NC0024911_Fact Sheet_20240315

Fact Sheet
NPDES Permit No. NCO024911
Permit Writer/Email Contact:Nick Coco,[e-mail]
Date: June 22,2023
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: Metropolitan Sewerage District Buncombe County(MSD)/French
Broad River Water Reclamation Facility(WRF)
Applicant Address: 2028 Riverside Dr.,Asheville,NC 28804
Facility Address: 2225 Riverside Dr.,Woodfin,NC 28804
Permitted Flow: 40.0 MGD
Facility Type/Waste: MAJOR Municipal; 97.8%domestic, 2.2%industrial*
Facility Class: Grade IV Biological Water Pollution Control System
Treatment Units: Two multi-rake mechanical bar screens, Two vortex grit basins, Three
influent pumps with capacity of 35 MGD each, Instrumental flow
measurement, Three perforated-plate mechanical fine screens, 1st,2nd,
and 3rd stage RBCs(152 total), Three intermediate pumps, Four
intermediate clarifier cells (total volume 2 MG), Effluent chlorination
(liquid sodium hypochlorite),Effluent de-chlorination(liquid sodium
bi-sulfate)), Two gravity sludge thickeners -100 ft diameter each, Two
2.1 MG surge tanks, Three surge pumps with capacity of 5 MGD each,
Two 2.5-meter belt filter presses (gravity and pressure sections),
Fluidized bed incinerator(40 DT/day rated), One 2 MW back-up
generator(diesel), Two 1 MW back-up generators(diesel), 192 cloth-
media filter disks(10 micron), Two 450 KW gas generators,Three 850
KW hydro turbines (French Broad River source), 17-acre ash storage
lagoon, SCADA
Pretreatment Program(Y/N) Y; LTMP
County: Buncombe
Region Asheville
*Based off of permitted flows.
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Briefly describe the proposed permitting action and facility background: MSD Buncombe County has
applied for an NPDES permit renewal at 40.0 MGD for the French Broad River WRF. This facility serves
a population of approximately 173,000 residents, as well as 23 significant industrial users(SIUs),
including 14 categorical industrial users(CIUs),via a Division-approved pretreatment program. Treated
domestic and industrial wastewater is discharged into the French Broad River, a class B waterbody in the
French Broad River Basin. Outfall 001 is approximately 10 miles upstream of the NC/TN border.
In their application, MSD indicated an average daily volume of I&I of approximately 6 MGD. MSD has
continuous rehabilitation projects of replacing damaged piping/connections as identified by sewer camera
identification, cleaning approximately 50,000 liner feet of line/year and a commitment of$15million/year
on collection system projects.
MSD maintains a 17-acre sludge lagoon. At one point this lagoon was used to store ash(from an onsite
incinerator),grit, line cleanouts, grease, and site stormwater. The outfall from the lagoon returns to the
head of the plant.A septage receiving station has been built for the vacuum truck debris, site management
procedures were implemented in Fall 2003. Therefore grease,grit, and line cleanouts are no longer stored
in the lagoon. The permit contains Special Condition A.(8.)Ash Storage Lagoon, allowing the use of the
lagoon for ash storage.
Sludge disposal: Residuals are thickened and dewatered then incinerated.
2. Receiving Waterbody Information:
Receiving Waterbody Information
Outfalls/Receiving Stream(s): Outfall 001 —French Broad River
Stream Segment: 6-(54.75)
Stream Classification: B
Drainage Area(mi2): 966
Summer 7Q10(cfs) 466
Winter 7Q10(cfs): 595
30Q2 (cfs): 882
Average Flow(cfs): 2140
IWC (%effluent): 12
2022 303(d) listed/parameter: Not listed*
Subject to TMDL/parameter: Yes- State wide Mercury TMDL implementation.
Basin/HUC: French Broad River/06010105
USGS Topo Quad: ERNE
*While the portion of the French Broad River to which the French Broad River WRF discharges is not
considered impaired,the stream segment 6 miles downstream of the discharge [6-(54.75)e] is considered
impaired for Benthos in the 2022 303(d) list.
3. Effluent Data Summary
Effluent data for Outfall 001 is summarized below for the period of January 2019 through June 2023.
Table 1. Effluent Data Summary Outfal1001
Parameter Units Average Max Min
Permit
Limit
Flow MGD 23.1 67.54 14.5 MA 40.0
CBOD mg/1 14.4 87.2 < 2 WA 40.0
MA 25.0
Page 2 of 15

NH3N mg/1 19.7 49.8 6 Monitor&
Report
TSS mg/1 13.2 142 3.7 WA 45.0
MA 30.0
0>pH<
pH SU 7.3 7.77 6.16 6. 9.0
(geometric)
Fecal coliform #/100 ml 2.(ge 2 an) 2420 < 1 WA 400
MA 200
DO mg/1 7.8 9.9 5.8 DA>5.0
DM 28.0
TRC µg/1 20.1 28 20 (<50
compliance)
Conductivity µmhos/cm 502 755 7.38 Monitor&
Report
Temperature ° C 18 24.2 4.4 Monitor&
Report
NO2+NO3 mg/1 1.8 4.5 0.51 Monitor&
Report
TKN mg/1 25.4 58.4 12.5 Monitor&
Report
TN mg/1 27.2 59.3 13.4 Monitor&
Report
TP mg/1 3.1 5.7 0.98 Monitor&
Report
Total Hardness mg/1 53.6 418 34.4 Monitor&
Report
MA-Monthly Average,WA-Weekly Average,DM-Daily Maximum,DA=Daily Average
4. Instream Data Summary
Instream monitoring may be required in certain situations, for example: 1)to verify model predictions
when model results for instream DO are within 1 mg/1 of instream standard at full permitted flow; 2)to
verify model predictions for outfall diffuser; 3)to provide data for future TMDL;4)based on other
instream concerns. Instream monitoring may be conducted by the Permittee, and there are also
Monitoring Coalitions established in several basins that conduct instream sampling for the Permittee(in
which case instream monitoring is waived in the permit as long as coalition membership is maintained).
If applicable, summarize any instream data and what instream monitoring will be proposed for this
permit action: The current permit requires instream monitoring for dissolved oxygen,temperature,and
conductivity in accordance with 15A NCAC 02B .0508. Instream sampling is conducted upstream at dam
discharge to fish ladder adjacent to intake flume to the hydroelectric plant(location is approximately 2700
feet upstream of the hydroelectric plant,-0.5 miles upstream of the discharge)and downstream at Ledges
Park(approximately 4 miles downstream). Upstream and downstream dissolved oxygen samples are
collected three times per week during June, July,August and September then once per week in the
remaining months of the year.Upstream and downstream temperature and conductivity samples are
collected daily. In addition to DO,temperature and conductivity, quarterly monitoring for hardness
upstream of the facility is conducted. MSD Buncombe County also provided instream sampling data for
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fecal coliform in their electronic DMRs. Instream data from January 2019 through May 2023 has been
summarized below in Table 2.
Table 2. Instream Monitoring Data Summary
Upstream Downstream
Parameter Units
Average Max Min Average Max Min
Temperature ° C 15.3 28.7 1.4 15.4 25.6 0.9
DO mg/1 9.1 21.7 5.56 9.4 61.3 1.26
Conductivity µmhos/cm 44.3 119.4 26 51.3 135.4 9
Fecal Coliform #/100 ml (geomean) 60000 5 (geomean) 60000 5
188 154
Hardness mg/1 11.8 25 9.54 1 - I - I -
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 not greater than upstream temperature by more than 2.8 degrees Celsius [per 15A NCAC 02B .0211
(18)] during the period reviewed. It was concluded that no statistically significant difference exists
between upstream and downstream temperature.
Dissolved oxygen is a parameter of concern for aquatic life. Average downstream DO was above 5 mg/L
[per 15A NCAC 02B .0211 (6)] during the period reviewed. Downstream DO was observed at levels less
than 4.0 mg/L on one occasion during the period reviewed. Concurrent effluent concentrations oxygen-
consuming wastes(BOD5 and ammonia)were not observed at elevated levels, and it does not appear that
the effluent influenced the individual low downstream DO instance. It was concluded that no statistically
significant difference exists between upstream and downstream DO.
As the facility receives influent flow from several industrial users via an approved pretreatment program,
instream conductivity is tracked. It was concluded that a statistically significant difference exists between
upstream and downstream conductivity.
Fecal Coliform is a parameter of concern for aquatic life and human health. Instream monitoring for fecal
coliform was removed from the permit in 2018 based on the receiving stream not having been impaired
for fecal coliform. However,MSD conducted sampling and provided the Division with ambient fecal
coliform data. Based on this data review, it was concluded that no statistically significant difference exists
between upstream and downstream fecal coliform. Downstream fecal coliform was observed at levels
greater than 400/100mL in 25%of samples reported, and upstream fecal coliform was observed at levels
greater than 400/100mL in 28%of samples reported. While ambient fecal coliform was observed at
elevated levels during the period reviewed, concurrent effluent fecal coliform concentrations were
consistently lower than the instream. However,the French Broad River WRF discharges to class B
waters, and in accordance with the 2002 Instream Conductivity and Fecal Coliform Monitoring Guidance,
instream fecal coliform monitoring may only be removed from municipal or domestic wastewater permits
that do not discharge to waterbodies impaired due to fecal coliform or Class B waterbodies. As such,
instream monitoring for fecal coliform has been added back into the permit.
For verification of site-specific ammonia calculations,upstream ammonia and pH sampling has been
added to the permit. To track facility impact on ambient ammonia levels in the French Broad River while
MSD implements corrective actions to achieve compliance with future ammonia effluent limits,
downstream ammonia sampling has been added to the permit. For consistency amongst parameters, all
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upstream and downstream samples shall be collected three times per week during June,July,August and
September then once per week in the remaining months of the year.
Is this facility a member of a Monitoring Coalition with waived instream monitoring(YIN):NO
Name of Monitoring Coalition: N/A
5. Compliance Summary
Summarize the compliance record with permit effluent limits (past 5 years): The facility reported one
Total Residual Chlorine limit violation in 2018 and one CBOD limit violation in 2021 resulting in
enforcement.
Summarize the compliance record with aquatic toxicity test limits and any second species test results
(past 5 years): The facility passed 17 of 17 quarterly chronic toxicity tests, as well as all 4 second species
chronic toxicity tests from February 2019 to February 2023.
Summarize the results from the most recent compliance inspection: The last facility inspection conducted
in February 2023 reported that the facility was compliant.
6. Water Quality-Based Effluent Limitations (WQBELs)
Dilution and MixingZ ones
In accordance with 15A NCAC 213.0206,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/1 for Municipals)may be appropriate if deemed more stringent based on dilution and
model results.
If permit limits are more stringent than TBELs, describe how limits were developed: In lieu of BOD the
permit has secondary treatment standard limits for CBOD of 25 mg/1 as per 40 CFR 133.102.No changes
are proposed.
Ammonia and Total Residual Chlorine Limitations
Limitations for ammonia are based on protection of aquatic life utilizing an ammonia chronic criterion of
1.0 mg/1(summer) and 1.8 mg/1(winter). Acute ammonia limits are derived from chronic criteria,
utilizing a multiplication factor of 3 for Municipals and a multiplication factor of 5 for Non-Municipals.
Limitations for Total Residual Chlorine(TRC) are based on the NC water quality standard for protection
of aquatic life(17 ug/1) and capped at 28 ug/1(acute impacts). Due to analytical issues, all TRC values
reported below 50 ug/1 are considered compliant with their permit limit.
Describe any proposed changes to ammonia and/or TRC limits for this permit renewal: TRC limits have
been reviewed in the attached WLA and have been found to be protective.No changes are proposed.
Page 5 of 15

