NC0082949_Compliance_20120404

NPDES DOCUMENT SCANNING COVER SHEET
NC0082949
Denton WTP
NPDES Permit:
Document Type:
Permit Issuance
Wasteload Allocation
Authorization to Construct (AtC)
Permit Modification
Complete File - Historical
Engineering Alternatives (EAA)
•
..Compliance
Instream Assessment (67b)
Speculative Limits
Environmental Assessment (EA)
Document Date:
April 4, 2012
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AVA
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
April 4, 2012
Ms. Tammie Melton, Water Treatment Plant Superintendent
Town of Denton
P. O. Box 306
Denton, NC 27239
Subject: NPDES Permit Compliance Evaluation
Town of Denton WTP
NPDES Permit NC0082949
Davidson County
Dear Ms. Melton:
The Division of Water Quality (DWQ) has received your e-mail correspondence of March 8, 2012,
requesting clarification regarding DWQ's expectations with regard to operations at the Town's water
treatment plant (WTP). The primary concern expressed by the Town was DWQ's determination of
compliance with NPDES permit conditions, specifically how potential delays in completion of the WTP
upgrade project (which includes improvements to wastewater treatment infrastructure) may affect the
WTP's compliance status.
As you know, the State implemented a new strategy in 2007 for the regulation of wastewater discharges
from WTPs. The strategy's goal is to better protect surface waters through the identification of
pollutants characteristic of WTP wastewater discharges. The strategy was implemented for the Town of
Denton WTP during its 2009 permit renewal. The renewed permit required new or modified monitoring
for a number of parameters, most notably flow and whole effluent toxicity. The permit called for flow
to be monitored continuously, but provided an eighteen month compliance schedule for the installation
of an adequate flow measurement device. The compliance schedule was modified in 2011 to extend the
deadline for installation of the flow meter until January 1, 2013, in accommodation to the schedule of
the overall WTP construction project. The whole effluent toxicity requirement within the permit called
for monitoring only, but was to be reported as "pass" or "fail" with regard to the toxic effects of the
discharge on aquatic life. Since the monitoring requirement was instituted the WTP has reported
failures on seven of eight whole effluent toxicity tests.
Inherent in the issuance of NPDES permits is DWQ's firm expectation that permittees can and will
comply with the conditions contained therein. DWQ is required to enforce compliance of the permits it
issues. In the case of the Town of Denton WTP, DWQ feels that the extension of the compliance
schedule granted in the 2011 permit modification has provided the Town adequate time to install a
suitable flow measurement device. Documentation of all volumes of flow discharged by the facility is a
very important issue in determining its potential impact on water quality. As such, we will not grant any
additional extension of time in this matter. Therefore, if the flow meter is not installed and continuous
1617 Mail Service Center, Raleigh, North Carolina 27699-1617
Location: 512 N. Salisbury St Raleigh, North Carolina 27604
Phone: [phone] \ FAX: [phone]
Internet www.ncwaterquality.org
An Equal Opportunity \ Affirmative Action Employer
North Carolina
Naturally

Ms. Tammie Melton
NC0082949 - Town of Denton WTP
p. 2
flow measurements are not being reported by the January 1, 2013 deadline, the facility will be
noncompliant with the terms of the NPDES permit and may be subject to appropriate enforcement
action.
While there is currently no compliance evaluation in the matter of whole effluent toxicity testing, the
facility's reported failures of toxicity tests are of concern to DWQ. It is possible that future permits will
have requirements to identify and eliminate the causes of the toxicity failures. Therefore, the Town is
encouraged to complete its wastewater treatment upgrades at the WTP as soon as possible.
A final matter of concern to DWQ involves the facility's long term strategy for management of waste
solids generated by the facility. Too high accumulations of solids in the lagoons at the site have been
cited in past inspections as the cause of solids escaping the treatment works and entering the receiving
stream. This matter was initially resolved by the facility depositing excess solids within a bermed area
adjacent to the lagoons. However, this arrangement was approved only as a temporary means for the
storage of solids. The facility upgrade calls for improvements in the facility's ability to manage its
solids inventory. These improvements have the potential to resolve a long standing problem at the
facility, and to enhance the quality of the wastewater it discharges. DWQ fmds these to be compelling
reasons for the Town to complete the project as soon as possible.
DWQ appreciates the Town's commitment to protection of the state's water resources. Please contact
the staff of the Surface Water Protection Section within the Winston-Salem Regional Office at (336)
771-5000 should you require any assistance with onsite matters. If you have any questions about this
letter, please contact Bob Sledge at [phone], or via e-mail at [e-mail].
John E. Hennessy
Supervisor
Compliance & Expedited Permits Unit
cc: WSRO — SWP Section
NPDES File
Central Files

