NC0028916_NPDES Draft Permit_20090826

A7A
NCDENR
North Carolina Department of Environment and Natural Resources
Division of Water Quality
Beverly Eaves Perdue Coleen H. Sullins
Governor Director
August 26, 2009
Mr. Gray Wells, Public Services Director
Town of Troy
315 N. Main Street
Troy, North Carolina 27371-7841
Subject: Draft NPDES PermitNC0028916
Troy WWTP
Montgomery County
Dear Mr. Wells:
Dee Freeman
Secretary
Enclosed with this letter is a copy of the draft permit for your facility. Please review the draft carefully to ensure a thorough
understanding of the conditions and requirements it contains.
This Draft permit contains the following changes from your existing permit:
1. The 2/month monitoring requirement for arsenic has been deleted, and
2. The 2/month monitoring requirement for chlorides has been deleted.
Concurrent with this transmittal, the Division will solicit public comment on this draft as required by the EPA by publishing a,
notice in newspapers having circulation in the general Montgomery County area. Should you wish to correct errors or provide
comments regarding this draft please contact the DENR / DWQ / NPDES Program no later than 30 days after receiving this
document.
Following the 30-day public comment period, the Division will review all pertinent comments and take appropriate action prior to
issuing a final NPDES permit. If you have questions concerning the draft permit for your facility, please contact me by e-mail
([e-mail]) or call me at [phone].
Respectfully,
Robert L. Guerra
NPDES Unit, Western Program
Enclosure: NPDES Permit NCO28916 (DRAFT)
cc: NPDES Unit
Fayetteville Regional Office / Surface Water Protection [e-mail]) (ecopy)
Aquatic Toxicology Unit — Susan Meadows ([e-mail] (ecopy)
Technical and Assistance Certification Unit — Steve Reid ([e-mail]) (ecopy)
EPA Region 4
Marshall Hyatt ([e-mail])
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.ncwaterquafity.org
An Equal Opportunity \ Affirmative Action Employer
NorthCarolina
Naturally

Permit NC0028916
STATE OF NORTH CAROLINA
DEPARTMENT OF ENVIRONMENT AND NATURAL RESOURCES
DIVISION OF WATER QUALITY
PERMIT
TO DISCHARGE WASTEWATER UNDER THE
NATIONAL POLLUTANT DISCHARGE ELIMINATION SYSTEM
In compliance with the provisions 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,
\\Town ofTroy
l
g orized to d scli r e
�a
Ater f om a facility located at the
TrOy Wa\stewater-fie tm a -Plant
Off/NCSR 134
Troy
Flo t oniery Cob ty
v I
to receiving waters designated as Densons Creek in the Yadkin -Pee Dee 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 xxxx, xx 2009.
This permit and authorization to discharge shall expire at midnight on June 30, 2014.
Signed this day xxxx,xx 2009.
DRAFT
Coleen H. Sullens, Director
Division of Water Quality
By Authority of the Environmental Management Commission

- PermitNC0028916
SUPPLEMENT TO PERMIT COVER SHEET
All previous NPDES Permits issued to this facility, whether for operation or discharge are hereby
revoked. As of this permit issuance, any previously issued permit bearing this numberis 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.
Town of Troy is hereby authorized to:
1. Continue to operate an existing 1.2 MGD wastewaters treatment. plant consisting of the
following treatment components:
• Flow equalization
• 10-Acre EQ Basin
• Mechanically cleaned bar screen
• Aerated grit chamber
• Grit removal system
• Influent Parshall Flume with Ultrasonic flow meter
• Dual oxidation ditches arranged in series
• Dual secondary clarifiers
• UV disinfection
• Chlorination/dechlorination (back-up)
• Sludge transfer tank
• Aerobic sludge digester
This facility is located at the Troy Wastewater Treatment Plant, 650 Glen Road, Troy,
Montgomery County.
2. Discharge from said treatment works at the location specified on the attached map into
Densons Creek, classified C waters in the Yadkin -Pee Dee River Basin.

