NC0024970_Fact Sheet_20231027

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Fact Sheet
NPDES Permit No. NC0024970

Permit Writer/Email Contact: Nick Coco, [e-mail]
Date: October 18, 2023
Division/Branch: NC Division of Water Resources/NPDES Municipal Permitting
Fact Sheet Template: Version 09Jan2017

Permitting Action:
☒ Renewal
☐ Renewal with Expansion
☐ New Discharge
☐ Modification (Fact Sheet should be tailored to mod request)

Note: A complete application should include the following:
• For New Dischargers, EPA Form 2A or 2D requirements, Engineering Alternatives Analysis, Fee
• For Existing Dischargers (POTW), EPA Form 2A, 3 effluent pollutant scans, 4 2nd species WET
tests.
• For Existing Dischargers (Non-POTW), EPA Form 2C with correct analytical requirements based
on industry category.

Complete applicable sections below. If not applicable, enter NA.

1. Basic Facility Information

Facility Information
Applicant/Facility Name: Charlotte Water/McAlpine Creek Wastewater Management Facility
(WWMF)
Applicant Address: 5100 Brookshire Blvd., Charlotte, NC 28216
Facility Address: 12701 Lancaster Highway, Pineville, NC 28134
Permitted Flow: 64.0 MGD
Facility Type/Waste: MAJOR Municipal; 90% domestic, 10% industrial*
Facility Class: Grade IV Biological Water Pollution Control System
Treatment Units: Flow equalization, screening, grit removal, primary clarifiers, aeration
basins, secondary clarifiers, biological and chemical phosphorus
removal, alkaline addition for nitrification, chlorination, dichlorination,
anaerobic sludge digestion, centrifuges and gravity sludge thickeners,
rapid sand filters
Pretreatment Program (Y/N) Y, LTMP
County: Mecklenburg
Region Mooresville
*Based on permitted flows.

Briefly describe the proposed permitting action and facility background: Charlotte Water has applied for
an NPDES permit renewal at 64.0 MGD for the McAlpine Creek WWMF. This facility serves a
population of approximately 574,100 residents, as well as 17 significant industrial users (SIUs), including
6 categorical industrial users (CIUs), via an approved pretreatment program. Treated domestic and
industrial wastewater is discharged via Outfall 001 into McAlpine Creek, a class C waterbody in the

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Catawba River Basin. Outfall 001 is located approximately 2.0 miles upstream of the North Carolina-
South Carolina border.

Additionally, Charlotte Water is scheduling improvements to the facility, including an upgrade to the
headworks to fine barscreen and grit pump/vortex grit classifier, an upgrade to their SCADA system, and
an upgrade from coarse bubble diffused air to fine bubble diffused air. The reliability and process
improvements were anticipated to be completed in early 2023. Authorization to Construct permits
024970A15 and 024970A16 were issued in February 2023 and October 2023 for various improvements at
the McAlpine Creek WWMF; biosolids treatment facilities rehabilitation is projected to complete
construction by the end of 2024; and preliminary and primary treatment facilities improvements are
expected to be completed shortly thereafter in early 2025.

Sludge disposal: Biosolids residuals are permitted, managed, and disposed under a contract with Synagro.
Land application and land filling are the means for ultimate use of the residuals. This is managed under
permit WQ0000057.

Inflow and Infiltration (I/I): Charlotte Water estimates approximately 4.176 MGD of I/I is experienced at
the McAlpine Creek WWMF. Charlotte Water provided a robust collection system maintenance plan that
is currently being followed to minimize I/I experienced throughout their system, which includes manhole
inspections, smoke testing, CCTV, flow monitoring and pipe rehabilitation/replacement.

2. Receiving Waterbody Information:
Receiving Waterbody Information
Outfalls/Receiving Stream(s): Outfall 001 – McAlpine Creek
Stream Segment: 11-137-9
Stream Classification: C
Drainage Area (mi2): 92.4
Summer 7Q10 (cfs) 2
Winter 7Q10 (cfs): 10
30Q2 (cfs): 13.5
Average Flow (cfs): 62.4
IWC (% effluent): 98%
2022 303(d) listed/parameter: Yes; listed as exceeding criteria for benthos and fish
community
Subject to TMDL/parameter: Yes- State wide Mercury TMDL implementation; Fecal
coliform TMDL for McAlpine Creek (DM 1000/100 ml); SC
DHEC ongoing development on nutrient TMDL in the
Catawba basin*
Basin/Sub-basin/HUC: Catawba River/03-08-34/HUC: 0305010301
USGS Topo Quad: G15SE
*Please see attached for the 2020 SCDHEC Lower Catawba River Basin – 2020 Nutrient Study.

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3. Effluent Data Summary
Effluent data for Outfall 001 is summarized below for the period of January 2018 through August 2022.
Table 1. Effluent Data Summary Outfall 001
Parameter Units Average Max Min Permit Limit
Flow MGD 46.2 104.9 28.3 MA 64.0
CBOD summer mg/l 2.1 5.3 < 2 WA 6.0
MA 4.0
CBOD winter mg/l 2.1 3.9 < 2 WA 12.0
MA 8.0
NH3N summer mg/l 0.1 0.4 < 0.1 WA 3.0
MA 1.0
NH3N winter mg/l 0.1 10 < 0.1 WA 5.7
MA 1.9
TSS mg/l 2.6 11.7 2.5 WA 22.5
MA 15.0
pH SU 7.0 7.6 6.4 6.0 ≥ pH ≤ 9.0
Fecal coliform #/100 ml 7.1 403 < 1
(geometric)
WA 400
MA 200
DM 1000
DO mg/l 8.8 10.1 7.2 DA ≥6.0
TRC µg/l < 15 < 15 < 15
DM 28.0
WA 17.0
(< 50
compliance)
Conductivity umhos/cm 593.7 739 387 Monitor &
Report
Temperature ° C 21.6 27.2 15.3 Monitor &
Report
TN mg/l 19.8 28.1 9.4 Monitor &
Report
TP mg/l 0.4 0.92 0.16 Monitor &
Report
TP Load lbs/day 163.1 311.18 100.05 1067
TP Load* lbs/day 451.7 656.31 288.68 826.0
Total Silver ug/l < 1 < 1 < 1 Monitor &
Report
Total Phenolic
Compounds ug/l 50.6 70 < 50 Monitor &
Report
Dichlorobromomethane ug/l 6.1 10.1 3.2 Monitor &
Report
Total Hardness mg/l 152.5 180 120 Monitor &
Report
MA-Monthly Average, WA-Weekly Average, DM-Daily Maximum, DA=Daily Average
* annual rolling average of combined discharge of 3 WWTPs: Sugar Creek WWTP, Irwin Creek WWTP, and
McAlpine Creek WWTP

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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/l 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: The current permit requires instream monitoring for several locations: Irwin Creek,
McAlpine Creek, Sugar Creek, and Little Sugar Creek. All of these receiving streams are a part of the
facility and facility owner’s (Charlotte Water) instream monitoring program for Sugar Creek WWTP,
Irwin Creek WWTP, and McAlpine WWMF.
For the McAlpine Creek WWMF renewal, instream data for MC1 (upstream) and MC2 (downstream)
were analyzed for the period of January 2018 through August 2022 (see stream map attached in factsheet
attachments for locations of MC1 and MC2). Instream monitoring at the McAlpine Creek stations, MC1
upstream of McAlpine Creek WWMF and MC2 downstream of McAlpine Creek WWMF is required for
dissolved oxygen, temperature, conductivity, and total copper. Total hardness monitoring is also required
upstream at MC1 on a quarterly basis. The data has been summarized in Table 2 below.
Table 2. Instream Monitoring Data Summary McAlpine Creek
Parameter Units Upstream Downstream
Average Max Min Average Max Min
Temperature ° C 20.3 27.1 3.7 22.2 27.3 10
DO mg/l 6.9 12 4.9 7.5 10.5 5.6
Conductivity µmhos/cm 198.7 320 84 472.9 653 101
Total Copper mg/l 2.6 11 2 3.8 18 2.3
Total hardness mg/l 80.7 120 23 - - -
Students t-tests were run at a 95% confidence interval to analyze relationships between instream
samples. A statistically significant difference is determined when the t-test p-value result is < 0.05
Temperature is a parameter of concern for aquatic life. Downstream temperature was not greater than 29
degrees Celsius [per 15A NCAC 02B .0211 (18)] during the period reviewed. Downstream temperature
was greater than upstream temperature by more than 2.8 degrees Celsius on 31 occasions during the
period reviewed. Review of concurrent effluent temperature for these 31 occasions demonstrated a
consistent relationship between elevated effluent temperatures and elevated downstream temperature.
Additionally, it was concluded that a statistically significant difference exists between upstream and
downstream temperature. Effluent temperature does appear to have the potential to influence instream
temperature. Instream temperature monitoring has been maintained and will continue to be tracked for
effluent impact.
Dissolved oxygen is a parameter of concern for aquatic life. Downstream DO did not drop below 5 mg/L
[per 15A NCAC 02B .0211 (6)] during the period reviewed. While it was concluded that a statistically
significant difference exists between upstream and downstream DO, this does not appear to create any
instances of noncompliance with DO standards.
As the facility receives influent flow from several industrial users via an approved pretreatm ent program,
instream conductivity is tracked. It was concluded that a statistically significant difference exists between

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upstream and downstream conductivity with downstream conductivity consistently higher than upstream
conductivity.
It was concluded that a statistically significant difference exists between upstream and downstream
copper with downstream copper concentrations consistently higher than upstream copper concentrations.
Upon review of concurrent effluent total copper demonstrating effluent concentrations at levels generally
greater than upstream concentrations, it does appear that the effluent may have an influence on
downstream total copper. However, both upstream and downstream total copper were not observed at
levels greater than the standard of 21.4 ug/L (calculated based on average reported upstream hardness of
80.7 mg/L and EPA Default Partition Coefficient of 0.348) during the period reviewed.
In addition to the instream monitoring requirements in the permit, Charlotte Water conducted sampling at
the two McAlpine Creek stations for pH, TKN, nitrate + nitrite, Orthophosphate, total chromium, total
zinc, fecal coliform and total phosphorous. Data from January 2018 through August 2022 has been
summarized below.
Table 3. Additional Instream Monitoring Data Summary McAlpine Creek
Parameter Units Upstream Downstream
Average Max Min Average Max Min
pH s.u. 7.1 7.5 6.4 7.1 7.4 6.5
Orthophosphate mg/l 0.05 0.05 0.05 0.2 0.65 0.1
Total
Phosphorous mg/l 0.1 0.1 0.1 0.3 0.7 0.2
TKN mg/l 0.5 1 0.3 0.7 2 0.3
NO3+NO2 mg/l 0.4 0.7 0.1 15.5 26 4.7
Fecal Coliform #/100ml (geomean)
569 61000 19 (geomean)
438 36000 45
Total
Chromium µg/l 5.0 6.7 5 5.2 15 5
Total Zinc µg/l 10.7 32 10 18.1 28 12
No changes are proposed to McAlpine Creek instream monitoring requirements. All instream monitoring
for all parameters for Irwin Creek WWTP’s receiving streams, Irwin Creek and Sugar Creek, and Sugar
Creek WWTP’s receiving stream, Little Sugar Creek, will be maintained in McAlpine Creek WWMF’s
permit (NC0024970) along with McAlpine Creek instream monitoring requirements. Please note that,
while no changes have been made to the instream monitoring requirements listed in the permit for Irwin
Creek, Sugar Creep and Little Sugar Creek, instream summaries will be provided for the other receiving
streams in the applicable permit reviews.
Is this facility a member of a Monitoring Coalition with waived instream monitoring (Y/N): NO
Name of Monitoring Coalition: NA
5. Compliance Summary
Summarize the compliance record with permit effluent limits (past 5 years): The facility did not report
any limit violations during the period reviewed.

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Summarize the compliance record with aquatic toxicity test limits and any second species test results
(past 5 years): The facility passed 18 of 18 quarterly chronic toxicity tests, as well as all 4 second species
chronic toxicity tests from March 2018 to June 2022.
Summarize the results from the most recent compliance inspection: The last facility inspection conducted
in February 2022 reported that the facility was compliant.

6. Water Quality-Based Effluent Limitations (WQBELs)
Dilution and Mixing Zones
In accordance with 15A NCAC 2B.0206, the following streamflows are used for dilution considerations
for development of WQBELs: 1Q10 streamflow (acute Aquatic Life); 7Q10 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/l 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: The current permit
limitations for CBOD are based on a 1995 Streeter-Phelps model (Level B) for instream DO protection.
No changes are proposed from the previous permit limits.
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/l (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/l) and capped at 28 ug/l (acute impacts). Due to analytical issues, all TRC values
reported below 50 ug/l are considered compliant with their permit limit.
Describe any proposed changes to ammonia and/or TRC limits for this permit renewal: The current TRC
limits are expressed as a daily maximum of 28 µg/L and a weekly average of 17 µg/L. TRC limits have
been reviewed in the attached WLA. Based on the 15A NCAC 02B .0211(3) TRC standard of 17 µg/L
and accounting for instream wasteload concentration/dilution, a daily maximum limit of 17 µg/L was
calculated. Additionally, while the 2003 Total Residual Chlorine Policy for NPDES permits (attached)
states that “Facilities discharging to streams with a 7Q10 < 0.05 cfs (zero-flow streams) will receive a
limit of 17 µg/L,” it does not state that limit calculations based on the aquatic life standard of 17 µg/L
cannot be applied if they result in a limit of 17 µg/L. As the calculated limit is more stringent than the
current permit limits, a daily maximum limit of 17 µg/L has been proposed.
The current limitations for ammonia are based on protection of aquatic life utilizing an ammonia chronic
criterion of 1.0 mg/l (summer) and 1.8 mg/l (winter). Acute ammonia limits are derived from chronic

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criteria, utilizing a multiplication factor of 3 for Municipals and a multiplication factor of 5 for Non-
Municipals. The ammonia limits have been reviewed in the attached WLA for toxicity and have been
found to be protective. No changes are proposed.
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 ½ detection limit for “less than” values; and 4) streamflows used for dilution
consideration based on 15A NCAC 2B.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 on effluent toxicant data collected between January 2018
and August 2022. 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:
• Effluent Limit with Monitoring. The following parameters will receive a water quality-based
effluent limit (WQBEL) since they demonstrated a reasonable potential to exceed applicable
water quality standards/criteria: None
• Monitoring Only. The following parameters will receive a monitor-only requirement since they
did not demonstrate reasonable potential to exceed applicable water quality standards/criteria,
but the maximum predicted concentration was >50% of the allowable concentration: None
• No Limit or Monitoring: The following parameters will not receive a limit or monitoring, since
they did not demonstrate reasonable potential to exceed applicable water quality
standards/criteria and the maximum predicted concentration was <50% of the allowable
concentration: Total Arsenic, Total Cadmium, Total Phenolic Compounds, Total Chromium,
Total Copper, Total Cyanide, Total Lead, Total Molybdenum, Total Nickel, Total Selenium,
Total Silver, Total Zinc, Dichlorobromomethane
• POTW Effluent Pollutant Scan Review: Three effluent pollutant scans were evaluated for
additional pollutants of concern.
o The following parameter(s) will receive a water quality-based effluent limit (WQBEL)
with monitoring, since as part of a limited data set, two samples exceeded the allowable
discharge concentration: None
o The following parameter(s) will receive a monitor-only requirement, since as part of a
limited data set, one sample exceeded the allowable discharge concentration: None
o The following parameters will not receive a limit or monitoring, since they did not
demonstrate reasonable potential to exceed applicable water quality standards/criteria and
the maximum predicted concentration was <50% of the allowable concentration: Total
Beryllium

If applicable, attach a spreadsheet of the RPA results as well as a copy of the Dissolved Metals
Implementation Fact Sheet for freshwater/saltwater to this Fact Sheet. Include a printout of the RPA
Dissolved to Total Metal Calculator sheet if this is a Municipality with a Pretreatment Program.

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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 s everal
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: This is a Major POTW, and a chronic WET limit at 90%
effluent will continue on a quarterly frequency.
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/l) 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/l) and/or if any individual value exceeds a TBEL
value of 47 ng/l
Table 4. Mercury Effluent Data Summary
2018 2019 2020 2021 2022
# of Samples 11 13 13 13 7
Annual Average Conc. ng/L 1.1 1.4 0.7 0.81 0.66
Maximum Conc., ng/L 3.9 9.8 0.9 1.16 0.93
TBEL, ng/L 47
WQBEL, ng/L 12.2

Describe proposed permit actions based on mercury evaluation: Since no annual average mercury
concentration exceeded the WQBEL, and no individual mercury sample exceeded the TBEL, no mercury
limit is required. Since the facility is > 2.0 MGD and reported quantifiable levels of mercury (> 1 ng/l),
the mercury minimization plan (MMP) condition has been maintained. Charlotte Water submitted their
MMP with their 2022 Pretreatment Annual Report.
Other TMDL/Nutrient Management Strategy Considerations
If applicable, describe any other TMDLs/Nutrient Management Strategies and their implementation
within this permit: A fecal coliform TMDL was established in February 2002 and the permit contains a
1000/100 mL fecal coliform daily maximum. A bubble limit for total phosphorus is included for Irwin
Creek WWTP, Sugar Creek WWTP, and McAlpine Creek WWMF. As stipulated by the 2002 Settlement
Agreement between Charlotte-Mecklenburg Utilities (CMU), the South Carolina Department of Health
and Environmental Control (SC DHEC) and the North Carolina Division of Water Quality (NC -DWQ),
now North Carolina Division of Water Resources, Charlotte Water’s McAlpine Creek WWMF, Sugar
Creek WWTP and Irwin Creek WWTP must comply with a combined 12 month rolling average limit of
826.0 lbs/day as of February 28, 2006.

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Charlotte Water has asked the Division to revise the Sugar, Irwin, and McAlpine Creek permits to
improve the uniformity of their nutrient conditions. As outlined in the 2021 internal Memorandum
“Charlotte Water Permits – Proposed Uniform Nutrient Conditions” (attached), changes are proposed to
the nutrient language and permit conditions for each of these permits to apply more consistent
terminology, units of measure, and parameter codes for the various measures of TP , apply consistent
methods for calculation of TN and TP loads and require reporting of interim calculation results, to make it
easier to see how the final results were derived.
The changes include:
• Section A.(1.): Added Total Monthly Flow (TMF) reporting, created separate rows for TP
concentration and mass, applied new parameter names in the table and footnotes to improve
clarity, provided clearer linkage between the limits page, footnotes, and the other TP special
conditions.
• Special Condition A.(7.): Applied the new parameter names and added linkage to the limits page
and calculations condition.
• Special Condition A.(8.): Applied the new terminology and described the calculations for each
measure of TP used on the limits page. Clarified how the combined TP loads would be calculated
and where they would be reported.
The changes will not affect the TN and TP limits or monitoring requirements for the facilities.
Other WQBEL Considerations
If applicable, describe any other parameters of concern evaluated for WQBELs: The bubble limit for total
phosphorus was analyzed for Irwin Creek WWTP, Sugar Creek WWTP, and McAlpine Creek WWMF.
There were no compliance concerns for the period analyzed (January 2018- August 2022) and the three
facilities stayed below their total phosphorus rolling average bubble limit.
As required by Session Law 2018-5, Senate Bill 99, Section 13.1(r), every applicant shall submit
documentation of any additional pollutants for which there are certified methods with the permit
application if their discharge is anticipated. The list of pollutants may be found in 40 CFR Part 136,
which is incorporated by reference. Charlotte Water informed the Division that “To the best of our
knowledge, all samples collected at McAlpine WWMF that are covered under a method listed in 40 CFR
Part 136 and run by a state certified lab, have been reported to NCDWR on our monthly DMR’s. No
additional pollutants with methods listed in 40 CFR Part 136 have been analyzed, therefore, the Chemical
Addendum form was not submitted in our application.”
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 2H.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)
Municipals (if not applicable, delete and skip to Industrials)
Are concentration limits in the permit at least as stringent as secondary treatment requirements (30 mg/l
CBOD5/TSS for Monthly Average, and 45 mg/l for CBOD5/TSS for Weekly Average). YES
If NO, provide a justification for alternative limitations (e.g., waste stabilization pond). NA
Are 85% removal requirements for CBOD5/TSS included in the permit? YES
If NO, provide a justification (e.g., waste stabilization pond). NA

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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: NA
9. Antibacksliding Review:
Sections 402(o)(2) and 303(d)(4) of the CWA and federal regulations at 40 CFR 122.44(l) 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): NO
If YES, confirm that antibacksliding provisions 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.
Charlotte Water was granted 2/week monitoring for CBOD, ammonia, TSS and fecal coliform based on
2012 DWR Guidance Regarding the Reduction of Monitoring Frequencies in NPDES Permits for
Exceptionally Performing Facilities during their 2017 renewal. Charlotte Water has requested
continuation of this monitoring frequency reduction as part of their renewal application. The last three
years of the facility’s data for these parameters have been reviewed in accordance with the criteria
outlined in the guidance. Based on this review, 2/week monitoring frequency has been maintained for
CBOD, ammonia, TSS and fecal coliform.
To identify PFAS concentrations in waters classified as Water Supply (WS) waters, monitoring
requirements are to be implemented in permits with pretreatment programs that discharge to WS waters.
While there are no WS waters designated by the Division downstream of the discharge, the dis charge
point is upstream of the border between North Carolina and South Carolina. Since all waters in South
Carolina are deemed suitable for drinking water uses with appropriate treatment, and to ensure PFAS
contamination does not cross State lines, and as the McAlpine Creek WWMF has a pretreatment program,
monitoring of PFAS chemicals has been added to the permit. Currently, EPA Method 1633 is in its 4th
draft form and not yet published in the Federal Register as a final methodology. As the McAlpine Creek
WWMF accepts influent wastewater from several industrial facilities that are potential sources of PFAS
via the approved pretreatment program, and since an EPA method for sampling and analyzing PFAS in

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wastewater is not currently available, influent and post-filtration PFAS monitoring has been added to the
permit at a quarterly frequency using the Draft Method 1633. Upon evaluation of laboratory availability
and capability to perform the draft analytical method, it was determined that the sampling may be
conducted using the 3rd draft method 1633 or more recent. Sampling using the draft method shall take
effect the first full calendar quarter following 6 months after the effective date of the permit to provide
Charlotte Water time to select a laboratory, develop a contract, and begin collecting samples. Effective 6
months after EPA has a final wastewater method in 40 CFR136 published in the Federal Register,
Charlotte Water shall conduct effluent monitoring using the Final Method 1633 and is no longer required
to conduct influent and post-filtration monitoring.
In addition to monitoring at the wastewater management facility, Charlotte Water shall identify and
monitor SIUs suspected of discharging PFAS compounds within 6 months of the permit effective date.
Charlotte Water shall update their Industrial Waste Survey- (IWS) to identify indirect dischargers of
PFAS contributing to concentrations experienced at the McAlpine Creek WWMF. A summary of
information learned during this process will be provided as part of the 2024 Pretreatment Annual Report
(PAR). Within 6 months of completion of the IWS, Charlotte Water shall begin sampling of indirect
dischargers identified as potential PFAS sources. Sampling conducted at SIUs and indirect dischargers
shall also be conducted at a quarterly frequency. This is a summary of the PFAS requirements. For a
detailed outline of the specific PFAS requirements, see Special Condition A.(10.) PFAS Monitoring
Requirements.
As the McAlpine Creek WWMF accepts influent wastewater from several industrial facilities that are
potential sources of 1,4-dioxane via the approved pretreatment program, as no additional sampling has
been conducted for 1,4-dioxane at this facility as identified in the chemical addendum submitted by
Charlotte Water, and as the facility discharges above the NC/SC state border line, monthly effluent
monitoring for 1,4-dioxane as well as a 1,4-dioxane reopener condition have been added to the permit.
After a 24-month sampling period, the Permittee may request the Division conduct a review of submitted
data for assessment and approval of a 1,4-dioxane monitoring frequency reduction from monthly to
quarterly.
The statement, “There shall be no discharge of floating solids or visible foam in other than trace
amounts,” was removed during the 2017 renewal. This statement has been standard language in NPDES
permits since the program’s inception and is still used widely by state and federal permitting authorities.
Because it is subjective, it is hardly suitable as the basis for an enforcement action; instead, we would rely
on the permittee’s monitoring reports to establish and quantify any limits exceedances. Part of its value is
that it provides a quick measure of effluent quality and possible water quality impacts. A DWR inspector
who notices such an issue at a discharge can address the matter while on site rather than waiting days or
weeks for effluent monitoring to be reported. In addition, there is also a concern of the presence of
emerging contaminants in visible foams. Therefore, this condition should be maintained in NPDES
permits. As such, the statement has been added back into the permit in Section A.(1.).

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. While NPDES regulated facilities would initially be required to submit additional
NPDES reports electronically effective December 21, 2020, EPA extended this deadline from December
21, 2020, to December 21, 2025. The current compliance date, effective January 4, 2021, was extended as
a final regulation change published in the November 2, 2020 Federal Register. This permit contains the
requirements for electronic reporting, consistent with Federal requirements.

Page 12 of 16

12.Summary of Proposed Permitting Actions:
Table 5. Current Permit Conditions and Proposed Changes Outfall 001
Parameter Current Permit Proposed Change Basis for Condition/Change
Flow MA 64.0 MGD No change 15A NCAC 2B .0505
CBOD5 Summer:
MA 4.0 mg/l
WA 6.0 mg/l
Winter:
MA 8.0 mg/l
WA 12.0 mg/l
Monitor and report 2/Week
No change WQBEL. 1995 Level B model,
Surface Water Monitoring, 2012
DWR Guidance Regarding the
Reduction of Monitoring
Frequencies in NPDES Permits for
Exceptionally Performing Facilities
NH3-N Summer:
MA 1.0 mg/l
WA 3.0 mg/l
Winter:
MA 1.9 mg/l
WA 5.7 mg/l
Monitor and report 2/Week
No change WQBEL. 2022 WLA review;
Surface Water Monitoring, 2012
DWR Guidance Regarding the
Reduction of Monitoring
Frequencies in NPDES Permits for
Exceptionally Performing Facilities
TSS MA 15.0 mg/l
WA 22.5 mg/l
Monitor and report 2/Week
No change WQBEL. 1995 Level B model,
Surface Water Monitoring, 2012
DWR Guidance Regarding the
Reduction of Monitoring
Frequencies in NPDES Permits for
Exceptionally Performing Facilities
Fecal coliform MA 200 /100ml
WA 400 /100ml
DM 1000/100ml
Monitor and report 2/Week
No change WQBEL. State WQ standard, 15A
NCAC 2B .0200; 2002 TMDL for
fecal, results in DM; Surface Water
Monitoring, 2012 DWR Guidance
Regarding the Reduction of
Monitoring Frequencies in NPDES
Permits for Exceptionally
Performing Facilities
DO > 6 mg/l
Monitor and report Daily
No change WQBEL. 1995 Level B model;
Surface Water Monitoring, 15A
NCAC 2B. 0500
pH 6 – 9 SU
Monitor and report Daily
No change WQBEL. State WQ standard, 15A
NCAC 2B .0200; Surface Water
Monitoring, 15A NCAC 2B. 0500
Conductivity Monitor and report Daily No change Surface Water Monitoring, 15A
NCAC 2B. 0500
Temperature Monitor and report Daily No change Surface Water Monitoring, 15A
NCAC 2B. 0500
Total Residual
Chlorine
WA 17 ug/L
DM 28 ug/L
Monitor and report Daily
DM 17 ug/L
Monitor and report
Daily
WQBEL. 2022 WLA review and
Surface Water Monitoring, 15A
NCAC 2B. 0500
Total Nitrogen Monitor and report Monthly No change

Surface Water Monitoring, 15A
NCAC 2B. 0500

Page 13 of 16

TKN No requirement Monitor and report
Monthly
For calculation of Total Nitrogen
NO3+NO2 No requirement Monitor and report
Monthly
For calculation of Total Nitrogen
Total
Phosphorus
826.0 lbs/day bubble limit for
Irwin Creek WWTP, Sugar
Creek WWTP, and McAlpine
Creek WWTP
MA 1,067lbs/day
Monitor and report Monthly
No change WQBEL. Required TP nutrient
limits per 2002 permitting strategy
agreement with Charlotte-
Mecklenburg Utilities (CMU), the
South Carolina Department of
Health and Environmental Control
(SC DHEC) and the North Carolina
Division of Water Quality (NC-
DWQ); Surface Water Monitoring,
15A NCAC 2B. 0500
Total Hardness Quarterly monitoring
Upstream and in Effluent
No change Hardness-dependent dissolved
metals water quality standards
approved in 2016
Total Silver Monitor and report Quarterly Remove
requirement
Based on results of RPA; All values
non-detect < 1 ug/L - no monitoring
required
Dichlorobromo-
methane
Monitor and report Quarterly Remove
requirement
Based on results of RPA; No RP,
Predicted Max < 50% of Allowable
Cw - No Monitoring required
Total Phenolic
Compounds Monitor and report Quarterly Remove
requirement
Based on results of RPA; No RP,
Predicted Max < 50% of Allowable
Cw - No Monitoring required
1,4-dioxane No requirement
Monitor and Report
Monthly and
reopener condition;
24-month sampling
reassessment
Based on PT Program – industrial
facilities linked to 1,4-dioxane
PFAS No requirement
See Special
Condition A.(10.)
PFAS Monitoring
Requirements
Evaluation of PFAS contribution:
pretreatment facility; Discharge
above NC/SC border
Toxicity Test Chronic limit, 90% effluent

No change WQBEL. No toxics in toxic
amounts. 15A NCAC 2B.0200 and
15A NCAC 2B.0500
Effluent
Pollutant Scan
Three times per permit cycle No change;
conducted in 2025,
2026, 2027
40 CFR 122
Mercury
Minimization
Plan (MMP)
MMP Special Condition No change; revise
wording towards its
maintenance
WQBEL. Consistent with 2012
Statewide Mercury TMDL
Implementation.
Electronic
Reporting
Electronic Reporting Special
Condition
No change In accordance with EPA Electronic
Reporting Rule 2015.
MGD – Million gallons per day, MA - Monthly Average, WA – Weekly Average, DM – Daily Max

Page 14 of 16

13. Public Notice Schedule:
Permit to Public Notice: 05/16/2023

Per 15A NCAC 2H .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. NPDES Division Contact
If you have any questions regarding any of the above information or on the attached permit, please
contact Nick Coco at [phone] or via email at [e-mail].

15. Fact Sheet Addendum (if applicable):
The draft was submitted to Charlotte Water, EPA Region IV, South Carolina DHEC, and the Division’s
Mooresville Regional Office, Aquatic Toxicology Branch, Operator Certification Program and
Pretreatment Unit for review.

Charlotte Water provided comment to the Division on May 24, 2023. A summary of comments and
Division responses is provided below:

1. Comment: Please correct the permit number referenced in A.(3.)(c.) for Irwin Creek WWTP to
NC0024945.

Response: The permit number has been corrected.

2. Comment: Please correct the permit number referenced in A.(4.)(c.) Irwin Creek WWTP to
NC0024945.

Response: The permit number has been corrected and the language has been revised to identify
Sugar Creek as the downstream sampling stream for the Irwin Creek WWTP.

3. Comment: Charlotte Water requests the statement “There shall be no discharge of floating solids
or visible foam in other than trace amounts” be removed from Part A.(1.)(b.) of the permit.

Response: The statement, “There shall be no discharge of floating solids or visible foam in other
than trace amounts,” has been standard language in NPDES permits since the program’s inception
and is still used widely by state and federal permitting authorities. Part of its value is that it
provides a quick measure of effluent quality and possible water quality impacts. A DWR
inspector who notices such an issue at a discharge can address the matter while on site rather than
waiting days or weeks for effluent monitoring to be reported. In addition, there is also a concern
of the presence of emerging contaminants in visible foams. Therefore, the statement has been
maintained.

4. Comment: Charlotte Water requests the 1,4-Dioxane monitoring requirement to be set at monthly
for a period of 12 months then quarterly thereafter.

Response: Due to the size and complexity of the discharge, and the proximity of the discharge to
the SC border, the footnote has been maintained at 24 months. However, please note, permittees

Page 15 of 16

may choose to request permit modification and a reasonable potential analysis be conducted after
12 monthly samples are collected, and the modified permit would be subject to public comment.

5. Comment: Charlotte Water requests the quarterly monitoring for PFAS be reduced to
semiannually.

Response: Due to the size and complexity of the discharge, and the proximity of the discharge to
the SC border, quarterly PFAS monitoring has been maintained. Please reference Monitoring
Requirements above and Special Condition A.(10.) of the permit for additional information
regarding revisions to the PFAS requirements.

6. Comment: Charlotte Water requests that the greater than or equal to (≥) and less than or equal to
(≤) symbols that are used in the fact sheet be mirrored in Part A.(1.)(a) either in the table or in a
footnote.

Response: The Division considers “Between 6.0 and 9.0 standard units” to be greater than or
equal to (≥) 6.0 standard units and less than or equal to (≤) 9.0 standard units for compliance
purposes. While the permit has not been revised to reflect this for the sake of consistency with the
rest of the NPDES permits, a note has been included in the final cover letter indicating this
interpretation and practice per Permittee request.

