HomeMy WebLinkAboutNC0089290_Permit Issuance_20131101North Carolina
Pat McCrory
Governor
Ms. Christine Bralley
Town Manager
Town of Mocksville
171 Clement Street
Mocksville, NC 27028
Dear Ms. Bralley:
,�
r
NCDENR
Department of Environment and
Division of Water Resources
Water Quality Programs
Thomas A. Reeder
Director
November 1, 2013
Natural Resources
John E. Skvarla, III
Secretary
Subject: NPDES Permit Issuance.
Permit NCO089290
Mocksville - Hugh A. Lagle WTP
Davie County
The Division of Water Resources (Division) personnel have reviewed and approved your application for
issuance of the subject permit. Accordingly, we are forwarding the attached NPDES discharge permit. It
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.
There are changes to this permit from the draft permit dated August 14, 2013 :
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.
a. The requirement to begin reporting discharge monitoring data electronically using the NC
DWR's Electronic Discharge Monitoring Report (eDMR) internet application has been added
to your fmal NPDES permit. [See Special Condition A (3)] For information on eDMR,
registering for eDMR and obtaining an eDMR user account, please visit the following web
page: ba://portal.ncdenr.org/web/wg/admin/boglipu/edmr. Please note that the address to
send hard copies of DMR reports listed in the permit is slightly different from the address
shown on forms previously sent to you.
1617 Mail Service Center, Raleigh, North Carolina 27699-1617
Location: 512 N. Salisbury St Raleigh, North Carolina 27604
Phone: 919.807-63001 Fax: 919-807-6489
Internet:: www.ncwatemualh.org
An Equal Oppodunit WirrnaBveAction Employer
b. For information on EPA's proposed NPDES Electronic Reporting Rule, please visit the
following web site: http://www2 epa gov/con lip ance/roronosed-nodes-electronic-reporting_
rule.
c. A new footnote (1) has been added to Condition A.(1) regarding eDMR implementation. The
other footnotes were renumbered accordingly.
d. A new Special Condition A.(3) has been added to address the requirements of the eDMR
program.
The effective date of this permit is December 1, 2013. The limits become effective starting on December
1, 2015. The permit will expire at midnight on November 29, 2016; you must apply for renewal 6 months
in advance of this date.
If any parts, measurement frequencies, or sampling requirements contained in this permit are
unacceptable, you have the right to an adjudicatory hearing upon written request within thirty (30) days
after receiving this letter. Your request must take the form of a written petition conforming to Chapter
150B of the North Carolina General Statutes, and must be filed with the Office of Administrative
Hearings, 6714 Mail Service Center, Raleigh, North Carolina 27699-6714. Unless such demand is made,
this permit remains final and binding.
This permit is not transferable except after notifying the Division of Water Resources. The Division may
modify and re -issue, or revoke this permit. Please notice that this permit does not affect your legal
obligation to obtain other permits required by the Division of Water Resources, the Division of Land
Resources, the Coastal Area Management Act, or other federal or local governments.
If you have questions, or if we can be of further service, please contact Jim McKay at
iames.mckavCa_)ncdenr.gov or call (919) 807-6404.
Sincerely,
Thomas A. Reeder
Enclosure: NPDES Permit FINAL NCO089290: Town of Mocksville -Hugh A. Lagle WTP
cc: Winston - Salem Regional Office, Surface Water Protection with Fact Sheet - via email
NPDES Unit
Central Files
Charles A. Willis Jr., P.E. of Willis Engineers, Inc. - via email (chuck@willisengineers.com)
Permit NCO089290
STATE OF NORTH CAROLINA
DEPARTMENT OF ENVIRONMENT AND NATURAL RESOURCES
DIVISION OF WATER RESOURCES
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
Town of Mocksville
is hereby authorized to discharge wastewater from a facility located at the
Hugh A. Lagle WTP
771 Sanford Avenue
Mocksville
Davie County
to receiving waters designated as UT of Bear Creek in the Yadkin River Basin
in accordance with effluent limitations, monitoring requirements, and applicable conditions set forth in
Parts I, H, III and IV hereof.
This permit shall become effective December 1, 2013
This permit and authorization to discharge shall expire at midnight on December 31, 2016.
Signed this day November 1, 2013
fi"UL- e�- '0�-
T as A. Reed , Director
vision of Water Resources
By Authority of the Environmental Management Commission
Page 1 of 6
Permit NCO089290
SUPPLEMENT TO PERMIT COVER SHEET
The Town of Mocksville is hereby authorized to:
1. Continue to operate a conventional water treatment plant with a discharge of filter -backwash,
sediment basin flush and untreated raw water.
This conventional water treatment plant has a design potable flowrate of 2.0 MGD and a monthly
average wastewater discharge of 0.0675 MGD, up to a peak of 0.081 MGD. The facility is located
at Mocksville's Hugh A. Lagle WTP (771 Sanford Avenue, Mocksville) in Davie County.
A wastewater treatment facility will be constructed in order to treat filter backwash and other
wastewater streams. During the construction period, a 24 month compliance schedule is granted,
such that during the construction of the treatment system, certain limits and conditions will not be
enforced for a maximum of 24 months after the effective date of this permit.
Wastewater will be treated by two 250,000 gallon flow equalization tanks that equalize flows from
filter backwash and sediment basin cleaning. Solids will be allowed to settle, and the water
dechlorinated with sodium thiosulfate liquid solution before discharging to an unnamed tributary of
Bear Creek in the Yadkin River Basin. A continuous recording flowmeter will measure the
discharge of treated wastewater. Solids will be pumped out as a sludge and land applied by a
contract hauler as needed.
2. Discharge from said treatment works at the location specified on the attached map into a UT to
Bear Creek, classified WS-IV waters in the Yadkin River Basin.
Page 2 of 6
Permit NCO089290
Part I
A. (1.) EFFLUENT LIMITATIONS AND MONITORING REQUIREMENTS
a. 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 1 by the Permittee as specified below:
EFFLUENT
CHARACTERISTICS
_
LI1VtITS 2
MONITORING. REQUIREMENTS,
- -
;: Monthly`
Average.,
Daily,
Maximum..
:Measurements
.Fre uenc ... ,
.Sample Type
Sample;Locatio, ;
Flow 2
Continuous
Recording
Effluent
Total Suspended Solids
30.0 m
45.0 m
2/Month
Grab
Effluent
H 2
>_ 6.0 SU
>_ 9.0 SU
2/ Month
Grab
Effluent
Total Residual Chlorine 2,4
17
2/ Month
Grab
Effluent
Turbidity
2/ Month
Grab
Effluent
Turbidity
Monthly
Grab
Up, Down
Total Iron
Quarterly5
Grab
Effluent
Total Copper
Quarterly5
Grab
Effluent
Manganese
Quarterly5
Grab
Effluent
Fluoride
Quarterly5
Grab
Effluent
Total Zinc
uarterl 5
Grab
Effluent
Aluminum
Quarterly5
Grab
Effluent
Total Nitrogen
Quarterly
Grab
Effluent
Total Phosphorus
Quarterly
Grab
Effluent
Whole gent Toxicity
Monitoring
rin
Monitor and Report
Quarterly
Grab
Effluent
Footnotes:
1. No later than 90 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 (3).
2. Limits, including the requirement for continuous flow recording become effective December 1, 2015, or upon
completion of the wastewater treatment facilities, whichever comes first. Instantaneous flow estimates and
discharge duration shall be recorded until the flowmeter is operational. Upon completion of construction of
wastewater treatment facilities, the Town shall notify the Winston-Salem Regional Office of DENR at (336) 771-
5000, and the Central Office of the Division of Water Resources, NPDES Permitting Unit at (919) 807-6390. All
limits become effective the first of the next month. Monitoring is required beginning on the effective date of this
permit.
