NC0090077_Fact Sheet_20221007

Fact Sheet
NPDES Permit No. NCO090077
Permit Writer/Email Contact: Derek Denard/[e-mail]
Date: 070ct2022
Division/Branch: NC Division of Water Resources/Water Quality Permitting Section
Compliance&Expediated Permitting Branch
Permitting Action:
❑ Renewal
❑ Renewal with Expansion
® New Discharge
❑ Modification(Fact Sheet should be tailored to mod request)
See Permit Application Attachments: A_NC0090077_Application_20220114_39p
B_NCO090077_More Information(Received)_20220405_10p
C NC0090077 More Informatio(Received)_20220429_839p
Complete applicable sections below. If not applicable, enter NA.
1. Basic Facility Information
Facility Information
Applicant/Facility Name: Charlotte Water/Irwin Creek Tributary to Remount Road Project—
CPM 40-20-049
Applicant Address: 5100 Brookshire Boulevard, Charlotte,NC 28216
Facility Address: 2701 Toomey Avenue, Charlotte,NC 28203
Permitted Flow: 0.144 MGD
Facility Type/Waste: Construction dewatering/Groundwater remediation
Facility Class: Grade I Physical Chemical Water Pollution Control System
Treatment Units: See below
Pretreatment Program(Y/N) No
County: Mecklenburg
Region Mooresville
Briefly describe the proposed permitting action and facility background: Charlotte Water[5100
Brookshire Boulevard, Charlotte,NC 282161 has requested a new permit NCO090077 for its Irwin Creek
Tributary to Remount Rd Sewer Project in Mecklenburg County. This permitted facility discharges
treated construction dewatering groundwater to Irwin Creek in the Catawba River Basin. Some of the
parameters in the permit are water quality limited. This discharge may affect future allocations in this
Page 1 of 15

segment of Irwin Creek. The treatment units are for operation of a 0.144 MGD construction dewatering
and groundwater remediation system consisting of,but not limited to;
• a surge tank for flow equalization and settle
• a 1,100-gallon surge tank
• two (2)parallel particle filters
• two (2)metal exchange vessels(HS-250 media resin)
• two (2) 1,000-pound carbon filters(in series)that utilize virgin coconut carbon 32
• a flow totalizer
• an effluent sample port
• an effluent pipe discharging to the city stormwater collection system
2. Receiving Waterbody Information:
Receiving Waterbody Information
Outfalls/Receiving Outfalls 001 & 002/ UT to Irwin Creels
Stream(s):
Stream Segment: 11-137-1
Stream Classification: C
Drainage Area(mi2): --
Summer 7Q 10 (cfs) 0
Winter 7Q 10 (cfs): 0
30Q2 (cfs): 0
Average Flow(cfs): 0
IWC (%effluent): 100
303(d) Impaired for Fish Community&Benthos (Nar,AL,FW),Exceeding
listed/parameter: Criteria; Fair,Poor or Severe Bioclassification. See Attachments D and E.
Subject to Statewide Mercury TMDL, 9/13/2021:
TMDL/parameter: https://deq.nc.gov/media/4665/download
Fecal Coliform Total Maximum Daily Load for the Irwin,McAlpine,Little
Sugar and Sugar Creek Watersheds,Mecklenburg County, 3/28/2002:
https:Hdeq.nc.gov/media/4642/download
Total Maximum Daily Loads (TMDLs)for Turbidity in Long Creek,
McAlpine Creek, Sugar Creek,Little Sugar Creek, Irwin Creek,Henry Fork,
and Mud Creek in North Carolina,2/8/2005:
htlps://deq.nc.gov/media/4640/download
McAlpine,Little Sugar, and Irwin Creek DO TMDL,2/5/1996:
https:Hdeq.nc.gov/media/4645/download
Basin/Sub-basin/HUC: Catawba/03-08-34/030501030101
USGS Topo Quad: Charlotte West,NC
Page 2 of 15

3. Effluent Data Summary
Not Applicable. This is a new discharge Effluent data
4. Instream Data Summary
Instream monitoring may be required in certain situations, for example: 1)to verify model predictions
when model results for instream DO are within 1 mg/1 of instream standard at full permitted flow;2)to
verify model predictions for outfall diffuser; 3)to provide data for future TMDL;4)based on other
instream concerns. Instream monitoring may be conducted by the Permittee, and there are also
Monitoring Coalitions established in several basins that conduct instream sampling for the Permittee(in
which case instream monitoring is waived in the permit as long as coalition membership is maintained).
If applicable, summarize any instream data and what instream monitoring will be proposed for this
permit action:No instream monitoring is proposed.
Is this facility a member of a Monitoring Coalition with waived instream monitoring(YIN):NA.
Name of Monitoring Coalition:NA.
5. Compliance Summary
Summarize the compliance record with permit effluent limits(past 5 years):New permit.NA
Summarize the compliance record with aquatic toxicity test limits and any second species test results
(past 5 years): New permit.NA
Summarize the results from the most recent compliance. inspection:New permit.NA
6. Water Quality-Based Effluent Limitations (WQBELs)
Dilution and Mixing
In accordance with 15A NCAC 213.0206,the following streamflows are used for dilution considerations
for development of WQBELs: 1 Q 10 streamflow(acute Aquatic Life); 7Q 10 streamflow(chronic Aquatic
Life; non-carcinogen HH); 30Q2 streamflow(aesthetics); annual average flow(carcinogen,HH).
If applicable, describe any other dilution factors considered(e.g., based on CORMIX model results):NA.
If applicable, describe any mixing zones established in accordance with 15A NCAC 2B.0204(b):NA.
Oxygen-Consuming Waste Limitations
Limitations for oxygen-consuming waste(e.g.,BOD) are generally based on water quality modeling to
ensure protection of the instream dissolved oxygen(DO)water quality standard. Secondary TBEL limits
(e.g.,BOD=30 mg/1 for Municipals)may be appropriate if deemed more stringent based on dilution and
model results.
If permit limits are more stringent than TBELs, describe how limits were developed:NA.
Page 3 of 15

Ammonia and Total Residual Chlorine Limitations
Limitations for ammonia are based on protection of aquatic life utilizing an ammonia chronic criterion of
1.0 mg/1(summer)and 1.8 mg/l (winter). Acute ammonia limits are derived from chronic criteria,
utilizing a multiplication factor of 3 for Municipals and a multiplication factor of 5 for Non-Municipals.
Limitations for Total Residual Chlorine(TRC)are based on the NC water quality standard for protection
of aquatic life(17 ug/1) and capped at 28 ug/1(acute impacts). Due to analytical issues, all TRC values
reported below 50 ug/1 are considered compliant with their permit limit.
Describe any proposed changes to ammonia and/or TRC limits for this permit renewal: Due to detection
in groundwater, a monthly average limit of 1.0 mg/L(chronic criterion)and a daily maximum limit of 5.0
mg/L(acute)will be included for Ammonia. Winter ammonia limits will not be applied. See Attachment
F NC009007 WLA NH3 TRC Fecal_202207191p.
Reasonable Potential Analysis(RPA) for Toxicants
If applicable, conduct RPA analysis and complete information below.
The need for toxicant limits is based upon a demonstration of reasonable potential to exceed water quality
standards,a statistical evaluation that is conducted during every permit renewal utilizing the most recent
effluent data for each outfall. The RPA is conducted in accordance with 40 CFR 122.44 (d) (i). The NC
RPA procedure utilizes the following: 1) 95%Confidence Level/95%Probability;2) assumption of zero
background; 3)use of detection limit for"less than"values; and 4) streamflows used for dilution
consideration based on 15A NCAC 213.0206. Effective April 6, 2016,NC began implementation of
dissolved metals criteria in the RPA process in accordance with guidance titled NPDES Implementation of
Instream Dissolved Metals Standards, dated June 10, 2016.
A reasonable potential analysis was conducted using groundwater toxicant data that would be
representative of influent flow to the treatment system. This data was collected between Marl996 and
Feb2020. Pollutants of concern included toxicants with positive detections and associated water quality
standards/criteria. Based on this analysis,the following permitting actions are proposed for this permit:
Since data ranged over a wide period of time and more current data(Feb2020)was limited to
three (3) samples,monitoring and limits were assigned to all pollutants of concern that were
detected in groundwater. Parameters were added for pollutants that were present in soil samples.
See following attached RPA sheets for details:
G_NC0090077 GENERIC RPA_13p
H_NC0090077 FW RPA_16p
I_Diss metals Implementation-Fact Sheet Info 5-16-16(Grzyb,Julie)_20220727_4p
Toxicity Testing Limitations
Permit limits and monitoring requirements for Whole Effluent Toxicity(WET)have been established in
accordance with Division guidance(per WET Memo, 8/2/1999). Per WET guidance, all NPDES permits
issued to Major facilities or any facility discharging"complex"wastewater(contains anything other than
domestic waste)will contain appropriate WET limits and monitoring requirements,with several
exceptions. The State has received prior EPA approval to use an Alternative WET Test Procedure in
NPDES permits,using single concentration screening tests,with multiple dilution follow-up upon a test
failure.
Describe proposed toxicity test requirement: Whole Effluent Toxicity(WET) -Acute,Monitor Only;
Monthly(Pimephales promelas)48-hour static test. [See Section A. (2)].Acute toxicity(monitoring only)
Page 4 of 15

is recommended because the final effluent is to be polished with activated carbon,historically rendering
effluent too clean to prevent WET-test failure. [WQBEL.No toxics in toxic amounts. 15A NCAC
2B.0200 and 15A NCAC 2B.0500 (not limited).]
Mercury Statewide TMDL Evaluation
There is a statewide TMDL for mercury approved by EPA in 2012. The TMDL target was to comply with
EPA's mercury fish tissue criteria(0.3 mg/kg)for human health protection. The TMDL established a
wasteload allocation for point sources of 37 kg/year(81 lb/year), and is applicable to municipals and
industrial facilities with known mercury discharges. Given the small contribution of mercury from point
sources(-2%of total load),the TMDL emphasizes mercury minimization plans(MMPs) for point source
control.Municipal facilities>2 MGD and discharging quantifiable levels of mercury(>1 ng/1)will
receive an MMP requirement. Industrials are evaluated on a case-by-case basis,depending if mercury is a
pollutant of concern. Effluent limits may also be added if annual average effluent concentrations exceed
the WQBEL value(based on the NC WQS of 12 ng/1)and/or if any individual value exceeds a TBEL
value of 47 ng/1
Describe proposed permit actions based on mercury evaluation: Construction dewatering/groundwater
remediations. Mercury is present.
Other TMDL/Nutrient Management Strategy Considerations
If applicable, describe any other TMDLs/Nutrient Management Strategies and their implementation
within this permit: NA.
Other WQBEL Considerations
If applicable, describe any other parameters of concern evaluated for WQBELs: See attached RPA
spreadsheets and Section 12 of this Fact Sheet for parameters of concern evaluated for WQBELs.
If applicable, describe any special actions (HQW or ORW) this receiving stream and classification shall
comply with in order to protect the designated waterbody:NA.
If applicable, describe any compliance schedules proposed for this permit renewal in accordance with
15A NCAC 2IL 0107(c)(2)(B), 40CFR 122.47, and EPA May 2007 Memo:NA.
If applicable, describe any water quality standards variances proposed in accordance with NCGS 143-
215.3(e) and 15A NCAC 2B.0226 for this permit renewal: NA.
7. Technology-Based Effluent Limitations (TBELs)
Industrials(if not applicable, delete and skip to next Section)
Describe what this facility produces: construction dewatering/groundwater remediation which includes a
pre-regulatory landfill, ash deposal from an incinerator,DSCA sites (dry cleaners), a hard chrome
electroplating, and facility(Dynatech Industries, Inc.),AST&UST incidents.
A regional office staff report(see Attachment I)by Edward Watson,Hydrogeologist,provided a
description of facilities that have contaminated groundwater in the area as follows:
The Pre-Regulatory Landfill has been assigned 1NSB site#NONCD000807. The site is listed as
a Superfund site. There is observed C&D type material exposed in the wooded area of the
property behind the parking lot. Also,there is documentation of 55-gallon drums containing
Page 5 of 15

Lead and Chromium waste on the property. The Site Summary Report for July 21,2021 prepared
by Schnabel Engineering South, P. C. of Greensboro N.C. IHSB DOC# SF_F
NONCD0000807 07-21-2010 IHS LR.
The information for the nearby sites indicates the former presence of several Gas Stations and
Automotive Service facilities with former USTs, several Former Dry Cleaning facilities, a
Construction Company, and the Former Pre-regulatory Southside Ash Landfill.
A review of the DWM Site Locator Web Browser Tool, indicates several potential sources of
contaminates near and around the subject site.A documents review revealed that an unknown
quantity of Hazardous waste was stored within the former Industrial Crankshaft&Engineering
Co,Inc. facility d/b/a/Dynatech Industries Site located at 2213 Toomey Ave., Charlotte. This
facility is listed as a Superf ind/Inactive Section facility within permit#NCD9811014517.
Assessment documents were reviewed associated with these former facilities. The documents
include GW Chemistry data that was available on the Division of Waste Management Site
Locator Tool.
Many of these facilities have received NFA status from DWM for a variety of reasons.
GW analytical data from existing monitor wells indicate petroleum constituents present at levels
above 2L or PSRG Soil Standards.
There are no water supply wells found to be located on the property.
List the federal effluent limitations guideline (ELG)for this facility:None are directly applicable.
If the ELG is based on production or flow, document how the average production/flow value was
calculated: The ELG is based on a flow and limits are in concentration(mg/L,ppm). The permitted flow
will be 0.144 MGD.
For ELG limits, document the calculations used to develop TBEL limits: The limits in the Table below are
based the effluent guidelines as indicated. See BPJ discussion below.
Table. TBEL Development
TBEL TBEL Acute Chronic
Daily Monthly WQBEL WQBEL Daily Monthly
Maximu Average or or Maximum Average
Pollutant UoM ELG m Limit Limit Criteria Criteria Limit Limit
413 6-9
pH SU 444 6-9 6-9 6-9
445 6-9
BOD mg/L 445 140 37 NA NA 45 * 30*
433 60 31
TSS mg/L 444 113 34.8 NA NA 45 * 30 *
445 88 27
Ammonia mg/L 445 10 4.9 5.0 1.0 5.0 1.0
(as N)
Oil& 419 15.0
Grease mg/L (N) (N) 20 mg/L 15 mg/L
433 52 26
Page 6 of 15

444 84 72
Arsenic µg/L 340 150 340 150
445 1,100 540
413 1200 700
Cadmium µg/L 433 690 260 3.24 0.59 3.24 0.59
444 71 26
Chromium µg/L NA NA NA 905.1 117.7 905.1 117.7
(III)
Chromium µg/L NA NA NA 16 11 16 11
(IV)
413 7000 4000
Chromium, /L, 433 2770 1710 Monitor Monitor Monitor& Monitor&
Total µg 444 25 14 &Report &Report Report Report
445 1,100 460
413 4500 2700
Copper µg/L 433 3380 2070 10.47 7.88 10.47 7.88
444 23 14
Cyanide, 413 1200 700
Total µg/I' 22 5 22 5
433 1200 650
413 600 400
Lead µg/L 433 690 430 75.49 2.94 75.49 2.94
444 57 32
413 4100 2600
Nickel µg/L 335.2 37.2 335.2 37.2
433 3980 2380
Mercury ng/L 444 2300 1300 12 12 12 12
433 430 240
Silver µg/L 0.30 0.06 0.30 0.06
444 13 8
Titanium µg/L 444 60 22 NA NA No No
Monitoring Monitoring
413 4200 2600
Zinc µg/L 444 82 54 125.7 126.7 125.7 125.7
445 200 110
a-Terpineol µg/L 445 33 16 NA NA 33 16
Aniline µg/L 445 24 15 NA NA 24 15
Page 7 of 15

Benzoic µg/L 445 119 71 NA 9,000 NC 119 71
acid
Naphthalene µg/L 445 59 22 NA 12 NC 12 12
p-Cresol µg/L 445 24 14 NA NA 24 14
Phenol µg/L 445 26 15 NA NA 26 15
Pyridine µg/L 445 72 25 NA 1.300 NC 72 25
Footnotes:
413—Electroplating Point Source Category, CFR§413.14—Pretreatment standards for existing sources -
Subpart A-Common Metals Facilities Discharging 38,000 Liters or More Per Day PSES
Limitations
419—Petroleum Refining,CFR§419—Contaminated runoff
433—Metal Finishing Point Source Category, CFR§433.13—Subpart A(BPT)
444—Waste Combustors Point Source Category(NSPS),CFR§444.17—Subpart A-Commercial
Hazardous Waste Combustor
445—Landfills Point Source Category,CFR§445.11/§445.21; Subpart A—RCRA Subtitle C Hazardous
Waste Landfill(BPT) and Subpart B—RCRA Subtitle D Non-Hazardous Waste Landfill(BPT)
* —Secondary treatment standards/40 CFR 133 / 15A NCAC 2B .0406
NC—North Carolina In-Stream Target Values for Surface Waters. Established per language in
15A NCAC 02B .0202 & .0208.
(N)—Narrative Standard
If any limits are based on best professional judgement(BPJ), describe development: 40 CFR 125.3(c)(2)
provides that,where there are no applicable EPA effluent guidelines,permit writers have the authority to
develop technology-based limitations on a case-by-case basis under section 402(a)(1)(B)of the Clean
Water Act. The sewer project is in close proximity to a pre-regulatory landfill. The most stringent ELG
from 40 CFR 445 will be applied to treatment of construction dewatering.
Document any TBELs that are more stringent than WQBELs:
Oil&Grease has a narrative standard found in 15A NCAC 2B .0200. There are no numerical values set
for Oil&Grease for WQBELSs.
Document any TBELs that are less stringent than previous permit:NA,new permit.
8. Antidegradation Review (New/Expanding Discharge):
The objective of an antidegradation review is to ensure that a new or increased pollutant loading will not
degrade water quality. Permitting actions for new or expanding discharges require an antidegradation
review in accordance with 15A NCAC 2B.0201. Each applicant for a new/expanding NPDES permit
must document an effort to consider non-discharge alternatives per 15A NCAC 2H.0105(c)(2). In all
cases, existing instream water uses and the level of water quality necessary to protect the existing use is
maintained and protected.
If applicable, describe the results of the antidegradation review, including the Engineering Alternatives
Analysis (EAA)and any water quality modeling results: The EAA was reviewed on 06/10/2022. The
following alternatives were cost prohibitive:
Page 8 of 15