The Southern Environmental Law Center (SELC) provided comment to the Division on June 15, 2023
requesting implementation of more restrictive requirements regarding 1,4-dioxane and PFAS, including
increased monitoring and permit limitations for both as well as require pretreatment actions. As no data
were available for 1,4-dioxane or PFAS, sampling has been required at a monthly and quarterly frequency
for each respective parameter(s). Additionally, a reopener condition has been incorporated into the permit
for 1,4-dioxane and the Division may reopen the permit upon receipt of sufficient data to demonstrate
cause for concern. The monitoring requirements have been maintained for both PFAS and 1,4-dioxane.

However, out of the concerns raised and the continual industrial growth of the area, the PFAS monitoring
requirement has been revised. Please reference Monitoring Requirements above and Special Condition
A.(10.) of the permit for additional information regarding the revisions.

Were there any changes made since the Draft Permit was public noticed (Yes/No): Yes
If Yes, list changes and their basis below:
• Special Condition A.(3.)(c.) has been revised to indicate the appropriate NPDES permit number
for the Irwin Creek WWTP.
• Special Condition A.(4.)(c.) has been revised for clarity and to indicate the appropriate NPDES
permit number for the Irwin Creek WWTP.
• To assess the industrial contribution of PFAS to the McAlpine Creek WWMF and assess levels of
PFAS compounds in the facility effluent, Special Condition A.(10.) has been revised.

16. Fact Sheet Attachments (if applicable):
• RPA Spreadsheet Summary
• NPDES Implementation of Instream Dissolved Metals Standards – Freshwater Standards
• NH3/TRC WLA Calculations
• BOD & TSS Removal Rate Calculations
• Mercury TMDL Calculations
• WET Testing and Self-Monitoring Summary

Page 16 of 16

• Compliance Inspection Report
• 2003 TRC Policy
• 2021 Internal Memo Charlotte Water Permits – Proposed Uniform Nutrient Conditions
• Requested Additional Information
• Email Correspondence
• Public Comments
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Fresno Bee Miami Herald Sun Herald-Biloxi
AFFIDAVIT OF PUBLICATION
Account# Order Number Identification Order PO Amount Cols Depth
28386 421488 Print Legal Ad-IPL01228700-IPL0122870 626.56 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
[e-mail]
oaths affirmations,etc.,personally appeared,
being duly sworn or affirmed according to law,
Public Notice doth depose and say that he/she is a
North Carolina Environmental Management Commission/NPDES Unit representative of The Charlotte Observer 1
1617 Mail Service Center
Raleigh.NC 2 7699-1 61 7 Publishing Company,a corporation organized and j
Notice of Intent to Issue a NPDES Wastewater Permit NC0024970 McAlipine doing business under the laws of the State ofCreekWWTP
Delaware,and publishing a newspaper known as
The North Carolina Environmental Management Commission proposes to issue
a NPDES wastewater discharge permit to the person(s) listed below. Written The Charlotte Observer in the city of Charlotte,
comments regarding the proposed permit will be accepted until 30 days atterthe County of Mecklenburg,and State of Northpublishdateofthisnotice.The Director of the NC Division of Water Resources
DWR)may hold a public hearing should there be a significant degree of pub- Carolina and that as such he/she is familiar with
lie interest.Please mail comments and/or information requests to DWR at the I
above address.Interested persons may visit the DWR at 512 N.Salisbury Street, the books,records,files,and business of said 1
Raleigh.NC 27604 to review the information on file. Additional information on Corporation and by reference to the files of saidNPDESpermitsandthisnoticemaybefoundonourwebsite:https:/!deq.nc.gov/
public-notices-hearings.or by calling [phone]. Charlotte Water (5100 publication,the attached advertisement was
Brookshire Boulevard,Charlotte,NC 282161 has requested renewal of NPDES
permit NC0024970 for its McAlpine Creek Wastewater Management Facility,lo- inserted.The following is correctly copied from
cated in Mecklenburg County.This permitted facility discharges treated munici- the books and files of the aforesaid Corporation
pal and industrial wastewater to McAlpine Creek.a class C water in the Catawba
River Basin.Currently,CBOD.ammonia.TSS,fecal conform.dissolved oxygen. and Publication.
pH.total residual chlorine and total phosphorous are water quality limited.This
discharge may affect future allocations in this segment of McAlpine Creek.
IPL0122870 1 insertion(s)published on:
May 16 2023 05/16/23
1
CX71Ci'--RfMITOPCICejZfril i
In Testimony Whereof I have hereunto set my hand
and affixed my seal on the 19th day of May,2023
S tC1 '4''•4,?41 C•Q(Ate-
Notary Public in and for the state of Texas,residing in
Dallas County
r-
STEPHANIE HATCHER
My Notary IU#133534406
7. Expires January 14,2026
Extra charge for lost or duplicate affidavits.
Legal document please do not destroy!

May 24, 2023
Mr. Nick Coco, PE
NCDEQ – Department of Water Resources
NPDES Municipal Permitting Unit
1612 Mail Service Center
Raleigh, NC 27699-1612

Subject: Charlotte Water Comments – Draft NPDES Permit Renewal for McAlpine Creek WWMF (Permit
NC0024970)

Mr. Coco:

Charlotte Water (CLTWater) has reviewed the Draft Permit for McAlpine Creek WWMF’s NPDES Permit
Renewal (Permit NC0024970) and is submitting the following comments and requests for your
consideration. We have underlined our specific requests throughout the document for easy reference.

 Part A.(3.)(c.) lists Sugar Creek WWTP’s permit number (NC0024937) in reference to Irwin Creek
WWTP. Please update the permit number to NC0024945.

 Part A.(4.)(c.) lists Irwin Creek WWTP in reference to Sugar Creek WWTP’s permit number and
receiving stream. Please update the WWTP name to Irwin Creek WWTP.

 CLTWater requests the statement “There shall be no discharge of floating solids or visible foam
in other than trace amounts” be removed from Part A.(1.)(b.) of the permit. The removal of this
statement from McAlpine Creek WWMF’s pervious permit renewal was not made in error. It
was specifically omitted from the permit at CLTWater’s request because it is vague and open to
interpretation. DEQ granted CLTWater’s request and left it out of the permit. As stated in the
draft fact sheet, this language is “subjective and hardly suitable for the basis for an enforcement
action”. Due to its subjective nature, this statement should be removed from the permit.

The draft fact sheet also states that “A DWR inspector who notices such an issue at a discharge
can address the matter while on site rather than waiting days or weeks for effluent monitoring
to be reported.” The idea that this narrative limitation is “hardly suitable for the basis of an
enforcement action”, yet an inspector “can address the matter while onsite” is contradictory. A
DWR inspector who notices any such issues at a discharge would be sufficiently capable of
addressing the matter on site without the facility being in jeopardy of violating a subjective
permit condition. Further, this statement being included in our permit could easily be
misconstrued by 3rd parties, placing unnecessary risk on CLTWater and NCDEQ if a 3rd party were
to allege that a violation of the permit was occurring due to this condition. As this condition is
ambiguous, unenforceable, and open to interpretation, CLTWater believes this statement
should not be included in any NPDES permits.
 CLTWater is in agreement with DEQ that it is necessary to assess potential contributions of 1,4-
Dioxane to our wastewater treatment facilities from industrial users. CLTWater’s Pretreatment
program has recently begun assessments of potential contributions of all SIUs and within the
collection system. In conjunction with the SIU sampling, CLTW feels that monthly sampling for
12 months followed by quarterly monitoring is sufficient to evaluate and assess whether there
are industrial contributions of 1,4-Dioxane. DEQ has informed CLTWater that it has identified at
least one industry type with the potential to discharge 1,4 Dioxane at each of the McAlpine,
Irwin, and Sugar facilities. Therefore, CLTWater expects this monitoring requirement to be
included in each of our facilities’ permits. When considered collectively, CLTWater feels that
monthly sampling for 24 months would be costly, superfluous, and overly burdensome.
CLTWater requests the 1,4-Dioxane monitoring requirement to be set at monthly for a period of
12 months then quarterly thereafter.

 CLTWater is aware of at least one other permit in the State that discharges to a drinking water
supply categorized as WS-V, that monitors for PFAS semiannually. McAlpine Creek WWMF,
while a larger facility, discharges to Class-C recreational waterways and is being required to do
so quarterly. CLTWater believes that water bodies in the State, when categorized, are done so
consistently and appropriately, regardless of the proximity to State boundaries. As such,
CLTWater believes that NPDES permittees should be afforded the same consistent and
appropriate discharge limitations and monitoring requirements reflective of the receiving water
classification.

CLTWater is aware that PFAS monitoring will likely be a requirement for several other CLTWater
NPDES permits. Having several facilities impacted by this, quarterly monitoring would be
expensive and burdensome. Semiannual sampling would be less burdensome when taking into
account all 6 CLTWater facilities. Additionally, CLTWater has significant concerns regarding
laboratory capacity. Due to the current volume of PFAS samples being delivered to local NC
labs, the turnaround time is running 30-45 days making it difficult to ensure compliance with
reporting requirements. Expedited turnaround times can be requested, if available, but will
result in additional costs. Laboratories themselves have expressed concern to CLTWater that
they would be unable to fulfill our sampling and analytical needs. Due to supply shortages at
subcontract labs, CLTWater has recently experienced challenges obtaining the requested
number of PFAS-free sampling containers necessary to sample at our facilities and SIUs.
CLTWater requests the quarterly monitoring for PFAS be reduced to semiannually.

 As stated in the permit, it could be perceived that a pH value between 6.0 and 9.0 is not
inclusive of 6.0 and 9.0. CLTWater requests that the greater than or equal to (≥) and less than or
equal to (≤) symbols that are used in the fact sheet are mirrored in the NPDES permit effluent
limitations table. Technically what is written in the permit and what is written in the fact sheet
is inconsistent. CLTWater is unclear as to whether a pH of exactly 6.0 or exactly 9.0 would be
considered compliant based on how it is written in the permit. CLTWater requests a footnote to
be included in Part A.(1.)(a) clarifying this language.

CLTWater appreciates your consideration of our requests and comments. If you have any questions or
require further information concerning our comments, please feel free to contact Shannon Sypolt,
Water Quality Program Administrator, at [phone] or me at [phone].

Respectfully,

Joseph Lockler
Operations Chief, Charlotte Water

CC:
Shannon Sypolt - Water Quality Program Administrator, CLTWater
Maggie Macomber - Engineering Program Manager, CLTWater
Darrell DeWitt – Operations Manager, CLTWater

June 15, 2023
VIA E-MAIL
Nick Coco
NCDEQ/DWR/NPDES
Municipal Permitting Unit
1617 Mail Service Center
Raleigh, NC 27699-1617
[e-mail]

Re: Southern Environmental Law Center Comments on NPDES Wastewater
Draft Permit NC0024970 McAlpine WWTP
Dear Mr. Coco:
The Southern Environmental Law Center offers the following comments on the draft
renewal permit for National Pollutant Discharge Elimination System (“NPDES”) Permit
NC0024970, issued by the North Carolina Department of Environmental Quality (the
“Department”) to Charlotte Water for the McAlpine Wastewater Management Facility
(“McAlpine”).1 McAlpine discharges into McAlpine Creek, a class C water less than 2 miles
upstream of the North Carolina-South Carolina border,2 and approximately 20 river miles
upstream of the drinking water intake for the Catawba River Water Supply Project, which
provides drinking water for thousands of people in Union County, North Carolina and Lancaster
County, South Carolina.3
The draft permit allows McAlpine to discharge wastewater likely contaminated with per-
and polyfluoroalkyl substances, or PFAS, and 1,4-dioxane into downstream drinking water
supplies in the Catawba River basin. Among other industrial users, McAlpine receives
wastewater from Brenntag Midsouth, a chemical manufacturer that likely uses PFAS and is a
known source of 1,4-dioxane elsewhere in the state, and from DyStar Carolina Chemical, which
has been shown to release high amounts of 1,4-dioxane at other facilities in North Carolina.
McAlpine did not disclose its likely PFAS or 1,4-dioxane discharges 4 and despite
acknowledging that McAlpine’s industrial users likely use and release the chemicals,5 the

1 N.C. Dep’t of Env’t Quality, Draft NPDES Permit NC0024970 (May 2, 2023) [hereinafter “McAlpine Draft
Permit”].
2 N.C. Dep’t of Env’t Quality, Draft Fact Sheet NPDES Permit No. NC0024970 (May 2, 2023), at 1–2 [hereinafter
“McAlpine Draft Fact Sheet”].
3 See Water and Sewer, Union County NC, https://www.unioncountync.gov/government/departments-r-
z/water/water-and-sewer (last visited June13, 2023); Lancaster County Water and Sewer District, 2022 Annual
Drinking Water Report (2022), https://www.lcwasd.org/sites/default/files/uploads/5-2-
22_draft_of_lcwsd_2021_water_quality_report_draft.pdf.
4 See generally Charlotte Water, Permit Renewal Application (Jan. 5, 2021) [hereinafter “McAlpine 2021 Permit
Application”].
5 McAlpine Draft Fact Sheet, supra note 2 at 10.

2

Department did not evaluate limits for PFAS or 1,4-dioxane in the draft permit.6 Instead the
Department incorporated mere monitoring requirements for both chemicals and a reopener for
1,4-dioxane.7 Because McAlpine did not disclose discharges of PFAS and 1,4-dioxane, and the
Department did not evaluate limits for the chemicals in its draft permit, as required by the Clean
Water Act and state laws, any permit issued by the agency will necessarily prohibit all discharges
of the chemicals.
While it is true that the Department has the authority to issue a permit that allows PFAS
and 1,4-dioxane discharges, it cannot do so by ignoring the pollution and executing a monitoring
condition. As the U.S. Environmental Protection Agency (“EPA”) made clear in guidance issued
last December, state permitting agencies should use their “existing authorit[y]” to control toxic
chemical pollution, including PFAS, “to the fullest extent available under state and local law.”8
EPA’s PFAS NPDES Guidance highlights central tenets of the NPDES permitting program—
including effluent limitations and the pretreatment program—that are effective at controlling
PFAS pollution.9 Those same tools can and should be used to control 1,4-dioxane. Because this
draft permit does not impose effluent limits for these chemicals or require McAlpine to utilize its
pretreatment program to control pollution flowing from its significant industrial users, it is
unlawful and must be withdrawn and revised.
I. PFAS and 1,4-dioxane are harmful to human health and the environment.
PFAS are a group of man-made chemicals manufactured and used broadly by industry
since the 1940s.10 PFAS pose a significant threat to human health at extremely low
concentrations. Two of the most studied PFAS––perfluorooctanoic acid (“PFOA”) and
perfluorooctane sulfonate (“PFOS”)––are bioaccumulative and highly persistent in humans.11
PFOA and PFOS have been shown to cause developmental effects to fetuses and infants, kidney
and testicular cancer, liver malfunction, hypothyroidism, high cholesterol, ulcerative colitis,
obesity, decreased immune response to vaccines, reduced hormone levels, delayed puberty,
fertility concerns, and lower birth weight and size.12 Because of their impacts on the immune

6 McAlpine Draft Permit, supra note 1 at 3, 13; McAlpine Draft Fact Sheet, supra note 2 at 10.
7 McAlpine Draft Permit, supra note 1 at 3.
8 Memorandum from Radhika Fox, Assistant Administrator, U.S. Env’t Prot. Agency, Addressing PFAS Discharges
in NPDES Permits and Through the Pretreatment Program and Monitoring Programs (December 5, 2022)
(emphasis added) [hereinafter “EPA’s PFAS NPDES Guidance”], Attachment 1.
9 Id. at 3–4.
10 Lifetime Drinking Water Health Advisories for Four Perfluoroalkyl Substances, 87 Fed. Reg. 36,848, 36,849
(June 21, 2022); Our Current Understanding of the Human Health and Environmental Risks of PFAS, U.S. ENV’T
PROT. Agency, https://www.epa.gov/pfas/our-current-understanding-human-health-and-environmental-risks-pfas
(last visited Sept. 12, 2022).
11 87 Fed. Reg. at 36,849; U.S. Env’t Prot. Agency, Interim Drinking Water Health Advisory: Perfluorooctanoic
Acid (PFOA) CASRN 335-67-1 (June 2022), at 3–4, available at
https://www.epa.gov/system/files/documents/2022-06/interim-pfoa-2022.pdf; U.S. Env’t Prot. Agency, Interim
Drinking Water Health Advisory: Perfluorooctane Sulfonic Acid (PFOS) CASRN 1763-23-1 (June 2022), at 3–4,
available at https://www.epa.gov/system/files/documents/2022-06/interim-pfos-2022.pdf.
12 Arlene Blum et al., The Madrid Statement on Poly- and Perfluoroalkyl Substances (PFASs), 123 Env’t. Health
Persp. 5, A 107 (May 2015); U.S. Env’t Prot. Agency, Drinking Water Health Advisories for PFAS: Fact Sheet for
Communities, at 1–2 (June 2022), available at https://www.epa.gov/system/files/documents/2022-06/drinking-
water-ha-pfas-factsheet-communities.pdf; Nathan J. Cohen, Exposure to Perfluoroalkyl Substances and Women’s

3

system, PFAS can also exacerbate the effects of Covid-19.13 Studies show that exposure to
mixtures of different PFAS can worsen these health effects.14 Given these harms, EPA in June
2022, established interim updated lifetime health advisories for PFOA and PFOS in drinking
water of 0.004 and 0.02 parts per trillion (“ppt”), respectively.15
Other PFAS are similarly harmful. For instance, EPA has set final lifetime health
advisories for hexafluoropropylene oxide (HFPO) dimer acid and its ammonium salt (“GenX”)
in drinking water of 10 ppt.16 Building upon its understanding of the harms caused by PFAS, on
March 14, 2023, EPA proposed national drinking water standards for six PFAS compounds.17 As
drafted, EPA proposes to limit concentrations of PFOA and PFOS in drinking water systems to
below 4 ppt, with a public health goal of 0 ppt.18 EPA also proposed to limit perfluorononanoic
acid (“PFNA”), perfluorobutanesulfonic acid (“PFBS”), perfluorohexanesulphonic acid
(“PFHxS”), and GenX as a mixture, utilizing a formula called a hazard index.19 In light of the
proposed drinking water standards, it is clear we must prevent as much of this pollution from
entering our rivers, creeks, and streams as possible.

Fertility Outcomes in a Singaporean Population-Based Preconception Cohort, 873 SCI. TOTAL ENV’T 162267 (May
15, 2023).
13 See Lauren Brown, Insight: PFAS, Covid-19, and Immune Response–Connecting the Dots, Bloomberg Law (July
13, 2020, 4:00 AM), https://news.bloomberglaw.com/environment-and-energy/insight-pfas-covid-19-and-immune-
response-connecting-the-dots?context=article-related.
14 Emma V. Preston et al., Prenatal Exposure to Per- and Polyfluoroalkyl Substances and Maternal and Neonatal
Thyroid Function in the Project Viva Cohort: A Mixtures Approach, 139 ENV’T INT’L 1 (2020),
https://perma.cc/DJK3-87SN.
15 87 Fed. Reg. at 36,848–49.
16 Id.
17 See Proposed PFAS National Primary Drinking Water Regulation, U.S. Env’t Prot. Agency (Mar. 14, 2023); see
also 88 Fed. Reg. at 18,639.
18 Id. at 18,639.
19 Id. at 18,639–40.

4

PFAS are also harmful to wildlife and the environment. The chemicals have been shown
to cause damaging effects in fish,20 amphibians,21 mollusks,22 and other aquatic invertebrates 23—
resulting in developmental and reproductive impacts, behavioral changes, adverse effects to
livers, disruption to endocrine systems, and weakened immune systems.24 Moreover, PFAS are
extremely resistant to breaking down in the environment, can travel long distances, and bio-
accumulate in organisms.25 PFAS have been found in fish tissue, and communities that rely
heavily on fishing have been found to have elevated PFAS levels in their blood.26

20 Chen et al., Perfluorobutanesulfonate Exposure Causes Durable and Transgenerational Dysbiosis of Gut
Microbiota in Marine Medaka, 5 ENV’T SCI. & TECH LETTERS 731–38 (2018); Chen et al., Accumulation
of Perfluorobutane Sulfonate (PFBS) and Impairment of Visual Function in the Eyes of Marine Medaka After
a LifeCycle Exposure, 201 AQUATIC TOXICOLOGY 1–10 (2018); Du et al., Chronic Effects of Water-Borne PFOS
Exposure on Growth, Survival and Hepatotoxicity in Zebrafish: A Partial Life-Cycle Test, 74 CHEMOSPHERE 723–29
(2009); Hagenaars et al., Structure–Activity Relationship Assessment of Four Perfluorinated Chemicals Using a
Prolonged Zebrafish Early Life Stage Test, 82 CHEMOSPHERE 764–72 (2011); Huang et al., Toxicity, Uptake
Kinetics and Behavior Assessment in Zebrafish Embryos Following Exposure
to Perfluorooctanesulphonicacid (PFOS), 98 AQUATIC TOXICOLOGY 139–47 (2010); Jantzen et al., PFOS, PFNA,
and PFOA Sub-Lethal Exposure to Embryonic Zebrafish Have Different Toxicity Profiles in terms of
Morphometrics, Behavior and Gene Expression, 175 AQUATIC TOXICOLOGY 160–70 (2016); Liu et al., The Thyroid-
Disrupting Effects of Long-Term Perfluorononanoate Exposure on Zebrafish (Danio rerio),
20 ECOTOXICOLOGY 47–55 (2011); Chen et al., Multigenerational Disruption of the Thyroid Endocrine System in
Marine Medaka after a Life-Cycle Exposure to Perfluorobutanesulfonate, 52 ENV’T SCI. & TECH. 4432–39
(2018); Rotondo et al., Environmental Doses of Perfluorooctanoic Acid Change the Expression of Genes in Target
Tissues of Common Carp, 37 ENV’T TOXICOLOGY & CHEM. 942–48 (2018).
21 Ankley et al., Partial Life-Cycle Toxicity and Bioconcentration Modeling of Perfluorooctanesulfonate in the
Northern Leopard Frog (Rana Pipiens), 23 ENV’T TOXICOLOGY & CHEM. 2745 (2004); Cheng et al., Thyroid
Disruption Effects of Environmental Level Perfluorooctane Sulfonates (PFOS) in Xenopus Laevis,
20 ECOTOXICOLOGY 2069–78 (2011); Lou et al., Effects
of Perfluorooctanesulfonate and Perfluorobutanesulfonate on the Growth and Sexual Development of
Xenopus Laevis, 22 ECOTOXICOLOGY 1133–44 (2013).
22 Liu et al., Oxidative Toxicity of Perfluorinated Chemicals in Green Mussel and Bioaccumulation Factor
Dependent Quantitative Structure-Activity Relationship, 33 ENV’T TOXICOLOGY & CHEM. 2323–32 (2014); Liu et
al., Immunotoxicity in Green Mussels under Perfluoroalkyl Substance (PFAS) Exposure: Reversible Response and
Response Model Development, 37 ENV’T TOXICOLOGY & CHEM. 1138–45 (2018).
23 Houde et al., Endocrine-Disruption Potential of Perfluoroethylcyclohexane Sulfonate (PFECHS) in Chronically
Exposed Daphnia Magna, 218 ENV’T POLLUTION 950–56 (2016); Liang et al., Effects of Perfluorooctane Sulfonate
on Immobilization, Heartbeat, Reproductive and Biochemical Performance of Daphnia Magna,
168 CHEMOSPHERE 1613–18 (2017); Ji et al., Oxicity of Perfluorooctane Sulfonic Acid and Perfluorooctanoic Acid
on Freshwater Macroinvertebrates (Daphnia Magna and Moina Macrocopa) and Fish (Oryzias Latipes), 27 ENV’T
TOXICOLOGY & CHEM. 2159 (2008); MacDonald et al., Toxicity of Perfluorooctane Sulfonic Acid and
Perfluorooctanoic Acid to Chironomus Tentans, 23 ENV’T TOXICOLOGY & CHEM. 2116 (2004).
24 See supra notes 20-22.
25What are PFAS?, Agency for Toxic Substances and Disease Registry, https://www.atsdr.cdc.gov/pfas/health-
effects/overview.html (last visited June 13, 2023); see also Our Current Understanding of the Human Health and
Environmental Risks of PFAS, supra note 10.
26 Patricia A. Fair et al., Perfluoralkyl Substances (PFASs) in Edible Fish Species from Charleston Harbor and
Tributaries, South Carolina, United States: Exposure and Risk Assessment, 171 ENV’T. RES. 266 (April
2019); Chloe Johnson, Industrial chemicals in Charleston Harbor taint fish – and those who eat them, POST &
COURIER (June 4, 2022), https://www.postandcourier.com/environment/industrial-chemicals-in-charleston-harbor-
taint-fish-and-those-who-eat-them/article_b2b14506-bc19-11ec-83e5-7f2a8322d624.html.
5
Like PFAS, 1,4-dioxane is toxic to humans.27 1,4-dioxane is a clear, man-made chemical
that is a byproduct of many industrial processes.28 The chemical has been shown to cause liver
and kidney damage at incredibly low levels.29 As a result of the harms caused by 1,4-dioxane,
EPA established a drinking water health advisory with an associated lifetime cancer risk of one-
in-one-million at a concentration of 0.35 parts per billion (“ppb”).30 North Carolina has similarly
determined that 1,4-dioxane is toxic and poses a cancer risk at levels higher than 0.35 ppb.31
II.McAlpine’s Industrial Users Likely Use and Discharge PFAS and 1,4-dioxane.
Many of McAlpine’s significant industrial users are likely discharging PFAS and 1,4-
dioxane into the utility’s sewer system.32 For example, Brenntag Mid-South, one of McAlpine’s
significant industrial users,33 is a chemical re-packager and distributer that generates hazardous
waste.34 EPA has found that chemical manufacturing industries like Brenntag are likely sources
of PFAS35 and pollution reports taken from other Brenntag locations confirm the company is a
source of 1,4-dioxane.36 Brenntag’s Durham facility, for instance, discharges the chemical at
concentrations exceeding 270 ppb,37 and Brenntag’s Greensboro facility has discharged the
chemical at levels at least as high as 9 ppb.38 In addition to Brenntag’s likely PFAS and 1,4-
dioxane pollution, EPA has identified Brenntag’s Charlotte location as a “significant
noncomplier” with its waste disposal obligations in 8 of the past 12 quarters—suggesting a wide
27 U.S. Env’t Prot. Agency, Technical Fact Sheet – 1,4-Dioxane 1-2 (2017), Attachment 2 [hereinafter “EPA,
Technical Fact Sheet – 1,4-Dioxane”].
28 Id.
29 Id.; U.S. Env’t Prot. Agency, Integrated Risk Information System, Chemical Assessment Summary: 1,4,-dioxane 2
https://iris.epa.gov/static/pdfs/0326_summary.pdf (Aug. 11, 2010).
30 2018 Edition of the Drinking Water Standards and Health Advisories, EPA OFFICE OF WATER 4 (2018),
https://www.epa.gov/system/files/documents/2022-01/dwtable2018.pdf.
31 N.C. Div. of Water Res., 1,4-dioxane Monitoring in the Cape Fear River Basin of North Carolina: An Ongoing
Screening, Source Identification, and Abatement Verification Study 2 (2017) [hereinafter “NCDWR, 1,4-dioxane
2017 Report”] (affirming EPA’s conclusions); see also N.C. Dep’t of Env’t Quality, Div. Water Res., Surface Water
Quality Standards, Criteria & In-Stream Target Values (2019) (stating that the one-in-one million cancer risk for
1,4-dioxane is 0.35 ppb), Attachment 3.
32 We note that McAlpine’s permitting materials do not provide a complete and updated list of the utility’s industrial
users nor the industry codes associated with each. As such, McAlpine should amend or supplement its permitting
materials with this information so that the Department and the public are fully informed about the likely sources of
toxic chemical pollution. For the purposes of this comment letter, we rely on public records obtained from the
Department listing significant industrial users at the facility. See N.C. Dep’t of Env’t Quality, List of Significant
Industrial Users by Wastewater Treatment Plant (2019), at 2, Attachment 4.
33 Id. at 2.
34 See Andrew Martin, N.C. Dep’t of Env’t Quality, Compliance Schedule Evaluation, NCD986229623, Brenntag
Mid-South, Inc – Charlotte (Apr. 5, 2022), Attachment 5.
35 U.S. Env’t Prot. Agency, Effluent guidelines Program Plan 15 (Jan. 2023), at 7-3, available at
https://www.epa.gov/system/files/documents/2023-01/11143_ELG%20Plan%2015_508.pdf [hereinafter “EPA,
Program Plan 15”].
36 See e.g., March 2021 Brenntag Mid-South Inc. Discharge Monitoring Report – Permit No. NC0086827,
Attachment 6.
37 See id.; see also Letter from Geoff Gisler, et al., S. Env’t L. Ctr., to Emily DelDuco Richards, N.C. Dep’t of Env’t
Quality (July 12, 2021), Attachment 7.
38 N.C. Dep’t of Env’t Quality, Cape Fear Industrial PFAS & 1,4-dioxane Sampling (2020), Attachment 8; see also
Letter from Geoff Gisler, et al., S. Env’t Law Ctr., to Brianna Young, N.C. Dep’t of Env’t Quality (Aug. 27, 2021),
Attachment 9.

6

scope of harmful pollution.39 Given Brenntag’s other operations, it is likely that it releases 1,4-
dioxane and PFAS into McAlpine’s sewer system.
Like Brenntag, DyStar is also likely discharging 1,4-dioxane to McAlpine’s sewer
system.40 McAlpine does not disclose any sampling data taken from DyStar, but sampling
conducted at DyStar’s Reidsville location confirms that that the company releases extraordinarily
high concentrations of the toxic chemical. Concentrations of 1,4-dioxane discharged from
DyStar into the Reidsville wastewater treatment plant have been documented as high as 678,000
ppb, with an average of approximately 53,000 ppb.41 Because the Reidsville wastewater
treatment plant cannot treat or remove the 1,4-dioxane, the toxic chemical flows through the
plant and into the city’s effluent.42 In part because of DyStar, Reidsville is one of the largest
sources of 1,4-dioxane in the Cape Fear River Basin.43 Given DyStar’s operations elsewhere, it
is likely that the company is releasing 1,4-dioxane into McAlpine’s sewer system.
Other users are likely discharging PFAS and 1,4-dioxane to McAlpine as well. In total,
McAlpine has between 17 44 and 24 45 significant industrial users. Many of those users appear to
be industries that EPA suspects to use or release PFAS like chemical manufacturing, synthetic
paper, textiles, and landfills.46 EPA has noted that these industries either use or receive PFAS
waste and likely discharge wastewater laden with these toxic chemicals.47
McAlpine does not include information about its industrial users, or their industry codes,
in its permit application materials 48 rendering it difficult for the Department and the public to
understand the full scope of pollution flowing from the wastewater plant and the likely sources.
What is known, however, is that downstream drinking water supplies contain PFAS. South
Carolina’s Department of Health and Environmental Control has identified PFAS, including
PFOA and PFOS, in Catawba River Water Supply Project’s drinking water 49 suggesting that
McAlpine’s pollution could be reaching downstream communities.

