NC0020761_speculative limits_19981216

State of North Carolina Ywamh WA
Department of Environment
and Natural Resources
Division of Water Quality 1 �
Am;± W
James B. Hunt, Governor NCDENR
Wayne McDevitttt,, Secretary
A. Preston Howard Jr. P.E. Director NORTH CAROLINA DEPARTMENT OF
> > > ENVIRONMENT AND NATURAL RESOURCES
December 16, 1998
Ms. Julie Page. Town Manager
Town of Wilkesboro
Post Office Box 1056
203 West Main Street
Wilkesboro, North Carolina 28967
Subject: Speculative Limits Request
Wilkesboro\tt XVTP
NCO021717
Wilkes County
Dear Ms. Page:
On November 9, 1998, the Division received. on your behalf, a request for speculative
effluent limitations from Mr. Michael T. Wiley, P.E., P.S. of Dewberry and Davis for the above
referenced facility. Specifically, speculative limits were requested for flows ranging from 5.0 MGD to
10.0 MGD.
Based on available information the tentative effluent limitations for conventional constituents
at the indicated flows are:
."�_ '"";r�:� n.•9�mer�" a Winter-�k �'Sumltier so-.��Wmter.-�;,-; �.Summer:�,"T�:.Winter.�,-';t
BOD (m�gw/L/r) 30 30 30 30 30 30
NHs-N( L) 21 Monitor 14 Monitor 11 Monitor
TSS (mg/L) 30 30 30 30 30 30
Fecal(#/100 nil) 200 200 200 200 200 200
pH(SU) 6-9 6.9 6.9 6.9 6.9 6.9
TRC(µg/L) 28 28 28 28 28 28
Under Current Division policy, effluent residual chlorine limits and dechlorination facilities
are required for all new or expanding discharges proposing the use of chlorine for disinfection.
Should an alternate form of disinfection be employed, such as ultraviolet light. the chlorine limitation
and associated monitoring will be waived. _
The instream waste concentration at 5.0 MGD is 3.8%, at 7.5 MGD it is 5.6% and at 10.0
MGD it is 7.3%. A chronic toxicity testing requirement with quarterly monitoring will remain a
condition of the NPDES permit. A complete evaluation of limits and monitoring requirements for
metals and other toxicants will have to be addressed at the time a formal NPDES application for
expansion is received. -
P.O. Box 29535.RALEIGH, NORTH CAROLINA 27626-0535 TELEPHONE [phone]/FAX [phone]
AN EQUAL OPPORTUNITY AFFIRMATIVE ACTION EMPLOYER 50%RECYCLED/10%POST-CONSUMER PAPER

Please be aware that you will have to evaluate this project for environmental impacts before
receiving a modified permit. Anyone proposing to construct new or expanded waste treatment
facilities using public funds or public (state) lands must first prepare an environmental assessment
(EA) when wastewater flows (1) equal or exceed 0.5 MGD or (2) exceed one-third of the 7Q10 flow of
the receiving stream. DWQ will not accept a permit application for a project requiring an
environmental assessment until the Division has approved the EA and sent a Finding of No Significant
Impact (FONSI) to the state Clearinghouse for review and comment.
An Environmental Assessment should contain a clear justification for the proposed project. It
should provide an analysis of potential alternatives, including a thorough evaluation of non-discharge
alternatives. Nondischarge alternatives or alternatives to expansion, such as spray irrigation, water
conservation, or inflow and infiltration reduction, are considered to be environmentally preferable to a
surface water discharge. In accordance with the North Carolina General Statutes, the preferred
alternative must be the practicable waste treatment and disposal alternative with the least adverse
impact on the environment. If the EA demonstrates that the project may result in a significant
adverse effect on the quality of the environment, you must then prepare an Environmental Impact
Statement. Gloria Putnam of the Water Quality Planning Branch can provide further information
regarding the requirements of the N.C. Environmental Policy Act. You can contact Ms. Putnam
directly at [phone]. ext. 567.
During the next five years, the Division will be developing a nutrient management strategy for
those facilities in the Yadkin discharging into the High Rock Lake watershed. Effluent limitations for
nitrogen and phosphorus may be imposed as conditions of this strategy. The Division will contact the
Town should it be effected by this strategy.
If you have any questions or comments regarding these speculative limitations, please do not
hesitate to contact Mr. Mark McIntire at telephone number [phone]. extension 553.
Sincerely k Y l/
V,,
��David A. Goodrich
NPDES Supervisor
Cc: Central Files
NPDES Permit File'
Winston-Salem Regional Office, Water Quality