During the 2011 permit renewal, an Ammonia Reduction Evaluation condition was included for
evaluation of the feasibility and cost for the following ammonia reduction scenarios:
optimizing ammonia removal at the current plant via operational improvements; and
(22,)upgrading the plant to meet summer ammonia limits of 6.9 mg/L(Monthly Average) and 20.7 mg/L
(Weekly Average),and winter limits of 17 mg/L(Monthly Average) and 35 mg/L(Weekly Average).
Summer is defined as April 1 through October 31.
MSD submitted the evaluation on April 8, 2015. In their evaluation, MSD found that their current
treatment process,Rotating Biological Contactors(RBC), does not provide NH3-N removal, and an
Ammonia Reduction Evaluation was completed in 2016 as required by the 2011 permit renewal. The
evaluation report indicated that a compliance schedule of at least 12 years would be needed for the facility
to upgrade the plant and optimize NH3-N removal to meet proposed limits. The current permit includes a
12-year schedule of compliance for ammonia limits which is set to end October 1,2030. The limits being
incorporated at the end of the schedule of compliance are summer monthly average and weekly average
limits of 14.0 mg/L and 35.0 mg/L,respectively, and winter monthly average and weekly average limits
of 31.7 mg/L and 35.0 mg/L,respectively. These limits are based on calculations performed using site-
specific data available during the 2018 renewal process.
The existing site-specific ammonia limits,to take effect after the conclusion of the schedule of
compliance,have been reviewed in accordance with EPA's guidance"Aquatic Lift Ambient Water Quality
Criteria For Ammonia—Freshwater 2013". This review incorporated facility effluent temperature and
pH data from 9/2018 to 2/2023,DMR upstream temperature data from 9/2018 to 2/2023, and upstream
ammonia and pH data from AMS station E4280000 from 1/2015 to 2/2020 (most recent data available).
For calculation of site-specific ammonia limits,the 901h percentile of summer and winter upstream and
effluent pH and temperature and upstream ammonia is used. These values have been summarized in Table
3, shown below.
Table 3. Site-Specific Data Summary
Summer Winter Ammonia
pH Temp pH Temp Summer Winter
Effluent 90th 7.47 23.3 7.47 17.8 - -
Upstream 7.60 23.2 7.35 11.9 0.05 0.19
90th
Based on site-specific calculations, summer ammonia monthly average and weekly average limits have
been revised to 8.5 mg/L and 21.4 mg/L,respectively. Per 15A NCAC 02B .0404(c), "The winter
oxygen-consuming wasteload allocation shall not exceed two times the summer oxygen-consuming
wasteload limitations nor shall it be less restrictive than minimum treatment requirements."As such,
winter ammonia monthly average and weekly average limits have been revised to 17.0 mg/L and 35.0
mg/L,respectively.
In their renewal application,MSD requested extension of the ammonia schedule of compliance deadline
to October 1,2035. The Permittee informed the Division of a number of issues that have arisen during
their corrective action process including:
• In November 2020, a major fire in an MSD storage facility destroyed new equipment for the
High-Rate Primary Treatment(HRPT)project,leading to a 9-month delay related to re-
procurement of the parts,
• The Covid-19 global pandemic caused significant delays to the construction process by
interrupting equipment and material supply chains and staffing levels available at the job site,
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• The HRPT is not fully commissioned,preventing MSD from gathering performance data to
inform design,
• Anticipated capital costs are high and volatile,with supply chains issues skewing costs upward.
The Permittee conducted a Microsoft Teams call with NPDES Permitting staff and Asheville Regional
Office staff on March 17,2023 to discuss the state of their corrective action plan and to discuss the need
of extension to the deadline for the schedule of compliance. During this call,the Division discussed the
revisions to the ammonia limitations and requested that MSD provide an Ammonia Treatment Evaluation
Study,which would identify the plant's current capabilities as well as MSD's approach to plant upgrades
to achieve better ammonia treatment. This evaluation should provide a distinct timeline with general
actions to be taken by MSD to aid the Division in understanding the timeline needed for the French Broad
River WRF to most expeditiously achieve compliance with ammonia limitations.
MSD provided a package to the Division on June 26,2023 which included a narrative description of
troubles experienced at the facility related to their ammonia corrective actions and justification for a 5-
year extension to their ammonia schedule of compliance,their 2015 Ammonia Reduction Evaluation and
their April 2023 Scope of Services with Hazen and Sawyer, for a biological treatment alternatives
evaluation. The Scope of Services indicates a timeline that delivers a final evaluation report by September
2024. In their narrative,MSD explains that HRPT construction was completed in January 2023 but
inconsistent and inefficient operation of the HRPT system has delayed the 2-year performance testing as
required by the existing ammonia schedule of compliance. Additionally,MSD noted that the reduction of
the targeted limits,though more reflective of the outcome of their 2015 Ammonia Reduction Evaluation,
will require additional capital investment for the initial upgrade, and greater O&M costs to run the
system. MSD is of the opinion that this significant change in final effluent quality alone warrants a 5-year
extension to the compliance schedule. Another reason for requesting an extension to the permit schedule
is the sheer complexity of the biological upgrade. MSD's WRF is extremely limited in available space
and will make construction of the new biological treatment process difficult. The upgrade will be
constructed within the confines of the existing plant footprint, so phasing and temporary bypassing will
be required. Maintenance of Plant Operations (MOPO) and effluent compliance during construction will
perhaps be the most challenging aspect of the upgrade.
After further discussion between the Division and MSD, it was determined a more in-depth
implementation plan was required prior,which would provide additional information into the ammonia
treatability strategy for MSD and identify a critical path for achieving compliance with the proposed site-
specific ammonia limits. Hazen and Sawyer prepared a Technical Memorandum: French Broad River
Water Reclamation Facility Implementation Plan on behalf of MSD and MSD submitted the memo to the
Division for review on October 16, 2023. Based on review of the memo's outline of site conditions,
treatment alternatives, and construction/implementation scheduling, and an additional Microsoft Teams
discussion with the Permittee on 11/29/2023,the Division has agreed to extend the ammonia compliance
schedule as follows. Along with the extended schedule,the permit limits have been revised to include
interim limits as milestones throughout the construction schedule at the facility.
The schedule has been adjusted to the following:
Deadline Milestone
December 31,2024 Submit annual progress report
Biological Treatment Alternatives Evaluation:Perform initial parts: (a)Preliminary
evaluations; b Process alternatives development; c Process verification and selection
December 31,2025 Complete HRPT 2-year performance testing;Biological Treatment Alternatives
Evaluation: (a)preliminary evaluations;(b)process alternatives and development;(b)
process verification and selection updates
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December 31,2026 Biological Treatment Alternatives Evaluation: (a)Selected alternative concept
development; b Complete PER and submit to NC DE
December 31,2027 Biological Treatment Upgrade Project design: (a)Engineer selection;(b)Onsite piloting
and performance verification
December 31,2028 Pretreatment: (a)identification of Significant Industrial Users(SIUs)sending ammonia to
facility; (b)monitoring of or modification of Industrial User Permits(IUPs)to ensure
sampling of ammonia at identified SIUs
December 31,2029 Biological Treatment Upgrade Project design: Complete including: (a)All permitting;(b)
ATC submittal and approval; c 100%design/Issued for construction
December 31,2030 Biological Treatment Upgrade Project construction: (a)Advertise and bid;(b)Contractor
selection and award; c Mobilization
December 31,2031 Construction in progress; Submit annual progress report
December 31,2032 Construction in progress; Submit annual progress report
December 31,2033 Biological Treatment Upgrade Project construction: (a)portion of construction completion
and either: (b)Achieve compliance with interim ammonia monthly average limit of 29.0
mg/L and weekly average limit of 35.0 mg/L or(c)Provide written justification for delay
ammonia reductions including assurance that the construction timeline has been expedited
to achieve compliance with monthly average and weekly average ammonia limits of 23.0
mg/L and 35.0 mg/L,respectively,by December 31,2024 at the expense of achieving
compliance with limits outlined in item b
December 31,2034 Construction in progress; Submit annual progress report-if item(c)was satisfied in 2023
milestones,achieve compliance with monthly average and weekly average ammonia limits
of 23.0 mg/L and 35.0 mg/L,respectively.
December 31,2035 Biological Treatment Upgrade Project construction: (a)additional construction completion;
(b)Achieve compliance with interim ammonia monthly average limit of 23.0 mg/L and
weekly average limit of 35.0 mg/L
December 31,2036 Construction in progress; Submit annual progress report
December 31,2037 Biological Treatment Upgrade Project construction: (a)All construction complete;(b)
Achieve compliance with final summer ammonia monthly average limit of 8.5 mg/L and
weekly average limit of 21.4 mg/L and winter ammonia monthly average limit of 17.0
mg/L and weekly average limit of 35.0 mg/L
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%2 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 2019
and March 2023. 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 Monitoriniz. 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
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• 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 Beryllium, Total Chromium,Total Copper,
Total Cyanide,Total Lead, Total Nickel, Total Selenium, Total Silver, Total Zinc
• 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: None
detected
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.
Toxicity Testing Limitations
Permit limits and monitoring requirements for Whole Effluent Toxicity(WET)have been established in
accordance with Division guidance(per WET Memo, 8/2/1999). Per WET guidance, all NPDES permits
issued to Major facilities or any facility discharging"complex"wastewater(contains anything other than
domestic waste)will contain appropriate WET limits and monitoring requirements,with several
exceptions. The State has received prior EPA approval to use an Alternative WET Test Procedure in
NPDES permits,using single concentration screening tests,with multiple dilution follow-up upon a test
failure.
Describe proposed toxicity test requirement: This is a Major POTW, and a chronic WET limit at 12%
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/1)will
receive an MMP requirement. Industrials are evaluated on a case-by-case basis, depending if mercury is a
pollutant of concern. Effluent limits may also be added if annual average effluent concentrations exceed
the WQBEL value (based on the NC WQS of 12 ng/1) and/or if any individual value exceeds a TBEL
value of 47 ng/l.
Table 4. Mercury Effluent Data Summary
2019 2020 2021 2022 2023
#of Samples 4 5 2 1 1
Annual Average Conc. n L 8.5 9.3 22.1 <0.2 28.2
Maximum Conc., n /L 12.5 10.2 26.1 <0.2 28.2
TBEL, n /L 47
W BEL, n /L 102.2
Page 9 of 15

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. However, since the facility is>2 MGD and reported quantifiable levels of mercury(> 1
ng/1),the mercury minimization plan(MMP)has been maintained.
Other TMDL/Nutrient Management Strategy Considerations
If applicable, describe any other TMDLs/Nutrient Management Strategies and their implementation
within this permit: NA
Other WQBEL Considerations
If applicable, describe any other parameters of concern evaluated for WQBELs: 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 via a Chemical Addendum to NPDES Application table. As an attachment to the permit
application,MSD provided sampling event data from 2020, 2021 and 2022 for PFAS and 1,4-dioxane.
These samples were taken at the influent fine screen and chlorine contact chamber. EPA Method 537
(Modified)was used for analysis of PFAS. MSD reported detections of various PFAS compounds at their
influent fine screen and chlorine contact chamber during three of the four sampling events. 1,4-dioxane
was not detected in any sampling event. Additionally,MSD provided a chemical addendum(attached)
showing their participation in an ongoing 2023 Swim Season E. Coli Study. Please see Monitoring
Requirements for more information.
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: The current permit includes a
schedule of compliance for effluent ammonia limits that concludes on October 1, 2030. Based on
discussions with MSD and review of their submitted supporting information, an option to submit an
Ammonia Treatment Evaluation Study to justify extension of the schedule of compliance 5 years to
October 1,2035 has been added. Should no acceptable study be submitted and approved,the October 31,
2030 deadline is maintained. Please see Ammonia and Total Residual Chlorine Limitations for more
information.
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
BODS/TSS for Monthly Average, and 45 mgll for BODS/TSS for Weekly Average). YES
If NO,provide a justification for alternative limitations (e.g., waste stabilization pond). NA
Are 85%removal requirements for BOD51TSS included in the permit? YES
If NO,provide a justification (e.g., waste stabilization pond). NA
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
Page 10 of 15

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,but schedule of
compliance for ammonia limits may be extended by 5 years to October 31,2035 if sufficient justification
is submitted to and approved by the Division via an Ammonia Treatment Evaluation Study.
If YES, confirm that antibacksliding provisions are not violated: Justification is to be determined via an
Ammonia Treatment Evaluation Study prepared by an NC Licensed Professional Engineer and approved
by the Division. The evaluation will consider the most expeditious approach to achieving compliance
with the ammonia limits and will provide an updated perspective on the timeline based on existing
setbacks (summarized above in Ammonia and Total Residual Chlorine Limitations) and facility need.
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.
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 discharge
point is approximately 10 miles upstream of the border between North Carolina and Tennessee. To ensure
PFAS contamination does not cross State lines, and as the French Broad River WRF has a pretreatment
program,monitoring of PFAS chemicals has been added to the permit. EPA finalized Method 1633 in
January 2024 but has not yet published the method in the Federal Register as a 40 CFR 136 method. As
the French Broad River WRF accepts influent wastewater from several industrial facilities that are
potential sources of PFAS via the approved pretreatment program, effluent PFAS monitoring has been
added to the permit at a quarterly frequency using the.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 or more recent Draft Method 1633 or the January 2024 Final Method 1633. Sampling using
the draft method or the January 2024 Final Method 1633 shall take effect the first full calendar quarter
following 6 months after the effective date of the permit to provide MSD time to select a laboratory,
develop a contract, and begin collecting samples. Effective 6 months after EPA has a wastewater method
in 40 CFR136 published in the Federal Register,MSD shall conduct effluent monitoring using the 40
CFR136 Method 1633.
In addition to monitoring at the wastewater management facility, MSD shall identify and monitor SIUs
suspected of discharging PFAS compounds within 6 months of the permit effective date. MSDshall
update their Industrial Waste Survey- (IWS)to identify indirect dischargers of PFAS contributing to
concentrations experienced at the French Broad WRF. 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, MSD shall begin sampling of indirect dischargers identified as potential PFAS
Page 11 of 15