Permit NC0028916
A. (1.) EFFLUENT LIMITATIONS AND MONITORING REQUIREMENTS
During the period beginning on the effective date of this permit and lasting until expiration, the Permittee is
authorized to discharge from outfall 001. Such discharges shall be limited and monitored by the Permittee as
specified below:
EFFLUENT
CHARACTERISTICS
LIMITS
MONITORING REQUIREMENTS
Monthly
Average
Weekly
Average
Daily
Maximum
Measurement
Frequency
Sample
Type
Sample
Location:
50050 - Flow
1.2 MGD
Continuous
Recording
I or E
00010 - Temperature (°C)
Daily
Grab
E
00310 - BOD, 5-day, 20° C`
(April 1-October 31)
7.0 mg/L
10.5 mg/L
3/Week
Composite
E,I
00310 - BOD, 5-day, 20° C`
(November 1-March 31)
14.0 mg/L
21.0 mg/L
3/Week
Composite
E,I
00530 - Total Suspended
Solids2
30.0 mg/L
45.0 mg/L
3/Week
Composite
E,I
00610 - NH3 as N
(April 1 — October 31)
2.0 mg/L
6.0 mg/L
3/Week
Composite
E
00610 - NH3 as N
(November 1 — March 31)---N,
4.0
mg/L
12.0 mg/L
3/Week
Composite
E
`�\
/
;
—1 I
I
00300 - DissolvedlOxygen°'4 \
1
\
/ \
3/Week
I (Grab
IE, U, D
31616 - Fecal Colifor
(geometric mean)—�\
200/100 rrnL,,400/1100m1
\ 1
i I
,
3iW ek
) LGrab
E
50060 - Total Residua
Chlorine°
\ 11
I
/ 20\pg/L
3/W,eek
Grab I
E
00010 - Temperature (°C)d
\
I 1 1
/ I
/ \ \
13/W;eek
Grab 1
U,D
00094 - Conductiv)tyd
1
I 1 1
----/ / /
/ \ 1
0/ A/
1 Grab 1
E,U,D
00400 - pH 1
1 1
1 1 6.0 — 9.0 Standard/Unit's 1 1,
!3/Week
Grab 1
E
01092 Total Zinc
I
F\
C
\
/ % l
nth
1 Composite•E
2/M i
1
01042 Total Copjaer
II
'
\ /
\ /
1
>z/Month
Composite
E
00600 - Total Nitrdgenl
(NO2+NO3+TKN) I
--/
i
I
\ \\
\ , /
\
/ \
1 IMo 'thly
\
Composite
E
/
00665 - Total Phosphorus
/
\ `\' /
Monthly
Composite
E
Chronic Toxicity°
Quarterly
Composite
E
Pollutant Analysis'
Annually
Composite
E
Footnotes:
1. Sample locations:. E-Effluent, I -Influent, U-Upstream at least 100 feet, D-Downstream approximately 0.4 miles before the
confluence with Spencer Branch.
2. The monthly average effluent BOD5 and Total Suspended Solids concentrations shall not exceed 15 percent of the respective
monthly average influent value (85% removal).
3. Stream samples shall be grab samples and shall be collected 3/Week June -September and 1/Week during the remaining months
of the year.
4. The daily average dissolved oxygen concentration in the effluent shall not fall below 5.0 mg/L.
5. TRC monitoring and effluent limitations apply only if chlorine is added to disinfect.
6. Chronic Toxicity (Ceriodaphnia dubia) P/F at 84%: January, April, July, and October (see Part I, A (2.)). Toxicity monitoring shall
coincide with metals monitoring.
7. See Condition A. (3.) of this permit.
There shall be no discharge of floating solids or visible foam in other than trace amounts.

Permit NC0028916
A. (2.) CHRONIC TOXICITY PERMIT LIMIT (QRTRLY) -1.2 MGD
The effluent discharge shall at no time exhibit observable inhibition of reproduction or significant mortality to
Ceriodaphnia dubia at an effluent concentration of 84%.
The permit holder shall perform at a minimum, quarterly monitoring using test procedures outlined in the "North
Carolina Ceriodaphnia Chronic Effluent Bioassay Procedure," Revised February 1998, or subsequent versions or
"North Carolina Phase II Chronic Whole Effluent Toxicity Test Procedure" (Revised -February 1998) or
subsequent versions. The tests will be performed during the months of January, April, July and October.
Effluent sampling for this testing 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 -February 1998) 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--998) or subsequent -versions.
I
All toxicity testing results regiiiired as part of4his ciermit cpQnditioh will be entered-on-th -Effluent Discharge
Monitoring Forrin (MR-1) for the months in which tests were performed, Lasing the parameter code TGP3B for the
pass/fail results and THP3B for the Chronic Value. Addjtior7ally,\pWQ Form AT-3 (original) is to be sent to the
following address: !!
Attention: North'Caroliria Division of Wa er Quality
Env ronmental Sciences\Sect on
\1621 Mail Service Center
Rale gh, North Carolina \276 9- 621
Completed Aquatic T-M c ty Test Forms shall be tiled wi'h the Erivirohm ntal Sciences Section no later than 30
days after the end of the re -orting period for \hic which eport is read
Test data shall be complete, accurate, include all supporting chemical/phys.cal 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 Environmental 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.
Should any test data from this monitoring requirement or tests performed by the North Carolina Division of Water
Quality 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.