39 May 2023 Brenntag Southeast TRI Facility Report – Permit NCD986229623, https://echo.epa.gov/detailed-
facility-report?fid=110000349711.
40 See List of Significant Industrial Users by Wastewater Treatment Plant, supra note 32 at 2.
41 City of Reidsville, 1,4-dioxane Sample Results (Dec. 2017-Apr. 2020), Attachment 10.
42 City of Reidsville, DyStar Wastewater Discharge and the City of Reidsville (2020) (showing the impact that
DyStar’s discharge has on Reidsville’s effluent), Attachment 11.
43 N.C. Dep’t of Env’t Quality, 1,4-Dioxane in the Cape Fear River Basin of North Carolina: An Initial Screening
and Source Identification Study (2016), at 4 https://www.deq.nc.gov/water-quality/environmental-
sciences/eco/dioxanereport-yr1final-20160127/download.
44 McAlpine Draft Fact Sheet, supra note 2 at 1.
45 McAlpine 2021 Permit Application, supra note 4 at PDF page 12.
46 See generally EPA, Program Plan 15, supra note 35; U.S. Env’t Prot. Agency, Multi-Industry Per- and
Polyfluoroalkyl Substances (PFAS) Study – 2021 Preliminary Report (Sept. 2021), at 5-1 to 8-3,
https://www.epa.gov/system/files/documents/2021-09/multi-industry-pfas-study_preliminary-2021-
report_508_2021.09.08.pdf [hereinafter “EPA, Preliminary Industry Report”].
47 See generally EPA, Preliminary Industry Report, supra note 46.
48 See McAlpine 2021 Permit Application, supra note 4 at PDF page 12.
49 S.C. Dep’t of Health and Env’t Control, Table 1. PFOA and PFOS Data from Surface Water-Source Community
Drinking Water Systems (Aug. 2020), https://scdhec.gov/sites/default/files/media/document/Table%201.pdf; S.C.
Dep’t of Health and Env’t Control, Table 2. Other PFAS Data (excluding PFOA and PFOS) by EPA Method 537.1
from Surface Water-Sourced Community Drinking Water Systems (Aug. 2020),

7

III. The Department must require McAlpine to disclose any PFAS and 1,4-dioxane that
it is discharging from the McAlpine wastewater plant.
McAlpine did not disclose its likely PFAS or 1,4-dioxane pollution. During the permit
application process, the Department asked McAlpine whether it had sampled its own effluent or
the wastewater from its industrial users for 1,4-dioxane or any other “additional parameters.”50
McAlpine responded that “no SIU’s in [the] Pretreatment Program have been sampled for 1,4
Dioxane” and that no sampling had taken place at the wastewater plant.51 As a result, McAlpine
refused to fill out the chemical addendum the Department uses, in part, to determine if a facility
has data on PFAS or 1,4-dioxane discharges, stating that “no additional parameters have been
sampled for” since the application was submitted.52
This lack of disclosure makes any discharges of PFAS or 1,4-dioxane unlawful. The
Clean Water Act prohibits the discharge of any pollutant, including PFAS and 1,4-dioxane,
without a NPDES permit.53 The discharge of a specific pollutant (or group of pollutants) cannot
be permitted if it is not disclosed in a NPDES permit application. For decades, EPA has stressed
the need for disclosure of pollutants during the permitting process:
[D]ischargers have a duty to be aware of any significant pollutant levels in their
discharge. […] Most important, [the disclosure requirements] provide the
information which the permit writers need to determine what pollutants are likely
to be discharged in significant amounts and to set appropriate permit limits. […]
[P]ermit writers need to know what pollutants are present in an effluent to
determine appropriate permit limits in the absence of applicable effluent
guidelines.54
In December 2022, EPA confirmed that these disclosure requirements apply to PFAS,
stating that “no permit may be issued to the owner or operator of a facility unless the owner or
operator submits a complete permit application” providing all information “that the permitting
authority may reasonably require to assess the discharges of the facility” including information
regarding PFAS.55 The Department has similarly made clear that disclosure of toxic PFAS is
required by the Clean Water Act and state water quality laws. In its enforcement action against
Chemours for the company’s discharge of PFAS into the Cape Fear River, the agency concluded

https://scdhec.gov/sites/default/files/media/document/Table%202.pdf; S.C. Dep’t of Health and Env’t Control, Other
PFAS Data (excluding PFOA and PFOS) by EPA Method 533 from Surface Water-Sourced Community Drinking
Water Systems (Aug. 2020), https://scdhec.gov/sites/default/files/media/document/Table%203.pdf.
50 McAlpine Draft Fact Sheet, supra note 2 at PDF page 37–43.
51 Id. at PDF page 38.
52 Id. at PDF page 39–40.
53 33 U.S.C. § 1311(a).
54 Consolidated Permit Application Forms for EPA Programs, 45 Fed. Reg. 33,526–31 (May 19, 1980).
55 EPA’s PFAS NPDES Guidance, supra note 8 at 2.

8

that because Chemours had not disclosed its PFAS pollution, the discharges violated the law.56
These disclosure requirements—a central tenet of the NPDES program—apply to 1,4-dioxane.
Disclosure is considered adequate under the Clean Water Act when the applicant
provides enough information for a permitting agency to “be[] able to judge whether the discharge
of a particular pollutant constitutes a significant threat to the environment.”57 To meet this
burden, an applicant must include all relevant information, including the concentration, volume,
and frequency of the discharge.58 The Clean Water Act places the burden of disclosure on the
permit applicant because they are in the best position to know what is in their discharge.59
Importantly, if a NPDES permit applicant does not adequately disclose its release of a
pollutant, the applicant does not have the approval to discharge the pollutant.60 The EPA
Environmental Appeals Board’s decision in In re: Ketchikan Pulp Company emphasized this
result,61 and that decision has been adopted by the Fourth Circuit.62 The Department recognized
this is the law in its enforcement action against Chemours,63 and other states have reached the
similar conclusion.64 Because McAlpine failed to disclose that it discharges PFAS and 1,4-
dioxane, each and every release of these chemicals—should they occur—would be a violation of
the Clean Water Act subject to enforcement by the Department or citizen suit brought under 33
U.S.C. § 1365.

56 Amended Complaint, N.C. Dept. of Environmental Quality v. Chemours, 17 CVS 580, 6–7 (N.C. Super. 2018)
(citing 33 U.S.C. § 1342(k); Piney Run Pres. Ass’n v. Cty. Comm’rs of Carroll Cty., Maryland, 268 F.3d. 255, 265
(4th Cir. 2001)) [hereinafter “DEQ v. Chemours, Amended Complaint”], https://files.nc.gov/ncdeq/GenX/2018-04-
09%20FINAL%20Amended%20Chemours%206C%20Complaint.pdf.
57 Piney Run, 268 F.3d. at 268 (“Because the permitting scheme is dependent on the permitting authority being able
to judge whether the discharge of a particular pollutant constitutes a significant threat to the environment, discharges
not within the reasonable contemplation of the permitting authority during the permit application process, whether
spills or otherwise, do not come within the protection of the permit shield.”).
58 See In re Ketchikan Pulp Co., 7 E.A.D. 605 (EPA) (1998) (“In explaining the provisions of 40 C.F.R. §
122.53(d)(7)(iii), which required dischargers to submit quantitative data relating to certain conventional and
nonconventional pollutants that dischargers know or have reason to believe are present in their effluent, the [EPA]
stated: ‘permit writers need to know what pollutants are present in an effluent to determine appropriate limits in the
absence of effluent guidelines.’”).
59 S. Appalachian Mountain Stewards v. A & G Coal Corp., 758 F.3d 560, 566 (4th Cir. 2014).
(“The statute and regulations purposefully place the burden of disclosure on the permit applicant.”).
60 See In re Ketchikan Pulp Co., 7 E.A.D. 605; Piney Run, 268 F.3d. at 268; S. Appalachian Mountain Stewards, 758
F.3d at 567.
61 See In re Ketchikan Pulp Co., 7 E.A.D. 605.
62 Piney Run, 268 F.3d. at 268 (“The Ketchikan decision, therefore, made clear that a permit holder is in compliance
with the [Clean Water Act] even if it discharges pollutants that are not listed in its permit, as long as it only
discharges pollutants that have been adequately disclosed to the permitting authority. […] To the extent that a permit
holder discharges a pollutant that it did not disclose, it violates the NPDES permit and the [Clean Water Act].”).
63 DEQ v. Chemours, Amended Complaint, supra note 56 at 6–7 (N.C. Super. 2018) (citing 33 U.S.C. § 1342(k);
Piney Run, 268 F.3d at 265).
64 For example, the Tennessee Department of Environment and Conservation has made clear in at least one NPDES
permit that undisclosed discharges of PFAS are unpermitted, stating, “The facility’s application did not report any
forms of PFAS as chemicals that there was the potential to discharge. The permittee has no permit shield for the
discharge of PFAS compounds because no such chemicals were disclosed in the permit application or otherwise…”
TDEC, NPDES Permit NO. TN0002330 (2020), Holliston Holdings, LLC, Addendum to Rationale,
https://perma.cc/4RKY-PKFG (emphasis added).

9

The Department must require McAlpine to disclose any discharge of PFAS or 1,4-
dioxane in its permit application before moving forward with this NPDES permit. The
Department should direct McAlpine to analyze its effluent for PFAS using EPA recommended
draft method 1633 and draft method 1621,65 and for 1,4-dioxane using methods approved under
40 C.F.R. part 136. The agency should then direct McAlpine to disclose any pollutants found
through this sampling.66 The Department must require disclosure to ensure regulated parties
know of their obligations with respect to PFAS and 1,4-dioxane and are aware of the potential
liability if they fail to do so.
IV. The Department must analyze effluent limits and conditions for PFAS and 1,4-
dioxane in McAlpine’s NPDES permit.
In December 2022, EPA released guidance instructing state agencies how to address
PFAS through existing NPDES authorities.67 The same tools in the guidance should be used for
1,4-dioxane. Federal and state law, as well as EPA’s guidance make clear that the Department
must consider effluent limits and permit conditions to control McAlpine’s likely pollution.
If McAlpine is discharging PFAS or 1,4-dioxane, the Department must consider
appropriate permit limits for the plant’s renewal NPDES permit. The Clean Water Act requires
permitting agencies to, at the very least, incorporate, technology-based effluent limitations on the
discharge of pollutants.68 When EPA has not issued a national effluent limitation guideline for a
particular industry,69 permitting agencies must implement technology-based effluent limits on a
case-by-case basis using their “best professional judgment.”70 North Carolina water quality laws
further state that utilities must be treated like an industrial discharger if an industrial user
“significantly impact[s]” a wastewater treatment system.71 In this situation, the agency must
consider technology-based effluent limits for the utility, even if effluent limits and guidelines
have not been published and adopted.72
Effective treatment technologies for PFAS and 1,4-dioxane are available. Granular
activated carbon is a cost effective and efficient technology that is capable of reducing PFAS
concentrations to virtually nondetectable levels. A granular activated carbon treatment system at
the Chemours’ facility, for example, has reduced PFAS concentrations as high as 345,000 ppt
from a creek contaminated by groundwater beneath the facility to nearly nondetectable

65 Draft method 1633 tests for 40 PFAS compounds in a variety of media, while draft method 1621 is a screening
method that can identify the presence of thousands of known PFAS but does not identify the specific PFAS that are
present. CWA Analytical Methods for Per- and Polyfluorinated Alkyl Substances (PFAS), U.S. ENV’T PROT.
AGENCY, https://www.epa.gov/cwa-methods/cwa-analytical-methods-and-polyfluorinated-alkyl-substances-pfas
(last visited Sept. 12, 2022).
66 EPA recommends the use these methods for NPDES permits. See EPA’s NPDES PFAS Guidance, supra note 8 at
2, 4.
67 Id. at 4.
68 40 C.F.R. § 125.3(a); see also 33 U.S.C. § 1311.
69 33 U.S.C. § 1314(b).
70 40 C.F.R. § 125.3; see also 33 U.S.C. § 1342(a)(1)(B); 15A N.C. Admin. Code 2B.0406.
71 15A N.C. Admin. Code 2B .0406(a).
72 Id.

10

concentrations.73 Similarly, 1,4-dioxane can be removed using advanced oxidation processes,
such as using ultraviolet light in combination with hydrogen peroxide.74 Such a process has been
used at the Tucson International Airport Area Superfund Site to remove legacy 1,4-dioxane
contamination.75 That treatment system is able to remove over 97 percent of the chemical from
polluted water.76 The Department must consider the feasibility of McAlpine or its industrial
users installing these technologies or similarly effective technologies.
If technology-based limits are not enough to ensure compliance with water quality
standards, the Department must include water quality-based effluent limits in the permit.77 North
Carolina’s toxic substances standard protects the public from the harmful effects of toxic
chemicals, like PFAS and 1,4-dioxane.78 For instance, the toxic substances standard mandates
that the concentration of cancer-causing chemicals, like PFAS and 1,4-dioxane, shall not result in
“unacceptable health risks,” defined as “more than one case of cancer per one million people
exposed.”79 In order to comply with the Clean Water Act, therefore, the Department must
analyze appropriate treatment technology and then determine if a discharger’s pollution has the
“reasonable potential to cause, or contribute” to pollution at levels that could harm human
health.80
The Department has analyzed the need for and ultimately set limits for 1,4-dioxane in
draft and final NPDES permits issued to other wastewater plants in North Carolina. The
Department used the narrative toxic substances standard to determine that the city of Sanford did
not have the reasonable potential to violate water quality laws and therefore did not need an
effluent limit.81 Using the same standard, the Department set effluent limits for 1,4-dioxane in a
draft permit issued to the city of Asheboro.82 Like with 1,4-dioxane, the Department has set
limits for PFAS in at least one NPDES permit referencing the toxic substances standard.83

73 See Parsons, Engineering Report – Old Outfall 002 GAC Pilot Study Results (Sept. 2019), available at
https://www.chemours.com/ja/-/media/files/corporate/12e-old-outfall-2-gac-pilot-report-2019-09-
30.pdf?rev=6e1242091aa846f888afa895eff80e2e&hash=040CAA7522E3D64B9E5445ED6F96B0FB; see also
Chemours Outfall 003, NPDES No. NC0089915 Discharge Monitoring Reports (2020–2022), available at
https://perma.cc/8YND-XT5M.
74 Amie C. McElroy, et al., 1,4-Dioxane in drinking water: emerging for 40 years and still unregulated, 7 CURRENT
OPINION IN ENV’T SCIENCE & HEALTH 117, 119 (2019), available at https://agris.fao.org/agris-
search/search.do?recordID=US201900256076.
75 See Advanced Treatment for 1,4-Dioxane – Tucson Removes Contamination Through UV-oxidation, TROJANUV
CASESTUDIES (2019), available at https://www.resources.trojanuv.com/wp-content/uploads/2018/05/Treatment-of-
Groundwater-Contaminated-with-14-Dioxane-Tucson-Arizona-Case-Study-Environmental-Contaminant-
Treatment.pdf.
76 Id. at 2; see also Educational Brochure, TUCSON AIRPORT AREA REMEDIATION PROJECT, available at
https://www.tucsonaz.gov/files/water/docs/AOP_TARP_educational_signs.pdf.
77 40 C.F.R. § 122.44(d)(1)(i); see also 33 U.S.C. § 1311(b)(1)(C); 15A N.C. Admin. Code 2H.0112(c) (stating that
Department must “reasonably ensure compliance with applicable water quality standards and regulations”).
78 15A N.C. Admin. Code 2B.0208.
79 Id. at 2B.0208(a)(2)(B).
80 40 C.F.R. § 122.44(d)(1)(i).
81 See N.C. Dep’t of Env’t Quality, Final Fact Sheet NPDES Permit No. NC0024147 (Apr. 14, 2023), Attachment
12.
82 See N.C. Dep’t of Env’t Quality, Draft NPDES Permit NC0026123 (Dec. 6, 2022), at 3, Attachment 13.
83 See N.C. Dep’t of Env’t Quality, NPDES Permit NC0090042 (Sept. 15, 2022), Attachment 14.

11

In order to comply with the Clean Water Act, therefore, if McAlpine discharges these
chemicals, the Department must limit its discharge so that it will not “cause, or contribute” to
concentrations in excess of levels protective of human health.
V. The Department should impose conditions in this permit that require McAlpine to
control pollution through its pretreatment program.
By setting limits and conditions in McAlpine’s permit, the Department can ensure that
McAlpine properly regulates its industrial users so that they do not release uncontrolled PFAS or
1,4-dioxane into the environment and downstream drinking water supplies.84
The Clean Water Act pretreatment program requires a wastewater treatment plant to
know what it is receiving from its industries, and EPA has confirmed that this requirement
extends to pollutants that are not conventional or listed as toxic, like PFAS.85 Wastewater
treatment plants, like McAlpine, must instruct their industries to identify their pollutants in an
industrial waste survey 86 and, when applying for a pretreatment permit, to disclose “effluent
data,” including on internal waste streams when necessary to evaluate pollution controls.87
Significant industrial users are further required to provide information “[p]rincipal products and
raw materials . . . that affect or contribute to the [significant industrial user’s] discharge.”88 To
ensure that utilities use their existing pretreatment authority, EPA’s NPDES PFAS Guidance
recommends that permits issued to wastewater treatment plants include a permit requirement to
identify industrial users in industry categories “expected or suspected of PFAS discharges.”89
The same requirements apply to 1,4-dioxane. Because McAlpine’s significant industrial users
engage in activities which are known to discharge 1,4-dioxane and PFAS, the Department should
follow EPA’s guidance and include a condition in McAlpine’s permit that requires the utility to
update its industrial user survey and determine the volume of these toxic chemicals, if any, being
sent to the wastewater treatment plant.
If after survey, McAlpine learns that its significant industrial users discharge PFAS or
1,4-dioxane, the Clean Water Act gives McAlpine the tools it needs to control the discharges and
ensure the industries do not cause the treatment plant to violate its own NPDES permit.90
McAlpine can establish local limits for the pollutants,91 or can go beyond pretreatment permit
limits and incorporate permit conditions including “[r]equirements for the installation of
pretreatment technology, pollution control, or construction of appropriate containment devices,

84 40 C.F.R. § 403.8(f)(1).
85 See EPA’s PFAS NPDES Guidance, supra note 8 at 4.
86 40 C.F.R. § 403.8(f)(2)(ii); U.S. Env’t Prot. Agency, Introduction to the National Pretreatment Program, at 4-3
(Jun. 2011), available at https://www.evansvillegov.org/egov/documents/1499266949_62063.pdf.
87 U.S. Env’t Prot. Agency, Industrial User Permitting Guidance Manual (2012), at 4-2 to 4-3, available at
https://www.epa.gov/sites/default/files/2015-10/documents/industrial_user_permitting_manual_full.pdf.
88 40 C.F.R. § 122.21(j)(6)(ii)(C).
89 EPA’s PFAS NPDES Guidance, supra note 8 at 4.
90 40 C.F.R. § 403.8(f)(1).
91 See U.S. Env’t Prot. Agency, Local Limits Development Guidance (July 2004), at 5-11 to 5-21, available at
https://www3.epa.gov/npdes/pubs/final_local_limits_guidance.pdf. Wastewater treatment plants, like McAlpine,
also have discretion to set permit limits for industrial users through a case-by-case analysis “based on the
discharger’s current loading, its need for a continued loading allocation, its ability to apply pretreatment to achieve
certain discharge pollutant levels (i.e. treatability), or any other factor that the [wastewater treatment plant]
determines is relevant.” Id. at 6-12.

12

designed to reduce, eliminate, or prevent the introduction of pollutants into the treatment
works.”92 Regulating wastewater plants this way is how the Clean Water Act “assures the public
that [industrial] dischargers cannot contravene the [Clean Water Act’s] objectives of eliminating
or at least minimizing discharges of toxic and other pollutants simply by discharging indirectly
through [wastewater plants] rather than directly to receiving waters.”93
VI. Conclusion.
In summary, the Department must require McAlpine to disclose any discharges of PFAS
and 1,4-dioxane in its permit application so that the Department and the public have adequate
information to evaluate the discharges. If McAlpine does not make that disclosure, any discharge
of these chemicals is illegal and subject to agency or citizen enforcement. Once McAlpine makes
that disclosure, the agency must then evaluate available treatment technologies and impose limits
that ensure compliance with water quality standards. Additionally, the Department should
impose conditions that require McAlpine to update its industrial user survey to include PFAS and
1,4-dioxane. Because the draft permit fails to meet these requirements, it should be withdrawn.
Thank you for considering these comments. Please contact me at 919-967-1450 or
[e-mail] if you have any questions regarding this letter.

Sincerely,

Hannah M. Nelson
SOUTHERN ENVIRONMENTAL LAW CENTER
601 W. Rosemary Street, Suite 220
Chapel Hill, NC 27516

92 U.S. Env’t Prot. Agency, EPA Model Pretreatment Ordinance, at 24 (Jan. 2007), available at
https://www3.epa.gov/npdes/pubs/pretreatment_model_suo.pdf.
93 General Pretreatment Regulations for Existing and New Sources, 52 Fed. Reg. 1586, 1590 (Jan. 14, 1987)
(codified at 40 C.F.R. § 403).
1
Coco, Nick A
From:Cantrell, Wade <[e-mail]>
Sent:Thursday, April 6, 2023 12:13 PM
To:Coco, Nick A
Cc:Green, Brenda A.; Waldner, Susan; Montebello, Michael J; Varlik, Banu; Behm, Pamela
Subject:Re: [External] Re: E. coli in NC permits
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Report Spam. 

Thanks Nick! 

Wade Cantrell
303d, Modeling & TMDL Section Manager
Division of Water Quality - Bureau of Water
S.C. Dept. of Health & Environmental Control
Office: [phone]
Connect: www.scdhec.gov Facebook Twitter
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From: Coco, Nick A <[e-mail]> 
Sent: Thursday, April 6, 2023 10:31 AM 
To: Cantrell, Wade <[e-mail]> 
Cc: Green, Brenda A. <[e-mail]>; Waldner, Susan <[e-mail]>; Montebello, Michael J 
<[e-mail]>; Varlik, Banu <[e-mail]>; [e-mail] 
<[e-mail]> 
Subject: RE: [External] Re: E. coli in NC permits  

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*** 
Hi Wade, 

Thank you so much for taking the time to look into this and check that the permit wouldn’t cause these downstream 
concerns. I will proceed with our process and will make sure to send SCDHEC a copy of the draft permit for your review 
and comment. 

Thanks again, 
Nick Coco, PE (he/him/his) 
Engineer III  
NPDES Municipal Permitting Unit 
NC DEQ / Division of Water Resources / Water Quality Permitting 
Office: (919) 707‐3609 
[e-mail]  
Physical Address: 512 North Salisbury St.,Raleigh, NC, 27604 
Mailing Address: 1617 Mail Service Center, Raleigh, NC, 27699‐1617 
2

From: Cantrell, Wade <[e-mail]>  
Sent: Wednesday, April 5, 2023 12:47 PM 
To: Coco, Nick A <[e-mail]> 
Cc: Green, Brenda A. <[e-mail]>; Waldner, Susan <[e-mail]>; Montebello, Michael J 
<[e-mail]>; Varlik, Banu <[e-mail]>; Behm, Pamela <[e-mail]> 
Subject: Re: [External] Re: E. coli in NC permits 

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Nick‐ 

Thanks for the opportunity to provide feedback.  After reviewing permit limits, the NC TMDL and the actual 
effluent data (summarized in the tables below), we do not object to the draft limits for the 3 NC facilities 
based on fecal coliform bacteria as the indicator.  This conclusion is based on (1) the general consistency of of 
SC and NC permit limits which account for the relationship between fecal coliform and E coli as determined in 
the DHEC Pathogen Indicator Study circa 2009 and (2) the extensive effluent data record showing a de 
minimus number of samples greater than 400 fecal coliform. 

It is possible that new information or comments arising during development of the SC E coli TMDL could cause 
another look, but based on what we know now, we do not believe any changes to proposed bacteria limits are 
necessary at this time.   

Thanks! 
Wade           

3

Wade Cantrell
303d, Modeling & TMDL Section Manager
Division of Water Quality - Bureau of Water
S.C. Dept. of Health & Environmental Control
Office: [phone]
Connect: www.scdhec.gov Facebook Twitter 
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From: Coco, Nick A <[e-mail]> 
Sent: Tuesday, March 14, 2023 1:12 PM 
To: Cantrell, Wade <[e-mail]> 
Cc: Green, Brenda A. <[e-mail]>; Waldner, Susan <[e-mail]>; Montebello, Michael J 
4
<[e-mail]> 
Subject: RE: [External] Re: E. coli in NC permits  

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*** 
Hi Wade, 

Sorry – took a second to dig it up. The attached should be the FC TMDL. These 3 are already drafted, and one of the 
internal review comments was to check with you regarding e. coli, so I’d say a response as soon as is reasonable on your 
end, considering your own workloads and responsibilities. Is end of March too soon? 

Thanks, 
Nick Coco, PE (he/him/his) 
Engineer III  
NPDES Municipal Permitting Unit 
NC DEQ / Division of Water Resources / Water Quality Permitting 
Office: (919) 707‐3609 
[e-mail]  
**Email is preferred but I am available to talk by via Microsoft Teams** 

Physical Address: 512 North Salisbury St.,Raleigh, NC, 27604 
Mailing Address: 1617 Mail Service Center, Raleigh, NC, 27699‐1617 

From: Cantrell, Wade <[e-mail]>  
Sent: Tuesday, March 14, 2023 12:21 PM 
To: Coco, Nick A <[e-mail]> 
Cc: Green, Brenda A. <[e-mail]>; Waldner, Susan <[e-mail]>; Montebello, Michael J 
<[e-mail]> 
Subject: Re: [External] Re: E. coli in NC permits 

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Report Spam. 

Great, thanks Nick.  Last thing, just if you have a link to NC FC TMDL would be helpful, if not we might already 
have it or can dig around. 

We are ramping up an E. coli TMDL for our side of Sugar Creek and good to think about these questions 
now.  I'd like for our TMDL project manager to take a look.  When do you need response? 

5
Wade Cantrell
303d, Modeling & TMDL Section Manager
Division of Water Quality - Bureau of Water
S.C. Dept. of Health & Environmental Control
Office: [phone]
Connect: www.scdhec.gov Facebook Twitter 
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From: Coco, Nick A <[e-mail]> 
Sent: Tuesday, March 14, 2023 12:11 PM 
To: Cantrell, Wade <[e-mail]> 
Cc: Green, Brenda A. <[e-mail]>; Waldner, Susan <[e-mail]>; Montebello, Michael J 
<[e-mail]> 
Subject: RE: [External] Re: E. coli in NC permits  

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*** 
Hi Wade, 

Please see attached for the data requested. I’ve included effluent and instream data (for fecal – maintained in the 
McAlpine Creek DMR for all sites) for NC0024970 McAlpine Creek WWMF, NC0024945 Irwin Creek WWTP and 
NC0024937 Sugar Creek WWTP. While the McAlpine Creek WWMF is the permit in question, each of the three facilities 
are owned and operated by Charlotte Water, are currently in the renewal drafting process and discharge just above the 
state border in about the same area. I figured offering more info couldn’t hurt. Feel free to ignore extraneous info. 
Please let me know if there is anything else you need. 

Thanks again for looking into this, 
Nick Coco, PE (he/him/his) 
Engineer III  
NPDES Municipal Permitting Unit 
NC DEQ / Division of Water Resources / Water Quality Permitting 
Office: (919) 707‐3609 
[e-mail]  
**Email is preferred but I am available to talk by via Microsoft Teams** 

Physical Address: 512 North Salisbury St.,Raleigh, NC, 27604 
Mailing Address: 1617 Mail Service Center, Raleigh, NC, 27699‐1617 

6
From: Cantrell, Wade <[e-mail]>  
Sent: Tuesday, March 14, 2023 11:50 AM 
To: Coco, Nick A <[e-mail]> 
Cc: Green, Brenda A. <[e-mail]>; Waldner, Susan <[e-mail]> 
Subject: [External] Re: E. coli in NC permits 

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Report Spam. 

Hi Nick‐ 
Brenda asked us (303d/TMDL/WLA section) to look at your question below.  Thanks for reaching out.  Would it 
be possible to get DMR data for this facility, say flow and bacteria going back to 2000 or as available in your 
database?  Also, do you have a link for the NC FC TMDL?  Would like to check a couple of things and give 
feedback asap. 
Thanks, 
Wade   

Wade Cantrell
303d, Modeling & TMDL Section Manager
Division of Water Quality - Bureau of Water
S.C. Dept. of Health & Environmental Control
Office: [phone]
Connect: www.scdhec.gov Facebook Twitter 
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From: Green, Brenda A. <[e-mail]> 
Sent: Monday, March 13, 2023 1:46 PM 
To: Cantrell, Wade <[e-mail]> 
Subject: Fwd: E. coli in NC permits  

Will you take a look at the original question from NC and give me any feedback? Thanks! 

Get Outlook for iOS 
From: Siddiqui, Mohammed <[e-mail]> 
Sent: Thursday, March 9, 2023 12:14:29 PM 
To: Green, Brenda A. <[e-mail]>; Clarke, Shawn <[e-mail]> 
Subject: Re: E. coli in NC permits  

McAlpine creek south of the border is impaired 
Use: AL/Rec 
Cause: Bio/Ecoli 

Also there is a d/s intake S29106 
and a little further down is S12101 

Sohail Siddiqui, P.E.
Environmental Engineer, Domestic Wastewater Permitting Section, Bureau of Water
S.C. Dept. of Health & Environmental Control
7
Office: [phone]
Fax: [phone]
Connect: www.scdhec.gov Facebook Twitter 
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From: Green, Brenda A. <[e-mail]> 
Sent: Thursday, March 9, 2023 10:43 AM 
To: Clarke, Shawn <[e-mail]> 
Cc: Siddiqui, Mohammed <[e-mail]> 
Subject: Fw: E. coli in NC permits  

This is one I didn't see.  I think we would want e.Coli limits since they are close. 

Brenda Green  
Manager, Domestic Wastewater Permitting Section  
Bureau of Water 
S.C. Dept. of Health & Environmental Control
Office: [phone]
Fax: [phone]
Connect: www.scdhec.gov Facebook Twitter 
To help protect your priv acy, Microsoft Office prevented automatic download of this picture from the Internet.

From: Coco, Nick A <[e-mail]> 
Sent: Wednesday, March 1, 2023 2:19 PM 
To: Green, Brenda A. <[e-mail]> 
Cc: Montebello, Michael J <[e-mail]> 
Subject: RE: E. coli in NC permits  

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*** 
Hi Brenda, 

I was wondering if you were able to give this email some thought. I’ll be sending you a copy of the draft permit as well 
once it makes it to that stage, but wanted to make sure I addressed this particular item before sending it out for 
comment. 

Thanks, 
Nick Coco, PE (he/him/his) 
Engineer III  
NPDES Municipal Permitting Unit 
NC DEQ / Division of Water Resources / Water Quality Permitting 
Office: (919) 707‐3609 
[e-mail]  
**Email is preferred but I am available to talk by via Microsoft Teams** 

8
Physical Address: 512 North Salisbury St.,Raleigh, NC, 27604 
Mailing Address: 1617 Mail Service Center, Raleigh, NC, 27699‐1617 

From: Coco, Nick A  
Sent: Wednesday, February 22, 2023 9:58 AM 
To: Green, Brenda A. <[e-mail]> 
Cc: Montebello, Michael J <[e-mail]> 
Subject: E. coli in NC permits 

Hi Brenda, 

I hope you’re doing well. 

I’m currently working through the renewal of the McAlpine Creek WWMF NPDES permit NC0024970. This is a major 
discharger (64.0 MGD permitted flow) which discharges above the NC/SC border. As you may know, this particular 
facility is subject to a fecal coliform TMDL, which requires the facility to meet a daily maximum limitation of 1000/100mL 
in addition to the standard MA of 200/100mL and WA of 400/100mL. In the peer review process, it was brought to my 
attention that SC has E.coli standards to uphold as well and it was suggested I reach out to you to either ensure that the 
fecal coliform TMDL is protective of the SC water uses or ask what type of E.coli considerations should be made for this 
discharge. Would you be able to share some insight here? 

Thanks so much in advance for your time and any guidance you can provide. 

Best, 
Nick Coco, PE (he/him/his) 
Engineer III  
NPDES Municipal Permitting Unit 
NC DEQ / Division of Water Resources / Water Quality Permitting 
Office: (919) 707‐3609 
[e-mail]  
**Email is preferred but I am available to talk by via Microsoft Teams** 

Physical Address: 512 North Salisbury St.,Raleigh, NC, 27604 
Mailing Address: 1617 Mail Service Center, Raleigh, NC, 27699‐1617 
9

1
Coco, Nick A
From:Green, Brenda A. <[e-mail]>
Sent:Monday, May 22, 2023 3:16 PM
To:Coco, Nick A
Cc:Montebello, Michael J
Subject:[External] Re: Draft Permit McAlpine Creek WWMF, NPDES Permit Number NC0024970, SIC Code
4952
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button located on your Outlook menu bar on the Home tab. 

We have no additional comments outside of what Wade Cantrell has submitted. Thanks. 

BG 

Brenda Green
Manager, Domestic Wastewater Permitting Section
Bureau of Water
S.C. Dept. of Health & Environmental Control
Office: [phone]
Fax: [phone]
Connect: www.scdhec.gov Facebook Twitter
To help protect yMicrosoft Office pautomatic downlopicture from the

From: Coco, Nick A <[e-mail]> 
Sent: Friday, May 19, 2023 8:59 AM 
To: Green, Brenda A. <[e-mail]> 
Cc: Montebello, Michael J <[e-mail]> 
Subject: Draft Permit McAlpine Creek WWMF, NPDES Permit Number NC0024970, SIC Code 4952  

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Hey Brenda, 

I hope all is well 

Please see the following links to review the draft permit and cover letter and draft fact sheet for NPDES permit 
NC0024970 for the McAlpine Creek WWMF. I have also provided a link to the NPDES Standard Conditions for your 
reference. SCDHEC has a 30‐day period ending on 6/19/2023 to comment, ask questions, or request an extension to 
review this draft permit. Please contact me with any comments you might have. 

Draft Permit:  https://edocs.deq.nc.gov/WaterResources/DocView.aspx?id=2789035&dbid=0&repo=WaterResources 
NPDES Standard Conditions:  https://bit.ly/3k5NFaL 
Draft Fact Sheet: https://edocs.deq.nc.gov/WaterResources/DocView.aspx?id=2801459&dbid=0&repo=WaterResources 

Thanks, and have a nice day. 

Best, 
2
Nick Coco, PE (he/him/his) 
Engineer III  
NPDES Municipal Permitting Unit 
NC DEQ / Division of Water Resources / Water Quality Permitting 
Office: (919) 707‐3609 
[e-mail]  
Physical Address: 512 North Salisbury St.,Raleigh, NC, 27604 
Mailing Address: 1617 Mail Service Center, Raleigh, NC, 27699‐1617 

Email correspondence to and from this address may be subject to the North Carolina Public Records Law and may be disclosed to third parties by an authorized
state official. 
Permit No. NC0024970
Page 1 of 4

NPDES Implementation of Instream Dissolved Metals Standards – Freshwater Standards
The NC 2007-2015 Water Quality Standard (WQS) Triennial Review was approved by the NC
Environmental Management Commission (EMC) on November 13, 2014. The US EPA subsequently
approved the WQS revisions on April 6, 2016, with some exceptions. Therefore, metal limits in draft
permits out to public notice after April 6, 2016 must be calculated to protect the new standards - as
approved.
Table 1. NC Dissolved Metals Water Quality Standards/Aquatic Life Protection
Parameter Acute FW, µg/l
(Dissolved)
Chronic FW, µg/l
(Dissolved)
Acute SW, µg/l
(Dissolved)
Chronic SW, µg/l
(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 standard
3. Only the aquatic life standards listed above are expressed in dissolved form. Aquatic life
standards for Mercury and selenium are still expressed as Total Recoverable Metals due to
bioaccumulative concerns (as are all human health standards for all metals). It is still necessary
to evaluate total recoverable aquatic life and human health standards listed in 15A NCAC
2B.0200 (e.g., arsenic at 10 µg/l for human health protection; cyanide at 5 µg/L and fluoride at
1.8 mg/L for aquatic life protection).

