013.
NOTE: This special condition supplements or supersedes the following sections within Part II of this permit
(Standard Conditions for NPDES Permits):
• Section B. (11.)
• Section D. (2.)
• Section D. (6.)
• Section E. (5.)
Signatory Requirements
Reporting
Records Retention
Monitoring Reports
1. • Reporting [Supersedes Section D. (2.) and Section E. (5.) (a)1
Beginning no later than 270 days from the effective date of this permit, the permittee shall begin reporting
discharge monitoring data electronically using the NC DWR's Electronic Discharge Monitoring Report (eDMR)
internet application.
Monitoring results obtained during the previous month(s) shall be summarized for each month and submitted
electronically using eDMR. The eDMR system allows permitted facilities to enter monitoring data and submit
DMRs electronically using the internet. Until such time that the state's eDMR application is compliant with
EPA's Cross -Media Electronic Reporting Regulation (CROMERR), permittees will be required to submit all
discharge monitoring data to the state electronically using eDMR and will be required to complete the eDMR
submission by printing, signing, and submitting one signed original and a copy of the computer printed eDMR
to the following address:
NC DENR / DWR / Information Processing Unit
ATTENTION: Central Files / eDMR
1617 Mail Service Center
Raleigh, North Carolina 27699-1617
If a permittee is unable to use the eDMR system due to a demonstrated hardship or due to the facility being
physically located in an area where less than 10 percent of the households have broadband access, then a
temporary waiver from the NPDES electronic reporting requirements may be granted and discharge
monitoring data may be submitted on paper DMR forms (MR 1, 1.1, 2, 3) or alternative forms approved by the
Director. Duplicate signed copies shall be submitted to the mailing address above.
Requests for temporary waivers from the NPDES electronic reporting requirements must be submitted in
writing to the Division for written approval at least sixty (60) days prior to the date the facility would be
required under this permit to begin using eDMR. Temporary waivers shall be valid for twelve (12) months and
shall thereupon expire. At such time, DMRs shall be submitted electronically to the Division unless the
permittee re -applies for and is granted a new temporary waiver by the Division.
Information on eDMR and application for a temporary waiver from the NPDES electronic reporting
requirements is found on the following web page:
http:/lportal.ncdenr.org/web/wo/admin/bog/ipu/edmr
Regardless of the submission method, the first DMR is due on the last day of the month following the
issuance of the permit or in the case of a new facility, on the last day of the month following the
commencement of discharge.
Page 16 of 17

Permit NC0085359
2. Signatory Requirements 'Supplements Section B. (11.) (b) and supersedes Section B. (11.) (d)1
All eDMRs submitted to the permit issuing authority shall be signed by a person described in Part II, Section
B. (11.)(a) or by a duly authorized representative of that person as described in Part II, Section B. (11.)(b). A
person, and not a position, must be delegated signatory authority for eDMR reporting purposes.
For eDMR submissions, the person signing and submitting the DMR must obtain an eDMR user account and
login credentials to access the eDMR system. For more information on North Carolina's eDMR system,
registering for eDMR and obtaining an eDMR user account, please visit the following web page:
http://portal.ncdenr.org/web/wq/admin/boq/ipu/edmr
Certification. Any person submitting an electronic DMR using the state's eDMR system shall make the
following certification [40 CFR 122.22]. NO OTHER STATEMENTS OF CERTIFICATION WILL BE
ACCEPTED:
"I certify, under penalty of law, that this document and all attachments were prepared under my direction or
supervision in accordance with a system designed to assure that qualified personnel properly, gather and
evaluate the information submitted. Based on my inquiry of the person or persons who manage the system, or
those persons directly. responsible for gathering the information, the information submitted is, to the best of
my knowledge and belief, true, accurate, and complete. l am aware that there are significant penalties for
submitting false information, including the possibility of fines and imprisonment for knowing violations."
3. Records Retention [Supplements Section D. (6.)1
The permittee shall retain records of all Discharge Monitoring Reports, including eDMR submissions. These
records or copies shall be maintained for a period of at least 3 years from the date of the report. This period
may be extended by request of the Director at any time [40 CFR 122.41].
A. (9) Mercury Minimization Plan (MMP)
The permittee shall develop and implement a mercury minimization plan during this permit term. The MMP shall
be developed within 180 days of the NPDES Permit Effective Date, and shall be available for inspection on -site.
A sample MMP was developed through a stakeholder review process and has been placed on the Division .
website for guidance (http://portal.ncdenr.org/web/wq/swp/ps/npdes, under Model Mercury Minimization Plan).
The MMP should place emphasis on identification of mercury contributors arid goals for reduction. Results shall
be summarized and submitted with the next permit renewal.
Page 17 of 17

Twelve Mile Creek
WWTP
Outfall 001
Facility Information
Latitude: 34°57'01" Sub -Basin: 03-08-38
Longitude: 80°45'44" 8-Digit HUC 03050103
Quad #: H15NE
Stream Class: C
Receiving Stream: Twelve Mile Creek NOT TO SCALE
Permitted Flow: 6.0 and 12.0 MGD
Facility
Location
IS",
Twelve Mile Creek WWTP
NC0085359
Union County

Supporting Material
Fact Sheet
NC0085359
NCDENR/DWR
FACT SHEET FOR NPDES PERMIT DEVELOPMENT
NPDES Permit NC0085359
Applicant/Facility Name:
Applicant Address:
Facility Address:
Permitted Flow
Type of Waste:
Facility/Permit Status:
Facility Classification
County:
Facility Information
Union County Public Works/ Twelve Mile Creek WWTP
500 North Main Street, Suite 500 Monroe, N.C. 28112-4730
8299 Kensington Drive Waxhaw, NC 28173
Existing: 6.0 MGD/Proposed Phased Expansion: 9&12 MGD
100% Domestic/No Pretreatment Program
Renewal + Expansion
IV
Union
Miscellaneous
Receiving Stream:
Twelve Mile
Creek
Regional Office:
Mooresville
Stream Classification:
303(d) Listed?
Subbasin:
C
Yes- see text
03-08-38
Catawba Basin
USGS Topo Quad:
Permit Writer:
Date:
H15NE/Catawba NE
Julie Grzyb
September 15, 2014
Amended: 11/14/14
Drainage Area (mi2):
Summer 7Q10 (cfs)
Winter 7Q10 (cfs):
Average Flow (cfs):
IWC (%):
76.8
0.1
1.5
72.7
99%
8-digit HUC:
03050103
Location:
41111,
A.Summary- Renewal + Expansion
Union County is requesting renewal + expansion of its NPDES permit for Twelve Mile Creek WWTP.
The current permit provides for a wastewater discharge of up to 6 MGD, and the Permittee is requesting a
future phased expansion to 9 and 12 MGD. Influent is 100% domestic and serves the Towns of Waxhaw
and Weddington, along with other portions of Union County for a total of approximately 58,000 people.
There are no SIUs or CIUs discharging to the system, and thus no Pretreatment program. Current permit
limits for 6 MGD reflect advanced treatment requirements of BOD = 5 mg/1, NH3-N = 1 mg/1, and mass
total phosphorus (TP) limitations. The Permittee originally submitted a request for Major Modification
for ultimate expansion to 12 MGD dated February 11, 2014. This was supplemented with additional
information dated April 22, 2014, to enable the Division to process both a renewal and expansion
together. The current permit does not expire until June 30, 2015.
B. Receiving Stream
This facility discharges to Twelve Mile Creek within the Catawba River Basin. From its source to the
NC/SC State Line, the creek is classified as C waters. Waters with this classification have a best usage
for aquatic life propagation and maintenance of biological integrity, wildlife, secondary recreation and
agriculture. Stream flow information was updated in 2002 by the United States Geological Survey
(USGS) for a nearby gaging station at Highway 16 just 2500 ft upstream of the Twelve Mile Creek
WWTP discharge point. This data indicates a very low summer flow with summer 7Q10 flow = 0.1 cfs.
From the discharge point, Twelve Mile Creek flows for approximately 2 miles prior to crossing the
NC/SC State line, and ultimately discharges into the Catawba River approximately 15 miles below the
outfall.
Page 1 of 8

Supporting Material
Fact Sheet
NC0085359
Twelve Mile Creek is listed on the Draft 2014 303(d) list as impaired for Fish Community (Fair Rating).
This rating is based on a sample station (C9819500) located upstream of the outfall, near Waxhaw at
NC16 crossing. On the Final 2012 303(d) list, this station was also listed as impaired for copper, turbidity,
and low dissolved oxygen (DO). The removal of impairment status for turbidity and dissolved oxygen
from the Draft 2014 list was based on assessment and interpretation of more recent or more accurate data
in the record demonstrating the parameters of interest are meeting criteria. The removal of copper
impairment was based on a change in Assessment Methods per NC Environmental Management
Commission in 2013.
Historically, low DO values have been reported on occasions in Twelve Mile Creek, both upstream and
downstream of the discharge. During the extreme drought conditions of Summer 2007, DO values below
5.0 mg/1 were reported during 41 sample events at Upstream Station 1 (50-feet above discharge),
compared to only 10-11 values below 5.0 mg/1 at Downstream Stations D1 (1/4 mile below discharge)
and D2 (1 mile below discharge). Union County also conducted an intensive DO survey during Summer
2009 to evaluate instream DO trends. This data indicates that low DO conditions are much more
prevalent in the upstream stations in Twelve Mile Creek and its tributaries. Based on 36 sample events,
there were 8 values reported below 5.0 mg/1 at Downstream Station D1, compared to more than 20 values
below 5.0 mg/1 at various upstream stations.
In conclusion, Twelve Mile Creek is not currently listed as impaired for DO on the Draft 2014 303(d) list,
and various instream sampling efforts indicate that occasional summer low DO conditions are naturally
occurring and are much more prevalent in the upper reaches of Twelve Mile Creek and its tributaries. A
primary conclusion of the County 2009 Summer D.O. study was that during low flow conditions, debris.
dams and other obstructions in several locations can slow stream velocity, thus decreasing reaeration
rates.
C. Current Effluent Characteristics
1. Flow. The WWTP's average flow was 3.29 MGD during calendar year 2013, which represents
55% of permitted flow. Monthly Average flows ranged from 2.98 MGD to 3.58 MGD.
2. Table I. lists some average and maximum effluent data collected from 1/2011 through 3/2014.
Table I.
Parameter
Flow
BOD5
Total
Suspended
Solids
Ammonia
Nitrogen
Total
Nitrogen
Total
Phosphorus
Monthly Avg.
Total
Copper
Total
Zinc
(MGD)
(mg/1)
(mg/L)
(mg/L)
(mg/L)
(lb/day)
(µg/L)
(µg/L)
average
3.47
2.82
5.69
0.93
9.15
7.93
5.08
52
maximum
8.4
31.5
116
6.3
17.9
46.99
10.90
70
Limit (MA)
5 S/10 W
30
1 S/2 W
41.70
13.2
175
D. Evaluation of Compliance Data
1. DMRs have been reviewed for the period January 2011 through May 2014. The following
violations have been cited: TP in 12/2013 (Annual load exceeded); Ammonia -nitrogen in 9/2012
(Monthly and weekly average exceeded) and 1/2014 (Monthly avg. exceeded); BOD5 in 4/2014
(Monthly and Weekly average exceeded) and 5/2014 (weekly average exceeded).
2. The last routine compliance evaluation inspection was conducted on June 29, 2012 and the
facility evaluation rating was very reliable. On February 4, 2014 a bioassay compliance test was
performed. Bioassay samples were collected and split between the DWR laboratory and the
facility's lab, Pace Analytical. Both chronic tests using Ceriodaphnia resulted in a pass.
Page 2 of 8

Supporting Material
Fact Sheet
NC0085359
3. Toxicity Testing. The facility has passed 23 of 23 chronic 7-day ceriodaphnia dubia toxicity tests
at 90% effluent concentration for the period 2009-2014. The facility has also passed 2nd species
toxicity testing using fathead minnow.
E. Evaluation of Instream Data
DMR files for upstream and downstream data were reviewed from May 2012 through April 2014.
As stated above, Union County performs instream monitoring at one station upstream and two
downstream stations below the plant outfall. Samples are collected for temperature, dissolved oxygen,
fecal coliform, and conductivity at each of the stations. See the attached Table II to review instream
sampling results.
• As discussed in Section B, the data indicates that the low instream DO is attributable to natural
conditions upstream. Thirty-seven samples taken upstream showed DO values below the minimum
instantaneous Water Quality Standard value of 4 mg/L. Correspondingly, 36 samples were measured
below the minimum instantaneous Water Quality Standard value of 4 mg/L at downstream stations DI
and DII.
• Out of 173 instream samples, temperature remained constant up and downstream 75% of the time and
in no case did the change in temperature increase greater than 2.8 degrees C°.
• Fecal coliform samples were markedly high in the upstream and D2 downstream stations. In 2013,
71% of the fecal coliform samples in July and 58% in June were greater than 400/100m1 at the
upstream station. The DII downstream station had a corresponding 71% of the non-consecutive
samples taken in July greater than 400/100m1 and 67% in June. Downstream station DI below the
WWTP outfall had slightly less values greater than 400/100m1 with 57% of the fecal coliform non-
consecutive samples exceeding the 400/100m1 in July and 50% in June. No effluent violations for any
parameters were noted during this time period. While many fecal coliform exceedances have been
detected (not standards violations), the 5 year geometric mean is 243. Twelve -mile creek is currently
assessed in 3a for fecal coliform. Instream data confirms that the WWTP effluent is not the cause of
the high fecal coliform values and in fact, the WWTP effluent appears to dilute the fecal coliform
levels in the stream. It is recommended that fecal coliform monitoring be removed from the instream
- __sampling requirement for all three instream stations.
• eOildtietiNtils a parameter better suited for measuring the impact of inorganic wastes. Most of the
conductivity vafues were 200 µmhos/cm or less. Union County's Twelve Mile Creek WWTP does
not have a pretreatment program and receives no industrial wastewaters. NPDES guidance
recommends that conductivity be removed from instream sampling requirements for 100% domestic
wastewater permits. It is recommended that conductivity monitoring be removed from the effluent
and instream sampling requirements.
F. Reasonable Potential (RP) Analysis
Effluent sampling data from 4 effluent pollutant scans for As, Be, Cd, Cr, CN, Pb, Ni, Se, and Ag showed
all parameters less than detection levels.
Reasonable potential analyses were conducted for Cu and Zn_(see RPA attached). Effluent sampling data
from May 2013 to June 2014, for Copper and Zinc, showed no reasonable potential to violate permit
limitations. The existing permit limitations are based on a WER study performed in 2005/2006 which
determined that a Cu limitation of 12.9 µg/L and a Zn limitation of 171 µg/L would-be sufficient to
protect SC water quality standards. Since no reasonable potential was shown to violate permit limitations
and the maximum predicted concentrations for Cu and Zn at a 95% probability and a 95% confidence
level were both less than half the water quality based permit limit, monitoring for both parameters was
removed from the permit.
It should be noted that the consultant for Union County submitted recalculations on the 2005/2006 WER
study using methods outlined in EPA's Streamlined Water -Effect Ratio Procedure for Discharges of
Copper (EPA-822-R-01-005). The recalculations using EPA methods determined a chronic permit
Page 3 of 8

Supporting Material
Fact Sheet
NC0085359
limitation of 20.4 for Cu and 273.7 for Zn. Additional information has been requested from the
consultant and will be reviewed in the future; however, since the more stringent limitations determined in
the original calculations are being achieved and no reasonable potential was shown to violate the more
stringent numbers, DWR did not believe it was necessary to complete the recalculation review for
issuance of this permit.
G. Mercury TMDL Evaluation
A mercury TMDL was approved by US EPA in October 2012 and will be implemented in the final
permit. Table II summaries the available mercury data used to determine mercury TMDL requirements:
Table III.
Mercury Data Statistics (Method 1631E)
2013
2014
2011
# of Samples
1
1
1
Annual Average, ng/L
2.2
1.3
0.5
Maximum Value, ng/L
2.16
1.27
0.54
TBEL, ng/L
47
WQBEL, ng/L
12.1
Mercury was not sampled in 2012
Per mercury TMDL guidance, if mercury samples do not exceed the Technology Based Effluent Limit or
the Water Quality Based Effluent Limit, as in this case, then mercury monitoring (Method 1631E)
conducted in the 3 required PPAs will be sufficient. In addition, since there are multiple mercury
measurements above 1 ng/L, and this is a major municipal facility with a permitted flow greater than 2.0
MGD, a special condition A. (8) requiring the facility to develop a mercury minimization plan will be
added.
H. Basis for Permit Effluent Limits
1. Copper/Zinc. Copper and zinc limits in the previous permits were based on demonstrated RP to
exceed water quality standards in South Carolina. The applicable site -specific copper/zinc
standards were originally developed based on a study by Union County in conjunction with the
State of South Carolina, and based on Water Effect Ratio (WER) calculations. Based on the RPA
for this permit renewal, no reasonable potential was shown to violate SC WQS's so copper and
zinc monitoring was removed from the permit.
2. Total Phosphorus (TP). The permit renewal and the existing permit contain total phosphorus
mass -based limits. The mass loading limits (Monthly Average = 41.7 lbs/day, Annual Average =
20.85 lbs/day) were capped to ensure no additional TP load, even with expansion to 12.0 MGD.
These limits were based on a Union County /DWQ/SCDHEC Settlement Agreement for the
inclusion of phosphorus limits to dischargers to the main stem of the Catawba (upstream of Lake
Wateree), to comply with the SC lake -standard -of 0.06 mg/1. At 12 MGD, the TP mass limits
equate to a Monthly Average concentration of 0.42 mg/1, and an Annual Average concentration of
0.21 mg/1.
3. Seasonal Limits for BOD and NH3-N. In order to comply with SC water quality standards and
their 0.1 mg/1 D.O. Rule, seasonal limits were set to Summer defined as March -October and
Winter defined as November -February.
4. The facility has no Pretreatment program and does not receive industrial wastewaters. Effluent,
upstream and downstream monitoring for conductivity was removed from the permit. Instream
sampling below the WWTP effluent showed less fecal coliform exceedances then the
corresponding samples taken upstream and further downstream at station DII. The WWTP does
not appear to be the cause of the high instream fecal coliform numbers. Upstream and
downstream fecal coliform monitoring was removed from the permit.
Page 4 of 8