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 Requirement and Pretreatment.
The EPA 2012 Recreational Water Quality Criteria for Bacterial Indicators of Fecal
Contamination recommends states set bacteriological water quality standards for primary recreation
freshwaters using either the Escherichia coli or Enterococcus pathogenic indicators.North Carolina's
current recreational surface water quality standards for Class B (primary recreation)waters use the fecal
coliform bacteria group pathogenic indicator. The Division sent a letter to MSD on March 8, 2023
requesting participation in a E. coli Study being conducted across the state. This study is being conducted
to evaluate the financial impacts of switching to an E. coli standard for all Class B freshwaters. The data
will inform the Regulatory Fiscal Note a required part of the rulemaking package. The study covers the
2023 Swim Season,April through August, and requires instream and effluent monitoring and reporting of
fecal coliform,E. coh,turbidity,temperature,DO, conductivity and pH. Additionally, instream sampling
events are to be accompanied by a concurrent precipitation recording. MSD has submitted data for April
and May,to date.
The current permit includes Special Condition A.(6.)Groundwater Requirements,which provides detailed
instruction regarding monitoring of 19 parameters and a suite of volatile organic compounds (VOCs)
from four existing groundwater monitoring wells: MW-5,MW-6R,MW-7 and MW-8R. The Permittee
was also required to install four new monitoring wells associated with the Ash Storage Lagoon and the
wastewater treatment system regulator boundary. Upon completion of the new monitoring wells, existing
monitoring wells, MW1,MW2,MW3,MW4 and two earlier background wells shall be abandoned in
accordance with 15A NCAC 02C .0113. In addition to the monitoring requirements and well
development,the Permittee was required to provide a site map with waste boundaries for the Ash Storage
Lagoon,the location of all property boundaries and the location of each existing and new monitoring
well.
In discussion with the Asheville Regional Office (ARO), it was determined that the four new monitoring
wells have been installed and a site map was provided. As the site map was received,the site mapping
language has been removed from Appendix A. To date,monitoring well MW-1 has been properly
abandoned,but MW-2,MW-3 and MW-4 have not. Language has been added to Appendix A outlining
the requirement for proper closure of MW-2, 3 and 4.
Additionally,the ARO recommended removal of arsenic and silver from the list of groundwater analytes
and addition of nickel and cobalt based on groundwater sampling efforts conducted by ARO. The analyte
list has been revised to reflect this recommendation.
Detailed groundwater monitoring requirements and sampling plan have been included in the attachment
to the permit(See Appendix A). The Permittee shall work directly with DWR Ashville Regional Office
on the sampling plan. If any change is made to the sampling plan,the Permittee shall submit the approved
plan to the Division's NPDES Municipal Permitting Unit.
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 15

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 40.0 MGD No change 15A NCAC 2B .0505
CBOD5 MA 25.0 mg/l No change TQBEL. Secondary treatment
WA 40.0 mg/l standards/40 CFR 133 / 15A
Monitor and report NCAC 2B .0406 -CBOD
Daily equivalent; Surface Water
Monitoring, 15A NCAC 2B. 0500
NH3-N Schedule of Schedule of Compliance with WQBEL. 2023 WLA—site-
Compliance with December 31, 2037 deadline specific ammonia; Permittee
October 1,2030 and interim limits; request for extension of
deadline; compliance schedule and
Final Limits: Ammonia Treatment Evaluation
Summer: Summer: Study; Surface Water Monitoring,
MA 14.0 mg/l MA 8.5 mg/l 15A NCAC 2B. 0500
WA 35.0 mg/l WA 21.4 mg/l
Winter: Winter:
MA 31.7 mg/l MA 17.0 mg/l
WA 35.0 mg/1 WA 35.0 mg/l
Monitor and report Monitor and report Daily
Dail
TSS MA 30 mg/l No change TBEL. Secondary treatment
WA 45 mg/l standards/40 CFR 133 / 15A
Monitor and report NCAC 2B .0406; Surface Water
Daily Monitoring, 15A NCAC 2B. 0500
Fecal coliform MA 200/100ml No change WQBEL. State WQ standard, 15A
WA 400/100ml NCAC 2B .0200; Surface Water
Monitor and report Monitoring, 15A NCAC 2B. 0500
Dail
Temperature Monitor and Report No change Surface Water Monitoring, 15A
Daily NCAC 2B. 0508
DO >5 mg/l No change WQBEL. State WQ standard, 15A
Monitor and Report NCAC 2B .0200; 15A NCAC 02B
Daily .0500
pH 6-9 SU No change WQBEL. State WQ standard, 15A
Monitor and Report NCAC 2B .0200; 15A NCAC 02B
Daily .0500
Conductivity Monitor and Report No change Surface Water Monitoring, 15A
Daily NCAC 213. 0500
Total Residual DM 28 ug/L No change WQBEL. 2023 WLA. Surface
Chlorine Monitor and Report Water Monitoring, 15A NCAC
Daily 2B. 0500
TKN No requirement Monitor and Report Quarterly For calculation of TN
NO2+NO3 No requirement Monitor and Report Quarterly For calculation of TN
Total Monitor and Report No change Surface Water Monitoring, 15A
Nitrogen Quarterly NCAC 2B. 0500
Total Monitor and Report No change Surface Water Monitoring, 15A
Phosphorus Quarterly NCAC 2B. 0500
Page 13 of 15

Total Quarterly monitoring No changes Hardness-dependent dissolved
Hardness Upstream and in metals water quality standards
Effluent approved in 2016
See Special Condition A.(10.) Evaluation of PFAS contribution:
PFAS No requirement PFAS Monitoring pretreatment facility; Discharge
Requirements and above NC/TN border
Pretreatment
Instream Monitor and report Add upstream pH, and Based on Instream Data Review;
Monitoring for DO 3/week upstream and downstream Class B receiving stream—fecal
during June,July, fecal coliform and ammonia; coliform; Site-specific effluent
August and All instream monitoring ammonia limitations—upstream
September then once (except hardness)to be pH and ammonia; 15A NCAC 02B
per week in the conducted 3/week during .0508—variable sampling
remaining months of June,July,August and frequencies
the year and September then once per
temperature and week in the remaining months
conductivity daily of the year
Toxicity Test Chronic limit, 12% No change WQBEL. No toxics in toxic
effluent amounts. 15A NCAC 2B.0200 and
15A NCAC 2B.0500
Effluent Three times per No change; conducted in 40 CFR 122
Pollutant Scan permit cycle 2025,2026,2027
Pretreatment Special Condition No change GWR sites as non-significant IUs
Monitoring A.(4.)Pretreatment —explains what a non-significant
Monitoring IU is
Groundwater Special Condition No change;Update Unit 15A NCAC 02L .0200; Agreement
Requirements A.(6.) Groundwater name between the Division and
Requirements Permittee to include groundwater
sampling plan as attachment to the
permit.
Ash Storage Special Condition No change G.S. 143-215.1(b)
Lagoon A.(7.)Ash Storage
Lagoon
Mercury MMP Special No change; MMP maintained WQBEL. Consistent with 2012
Minimization Condition Statewide Mercury TMDL
Plan(MMP) Implementation.
Electronic Electronic Reporting No change In accordance with EPA Electronic
Reporting Special Condition Reporting Rule 2015.
MGD—Million gallons per day,MA- Monthly Average,WA—Weekly Average,DM—Daily Max
13. Public Notice Schedule:
Permit to Public Notice: 01/28/2024
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(919) 707-3609 or via email at nick.cocogdeq.nc.gov.
Page 14 of 15

15. Fact Sheet Addendum (if applicable):
The draft permit was submitted to MSD Buncombe County,EPA Region IV,Tennessee DEC, and the
Division's Asheville Regional Office,Monitoring Coalition Coordinator,Aquatic Toxicology Branch,
and Operator Certification Program for review. The Asheville Regional Office provided a comment
requesting revision of the facility component list to remove the reference to two 450-KW gas generators,
which are no longer at the facility based on the most recent facility inspection. The component list has
been revised to reflect this removal.No comments were received from any other party.
Were there any changes made since the Draft Permit was public noticed(Yes/No): YES
If Yes, list changes and their basis below:
• Some of the wording was changed in Special Condition A.(10.)to reflect the recently finalized
EPA Method 1633. Please review each paragraph carefully.
• As the two 450 KW gas generators are no longer in use,they have been removed from the facility
components list.
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
• Monitoring Frequency Reduction Evaluation
• POC Review Form
• WET Testing and Self-Monitoring Summary
• Compliance Inspection Report
• Requested Additional Information
• Chemical Addendum
• Ammonia Implementation Plan
Page 15 of 15

* LocaliQ
Georgia/North Carolina PO Box 631697 Cincinnati, OH 45263-1697
South Carolina
GANNETT
Pulic Notice
PROOF OF PUBLICATION North Carolina Environmen-
tal Management Commis-
sion/NPDES Unit
Wren Thedford 1617 Mail Service Center
Wren Thedford Raleigh,NC 27699-1617
Notice of Intent to Issue a
Deq-Division Of Water Res NPDES Wastewater Permit
NCad
1617 MAIL SERVICE CENTER R ver 49WWTPrench The North
Raleigh NC 27699 Carolina Environmental
Management Commission
proposes to issue a NPDES
wastewater discharge permit
to the person(s) listed below.
STATE OF WISCONSIN, COUNTY OF BROWN Written comments regarding
the proposed permit will be
accepted until 30 days after
the dateBefore the undersigned, a Notary Public,duly notice.ublish The Director of is
commissioned, qualified and authorized by law to NC Division of Water
Resources (DWR) may hold
administer oaths, personally appeared said legal clerk, who, a public hearing should there
be a significant degree of
being first duly sworn, deposes and says: that he/she is the public interest. Please mail
comments and/or informa-
legal clerk of The Asheville Citizen-Times, engaged in tion requests to DWR at the
above address. Interested
publication of a newspaper known as The Asheville Citizen- persons may visit the DWR
at 512 N. Salisbury Street,
Times, published, issued and entered as first class mail in Raleigh, NC 27604 to review
the information on file. Addi-
the city of Asheville, in Buncombe County, State of North tional information on NPDES
Carolina;that he/she is authorized to make this affidavit permits and this notice may
be found on our website:
lic-
and sworn statement;that the notice or other legal httic:s-heanc.gs,or by
g notices-hearings,or by call-
advertisement, a true copy of which is attached here to, ing [phone].The Metro-
politan Sewerage District
was published in said newspaper in the issues dated: Buncombe County [2028
Riverside Drive, Asheville,
NC 288041 has requested
renewal of NPDES permit
01/28/2024 NCO024911 for its French
Broad River Water Reclama-
tion Facility, located in
Buncombe County. This
That said newspaper in which said notice, paper, document permitted facility discharges
treated municipal and indus-
or legal advertisement was published was, at the time of trial wastewater to the
French Broad River, a class
each and every publication, a newspaper meeting all the B water In the French Broad
requirements and qualifications of Section 1-597 of the River Basin. Currently
q q ammonia, fecal coliform,
General Statutes of North Carolina and was a qualified dissolved oxygen, pH and
q total residual chlorine are
newspaper within the meaning of Section 1-597 of the water disclity harge limiteaffecd. This future
General Statutes of North Carolina. allocations in this segment of
the French Broad River.
January 28,2024
9779450
Sworn to and subscribed before on 01/28/2024
Legal Clerk r
Notary,Sta 1,County a. r n
My commision expires
Publication Cost: $142.82
Order No: 9779450 #of Copies:
Customer No: 512930 1
PO#:
THIS IS NOT AN INVOICE!
Please do uo[use 1hisform.forpay,nent reinuta„ce. V I C KY F E LTY
Notary Public
ES
te of Wisconsin Page 1 of 1

Hazen Technical Memorandum
October 16, 2023
To: Metropolitan Sewerage District of Buncombe County
From: Hazen and Sawyer
French Broad River Water Reclamation Facility
Implementation Plan
1. Introduction
1.1 Purpose
Metropolitan Sewerage District of Buncombe County(MSD)retained Hazen and Sawyer(Hazen)to
develop an Implementation Plan for the French Broad River Water Reclamation Facility(FBRWRF)to
meet the proposed Ammonia Compliance Schedule following the prior correspondence with the North
Carolina Division of Environmental Quality(NC DEQ). The prior correspondence included MSD's
response letter MSD NPDES Permit Renewal Request(Permit NC0024911)issued on June 26,2023, and
a meeting with MSD,NC DEQ, and Hazen on August 10',2023. This Implementation Plan precedes the
upcoming Biological Treatment Alternatives Evaluation for the FBRWRF which will be developed by
Hazen in parallel with the high-rate primary treatment(HRPT) optimization and performance testing
being performed by MSD.
This memorandum presents an implementation schedule to accommodate one of the biological processes
under consideration,noting that the selected/chosen process will be identified and summarized in a
Preliminary Engineering Report(PER)to be submitted to NC DEQ by December 31,2026.
1.2 Existing Treatment Facilities
The FBRWRF serves communities in Buncombe County and northern Henderson County. The FBRWRF
was commissioned in 1967 as a 25 million gallons per day(mgd) activated solids plant with carbon
oxidation and total suspended solids(TSS)removal. In 1988,the facility was converted to a rotating
biological contactors (RBC)process with an expanded capacity for 40 mgd. The RBCs were retrofitted
into the primary clarifiers,activated solids aeration tanks, and the secondary clarifiers. Subsequent plant
upgrades have been performed as follows:
• 1990—Installation of intermediate clarifiers with intermediate pumps
• 2013—Installation of cloth disc filters
• 2019—Headworks improvements including screening, grit removal, and flow equalization
• 2023—High-rate primary treatment(HRPT)provided by an Actiflo process
MSD French Broad River Water Reclamation Facility Page 1 of 17
Implementation Plan

Hazen October 16,2023
The recent headworks improvements and HRPT projects provided an elevated hydraulic profile to enable
construction of deeper process basins and to eliminate intermediate pumping in the future biological
treatment upgrade project. The flow equalization component of the headworks improvements project
provided 4.2 million gallons (MG)of storage volume which serves to mitigate peak flows into the plant
that exceed 65 mgd which will reduce process volume required in the future biological treatment upgrade
project. Figure 1-1 displays the existing process flow diagram.
Coarse Fine Grit Secondary Disc Filter Disinfection
Screen Screen Removal Actifio^ RBC 1 RBC 2 RBC 3 Clarifiers
X�illkl Zak,
Figure 1-1: Existing Process Flow Diagram
The existing site facilities and processes are shown in Figure 1-2 on the following page. The figure
demonstrates that there is substantial underground infrastructure(piping, electrical, etc.)in and around the
existing facilities which will require detailed bypass piping to be installed by the contractor during
construction to maintain the existing plant in operation while constructing and commissioning new
process facilities.
MSD French Broad River Water Reclamation Facility Page 2 of 17
Implementation Plan