• Connection to POTW—Prohibited by sewer use ordinance.
• Connection to Private WTP- $6,603,000.
• Land Application—$70,537,000. Due to limited land availability this alternative is technically
infeasible.
• Infiltration Galleries—$30,397,000. Due to limited land availability this alternative is technically
infeasible.
• Closed-Loop Groundwater Remediation Wells—$10,507,000. Due to limited land availability
this alternative is technically infeasible.
The cost for surface water discharge(NPDES)was estimated to be $336,000.
9. Antibacksliding Review:
Sections 402(o)(2)and 303(d)(4)of the CWA and federal regulations at 40 CFR 122.44(1)prohibit
backsliding of effluent limitations in NPDES permits. These provisions require effluent limitations in a
reissued permit to be as stringent as those in the previous permit,with some exceptions where limitations
may be relaxed(e.g.,based on new information, increases in production may warrant less stringent TBEL
limits, or WQBELs may be less stringent based on updated RPA or dilution).
Are any effluent limitations less stringent than previous permit(YES/NO):NA,new permit.
If YES, confirm that antibackslidingprovisions are not violated:NA.
10. Monitoring Requirements
Monitoring frequencies for NPDES permitting are established in accordance with the following
regulations and guidance: 1) State Regulation for Surface Water Monitoring, 15A NCAC 2B.0500; 2)
NPDES Guidance,Monitoring Frequency for Toxic Substances(7/15/2010 Memo); 3)NPDES Guidance,
Reduced Monitoring Frequencies for Facilities with Superior Compliance(10/22/2012 Memo);4)Best
Professional Judgement(BPJ). Per US EPA(Interim Guidance, 1996),monitoring requirements are not
considered effluent limitations under Section 402(o)of the Clean Water Act, and therefore anti-
backsliding prohibitions would not be triggered by reductions in monitoring frequencies.
For instream monitoring,refer to Section 4.
11. Electronic Reporting Requirements
The US EPA NPDES Electronic Reporting Rule was finalized on December 21,2015. Effective
December 21,2016,NPDES regulated facilities are required to submit Discharge Monitoring Reports
(DMRs) electronically. Effective December 21,2020,NPDES regulated facilities will be required to
submit additional NPDES reports electronically. This permit contains the requirements for electronic
reporting,consistent with Federal requirements.
Page 9 of 15

12. Summary of Proposed Permitting Actions:
A. Table. Current Permit Conditions and Proposed Changes—Outfalis 001 &002
Parameter Proposed Condition Basis for Condition/Change
Flow MA 0.144 MGD 15A NCAC 213 .0505
pH 6—9 SU WQBEL State WQ Narrative standard, 15A NCAC 02B .0200.
POC for Petroleum UST&AST incidents,Landfills,Waste
Combustors,and Metal Finishing.
Turbidity Monitor&Report. WQBEL. State WQ Narrative Standard, 15A NCAC 02B .0200
Added footnote for TMDL for Turbidity in Long Creek,McAlpine Creek, Sugar
Narrative Standard for Creek,Little Sugar Creek,Irwin Creek,Henry Fork,and Mud
instream 50 NTU. Creek in North Carolina,2/8/2005
BOD MA 30.0 mg/1 TBEL. Secondary treatment standards/40 CFR 133/ 15A NCAC
DM 45.0 mg/1 2B .0406
Detected in groundwater samples.POC for Landfills.
Total Suspended Solids MA 30.0 mg/1 Secondary treatment standards/40 CFR 133/ 15A NCAC 2B
(TSS) DM 45.0 mg/1 .0406
Detected in groundwater samples.POC for Landfills,Petroleum
UST&AST incidents,Waste Combustors,and Metal Finishing.
Ammonia(as N) MA 1.0 mg/L WQBEL.Based on protection of State WQ criteria. 15A NCAC
DM 5.0 mg/L 2B.0200
Detected in groundwater samples.POC for Landfills.
Oil and Grease MA 15.0 mg/1 WQBEL. State WQ Narrative Standard, 15A NCAC 02B .0200
[EPA Method 1664 SGT- DM 20.0 mg/1 BPJ for TBEL.40 CFR 125.3(c)(2)on a case-by-case basis under
HEM] section 402(a)(1)(B)CWA.
POC for Petroleum UST&AST incidents,Landfills,Metal
Finishing.
Arsenic,Total(as As) MA 10 µg/L WQBEL. State WQ Standard, 15A NCAC 02B .0200
DM 340 µg/L
POC found in found in TCLP, Soil,and/or Ash samples.POC for
Landfills,Waste Combustors.RCRA 8 Metal.
Barium,Total(as Ba) MA 21,000 µg/L NC In-Stream Target Values for Surface Waters,Established per
DM 21,000 µg/L language in 15A NCAC 02B .0202& .0208.
Detected in groundwater samples,TCLP,Soil,and/or Ash
samples.RCRA 8 Metal.
Bromide(as Br)(µg/L) Monitor&Report POC found in groundwater samples.
Cadmium,Total(as Cd) MA 0.59 µg/L WQBEL. State WQ standard, 15A NCAC 2B .0200
DM 3.24 µg/L
POC found in TCLP, Soil,and/or Ash samples.POC for
Electroplating,Metal Finishing,and Waste Combustors.RCRA 8
Metal.
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Chloride,(as Cl) MA 230 mg/L WQBEL. State WQ standard, 15A NCAC 2B .0200
DM 230 mg/L
Detected in groundwater samples.
Chromium,Trivalent(as Cr) MA 117.7 µg/L WQBEL. State WQ standard, 15A NCAC 2B .0200
DM 905.1 µg/L
Total Chromium detected in groundwater samples,TCLP, Soil,
and/or Ash samples.
Chromium,Hexavalent(as MA 11 µg/L WQBEL. State WQ standard, 15A NCAC 2B .0200
Cr) DM 16 µg/L
Total Chromium detected in groundwater samples,TCLP, Soil,
and/or Ash samples.
Chromium,Total(as Cr) Monitor&Report WQBEL. State WQ standard, 15A NCAC 213.0200
Detected in groundwater samples,TCLP, Soil,and/or Ash
samples.POC for Landfills,Electroplating,Metal Finishing,and
Waste Combustors.RCRA 8 Metal.
Copper,Total(as Cu) MA 7.88 µg/L WQBEL. State WQ standard, 15A NCAC 2B .0200
DM 10.47 µg/L
POC for Metal Finishing,Electroplating,and Waste Combustors.
Cyanide,Total(as Cn) MA 5.0 µg/L WQBEL. State WQ standard, 15A NCAC 2B .0200
DM 22.0 µg/L
Detected in groundwater samples.POC for Electroplating and
Metal Finishing.
Fluoride,Total(as F) MA 1,800 µg/L WQBEL. State WQ standard, 15A NCAC 2B .0200
DM 1,800 µg/L
Detected in groundwater samples.
Lead,Total(as Pb) MA 2.94 µg/L WQBEL. State WQ standard, 15A NCAC 2B .0200
DM 75.49 µg/L
Detected in groundwater samples,TCLP, Soil,and/or Ash
samples.POC for UST&AST incidents,Electroplating,Metal
Finishing,and Waste Combustors.RCRA 8 Metal.
Mercury,Total(as Hg) MA 12.0 ng/L WQBEL. State WQ standard, 15A NCAC 2B .0200
DM 12.0 ng/L
Detected in TCLP, Soil,and/or Ash samples.POC for Waste
Combustors.RCRA 8 Metal.
Nickel,Total(as Ni) MA 37.2 µg/L WQBEL. State WQ standard, 15A NCAC 2B .0200
DM 335.2 µg/L
POC for Electroplating and Metal Finishing
Selenium,Total(as Se) MA 5.0 µg/L WQBEL. State WQ standard, 15A NCAC 2B .0200
DM 56.0 µg/L
RCRA 8 Metal.
Silver,Total(as Ag) MA 0.06 µg/L WQBEL. State WQ standard, 15A NCAC 2B .0200
DM 0.30 µg/L
POC for Waste Combustors and Metal Finishing.RCRA 8 Metal
Sulfate,Total(as SO4) Monitor&Report Detected in groundwater samples.
Zinc,Total(as Zn) MA 125.7 µg/L WQBEL. State WQ standard, 15A NCAC 2B .0200
DM 125.7 µg/L
POC for Landfills,Waste Combustors,Electroplating,and Metal
Finishing.
Page 11 of 15

Hardness—Total as Monitor&Report WQBEL. State WQ standard, 15A NCAC 2B .0200
[CaCO3 or(Ca+Mg)]
Needed for calculation of hardness-dependent metals.For more
information see Attachment G.
Nitrite+Nitrate,Total(as Monitor&Report Detected in groundwater samples.
N)
Monitoring due to presence of Nutrients in groundwater samples.
Nitrogen,Total(TN) Monitor&Report WQBEL. Required to comply with NC chl-a WQS. 15A NCAC
213.0200.
Monitoring due to presence of Nutrients in groundwater samples.
Phosphorus,Total(TP) Monitor&Report WQBEL. Required to comply with NC chl-a WQS. 15A NCAC
213.0200.
Detected in groundwater samples,TCLP, Soil,and/or Ash
samples.
1,2-Dichloroethane(1,2- MA 650 µg/L EPA National Recommended Water Quality Criteria for Aquatic
DCA) DM 650 µg/L Life&Human Health.
POC for Petroleum UST&AST incidents.
Acenaphthene MA 60 µg/L NC In-Stream Target Values for Surface Waters,Established per
DM 60 µg/L language in 15A NCAC 02B .0202& .0208.
Detected in TCLP sample.
alpha-Terpineol MA 16 µg/L BPJ for TBEL.40 CFR 125.3(c)(2)on a case-by-case basis under
DM 33 µg/L section 402(a)(1)(B)CWA.
POC for Landfill TBELs.
Aniline(µg/L) MA 15 µg/L BPJ for TBEL.40 CFR 125.3(c)(2)on a case-by-case basis under
DM 24 µg/L section 402(a)(1)(B)CWA.
POC for Landfill TBELs.
Anthracene MA 0.05 µg/L NC In-Stream Target Values for Surface Waters,Established per
DM 0.05 µg/L language in 15A NCAC 02B .0202&.0208.
Detected in TCLP sample.
Benzene MA 51 µg/L WQBEL. State WQ standard, 15A NCAC 2B .0200
DM 51 µg/L,
POC for Petroleum UST&AST incidents.WQBEL. State WQ
Standard, 15A NCAC 02B .0200
Benzo(g,h,i)perylene Monitor&Report Detected in TCLP sample.
Benzoic Acids,Total MA 71 µg/L BPJ for TBEL.40 CFR 125.3(c)(2)on a case-by-case basis under
DM 119 µg/L section 402(a)(1)(B)CWA.
POC for Landfill TBELs.
Chlorobenzene MA 140 µg/L NC In-Stream Target Values for Surface Waters,Established per
DM 140 µg/L language in 15A NCAC 02B .0202& .0208.
Detected in groundwater samples.
Page 12 of 15

Ethyl Benzene MA 97 µg/L NC In-Stream Target Values for Surface Waters,Established per
DM 97 µg/L language in 15A NCAC 02B .0202& .0208.
POC for Petroleum UST&AST incidents.
Fluoranthene MA 0.11 µg/L NC In-Stream Target Values for Surface Waters,Established per
DM 0.11 µg/L language in 15A NCAC 02B .0202&.0208.
Detected in TCLP sample.
Fluorene MA 30 µg/L NC In-Stream Target Values for Surface Waters,Established per
DM 30 µg/L language in 15A NCAC 02B .0202& .0208.
Detected in TCLP sample.
Methyl Tert-Butyl Ether MA 1,500 µg/L NC In-Stream Target Values for Surface Waters,Established per
(MTBE) DM 1,500 µg/L language in 15A NCAC 02B .0202& .0208.
POC for Petroleum UST&AST incidents.
Naphthalene MA 12 µg/L NC In-Stream Target Values for Surface Waters,Established per
DM 12 µg/L language in 15A NCAC 02B .0202& .0208.
POC for Landfill,and Petroleum UST&AST incidents.
p-Cresol MA 14 µg/L BPJ for TBEL.40 CFR 125.3(c)(2)on a case-by-case basis under
DM 14 µg/L section 402(a)(1)(B)CWA.
POC for Landfill TBELs.
Phenanthrene MA 0.7 µg/L NC In-Stream Target Values for Surface Waters,Established per
DM 0.7 µg/L language in 15A NCAC 02B .0202& .0208.
Detected in TCLP sample.
Phenol MA 15 µg/L BPJ for TBEL.40 CFR 125.3(c)(2)on a case-by-case basis under
DM 26 µg/L section 402(a)(1)(B)CWA.
POC for Landfill TBELs.
Phenolics,Total MA 300 µg/L WQBEL. State WQ Narrative Standard, 15A NCAC 02B .0200,
Recoverable DM 300 µg/L Aesthetic narrative standard for taste&odor in fish tissue.Based
on public policy document.
POC for Petroleum UST&AST incidents.
Pyrene MA 30 µg/L EPA National Recommended Water Quality Criteria for Aquatic
DM 30 µg/L Life&Human Health.
Detected in TCLP sample.
Pyridine MA 25 µg/L BPJ for TBEL.40 CFR 125.3(c)(2)on a case-by-case basis under
DM 72 µg/L section 402(a)(1)(B)CWA.
POC for Landfill TBELs.
Tetrachloroethylene(PERC) MA 3.3 µg/L WQBEL. State WQ standard, 15A NCAC 2B .0200
DM 3.3 µg/L
POC for DSCA site(dry cleaner solvent).
Toluene MA 11 µg/L WQBEL. State WQ Standard, 15A NCAC 02B .0200
DM 11 µg/L
Page 13 of 15

POC for Petroleum UST&AST incidents.
Xylenes,Total MA 670 µg/L NC In-Stream Target Values for Surface Waters,Established per
(mix of m+o+p) DM 670 µg/L language in 15A NCAC 02B .0202&.0208.
POC for Petroleum UST&AST incidents.
Polynuclear Aromatic Limit for Total State WQ Standard, 15A NCAC 02B .0200.
Hydrocarbons(PAH),Total MA 0.0311 µg/L
of the following: DM 0.0311 µg/L Detected in TCLP sample.
Benzo(a)anthracene Monitor&Report each
parameter separately
Benzo(a)pyrene and report total as Total
Benzo(b)fluoranthene PAH.
Benzo(k)fluoranthene
Chrysene
Dibenz(a,h)anthracene
Indeno(1,2,3-cd)pyrene
Acute WET test Acute,Monitor Only; WQBEL. No toxics in toxic amounts. 15A NCAC 213.0200 and
Monthly(Pimephales 15A NCAC 213.0500
promelas)48-hour
static test.
Organics,Total Purgeables Monitor&Report 40 CFR 122
(VOCs)
(EPA Method 624.1)
Base Neutrals&Acids Monitor&Report 40 CFR 122
(Semi-VOCs)
(EPA Method 625.1)
Additional Monitoring Add Special Condition G.S. 143-215.1(B)
Requirements for EPA Methods 624
and 625.
Electronic Reporting Add Electronic in accordance with EPA Electronic Reporting Rule 2015.
Reporting Special
Condition
MGD—Million gallons per day,MA—Monthly Average,WA—Weekly Average,DM—Daily Max
POC—Pollutant of Concern
Page 14 of 15

13. Public Notice Schedule:
Permit to Public Notice: 08/14/2022 [See Attachment K]
Per 15A NCAC 211 .0109& .0111, The Division will receive comments for a period of 30 days following
the publication date of the public notice. Any request for a public hearing shall be submitted to the
Director within the 30 days comment period indicating the interest of the party filing such request and the
reasons why a hearing is warranted.
14. Fact Sheet Addendum (if applicable):
Were there any changes made since the Draft Permit was public noticed(Yes/No):Yes.
If Yes, list changes and their basis below:
This final permit includes the following changes from the draft permit:
1. The Acute WET test monitoring Footnote 7 was updated to the following:
Whole Effluent Toxicity(WET): Acute (Pimephales promelas)48-hour static test at 90%,
Monitor Only,Monthly. [See Special Condition A. (2.)].
2. Special Condition A. (2.) for Acute WET testing was updated to include the following sentence:
The effluent concentration at which there may be at no time significant acute mortality is
90%(defined as treatment two in the procedure document).
3. Footnote 8 for EPA Methods 624.1 and 625.1 was updated to include the following clarification:
Monitoring shall include all analytes listed in Condition A. (4.).
15. Fact Sheet Attachments (list in order of reference):
A. NC0090077_Application_20220114_39p,Laserfiche Link:
https://edocs.deq.nc.gov/WaterResources/DocView.aspx?id=2165082&dbid=0&repo=WaterResources
B. NC0090077_More Information(Received)_20220405_10p,Laserfiche Link:
https://edocs.deq.nc.gov/WaterResources/DocView.aspx?id=2271713&dbid=0&repo=WaterResources
C. NC0090077_More Information(Received)_20220429_839p
https://edocs.deq.nc.gov/WaterResources/DocView.aspx?id=2430801&dbid=0&repo=WaterResources
D. NC_2020_Category5_303dlist 37,Laserfiche Link:
E. NC 2020 INTEGRATED REPORT 351
F. NC009007 WLA NH3 TRC Fecal_20220719_lp
G. NC0090077 GENERIC RPA_13p
H. NC0090077 FW RPA_16p
1. Diss metals Implementation-Fact Sheet Info 5-16-16(Grzyb,Julie)_20220727_4p
J. NC0090077_Staff Report_20220214_3p,Laserfiche Link:
https://edocs.deq.nc.gov/WaterResources/DocView.aspx?id=2218463&dbid=0&repo=WaterResources
K. NC0090077_Affidavit_20220816_lp
L. Regional Office Comments_20220801_2p
m M. Aquatic Toxicity Branch Coments_20220809_9p
N. Permittee_Electronic Receipt_2p
Page 15 of 15