Supporting Material
Fact Sheet
NC0085359
I. Evaluation of Proposed Expansion
The following factors were considered in support of the proposed expansion from 6 MGD to 12 MGD:
1. SEPA Environmental Assessment (EA) Review. Pursuant to the requirements of the NC
Environmental Policy Act, an Environmental Assessment was prepared by Union County Public
Works for the proposed expansion. A Finding of No Significant Impact (FONSI) was
subsequently issued on September 13, 2013. The EA considered five options for wastewater
treatment: (a) no action; (b) purchase treatment capacity at the Charlotte McAlpine Creek facility;
(c) purchase treatment capacity at the Lancaster County Water and Sewer District (LCWSD)
Indian Land WWTP in South Carolina; (d) partner with LCWSD for a new WWTP; and (e)
expand the existing Twelve Mile Creek WWTP from 6 to 12 MGD. Expansion of the existing
Twelve Mile Creek WWTP was selected. Additionally, Union County evaluated wastewater
alternatives in accordance with NCDWR Engineering Alternatives Analysis (EAA) guidelines.
The Division concurs with the EA conclusion that the most environmentally sound, reasonably
cost-effective option is expansion of the existing Twelve Mile Creek WWTP. The 20-year
present worth costs for the selected alternative ($97 Million) is significantly less than non -
discharge options (land application, $199 Million; reuse spray irrigation, $235 Million) as well as
alternative discharge options (Discharge to Catawba River in South Carolina, $117 Million). The
Division also concurs with the 20-year flow projection of 12 MGD (projected maximum month)
based on reasonable population growth estimates and wastewater flow assumptions. Wastewater
flow projections were based in part on the County's Comprehensive Water and Wastewater
Master Plan (Black and Veatch, 2011).
2. Water Quality Modeling Results. Modeling of predicted instream dissolved oxygen (DO) levels
using the Division's Streeter -Phelps -based model were limited in application for Twelve Mile
Creek. Therefore, modeling efforts based on a more representative QUAL2E model to evaluate
assimilative capacity were conducted by Tetra Tech and are presented in two Tetra Tech reports:
(a) Scoping Level Assessment of Assimilative Capacity in Twelve Mile Creek Below the Union
County WWTP (April 2010), and (b) QUAL2 Model Update for Twelve Mile Creek below the
Union County WWTP (February 2012). The scoping level QUAL2 model results suggested that
instream DO concentrations would be expected to increase well above natural background
conditions as a result of increased flow velocity with resultant increase in reaeration, thus there is
additional assimilative capacity for expanded flow. Following this scoping level assessment,
additional instream data collection efforts were undertaken to help with model refinement. The
Updated QUAL2E stream water quality model incorporated additional downstream survey
information, verification of model assumptions, and model recalibration. The updated modeling
results validated the primary conclusion of the scoping level QUAL2E analysis- that there is
additional assimilative capacity available and the wastewater discharge is not predicted to
negatively impact instream DO leve s ow 1 he model scenario results indicate
that an increased wastewater discharge (i.e., up to 12 MGD) would raise the DO levels
throughout the pooled sections; in contrast, complete removal of the discharge was predicted to
- d asse DO levels in pooled zones by more than 1 mg/1.
3. eculat i its. Based on results of the Union County instream DO study conducted during
Summer 2009 as we - as the QUAL2E scoping levelassessment, the Division provided
speculative limits for 9MGI , 2 MGD, and 15 MGD on September 1, 2010.
4. Antidegradation Review. Per NC requirements (15A NCAC 2H.0105(c)(2), the applicant
prepared an Engineering Alternatives Analysis that considered non -discharge alternatives. The
applicant also conducted water quality modeling that projected improved DO conditions with the
discharge. Finally, the proposed expansion will meet the long-term wastewater needs in the
Twelve Mile Creek service area.
5. Elimination of NPDES Discharges to Goose Creek. Goose Creek was identified as a waterbody
with aquatic life concerns due to the presence of the federally -endangered Carolina heelsplitter
Page 5 of 8

Supporting Material
Fact Sheet
NC0085359
mussel, which ultimately led to the development of a Site -Specific Water Quality Management
Plan adopted into Rule in 2009 (15A NCAC 2B.0600-.0609). In May 2006, Union County
proactively rerouted their wastewater flow away from their Hunley Creek WWTP (NC0072508)
which discharged directly to Goose Creek, and piped this flow to the Twelve Mile Creek WWTP.
Union County also connected the wastewater flow from Goose Creek Utilities/Fairfield
Plantation subdivision, which had also discharged directly to Goose Creek under NPDES Permit
NC0034762. Both NPDES permits with discharges to Goose Creek have been rescinded. The
shunting of wastewater flow away from Goose Creek and to Twelve Mile Creek is considered a
beneficial improvement in wastewater management in the area.
6. North Carolina's Natural Characteristics Rule. Instream data for Twelve Mile Creek indicates
that DO levels may on occasion fall below the State water quality standard of 5 mg/1, both above
and below the discharge. State regulation (15A NCAC 2B.0205, Natural Characteristics Outside
Standard Limits) provides that water quality standards will not be considered violated when
values outside the normal range are caused by natural conditions. For wastewater discharges to
such waters, the discharger will not be considered a contributor to substandard conditions
provided maximum treatment in compliance with permit requirements is maintained and
therefore meeting the water quality standard is beyond the discharger's control. As previously
stated, instream data and water quality modeling results indicate that Twelve Mile Creek is
naturally low in DO on occasions.
7. Compliance with South Carolina's 0.1 mg/1 DO Deficit Rule. Per the request of SC DHEC, Tetra
Tech refined the QUAL2E model further (specifically adjusting SOD rates), and evaluated the
proposed 12 MGD discharge to Twelve Mile Creek for compliance with South Carolina's water
quality standards, specifically the 0.1 mg/1 DO Deficit Rule (SC Regulation 61-68, Water
Classifications and Standards, Section D). The 0.1 Rule requires that waterbodies with naturally
low DO shall not be cumulatively lowered more than 0.1 mg/1 for DO (Daily Average) due to
point sources or other activities during Summer period (defined as March through October in
SC). SC DHEC (Heather Rizzuti, July 6, 2012) concluded that the refined QUAL2E model for
Twelve Mile Creek demonstrates overall compliance with the 0.1 Rule, and that the expanded
permit should maintain the critical Summer period of March -October as specified in the 0.1 Rule.
J. Monitoring Frequency Reduction Analysis
The County requested that monitoring be reduced for BOD5, TSS, ammonia -nitrogen, and fecal coliform
as allowed by DWR for "Exceptionally Performing Facilities." The data submitted for the reduction
request was reviewed. It should be noted that three years of daily effluent sampling data shall be reviewed
to assess the number of samples greater than 200% of the monthly average limit (weekly average limit for
fecal coliform). A review of effluent sampling data from 7/1/2011 through 6/30720J4confirmed that
sampling reductions for BOD5, TSS, and fecal coliform should be granted. Ammonia-nitroge -had -19
P g
daily va ues greater tin 200o-©fthe summer/winter monthly averagepermit limits. To qualify for the --
reduction no more than 15 daily sampling results shall be over 200% of the permit limit.
Monitoring for BOD5, TSS, and fecal coliform was reduced from daily to twice per week in the permit
renewal.
K. Summary of Proposed Changes
The following permit changes are proposed for this permit renewal/expansion:
1. Addition of 9 and 12 MGD effluent sheets for proposed phased expansion.
2. Addition of electronic DMR requirement.
3. Addition of Mercury Minimization Plan Requirement
4. Reduced monitoring for BOD5, TSS, and fecal coliform from daily to twice per week.
5. Removed instream monitoring for conductivity and fecal coliform.
Page 6 of 8

Supporting Material
Fact Sheet
NC0085359
6. Removed effluent monitoring for copper, zinc, and conductivity.
7. Removed Total Residual Chlorine limitation and monitoring. Facility uses UV disinfection.
8. Addition of revised Effluent Pollutant scan specifying three years of sampling and 2nd species
testing requirements.
9. Addition of revised Toxicity testing language
Proposed Schedule for Permit Issuance:
Draft Permit to Public Notice: September. 24, 2014 (est.)
Permit Scheduled to Issue: November 17, 2014 (est.)
State Contact:
If you have any questions on any of the above information or on the attached permit, please contact Julie
Grzyb at [phone] or julie.grzyb@,ncdenr.gov.
NAM
E:
DATE: // . (�
ADDENDUM ADDED 11/14/14
REGIONAL COMMENTS:
Comments were received from the Region on Oct. 28, 2014.
The parameter code for reporting Effluent Pollutant Scan data was added to the Effluent sheets as
requested and a parameter code has been requested for the TP 12-month rolling average so violations can
be tracked in BIMS. The County will be notified of the new TP code once IT develops it.
EPA REGION IV AND SC COMMENTS:
No comments were received from EPA Region IV or the South Carolina Permitting Unit.
PERMITTEE COMMENTS:
Several comments and requests were received from the County on Oct. 30, 2014. Responses to the
County's comments follow:
Reduce sampling for BOD5, TSS, and fecal coliform to "twice per month."
• The monitoring frequency for BOD5, TSS, and fecal coliform was listed incorrectly in the
draft permit. In accordance with DWR's Guidelines for Exceptionally Performing Facilities
it was changed to "twice per week." The Guidelines do not provide for a twice per month
allowance as requested by the County.
Remove instream samplingfor_ DO and Temperature.
• Instream sampling for DO and temperature remain in the permit. Continued instream
sampling will help to confirm the modeling predictions determined based upon the WWTP's
flow expansions. In addition, removal of the sampling requirements would require public
notice and approval bythe EPA.
Add an. Effluent Limitation and Monitoring Requirements sheet for
• As requested, an Effluent Limitation and Monitoring Requirements sheet was added for a
permitted flow of 7.5 MGD. See section A. (2).
Acid Standard Conditions from November 2011.
• The Standard Conditions from November 2011 have been attached to this permit.
Page 7 of 8

Supporting Material
Twelve -Mile Creek WWTP Permit Limits and rationale for limitations
Fact Sheet
NC0085359
EFFLUENT
CHARACTERISTICS
LIMITS.
RATIONAL FOR LIMITATION
Monthly
Average
Weekly
Average
Daily
Max.
Flow
Design
BOD, 5-day, 20°C
(March -October)
5.0 mg/L
7.5 mg/L
Based on results of the Union County instream DO study conducted
during Summer 2009 as well as the QUAL2E scoping level
assessment. See Speculative limits letter from NC dated 9/1/2010.
Seasonal Limits for BOD and NI-13-N necessary to comply with SC
water quality standards and their 0.1 mg/1 D.O. Rule.
BOD, 5-day, 20°C
(November —February)
10.0 mg/L
15.0 mg/L
Based on results of the Union County instream DO study conducted
during Summer 2009 as well as the QUAL2E scoping level
assessment. See Speculative limits letter from NC dated 9/1/2010.
Seasonal Limits for BOD and NH3-N necessary to comply with SC
water quality standards and their 0.1 mg/1 D.O. Rule.
Total Suspended Solids
30.0 mg/L
45.0 mg/L
Administrative Code 15A NCAC 2B .0400
NH3 as N
(March —October)
1.0 mg/L
3.0 mg/L
Based on results of the Union County instream DO study conducted
during Summer 2009 as well as the QUAL2E scoping level
assessment. See Speculative limits letter from NC dated 9/1/2010.
Seasonal Limits for BOD and NH3-N necessary to comply with SC
water quality standards and their 0.1 mg/l D.O. Rule.
NH3 as N
(November -February)
2.0 mg/L
6.0 mg/L
Based on results of the Union County instream DO study conducted
during Summer 2009 as well as the QUAL2E scoping level
assessment. See Speculative limits letter from NC dated 9/1/2010.
Seasonal Limits for BOD and NH3-N necessary to comply with SC
water quality standards and their 0.1 mg/1 D.O. Rule.
Dissolved Oxygen
Effluent -shall not be less than 6
mg/L
Based on results of the Union County instream DO study conducted
during Summer 2009 as well as the QUAL2E scoping level
assessment. See Speculative limits letter from NC dated 9/1/2010.
Dissolved Oxygen
Upstream and downstream
monitoring
Administrative Code 15A NCAC 2B .0500, verify model
pH
> 6.0 and < 9.0 standard units
NC WQS, Administrative Code 15A NCAC 2B "Red Book"
Total Nitrogen
(NO2+NO3+TKN)
Administrative Code 15A NCAC 2B .0500
Total Phosphorus
Monthly Average: 41.70 lbs/day
12 Month Avg.: 20.85 lbs/day
Union County /DWQ/SCDHEC Settlement Agreement for the
inclusion of phosphorus limits to dischargers to the main stem of the
Catawba (upstream of Lake Wateree), to comply with the SC lake
standard of 0.06 mg/1.
Temperature, °C
Effluent, upstream and downstream
monitoring
Administrative Code 15A NCAC 2B .0500, verify model
—
Fecal Coliform
(geo. mean)
200/100 mi
400/100 ml
NC"Water Quality Standard (WQS)
Chronic Toxicity\
1999 NC WET Policy — EPA approved
and Federal Regulations 40 CFR 122
Effluent Pollutant Scan
�-- Monitor and Report-----
40 CFR 122 and stated in EPA application (Form 2C)
Mercury
MMP Requirement
EPA Approved Hg TMDL and NC permitting Strategy (2012)
Copper
Removed - ---- --.
-116-reisonable potential shownsto Violate S WQS's
Zinc
Removed
No reasonable potential shown to Violate SC W '
Total Residual Chlorine
Removed
Facility only uses UV disinfection
Conductivity
Removed effluent, upstream and
downstream monitoring
No SIU's or CIU's discharge to the WWTP. Facility does not have a
pretreatment program. DWR guidance 4/22/2002
Fecal Coliform
(geo. mean)
Removed upstream and downstream
monitoring
Not a Class B water or impaired for fecal coliform. DWR guidance
4/22/2002. Instream data showed no impact from WWTP.
Page 8 of 8

AFFP
Public Notice North Carolina E
Affidavit of Publication
STATE OF NORTH
CAROLINA }
COUNTY OF UNION )
SS
Pat Deese, being duly sworn, says:
That she is Accounting Clerk of the The Enquirer Journal,
a daily newspaper of general circulation, printed and
published in Monroe, Union County, North Carolina; that
the publication, a copy of which is attached hereto, was
published in the said newspaper on the following dates:
September 26, 2014
That said newspaper was regularly issued and circulated
on those dates.
SIGNED:
Accounting Clerk
Subscribed to and sworn to me this 26th day of
September 2014.
Pamela D. Crump, Notary, Union County, North Carolina
My commission expires: July 10, 2018
30109930 30536193
NCDENR-131
1617 Main Service Center
Raleigh, NC 27699-1617
•''0.)" D. CRIB'
7:3% '°ve L\G
ti U1•1:ko%0
Om
Public Notice
North Carolina Environment-
al Management Com is-
.ion/NPDES Unit
1617 Mali Service Center
Raleigh, NC 27 99-1617
Notice of Intent to Issue a
N P DES Wastewater Permit
The NorthCarolina Environ-
mental Management Commis-
sion proposes to issue a N P-
D ES wastewater discharge
permit to the person(s) listed
below. Written comments re-
garding the proposed permit
will be accepted until 30 days
after the publish date of this
notice. The Director of the NC
Division of Water Resources
(DWR) may hold a public hear-
ing should there be a signific-
ant degree of public interest.
Please mail comments and/or
information requests to DWR
at the above address. Inter-
ested persons may visit the
DWR at 512 N. Salisbury
Street, Raleigh, NC to review
information on file, Additional
information on NPDES per-
mits and this notice may be
found on our website:
http://portal . noden r. o rg/web/wq
/swp/ps&npdes/calendar, or by
calling [phone]. Union
County Public Works reques-
ted renewal of Permit
NO0085359 for its Twelve Mile
Creek WWTP in Union
County; this permitted dis-
charge is treated municipal
wastewater to Twelve Mile
Creek, Catawba River Basin.
Sept. 26, 2014