Hazen October 16,2023
EQUALIZATION
�1 STORAGE &
'\ PUMPING
,N,
Lr ?tee
DISK •' _ ` _ +_ -r-1_-- r __
FILTERS �•=' -1 '— - �'=�`w= �- � --- ---
- -
fir-------- -- H R PT
_ -- -------- � ` r=- _ (ACTIFLO) . I
_L— — — a pp, I HEAD ORKS
RBC 3 _ I� FAQ LITY
_ RBC 2 = --- ---
__ RBC 1 s _
i INFLUEN ,
DISINFECTION _�_ -- ' PUM
STA
—
SECONDARY
CLARIFIERS — -- — — - — _ ✓� r '� ,,
�
apt
--- ----- -------
-- ----- ------
Figure 1-2: Existing Site Facilities and Processes
MSD French Broad River Water Reclamation Facility Page 3 of 17
Implementation Plan

Hazen October 16,2023
1.3 Existing Site Conditions
The FBRWRF site is constrained on all sides and cannot easily be expanded without major rock removal.
Figure 1-3 depicts topography showing the substantial grade adjacent to the site with over 100-foot
elevation gain into the hillsides.
. .. ::
NC251
Figure 1-3: Topography of Existing FBRWRF Site
Figure 1-4 depicts a cross section of the FBRWRF site from the original construction drawings, demonstrating the
substantial elevation change into the adjacent hillside.
2060
_- 2040
--
_ _ LIOKy�W'
-- - A04"SIRANM BLGN£R AND 117rL!'r
WILDING
Figure 1-4: Representative Cross Section through the FBRWRF Site
MSD French Broad River Water Reclamation Facility Page 4 of 17
Implementation Plan

Hazen October 16,2023
Figure 1-5 on the following page displays an aerial of the FBRWRF site identifying various site
constraints including rock that encompasses the site on the north and east side,the ash lagoon and
embankment dam located on the east side,Riverside Drive(NC 251)and the French Broad River located
on the west side of site, and the Duke Energy electrical substation on the south side of the site.
1.4 Final Effluent Permit
MSD operates the FBRWRF under the National Pollutant Discharge Elimination System(NPDES)permit
NCO024911 (expired December 31,2022). The permit allows for final effluent discharge to the French
Broad River. Table 1-1 summarizes the expired final effluent permit which indicated a compliance
requirement summer ammonia concentration of 14 mg/L by 2030. A courtesy draft renewal permit was
provided and indicated a lower ammonia requirement of 8.5 mg/L by 2035. Table 1-2 summarizes the
courtesy draft final effluent limits.
Table 1-1: Final Effluent Permit-Expired December 31,2022
Monthly Weekly Minimum Maximum
Parameter Average Average
Flow, mgd 40 - - -
Five-day Carbonaceous Biochemical Oxygen 25 40 -- -
Demand (cBOD5), mg/L
Total Suspended Solids(TSS), mg/L 30 45 - -
Ammonia (NH3-N), mg/L 14 35 -- -
April -October
NH3-N, mg/L
November—March
31.7 35 -- -
Dissolved Oxygen (DO), mg/L -- -- 5.0 -
Total Residual Chlorine(TRC), pg/L -- -- -- 28
Fecal Coliform, Geometric Mean N/100 mL 200 400 -- -
pH -- -- 6.5 9.0
Table 1-2: Courtesy Draft Renewal Permit
Monthly Weekly Minimum Maximum
Parameter Average Average
Flow, mgd 40 -- - -
Five-day Carbonaceous Biochemical Oxygen 25 40 - -
Demand (cBOD5), mg/L
Total Suspended Solids(TSS), mg/L 30 45 - -
Ammonia (NH3-N), mg/L
8.5 21.4
April -October --
NH3-N, mg/L 17 35 -- -
November—March
Dissolved Oxygen (DO), mg/L -- -- 5.0 -
Total Residual Chlorine (TRC), pg/L -- -- - 28
Fecal Coliform, Geometric Mean N/100 mL 200 400 -pH -- -- 6.5 9.0
MSD French Broad River Water Reclamation Facility Page 5 of 17
Implementation Plan

Hazen October 16,2023
ASH LAGOON AND
a;• EMBANKMENT DAM
NORTH SITE ROCK SLOPE
EAST SITE ROCK SLOPE
AML
M
L�•'s• ,' _� _ , /�� �''. � a-- _ ,fit
' 1
INFLUENT SEWER AND
AUJACLN f HIVLfi AND ROAD "'*� ELECTRICAL INFRASTRUCTURE A
d=MdML
Figure 1-5: FBRWRF Aerial View
MSD French Broad River Water Reclamation Facility Page 6 of 17
Implementation Plan

Hazen October 16,2023
2. Alternatives Analysis
To meet the proposed limits, it will be necessary for MSD to make major upgrades to the existing
biological process due to the inability of the RBCs to reduce the effluent ammonia to a concentration less
than the proposed draft permit. Six intensification biological processes will be evaluated including
conventional and emerging processes. These processes will be evaluated to leverage and utilize the prior
upgrades at the facility. The following biological processes will be evaluated:
• Aerobic Granular Sludge(AGS)
• Biological Aerated Filter(BAF)
• Integrated Fixed-Film Activated Sludge(IFAS)
• Membrane Aerated Biofilm Reactor(MABR)
• Moving Bed Biofilm Reactor(MBBR)
• Densified Activated Sludge(DAS)
The processes will be evaluated based on the site-specific ammonia limits proposed by NC DEQ in
courtesy draft renewal permit NC0024911. The processes will be further evaluated to provide flexibility
for future effluent nutrient limits in the French Broad River, if determined to be required by NC DEQ.
The FBRWRF site constraints require that the Biological Treatment Upgrades project be implemented
within the existing site to the extent possible. This will require new facilities to be designed and
constructed in phases so that adequate existing facilities and equipment remain in operation during
construction to ensure existing effluent permit limits continue to be met through construction.
2.1 Aerobic Granular Sludge (AGS)
The AquaNereda®process is licensed in North America by Aqua-Aerobic. The process utilizes
proprietary operating strategies and equipment to cultivate and retain Aerobic Granular Sludge(AGS)
granules for the purpose of achieving biological nutrient removal in a sequencing batch reactor(SBR)
configuration. AquaNereda® SBRs operate with three main phases(Fill/Draw,React and Settle)per each
cycle, or batch of wastewater treated.AGS granules retained in the reactor provide differing layers of
microbiological activity,whereas the presence of oxygen and electron acceptors decreases towards the
center of each granule. Figure 2-1:Figure 2-1 provides a process flow diagram of the AquaNereda®
process.
Coarse Screen Fine Grit Nereda'
Screen Removal MOW AGS Dec Fitter Disinfectwn
S
Figure 2-1: Aerobic Granular Sludge Process Flow Diagram
MSD French Broad River Water Reclamation Facility Page 7 of 17
Implementation Plan

Hazen October 16,2023
2.2 Biological Aerated Filter (BAF)
The BAF process combines biological nutrient removal, clarification,and filtration in one biofilm system.
Wastewater flows upward through a submerged aerated media bed. The media increases surface area
allowing for microbiological activity for nitrification.A nozzle and screen system retains the media in the
process and a portion of the treated effluent is stored above the media in a tank to serve as backwash
water. The backwash counter-current flow removes stored solids from the process. Figure 2-2 provides a
process flow diagram of the BAF process.
come Fine Gm Actific- Intermediate Biological Disc Filter Disinfection
Screen Screen Removal pumping Aerated Filter
1
Backwash Backwash
pumping Stcr,,:-
Figure 2-2: Biological Aerated Filter Process Flow Diagram
2.3 Integrated Fixed-Film Activated Sludge (IFAS)
The IFAS process utilizes conventional plug flow activated solids and a biofilm process in one system.
The conventional process contains an aerated bulk liquid with mixed liquor nitrification.Media is added
to the bulk liquid to increase surface area allowing for an intensification of microbiological activity.
Screens retain the media within the aeration tanks while the treated effluent flows to secondary
clarification. Figure 2-3 provides a process flow diagram of the IFAS process.
Coarse Fine Gnt WAS Secondary Disc Filter Disinfection
Screen Screen Removal Achfo'"
Clarifiers
Diagram
Figure 2-3: Integrated Fixed-Film Activated Sludge Process Flow Dia
g 9 g 9
MSD French Broad River Water Reclamation Facility
Implementation Plan

Hazen October 16,2023
2.4 Membrane Aerated Biofilm Reactor (MABR)
The MABR combines a conventional plug flow activated solids and a biofilm process in one system. The
conventional process contains an unaerated bulk liquid with mixed liquor. Gas permeable membrane
cassettes are submerged in the unaerated bulk liquid. Process air flows through the membranes to form an
aerobic biofilm for nitrification. The unaerated bulk liquid provides conditions for denitrification. The
treated effluent flows to secondary clarification. Figure 2-4 provides a process flow diagram of the
MABR process.
Coarse Fine Grit Membrane Seconds Disinfection
Actiflo" Aerated Biofilm Secondary Disc Fitter
Screen Screen Removal Reactor Clarifiers
-♦
Figure 2-4: Membrane Aerated Biofilm Reactor Process Flow Diagram
2.5 Moving Bed Biofilm Reactor (MBBR)
The MBBR process utilizes submerged aerated media. The media increases surface area to allow
microbiological activity.An aeration grid on the bottom provides oxygen for nitrification and mixing of
the media to promote contact with the wastewater. Screens retain the media within the aeration tanks
while the treated effluent flows to secondary clarification. Figure 2-5 provides a process flow diagram of
the MBBR process.
Coame Fine Grit Actiflo" Secondary Disinfection
Screen Screen Removal Moving Bed Biofilm Disc Filter
Reactor Clarifiers
Figure 2-5: Moving Bed Biofilm Reactor Process Flow Diagram
2.6 Densified Activated Solids (DAS)
The DAS process utilizes conventional plug flow activated solids process,but with additional process
flexibility which results in improved secondary solids settling thereby allowing the process to be operated
at higher mixed liquor concentrations of 5,000 to 5,500 mg/L. Densification operation assumes mixed
liquor settling characteristics with a 30-minute sludge volume index(SVI3o)ranging from 50 to 70 mL/g,
whereas conventional operation, assuming well-settling mixed liquor,typically has a SV13o ranging from
80 to 120 mL/g.
MSD French Broad River Water Reclamation Facility Page 9 of 17
Implementation Plan

Hazen October 16,2023
Densification can be achieved through a combination of external selection of superior settling activated
solids through surface wasting,hydrocyclones, and/or screens and metabolic selection with multi-
compartment selectors. Metabolic selection can be achieved with the installation of the three-pass
anaerobic zones as discussed in the previous alternative. This alternative includes hydrocyclones to
provide physical selection. Figure 2-6 provides a process flow diagram of the DAS process.
Coarse Fine Gr:
Screen Screen Remova, ACfif10" Anae,❑bic Anoxic Aerobic Secondary Disc Filter Disinfection
Clarifiers
--♦
Figure 2-6: Densified Activated Solids Process Flow Diagram
3. Implementation Schedule
The six biological alternatives that will be evaluated are considered intensification processes given the
site constraints and the requirement that the new infrastructure be constructed within the existing basin
footprint to the extent possible. Many of the biological alternatives are emerging technologies;therefore,
the most conventional process DAS was selected as an example for the development of the
implementation schedule.
Figure 3-1 on the following page provides a summary implementation plan and schedule, detailed in the
following subsections.
3.1 HRPT Optimization Schedule
The HRPT process is currently undergoing optimization with the manufacturer,with optimization to be
completed by end-of-year(EOY)2023. Once the process is optimized,the HRPT process will undergo
two-year performance testing to be completed by EOY 2025. Performance testing will provide the
following information:
• Validate reliable treatment capacity prior to finalizing the PER to ensure that the biological processes
are sized appropriately by confirming predictable COD and TSS removal;
• Verify solids production from the HRPT process for selection and sizing of solids handling processes.
MSD French Broad River Water Reclamation Facility Page 10 of 17
Implementation Plan

Hazen October 16,2023
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Figure 3-1: Summary Implementation Plan and Schedule [Note: Construction phasing as described in Section 3.4]
MSD French Broad River Water Reclamation Facility Page 11 of 17
Implementation Plan

Hazen October 16,2023
3.2 Biological Treatment Alternatives Evaluation and PER Schedule
The Biological Treatment Alternatives Evaluation will begin in 2024 and will include the following
phases:
• Preliminary evaluations with process screening and constructability evaluations;
• Process alternatives development to compare biological processes and rank the processes based on
multiple factors including treatment reliability, overall footprint,energy use and operational cost
considerations, capital cost, and construction schedule and maintenance of plant operations during
construction;
• Process verification and selection to include site visits to comparable operating treatment plants with
similar biological processes to those being considered;
• Selected alternative concept development to provide preliminary design of the recommended process
within the existing plant site to confirm constructability and reliable treatment of wastewater through
construction;
• Final preliminary engineering report(PER)development and submittal to NC DEQ,to be completed
by EOY 2026.
3.3 Biological Treatment Upgrade Project Detailed Design
The Biological Treatment Upgrades Project design will be developed based on the completed PER. The
project design phase will include the following phases and steps:
• Develop and issue a request for qualifications(RFQ) for design services with interview period and
selection of design engineer;
• Perform process piloting of the selected process at the FBRWRF site with performance verification to
ensure the biological treatment basins are sized appropriately and that functional controls are
optimized to treat a blended influent flow, i.e.,raw influent blended with HRPT effluent;
• Design submittals at 30%, 60%, 90%milestones including detailed phasing plans to implement
project with existing facilities in service;
• Permitting(state,local)including submission of authorization to construct(ATC)to NC DEQ,with
appropriate review times,resubmittals, and approvals;
• Finalization of Issued For Construction drawings and specifications,to be completed by EOY 2029.
MSD French Broad River Water Reclamation Facility Page 12 of 17
Implementation Plan