NORTH CAROLINA 2022 INTEGRATED REPORT
Lower Catawba Catawba River Basin
AU Name AU Number Classification AU LengthArea AU Units
AU ID Description
Irwin Creek 11-137-1 C 11.8 FW Miles
638 From source to Sugar Creek
2022 Water Quality Assessments
PARAMETER IR CATEGORY CRITERIA STATUS
Turbidity (50 NTU, AL, FW miles) 4i Exceeding Criteria
Water Temperature (322C, AL, LP&CP) 1 Meeting Criteria
Dissolved Oxygen (4 mg/I, AL, FW) 1 Meeting Criteria
pH (6 su, AL, FW) 1 Meeting Criteria
pH (9.0, AL, FW) 1 Meeting Criteria
Fish Community (Nar, AL, FW) 5 Exceeding Criteria
Benthos (Nar, AL, FW) 5 Exceeding Criteria
Fecal Coliform (GM 200/400, REC, FW) 3a Data Inconclusive
Copper Dissolved Acute (4.8 µg/l, AL, SW) 1 Meeting Criteria
Zinc Dissolved Chronic (81 jig/I, AL, SW) 1 Meeting Criteria
Lead Dissolved Chronic (8.1, AL, SW) 1 Meeting Criteria
Total Suspended Solids it
Fecal Coliform (GM 200/400, REC, FW) 4t Exceeding Criteria
McCullough Branch 11-137-7 C 3.1 FW Miles
657 From source to Sugar Creek
2022 Water Quality Assessments
PARAMETER IR CATEGORY CRITERIA STATUS
Benthos (Nar, AL, FW) 5 Exceeding Criteria
6/7/2022 NC 2022 INTEGRATED REPORT-Category 5 Approved by EPA 4/30/2022 Page 353 of 1346

NORTH CAROLINA 2022 303(D) LIST
South Fork Catawba Catawba River Basin
AU Name AU Number Classification AU_LengthArea AU—Units
AU ID Description
Mill Creek 11-129-8-4-( WS-II;HQW 4.6 FW Miles
588 From source to a point 0.5 mile upstream of mouth
PARAMETER IR CATEGORY CRITERIA STATUS REASON FOR RATING 303D YEAR
Benthos(Nar,AL, FW) 5 Exceeding Criteria Fair, Poor or Severe Bioclassification 2010
Catawba River Basin 03050103 Lower Catawba
Sugar Creek 11-137 C 13.7 FW Miles
14110 From Source to NC/SC border
PARAMETER IR CATEGORY CRITERIA STATUS REASON FOR RATING 303D YEAR
Benthos(Nar,AL, FW) 5 Exceeding Criteria Fair, Poor or Severe Bioclassification
Fish Community(Nar,AL, FW) 5 Exceeding Criteria Fair, Poor or Severe Bioclassification
Irwin Creek 11-137-1 C 11 R FW Miles
638 From source to Sugar Creek
PARAMETER IR CATEGORY CRITERIA STATUS REASON FOR RATING 303D YEAR
Fish Community(Nar,AL, FW) 5 Exceeding Criteria Fair, Poor or Severe Bioclassification 2008
Benthos(Nar,AL, FW) 5 Exceeding Criteria Fair, Poor or Severe Bioclassification
McCullough Branch 11-137-7 C 3.1 FW Miles
657 From source to Sugar Creek
PARAMETER IR CATEGORY CRITERIA STATUS REASON FOR RATING 303D YEAR
Benthos(Nar,AL, FW) 5 Exceeding Criteria Fair, Poor or Severe Bioclassification 1998
Little Sugar Creek 11-137-8 C 14.2 FW Miles
14111 From NC 51 to North Carolina-South Carolina State Line
PARAMETER IR CATEGORY CRITERIA STATUS REASON FOR RATING 303D YEAR
Benthos(Nar,AL, FW) 5 Exceeding Criteria Fair, Poor or Severe Bioclassification 1998
Fish Community(Nar,AL, FW) 5 Exceeding Criteria Fair, Poor or Severe Bioclassification 2010
McMullen Creek 11-137-9-5 C 1 FW Miles
675 From source to McAlpine Creek
PARAMETER IR CATEGORY CRITERIA STATUS REASON FOR RATING 303D YEAR
Benthos(Nar,AL, FW) 5 Exceeding Criteria Fair, Poor or Severe Bioclassification
6/7/2022 NC 2022 303d List-Approved by EPA 4/30/2022 Page 36 of 192

IWC Calculations
Facility: Charlotte Water/ Irwin Creek Tributary to Remount Road Project
NC0090077
Prepared By: Derek Denard
Enter Design Flow(MGD): 0.144
Enter s7Q10 (cfs): 0
Enter w7Q10 (cfs): 0
Total Residual Chlorine (TRC) Ammonia (Summer)
Daily Maximum Limit (ug/1) Monthly Average Limit (mg NH3-N/1)
s7Q10 (CFS) 0 s7Q10 (CFS) 0
DESIGN FLOW (MGD) 0.144 DESIGN FLOW (MGD) 0.144
DESIGN FLOW (CFS) 0.2232 DESIGN FLOW (CFS) 0.2232
STREAM STD (UG/L) 17.0 STREAM STD (MG/L) 1.0
Upstream Bkgd (ug/1) 0 Upstream Bkgd (mg/1) 0.22
IWC (%) 100.00 IWC (%) 100.00
Allowable Conc. (ug/1) 17 Allowable Conc. (mg/1) 1.0
Ammonia (Winter)
Monthly Average Limit(mg NH3-N/1)
Fecal Coliform w7Q10 (CFS) 0
Monthly Average Limit: 200/100mI DESIGN FLOW (MGD) 0.144
(If DF >331; Monitor) DESIGN FLOW (CFS) 0.2232
(If DF<331; Limit) STREAM STD (MG/L) 1.8
Dilution Factor(DF) 1.00 Upstream Bkgd (mg/1) 0.22
IWC (%) 100.00
Allowable Conc. (mg/1) 1.8
Total Residual Chlorine
1. Cap Daily Max limit at 28 ug/I to protect for acute toxicity
Ammonia (as NH3-N)
1. If Allowable Conc > 35 mg/I, Monitor Only
2. Monthly Avg limit x 3 =Weekly Avg limit (Municipals); capped at 35 mg/I
3. Monthly Avg limit x 5 = Daily Max limit(Non-Munis); capped at 35 mg/I
4. BAT for Minor Domestics: 2 mg/I (summer) and 4 mg/I (winter)
5. BAT for Major Municipals: 1 mg/I (year-round)
Fecal Coliform
1. Monthly Avg limit x 2 =400/100 ml = Weekly Avg limit (Municipals) = Daily Max limit(Non-Muni)
NPDES Server/Current Versions/WLA; TB 1/16/2009

2018 Generic RPA - 95% Probability/95% Confidence
MAXIMUM DATA POINTS = 58
REQUIRED DATA ENTRY MISSING DATA or ENTRY ERROR
Table 1. Project Information Table 2. Parameters of Concern
❑CHECK IF HQW OR ORW Name Type Chronic Modifier Acute PQL Units
Facility Name Irwin Creek Tributary to Remount Road Project Par01 Benzene C 51 HH 1 Ng/L
WWTP/WTP Class PC-1 Par02 Toluene NC 11 FW 1 Ng/L
NPDES Permit NCO090077 Par03 Ethylbenzene NC 97 FW 1 Ng/L
Outfall 001 Par04 Xylene NC 670 FW 1 Ng/L
Flow,Qw(MGD) 0.144 Par05 MTBE C 1500 HH 5 1 Ng/L
Receiving Stream LIT to Irwin Creek Par06 1,2-Dichoroethane(1,2 DCA) C 650 HH 1 Ng/L
Stream Class C Par07 Tetrachloroethylene(PERC) C 3.3 HH 1 Ng/L
HUC Number 30501030101 Par08 Napthalene NC 12 FW 2 Ng/L
7Q10s(cfs) 0.00 Par09 alpha-Terpineol Ng/L
7Q10w(cfs) 0.00 Par10 Benzoic Acids NC 9000 FW 50 Ng/L
30Q2(cfs) 0.00 Par11 Pyridine NC 1300 HH Ng/L
QA(cfs) 0.00 Par12 Polynuclear Aromatic Hydrocarbons(PAH) C 0.0311 HH Ng/L
1Q10s(cfs) 0.00 Par13 Acenaphthene NC 60 FW 10 Ng/L
Data Source(s) Par14 Anthracene NC 0.05 FW 10 Ng/L
❑CHECK TO APPLY MODEL Par15 Benzo(g,h,i)perylene 10 Ng/L
Par16 Fluoranthene NC 0.11 FW 10 Ng/L
Par17 Fluorene NC 30 FW 12 Ng/L
Par18 Phenanthrene NC 0.7 FW 10 Ng/L
Par19 Pyrene NC 30 HH 10 Ng/L
Follow directions for data entry. In some cases a Par20 Aniline 10 Ng/L
comment menu list the available choices or a Par21 Chlorobenzene NC 140 FW 1 Ng/L
dropdown menu will provide a list you may select Par22 p-Cresol Ng/L
from. Error message occur if data entry does not
meet input criteria.
NCO090077 GENERIC RPA, input
7/26/2022

REASONABLE POTENTIAL ANALYSIS
1 Use"PASTE SPECIAL 2 Use"PASTE SPECIAL
Benzene Values"then"COPr• Toluene Values"then"COPY'
.Maximum data .Maximum data
points=58 points=58
Date Data BDL=1/2DL Results Date Data BDL=1/2DL Results
ICSB-2 2/10/2022 < 1 0.5 Std Dev. 0.00 ICSB-2 2/10/2022 < 1 0.5 Std Dev. 0.00
ICSB-3 2/10/2022 < 1 0.5 Mean 0.50 ICSB-3 2/10/2022 < 1 0.5 Mean 0.50
3 C.V.(default) 0.60 3 C.V.(default) 0.60
4 n 2 4 n 2
5 5
6 Mult Factor= 3.79 6 Mult Factor= 3.79
7 Max.Value 0.5 Ng/L 7 Max.Value 0.5 Ng/L
8 Max.Fred Cw 1.9 pg/L 8 Max.Fred Cw 1.9 Ng/L
9 9
10 10
11 11
12 12
13 13
14 14
15 15
16 16
17 17
18 18
19 19
20 20
21 21
22 22
23 23
24 24
25 25
26 26
27 27
28 28
29 29
30 30
31 31
32 32
33 33
34 34
35 35
36 36
37 37
38 38
39 39
40 40
41 41
42 42
43 43
44 44
45 45
46 46
47 47
48 48
49 49
50 50
51 51
52 52
53 53
54 54
55 55
56 56
57 57
58 58
NCO090077 GENERIC RPA,data
-2- 7/26/2022

REASONABLE POTENTIAL ANALYSIS
3 Use"PASTE SPECIAL 4 Use"PASTE SPECIAL
Ethylbenzene Values"then"COPY" Xylene Values then"COPY"
.Maximum data .Maximum data
points=58 points=58
Date Data BDL=1/2DL Results Date Data BDL=1/2DL Results
ICSB-2 2/10/2022 < 1 0.5 Std Dev. 0.00 ICSB-2 2/10/2022 < 1 0.5 Std Dev. 0.00
ICSB-3 2/10/2022 < 1 0.5 Mean 0.50 ICSB-3 2/10/2022 < 1 0.5 Mean 0.50
3 C.V.(default) 0.60 3 C.V.(default) 0.60
4 n 2 4 n 2
5 5
6 Mult Factor= 3.79 6 Mult Factor= 3.79
7 Max.Value 0.5 Ng/L 7 Max.Value 0.5 Ng/L
8 Max.Pred Cw 1.9 Ng/L 8 Max.Pred Cw 1.9 pg/L
9 9
10 10
11 11
12 12
13 13
14 14
15 15
16 16
17 17
18 18
19 19
20 20
21 21
22 22
23 23
24 24
25 25
26 26
27 27
28 28
29 29
30 30
31 31
32 32
33 33
34 34
35 35
36 36
37 37
38 38
39 39
40 40
41 41
42 42
43 43
44 44
45 45
46 46
47 47
48 48
49 49
50 50
51 51
52 52
53 53
54 54
55 55
56 56
57 57
58 58
NCO090077 GENERIC RPA,data
-3- 7/26/2022

REASONABLE POTENTIAL ANALYSIS
5 Use"PASTE 6
SPECIAL- Use"PASTE SPECIAL
MTBE Values"then Values"then"COPY'.
„COPY 1,2-Diohoroethane(1,2 DCA) Maximum data points
Maximum data =58
Date Data BDL=1/2DL Results points=58 Date Data BDL=1/2DL Results
ICSB-2 2/10/2022 < 1 2.5 Std Dev. 0.00 ICSB-2 2/10/2022 < 1 0.5 Std Dev. 0.00
ICSB-3 2/10/2022 < 1 2.5 Mean 2.50 ICSB-3 2/10/2022 < 1 0.5 Mean 0.50
3 C.V.(default, 0.60 3 C.V.(default) 0.60
4 n 2 4 n 2
5 5
6 Mult Factor= 3.79 6 Mult Factor= 3.79
7 Max.Value 2.5 Ng/L 7 Max.Value 0.5 Ng/L
8 Max.Pred 0 9.5 Ng/L 8 Max.Pred Cw 1.9 Ng/L
9 9
10 10
11 11
12 12
13 13
14 14
15 15
16 16
17 17
18 18
19 19
20 20
21 21
22 22
23 23
24 24
25 25
26 26
27 27
28 28
29 29
30 30
31 31
32 32
33 33
34 34
35 35
36 36
37 37
38 38
39 39
40 40
41 41
42 42
43 43
44 44
45 45
46 46
47 47
48 48
49 49
50 50
51 51
52 52
53 53
54 54
55 55
56 56
57 57
58 1 58
NCO090077 GENERIC RPA,data
-4- 7/26/2022

REASONABLE POTENTIAL ANALYSIS
se
7 SPECIAL- 8
Values"then Use"PASTE SPECIAL
Tetrachloroethylene(PERC) "Copr'. Napthalene Values"then"COPY".
Maximum Maximum data points
58 data points= -
Date Data BDL=1/2DL Results 58 Date Data BDL=1/2DL Results
ICSB-2 2/10/2022 < 1 0.5 Std Dev. 0.00 ICSB-2 2/10/2022 < 10 5 Std Dev. 0.00
ICSB-3 2/10/2022 < 1 0.5 Mean 0.50 ICSB-3 2/10/2022 < 10 5 Mean 5.00
3 C.V.(default) 0.60 3 C.V.(default) 0.60
4 n 2 4 n 2
5 5
6 Mult Factor= 3.79 6 Mult Factor= 3.79
7 Max.Value 0.5 Ng/L 7 Max.Value 5.0 Ng/L
8 Max.Pred Cw 1.9 Ng/L 8 Max.Pred Cw 19.0 pg/L
9 9
10 10
11 11
12 12
13 13
14 14
15 15
16 16
17 17
18 18
19 19
20 20
21 21
22 22
23 23
24 24
25 25
26 26
27 27
28 28
29 29
30 30
31 31
32 32
33 33
34 34
35 35
36 36
37 37
38 38
39 39
40 40
41 41
42 42
43 43
44 44
45 45
46 46
47 47
48 48
49 49
50 50
51 51
52 52
53 53
54 54
55 55
56 56
57 57
58 58
NCO090077 GENERIC RPA,data
-5- 7/26/2022

REASONABLE POTENTIAL ANALYSIS
9 Use"PASTE SPECIAL 10 Use"PASTE SPECIAL
alpha-Terpineol values then Copy. Benzoic Acids Values'then"COPY".
Maximum data points Maximum data points
=58 =58
Date Data BDL=1/2DL Results Date Data BDL=1/2DL Results
1 Std Dev. NO DATA ICSB-2 2/10/2022 < 50 25 Std Dev. 0.00
2 Mean NO DATA ICSB-3 2/10/2022 < 45.5 25 Mean 25.00
3 C.V. NO DATA 3 C.V.(default) 0.60
4 n 0 4 n 2
5 5
6 Mult Factor= N/A 6 Mult Factor= 3.79
7 Max.Value N/A Ng/L 7 Max.Value 25.0 Ng/L
8 Max.Pred Cw N/A pg/L 8 Max.Pred Cw 94.8 pg/L
9 9
10 10
11 11
12 12
13 13
14 14
15 15
16 16
17 17
18 18
19 19
20 20
21 21
22 22
23 23
24 24
25 25
26 26
27 27
28 28
29 29
30 30
31 31
32 32
33 33
34 34
35 35
36 36
37 37
38 38
39 39
40 40
41 41
42 42
43 43
44 44
45 45
46 46
47 47
48 48
49 49
50 50
51 51
52 52
53 53
54 54
55 55
56 56
57 57
58 58
NCO090077 GENERIC RPA,data
-6- 7/26/2022

REASONABLE POTENTIAL ANALYSIS
11 Use"PASTE SPECIAL 72 Us."PASTE SPECIAL
Pyridine Values"Maximum
he data
poM s' Polynuclear Aromatic Hydrocarbons(Pi vawee^then••cpoo Y"
Maximum data points Maximum data points
=58 =58
Date Data BDL=1/2DL Results Date Data BDL=1/2DL Results
1 Std Dev. NO DATA ICSB-2 2/10/2022 < 10 5 Std Dev. 0.32
2 Mean NO DATA ICSB-3 2/10/2022 < 9.1 4.55 Mean 4.78
3 C.V. NO DATA 3 C.V.(default) 0.60
4 n 0 4 n 2
5 5
6 Mult Factor= N/A 6 Mult Factor= 3.79
7 Max.Value N/A Ng/L 7 Max.Value 5.0 Ng/L
8 Max.Pred Cw N/A pg/L 8 Max.Pred Cw 19.0 pg/L
9 9
10 10
11 11
12 1k 12
13 13
14 14
15 15
16 16
0
17 17
18 18
19 19
20 20
21 21
22 22
23 23
24 24
25 25
26 26
27 27
28 28
29 29
30 30
31 31
32 32
33 33
34 34
35 35
36 36
37 37
38 38
39 39
40 40
41 41
42 42
43 43
44 44
45 45
46 46
47 47
48 48
49 49
50 50
51 51
52 52
53 53
54 54
55 55
56 56
57 57
58 1 58
NCO090077 GENERIC RPA,data
-7- 7/26/2022