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, µg/l
Cadmium, Acute WER*{1.136672-[ln hardness](0.041838)} ∙ e^{0.9151 [ln hardness]-3.1485}
Cadmium, Acute Trout waters WER*{1.136672-[ln hardness](0.041838)} ∙ e^{0.9151[ln hardness]-3.6236}
Cadmium, Chronic WER*{1.101672-[ln hardness](0.041838)} ∙ e^{0.7998[ln hardness]-4.4451}
Chromium III, Acute WER*0.316 ∙ e^{0.8190[ln hardness]+3.7256}
Chromium III, Chronic WER*0.860 ∙ e^{0.8190[ln hardness]+0.6848}
Copper, Acute WER*0.960 ∙ e^{0.9422[ln hardness]-1.700}
Copper, Chronic WER*0.960 ∙ e^{0.8545[ln hardness]-1.702}
Lead, Acute WER*{1.46203-[ln hardness](0.145712)} ∙ e^{1.273[ln hardness]-1.460}
Lead, Chronic WER*{1.46203-[ln hardness](0.145712)} ∙ e^{1.273[ln hardness]-4.705}
Nickel, Acute WER*0.998 ∙ e^{0.8460[ln hardness]+2.255}
Nickel, Chronic WER*0.997 ∙ e^{0.8460[ln hardness]+0.0584}
Permit No. NC0024970
Page 2 of 4

Silver, Acute WER*0.85 ∙ e^{1.72[ln hardness]-6.59}
Silver, Chronic Not applicable
Zinc, Acute WER*0.978 ∙ e^{0.8473[ln hardness]+0.884}
Zinc, Chronic WER*0.986 ∙ e^{0.8473[ln hardness]+0.884}

General Information on the Reasonable Potential Analysis (RPA)
The RPA process itself did not change as the result of the new metals standards. However, application of
the dissolved and hardness-dependent standards requires additional consideration in order to establish the
numeric standard for each metal of concern of each individual discharge.
The hardness-based standards require some knowledge of the effluent and instream (upstream) hardness
and so must be calculated case-by-case for each discharge.
Metals limits must be expressed as ‘total recoverable’ metals in accordance with 40 CFR 122.45(c). The
discharge-specific standards must be converted to the equivalent total values for use in the RPA
calculations. We will generally rely on default translator values developed for each metal (more on that
below), but it is also possible to consider case-specific translators developed in accordance with
established methodology.

RPA Permitting Guidance/WQBELs for Hardness-Dependent Metals - Freshwater
The RPA is designed to predict the maximum likely effluent concentrations for each metal of concern,
based on recent effluent data, and calculate the allowable effluent concentrations, based on applicable
standards and the critical low-flow values for the receiving stream.
If the maximum predicted value is greater than the maximum allowed value (chronic or acute), the
discharge has reasonable potential to exceed the standard, which warrants a permit limit in most cases. 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, 7Q10 (the spreadsheet automatically calculates
the 1Q10 using the formula 1Q10 = 0.843 (s7Q10, cfs) 0.993
• Effluent hardness and upstream hardness, site-specific data is preferred
• Permitted flow
• Receiving stream classification

2. In order to establish the numeric standard for each hardness-dependent metal of concern and for
each individual discharge, the Permit Writer must first determine what effluent and instream
(upstream) hardness values to use in the equations.

The permit writer reviews DMR’s, Effluent Pollutant Scans, and Toxicity Test results for any
hardness data and contacts 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 (CaCO3 or (Ca + Mg)). Minimum and maximum limits on the
hardness value used for water quality calculations are 25 mg/L and 400 mg/L, respectively.

If the use of a default hardness value results in a hardness-dependent metal showing reasonable
potential, the permit writer contacts the Permittee and requests 5 site-specific effluent and
upstream hardness samples over a period of one week. The RPA is rerun using the new data.

Permit No. NC0024970
Page 3 of 4

The overall hardness value used in the water quality calculations is calculated as follows:
Combined Hardness (chronic)
= (Permitted Flow, cfs *Avg. Effluent Hardness, mg/L) + (s7Q10, cfs *Avg. Upstream Hardness, mg/L)
(Permitted Flow, cfs + s7Q10, cfs)
The Combined Hardness for acute is the same but the calculation uses the 1Q10 flow.
3. The permit writer converts the numeric standard for each metal of concern to a total recoverable
metal, using the EPA Default Partition Coefficients (DPCs) or site-specific translators, if any
have been developed using federally approved methodology.

4. The numeric standard for each metal of concern is divided by the default partition coefficient (or
site-specific translator) to obtain a Total Recoverable Metal at ambient conditions.

In some cases, where an EPA default partition coefficient translator does not exist (ie. silver), the
dissolved numeric standard for each metal of concern is divided by the EPA conversion factor to
obtain a Total Recoverable Metal at ambient conditions. This method presumes that the metal is
dissolved to the same extent as it was during EPA’s criteria development for metals. For more
information on conversion factors see the June, 1996 EPA Translator Guidance Document.

5. The RPA spreadsheet uses a mass balance equation to determine the total allowable concentration
(permit limits) for each pollutant using the following equation:

Ca = (s7Q10 + Qw) (Cwqs) – (s7Q10) (Cb)
Qw
Where: Ca = allowable effluent concentration (µg/L or mg/L)
Cwqs = NC Water Quality Standard or federal criteria (µg/L or mg/L)
Cb = background concentration: assume zero for all toxicants except NH3* (µg/L or mg/L)
Qw = permitted effluent flow (cfs, match s7Q10)
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 (cfs)
* Discussions are on-going with EPA on how best to address background concentrations

Flows other than s7Q10 may be incorporated as applicable:
1Q10 = used in the equation to protect aquatic life from acute toxicity
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 + { [Kpo] [ss(1+a)] [10-6] }

Where:
ss = in-stream suspended solids concentration [mg/l], minimum of 10 mg/L used,
and
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.

Permit No. NC0024970
Page 4 of 4

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

6. The permit writer enters the most recent 2-3 years of effluent data for each pollutant of concern.
Data entered must have been taken within four and one-half years prior to the date of the permit
application (40 CFR 122.21). The RPA spreadsheet estimates the 95th percentile upper
concentration of each pollutant. The Predicted Max concentrations are compared to the Total
allowable concentrations to determine if a permit limit is necessary. If the predicted max exceeds
the acute or chronic Total allowable concentrations, the discharge is considered to show
reasonable potential to violate the water quality standard, and a permit limit (Total allowable
concentration) is included in the permit in accordance with the U.S. EPA Technical Support
Document for Water Quality-Based Toxics Control published in 1991.

7. When appropriate, permit writers develop facility specific compliance schedules in accordance
with the EPA Headquarters Memo dated May 10, 2007 from James Hanlon to Alexis Strauss on
40 CFR 122.47 Compliance Schedule Requirements.

8. The Total Chromium NC WQS was removed and replaced with trivalent chromium and
hexavalent chromium Water Quality Standards. As a cost savings measure, total chromium data
results may be used as a conservative surrogate in cases where there are no analytical results
based on chromium III or VI. In these cases, the projected maximum concentration (95th %) for
total chromium will be compared against water quality standards for chromium III and
chromium VI.

9. Effluent hardness sampling and instream hardness sampling, upstream of the discharge, are
inserted into all permits with facilities monitoring for hardness-dependent metals to ensure the
accuracy of the permit limits and 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 (Data Source)
Average Effluent Hardness (mg/L)
[Total as, CaCO3 or (Ca+Mg)]
152.6 Average from January 2018 to
August 2022 samples
Average Upstream Hardness (mg/L)
[Total as, CaCO3 or (Ca+Mg)]
80.7 Average from January 2018 to
August 2022 samples
7Q10 summer (cfs) 2.0 Historical; Previous Fact Sheet
1Q10 (cfs) 1.68 Calculated in RPA
Permitted Flow (MGD) 64.0 NPDES Files

Date: _____12/19/2022________________________

Permit Writer: ______Nick Coco________________
REQUIRED DATA ENTRY
Name WQS Type Chronic Modifier Acute PQL Units
Facility Name McAlpine Creek WWMF Par01 Arsenic Aquactic Life C 150 FW 340 ug/L
WWTP/WTP Class IV Par02 Arsenic Human Health
Water Supply C 10 HH/WS N/A ug/L
NPDES Permit NC0024970 Par03 Beryllium Aquatic Life NC 6.5 FW 65 ug/L
Outfall 001 Par04 Cadmium Aquatic Life NC 2.2941 FW 15.5700 ug/L
Flow, Qw (MGD)64.000 Par05 Chlorides Aquatic Life NC 230 FW mg/L
Receiving Stream McAlpine Creek Par06 Chlorinated Phenolic Compounds Water Supply NC 1 A ug/L
HUC Number 03050103 Par07 Total Phenolic Compounds Aquatic Life NC 300 A ug/L
Stream Class Par08 Chromium III Aquatic Life NC 513.9885 FW 3956.1300 ug/L
Par09 Chromium VI Aquatic Life NC 11 FW 16 µg/L
7Q10s (cfs)2.00 Par10 Chromium, Total Aquatic Life NC N/A FW N/A µg/L
7Q10w (cfs)10.00 Par11 Copper Aquatic Life NC 36.6743 FW 57.1443 ug/L
30Q2 (cfs)13.50 Par12 Cyanide Aquatic Life NC 5 FW 22 10 ug/L
QA (cfs)62.40 Par13 Fluoride Aquatic Life NC 1,800 FW ug/L
1Q10s (cfs)1.68 Par14 Lead Aquatic Life NC 21.3941 FW 549.8819 ug/L
Effluent Hardness 152.59 mg/L (Avg)Par15 Mercury Aquatic Life NC 12 FW 0.5 ng/L
Upstream Hardness 80.65 mg/L (Avg)Par16 Molybdenum Human Health NC 2000 HH ug/L
Combined Hardness Chronic 151.16 mg/L Par17 Nickel Aquatic Life NC 170.6343 FW 1538.2117 µg/L
Combined Hardness Acute 151.39 mg/L Par18 Nickel Water Supply NC 25.0000 WS N/A µg/L
Data Source(s)Par19 Selenium Aquatic Life NC 5 FW 56 ug/L
Par20 Silver Aquatic Life NC 0.06 FW 6.5641 ug/L
Par21 Zinc Aquatic Life NC 582.1902 FW 578.1905 ug/L
Par22 Dichlorobromomethane Human Health C 17 HH µg/L
Par23
Par24
Follow directions for data entry. In some cases a
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.
To appy a Model IWC %: Once the
"Flow, Qw (MGD)" and and the
"CHRONIC DILUTION FACTOR =
" values are entered, the 7Q10s
(cfs) flow is calculated and
displayed. Enter the calculated
"7Q10s (cfs)" flow value in Table 1.
Table 1. Project Information Table 2. Parameters of Concern
Freshwater RPA - 95% Probability/95% Confidence Using Metal Translators
MAXIMUM DATA POINTS = 58
C
CHECK IF HQW OR ORW WQS
CHECK TO APPLY MODEL
Apply WS Hardness WQC
24970 rpa, input
9/14/2022
REASONABLE POTENTIAL ANALYSIS
H1 H2
Effluent Hardness Upstream Hardness
Date Data BDL=1/2DL Results Date Data BDL=1/2DL Results
1 2/20/2018 150 150 Std Dev.15.3966 1 1/16/2018 66 66 Std Dev.18.8996
2 3/20/2018 140 140 Mean 152.5862 2 2/21/2018 94 94 Mean 80.6545
3 4/17/2018 150 150 C.V.0.1009 3 3/14/2018 73 73 C.V.0.2343
4 5/22/2018 160 160 n 58 4 4/11/2018 94 94 n 55
5 6/19/2018 170 170 10th Per value 137.00 mg/L 5 5/14/2018 110 110 10th Per value 59.80 mg/L
6 7/24/2018 130 130 Average Value =152.59 mg/L 6 6/13/2018 92 92 Average Value =80.65 mg/L
7 8/21/2018 150 150 Max. Value 180.00 mg/L 7 7/23/2018 120 120 Max. Value 120.00 mg/L
8 9/12/2018 160 160 8 8/6/2018 59 59
9 9/25/2018 150 150 9 9/5/2018 75 75
10 10/16/2018 140 140 10 10/15/2018 74 74
11 11/20/2018 140 140 11 11/19/2018 69 69
12 12/18/2018 130 130 12 12/13/2018 68 68
13 1/14/2019 120 120 13 1/14/2019 59 59
14 2/9/2019 160 160 14 2/14/2019 65 65
15 3/10/2019 140 140 15 3/19/2019 86 86
16 4/8/2019 140 140 16 4/16/2019 73 73
17 5/7/2019 140 140 17 5/21/2019 110 110
18 6/5/2019 160 160 18 6/17/2019 73 73
19 7/11/2019 160 160 19 7/18/2019 90 90
20 8/9/2019 180 180 20 8/7/2019 61 61
21 9/7/2019 170 170 21 9/12/2019 110 110
22 10/6/2019 150 150 22 10/8/2019 120 120
23 11/18/2019 170 170 23 11/14/2019 50 50
24 12/4/2019 180 180 24 12/19/2019 67 67
25 12/10/2019 170 170 25 1/9/2020 94 94
26 1/8/2020 160 160 26 2/4/2020 75 75
27 2/6/2020 170 170 27 3/16/2020 100 100
28 3/6/2020 170 170 28 4/6/2020 110 110
29 3/11/2020 170 170 29 5/11/2020 100 100
30 4/4/2020 160 160 30 6/1/2020 75 75
31 5/10/2020 140 140 31 7/7/2020 91 91
32 6/8/2020 140 140 32 8/3/2020 76 76
33 7/14/2020 170 170 33 9/15/2020 84 84
34 8/5/2020 150 150 34 10/5/2020 91 91
35 9/17/2020 160 160 35 11/2/2020 63 63
36 10/9/2020 140 140 36 12/8/2020 74 74
37 11/7/2020 130 130 37 1/11/2021 71 71
38 12/6/2020 140 140 38 2/3/2021 77 77
39 1/11/2021 120 120 39 3/8/2021 92 92
40 2/9/2021 120 120 40 4/12/2021 87 87
41 3/10/2021 140 140 41 5/17/2021 91 91
42 4/8/2021 150 150 42 6/14/2021 74 74
43 5/14/2021 160 160 43 7/6/2021 68 68
44 6/5/2021 160 160 44 8/9/2021 92 92
45 6/9/2021 140 140 45 9/7/2021 78 78
46 7/11/2021 170 170 46 10/4/2021 110 110
47 8/16/2021 160 160 47 11/9/2021 95 95
48 9/14/2021 160 160 48 12/14/2021 63 63
49 10/13/2021 150 150 49 1/19/2022 56 56
50 11/18/2021 140 140 50 2/9/2022 56 56
51 12/17/2021 180 180 51 3/2/2022 66 66
52 1/8/2022 160 160 52 4/13/2022 85 85
53 2/6/2022 160 160 53 5/9/2022 70 70
54 3/7/2022 150 150 54 6/1/2022 91 91
55 4/5/2022 140 140 55 7/20/2022 23 23
56 5/11/2022 170 170 56
57 6/9/2022 170 170 57
58 7/22/2022 140 140 58
Use "PASTE SPECIAL-
Values" then "COPY"
. Maximum data
points = 58
Use "PASTE SPECIAL-
Values" then "COPY"
. Maximum data
points = 58
- 1 -
24970 rpa, data
9/14/2022
REASONABLE POTENTIAL ANALYSIS
Par01 & Par02
Arsenic
Date Data BDL=1/2DL Results
1 8/24/2021 <5 2.5 Std Dev.0.0000
2 8/31/2021 <5 2.5 Mean 2.5000
3 9/8/2021 <5 2.5 C.V.0.0000
4 9/14/2021 <5 2.5 n 58
5 9/21/2021 <5 2.5
6 9/28/2021 <5 2.5 Mult Factor =1.00
7 10/5/2021 <5 2.5 Max. Value 2.5 ug/L
8 10/12/2021 <5 2.5 Max. Pred Cw 2.5 ug/L
9 10/13/2021 <5 2.5
10 10/19/2021 <5 2.5
11 10/26/2021 <5 2.5
12 11/2/2021 <5 2.5
13 11/9/2021 <5 2.5
14 11/16/2021 <5 2.5
15 11/18/2021 <5 2.5
16 11/23/2021 <5 2.5
17 11/30/2021 <5 2.5
18 12/7/2021 <5 2.5
19 12/14/2021 <5 2.5
20 12/17/2021 <5 2.5
21 12/21/2021 <5 2.5
22 12/29/2021 <5 2.5
23 1/4/2022 <5 2.5
24 1/8/2022 <5 2.5
25 1/11/2022 <5 2.5
26 1/19/2022 <5 2.5
27 1/25/2022 <5 2.5
28 2/1/2022 <5 2.5
29 2/6/2022 <5 2.5
30 2/8/2022 <5 2.5
31 2/15/2022 <5 2.5
32 2/22/2022 <5 2.5
33 3/1/2022 <5 2.5
34 3/7/2022 <5 2.5
35 3/9/2022 <5 2.5
36 3/15/2022 <5 2.5
37 3/22/2022 <5 2.5
38 3/29/2022 <5 2.5
39 4/5/2022 <5 2.5
40 4/12/2022 <5 2.5
41 4/19/2022 <5 2.5
42 4/26/2022 <5 2.5
43 5/3/2022 <5 2.5
44 5/10/2022 <5 2.5
45 5/11/2022 <5 2.5
46 5/17/2022 <5 2.5
47 5/24/2022 <5 2.5
48 6/1/2022 <5 2.5
49 6/7/2022 <5 2.5
50 6/9/2022 <5 2.5
51 6/14/2022 <5 2.5
52 6/21/2022 <5 2.5
53 6/28/2022 <5 2.5
54 7/6/2022 <5 2.5
55 7/12/2022 <5 2.5
56 7/19/2022 <5 2.5
57 7/22/2022 <5 2.5
58 7/26/2022 <5 2.5
Use "PASTE SPECIAL-
Values" then "COPY"
. Maximum data
points = 58
- 2 -
24970 rpa, data
9/14/2022
REASONABLE POTENTIAL ANALYSIS
Par03 Par04
Beryllium Cadmium
Date Data BDL=1/2DL Results Date Data BDL=1/2DL Results
1 9/12/2018 <2 1 Std Dev.0.0000 1 8/24/2021 <0.5 0.25 Std Dev.0.0000
2 12/4/2019 <2 1 Mean 1.0000 2 8/31/2021 <0.5 0.25 Mean 0.2500
3 3/11/2020 <2 1 C.V. (default)0.6000 3 9/8/2021 <0.5 0.25 C.V.0.0000
4 6/9/2021 <2 1 n 4 4 9/14/2021 <0.5 0.25 n 58
5 5 9/21/2021 <0.5 0.25
6 Mult Factor =2.59 6 9/28/2021 <0.5 0.25 Mult Factor =1.00
7 Max. Value 1.00 ug/L 7 10/5/2021 <0.5 0.25 Max. Value 0.250 ug/L
8 Max. Pred Cw 2.59 ug/L 8 10/12/2021 <0.5 0.25 Max. Pred Cw 0.250 ug/L
9 9 10/13/2021 <0.5 0.25
10 10 10/19/2021 <0.5 0.25
11 11 10/26/2021 <0.5 0.25
12 12 11/2/2021 <0.5 0.25
13 13 11/9/2021 <0.5 0.25
14 14 11/16/2021 <0.5 0.25
15 15 11/18/2021 <0.5 0.25
16 16 11/23/2021 <0.5 0.25
17 17 11/30/2021 <0.5 0.25
18 18 12/7/2021 <0.5 0.25
19 19 12/14/2021 <0.5 0.25
20 20 12/17/2021 <0.5 0.25
21 21 12/21/2021 <0.5 0.25
22 22 12/29/2021 <0.5 0.25
23 23 1/4/2022 <0.5 0.25
24 24 1/8/2022 <0.5 0.25
25 25 1/11/2022 <0.5 0.25
26 26 1/19/2022 <0.5 0.25
27 27 1/25/2022 <0.5 0.25
28 28 2/1/2022 <0.5 0.25
29 29 2/6/2022 <0.5 0.25
30 30 2/8/2022 <0.5 0.25
31 31 2/15/2022 <0.5 0.25
32 32 2/22/2022 <0.5 0.25
33 33 3/1/2022 <0.5 0.25
34 34 3/7/2022 <0.5 0.25
35 35 3/9/2022 <0.5 0.25
36 36 3/15/2022 <0.5 0.25
37 37 3/22/2022 <0.5 0.25
38 38 3/29/2022 <0.5 0.25
39 39 4/5/2022 <0.5 0.25
40 40 4/12/2022 <0.5 0.25
41 41 4/19/2022 <0.5 0.25
42 42 4/26/2022 <0.5 0.25
43 43 5/3/2022 <0.5 0.25
44 44 5/10/2022 <0.5 0.25
45 45 5/11/2022 <0.5 0.25
46 46 5/17/2022 <0.5 0.25
47 47 5/24/2022 <0.5 0.25
48 48 6/1/2022 <0.5 0.25
49 49 6/7/2022 <0.5 0.25
50 50 6/9/2022 <0.5 0.25
51 51 6/14/2022 <0.5 0.25
52 52 6/21/2022 <0.5 0.25
53 53 6/28/2022 <0.5 0.25
54 54 7/6/2022 <0.5 0.25
55 55 7/12/2022 <0.5 0.25
56 56 7/19/2022 <0.5 0.25
57 57 7/22/2022 <0.5 0.25
58 58 7/26/2022 <0.5 0.25
Use "PASTE SPECIAL-
Values" then "COPY"
. Maximum data
points = 58
Use "PASTE SPECIAL-
Values" then "COPY"
. Maximum data
points = 58
- 3 -
24970 rpa, data
9/14/2022
REASONABLE POTENTIAL ANALYSIS
Par07 Par10
Total Phenolic Compounds Chromium, Total
Date Data BDL=1/2DL Results Date Data BDL=1/2DL Results
1 1/17/2018 <50 25 Std Dev.9.1140 1 8/24/2021 <5 2.5 Std Dev.0.0000
2 3/14/2018 <50 25 Mean 27.2581 2 8/31/2021 <5 2.5 Mean 2.5000
3 5/14/2018 70 70 C.V.0.3344 3 9/8/2021 <5 2.5 C.V.0.0000
4 7/9/2018 <50 25 n 31 4 9/14/2021 <5 2.5 n 58
5 9/12/2018 <50 25 5 9/21/2021 <5 2.5
6 11/13/2018 <50 25 Mult Factor =1.11 6 9/28/2021 <5 2.5 Mult Factor =1.00
7 1/14/2019 <50 25 Max. Value 70.0 ug/L 7 10/5/2021 <5 2.5 Max. Value 2.5 µg/L
8 3/6/2019 <50 25 Max. Pred Cw 77.7 ug/L 8 10/12/2021 <5 2.5 Max. Pred Cw 2.5 µg/L
9 5/13/2019 <50 25 9 10/13/2021 <5 2.5
10 7/8/2019 <50 25 10 10/19/2021 <5 2.5
11 9/11/2019 <50 25 11 10/26/2021 <5 2.5
12 11/12/2019 <50 25 12 11/2/2021 <5 2.5
13 12/4/2019 <50 25 13 11/9/2021 <5 2.5
14 1/6/2020 <50 25 14 11/16/2021 <5 2.5
15 3/2/2020 <50 25 15 11/18/2021 <5 2.5
16 3/11/2020 <50 25 16 11/23/2021 <5 2.5
17 5/4/2020 <50 25 17 11/30/2021 <5 2.5
18 7/6/2020 50 50 18 12/7/2021 <5 2.5
19 9/23/2020 <50 25 19 12/14/2021 <5 2.5
20 11/2/2020 <50 25 20 12/17/2021 <5 2.5
21 1/12/2021 <50 25 21 12/21/2021 <5 2.5
22 3/3/2021 <50 25 22 12/29/2021 <5 2.5
23 5/11/2021 <50 25 23 1/4/2022 <5 2.5
24 6/9/2021 <50 25 24 1/8/2022 <5 2.5
25 7/7/2021 <50 25 25 1/11/2022 <5 2.5
26 9/8/2021 <50 25 26 1/19/2022 <5 2.5
27 11/9/2021 <50 25 27 1/25/2022 <5 2.5
28 1/11/2022 <50 25 28 2/1/2022 <5 2.5
29 3/9/2022 <50 25 29 2/6/2022 <5 2.5
30 5/3/2022 <50 25 30 2/8/2022 <5 2.5
31 7/12/2022 <50 25 31 2/15/2022 <5 2.5
32 32 2/22/2022 <5 2.5
33 33 3/1/2022 <5 2.5
34 34 3/7/2022 <5 2.5
35 35 3/9/2022 <5 2.5
36 36 3/15/2022 <5 2.5
37 37 3/22/2022 <5 2.5
38 38 3/29/2022 <5 2.5
39 39 4/5/2022 <5 2.5
40 40 4/12/2022 <5 2.5
41 41 4/19/2022 <5 2.5
42 42 4/26/2022 <5 2.5
43 43 5/3/2022 <5 2.5
44 44 5/10/2022 <5 2.5
45 45 5/11/2022 <5 2.5
46 46 5/17/2022 <5 2.5
47 47 5/24/2022 <5 2.5
48 48 6/1/2022 <5 2.5
49 49 6/7/2022 <5 2.5
50 50 6/9/2022 <5 2.5
51 51 6/14/2022 <5 2.5
52 52 6/21/2022 <5 2.5
53 53 6/28/2022 <5 2.5
54 54 7/6/2022 <5 2.5
55 55 7/12/2022 <5 2.5
56 56 7/19/2022 <5 2.5
57 57 7/22/2022 <5 2.5
58 58 7/26/2022 <5 2.5
Use "PASTE SPECIAL-
Values" then "COPY"
. Maximum data
points = 58
Use "PASTE SPECIAL-
Values" then "COPY"
. Maximum data
points = 58
- 4 -
24970 rpa, data
9/14/2022
REASONABLE POTENTIAL ANALYSIS
Pa11 Par12
Copper Cyanide
Date Data BDL=1/2DL Results Date Data BDL=1/2DL Results
1 8/24/2021 3 3 Std Dev.0.3620 1 1/10/2022 <10 5 Std Dev.0.0000
2 8/31/2021 3.2 3.2 Mean 2.9741 2 1/11/2022 <10 5 Mean 5.00
3 9/8/2021 3 3 C.V.0.1217 3 1/18/2022 <10 5 C.V.0.0000
4 9/14/2021 3.5 3.5 n 58 4 1/19/2022 <10 5 n 58
5 9/21/2021 3.8 3.8 5 1/24/2022 <10 5
6 9/28/2021 3.4 3.4 Mult Factor =1.00 6 1/25/2022 <10 5 Mult Factor =1.00
7 10/5/2021 3.8 3.8 Max. Value 3.90 ug/L 7 1/31/2022 <10 5 Max. Value 5.0 ug/L
8 10/12/2021 3.1 3.1 Max. Pred Cw 3.90 ug/L 8 2/1/2022 <10 5 Max. Pred Cw 5.0 ug/L
9 10/13/2021 2.7 2.7 9 2/7/2022 <10 5
10 10/19/2021 3 3 10 2/8/2022 <10 5
11 10/26/2021 3.1 3.1 11 2/14/2022 <10 5
12 11/2/2021 2.9 2.9 12 2/15/2022 <10 5
13 11/9/2021 3.2 3.2 13 2/21/2022 <10 5
14 11/16/2021 3.4 3.4 14 2/22/2022 <10 5
15 11/18/2021 3.5 3.5 15 2/28/2022 <10 5
16 11/23/2021 3.4 3.4 16 3/1/2022 <10 5
17 11/30/2021 3.3 3.3 17 3/8/2022 <10 5
18 12/7/2021 3.1 3.1 18 3/9/2022 <10 5
19 12/14/2021 3.6 3.6 19 3/14/2022 <10 5
20 12/17/2021 2.7 2.7 20 3/15/2022 <10 5
21 12/21/2021 2.5 2.5 21 3/21/2022 <10 5
22 12/29/2021 2.6 2.6 22 3/22/2022 <10 5
23 1/4/2022 2.7 2.7 23 3/28/2022 <10 5
24 1/8/2022 2.6 2.6 24 3/29/2022 <10 5
25 1/11/2022 2.8 2.8 25 4/6/2022 <10 5
26 1/19/2022 2.8 2.8 26 4/7/2022 <10 5
27 1/25/2022 2.7 2.7 27 4/11/2022 <10 5
28 2/1/2022 3 3 28 4/12/2022 <10 5
29 2/6/2022 2.8 2.8 29 4/18/2022 <10 5
30 2/8/2022 2.8 2.8 30 4/19/2022 <10 5
31 2/15/2022 2.9 2.9 31 4/25/2022 <10 5
32 2/22/2022 2.6 2.6 32 4/26/2022 <10 5
33 3/1/2022 2.7 2.7 33 5/2/2022 <10 5
34 3/7/2022 2.6 2.6 34 5/3/2022 <10 5
35 3/9/2022 2.9 2.9 35 5/9/2022 <10 5
36 3/15/2022 3.1 3.1 36 5/12/2022 <10 5
37 3/22/2022 2.7 2.7 37 5/16/2022 <10 5
38 3/29/2022 3.2 3.2 38 5/17/2022 <10 5
39 4/5/2022 2.8 2.8 39 5/23/2022 <10 5
40 4/12/2022 3 3 40 5/24/2022 <10 5
41 4/19/2022 2.9 2.9 41 5/31/2022 <10 5
42 4/26/2022 3.2 3.2 42 6/1/2022 <10 5
43 5/3/2022 3.3 3.3 43 6/6/2022 <10 5
44 5/10/2022 3 3 44 6/7/2022 <10 5
45 5/11/2022 3.2 3.2 45 6/13/2022 <10 5
46 5/17/2022 3.1 3.1 46 6/14/2022 <10 5
47 5/24/2022 3.9 3.9 47 6/20/2022 <10 5
48 6/1/2022 2.7 2.7 48 6/21/2022 <10 5
49 6/7/2022 3 3 49 6/27/2022 <10 5
50 6/9/2022 2.8 2.8 50 6/28/2022 <10 5
51 6/14/2022 2.6 2.6 51 7/5/2022 <10 5
52 6/21/2022 2.5 2.5 52 7/6/2022 <10 5
53 6/28/2022 2.8 2.8 53 7/11/2022 <10 5
54 7/6/2022 2.7 2.7 54 7/12/2022 <10 5
55 7/12/2022 2.1 2.1 55 7/18/2022 <10 5
56 7/19/2022 3 3 56 7/19/2022 <10 5
57 7/22/2022 2.3 2.3 57 7/25/2022 <10 5
58 7/26/2022 2.9 2.9 58 7/26/2022 <10 5
Use "PASTE SPECIAL-
Values" then "COPY"
. Maximum data
points = 58
Use "PASTE SPECIAL-
Values" then "COPY"
. Maximum data
points = 58
- 5 -
24970 rpa, data
9/14/2022
REASONABLE POTENTIAL ANALYSIS
Par14 Par16
Lead Molybdenum
Date BDL=1/2DL Results Date Data BDL=1/2DL Results
1 8/24/2021 <5 2.5 Std Dev.0.0000 1 8/24/2021 <5 2.5 Std Dev.0.0000
2 8/31/2021 <5 2.5 Mean 2.5000 2 8/31/2021 <5 2.5 Mean 2.5000
3 9/8/2021 <5 2.5 C.V.0.0000 3 9/8/2021 <5 2.5 C.V.0.0000
4 9/14/2021 <5 2.5 n 58 4 9/14/2021 <5 2.5 n 58
5 9/21/2021 <5 2.5 5 9/21/2021 <5 2.5
6 9/28/2021 <5 2.5 Mult Factor =1.00 6 9/28/2021 <5 2.5 Mult Factor =1.00
7 10/5/2021 <5 2.5 Max. Value 2.500 ug/L 7 10/5/2021 <5 2.5 Max. Value 2.5 ug/L
8 10/12/2021 <5 2.5 Max. Pred Cw 2.500 ug/L 8 10/12/2021 <5 2.5 Max. Pred Cw 2.5 ug/L
9 10/13/2021 <5 2.5 9 10/13/2021 <5 2.5
10 10/19/2021 <5 2.5 10 10/19/2021 <5 2.5
11 10/26/2021 <5 2.5 11 10/26/2021 <5 2.5
12 11/2/2021 <5 2.5 12 11/2/2021 <5 2.5
13 11/9/2021 <5 2.5 13 11/9/2021 <5 2.5
14 11/16/2021 <5 2.5 14 11/16/2021 <5 2.5
15 11/18/2021 <5 2.5 15 11/18/2021 <5 2.5
16 11/23/2021 <5 2.5 16 11/23/2021 <5 2.5
17 11/30/2021 <5 2.5 17 11/30/2021 <5 2.5
18 12/7/2021 <5 2.5 18 12/7/2021 <5 2.5
19 12/14/2021 <5 2.5 19 12/14/2021 <5 2.5
20 12/17/2021 <5 2.5 20 12/17/2021 <5 2.5
21 12/21/2021 <5 2.5 21 12/21/2021 <5 2.5
22 12/29/2021 <5 2.5 22 12/29/2021 <5 2.5
23 1/4/2022 <5 2.5 23 1/4/2022 <5 2.5
24 1/8/2022 <5 2.5 24 1/8/2022 <5 2.5
25 1/11/2022 <5 2.5 25 1/11/2022 <5 2.5
26 1/19/2022 <5 2.5 26 1/19/2022 <5 2.5
27 1/25/2022 <5 2.5 27 1/25/2022 <5 2.5
28 2/1/2022 <5 2.5 28 2/1/2022 <5 2.5
29 2/6/2022 <5 2.5 29 2/6/2022 <5 2.5
30 2/8/2022 <5 2.5 30 2/8/2022 <5 2.5
31 2/15/2022 <5 2.5 31 2/15/2022 <5 2.5
32 2/22/2022 <5 2.5 32 2/22/2022 <5 2.5
33 3/1/2022 <5 2.5 33 3/1/2022 <5 2.5
34 3/7/2022 <5 2.5 34 3/7/2022 <5 2.5
35 3/9/2022 <5 2.5 35 3/9/2022 <5 2.5
36 3/15/2022 <5 2.5 36 3/15/2022 <5 2.5
37 3/22/2022 <5 2.5 37 3/22/2022 <5 2.5
38 3/29/2022 <5 2.5 38 3/29/2022 <5 2.5
39 4/5/2022 <5 2.5 39 4/5/2022 <5 2.5
40 4/12/2022 <5 2.5 40 4/12/2022 <5 2.5
41 4/19/2022 <5 2.5 41 4/19/2022 <5 2.5
42 4/26/2022 <5 2.5 42 4/26/2022 <5 2.5
43 5/3/2022 <5 2.5 43 5/3/2022 <5 2.5
44 5/10/2022 <5 2.5 44 5/10/2022 <5 2.5
45 5/11/2022 <5 2.5 45 5/11/2022 <5 2.5
46 5/17/2022 <5 2.5 46 5/17/2022 <5 2.5
47 5/24/2022 <5 2.5 47 5/24/2022 <5 2.5
48 6/1/2022 <5 2.5 48 6/1/2022 <5 2.5
49 6/7/2022 <5 2.5 49 6/7/2022 <5 2.5
50 6/9/2022 <5 2.5 50 6/9/2022 <5 2.5
51 6/14/2022 <5 2.5 51 6/14/2022 <5 2.5
52 6/21/2022 <5 2.5 52 6/21/2022 <5 2.5
53 6/28/2022 <5 2.5 53 6/28/2022 <5 2.5
54 7/6/2022 <5 2.5 54 7/6/2022 <5 2.5
55 7/12/2022 <5 2.5 55 7/12/2022 <5 2.5
56 7/19/2022 <5 2.5 56 7/19/2022 <5 2.5
57 7/22/2022 <5 2.5 57 7/22/2022 <5 2.5
58 7/26/2022 <5 2.5 58 7/26/2022 <5 2.5
Use "PASTE SPECIAL-
Values" then "COPY"
. Maximum data
points = 58
Use "PASTE SPECIAL-
Values" then "COPY"
. Maximum data
points = 58
- 6 -
24970 rpa, data
9/14/2022
REASONABLE POTENTIAL ANALYSIS
Par17 & Par18 Par19
Nickel Selenium
Date Data BDL=1/2DL Results Date Data BDL=1/2DL Results
1 8/24/2021 3.8 3.8 Std Dev.0.4937 1 8/24/2021 <5 2.5 Std Dev.0.0000
2 8/31/2021 4.1 4.1 Mean 4.2259 2 8/31/2021 <5 2.5 Mean 2.5000
3 9/8/2021 4.3 4.3 C.V.0.1168 3 9/8/2021 <5 2.5 C.V.0.0000
4 9/14/2021 4.6 4.6 n 58 4 9/14/2021 <5 2.5 n 58
5 9/21/2021 5 5 5 9/21/2021 <5 2.5
6 9/28/2021 4.2 4.2 Mult Factor =1.00 6 9/28/2021 <5 2.5 Mult Factor =1.00
7 10/5/2021 5.5 5.5 Max. Value 5.5 µg/L 7 10/5/2021 <5 2.5 Max. Value 2.5 ug/L
8 10/12/2021 4 4 Max. Pred Cw 5.5 µg/L 8 10/12/2021 <5 2.5 Max. Pred Cw 2.5 ug/L
9 10/13/2021 4 4 9 10/13/2021 <5 2.5
10 10/19/2021 4.2 4.2 10 10/19/2021 <5 2.5
11 10/26/2021 4.2 4.2 11 10/26/2021 <5 2.5
12 11/2/2021 3.8 3.8 12 11/2/2021 <5 2.5
13 11/9/2021 3.6 3.6 13 11/9/2021 <5 2.5
14 11/16/2021 4.2 4.2 14 11/16/2021 <5 2.5
15 11/18/2021 4.1 4.1 15 11/18/2021 <5 2.5
16 11/23/2021 3.7 3.7 16 11/23/2021 <5 2.5
17 11/30/2021 3.4 3.4 17 11/30/2021 <5 2.5
18 12/7/2021 3.2 3.2 18 12/7/2021 <5 2.5
19 12/14/2021 4.4 4.4 19 12/14/2021 <5 2.5
20 12/17/2021 4.3 4.3 20 12/17/2021 <5 2.5
21 12/21/2021 3.7 3.7 21 12/21/2021 <5 2.5
22 12/29/2021 3.7 3.7 22 12/29/2021 <5 2.5
23 1/4/2022 3.5 3.5 23 1/4/2022 <5 2.5
24 1/8/2022 4.9 4.9 24 1/8/2022 <5 2.5
25 1/11/2022 4.4 4.4 25 1/11/2022 <5 2.5
26 1/19/2022 4.3 4.3 26 1/19/2022 <5 2.5
27 1/25/2022 4.5 4.5 27 1/25/2022 <5 2.5
28 2/1/2022 4.7 4.7 28 2/1/2022 <5 2.5
29 2/6/2022 4.5 4.5 29 2/6/2022 <5 2.5
30 2/8/2022 4.4 4.4 30 2/8/2022 <5 2.5
31 2/15/2022 4.5 4.5 31 2/15/2022 <5 2.5
32 2/22/2022 4 4 32 2/22/2022 <5 2.5
33 3/1/2022 3.8 3.8 33 3/1/2022 <5 2.5
34 3/7/2022 4 4 34 3/7/2022 <5 2.5
35 3/9/2022 4.4 4.4 35 3/9/2022 <5 2.5
36 3/15/2022 4.8 4.8 36 3/15/2022 <5 2.5
37 3/22/2022 4.1 4.1 37 3/22/2022 <5 2.5
38 3/29/2022 4.7 4.7 38 3/29/2022 <5 2.5
39 4/5/2022 4.6 4.6 39 4/5/2022 <5 2.5
40 4/12/2022 4.1 4.1 40 4/12/2022 <5 2.5
41 4/19/2022 4.1 4.1 41 4/19/2022 <5 2.5
42 4/26/2022 3.3 3.3 42 4/26/2022 <5 2.5
43 5/3/2022 4.5 4.5 43 5/3/2022 <5 2.5
44 5/10/2022 4.3 4.3 44 5/10/2022 <5 2.5
45 5/11/2022 4.8 4.8 45 5/11/2022 <5 2.5
46 5/17/2022 5 5 46 5/17/2022 <5 2.5
47 5/24/2022 4.5 4.5 47 5/24/2022 <5 2.5
48 6/1/2022 5 5 48 6/1/2022 <5 2.5
49 6/7/2022 4.7 4.7 49 6/7/2022 <5 2.5
50 6/9/2022 4.5 4.5 50 6/9/2022 <5 2.5
51 6/14/2022 4.3 4.3 51 6/14/2022 <5 2.5
52 6/21/2022 4.3 4.3 52 6/21/2022 <5 2.5
53 6/28/2022 5 5 53 6/28/2022 <5 2.5
54 7/6/2022 3.7 3.7 54 7/6/2022 <5 2.5
55 7/12/2022 3.3 3.3 55 7/12/2022 <5 2.5
56 7/19/2022 3.4 3.4 56 7/19/2022 <5 2.5
57 7/22/2022 4.4 4.4 57 7/22/2022 <5 2.5
58 7/26/2022 3.8 3.8 58 7/26/2022 <5 2.5
Use "PASTE SPECIAL-
Values" then "COPY"
. Maximum data
points = 58
Use "PASTE
SPECIAL-Values"
then "COPY" .
Maximum data
points = 58
- 7 -
24970 rpa, data
9/14/2022
REASONABLE POTENTIAL ANALYSIS
Par20 Par21
Silver Zinc
Date Data BDL=1/2DL Results Date Data BDL=1/2DL Results
1 8/24/2021 <1 0.5 Std Dev.0.0000 1 8/24/2021 19 19 Std Dev.3.1848
2 8/31/2021 <1 0.5 Mean 0.5000 2 8/31/2021 23 23 Mean 23.1207
3 9/8/2021 <1 0.5 C.V.0.0000 3 9/8/2021 20 20 C.V.0.1377
4 9/14/2021 <1 0.5 n 58 4 9/14/2021 26 26 n 58
5 9/21/2021 <1 0.5 5 9/21/2021 24 24
6 9/28/2021 <1 0.5 Mult Factor =1.00 6 9/28/2021 21 21 Mult Factor =1.00
7 10/5/2021 <1 0.5 Max. Value 0.500 ug/L 7 10/5/2021 25 25 Max. Value 34.0 ug/L
8 10/12/2021 <1 0.5 Max. Pred Cw 0.500 ug/L 8 10/12/2021 19 19 Max. Pred Cw 34.0 ug/L
9 10/13/2021 <1 0.5 9 10/13/2021 22 22
10 10/19/2021 <1 0.5 10 10/19/2021 24 24
11 10/26/2021 <1 0.5 11 10/26/2021 24 24
12 11/2/2021 <1 0.5 12 11/2/2021 21 21
13 11/9/2021 <1 0.5 13 11/9/2021 22 22
14 11/16/2021 <1 0.5 14 11/16/2021 26 26
15 11/18/2021 <1 0.5 15 11/18/2021 24 24
16 11/23/2021 <1 0.5 16 11/23/2021 25 25
17 11/30/2021 <1 0.5 17 11/30/2021 30 30
18 12/7/2021 <1 0.5 18 12/7/2021 34 34
19 12/14/2021 <1 0.5 19 12/14/2021 27 27
20 12/17/2021 <1 0.5 20 12/17/2021 26 26
21 12/21/2021 <1 0.5 21 12/21/2021 25 25
22 12/29/2021 <1 0.5 22 12/29/2021 22 22
23 1/4/2022 <1 0.5 23 1/4/2022 19 19
24 1/8/2022 <1 0.5 24 1/8/2022 24 24
25 1/11/2022 <1 0.5 25 1/11/2022 20 20
26 1/19/2022 <1 0.5 26 1/19/2022 22 22
27 1/25/2022 <1 0.5 27 1/25/2022 24 24
28 2/1/2022 <1 0.5 28 2/1/2022 25 25
29 2/6/2022 <1 0.5 29 2/6/2022 25 25
30 2/8/2022 <1 0.5 30 2/8/2022 23 23
31 2/15/2022 <1 0.5 31 2/15/2022 25 25
32 2/22/2022 <1 0.5 32 2/22/2022 22 22
33 3/1/2022 <1 0.5 33 3/1/2022 24 24
34 3/7/2022 <1 0.5 34 3/7/2022 20 20
35 3/9/2022 <1 0.5 35 3/9/2022 23 23
36 3/15/2022 <1 0.5 36 3/15/2022 23 23
37 3/22/2022 <1 0.5 37 3/22/2022 21 21
38 3/29/2022 <1 0.5 38 3/29/2022 23 23
39 4/5/2022 <1 0.5 39 4/5/2022 22 22
40 4/12/2022 <1 0.5 40 4/12/2022 20 20
41 4/19/2022 <1 0.5 41 4/19/2022 20 20
42 4/26/2022 <1 0.5 42 4/26/2022 21 21
43 5/3/2022 <1 0.5 43 5/3/2022 22 22
44 5/10/2022 <1 0.5 44 5/10/2022 21 21
45 5/11/2022 <1 0.5 45 5/11/2022 24 24
46 5/17/2022 <1 0.5 46 5/17/2022 20 20
47 5/24/2022 <1 0.5 47 5/24/2022 21 21
48 6/1/2022 <1 0.5 48 6/1/2022 18 18
49 6/7/2022 <1 0.5 49 6/7/2022 20 20
50 6/9/2022 <1 0.5 50 6/9/2022 20 20
51 6/14/2022 <1 0.5 51 6/14/2022 27 27
52 6/21/2022 <1 0.5 52 6/21/2022 21 21
53 6/28/2022 <1 0.5 53 6/28/2022 23 23
54 7/6/2022 <1 0.5 54 7/6/2022 23 23
55 7/12/2022 <1 0.5 55 7/12/2022 22 22
56 7/19/2022 <1 0.5 56 7/19/2022 27 27
57 7/22/2022 <1 0.5 57 7/22/2022 34 34
58 7/26/2022 <1 0.5 58 7/26/2022 23 23
Use "PASTE SPECIAL-
Values" then "COPY"
. Maximum data
points = 58
Use "PASTE SPECIAL-
Values" then "COPY"
. Maximum data
points = 58
- 8 -
24970 rpa, data
9/14/2022
REASONABLE POTENTIAL ANALYSIS
Par22
Dichlorobromomethane
Date Data BDL=1/2DL Results
1 1/17/2018 <5 2.5 Std Dev.2.3073
2 3/14/2018 <5 2.5 Mean 5.6129
3 5/14/2018 6.5 6.5 C.V.0.4111
4 7/9/2018 6.9 6.9 n 31
5 9/12/2018 5.8 5.8
6 11/13/2018 <5 2.5 Mult Factor =1.13
7 1/14/2019 <5 2.5 Max. Value 10.100000 µg/L
8 3/6/2019 <5 2.5 Max. Pred Cw 11.413000 µg/L
9 5/13/2019 <5 2.5
10 7/8/2019 6.8 6.8
11 9/11/2019 9.7 9.7
12 11/12/2019 5.7 5.7
13 12/4/2019 5.4 5.4
14 1/6/2020 3.2 3.2
15 3/2/2020 4 4
16 3/11/2020 6.7 6.7
17 5/4/2020 5.4 5.4
18 7/6/2020 6.4 6.4
19 9/23/2020 4.3 4.3
20 11/2/2020 5.9 5.9
21 1/12/2021 4.3 4.3
22 3/3/2021 6 6
23 5/11/2021 5.6 5.6
24 6/9/2021 8.1 8.1
25 7/7/2021 9.3 9.3
26 9/8/2021 9.1 9.1
27 11/9/2021 7.8 7.8
28 1/11/2022 7.9 7.9
29 3/9/2022 4 4
30 5/3/2022 4.1 4.1
31 7/12/2022 10.1 10.1
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
Use "PASTE SPECIAL-
Values" then "COPY"
. Maximum data
points = 58
- 9 -
24970 rpa, data
9/14/2022
McAlpine Creek WWMF ≥Outfall 001
NC0024970 Freshwater RPA - 95% Probability/95% Confidence Using Metal Translators Qw = 64 MGD
MAXIMUM DATA POINTS = 58
Qw (MGD) = 64.0000 WWTP/WTP Class:IV COMBINED HARDNESS (mg/L)
1Q10S (cfs) = 1.68 IWC% @ 1Q10S = 98.33465504 Acute = 151.39 mg/L
7Q10S (cfs) = 2.00 IWC% @ 7Q10S = 98.02371542 Chronic = 151.16 mg/L
7Q10W (cfs) = 10.00 IWC% @ 7Q10W = 90.84249084
30Q2 (cfs) = 13.50 IWC% @ 30Q2 = 88.02129547
Avg. Stream Flow, QA (cfs) = 62.40 IW%C @ QA = 61.38613861
Receiving Stream:Stream Class:C
PARAMETER RECOMMENDED ACTION
Chronic Applied
Standard Acute n # Det.Max Pred Cw
Acute (FW):345.8
Arsenic C 150 FW(7Q10s)340 ug/L
58 0 2.5 Chronic (FW):153.0
Max MDL = 5
Arsenic C 10 HH/WS(Qavg)ug/L NO DETECTS Chronic (HH):16.3
Max MDL = 5
Acute:66.10
Beryllium NC 6.5 FW(7Q10s)65 ug/L 4 0 2.59
Note: n ≤ 9 C.V. (default)Chronic:6.63
Limited data set NO DETECTS Max MDL = 2
Acute:15.834
Cadmium NC 2.2941 FW(7Q10s)15.5700 ug/L 58 0 0.250
Chronic:2.340
NO DETECTS Max MDL = 0.5
Acute:NO WQS
Total Phenolic Compounds NC 300 A(30Q2)ug/L 31 2 77.7
Chronic:340.8
No value > Allowable Cw
Acute:4,023.1
Chromium III NC 513.9885 FW(7Q10s)3956.1300 µg/L 0 0 N/A
Chronic:524.4
Acute:16.3
Chromium VI NC 11 FW(7Q10s)16 µg/L 0 0 N/A
Chronic:11.2
Chromium, Total NC µg/L 58 0 2.5
NO DETECTS Max MDL = 5
Acute:58.11
Copper NC 36.6743 FW(7Q10s)57.1443 ug/L 58 58 3.90
Chronic:37.41
No value > Allowable Cw
Acute:22.4
Cyanide NC 5 FW(7Q10s)22 10 ug/L 58 0 5.0
Chronic:5.1
NO DETECTS Max MDL = 10PQLUNITSTYPE
Allowable Cw
REASONABLE POTENTIAL RESULTSNC STANDARDS OR EPA CRITERIA
McAlpine Creek HUC 03050103
No RP, Predicted Max < 50% of Allowable Cw - No
Monitoring required
No RP, Predicted Max < 50% of Allowable Cw - No
Monitoring required
No RP, Predicted Max < 50% of Allowable Cw - No
Monitoring required
No RP, Predicted Max < 50% of Allowable Cw - No
Monitoring required
All values non-detect < 10 ug/L - no monitoring
required
Max reported value = 2.5
No RP, Predicted Max < 50% of Allowable Cw - No
Monitoring required
a: No monitoring required if all Total Chromium
samples are < 5 µg/L or Pred. max for Total Cr is <
allowable Cw for Cr VI.
Page 1 of 2
24970 rpa, rpa
9/14/2022
McAlpine Creek WWMF ≥Outfall 001
NC0024970 Freshwater RPA - 95% Probability/95% Confidence Using Metal Translators Qw = 64 MGD
Acute:559.194
Lead NC 21.3941 FW(7Q10s)549.8819 ug/L 58 0 2.500
Chronic:21.825
NO DETECTS Max MDL = 5
Acute:NO WQS
Molybdenum NC 2000 HH(7Q10s)ug/L 58 0 2.5
Chronic:2,040.3
NO DETECTS Max MDL = 5
Acute (FW):1,564.3
Nickel NC 170.6343 FW(7Q10s)1538.2117 µg/L
58 58 5.5 Chronic (FW):174.1
No value > Allowable Cw
Nickel NC 25.0000 WS(7Q10s)µg/L Chronic (WS):25.5
No value > Allowable Cw
Acute:56.9
Selenium NC 5 FW(7Q10s)56 ug/L 58 0 2.5
Chronic:5.1
NO DETECTS Max MDL = 5
Acute:6.675
Silver NC 0.06 FW(7Q10s)6.5641 ug/L 58 0 0.500
Chronic:0.061
NO DETECTS Max MDL = 1
Acute:588.0
Zinc NC 582.1902 FW(7Q10s)578.1905 ug/L 58 58 34.0
Chronic:593.9
No value > Allowable Cw
Acute:NO WQS
Dichlorobromomethane C 17 HH(Qavg)µg/L 31 25 11.41300
Chronic:27.69355
No value > Allowable Cw
No RP, Predicted Max < 50% of Allowable Cw - No
Monitoring required
No RP, Predicted Max < 50% of Allowable Cw - No
Monitoring required
No RP, Predicted Max < 50% of Allowable Cw - No
Monitoring required
No RP, Predicted Max < 50% of Allowable Cw - No
Monitoring required
All values non-detect < 1 ug/L - no monitoring
required
No RP, Predicted Max < 50% of Allowable Cw - No
Monitoring required
No RP, Predicted Max < 50% of Allowable Cw - No
Monitoring required
Page 2 of 2
24970 rpa, rpa
9/14/2022
Date: 9/14/2022
FACILITY: McAlpine Creek WWMF Outfall 001
NPDES PERMIT: NC0024970