3. Up is Upstream in Bear Creek at least 50 feet above Discharge location, Down is Downstream in Bear Creek at
least 100 feet below Discharge location.
4. Limit and monitoring apply only if chlorine or chlorine derivatives are used for disinfection. The Division shall
consider all effluent TRC values reported below 50 µg/ L to be in compliance with the permit. However, the
Permittee shall record and submit all values reported by a North Carolina certified laboratory (including field
certified), even if these values fall below 50 µg/ L.
5. Parameter should be sampled in conjunction with Quarterly Toxicity Testing.
6. Monitoring for Zinc is only required if zinc containing additives are added to water used for filter backwash.
7. Total Nitrogen (TN) = (NO2-N + NO3-N) + TKN where NO2 N and NO3-N are Nitrite and Nitrate Nitrogen,
respectively and TKN is Total Kjeldahl Nitrogen.
8. Whole Effluent Toxicity Monitoring (Ceriodaphnia dubia) at 90%; March, June, September and December, refer
to Special Condition A. (2.).
b. All samples must be collected from a typical discharge event.
c. There shall be no discharge of floating solids or visible foam in other than trace amounts.
Page 3 of 6
Permit NCO089290
A. (2.) CHRONIC TOXICITY PASS/FAIL MONITORING (QUARTERLY)
The permittee shall conduct quarterly chronic toxicity tests using test procedures outlined in the "North
Carolina Ceriodaphnia Chronic Effluent Bioassay Procedure," Revised December 2010, or subsequent
versions.
The effluent concentration defined as treatment two in the procedure document is 90%. The testing shall be
performed as a Ceriodaphnia dubia 7-day pass/fail test. The tests will be performed during the months of
March, June, September and December. 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.
All toxicity testing results required as part of this permit condition will be entered on the Effluent Discharge
Monitoring Form (MR-1) for the month in which it was performed, using the parameter code TGP3B.
Additionally, DWR Form AT-1 (original) is to be sent to the following address:
Attention: North Carolina Division of Water Resources
Environmental Sciences Section
1621 Mail Service Center
Raleigh, N.C. 27699-1621
Completed Aquatic Toxicity Test Forms shall be filed with the Environmental 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 and accurate and include all supporting chemical/physical measurements performed
in association with the toxicity tests, as well as all dose/response data. 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, then monthly
monitoring will begin immediately. Upon submission of a valid test, this monthly test requirement will revert to
quarterly in the months specified above.
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.
If the Permittee monitors any pollutant more frequently then required by this permit, the results of such
monitoring shall be included in the calculation & reporting of the data submitted on the DMR & all AT Forms
submitted.
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 4 of 6
Permit NCO089290
A (3) 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 H 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 90 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:
hn://portal.nedenr.or web/wq/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 5 of 6
Permit NC0089290
2. Signatory Requirements [Supplements Section B. (11.) (b) and supersedes Section B. (11.) (d)l
All eDMRs submitted to the permit issuing authority shall be signed by a person described in Part H,
Section B. (11.)(a) or by a duly authorized representative of that person as described in Part I1, 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:
hM://portal.nedenr.or web/wg/admin/bodipu/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 orpersons who manage the system,
or those persons directly responsible for g6thering the information, the information submitted is, to the best
of my knowledge and belief, true, accurate, and complete. I 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 ] .
Page 6 of 6
a
Bear Creek
Outfall 001
.Ma TNM
ILL
Latitude: 35' 53' 22"
Longitude: 80' 34'43"
Facility
NCO089290
Quad# D16NE/Mocksville
Location
Stream Class: WS-IV
Subbasin: 03 07 06
Town Of 1VIOC1{SVllle
(not to scale)
HUC: 030401020603
Receiving Stream: UT to Bear Creek
Hugh A. Lagle WTP
Davie County
Yadkin River Basin
North
DENR/DWR
FACT SHEET FOR NPDES PERMIT DEVELOPMENT
NPDES No. NCO089290
Facility Information
Applicant/Facility Name:
Town of Mocksville/ Hugh A. La le Water Treatment Plant
Applicant Address:
171 Clement Street, Mocksville North Carolina 27028
Facility Address:
771 Sanford Avenue, Mocksville North Carolina 27028
Permitted Flow
Not limited. Design capacity is up to 0.081 MGD at maximum flow.
Type of Waste:
Conventional filter backwash
Facility/Permit Status:
Existing facility, new permit
Facility Classification
PC I
County:
Davie
Miscellaneous
Receiving Stream:
UT to Bear Creek
Regional Office:
Winston-Salem
Stream Classification:
WS IV
State Grid/
USGS TooQuad:
D16NE/
Mocksville
303(d) Listed?
Impaired on 2012
Final List for copper
and Ecological/
biological Integrity
Permit Writer:
Jim McKay
Subbasin:
03-07-06
Date:
I October 25, 2013
12 digit HUC:
030401020603
Facility Location
(NTS)
Drainage Area mi2):
N/A
Summer 7 10 cfs):
0
Winter 7Q10 (cfs):
0
30Q2 (cfs):
0
Average Flow (cfs):
0
IWC (%):
100 ca ed at 90%
Primary SIC Code: 1
4941
SUMMARY:
The Town of Mocksville uses a Conventional Water Treatment Plant to treat water drawn from Hunting
Creek, which is impaired for low pH on the 2012 final 303(d) list. The facility is designed to provide 2.0
Million Gallons per Day of treated potable water. The backwash wastewater is estimated to be 0.081
Million Gallons per Day at peak rates. Wastewater is comprised of filter backwash and sediment basin
cleaning flushes, and consists of finished treated water containing chlorine, fluoride and untreated source
water. It is discharged to an Unnamed Tributary of Bear Creek in the Yadkin River Basin. In current
operation, fixed speed intake pumps on Hunting Creek can cause untreated intake water to overflow the
sediment basin with raw influent water. This can lead to high turbidity in the effluent of over 500 NTU.
Bear Creek is not impaired for turbidity, so no limit is being placed in the permit, however, since the
stream is known to have a high turbidity, monitoring of the effluent along with upstream and downstream
monitoring will be required. Removal of this requirement or a reduction in turbidity sampling can be
requested at permit renewal and will be based on effluent compliance with the NC WQS of 50 NTU and/
or the consistent demonstration of naturally high levels of turbidity caused by natural background levels
and not the permittee's discharge.
The receiving stream (Bear Creek) is classified WS-IV waters in the Yadkin River Basin. This reach is
listed on the 2012 Approved 303(d) list as impaired for copper and Fair Bioclassification Ecological/
biological Integrity Fish Community.
Town of Mocksville Hugh A. Lagle WTP Fact Sheet
NPDES Permit. NCO089290
Page 1 of 3
This Conventional WTP has been operating without an NPDES discharge permit since 1946, and has
been expanded and modified during this time frame. The goal of this permit is to bring the town into the
NPDES Program, with a compliance schedule to allow the Town to construct facilities required to meet
the terms of the NPDES Permit, including TRC, Flow Monitoring, Total Suspended Solids (TSS), pH,
Turbidity and Whole Effluent Toxicity Monitoring (WET).