REASONABLE POTENTIAL ANALYSIS
13 Use"PASTE SPECIAL 74 Use"PASTE SPECIAL
Acenaphthene Values"then"COPY". Anthracene Values"then"COPY".
Maximum data points Maximum data points
=58 =58
Date Data BDL=1/2DL Results Date Data BDL=1/2DL Results
ICSB-2 2/10/2022 < 10 5 Std Dev. 0.00 ICSB-2 2/10/2022 < 10 5 Std Dev. 0.00
ICSB-3 2/10/2022 < 9.1 5 Mean 5.00 ICSB-3 2/10/2022 < 9.1 5 Mean 5.00
3 C.V.(default) 0.60 3 C.V.(default) 0.60
4 n 2 4 n 2
5 5
6 Mult Factor= 3.7900 6 Mult Factor= 3.79
7 Max.Value 5.0 Ng/L 7 Max.Value 5.0 Ng/L
8 Max.Fred Cw 19.0 Ng/L 8 Max.Fred Cw 19.0 Ng/L
9 9
10 10
11 11
12 12
13 13
14 14
15 15
16 16
17 17
18 18
19 19
20 20
21 21
22 22
23 23
24 24
25 25
26 26
27 27
28 28
29 29
30 30
31 31
32 32
33 33
34 34
35 35
36 36
37 37
38 38
39 39
40 40
41 41
42 42
43 43
44 44
45 45
46 46
47 47
48 48
49 49
50 50
51 51
52 52
53 53
54 54
55 55
56 56
57 57
58 58
NCO090077 GENERIC RPA,data
-8- 7/26/2022

REASONABLE POTENTIAL ANALYSIS
15 Use"PASTE SPECIAL 76 Us.PASTE SPECIAL
Benzo(g,hij)perylene Values then"COPY". Fluoranthene Values"then"COPY".
Maximum data points Maximum data points
=58 =58
Date Data BDL=1/2DL Results Date Data BDL=1/2DL Results
ICSB-2 2/10/2022 < 10 5 Std Dev. 0.00 ICSB-2 2/10/2022 < 10 5 Std Dev. 0.00
ICSB-3 2/10/2022 < 9.1 5 Mean 5.00 ICSB-3 2/10/2022 < 9.1 5 Mean 5.00
3 C.V.(default) 0.60 3 C.V.(default) 0.60
4 n 2 4 n 2
5 5
6 Mult Factor= 3.79 6 Mult Factor= 3.79
7 Max.Value 5.0 Ng/L 7 Max.Value 5.0 Ng/L
8 Max.Fred Cw 19.0 Ng/L 8 Max.Fred Cw 19.0 pg/L
9 9
10 10
11 11
12 12
13 13
14 14 ALM
15 15
16 16
17 17
18 18
19 19
20 20
21 21
22 22
23 23
24 24
25 25
26 26
27 27
28 28
29 29
30 30
31 31
32 32
33 33
34 34
35 35
36 36
37 37
38 38
39 39
40 40
41 41
42 42
43 43
44 44
45 45
46 46
47 47
48 48
49 49
50 50
51 51
52 52
53 53
54 54
55 55
56 56
57 57
58 58
NCO090077 GENERIC RPA,data
-9- 7/26/2022

REASONABLE POTENTIAL ANALYSIS
17 Use"PASTE SPECIAL 18 Use"PASTE SPECIAL
Fluorene Values"then"COPr• Phenanthrene Values"then"COPY'
.Maximum data .Maximum data
points=58 points=58
Date Data BDL=1/2DL Results Date Data BDL=1/2DL Results
ICSB-2 2/10/2022 < 10 6 Std Dev. 0.00 ICSB-2 2/10/2022 < 10 5 Std Dev. 0.00
ICSB-3 2/10/2022 < 9.1 6 Mean 6.00 CS13-3 2/10/2022 < 9.1 5 Mean 5.00
3 C.V.(default) 0.60 3 C.V.(default) 0.60
4 n 2 4 n 2
5 5
6 Mult Factor= 3.79 6 Mult Factor= 3.79
7 Max.Value 6.0 Ng/L 7 Max.Value 5.0 Ng/L
8 Max.Fred Cw 22.7 pg/L 8 Max.Fred Cw 19.0 pg/L
9 9
10 10
11 11
12 12
13 13
14 14
15 15
16 16
17 17
18 18
19 19
20 20
21 21
22 22
23 23
24 24
25 25
26 26
27 27
28 28
29 29
30 30
31 31
32 32
33 33
34 34
35 35
36 36
37 37
38 38
39 39
40 40
41 41
42 42
43 43
44 44
45 45
46 46
47 47
48 48
49 49
50 50
51 51
52 52
53 53
54 54
55 55
56 56
57 57
58 58
NCO090077 GENERIC RPA,data
-10- 7/26/2022

REASONABLE POTENTIAL ANALYSIS
19
Use"PASTE SPECIAL
Pyrene Values"then"COPY"
.Maximum data
points=58
Date Data BDL=1/2DL Results
ICSB-2 2/10/2022 < 10 5 Std Dev. 0.00
ICSB-3 2/10/2022 < 9.1 5 Mean 5.00
3 C.V.(default) 0.60
4 n 2
5
6 Mult Factor= 3.79
7 Max.Value 5.0 Ng/L
8 Max.Pred Cw 19.0 Ng/L
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
NCO090077 GENERIC RPA,data
11- 7/26/2022

Irwin Creek Tributary to Remount Road Project REASONABLE POTENTIAL ANALYSIS Outfall 001
NCO090077 2018 Generic RPA-95%Probability/95%Confidence Qw=0.144 MGD
MAXIMUM DATA POINTS=58
Qw(MOD)= 0.1440 WWTP/WTP Class:PC-1
1Q10S(cfs)= 0.00 IWC%@ 1Q10S= 100
7QIOS lets)= 0.00 IWC% @ 7Q10S= 100
7Q10W(cfs)= 0.00 IW%C @ 7Q10W= 100
30Q2(cfs)= 0.00 IWC%@ 30Q2= 100
Avg.Stream Flow,QA(cfs)= 0.00 IWC%@ QA= 100
Receiving Stream:UT to Irwin Creek HUC 30501030101 Stream Class:C
PARAMETER NC STANDARDS OR EPA CRITERIA rn REASONABLE POTENTIAL RESULTS RECOMMENDED ACTION
r
TYPEApplied Chronic Standard Acutc a n #Det. Max Pred Cw Allowable Cw
Acute: NO WQS
Benzene C 51 HH(Qavg) 1 µg/L 2 0 1.9 _ _ _____ _ __ _ _ _ _ -------------------
Limited
Note:n<9 Default C.V. Chronic: 51.00 Limited Data(new Permit,New Waste Stream)-
data set NO DETECTS Max MDL=1 apply Monthly Monitoring wth limit,Pollutant of
concern
Acute: NO WQS
Toluene NC 11 FW(7Q10s) I µg/L 2 0 1.9
Note:n<9 Default C.V. Chronic: 11.06 Limited Data(new Permit,New Waste Stream)-
Limited data set NO DETECTS Max MDL=1 apply Monthly Monitoring wth limit,Pollutant of
concern
Acute: NO WQS
Ethylbenzene NC 97 FW(7Q10s) 1 µg/L 2 0 1lt _ _ _____ _ __ ----------------------------
Limited
Note:n<9 Default C.V. Chronic: 97.00 Limited Data(new Permit,New Waste Stream)-
apply Monthly Monitoring wth limit,Pollutant of
data set NO DETECTS Max MDL=1 concern
Acute: NO WQS
Xylene NC 670 FW(7Q10s) 1 µg/L 2 0 1.9
Note:n<9 Default C.V. Chronic: 670.00 Limited Data(new Permit,New Waste Stream)-
Limited data set NO DETECTS Max MDL=1 apply Monthly Monitoring wth limit,Pollutant of
concern
Acute: NO WQS
MTBE C 1500 HH(Qavg) 5 µg/L 2 0 9.5 _ _ __ _ __ _ _ _ _ _ _ _ _ _ _ _ _ __
Note:n<9 Default C.V. Chronic: 1,500.00 Limited Data(new Permit,New Waste Stream)-
Limited data set NO DETECTS Max MDL=5 apply Monthly Monitoring wth limit,Pollutant of
concern
Acute: NO WQS
1,2-Dichoroelhane(1,2 DCA) C 650 HH(Qavg) 1 µg/L 2 0 1.9
-- -----------------------------
Note:n<9 Default C.V. Chronic: 650.00 Limited Data(new Permit,New Waste Stream)-
Limited data set NO DETECTS Max MDL=1 apply Monthly Monitoring wth limit,Pollutant of
concern
Acute: NO WQS
Tetrachloroethylene(PERC) C 3.3 HH(Qavg) 1 µg/L 2 0 1.9 _ _ ____ _---------------------------------
Limited
Note:n<9 Default C.V. Chronic: 3.30 Limited Data(new Permit,New Waste Stream)-
data set NO DETECTS Max MDL=1 apply Monthly Monitoring wth limit,Pollutant of
concern
Acute: NO WQS
Napthalene NC 12 FW(7Q10s) 2 µg/L 2 0 19.0
Note:n<9 Default C.V. Chronic: 12.00 Limited Data(new Permit,New Waste Stream)-
apply Monthly Monitoring wth limit,Pollutant of
Limited data set NO DETECTS Max MDL=10 concern
Acute: NO WQS
alpha-Terpineol µg/L 0 0 N/A _ _ __________ _ _ _ _ _ _ _ _ _ _ _ a_ __
Chronic: No Data(new Permit,New Waste Stream)- pply
Monthly Monitoring,Pollutant of concern
Acute: NO WQS
Benzoic Acids NC 9000 FW(7Q10s) 50 µgfL 2 0 94.8 _ _ __ _
Note:n<9 Default C.V. Chronic: 9,000.00 Limited Data(new Permit,New Waste Stream)-
Limited data set NO DETECTS Max MDL=50 apply Monthly Monitoring wth limit,Pollutant of
concern
NCO090077 GENERIC RPA,rpa
Page 12 of 13 7/26/2022

Irwin Creek Tributary to Remount Road Project REASONABLE POTENTIAL ANALYSIS Outfall 001
NCO090077 2018 Generic RPA-95%Probability/95%Confidence Qw=0.144 MGD
Acute: NO WQS
Pyridine NC 1300 HH(7Q10s) ug/L 0 0 N;A
Chronic: 1,300.00 No Data(new Permit,New Waste Stream)-apply
Monthly Monitoring,Pollutant of concern
Acute: NO WQS
_Polynuclear Aromatic Hydrocarbons(PAH) C 0.0311 HH(Qavg) ue,l. 2 0 19.0 _ ____ _ __ _ _ _ _ _ _ _ _ _ _ _ _ _
Note:n<9 Default C.V. Chronic: 0.03 Limited Data(new Permit,New Waste Stream)-
Limited data set .VO DETECTS Max MDL=10 apply Monthly Monitoring wth limit,Pollutant of
concern
Acute: NO WQS
Acenaphthene NC 60 FW(7Q10s) 10 µg/L 2 0 19.0
Note:n<9 Default C.V. Chronic: 66.06 Limited Data(new Permit,New Waste Stream)-
Limited data set NO DETECTS Max MDL=10 apply Monthly Monitoring wth limit,Pollutant of
concern
Acute: NO WQS
Anthracene NC 0.05 FW(7Q10s) 10 µg/L 2 0 19.0 _ _ ____ _ _ _ _ _ _ _ _ _ _ _ _ _ __
Note:n<9 Default C.V. Chronic: 0.05 Limited Data(new Permit,New Waste Stream)-
Limited data set NO DETECTS Max MDL=10 apply Monthly Monitoring wth limit,Pollutant of
concern
Acute: NO WQS
Benzo(g,h,i)perylene 10 ug/L 2 0 19.0
Vote:n<9 Default C.V. Chronic:
Limited data set NO DETECTS Max MDL=10
Acute: NO WQS
Fluoranthene NC 0.11 FW(7Q10s) 10 µg/L 2 0 19.0 _ _ ____ ____ _ _ _ _ _ _ _ _ _ _ _ _ __
Note:a<9 Default C.V. Chronic: 0.11 Limited Data(new Permit,New Waste Stream)-
Limited data set NO DETECTS Max MDL=10 apply Monthly Monitoring wth limit,Pollutant of
concern
Acute: NO WQS
Fluorene NC 30 FW(7Q10s) 12 µg/L 2 0 22.7
Note:n<9 Default C.V. Chronic: 36.06 Limited Data(new Permit,New Waste Stream)-
Limited data set NO DETECTS Max MDL=12 apply Monthly Monitoring wth limit,Pollutant of
concern
Acute: NO WQS
Phenanthrene NC 0.7 FW(7Q10s) 10 µg/L 2 0 19.0 _ _ _
Note:n<9 Default C.V. Chronic: 0.70 Limited Data(new Permit,New Waste Stream)-
Limited data set NO DETECTS Max MDL=10 apply Monthly Monitoring wth limit,Pollutant of
concern
Acute: NO WQS
Pyrene NC 30 1U1(7Q10s) 10 µg/L 2 0 19.0
Note:n<9 Default C.V. Chronic: 36.06 Limited Data(new Permit,New Waste Stream)-
apply Monthly Monitoring wth limit,Pollutant of
Limited data set NO DETECTS Max MDL=0 concern
Acute: NO WQS
Aniline 10 ue/L 0 0 N/A ----------------------------------------
No Data(new Permit,New Waste Stream)-apply
Monthly Monitoring,Pollutant of concern
Acute: NO WQS
Chlorobenzene NC 140 FW(7Q10s) 1 µg/L 0 0 N/A
Chronic: 140.0000 Limited Data(new Permit,New Waste Stream)-
apply Monthly Monitoring wth limit,Pollutant of
concern
Acute: NO WQS
p-Cresol ue/I. 0 0 N/A _ _ __________ _ _ _ _ _ _ _ _ _ _ _ _ __
Chronic: No Data(new Permit,New Waste Stream)-apply
Monthly Monitoring,Pollutant of concern
NCO090077 GENERIC RPA,rpa
Page 13 of 13 7/26/2022

Freshwater RPA - 95% Probability/95% Confidence Using Metal Translators
MAXIMUM DATA POINTS = 58
REQUIRED DATA ENTRY NEED ADDITIONAL DATA INPUTS
Table 1. Project Information Table 2. Parameters of Concern
❑CHECK IF HQW OR ORW WQS Name WQS Type Chronic Modifier Acute PQL Units
Facility Name Irwin Creek Tributary to Remount Road Project Par01 Arsenic Aquactic Life C 150 FW 340 ug/L
WWTP/WTP Class PC-1 Par02 Arsenic Human Health C 10 HH/WS N/A ug/L
Water Supply
NPDES Permit NCO090077 Par03 Beryllium Aquatic Life NC 6.5 FW 65 ug/L
Outfall 001 Par04 Cadmium Aquatic Life NC 0.5899 FW 3.2396 ug/L
Flow,Qw(MGD) 0.144 Par05 Chlorides Aquatic Life NC 230 FW mg/.
Receiving Stream UT to Irwin Creek ParO Chlorinated Phenolic Compounds Water Supply NC 1 A ug/L
HUC Number 030501030101 Par07 Total Phenolic Compounds Aquatic Life NC 300 A ug/L
Stream Class C Par08 Chromium III Aquatic Life NC 117.7325 FW 905.0818 ug/L
❑Apply WS Hardness WQC Par09 Chromium VI Aquatic Life NC 11 FW 16 pg/L
7Q10s(cfs) 0.00 Par10 Chromium,Total Aquatic Life NC N/A FW N/A pg/L
7Q10w(cfs) 0.00 Par11 Copper Aquatic Life NC 7.8806 FW 10.4720 ug/L
30Q2(cfs) 0.00 Par12 Cyanide Aquatic Life NC 5 FW 22 10 ug/L
CIA(cfs) 0.00 Part Fluoride Aquatic Life NC 1,800 FW ug/L
1010s(cfs) 0.00 Part Lead Aquatic Life NC 2.9416 FW 75.4871 ug/L
Effluent Hardness 25 mg/L(Avg) Parts Mercury Aquatic Life NC 12 FW 0.5 ng/L
Upstream Hardness 25 mg/L(Avg) I Part Molybdenum Human Health NC 2000 HH ug/L
Combined Hardness Chronic 25 mg/L I Part Nickel Aquatic Life NC 37.2313 1 FW 335.2087 pg/L
Combined Hardness Acute 25 m /L I Par18 Nickel Water Supply NC 25.0000 WS N/A pg/L
-------------------
Data Source(s) Par19 Selenium Aquatic Life NC 5 FW 56 ug/L
❑CHECK TO APPLY MODEL Par20 Silver Aquatic Life NC 0.06 FW 0.2964 ug/L
Par21 Zinc Aquatic Life NC 126.7335 FW 125.7052 ug/L
Par22 Nitrate/Nitrite as N mg/L
Par23 Barium Aquatic Life NC 21000 FW pg/L
Par24 Bromide mg/L
Follow directions for data entry.In some cases a Par25 Sulfate mg/L
comment menu list the available choices or a
dropdown menu will provide a list you may select
from.Error message occur if data entry does not
meet input criteria.
NCO090077 FW RPA,input
7/27/2022

REASONABLE POTENTIAL ANALYSIS
H1 Use"PASTE SPECIAL H2 Use"PASTE SPECIAL
Effluent Hardness values"then"COPY". Upstream Hardness Values"then"COPY".
Maximum data points Maximum data points
=58 =58
Date Data BDL=1/2DL Results Date Data BDL=1/2DL Results
1 25 25 Std Dev. N/A 1 25 25 Std Dev. N/A
2 Mean 25.0000 2 Mean 25.0000
3 C.V. 0.0000 3 C.V. 0.0000
4 n 1 4 n 1
5 10th Per value 25.00 mg/L 5 10th Per value 25.00 mg/L
6 Average Value 25.00 mg/L 6 Average Value 25.00 mg/L
7 Max.Value 25.00 mg/L 7 Max.Value 25.00 mg/L
8 8
9 9
10 10
11 11
12 12
13 13
14 14
15 15
16 16
17 17
18 18
19 19
20 20
21 21
22 22
23 23
24 24
25 25
26 26
27 27
28 28
29 29
30 30
31 31
32 32
33 33
34 34
35 35
36 36
37 37
38 38
39 39
40 40
41 41
42 42
43 43
44 44
45 45
46 46
47 47
48 48
49 49
50 50
51 51
52 52
53 53
54 54
55 55
56 56
57 57
58 1 58
NCO090077 FW RPA,data
-2- 7/27/2022