Table II. Instream Monitoring Data
Upstream Downstream]
Tema 00 fe441roklorm so0440648 Tema D0 feW<enrorm conductivity
(C) (1,8/l( (rnb/l) gimbal/on (C) Im8/1) (011/1.) pmhes/on
4/11/2014 14.3 8.76 147 143 14 884 87 184
4/14/2014 15.9 8.69 94 1444 15.8 8.81 87 170
4/23/2014 16 8.82 67 122 16.2 8.79 40 157
4/28/2014 16.3 885 60 130 16.6 8.76 114 188
3/3/2014 10.2 9.76 94 165 10 9.85 127 243
3/10/2014 9.7 9.84 180 120 9.3 9.91 250 157
3/21/2014 9.3 10.35 133 138 9.3 10.33 80 186
2/24/2014 8.9 10.6 94 149 8.8 10.59 114 183
3/31/2014 11.1 8.59 113 153 10.5 8.75 130 203
2/6/2014 8.3 11.09 <1 102 8.5 11.16 <1 148
2/10/2014 7.4 10.45 53 168 7.1 10.6 20 224
2/19/2014 93 10.66 3700 105 9.6 10.41 4600 131
2/25/2014 102 10.11 210 143 9.7 10.08 187 206
1/6/2014 63 10.24 <1 103 6.6 10.19 <1 126
1/13/2014 6.3 8.77 <1 176 62 8.54 <1 233
1/23/2014 5.7 9.16 <1 173 5.9 9.47 <1 218
1/27/2014 8.3 10.26 <1 104 8.6 10.08 <1 118
12/2/2013 56 883 <1 162 5.6 10.11 <1 173
12/12/2013 6.9 11.37 <3 164 8.3 11.51 <3 303
12/17/2013 7.4 10.21 <1 151 7.9 10.34 <3 316
12/23/2013 164 702 50 82.9 15.9 6.12 <3 75.5
12/31/2013 9.1 7.59 250 113.9 8.6 10.34 <1 136.1
11/4/2013 10.1 4.35 83 268 - 10.1 4.77 134 271
11/14/2013 7.4 6.34 134 303 7.1 6.49 67 312
11/19/2013 7.1 4.98 117 309 7.1 5.17 150 312
11/25/1013 7 5 A3 <1 27 7 5.37 <1 230
10/2/2013 17.1 5.74 67 36. 17.1 5.29 50 137
10/7/2013 20.8 584 417 38 20.8 4.29 534 139
10/15/2013 20.4 539 150 46 20.4 5.87 250 147
10/21/2013 14.9 4.66 184 37 14.9 5.03 134 137
10/30/2013 13.2 4.7 117 72 13.2 4.94 67 274
deha
delta
Downstream II
ao000100 do.m<mtemo updown rend rm..
DO f.48140d4.lry 0rm raedurme di8 00d8
(C)Im/JL) (m8/1) pmhos/cm 01-08 01-00
14 3.66 74 211 0.18
152 8.73 67 193 008
16.2 8.94 114 206 -0.15
16.5 8.92 00 219 0. -0.16
10 9.82 114 296 0.06
9.3 1003 320 180 -0.12
10.4 10.17 113 211 -1. 0.16
10.6 1007 74 204 -1. 0.52
10.6 863 87 217 -0. 0.12
8.6 11.24 <1 209 -0. -0.08
8.3 1005 58 253 -1. 0.55
9.6 1057 5900 189 -0.16
10.1 9.97 220 224 -0. 0.11
6.6 10.43 <1 175 -0.29
6.4 8.69 <I 247 -0.15
5.9 9.31 <1 226 0.16
8.6 10.47 <1 149 -0.39
6 9.7 <I 197 -0 0.41
83 1089 <1 293 0.62
7.9 10.07 <1 304 0.27
355 78 42 758 0. -1.62
8.6 10.3 <1 131A 0.01
10.1 485 167 274 -003
7.1 6.73 17 300 0.24
7.1 5.26 167 303 .009
7 588 <1 228 -0.31
17.1 537 34 138 -0.08
208 6.41 300 140 -0.12
20.4 6.18 100 147 -0.31
149 5.18 117 137 -0.15
13.2 506 83 276 -0.12
9/3/2013 21.6 6.77 134
9/4/2013 21.6 6.78 134
9/5/2013 21.5 7.14 34
9/10/2013 21.7 6.39 67
9/11/2013 21.5 6.88 50
9/12/2013 21.7 6.73 33
9/16/2013 21.5 6113 60
9/17/2013 208 5.63 120
9/19/2013 18.1 4.16 40
9/23/2013 19.3 4.76 17
9/24/2013 19.4 5.11 84
9/35/2013 20.1 4.96 430
60 21.6 6.94 200 161
60 21.6 6.92 84 171
69 21.5 7.36 17 165
55 21.7 6.7 100 156
70 21.5 6.94 34 170
68 21.7 7.21 116 180
57 21.5 6.43 40 156
78 70.5 5.17 73 179
78 18.1 4.58 20 178
78 19.3 5.03 25 202
79 19.4 5.33 134 181
22 20.1 5.23 380 133
8/1/2013 21.7 6.38 3300 15 21.7 6.83 4800 115
8/5/2013 24.4 7.68 334 70 21.4 7.89 167 171
8/7/2013 21A 7.29 760 12 21.4 7.52 920 203
8/8/2013 21.5 6.89 150 76 21.5 7.14 233 177
8/12/2013 23 7.71 760 49 23 8.03 500 149
8/13/2013 22.5 7.86 620 70 22.5 7.97 440 174
8/14/2013 22.4 7.14 234 45 22.4 7.36 417 145
8/20/2013 21.4 7.69 2100 09 21.4 6.86 3200 110
8/21/2013 21.3 7.9 484 46 21.3 6.18 400 147
8/22/2013 214 7.33 200 61 21.4 7.61 234 141
8/26/2013 21.2 7.06 150 48 21.2 7.34 100 151
8/27/2013 21.6 6.74 134 44 21.6 7.19 150 146
8/28/2013 21.6 7.69 67 52 21.6 7.94 84 152
6 exceeded 400 6 exceeded 400
out of 13.46% out of 13.46%
7/3/2013 22.1 5.86 9300 72.3 22.2 6.37 9300 76.1
7/2/2013 21.7 6.43 700 164 21.7 6.55 400 1135
7/3/2013 21.3 6.19 3500 209 21.3 6.32 <1 140
7/8/2013 23 6.11 8900 97.9 23 6.14 9600 97.4
7/9/2013 22.6 6.19 520 140 22.6 6.38 440 140
7/10/2013 22 6.29 417 147 22 6.47 350 148
7/15/2013 22.5 6.49 420 114 22.5 6.78 1060 116
7/16/2013 22 689 167 153 22 7.02 300 153
7/17/2013 22 A 6.86 350 168 22.4 7.11 84 169
7/22/1013 232 5.88 2900 127 23.9 5.5 2100 157
7/23/2013 23.7 5.51 560 126 23.8 5.43 580 179
7/24/2013 238 5.96 200 132 24 5.48 7100 183
7/30/2013 218 6.74 420 167 21.8 6.98 560 187
7/31/2013 21.7 6.58 284 156 21.7 6.72 267 184
10 exceeded 400 8..ceded 400
out 4114. 71% eel of14• 57%
6/4/2013 21 6.54 580 140 21 6.79 1083 140
6/5/2013 21 6.31 945 192 21 6.47 340 255
6/6/2013 21 5.87 300 157. 21 6.28 270 160
6/11/2013 22.7 6.15 3300 94.3 228 5.86 4200 100
6/12/2013 204 6.67 380 190 20.4 6.98 400 134
6/13/2013 20.4 6.63 267 153 20.4 6.51 334 154
6/17/2013 21A 6.38 105 150 21.4 6.85 135 167
6/18/2013 21.7 6.16 5000 114 218 5.92 8200 115
6/19/2013 203 64 400 145 20.7 6.47 460 145
6/25/2013 22.1 5.91 3500 94.9 22.2 6.07 5600 115
6/26/2013 214 6.18 460 162 21.4 6.04 434 162
6/27/2013 218 5.78 420 210 212 6.06 284 136
7 exceeded 400 6 exceeded 400
eat of 12 458% e.to112450%
5/2/2013 15.2 11.18 1270 166 15.2 11.25 310 166
5/9/2013 15 11.26 110 172 15 10.88 185 172
5/16/2013 17 723 500 207 17 7.74 547 207
5/23/2013 19 7.38 2100 137 39 7.46 2800 138
5/30/2013 19 64 66 149 19 6.57 83 149
4/3/2013 13 9.18 126 144 13.3 9.26 116 144
4/11/2013 18.7 8.24 25 154 18.7 B.36 103 157
4/18/2013 13.4 6.38 112 152 18.3 6.4E 101 153
4/24/2013 13.9 7.94 260 163 15 7.57 380 211
3/7/2013 6.7 12.53 133 167 6.7 12.2E 56 169
3/14/2013 9.4 10.62 410 115 9.4 10.86 320 105
3/21/2013 3.6 11.19 53 143 9.3 10.17 48 169
3/25/2013 7.1 11.79 119 124 7.4 12.09 116 124
2/7/2013 62 6.18 410 159 6.3 6.37 133 237
2/14/2013 9.6 5.26 300 163 9.6 5.97 300 163
2/21/2013 5.2 6.98 420 162 5.2 7.26 360 162
2/23/2013 7.3 6.76 760 108 7.3 6.51 480 109
1/3/2013 8.6 787 112 106 6.6 8.21 310 124
-0.08
-0.12
0,03
0.07
-0.12
-007
0.05
0.01
-0.16
-0.07
-0.15
0.25
0.03
0.05
0.23
-0.31
0.18
-1.28
-0.14
-0.131 .
0.34
-2.75
-0.42
-015
-0.19
-0.14
045
-045
-048
-0.37
0.24
-0.17
-0.14
-0.22
-0.31
-0.06
-0.48
42.15
0.46
-0.42
.0.27
-0.27
.0.32
.0.45
.0.21
.0.23
-0.25
-0,32
-0.11
-0.22
0.83
.0.28
.0.23
47.28
-045
.0.25
0.51
.0.12
.0.13
-0.03
.0.19
.0.18
.0.29
.0.13
-0.25
0.32
008
048
-0.24
.0.14
.025
.0.16
-041
-0.31
0.12
-047
0.34
.007
-0.16
0.14
-028
-007
038
003
-0.08
-0.17
.0.08
.0.12
.0.1
0.37
025
-0.26
1.02
-03
0.19
0.11
0.28
0.25
-03
-0.1
0.2
36
-1274
35
0.3
58
-0.2
a4
0
78
37
48
-0.1
34
47.6
02
-03
03
-03
0.3
0.1
02
03
0
1.4
OS
-0S
-03
45
46
56
26
63
23
57
45
14
16
119
165
-7A
222
0
-03
0
0
0
0
0
0
0
0
0
1
0
0
0
0
0
-03
0
0
0
0
12
-1
1
0
24
2
-39
0
0
0
0
0
0
0
0
1
1
0
4
0
0
0
0
0
0
.20
3
2
0
0.1
0
0
0
38
21
-69
-03
0
0
0
0
0.1
0
1
2
0
30
0.1
53
02
56
0
20
0
28
0
0
0
tat
0.1
5.7
0
-56
0
0
0.1
1
17
-0.1
0.1
0
0
20.3
0
0
-74
0
0
0
0
0
03
0
-0.1
1.1
0
0
1.2
03
48
.1
46
78
0
0
0
0
0
0
21.6 7.23 100 161 -0.29
21.6 704 217 170 -0.12
21.5 7.51 84 160 -0.15
21.7 688 50 158 -0.18
21.5 7.17 17 166 -0.23
21.7 7.21 83 366 0
21.5 691 27 158 -0.48
22.1 5.17 210 370 -1. 0
18.1 507 74 178 -0.49
19.3 5.18 13 201 -0.15
194 5.67 50 183 -0.29
20.1 547 440 198 -0.19
21.7 6.94 5700 115 0.11
21.4 8.34 234 171 -045
21.4 7.73 580 173 -0.21
21.5 7.33 100 175 -0.19
23 8.19 860 149 -0.16
22.5 9.36 920 154 .0.39
22.4 7.78 234 145 .0.42
21,5 785 4900 125 -0. -0.99
21.3 8.31 367 147 -0.13
21.4 796 350 158 .0.35
21.2 7.68 267 155 -0.34
21.6 7.4 250 146 -0.21
21.6 807 150 152 -0.13
5 exceeded 400
out of 13. 39%
22.2 683 10300 75.2 -0.46
21.7 6.35 600 185 0.2
21.3 6.51 3800 160 -0.19
23 6.33 9100 97.4 -0.19
22.6 654 580 141 -0.16
22 654 450 148 -0.07
22.5 681 820 117 .0.03
22 7.17 200 153 -0.15
22.4 702 317 169 0.09
238 599 800 150 0. -0.49
238 593 840 170 -0.5
23.9 5.99 83 183 0. 0.51
212 711 480 156 .0.13
21.7 7.04 384 214 -0.32
10 exceded 400
out ono. 71%
21 6.63 480 140 0.16
21 6.52 420 222 -0.05
21 615 450 160 0.13
22.7 706 2000 93 0. .1.2
20.4 643 394 135 0.55
20.4 6.75 250 154 .0.24
21.4 6.71 206 141 0.14
218 6.11 7400 115 -0.19
20.7 6.32 420 146 015
222 6.38 4200 112 -0.31
21.4 6.11 560 153 47.07
212 6 284 248 0.06
3 exceeded 400
out of 12.67%
15.2 11.39 1140 167
15 1107 200 174
17 7.69 560 207
19 755 3000 139
19 6.48 115 150
.0.14
-0.19
0.05
47.03
009
13.3 92 115 146 0,06
18.7 842 127 157 .006
18.3 642 113 154 006
14.7 7.65 13 210 0. -0.08
6.7 1237 39 169 -0.09
9.4 108 220 202 0.08
95 1093 60 183 0 -0.76
7.4 1201 122 125 0.08
6.8 649 8 374
9.6 5.13 220 9750
5.2 7,15 500 165
7.3 6.58 72 109
8.6 8.16 260 133
-0.12
0.24
0.11
-007
0.05

