NC0020443_Permit (Modification)_20150303

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NPDES DOCUWEHT SCAMMINC COVER SHEET
NPDES Permit: NCO020443
Columbia WWTP
Document Type: Permit Issuance
Wasteload Allocation
Authorization to Construct (AtC)
Permit Modification`
Speculative Limits
201 Facilities Plan
Instream Assessment (67B)
Environmental Assessment (EA)
Permit
History
Document Date: March 3, 2015
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NCDENR -
North Carolina Department of Environment and Natural Resources
Pat McCrory Donald R. van der Vaart
Governor Secretary
March 3, 2015
Rhett B. White, Town Manager
Town of Columbia
P.O. Box 361
Columbia, North Carolina 27925
Subject: Change-Page
NPDES Permit NCO020443
Columbia WV17P
Tyrrell County
Dear Mr. White:
The Division of Water Resources(the Division)received a request to remove quarterly Mercury monitoring
on Jan 20, 2015. After further review, it was detennined that modification of quarterly Mercury monitoring
to once per permit cycle would be consistent with our permitting strategy.
Accordingly,we hereby forward the modified pen-nit pages to amend your permit changing Mercury
monitoring to once per permit cycle. Please insert these change pages into your existing permit and discard
the old pages.
Please note that this permit is not transferable except after notice to the Division. The Division may require
modification or revocation and reissuance of the permit. This permit does not affect the legal requirements
to obtain other permits which may be required by the Division of Water Resources or any other Federal,
State, or Local governmental permits that may be required.
If you have questions, or if we can be of further service, please contact Derek Deward at
[e-mail] or call [phone],
espec ully,
ay Zimmerman, Direc
Division of Water Resources,NCDENR
Enclosure: NPDES Permit NCO020443 (Corrected Pages)
hc: Central Files
NPDES Program Files
WaRO Files/Attn:David May
1617 Mai)Service Center,Raleigh,North Carolina 27699-1617
Phone:[phone] Internet:w"w wwaterquality.org
An Equal Opportunity 4 Affirmative Acfien Employer—Made in part by recycled paper

Permit NCO020443
PART I
A. (L) EFFLUENT LIMITATIONS AND MONITORING REQUIREMENTS
During the period beginning on the effective date of the permit and lasting until expiration, the Permittee
is authorized to discharge from Outfall 001. Such discharges shall be limited and monitored' by the
Permittee as specified below:
LIMITS
EI+PIlUCNT CiI Rr1CTF.I ISTIG MONITORING.REQU,IREMENTS I
[Paraiheler-Codes]' orithly Weekly i Daily Mcasurernent r Sample Sariiple
Average Average �,Maximuin,,; FregrJency T;ype Location z
Plow(MGD) 50050 0.6 MGD Continuous Recording 1 or E
Temperature(°C) 00010 Monitor&Repo Daily Grab E
Total Residual Chlorine(lk L)3 50060 13 µg/L 3/Week Grab E
130D 5-day,20°C m 4 00310 7.0 10.5 3/Week Composite I,E
Total Suspended Solids(m )4 00530 30.0 45.0 3/Week Composite 1, B
NH3 as N(mgfL) C0610 2,0 6.0 3/Week Composite 1
Dissolved Oxygen(DO)(m ) 00300 Daily average>6.0 m L 3/Week Grab E
Enterococci(#/100mI) 5 61211 35 1100 mL 1 276/ 100 mL I 3/Week Grab E
PH(su), 00400 >6.8 and<8.5 standard units 3/Week Grab E
Total Phosphorus(m ) C0665 Monitor&Report Quarterly Composite E
TKN (mglL)6 00625 Monitor&.Report Quarterly Composite E
NO3-N-+_NO2-N (mglL)6 00630 Monitor&Report Quarterly Composite E
TN (m )6 C0600 Monitor&Report Quarterly Calculated 1:
Mercury7 COMER Monitor&Report Once per Grab E
permit cycle
Notes:
1. No later than 270 days from the effective date of this permit, the permittee shall begin submitting discharge
monitoring reports electronically using the Division's eDMR application system
[see A. (4)].
2. Sample Location: E—Effluent, I— Influent
3. The Division shall consider all effluent TRC values reported below 50 ltg/l to be in compliance with the
permit. However, the Permittee shall continue to record and submit all values reported by a North Carolina
certified laboratory(including field certified), even if these values fall below 50 µg/l.
4. The monthly average effluent BOD5 and Total Suspended Solids concentrations shall not exceed 15 percent
of the respective influent value(85%removal).
5. Enterococci shall be calculated using the geornetric rnean, according to the procedure detailed in Part D.
Section A.
6. For a given wastewater sample, TN=TKN 4-NO3-N+NOZ-N, where TN is Total Nitrogen, TKN is Total
Kjeldahl Nitrogen, and NO3-N and NO2-N are Nitrate and Nitrite Nitrogen, respectively.
7. Low level mercury analysis using EPA Method 1631E for all effluent mercury sampling is required.
Samples shall be taken at the outfall but prior to mixing with the receiving waters.
There shall be no discharge of floating solids or foam in other than trace amounts.
Page 3 of 6

Permit NCO020443
A. (2.) Nutrient Reopener
This permit may be modified, or revoked and reissued to include an effluent limitation for nutrients depending
upon the following:
➢ The findings of a study by the Division determine nutrient control is necessary.
➢ Local actions do not successfully reduce the nutrient loading on the receiving waters.
➢ The onset of problem conditions in the receiving waters.
Page 4 of 6

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Town of Columbi
'A Heart's Delight" founded in 17 2�15
103 Main Street • P.O. Box 361
Columbia, NC 27925 �p aESo�
252.796.2781 (P) • 252.796.0082(F) ONo�SOFF�oE
D��51 p�RE
January 14, 2015
Mr. Thomas A. Reeder, Director
Division of Water Resources
1617 Mail Service Center
Raleigh,NC 27699 RECEIVEDIDENRIDWR
Re: NPDES Permit NCO020443 JAN ) } 2015
Dear Mr. Reeder: Water Quality Regional
Operations Section
With this letter the Town of Columbia,NC is requesting that the North Carolina Division
of Water Resources eliminate the requirement for quarterly Mercury monitoring as a
WWTP permit requirement.
Our request is based upon the following:
1. Our investigation of the protocols necessary to collect for Mercury sampling
indicates that there are significant health hazards to the employees collecting the
samples, even with the disposable uniforms, gloves and masks. For example,
employees with fillings may be at unusual risk.
2. Two employees will be required to collect the samples, an unusual burden for a
small wastewater treatment plant with a.staffof only three employees who operate
both a drinking water and wastewater treatment plant while also maintaining a
system of storm water pumps.
3. We understand that Mercury sampling may be influenced by wind and rain. Both
are frequent conditions that we deal with.
4. There are no known Mercury contributors to the Columbia wastewater treatment
system. Our town has only two small commercial users in addition to the normal
number of small independent businesses. We are not an industrial town.
5. If Mercury monitoring is required to obtain base-line data for the State, the State
should shoulder the cost of collecting and testing, rather than passing this cost on
to the local governments or system operators.

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We respectfully request that Mercury monitoring be eliminated as a condition of
NPDES Permit NC0020443.
Thank you for your consideration.
Yours sincerely,
6��6�
Rhett B. White, Town Manager