Hazen October 16,2023
3.4 Biological Treatment Upgrade Project Construction
Construction will include advertisement for bids,contractor selection and award;notice to proceed
(NTP), and a minimum of three phases of construction to maintain treatment and effluent quality through
the project. The example DAS three-phase construction plan is described in the following subsections,
which is expected to be similar for the various process alternatives being evaluated. Constructing the
project in phases will result in gradually improved effluent ammonia concentration as new process
facilities are commissioned and blended with RBC effluent. Figure 3-2 demonstrates the anticipated
combined(blended)effluent ammonia concentration based on the portion of flow treated through the
existing RBCs and the remaining portion treated through a new advanced process. The figure
demonstrates that the new effluent ammonia limit of 8.5 mg/L will be met upon completion of the three-
phase project.
30
it
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20 S
'5
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10
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%fb mNew Tr
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Figure 3-2: Construction Combined Final Effluent Ammonia
Figure 3-3 shows the existing flow path through the RBCs at the plant,which will achieve an effluent
ammonia concentration of approximately 25 mg/L based on the plant rated capacity of 40 mgd.
EXISTING PORTION OF FLOW THROUGH EXISTING RBCs 100%
PLANT PORTION OF FLOW THROUGH NEW PROCESS:N/A
COMBINED EFFLUENT AMMONIA=25 mg9(APPROX)
� ll 111111I i 11 1 t
l I_ I11" ulIII1I1 I —� i
Figure 3-3: Existing FBRWRF Flow Path
MSD French Broad River Water Reclamation Facility Page 13 of 17
Implementation Plan

Hazen October 16,2023
The example phased construction plan for the DAS process is described as follows with resulting
estimated effluent ammonia concentration at the end of each phase.
• Biological Treatment Upgrades Construction-Phase 1 (to be completed by EOY 2033):
■ Advertisement for bids, contractor selection and award,and NTP;
■ Mobilization,major site clearing and grading,rock excavation,and other preliminary work;
■ Demolition of select RBCs,piping, electrical, etc.
■ Construction of new process basins on available site space and within available RBC volume;
■ Construction of new blower building and associated electrical and piping;
■ Installation of flow distribution facilities to operate both existing RBCs and new process basins;
■ Installation of major(gravity)piping to new process basins(through highly congested corridors);
■ Plant electrical upgrades to provide power to new facilities and equipment while maintaining
existing facilities and equipment in operation;
■ Startup and commisioning of new process basins with demonstration and performance
verification;
■ Figure 3-4 demonstrates Phase 1 construction of the example DAS process with an estimated
33% of plant flow treated through the new process and with a resulting blended effluent ammonia
concetration of approximately 17 m L based on the plant rated capacity of 40 mgd.
f_-1 PHASE 1 PORTION OF FLOW THROUGH EXISTING RBCs.67%
PORTION OF FLOW THROUGH NEW PROCESS.33%
COMBINED EFFLUENT AMMONIA=17 mgrl(APPROX)
111J-LLlI I l l l l i l � e
' �ii�r�nrlilln.►. '1 Tn -�� -_,' , ,. � . j. U I
Figure 3-4: FBRWRF Biological Process Upgrade-Phase 1 Construction
MSD French Broad River Water Reclamation Facility Page 14 of 17
Implementation Plan

Hazen October 16,2023
• Biological Treatment Upgrades Construction—Phase 2 (to be completed by EOY 2035):
■ Demolition of select RBCs,piping, electrical, etc.
■ Construction of new process basins within available RBC volume;
■ Installation of flow distribution facilities to operate both existing RBCs and new process basins;
■ Installation of major(gravity)piping to new process basins(through highly congested corridors);
■ Additional electrical work for new facilities;
■ Startup and commisioning of new process basins with demonstration and performance
verification;
■ Figure 3-5 demonstrates Phase 2 construction of the example DAS process with an estimated
67% of plant flow treated through the new process and with a resulting blended effluent ammonia
concetration of approximately 10 m L based on the plant rated capacity of 40 mgd(i.e. capacity
will be available to meet the expired final effluent permit summer ammonia concentration of 14
mg/L).
(---73 PHASE 1 PORTION OF FLOW THROUGH EXISTING RBCS:33%
PHASE 2 PORTION OF FLOW THROUGH NEW PROCESS.67%
COMBINED EFFLUENT AMMONIA=10 mgll(APPROX)
LaT
Figure 3-5: FBRWRF Biological Process Upgrade—Phase 2 Construction
MSD French Broad River Water Reclamation Facility Page 15 of 17
Implementation Plan

Hazen October 16,2023
• Biological Treatment Upgrades Construction—Phase 3 (to be completed by EOY 2037):
■ Demolition of select RBCs,piping, electrical, etc.
■ Construction of final process facilities and/or modifications to existing facilities to complete
process upgrades volume;
■ Installation of major(gravity)piping to new process basins(through highly congested corridors);
■ Additional electrical work for new facilities;
■ Startup and commisioning of new process basins with demonstration and performance
verification;
■ Figure 3-6 demonstrates Phase 3 construction of the example DAS process with 100%of plant
flow treated through the new process and with a resulting effluent ammonia concetration of less
than 5 m /g/L based on the plant rated capacity of 40 mgd (i.e. capacity will be available to meet
the new effluent ammonia limit of 8.5 mg/L).
PHASE 1 PORTION OF FLOW THROUGH EXISTING RBCs:NIA
PHASE 2 PORTION OF FLOW THROUGH NEW PROCESS;100%
COMBINED EFFLUENT AMMONIA=<5 mgA
� ;PHASE 3
_wwrwroia �
sa.l�. I 1IL[I1T I h
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--- _ _ ...... .....
Figure 3-6: FBRWRF Biological Process Upgrade—Phase 3 Construction
3.5 Performance Testing
Each phase of construction includes performance testing to verify the process is optimized and the target
effluent ammonia concentration is being met, as included in the overall schedule.
MSD French Broad River Water Reclamation Facility Page 16 of 17
Implementation Plan

Hazen October 16,2023
4. Ammonia Compliance Schedule Summary
Table 4-1 summarizes the annual milestones for the ammonia compliance schedule, noting the following:
• Construction of the phased project as will be required at the FBRWRF will extend beyond 2035 to an
estimated final completion date of EOY 2037 due to the significant complexity of this project.
• MSD's prior request to NC DEQ to extend the NPDES ammonia compliance schedule from the
current date of October 1, 2030 to December 31, 2035 should provide adequate time for the
FBRWRF to meet the expired final effluent permit summer ammonia concentration of 14 mg/L.
• We recommend that MSD request that NC DEQ further extend the NPDES ammonia compliance
schedule to December 31, 2037 to provide adequate time for the FBRWRF to meet the lower summer
ammonia requirement of 8.5 mg/L included in the courtesy draft renewal permit.
Table 4-1: Proposed Ammonia Compliance Schedule
Timeline Milestone
By December 31, 2023 Complete HRPT optimization and begin 2-year performance testing
By December 31, 2024 Submit annual progress report
Complete HRPT 2-year performance testing;
By December 31, 2025 Biological Treatment Alternatives Evaluation: Perform initial parts: (a)Preliminary
evaluations; (b)Process alternatives development; (c) Process verification and
selection
By December 31, 2026 Biological Treatment Alternatives Evaluation: (a)Selected alternative concept
development; (b)Complete PER and submit to NC DEQ
By December 31, 2027 Biological Treatment Upgrade Project design: (a)Engineer selection; (b)Onsite
piloting and performance verification
By December 31, 2028 Biological Treatment Upgrade Project design: Complete design through 60%
By December 31, 2029 Biological Treatment Upgrade Project design: Complete including: (a)All permitting;
b ATC submittal and approval; c 100% design/ Issued for construction
By December 31, 2030 Biological Treatment Upgrade Project construction: (a)Advertise and bid; (b)
Contractor selection and award; c Mobilization
By December 31, 2031 Phase 1 construction in progress; Submit annual progress report
By December 31, 2032 Phase 1 construction in progress; Submit annual progress report
By December 31, 2033 Biological Treatment Upgrade Project construction: (a)Phase 1 completion; (b)
Demonstrate blended effluent ammonia concentration of<17 mg/L
By December 31, 2034 Phase 2 construction in progress; Submit annual progress report
By December 31, 2035 Biological Treatment Upgrade Project construction: (a)Phase 2 completion; (b)
Demonstrate blended effluent ammonia concentration of<14 mg/L
By December 31, 2036 Phase 3 construction in progress; Submit annual progress report
By December 31, 2037 Biological Treatment Upgrade Project construction: (a)Phase 3 completion; (b)
Demonstrate blended effluent ammonia concentration of<8.5 mg/L
MSD French Broad River Water Reclamation Facility Page 17 of 17
Implementation Plan

QOQo�\,�PN SEWEgq��
Metropolitan Sewerage District
_¢ OF BUNCOMBE COUNTY, NORTH CAROLINA
Zco�BF �GPQO
��NNiY,NAPS
June 26, 2023
Nick Coco, P.E.
Engineer III
NPDES Municipal Permitting Unit
NC DEQ/ Division of Water Resources/Water Quality Permitting
1617 Mail Service Center
Raleigh, NC 27699-1617
Re: MSD NPDES Permit Renewal Request (Permit NCO024911)
Dear Mr. Coco,
This letter is in response to your April 19, 2023 email and is also a follow up to our March 17, 2023 phone call
regarding MSD's request for a 5-year extension to its NPDES Ammonia Compliance Schedule. The compliance
schedule requires construction of a new biological treatment system by December 31, 2029, and compliance with
effluent ammonia limits (as specified in Section A.(1) of the October 1, 2018 permit) by October 1, 2030. In
addition to these milestones, the schedule also requires major interim capital improvements to be completed with
annual progress reporting. However, due to significant constraints, events beyond our control and real
scheduling issues, we are requesting the 5-year extension.
To date, MSD has met all reporting requirements and has completed two of the required plant improvement
projects, Plant Headworks Improvements and High Rate Primary Treatment (HRPT), totaling $27.9M in capital
expenditures. The HRPT is complete; however, MSD experienced a number of setbacks that delayed
construction and performance testing beyond the dates specified in the Ammonia Compliance Schedule. In
November 2020, a fire at MSD's Water Reclamation Facility (WRF)destroyed a large storage building that
housed equipment dedicated to the HRPT project. Reprocurement of the equipment was lengthy due to supply
chain issues (as a result of the pandemic) and progress on site slowed significantly. The project also
experienced staffing shortages due to pandemic quarantine restrictions that delayed the project further.
HRPT construction was completed in January 2023; however, inconsistent and inefficient operation of the HRPT
system has delayed the 2-year performance testing as required by the Ammonia Compliance Schedule. The
HRPT is still being optimized by the system vendor. Until the process is stabilized and is treating reliably,
performance testing is not viable. HRPT effluent data will heavily influence design of the downstream biological
upgrade so it is imperative that sufficient testing be completed. Proceeding with biological design without fully
vetting influent quality will greatly jeopardize MSD's ability to select an appropriate treatment approach, place a
higher level of risk on ultimate compliance and, in truth, be a waste of public time and money.
As expressed in previous correspondence, MSD is at a critical juncture in the development of the biological
upgrades at its WRF. In accordance with the Ammonia Compliance Schedule, we have recently embarked on a
($600,000) Biological Treatment Alternatives Evaluation Preliminary Engineering Report(PER)to identify the
best technology to accomplish both near term and long-term effluent goals. Our intent is not just to meet the
ammonia limits stipulated in the permit, but to position the WRF to accomplish nutrient removal should it be
required in the future. The PER will provide a well-planned, phased approach to accomplish these tasks.
The scope of the PER is centered around effluent ammonia limits as defined in the 2018 permit. Your April 19,
2023 email suggests that these values may change in the upcoming permit renewal on account of recently
—Protecting Our Natural Resources-
2028 Riverside Drive, Asheville, North Carolina 28804 Telephone: [phone] FAX[phone] Website:www.msdbc.org