Permit NC0028916
A. (3.) PRIORITY POLLUTANT ANALYSIS (PPA)
The Permittee shall perform an annual Priority Pollutant Analysis for all parameters listed in the attached table.
The 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 shall represent seasonal variations. 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
Nickel
Selenium
Silver
Thallium
Zinc
Cyanide
Total phenolic compounds
Volatile organic compounds:
Acrolein
Acrylonitrile
Benzene
Bromoform
Carbon tetrachloride
Chlorobenzene
Chlorodibrofnomethan�
Chloroethane
2-chloroeth
Chloroform
Dichlorobro
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-trich loroethane
1,1,2-trichloroethane
Trichloroethylene
Vinyl chloride.
Acid -extractable compounds:
P-chloro-m-cresol
2-chlorophenol
2,4-dichlorophenol
2,4-dimethylphenol
4, 6-d i n itro-o-creso l
2,4-dinitrophenol
2-nitrophenol
4-nitrophenol
Pentachlorophenol
Phenol
2,4,6-trichlorophenol
Base -neutral compounds:
Acenaphthene
• Acenaphthylene
�Anthracene
Benzidine
Benzo()anthraeene
Bernzo(a pyrene/ ,
3,4 qen fluor nthene
Benzo(g i)per len ' \
1,1-dichlordethane , Benzo(I�)fluordnth ne
1,2-dichlor�ethane Bis�dhloro�4hoxy) ethane
Test results shall be reported o tile Division Dv1(Q ForM- A DMR-P A1
Director, within 90 ay of sampling. A copy of the\report shall be subrnitte
Division of Water uality, Water / ual ty ectio , 1 17 Mail Service-Ce ter,
27699-1617 /
/ \' \ / \
Ivi�yl liter
nometha e
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)anthracene
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
Indeno(1,2,3-cd)pyrene
Isophorone
Naphthalene
Nitrobenzene
_atroso_di.n-ptopyiam ine
N-n itrosod im ehylam ine
N-nitrosodipi ,nylamine
Phenanthrene
Pyrene
1,2i4-trichlorobenzene
r in a form approved by the
I to the following address:
Raleigh, North Carolina

DENR/DWQ
FACT SHEET FOR NPDES PERMIT DEVELOPMENT
NPDES No. NC0028916
Facility Information
Applicant/Facility Name:
Town of Troy WWTP
Applicant Address:
444 North Main Street, Troy, NC 27371
Facility Address:
650 Glen Road, Troy, NC
Permitted Flow
1.2 MGD
Type of Waste:
Domestic and industrial with pretreatment program
Facility/Permit Status:
Class III /Active; Renewal
County:
Montgomery County
Miscellaneous
Receiving Stream:
Densons Creek
Regional Office:
Fayetteville (FRO)
Stream Classification:
C
State Grid / USGS Quad:
Star
303(d) Listed?
No
Permit Writer:
Bob Guerra
Subbasin:
03-07-15
Date:
August 26, 2009
Drainage Area (mi`):
32
Long. 79° 51' 33" W
s7Q10 (cfs)
0.35
•
Lat. 35° 22' 25" N
w7Q10 (cfs) .
2.42
Average Flow (cfs):
32
IWC (%):
84% @ 1.2 MGD
BACKGROUND
The Town of Troy has requested renewal of its NPDES permit NC0028916 which has a design
flow of 1.2 MGD. The plant serves approximately 4,100 persons in the Town of Troy and
discharges into Densons Creek, class C water, in the Yadkin Pee -Dee River Basin. The Town
also has a Water Quality Permit, WQ0001240 which authorizes the Land Application of the
WWTP sludge.
The Town has one non -categorical SIU, Capel Rugs, Inc. which manufactures and dyes
braided rugs. The Town of Troy currently has an active compliant pretreatment program with a
Short Term Monitoring Plan.
RECEIVING STREAM INFORMATION
This facility is located in Subbasin 03-07-15 and discharges to Densons Creek, classified C
waters in the Yadkin Pee -Dee River Basin. The receiving stream is not listed on the 2006
303(d) list as impaired, and the basin plan does not outline any special management strategy
for this creek. Troy is not a member of the Yadkin -Pee Dee River Coalition.
DMR DATA (2004-2009)
DMR data from August 2004 through May 2009 was reviewed. Monthly and weekly averages
for conventional parameters are summarized below.
PERMIT LIMIT COMPLIANCE
The facility has demonstrated consistent compliance in meeting its permit limits and has
received three (3) NOV's in April 2006.
TOXICITY TESTING
Current requirement: Chronic P/F @ 84% 1.2 MGD.
Recommended requirement: Chronic P/F @ 84%.
The facility has been in compliance with its toxicity limit during this permit cycle.
Fact Sheet
NPDES NC0028916 Renewal
Page 1