Permit History:
The Winston-Salem Regional Office discovered that the WTP had been operating without an NPDES
discharge permit, and began working with them to understand the requirement to have a permit for
discharge of filter backwash and other waste streams. The facility first applied for an NPDES Discharge
permit for filter backwash discharge on November 16, 2012. An Engineering Alternatives Analysis
document was attached. The EAA evaluated three options: Surface Water Discharge, Discharge to a
WWTP, and Spray Irrigation/ Non -Discharge. All three were evaluated and costed out as required. The
recommended alternate of surface discharge to Waters of the State was accepted as the lowest cost,
environmentally acceptable alternative. A Draft NPDES permit was prepared based on the application
and Engineer's report, and submitted for public notice and draft review in December of 2012. During the
review period two things happened. First, the Town decided that it could not afford to construct the
treatment facility as designed, and secondly, the Engineer retired from practice. The permit was put on
hold until the Town located another Engineer to develop a more affordable treatment system that would
meet NPDES Permit requirements. A compliance schedule of 24 months was negotiated with the Town
and the consultant in order to provide time to construct treatment facilities required to meet the permit
requirements. The earlier draft permit was modified to allow for a 2-year compliance schedule before
limits were enforced. Monitoring for all required parameters will begin on the permit effective date. The
permit expiration date per the Basin plan would be April 30, 2014, which would not be sufficient time to
complete construction and produce data for review. A permit life of three years was chosen to allow 24
months construction and 12 months of operational data for renewal. This puts the permit out of synch.
with the Basin Plan, so it is recommended that the first renewal be for the expiration to be on April 30,
2019 to be back on the Basin Schedule. This will provide a little less than two and one-half years for this
first renewal permit.
PermittingStrategy:
trate :
Permitting Strategies for Conventional Water Treatment Plants and Zero Flow streams are followed for
this facility.
Limits for TSS, pH and TRC are taken from the WTP Permitting Strategy for Conventional Water
Treatment Plants. Monitoring for Turbidity is required for the effluent and instream (Up and
Downstream of the discharge point). If data shows that the discharge has the possibility of affecting
instream turbidity, the renewal should add a Turbidity Limit in accordance with current Permitting
Strategy.
Facility Description:
The existing WTP has several fixed speed pumps of various capacities, with an intake in Hunting Creek.
Raw water is pumped to the WTP where it is flow metered and dosed with chlorine, caustic, phosphate,
fluoride and a polyaluminum chloride flocculant. There are two 45,000 gallon settling tanks with a
chemical mixer, and one 112,000 gallon settling tank with a chemical mixer. The water enters a settling
tank and solids allowed to settle out. Clear water is decanted out and filtered, then stored in a 1.0 MG
clearwell for finished water. The finished water is flow metered and pumped to the Town's Distribution
System. Filters are backwashed with finished water, and discharged to an unnamed tributary to Bear
Creek. Settling tank rinsewater and uncontrolled untreated raw water are also discharged to the UT.
The Town proposes to construct two 250,000 gallon concrete storage and settling tanks for filter
backwash and sedimentation basin flush, with floating decanting systems to drain clear water from the
solids. An 8 inch Parshall Flume will measure discharge flow rate, which will be continuously recorded
and totalized. A dechlorination system will be provided, using liquid sodium thiosulfate. The treated
wastewater will discharge to a UT to Bear Creek. Solids will be removed by a contractor for disposal
Town of Mocksville Hugh A. Lagle WTP Fact Sheet
NPDES Permit NCO089290
Page 2 of 3
offsite. Existing facilities will be repaired/ upgraded to improve flocculation and sedimentation basin
operation. The plant has various raw water pumps available with different flowrates that can be selected.
By choosing the right pump, and controlling the plant throughput to match the raw water feed rate, the
operators are able to minimize overflow and discharge of untreated water to the wastewater disposal
system.
Whole Effluent Toxicity Testing:
Chronic toxicity testing using Ceriodaphnia dubia at 90 % will be required per the permitting strategies
for Conventional WTPs and for zero flow streams.
Basis For Limits:
Limits in the permit for Total Dissolved Solids (TDS), pH and Total Residual Chlorine (TRC) are based
on North Carolina water quality standards [15A NCAC 2B .0200].
Electronic Reporting of Data:
In accordance with recent EPA requirements for Electronic Reporting of Data, a new special condition
A (3) ELECTRONIC REPORTING OF DISCHARGE MONITORING REPORTS was added to the
final permit regarding electronic submittal of data required by the permit. The permittee was advised of
this by email one week prior to issuance of the permit.
PROPOSED SCHEDULE FOR PERMIT ISSUANCE:
Draft Permit to Public Notice:
September 2013 (est.)
Permit Scheduled to Issue:
November 1, 2013 (est.)
Permit Effective Date:
December 1, 2013 (est.)
2-year Compliance Schedule ends:
December 1, 2015 (est.)
Permit Expiration Date:
November 30, 2016 (est.)
First Renewal Expiration Date:
April 30, 2019 (Basin Schedule)
STATE CONTACT:
If you have any questions on any of the above information or on the attached permit, please contact Jim
McKay at (919) 807-6404, or by email at James.McKay@ncdenr.gov.
M "1-' % DATE: t (i- 3/ 2. a13
REGIONAL OFFICE COMMENT: (USE EXTRA SHEETS IF NEEDED)
NAM
NPDES SUPERVISOR COMMENT:
Town of Mocksville Hugh A. Lagle WTP Fact Sheet
NPDES Permit NCO089290
Page 3 of 3
VCE1NRR
North Carolina Department of Environment and Natural Resources
i
Division of Water Resources
Water Quality Programs
Pat McCrory Thomas A. Reeder John E. Sltvarla, III
Governor Director Secretary j
September 11, 2013
MEMORANDUM
To: Lisa Edwards
NC DENR / DWR/ Regional Engineer
Winston-Salein Regional Office
From: Jim McKay
Com lex NPDES Permitting
8
Subject: Review of proposed NPDES Permit NCO089290
Hugh A. Lagle WTP, Davie County.
Please indicate below your agency's position or viewpoint on the draft permit and return this form by
October 18, 2013. If you have any questions on the draft permit, please contact me at telephone number
(919) 807-6404, or via e-mail at James.McKay@iicdcni-.gov.
ncdcni•.gov. !
RESPONSE: (Check one)
Concur with the issuance of this permit provided the facility is operated and maintained properly, the stated
effluent limits are rnct prior to discharge, and the discharge does not contravene the designated water quality
standards.
❑ Concurs with issuance of the above permit, provided the following conditions are niet:
i
Opposes the issuance of the above pcnnit, based on reasons stated below, or attached: '
1II
1
Signed' - Date:_
i
1617 Mail Service Center, Raleigh, North Carolina 27699-1617
Location: 512 N. Sallsbury St. Raleigh, North Carolina 27604
Phone. 94-807.63001 Fax: 91 M7.6489 i
Internet: mvw.nmateraualilxom i
An Equal OpportunitylArfirmative Won Erralever
NORTH CAROLINA
FORSYTH COUNTY
AFFIDAVIT OF PUBLICATION
Before the undersigned, a Notary Public of said County and State, duly
commissioned, qualified, and authorized by law to administer oaths, personally
appeared D.H. Stanfield, who being duly sworn, deposes and says: that he is
Controller of the Winston-Salem Journal, engaged in the publishing of a
newspaper known as the Winston-Salem Journal, published, issued and
entered as second class mail in the City of Winston-Salem, in said County and
State: that he is authorized to make this affidavit and sworn statement: that the
notice or other legal advertisement, a true copy of which is attached hereto,
was published in the Winston-Salem Journal on the following dates:
September 14, 2013
and that the said newspaper in which such notice, paper document, or legal
advertisement was published was, at the time of each and every such
publication, a newspaper meeting all the requirements and qualifications of
Section 1-597 of the General Statutes of North Carolina and was a qualified
newspaper within the meaning of Section 1-597 of the General Statutes of
North Carolina.
This 17th day of September, 2013
(signature ofper )making affidavit)
Sworn to and subscribed before me, this 17th day of Sep ber, 2013
Nota ublic
My Commission expires: September 28, 2015
EmYasKIMALEY JOHNSON
NOTARY PUBLIC
FORSYTH COUNTY p
______..
E OF NORTH AR Lill Zol
MISSION EXPIRE
PUBLIC NOTICE
North Carolina Environmental
Management Commission/NPDrS Unit
1617 Mail Service Center
Raleigh, NC 276SS-1617
Notice of Intent to Issue a
NPDES Wastewater Permit
WSJ: September 14, 2013
From:
Mckay, James
Sent:
Thursday, January 03, 2013 1:18 PM
To:
'Christine Bralley'
Cc:
Geoff Beane
Subject:
RE: Pending NPDES permit
Ms. Bralley:
A compliance schedule allows for time to modify a facility in order to comply with new permit requirements that
the existing facility cannot meet. Usually they are used when permitting requirements are changed for an
existing WWTP, but are also used in situations like yours where a new discharge permit is issued to an existing
facility that was not designed to meet the latest requirements.