REASONABLE POTENTIAL ANALYSIS
Par01&Par02 Par04
Use"PASTE SPECIAL Use"PASTE SPECIAL
Values"then"COPY". Values"then"COPY".
Arsenic Maximum data points Cadmium Maximum data points
—58 =58
Date Data BDL=1/2DL Results Date Data BDL=1/2DL Results
ICSB-2 2/10/2022 < 10 5 Std Dev. 0.0000 ICSB-2 2/10/2022 < 1 0.5 Std Dev. 0.0000
ICSB-3 2/10/2022 < 10 5 Mean 5.0000 ICSB-3 2/10/2022 < 1 0.5 Mean 0.5000
3 C.V. 0.0000 3 C.V. 0.0000
4 n 2 4 n 2
5 5
6 Mult Factor= 1.00 6 Mult Factor= 1.00
7 Max.Value 5.0 ug/L 7 Max.Value 0.500 ug/L
8 Max.Pred Cw O DETECTS ug/L 8 Max.Pred Cw O DETECTS ug/L
9 9
10 10
11 11
12 12
13 13
14 14
15 15
16 16
17 17
18 18
19 19
20 20
21 21
22 22
23 23
24 24
25 25
26 26
27 27
28 28
29 29
30 3
31 31
32 32
33 33
34 34
35 35
36 36
37 37
38 38
39 39�
40 40
41 41
42 42
43 43
44 44
45 45
46 46
47 47
48 48
49 49
50 50
51 51
52 52
53 53
54 54
55 55
56 56
57 57
58 1 58
NCO090077 FW RPA,data
-3- 7/27/2022

REASONABLE POTENTIAL ANALYSIS
Par05 Par06
Use"PASTE SPECIAL- Use"PASTE SPECIAL
Chlorides Values then"COPY". Chlorinated Phenolic Compounds Values"then"COPY".
Maximum data points=58 Maximum data points
=58
Date Data BDL=1/2DL Results Date Data BDL=1/2DL Results
ICSB-2 2/10/2022 39.6 39.6 Std Dev. 19.2333 ICSB-2 2/10/2022 < 10 5 Std Dev. 0.3182
ICSB-3 2/10/2022 12.4 12.4 Mean 26.0 ICSB-3 2/10/2022 < 9.1 4.55 Mean 4.7750
3 C.V.(default) 0.6000 3 C.V.(default) 0.6000
4 n 2 4 n 2
5 5
6 Mult Factor= 3.8 6 Mult Factor= 3.79
7 Max.Value 39.6 mg/L 7 Max.Value 5.0 ug/L
8 Max.Pred Cw 150.1 mg/L 8 Max.Pred Cw O DETECTS ug/L
9 9
10 10
11 11
12 12
13 13
14 14
15 15
16 16
17 17
18 18
19 19
20 20
21 21
22 22
23 23
24 24
25 25
26 26
27 27
28 28
29 29
30 30
31 31
32 32
33 33
34 34
35 35
36 36
37 37
38 38
39 39
40 40
41 41
42 42
43 43
44 44
45 45
46 46
47 47
48 48
49 49
50 50
51 51
52 52
53 53
54 54
55 55
56 56
57 57
58 1 58
NCO090077 FW RPA,data
-4- 7/27/2022

REASONABLE POTENTIAL ANALYSIS
Par07 Use"PASTE SPECIAL Par08 Use"PASTE SPECIAL
Total Phenolic Compounds Values"then"COPr'. Chromium III Values"then"COPr'.
Maximum data points Maximum data points
=58 =58
Date Data BDL=1/2DL Results Date Data BDL=1/2DL Results
ICSB-2 2/10/2022 < 10 5 Std Dev. 0.3182 ICSB-2 2/10/2022 Std Dev. NO DATA
ICSB-3 2/10/2022 < 9.1 4.55 Mean 4.7750 ICSB-3 2/10/2022 Mean NO DATA
3 C.V.(default) 0.6000 3 C.V. NO DATA
4 n 2 4 n 0
5 5
6 Mult Factor= 3.79 6 Mult Factor= N/A
7 Max.Value 5.0 ug/L 7 Max.Value N/A Ng/L
8 Max.Pred Cw O DETECTS ug/L 8 Max.Pred Cw N/A pg/L
9 9
10 10
11 11
12 12
13 13
14 14
15 15
16 16
17 17
18 18
19 19
20 20
21 21
22 22
23 23
24 24
25 25
26 26
27 27
28 28
29 29
30 30
31 31
32 32
33 33
34 34
35 35
36 36
37 37
38 38
39 39
40 40
41 41
42 42
43 43
44 44
45 45
46 46
47 47
48 48
49 49
50 50
51 51
52 52
53 53
54 54
55 55
56 56
57 57
58 58
NCO090077 FW RPA,data
-5- 7/27/2022

REASONABLE POTENTIAL ANALYSIS
Par09 Use"PASTE SPECIAL Par10 Use"PASTE SPECIAL
Values"then"COPY". Values"then"COPY'.
Chromium VI Maximum data points Chromium,Total Maximum data points
=58 =58
Date Data BDL=1/2DL Results Date Data BDL=1/2DL Results
ICSB-2 2/10/2022 < 0.1 0.05 Std Dev. 0.0000 ICSB-2 2/10/2022 32.6 32.6 Std Dev. 21.2839
ICSB-3 2/10/2022 < 0.1 0.05 Mean 0.0500 ICSB-3 2/10/2022 < 5 2.5 Mean 17.5500
3 C.V. 0.0000 3 C.V.(default) 0.6000
4 n 2 4 n 2
5 5
6 Mult Factor= 1.00 6 Mult Factor= 3.79
7 Max.Value 0.1 Ng/L 7 Max.Value 32.6 Ng/L
8 Max.Pred Cw O DETECTS Ng/L 8 Max.Pred Cw 123.6 pg/L
9 9
10 10
11 11
12 12
13 13
14 14
15 15
16 16
17 17
18 18
19 19
20 20�
21 21
22 22
23 23
24 24
25 25
26 26
27 27
28 28
29 29
30 30
31 31
32 32
33 33
34 34
35 35
36 36
37 37
38 38
39 39
40 40
41 41
42 42
43 43
44 44
45 45
46 46
47 47
48 48
49 49
50 50
51 51
52 52
53 53
54 54
55 55
56 56
57 57
58 58
NCO090077 FW RPA,data
-6- 7/27/2022

REASONABLE POTENTIAL ANALYSIS
Pall Use"PASTE SPECIAL Par12 Use"PASTE SPECIAL
CO er Values"then Cyanide Values"then"COPr•.
pp Maximum data points y Maximum data points
=58 =58
Date Data BDL=1/2DL Results Date Data BDL=1/2DL Results
ICSB-2 2/10/2022 Std Dev. NO DATA ICSB-2 2/10/2022 < 8 5 Std Dev. 109.6016
ICSB-3 2/10/2022 Mean NO DATA ICSB-3 2/10/2022 160 160 Mean 82.50
3 C.V. NO DATA 3 C.V.(default) 0.6000
4 n 0 4 n 2
5 5
6 Mult Factor= N/A 6 Mult Factor= 3.79
7 Max.Value N/A ug/L 7 Max.Value 160.0 ug/L
8 Max.Pred Cw N/A ug/L 8 Max.Pred Cw 606.4 ug/L
9 9
10 10
11 11
12 12
13 13
14 14
15 15
16 16
17 17
18 18
19 19
20 20
21 21
22 22
23 23
24 24
25 25
26 26
27 27
28 28
29 29
30 30
31 31
32 32
33 33
34 34
35 35
36 36
37 37
38 38
39 39
40 40
41 41
42 42
43 43
44 44
45 45
46 46
47 47
48 48
49 49
50 50
51 51
52 52
53 53
54 54
55 55
56 56
57 57
58 58
NCO090077 FW RPA,data
-7- 7/27/2022

REASONABLE POTENTIAL ANALYSIS
Par13 Use"PASTE SPECIAL Par14 Use"PASTE SPECIAL
Values"then"COPY". Values"then"COPY".
Fluoride Maximum data points Lead Maximum data points
=58 =58
Date Data BDL=1/2DL Results Date BDL=1/2DL Results
ICSB-2 2/10/2022 < 100 50 Std Dev. 219.2031 ICS13-2 2/10/2022 13.8 13.8 Std Dev. 6.1518
ICSB-3 2/10/2022 360 360 Mean 205.0000 ICS13-3 2/10/2022 5.1 5.1 Mean 9.4500
3 C.V.(default) 0.6000 3 C.V.(default) 0.6000
4 n 2 4 n 2
5 5
6 Mult Factor= 3.79 6 Mult Factor= 3.79
7 Max.Value 360.0 ug/L 7 Max.Value 13.800 ug/L
8 Max.Pred Cw 1364.4 ug/L 8 Max.Pred Cw 52.302 ug/L
9 9
10 10
11 11
12 12
13 13
14 14
15 15
16 16
17 17
18 18
19 19
20 20�
21 21
22 22
23 23
24 24
25 25
26 26
27 27
28 28
29 29
30 30
31 31
32 32
33 33
34 34
35 35
36 36
37 37
38 38
39 39
40 40
41 41
42 42
43 43
44 44
45 45
46 46
47 47
48 48
49 49
50 50
51 51
52 52
53 53
54 54
55 55
56 56
57 57
58 58
NCO090077 FW RPA,data
-8- 7/27/2022

REASONABLE POTENTIAL ANALYSIS
Par15 Paf19
Use"PASTE SPECIAL Use"PASTE SPECIAL
Mercury Values"then"COPY". Selenium Values"then"COPY".
Maximum data points Maximum data points
=58 =58
Date Data BDL=1/2DL Results Date Data BDL=1/2DL Results
ICSB-2 2/10/2022 < 200 100 Std Dev. 0.0000 ICSB-2 2/10/2022 < 10 5 Std Dev. 0.0000
ICSB-3 2/10/2022 < 200 100 Mean 100.0000 ICSB-3 2/10/2022 < 10 5 Mean 5.0000
3 C.V. 0.0000 3 C.V. 0.0000
4 n 2 4 n 2
5 5
6 Mult Factor= 1.00 6 Mult Factor= 1.00
7 Max.Value 100.0 ng/L 7 Max.Value 5.0 ug/L
8 Max.Pred Cw O DETECTS ng/L 8 Max.Pred Cw O DETECTS ug/L
9 9
10 10
11 11
12 12
13 13
14 14
15 15
16 16
17 17
18 18
19 19
20M 20
21 21
22 22
23 23
24 24
25 25
26 26
27 27
28 28
29 29
30 30
31 31
32 32
33 33
34 34
35 35
36 36
37 37
38 38
39 39
40 40
41 41
42 42
43 43
44 44
45 45
46 46
47 47
48 48
49 49
50 50
51 51
52 52
53 53
54 54
55 55
56 56
57 57
58 58
NCO090077 FW RPA,data
-9- 7/27/2022

REASONABLE POTENTIAL ANALYSIS
Par20 Use"PASTE SPECIAL Par21 Use"PASTE SPECIAL
Silver Values"then"COPY". Zinc Values"then"COPY".
Maximum data points Maximum data points
=58 =58
Date Data BDL=1/2DL Results Date Data BDL=1/2DL Results
ICSB-2 2/10/2022 < 5 2.5 Std Dev. 0.0000 ICSB-2 2/10/2022 Std Dev. NO DATA
ICSB-3 2/10/2022 < 5 2.5 Mean 2.5000 ICSB-3 2/10/2022 Mean NO DATA
3 C.V. 0.0000 3 C.V. NO DATA
4 n 2 4 n 0
5 5
6 Mult Factor= 1.00 6 Mult Factor= N/A
7 Max.Value 2.500 ug/L 7 Max.Value N/A ug/L
8 Max.Pred Cw O DETECTS ug/L 8 Max.Pred Cw N/A ug/L
9 9
10 10
11 11
12 12
13 13
14 14
15 15
16M 16
17 17
18 18
19 19
20 20
21 21
22 22
23 23
24 24
25 25
26 26
27M 27
28 28
29 29
30 30
31 31
32 32
33 33
34 34
35 35
36 36
37 37
38 38
39 39
40 40
41 41
42 42
43 43
44 44
45 45
46 46
47 47
48 48
49 49
50 50
51 51
52 52
53 53
54 54
55 55
56 56
57 57
58 1 58
NCO090077 FW RPA,data
-10- 7/27/2022

REASONABLE POTENTIAL ANALYSIS
Par22 Use"PASTE SPECIAL Par23 Use"PASTE SPECIAL
Nitrate/Nitrite as N Values"then"COPY". Barium Values"then"COPY".
Maximum data points Maximum data points
=58 =58
Date Data BDL=1/2DL Results Date Data BDL=1/2DL Results
1 2/10/2022 9.3 9.3 Std Dev. 6.5054 ICS13-2 2/10/2022 77.8 77.8 Std Dev. 376.3222
2 2/10/2022 < 0.2 0.1 Mean 4.7000 ICS13-3 2/10/2022 610 610 Mean 343.9000
3 C.V.(default) 0.6000 3 C.V.(default) 0.6000
4 n 2 4 n 2
5 5
6 Mult Factor= 3.79 6 Mult Factor= 3.79
7 Max.Value 9.3000 mg/L 7 Max.Value 610.0000 Ng/L
8 Max.Pred Cw 35.2470 mg/L 8 Max.Pred Cw 2311.9000 Ng/L
9 9
10 10
11 11
12 12
13 13
14 14
15 15
16 16
17 17
18 18
19 19
20 20�
21 21
22 22
23 23
24 24
25 25
26 26
27 27
28 28
29 29
30 30
31 31
32 32
33 33
34 34
35 35
36 36
37 37
38 38
39 39
40 40
41 41
42 42
43 43
44 44
45 45
46 46
47 47
48 48
49 49
50 50
51 51
52 52
53 53
54 54
55 55
56 56
57 57
58 1 58
NCO090077 FW RPA,data
11- 7/27/2022

REASONABLE POTENTIAL ANALYSIS
Par24 Use"PASTE SPECIAL Par25 Use"PASTE SPECIAL
Bromide Values"then"COPY". Sulfate Values"then"COPY".
Maximum data points Maximum data points
58 =58
Date Data BDL=1/2DL Results Date Data BDL=1/2DL Results
ICSB-2 2/10/2022 0.19 0.19 Std Dev. 0.1061 ICS13-2 2/10/2022 454 454 Std Dev. 319.4708
ICSB-3 2/10/2022 0.34 0.34 Mean 0.2650 ICS13-3 2/10/2022 2.2 2.2 Mean 228.1000
3 C.V.(default) 0.6000 3 C.V.(default) 0.60
4 n 2 4 n 2
5 5
6 Mult Factor= 3.79 6 Mult Factor= 3.79
7 Max.Value 0.3400 mg/L 7 Max.Value 454.0000 mg/L
8 Max.Pred Cw 1.2886 mg/L 8 Max.Pred Cw 1720.6600 mg/L
9 9
10 10
11 11
12 12
13 13
14 14
15 15
16 16
17 17
18 18
19 19
20 20
21 21
22 22
23 23
24 24
25 25
26 26
27 27
28 28
29 29
30 30
31 31
32 32
33 33
34 34
35 35
36 36
37 37
38 38
39 39
40 40
41 41
42 42
43 43
44 44
45 45
46 46
47 47
48 48
49 49
50 50
51 51
52 52
53 53
54 54
55 55
56 56
57 57
58 1 58
NCO090077 FW RPA,data
-12- 7/27/2022

Irwin Creek Tributary to Remount Road Project Outfall 001
NCO090077 Freshwater RPA- 95% Probability/95% Confidence Using Metal Translators Qw = 0.144 MGD
MAXIMUM DATA POINTS = 58
Qw(MGD)= 0.14 WWTP/WTP Class: PC-1 COMBINED HARDNESS(me/L)
1Q10S(cfs)= 0.00 lWC% @ 1Q10S = 100 Acute=25 mg/L
7Q10S(cfs)= 0.00 IWC% @ 7Q10S= 100 Chronic=25 mg/L
7QIOW(cfs)= 0.00 IWC%@ 7QIOW= 100
30Q2(cfs)= 0.00 1WC%@ 30Q2= 100
Avg.Stream Flow,QA(cfs)= 0.00 IW%C @ QA= 100
Receiving Stream: UT to Irwin Creek HUC 030501030101 Stream Class: C
PARAMETER NC STANDARDS OR EPA CRITERIA y REASONABLE POTENTIAL RESULTS RECOMMENDED ACTION
TYPE <Applied7 �
(t) Chronic Standard Acute a M D #Det. Max Pred Cw Allowable Cw
Acute(FW): 340.0 Limited Data(new Permit,New Waste Stream)-
Arsenic C 150 FW 340 ug/L apply Monthly Monitoring wth limit,Pollutant of
g concern
------------------ ---------------------------
2 0 NO DETECTS Chronic(FW): 150.0 Limited Data(new Permit,New Waste Stream)-
apply Monthly Monitoring wth limit,Pollutant of
Max MDL=10 concern
Arsenic C 10 HII/WS ug/L Note:n 5 9 Chronic(HH): 10.0 Limited Data(new Permit,New Waste Stream)-
apply Monthly Monitoring wth limit,Pollutant of
Limited data set Max MDL=10 concern
Acute: 65.00 No Data(new Permit,New Waste Stream)-apply
Beryllium NC 6.5 FW 65 ug/L 0 0 N/A Monthly Monitoring with Limit,Pollutant of concern
------------- ---------------------------
Chronic: 6.50 No Data(new Permit,New Waste Stream)-apply
Monthly Monitoring with Limit,Pollutant of concern
Acute: 3.240 Limited Data(new Permit,New Waste Stream)-
C apply Monthly Monitoring wth limit,Pollutant of
Cadmium NC 0.5899 FW 3.2396 ug/L 2 0 NO DETECTS concern
----------------------------------------------
Note:n 5 9 Chronic: 0.590 Limited Data(new Permit,New Waste Stream)-
Limited data set Max MDL=1 apply Monthly Monitoring wth limit,Pollutant of
concern
Acute: NO WQS Limited Data(new Permit,New Waste Stream)-
Chlorides NC 230 FW mg/L 2 2 150.1 apply Monthly Monitoring wth limit,Pollutant of
g concern
Note:n<9 Default C.V. Chronic: 230.0 Limited Data(new Permit,New Waste Stream)-
Limited data set No value>Allowable Cw apply Monthly Monitoring wth limit,Pollutant of
concern
Acute: NO WQS No detects,limited data set,monitor monthly with EPA
Chlorinated Phenolic Compounds NC 1 A ug/L 2 0 NO DETECTS Method 625.1.
-----------------------------------------
Note:n 5 9 Chronic: 1.0 No detects,limited data set,monitor monthly with EPA
Limited data set Max MDL=10 Method 625.1.
Acute: NO WQS Limited Data(new Permit,New Waste Stream)-
Total Phenolic Compounds NC 300 A ug/L 2 0 NO DETECTS apply Monthly Monitoring wth limit,Pollutant of
concern
------- ----------------------------
Note:n<_9 Chronic: 300.0 Limited Data(new Permit,New Waste Stream)-
apply Monthly Monitoring wth limit,Pollutant of
Limited data set Max MDL=10 concern
NCO090077 FW RPA,rpa
Page 13 of 16 7/27/2022