Rec. Stream NPDES
1Q10 Flow Limit
[MGD][MGD]
2.0000 1.2903 1.0839 64.0000 10 151.165 151.388 98.0237 98.3347 80.6545455 152.5862
Upstream Hard Avg (mg/L) = 80.65455 ACAH 151.3883
EFF Hard Avg (mg/L) = 152.5862 ACCH 151.1646

Chronic Acute Chronic Acute
[ug/l][ug/l][ug/l][ug/l]
Cadmium (d) 0.58 3.93 0.252 2.29 15.57
Cd -Trout streams 0.58 2.44 0.252 2.29 9.68
Chromium III (d)(h)104 800 0.202 513.99 3956.13
Chromium VI (d)11 16 1.000 11.00 16.00
Chromium, Total (t)N/A N/A
Copper (d)(h)12.7 19.9 0.348 36.67 57.14
Lead (d)(h)3.93 101 0.184 21.39 549.88
Nickel (d)(h)74 665 0.432 170.63 1538.21
Ni - WS streams (t)25 N/A
Silver (d)(h,acute)0.06 6.56 1.000 0.06 6.56
Zinc (d)(h)168 167 0.288 582.19 578.19
Beryllium 6.5 65 1.000 6.5 65
Arsenic (d)150 340 1.000 150 340

(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.
Dissolved to Total Metal Calculator
The Human Health standard for Nickel in Water Supply Streams is 25 mg/L which is Total Recoverable metal standard.
In accordance with Federal Regulations, permit limitations must be written as Total Metals per 40 CFR 122.45(c)
The Human Health standard for Arsenic is 10 µg/L which is Total Recoverable metal standard.
Upstream
Hardness
Average (mg/L)
PARAMETER
Effluent
Hardness
Average
(mg/L)
Dissolved Metals Criteria
after applying hardness
equation
US EPA
Translators- using
Default Partition
Coefficients
(streams)
Total Metal Criteria Total Metal =
Dissolved Metal ÷ Translator
COMMENTS (identify parameters to PERCS Branch to maintain in facility's LTMP/STMP):
Receiving
Stream
summer
7Q10 (CFS)
Receiving
Stream
summer 7Q10
(MGD)
Total Suspended
Solids
-Fixed Value-
(mg/L)
Combined
Hardness
chronic
(mg/L)
Combined
Hardness
Acute
(mg/L)
Instream
Wastewater
Concentration
(Chronic)
Instream
Wastewater
Concentration
(Acute)
Dissolved to Total Metal Calculator
Do NOT enter any data directly into this spreadsheet.
Enter data onto “Table 1” under the Input Sheet and enter
“Effluent Hardness” under the Data Sheet.
In accordance with 40 CFR 122.45 (c ), permits are, have and
must be written as total metals.
This calculator has been inserted into the RPA to calculate
Total Metal allowable allocations once Table 1 has been
completed (Input Sheet) and Effluent hardness has been
entered (Data Sheet).
1)Following the spreadsheet from left to right. First
the allowable allocations for the dissolved metals will
appear for all the metals listed once Table 1 is complete
and effluent hardness entered. Use a default value of 25
mg/L if no hardness data is available. Second,
the Dissolved Metal allocations are divided by the
Translators to determine the Total Metals that can be
allocated to the Permittee. These Total Metals values are
automatically inserted into Table 2 and are the allowable
Total Metal allocations determined for the Permittee prior
to allowing for dilution. See Input sheet Table 2. The final
acute and chronic values shown under the RPA sheet are
the Total Metal values listed in Table 2 divided by the acute
and chronic IWC, respectively.
2)The Translators used in the freshwater RPA are the
Partition Coefficients published by US EPA in 1984. They
are TSS dependent equations and can be found listed with
the WQS hardness dependent equations under the sheet
labeled Equations. A fixed TSS value of 10 mg/L is used to
calculate the Translator values.
3)Pretreatment Facilities –PERCS will need a copy of the
Dissolved to Total Metal Calculator spreadsheet and the
RPA sheet along with the Final Permit.Pretreatment
Facilities are required to renew their Headwords Analysis
after renewal of their permits. Since all their metal
allocations are likely to change PERCS needs to see any new
metal permit limits and the allowable allocations for the
dissolved metals to assess Maximum Allowable Headworks
Loading (MAHL) numbers for each metal based on the
Combined Hardness values used in the permit writers RPA
calculations.
4)For Cadmium, Lead, Nickel, Chromium and Beryllium , if all
the effluent sampling data for the last three to five years
shows the pollutant at concentrations less than the
Practical Quantitative Level (PQL), it is not likely a limit or
monitoring will be put in the permit. However, if the
estimated NPDES permit limit is less than the Practical
Quantitative Limit (particularly, Cadmium and Lead) and
the pollutant is believed to be present, to assess
compliance with the new standards and for future permit
limit development, monitoring for the pollutant will be
required. If the facility is monitoring for the pollutant in its
Pretreatment LTMP, no monitoring is needed in the permit.
5)For monitoring and compliance purposes if Total
Chromium < the Chromium VI chronic Total Metal
NC0024970 McAlpine Creek WWMF 9/14/2022
Month RR (%)Month RR (%)Month RR (%)Month RR (%)
January-18 99.33 July-20 99.30 January-18 99.26 July-20 99.31
February-18 99.28 August-20 99.16 February-18 99.29 August-20 99.10
March-18 99.21 September-20 99.28 March-18 99.19 September-20 99.30
April-18 99.23 October-20 99.28 April-18 99.22 October-20 99.19
May-18 99.28 November-20 99.32 May-18 99.35 November-20 99.28
June-18 99.21 December-20 99.31 June-18 99.27 December-20 99.23
July-18 99.27 January-21 99.30 July-18 99.25 January-21 99.21
August-18 99.19 February-21 99.20 August-18 99.21 February-21 99.14
September-18 99.14 March-21 99.28 September-18 99.17 March-21 99.25
October-18 99.23 April-21 99.33 October-18 99.27 April-21 99.22
November-18 99.16 May-21 99.40 November-18 99.20 May-21 99.28
December-18 99.10 June-21 99.42 December-18 99.20 June-21 99.36
January-19 99.09 July-21 99.35 January-19 99.13 July-21 99.29
February-19 99.21 August-21 99.38 February-19 99.20 August-21 99.33
March-19 99.17 September-21 99.47 March-19 99.23 September-21 99.43
April-19 99.24 October-21 99.54 April-19 99.20 October-21 99.50
May-19 99.29 November-21 99.57 May-19 99.38 November-21 99.45
June-19 99.24 December-21 99.47 June-19 99.30 December-21 99.45
July-19 99.31 January-22 99.37 July-19 99.28 January-22 99.36
August-19 99.23 February-22 99.41 August-19 99.17 February-22 99.37
September-19 99.36 March-22 99.31 September-19 99.30 March-22 99.36
October-19 99.36 April-22 99.31 October-19 99.28 April-22 99.38
November-19 99.20 May-22 99.37 November-19 99.15 May-22 99.38
December-19 99.30 June-22 99.31 December-19 99.36 June-22 99.39
January-20 99.17 July-22 99.28 January-20 99.18 July-22 99.30
February-20 99.15 August-22 February-20 99.23 August-22
March-20 99.17 September-22 March-20 99.15 September-22
April-20 99.20 October-22 April-20 99.26 October-22
May-20 98.91 November-22 May-20 98.76 November-22
June-20 99.17 December-22 June-20 99.07 December-22
Overall CBOD removal rate 99.27 Overall TSS removal rate 99.26
CBOD monthly removal rate TSS monthly removal rate
Reduction in Frequency EvalautionFacility:Permit No.Review period (use 3 yrs)Approval Criteria:Y/N?YYNData Review UnitsWeekly average limitMonthly average limit50% MA3‐yr mean (geo mean for FC)< 50%?200% MA# daily samples >200%<15?200% WA# daily samples >200%< 20?# of non‐monthly limit violations> 2?# civil penalty asessment> 1?Reduce Frequency? (Yes/No)CBOD (summer) mg/L 6 4 2 1.3497436 Y 8 0 Y 0 N 0 N YCBOD (winter) mg/L 12 8 4 1.4146154 Y 16 0 Y 0 N 0 N YTSS mg/L 22.5 15 7.5 1.600627 Y 30 0 Y 0 N 0 N YAmmonia (summer) mg/L 3 1 0.5 0.0535354 Y 2 0 Y 0 N 0 N YAmmonia (winter) mg/L 5.7 1.9 1 0.0549618 Y 3.8 0 Y 0 N 0 N YFecal Coliform #/100 400 200 100 8.2229499 Y 800 0 Y 0 N 0 N Y1. Not currently under SOS2. Not on EPA Quarterly noncompliance report3. Facility or employees convicted of CWA violationsMcAlpine Creek WWMFNC00249708/2019 ‐ 8/2022
NH3/TRC WLA Calculations
Facility: McAlpine Creek WWMF
PermitNo. NC0024970
Prepared By: Nick Coco
Enter Design Flow (MGD):64
Enter s7Q10 (cfs):2
Enter w7Q10 (cfs):10
Total Residual Chlorine (TRC)Ammonia (Summer)
Daily Maximum Limit (ug/l)Monthly Average Limit (mg NH3-N/l)
s7Q10 (CFS)2 s7Q10 (CFS)2
DESIGN FLOW (MGD)64 DESIGN FLOW (MGD)64
DESIGN FLOW (CFS)99.2 DESIGN FLOW (CFS)99.2
STREAM STD (UG/L)17.0 STREAM STD (MG/L)1.0
Upstream Bkgd (ug/l)0 Upstream Bkgd (mg/l)0.22
IWC (%)98.02 IWC (%)98.02
Allowable Conc. (ug/l)17 Allowable Conc. (mg/l)1.0
More stringent than current limit.Consistent with current limit. Maintain limit.
Apply limit.
Ammonia (Winter)
Monthly Average Limit (mg NH3-N/l)
Fecal Coliform w7Q10 (CFS)10
Monthly Average Limit:200/100ml DESIGN FLOW (MGD)64
(If DF >331; Monitor)DESIGN FLOW (CFS)99.2
(If DF<331; Limit)STREAM STD (MG/L)1.8
Dilution Factor (DF)1.02 Upstream Bkgd (mg/l)0.22
IWC (%)90.84
Allowable Conc. (mg/l)2.0
Less stringent than current limit. Maintain limit.
Total Residual Chlorine
1. Cap Daily Max limit at 28 ug/l to protect for acute toxicity
Ammonia (as NH3-N)
1. If Allowable Conc > 35 mg/l, Monitor Only
2. Monthly Avg limit x 3 = Weekly Avg limit (Municipals)
3. Monthly Avg limit x 5 = Daily Max limit (Non-Munis)
If the allowable ammonia concentration is > 35 mg/L, no limit shall be imposed
Fecal Coliform
1. Monthly Avg limit x 2 = 400/100 ml = Weekly Avg limit (Municipals) = Daily Max limit (Non-Muni)