1/7/2013 7.4 8.2 63 102 7.4 8.34 132 121
1/17/2013 8.3 5.41 4600 102 8.3 5.27 3700 121
1/24/2013 7 5.39 300 157 7 5.54 150 222
1/29/2013 7.9 6.18 260 268 7.9 6.34 200 255
12/5/2012 16.5 5.36 <1 126 16.5 5.48 <1 175
12/12/2012 16.9 4.46 25 121 16.9 480 25 196'
12/17/2012 17.1 5.78 31 113 17.1 5.62 13 187'
12/27/2012 8.5 8A5 138 200 9.2 3.93 2567 85A.
11/9/2012 15.4 5.45 <1 233 17.8 6.41 <1 244
11/14/2012 17.4 5.39 <1 103 17.6 5.26 <1 151
11/19/2012 16.7 5.06 <1 107 16.7 5.96 <1 149
11/28/2012 16.1 6.17 12 117 16.1 6.34 <3 149
10/2/2012 22.9 3.19 32 126 23 3.06 38 172
10/10/2012 18.4 4.76 19 124 18.0 4.58 38 203
10/17/2012 19.8 4.28 19 108 19.8 4.99 7 133
10/22/2012 15.8 4.18 82 113 15.8 4.56 94 159
10/30/2012 16.8 3.09 25 110 16.8 3.21 19 136
9/4/2012 24.3 3.19 13 106 24.3 3.34 7 141
9/6/2012 23.3 3.18 <1 102 23.3 3.03 <1 102
9/7/2012 23.3 38 <1 114 238 3.88 <1 172
9/10/2012 20.4 3.24 <1 104 20A 8.57 <1 163
9/11/2012 20.7 3.06 <1 106 20.7 3.77 <1 164
9/12/2012 20.9 3.33 <1 113 20.9 3.56 <1 152
9/18/2012 22.7 38 75 113 22.7 3.64 50 152
9/15/2012 218 3.09 50 134 212 3.17 50 167
9/20/2012 20.4 2.53 13 113 20.4 3.15 38 166
9/24/2012 218 2.98 32 119 21.5 3.19 19 152
9/25/2012 22 2.97 7 131 22.1 3.19 13 174
9/26/2012 22.3 3.14 38 105 22.3 3.23 19 166
8/2/2012 248 3.68 <1 103 248 3.51 <1 139
8/3/2012 25 3.13 <1 106 25 2.95 <1 166
8/6/2012 25.3 3.11 <1 139 253 2.9 <1 163
8/5/2012 24.6 4.09 19 106 24.6 3.77 38 159
8/10/2012 24.3 386 44 101 24.3 3.62 38 119
8/13/2012 24.3 385 <1 117 24.3 3.94 <1 163
8/14/2012 24.1 3.19 <1 IDS 24.1 3.26 <1 109
8/16/2012 238 3.06 <1 123 238 2.92 <1 177
8/21/2012 24.4 3.08 56 112 24.4 3.19 106 159
8/22/2012 24.1 3.68 19 132 24.1 3.96 19 211
8/23/2012 24 2.78 19 119 24 2.93 13 178
8/27/2012 23.5 3.15 25 107 23.5 2.93 31 129
8/30/2012 241 2.99 <1 119 24.1 3.19 <1 167
8/31/2012 22.6 52 7 114 22.6 5.76 7 139
7/2/2012 22.6 5.18 50 119 22.6 5.35 50 133
7/3/2012 22.7 5.51 <1 143 22.7 5.43 <1 155
7/5/2012 24 0.13 <1 106 24 4.35 <1 147
7/9/2012 25 2.55 52 103 25 2.43 37 130
7/12/2012 248 3.25 81 116 248 3.11 69 163
7/13/2012 238 3.79 <1 108 23.8 3.65 <1 159
7/1E/2012 24.7 3.1 25 114 24.7 9.03 63 159
7/17/2012 24.6 3.17 117 118 24.6 3 81 140
7/18/2012 25.4 3.77 6 188 25.4 3.89 13 207
7/23/2012 25 3.76 25 128 25 9.85 32 211
7/24/2012 25.2 3.97 <I 106 25.2 3.84 <1 152
7/26/2012 24.7 3.15 <I 104 24.7 2.97 <I 149
7/31/2012 24.7 289 <1 130 24.7 2.77 <1 147
6/4/2012 14.4 3.61 206 114 14.4 8.88 210 158
6/5/2012 12.5 5.47 230 104 12.5 5.47 290 128
6/5/2012 12.1 6.19 113 108 12.1 6.35 52 179
6/13/2012 19.1 5.13 206 129 19.3 8.46 131 137
6/14/2012 20.1 6.85 1040 119 20.1 7.24 860 138
6/15/2012 20.3 6.53 31 103 20.3 6.64 44 154
6/18/2012 20.2 5.09 44 104 20.2 5.33 69 158
6/19/2012 20.5 9.97 94 135 20.5 5.13 100 170
6/22/2012 22.7 3.94 169 161 22.7 4.18 156 248
6/25/2012 22.5 4.57 44 133 22.5 4.79 50 170
6/25/2012 22.8 4.79 138 104 222 5.15 113 130
6/27/2012 21.4 5.06 169 129 21.4 5.13 94 170
1 exceeded 400 1 exceeded 400
out4112=3% outo112=8%
5/1/2012 11.1 8.18 194 109 11.1 8.38 150 138
5/1C/2012 13.9 8.7 163 139 13.9 8.61 225 219
5/17/2012 15.8 7A9 130 140 15.7 8.07 100 276
5/22/2012 12.2 7.48 88 104 12.2 7.58 100 156
5/31/2012 13.5 8.24 88 194 13.5 8.38 69 279
173 37 35 36 30
DOsamples fecal samples DO samples fecal samples
<4 m5/l >400 <4m8/1 >400
-0 14
0.14
-0A5
-0.16
.0.12
.0.38
0.16
0.12
.0.96
0.12
-0.3
-0.17
0.13
0.18
-0.11
-0.38
-0.12
47.19
0.15
-0.08
-533
-0.31
-0.18
0.16
-OAS
-0.27
-0.21
-0.22
-0.14
0.17
0.18
0.21
0.32
0.24
-0.09
-0.07
0.14
-0.11
-0.29
-0.2
022
.0.2
0,04
-0.17
0.08
-0.22
0.12
0.14
0.14
0.07
0.17
-0.12
-0.09
0.19
0.18
0.12
-0.27
0
-0.16
-0.33
-0.39
-0.11
-0 29
484
-0.24
-0.22
.0.36
-0,12
'0 2
0.09
-0.58
-0.14
0
0
0
0
19
19
65
-13
0
0
0
0.7
2.4
52
6VALUEI
6VAlUE1
804108I
11
02
48
0
42
0
32
0.1
46
0
79
0
25
0
0
0
46i
26'
35I,
0
0
58
0
59
0
58
0
39
0
34
0
53
43
0
33
01
43
0
61
0
96
0
60
0
24
0
53
0
18
0
46
0
43
0
49
0
47
0
79
0
59
0
22
0
48
25
0
14
0
15
0
41
0
27
0
47
0
51
0
45
0
22
0
19
0
83
0
46
45
0
17
0
44
0
24
0
71
0.2
0
19
0
51
0
54
0
35
0
87
0
41
0
26
0
41
0
29
0
80
-0.1
136
0
52
85
119
DI> 14000
0
•ofdown.up
temp samples
>2.8
130
temp - nochanf
7.4 8.28 63 168 0.06
8.3 5.39 4200 174 -0.12
7 6.08 113 269 .0.24
7.9 6.27 144 175 007
16.5 5.44 <1 229 0.04
16.5 4.9B 38 218' 0. -0.14
17.1 5.71 7 209' -009
9 8.7 3333 30.4' 0. -037
15.7 4.95 <1 237 2. 1.46
17.4 5.6 <1 168 0. -034
16.7 5.68 <1 163 -032
16.1 6.09 <1 184 025
• 23 3.11 57 235 -0.05
18.4 4.63 50 241 0.05
192 4.46 32 166 -0.07
152 4.32 73 186 024
16.8 3.03 13 147 0.18
24.3 3.2 <1 177 0.18
23.3 3.07 13 147 -0.04
238 3.69 <1 188 0.19
20.4 3.27 <1 211 5.3
20.7 3.52 <1 189 -0.05
20.9 3.48 6 195 0.08
22.7 3.76 25 196 -0.12
21.8 3.02 106 225 0.15
20.4 3.03 31 194 012
212 3.06 7 189 0.13
22.1 3.06 <1 213 0.13
22.3 3A9 13 198 0.19
248 3.57 <1 152 -0.06
25 3.28 <1 205 -033
25.3 298 <1 185 -0.08
24.6 3.91 13 183 0.14
24.3 3.74 25 133 -0.12
24.3 3.73 <1 202 0.21
14.1 3.24 <1 133 0.02
238 3.11 <1 218 -0.19
24A 3.13 69 196 0.06
24.1 3.37 13 236 0.09
24 223 50 192 0.15
23.5 3.24 6 161 -0.31
24.1 3.11 <1 210 0.08
22.6 5E9 25 172 -0.13
22.6 5.24 19 141 0.11
22.7 5.78 <1 158 -035
24 4.26 19 175 0.09
25 2.68 40 162 -0.25
248 3.27 75 188 -0.16
232 388 <1 130 -0.23
24.7 327 107 183 -0.24
24.6 2.93 100 163 0.07
25.4 3.66 6 226 0.23
25 3.89 50 226 -0.04
25.2 4A£ <1 197 -0.22
24.7 3.11 <1 183 0.14
24.7 3.13 <1 173 -0.36
14.4 8.74 300 179 0.14
12.5 5.7 340 152 -0.23
12.1 637 169 215 -0.22
19.3 8.37 220 183 0.09
20.1 741 1000 172 -0.17
20.3 6.64 44 134 0
20.2 5.26 56 173 0.12
20.5 4.91 113 218 0.22
22.7 4.03 69 272 0.15
22.5 4.64 131 205 0.15
22.8 5.03 100 147 0.12
21.4 5.18 150 186 0
11.1 8.51 113 157 0
13.9 8.64 144 225 0
15.3 7.84 180 286 .0./
12.2 7.66 125 181 0
13.5 8.65 138 298 0
36 32
DO samples fecal sa mples
<4 m5/l > 000
10 sample
where
DII> DI
1lsampks
whey
DI> DII
152
same temp
-0.13
0.03
0.23
-0.03
-0.27
64
where
DI> DII
105
DII> DI
same DO
4

Union County - 12 Mile Creek
NC0085359
Qw (MGD) = 12.00
IQ10S(cfs)= 0.09
7Q10S(cfs)= 0.10
7Q 10W (cfs) = 1.50
30Q2 (cfs) = NO 30Q2 DATA
Avg. Stream Flow, QA (cfs) = 72.70
Receiving Stream: Twelve Mile Creek
2014 Freshwater RPA - 95% Probability/95% Confidence
MAXIMUM DATA POINTS = 58
WWTP/WTP Class:
IWC @ 1Q1OS = 99.518459%
IWC @ 7Q10S = 99.465241%
IWC @ 7QIOW = 92.537313%
IWC @ 30Q2 = N/A
IWC @ QA = 20.372399%
Stream Class: C
Outfall 001
Qw = 12 MGD
PARAMETER
TYPE
(1)
STANDARDS & CRITERIA (2)
PQL
UNITS
REASONABLE POTENTIAL RESULTS
RECOMMENDED ACTION
NC WQS /
Chronic
Applied
Standard
'/2 FAV /
Acute
n
Max Pred
# Det. Cw Allowable Cw
Arsenic
Arsenic
C
C
50
10
FW(7Q10s)
HH/WS(Qavg)
ur2/1.
ug/L
0
0
0
0
N/A
N/:•\
Acute: NO WQS
_ _ _ _
Chronic: ---- 50.3-------------------------------
Chronic 49.1
all Pollutant Scan values <detection
Beryllium
NC
6.5
FW(7Q10s)
uelL
0
0
VA
Acute: NO WQS
_ _ --------
Chronic:6.5
all Pollutant Scan values < detection
---------------------------
Cadmium
NC
2
FW(7Q10s)
15
ug/L
0
0
N/.-\
Acute: 15.1
_ _
--------
Chronic:2.0
all Pollutant Scan values < detection
----------------------------
Chromium
NC
50
FW(7Q10s)
1022
ue/L
0
0
N :\
Acute: 1,026.9
_ _
--- _---
-- 50.3
Chronic:Acute:
all Pollutant Scan values < detection
----
------------------------
Copper (AL)
NC
13
FW(7Q10s)
18.5
ug/L
58
6
h 1
18.6
---- -------------------------------
Chronic: 13.0
No value > Allowable Cw
No RP, Predicted Max < 50% of Allowable Cw - No
Monitoring required
Cyanide
NC
5
FW(7Q10s)
22
10
ug/L
0
0
N'A
Acute: 22.1
_ _ ---- _
Chronic: —5.0 ---
all Pollutant Scan values < detection
------------------------- ---
Lead
NC
25
FW(7Q10s)
33.8
ug/L
0
0
N/A
Acute: 34.0
_ ---- _ ------------------------------
Chronic: 25.1
all Pollutant Scan values < detection
Nickel
NC
88
FW(7Q10s)
_6
ualL
(1
0
N/A
Acute: 262.3
-_ ---- _ _
—Chronic: 88.5---
all Pollutant Scan values < detection
----------------------------
Selenium
NC
5
FW(7Q10s)
56
ug/I.
0
0
N/A
Acute: 56.3
_ _ _
Chronic------5.0-------------------------------
all Pollutant Scan values < detection
Page 1 of 2
9595 FRESHWATER RPA2014 31.xlsm, rpa
9/2/2014

Union County -12 Mile Creek
NC0085359
2014 Freshwater RPA - 95% Probability/95% Confidence
Outfall 001
Qw=12MGD
Silver (AL)
NC
0.06
FW(7Q10s)
1.23
a ll.
0
0
N/A
Acute: 1.236
_ ---- _ _ --
Chronic: 0.060
all Pollutant Scan values < detection
------
---------------------
Zinc (AL)
NC
171
FW(7Q10s)
171
ug1L
58
58
68.0
Acute: 171.8
—
Chronic: ---_-- 171.9
No value > Allowable Cw
No RP, Predicted Max < 50% of Allowable Cw- No
Monitoring required
----------------------------
Page 2 of 2
9595 FRESHWATER RPA2014_31.xlsm, rpa
9/2/2014

REASONABLE POTENTIAL ANALYSIS
9
Copper (AL)
Use "PASTE SPECIAL
Values" then "COPY"
. Maximum data
points = 58
Date Data BDL=1/2DL Results
1 5/21/2013 < 5 2.5 Std Dev. 0.9237
2 5/29/2013 < 5 2.5 Mean 2.8069
3 6/4/2013 < 5 2.5 C.V. 0.3291
4 6/11/2013 < 5 2.5 n 58
5 6/18/2013 < 5 2.5
6 6/25/2013 < 5 2.5 Mult Factor = 1.00
7 7/2/2013 < 5 2.5 Max. Value 6.4 ug/L
8 7/9/2013 < 5 2.5 Max. Pred Cw 6.4 ug/L
9 7/16/2013 < 5 2.5
10 7/24/2013 < 5 2.5
11 7/31/2013 5.3 5.3
12 8/7/2013 < 5 2.5
13 8/14/2013 < 5 2.5
14 8/21/2013 < 5 2.5
15 8/28/2013 5.1 5.1
16 9/4/2013 < 5 2.5
17 9/11/2013 < 5 2.5
18 9/18/2013 < 5 2.5
19 9/25/2013 < 5 2.5
20 10/2/2013 < 5 2.5
21 10/10/2013 < 5 2.5
22 10/16/2013 < 5 2.5
23 10/23/2013 < 5 2.5
24 10/30/2013 < 5 2.5
25 11/6/2013 < 5 2.5
26 11/15/2013 6.4 6.4
27 11/21/2013 5.7 5.7
28 11/27/2013 5.1 5.1
29 12/4/2013 < 5 2.5
30 12/13/2013 < 5 2.5
31 12/18/2013 < 5 2.5
32 12/23/2013 < 5 2.5
33 12/30/2013 < 5 2.5
34 1/9/2014 5.2 5.2
35 1/15/2014 < 5 2.5
36 1/22/2014 < 5 2.5
37 1/28/2014 < 5 2.5
38 2/4/2014 < 5 2.5
39 2/10/2014 < 5 2.5
40 2/19/2014 < 5 2.5
41 2/24/2014 < 5 2.5
42 3/3/2014 < 5 2.5
43 3/10/2014 < 5 2.5
44 3/18/2014 < 5 2.5
45 3/25/2014 < 5 2.5
46 4/1/2014 < 5 2.5
47 4R/2014 < 5 2.5
48 4/15/2014 < 5 2.5
49 4/21/2014 < 5 2.5
50 4/28/2014 < 5 2.5
51 5/5/2014 < 5 2.5
52 5/14/2014 < 5 2.5
53 5/20/2014 < 5 2.5
54 5/29/2014 < 5 2.5
55 6/4/2014 < 5 2.5
56 6/12/2014 < 5 2.5
57 6/16/2014 < 5 2.5
58 6/23/2014 < 5 2.5
18
Zinc (AL)
Date Data BDL=1/2DL Results
1 5/21/2013 46 46 Std Dev.
2 5/29/2013 61 61 Mean
3 6/4/2013 54 54 C.V.
4 6/11/2013 40 40 n
5 6/18/2013 48 48
6 6/25/2013 52 52 Mult Factor =
7 7/2/2013 44 44 Max. Value
8 7/9/2013 40 40 Max. Pred Cw
9 7/16/2013 37 37
10 7/24/2013 44 44
11 7/31/2013 51 51
12 8/7/2013 46 46
13 8/14/2013 49 49
14 8/21/2013 45 45
15 8/28/2013 52 52
16 9/4/2013 52 52
17 9/11/2013 57 57
18 9/18/2013 54 54
19 9/25/2013 51 51
20 10/2/2013 57 57
21 10/10/2013 55 55
22 10/16/2013 52 52
23 10/23/2013 60 60
24 10/30/2013 65 65
25 11/6/2013 55 55
26 11/15/2013 57 57
27 11/21/2013 66 66
28 11/27/2013 65 65
29 12/4/2013 54 54
30 12/13/2013 47 47
31 12/18/2013 49 49
32 12/23/2013 60 60
33 12/30/2013 38 38
34 1/9/2014 47 47
35 1/15/2014 23 23
36 1/22/2014 49 49
37 1/28/2014 46 46
38 2/4/2014 60 60
39 2/10/2014 59 59
40 2/19/2014 37 37
41 2/24/2014 40 40
42 3/3/2014 49 49
43 3/10/2014 35 35
44 3/18/2014 32 32
45 3/25/2014 42 42
46 4/1/2014 51.2 51.2
47 4/7/2014 55.3 55.3
48 4/15/2014 47 47
49 4/21/2014 23 23
50 4/28/2014 32 32
51 5/5/2014 57 57
52 5/14/2014 56 56
53 5/20/2014 49 49
54 5/29/2014 57 57
55 6/4/2014 49 49
56 6/12/2014 53 53
57 6/16/2014 56 56
58 6/23/2014 68 68
Use "PASTE SPECIAL
Values" then "COPY"
. Maximum data
points = 58
9.6001
49.5776
0.1955
58
1.00
68.0 ug/L
68.0 ug/L
-1-
9595 FRESHWATER RPA2014_31.xlsm, data
9/23/2014