Dewberry & Davis E,�,,,ee Consulting Lexington
F larmrrrs 600 Lesin3tnn Ave.lh�r..
Surveyor. Charlotte.NC 28203
704 342-0,101
Fax [phone]
November 4, 1998
Mr. David A. Goodrich
Supervisor NPDES Unit
NC Department of Environment and Natural Resources
Division of Water Quality
P.O. Box 29535
Raleigh, North Carolina 27626-0535
Reference: Town of Wilkesboro
Wilkesboro 201 Facilities Plan
Dewberry & Davis Project No. C7183
Dear Mr. Goodrich:
w
-n
We have enclosed a copy of a recent plan showing the location of the Town of Wilkesboror"n
existing wastewater treatment plant (WWTP). On behalf of the Town of Wilkesboro, we are
g speculative
requesting s lative effluent limits to accommodate this WWTP. '+
q P
We are exploring an expansion for the WWTP on the order of 5MGD to 10 MGD, from the current TT
allocation of 1 MGD. Although we are not yet certain of the anticipated flow at year 20 of-:the
study, we expect it will fall within the 5-10 MGD range.
Speculative limits were requested for the Town's plant in 1994 for 7.5 MGD and 10 MGD. For
your convenience, copies of letters dated June 6, 1994, and January 6, 1995, respectively are
enclosed. It is our understanding that the subsequent study of the Yadkin River Basin may impact
these limits.
If you have any questions, or require additional information, please call Birk Ayer or me at (704)
342-0401. Thank you for your attention to this matter.
Sincerely,
DEWBERRY & DAVIS
Michael T. Wiley, P.E., P.S.
Senior Project Manager
MTW/mtw SAPR0JECTS\C7183\C0RRESP\112LTRl.DOC
c: Julie Page—Town of Wilkesboro
Birk Ayer, P.E. —D&D
Virginia Maryl:wd NmtL Carolina California Georgia Nee Jursny N.m }..k CoonantioW M1tasxuchu+aus Pennsphania 'rexns MIA..aw

F'rieniLh•C1.�.= t\��`S�-\ /' � � . .1( :.r�`` ��- 'JI`��l%\ \�' ������' -r Z.:—
/��—��v .�• ,�)l.�-_ � �y �o f�rV � �. 2il �.� iPdlk .
°IU ; � 2 : .`_ `'_./` J'-• `
I%I� o `//'_ r^L� ��}I �I� ' � e 1 41s r°i � �s.• .. ,i JJ rf � a I
�• ' c �,.�`-�i�t � i '�, ,gyp+ , � �'\c
DJ
y A fU\ \J \[ LlkAr. n rm �•'
aemgSla
4-'. �I .1� I ..�?-1\�I_ , nCl. a (�! \ ��-'°�•,.-^ _ t
;i. a J
.�. •'t C•i�1. yyt �/r2 i� i l"°`.r, em •.�P \-.I..._ \Q., ��M� 4�
nemen
YJ�r°s / 3 'rg2t 11r -0`b 6'� �. O _'� J 1 �• I' Ln .. LL oc \lil C�J
IN
• ou.• - \! '1 .1\`� - j/^. Apr P� �,/ 1) /�(/^ �l��u•
Wl
���� ,.. �� � �-�\I l\,✓�Y�./�j Imo_ � `��� �tl` � /�'� .o C.\•;\1 �1° / '�
\J WI em �/�..`r. .l`'lt ifi: ( 5� .` '�!!(• 1 n\ c�.
�r �� �e 1\�`�l , 'ram — ' .. � :�� e��.•
WILKESBORO, N.C.
N3807.5 - N`8107.5/7.5
1988
TOWN. OF WILKESBORO Dewberry & Davis
CONSULTING ENGINEERS
WASTEWATER TREATMENT 800 MaNCTON AVE ' CHARLOTTE. N.C. 28203
PLANT SITE DATE
un MAP 1

Department of Environment,
Health and Natural Resources ( �
Division of.Environmental Management
James B. Hunt, Jr., Governor
Jonathan B. Howes, Secretary
�.. . A. Preston Howard, Jr., P.E., Director H N
January 6, 1995
Mr. Norman Call, Town Manager
Town of Wilkesboro
100 West Street
Wilkesboro, North Carolina 28697
SUBJECT: Correction to June 6, 1994 speculative limits letter
Includes interaction with the Town of North Wilkesboro's WWTP
Speculative Limits for Town of Wilkesboro Wastewater Treatment Plant
NPDES Permit No. NCO021717
Wilkes County
Dear Mr. Call:
Your request for speculative effluent limits for the proposed expansion of the
Wilkesboro WWTP to 7.5 MGD and 10 MGD has been corrected by the Technical Support
Branch to include interaction with North Wilkesboro Wastewater Treatment Plant. In
order to receive final permit limits, a formal application will have to be submitted to the
Division's Permits and Engineering Unit.
Based on available information the corrected tentative limits for conventional
constituents are:
Summer Winter Summer Winter
Wasteflow (MGD) 7.5 7.5 10 10
NI-13-N (mg/1) 11 monitor 9 24
It should be noted that the tentative NI-I3N limits were evaluated including North
Wilkesboro's WWTP discharge and are based on the protection of Yadkin River against
instrcam toxicity. North Carolina is currently evaluating all NPDES dischargers for
ammonia toxicity and following EPA guidance to protect the waters for an instrearn criteria
of 1 mg/l in the summer and 1.8 mg/I in the .winter, under 7Q10 flow conditions.
FICeC
CHARLMTE, K C.
JAN 17 1995
ROUTED TO DISPOSrnON_
P.O. Box 29535, Raleigh, North Carolina 27626-0535 Telephone [phone] FAX [phone]
An Equal Opportunity Affirmative Action Employer 50% recycled/ 10%post-consumer paper