Usually a compliance schedule requires the subject parameter be measured and reported, but limits are not
enforced during the compliance schedule. Once the schedule is completed, then enforcement of the limits
begins. The two items required for your permit can have combined, or separate compliance schedules,
depending on time required for each to be implemented. The compliance schedule has to be written into the
permit, using actual dates for the compliance date when limits would apply. Once the compliance schedule is
finalized, I will send a revised draft for your review.
Jim McKay, Environmental Engineer
NC DENR / Division of Water Quality / Surface Water Protection Section
Point Source Branch
1617 Mail Service Center, Raleigh, NC 27699-1617
919/807-6404 (work); 919/807-6489 (fax)
**Please note, my email address has changed to James.McKay@ncdenr.gov
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: Christine Bralley rmailto:cbrallev@mocksvillenc.govl
Sent: Thursday, January 03, 2013 12:56 PM
To: Mckay, James
Cc: Geoff Beane
Subject: FW: Pending NPDES permit
Mr. McKay,
Thank you for the information you have provided. As you are aware from the application the town would very
much like to proceed with the most cost effective means of disposal of the water plant wastewater discharge,
which would be into the receiving stream. We are very much interested in the details of a compliance schedule
and are making plans for the dechlorination and flowmeter. I will be back in contact with you within the next
few days.
Regards,
Christine W. Bralley
Town Manager
Mocksville, NC — "Time Well Spent"
file://EANC00892901RE Pending NPDES permit reply.htm
336-753-6701
From: Mckay, James [mailto:iames.mckay@ncdenr.govl
Sent: Mon 12/31/2012 11:02 AM
To: Geoff Beane
Subject: RE: Pending NPDES permit
Geoff:
I called your plant this morning and was told that you would be in at noon today. I will try to call you back this
afternoon. In the meantime:
1. The permit draft was based on the application and information supplied by your consultant. It was based
on the upgrade being completed. Since the plant modifications have not been made, I can modify the
draft permit based on your current facility.
2. Dechlorination will have to be installed, even if the modifications are not installed. I can give a
compliance schedule to allow you time to arrange funding, design/ procure/ install dechlorination
equipment before the TRC limit applies. How much time would you need? Normally we allow 6 months
for this, as it is usually a simple process.
3. A flowmeter will be required for measuring and recording the effluent from the facility. A compliance
schedule can also be granted to allow time to install a flowmeter, if needed before the requirement is in
effect. You must estimate and report effluent flowrate and duration (quantity, in units of MGD) in the
interim.
4. Do you have any data on current turbidity of the effluent from your plant? If so, please email it to me for
review. If the current plant effluent has turbidity over 50 NTU, a turbidity limit must be applied to the
permit. If not, then turbidity monitoring without a limit will remain for this permit cycle.
Jim McKay, Environmental Engineer
NC DENR / Division of Water Quality / Surface Water Protection Section
Point Source Branch
1617 Mail Service Center, Raleigh, NC 27699-1617
919/807-6404 (work); 919/807-6489 (fax)
"Please note, my email address has changed to James.McKay@ncdenr.gov
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: Geoff Beane [mailto: abeane a,mocksvillenc.govl
Sent: Friday, December 28, 2012 5:13 PM
To: Christine Bralley
Cc: Mckay, James
Subject: Pending NPDES permit
In regards to the draft NPDES permit, according to the permit the wastewater is to be treated by two 180,000 gallon
equalization tanks. We have no such structures in place. Without these tanks I believe we will not be in compliance with the
permit criteria. The plant does not have the recommended 4 hours detention time and as a result we have a good bit of carry
over floc that settles in the filter. Our filter run times are usually 22-28 hours. This unsettled floc would be discharged in the
normal wash cycle We also have to pump the water from hunting creek to the plant. We use two pumps but even at best
operation we overflow at least 50,000-100,000 gallons per day, due to filter turbidity compliance and filter washing, the basin
fills up and overflows. We currently have no way to prevent this. Hunting creek is pretty volatile with turbidity increases. this
sometimes results in the loss of treatment at the plant. The filters are placed on rewash to pull water from the basin until
treatment is restored. That wastewater too is discharged through the sample piping as the filter washwater. That can add to
file://EANC00892901RE Pending NPDES permit reply.htm
the amount of water discharged. It is an old plant it is uncertain if any leaks are adding to the current wastewater amount.
We have no flow meter in place currently to monitor this process.
As part of the upgrade package that was supposed to include the equalization tanks, there was supposed to be installed
variable speed pumps and drive units at the creek intake to better control the raw flow.
In closing I stress without the wastewater tanks or lagoons in place I fear we cannot achieve compliance with the pending
permit.
Sincerely,
Geoff Beane
Town of Mocksville WTP-ORC
W 336-751-2635
C 336-345-5636
file://E:INC00892901RE Pending NPDES permit reply.htm
Mckay, James
From:
Mckay, James
Sent:
Wednesday, January 02, 2013 8:43 AM
To:
'Geoff Beane'
Cc:
Basinger, Corey
Subject:
RE: Pending NPDES permit
Geoff:
Our office was closed shortly after 2:00 Monday and everyone was sent home, so I was not able to reply to your email.
Has the upgrade been delayed, or canceled? EPA is very sensitized to turbidity in -stream, especially when a turbidity
impaired receiving stream is impacted by turbidity coming from a discharge to it. Luckily, Bear Creek is impaired for
copper and biological integrity, but not for turbidity. We will have to require you to monitor and report turbidity in your
discharge, but no limits at this time. You should be able to continue operating as you have been, but the Regional Office
staff may be checking on turbidity more often to keep an eye on it. Hopefully you will be completing the planned
upgrades to the facility in the near future to address the turbidity issues. The dechlorination and flow meter must be
installed in a timely manner. Like I said earlier, I can give a compliance schedule to allow time to complete these two,
but the schedule will have to be met, or penalties may be issued for noncompliance.
Once we have agreed on the compliance schedule, I will make the necessary changes to the permit draft and send a
revised copy to you. Please send me all questions and comments.
Beat regards,
Jim McKay, Environmental Engineer
NC DENR / Division of Water Quality / Surface Water Protection Section
Point Source Branch
1617 Mail Service Center, Raleigh, NC 27699-1617
919/807-6404 (work); 919/807-6489 (fax)
"Please note, my email address has changed to James.McKay@ncdenr.gov
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: Geoff Beane[mailto:gbeane@mocksvillenc.gov]
Sent: Monday, December 31, 2012 2:44 PM
To: Mckay, James
Subject: RE: Pending NPDES permit
Hi, Mr. McKay:
Thanks for your quick reply. I will have to firm some things up with our town manager as to the when's regarding the
dechlor system and flow meter. Should have an answer by the end of the week. No data has ever been collected
regarding the turbidity of the waste effluent. When we wash filters, basins and have plant upsets this turbidity I would
expect to be over 50 ntu. Sometimes our raw turbidity can exceed 500 ntu after a rain event. Most the time what is
coming out of the waste line is overflowed settled water.
Also pending the permit how are basin washes to proceed?
Thanks
Geoff Beane
Town of Mocksville WTP-ORC
W 336-751-2635
C 336-345-5636
From: Mckay, James rmailto:james.mckayancdenr.go_v]
Sent: Mon 12/31/2012 11:02 AM
To: Geoff Beane
Subject: RE: Pending NPDES permit
Geoff:
I called your plant this morning and was told that you would be in at noon today. I will try to call you back this
afternoon. In the meantime:
1. The permit draft was based on the application and information supplied by your consultant. It was based on the
upgrade being completed. Since the plant modifications have not been made, I can modify the draft permit based
on your current facility.