8/11/14 WQS = 12 ng/L MERCURY WQBEL/TBEL EVALUATION V:2013-5
Facility Name: Union County - 12 Mile Creek
Total Mercury 1631E PQL = 0.5 ng/L 7Q10s =
Date Modifier Data Entry Value Permitted Flow =
No Limit Required
MMP Required
0.100
12.000
cfs
WQBEL = 12.06 ng/L
47 ng/L
12/10/13 2.16 2.16 2.2 ng/L - Annual Average for 2013
5/14/14 1.27 1.27 1.3 ng/L - Annual Average for 2014
2/24/11 0.535 0.535 0.5 ng/L - Annual Average for 2011

Union County - Twelve Mile Creek
Monitoring Frequency Reduction Analysis
BOD
1)
Requirement: mean < 50% of monthly average
Caic. weighted monthly average
(7/12 ' 5) + (5/12 ' 10 7.083333 mg/L wt. monthly average
50%= 7.08/2= 3.54 2.83 mean < 3.54 or 50% of the weighted monthly average limitation
2) No more than 15 daily samples can be > 200% of the weekly summer(15 mg/L) or winter (30 mg/L) average limit
1 0
one daily sample > 200% of the summer or winter weekly average limit
3) Sampling results shall not show more than two non -monthly avg. limit violations in past year
Not more than 2 samples > 7.5 mg/L in the summer or 15 mg/L in the winter during the past year
2 samples > summer weekly limit in the past year
Reduce monitoring for BOD
Fecal Coliform
1) Requirement geomean < 50% of monthly average limit
50% of Monthly average limit of 200/100 mL
= 100/100 mL
3.57 < 100 or 50% of monthly avg.limit
2) No more than 20 daily samples can be > 200% of the weekly average limit
200/100 ' 400/100 mL = 800/100 mL
0
zero samples > 200% of the weekly average limit
3) Sampling results shall not show more than two non -monthly avg. limit violations in past year
Not more than 2 samples > 400/100 mL in past year
2 samples > 400/100 mL in last year
Statistically analysis shows Fecal Coliform sampling frequency can be reduced
NH3-N
7/12'1.0 mg/L + 5/12'2 mg/L = 1.42 mg/L weighted, annual monthly average
0.71 = 50% of wt. annual monthly average
1) 0.97 three-year average is > 50% of the weighted annual monthly average limit
2) 200% of summer monthly avg. limit = 2 mg/L summer values > 2
7/1/2011 - 6/30 2014 10
200% of winter monthly permit limit = 4 mgfL winter values > 4
7/1/2011 - 6/30 2014 9
no more than 15 daily samples shall exceed 200% of the monthly average
Results show 19 daily samples exceeding 200% of monthly average > allowance of 15
3) no more than two weekly average limit violations in 2012 (none shown)
Monitoring Frequency for NH3-N will remain at daily
Total Suspended Solids
1) 30 mg/L monthly average permit limit
15 = 50% of monthly average permit limit
Average= 5.48 three-year average is < 50% of the monthly average permit limit
2) 200% of monthly average permit limit= 60 mg/L
7/2011 thru 6/30/2014 0 no values > 60
no daily samples exceeded 200% of the monthly average limit
3) no weekly average limit violations during the past year (7/1/2013 - 6/30/2014)
Reduce Monitoring Frequency for TSS to 2/week

Peon ,14-tico.404-0,Y10014 Ptifilfs/L
UNION COUNTY
DEPARTMENT OF PUBLIC WORKS
500 North Main Street, Suite 500, Monroe, NC 28112
Phone: [phone] • Fax: [phone]
October 22, 2014
Ms. Julie Grzyb
Environmental Engineer, NPDES Wastewater
N.C. Department of Environment and Natural Resources
Division of Water Resources
1617 Mail Service Center
Raleigh, NC 27699-1617
RE: Comments on Draft NPDES Permit
Twelve Mile Creek Wastewater Treatment Plant
NC0085359 Union County Public Works
Dear Ms. Grzyb,
RECEIVED/DENR/DWR
OCT 3 0 2014
Water Quality
Permitting Section
Union County Public Works Department received the Draft National Pollutant Discharge
Elimination System (NPDES) permit for our Twelve Mile Creek Wastewater Treatment
Plant (WWTP) in September 2014. We have reviewed our draft permit and wish to provide
the following comments to the Division of Water Resources (DWR):
1. In the effluent limits table in Sections A.(1), A.(2), and A.(3), modify the monitoring
frequency for winter and summer biochemical oxygen demand (BOD), total
suspended solids (TSS), and fecal coliform. The monitoring frequency in our draft
permit currently states that BOD, TSS, and fecal coliform shall be monitored "twice
per day." DWR's cover letter dated September 24, 2014 states that our monitoring
frequency will be reduced to "twice per week" for these three parameters per
DWR's Guidelines for Exceptionally Performing Facilities. However, we respectfully
request a reduction in monitoring for BOD and TSS from twice per week to twice
per month, as our facility consistently meets and exceeds an 85 percent removal
rate for BOD and TSS.
2. We respectfully request that the instream monitoring requirement for dissolved
oxygen be removed from the permit (Sections A.(1), A.(2), and A.(3)). 15A NCAC
2B requires instream monitoring for parameters that are "water quality limited." A
water quality limited segment is defined in NCAC as a segment "where it is known
that water quality does not meet applicable water quality standards or is not
expected to meet them even after the application of minimum treatment
requirements." Per the Fact Sheet and the Draft 2014 303(d) list, Twelve Mile

UNION COUNTY PUBLIC WORKS
Creek is no longer considered impaired for dissolved oxygen due to naturally
occurring conditions. The Twelve Mile Creek receiving stream does not meet the
definition of "water quality limited." As such, the associated instream monitoring
should be removed from the permit.
3. We respectfully request that the instream monitoring requirement for temperature
be removed from Sections A.(1), A.(2), and A.(3) of the permit. Twelve Mile Creek
is not listed as impaired for temperature on the draft 2014 303(d) list; therefore, the
instream monitoring requirement should be removed. The Fact Sheet points out
that the upstream and downstream temperatures do not vary by more than 2.8°C
the majority of the time based on 173 data points.
4. We respectfully request that a new Effluent Limitation and Monitoring
Requirements sheet be provided for a 7.5 million gallon per day (mgd) flow
condition. We understand that effluent limits and monitoring requirements will be
the same as those stipulated for the 9 and 12 mgd flow conditions.
5. Lastly, we also respectively request that the revised November 2011 standard
conditions be attached to the permit.
We are pleased that the copper and zinc limits have been removed from the draft permit.
Recent correspondence with DWR staff prompted a request to document the results of the
County's 2005 Water Effect Ratio (WER) study for copper and zinc and the associated
total recoverable criterion. Attached to this correspondence is a Technical Memorandum
prepared by Hazen and Sawyer (dated October 15, 2014) documenting the results of the
WER study and the total recoverable criterion for both metals.
We understand that Charlotte Mecklenburg Utility Department (CMUD) has negotiated a
bubble permit for total phosphorus applicable to several of CMUD's wastewater facilities
(i.e., Irwin Creek, Sugar Creek, and McAlpine Creek) that discharge into tributaries of the
Catawba River. We are taking this opportunity to express our intent to request that the
Twelve Mile Creek WWTP be included in this bubble permit sometime during our next
NPDES permit cycle ending November 2019. We do not want to delay the approval of this
current permit renewal/expansion; however, we feel that there should be a more equitable
distribution of effluent total phosphorus discharged in the Catawba River watershed. We
look forward to discussing this in greater detail with the NPDES Wastewater Unit in the
near -term.
In conclusion, we appreciate the time and effort of the NPDES Wastewater Unit to
consider our requests for this permit renewal. Please do not hesitate to call myself
2 of 3 10/24/2014

UNION COUNTY PUBLIC WORKS
(704-296-4210) or Jim Struve with Hazen and Sawyer (704-941-6046) if you have any
questions.
Sincerely,
Edward Gfscicki, PE
Executive Director
Union County Public Works
Enclosures:
Technical Memorandum: Site -Specific Water Effect Ratio Study Results and Total Recoverable
Criterion for Copper and Zinc, Twelve Mile Creek WWTP, Union County Public Works Department
cc: Scott Honeycutt, Union County
Jim Struve, P.E., Hazen and Sawyer
3 of 3 10/24/2014

MRo Ae) 644,4404 1VQ/NFf (Imolai-
Subject:
Importance:
Julie,
.Grzyb, Julie
From: Allocco, Marcia
Sent: Tuesday, October 28, 2014 2:32 PM
To: Grzyb, Julie
Cc: Belnick, Tom; Hennessy, John; Poupart, Jeff; Parker, Michael; Manuel, Vanessa; Moore,
Tom; Smith, Jennifer; Denard, Derek
Comments for draft permit for NC0085359 Union County Twelve Mile Creek WWTP -
Parameter codes needed
High
A copy of the draft permit for the Twelve Mile WWTP landed in my Inbox recently and I had a chance to review it
yesterday. I did want to highlight a few things I see as possible issues going forward when the permittee attempts to use
eDMR to submit their monitoring reports within 270 days of the final issuance of the permit. I have highlighted my
thoughts below and they are based on providing good customer service to our permittees but also to reduce manual
permit limit violation review by the Mooresville Regional Office. If you have any questions regarding my comments
please let me know.
Thanks for your consideration and assistance,
Marcia
• The eDMR system is based on the EPA parameter code that is specified in BIMS to facilitate the electronic
reporting of all permit required monitoring. Recently, there have been some changes to the codes to ensure
the data is up loaded correctly into the EPA data system (change from PCS to ICIS), and we understand that
many of our permittees were not made aware of this by the Division. For this reason, this Office recommends
that the parameter codes be provided as part of the paper permit issued to the permittee as we feel this is not
only good customer service, but also prevents incorrect reporting of data. We have seen great success in using
the eDMR system on the first attempt by our minor permittees that had the codes provided by the Division in
their paper permit. Such being the case, this Office is requesting that the respective parameter codes be added
to the permit before it is issued. Specific instances where this will be invaluable to both the permittee and the
regional office will be highlighted below.
• As part of the eDMR rollout a parameter code has been developed for reporting the annual pollutant scan data,
which is NC01; the permittee will not be aware of this code unless it is provided to them.
J • The Twelve Mile WWTP is part of the nutrient TMDL developed for the Catawba River. This facility along with a
few others in our region must report 12-month rolling average phosphorous concentration monthly. The
permit as written continues this requirement and requests that a paper summary of the rolling average be
submitted. Unfortunately, this paper reporting necessitates a manual review of the submitted report for each
G`�`
a (v monitoring month. If there is a violation MRO staff must then manually create a violation in BIMS. It is my
understanding from discussion with DENR IT staff that a parameter code could be developed to facilitate
t> electronic reporting of the rolling 12-month phosphorous average. With electronic reporting of the
phosphorous data BIMS could be used to flag violations relieving MRO staff from the monthly manual review of
permit limit violations. Therefore, this office is requesting that a parameter code be developed for the
phosphorous reporting and provided to the permittee before the permit is issued.
1

DWR
Division of Water Resources
Marcia Allocco, MS — Senior Environmental Specialist
NC Dept. of Environment & Natural Resources (NCDENR)
Division of Water Resources - Water Quality Regional Operations
610 East Center Ave., Suite 301, Mooresville, NC 28115
Phone: [phone] Fax: [phone]
marcia.allocco(&ncdenr.gov
www.ncwaterquality.orq
Please note that effective Oct. 15, 2013, the MRO copy fee is $0.05/page. This applies to all copies; the first 25 pages
are no longer free.
E-mail correspondence to and from this address may be subject to the North Carolina Public Records Law and may be
disclosed to third parties unless the content is exempt by statute or other regulation.
2

)yS3S1 5ep,1 WRVS/
60)r expulsion ('ay j1y0
FINDING OF NO SIGNIFICANT IMPACT AND ENVIRONMENTAL ASSESSMENT
UNION COUNTY PUBLIC WORKS — UPSIZING OF EXISTING INTERCEPTOR AND TWELVE
MILE CREEK WASTEWATER TREATMENT PLANT EXPANSION
Pursuant to the requirements of the North Carolina Environmental Policy Act (N.C.G.S. § 113A-1, et seg.),
an environmental assessment (EA) has been prepared by Union County Public Works (UCPW) for the
replacement of the existing East Fork Twelve Mile Creek and Davis Mine Creek interceptors and the
expansion of its Twelve Mile Creek Wastewater Treatment Plant (WWTP) from 6 to 12 million gallons per
day (MGD). Upsizing of approximately 37,000 linear feet (1.f.) of existing interceptor to prevent
surcharging and allow conveyance of wet weather flows will consist of (1) approximately 22,500 feet of
new 18-inch and 30-inch diameter interceptor replacing existing 12 inch, 15-inch, and 18-inch diameter
interceptor along the East Fork branch of Twelve Mile Creek; (2) approximately 7,300 feet of new 15-inch
and 24-inch diameter interceptor replacing existing 8-inch diameter interceptor along the East Fork Twelve
Mile Creek Unnamed Tributary 4; (3) approximately 2,900 feet of 12-inch diameter interceptor replacing
existing 8-inch diameter interceptor along the Tributary 1; and (4) approximately 4,500 feet of 12-inch
diameter interceptor replacing existing 8-inch diameter interceptor along Davis Mine Creek. Preliminary
engineering indicates that the WWTP 12 MGD treatment capacity expansion may include the following:
(1) Parallel influent pump station, screen replacements, fine screen facility, and influent flow equalization;
(2)Existing oxidation ditches modifications with new blowers, diffusers, air piping, and blower building;
(3) Additional activated sludge aeration basins to accommodate expanded flow; (4) Additional secondary
clarifiers and associated return activated sludge pumping facilities; (5) Additional tertiary filters;
(6) Additional UV facilities and cascade aerator; (7) A new gravity belt thickener and additional sludge
digesters; (8) Expansion of the odor control facility; and (9) Stand-by power facilities for the influent pump
station and coarse screenings facility.
Five alternatives were considered for wastewater treatment: (1) no action; (2) purchase treatment capacity at
the McAlpine Creek facility; and 3) purchase treatment capacity at the Lancaster County Water and Sewer
District (LCWSD) Indian Land WWTP; (4) partner with LCWSD for a new WWTP; and (5) expand the
existing Twelve Mile WWTP from 6 to 12 MGD. Option 5 was chosen for wastewater treatment. Four
effluent disposal alternatives were considered: (1) land application; (2) non -conjunctive reuse; (3) discharge
to Catawba River; and (4) expand existing discharge to Twelve Mile Creek. Option 4 was chosen for
effluent disposal.
Direct impacts have been avoided and minimized to the extent practicable during project planning . Noise
levels will temporarily increase in the immediate vicinity of construction locations. Nuisance noise levels,
which are currently not detectable from the WWTP, are only expected to increase negligibly when the new
expansion comes on-line. Operation of the expanded transmission lines will not create increased noise levels.
Minimal direct, permanent impacts to terrestrial habitat or wildlife are expected from construction or
operation of the proposed project. Topography and soils will be directly impacted by grading and filling
activities; however, most of these impacts will be short term direct impacts and will not result in permanent
impacts to the topography or soil. While the interceptor and potential new ancillary structures will be located
in the Special Flood Hazard Area and/or floodway, potential impacts to base flood elevations will be
negligible. Portions of the WWTP expansion will also be located within the Special Flood Hazard Base
Flood footprint, but no portion of the expansion will occur within the floodway. Direct land use impacts are
anticipated to be less than 0.1 acres along segments of the interceptor route that will be realigned outside of
the existing easement and may require the acquisition of additional easements that are currently maintained
as residential lawns, roadsides, and agricultural lands. Approximately 1 acre of forested area will likely be
temporarily removed to allow for interceptor relocation. Immediate local air quality at the construction sites
will be degraded by stirred dust and emissions from machinery, and the upgraded WWTP and wastewater
transmission infrastructure are not anticipated to significantly or negatively impact air quality. However, the
new generators proposed as a part of the WWTP expansion will require modification of the existing air
permit for standby emergency power generation. Construction associated with the WWTP expansion and

interceptor installation may cause surface water quality degradation from runoff and sedimentation. The
proposed interceptor will cross 13 waterways via open trench installation and associated dewatering of
immediate work areas; however impacts will be minimized by implementing a sediment and erosion control
plan. An area of herbaceous wetlands will be temporarily impacted during construction. Proper erosion and
sedimentation practices will be followed during construction to protect local water quality as well as aquatic
habitat and wildlife. Substantial nutrient loading to Twelve Mile Creek is not expected, and water quality in
the creek should improve over the long-term by reducing the impacts of nutrients in the watershed from
failing or inefficient wastewater treatment and disposal systems. Direct impacts to fish, shellfish, and their
habitats will be temporary and minor and associated with water quality impacts from construction/installation
activities, and construction schedule moratoria will be observed for the protection of nine fish species. There
will not be any significant direct negative impacts to prime or unique farmlands; public lands and scenic,
recreational and State natural areas; areas of archaeological or historical value; groundwater; or threatened or
endangered species; or toxic substances.
Secondary and cumulative environmental impacts (SCIs) may result from this project and are outlined in the
EA. Federal, state, and local programs and ordinances will help to offset potential SCIs resulting from the
proposed project. These programs include land use planning, open space preservation, erosion and
sedimentation control, stormwater, and floodplain management. In addition, Union County plans to amend
its Land Use Ordinance in order to adopt riparian buffer regulations and require Schweinitz's sunflower
surveys for new development in unincorporated areas of Union County within the Treatment Plant service
area. The conversion of septic systems to be sewered in the Goose Creek Watershed will comply with the
Site Specific Water Quality Management Plan for the Goose Creek Watershed. Therefore, the proposed
project should not result in significant SCI.
Based on the findings of the EA, the impact avoidance/mitigation measures contained therein, and reviewed
by governmental agencies, the Division of Water Resources has concluded that the proposed project will not
result in significant impacts to the environment. This EA and FNSI are prerequisites for the issuance of
Division of Water Resources permits necessary for the project's construction. An Environmental Impact
Statement will not be prepared for this project. This FNSI completes the environmental review record,
which is available for inspection at the State Clearinghouse.
North Carolina Department of Environment and Natural Resources
Division of Water Resources — Water Quality Programs
13 September 2013