Letter to Mr. Call
page 2 P
This information should provide some.assistance in your planning endeavors.. As
previously mentioned, final NPDES effluent limitations will be determined after a formal
permit application has been submitted to the Division. If there are any additional questions
concerning this matter, please feel free to contact Ruth Swanek or Michelle Wilson of my
staff at [phone].
in rely,
Donald L. S t
Assistant Chief fo�Techn* upport
Water Quality Sectio?J
DLS/NUAW -
cc: Frank C. Cockinos &Associates, Inc.: Attn: Bo Moorefield
Winston-Salem Regional Office
Permits and Engineering Unit
Central Files
c_.

` ,DldlC; UI INUltll k�dl0lllld '
Department of Environment
Health and Natural Resources A
Division of Environmental Management
I ev
James B. Hunt, Jr., Governor
Jonathan B. Howes, Secretary [D E ^ , F1
A. Preston Howard, Jr., P.E., Director , V
June 6, 1994
Mr. Norman Call, Town Manager
Town of Wilkesboro
100 West Street
Wilkesboro, North Carolina 28697
SUBJECT: Speculative Limits for Town of Wilkesboro Wastewater Treatment Plant
NPDES Pemut No. NCO021717
Wilkes County
Dear Mr. Call:
Your request for speculative effluent limits for the proposed expansion of the
Wilkesboro WWTP to 7.5 MGD and 10 MGD has been completed by the Technical
Support Branch. In order to receive final permit limits, a formal application will have to
be submitted to the Division's Permits and Engineering Unit.
Based on available information the tentative limits for conventional constituents are:
Summer Winter Summer Winter
j. Wasteflow (MGD) 7.5 7.5 10 10
' BOD5 (mg/1) 30 30. 30 30 7" >�
NH3-N (mg/1) 14 monitor 11 monitor zI• ^ - '
TSS (mg/1) 30 30 30 30
Fecal Coliform (#/100ml) 200 200 200 200 U°
pH (SU) 6-9 6-9 6-9 6-9 6 `' 4- 1
Chlorine(ltg/l) 28 28 28 28 28 08
It should be noted that lie tentative NH3N limits were evaluated and are based on
�o` the protection of Yadkin River against instream toxicity. North Carolina is currently
evaluating all NPDES dischargers for ammonia toxicity and following EPA guidance to
protect the waters for an instream criteria of 1 mg/1 in the summer and 1.8 mg/1 in the
I o winter, under 7Q10 flow conditions.
In addition, under current Division of Environmental Management (DEM)
procedure, dechlorination and chlorine limits are now recommended for all new or
expanding dischargers proposing the use of chlorine for disinfection. An acceptable level
of chlorine in your effluent is 28 µg/l to ensure protection against acute toxicity.
The process of chlorination/dechlorination or an alternate form of disinfection, such as
ultraviolet radiation, should allow the facility to comply with the total residual chlorine
limit.
P.O. Box 29535, Raleigh, North Carolina 27626-0535 Telephone [phone] FAX [phone]
An Equal Opportunity Affirmative Action Employer 50% recycled/ 10%post-consumer paper

Letter to Mr. Call
page 2 -
The instream waste concentration at 7.5 MGD is 5.6% and at 10 MGD is17.0%. A
chronic toxicity testing requirement with quarterly monitoring will remain a condition of the
NPDES permit- A complete evaluation of limits and monitoring requirements for metals
and other toxicants will have to be addressed at the time of formal NPDES application.
Information concerning these constituents is not readily available but the Town can assume
that effluent limits and/or monitoring for cadmium, chromium, nickel, lead, cyanide,
mercury, copper, zinc, and silver should be included.
DEM has implemented a statwide basin water quality management initiative. Prior
to finalization of the Basin Plan, a flow profile of the Yadkin River will be completed by
the United States Geological Survey which may change the flow estimates at your
discharge location. Limits are subject to change based on the flow profile results. Our
schedule for implementation in the Yadkin River Basin is set for 1999. The plan will
attempt to address all sources of point and nonpoint pollutants where deemed necessary to
protect or restore water quality standards. In addressing interaction of sources, wasteload
allocations may be affected. Those facilities that already have committed to high levels of
treatment technology are least likely to be affected. The Town of Wilkesboro may want to
consider the implementation of this basinwide strategy in planning't}teir expansion, as
opposed.to limits proposed here which only address localized receiving waters of the
Yadkin River.
This information should provide some assistance in your planning endeavors. As
previously mentioned, final NPDES effluent limitations will be determined after a formal
permit application has been submitted to the Division. If there are any additional questions
concerning this matter, please feel free to contact Ruth Swanek or Michelle Wilson of my
staff at [phone].
iilcerel.y, ,
Donald L. S rit, P. .
Assistant Chie ical Support
Water Quality Section
DLS/MMW
cc: Frank C. Cockinos & Associates, Inc.
Winston-Salem Regional Office
Permits and Engineering Unit
Central Files