conducted site-specific ammonia calculations. A Summer monthly concentration of 8.5mg/L is listed, equating to
a reduction of nearly 40%from the previously targeted limit. This reduction will require additional capital
investment for the initial upgrade, and greater O&M costs to run the system. MSD is of the opinion that this
significant change in final effluent quality alone warrants a 5-year extension to the compliance schedule.
Another reason for requesting an extension to the permit schedule is the sheer complexity of the biological
upgrade. MSD's WRF is extremely limited in available space and will make construction of the new biological
treatment process difficult. The upgrade will be constructed within the confines of the existing plant footprint, so
phasing and temporary bypassing will be required. Maintenance of Plant Operations (MOPO)and effluent
compliance during construction will perhaps be the most challenging aspect of the upgrade. Having spoken with
various qualified consultants, all have agreed the Ammonia Compliance Schedule is extremely tight and perhaps
unattainable given the complexities of the project.
Ammonia and Biological Treatment Evaluations
The email received on April 19, 2023 requested an Ammonia Treatment Evaluation Study be submitted to aid
NCDEQ in understanding the timeline necessary to most expeditiously achieve compliance with the existing
treatment limitations. The evaluation was to identify the WRF's current capabilities as well as MSD's approach to
plant upgrades to achieve better ammonia treatment. The Ammonia Reduction Evaluation, completed in 2015 at
the request of NCDEQ still accurately addresses the WRF's nitrification capabilities and identifies steps and
general actions being taken towards better ammonia removal. The PER being produced now will serve as an
addendum to the Ammonia Reduction Evaluation and will provide clear direction on a specific technology, steps
to be taken, and construction timeline. The PER is scheduled for completion in late 2024; however, an extension
to the completion date is being proposed to better align with HRPT performance testing. Detailed discussion has
been provided below on the Ammonia Reduction Evaluation, Biological Treatment Evaluation PER, and
proposed timeline for achieving ammonia-nitrogen limits.
2015 Ammonia Reduction Evaluation
MSD completed an Ammonia Reduction Evaluation in 2015 to evaluate the feasibility and costs for reducing
ammonia-nitrogen by (1) optimizing the existing plant with operational improvements, and (2) upgrading the plant
to meet proposed summer and winter ammonia limits, as defined in the 2011 NPDES permit. The limits used for
the evaluation closely resemble those recently calculated (i.e. April 2023)for MSD's site-specific discharge. For
this reason, the document remains a valid tool in assessing the WRF's capabilities of meeting proposed
ammonia concentrations. A comparison of the proposed limits, including those in the 2018 permit are shown
below.
Summer Winter
Date (April 1—Oct. 31) (Nov. 1—March 31)
Monthly Avg. Weekly Avg. Monthly Avg. Weekly Avg.
2011 NPDES (Req'd for 6.9 mg/L 20.7 mg/L 17.0 mg/L 35.0 mg/L
Ammonia Reduction Eval.)
2018 NPDES 14.0 mg/L 3S.0 mg/L 31.7 mg/L 3S.0 mg/L
2023 (Proposed Site Specific) 8.5 mg/L 21.4 mg/L 1 24.7 mg/L 1 61.8 mg/L
The Ammonia Reduction Evaluation described various treatment challenges that impacted performance in the
RBC process and recommended initial upgrades critical to improving, to the degree possible, biological treatment
and addressing the nitrification potential in the RBC process. As reflected in the 2015 report, this approach
would not achieve final limits but would provide some additional improvement in effluent ammonia levels.
The evaluation's recommended initial improvements included replacing failed/idle RBC units, reducing grit and
solids accumulation in the RBCs, reducing organic loading to the RBCs, and managing wet weather flows into
the WRF. These recommendations were to help optimize the RBC system and provide an appropriate treatment
foundation for upgrading biological treatment. Each recommendation is described in further detail below.
—Protecting Our Natural Resources-
2028 Riverside Drive, Asheville, North Carolina 28804 Telephone: [phone] FAX[phone] Website:www.msdbc.org

• Out of Service RBCs
In 2014, thirty-eight (38)of the 152 RBC units were inoperable, removed, or had broken shafts and were
not turning. Without these units in service, the total RBC surface area available for biological treatment
was greatly reduced. MSD underwent an intensive search for replacement RBC units and by 2017 all
inoperable units had been replaced. Since that time, additional units have failed and currently 11 units
are inoperable.
• Grit/Solids Accumulation in RBCs
Poor grit removal and lack of primary clarification resulted in the collection of solids and grit throughout
downstream processes. Settled solids in the RBC basins reduce residence time in the biological process
and accumulated solids in the interstices of the RBC units increases operating weight and loads on the
shafts, leading to failure. Additionally, solids and grit increase organic loading to the biological process.
Because nitrification does not occur until most of the organic load has been oxidized, increased solids
and grit loading reduces the likelihood of nitrification occurring in the RBC process.
Two major projects were completed as a result of the evaluation that significantly reduced solids and grit
loading. The first was the Plant Headworks Improvements project, placed online in 2019. This project
included the replacement of existing 1/4" bar screens with '/2" bar screens, installation of new'/4"fine
screens, and new vortex grit removal system. The project has helped reduce solids and grit loading into
the biological process. Headworks performance testing was one of the initial phases of the Ammonia
Compliance Schedule and was completed in 2020.
The second major project was the installation of the HRPT, a chemically-enhanced, high-rate primary
clarification process. Operation of the HRPT facility remains sporadic due to loss of sand ballast during
operation; however, when the process is running, the facility removes >80% TSS and >60% particulate
BOD. Higher levels of treatment are possible with increased coagulant and polymer doses but the goal
of the HRPT is to balance TSS removal rates while maintaining sufficient primary effluent ortho-P and
CBOD to support downstream biological processes. As mentioned above, MSD continues to work with
the HRPT vendor to come up with a permanent operational strategy, one that replicates the successful
results achieved in the 2014 pilot study.
• Wet Weather Flows
Surge/flow equalization was recommended as a management strategy for trimming peak flows during
wet weather operations and reducing adverse treatment process impacts such as loss of RBC biofilm
and nitrifier washout. As part of the Plant Headworks Improvements, two (2) out-of-service anaerobic
sludge digester tanks were converted into flow equalization storage. The tanks have a combined volume
of 4.2 MG and are used to mitigate flows into the plant that exceed 65mgd, the design treatment capacity
of the RBCs and other downstream processes. The tanks have been used approximately 6 times since
2019 and have proven successful in managing wet weather peaks and stabilizing flow through the WRF.
The Ammonia Reduction Evaluation also included the assessment of feasible treatment alternatives capable of
meeting the ammonia reduction targets. The short-listed alternatives included Activated Sludge, Moving Bed
Biofilm Reactor(MBBR), Integrated Fixed Film Activated Sludge (IFAS), and Membrane Bioreactor(MBR).
These technologies and others will be evaluated further in the PER.
A copy of the 2015 Ammonia Reduction Evaluation is included with this letter.
2024 Biological Treatment Evaluation PER
The Biological Treatment Evaluation PER will provide prioritized recommendations for the large capital projects
related to biological treatment improvements. As required by the Ammonia Compliance Schedule, the PER will
include a selected technology, specific steps to be taken to achieve ammonia limits, and design and construction
timelines. Phasing recommendations will also be included, along with methods for maintaining plant operations
during construction, and cost estimates. MSD's selected consultant, Hazen & Sawyer will provide the following
services:
• Influent wastewater characterization, and future flow and load projections. HRPT performance data is
critical to this step.
—Protecting Our Natural Resources-
2028 Riverside Drive, Asheville, North Carolina 28804 Telephone: [phone] FAX[phone] Website:www.msdbc.org

• Condition assessment of existing plant structures, equipment, and electrical systems.
• Capacity evaluation for future expansion of biological treatment process.
• Technology assessment for future biological treatment processes, including: Densified Activated Sludge
(DAS), Aerobic Granular Sludge (AGS), Moving Bed Biofilm Reactor(MBBR), Biological Aerated Filter
(BAF), Membrane Aerated Biofilm Reactor(MABR), and Integrated Fixed-Film Activated Sludge (IFAS).
• Preliminary permitting for new biological treatment process.
A copy of Hazen & Sawyer's Scope of Services is included with this letter for your review. MSD's Board of
Director's issued approval to begin the PER on May 17, 2023.
Proposed Revisions to Ammonia Compliance Schedule
Timeline Milestone
Complete HRPT optimization and begin 2-year performance
By December 31, 2023 testing. Continue with Biological Treatment Alternatives
Evaluation.
By December 31, 2025 Complete HRPT 2-year performance testing. Continue with
Biological Treatment Alternatives Evaluation.
By December 31, 2026 Complete Biological Treatment Alternatives Evaluation including
chosen alternative.
By December 31, 2029 Complete Biological Treatment system design and submit
application for ATC.
By December 31, 2034 Complete Biological Treatment system construction and begin
performance testing.
By December 31, 2035 Achieve compliance with the ammonia limits in Section A. (1).
We understand and appreciate that it is critical that MSD move forward diligently and be provided with the
necessary time to do a complete job. The long-term viability and compliance of the upgraded facility depends on
having sufficient time to complete this comprehensive project. We would appreciate a letter agreeing to extend
the schedule to 2035 so that we can move forward in the most effective manner possible
Sincerely,
Thomas E. Hartye
MSD General Manager
Cc:
Gary Perlmutter, NCDEQ
Dan Boss, NCDEQ
Forrest Westall, McGill Assoc.
Hunter Carson, MSD
Bart Farmer, MSD
—Protecting Our Natural Resources-
2028 Riverside Drive, Asheville, North Carolina 28804 Telephone: [phone] FAX[phone] Website:www.msdbc.org

NPDES Chemical Addendum
NPDES No. - NCO024911
Facility Name- French Broad River Water Reclamation Facility
Outfall No. -001, French Broad River, subbasin 04-03002 [HUC: 0601105]
Pollutant CAS number Method Number Reason Pollutant Believed Estimated Concentration
(Required) (if Applicable) Present in Discharge (If Known)
TKN 7727-37-9 351.2 30.47 mg/I
E. Coli Ecolilert 26.78 mpn/100ml
Soluble BOD 5210B 6.51 mg/I
NOx 1 11104-93-1 1 353.2 1 1 1.59 ppm
Notes:
1. Concentrations shown above are averages
2. PFAS & 1-4 Dioxane are not sampled at the effluent

MSD NPDES PERMIT RENEWAL
REQUEST FOR EXTENSION
PERMIT NCO024911
PaeSeNreo TO NCDEQ
DIVISION OF WATER RESOURCES
JnNunRv 5, 2024

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•
Mg-
♦ • • ■ ■ • ■ • • -__- � tom+

AVAILABLE SPACE HAS ALWAYS BEEN AN ISSUE
L71 r�
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y
LATE 1960S - 25 MGD ACTIVATED SLUDGE LATE 1980s - EXPANSION TO 40 MGD IN SAME FOOTPRINT

2015 AMMONIA REDUCTION
. �.. FINAL
EVALUATION
• IDENTIFIED FEASIBILITY AND COSTS OF REDUCING AMMONIA
Summer (April 1 - Oct. 31) Winter (Nov. 1 - March 31)
Monthly • Weekly Avg. Monthly Avg. Weekly Avg.
. • 1 • 1 • 1 •
"THE EXISTING RBC
CONFIRMED THAT RBC TREATMENT CANNOT PREDICTABLY ACHIEVE LIMITS PROCESS WAS NOT
• DESIGNED FOR
• LIMITED OPERATIONAL PROCESS CONTROL (SRT, INFLUENT LOADING) NITRIFICATION, THEREFORE
THE DESIGN RBC SURFACE
• INCLUDED PRELIM IDENTIFICATION OF POTENTIAL BIOLOGICAL TREATMENT AREA IS BASED ON
ALTERNATIVES (MBBR, IFAS, MBR) ORGANICS REMOVAL AND
NOT NITRIFICATION"
• RECOMMENDED OPERATIONAL AND CAPITAL IMPROVEMENTS TO INTRODUCE
NITRIFICATION IN THE TREATMENT PROCESS FOR AMMONIA REDUCTION

REPLACE ' TOTAL - 152 RBC UNITS
THE OUT OF * INOPERABLE UNITS REDUCE AVAILABLE SURFACE AREA FOR
TREATMENT AND IMPROVED NITRIFICATION
SERVICE RBC • THIRTY-EIGHT 38 UNITS WERE REPLACED PRIOR TO 2017
UNITS
, s
y �
03/2•9/2016 _ 04/02720`l'6

I
{i REDUCE GRIT AND SOLIDS
LOADING TO RBCS
r
r
rr-
• SETTLED SOLIDS REDUCE RESIDENCE TIME FOR
BIOLOGICAL TREATMENT, ADD WEIGHT TO RBCS
SOLIDS LOADING REDUCES LIKELIHOOD OF
f
NITRIFICATION
TWO MAJOR PROJECTS RECOMMENDED:
°s _� : 'j�" • s PLANT HEADWORKS IMPROVEMENTS —REDUCTION
IN SOLIDS AND GRIT LOADING
HIGH-RATE PRIMARY TREATMENT — REMOVAL OF
SUSPENDED SOLIDS AND PARTICULATE BOD

IK
PLANT HEADWORKS '
- _
Q
• PLACED ONLINE IN FEB. 2019
• '/2" BAR SCREENS
• '/4" FINE SCREENS
• VORTEX GRIT REMOVAL o
o
1 M OJ C P R E T T o
• 0.8 COS -
• CAPTURES >2X GRIT/SOLIDS
Grit/Debris Removed
AS PREVIOUS SYSTEM • ,o
60 —•
• COMPLETED PER THE Alf" so ••' `•a
C3 #-i • r 40 • • 4•
AMMONIA COMPLIANCE - irk ► ' •
1 30 • •• �•—•.- ,—•
SCHEDULE AHEAD OF DEC. U 20 �.�':••• "-- •
31 , 2020 .
10
'b N% 1q Nq
Grit/Debris Removed (Avg. cubic feet per day)

WET WEATHER
MANAGEMENT
�i• ----
TRIM PEAK FLOWS DURING WET =-
r
WEATHER TO REDUCE LOSS OF
BIOFILM AND NITRIFIER WASHOUT
• CONVERTED EXISTING DIGESTERS
r_
INTO 4.2MG EQUALIZATION
STORAGE •„'
• COMPLETED PER
THE AMMONIA COMPLIANCE
SCHEDULE AHEAD OF DEC. 31 ,
2020

e e
HIGH- RATE PRIMARY
TREATMENT ( " HRPT' l ) t .
r-
J
• CHEMICALLY-ENHANCED PRIMARY
TREATMENT
• SITE NOT CONDUCIVE TO TRADITIONAL
CLARIFIERS DUE TO LIMITED FOOTPRINT
• CAPABLE OF REMOVING >80% TSS AND T �� POW �
>60% BOD
• CONSTRUCTION COMPLETED JAN. 2023 JW
• $1 7.1 M PROJECT COST , __ _ �- I`�' • -
• EXPERIENCING OPERATIONAL DIFFICULTIES;
OPTIMIZING SYSTEM /
• DID NOT MEET AMMONIA COMPLIANCE -
SCHEDULE OF DEC. 31 , 2021 -�.�

YEP ., THAT ' S OUR PLANT . . . . .
-T- i
low.
jA

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1 • • . . . • • • . . • • . . • • • • . . . . . . . . • • • . . . . . . . . . . . . . . . . . . .'.'.'.'.'.'.'.'.•.'.'.'.•.•.'.'.•.'.'.'.•.•.'.•.•.'.'.'.'.'.•.'. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
. . . . • . . . • . . • . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . • . . . . . . . • .
OW
• • . • • • . • • • • • • . • • • • • • . . . 000 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . •. . . . . . . . . . . . . . . . . . . . . . .
1 • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . • . . . . . . . • 1
1 • • • • • • • • • • . . . • • • • • • • • . • . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
. . . . • . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . • . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1 • . . . . • . . . . . . • • • • . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . , . . . . . . . . . • • • . . • • . • • • • • • • • • • • • • • • • • • • • • . . • . . • • . . . • 1
• • • •• • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • •• •.• . • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • . • • • . • • . . • • • •
• • • • ♦ ♦ • . • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • 1
• ••.'.•.•.••'••• • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • 1
• .a e • a o '♦'.•.•.•.•.•.••'•'•'•'.'.'•'i i i i i i i i i i i i i i i i i i i i i 0 0 0 *%%%% 0 0% 0 0 0 0 0 4
I _ -
PROJECT SETBACKS
1
I x
s
MATERIALS . EQUIPMENT
COMPLICATED BY THE IMPACTS OF COVID- 1 9
RE-PROCUREMENT WAS LENGTHY, AND FURTHER
STAFFING SHORTAGES TO CONTRACTORS
THROUGHOUT 2021 AND 2022 DUE TO
QUARANTINE RESTRICTIONS

WHERE WE ARE NOW
• OPTIMIZING HRPT
• FINDING THE HYDRAULIC "SWEET SPOT"
• OPTIMAL CHEM DOSAGES, MIXER SPEEDS
• NEED A THOROUGH UNDERSTANDING OF PROCESS CAPABILITY AND EFFLUENT CHARACTERISTICS
• PRELIMINARY ENGINEERING REPORTS (PER)
• HAZEN & SAWYER WORKING ON BIOLOGICAL PER AND SOLIDS HANDLING PER
• TECHNOLOGY ASSESSMENT AND SELECTION
• CONSTRUCTION SEQUENCING/PHASING, MOPO
• DESIGN AND CONSTRUCTION TIMELINES, COSTS

• o r
1 �
` JfAMMONIA IMPLEMENTATION
l �
_:.
TREATMENT
- - . .
JL
CONSIDERED
_ ,•� .:'
PHASING OF CONSTRUCTION AND,'
will CONSTRUCTION CHALLENGES
����. •
MAINTAINING
♦ COMPLIANCE
. ♦ THROUGH
1
EACH PHASE vi
• COMPLIANCE SCHEDULE
• AMMONIA REDUCTION PHASING PLAN
JIM
� _ �' •
J imp I,

EXISTING TREATMENT PROCESS FLOW DIAGRAM
Fine Grit 3econaary Disc Filter D+sinfection
Screen Removal Actiflo- RBC 1 RBC 2 RBC 3 Clarifiers
EQUALIZATION
�. STORAGE &
PUMPING
--� oPr:SA nW _
DISK MAINTCNld.CF aAlOWr,w 46 13
FILTERS � +IRPr cHE%trAL
rL
3Uq0INGwa;6
I] ■F
rHRPT --
fl i f t III .,I w r��
(ACTIFLO)
S"I
-- i 6`r,:. " HEADWORKS
n
_,mot- II i� f� I ¢ FACILITY
-- RBC 3� wU -��
�� RBC 2
RBC 1 - Lt-JU
o.
n
INFLUENT
DISINFECTION PUMP
` r
^'- � �.�= a•,r�=>:5UREPUMPSa +, - � � STATION
h API.,HI op,IE !—
C
!\ et1LVINCw it 1 �-
SEC6NDf.RT -
',_ CLARIF11 a e � ���nr•MENr Sr�t:wv:E �� � —- '��
— r c? _
\ 1 4I
`f` 1 �t Il�e s��t�l w t 1�,/ .l�l.�r _ 0'4'.'�' ♦/ i._ ... �

50
EXISTING TREATMENT
CHALLENGES
•
45
MEET FUTURE
COMPLIANCE
40
35 '
.ti
PREVIOUSLY
0 25 t i' •
MENTIONED
CO �,i•7' •• .tom, ., .. ,f •� „ , ••� • ,
PROVIDES NO NOTICEABLE .' �
•N IN AMMONIA
• EQUIPMENT RELIABILITY AND
MAINTENANCE
0
Jan-20 Jul-20 Jan-21 Jul-21 Jan-22 Jul-22 Jan-23 Jul-23 Jan-24
• PI Ammonia Conc FNE Ammonia Conc —PI 30-day Mov. Avg —FNE 30-day Mov.Avg.
Inf. vs. EfF. Ammonia Concentrations

PROPOSED COMPLIANCE LIMITS AND SCHEDULE
• 2018 PERMIT INCLUDED AMMONIA COMPLIANCE SCHEDULE
• AMMONIA COMPLIANCE BY OCT. 1 , 2030
• SUMMER AVERAGES: MONTHLY - 14.0MG/L, WEEKLY - 35.0MG/L
• WINTER AVERAGES: MONTHLY - 3 1.7MG/L, WEEKLY - 35.0MG/L
• INTERIM PROJECTS AND MILESTONES
• DRAFT 2024 PERMIT
• REVISED COMPLIANCE SCHEDULE BY OCT. 1 , 2035
• SUMMER AVERAGES: MONTHLY - 8.5MG/L, WEEKLY - 2 1.4MG/L
• WINTER AVERAGES: MONTHLY - 17.0MG/L, WEEKLY - 35.0MG/L
• REVISIONS REQUESTED TO SCHEDULE

TREATMENT ALTERNATIVES
• AEROBIC GRANULAR SLUDGE (AGS/AQUANEREDA ®) • MEMBRANE AERATED BIOFILM REACTOR (MABR)
Coarse Screen Fine Grit Actfic, Nereda Disinfection Coarse Fine Grit Acfiflo,� _ _
Secondary Disc Filter Disinfection
Screen Removal AGS Disc Filter led
Screen Screen Removal Reactor Clarifiers
• BIOLOGICAL AERATED FILTER (BAF) MOVING BED BIOFILM REACTOR (MBBR)
IntermediateCoarse Fine Grit Actflo"Screen Screen Removal Pumping Aerated Filter -
ter
- Disc Filter Disinfection
Reactor Clarifiers
���� � �� �►fir ��� ��� . °'�� o� ���� ��� ;;��/ `��. �� �i,;���
0 • DENSIFIED ACTIVATED SLUDGE (DAS)
Pumping Storag: Coarse Fine Grit
Screen Screen Removal Actiflo'" Anaerobic Anoxic Aerobic Secondary Disc Filter Disinfection
Clarifiers
• INTEGRATED FIXED—FILM ACTIVATED SLUDGE IFAS
Coarse Fine Grit IFAS Secondary Disc Filter Disinfection
Screen Screen Removal Actiflo, Clarifiers
ikkk --�-\ W40
cj� t (�.

CONSTRUCTABILITY CHALLENGES
_ 1
2030 90 60 1
SIGNIFICANT TOPOGRAPHICAL
N
CHALLENGES TO THE NORTH AND
z 205 2040 0 EAST CREATES LIMITATIONS
o ti
s ry O'
,0
{. 2030 2020 2000 2p10 BOUNDING THE SITE.
ass 19$° , ' �y FRENCH BROAD RIVER T O THE WEST
V O
1960 �• ELECTRICAL SUPPLY AND RIVERSIDE
1940 40- 1950 � `
DR TO THE SOUTH
..�N 'jj1tt11
t Ott BLUE GRANITE SUBGRADE UNDER ALL
•1111tti1l!_�__ ___- tttlt! f r
t �ttrtlf!!.'`. ytt111t STRUCTURES
a ,rk-' .•ttttt��ltlllt�t'
UNDERGROUND PIPING
Oz6t
oZer
'_ossr 1940'- 1930 Mr 19Q° y9`L
1920.-1920
i'g
.OE6I_-•r f

CONSTRUCTABILITY CHALLENGES
2030
�^•-• l lO�s 2040
2050 N
2010
2020 2000
20301.9 6 0so
sr
ll
!sl
1960
i3 y
940 Y9 1950 r I
. 111��111, ,�1t�� �,■y�1�111�1� ,
gfffff u��■1 kit
a 111
q I
9NO rear,+rr.
0 �
9y
. r _
- — - - �1 SW 1930 M r 1920
3. 1920
1920
0£6I - __ w�wo�u....1�
.:.���•Wam VAT U MrN\%mw--
.igrr.ur
aai, r i
i
Section A-A

ASH LAGOON AND
EAST SITE ROCK SLOPE
ao
t •
Wk
NORTH SITE ROCK SLOPE
Alp
A�t*,00 0— -
op
Xw-
INFLUENT SEWER AND
ION
117
• \ ;_
w
.- ,• �, -- _ _may- - _ _
� � � ' 'fir �~�'. .. _. _- , 4 • � rim
/ \ *
F
i •

AmmudMhww
F oo--op
•
----- ----- ---------- ----- --�ii drR• ��s

• • • • • • • • • • • •
PHASE 1 PORTION OF FLOW THROUGH EXISTING RBCs: 67%
PORTION OF FLOW THROUGH NEW PROCESS: 33%
I
BLOMR BUILDING o
I }
L!..ram__
CLARCERS T 33% 11. -
o
\ J _ 0
'- _ t R t R t ■ f R 0 ♦ f R I P ! R '

• • • • • • • • • • • •
PHASE 1 PORTION OF FLOW THROUGH EXISTING RBCS: 33%
PHASE 2 PORTION OF FLOW THROUGH NEW PROCESS: 67%
Bl0'NER BUILDING -_ � —
�.
i
1 R [ N c N B R O A D R I Y R R

• • • • • • • • • • • •
PHASE 1 PORTION OF FLOW THROUGH EXISTING RBCs: N/A
PHASE 2 PORTION OF FLOW THROUGH NEW PROCESS: 100%
0 PHASE 3
• 1. BLOWER BUILDING -
(�0 r1
j
j�7 111T - 100% - ❑ Ilf �1 -
, t 1 �
e0O Lull
oL
rT_r7 T rT_ - TI
r
TTT
-
i
R 2 R c 111 9 9 0 • D R 1 7 1 R