. L4M&4/,u41lIl&k scPA 'IOW
HAzEN AND S&WYER
Environmental Engineers & Scientists
March 11, 2013
Hannah Headrick
SEPA Coordinator
Division of Water Quality
1617 Mail Service Center
Raleigh, NC 27699-1617
RE: Response to Agency Review Comments, DENR #1572
Environmental Assessment for Twelve Mile Creek WWTP Expansion
Union County Public Works Department
Dear Ms. Headrick,
Hazen and Sawyer, P.C.
4011 WestChase Blvd.
Raleigh, NC 27607
919-833-7152
The following are our responses to the North Carolina Division of Water Quality (DWQ) review comments
on the Environmental Assessment (EA) for the Twelve Mile Creek Wastewater Treatment Plant (VVWTP)
expansion:
1. The NPDES Unit concurs with the requested 20-year flow projection of 12 mgd based on reasonable
population growth estimates and wastewater flow assumptions.
Comment noted.
2. The NPDES Unit concurs with the EA conclusion that the most environmentally sound, reasonable
cost-effective option is expansion of the existing Twelve Mile Creek WWTP. The 20-year present
worth costs for the selected alternative ($97 million) is significantly less than non -discharge options
(land application, $199 Million; Reuse Spray Irrigation, $235 Million) as well as alternative discharge
options (Discharge to Catawba River in SC, $117 Million).
Comment noted.
e EA states that Union County stopped routing wastewater flow to the Hunley Creek WWTP
(NC0072508) in May 2006, and currently pumps that wastewater to either Twelve Mile Creek WWTP
or Crooked Creek WWTP for treatment Since that wastewater flow is accounted for in the Twelve
Mile Creek flow projections, the Division anticipates that Union County will request permit rescission
of the Hunley Creek NPDES permit prior to any permitting request for expansion of the Twelve Mile
Creek WWTP. Elimination of the Hunley Creek WWTP discharge permit will also be consistent with
the set of management rules adopted by the Environmental Management Commission in 2009 for
protection of the federally -endangered Carolina heelsplitter in the Goose Creek watershed. Please
provide an update on this action.
New York, NY • Armonk, NY • Woodbury, NY • Detroit. MI • Raleigh. NC • Charlotte. NC • Manta` GA • Fairfax, VA • Hollywood, FL *Boca Raton, FL • Fort Pierce. FL • Sarasota, FL • Miami, FL • Philadelphia, PA

HAZENANDSWWER
Page 2
The County intends to rescind the Hunley Creek V VTP NPDES permit as soon as a FONSI is issued
for the expansion of the Twelve Mile Creek WUVfP to 12 mgd. The request for permit rescission will
occur prior to a request for an NPDES permit modification for the expansion and prior to a request for
an Authorization to Construct (ATC).
We appreciate the opportunity to respond to comments on this project. If you have any questions, please
do not hesitate to call at 919-755-8650 or [e-mail].
Sincerely,
HAZEN AND SAWYER, P.
Mary E. dter, PE
Associate
Copies:
Ed Goscicki, PE, Director, Union County
Scott Honeycutt, PE, Engineering Division Manager, Union County
Amy Helms, PE, Water and Land Resources Division Manager, Union County
James Struve, Hazen and Sawyer
Steve Sands, Hazen and Sawyer

.
•
Belnick, Tom
From: Headrick, Hannah
Sent: Monday, March 11, 2013 8:56 AM
To: Belnick, Tom
Subject: FW: Response to Comments DENR 1572, Union County Twelve Mile Creek Wastewater
Treatment Plant Expansion
Attachments: L_DWQ_Twelve Mile Creek WWTP_March 2013.pdf
Tom —
Please find Union County's responses attached.
The main one of interest to you should be the third one.
don't think you need any further action here, but let me know.
Thanks.
Hannah
Hannah Headrick
SEPA Coordinator
NC Division of Water Quality - Planning Section
Physical location: 512 N. Salisbury Street, Raleigh, NC 27604 [Archdale Building - Office 625J]
Mailing address: 1617 Mail Service Center, Raleigh, NC 27699-1617
Phone: [phone] -- Fax: [phone]
http://portal.ncdenr.org/web/wa/ps/sepa
E-mail correspondence to and from this address may be subject to the North Carolina Public Records Law and may be disclosed to
third parties.
From: Sadler, Mary [maiito:[e-mail]]
Sent: Monday, March 11, 2013 8:06 AM
To: Headrick, Hannah
Cc: Edward Goscicki(edward.goscicki(aco.union.nc.us); Amy Helms (amymhelms(&co.union.nc.us); Struve, James N.;
Sands, Steve
Subject: Response to Comments DENR 1572, Union County Twelve Mile Creek Wastewater Treatment Plant Expansion
Hannah,
Please find attached our responses to DWQ's August 2012 comments on the Twelve Mile Creek WWTP Expansion EA.
Thank you.
Mary
1

ATA
NCDENR
North Carolina Department of Environment and Natural Resources
Division of Water Quality
Beverly Eaves Perdue Charles Wakild, P.E. Dee Freeman
Governor Director Secretary
Memorandum
To: Hannah Headrick, SEPA
NPDES Permit File NC0085359
Thru: NA
From: Tom Belnick, NPDES
Date: August 9, 2012
Subject: Review of SEPA EA for Union County Twelve Mile Creek WWTP Expansion
The following NPDES comments pertain to a proposed expansion of the Union County Twelve Mile Creek WWTP from
6 MGD to 12 MGD.
Wastewater Flow Projections
• The NPDES Unit concurs with the requested 20-year flow projection of 12 MGD based on reasonable population
growth estimates and wastewater flow assumptions.
Alternatives Analysis
• The NPDES Unit concurs with the EA conclusion that the most environmentally sound, reasonably cost-effective
option is expansion of the existing Twelve Mile Creek WWTP. The 20-year present worth costs for the selected
alternative ($97 Million) is significantly less than non -discharge options (land application, $199 Million; Reuse
Spray Irrigation, $235 Million) as well as alternative discharge options (Discharge to Catawba River in SC, $117
Million).
Other Comments
• The EA states that Union County stopped routing wastewater flow to the Hunley Creek WWTP (NC0072508) in
May 2006, and currently pumps that wastewater to either Twelve Mile Creek WWTP or Crooked Creek WWTP
for treatment. Since that wastewater flow is accounted for in the Twelve Mile Creek flow projections, the
Division anticipates that Union County will request permit rescission of the Hunley Creek NPDES permit prior to
any permitting request for expansion of the Twelve Mile Creek WWTP. Elimination of the Hunley Creek WWTP
discharge permit will also be consistent with the set of management rules adopted by the Environmental
Management Commission in 2009 for protection of the federally -endangered Carolina heelsplitter in the Goose
Creek watershed. Please provide an update on this action.
1617 Mail Service Center, Raleigh, North Carolina 27699-1617
Location: 512 N. Salisbury St. Raleigh, North Carolina 27604
Phone: [phone] FAX: [phone] Customer Service: 1-877-623-6748
Internet www.ncwaterquality.org
An Equal Opportunity \ Affirmative Action Employer
One
NorthCarolina
Naturally

OM-fr 2oiy e) 3o31d) (.i�f.
Catawba River Basin
2014 AU Number:
AU Name:
IAU Description:
AU Length Area:
AU Units:
Classification:
11-137-9d McAlpine Creek (Waverly Lake)
From NC 521 to North Carolina -South Carolina State Line
1.0 FW Miles
IRCategory: ACS: Parameter Of Interest:
Collection Year: 303(d) yr:
5 EC Benthos Fair (Nar, AL, FW)
1992 1998
11-137-7 McCullough Branch
From source to Sugar Creek
3.1 FW Miles C
IRCategory: ACS: Parameter Of Interest:
Collection Year: 303(d) yr:
5 EC Benthos Poor (Nar, AL, FW) 1990 1998
11-137-9-5 McMullen Creek
From source to McAlpine Creek
13.8 FW Miles C
IRCategory: ACS: Parameter Of Interest: Collection Year: 303(d) yr:
5 EC Benthos Poor (Nar, AL, FW) 2008 2010
11-138-3 Sixmile Creek 8.8 FW Miles C
From source to North Carolina -South Carolina State Line
IRCategory: ACS: Parameter Of Interest: Collection Year: 303(d) yr:
5 EC Fish Community Poor (Nar, AL, FW) 2012 2006
11-137a Sugar Creek 0.3 FW Miles C
From source to below WWTP, SR 1156, Mecklenburg
IRCategory: ACS: Parameter Of Interest: Collection Year: 303(d) yr:
5 EC Benthos Poor (Nar, AL, FW) 2002 1998
11-137b Sugar Creek 10.9 FW Miles C
From SR 1156 Mecklenburg to Hwy 51
IRCategory: ACS: Parameter Of Interest: Collection Year: 303(d) yr:
5 EC Copper (7 µg/I, AL, FW) 2008 2010
11-137c Sugar Creek 2.5 FW Miles C
From Hwy 51 NC/SC border
IRCategory: ACS: Parameter Of Interest: Collection Year: 303(d) yr:
5 EC Copper (7 µg/I, AL, FW) 2008 2010
11-138
Twelvemile Creek
From source to North Carolina -South Carolina State Line
3.0 FW Miles C
IRCategory: ACS: Parameter Of Interest: Collection Year: 303(d) yr:
5
EC Fish Community Fair (Nar, AL, FW)
2002 2010
Friday, February 21, 2014
draft 2014 NC 303(d) List -Category 5 assessments requiring TMDLs Page 20 of 148

I3S!'Chijb1y) 6eiw«vi Fih.n12011- a- &Ff niy
Catawba River Basin
11-139 Waxhaw Creek
2014 AU Number:
AU Name:
!AU Description:
AU Length Area:
AU Units:
Classification:
NC River Basin Catawba River Basin
Subbasin Catawba River
11-137-1 Irwin Creek
From source to Sugar Creek
11.8 FW Miles C
Parameter Recategorized
Turbidity (50 NTU, AL, FW miles)
Zinc (50 µg/I, AL, FW)
From To Justification
4t 1t The assessment and interpretation of more recent or more
accurate data in the record demonstrate the parameter of
interest is meeting criteria
5 3a1 Change in Assessement Methods per NC Environmental
Management Commission in 2013.
Lead (25 µg/I, AL, NC)
5 3a1 Change in Assessement Methods per NC Environmental
Management Commission in 2013.
11-137-8a Little Sugar Creek 11.6 FW Miles C
From source to Archdale Rd
Parameter Recategorized
Turbidity (50 NTU, AL, FW miles)
From To Justification
1t 4t New data indicate that water quality assessment criteria have
been exceeded
11-138 Twelvemile Creek 3.0 FW Miles C
From source to North Carolina -South Carolina State Line
Parameter Recategorized
Turbidity (50 NTU, AL, FW miles)
Dissolved Oxygen (4 mg/I, AL, FW)
From To Justification
5 1 The assessment and interpretation of more recent or more
accurate data in the record demonstrate the parameter of
interest is meeting criteria
5 1 The assessment and interpretation of more recent or more
accurate data in the record demonstrate the parameter of
interest is meeting criteria
Copper (7 µg/I, AL, FW)
5 3a1 Change in Assessement Methods per NC Environmental
Management Commission in 2013.
Ecological/biological Integrity FishCom (Nar, AL, FW) 4s 5 Pollutant causing impairment no longer exceeding criteria.
'. /k ,A / sapf to C4 hvi 7 Benthos or Fish Community continue to exceed criteria
fv V L ,
From source to North Carolina -South Carolina State Line
16.3 FW Miles C
Parameter Recategorized
Fish Community Good (Nar, AL, FW)
From To Justification
1 5 New data indicate that water quality assessment criteria have
been exceeded
Friday, February 21, 2014 draft water quality assessments recategorized from 2012 Assessments Page 19 of 83

2012 North Carolina 303(d) List -Category 5
FIk1Al 303fr) �1 Z
Catawba River Basin
> AU Number Name
10-digit Watershed 0305010301
Description
Length or Area
Sugar Creek
Units Classification Category
ICategory Rating Use Reason for Rating Parameter Year
> 11-137-1
Irwin Creek
From source to Sugar Creek
11.8
FW Miles C
5 Impaired Aquatic Life
5 Impaired Aquatic Life
5 Impaired Aquatic Life
Standard Violation Copper
Standard Violation Lead
Standard Violation Zinc
2010
2008
2010
5
> 11-137-7
McCullough Branch
From source to Sugar Creek
3.1 FW Miles C
5 Impaired Aquatic Life
Poor Bioclassification Ecological/biological Integrity Benthos
1998
5
> 11-137a
Sugar Creek
From source to below WWTP, SR 1156, Mecklenburg
0.3 FW Miles C
5 Impaired Aquatic Life
Poor Bioclassification Ecological/biological Integrity Benthos
1998
5
> 11-137b
Sugar Creek
From SR 1156 Mecklenburg to Hwy 51
10.9 FW Miles C 5
5 Impaired Aquatic Life
Fair Bioclassification Ecological/biological Integrity Benthos
2000
> 11-137c
Sugar Creek
From Hwy 51 NC/SC border
2.5 FW Miles C
5 Impaired Aquatic Life
Standard Violation Copper
2010
5
Catawba River Basin
10-digit Watershed 0305010302
12-digit Subwatershed
030501030202
Twelvemile Creek
East Fork Twelvemile Creel
> 11-138
Twelvemile Creek
From source to North Carolina -South Carolina State Line
3.0 FW Miles C
5 Impaired Aquatic Life Standard Violation Copper
5 Impaired Aquatic Life Standard Violation Turbidity
5 Impaired Aquatic Life Standard Violation Low Dissolved Oxygen
2008
2008
2012
5
12-digit Subwatershed
030501030203
Sixmile Creek
Friday, August 24, 2012
Approved by EPA August 10, 2012
Page 36 of 170

6'!? Alco-obssl Wilt4pfaisi"vitnode 7/2Q/L
Belnick, Tom 7))i Z ki/t - /41P41"4(... �jA1,� On OPSZ4fr7 S�iY
From: Behm, Pamela
Sent: Friday, March 02, 2012 9:27 AM
To: Belnick, Tom; Headrick, Hannah
Subject: FW: Twelve Mile Creek station question
o &cri� •i
o a NV� ��Jit+ Nl
a € &Alf ra 5 A 104 0 12,
FYI — the station that impaired twelve mile creek is upstream of the discharge, so I think we're ok with the new listing on
303(d) issue.
rci&ii' Ail 14 tql
�c,�J�et�- Ltc140n0r01.
E-mail correspondence to and from this address may be subject to the North Carolina Public Records Law and may be disclosed to third parties.
From: Krebs, Rob
Sent: Friday, March 02, 2012 9:06 AM
To: Behm, Pamela
Subject: FW: Twelve Mile Creek station question
FYI
From: Hood, Donna
Sent: Friday, March 02, 2012 9:05 AM
To: Krebs, Rob
Cc: Allocco, Marcia
Subject: RE: Twelve Mile Creek station question
C9819500 is upstream of the discharge, yes.
From: Krebs, Rob
Sent: Friday, March 02, 2012 7:05 AM
To: Hood, Donna
Cc: Allocco, Marcia
Subject: FW: Twelve Mile Creek station question
Donna,
Do you remember the location of the station with respect to the outfall. I too believe it was above the outfall as Union
Co was saying they will actually raise the DO in the stream if expansion is allowed. I know you spent a lot of time out
there sampling with Union Co.
Rob
From: Behm, Pamela
Sent: Thursday, March 01, 2012 4:16 PM
To: Krebs, Rob
Subject: Twelve Mile Creek station question
Hi Rob,
We had a meeting today with Union County to talk about possible expansion of the Twelve Mile Creek WWTP. Twelve
Mile Creek is listed on the draft 2012 303(d) list for low DO, based on monitoring results from station C9819500, at
1