2. Dechlorination will have to be installed, even if the modifications are not installed. I can give a compliance
schedule to allow you time to arrange funding, design/ procure/ install dechlorination equipment before the TRC
limit applies. How much time would you need? Normally we allow 6 months for this, as it is usually a simple
process.
3. A flowmeter will be required for measuring and recording the effluent from the facility. A compliance schedule
can also be granted to allow time to install a flowmeter, if needed before the requirement is in effect. You must
estimate and report effluent flowrate and duration (quantity, in units of MGD) in the interim.
4. Do you have any data on current turbidity of the effluent from your plant? If so, please email it to me for
review. If the current plant effluent has turbidity over 50 NTU, a turbidity limit must be applied to the permit. If
not, then turbidity monitoring without a limit will remain for this permit cycle.
Jim McKay, Environmental Engineer
NC DENR / Division of Water Quality / Surface Water Protection Section
Point Source Branch
1617 Mail Service Center, Raleigh, NC 27699-1617
919/807-6404 (work); 919/807-6489 (fax)
"Please note, my email address has changed to James.McKay@ncdenr.gov
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: Geoff Beane [mailto: b�Omocksvillenc.gov]
Sent: Friday, December 28, 2012 5:13 PM
To: Christine Bralley
Cc: Mckay, James
Subject: Pending NPDES permit
In regards to the draft NPDES permit, according to the permit the wastewater is to be treated by two 180,000 gallon equalization
tanks. We have no such structures in place. Without these tanks I believe we will not be in compliance with the permit criteria. The
plant does not have the recommended 4 hours detention time and as a result we have a good bit of carry over floc that settles in the
filter. Our filter run times are usually 22-28 hours. This unsettled floc would be discharged in the normal wash cycle We also have to
pump the water from hunting creek to the plant. We use two pumps but even at best operation we overflow at least 50,000-100,000
gallons per day, due to filter turbidity compliance and filter washing, the basin fills up and overflows. We currently have no way to
prevent this. Hunting creek is pretty volatile with turbidity increases. this sometimes results in the loss of treatment at the plant. The
filters are placed on rewash to pull water from the basin until treatment is restored. That wastewater too is discharged through the
sample piping as the filter washwater. That can add to the amount of water discharged. It is an old plant it is uncertain if any leaks are
adding to the current wastewater amount. We have no flow meter in place currently to monitor this process.
As part of the upgrade package that was supposed to include the equalization tanks, there was supposed to be installed variable
speed pumps and drive units at the creek intake to better control the raw flow.
In closing I stress without the wastewater tanks or lagoons in place I fear we cannot achieve compliance with the pending permit.
Sincerely,
Geoff Beane
Town of Mocksville WTP-ORC
W 336-751-2635
C 336-345-5636
AT#LAB
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
December 19, 2012
MEMORANDUM
To: Lisa Edwards
NC DENR / DWR/ Regional Engineer
Winston-Salem Regional Office
From: Jim McKay
Complex NPDES Permitting
Subject: Review of proposed NPDES Permit NCO089290
Hugh A. Lagle WTP, Davie County.
Please indicate below your agency's position or viewpoint on the draft permit and return this form by
January 19, 2013. If you have any questions on the draft permit, please contact me at telephone number
(919) 807-6404, or via e-mail at James.McKay@ncdenr.gov.
RESPONSE: (Check one)
Concur with the issuance of this permit provided the facility is operated and maintained properly, the stated
F_x] effluent limits are met prior to discharge, and the discharge does not contravene the designated water quality
standards.
F-1 Concurs with issuance of the above permit, provided the following conditions are met:
F-1 Opposes the issuance of the above permit, based on reasons stated below, or attached:
Signed `°°` P Date: 1-23-13
1617 Mail Service Center, Raleigh, North Carolina 27699-1617
Location: 512 N. Salisbury St. Raleigh. North Carolina 27604
Phone: 919-807-63001 FAX: 919-807-6489
Internet www.ncwaterauality.org
An Equal Opportunity 1 Affirmative Action Employer
Nose Carolina
�turally
NORTH CAROLINA
FORSYTH COUNTY
AFFIDAVIT OF PUBLICATION
Before the undersigned, a Notary Public of said County and State, duly
commissioned, qualified, and authorized by law to administer oaths, personally
appeared D.H. Stanfield, who being duly sworn, deposes and says: that he is
Controller of the Winston-Salem Journal, engaged in the publishing of a
newspaper known as the Winston-Salem Journal, published, issued and
entered as second class mail in the City of Winston-Salem, in said County and
State: that he is authorized to make this affidavit and sworn statement: that the
notice or other legal advertisement, a true copy of which is attached hereto,
was published in the Winston-Salem Journal on the following dates:
December 21, 2012
and that the said newspaper in which such notice, paper document, or legal
advertisement was published was, at the time of each and every such
publication, a newspaper meeting all the requirements and qualifications of
Section 1-597 of the General Statutes of North Carolina and was a qualified
newspaper within the meaning of Section 1-597 of the General Statutes of
North Carolina.
This 21st day of December, 2012tQ
(signature ofperson mapnk affidavit)
Sworn to and subscribed before me, this 21 st day of December, 2012
.Lh cr
NotaJ Public
My Commission expires: September 28, 2015
LMY
KIMALEY JOHNSON
NOTARY PUBLIC
FORSYTH COUNTY
STATE OF NORTH CAR I
OMMISSION EXPIRE
PUBLIC NOTICE
North Carolina Environmental
Management Commission/NPDES Unit
1617 Mail Service Center
Raleigh, NC 27699-1617
Notice of Intern to Issue a
NPDES Wastewater Permit
lorth Carolina Environmental Manag
Ission proposes to issue a NPDES wa
charge permit to the Persons) listed
requests to DWQ at the a
persons may visit the D
Street, Raleigh, NC to rei
Additional information on
notice may be found on of
ncdenr.org/web/wq/swp/l
by calling (919) 807-6390.
quested issuance of perm
ter Treatment Plant in Di
ted discharge is treated It
ter to a UT to Bull Creek, Ya
Par, or
ksville re -
or Its Wa-
is permit-
wastewa-
WSJ: December 21, 2012
Mckay, James
From: Basinger, Corey
Sent: Tuesday, December 11, 2012 3:06 PM
To: Mckay, James
Subject: RE: Draft NPDES Permit for Mocksville WTP
Jim,
The draft looks good. Proceed to public notice.
Many thanks.
Corey
W. Corey Basinger
Regional Supervisor
Surface Water Protection Section
Winston-Salem Regional Office
Division of Water Quality
Email: corey.basineer@ncdenr.eov
Phone: (336) 771-5000
Fax (336) 771-4630
E-mail correspondence to and from this address may be subject to the North Carolina Public Records Caw and may be disclosed to
third parties.
From: Mckay, James
Sent: Tuesday, December 11, 2012 2:58 PM
To: Basinger, Corey
Subject: Draft NPDES Permit for Mocksville WTP
Corey,
Attached is the draft for the Mocksville WTP permit. It should go out to public notice Wednesday of next week. If there
are some things that I need to change before that, please let me know. Otherwise, please send any questions or
comments to me.
Jim McKay, Environmental Engineer
NC DENR / Division of Water Quality / Surface Water Protection Section
Point Source Branch
1617 Mail Service Center, Raleigh, NC 27699-1617
919/807-6404 (work); 919/807-6489 (fax)
"Please note, my email address has changed to James.McKay@ncdenr.gov
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.
DR. F. W. SLATE
Mayor
Commissioners:
WILL MARKLIN, Mayor Pro Tem
RICHARD BROADWAY
LASH GAITHER SANFORD, JR.