9/13/22 WQS = 12 ng/L V:2013-6
Facility Name
/Permit No. :
Total Mercury 1631E PQL = 0.5 ng/L 7Q10s = 2.000 cfs WQBEL = 12.24 ng/L
Date Modifier Data Entry Value Permitted Flow = 64.000 47 ng/L
1/6/18 <1 0.5
2/4/18 <1 0.5
3/5/18 1 1
4/3/18 <1 0.5
5/9/18 <1 0.5
6/7/18 2.5 2.5
7/13/18 1.2 1.2
8/11/18 3.9 3.9
10/8/18 <1 0.5
11/6/18 <1 0.5
12/5/18 <1 0.5 1.1 ng/L - Annual Average for 2018
1/10/19 <1 0.5
2/8/19 1.3 1.3
3/9/19 <1 0.5
4/7/19 <1 0.5
5/6/19 <1 0.5
6/4/19 9.8 9.8
7/10/19 0.7 0.7
8/8/19 0.8 0.8
9/6/19 0.9 0.9
10/5/19 0.6 0.6
11/17/19 0.7 0.7
12/3/19 0.8 0.8
12/9/19 0.7 0.7 1.4 ng/L - Annual Average for 2019
1/7/20 0.9 0.9
2/5/20 0.6 0.6
3/5/20 0.8 0.8
McAlpine Creek WWMF/NC0024970 No Limit Required
MERCURY WQBEL/TBEL EVALUATION
MMP Required
3/10/20 0.7 0.7
4/3/20 0.9 0.9
5/9/20 0.7 0.7
6/7/20 0.6 0.6
7/13/20 0.6 0.6
8/4/20 <0.5 0.5
9/16/20 0.8 0.8
10/8/20 0.6 0.6
11/6/20 0.8 0.8
12/5/20 0.8 0.8 0.7 ng/L - Annual Average for 2020
1/10/21 1.1 1.1
2/8/21 1 1
3/9/21 0.7 0.7
4/7/21 1 1
5/13/21 <0.5 0.5
6/4/21 0.76 0.76
6/8/21 0.79 0.79
7/10/21 0.66 0.66
8/15/21 1.16 1.16
9/13/21 0.66 0.66
10/12/21 0.69 0.69
11/17/21 0.97 0.97
12/16/21 0.54 0.54 0.8 ng/L - Annual Average for 2021
1/7/22 0.79 0.79
2/5/22 0.93 0.93
3/6/22 0.54 0.54
4/4/22 0.69 0.69
5/10/22 0.65 0.65
6/8/22 <0.5 0.5
7/21/22 <0.5 0.5 0.7 ng/L - Annual Average for 2022
McAlpine Creek WWMF/NC0024970
Mercury Data Statistics (Method 1631E)
2018 2019 2020 2021 2022
# of Samples 11 13 13 13 7
Annual Average, ng/L 1.1 1.4 0.7 0.81 0.657143
Maximum Value, ng/L 3.90 9.80 0.90 1.16 0.93
TBEL, ng/L
WQBEL, ng/L 12.2
47
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A B C D E F G H I J K L M N O P
Wes Bell
Permittee-Facility Name
NPDES Permit Number WWTP expansion
Stream reclass./adjustment
Outfall relocation/adjustment McAlpine Creek 62.4
C 2
6/1/2018 to 12/31/2022 35.35.70 N 80.52.21 W
64.0 Designed Flow,
mgd 64.0
# IUs
# SIUs
# CIUs
# NSCIUs
# IUs w/Local
Permits or Other
Types
#IU Activity
1 Textile
2 Plastic Molding/
Forming
3 Food
4 Chemical
Repackaging
5 Metal Finisher
6 Laundry
7 Metal Finisher
8 Food
9 Textile Chem.
10 OCPSF
11 OCPSF
12 Landfill
13 Metal Finisher
14 Metal Finisher
15 Food
16 Uncontrollable
Flows
17 Solid Waste
Transfer
1) facility has no SIU's, does have Division approved Pretreatment Program that is INACTIVE
2) facility has no SIU's, does not have Division approved Pretreatment Program
3) facility has SIUs and DWQ approved Pretreatment Program
3a) Full Program with LTMP
3b) Modified Program with STMP
4) additional conditions regarding Pretreatment attached or listed below
5) facility's sludge is being land applied or composted
6) facility's sludge is incinerated (add Beryllium and Mercury sampling according to § 503.43)
7) facility's sludge is taken to a landfill, if yes which landfill:
8) other
%
Removal
Rate
PQL from
L/STMP, ug/l
Required PQL
per NPDES
permit
Recomm.
PQL, ug/l
Flow
BOD
TSS
NH3
Arsenic 2.0
Barium
Beryllium(5)
Cadmium(1)0.5
Chromium(1)5.0
Copper(1)2.0
Cyanide
Lead(1)2.0
Mercury(5)0.001
Molybdenum 10.0
Nickel(1)
Selenium 1.0
Silver 1.0
Zinc(1)10.0
Sludge Flow to Disposal
% Solids to Disposal
Oil & Grease
TN
TP
PFAS 1633
1,4 Dioxane
COD
Footnotes:
(1) Always in the LTMP/STMP due to EPA-PT requirement
(2) Only in LTMP/STMP if listed in sludge permit
(3) Only in LTMP/STMP while SIU still discharges to POTW
(4) Only in LTMP/STMP when pollutant is of concern to POTW
(5) In LTMP/STMP, if sewage sludge is incinerated
Please use blue font for the info updated by pw
Please use red font for POC that need to be added/modified in L/STMP sampling plan
Bakkavor Foods USA, Inc.Flow, ammonia, CBOD, COD, max flow rate, oil & grease, phosphorous, TSS, pH 8/1/2021
Brenntag Mid-South, Inc.Flow, ammonia, CBOD, COD, chromium, copper, cyanide, mercury, nickel, lead, phosphorous, TSS, TTO, zinc, pH 11/1/2020
Charlotte Plating, Inc.Flow, ammonia, cadmium, COD, chromium, copper, cyanide, lead, nickel, oil & grease, phosphorous, silver, TSS, TTO, zinc, pH 7/1/2022
WQ0000057
New
NPDES
POC
Previous
NPDES
POC
Required by
EPA PT(1)
POC due to
Sludge (2)
POC due to
SIU (3)
POTW
POC (4)
L/STMP
Effluent Freq.
PQLs review
Comment
POC in L/STMPParameter of Concern
(POC) Check List
NPDES
Effluent Freq.
Sludge Permit No:
4. LTMP/STMP and HWA Review
PW: Find L/STMP document, HWA spreadsheet, DMR, previous and new NPDES permit for next section.
See Comment Box
IWS approval date 10/19/2020
HWA-AT approval date 7/13/2018
eDMR data evaluated from:
NPDES Permit Effective Date
Outfall II
Outfall I
d. IU Summary
17
a. WWTP Capacity Summary
Outfall Long.
Is there a PWS intake downstream of the Facility's Outfall(s)?
Pollutants of Concern (POC) Review Form
c. POC review due to:1/13/2023
QA, cfs:
7Q10 (S), cfs:
Nick Coco
1. Facility's General Information
Date of (draft) Review
NPDES Permit Writer (pw)HWA-AT/LTMP Review
e. Contact Information
Date of (final) Review 10/20/2023 Municipal NPDES renewal Regional Office (RO)
Bill Gintert, [e-mail]
Version: 2022.09.28
RO PT Staff Wes Bell RO NPDES Staff
f. Receiving Stream
7Q10 update
1/1/2024
Chemical Addendum Submittal Date
Facility PT Staff, email
Receiving Stream:
Stream Class
Oufall Lat.
Receiving Stream:
Stream Class
Oufall Lat. NPDES Permit Writer0
17
Industrial User (IU) Name
Comment:Recommend adding 1,4-dioxane monitoring to all metal finishers, laundry and landfill/solid waste transfer; Recommend PFAS for all textiles, plastic molding forming, food, chemical packaging, laundry, OCPSF, uncontrollable flows and landfills/solid waste transfers.
Charlotte Water - McAlpine Creek WWMF
NC0024970
New Industries
Current Permitted Flow, mgd
Mooresville
NPDES Permit Public Notice Date 5/16/2023
Other POC review trigger, explain:
11
6L/STMP approval date:7/6/2018
2. Industrial Users' Information.
QA, cfs:
7Q10, cfs:
Outfall Long.
6.300
b. PT Docs. Summary
Permitted SIU Flow, mgd
YES NO
Facility is approximately 2 miles upstream of the SC/NC border; Treating this border as WS boundary;
Charlotte Water's response to Chemical Addendum: "To the best of our knowledge, all samples collected at McAlpine WWMF that are covered under a method listed in 40 CFR Part 136
and run by a state certified lab, have been reported to NCDWR on our monthly DMR’s. No additional pollutants with methods listed in 40 CFR Part 136 have been analyzed, therefore, the
Chemical Addendum form was not submitted in our application. "
Comments:
IUP Effective Date
1/1/2022Arjobex America, Inc
INOLEX, Inc.
IU Non Conventional Pollutans & Toxic Pollutant
Flow, ammonia, COD, chromium, copper, nickel, oil & grease, TSS, zinc, phosphorous, pH
Flow, ammonia, COD, copper, lead, molybdenum, oil & grease, phosphorous, silver, TSS, TTO, zinc, pH
Flow, ammonia, arsenic, CBOD, COD, cadmium, chromium, copper, cyanide, mercury, molybdenum, nickel, oil & grease, non-polar material,
lead, PCB, phosphorous, selenium, silver, TSS, TTO, zinc, pH
8/12/2021
Aplix, Inc
Waste Connections of North Carolina, Inc.
11/1/2022
Frito Lay Flow, ammonia, CBOD, COD, chromium, copper, nickel, oil & grease, phosphorous, TSS, zinc, pH 5/1/2020
Sludge Disposal Plan:Biosolids residuals are permitted, managed, and disposed under a contract with Synagro. Land application and land filling are the means for ultimate use of the residuals
8/1/2021
Status of Pretreatment Program (check all that apply)
3. Status of Pretreatment Program (check all that apply)
Huntsman International, LLC Flow, ammonia, CBOD, COD, chromium, copper, lead, nickel, oil & grease, phosphorous, TSS, zinc, color, pH 1/3/2023
IGM Resins USA, Inc
12/1/2022
Duff-Norton Flow, ammonia, CBOD, COD, cadmium, chromium, cyanide, copper, nickel, lead, oil & grease, phosphorous, TSS, TTO, zinc, pH, silver 7/1/2018
Union County Public Works Flow, arsenic, ammonia, CBOD, COD, cadmium, chromium, copper, cyanide, lead, mercury, molybdenum, nitrogen, nickel, oil & grease,
phosphorous, selenium, silver, TSS, zinc, pH
2/1/2020
Safe Fleet
Siemens Energy, Inc
Snyder's-Lance, Inc
Flow, ammonia, COD, cadmium, chromium, copper, cyanide, lead, nickel, molybdenum, oil & grease, phosphorous, silver, TSS, TTO, zinc, pH
Flow, ammonia, COD, cadmium, chromium, copper, lead, cyanide, nickel, oil & grease, silver, phosphorous, TTO TSS, zinc, pH
Flow, max flow rate, ammonia, CBOD, COD, chromium, copper, cyanide, lead, nickel, phosphorous, oil & grease, TSS, zinc, pH
11/1/2018
9/1/2021
11/1/2021
Flow, ammonia, CBOD, chromium, COD, copper, cyanide, lead, mercury, nickel, oil & grease, phosphorous, TSS, xylene, zinc, pH 3/1/2019
Mecklenburg County, Foxhole Landfill Flow, silver, ammonia, arsenic, cadmium, COD, CBOD, mercury, phosphorous, selenium, TSS, TTO, zinc, pH 3/1/2020
Flow, max flow rate, ammonia, CBOD, COD, chromium, copper, cyanide, lead, nickel, phosphorous, oil & grease, TSS, zinc, pH
Clintas Corporation Flow, ammonia, CBOD, COD, cadmium, chromium, cyanide, copper, molybdenum, nickel, lead, oil & grease, phosphorous, TSS, TTO, zinc, pH
Page 1 POC Review Form (1)
102
103
104
105
106
107
108
109
110
111
A B C D E F G H I J K L M N O P
Please use orange font and strikethrough for POC that may be removed from L/STMP POC list/sampling plan
Blue shaded cell (D60:H81):Parameters usually included under that POC list
1/1/2024 180 days after effective (date):7/1/2024 Permit writer, please add list of required/recommended PT updates in NPDES permit cover letter.
6. Pretreatment updates in response to NPDES permit renewal
NPDES Permit Effective Date
5. Comments
Facility Summary/background information/NPDES-PT regulatory action: POC to be added/modified in L/STMP:
ORC's comments on IU/POC:
POC submitted through Chemical
Addendum or Supplemental Chemical
Datasheet:
Additional pollutants added to L/STMP due
to POTWs concerns:
NPDES pw's comments on IU/POC:
Page 2 POC Review Form (1)
1
Coco, Nick A
From:Sypolt, Shannon <[e-mail]>
Sent:Monday, February 13, 2023 4:08 PM
To:Coco, Nick A
Cc:Montebello, Michael J; Macomber, Maggie; Lockler, Joseph
Subject:RE: [EXT]RE: [External] RE: Additional Information Request: Irwin & Sugar Creek NPDES Permit
Renewal Applications
Follow Up Flag:Follow up
Flag Status:Flagged
CAUTION: External email. Do not click links or open attachments unless you verify. Send all suspicious email as an attachment to 
Report Spam. 

Hi Nick, 

Per you request below and pertaining to confirmation that our application remains accurate, to the best of our 
knowledge, no additional parameters have been sampled for since our original application was submitted.  Therefore no 
additional parameters have been identified in the effluent and no chemical addendum sheets are necessary.  Thank you. 

Shannon Sypolt
Water Quality Program Administrator
Environmental Management
 4222 Westmont Drive / Charlotte, NC 28217
P: 704-336-4581 / C: 704-634-6984 / charlottewater.org

From: Coco, Nick A <[e-mail]>  
Sent: Monday, February 6, 2023 3:59 PM 
To: Sypolt, Shannon <[e-mail]> 
Cc: Montebello, Michael J <[e-mail]>; Macomber, Maggie 
<[e-mail]>; Lockler, Joseph <[e-mail]> 
Subject: [EXT]RE: [External] RE: Additional Information Request: Irwin & Sugar Creek NPDES Permit Renewal Applications 

Hi Shannon, 

Thank you for getting this to us and thank you for the call last week to discuss the status of these permits.  

To justify that the application remains accurate with regard to which parameters have been sampled for at each of these 
facilities, please verify that no additional parameters have been sampled for, before or after the application was 
submitted, and therefore no additional parameters have been identified in the effluents of each plant and no chemical 
addendum sheets are necessary.  

Thanks again, 
2
Nick Coco, PE (he/him/his) 
Engineer III  
NPDES Municipal Permitting Unit 
NC DEQ / Division of Water Resources / Water Quality Permitting 
Office: (919) 707‐3609 
[e-mail]  
**Email is preferred but I am available to talk by via Microsoft Teams** 

Physical Address: 512 North Salisbury St.,Raleigh, NC, 27604 
Mailing Address: 1617 Mail Service Center, Raleigh, NC, 27699‐1617 

From: Sypolt, Shannon <[e-mail]>  
Sent: Friday, February 3, 2023 4:57 PM 
To: Coco, Nick A <[e-mail]> 
Cc: Montebello, Michael J <[e-mail]>; Macomber, Maggie 
<[e-mail]>; Lockler, Joseph <[e-mail]> 
Subject: [External] RE: Additional Information Request: Irwin & Sugar Creek NPDES Permit Renewal Applications 

CAUTION: External email. Do not click links or open attachments unless you verify. Send all suspicious email as an attachment to 
Report Spam. 

Hi Nick, 

Per your request below please see the following additional information: 

1) Please see the attached monitoring frequency reduction request summary for Irwin and Sugar Creek 
2) I have confirmed with our Pretreatment Program Supervisor that no SIU’s in our Pretreatment Program have 
been sampled for 1,4 Dioxane.  Additionally, we have not collected any 1,4 Dioxane samples from Irwin, 
Sugar, or McAlpine. 
3) Regarding the chemical addendum submission, Charlotte Water believes we have met the requirement 
needed to properly submit this information as outlined on NCDWR’s website and we have previously 
certified our application as being true, accurate, and complete.  Please see the information below that we 
are referring to: 

3

4

If you have any questions concerning the information contained in this email, or if you need any further information, just 
let me know.  Thank you for the opportunity to provide this additional information.  Happy Friday!!! 

Respectfully, 

Shannon Sypolt
Water Quality Program Administrator
Environmental Management

4222 Westmont Drive / Charlotte, NC 28217
P: 704-336-4581 / C: 704-634-6984 / charlottewater.org

From: Coco, Nick A <[e-mail]>  
Sent: Friday, January 13, 2023 1:50 PM 
To: Sypolt, Shannon <[e-mail]> 
Cc: Montebello, Michael J <[e-mail]> 
Subject: [EXT]RE: [External] RE: [EXT]Additional Information Request: NC0024970 McAlpine Creek NPDES Permit 
Application 

Hi Shannon, 

I hope all is well. 

I’m making good progress on the 3 renewals for McAlpine Creek WWMF, Irwin Creek WWTP and Sugar Creek WWTP. I 
was hoping you could just provide me with the monitoring frequency reduction request and criteria check for the Irwin 
and Sugar Creek plants. I also wanted to clarify the chemical addendum. We will need the addendum for each of these 
facilities. I know that you had mentioned that the addendum was not necessary since no additional monitoring had been 
conducted, but we will need that written on the chemical addendum form and signed (anywhere on the form will do). If 
no additional sampling was conducted, you can just note that no additional sampling was conducted and therefore no 
additional parameters were identified. 

5
One last question I have is related to 1,4‐dioxane. Has Charlotte Water conducted any monitoring of 1,4‐dioxane at 
these 3 plants? It appears that each facility has at least one industry type linked to use of 1,4‐dioxane in their 
pretreatment programs.  

Thanks in advance for your time and help on this, 
Nick Coco, PE (he/him/his) 
Engineer III  
NPDES Municipal Permitting Unit 
NC DEQ / Division of Water Resources / Water Quality Permitting 
Office: (919) 707‐3609 
[e-mail]  
**Email is preferred but I am available to talk by via Microsoft Teams** 

Physical Address: 512 North Salisbury St.,Raleigh, NC, 27604 
Mailing Address: 1617 Mail Service Center, Raleigh, NC, 27699‐1617 

From: Sypolt, Shannon <[e-mail]>  
Sent: Tuesday, October 4, 2022 10:00 AM 
To: Coco, Nick A <[e-mail]> 
Cc: Macomber, Maggie <[e-mail]>; Lockler, Joseph <[e-mail]>; 
Montebello, Michael J <[e-mail]>; Jarrell, Jackie <[e-mail]>; Smith, Reid 
<[e-mail]> 
Subject: [External] RE: [EXT]Additional Information Request: NC0024970 McAlpine Creek NPDES Permit Application 

CAUTION: External email. Do not click links or open attachments unless you verify. Send all suspicious email as an attachment to 
Report Spam. 

Good morning Nick, 

Please see the following responses, and their associated attached documents, for the information that you have 
requested in your email below: 

1. Please see the five attached PPA’s that were completed since McAlpine’s last permit renewal.  Although 
McAlpine’s permit only required three PPA’s be performed during the last permit cycle, CLTWater conducts 
PPA’s annually at all of our facilities. 
2. Our biosolids permit number is WQ0000057. 
3. The estimated average daily volume of I&I is 4.176 MGD. 
4. McAlpine WWMF would like to continue reduced monitoring frequencies (2x/week) for conventional 
parameters.  Please see the attached spreadsheet that demonstrates McAlpine WWMF has met all the 
requirements for reduced monitoring frequencies as an “Exceptionally Performing Facility”.   
6
5. To the best of our knowledge, all samples collected at McAlpine WWMF that are covered under a method listed 
in 40 CFR Part 136 and run by a state certified lab, have been reported to NCDWR on our monthly DMR’s.  No 
additional pollutants with methods listed in 40 CFR Part 136 have been analyzed, therefore, the Chemical 
Addendum form was not submitted in our application.   
6. Per your request, please see the attached CLTWater Mercury Minimization Plan.   
7. The treatment unit components list submitted in our permit application is accurate and represents all 
permanent treatment units currently present at McAlpine. 

If you have any questions concerning the information contained in this email, or if you need any additional information, 
please feel free to contact me directly.  Thank you for your assistance with the renewal of McAlpine’s NPDES permit. 

Respectfully, 

Shannon Sypolt
Water Quality Program Administrator
Environmental Management
 4222 Westmont Drive / Charlotte, NC 28217
P: 704-336-4581 / C: 704-634-6984 / charlottewater.org

From: Coco, Nick A <[e-mail]>  
Sent: Tuesday, September 13, 2022 11:47 AM 
To: [e-mail] 
Cc: Jarrell, Jackie <[e-mail]>; Montebello, Michael J <[e-mail]> 
Subject: [EXT]Additional Information Request: NC0024970 McAlpine Creek NPDES Permit Application 

Hi Kim, 
I hope all is well on your end. 

I have begun reviewing the NPDES renewal application for NC0024970 McAlpine Creek WWTP and have the following 
comments: 

1. Please provide the 3 effluent pollutant scans taken during this permit period. 
2. Please provide the permit number associated with Charlotte Water’s sludge disposal agreement with Synagro. 
3. Please provide the estimated average daily volume of I&I. It appears this wasn’t noted on the attachment or in 
the application. 
4. Charlotte Water was granted 2/week monitoring for BOD, ammonia, TSS and fecal coliform based on 2012 DWR 
Guidance Regarding the Reduction of Monitoring Frequencies in NPDES Permits for Exceptionally Performing 
Facilities. The renewal application does not include a request for continuation of this monitoring frequency 
reduction. If this is a mistake, and Charlotte Water would like to continue 2/week monitoring for these 
parameters, please submit a request to continue this requirement and include confirmation of the approval 
criteria outlined in the attached guidance document. 
5. As required by Session Law 2018‐5, Senate Bill 99, Section 13.1(r), every applicant shall now submit 
documentation of any additional pollutants for which there are certified methods with the permit application if 
their discharge is anticipated. The list of pollutants may be found in 40 CFR Part 136, which is incorporated by 
reference. If there are additional pollutants with certified methods to be reported, please submit the Chemical 
Addendum to NPDES Application table with your application and, if applicable, list the selected certified 
analytical method used. If there are no additional pollutants to report, this form is not required to be included 
with your application.  This requirement applies to all NPDES facilities. The Chemical Addendum to NPDES 
7
Application will be required for any type of facility with an NPDES permit, depending on whether those types of 
pollutants are found in your wastewater. Please fill out, sign and submit the Chemical Addendum to NPDES 
Application. 
6. Please provide a copy of the Mercury Minimization Plan prepared for this facility, per Special Condition A.(10) of 
the current permit. 
7. Please verify the accuracy of this component list for the McAlpine Creek WWTP: 

Thank you in advance for all of your help with this. If you have any questions for me along the way, please do not 
hesitate to reach out. 

Best, 
Nick Coco, PE (he/him/his) 
Engineer III  
NPDES Municipal Permitting Unit 
NC DEQ / Division of Water Resources / Water Quality Permitting 
Office: (919) 707‐3609 
[e-mail]  
**Email is preferred but I am available to talk by via Microsoft Teams** 

Physical Address: 512 North Salisbury St.,Raleigh, NC, 27604 
Mailing Address: 1617 Mail Service Center, Raleigh, NC, 27699‐1617 

Whole Effluent Toxicity Testing and Self Monitoring Summary CMUD‐McAlpine WWTPNC0024970/001chr lim: 90%Ceri7dPFBegin:10/1/2017Freq:QMar Jun Sep DecNonComp:SingleCounty:MecklenburgRegion:MROBasin:CTB347Q10:0.3IWC:99.35SOC_JOC:PF:64.0JFMAMJJASOND2018‐‐Pass(s) >100(P)‐‐Pass(s)‐‐Pass‐‐Pass(s)2019‐‐Pass(s)‐‐>100(P) Pass(s)‐‐Pass(s)‐‐Pass(s)2020‐‐Pass(s)‐‐Pass(s)‐‐>100(P) Pass‐‐Pass2021‐‐Pass‐‐Pass (S)‐‐Pass (S) Pass (S)‐‐Pass >100 (P)2022‐‐Pass (S) Pass (S) >100 (P)‐‐Pass (S) Pass (S)‐‐‐‐‐‐CMUD‐McDowell Cr. WWTPNC0036277/001chr lim.:  90%Ceri7dPFBegin:1/1/2014Freq:QJan Apr Jul OctNonComp:SingleCounty:MecklenburgRegion:MROBasin:CTB337Q10:1.80IWC:85SOC_JOC:PF:12.0JFMAMJJASOND2018 Pass(s) 92.5(P)‐‐Pass(s)‐‐Pass(s)‐‐Pass(s)‐‐2019 Pass(s)‐‐Pass(s) >100(P)‐‐Pass(s)‐‐Pass(s)‐‐2020 Pass(s)‐‐Pass(s)‐‐97.5 Pass Pass‐‐Pass‐‐2021 Pass‐‐Pass (S) Pass (S)‐‐Pass (S) Pass (S)‐‐>100 (P) Pass (S) Pass (S)‐‐2022 Pass (S) Pass (S) >100 (P)‐‐Pass (S) Pass (S)‐‐‐‐‐‐‐‐Coats American‐Sevier PlantNC0004243/001chr lim: 15%Ceri7dPFBegin:12/1/2017Freq:QFeb May Aug NovNonComp:SingleCounty:McDowellRegion:AROBasin:CTB307Q10:18.0IWC:14.7SOC_JOC:PF:2.0JFMAMJJASOND2018‐Pass‐‐Pass‐‐Pass‐‐Pass‐2019‐Pass‐‐Pass‐‐Pass‐‐Pass‐2020‐Pass‐‐Pass‐‐Pass‐‐Pass‐2021‐Pass‐‐Pass‐‐Pass‐‐Pass‐2022‐Fail5.3 (NC)21.210.6 (NC)>60>60‐‐‐‐‐Coddle Creek WTPNC0083119/00190% chr montCeri7dPFBegin:12/1/2013Freq:QJan Apr Jul OctNonComp:County:CabarrusRegion:MROBasin:YAD117Q10:IWC:SOC_JOC:PF:0.30JFMAMJJASOND2018 Pass‐‐Pass‐‐Fail‐‐Pass‐‐2019 Pass‐‐Pass‐‐Pass‐‐Pass‐‐2020 Pass‐‐Pass‐‐FailPass‐Pass‐‐2021 Pass‐‐Pass‐‐Pass‐‐Pass‐‐2022 Pass‐‐Pass‐‐Pass‐‐‐‐‐Cofield Facility (RO & Cooling Water)NC0089516/001Chr Limit:  90%Ceri7dPFBegin:9/1/2020Freq:QJan Apr Jul OctNonComp:County:HertfordRegion:WAROBasin:CHO017Q10:IWC:SOC_JOC:PF:JFMAMJJASOND2018 Fail‐‐Fail‐FailFail‐‐Pass‐‐2019 Pass‐‐Pass‐‐Pass‐‐FailH‐2020 Pass‐‐Pass‐‐Pass‐‐Pass‐‐2021 Pass‐‐Pass‐‐Pass‐‐FailFail 94.9 >1002022 Pass‐‐Pass‐‐Pass‐‐‐‐‐Page 24 of 117Legend:  P= Fathead minnow (Pimphales promelas), H=No Flow (facility is active), s = Split test between Certified Labs

North Carolina Department of Environmental Quality  Division of Water Resources
512 North Salisbury Street  1617 Mail Service Center  Raleigh, North Carolina 27699-1617
919.707.9000
September 28, 2021
M E M O R A N D U M
TO: Permit Files:
NC0024937, Sugar Creek WWTP
NC0024945, Irwin Creek WWTP
NC0024970, McAlpine Creek WWTP
NC0036277, McDowell Creek WWTP
NC0089630, Joe C. Stowe, Jr., RWRRF
FROM: Mike Templeton
SUBJECT: Charlotte Water Permits – Proposed Uniform Nutrient Conditions

Charlotte Water owns and operates five wastewater facilities that are subject to nutrient limits.
Charlotte has pointed out that the nutrient conditions in four of the five permits contain minor but not
insignificant differences in terminology and content. These permits should be modified at the first
opportunity to improve clarity and uniformity. This memo provides a brief overview of the nutrient
conditions. This memo and a markup copy of each facility’s permit has been added to its LaserFiche
folder for 2021, and the Word file for each permit has been saved to its “NPDES Permits” folder on
the S: drive.
The five facilities are currently subject to the following nutrient requirements:
• The Sugar, Irwin, and McAlpine Creek facilities are subject to a single, collective Total
Phosphorus (TP) limit. The TP limit is the result of an agreement with SC DHEC that
implements a downstream phosphorus TMDL. The “bubble” limit is included in the McAlpine
Creek permit for internal outfall TP01, and the other permits include a cross-reference to that
permit and limit. One source of confusion is the inconsistent use of terms within each permit and
among the three.
• The McAlpine Creek facility is the largest of Charlotte’s plants (64 MGD). Its permit also
includes an individual TP limit, based on the same settlement agreement, to ensure a certain level
of performance. Another source of confusion is the inconsistent use of terms and methods
between the collective and individual requirements in the permit.
• The McDowell Creek permit includes seasonal Monthly Average mass limits for Total Nitrogen
(TN) and Total Phosphorus. The limits were based on modeling of Mountain Island Lake and
McDowell Creek Cove to protect for the chlorophyll-a water quality standard. The nutrient
requirements are clear enough within the permit, but terms and methods differ from the other
permits.
• The Joe Stowe permit includes total seasonal limits for TN and TP in accordance with the Lake
Wylie Nutrient TMDL. The new facility has not yet been built, and the Cities of Belmont and
Mount Holly will connect to Charlotte’s collection system and decommission their own treatment
plants. The timing of those connections is uncertain and will affect the amount of nutrient
Charlotte Water Permits – Proposed Uniform Nutrient Conditions
September 28, 2021
Page 2

Memo to file - proposed changes to Charlotte Water permits 20210928
4/27/2023 1:45 PM
allocations available to Charlotte for the Stowe discharge. Thus, the permit includes limits for
several connection sequences. We are not proposing changes to the Stowe permit at this time.
The various nutrient limits and permit conditions were established at different times to implement
different control strategies. As a result, the terminology, reporting requirements, and mass calculation
methods vary among the permits and, in some cases, within a given permit.
Charlotte Water has asked the Division to revise the Sugar, Irwin, and McAlpine Creek permits to
improve the uniformity of their nutrient conditions. We propose to modify the McDowell Creek
permit, as well, so that the conditions are more consistent across all of the permits. The changes will
not affect the TN and TP limits or monitoring requirements for the facilities.
The Joe Stowe permit does not require changes at this time; instead, it is being used, as much as
possible, as the template for conditions in the other permits.

(NOTE: It may be possible to perform minor mods for some facilities rather than wait for their
upcoming renewals. In that case, when the first of the permits is renewed, the mods for the others
could be issued at the same time. So permit writers should note that the nutrient updates described
here for a particular facility may have already been made by the time its permit comes up for
renewal.)

Let me know if you have any questions regarding these modifications.
Attachments: Summary of Proposed Changes
Permits, including proposed nutrient revisions
NC0024937, Sugar Creek WWTP
NC0024945, Irwin Creek WWTP
NC0024970, McAlpine Creek WWTP
NC0036277, McDowell Creek WWTP
NC0089630, Joe C. Stowe, Jr., RWRRF
eCopy (w/o attachments): Mike Montebello, Municipal Permitting

Charlotte Water Permits – Proposed Uniform Nutrient Conditions
September 28, 2021
Page 3

Memo to file - proposed changes to Charlotte Water permits 20210928
4/27/2023 1:45 PM

Summary of Proposed Changes – for Discussion with Charlotte Water

All four permits: McAlpine, Sugar, Irwin, and McDowell Creek
• Applied more consistent terminology, units of measure, and parameter codes for the
various measures of TP.
• Applied consistent methods for calculation of TN and TP loads (see figure on next page).
• Required reporting of interim calculation results, to make it easier to see how the final
results were derived.

The “bubble” permits: McAlpine, Sugar, and Irwin Creek
• Updated the “Combined Limitations” condition and edited to include the revised
terminology, etc. The same language is used in all three permits.
• Applied a uniform method for TN and TP calculations, as shown in this figure. Each plant
would report its own results up through the 12-Month TP Loads, and McAlpine would
continue to report the Combined TP Load for the three.

McAlpine Creek
• A.(1.): Added Total Monthly Flow (TMF) reporting, created separate rows for TP
concentration and mass, applied new parameter names in the table and footnotes to
improve clarity, provided clearer linkage between the limits page, footnotes, and the other
TP special conditions.
• A.(7.): Applied the new parameter names and added linkage to the limits page and
calculations condition.
• A.(8.): Applied the new terminology and described the calculations for each measure of TP
used on the limits page. Clarified how the combined TP loads would be calculated and
where they would be reported.

Sugar Creek, Irwin Creek
• Similar to McAlpine Creek except that the limits pages do not include the bubble limit, and
the TP special conditions do not repeat the requirements for calculation and reporting of the
combined 12-month TP load.

McDowell Creek
• A.(1.): Separated concentration and mass requirements for clarity, applied new TP terms.
Linked the limits page to the mass calculations condition.
• Added a version of the calculations condition tailored to this permits requirements.