Sledge, Bob
• From: [e-mail]
Sent: Thursday, March 08, 2012 11:13 AM
To: Sledge, Bob
Cc: Boyd, Tom
Subject: upcoming upgrade to water treatment plant
Hello Bob and Tom,
Hope this e-mail finds you well.
While we are in the process of reviewing and completing the final plans on the upgrade at the
water treatment plant; we are asking for any thoughts, input, and REQUIREMENTS that the State
has in regards to the project at the Denton Water plant. If you could. take a few minutes and
review the submitted plans and let us know. It would be greatly appreciated. Thank you for
your time and assistance in this matter.
Thank you,
Tammie Melton
1

03/.14/2012 14:08
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TOWN OF DENTON WTP PAGE 01/06

. 03/14/2012 14:08 3368593139
TOWN OF DENTON WTP
PAGE 02/06
Michael P. Easley, Governor
• William G. Ron Jr , Secretary
Noah Carolina Department of Environment and Natural Resources
Also w. Klimek, P.E. Director
Division of Water Quality
August 28, 2006
CEUIRIED MAIL 7003 SAU 624
RETURN RCL -RQ ST
Mr. F. E. Isenhour, Town Manager
Town of Denton
P,O. Box 306
Denton, NC .28630
SUBJECT: Fermisalon for Temporary Storage of Alum Residuals
Town of Denton
Towa'Iof Denton Residuals Land Application Program
Permit No: WQ0016966
Davidson County
Dear Mr. Isenhour:
On June 22, 2005 Shannon Thornburg with the Central Office gave a verbal agreement to Chris Alexander with Precision
e c�P
Land Application, Inc. for the Town of Denton WTP granting approval for a temporary one-time stockpilingb a
residuals within the benncd area. This agreement required that the material had to be solidndCthere that t a writtenbetimeeroval
limit on the stockpiling and that a formal request letter should be submitted to the Central
could be issued. Chris Alexander submitted a formal letter to the Central Office on July 27, 2005 TSpecifically,
is letter
� al�gtht
permission "to store, on a temporary basis, dried alum sludge from their Water Treatment Facility pe
e
sought permission "to store dried alum sludge adjacent to the two alum sludge lagoons on the TP's property".
sto "get
letter g
was indicated in the letter that "the two alum lagoons are surrounded by an earthen
arbermt hat r pwould providesbcontaineddgwith the
area within the berm for the dried alum sludge and that "all surface runoff from r
berm and drained into the two abnn lagoons".
4 2005 bySteve Mammy with the Winston-Salem Regional Office Division of Water Quality
An inspection on August �
for NPDES Permit No. NC0082949 found the Town of Denton WTP to be in violation for the following:
That the treatment basins at the Denton Water Treatment Plant need to be cleaned out so that they can properly
settle the solids generated in the water purification process, Solids have escaped the treatment
facility and
arthe diked
reached the receiving stream. (There appears to be adequate room to store the solids within
area at the facility.)
'cation was received on October l0, 2005 for the Town of Denton's Land Application of
A permit renewal and; modification
Residual Solids Permit No. WQ0016966, which included the addition of the Town2of Denton
t nWTPsro approvedrenewal and
residual source -generating facility for 160 maximum dry tons per year. On May , 2006, permit
modification was issued with. the Town of Denton WTP listed in Attachment A.
Division of Water Qutilry / Aquilbr Protection Section
585 waughtown Street, Winston-Salem NC 27107
Ptcnno: [phone] Fox: (336) 7714631 Intermit: http:l/ low,o n croualirrAlg
An Equal Oppothm /A0lrmanue Action Employer— 50% Recycledlm0% Post Consumer Paper
Coco n
aturzI�y
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03i14/2012 14:08 3368593139
TOWN OF DENTON WTP PAGE 03/06
Mr. Isenhour
August 24, 2006
Page 2 of 2
From a phone conversation with Tammy Melton, ORC, with the Town of Denton WTP, it is our understanding .that the
Town of Denton seeks permission to continue to store alum sludge in a trenched area adjacent to the lagoon where any
runoff would flow into the lagoons under Non -discharge Permit No. WQ0016966. It was also understood that there were
concerns about the liming of the present lagoons in reference to any requirements needed to be met to be in compliance
with groundwater standards.
Winston-Salem Regional Office of the Division of Water Quality Aquifer Protection
the m n
Upon review of this information sto ga
Section grants permission for the temporary storage of alum sludge in the trenched area adjacent to the lagoon provided
that any runoff would flow into the lagoons and that a permanent storage method would be constructed such as additional
lagoons and/or drying bed. Operation of this method of storage should be in compliance with performance standards in
Condition 1. i.and 3.;,lof Non -discharge Permit WQ0016966 and in compliance with NPDES Permit No. NC0082949.
Previous inspections indicated that saprolitic material or weather bedrock has been exposed in the lagoons. .Maintenance
of the lagoons shoul4 be implemented to prevent further erosion and rock exposure. Minimum design requirements that
apply to the present lagoons, any proposed lagoon, and trenohes such as the ones that are being used temporary to store
eaum-sludge.ar+e found•in•North-Carolina Administrative Code 1,5/t NCAC 02H:
Carefully review all permit conditions and design requirements addressed in this letter and respond in writing to this
office within thirty (30) working days of receipt of this letter. If you should have any questions, please do not hesitate to
contact Derek Denard or me at 336-771-5000.
Sincerely.
)44"-"7"-
Sherri V. Knight, P.E.
Regional Aquifer Protection Supervisor
cc: Tammy Melton; ORC Town ofDentxm WTP (PO BOX 306, Denton, NC 27239)
Kim Colson, DWQ-APS-Land Application Unit
Steve Mauncy, DWQ-SWP-WSRO
Troy B Branch, ORC WWTP
DWQ-APS-Central Files
WSRO Files