Irwin Creek Tributary to Remount Road Project - Outfall 001
NCO090077 Freshwater RPA- 95% Probability/95% Confidence Using Metal Translators Qw = 0.144 MGD
Acute: 905.1 No Data(new Permit,New Waste Stream)-apply
Chromium III NC 117.7325 FW 905.0818 µg/L 0 0 N/A Monthly Monitoring with Limit,Pollutant of concern
- ---------------------------
Chronic: 117.7 No Data(new Permit,New Waste Stream)-apply
Monthly Monitoring with Limit,Pollutant of concern
Acute: 16.0 apply Monthly Monitoring wth limit,Pollutant of
Chromium VI NC 11 FW 16 µg/L 2 0 NO DETECTS _ _ _
Note:n<9 Chronic: 11.0 E'mmiilee?Da 6(rTeW-Fl�F-mit,-Mew WTs'te Str6arli.:—
Limited data set Max MDL=0.1 apply Monthly Monitoring wth limit,Pollutant of
Tot Cr value(s)<50 and<Cr VI Allowable Cw
Chromium,Total NC µg/L 2 1 I 123.6 Max reported value=32.6 c:Monitor Total Chromium and Chromium along
with a limit for Chromium VI if any Total Chromium
Note:n<9 Default C.V. sample is >the Chromium VI Allowable Cw but<the
Limited data set Chromium III Allowable Cw.
Acute: 10.47 No Data(new Permit,New Waste Stream)-apply
Copper NC 7.8806 FW 10.4720 ug/L 0 0 N/A Monthly Monitoring with Limit,Pollutant of concern
------------------ ---------------------------
Chronic: 7.88 No Data(new Permit,New Waste Stream)-apply
Monthly Monitoring with Limit,Pollutant of concern
Acute: 22.0 RP for Limited Dataset(n<8 samples)-apply Monthly
Cyanide NC 5 FW 22 10 ug/L 2 1 606.4 Monitoring with Limit,Pollutant of concern
Note:n<9 Default C.V. Chronic: 5.0 RP for Limited Dataset(n<8 samples)-apply Monthly
Limited data set 1 value(s)>Allowable Cw Monitoring with Limit,Pollutant of concern
Acute: NO WQS Limited data,No RP,Predicted Max z 50%of
Fluoride NC 1800 FW ug/L 2 1 1,364.4 Allowable Cw-apply monthly monitoring with limit
-----------------------------------------------
Note:n<9 Default C.V. Chronic: 1,800.0 Limited data,No RP,Predicted Max z 50%of
Limited data set No value>Allowable Cw Allowable Cw-apply monthly monitoring with limit
Acute: 75.487 RP for Limited Dataset(n<8)but 2 values>
Lead NC 2.9416 FW 75.4871 ug/L 2 2 52.302 Allowable Cw-apply Monthly Monitoring with Limit
Note:n<9 Default C.V. Chronic: 2.942 RP for Limited Dataset(n<8)but 2 values>
Limited data set 2 values >Allowable Cw Allowable Cw-apply Monthly Monitoring with Limit
Acute: NO WQS Limited Data(new Permit,New Waste Stream)-
Mercury NC 12 FW 0.5 ng/L 2 0 NO DETECTS apply Monthly Monitoring wth limit,Pollutant of
concern
Note:n<9 Chronic: 12.0 Limited Data(new Permit,New Waste Stream)-
apply Monthly Monitoring wth limit,Pollutant of
Limited data set Max MDL=200 concern
Acute: NO WQS No Data(new Permit,New Waste Stream)-apply
Molybdenum NC 2000 HH ug/L 0 0 N/A Monthly Monitoring with Limit,Pollutant of concern
--------------- ---------------------------
Chronic: 2,000.0 No Data(new Permit,New Waste Stream)-apply
Monthly Monitoring with Limit,Pollutant of concern
Acute(FW): 335.2 No Data(new Permit,New Waste Stream)-apply
Nickel NC 37.2313 FW 335.2087 µg/L Monthly Monitoring with Limit,Pollutant of concern
0 0 N/A Chronic(FW): 37.2 No Data(new Permit,New Waste Stream)-apply
Monthly Monitoring with Limit,Pollutant of concern
Nickel NC 25.0000 WS µg L Chronic(WS): 25.0 No Data(new Permit,New Waste Stream)-apply
Monthly Monitoring with Limit,Pollutant of concern
Acute: 56.0 apply Monthly Monitoring wth limit,Pollutant of
__ __Selenium NC 5 FW 56 ug/L 2 0 NO DETECTS _
Note:n<9 Chronic: 5.0 EimwileeTDa d(rTeW�i§�mit,-Mew WWs1e Str6arli-:—
apply Monthly Monitoring wth limit,Pollutant of
Limited data seJ Max MDL=10 nnnrprn
NCO090077 FW RPA,rpa
Page 14 of 16 7/27/2022

Irwin Creek Tributary to Remount Road Project - Outfall 001
NCO090077 Freshwater RPA- 95% Probability/95% Confidence Using Metal Translators Qw = 0.144 MGD
Acute: 0.296 apply Monthly Monitoring wth limit,Pollutant of
Silver NC 0.0(i FW 0.2964 ug/L 2 0 NO DETECTS _ _ _
Note:n 5 9 Chronic: 0.060 EimmiileeTDaCa(new mft,�lew Waste��ream�=—
apply Monthly Monitoring wth limit,Pollutant of
Limited data set Max MDL=5 Quamm
Acute: 125.7 No Data(new Permit,New Waste Stream)-apply
Zinc NC 126.7335 FW 125.7052 ug/L 0 0 N/A Monthly Monitoring with Limit,Pollutant of concern
-----------------------------------------
Chronic: 126.7 No Data(new Permit,New Waste Stream)-apply
Monthly Monitoring with Limit,Pollutant of concern
Acute: NO WQS
Nitrate/Nitrite as N mg/L 2 1 35.2 apply Monthly Monitoring wth limit,Pollutant of
Note:n<9 Default C.V. Chronic; Eim�iPeeFDaa(new-P§Fmit,-Mew Waste�'treamT=--
apply Monthly Monitoring wth limit,Pollutant of
Limited data set No value>Allowable Cw
Acute: NO WQS Limited Data(new Permit,New Waste Stream)-
Barium NC 21000 FW µg/L 2 2 2,312 apply Monthly Monitoring wth limit,Pollutant of
concern
Note:n 5 9 Default C.V. Chronic: 21000.0 Limited Data(new Permit,New Waste Stream)-
apply Monthly Monitoring wth limit,Pollutant of
Limited data set No value>Allowable Cw concern
Acute: NO WQS
Bromide mg,L 2 2 1.29
Note:n 5 9 1 Default C.V. Chronic: No Standard or Criteria,Present in groundwater,
Limited data set No value>Allowable Cw monitor monthly
Acute: NO WQS
Sulfate mg/L 2 2 1,720.7 __ _ _ ________ ---_________________________
Note:n<_9 Default C.V. Chronic:
No Standard or Criteria,Present,monitor monthly
Limited data set No value>Allowable Cw
NCO090077 FW RPA,rpa
Page 15 of 16 7/27/2022

Date: 7/27/2022
FACILITY: Irwin Creek Tributary to Remount Road Project Ou'
NPDES PERMIT: NCO090077 Dissolved to Total Metal Calculator
In accordance with Federal Regulations,permit limitations must be written as Total Metals per 40 CFR 122.45(c)
Receiving Receiving Rec.Stream NPDES Total Suspended Combined Combined Instream Instream Effluent
Upstream
Stream Stream Solids Hardness Hardness wastewater wastewater Hardness
1010 Flow Limit Hardness
summer summer 7Q10 -Fixed Value- chronic Acute Concentration Concentration Average
7010(CFS) (MGD) [MGD] [MGD] (mg/L) (mg/L) (mg/L) (Chronic) (Acute) Average(mg/L) (mg/L)
0.0000 0.0000 0.0000 0.1440 10 25.000 100.0000 100.0000 25 25
Upstream Hard Avg(mg/L)= 25
EFF Hard Avg(mg/L)= 25
US EPA Maximum Allowable Effluent Concentration COMMENTS(identify parameters to PERCS Branch to maintain in facility's LTMP/STMP):
Dissolved Metals Translators-using (MAEC)as a Total Metal
PARAMETER Default Partition =Dissolved Metal Translator
Chronic Acute Coefficients Chronic Acute
[ug/1] I [ug/1] streams [ug/1] [ug/1]
Cadmium(d) 0.15 0.82 0.252 0.59 3.24
Cd-Trout strea 0.15 0.252 0.59 2.01
Chromium III(d)(h) 24 183 0.202 117.73 905.08
Chromium VI(d) 11 16 1.000 11.00 16.00
Chromium,Total(t) N/A N/A
Copper(d)(h) 2.7 3.6 0.348 7.88 10.47
Lead(d)(h) 0.54 14 0.184 2.94 75.49
Nickel(d)(h) 16 145 0.4321 37.23 335.21
Ni-WS streams(t) 25
Silver(d)(h,acute) 0.06 0.30 1.000 0.06 0.30
Zinc(d)(h) 1 36 36 0.2881 126.73 125.71
Beryllium 6.5 651 1.0001 6.5
Arsenic(d) 1501 3401 1.000 150
(d)=dissolved metal standard.See 15A NCAC 02B.0211 for more information.
(h)=hardness-dependent dissolved metal standard.See 15A NCAC 02B.0211 for more information.
(t)=based upon measurement of total recoveable metal.See 15A NCAC 02B.0211 for more information.
The Human Health standard for Nickel in Water Supply Streams is 25 mg/L which is Total Recoverable metal standard.
The Human Health standard for Arsenic is 10 µg/L which is Total Recoverable metal standard.

NC DIVISION OF WATER RESOURCES
NPDES Implementation of Instream Dissolved Metals Criteria
The NC 2007-2014 Water Quality Standard(WQS) Triennial Review was approved by the NC
Environmental Management Committee(EMC)on November 13, 2014. The US EPA subsequently
approved the WQS revisions on April 6,2016 with some exceptions. All permits public noticed by the
NC Division of Water Resources NPDES Permitting Unit after April 6,2016 shall include the
implementation of the approved 2007-2014 Triennial Review Rules for freshwater and saltwater water
quality criteria.
Table 1.NC Dissolved Metals Water ualit Criteria/A uatic Life Protection
Parameter Acute FW,ug/1 Chronic FW,ug/1 Acute SW,ug/1 Chronic SW,ug/1
(Dissolved) (Dissolved) (Dissolved) (Dissolved)
Arsenic 340 150 69 36
Beryllium 65 6.5 --- ---
Cadmium Calculation Calculation 40 8.8
Chromium III Calculation Calculation --- ---
Chromium VI 16 11 1100 50
Copper Calculation Calculation 4.8 3.1
Lead Calculation Calculation 210 8.1
Nickel Calculation Calculation 74 8.2
Silver Calculation 0.06 1.9 0.1
Zinc Calculation Calculation 90 81
Table 1 Notes:
1. FW=Freshwater, SW=Saltwater
2. Calculation=Hardness dependent criteria
3. Only the aquatic life criteria listed above are in dissolved form. Mercury and selenium criteria
have been retained as Total Metals criteria due to bioaccumulative concerns. It is still necessary
to evaluate total recoverable criteria for human health. NC has also retained the existing toxic
criteria listed in 15A NCAC 2B.0200(e.g.,arsenic at 10 ug/1 for human health protection),
cyanide,fluoride.
Table 2.Dissolved Freshwater Standards for Hardness-Dependent Metals
The Water Effects Ratio (WER) is equal to one unless determined otherwise under 15A
NCAC 02B .0211 Subparagraph(11)(d)
Metal NC Dissolved Standard, ug/I
Cadmium,Acute {1.136672-[ln hardness](0.041838)} e^{0.9151 [In hardness]-3.1485}
Cadmium, Acute {1.136672-[ln hardness](0.041838)} e^{0.9151[ln hardness]-3.623 61
Trout waters
Cadmium,Chronic {1.101672-[ln hardness](0.041838)} •e^{0.7998[ln hardness]-4.4451}
Chromium III,Acute 0.316 e^{0.8190[ln hardness]+3.7256}
Chromium III, 0.860 e^{0.8190[ln hardness]+0.6848}
Chronic
Copper,Acute 0.960 e^{0.9422[ln hardness]-1.700}
Copper,Chronic 0.960 e^{0.8545[ln hardness]-1.702}
Lead,Acute {1.46203-[ln hardness](0.145712)} •e^{1.273[ln hardness]-1.460}
Lead,Chronic {1.46203-[ln hardness](0.145712)} •e^{1.273[ln hardness]-4.705}
Page 1 of 4

Nickel,Acute 0.998 e^{0.8460[ln hardness]+2.255}
Nickel,Chronic 0.997 e^{0.8460[ln hardness]+0.0584}
Silver,Acute 0.85 •eA{1.72[ln hardness]-6.59}
Silver,Chronic Not applicable
Zinc,Acute 0.978 eA{0.8473[ln hardness]+0.884}
Zinc,Chronic 0.986 eA{0.8473[ln hardness]+0.884}
RPA Permitting Guidance/WQBELs for Hardness-Dependent Metals -Freshwater
The Reasonable Potential Analysis (RPA) is designed to calculate the allowable instream concentrations
for permit limitations. Limitations are required based upon a showing of"reasonable potential' to exceed
water quality standards. If monitoring for a particular pollutant indicates that the pollutant is not present
(i.e. consistently below detection level),then the Division may remove the monitoring requirement in the
reissued permit.
1. To perform a RPA on the Freshwater hardness-dependent metals the Permit Writer compiles the
following information:
• Critical low flow of the receiving stream, 7Q 10(the spreadsheet automatically calculates
the 1 Q 10 using the formula 1 Q 10=0.843 (7Q 10)0.993)
• The mean annual receiving stream flow(QA), for carcinogen comparisons against HH
criteria
• The minimum average flow over 30 consecutive days that has an average recurrence of
once in two years (30Q2)in the receiving stream, for comparisons against aesthetic
standards
• effluent hardness and upstream hardness, site-specific data is preferred
• Permitted flow
• Receiving stream classification
2. The chronic Aquatic Life water quality criteria is converted from total recoverable metal at lab
conditions to dissolved lab conditions for the following metals: cadmium, copper, lead,nickel,
zinc, and trivalent chromium. EPA default partition coefficients, or site-specific translators
developed using federally approved methodology,are used in the RPA spreadsheet to convert the
dissolved lab conditions to a total recoverable metal at ambient conditions.
3. The acute Aquatic Life water quality criteria is converted from total recoverable metal at lab
conditions to dissolved lab conditions for the following metals: cadmium, copper, lead,nickel,
zinc, silver and trivalent chromium. EPA default partition coefficients,or site-specific translators
developed using federally approved methodology, are used in the RPA spreadsheet to convert the
dissolved lab conditions to a total recoverable metal at ambient conditions.
4. For criteria that are hardness dependent, site-specific hardness data(effluent and upstream) is best
to evaluate chronic and acute concentrations. The permit writer will first review DMR's,Effluent
Pollutant Scans,and Toxicity Test results for any hardness data and then contact the Permittee to
see if any additional data is available for instream hardness values,upstream of the discharge.
If no hardness data is available,the permit writer may choose to do an initial evaluation using a
default hardness of 25 mg/L and total suspended solids(TSS)of 10 mg/L to see if the permittee is
impacted.Minimum and maximum limits on the hardness value used for water quality
calculations are 25 mg/L and 400 mg/L respectively. The minimum TSS value used for EPA
partition coefficients is 10 mg/L.
Page 2 of 4

If the use of a default hardness value results in a hardness-dependent metal showing reasonable
potential to violate water quality criteria the permit writer should contact the Permittee and
request 5 site-specific effluent and upstream hardness samples.
The overall hardness value used in the water quality calculations is calculated as follows:
Combined Hardness(chronic)
_(Permitted Flow*Avg. Effluent Hardness) 7Q10 S*Avg.Upstream Hardness)
(Permitted flow+7Q10 S)
The Combined Hardness for acute is the same but the calculation uses the IQ 10 flow.
5. EPA default partition coefficients or the"Fraction Dissolved"converts the value for dissolved
metal at laboratory conditions to total recoverable metal at in-stream ambient conditions. This
factor is calculated using the linear partition coefficients found in The Metals Translator:
Guidance for Calculating a Total Recoverable Permit Limit from a Dissolved Criterion (EPA
823-B-96-007,June 1996) and the equation:
Cdiss - 1
Ctotal 1 + } [Kp.] [ss(t+,] [10-6] }
Where: ss=in-stream suspended solids concentration[mg/1],minimum of 10 mg/L used
Kpo and a=constants that express the equilibrium relationship between dissolved and
adsorbed forms of metals.A list of constants used for each hardness-dependent metal can
also be found in the RPA program under a sheet labeled DPCs.
6. The dissolved hardness-dependent metals calculations are divided by the default partition
coefficients(or translators)to obtain a Total Recoverable Metal at ambient conditions. Dissolved
metals that do not have translators or default partition coefficients are divided by one. All other
standards(HH,WS,non-hardness dependent metals)are automatically shown in Table 2 of the
RPA spreadsheet when the program is initiated.
7. The standards, criteria, and calculated Total Recoverable metals listed in Table 2 of the RPA
spreadsheet are inserted into a mass balance equation to determine the total allowable
concentration(permit limits) for each pollutant using the following equation:
Ca=(s7Q10+Qw) (Cwgs)—(s7Q10)(Cb)
QW
Where: Ca=allowable effluent concentration(µg/L or mg/L)
Cwqs=NC Water Quality Standard or federal criteria
Cb=background concentration(assume zero for all toxicants except NH3)*
Qw=permitted effluent flow
S7Q10=summer low flow used to protect aquatic life from chronic toxicity and human
health through the consumption of water, fish,and shellfish from noncarcinogens
* Discussions are on-going with EPA on how best to address background concentrations
Flows other than S7Q10 may be incorporated as applicable:
IQ 10=used in the equation to protect aquatic life from acute toxicity
QA=used in the equation to protect human health through the consumption of water, fish,
and shellfish from carcinogens
30Q2=used in the equation to protect aesthetic quality
The total allowable concentration(permit limits)are shown on the"RPA Sheet"in the RPA
spreadsheet.
Page 3 of 4