Effluent Characteristics
Sampling data reported
Monthly Average
Weekly Average
Flow
0.44 MGD
N/A
Summer BOD, 5-day, 20° C (April 1-
October 31)
2.23 mg/L
2.10 mg/L
Winter BOD, 5-day, 20° C (November
1-March 31)
1.65 mg/L
2.38 mg/L
Total Suspended Solids
4.22 mg/L
4.18 mg/L
Summer NH3 as N (April 1 — October
31)
0.15 mg/L
0.12 mg/L
Winter NH3 as N (November 1 — March
31)
0.13 mg/L
0.14 mg/L
Fecal Coliform (geometric mean)
16.75 #/100ml
22.34 #100/ml
Total Residual Chlorine
Ultra violet disinfect'on utilized no TRC
sampling required
This facility also collects data for totalnitrogen, total phosphorus, temperature (effluent and,
Instream) conductivity, pH, dissolved oxygen TRC (when chlorine is utilized for disinfection) and
annual PPA. .
CORRESPONDENCE FILES (2002-2003)
The Fayetteville Regional Office (FRO) has conducted five (5) Compliance and five (5) —
Pretreatment inspections since the existing permit was issued'on August 1, 2004. These
inspections have found the facility to be in compliance with a few "Areas of Concern"' noted.
INSTREAM MONITORING
Upstream Site: At least 100 feet above the outfall; Downstream site: Approx. 0.4 miles before
the confluence with Spencer Branch. A review of instream data showed that DO values are
generally well above the water quality standard of'5 mg/I upstream and downstream of the Troy
WWTP. It is recommended that instream monitoring be continued at the existing frequency.
REASONABLE POTENTIAL ANALYSIS (RPA)
The Division conducted EPA -recommended analyses to determine the reasonable potential for
toxicants to be discharged by this facility, based on DMR and pretreatment data from May 2006
- May 2009. Calculations included parameters listed in the previous permit and pre-treatment
documents to include: arsenic, copper, chlorides and zinc. Results suggest no reasonable
potential for the facility to discharge arsenic and chloride at levels greater than the allowable
concentration. Copper and zinc were predicted at concentrations higher than the allowable;
however these two are action level parameters and limits are not commonly given unless they
are triggered under the Action Level Policy. These will continue to be monitored, but not limited
in the renewal. The facility will still be required to monitor for arsenic and chlorides through the
Pretreatment Short Term Monitoring Plan (STMP). Data from all other toxicants currently
monitored through the STMP was examined and showed no reasonable potential to violate
water quality standards. These will continue to be monitored through the STMP. In addition
Priority Pollutant Analysis sampling data from 2004 — 2009 was submitted and reviewed
Fact Sheet
NPDES NC0028916 Renewal
Page 2

SUMMARY OF PROPOSED CHANGES
In keeping with Division policies, the following changes will be incorporated into the permit:
• Elimination of the arsenic monitoring requirement.
• Elimination of the chloride monitoring requirement.
PROPOSED SCHEDULE FOR PERMIT ISSUANCE
Draft Permit to Public Notice: August 26, 2009
Permit Scheduled to Issue: October 15, 2009
NPDES DIVISION CONTACT
If you have questions regarding any of the above information or on the attached permit, please
contact Bob Guerra at [phone] or by email at [e-mail].
NAME: DATE:
Regional Office Comments
NAME: DATE:
SUPERVISOR: DATE:
Fact Sheet
NPDES NC0028916 Renewal
Page�3