ROB TAYLOR
AMY VAUGHAN-JONES
July 3, 2013
J0Wri o/
Mr. Jim McKay
NCDENR — Division of Water Quality
Surface Water Protection Section
Point Source Branch
1617 Mail Service Center
Raleigh, North Carolina 27699-1617
INCORPORATED 1839
CHRISTINE W. BRALLEY
// Town Manager
ocGZ4vi e
171 S. CLEMENT STREET
MOCKSVILLE, NC 27028
Subject: Town of Mocksville
Hugh A. Lagle Water Treatment Plant
Proposed NPDES Permit No. NC 0089290
Dear Mr. McKay:
HENRY P. VAN HOY II
Town Attorney
Thank you for your guidance in helping the Town of Mocksville secure a NPDES Permit for the
wash water discharge from our Water Treatment Plant. As you know the wash water from the
Hugh A. Lagle Plant discharges directly to an unnamed tributary of Bear Creek and does not yet
have an NPDES Permit associated with it. We have reviewed the Draft Permit provided to us in
December of 2012 and generally agree to the requirements therein; however the Draft Permit
indicates wash water is treated in two equalization basins followed by dechlorination and flow
monitoring. The Town has not yet constructed these facilities and we therefore request the
State grant additional time for us to design, permit and build these facilities prior to compliance
with the NPDES Permit. We request the State provide twenty-four months for this process to
allow us adequate time to comply with the Permit.
The facilities we proposed to build are currently being evaluated. We have engaged Willis
Engineers, Inc. of Charlotte for this evaluation. They have prepared the attached Technical
Memorandum describing several options for our consideration. The Town has elected to build
two concrete tanks and other facilities as described in the Technical Memorandum. We
therefore request the NPDES Permit reflect those facilities.
We trust this update is adequate for your needs. Should you need any additional information
please feel free to contact me or Chuck Willis at Willis Engineers (704.338.4668).
Sincerely,
Christine,W. Bralley
Town Manager
PHONE: (336) 753-6700 • FAX: (336) 751-9187
www.mocksvillene.org
Town of Mocksville, North Carolina
Hugh A. Lagle Water Treatment Plant
Wash Water Disposal
Prepared By: Charles A. Willis, Jr. P.E., BCEE
Willis Engineers (F-0114)
10700 Sikes Place, Suite 230
Charlotte, NC 28270
Date: July 1, 2013
Table of Contents
1. Overview
2. Background
3. Treatment Process Improvements
4. Storage Basin Options
5. Regulatory Requirements
6. Financial Options
7. Recommendations
Attachments
1- Overview
Technical Memorandum
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As requested, Willis Engineers has investigated options for wash water disposal at the Hugh A.
Lagle Water Treatment Plant. We understand the Plant has served the Town well for many
years, but has never been equipped with wash water disposal facilities other than a direct
discharge to a tributary of Bear Creek. Under State and Federal regulations, the Town is
required to have a National Pollutant Discharge Elimination System (NPDES) Permit for the
discharge of wash water from the Plant.
Our evaluation is intended to identify several options for wash water disposal facilities
sufficient to comply with regulatory requirements, assist the Town in negotiating an
appropriate NPDES Permit, and define the future efforts necessary to construct the wash water
facilities. The results of our evaluation and recommendations are included herein.
2 - Background
The NPDES program in North Carolina is administered by the NC Department of Environment
and Natural Resources— Division of Water Quality (DWQ). Under this program all point -source
discharges of wastewater are required to obtain an NPDES Permit, setting forth limits on the
quantity and character of wastewater to be discharged. For most water treatment plant
W�I�SENGINEERS 1
Town of Mocksville, North Carolina
Hugh A. Lagie Water Treatment Plant
Wash Water Disposal
Technical Memorandum
operations, only limited treatment is required in order to comply with normal Permit limits.
This treatment usually consists of some form of settling to remove suspended material and
dechlorination. At that point typical water treatment plant wash water has little, if any, impact
on a receiving water course.
At the Mocksville Water Treatment Plant we would expect an NPDES Permit would require daily
flow monitoring and include limits for suspended solids, total residual chlorine and regular
monitoring of several other constituents. The State has previously provided a Draft NPDES
Permit including these requirements; however, the Draft Permit assumed that adequate
treatment facilities were already in place. The Town therefore could not accept the Permit as
proposed.
The Lagle Water Treatment Plant has the capacity to produce 2.0 million gallons per day (MGD)
and currently operates between 0.8 and 1.2 MGD. Sources of wash water at the Plant include
backwash from filters, drains from sampling locations and other typical functions. In addition
to these normal daily discharges, the Plant staff will periodically drain the sedimentation basins
for cleaning resulting in a discharge of 250,000 gallons. These activities only scheduled several
times a year, nonetheless sufficient capacity should be made available for receiving this amount
of drainage.
In addition to the normal backwash functions, the Plant also has experienced some difficultly
with maintaining flow control within the treatment process. Currently the raw water pumps
located at Hunting Creek convey water to the Plant at a fixed rate. Flow through the Plant is
controlled by rate -of -flow control valves at each filter. When the raw water pumping rate
exceeds treatment rate, excess water is diverted to the overflow drains and is discharged.
All of the water draining from the Plant exits through a common drain and discharges to a ditch
in the northwest corner of the property which is tributary to Bear Creek.
3 —Treatment Process Improvements
The primary facility necessary to handle wash water from the Plant will be some form of
storage basin. This basin would allow for flow equalization, settling solids and decanting clear
water for discharge. An adequate storage basin, in combination with chemical addition for
dechlorination, should be sufficient to meet the anticipated NDPES Permit limits. Options for
the storage facilities are discussed in Section 4.
The staff has also expressed interest in reducing the total quantity of flow discharged through
the drainage system, primarily by reducing basin overflow. One option that was investigated
includes the addition of a rate -of -flow control valve on the raw water line entering the Plant.
W11181SENGINEERS
Town of Mocksville, North Carolina
Hugh A. Lagle Water Treatment Plant
Wash Water Disposal
Technical Memorandum
This valve would allow the Plant staff to control the raw water rate to match the filters, thereby
reducing overflows and the quantity of wash water produced. Although this idea has merit, we
are concerned that the addition of a raw water rate -of -flow valve will increase the operating
pressure on the raw water lines. These pipelines are made of asbestos cement and have never
been subjected to any significant pressure in the vicinity of the Water Treatment Plant. Control
of the flow in this manner may create an increased risk of a line breakage.
The Plant staff has also experimented with controlling filter flow rates to more closely match
raw water pumping rates. In recent months they been very successful in managing the flow
rate of the Plant to minimize the quantity of excess wash water produced. This management
strategy is far safer and can be accomplished without any major capital improvements. We .
would recommend replacing an existing valve on the raw water line that is difficult to operate.
This would allow for easier modulation and flow control by the operation staff.
The nature of the settled water at the Lagle Water Treatment Plant is somewhat unique. In
most treatment facilities raw water is combined with coagulant and other chemicals such that
suspended matter (turbidity) flocculates and settles to the bottom of the sedimentation basins.
At the Lagle Water Treatment Plant a substantial amount of this material tends to float to the
surface, creating a scum layer across the top of the sedimentation basins that is difficult to
remove. A portion of this floating scum is carried away when the sedimentation basins
overflow during the backwash process, but nearly half of the basin is not equipped with an
overflow drain. in the downstream sections of Sedimentation Basins 1 and 2, floating sediment
accumulates and creates a thick earth mat floating on top of the water (Photo 1). The condition
is not as bad in Sedimentation Basin 3 (Photo 2). The floating sediment may be partial
attributed to poor mixing and flocculation. The original baffle style flocculation serving basins 1
and 2 have deteriorated and should be renovated (Photo 3). Although improved mixing and
flocculation would likely help, testing tends to indicate it would not entirely eliminate floating
scum. It is therefore advisable to provide additional scum removal. Several options are
available including additional overflow pipes or a rotating weir assembly that could be utilized
during the backwash cycle to periodically remove the accumulated scum.