8. Effluent toxicant data is entered into the"Data Sheet."of the RPA spreadsheet which uses
statistics to estimate the 95t'percentile concentration of each pollutant. These concentrations are
listed as the Predicted max concentrations on the"RPA Sheet"in the RPA spreadsheet. The
Predicted Max concentrations are compared to the Total allowable acute and chronic
concentrations to determine if a permit limit is necessary. This is in accordance with the U.S.
EPA Technical Support Document for Water Quality-Based Toxics Control published in 1991.
9. Effluent hardness sampling and instream hardness sampling,upstream of the discharge, is being
inserted into all permits with facilities monitoring for hardness-dependent metals to build a more
robust hardness dataset.
10. Hardness and flow values used in the Reasonable Potential Analysis for this permit included:
Parameter Value Comments
Effluent Hardness(mg/L) 25 mg/L Default value
[Total as, CaCO3 or(Ca+Mg)]
Upstream Hardness(mg/L) 25 mg/L Default value
[Total as, CaCO3 or(Ca+Mg)]
7Q10 summer(cfs) 0 Discharge near UT to Irwin Creek,
zero flow conditions
1 Q 10 (cfs) 0 Discharge near UT to Irwin Creek,
zero flow conditions
Permitted Flow(MGD) 0.144 MGD Permit application
11. The Total Chromium NC WQS was removed and replaced with trivalent chromium and
hexavalent chromium WQC. Effluent sampling data on Total Chromium is used as a surrogate
parameter to assess if limitations and/or sampling are required for trivalent or hexavalent
chromium.
Date: 07/27/2022
Permit Writer: Derek Denard
Page 4 of 4

;a. State of North Carolina
Division of Water Resources
Water Quality Regional Operations Section
Environmental Staff Report
Quality
To: ®NPDES Unit Application No.: (NC0090077)
Attn: (Derek Denard in Raleigh)
Facility name: Former Southside Pre-Regulatory Landfill- Excavation& Dewatering(Former Southside Landfill)
From: (Edward Watson in Regional Office)
Mooresville Regional Office
Note: This form has been adapted from the non-discharge facility staff report to document the review of both non-
discharge and NPDES permit applications and/or renewals. Please complete all sections as they are applicable.
I. GENERAL AND SITE VISIT INFORMATION
1. Was a site visit conducted? ®Yes or❑No
a. Date of site visit: 01/31/2022
b. Site visit conducted by: Edward Watson
c. Inspection report attached? ❑ Yes or®No
d. Person contacted: Bruce Reilly,P.E., and their contact information: [phone] ext.
e. Driving directions: From the MRO office, travel South on Main St. for 2.7 miles to Langtree Rd. Turn right onto
Langtree Rd and travel for— 1.1 miles. Take on ramp. to I-77 on ramp South toward Charlotte. Drive S. on I-77 for
—22 miles. To exit 9 to Wilkson Blvd./US-74 E toward John Belk Frwy/West Blvd/1-277 E. for—0 .25 miles,then
bear left following the ramp to onto Barringer Dr. Stay on Barringer Dr. for 0.43 miles,then turn left onto Remount
Rd. Travel on Remount Rd for 0.5 miles then turn right onto Toomey Ave. The site is on the left across from the
Charlotte Human Society. Total trip miles—29.5 miles.
2. Discharge Point(s):001 and 002
001 Latitude: 35' 12' 28.61" Longitude: 80' 52' 29.56"
002 Latitude: 35' 12' 28.86" Longitude: 80' 52' 30.36"
3. Receiving stream or affected surface waters: UT to Irwin Creek
Classification: C 11-137-1
River Basin and Subbasin No. 03050103 Sugar Creek Subbasin
Describe receiving stream features and pertinent downstream uses: Catawba River Basin
II. PROPOSED FACILITIES: NEW APPLICATIONS
1. Facility Classification: Minor (Please attach completed rating sheet to be attached to issued permit)
Proposed flow:0.144 MGD
Current permitted flow:New Application
2. Are the new treatment facilities adequate for the type of waste and disposal system? ® Yes or❑No
If no, explain:
3. Are site conditions(soils, depth to water table, etc.)consistent with the submitted reports? ® Yes ❑No ❑N/A
If no,please explain: Soil conditions were not examined as no open trenches were present to be able to observe
onsite soil conditions. Analysis was based on file review of multiple site soil borings.
FORM: WQROSSR 04-14 Pagel of 3

4. Do the plans and site map represent the actual site (property lines,wells, etc.)? ® Yes ❑ No ❑ N/A
If no,please explain:
5. Is the proposed residuals management plan adequate? ❑ Yes ❑ No ® N/A
If no,please explain:
6. Are the proposed application rates(e.g., hydraulic,nutrient) acceptable? ❑ Yes ❑ No ®N/A
If no,please explain:
7. Are there any setback conflicts for proposed treatment, storage and disposal sites? ❑ Yes or® No
If yes, attach a map showing conflict areas.N/A.
8. Is the proposed or existing groundwater monitoring program adequate? ❑ Yes ®No ❑N/A
If no, explain and recommend any changes to the groundwater monitoring program: Please refer to the
Additional Regional Office Comments for sampling recommendations.
9. For residuals,will seasonal or other restrictions be required? ❑ Yes ❑ No ❑ N/A
If yes, attach list of sites with restrictions(Certification B)
Describe the residuals handling and utilization scheme: N/A.
10. Possible toxic impacts to surface waters: Acute toxicity testing will be in place to monitor breakthrough of
Chlorinated Solvents being treated by the on-site system.
11. Pretreatment Program(POTWs only): N/A.
III.REGIONAL OFFICE RECOMMENDATIONS
1. Do you foresee any problems with issuance/renewal of this permit? ❑ Yes or® No
If yes,please explain:
2. List any items that you would like the NPDES Unit or Non-Discharge Unit Central Office to obtain through an
additional information request:
Item Reason
1 Please provide a topographic map that displays the direction of GW flow.
2 Please provide iso-contour maps of the constituents of concern to be treated by
the system.
3. List specific special conditions or compliance schedules recommended to be included in the permit when issued:
Condition Reason
1 Acute toxicity sampling due to the presence of chlorinated solvents.
2 8 RCRA metals to be sampled due to past site activity.
3 Sampling to be conducted or VOC and SVOC compounds due to previous near
site activities.
FORM: WQROSSR 04-14 Page 2 of 3

4. Recommendation: ❑ Hold,pending receipt and review of additional information by regional office
® Hold,pending review of draft permit by regional office
❑ Issue upon receipt of needed additional information
❑ Issue
❑ Deny(Please state reasons: )
5. Signature of report preparer: Edward Watson,Hydrogeologist 02/14/2022.
Docu Signed by:
[44uw H pzu
2.14.22
6. Signature of regional supervisor: F161Fe69A2D84A3... Date:
ADDITIONAL REGIONAL STAFF REVIEW ITEMS
The Pre-Regulatory Landfill has been assigned INSB site#NONCD000807.The site is listed as a Superfund site.
There is observed C&D type material exposed in the wooded area of the property behind the parking lot. Also,there is documentation
of 55-gallon drums containing Lead and Chromium waste on the property. The Site Summary Report for July 21,2021 prepared by
Schnabel Engineering South,P.C.of Greensboro N.C.IHSB DOC#SF_F NONCD0000807_07-21-2010_IHS_LR.
The information for the nearby sites indicates the former presence of several Gas Stations and Automotive Service facilities with
former USTs, several Former Dry Cleaning facilities,a Construction Company,and the Former Pre-regulatory Southside Ash
Landfill.
A review of the DWM Site Locator Web Browser Tool,indicates several potential sources of contaminates near and around the
subject site.A documents review revealed that an unknown quantity of Hazardous waste was stored within the former Industrial
Crankshaft&Engineering Co,Inc. facility d/b/a/Dynatech Industries Site located at 2213 Toomey Ave., Charlotte. This facility is
listed as a Superfund/Inactive Section facility within permit#NCD9811014517.
Assessment documents were reviewed associated with these former facilities. The documents include GW Chemistry data that was
available on the Division of Waste Management Site Locator Tool.
Many of these facilities have received NFA status from DWM for a variety of reasons.
GW analytical data from existing monitor wells indicate petroleum constituents present at levels above 2L or PSRG Soil Standards.
There are no water supply wells found to be located on the property.
FORM: WQROSSR 04-14 Page 3 of 3

Beaufort Gazette The Herald-Pock Hill el Nuevo Herald-Miami Sun News-Myrtle Beach
Belleville News-DernDcrat Herald Sun-Durham Modesto Bee The Neees Tnb une Tacoma
Iralenton Herald Island packet The Olympian San Luis Obispo Tribune
ANVMCCLATCHY Centre
Bellingham Herald Idaho Statesman Raleigh News&Observer The Telegraph-Macon
ColumbusCharlotte Cbsener Lexington Herald-Leader Fort Worth Star-Telegram Wichita Eagle
Sun-Star
Fresrvo Bee Miami Heiald Sun Herald-Biloxi
AFFIDAVIT OF PUBLICATION
Account# Order Number Identification Order PO Amount Cols Depth
28386 304106 Print Legal Ad-IPL0085519 $636.66 2 26 L
Attention: Wren Thedford North Carolina } SS
NCDENR/DWO/POINT SOURCE Mecklenburg County }
1617 MAIL SERVICE CENTER Before the undersigned,a Notary Public of said
RALEIGH,NC 276991677 County and State,duly authorized to administer
oaths affirmations,etc.,personally appeared,
being duly sworn or affirmed according to law,
- - - - cloth depose and
d say that he/she is a
Public Notice p y
North Carolina Environmental Management Commission/NPDES Unit representative of The Charlotte Observer
1617 Mail Service Center
Raleigh.NC 27699 1617 Publishing Company,a corporation organized and
Notice of Intent to Issue a NPDES Wastewater Permit NCO090077 Irwin Creek Remediation Site doing business under the laws of the State of
The North Carolina Environmental Management Commission proposes to issue Delaware,and publishing a newspaper known as
a NPDES wastewater discharge permit to the persons) listed below. Written The Charlotte Observer in the city of Charlotte,
comments regarding the proposed permit will be accepted until 30 days after County of Mecklenburg,and State of North
the publish date of this notice.The Director of the NC Division of Water Resourc-
es(DWR) may hold a public hearing should there be a significant degree of Carolina and that as such he/she is familiar with
public interest.Please mail comments and/or information requests to DWR at
the above address.Interested persons may visit the DWR at 512 N.Salisbury the books,records,files,and business of said
Street.Ra"h,NC 27604 to review information on file.Additional information on Corporation and by reference to the files of said
NPDES permits and this notice may be found on our website:httpl/deq.nc.gov/
about/divisions/water-resources/water-resources-permits/wastewater-branch/ publication,the attached advertisement was
npdes-wastevater/public-notices.or by calling(919)707-3601. Charlotte Water
[5100 Brookshire Boulevard,Charlotte,NC 282161 has requested a new per- inserted.The following is correctly copied from
mit NCO090077 for its Irwin Creek Tributary to Remount Rd Sewer Project in the books and files of the aforesaid Corporation
Mecklenburg County. This permitted facility discharges treated construction
dewatering groundwater to Irwin Creek in the Catawba River Basin.Some of and Publication.
the parameters in the permit are water quality limited.This discharge may affect
future allocations in this segment of Irwin Creek.
IPL0085519
Aug 14 2022 No.of Insertions: 1
Beginning Issue of: 08/14/2022
Ending Issue of: 08/14/2022
I
X�
In Testimony Whereof I have hereunto set my hand
and affixed my seal on the 15th day of August,2022
Notary Public in and for the state of Texas,residing in
Dallas County
N My NOW 1D 01317%951
Ede M October 21,20n
Extra charge for lost or duplicate affidavits.
Legal document please do not destroy.

10/6/22, 11:03 PM Mail-Denard, Derek-Outlook
Re: DRAFT Permit NCO090077 - Charlotte Water - Irwin Creek remediation site
Denard, Derek <[e-mail]>
Thu 10/6/2022 10:59 PM
To:Watson, Edward M <[e-mail]>
Ed,
Sorry I missed your question. They would have to qualify for a wavier from eDMR. Currently no one the
state has I wavier that I can think of. They all have internet. I don't think they would have strong enough
argument not to report electronically. Otherwise, electronic reporting is a a condition of their permit.
Thanks,
Derek C. Denard
Environmental Program Consultant, Division of Water Resources
North Carolina Department of Environmental Quality
Office: [phone]
[e-mail]
...ID E
Department of Environmental Dualdy
Email correspondence to and from this address is subject to the North
Carolina Public Records Law and may be disclosed to third parties.
From: Watson, Edward M <[e-mail]>
Sent: Monday,August 1, 2022 8:06 AM
To: Denard, Derek<[e-mail]>
Subject: RE: DRAFT Permit NCO090077-Charlotte Water- Irwin Creek remediation site
Derek,
The draft permit looks good. I just have a question. In the event that our system is not able to accept eDMRs, can
the permittee or their representative have the option to submit the eDMR manually to be able to maintain
compliance with reporting?
Ed
From: Denard, Derek<[e-mail]>
Sent: Friday,July 29, 2022 1:52 PM
To:Watson, Edward M <[e-mail]>
https://outlook.office365.com/mail/sentitems/id/AAQkADdhYTVmZDBILTE5ZDctNG15MCO4ZjliLWU4MjVhZTBhMmJkMgAQAN6wVWIIFNhBkdUfTOC... 1/2

10/6/22, 11:03 PM Mail-Denard, Derek-Outlook
Cc: Hennessy,John <john.hen [e-mail]>; Dowden, Doug<[e-mail]>
Subject: DRAFT Permit NCO090077-Charlotte Water- Irwin Creek remediation site
Ed,
Please find the attached draft permit NCO090077 and fact sheet for the Charlotte Water- Irwin Creek
remediation site. I plan to submit the draft for public notice on August 9, 2022. If you have any
comments, please let me know.
Thanks,
Derek
Derek C. Denard
Environmental Program Consultant
N.C. Division of Water Resources
N.C. Department of Environmental Quality
919 707 3618 office
919 707 9000 main DWR
[e-mail]
Water Quality Permitting Section - NPDES
1617 Mail Service Center
Raleigh, NC 27699-1617
Email correspondence to and from this address is subject to the
North Carolina Public Records Law and may be disclosed to third parties.
https://outlook.office365.com/mail/sentitems/id/AAQkADdhYTVmZDBILTE5ZDctNG15MCO4ZjliLWU4MjVhZTBhMmJkMgAQAN6wVW I I FNhBkdUfTOC... 2/2

10/6/22, 11:25 PM Mail-Denard, Derek-Outlook
Re: Draft NPDES Permit NCO090077 - Irwin Creek Tributary to Remount Road Project
Denard, Derek <[e-mail]>
Tue 8/9/2022 3:28 PM
To:Wiggins, Kent <[e-mail]>
Kent,
Tom Moore keeps us updated on a current list of parameter codes:
https: reports.ncdenr.org BOE OpenDocument/2002150408/CrystalReports/viewrpt.cwr?
id=7848&promptexO=DMR&apsuser=BIMS U&ap5password=b10Ms cr%28ddnri59%29&ap5authtype=s
ecEnterprise&cmd=EXPORT&EXPORT FMT=U2FPDF%3AO
Available Parameters for DMRs (as of 712712022)
Parameter Code Parameter Description Parameter Abbreviation 30354 123789HXCDF 1,2,3,7,8,9-
hexachlorodibenzofuran C0551 124-TCB CONC 1,2,4-TrichIorobenzene - Concentration
reports.ncdenr.org
Derek C. Denard
Environmental Program Consultant
N.C. Division of Water Resources
N.C. Department of Environmental Quality
919 707 3618 office
919 707 9000 main DWR
[e-mail]
Water Quality Permitting Section - NPDES
1617 Mail Service Center
Raleigh, NC 27699-1617
Email correspondence to and from this address is subject to the
North Carolina Public Records Law and may be disclosed to third parties.
From: Wiggins, Kent<[e-mail]>
Sent:Tuesday,August 9, 2022 3:23 PM
To: Denard, Derek<[e-mail]>
Subject: FW: Draft NPDES Permit NCO090077- Irwin Creek Tributary to Remount Road Project
Derek,
https://outlook.office365.com/mail/id/AAQkADdhYTVmZDBILTE5ZDctNG15MC04ZjliLWU4MjVhZTBhMmJkMgAQAMEcUzOCF9ZEgv2Vgxw%2FM41%... 1/9

10/6/22, 11:25 PM Mail-Denard, Derek-Outlook
I added the sentence to TAA6C, I don't see TAA3E in our list. Zach said it might have been phased out. Do we
have an updated Parameter code list other than the one Zach attached. Trying to make sure I'm not missing one
or more in the library.
Kent
Kent Wiggins, PEM
Division of Water Resources
Office Phone [phone]-currently not used
Cell-919-630-8657
From:Thomas,Zachary T<[e-mail]>
Sent:Tuesday,August 9, 2022 3:14 PM
To:Wiggins, Kent<[e-mail]>
Cc: Moore, Cindy<[e-mail]>
Subject: RE: Draft NPDES Permit NCO090077- Irwin Creek Tributary to Remount Road Project
It's possible we have 'phased that one out'—I just noticed the template in the NPDES folder, but it was an older
date and wanted to include just in case.
I attached the parameter codes list that we have above (I'm not sure if there has been an updated one by
permitting), please let me know if you all have another one and we can compare.
Thank you,
Zach Thomas
Environmental Specialist II
Aquatic Toxicology Branch, Compliance and Enforcement
NCDEQ—Division of Water Resources—Water Sciences Section
Based on the current guidance to minimize the spread of COVID-19,the Department of Environmental Quality has
adjusted operations to protect the health and safety of the staff and public. Many employees are working
remotely or are on staggered shifts.To accommodate these staffing changes, all DEQ office locations are limiting
public access to appointments only. Please check with the appropriate staff before visiting our offices, as we may
be able to handle your requests by phone or email. We appreciate your patience as we continue to serve the
public during this challenging time.
919.743.8441 **New Office Number**
919.743.8517 Fax
zachary.thomas(@ncdenr.gov
1621 Mail Service Center
Raleigh, NC 27699-1621
Submit ATForms electronically to:[e-mail]
c:e;0"D_E Q1
\/0`1�),
Email correspondence to and from this address is subject to the North Carolina Public Records Law
and may be disclosed to third parties.
From: Wiggins, Kent<kent.wiggins ncdenr.gov>
Sent:Tuesday,August 9, 2022 3:06 PM
https://outlook.office365.com/mail/id/AAQkADdhYTVmZDBILTE5ZDctNG15MC04ZjliLWU4MjVhZTBhMmJkMgAQAMEcUzOCF9ZEgv2Vgxw%2FM41%... 2/9

