WQ0002708_Attachments A and C Certification_20230823

ROY COOPER
Governor
ELIZABETH S. BISER
Secretary
RICHARD E. ROGERS, JR.
Director
NORTH CAROLINA
Environmental Quality
August 23, 2023
LISA JOSEPH — RESOURCE RECOVERY MANAGER
CITY OF RALEIGH
POST OFFICE BOX 590
RALEIGH, NORTH CAROLINA 27602
Subject: Permit No. WQ0002708
Wrenn Road WWTF
Attachments A and C
Certification
Wake County
Dear Ms. Joseph:
In response to your permit minor modification request received on November 21, 2022, and
subsequent additional information received on February 6, 2023, May 2, 2023, and August 16, 2023, we
are forwarding herewith modified Attachments A and C certified August 23, 2023, to the City of Raleigh
for the subject facility.
Modifications to the subject Attachments are as follows:
➢ The Division has added Footnote 3 to Attachment A. This footnote states that the Division has
approved the use of the IDEXX Colilert 18 Method for detection of Fecal Coliform when there
is no limit for Fecal Coliform.
➢ The Division has added Footnote 8 to Attachment C. This footnote states that the Division has
approved the use of the IDEXX Colilert 18 Method for detection of Fecal Coliform when there
is no limit for Fecal Coliform.
➢ The Division has revised the groundwater standard for Manganese in Attachment C to 0.057
mg/L.
➢ The Division has removed old Footnote 8 from Attachment C because the Permittee has
completed the groundwater monitoring plan and has established site -specific background
concentrations.
The modified Attachments A and C are effective from the date of certification until September 30,
2026, shall replace Attachments A and C of Permit No. WQ0002708 issued on June 16, 2021, and shall be
subject to the conditions and limitations therein, as well as those specified in the above -referenced permit.
Please replace Attachments A and C of Permit No. WQ0002708 that was issued on June 16, 2021, with the
modified Attachments A and C. The Permittee shall submit a renewal application no later than April
3, 2026.
D ��� North Carolina Department of Environmental Quality I Division of Water Resources
512 North Salisbury Street 11617 Mail Service Center I Raleigh, North Carolina 27699-1617
NORTH CAROLINI�
oew eMor imme�ia�ainv 919,707,9000

Ms. Lisa Joseph
August 23, 2023
Page 2 of 2
This certification can be contested as provided in Chapter 150B of the North Carolina General
Statutes by filing a Petition for a Contested Case Hearing (Petition) with the North Carolina Office of
Administrative Hearings (OAH) within 30 calendar days. Requirements for filing a Petition are set forth
in Chapter 150B of the North Carolina General Statutes and Title 26 of the North Carolina Administrative
Code. Those interested in filing may access additional information regarding the requirements for filing a
Petition and Petition forms at the OAH website or by calling the OAH Clerk's Office at [phone].
A party filing a Petition shall serve a copy of the Petition on the Department of Environmental Quality's
Office of General Counsel at 1601 Mail Service Center, Raleigh, NC 27699-1601. If the party filing the
Petition is not the Permittee, then the party shall also serve the Permittee pursuant to G.S. 15013-23(a).
If you need any additional information concerning this certification, please contact Leah Parente at
[phone] or leah.paremc&deq.nc.gov.
Sincerely,
DocuSigned by:
TUVV& WO
D1043082680C483...
Richard E. Rogers, Jr., Director
Division of Water Resources
cc: Wake County Health Department (Electronic Copy)
Raleigh Regional Office, Water Quality Regional Operations Section (Electronic Copy)
Laserfiche File (Electronic Copy)
Digital Permit Archive (Electronic Copy)

ATTACHMENT A — LIMITATIONS AND MONITORING REQUIREMENTS
City of Raleigh
Certification Date: August 23, 2023
Permit Number: WQ0002708 Version: 4.2
EFFLUENT CHARACTERISTICS
EFFLUENT LIMITS
MONITORING REQUIREMENTS'
PCS
Code
Parameter Description
Units of
Measure
Monthly
Average
Monthly
Geometric Mean
Daily Minimum
Daily Maximum
Measurement
Frequency
Sample
Type
01002
Arsenic, Total (as As)
µg/L
Monthly
Grab
00310
BOD, 5-Day (20 °C)
mg/L
Monthly
Grab
00916
Calcium, Total (as Ca)
mg/L
Monthly
Grab
00940
Chloride (as Cl)
mg/L
3 x Year 2
Grab
50060
Chlorine, Total Residual
mg/L
Weekly
Grab
31616
Coliform, Fecal MF, M-FC Broth, 44.5 °C
#/100 mL
Monthly 3
Grab
50050
Flow, in Conduit or thru Treatment Plant
GPD
662,885
Continuous
Recorder
01045
Iron, Total (as Fe)
µg/L
Monthly
Grab
00927
Magnesium, Total (as Mg)
mg/L
Monthly
Grab
01055
Manganese, Total (as MnO
µg/L
Monthly
Grab
00600
Nitrogen, Total (as N)
mg/L
Monthly 4
Grab
00400
pH
su
Weekly
Grab
00665
Phosphorus, Total (as P)
mg/L
Monthly
Grab
00931
Sodium Adsorption Ratio
Ratio
Monthly
Calculated
00929
Sodium, Total (as Na)
mg/L
Monthly
Grab
70300
Solids, Total Dissolved — 180 °C
mg/L
3 x Year 1
Grab
00530
Solids, Total Suspended
mg/L
Monthly
Grab
00945
Sulfate, Total (as SO4)
mg/L
Monthly
Grab
1. This facility is not subject to the monitoring requirements listed in the Non -Discharge Effluent Monitoring Policy because the wastewater source for this facility is not domestic.
2. The Permittee shall conduct 3 x Year sampling in March, July, and November.
3. Division has approved the use of the IDEXX Colilert 18 Method for detection of Fecal Coliform when there is no limit for Fecal Coliform.
4. The Division has excluded Total Ammonia Nitrogen, Total Kjeldahl Nitrogen, and Total Nitrate Nitrogen from the required effluent monitoring and replaced them with Total Nitrogen because the
Permittee has shown these constituents are present in low concentrations.
WQ0002708 Version 4.2 Attachment A Page 1 of 1