NC16. It looks like this station is above the outfall for the WWTP. Can you check with your staff to see if they can
confirm that this is the case?
Thanks very much and please let me know if you need any additional info.
Pam
***************************************************************
Pam Behm
NC DWQ Modeling and TMDL Unit
1617 Mail Service Center
Raleigh, NC 27699
Email: [e-mail]
Phone: [phone]
Fax: [phone]
E-mail correspondence to and from this address may be subject to the North Carolina Public Records Law and may be disclosed to third parties.
2

trarl 7,00 3,03/a)
All Waters in NC are in Category 5-303(d) List for Mercury due to statewide fish consumption advice for several fish species
AU_Number
I'araumtei
AU_Name
Q 11-138-3 Sixmile Creek
AU_Description
Reason tin Rating
5 Ecological/biological Integrity FisI1( onl
Q 11-138 Twelvemile Creek
Copper — 51-I-ri/ye(1f1.'Ir4114
hurbidit}
LengthArea AU_Units Classification
(Ise Category
Collection Year 303“11year
From source to North Carolina -South
Carolina State Line
Fair Rioclassilieation
Aquatic Life
8.8 FW Miles C
2002
2006
From source to North Carolina -South
Carolina State Line
Standard Violation
Aquatic Life
3.0 FW Miles C
2006 2008
fq.itifOL
1(1" 444MAri
91/21/
Standard Violation
Aquatic Life
_ Specs
EP/16140/4a)di1cuJ14y'i �/,7/Z0ry
Otcit
2008 2008
NC 2010 Integrated Report Category 5-303(d) List EPA Submittal 20100329
Monday, March 29, 2010 Page 23 of 115

zooS (0?,(eotj
Catawba River Basin
Catawba River 8-Digit Subbasin 03050103
Assessment Unit Number
Description
Classification Old DWQ Subbasin Miles/Acres
Name
Use
Support
Category
Use
Support
Rating
Reason for
Rating
Parameter of
Interest
Collection Listing IR
Year Year Category
11-137-9d McAlpine Creek (Waverly Lake)
From NC 521 to North Carolina -South Carolina State Line
03-08-34 1.0 FW Miles
Aquatic Life Impaired Fair Bioclassification
Recreation Impaired Standard Violation
Ecological/biological Integrity 1992 1998 4s
Benthos
Fecal Coliform (recreation) 2006 1998 4a
11-137-7 McCullough Branch
From source to Sugar Creek
C 03-08-34
3.1 FW Miles
Aquatic Life Impaired Poor Bioclassification
Ecological/biological Integrity 1990 1998 5
Benthos
11-138-3 Sixmile Creek
From source to North Carolina -South Carolina State Line
03-08-38 8.8 FW Miles
Aquatic Life Impaired Fair Bioclassification
Ecological/biological lntegrity 2002 2006 5
FishCom
11-137a
Sugar Creek
From source to below WWTP, SR 1156, Mecklenburg
C 03-08-34 0.3 FW Miles
Aquatic Life Impaired Poor Bioclassification
Ecological/biological Integrity 2002 1998 5
Benthos
11-137b Sugar Creek
From SR 1156 Mecklenburg to Hwy 51
C 03-08-34
10.9 FW Miles
Aquatic Life Impaired Standard Violation
Aquatic Life Impaired Poor Bioclassification
Recreation Impaired Standard Violation
Turbidity 2006 2000 4a
Ecological/biological Integrity 2002 1998 4s
Benthos
Fecal Coliform (recreation) 2006 2000 4a
11-137c
Sugar Creek
From Hwy 51 NC/SC border
C 03-08-34
2.5 FW Miles
4_11-138 Twelvemile Creek
From source to North Carolina -South Carolina State Line
C 03-08-38 3.0 FW Miles
Aquatic Life Impaired Standard Violation
Aquatic Life Impaired Fair Bioclassification
Aquatic Life Impaired
Recreation Impaired
Standard Violation
Standard Violation
Aquatic Life Impaired Standard Violation
Aquatic Life Impaired Standard Violation
2006 2008 5
Ecological/biological Integrity 2002 1998 4s
Benthos
Turbidity 2006 2000 4a
Fecal Coliform (recreation) 2006 2000 4a
Copper 2006 2008 5
Turbidity 2006 2008 5
Copper
Chowan River Basin
25a1 CHOWAN RIVER
From North Carolina -Virginia State Line to near Riddicksville
B;NSW 03-01-01 1.8 FW Miles
Nottoway River 8-Digit Subbasin 03010201
Aquatic Life Impaired Standard Violation Low Dissolved Oxygen 2006 1998 5
Fish hnpaired Standard Violation Mercury 2002 2002 5
Consumption
25a2a CHOWAN RIVER
From near Riddicksville to Deep Creek
B;NSW 03-01-01
24.4 FW Miles
Aquatic Life Impaired Standard Violation
Fish Impaired Standard Violation
Consumption
Cadium
Mercury
2006 2008
2002 2002 5
All NC Waters are in Category 5 due to statewide Fish Consumption Advice for Mercury Category 5 Assessments require TMDL development per Clean Water Act Section 303(d)
2008 North Carolina Integrated Report Category 4 and 5 Impaired Waters List- 2010311 Page 25 of 139

twelve mile creek?4eiSJ�w+ A ►rts►e,4
310
Subject: twelve mile creek
From: Cam Mcnutt <[e-mail]>
Date: Tue, 31 Mar 2009 11:45:38 -0400
To: Tom Belnick <[e-mail]>
For Draft 2008 Integrated Report it is impaired for Turbidity but not DO. That was
based on 2002-2006 data window.
Biology for fish and bugs is GoodFair. The fish data from 2002 were used for the
2008 asmnt. Not sure when the next sample date is for biology
We are still in conference with EPA on the 2008 methods so there could potentially be
metals impairments as well but we really do not know yet.
I am expecting the2010 data set (2004-2008) anytime rigN and will have a better idea
on any DO issues.
Fels high and if we did a 5 in 30 sampling would likely be Impaired for
recreation also. e...
Cam McNutt
Water Quality Assessment Coordinator
NC Department of Environment and Natural Resources
Division of Water Quality Planning Section
1617 Mail Service Center
Raleigh NC 27699
(919)-807-6435
E-mail correspondence to and from this address may be subject to the North Carolina
Public Records Law and may be disclosed to third parties.
1 of 1
3/31/2009 11:58 AM

Re: [Fwd: Re: 303(d) for 12 Mile Crk, Catawba Basin, 030838]
• Subject: Re: [Fwd: Re: 303(d) for 12 Mile Crk, Catawba Basin, 030838]
From: Toya Fields <[e-mail]>
Date: Wed, 21 Jan 2009 11:09:12 -0500
To: Tom Belnick <[e-mail]>
Yeah, we told them that they couldn't have specs for that. We can talk- 715-0389. I have a bunch of
stuff that I did for that request.
Toya
Tom Belnick wrote:
MJ e i44 4O
®bv'l - esg0 ,
NF13 -14,1
Toya- I'll probably need to talk with you on this one- what's your new phone #.
Subject:
Re: 303(d) for 12 Mile Crk, Catawba Basin, 030838
From: Cam Mcnutt <[e-mail]>
Date: Wed, 21 Jan 2009 10:40:24 -0500
To: Tom Belnick <[e-mail]>
To: Tom Belnick <Tom.Belnick(a),ncmail.net>
It does not appear to have any DO issues from 2002-2006 in NC- I do not know about SC. It has a
category 5 listing (303d) for Turbidity
Tom Belnick wrote:
Hey Cam- can you tell me if 12 Mile Creek will be listed as impaired for DO in the 200.8
listing. Union County is requesting another expansion from 6 to 9 MGD, but DWQ has stated
nothing above 6 MGD due to low instream DO. I don't see the stream listed as impaired, and
was wondering why not. Thanks.
Toya Fields
Environmental Engineer
Interbasin Transfer Coordinator
Division of Water Resources
Phone:
Fax:
919 715-0389
919 733-3558
1 of 1 1/21/2009 11:12 AM

?ptfr i l-e /VC008S351
UNION COUNTY
DEPARTMENT OF PUBLIC WORKS
500 North Main Street, Suite 500, Monroe, NC 28112
Phone: [phone] • Fax: [phone]
No+e OrI ,r1p/ 1,c4t sv4,+4,1/u(F"'
April 22, 2014 0g 4°D (e 6ahl on cP lci� 1,v4s c/4
Mr. Tom Belnick cQ1- lie Ca y/ �0 te-.J 4� ('e�lt�✓k
SupervisorSA) A
NPDES Complex Permitting Unit % 5/$�iy / RECEIVED/DENR/DWR
N.C. Department of Environment and Natural Resources
1617 Mail Service Center
Raleigh, NC 27699-1617
RE: Union County Public Works
Twelve Mile Creek'Wastewater Treatment Plant
NPDES Permit Modification, Permit No. NC0085359
Dear Mr. Belnick,
APR 2 5 2014
Water Resources
Permitting Section
030$3g
Cc f awbo
This letter is in regards to a telephone conversation you had with our consultant (Jim
Struve, PE, of Hazen and Sawyer) on Thursday, April 10, 2014 pertaining to additional
information needed to facilitate your review of a permit renewal and major modification of
Union County's Twelve Mile Creek Wastewater Treatment Plant.
This additional information is summarized_ below and appended to this letter where
applicable:
• Priority Pollutant Scan performed by Pace Analytical for sample received on
December 13, 2013. Analytical results are contained in Appendix A.
• Reduction of Monitoring Frequency Analysis technical memorandum prepared by
Mary Sadler, PE, of Hazen and Sawyer dated March 25, 2014. The analysis
demonstrates that the Twelve Mile Creek Wastewater Treatment Plant has met the
requirements to be categorized as an "Exceptionally Performing Facility" per DWR
guidance. The technical memorandum is contained in Appendix B.
• Conversation with Cindy Moore (NCDENR Aquatic Toxicology Unit) on March 31,
2014 regarding second species chronic toxicity tests. Ms. Moore stated that this
test (utilizing fathead minnows) should be conducted in May and August of 2014 in
parallel with the regularly scheduled quarterly chronic toxicity tests (utilizing
ceriodaphnia dubia). Upon receipt of the test results, they will be forwarded
immediately to your attention.
We sincerely appreciate your efforts to expedite the review and subsequent approval of
the County's renewal/major modification permit package. It is our hope and understanding
1 of2 4/22/2014

UNION COUNTY PUBLIC WORKS
that every effort will be made to have a finalized permit by November 1, 2014. If you have
any questions or comments concerning this additional information or information
previously submitted, please do not hesitate to contact us.
Sincerely,
Edward Goscicki, PE
Executive Director
Enclosures:
Appendix A
Appendix B
Cc: Amy Deyton, Union County
Jim Struve, PE, Hazen and Sawyer
RECEIVED/DENR/DWR
APR 2 5 2014
Water Resources
Permitting Section
2 of 2 4/22/2014

6Y ii0eS
UNION COUNTY
DEPARTMENT OF PUBLIC WORKS
500 North Main Street, Suite 500, Monroe, NC 28112
Phone: [phone] • Fax: [phone]
February 11, 2014
Mr. Jeff Poupart
Wastewater Branch Supervisor
N.C. Department of Environment and Natural Resources
Division of Water Resources
1617 Mail Service Center
Raleigh, NC 27699-1617
RE: Union County Public Works
Twelve Mile Creek Wastewater Treatment Plant
NPDES Permit Modification, Permit No. NC0085359
Dear Mr. Poupart,
IA@MIND n11
NF►
1 MAR 1 2 Z014
L.
DEE sii7 1NATth—QU I TY
POINT SOURCE BRANCH
Enclosed are three (3) copies of the NPDES permit modification package for the Union
County Public Works Twelve Mile Creek Wastewater Treatment Plant (WWTP) Expansion
Project. This application is for an expansion of the Twelve Mile Creek WWTP from its
current capacity of 6 million gallons per day (mgd) to an expanded capacity of 12 mgd.
The application package includes the following information:
• Cover letter
• Application fee of $1,030.00
• Completed NPDES Permit Application — Form 2A
• Revised RPA for copper and zinc
• Engineering Alternatives Analysis (EAA)
• Speculative Limits for WWTP Expansion to 12 mgd — Letter provided by the
Division of Water Resources (DWR) on September 1, 2010 (appendix to EAA)
• Finding of No Significant Impact (FONSI) (appendix to EAA)

UNION COUNTY PUBLIC WORKS
The Environmental Assessment (EA) concluded that the most feasible and cost effective
effluent discharge option was the expansion of the effluent discharge into Twelve Mile
Creek. This conclusion was supported by QUAL2E water quality modeling, as documented
in the EA. The FONSI was sent to the Department of Administration (DOA) Environmental
Clearinghouse in September 2013 by the Division of Water Resources (DWR). The project
cleared the DOA on October 17, 2013.
Union County respectfully requests the following changes to the current NPDES permit as
a result of this permit modification for the capacity expansion:
1. The expansion project has been divided into two phases because of Union County's
available funds. The first phase is an expansion from 6 to 9 mgd and the second
phase is an expansion from 9 to 12 mgd. The Speculative Discharge Limits letter
provided anticipated limits for the expanded flow (12 mgd), only. We respectfully
request effluent permit limits for the current flow of 6 mgd and future expanded flows of
9 mgd and 12 mgd.
2. We request a reduction in monitoring frequency for biochemical oxygen demand
(BOD5), total suspended solids (TSS), ammonia, and fecal coliform. Our request is
based on the understanding that the Twelve Mile Creek WWTP has met the monitoring
requirements for categorization as an "exceptional performing" facility. It is our
understanding that DWR requires accelerated monitoring for six months following a
plant expansion. We request that the permit automatically revert to the "exceptional
performing facility" reduced monitoring frequency at the conclusion of the six month
accelerated monitoring period. This is of course dependent upon the Twelve Mile
Creek WWTP continuing to qualify as an "exceptionally performing" facility during that
six-month period.
3. We request that Special Condition A(4) be revised to require three pollutant scans per
permit cycle in lieu of our current permit cycle condition for five pollutant scans.
4. We request that the revised November 2011 standard conditions be attached to our
permit.
5. We request that the effluent limits for copper and zinc be removed from our permit.
Our request is based on the following two observations.
First, copper and zinc are designated as action -level water quality standards in North
Carolina, so permit limits should only be applied if the plant has experienced Whole
2 of 2/17/2014

�.1 `" UNION COUNTY PUBLIC WORKS
vj i )C� (-)%
—w
0-k"" 1-Sb‘°j eX 1 ,
4--e5- '''d r..?‹ 4 i 4. '1-50 t4' JP)( l' ' r.-\'‘' (/ ri-''-A (Iii( F- IIC i
/ \ ' tk'r‘ k i- \ , „.0., ,,,,e,(9- ,.,p‘ v, \()-- g
n \ cN e
.,,/\,:v-i e %oax .,
' el- % -le' 01- k, 'ii‘ /.. ,•(‘3 4.1-f".r-r--, J \'`''
&t, cie s'''' 43
Effluent Toxicity (WET) failures. The Twelve Mile Creek WWfP has not failed any , .
WET tests since 2008. 4 I) 01
Second, a review of the 2005/2006 WER study along with applicable EPA guidance
resulted in updated and increased site -specific criteria for copper and zinc, thus
eliminating the reasonable potential for the discharge to exceed the applicable water
quality criteria. The following paragraphs highlight conclusions associated with the
2005/2006 WER study review.
For copper:
From the WER data, the method outlined in EPA's Streamlined Water -Effect Ratio
Procedure for Discharges of Copper (EPA-822-R-01-005) was used to calculate a
final dissolved WER of 2.786 using the geometric mean of the measured WERs.
Additionally, a site specific translator of 0.778 was derived from the total
recoverable and dissolved measurements. The dissolved WER and site -specific
translator were used to adjust the recommended dissolved copper criteria to
develop a site -specific criteria for the receiving stream as follows:
The recommended national dissolved criteria for copper at a mixed -stream
hardness of 59 mg/L are 5.7 ug/L (CCC) and 8.17 ug/L (CMC).
Site specific CCC (dissolved) = 5.7* (2.786) = 15.89 ug/L Cu
Site specific CCC (total recoverable) = 15.89/0.778 = 20.43 ug/L Cu
Site specific CMC (dissolved) = 8.17* (2.786) = 22.77 ug/L Cu
Site specific CMC (total recoverable) = 22.77/0.778 = 29.26 ug/L Cu
For zinc:
The final dissolved WER for zinc is 2.905 and the site -specific translator is 0.082.
The dissolved WER and site -specific translator were used to adjust the
recommended dissolved zinc criteria to develop a site -specific criteria for the
receiving stream as follows:
The recommended national dissolved criterion for zinc at a mixed -stream hardness
of 59 mg/L is 75.55 ug/L.
Site specific CMC(dissolved) = 75.55 (2.905) = 219.45 ug/L Zn
3 of 4 2/17/2014