Prior to discharge, wash water will need to be dechlorinated. Fortunately, dechlorination can
easily be accomplished using one of several sulfur -based chemicals, either in gaseous or liquid
form. Given the size of the Plant, we recommend using liquid sodium bisulfite or sodium
thiosulfate. These chemicals can be purchased in barrels or "totes" and dispensed with a
simple chemical dosing pump.
W11I15ENGINEERS 3
Town of Mocksville, North Carolina
Hugh A. Lagle Water Treatment Plant
Wash Water Disposal
4 - Storage Basin Options
Technical Memorandum
The main component of the wash water disposal system will be the construction of storage
basins suitable for holding wash water and equalizing discharge flows. These basins should be
large enough to accommodate at least several days flow and provide for adequate storage of
sediment between cleanings. Several options for this facility have been evaluated including
construction of earthen storage basins or concrete tanks. The overall construction costs of
these facilities are similar, as demonstrated on the attached Basis of Design and Cost Estimate.
Previous proposals have included construction of several circular concrete tanks with the idea
that mechanical equipment could be provided to allow for removal of sludge, dewatering and
disposal. Unfortunately, this type of facility is fairly expensive to build and operate. If the Town
builds concrete tanks, it may wish to undertake the project in multiple phases. The first phase
would include the concrete tanks, with mechanical dewatering equipment added at a later
date.
Construction of concrete storage tanks would include two circular 250,000 gallon tanks
equipped with piping to allow water to be discharged to either basin. A floating decanter
would be provided on a flexible hose in each basin to allow staff to withdrawal clear water from
the top of the storage facility. As sludge accumulates, the basin could be drained and the
sludge removed for dewatering by a contract operator. The general arrangement of the
facilities is shown on the attached Figure 1. The estimated costs of undertaking the
improvements using concrete storage basins would be approximately $614,000.
Another option would be to construct earthen storage basins. These basins would be
somewhat larger, with each basin having a volume of approximately 400,000 gallons. The
topography of the site is difficult for the construction of earthen basins; therefore, it would be
advisable to construct these facilities closer to Sanford Avenue and utilize a pumping station.
These shallow basins will allow for increased settling time and use a similar decanter
arrangement as provided in the concrete basin. The advantage of the earthen basins is that the
sludge removal could be accomplished utilizing traditional construction equipment, possibly
undertaken by Town staff, thereby reducing the overall operating costs. The general
arrangement of these facilities is shown on the attached Figure 1.Construction costs for these
facilities would be approximately $595,000.
Another advantage to undertaking earthen basin storage is that a portion of the facilities could
be constructed by Town staff or a local grading contractor. Town staff has expressed interest in
undertaking this option and estimates that a substantial cost savings could be realized utilizing
Town forces. The disadvantage to this option is that an additional pumping station would be
1111MENGINEERS
Town of Mocksville, North Carolina
Hugh A. I.agle Water Treatment Plant
Wash Water Disposal
Technical Memorandum
required to convey drainage to the earthen storage basins. This work would likely require the
services of a specialized contractor with experience in constructing pumping stations.
5 -- Regulatory Requirements
The Town has had conversation with DWQ representatives who have indicated the willingness
to issue a NPDES Permit with substantial time available for compliance. In our conversation
with DWQ they concur that a two-year timeframe for compliance would be satisfactory which
should allow sufficient time for construction of the proposed facilities. They have also
indicated that Permit limits would likely include 30 mg/I Total Suspended Solids and 17 JLg/I
Total Residual Chlorine. Both of these limits should be achievable using either storage option
outlined above.
In addition to the NPDES Permit, the Town will need approval for construction of the new
facilities from the Division of Water Resources and Division of land Quality. These approvals
are fairly routine and could only be undertaken after issuance of the NPDES Permit and
completion of detailed construction documents.
6 - financial Options
The construction of the proposed facilities will require a significant capital investment which
may be beyond the immediate capabilities of the Town. Unfortunately, grant funds for such
work are scarce in the current economy. Several options for low or no interest financingmay
be available should the Town wish to pursue them. If the Town is to undertake a portion of the
work utilizing Town forces, it is unlikely that these loan mechanisms would be available for the
entire project. The work would likely need to be divided into multiple contracts with loan
packages arranged only for those services provided by outside contractors.
7 - Recommendations
We recommend the Town comply with NPDES requirements by entering into a Permit as issued
by DWQ. The Permit could be issued with sufficient time for construction of the facilities with
an anticipated completion date of two years. In order to undertake these improvements the
Town will first need to decide which type of facility will be constructed and undertake its
detailed design. Either concrete tanks or earthen storage basins would be acceptable and the
decision is primarily based on how much Town labor would be acceptable in the construction
and operation of these facilities.
W�IYSENGINEEAS
Town of Mocksville, North Carolina
Hugh A. Lagle Water Treatment Plant
Wash Water Disposal
Photo 1— Sedimentation Basin #2
pit ...
Photo 2—Sedimentation Basin #3
Technical Memorandum
UUIIIISENGINEERS
Town of Mocksville, North Carolina
Hugh A. Lagle Water Treatment Plant
Wash Water Disposal
Photo 3 — Baffled Flocculator
Technical Memorandum
WIIIISENGINEERS
Town of Mocksville
Wash Water Disposal
Existing Facility Improvements
Piping
Flocculation
Sedimentation Basins
Dechlorination
Chemical
Feed Method
Wash Water Storage
Type
Number and Size
Volume (each)
Piping & Valves
Inlet Piping
Outlet Piping
Flow Monitoring
Size and Type
Sampling
Controls
Preliminary Cost Estimate
Existing Facility Improvements
Dechlorination Facilities
Grading and Driveways
Back Wash Tanks
Piping and Valves
Floating Decanters and Hoses
Flow Monitoring and Sampling
Site Work and Fencing
Electrical Service
Subtotal
Construction Contingencies (10%)
Technical Services (15%)
Total Estimated Project Cost
Concrete Tank Option
Basis of Design & Cost Estimate
Raw water valve replacement
Baffle replacement
Slimmers, rotating weirs and piping
Sodium Bisulfite or Sodium Thlosulfate
Peristaltic feed pumps, manual controls
Cast -in -place concrete tanks
Two, 60-ft diameter, 12-ft SWD
250,000 gal
200 If of 12-in, isolation valves
250 If of 8-in and 12-in, floating decanters
8-in Parshall Flume
Grab sample point
Continuous flow recording, totalizer
$35,000
10,000
120,000
226,000
40,000
10,000
20,000
10,000
15,000
$485,000
$614,000
Willis Engineers
1984.001 (20)
July 2013
Town of Mocksville Earthen Basin Option
Wash Water Disposal Basis of Design & Cost Estimate
Basis of Design
Existing Facility Improvements
Piping Raw water valve replacement
Flocculation Baffle replacement
Sedimentation Basins Skimmers, rotating weirs and piping
Dechlorination
Chemical Sodium Bisulfite or Sodium Thiosulfate
Feed Method Peristaltic feed pumps, manual controls
Wash Water Pump Station
Size and Type 10-ft diameter, 20-ft deep, precast concrete
Pump Type (s) Low -head vertical turbine or submersible
Pump Capacities One @ 200 gpm, two @ 2500 gpm
Wash Water Storage
Type Earthen Basin, unlined
Number and Size Two, 140-ft by 100-ft, 5 ft deep
Volume (each) 400,000 gal
Piping & Valves
Inlet Piping 200 If of 12-1n, isolation valves
Outlet Piping 250 If of 8-in and 12-in, floating decanters
Flow Monitoring
Size and Type 8-in Parshall Flume
Sampling Grab sample point
Controls Continuous flow recording, totalizer
Preliminary Cost Estimate
Existing Facility Improvements
$35,000
Dechlorination Facilities
10,000
Back Wash Pump Station
220,000
Earthen Basin
80,000
Piping and Valves
40,000
Floating Decanters and Hoses
10,000
Flow Monitoring and Sampling
20,000
Site Work and Fencing
10,000
Temporary Dewatering Area
20,000
Electrical Service
25.000
Subtotal $470,000
Construction Contingencies (10%) 47,000
Technical Services (15%)
Total Estimated Project Cost $595,000
Willis Engineers
1984.001 (20) July 2013
/V
||PROPOSED GRAMEL
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GREY ENGINEERING, INC.