Charlotte Water Permits – Proposed Uniform Nutrient Conditions
September 28, 2021
Page 4

Memo to file - proposed changes to Charlotte Water permits 20210928
4/27/2023 1:45 PM

Calculation of Combined Nutrient Loads

Monthly Flow (MG)
X Monthly TP Load (lb/mo) 12-Month TP Load (lb/yr)
Average TP (mg/L)

Sugar, NC0024937
Monthly Flow (MG)
X Monthly TP Load (lb/mo) 12-Month TP Load (lb/yr)
Average TP (mg/L)

Combined TP Load (lb/day)
@ Outfall TP01, McAlpine NC0024970
Irwin, NC0024945
Monthly Flow (MG)
X Monthly TP Load (lb/mo) 12-Month TP Load (lb/yr)
Average TP (mg/L)

McAlpine, NC0024970

÷ Days Daily TP Load (lb/day)
@ Outfall 001, McAlpine NC0024970
McAlpine, NC0024970




+
+
MRs Between and Violation Category:Program Category:
Param Name County:Subbasin:%Violation Action:
Major Minor:%
Permit:
Facility Name:
Region:--NC0024970
%%
%
%
Limit Violation %
%
9 2017 9 2022
MONITORING REPORT(MR) VIOLATIONS for:09/13/22Report Date:1Page:of 1
PERMIT:FACILITY:COUNTY:REGION:
%
Over
UNIT OF
MEASURE VIOLATION ACTIONVIOLATION TYPECALCULATED
VALUELIMITFREQUENCYVIOLATION
DATEPARAMETERLOCATIONMONITORING
REPORT
-
EPA
United States Environmental Protection Agency
Washington, D.C. 20460
Water Compliance Inspection Report
Form Approved.
OMB No. 2040-0057
Approval expires 8-31-98
Section A: National Data System Coding (i.e., PCS)
Transaction Code NPDES yr/mo/day Inspection Type Inspector Fac Type
1 N 52 NC0024970 22/02/25 C S31112171819 20
21 66
Inspection Work Days Facility Self-Monitoring Evaluation Rating B1 QA ----------------------Reserved-------------------
2.0 4 N N67707172 73 74 75 80
Section B: Facility Data
Name and Location of Facility Inspected (For Industrial Users discharging to POTW, also include
POTW name and NPDES permit Number)
McAlpine Creek WWTP
12701 Lancaster Hwy
Pineville NC 28134
Entry Time/Date Permit Effective Date
Exit Time/Date Permit Expiration Date
09:15AM 22/02/25 17/10/01
Name(s) of Onsite Representative(s)/Titles(s)/Phone and Fax Number(s)
///
Keith Allen Purgason/ORC/704-542-0736/
Other Facility Data
01:35PM 22/02/25 21/06/30
Name, Address of Responsible Official/Title/Phone and Fax Number
Angela D Charles,5100 Brookshire Blvd Charlotte NC
282163371/Director/704-336-5911/
Contacted
No
Section C: Areas Evaluated During Inspection (Check only those areas evaluated)
Permit Flow Measurement Operations & Maintenance Records/Reports
Self-Monitoring Program Sludge Handling Disposal Facility Site Review Effluent/Receiving Waters
Laboratory
Section D: Summary of Finding/Comments (Attach additional sheets of narrative and checklists as necessary)
(See attachment summary)
Name(s) and Signature(s) of Inspector(s)Agency/Office/Phone and Fax Numbers Date
Wes Bell DWR/MRO WQ/704-663-1699 Ext.2192/
Signature of Management Q A Reviewer Agency/Office/Phone and Fax Numbers Date
Andrew Pitner DWR/MRO WQ/704-663-1699 Ext.2180/
EPA Form 3560-3 (Rev 9-94) Previous editions are obsolete.
Page#1
NPDES yr/mo/day
22/02/25
Inspection Type
C3111218
1
Section D: Summary of Finding/Comments (Attach additional sheets of narrative and checklists as necessary)
On-site Representatives:
The following Charlotte Water personnel were in attendance during the inspection : Mr. Keith
Purgason, Mr. Reid Smith, Mr. Joseph Lockler and Mr. Shannon Sypolt.
NC0024970 17
Page#2
Permit:NC0024970
Inspection Date:02/25/2022
Owner - Facility:
Inspection Type:
McAlpine Creek WWTP
Compliance Evaluation
Permit Yes No NA NE
(If the present permit expires in 6 months or less). Has the permittee submitted a new
application?
Is the facility as described in the permit?
# Are there any special conditions for the permit?
Is access to the plant site restricted to the general public?
Is the inspector granted access to all areas for inspection?
Charlotte Water implements a Division approved Industrial Pretreatment Program. The
Division received Charlotte Water’s renewal package on 1/4/20.
Construction activities associated with the approved Reliability and Process
Improvements projects are ongoing.
The last compliance inspection (bio-monitoring) at this facility was performed by DWR
staff on 9/22/20.
Comment:
Record Keeping Yes No NA NE
Are records kept and maintained as required by the permit?
Is all required information readily available, complete and current?
Are all records maintained for 3 years (lab. reg. required 5 years)?
Are analytical results consistent with data reported on DMRs?
Is the chain-of-custody complete?
Dates, times and location of sampling
Name of individual performing the sampling
Results of analysis and calibration
Dates of analysis
Name of person performing analyses
Transported COCs
Are DMRs complete: do they include all permit parameters?
Has the facility submitted its annual compliance report to users and DWQ?
(If the facility is = or > 5 MGD permitted flow) Do they operate 24/7 with a certified
operator on each shift?
Is the ORC visitation log available and current?
Is the ORC certified at grade equal to or higher than the facility classification?
Is the backup operator certified at one grade less or greater than the facility
classification?
Is a copy of the current NPDES permit available on site?
Facility has copy of previous year's Annual Report on file for review?
Page#3
Permit:NC0024970
Inspection Date:02/25/2022
Owner - Facility:
Inspection Type:
McAlpine Creek WWTP
Compliance Evaluation
Record Keeping Yes No NA NE
The records reviewed during the inspection were organized and well maintained.
Discharge monitoring reports (eDMRs) were reviewed for the period January 2021
through December 2021. No limit and/or monitoring violations were reported.
Comment:
Laboratory Yes No NA NE
Are field parameters performed by certified personnel or laboratory?
Are all other parameters(excluding field parameters) performed by a certified lab?
# Is the facility using a contract lab?
# Is proper temperature set for sample storage (kept at less than or equal to 6.0
degrees Celsius)?
Incubator (Fecal Coliform) set to 44.5 degrees Celsius+/- 0.2 degrees?
Incubator (BOD) set to 20.0 degrees Celsius +/- 1.0 degrees?
Influent and effluent analyses (including field) are performed under Charlotte Water’s
Environmental Services Laboratory Certification #192. ETT and ETS (chronic toxicity)
have also been contracted to provide analytical support.
Comment:
Influent Sampling Yes No NA NE
# Is composite sampling flow proportional?
Is sample collected above side streams?
Is proper volume collected?
Is the tubing clean?
# Is proper temperature set for sample storage (kept at less than or equal to 6.0
degrees Celsius)?
Is sampling performed according to the permit?
The subject permit requires influent BOD and TSS composite samples. Facility staff
check the sampler aliquot volumes on a daily basis.
Comment:
Effluent Sampling Yes No NA NE
Is composite sampling flow proportional?
Is sample collected below all treatment units?
Is proper volume collected?
Is the tubing clean?
# Is proper temperature set for sample storage (kept at less than or equal to 6.0
degrees Celsius)?
Is the facility sampling performed as required by the permit (frequency, sampling type
representative)?
Page#4
Permit:NC0024970
Inspection Date:02/25/2022
Owner - Facility:
Inspection Type:
McAlpine Creek WWTP
Compliance Evaluation
Effluent Sampling Yes No NA NE
The subject permit requires composite and grab effluent samples. Facility staff check
the sampler aliquot volumes on a daily basis.
Comment:
Upstream / Downstream Sampling Yes No NA NE
Is the facility sampling performed as required by the permit (frequency, sampling type,
and sampling location)?
Comment:
Operations & Maintenance Yes No NA NE
Is the plant generally clean with acceptable housekeeping?
Does the facility analyze process control parameters, for ex: MLSS, MCRT, Settleable
Solids, pH, DO, Sludge Judge, and other that are applicable?
The wastewater treatment facility appeared to be properly operated and well
maintained. Facility staff incorporate a comprehensive process control program with all
measurements being properly documented and maintained on-site. In-depth
operation and maintenance records are also maintained on-site. Approximately
Fourteen (14) SCADA stations are located throughout the treatment plant site.
Odor control systems are connected to the influent pump station, primary clarifiers,
sludge thickening/dewatering and bio-solids storage facility.
Comment:
Bar Screens Yes No NA NE
Type of bar screen
a.Manual
b.Mechanical
Are the bars adequately screening debris?
Is the screen free of excessive debris?
Is disposal of screening in compliance?
Is the unit in good condition?
Comment:
Grit Removal Yes No NA NE
Type of grit removal
a.Manual
b.Mechanical
Is the grit free of excessive organic matter?
Is the grit free of excessive odor?
# Is disposal of grit in compliance?
Page#5
Permit:NC0024970
Inspection Date:02/25/2022
Owner - Facility:
Inspection Type:
McAlpine Creek WWTP
Compliance Evaluation
Grit Removal Yes No NA NE
Screenings and grit are disposed at a permitted landfill.Comment:
Pump Station - Influent Yes No NA NE
Is the pump wet well free of bypass lines or structures?
Is the wet well free of excessive grease?
Are all pumps present?
Are all pumps operable?
Are float controls operable?
Is SCADA telemetry available and operational?
Is audible and visual alarm available and operational?
Comment:
Equalization Basins Yes No NA NE
Is the basin aerated?
Is the basin free of bypass lines or structures to the natural environment?
Is the basin free of excessive grease?
Are all pumps present?
Are all pumps operable?
Are float controls operable?
Are audible and visual alarms operable?
# Is basin size/volume adequate?
The facility is equipped with an eighty-five (85) million gallon equalization basin.Comment:
Primary Clarifier Yes No NA NE
Is the clarifier free of black and odorous wastewater?
Is the site free of excessive buildup of solids in center well of circular clarifier?
Are weirs level?
Is the site free of weir blockage?
Is the site free of evidence of short-circuiting?
Is scum removal adequate?
Is the site free of excessive floating sludge?
Is the drive unit operational?
Is the sludge blanket level acceptable?
Page#6
Permit:NC0024970
Inspection Date:02/25/2022
Owner - Facility:
Inspection Type:
McAlpine Creek WWTP
Compliance Evaluation
Primary Clarifier Yes No NA NE
Is the sludge blanket level acceptable? (Approximately ¼ of the sidewall depth)
All eight (8) primary clarifiers (4 – North Train and 4 – South Train) were in service.Comment:
Nutrient Removal Yes No NA NE
# Is total nitrogen removal required?
# Is total phosphorous removal required?
Type Biological
# Is chemical feed required to sustain process?
Is nutrient removal process operating properly?
The facility continues to operate two converted aeration basins (North Train) as
fermenters to enhance nutrient reductions.
Ferric chloride can also be added into the final clarifier effluent to reduce nutrient
levels.
Comment:
Aeration Basins Yes No NA NE
Mode of operation Ext. Air
Type of aeration system Diffused
Is the basin free of dead spots?
Are surface aerators and mixers operational?
Are the diffusers operational?
Is the foam the proper color for the treatment process?
Does the foam cover less than 25% of the basin’s surface?
Is the DO level acceptable?
Is the DO level acceptable?(1.0 to 3.0 mg/l)
The facility is equipped with twenty-six (26) aeration basins (10 – North Train and 16 –
South Train). All aeration basins were in service except two aeration basins being
rehabbed in the South Train. Magnesium hydroxide is added to maintain appropriate
alkalinity/pH levels.
The foam was greater than 25% of the basin’s surface; however, no foam carryover
was observed in the final clarifiers.
Comment:
Chemical Feed Yes No NA NE
Is containment adequate?
Is storage adequate?
Are backup pumps available?
Is the site free of excessive leaking?
Page#7
Permit:NC0024970
Inspection Date:02/25/2022
Owner - Facility:
Inspection Type:
McAlpine Creek WWTP
Compliance Evaluation
Chemical Feed Yes No NA NE
Comment:
Secondary Clarifier Yes No NA NE
Is the clarifier free of black and odorous wastewater?
Is the site free of excessive buildup of solids in center well of circular clarifier?
Are weirs level?
Is the site free of weir blockage?
Is the site free of evidence of short-circuiting?
Is scum removal adequate?
Is the site free of excessive floating sludge?
Is the drive unit operational?
Is the return rate acceptable (low turbulence)?
Is the overflow clear of excessive solids/pin floc?
Is the sludge blanket level acceptable? (Approximately ¼ of the sidewall depth)
The facility is equipped with sixteen (16) final clarifiers (6 – North Train and 10 – South
Train). All final clarifiers were in service except for one clarifier per train being
rehabbed.
Comment:
Pumps-RAS-WAS Yes No NA NE
Are pumps in place?
Are pumps operational?
Are there adequate spare parts and supplies on site?
Comment:
Filtration (High Rate Tertiary)Yes No NA NE
Type of operation:Down flow
Is the filter media present?
Is the filter surface free of clogging?
Is the filter free of growth?
Is the air scour operational?
Is the scouring acceptable?
Is the clear well free of excessive solids and filter media?
All nineteen (19) tertiary filters were in service.Comment:
Page#8
Permit:NC0024970
Inspection Date:02/25/2022
Owner - Facility:
Inspection Type:
McAlpine Creek WWTP
Compliance Evaluation
Disinfection-Liquid Yes No NA NE
Is there adequate reserve supply of disinfectant?
(Sodium Hypochlorite) Is pump feed system operational?
Is bulk storage tank containment area adequate? (free of leaks/open drains)
Is the level of chlorine residual acceptable?
Is the contact chamber free of growth, or sludge buildup?
Is there chlorine residual prior to de-chlorination?
Both chlorine contact chambers were in service.Comment:
De-chlorination Yes No NA NE
Type of system ?Liquid
Is the feed ratio proportional to chlorine amount (1 to 1)?
Is storage appropriate for cylinders?
# Is de-chlorination substance stored away from chlorine containers?
Are the tablets the proper size and type?
Aqueous sodium bisulfite is used for dechlorination.Comment:
Are tablet de-chlorinators operational?
Number of tubes in use?
Comment:
Flow Measurement - Effluent Yes No NA NE
# Is flow meter used for reporting?
Is flow meter calibrated annually?
Is the flow meter operational?
(If units are separated) Does the chart recorder match the flow meter?
The flow meter is calibrated twice per year and was last calibrated on 1/24/22 by CITI,
LLC.
Facility staff must ensure effluent flows account for the non-potable flows used on-site.
Comment:
Effluent Pipe Yes No NA NE
Is right of way to the outfall properly maintained?
Are the receiving water free of foam other than trace amounts and other debris?
If effluent (diffuser pipes are required) are they operating properly?
Page#9
Permit:NC0024970
Inspection Date:02/25/2022
Owner - Facility:
Inspection Type:
McAlpine Creek WWTP
Compliance Evaluation
Effluent Pipe Yes No NA NE
The effluent appeared clear with no floatable solids and foam (entrained air). The
foam dissipated prior to the Lancaster Highway bridge. The receiving stream did not
appear to be negatively impacted.
Comment:
Anaerobic Digester Yes No NA NE
Type of operation:Fixed cover
Is the capacity adequate?
# Is gas stored on site?
Is the digester(s) free of tilting covers?
Is the gas burner operational?
Is the digester heated?
Is the temperature maintained constantly?
Is tankage available for properly waste sludge?
The facility is equipped with eight (8) digesters and two (2) storage tanks (floating
cover). Seven (7) digesters and one storage tank were in service.
The facility continues to use the Combine Heat & Power facility using methane gas as
the fuel source.
Comment:
Solids Handling Equipment Yes No NA NE
Is the equipment operational?
Is the chemical feed equipment operational?
Is storage adequate?
Is the site free of high level of solids in filtrate from filter presses or vacuum filters?
Is the site free of sludge buildup on belts and/or rollers of filter press?
Is the site free of excessive moisture in belt filter press sludge cake?
The facility has an approved sludge management plan?
The facility is equipped with four (4) gravity thickeners (three in service) and six (6)
centrifuges (3 – thickening and 3 – dewatering). All thickening centrifuges and two (2)
dewatering centrifuges were in service.
The primary and waste activated sludges from the Sugar Creek WWTP are processed
at this facility.
Dewatered bio-solids are stored under cover and are land applied by a contracted
company (Synagro) under the authority of Permit No. WQ0000057.
Comment:
Standby Power Yes No NA NE
Is automatically activated standby power available?
Is the generator tested by interrupting primary power source?
Is the generator tested under load?
Page#10
Permit:NC0024970
Inspection Date:02/25/2022
Owner - Facility:
Inspection Type:
McAlpine Creek WWTP
Compliance Evaluation
Standby Power Yes No NA NE
Was generator tested & operational during the inspection?
Do the generator(s) have adequate capacity to operate the entire wastewater site?
Is there an emergency agreement with a fuel vendor for extended run on back-up
power?
Is the generator fuel level monitored?
The facility is equipped with six (6) backup generators. The generators are serviced
on a quarterly basis by a contracted company (Cummings).
Comment:
Page#11
NORTH CAROLINA 2022 303(D) LIST
Catawba River BasinLower Catawba
AU ID
AU NumberAU Name
Description
AU_LengthArea AU_UnitsClassification
McAlpine Creek (Waverly Lake)
667
11-137-9b
From SR 3356 to NC 51
6.3 FW MilesC
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 2000
McAlpine Creek (Waverly Lake)
668
11-137-9c
From NC 51 to NC 521
4.6 FW MilesC
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
McAlpine Creek (Waverly Lake)
666
11-137-9d
From NC 521 to North Carolina-South Carolina State Line
1.0 FW MilesC
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 2000
Twelvemile Creek
676
11-138
From source to North Carolina-South Carolina State Line
3.0 FW MilesC
PARAMETER IR CATEGORY CRITERIA STATUS REASON FOR RATING 303D YEAR
Fish Community (Nar, AL, FW)5 Exceeding Criteria Fair, Poor or Severe Bioclassification 2010
Sixmile Creek
691
11-138-3
From source to North Carolina-South Carolina State Line
8.8 FW MilesC
PARAMETER IR CATEGORY CRITERIA STATUS REASON FOR RATING 303D YEAR
Fish Community (Nar, AL, FW)5 Exceeding Criteria Fair, Poor or Severe Bioclassification 2006
Page 37 of 1926/7/2022 NC 2022 303d List- Approved by EPA 4/30/2022

1 MERCURY MINIMIZATION PLAN Rev. 02/02/2022

MERCURY MINIMIZATION PLAN
Charlotte Water (CLTWater) serves approximately 276,498 households and businesses in Mecklenburg
County that discharge wastewater directly to the sanitary sewer (Wastewater Performance Report, 2021).
Customers are categorized as either commercial or residential in the billing system. Dentists, once
considered the only major contributor of mercury to the wastewater collection system, have the potential
to pollute the sanitary sewer with waste from the installation or removal of dental amalgam. However,
other industries are also potential contributors of this pollutant. This Mercury Minimization Plan is an
outline to facilitate a minimization in the levels of mercury entering the sanitary sewer system. In the data
analysis for the wastewater system, the goal is to target areas of concern as the basin-specific data
experiences an upward trend in relation to the Baseline Study.
METHODOLOGY
The MMP focus is on the individual basin trends. The five wastewater plants operated by CLTWater are
Mallard Creek, McDowell Creek, Irwin Creek, Sugar Creek and McAlpine Creek wastewater treatment
plants. Additional monitoring sites are located strategically throughout the collection system. When
upward trends of five percent above the baseline influent data for the basin occur, further action may be
taken to minimize the potential impact of the pollutant on the ecosystem. The baseline was determined by
averaging three calendar years’ data for each plant. Some other industries, such as laboratories,
hospitals, schools and factories could affect the wastewater collection system with mercury. Although
they may not hold an SIU permit, an annual chemical inventory may be required if upward trends warrant
increased action.
THE PLAN
Mercury comes from a variety of sources. Identifying these sources is the key to a successful
minimization plan. Depending upon the data trends in each wastewater basin, an annual review of the
following steps will determine the level of action for the upcoming year:
1. The Assessment – Annual Report generated by CLTWater, including the removal rates for the
wastewater treatment plants.
2. Monitoring – Periodic wastewater data review for the wastewater treatment plants, continuous
industrial waste survey process, sampling and increased inspection frequencies as trends dictate.
3. Dental Amalgam Program – A dental amalgam plan developed by CLTWater in response to the
promulgation of 40 CFR 441. The plan outlines the general oversight of dental practices in
Mecklenburg county.
4. Educational Outreach - Oral and written communication to the community about findings and
increased efforts to reduce mercury pollution.
5. Internal Assessments – Including but not limited to, review of Spill Control Plans, Chemical Hygiene
Plans and safety for employees periodically in Laboratory Services.
For more information about mercury, please refer to the 2022 Mercury Assessment.

2 MERCURY MINIMIZATION PLAN Rev. 02/02/2022

THE ASSESSMENT
Annually, CLTWater performs an assessment of the potential contributors of mercury to the collection
system and publishes the findings. The assessment includes newly identified potential contributors, as
well as known contributors of any level of mercury to the wastewater collection system. Known
contributors that have a Significant Industrial User (SIU) permit limit should take the necessary actions
outlined in their permit if their discharge exceeds the permit limit for mercury. These facilities are
inspected once annually and the Compliance Specialist assigned to that industry should be notified if
changes in the chemical inventory or process have the potential to affect the wastewater effluent of the
facility. From the reported information, it can be determined if any changes need to be made to the permit
limits. Industries that hold an SIU permit should also respond to the wastewater survey provided them by
their designated Compliance Specialist once every five years and keep track of any chemicals that
contain mercury by performing a comprehensive chemical inventory, using Safety Data Sheets housed
onsite. The annual inspection sheet has one new question concerning mercury to keep the industry
mindful of the potential impact the pollutant could have on the collection system.
MONITORING
Based on data from 2021, CLTWater’s five wastewater plants currently average a 99.03% removal rate
for mercury from the influent stage of treatment to the effluent stage. The data from each wastewater
basin will be reviewed periodically for trending. If the data is in an upward trend for any of the five basins,
additional measures may be activated to curb those trends. These measures may include additional
inspections or sampling in the collection system to determine the contributors. Once it is determined the
level of contribution by the industries, then a plan of action may include methods of reducing the mercury
levels leaving the facility, implementation of Best Management Practices to prevent reoccurrence of the
pollutant discharge and monitoring onsite at the expense of the industry, as needed. To verify that the
efforts are working, a routine sampling program may be required for the facilities found to have elevated
levels of mercury in their wastewater effluent.
DENTAL AMALGAM PROGRAM

On July 14, 2017, the EPA promulgated 40 CFR Part 441. This rule requires dental offices that place
and/or remove amalgam to install an amalgam separator in accordance with the requirements in the rule,
to implement two best management practices, to submit a one-time compliance report to the POTW, and
to conduct on-going operation and maintenance of the amalgam separator and maintain associated
documentation and records.

CLTWater has developed a Dental Amalgam Plan to outline its general oversight of those dental
practices that operate in Mecklenburg county. CLTWater will be responsible for receiving, reviewing, and
retaining a One-Time Compliance Report (OTCR) submitted by users subject to rule 40 CFR Part 441.
CLTWater has developed a OTCR requesting all information required by the EPA. It also contains
additional questions asked by CLTWater.

A mass email with CLTWater’s expectations for dental dischargers along with an attached OTCR and
Cover Letter was sent to licensed dentists whose license was registered with a Mecklenburg county

3 MERCURY MINIMIZATION PLAN Rev. 02/02/2022

address. The list of licensed dentists was purchased from the NC Dental Licensing Board. A section for
“Dental Dischargers” has also been added to the CLTWater website. There customers can find additional
information about 40 CFR Part 441, a fillable copy of the OTCR, a link to the EPA Dental Effluent
Guidelines, and CLTWater pretreatment staff contact information.

CLTWater’s Enforcement Response Plan was updated to describe CLTWater’s response to instances of
noncompliance committed by dental dischargers. This update was approved by the Pretreatment,
Emergency Response, and Collection Systems Unit (PERCS) of the Division of Water Resources on
January 7, 2020.

EDUCATIONAL OUTREACH

On the mecknc.gov website CLTWater customers can find drop-off locations for common household
items that may contain mercury such as compact fluorescent lights (CFLs), old thermostats, button cell
batteries, car parts, and household appliances. There are four Recycling Centers across Mecklenburg
County. Items such as household appliances, compact fluorescent lights, and batteries can be brought to
the recycling centers. CLTWater customers may also find information concerning the proper disposal of
household waste by visiting the mecknc.gov website. Any household items found to contain mercury need
to go to the nearest drop-off location for disposal. These items should never be discharged to the sanitary
sewer system.

INTERNAL ASSESSMENT

CLTWater has several checks and balances in place to ensure it is doing all it can to prevent the
introduction of Mercury into our collection system. Four of the five Wastewater treatment plants disinfect
the wastewater with Ultraviolet light. When the UV bulbs are replaced, and if they are still under
manufacturer warranty they are returned to the manufacture (Xylem). If the bulbs are spent or no longer
under manufacturer warranty the bulbs are packaged and taken one of the four recycling centers located
in Mecklenburg county. Any fluorescent or CFL bulbs used by the plants are also taken to the recycling
center. The wastewater treatment plants have transitioned from using thermometers and manometers
that contain mercury. Property Management and Lab Services assisted the plants in the equipment
changeover. Each Plant has an Approved Spill Control Plan and Chemical Hygiene Plan in place.

Charlotte Water Laboratory Services Division analyzes over 200,000 wastewater and drinking water
samples annually. Lab Services has a contract with CHEMTRON Corporation. CHEMTRON is contacted
by Lab Services to collect and dispose of chemical hazards. Different areas within the lab use chemicals
for sample preservation and in instrumentation calibration standards. All heavy metals calibration
standards are picked up by CHEMTRON.

Lab Services uses rechargeable Lithium batteries for select pieces of analytical equipment. There has
been a recycling program set in place for the spent rechargeable and spent alkaline batteries. The
batteries will be stored in a marked container and stored until a drop-off date has been chosen. A
member of the Laboratory Services field staff will drop the batteries off for recycling at a Batteries Plus
location within the Charlotte area.

Lower Catawba River Basin – 2020 Nutrient Study
Final Report of the Field Program
September 2021
Prepared by Matthew S. Baumann, Ph.D.

Bureau of Water
303(d), Modeling & TMDL Section
Columbia, SC 29201

Technical Report No. 007-2021
Table of Contents
Overview of the 2020 Lower Catawba Study ................................................................................................ 1
Nutrient Study Project/Task Description ...................................................................................................... 2
Field Logistics ............................................................................................................................................ 2
Sensor Data ............................................................................................................................................... 5
Surface Parameters ............................................................................................................................... 5
Vertical Profile ...................................................................................................................................... 6
Continuous Monitoring ......................................................................................................................... 6
Fluorometer-Based Chlorophyll-a ............................................................................................................. 7
Cyanotoxins ............................................................................................................................................... 7
Water Quality ............................................................................................................................................ 7
Streams ................................................................................................................................................. 7
Lakes ..................................................................................................................................................... 7
Summary of Findings..................................................................................................................................... 8
Vertical Profile ........................................................................................................................................... 8
Continuous Monitoring ........................................................................................................................... 10
Fluorometer-Based Chlorophyll-a ........................................................................................................... 12
Cyanotoxins ............................................................................................................................................. 14
Water Quality .......................................................................................................................................... 15
Conclusion ................................................................................................................................................... 18
Acknowledgments ....................................................................................................................................... 18
Appendix A – Vertical Profile Section Graphs ............................................................................................. 19

List of Figures

Figure 1. Grab sampling site LWT-01 at the boat ramp immediately below Lake Wylie dam. .................... 3
Figure 2. Sampling sites near and within Fishing Creek Reservoir and Lake Wateree. Grab samples only
were collected at river site CW-016 (purple). Continuous monitoring systems were installed, and
grab samples were collected at sites LCR-04, LCR-02, LCR-03, CW-208, and CW-207B (blue). Grab
sampling only occurred at CW-231 (red). ........................................................................................ 4
Figure 3. Temperature (°C) section plot for CW-208 in the Dutchman Creek arm of Lake Wateree. The
vertical profile from 8/24/2020 (Julian Day 237) was lost due to an instrument software
malfunction. ..................................................................................................................................... 9
Figure 4. Dissolved oxygen (mg/L) section plot for CW-208 in the Dutchman Creek arm of Lake Wateree.
The vertical profile from 8/24/2020 (Julian Day 237) was lost due to an instrument software
malfunction. ..................................................................................................................................... 9
Figure 5. pH section plot for CW-208 in the Dutchman Creek arm of Lake Wateree. The vertical profile
from 8/24/2020 (Julian Day 237) was lost due to an instrument software malfunction. ............. 10
Figure 6. Average daily temperature at CW-208 in the Dutchman Creek arm of Lake Wateree. Data loss
occurred for June 4-8, 2020. .......................................................................................................... 11
Figure 7. Daily minimum and maximum recorded dissolved oxygen concentrations (mg/L) at CW-208 in
the Dutchman Creek arm of Lake Wateree. Data loss occurred for June 4-8, 2020. .................... 11
Figure 8. Hourly average dissolved oxygen concentrations (mg/L) for the April 14 through October 29,
2020, continuous monitoring record at CW-208 in the Dutchman Creek arm of Lake Wateree. . 12
Figure 9. Daily minimum and maximum recorded dissolved pH values at CW-208 in the Dutchman Creek
arm of Lake Wateree. Data loss occurred for May 13-25 and June 4-8, 2020. ............................. 12
Figure 10. Box plot summary of surface (0.3 m) total chlorophyll-a concentrations (µg/L) for each lake
station (n = 15). The red line denotes the 40 µg/L ecoregional total chlorophyll-a standard. ..... 13
Figure 11. Box plot summary of subsurface (1.5 m) total chlorophyll-a concentrations (µg/L) for each
lake station (n = 15). ...................................................................................................................... 14
Figure 12. Box plot summary of total phosphorus concentrations (mg/L) measured at each stream and
lake station. The red line denotes the 0.06 mg/L lake ecoregional total phosphorus standard. .. 16
Figure 13. Box plot summary of total nitrogen concentrations (mg/L) measured at each stream and lake
station. The red line denotes the 1.5 mg/L lake ecoregional total nitrogen standard. ................. 17
Figure 14. Box plot summary of total organic carbon concentrations (mg/L) measured at each stream
and lake station. ............................................................................................................................. 18

List of Tables
Table 1. Field program site coordinates and descriptions. ........................................................................... 3
Table 2. Range (minimum and maximum) for each primary field parameter over the 4/7/2020 –
10/20/2020 period at the stream and lake sites. ............................................................................ 5
Table 3. Range (minimum and maximum) for additional field parameters at the lake sites surface over
the 4/7/2020 – 10/20/2020 study period. ....................................................................................... 6
Table 4. Total chlorophyll-a summary statistics for each lake station and depth along with the percent of
observations in which the surface (0.3 m) concentration is greater than the subsurface (1.5 m)
measurement. Average is presented as ± 1σ. All total chlorophyll units in µg/L. ........................ 13
Table 5. Microcystins cyanotoxin summary statistics for each lake station. Samples for microcystins were
collected every other field sampling trip at the surface (0.3 m). Average is presented as ± 1σ. All
total microcystins concentrations in µg/L. .................................................................................... 15

Executive Summary
During 2020, South Carolina Department of Health and Environmental Control (DHEC) collected water
quality data from two stream sites and six lake sites in the Lower Catawba River Basin located in north-
central South Carolina. The field sampling program spanned early April through the end of October and
builds on studies conducted in previous years by DHEC and stakeholder partners. This program was
designed to address specific questions that remained from studies in prior years including further
resolving the seasonal cycle of physical conditions and progression in phototroph ecology in the system
and to enhance chemical and physical understandings at key locations in the basin.

The 2020 program objective was achieved using a series of five monitoring systems in Lake Wateree and
Fishing Creek Reservoir to continuously record physical/hydrographic parameters and biological
responses (sensor-based chlorophyll-a and phycocyanin) coupled with biweekly water quality sampling at
these lake sites as well as three other strategic locations (one in upper Lake Wateree and two in the
Catawba River). The data collected as part of this study will provide insights into the mechanistic links
between physical conditions and nutrients and algal responses such as phytoplankton biomass and toxin
production.
This report discusses the successes and challenges of the field program and briefly summarizes data
collected as part of the continuous monitoring and biweekly grab sample project components. Generally,
all field program objectives were achieved as nearly all targeted data were successfully collected. Early in
the field season, technical challenges associated with new equipment led to interruptions in the
continuous records at three locations. The continuous records at these sites were more complete from
early July through the end of record as issues were resolved.
Over the course of the field program:
• Surface temperatures generally exceeded 30°C by mid-July and persisted through mid-September
based on vertical profile and continuous monitoring data. Apparent temperature-based
stratification was variable based on the area of the lake.
• The upstream lake stations in Lake Wateree exhibited the lowest total chlorophyll-a
concentrations and the dissolved oxygen concentrations and pH values in the water column in
this area showed little response to algal growth.
• The highest total chlorophyll-a concentrations were measured in the Dutchman Creek arm of Lake
Wateree. Elevated upper water column dissolved oxygen and pH were also observed in the lake
arm.
• Generally, total chlorophyll-a concentrations were higher at 1.5 m than at the surface (0.3 m).
• Nutrient concentrations (total phosphorus and total nitrogen) in water discharged from Lake
Wylie were on average lower than other sites (stream and lake) sampled as part of this project.
• Despite returning the highest total chlorophyll-a concentrations, average total phosphorus and
total nitrogen in the Dutchman Creek arm were the lowest measured among the lake sites.
Average total organic carbon concentration was highest in this lake arm.