03414/2012 14:08
3368593139
TOWN OF DENTON WTP
PAGE 04/06
Beverly Eaves Perdue
Governor
AT:4,
NCDENR COPY
North Carolina Department of Environrnenl :::ir:rf Nlatl..ir:•:+1 Re3oirueo
Divisioli of Water Qi.; Iity
Chai-ios �rvsltlld, F'.1=
Director
January 11, 2010
Honorable Scott Morris, Mayor
Town of Denton
P.O. Box 306
Denton, NC 27239-0306
SUBJECT: Compliance Evaluation Inspection
Town of Denton WTP
NPDES Permit #NC0082949
Davidson County
Dear Mr. Morris:
Coe
0-P)'pr'
IJF:o I rt!;errlal'i
S :retary
compliance
Evaluation Inspection was performed at thc Town of Denton's4WTP on December 7,
A pperator. in
2011 by lender Career of the Winston-Salem Regional Office. Ms. 'Fannie B. Melton,
Responsible Charge (ORC), was present for the inspection. This inspection consisted of a review of self -
monitoring data, an on -site inspection of, the facility, and a review of Feld parameter monitoring
equipment and records.
A review of self monitoring data for the last two years revealed only one minor limit violation that has
been previously addressed...All monitoring was performed and recorded per the frequencies specified in
the permit.
Upgrades to the plant are ongoing, and will include two new lined lagoons, back flow prevention,
continuous flow monitoring equipment and a new drying bed. In thc meantime, the Aquifer Protection
(AP) Section of the Division of Water Quality grantedtemporary permission to store alum sludge
in
drying beds next to the lagoons in a letter dated August 24,modified2006. The permit wasmodifieded to extend the
deadline for implementing continuous flow monitoring to January 1,, 2013.
The plant was p �ng properly eratiat the time of the inspection. Ms. Melton continues to do a good. job
o
maintaining optimal treatment conditions given the limited sludge storage available.
Shouldyou
ou have any questions please contact Ms. Jcnifer. Carter in our Winston-Salem Regional Office at
[phone].
cc:
SWP-Central Filcs
WSRO Files
North Carolina Division of Watcr 0twollty, Winston-Salem Regional Office
Location: 585 Waughtown St. Winston-Salem. North Carolina 27107
Phone: [phone] FAX: 336.7? 1.4630 l Covomer Service 1-971.623-6748
Internet: wwa►.nra►Atertitlal ly.org
An Enual Oovortunity t AllifMAtIVA AChon Fmp►oyN
Sincerely,
W. Corey Basinger
Surface Water Regional Supervisor
One. C3Y011[13
aiura!!y