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ATTACHMENT C — GROUNDWATER MONITORING AND LIMITATIONS
City of Raleigh
Monitoring Wells: MW-13-3, MW-13-8, and MW-13-9
Certification Date: August 23, 2023
Permit Number: WQ0002708 Version: 4.2
GROUNDWATER CHARACTERISTICS
GROUNDWATER STANDARDS
MONITORING REQUIREMENTS
PCS Code
MMMML Parameter Description
Daily Maximum
Frequency Measurement
Sample Type
Footnotes
38576
Acrylamide in Water, Total
0.008
µg/L
3 x Year
Grab
1
01002
Arsenic, Total (as As)
0.01
mg/L
3 x Year
Grab
1
00680
Carbon, Tot Organic (TOC)
mg/L
3 x Year
Grab
1,6
00940
Chloride (as Cl)
250
mg/L
3 x Year
Grab
1
31616
Coliform, Fecal MF, M-FC Broth, 44.5 °C
#/100 mL
3 x Year
Grab
L 8
01045
Iron, Total (as Fe)
0.3
mg/L
3 x Year
Grab
1
01055
Manganese, Total (as Mn)
0.057
mg/L
3 x Year
Grab
1
00620
Nitrogen, Nitrate Total (as N)
10
mg/L
3 x Year
Grab
1
00400
pH
6.5-8.5
su
3 x Year
Grab
1,2
00665
Phosphorus, Total (as P)
mg/L
3 x Year
Grab
1
70300
Solids, Total Dissolved - 180 °C
500
mg/L
3 x Year
Grab
1
00945
Sulfate, Total (as SOa)
250
mg/L
3 x Year
Grab
1
GWVOC
Volatile Compounds (GW)
Present: Yes/No
Annually
Grab
1, 4, 5
82546
Water Level, Distance from measuring point
feet
3 x Year
Calculated
1, 2, 3
1. The Permittee shall conduct 3 x Year monitoring in March, July, and November, and Annual monitoring in November.
2. The Permittee shall measure the water levels prior to purging the wells. The Permittee shall measure the depth to water in each well from the surveyed point on the top of the casing. The Permittee
shall measure pH after purging and prior to sampling for the remaining parameters.
3. The Permittee shall survey the measuring points (top of well casing) of all monitoring wells to provide the relative elevation of the measuring point for each monitoring well. The Permittee shall
survey the measuring points (top of casing) of all monitoring wells relative to a common datum.
WQ0002708 Version 4.2 Attachment C Page 1 of 2

ATTACHMENT C — GROUNDWATER MONITORING AND LIMITATIONS
City of Raleigh
Certification Date: August 23, 2023
Permit Number: WQ0002708 Version: 4.2
Volatile Organic Compounds (VOC) — Analyze by one or more of the following methods:
a. Standard Method 6200 B-2011, PQL at 0.5 �ug/L or less
b. Standard Method 6200 C-2011, PQL at 0.5 gg/L or less
C. SW-846 Method 8021 B, Low Concentration, PQL at 0.5 gg/L or less
d. SW-846 Method 8260 D, Low Concentration, PQL at 0.5 gg/L or less
e. Another method with prior approval by the Water Quality Permitting Section Chief
Any method used shall meet the following qualifications:
a. A Division -certified laboratory shall run any method used.
b. The method used shall include all the constituents listed in Table 6200:I of Standard Methods.
c. The method used shall provide a PQL of 0.5 gg/L or less supported by laboratory proficiency studies as required by the Division's Laboratory Certification Branch. A Division -certified
laboratory shall qualify (estimate) and report any constituents detected above the MDL but below the PQL of 0.5 �ug/L.
5. If monitoring detects any volatile organic compounds (VOC), then the Permiee shall immediately contact the Raleigh Regional Office supervisor, telephone number [phone], for further
instructions regarding any additional follow-up analyses required.
6. If TOC monitoring detects concentrations greater than 10 mg/L in any downgradient monitoring well, the Permiee shall conduct additional sampling and analysis to identify the individual
constituents comprising this TOC concentration. If the TOC concentration as measured in the background monitor well exceeds 10 mg/L, this concentration shall represent the naturally occurring
TOC concentration. Any exceedances of this naturally occurring TOC concentration in the downgradient wells are subject to additional sampling and analysis as described above.
7. The Permiee shall report monitoring well data on Compliance Monitoring Forms (GW-59s) consistent with the nomenclature and location information provided in this attachment.
8. The Division has approved the use of the IDEXX Colilert 18 Method for detection of Fecal Coliform when there is no limit for Fecal Coliform.
WQ0002708 Version 4.2 Attachment C Page 2 of 2