1

Overview of the 2020 Lower Catawba Study
The Lower Catawba River Basin includes the watershed drainage from the tailrace at Lake Wylie in Fort
Mill, South Carolina, to the tailrace at Lake Wateree in Kershaw County, South Carolina. The system is one
of the major watersheds for the city of Charlotte, North Carolina, and its south suburbs including rapidly
growing York County, South Carolina. More than 30 ambient monitoring locations in the Lower Catawba
are included in the State’s draft 2018 303(d) list as impaired for total phosphorus, total nitrogen, and/or
chlorophyll-a. In addition, blooms of planktonic Microcystis and colonies of Lyngbya wollei, a filamentous,
mat-forming algae are commonly present in Lake Wateree during the hot summer months. These
cyanobacteria produce toxins known to cause swimmer’s itch, respiratory problems, and taste and odor
issues in drinking water.
In 2016, using an updated version of the WARMF model, South Carolina Department of Health and
Environmental Control (DHEC) determined and proposed preliminary total phosphorus and total nitrogen
load reductions for point and nonpoint sources as the starting point for Total Maximum Daily Loads
(TMDLs). The load reductions included a 66 percent cut in phosphorus and a 55 percent cut in nitrogen
from wastewater sources. Reductions from stormwater and human nonpoint sources varied by location,
up to 50 percent. DHEC presented these results to stakeholders and proposed that stakeholders conduct
an allocation process to determine individual allocations most effectively. DHEC provided a phosphorus
allocation tool to assist the process.
In response, the dischargers in the Lower Catawba asked DHEC for time to collect additional data and
develop more detailed modeling and develop site-specific numeric nutrient (total nitrogen and total
phosphorus) and chlorophyll-a standards for the lakes. The standards would be used to develop TMDLs
aimed at addressing water quality impairments impacting designated uses. The stakeholders and the
National Council for Air and Stream Improvement (NCASI) developed an approved Quality Assurance
Project Plan (QAPP) and conducted extensive monitoring in the Catawba basin in 2017 and 2018. The
group also initiated a facilitated model review group to select suitable models to support criteria and
TMDL development.
In 2019, DHEC Bureau of Water (BOW) 303d, TMDL and Modeling group (TMDL group) implemented the
Lower Catawba River Basin – Stream and Lake Nutrient Water Quality Study (Nutrient Study) as well as
wet-weather watershed studies to produce an enhanced suite of environmental data. The results of these
studies may be found in DHEC Bureau of Water Technical Report Nos. 009-2020 (Nutrient Study) and 014-
2020 (Wet Weather Studies).1,2
As part of the Nutrient Study, BOW collected biweekly water quality data from six stream sites and 11 lake
sites from mid-April through the end of October 2019. Broadly, the objectives of the Nutrient Study were
to quantify nutrient loadings from the prevalent land use types in the basin and to resolve the relationship
between physical and chemical conditions and ecological responses in Fishing Creek Reservoir and Lake

1South Carolina Department of Health and Environmental Control. 2020. Lower Catawba River Basin – Stream and
Lake Nutrient Water Quality Study, Final Report of the 2019 Study. Bureau of Water Technical Report No. 009-2020.
February 2020.

2South Carolina Department of Health and Environmental Control. 2020. Phase 1-Wet Weather Data Analysis.
Bureau of Water Technical Report No. 014-2020. June 2020.
2

Wateree. Samples were collected for 18 unique chemical water quality parameters in the streams and at
multiple depths in the lakes. In addition, total chlorophyll-a and photosynthetic pigment samples along
with sensor-based vertical profiles for physical parameters were collected in the lakes. Monitoring
systems to continuously record physical parameters at the surface were also deployed at two locations:
one in the mid-lake area of Fishing Creek Reservoir and one in Lake Wateree off the Dutchman Creek lake
arm. Further, DHEC partnered with EPA to 1) conduct algal growth potential tests to investigate nutrient
limitation on the phytoplankton community, 2) quantify sediment oxygen demand and nutrient fluxes
between sediments and the water column, and 3) install two additional continuous monitoring systems
at strategic locations in Lake Wateree. DHEC also collaborated with NCASI to quantify grain size and
organic carbon content in Lake Wateree sediments. Lastly, DHEC and Coastal Carolina University installed
a weather station at Wateree State Park to support modelling efforts.
In 2019 and into the winter of 2020, BOW conducted two watershed studies aimed at characterizing
nutrient loadings to the Catawba River and lake during wet-weather events in five watersheds of varying
land use types. Nutrient loadings during storm events, particularly at the ‘first flush’ of the event, can be
significant due to release of accumulated pollutant mass at the surface and in soil pores associated with
high energy runoff of heavy rainfall. Currently, there are no nutrient loading data for the Lower Catawba
associated with the wet-weather events. An understanding of these loadings during storm events
enhances watershed modeling capability and robustness through verification of nutrient loading export
mechanisms.
In 2020, the TMDL group conducted the Lower Catawba River Basin – 2020 Nutrient Study (2020 Lake
Program) program to address specific questions that remained including further resolving the seasonal
cycle of physical conditions and progression in phototroph ecology in the system and to enhance chemical
and physical understandings at three key locations in the basin that represent important entry points into
the system. The new data will be coupled with previous water quality studies by the dischargers and
DHEC’s ambient water quality monitoring data to develop new watershed, lake hydrodynamic, and lake
water quality models to assist in informing site-specific numeric criteria for the Lower Catawba system.
The 2020 program objective was achieved using a series of five monitoring systems in Lake Wateree and
Fishing Creek Reservoir to continuously record physical/hydrographic parameters and biological
responses (sensor-based chlorophyll-a and phycocyanin) coupled with biweekly water quality sampling at
these lake sites as well as three other strategic locations (one in upper Lake Wateree and two in the
Catawba River). The data collected as part of this study will provide insights into the mechanistic links
between physical conditions and nutrients and algal responses such as phytoplankton biomass and toxin
production. Together with the results of the earlier studies, these links will help establish site-specific
nutrient and chlorophyll-a criteria that are protective of the lakes’ designated uses.
Nutrient Study Project/Task Description
Field Logistics
The 2020 Lake Program spanned 30 weeks from the end of March through the end of October 2020. The
study focused on a series of eight strategic locations in the Lower Catawba River Basin to meet the
objectives described above (Table 1, Figures 1,2):

3

1. LWT-01 – Lake Wylie tailrace immediately below dam (stream site)
2. CW-016 – Catawba River at Highway 9 bridge (stream site)
3. LCR-04 – Fishing Creek Reservoir off Bear Creek arm (lake site)
4. CW-231 – Lake Wateree headwater below Cedar Creek Reservoir dam (lake site)
5. LCR-02 – Lake Wateree upstream of Wateree Creek arm (lake site)
6. LCR-03 – Lake Wateree off Dutchman Creek arm (lake site)
7. CW-208 – Dutchman Creek arm of Lake Wateree (lake site)
8. CW-207B – Mid-lake Lake Wateree (lake site)
Table 1. Field program site coordinates and descriptions.
Station ID Lat./Long. County Site Description
Stream Sites
LWT-01 35.0213 / -81.0038 York Lake Wylie Tailrace Boat Landing
CW-016 34.7083 / -80.8676 Chester Catawba River at SC-9 (Fort Lawn)
Lake Sites
LCR-04 34.6203 / -80.8862 Lancaster Fishing Creek Reservoir off Bear Creek arm
CW-231 34.5365 / -80.8749 Lancaster Lake Wateree headwater below Cedar
Creek Reservoir dam
LCR-02 34.4882 / -80.9001 Fairfield/Lancaster Lake Wateree upstream of Wateree Creek
(near RL-11040)
LCR-03 34.4260 / -80.8460 Fairfield/Kershaw Lake Wateree off Dutchmans Creek arm
CW-208 34.4222 / -80.8668 Fairfield Lake Wateree at S-20-101 11 miles east
northeast of Winnsboro
CW-207B 34.4039 / -80.7827 Fairfield Mid-channel Lake Wateree at end of S-20-
291

Figure 1. Grab sampling site LWT-01 at the boat ramp immediately below Lake Wylie dam.
4

Figure 2. Sampling sites near and within Fishing Creek Reservoir and Lake Wateree. Grab samples only were collected at river site
CW-016 (purple). Continuous monitoring systems were installed and grab samples were collected at sites LCR-04, LCR-02, LCR-03,
CW-208, and CW-207B (blue). Grab sampling only occurred at CW-231 (red).
Biweekly grab sampling was conducted at all sites and continuous monitoring systems were installed at
five lake locations (LCR-04 in Fishing Creek Reservoir and LCR-02, LCR-03, CW-208, and CW-207B in Lake
Wateree). Continuous monitoring systems were serviced every other week. Surface (nominal 0.3 m) grab
sample parameters included:
• 5-day biochemical oxygen demand (BOD5; stream sites only),
• Turbidity,
• Ammonia-nitrogen,
• Nitrate/nitrite-nitrogen,
• Total Kjeldahl Nitrogen,
• Total phosphorus,
• Orthophosphate,
• Total suspended solids,
• Total and filtered total organic carbon,
• Total chlorophyll-a (surface and 1.5 m, lake sites only), and
• Cyanotoxins (microcystins, lake site only, approximately monthly)
Field sensor measurements were recorded at each grab sample site (all sites) along with vertical profiles
and photosynthetically active radiation penetration were collected at each lake site:
• Water temperature,
• Dissolved oxygen,
• pH,
• Turbidity,
• Specific conductance,
• Chlorophyll-a fluorescence (lake sites only), and
• Phycocyanin fluorescence (lake sites only)
5

Continuous monitoring systems recorded surface measurements (0.5-1.0 m depending on the system) at
15 to 30-minute intervals at the five lake locations. Surface measurements are the same as the field sensor
measurements listed above. An attempt was made to collect continuous nitrate data at three locations
(LCR-04, LCR-03, and CW-207B), however, technical issues related to Ott EcoN instrument power
consumption curtailed the records for this parameter. As such, continuous nitrate data will not be
presented here. Further, technical issues related to calibration and manufacturer failings of the In-Situ
Aqua Troll 600 phycocyanin sensors used at the same locations limited the usefulness of these
measurements and will not be presented here.
Sensor Data
Surface Parameters
Surface physical parameters were collected at a depth of 0.3 m at each stream and lake site using a
calibrated Hydrolab DS5X (streams) and YSI EXO2 (lakes). Sampling was conducted from mid-morning
through early afternoon (09:00-14:00). Routine physical parameters included pH (SU), optical dissolved
oxygen (DO, mg/L), water temperature (°C), specific conductance (µS/cm) (Table 2)
Table 2. Range (minimum and maximum) for each primary field parameter over the 4/7/2020 – 10/20/2020 period at the stream
and lake sites.
Station Field pH
(SU)
Field DO
(mg/L)
Water Temp.
(°C)
Spec Cond.
(µS/cm)
Streams
LWT-01 5.63 - 7.50 5.12 - 8.91 17.2 - 29.4 55.0 - 83.0
CW-016 6.85 - 7.65 6.72 - 8.43 16.8 - 30.5 68.7 - 136
Lakes
LCR-04 6.96 - 9.22 7.27 - 11.96 19.09 - 31.30 73.0 - 115.1
CW-231 6.86 - 7.31 6.82 - 9.11 17.98 - 30.05 73.3 - 115.2
LCR-02 6.85 - 7.88 7.21 - 9.43 19.16 - 31.67 73.8 - 115.9
LCR-03 7.00 - 9.10 7.18 - 11.61 19.36 - 32.44 74.0 - 121.3
CW-208 7.44 - 9.27 7.23 - 12.12 19.78 - 32.45 79.6 - 111.3
CW-207B 7.07 - 9.23 7.03 - 11.80 20.07 - 32.33 72.4 - 116.1

An expanded suite of surface measurements was collected at each lake site including sensor-based
chlorophyll-a (µg/L) and phycocyanin (µg/L) (Table 3). In addition, upper water column features were
measured such as penetration depth of photosynthetically active radiation (PAR, 400-700 nm wavelength,
μmol m-2 s-1) using a LI-COR light meter and a LI-1400 data logger, water clarity expressed as secchi depth
(m), and turbidity (FNU). PAR depth was determined as the depth in which PAR decays to 1% of its ambient
value. The chlorophyll-a and phycocyanin maximums were determined from the vertical profile downcast
and described as either a maximum depth or vertical band where pigment fluorescence was highest. YSI
EXO2 sensor-based chlorophyll-a and phycocyanin measurements should be viewed relatively and
compared only with 2019 Nutrient Study data. Calibration protocols for the EXO Total Algae sensors were
changed to be more consistent with manufacturer recommendations prior to the upper Lake Murray field
study in 2021.
6

Table 3. Range (surface minimum and maximum) for additional field parameters at the lake sites over the 4/7/2020 – 10/20/2020
study period.
Station Chl-a (µg/L) Chl-a Max
Depth (m)
Phycocyanin
(µg/L)
Phycocyanin
Max Depth (m)
PAR Depth
(m)
Secchi Depth
(m)
Turbidity
(FNU)
LCR-04 1.94 - 18.23 0.3 - 1.75 0 - 6.87 0.3 - 0.3 1.5 - 4.7 0.4 - 0.9 4.30 - 52.45
CW-231 0 - 5.27 0.3 - 0.3 0 - 1.50 0.3 - 0.3 1.1 - 3.0 0.3 - 0.7 7.62 - 198.09
LCR-02 0.18 - 6.69 0.3 - 1.0 0 - 1.74 0.3 - 0.3 1.3 - 2.7 0.3 - 0.7 5.71 - 154.87
LCR-03 2.60 - 18.63 0.3 - 1.75 0 - 5.03 0.3 - 1.75 1.3 - 3.1 0.4 - 0.9 5.90 - 81.37
CW-208 5.62 - 19.50 0.3 - 1.5 0 - 9.52 0.3 - 1.5 1.6 - 3.1 0.5 - 0.8 4.50 - 38.94
CW-207B 0.90 - 13.45 0.3 - 2.0 0 - 5.63 0.3 - 2.0 1.7 - 4.3 0.4 - 1.1 3.02 - 25.49

Vertical Profile
Vertical profiles were collected at each lake site visit using the YSI EXO2. The casts were conducted
manually, but data were logged by the instrument every second. The sonde was gradually lowered
through the water column (downcast) until contact was made with the lake bottom and then retrieved at
a similar rate. An Excel tool was created to process raw vertical profile data. The tool extracts the downcast
from the profile record by identifying when instrument descent was initiated and when retrieval began
after contacting the lake bottom. The bottom depth for the profile could be manually adjusted to remove
the effects of sediment resuspension. The program then averaged the downcast data in half meter
intervals. Eight parameters were processed for each profile: water temperature, DO concentration, DO
percent saturation, pH, turbidity, specific conductance, chlorophyll-a concentration, and phycocyanin
concentration.
In total, 86 vertical profiles were collected as part of the 2020 Lake Program. Fifteen profiles were targeted
at each site. One profile was lost at CW-231, LCR-03, CW-208, and CW-207B on 8/24/2020 due to an
instrument software issue. Because profiles are collected on an approximately biweekly schedule, the
data can be used to illustrate the evolution of the water column over the course of the field program, but
do not capture diel variability.
Continuous Monitoring
Continuous monitoring systems were deployed at five of the six lake sites (CW-231 excluded) from
4/8/2020 through the end of October 2020. Each deployment was approximately two weeks in duration
and data were recorded at 15- or 30-minute intervals depending on the instrument used. YSI EXO2s (15-
minute recording interval) were deployed at sites LCR-02 and CW-208 and Hydrolab DS5Xs (30-minute
recording interval) were installed at LCR-04, LCR-03, and CW-207B.
Early in the field season, technical challenges associated with new equipment led to interruptions in the
continuous records, particularly at LCR-04, LCR-03, CW-207B. However, end verifications for the primary
variables (DO, pH, and specific conductance) were largely successful. A complete end of deployment
verification record is stored in the SharePoint Field Log. The following list summarizes end deployment
verifications, equipment challenges, and lessons learned:

7

• There are data gaps over the first few months at LCR-04, LCR-03, and CW-207B due to battery
strength and data logging/telemetry issues associated with new remote sensing buoys installed
at these locations. The buoys were removed in July and the records were more complete in the
second half of the field program.
• Towards the middle of the campaign, the DO sensors on Hydrolab DS5Xs occasionally began failing
for periods of time (3-6 hours) midday. These failings typically occurred when DO was highest in
the daily cycle and was due to flaking off of the coating on the sensor DO cap. Gentle care,
frequent inspection, and replacing the DO cap as necessary is recommended to avoid data loss.
• One DO verification failed for an EXO2 at CW-208 in May (Series 2). The record was not
immediately discarded as it tracked well with concurrent pH record.
• The EXO2 pH modules failed in May and replacements arrived in June. Two Series 3 pH records at
LCR-02 and CW-208 were lost. In-Situ Aqua Troll 600 instruments were used to bridge the gap in
pH records until EXO2 replacement modules arrived.
• A conductivity sensor failed on a Hydrolab DS5X H4472 and was replaced.
Fluorometer-Based Chlorophyll-a
A total of 165 lake samples were collected for fluorometer-based total chlorophyll-a. Samples were
collected at the surface (0.3 m) and at 1.5 m at all lake sites except CW-231 where surface only samples
were collected. No samples were lost.
Cyanotoxins
Samples for microcystins analysis were collected at the surface of each lake site every other field
sampling event therefore on an approximately monthly schedule. A total of 48 samples were collected
and no samples were lost.
Water Quality
Grab samples for water quality occurred biweekly from 4/7/2020-10/20/2020. Access Analytical and
Rogers and Calcott were used for the first four sampling events (4/7, 4/21, 5/5, and 5/19). The DHEC
Central Laboratory analyzed samples from 6/2 through the end of the project.
Streams
Each stream site was sampled 15 times over the course of the project. Each stream station satisfied the
completeness data quality indicator (DQI) as no visits were missed because of human error. Completeness
for each station, as assessed by sample opportunities, is determined to be 100%. Further, the project
operated under a biweekly sampling schedule, which ensured that the samples collected at each site were
evenly distributed across the study timeframe removing any bias towards a specific period of the season.
All stream laboratory water quality samples were successfully analyzed except for two ammonia samples
at each site due to instrument failure at the Central Laboratory.
Lakes
Each lake site was sampled 15 times during the field program. Completeness is determined to be 100% as
no sample event was omitted due to field team decision or error. As with the stream component, lake
sampling followed a biweekly schedule and samples were evenly distributed over the course of the study.
All lake laboratory water quality samples were successfully analyzed except for two ammonia samples at
each site due to instrument failure at the Central Laboratory.
8

Summary of Findings
The following summary represents a brief discussion of high-level observations of keystone parameters
investigated as part of the 2020 Lower Catawba Nutrient Study. It is not meant to be exhaustive of all
data collected during the study. The discussion centers on broad features in the vertical and continuous
profile records at CW-208 in the Dutchman Creek arm of Lake Wateree and on summary statistics for
grab sample total chlorophyll-a, cyanotoxins (microcystins), total phosphorus, total nitrogen, and total
organic carbon for all sites.
Vertical Profile
Section graphs for temperature, dissolved oxygen, pH, temperature, specific conductance, and
chlorophyll-a for each station are presented in Appendix A. The plots were interpolated from the 14 or
15 vertical profiles collected on a biweekly basis at each station. Because the plots are collected at
approximately two-week intervals at roughly the same time of day, the interpolated data illustrate the
seasonal, week over week, evolution of the water column at each site for physical and biological
parameters.
Section plots for temperature, dissolved oxygen, and pH for station CW-208 located in the Dutchman
Creek arm of Lake Wateree are presented in Figures 3-5. Surface water temperature reached a
maximum of ~32.5°C in mid- to late July. At this point of the season, the water column appeared to
demonstrate some thermal stratification (Figure 3), which is supported by enhanced dissolved oxygen
concentrations and pH levels near the surface relative to subsurface measurements (Figures 4 and 5).
Dissolved oxygen concentrations in bottom waters decreased to less than 2 mg/L during this period.
These conditions persisted for at least a month; however, it is not clear if these conditions extended
through late August as the 8/24/2020 profile was lost. Similar features occurred at the mid-lake stations
(LCR-04, LCR-03, and CW-207B; Appendix A) and coincided with a period of low rainfall in the local area
(0.11 inches (2.8 mm) for July and August, PRISM Climate Group).

9

Figure 3. Temperature (°C) section plot for CW-208 in the Dutchman Creek arm of Lake Wateree. The vertical profile from
8/24/2020 (Julian Day 237) was lost due to an instrument software malfunction.

Figure 4. Dissolved oxygen (mg/L) section plot for CW-208 in the Dutchman Creek arm of Lake Wateree. The vertical profile from
8/24/2020 (Julian Day 237) was lost due to an instrument software malfunction.

4/9/2020 5/29/2020
7/18/2020
9/6/2020 10/26/2020
4/9/2020 5/29/2020
7/18/2020
9/6/2020 10/26/2020
10

Figure 5. pH section plot for CW-208 in the Dutchman Creek arm of Lake Wateree. The vertical profile from 8/24/2020 (Julian
Day 237) was lost due to an instrument software malfunction.

Continuous Monitoring
Continuous monitoring of surface temperature indicated a gradual rise from April through mid-July to a
maximum daily average of 32.3°C on July 17, 2020 at CW-208 in the Dutchman Creek arm of Lake
Wateree (Figure 6). Temperatures remained above 29°C until the middle of September before
decreasing to 12-23°C for the remainder of the monitoring period.
During July and August, daily minimum and maximum dissolved oxygen concentrations were generally
lower than in the April through June and mid-September through the end of October periods in the
Dutchman Creek arm (Figure 7). The mid-summer decrease in dissolved oxygen occurred during the
period of warmest ambient temperatures (Figure 6). The observed decrease in daily minimum dissolved
oxygen is more pronounced than for the daily maximum concentration as daily differences (daily
maximum – daily minimum) were larger during the mid-summer period. For the April through October
monitoring period, dissolved oxygen appeared to mirror the pattern of daytime photosynthesis and
overnight respiration (Figure 8). On average, the 0800 hour demonstrated the lowest dissolved oxygen
concentration (8.54 mg/L) and 1700 produced the highest concentration (10.58 mg/L).
The Dutchman Creek arm consistently demonstrated elevated pH over the monitoring period. The
maximum daily pH exceeded 8.5 on 161 of the 181-day record (89%). Further, the minimum daily pH
exceeded 8.5 on 18 days, an exceedance of the standard of 10%. The average difference between daily
minimum and maximum pH values was 1.42 (range: 0.13-2.52).
4/9/2020 5/29/2020
7/18/2020
9/6/2020 10/26/2020
11

Figure 6. Average daily temperature at CW-208 in the Dutchman Creek arm of Lake Wateree. Data loss occurred for June 4-8,
2020.

Figure 7. Daily minimum and maximum recorded dissolved oxygen concentrations (mg/L) at CW-208 in the Dutchman Creek arm
of Lake Wateree. Data loss occurred for June 4-8, 2020.
15
17
19
21
23
25
27
29
31
33
35
4/1/2020 5/1/2020 5/31/2020 6/30/2020 7/30/2020 8/29/2020 9/28/2020 10/28/2020TEMPERATURE (°C)Average Daily Temperature
4
6
8
10
12
14
16
4/1/2020 5/1/2020 5/31/2020 6/30/2020 7/30/2020 8/29/2020 9/28/2020 10/28/2020DISSOLVED OXYGEN (MG/L)Daily Minimum and Maximum Dissolved Oxygen
Min. Daily DO Max. Daily DO
12

Figure 8. Hourly average dissolved oxygen concentrations (mg/L) for the April 14 through October 29, 2020, continuous
monitoring record at CW-208 in the Dutchman Creek arm of Lake Wateree.

Figure 9. Daily minimum and maximum recorded dissolved pH values at CW-208 in the Dutchman Creek arm of Lake Wateree.
Data loss occurred for May 13-25 and June 4-8, 2020.
Fluorometer-Based Chlorophyll-a
Grab sample total chlorophyll-a distribtions were variable across the system and throughout the study.
For the mid-lake stations (LCR-03, LCR-04, CW-208, and CW-207B), the highest average surface total
choloropyll-a concentration occurred in early April (31.5 µg/L on 4/7/2020). At these stations, average
surface total chlorophyll-a was at least 25 µg/L for five consecutive summer sampling events (6/29, 7/13,
7/27, 8/10, and 8/24/2020). Of these stations, CW-208 demonstrated the highest field program average
surface total chlorophyll-a (32.4 µg/L), followed sequentially by CW-207B (21.7 µg/L), LCR-03 (18.5 µg/L),
and LCR-04 (17.7 µg/L) (Table 4). Three of the 15 (20%) surface values at CW-208 exceed the 40 µg/L
ecoregional standard (Figure 10). Total chlorophyll-a concentrations were typically greater at 1.5 m
6
7
8
9
10
11
12
DISSOLVED OXYGEN (MG/L)Hourly Average Dissolved Oxygen
6.0
6.5
7.0
7.5
8.0
8.5
9.0
9.5
10.0
4/1/2020 5/1/2020 5/31/2020 6/30/2020 7/30/2020 8/29/2020 9/28/2020 10/28/2020PH (SU)Daily Minimum and Maximum pH
Min. Daily pH Max. Daily pH
13

compared to the 0.3 m surface value (Figure 11). Specifically, the surface concentration was greater than
the 1.5 m value 27% of the time at CW-208 and LCR-03 and only 20% of the time at LCR-04 and CW-207B
(Table 4).
Table 4. Total chlorophyll-a summary statistics for each lake station and depth along with the percent of observations in which
the surface (0.3 m) concentration was greater than the subsurface (1.5 m) measurement. Average is presented as ± 1σ. All total
chlorophyll units in µg/L.
Station Depth (m) Avg. T. Chl-a Minimum Maximum n Surface > 1.5 m
LCR-04 0.3 17.7 ± 8.8 4.6 32.7 15 20% 1.5 18.1 ± 9.2 5.4 34.2 15
CW-231 0.3 6.0 ± 2.2 2.5 11.1 15 -
LCR-02 0.3 7.4 ± 5.2 3.1 23.9 15 13% 1.5 8.6 ± 4.5 4.2 18.1 15
CW-208 0.3 32.4 ± 7.7 17.7 45.0 15 27% 1.5 35.4 ± 9.2 19.8 47.1 15
LCR-03 0.3 18.5 ± 12.1 4.6 40.7 15 27% 1.5 20.4 ± 15.1 5.7 56.3 15
CW-207B 0.3 21.7 ± 8.0 7.7 37.8 15 20% 1.5 24.8 ± 10.0 8.0 48.5 15

Figure 10. Box plot summary of surface (0.3 m) total chlorophyll-a concentrations (µg/L) for each lake station (n = 15). The red line
denotes the 40 µg/L ecoregional total chlorophyll-a standard.
14

Figure 11. Box plot summary of subsurface (1.5 m) total chlorophyll-a concentrations (µg/L) for each lake station (n = 15).

Cyanotoxins
Microcystins concentrations at the open-lake stations were generally low and below the United States
Environmental Protection Agency recreational health advisory value and DHEC recreational standard of 8
µg/L.3,4 These samples were collected routinely at open water sites as part of the 2020 field program.
Cyanotoxin concentrations are typically higher within blooms of toxin producing cyanobacteria and in
coves or nearshore environments where macrophyte algae tend to accumulate. For more information
related to cyanotoxin distributions within South Carolina waters, refer to DHEC Bureau of Water Technical
Report No. 001-2021.5

3U.S. Environmental Protection Agency. 2019. Recommended Human Health Recreational Ambient Water Quality
Criteria or Swimming Advisories for Microcystins and Cylindrospermopsin. U.S. Environmental Protection Agency,
Office of Water, EPA- 822-R-19-001.
4South Carolina Department of Health and Environmental Control. Regulations 61-68 Water Classifications and
Standards.

5South Carolina Department of Health and Environmental Control. 2021. 2019 South Carolina Cyanotoxin
Distribution Project. Bureau of Water Technical Report No. 001-2021. March 2021.
15

Table 5. Microcystins cyanotoxin summary statistics for each lake station. Samples for microcystins were collected every other
field sampling trip at the surface (0.3 m). Average is presented as ± 1σ. All total microcystins concentrations in µg/L.
Station Avg. Microcystins Minimum Maximum n
LCR-04 0.074 ± 0.027 0.029 0.110 8
CW-231 0.080 ± 0.037 0.045 0.150 8
LCR-02 0.060 ± 0.030 0.018 0.097 8
CW-208 0.117 ± 0.063 0.062 0.253 8
LCR-03 0.066 ± 0.036 0.013 0.131 8
CW-207B 0.080 ± 0.038 0.035 0.148 8

Water Quality
The water quality data collected as part of this study will be used to support various components of the
watershed loading and lake water quality models. The following discussion summarizes the results for
total phosphorus (TP) and total nitrogen (TN), two nutrient parameters regulated in lakes by the State,
as well as total organic carbon (TOC). Note that TN is not explicitly measured but reported as the sum of
Total Kjeldahl Nitrogen (TKN, sum of ammonia/ammonium and organic nitrogen) and nitrate/nitrite.
BOW also engaged with Duke Energy Company to conduct split sampling at a series of strategic locations
throughout the basin as a measure of laboratory comparability as part of this project. The results of that
comparison study are presented in DHEC Bureau of Water Technical Report No. 008-2021.6
The lowest average concentrations for TP, TN, and TOC were measured at the tailrace of Lake Wylie
(LWT-01). The downstream Catawba River site, CW-014, demonstrated nutrient concentrations similar
to the lake stations. At the lake stations, average surface TP concentrations range from 0.040 mg/L to
0.54 mg/L (Figure 12). Average surface TN concentrations ranged 0.69 mg/L to 1.09 mg/L (Figure 13).
The lowest average concentrations for both TP and TN occurred at CW-208 in the Dutchman Creek arm
where the highest average total chlorophyll-a concentation was observed. Average lake TOC
concentrations ranged from2.76 mg/L to 3.55 mg/L (Figure 14) with the highest average value occuring
at CW-208.
This disucssion centered on CW-208 as a case study within the project. Notable features observed at this
station include:
• Surface water temperature reached of maximum of ~32.5°C in mid- to late July; possible
thermal stratification at this point in the season which is supported.
• Enhanced dissolved oxygen concentrations and pH levels observed near the surface in mid-July.
• Dissolved oxygen concentrations in bottom waters decreased to less than 2 mg/L in mid-July
through at least mid-August.
• Daily minimum and maximum dissolved oxygen concentrations were generally lower in July and
August than in the April through June and mid-September through the end of October periods.
• The lake arm consistently demonstrated elevated pH over the monitoring period.
• Dutchman Creek demonstrated the highest field program average surface total chlorophyll-a.

6 South Carolina Department of Health and Environmental Control. 2021. Catawba Basin Split Nutrient Study and
Comparability Report. Bureau of Water Technical Report No. 008-2021. September 2021.
16

• Average chlorophyll-a concentration at 1.5 m was higher than at the surface.
• The lowest average TP and TN concentrations were observed at CW-208.
• Dutchman Creek arm demonstrated the highest average TOC concentration of the lake stations.

Figure 12. Box plot summary of total phosphorus concentrations (mg/L) measured at each stream and lake station. The red line
denotes the 0.06 mg/L lake ecoregional total phosphorus standard.
17

Figure 13. Box plot summary of total nitrogen concentrations (mg/L) measured at each stream and lake station. The red line
denotes the 1.5 mg/L lake ecoregional total nitrogen standard.
18

Figure 14. Box plot summary of total organic carbon concentrations (mg/L) measured at each stream and lake station.
Conclusion
As with the 2019 Nutrient Study and the other associated studies, this project is part of a comprehensive
effort to resolve the relationship between physical and chemical conditions and ecological responses in
the Lower Catawba Basin. Certain ecological responses impair designated uses in the system and degrade
water quality as indicated by the cascade of regulatory 303(d) listings in the basin. This project builds on
studies conducted in previous years by DHEC and stakeholder partners and is bolstered by years of data
collected as part of DHEC’s ambient monitoring program. The aggregated results of these programs fill
important data gaps and provide a robust data set to develop, calibrate, and validate coupled watershed
and river/lake hydrodynamic and water quality models. The calibrated models will be used in setting site-
specific numeric nutrient and chlorophyll-a standards that are protective of designated uses for Lower
Catawba Basin.
Acknowledgments
This project was made possible through support from DHEC Bureau of Water (BOW) TMDL group as well
as Quality Assurance programs from the DHEC BOW and Bureau of Environmental Health Services
(BEHS). The BEHS laboratory processed and analyzed water quality samples from June through the end
of the project. Total chlorophyll-a and cyanotoxin samples were processed and analyzed by the BOW
Aquatic Science Programs (ASP). Field sampling was conducted by personnel from the BOW TMDL and
ASP groups.
19

Appendix A – Vertical Profile Section Graphs

Julian Day: 100 is April 9, 2020, 150 is May 29, 2020, 200 is July 18, 2020, 250 is Sept 6, 2020, 300 is
October 26, 2020
LCR-04 – Fishing Creek Reservoir off Bear Creek arm

20

21

22

CW-231 – Upstream Lake Wateree Headwater, below Cedar Creek Dam
Missing 8/24/2020

23

24

25

LCR-02 – Lake Wateree upstream of Wateree Creek arm
Missing 8/24/2020

26

27

28

LCR-03 – Lake Wateree off Dutchmans Creek arm
Missing 8/24/2020

29

30

31

CW-208 – Lake Wateree at S-20-101 (Dutchman Creek arm)
Missing 8/24/2020
Dissolved oxygen, pH and temperature section plots included above in main body of report

32

CW-207B – Mid-channel Lake Wateree at end of S-20-291

33

34

35