03414/2012 14:08 3368593139
TOWN OF DENTON WTP PAGE 05/06''
IfJO^J, L ttr'J .1•`i . lv rfU1) 1Jiv Ut 41QLCl IJuaa...11.y u r r aluu0 1 r l r r WVG/ teals r- rstma
Wrfiain (i. R.(t Jr., Scuititary
Nnrth C u'oIkw nopartrnonl ne' novrmnrttcn i and Natural I(or<ourccs
Alga W ))4recear
1)ivisiurr ur Ward ()utility
August 11, 2005
Mr. 13i11,Pless, Town Manager
Town of Denton
PC) Box 306
Denton, jNC 27239
Subject
NOTICE OF VIOLATION
flatten Water Treatment Plant
NPDES 'Permit No. NC0082949
Onvidsou County
Dear M. Ness:
An inspection on August 41, 2005 revealed the following:
1. chat the treatment e t basins at the Denton Water Trciltmcnt Plant need to be cleaned
out so that they can properly settle the solids generated in the water purification
process. Solids have escaped the treatment Facility and reached the receiving
Stream. ('There appeal' to be adequate room to store the solids within the earthen -
diked area at the facility.)
2. The treatment basins do not appear to have been constn3cted According to the
plans and ;specifications. Portions of both basins are lacking a liner and the basins
do not have an operable under drain system. It is recommended that when the
basins are drained that a proper liner be installed to bring these units in
t owpbancc with the issued Authorization to Construct.
1'heldischarge of solids to the stream is in violation of North Carolirtli Cicrteral Statute
143-215.1(a) (9) and Pori Cl, Section C, 6 of your NPDES permit which states, " Solids,
sludges, filter backwash, or other pollutants removed in the coarse of treatment or control
of west6watcrs shall be utilized/d1Spuaed of in accordance with NCGS 143.215.1 and in a
lnatutcrsuch as to prevent any pollutant from entering waters of the State or navigable
water: Or the United States''. Tb` sludge must be removed immediately from the strcatn.
Failure to construct the proper wastewater treatment facility is,iusiti(ication for the
Division to revoke the Authorization to Construct that was formerly issued for this
facility,'' Acceptable plans and specifications should be subtnitted as soon as possible and
upon approval the proper treatment system must be installed. Construction its 1997 of the
treatment basins at the Denton Water *Treatment Plant without reoeipt of approval for the
N titC'aro i'
North t:arottna Division or Water straitly 395 Woutthwwn xtnxl Wirtstuu-SSIICro, NC: I1107 r'h„nc (.136) 711.4(6M Fax (.116) 771.4(131
Internet: n?o.enr.s(at(.ncdn
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03/14/2012 14:08 3368593139
TOWN OF DENTON WTP
PAGE 06/06
1- .00.3i tics.. r —oe,3
I
► • t 1vs'agually Ind was a violation of North Carolina General s10 ut.c l43-
215.1. (u) (2)•
These violations may result in the request by this office that or 1)urecr rinitiate
violation.
enforcement action. The civil penalties may be us high as $25,000 p day, P
at this site have filled with solids and as immediate action is
.� cuss .request
Roth 1 b
necessary] to prevent the further release of solids to the creek, we agree tw with
the
to
store solids from basin 02 inside the; dyke until they can be removedproper
The storage period shall not exceed 8 months. Upon cleaning bnsin112, it willl bc a unlaced
back in service and basin # 1 will be allowed to dry before solids removal. The
er
should he placed in the empty basins as soon as possible.
Shuuld you have an uestion:4 on this letter, plcase contact Steve Worley at 336-
�y y
771-4608, extension 282. Sincerely,
%K. Steve W. Tedder
Water Quality Supervisor
Cc; Tammy Melton, Town of Denton
Sherri Knight., Aquifer Protection
SWP-Central Files
WS1RU