Civil Design and Surveying
P.O. Box 9 Mocksville, N.C. 27028
greyengineering.com (336)751-2110
DRAWN BY: G. BULLARD I PROJ. NO.: 102.195.13E
DESIGN BY: DATE: 11/28/12
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TOWN OF MOCKSVILLE
PROPOSED DISCHARGE LOCATION EXHIBIT 1
TO DRY DITCH ABOVE TRIBUTARY of
aceAnalyfical
wwwpacelabs.oam
July 09, 2012
Town Of Mocksville
Town Of Mocksville
771 Sanford Avenue
Mocksville, NC 27028
RE: Project: VW11'Testing 06/21/12
Pace Project No.: 92122087
Pace Analytical Services, Inc.
6701 Conference Drive
Raleigh, NC 27607
(919)834-4998
Dear Town Mocksville:
Enclosed are the analytical results for sample(s) received by the laboratory on June 21, 2012. The
results relate only to the samples included in this report.
Analyses were performed at the Pace Analytical Services location indicated on the sample analyte
page for analysis unless otherwise footnoted.
If you have any questions concerning this report, please feel free to contact me.
Sincerely,
Terri Page
terri.page@pacelabs..com
Project Manager
Enclosures
REPORT OF LABORATORY ANALYSIS Page 1 of 5
This report shall not be reproduced, except in full,
without the written consent of Pace Analytical Services, Inc..
"
Pace Analytical Services, Inc.
/� / 1 Jr
ac, laf �/f r 't l
6701 Conference Drive
wwwpBCeJa`�
Raleigh, NC 27607
(919)834-4998
CERTIFICATIONS
Project: VWV Testing 06/21/12
Pace Project No.: 92122087
Asheville Certification IDs
2225 Riverside Dr., Asheville, NC 28804
South Carolina Certification #: 99030001
Florida/NELAP Certification #: E87648
Virginia Certification #: 00072
Massachusetts Certification #: M-NC030
West Virginia Certification #: 356
North Carolina Drinking Water Certification #: 37712
VirginaNELAP Certification * 460147
North Carolina Wastewater Certification #: 40
Eden Certification IDs
205 East Meadow Road Suite A, Eden, NC 27288
Virginia Drinking Water Certification #: 00424
North Carolina Drinking Water Certification #: 37738
VirginiaAfELAP Certification #: 460025
North Carolina Wastewater Certification #: 633
REPORT OF LABORATORY ANALYSIS
This report shall not be reproduced, except in full,
without the written consent of Pace Analytical Services, Inc..
Page 2of5
aceAnalytical
www.pacelabs.com
SAMPLE ANALYTE COUNT
Project: WW Testing 06/21/12
Pace Project No.: 92122087
Pace Analytical Services, Inc.
6701 Conference Drive
Raleigh, NC 27607
(919)834-4998
Analytes
Lab ID Sample ID Method
Analysts
Reported
Laboratory
92122087001 Source EPA 9040
KPP
I
PASI-E
EPA 200.7
JMW
12
PASI-A
EPA 7470
SHI3
1
PASI-A
40CFR PART 432.2
EWS
1
PASI-A
EPA 351.2
JDA
1
PASI-A
EPA 353.2
DMN
1
PASI-A
EPA 365.1
JDA
1
PASI-A
REPORT OF LABORATORY ANALYSIS
This report shall not be reproduced, except in full,
without the written consent of Pace Analytical Services, Inc..
Page 3 of 5
aCieAnalyiical
wwwpacelab&corn
ANALYTICAL RESULTS
Project: VWV Testing 06/21/12
Pace Project No.: 92122087
Sample: Source Lab ID: 92122087001 Collected: 06/21/12 06:00
Parameters Results Units Report Limit DF Qualifiers
pH
7.4 Std. Units
0.10
1 H6
Antimony
ND mg/L
0.0050
1
Arsenic
ND mg/L
0.0050
1
Barium
0.028 mg/L
0.0050
1
Beryllium
ND mg/L
0.0010
1
Cadmium
ND mg/L
0.0010
1
Chromium
ND mg/L
0.0050
1
Iron
0.79 mg/L
0.050
1
Manganese
0.074 mg/L
0.0050
1
Nickel
ND mg/L
0.0050
1
Sodium
ND mg/L
5.0
1
Thallium
ND mg/L
0.010
1
Selenium
ND mg/L
0.010
1
Mercury
ND mg/L
0.00020
1
Nitrogen
1.8 mg/L
0.70
1
Nitrogen, Kjeldahl, Total
0.61 mg/L
0.50
1
Nitrogen, NO2 plus NO3
1.2 mg/L
0.020
1
Phosphorus
0.10 mg/L
0.050
1
Date: 07/091201210:44 AM REPORT OF LABORATORY ANALYSIS
This report shall not be reproduced, except in full,
without the written consent of Pace Analytical Services, Inc..
Pace Analytical Services, Inc.
6701 Conference Drive
Raleigh, NC 27607
(919)834-4998
Page 4 of 5
ace"Iyflcal
www. fraoeta,Ds.00m
QUALIFIERS
Project: VWV Testing 06/21/12
Pace Project No.: 92122087
DEFINITIONS
Pace Analytical Services, Inc.
6701 Conference Drive
Raleigh, NC 27607
(919)834-4998
DF - Dilution Factor, if reported, represents the factor applied to the reported data due to changes in sample preparation, dilution of
the sample aliquot, or moisture content.
ND - Not Detected at or above adjusted reporting limit.
J - Estimated concentration above the adjusted method detection limit and below the adjusted reporting limit.
MDL -Adjusted Method Detection Limit.
PRL - Pace Reporting Limit.
RL - Reporting Limit.
S - Surrogate
1,2-Diphenylhydrazine (8270 listed analyte) decomposes toAzobenzene.
Consistent with EPA guidelines, unrounded data are displayed and have been used to calculate % recovery and RPD values.
LCS(D) - Laboratory Control Sample (Duplicate)
MS(D) - Matrix Spike (Duplicate)
DUP - Sample Duplicate
RPD - Relative Percent Difference
NC - Not Calculable.
SG - Silica Gel - Clean -Up
U - Indicates the compound was analyzed for, but not detected.
N-Nitrosodiphenylamine decomposes and cannot be separated from Diphenylamine using Method 8270. The result reported for
each analyte is a combined concentration.
Acid preservation may not be appropriate for 2-Chloroethylvinyl ether, Styrene, and Vinyl chloride.
LABORATORIES
PASI-A Pace Analytical Services - Asheville
PASI-E Pace Analytical Services - Eden
ANALYTE QUALIFIERS
H6 Analysis initiated outside of the 15 minute EPA recommended holding time.
M1 Matrix spike recovery exceeded OC limits. Batch accepted based on laboratory control sample (LCS) recovery.
M6 Matrix spike and Matrix spike duplicate recovery not evaluated against control limits due to sample dilution.
Date: 07/09/201210:44 AM REPORT OF LABORATORY ANALYSIS Page 5 of 5
This report shall not be reproduced, except in full,
without the written consent of Pace Analytical Services, Inc..