10/6/22, 11:25 PM Mail-Denard, Derek-Outlook
To:Thomas, Zachary T<[e-mail]>
Subject: RE: Draft NPDES Permit NCO090077- Irwin Creek Tributary to Remount Road Project
Sure thing. I think I need you to cross check between the two list. I don't see a TAA3E in the new list. I may be
just getting confused but If you would check I'd appreciate it.
Thanks,
Kent
Kent Wiggins, PEM
Division of Water Resources
Office Phone [phone]-currently not used
Cel I-919-630-8657
From:Thomas,Zachary T<zachary.thomas(@ncdenr.gov>
Sent:Tuesday,August 9, 2022 3:03 PM
To:Wiggins, Kent<kent.wiggins ncdenr.gov>
Cc: Moore, Cindy<[e-mail]>
Subject: RE: Draft NPDES Permit NCO090077- Irwin Creek Tributary to Remount Road Project
Hi Kent,
Thanks for sharing that link and for helping us out with the language change. Let me know if you need anything
else.
Thank you,
Zach Thomas
Environmental Specialist II
Aquatic Toxicology Branch, Compliance and Enforcement
NCDEQ—Division of Water Resources—Water Sciences Section
Based on the current guidance to minimize the spread of COVID-19,the Department of Environmental Quality has
adjusted operations to protect the health and safety of the staff and public. Many employees are working
remotely or are on staggered shifts.To accommodate these staffing changes, all DEQ office locations are limiting
public access to appointments only. Please check with the appropriate staff before visiting our offices, as we may
be able to handle your requests by phone or email. We appreciate your patience as we continue to serve the
public during this challenging time.
919.743.8441 **New Office Number**
919.743.8517 Fax
[e-mail]
1621 Mail Service Center
Raleigh, NC 27699-1621
Submit ATForms electronically to:[e-mail]
D_E\/1",
Q�
Email correspondence to and from this address is subject to the North Carolina Public Records Law
and may be disclosed to third parties.
https://outlook.office365.com/mail/id/AAQkADdhYTVmZDBILTE5ZDctNG15MC04ZjliLWU4MjVhZTBhMmJkMgAQAMEcUzOCF9ZEgv2Vgxw%2FM41%... 3/9

10/6/22, 11:25 PM Mail-Denard, Derek-Outlook
From: Wiggins, Kent<kent.wiggins ncdenr.gov>
Sent:Tuesday,August 9, 2022 2:30 PM
To:Thomas, Zachary T<zachary.thomas@ cdenr.gov>; Denard, Derek<[e-mail]>
Cc: Moore, Cindy<[e-mail]>; Hennessy,John <john.hennessy_@ncdenngov>
Subject: RE: Draft NPDES Permit NCO090077- Irwin Creek Tributary to Remount Road Project
Zach,
The IWC would most likely vary from permit to permit so we put that as a highlighted segment meaning that it is
something the permit writers would change as needed, like the months in the case of quarterly monitoring.
We have a new special conditions library NPDES Spec Cond Library.docx. We have placed all the special
conditions we have found so far in this file and tried to organize them. There is a clickable table of contents.
We put the latest version that we talked about at that site but I think it is pretty much the same as what is in the
template files.
It seems like a necessary part of the condition to have the IWC included. I'll add it to those two conditions as long
as John is in agreement.
Thanks,
Kent
Kent Wiggins, PEM
Division of Water Resources
Office Phone [phone]-currently not used
Cell-919-630-8657
From:Thomas,Zachary T<[e-mail]>
Sent:Tuesday,August 9, 2022 1:58 PM
To:Wiggins, Kent<kent.wiggins ncdenr.gov>; Denard, Derek<[e-mail]>
Cc: Moore, Cindy<[e-mail]>; Hennessy,John <john.hennessy_@ncdenngov>
Subject: RE: Draft NPDES Permit NCO090077- Irwin Creek Tributary to Remount Road Project
Hi Kent,
Yes,that's the sentence we were thinking of. I'm not sure what the IWC for this one would be (probably 90% if its
going to a UT) but it would be beneficial for the facility and lab to have that dilution starting point.
I found what I think is the template folder and most of them seem to have that same language except for the
TAA6C and TAA3E.
Thank you,
Zach Thomas
Environmental Specialist II
Aquatic Toxicology Branch, Compliance and Enforcement
NCDEQ—Division of Water Resources—Water Sciences Section
Based on the current guidance to minimize the spread of COVID-19,the Department of Environmental Quality has
adjusted operations to protect the health and safety of the staff and public. Many employees are working
remotely or are on staggered shifts.To accommodate these staffing changes, all DEQ office locations are limiting
public access to appointments only. Please check with the appropriate staff before visiting our offices, as we may
be able to handle your requests by phone or email. We appreciate your patience as we continue to serve the
public during this challenging time.
https://outlook.office365.com/mail/id/AAQkADdhYTVmZDBILTE5ZDctNG15MC04ZjliLWU4MjVhZTBhMmJkMgAQAMEcUzOCF9ZEgv2Vgxw%2FM41%... 4/9

10/6/22, 11:25 PM Mail-Denard, Derek-Outlook
919.743.8441 **New Office Number**
919.743.8517 Fax
[e-mail]
1621 Mail Service Center
Raleigh, NC 27699-1621
Submit ATForms electronically to:[e-mail]
D_E
a�.._.,_......o..1
Email correspondence to and from this address is subject to the North Carolina Public Records Law
and may be disclosed to third parties.
From: Wiggins, Kent<[e-mail]>
Sent:Tuesday,August 9, 2022 11:11 AM
To:Thomas, Zachary T<[e-mail]>; Denard, Derek<[e-mail]>
Cc: Moore, Cindy<[e-mail]>; Hennessy,John <john.henness ncdenr.gov>
Subject: RE: Draft NPDES Permit NCO090077- Irwin Creek Tributary to Remount Road Project
Zach,
Is this the sentence we are talking about?
"The effluent concentration at which there may be at no time significant acute mortality is 90% (defined as
treatment two in the procedure document)."
I don't see the term"instream waste concentration(ICW)" used but this appears in other conditions.
Let me know if this is what you are looking for and where you want it to go. Also could you take a look and make
sure it is in all the others if needed.
Thanks,
Kent
Kent Wiggins, PEM
Division of Water Resources
Office Phone [phone]-currently not used
Cell-919-630-8657
From:Thomas,Zachary T<[e-mail]>
Sent:Tuesday,August 9, 2022 10:39 AM
To:Wiggins, Kent<kent.wiggins ncdenr.gov>; Denard, Derek<[e-mail]>
Cc: Moore, Cindy<[e-mail]>
Subject: RE: Draft NPDES Permit NCO090077- Irwin Creek Tributary to Remount Road Project
Hi Kent,
Cindy and I think it would be helpful for all parties (lab/facility/etc.) if it had the IWC as a good starting point for
them to go off of to make sure they hit the right dilutions for the LC50 tests.
Let me know how we can help with this!
Thank you,
Zach Thomas
https://outlook.office365.com/mail/id/AAQkADdhYTVmZDBILTE5ZDctNG15MC04ZjliLWU4MjVhZTBhMmJkMgAQAMEcUzOCF9ZEgv2Vgxw%2FM41%... 5/9

10/6/22, 11:25 PM Mail-Denard, Derek-Outlook
Environmental Specialist II
Aquatic Toxicology Branch, Compliance and Enforcement
NCDEQ—Division of Water Resources—Water Sciences Section
Based on the current guidance to minimize the spread of COVID-19,the Department of Environmental Quality has
adjusted operations to protect the health and safety of the staff and public. Many employees are working
remotely or are on staggered shifts.To accommodate these staffing changes, all DEQ office locations are limiting
public access to appointments only. Please check with the appropriate staff before visiting our offices, as we may
be able to handle your requests by phone or email. We appreciate your patience as we continue to serve the
public during this challenging time.
919.743.8441 **New Office Number**
919.743.8517 Fax
zachary.thomas(@ncdenr.gov
1621 Mail Service Center
Raleigh, NC 27699-1621
Submit ATForms electronically to:[e-mail]
Email correspondence to and from this address is subject to the North Carolina Public Records Law
and may be disclosed to third parties.
From: Wiggins, Kent<kent.wiggins ncdenr.gov>
Sent:Tuesday,August 9, 2022 10:36 AM
To: Denard, Derek<[e-mail]>;Thomas, Zachary T<[e-mail]>
Cc: Moore, Cindy<[e-mail]>
Subject: RE: Draft NPDES Permit NCO090077- Irwin Creek Tributary to Remount Road Project
Zach,
Let me know if we need to make a change. Is there a reason we may have left it off this one or did I just miss it.
Kent
Kent Wiggins, PEM
Division of Water Resources
Office Phone [phone]-currently not used
Cell-919-630-8657
From: Denard, Derek<[e-mail]>
Sent:Tuesday,August 9, 2022 10:11 AM
To:Thomas, Zachary T<[e-mail]>
Cc: Moore, Cindy<[e-mail]>; Wiggins, Kent<kent.wiggins ncdenr.gov>
Subject: Re: Draft NPDES Permit NCO090077- Irwin Creek Tributary to Remount Road Project
Zach,
I am not sure why the FW-Acute Toxicity Monitoring (Monthly) [Parameter code TAA6C] permit
condition does not include the IWC. I have been using the approved version from the special conditions
library. It appears this is the only one that does not include IWC. This particular condition has been
written that way for as long as I remember using it. It may be worth revising it.
https://outlook.office365.com/mail/id/AAQkADdhYTVmZDBILTE5ZDctNG15MC04ZjliLWU4MjVhZTBhMmJkMgAQAMEcUzOCF9ZEgv2Vgxw%2FM41%... 6/9

10/6/22, 11:25 PM Mail-Denard, Derek-Outlook
It would probably be a good idea to take this up with Kent Wiggins and work with him to update it in the
Conditions Library. If the condition is updated in the library, please let me know so I can update the
permits that I have in draft. I currently have about three in draft that I am using this condition for.
Thanks,
Derek C. Denard
Environmental Program Consultant
N.C. Division of Water Resources
N.C. Department of Environmental Quality
919 707 3618 office
919 707 9000 main DWR
[e-mail]
Water Quality Permitting Section - NPDES
1617 Mail Service Center
Raleigh, NC 27699-1617
Email correspondence to and from this address is subject to the
North Carolina Public Records Law and may be disclosed to third parties.
From:Thomas,Zachary T<[e-mail]>
Sent:Tuesday,August 9, 2022 9:19 AM
To: Denard, Derek<[e-mail]>
Cc: Moore, Cindy<[e-mail]>
Subject: RE: Draft NPDES Permit NCO090077- Irwin Creek Tributary to Remount Road Project
Hi Derek,
Everything for tox looks good. ATB would like to suggest adding the IWC to the toxicity section so that the facility
and the lab will have a point of reference to go off of when making the 5 dilutions for the monthly tests (i.e if IWC
is 90%,they will do dilutions out from that number, etc.).
Please let us know if you have any questions.
Thank you,
Zach Thomas
Environmental Specialist II
Aquatic Toxicology Branch, Compliance and Enforcement
NCDEQ—Division of Water Resources—Water Sciences Section
Based on the current guidance to minimize the spread of COVID-19,the Department of Environmental Quality has
adjusted operations to protect the health and safety of the staff and public. Many employees are working
remotely or are on staggered shifts.To accommodate these staffing changes, all DEQ office locations are limiting
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10/6/22, 11:25 PM Mail-Denard, Derek-Outlook
public access to appointments only. Please check with the appropriate staff before visiting our offices, as we may
be able to handle your requests by phone or email. We appreciate your patience as we continue to serve the
public during this challenging time.
919.743.8441 **New Office Number**
919.743.8517 Fax
[e-mail]
1621 Mail Service Center
Raleigh, NC 27699-1621
Submit ATForms electronically to:[e-mail]
D-EQ'-�)'
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Email correspondence to and from this address is subject to the North Carolina Public Records Law
and may be disclosed to third parties.
From: Denard, Derek<[e-mail]>
Sent: Monday,August 8, 2022 11:44 AM
To: [e-mail]; [e-mail]
Cc: Basinger, Corey<[e-mail]>; Pitner,Andrew<and rew.pitnerCcD ncdenr.gov>; Bell, Wes
<[e-mail]>; Watson, Edward M <[e-mail]>;Thomas, Zachary T
<[e-mail]>; Kinney, Maureen <[e-mail]>; Farmer, Richard L
<[e-mail]>
Subject: Draft NPDES Permit NCO090077- Irwin Creek Tributary to Remount Road Project
Dear Mr. McClanahan:
In order to provide more convenience, control, and security to our permittees and assist them in
processing their transactions, the Division of Water Resources is currently transitioning towards
electronic correspondence. This will hopefully provide more efficient service to our permittees and
other partners and will allow us to more effectively process and track documents. We are writing to ask
you for your approval of the transmittal of documents related to your permitting and related activities
with the Division in an electronic format. Documents will be emailed to the appropriate contact
person(s) in your organization in a PDF format.
Please respond to me through email with verification that transmittal of your documents in an
electronic manner is acceptable to you. Please respond to this email confirming that you received the
attached document(s), were able to open and view the document(s) and have saved/printed a copy for
your records.
If you have any questions, please feel free to contact me.
Sincerely,
Derek C. Denard
Environmental Program Consultant
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10/6/22, 11:25 PM Mail-Denard, Derek-Outlook
N.C. Division of Water Resources
N.C. Department of Environmental Quality
919 707 3618 office
919 707 9000 main DWR
[e-mail]
Water Quality Permitting Section - NPDES
1617 Mail Service Center
Raleigh, NC 27699-1617
Email correspondence to and from this address is subject to the
North Carolina Public Records Law and may be disclosed to third parties.
https://outlook.office365.com/mail/id/AAQkADdhYTVmZDBILTE5ZDctNG15MC04ZjliLWU4MjVhZTBhMmJkMgAQAMEcUzOCF9ZEgv2Vgxw%2FM41%... 9/9

10/6/22, 11:29 PM Mail-Denard, Derek-Outlook
[External] RE: [EXT]Draft NPDES Permit NCO090077 - Irwin Creek Tributary to Remount
Road Project
McClanahan, Jeffrey <[e-mail]>
Tue 8/9/2022 11:42 AM
To: Denard, Derek <[e-mail]>;[e-mail] <[e-mail]>
Cc: Basinger, Corey <[e-mail]>;Pitner, Andrew <[e-mail]>;Bell, Wes
<[e-mail]>;Watson, Edward M <[e-mail]>;Thomas, Zachary T
<[e-mail]>;Kinney, Maureen <[e-mail]>;Farmer, Richard L
<[e-mail]>
CAUTION: External email. Do not click links or open attachments unless you verify.Send all suspicious email as an attachment
to Report Spam.
Hi Derek,
Yes, electronic is acceptable!
Thanks,
Mac McClanahan / Engineering Project Manager
CHARLOTTE WATER
5100 Brookshire Blvd. / Charlotte, NC 28216
C: 704-995-7489/charlottewater.org
From: Denard, Derek<[e-mail]>
Sent: Monday,August 8, 2022 11:44 AM
To: McClanahan,Jeffrey<[e-mail]>; [e-mail]
Cc: Basinger, Corey<[e-mail]>; Pitner, Andrew<[e-mail]>; Bell,Wes
<[e-mail]>; Watson, Edward M <[e-mail]>;Thomas, Zachary T
<[e-mail]>; Kinney, Maureen <[e-mail]>; Farmer, Richard L
<[e-mail]>
Subject: [EXT]Draft NPDES Permit NCO090077- Irwin Creek Tributary to Remount Road Project
Dear Mr. McClanahan:
In order to provide more convenience, control, and security to our permittees and assist them in
processing their transactions, the Division of Water Resources is currently transitioning towards
electronic correspondence. This will hopefully provide more efficient service to our permittees and
other partners and will allow us to more effectively process and track documents. We are writing to ask
you for your approval of the transmittal of documents related to your permitting and related activities
with the Division in an electronic format. Documents will be emailed to the appropriate contact
person(s) in your organization in a PDF format.
Please respond to me through email with verification that transmittal of your documents in an
electronic manner is acceptable to you. Please respond to this email confirming that you received the
attached document(s), were able to open and view the document(s) and have saved/printed a copy for
your records.
https://outlook.office365.com/mail/id/AAQkADdhYTVmZDBILTE5ZDctNGI5MC04ZjliLWU4MjVhZTBhMmJkMgAQAMEcUzOCF9ZEgv2Vgxw%2FM41%... 1/2

10/6/22, 11:29 PM Mail-Denard, Derek-Outlook
If you have any questions, please feel free to contact me.
Sincerely,
Derek C. Denard
Environmental Program Consultant
N.C. Division of Water Resources
N.C. Department of Environmental Quality
919 707 3618 office
919 707 9000 main DWR
[e-mail]
Water Quality Permitting Section - NPDES
1617 Mail Service Center
Raleigh, NC 27699-1617
Email correspondence to and from this address is subject to the
North Carolina Public Records Law and may be disclosed to third parties.
https://outlook.office365.com/mail/id/AAQkADdhYTVmZDBILTE5ZDctNG15MC04ZjliLWU4MjVhZTBhMmJkMgAQAMEcUzOCF9ZEgv2Vgxw%2FM41%... 2/2