UNION COUNTY PUBLIC WORKS
4,0,eo
Site specific CMC (total recoverable) = 219.45/. = 273.70 ug/I
A reasonable potential analysis (RPA) on data from January 8, 2010 through October
30, 2013 does not demonstrate reasonable potential to exceed the site -specific copper
and zinc water quality criteria based on the 2005/2006 WER study. As a result, both
the copper and zinc limits should be removed from the permit.
We appreciate the time and effort of the NPDES Unit to consider our requests for this
permit modification. If you have any questions or comments concerning this permit
modification package, please do not hesitate to contact us.
Sincerely,
Edward Goscicki, PE
Executive Director
Enclosures:
Please see above list.
cc: Amy Deyton, Union County
Jim Struve, P.E., Hazen and Sawyer
4 of 2/17/2014

i
Additional information, if provided, will appear on the following pages.
Form 2A — Part B.3 Attachment (1)
Twelve Mile Creek WWTP, NC0085359
Process narrative
Twelve Mile Creek WWTP Existing 6-mgd Rated Capacity Process Flow
The Twelve Mile Creek WWTP is currently rated to treat up to 6-mgd. Union County is
undergoing planning and preliminary engineering to expand the plant rated capacity to 9-
mgd. Planning will also consider ultimate future expansion to 12-mgd.
Figure 1 provides a schematic of the existing plant unit processes for 6-mgd capacity,
including a water balance through the plant. The following narrative paragraphs
summarize existing unit processes and anticipated modifications to those processes to
expand the plant rated capacity to 9-mgd and then to 12-mgd.
Influent Pumping and Preliminary Treatment
A 48-inch interceptor conveys wastewater to the Twelve Mile Creek WWTP. Influent
wastewater is screened with one mechanical fine screen (1/4-inch spacing). Screened
influent flow is pumped either by the influent pumps (four submersible pumps; 15-mgd
firm capacity) to the treatment plant or by the diversion pumps (two submersible pumps;
2-mgd firm capacity) to McAlpine Creek WWMF (Charlotte Mecklenburg Utility
Department). Flow pumped to the plant is metered and then passed through one stirred
vortex grit removal tank. The influent pumping and preliminary treatment facilities are
designed for a maximum hydraulic flow rate of 15-mgd (2.5 times the plant rated
capacity of 6-mgd).
Plant expansion will increase the hydraulic capacity of influent pumping and preliminary
treatment facilities to 22.5-mgd (2.5 times the expanded plant rated capacity of 9-mgd)
including: addition of coarse screenings; wet well volume for additional 7.5-mgd of
influent pumping capacity; increased flow metering capacity; and, construction of new
fine screen capacity and new grit removal tank capacity.
Another plant expansion will increase the hydraulic capacity of influent pumping and
preliminary treatment facilities to 30-mgd (2.5 times the expanded plant rated capacity of
12-mgd) including: additional coarse screen capacity; wet well volume for additional 7.5-
mgd of influent pumping capacity; increased flow metering capacity; and, construction of
new fine screen capacity and new grit removal tank capacity.
Secondary Treatment
Preliminary treatment effluent is hydraulically distributed to four fermentation-anoxic-
oxic (FAO) basins. The FAO basins provide biological phosphorus removal and
nitrification. Mechanical aerators are used for oxidation. FAO basin effluent is
hydraulically distributed to four secondary clarifiers (two, 70-foot diameter and two, 85-
foot diameter). A dedicated return activated sludge (RAS) pump is provided for each
clarifier. Combined RAS is blended with preliminary treatment effluent upstream of FAO
basin distribution. Chemical storage and feed facilities provide alkalinity control and
additional phosphorus removal.
Plant expansion will increase the secondary process to 9-mgd rated capacity, with 22.5-
mgd peak flow rate, including: increased piping capacity for higher flow rates;
conversion of mechanically aerated oxidation ditches to plug flow reactors with diffused
NPDES FORM 2A Additional information

Additional information, if provided, will appear on the following pages.
aeration and installation of aeration blowers; and, construction of an additional secondary
clarifier with associated RAS pumping.
Another plant expansion will increase the secondary process to 12-mgd rated capacity,
with 30-mgd peak flow rate, including: increased piping capacity for higher flow rates;
construction of additional aeration basin capacity with associated blower, air piping, and
diffusers; and, construction of an additional secondary clarifier with associated RAS
pumping.
Tertiary Treatment
Secondary treated effluent is conveyed to four travelling hood filters. Filtered flow is
disinfected in two medium -pressure / high -intensity ultraviolet (UV) disinfection
channels. Disinfected flow is re -aerated in a cascade aerator prior to discharge at the
Twelve Mile Creek effluent outfall.
Plant expansion will increase the tertiary process to 9-mgd rated capacity, with 22.5-mgd
peak flow rate, including: expansion of filters, UV disinfection, and cascade aeration with
additional units equivalent to existing; and, increased process piping and effluent outfall
capacity for higher flow rates.
Another plant expansion will increase the tertiary process to 12-mgd rated capacity, with
30-mgd peak flow rate, including: expansion of filters, UV disinfection, and cascade
aeration, and, increased process piping and effluent outfall capacity for higher flow rates.
An alternate tertiary process modification to be evaluated is to construct new deep -bed
filters for future process flexibility (in lieu of additional travelling hood filters).
Solids Handling and Treatment
Waste activated sludge (WAS) is removed from the biological process from a single
waste point off the combined RAS manifold. WAS is conveyed to the solids handling and
treatment area by a booster pump with a modulating control valve. WAS is thickened by
one gravity belt thickener. Thickened WAS is aerobically digested in four aerobic
digester tanks (two, 0.25-MG tanks and two, 1.00-MG tanks). The aerobic digesters are
provided with coarse bubble diffusers, with air supplied by eight positive -displacement
blowers. Digested solids meeting Class B requirements are land applied off -site on
permitted agricultural farmland.
Plant expansion will increase the capacity to treat the additional solids that will be
generated with expanding the secondary treatment process, including: additional solids
handling equipment and additional digester volume for 9-mgd rated capacity and then for
12-mgd.
Twelve Mile Creek WWTP Expanded 9-mgd Rated Capacity Process Flow
Figure 2 provides a schematic of the plant unit processes for an expanded rated capacity
of 9-mgd including a water balance through the plant.
Twelve Mile Creek WWTP Expanded 12-mgd Rated Capacity Process Flow
Figure 3 provides a schematic of the plant unit processes for an expanded rated capacity
of 12-mgd including a water balance through the plant.
NPDES FORM 2A Additional Information

Legend:
FBW = Filter Backwash
FM = Force Main
RAS = Return Activated Sludge
WAS = Waste Activated Sludge
FAO = Fermentation-Anoxic-Oxic
MLSS = Mixed Liquor Suspended Solids
GBT = Gravity Belt Thickener
Orange Text = Flows at 6-mgd Plant Design Capacity
Fine
Screens
To
McAlpine 18» FM
Creek ill
WWMF
(CMU)
Diversion
Pump Station
To Land
Application
Q=0.74 mgd
Twelve
Mile Creek
Aerobic
Digestion
Cascade
Aerator
Q=6.0 mgd
Influent
Pump Station
Sludge
Transfer
Station
UV Disinfection
Supernatant
Sludge
Holding
Tank
Grit
Removal
Grit
Q=12.0 mgd
FAO
Distribution Box
Tertiary
Filters
In -Plant
Pump Station
GBT
Polymer WAS
Pump Station
FAO Basins
RAS
�— Q=6.0mgd
MLSS
Distribution
Box
Secondary
Clarifiers
— Q=6.0 mgc.
RAS
Pump Station
f- Q=0.5 mgd
Q=6.5 mgd
Figure 1
WWTP Process Flow Diagram for 6 mgd
Union County, NC
Twelve Mile Creek WWTP
NC0085359
B.3 of Form 2A
30831-030-002 Figure 2A.cdr

Legend:
FBW = Filter Backwash
FM = Force Main
RAS = Return Activated Sludge
WAS = Waste Activated Sludge
FAO = Fermentation-Anoxic-Oxic
MLSS = Mixed Liquor Suspended Solids
GBT = Gravity Belt Thickener
Orange Text = Flows at 9-mgd Plant Design Capacity
Coarse
Screens
To
McAlpine 18" FM
Creek 1
WWMF
(CMU)
Q=9.0 mgd
Influent
Pump Station
Q=1.11 mgd
Diversion
Pump Station
Twelve
Mile Creek
To Land
Application
Fine
Screens
Cascade
Aerator
04-
Aerobic
Digestion
UV Disinfection
Supernatant
Grit
Removal
Grit
Aeration Basin
Distribution Box
•
Tertiary
Filters
FBW
In -Plant
Pump Station
Sludge
Transfer
Station
Sludge
Holding
Tank
Polymer WAS
Pump Station
SAM
I_O
GBT
'
Q=18.0 mgd
Aeration Basins
RAS
—.— Q=9.0mgd
MLSS
Distribution
Box
Secondary
Clarifiers
—Q=9.Omer
RAS
Pump Station
1.1
-.IF— Q=0.75 mgd
Q=9.75 mgd
Figure 2
WWTP Process Flow Diagram for 9 mgd
Union County, NC
Twelve Mile Creek WWTP
NC0085359
B.3 of Form 2A
30831.030.002 Figure 2B.cdr

Legend:
FBW = Filter Backwash
FM = Force Main
RAS = Return Activated Sludge
WAS = Waste Activated Sludge
FAO = Fermentation-Anoxic-Oxic
MLSS = Mixed Liquor Suspended Solids
GBT = Gravity Belt Thickener
Coarse
Screens
To
McAlpine 18" FM
Creek 4
WWMF
(CMU)
4
Diversion
Pump Station
Influent
Pump Station
Q=1.48 mgd
Twelve
Mile Creek
171
Orange Text = Flows at 12-mgd Plant Design Capacity
Q=12.0 mgd
Fine
Screens
Cascade
Aerator
Sludge
Digestion Transfer
To Land Station
Application
UV Disinfection
Supernatant
Sludge
Holding
Tank
Grit
Removal
Grit
Q=24.0 mgd
Aeration Basin
Distribution Box
Tertiary
Filters
In -Plant
Pump Station
GBT
Polymer WAS
Pump Station
Aeration Basins
RAS
-NI— Q=12.0 mgd
MLSS
Distribution
Box
4
Secondary 4
1 Clarifiers
L
RAS
Pump Station
- — Q=1.0 mgd
Q=13.0 mgd
Figure 3
WWTP Process Flow Diagram for 12 mgd
Union County, NC
Twelve Mile Creek WWTP
NC0085359
B.3 of Form 2A
30831-030-002 Figure 2C.cdr

Additional information, if provided, will appear on the following pages.
Form 2A — Part B.4 Attachment (2)
Twelve Mile Creek WWTP, NC0085359
Name: Charlotte Mecklenburg Utility Department
Mailing Address: Environmental Services Facility —4222 Westmont Drive
Charlotte, NC 28217
Telephone Number: [phone]
Responsibilities of Contractor: Performing contract operations at the plant, including
providing staffing for operations and maintenance.
NPDES FORM 2A Additional Information

lditional information, if provided, will appear on the following pages.
Form 2A — Part B.5 Attachment (3)
Twelve Mile Creek WWTP, NC0085359
The schedule for completion of the plant expansion to 9-mgd is approximately as
follows:
• Finalize preliminary engineering report (PER) for 9-mgd expansion — 07/2014
• Complete detailed design for 9-mgd expansion — 07/2015
• Complete construction for 9-mgd expansion — 01/2018
The schedule for completion of the plant expansion to 12- mgd is approximately as
follows:
• Finalize preliminary engineering report (PER) for 12-mgd expansion — 03/2026
• Complete detailed design for 12-mgd expansion — 03/2027
• Complete construction for 12-mgd expansion — 09/2029
See Part B.3 Attachment (1) for descriptions of the 9-mgd and 12-mgd expansion
improvements.
NPDES FORM 2A Additional Information

F WI/ Perini' eenewnt
Belnick, Tom
From: Belnick, Tom
Sent: Thursday, March 13, 2014 11:49 AM
To: '[e-mail]'; '[e-mail]'
Cc: Moore, Cindy
Subject: NPDES Union County 12 Mile WWTP
Permit File: NC0085359, Union County/12 Mile WWTP
Major Mod (Expansion) + Renewal
Jim/Ed- per discussion with Jim yesterday, I'm following up with some additional info on your NPDES Modification
request. Since we are approaching the expiration date of your NPDES permit for 12 Mile Creek WWTP (expires
6/30/2015, renewal app due a minimum of 6 months prior), I plan to combine your request for Major Mod expansion
(from 6 MGD to 12 MGD) together with a permit renewal. Thus, I will need some additional information to complete the
renewal application.
1. Second Species Toxicity Tests. Please verify with Cindy Moore of our Aquatic Toxicology Unit (copied, 919/743-
8442) that your EPA Form 2A/Part E Toxicity Test submittal fulfills the EPA requirement for four (4) second
species toxicity tests with application. NPDES relies upon Cindy's Unit to evaluate this toxicity data.
2. Priority Pollutant Analyses. Include results of the 3 Priority Pollutant Analyses conducted over the current
permit term.
3. Monitoring Frequency Reduction (MFR)/Supporting Material. You made a request for Monitoring Frequency
Reduction based on performance. You will need to submit additional information to support this request. Refer
to the following link: http://portal.ncdenr.org/c/document library/get file?uuid=90fdd082-6172-42c0-b4ee-
cf3968502019&groupld=38364. You posed a question about how the MFR will play out with the expansion, and
we will look at that during renewal development. At a minimum, if you meet the criteria, MFR will be
incorporated into the current 6 MGD effluent sheet.
That's all I can think of at this point. I don't recall if you have any SlUs, which would require Part F of EPA Form 2A to be
completed. By combining renewal with modification, we will only need to conduct one 30-day public notice and one EPA
review, and you will not have to resubmit a separate permit renewal in early 2015. Let me know if any questions. I
indicated I would get back to Jim in April to let him know our schedule (how soon we can get to this), as well as yours.
Tom Belnick
Supervisor, NPDES Complex Permitting Unit
NCDWR/Water Quality Programs
919-807-6390
E-mail correspondence to and from this address may be subject to the
North Carolina Public Records Law and may be disclosed to third parties r� �e /
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Belnick, Tom
From:
Sent:
To:
Cc:
Subject:
Moore, Cindy
Thursday, March 13, 2014 1:36 PM
[e-mail]; [e-mail].0
Belnick, Tom; Reid, Dianne
RE: NPDES Union County 12 Mile WWTP
I'll be glad to answer any questions that you may have. Briefly, your permit stipulates that you test for Ceriodaphnia
dubia in the month of Feb, May August and November. Per EPA requirements, the facility should start testing a year in
advance of renewal with a second species organism, that being Pimephales promelas ( fathead minnows). This second
species testing should be done in conjunction with your regular Ceriodaphnia test. Please give me a call if you have
questions, 919-743-8442.
Thanks
Cindy
From: Belnick, Tom
Sent: Thursday, March 13, 2014 11:49 AM
To: [e-mail]; edward.goscickKKco.union.nc.us
Cc: Moore, Cindy
Subject: NPDES Union County 12 Mile WWTP
y/,o/,Y- PIN 114 4111CWJ.l, w/
iAi S¢(WV( /14 •-JAi it/ (41 fr1
Permit File: NC0085359, Union County/12 Mile WWTP
Major Mod (Expansion) + Renewal
7041&intc/L
Jim/Ed- per discussion with Jim yesterday, I'm following up with some additional info on your NPDES Modification
request. Since we are approaching the expiration date of your NPDES permit for 12 Mile Creek WWTP (expires
6/30/2015, renewal app due a minimum of 6 months prior), I plan to combine your request for Major Mod expansion
(from 6 MGD to 12 MGD) together with a permit renewal. Thus, I will need some additional information to complete the
renewal application.
mod) N
vIIt �t � A.)LL
re (nit iip/i,cA
1. Second Species Toxicity Tests. Please verify with Cindy Moore of our Aquatic Toxicology Unit (copied, 919/743-
8442) that your EPA Form 2A/Part E Toxicity Test submittal fulfills the EPA requirement for four (4) second
species toxicity tests with application. NPDES relies upon Cindy's Unit to evaluate this toxicity data.
2. Priority Pollutant Analyses. Include results of the 3 Priority Pollutant Analyses conducted over the current
permit term.
3. Monitoring Frequency Reduction (MFR)/Supporting Material. You made a request for Monitoring Frequency
Reduction based on performance. You will need to submit additional information to support this request. Refer
to the following link: http://portal.ncdenr.org/c/document library/get file?uuid=90fdd082-6172-42c0-b4ee-
cf3968502019&groupld=38364. You posed a question about how the MFR will play out with the expansion, and
we will look at that during renewal development. At a minimum, if you meet the criteria, MFR will be
incorporated into the current 6 MGD effluent sheet.
That's all I can think of at this point. I don't recall if you have any Sills, which would require Part F of EPA Form 2A to be
completed. By combining renewal with modification, we will only need to conduct one 30-day public notice and one EPA
review, and you will not have to resubmit a separate permit renewal in early 2015. Let me know if any questions. I
indicated I would get back to Jim in April to let him know our schedule (how soon we can get to this), as well as yours.
Tom Belnick
Supervisor, NPDES Complex Permitting Unit

NCDWR/Water Quality Programs
919-807-6390
E-mail correspondence to and from this address may be subject to the
North Carolina Public Records Law and may be disclosed to third parties