Timeline Comparison
Timeline Milestones as Proposed by MSD(2023-10-16) Milestone(As revised by the State) Milestone(As suggested by MSD in 2023-11-13 Email)
By December 31,2023 Complete HRPT optimization and begin 2-year performance testing Complete HRPT optimization and begin 2-year performance testing Complete HRPT optimization and begin 2-year performance testing
Submit annual progress report,Biological Treatment Alternatives Evaluation: Submit annual progress report;Biological Treatment Alternatives Evaluation:
Perform initial parts:(a)Preliminary evaluations;(b)Process alternatives Perform initial parts:(a)Preliminary evaluations;(b)Process alternatives
By December 31,2024 Submit annual progress report development;(c)Process verification and selection development;(c)Process verification and selection
Complete HRPT 2-year performance testing;Biological Treatment Alternatives Complete HRPT 2-year performance testing;Biological Treatment Alternatives
Evaluation:Perform initial parts:(a)Preliminary evaluations;(b)Process Biological Treatment Alternatives Evaluation:(a)Selected alternative concept Evaluation:(a)Selected alternative concept development;(b)Complete PER and
By December 31,2025 alternatives development;(c)Process verification and selection development;(b)Complete PER and submit to NC DEQ submit record copy to NC DEC.
Biological Treatment Alternatives Evaluation:(a)Selected alternative concept Biological Treatment Upgrade Project design:(a)Engineer selection;(b)Onsite Biological Treatment Upgrade Project design:(a)Engineer selection;(b)Onsite
By December 31,2026 development;(b)Complete PER and submit to NC DEQ piloting and performance verification piloting and performance verification
Biological Treatment Upgrade Project design:Complete including:(a)All
Biological Treatment Upgrade Project design:(a)Engineer selection;(b)Onsite permitting;(b)ATC submittal and approval;(c)100%design/Issued for
By December 31,2027 piloting and performance verification construction Biological Treatment Upgrade Project design:Complete design through 60%
Biological Treatment Upgrade Project design:Complete including:(a)All
Biological Treatment Upgrade Project construction:(a)Advertise and bid;(b) permitting;(b)ATC submittal and approval;(c)100%design/Issued for
By December 31,2028 Biological Treatment Upgrade Project design:Complete design through 60% Contractor selection and award;(c)Mobilization construction
Biological Treatment Upgrade Project design:Complete including:(a)All
permitting;(b)ATC submittal and approval;(c)100%design/Issued for Biological Treatment Upgrade Project construction:(a)Advertise and bid;(b)
By December 31,2029 construction Phase 1 construction in progress;Submit annual progress report Contractor selection and award;(c)Mobilization
Biological Treatment Upgrade Project construction:(a)Advertise and bid;(b)
By December 31,2030 Contractor selection and award;(c)Mobilization Phase 1 construction in progress;Submit annual progress report Phase 1 construction in progress;Submit annual progress report
Biological Treatment Upgrade Project construction:(a)Phase 1 completion;(b)
Achieve compliance with interim ammonia monthly average limit of 17.0 mg/L and
By December 31,2031 Phase 1 construction in progress;Submit annual progress report weekly average limit of 35.0 mg/L Phase 1 construction in progress;Submit annual progress report
Biological Treatment Upgrade Project construction:(a)Phase 1 completion;(b)
Demonstrate reduction in blended effluent ammonia concentration;submit annual
By December 31,2032 Phase 1 construction in progress;Submit annual progress report Phase 2 construction in progress;Submit annual progress report progress report
Biological Treatment Upgrade Project construction:(a)Phase 2 completion;(b)
Achieve compliance with interim summer ammonia monthly average limit of 10
Biological Treatment Upgrade Project construction:(a)Phase 1 completion;(b) mg/L and weekly average limit of 30 mg/L and winter ammonia monthly average
By December 31,2033 Demonstrate blended effluent ammonia concentration of<17 mg/L limit of 17.0 mg/L and weekly average limit of 35.0 mg/L Phase 2 construction in progress;Submit annual progress report
Biological Treatment Upgrade Project construction:(a)Phase 2 completion;(b)
Demonstrate reduction in blended effluent ammonia concentration;submit
By December 31,2034 Phase 2 construction in progress;Submit annual progress report Phase 3 construction in progress;Submit annual progress report annual progress report
Biological Treatment Upgrade Project construction:(a)Phase 3 completion;(b)
Achieve compliance with final summer ammonia monthly average limit of 8.5 mg/L
Biological Treatment Upgrade Project construction:(a)Phase 2 completion;(b) and weekly average limit of 21.4 mg/L and winter ammonia monthly average limit
By December 31,2035 Demonstrate blended effluent ammonia concentration of<14 mg/L of 17.0 mg/L and weekly average limit of 35.0 mg/L Phase 3 construction in progress;Submit annual progress report
Biological Treatment Upgrade Project construction:Substantial completion of
By December 31,2036 Phase 3 construction in progress;Submit annual progress report Project;(b)Begin Commissioning and Performance Testing
Biological Treatment Upgrade Project construction:(a)Phase 3 completion;(b) Meet blended effluent ammonia concentration of<8.5 mg/L,submit final project
By December 31,2037 Demonstrate blended effluent ammonia concentration of<8.5 mg/L report

Summarized Timeline Comparison
Timeline Milestones as Proposed by MSD(2023-10-16) Milestone(As revised by the State) Milestone(As suggested by MSD in Z023-11-13 Email)
By December 31,2023 Complete HRPT optimization and begin 2-year performance testing Complete HRPT optimization and begin 2-year performance testing Complete HRPT optimization and begin 2-year performance testing
By December 31,2024 Progress Report PER-Year 1 of 2 PER-Year 1 of 2
HRPT-2-yr performance Data Compelte HRPT-2-yr performance Data Compelte
By December 31,2025 PER-Year 1 of 2 PER-Year 2 of 2,Submit to NCDEQ PER-Year 2 of 2,Submit to NCDEQ
By December 31,2026 PER-Year 2 of 2,Submit to NCDEq Engineer Selection and Piloting Engineer Selection and Piloting
Complete 6096 Design;
Complete 100%Design;
ey December 31,2027 Engineer Selection and Piloting Complete Permitting including A7C Complete 6096 Design
Complete 300%Design;
By December 31,2028 Complete 6096 Design Advertise Project,Select Contractor and Start Construction Complete Permitting including ATC
Complete 100%Design;
By December 31,2029 Complete Permitting including A7C Phase 1 construction in progress;Submit annual progress report Advertise Project,Select Contractor and Start Construction
ey December 31,2030 Advertise Project,Select Contractor and Start Construction Phase 1 construction in progress;Submit annual progress report Phase 1 construction in progress;Submit annual progress report
By December 31,2031 Phase 1 construction in progress;Submit annual progress report Phase 1[omplete Phase 1 construction in progress;Submit annual progress report
SUMMARIZED PROPOSED COMPLIANCE SCHEDULE
By December 31,2032 Phase 1 construction in progress;Submit annual progress report Phase 2 construction in progress;Submit annual progress report Phase 1 Complete
ey December 31,2033 WNW Complete Phase 2 construction in progress;Submit annual progress report
Nor 31,2034 Phase 2 construction in progress;Submit annual progress report Phase 3 construction in progress;Submit annual progress report
ey December 31,2035 Completion of Construction and Meeting Effluent NH3-N limit Phase 3 construction in progress;Submit annual progress report
Biological Treatment Upgrade Project construction:Substantial completion of
By December 31,2036 Phase 3 construction in progress;Submit annual progress report Project;(b)Begin Commissioning and Performance Testing
Meet blended effluent ammonia concentration of c8.5 mg/L,submit final project
By December 31,2037 Completion of Construction and Meeting Effluent NH3-N limit report
PRELIMINARY PERIOD
PILOTING DESIGN PERIOD
PERIODCONSTRUCTION AND COMMISSIONING

. - - 1 1 1 • 35 8,000
Average 21.6 mg/L •
Max. 31.9 mg/L 30 7,000
Min. 6.5 mg/L • • •
• • 0 0 6,000
10'" Perc. 17.4 mg/L 25 '
19
90'" Perc. 26.4 mg/L V 5,000
20 .• • •
•.• • • • �• • A•A •• cC
• • - - 1 1 1 1 1 1 1 C • .' • • ` • 4,000
• • . cv
Average 18.9 mg/L 21 .9 mg/L 24.1 mg/L ° 3,000
c • ' •
Max. 23.9 mg/L 26.5 mg/L 31 .9 mg/L v 10 •
2,000
90'" Perc. 21 .5 mg/L 25.0 mg/L 28.7 mg/L
5 •
1,000
Maximum Month Flow Peak Day Flow
mgd mgd PF mgd PF 0 0
24.4 30.7 1.26 67.2 2.75 Jan-20 Jul-20 Jan-21 Jul-21 Jan-22 Jul-22 Jan-23 Jul-23 Jan-24
22.7 29.8 1.31 67.3 2.97
21.2 24.4 1.15 53.7 2.54
- ••- 22.8 28.3 1.24 62.7 2.75 PI Ammonia Conc. PI Ammonia Load -30-day Mov. Avg. -30-day Mov. Avg

PROPOSED INTERIM LIMITS
• DRAFT 2024 PERMIT
• REVISED COMPLIANCE SCHEDULE BY OCT. 1 , 2035
• SUMMER AVERAGES:
• MONTHLY - 8.5MG/L, WEEKLY - 21.4MG/L
• WINTER AVERAGES:
• MONTHLY - 17.0MG/L, WEEKLY - 35.0MG/L
• PROPOSED INTERIM COMPLIANCE LIMITS BY NCDEQ
• COMPLETION OF PHASE 1 - 33% OF NEW INFRASTRUCTURE INSTALLED
• SUMMER AND WINTER:
• MONTHLY - 17.0 MG/L, WEEKLY - 35.0 MG/L
• COMPLETION OF PHASE 2 - 66% OF NEW INFRASTRUCTURE INSTALLED
• SUMMER:
• MONTHLY - 10.0 MG/L, WEEKLY - 30.0 MG/L
• WINTER:
0 MONTHLY - 17.0 MG/L, WEEKLY - 35.0 MG/L

PROPOSED INTERIM LIMITS
BASELINE:
Projected Projected Proposed Interim
• INFLUENT CONC. MAX = 35 MG/L Summer Bien Winter Blende Monthly Compliance
• PROPOSED EFFLUENT LIMITS Phases ded Conc. d Conc. Limit *
• WINTER = 17.0 MG/L Phase • • • I • • 1 •
• SUMMER = 8.5 MG/L
• FLOW THROUGH NEW TECHNOLOGY
• PHASE 1 = 33% INFRASTRUCTURE
• PHASE 2 = 66% INFRASTRUCTURE
PROJECTED EFFLUENT CONCENTRATIONS *ALL WEEKLY INTERIM COMPLIANCE LIMITS ARE 35.0 MG/L

Freshwater RPA - 95% Probability/95% Confidence Using Metal Translators
MAXIMUM DATA POINTS = 58
REQUIRED DATA ENTRY
Table 1. Project Information Table 2. Parameters of Concern
❑ CHECK IF HQW OR ORW WQS Name WQs Type Chronic Modifier Acute PQL Units
Facility Name French Broad River WRF Par01 Arsenic Aquactic Life C 150 FW 340 ug/L
WWTP/WTP Class IV Par02 Arsenic Human Health C 10 HH/WS N/A ug/L
Water Supply
NPDES Permit NCO024911 Par03 Beryllium Aquatic Life NC 6.5 FW 65 ug/L
Outfall 001 Par04 Cadmium Aquatic Life NC 0.6457 FW 3.6682 ug/L
Flow, Qw (MGD) 40.000 Par05 Chlorides Aquatic Life NC 230 FW mg/L
Receiving Stream French Broad River Par06 Chlorinated Phenolic Compounds Water Supply NC 1 A ug/L
HUC Number 06010105 Par07 Total Phenolic Compounds Aquatic Life NC 300 A ug/L
Stream Class B Par08 Chromium III Aquatic Life NC 129.8369 FW 1016.9388 ug/L
❑ Apply WS Hardness WQC Par09 Chromium VI Aquatic Life NC 11 FW 16 pg/L
7Q10s (cfs) 466.000 Par10 Chromium, Total Aquatic Life NC N/A FW N/A pg/L
7Q10w (cfs) 595.00 Par11 Copper Aquatic Life NC 8.7278 FW 11.9743 ug/L
30Q2 (cfs) 882.00 Par12 Cyanide Aquatic Life NC 5 FW 22 10 ug/L
QA(cfs) 2140.00 Par13 Fluoride Aquatic Life NC 1,800 FW ug/L
1Q10s (cfs) 376.30 Par14 Lead Aquatic Life NC 3.3649 FW 88.5870 ug/L
Effluent Hardness 52.02 mg/L (Avg) Par15 Mercury Aquatic Life NC 12 FW 0.5 ng/L
------------- ----------------------
Upstream Hardness 25 mg/L (Avg) Par16 Molybdenum Human Health NC 2000 HH ug/L
-------------7 ----------------------
Combined Hardness Chronic 28.17 mg/L Par17 Nickel Aquatic Life NC 41.1919 FW 378.0860 pg/L
------------- ----------------------
Combined Hardness Acute 28.82 mg/L Par18 Nickel Water Supply NC 25.0000 WS N/A pg/L
----------------------
Data Source(s) Default Upstream Hardness of 25 mg/L used due to Parts Selenium Aquatic Life NC 5 FW 56 ug/L
❑ CHECK TO APPLY MODEL average upstream hardness from DMR review being Par20 Silver Aquatic Life NC 0.06 FW 0.3786 ug/L
< 25 mg/L.
Par21 Zinc Aquatic Life NC 140.2366 FW 141.8107 ug/L
Par22
Par23
Par24
24911 RPA, input
6/26/2023

REASONABLE POTENTIAL ANALYSIS
H1 H2 Use"PASTE SPECIAL Use"PASTE SPECIAL
Effluent Hardness Values"then"COPY" Upstream Hardness Values"then"COPY"
Maximum data .Maximum data
points=58 points=58
Date Data BDL=1/2DL Results Date Data BDL=1/2DL Results
1 8/6/2019 59.3 59.3 Std Dev. 49.4951 1 Default 25 25 Std Dev. N/A
2 8/7/2019 64.9 64.9 Mean 52.0224 2 Mean 25.0000
3 9/3/2019 58.6 58.6 C.V. 0.9514 3 C.V. 0.0000
4 10/7/2019 59.9 59.9 n 58 4 n 1
5 11/5/2019 70.3 70.3 10th Per value 37.70 mg/L 5 10th Per value 25.00 mg/L
6 11/7/2019 66.3 66.3 Average Value 52.02 mg/L 6 Average Value 25.00 mg/L
7 12/3/2019 53.7 53.7 Max. Value 418.00 mg/L 7 Max. Value 25.00 mg/L
8 1/9/2020 54.7 54.7 8
9 2/3/2020 37.6 37.6 9
10 2/18/2020 43.6 43.6 10
11 3/9/2020 40.6 40.6 11
12 4/13/2020 58.8 58.8 12
13 5/4/2020 43.5 43.5 13
14 5/14/2020 38.2 38.2 14
15 6/1/2020 42.6 42.6 15
16 7/1/2020 40 40 16
17 8/5/2020 48.7 48.7 17
18 9/29/2020 47.7 47.7 18
19 10/14/2020 41.7 41.7 19
20 11/2/2020 50.2 50.2 20
21 11/5/2020 47 47 21
22 12/9/2020 47.3 47.3 22
23 1/6/2021 418 418 23
24 2/3/2021 43.7 43.7 24
25 3/3/2021 48.2 48.2 25
26 4/7/2021 43.1 43.1 26
27 5/11/2021 41.9 41.9 27
28 5/26/2021 45 45 28
29 5/27/2021 37.7 37.7 29
30 6/2/2021 43.2 43.2 30
31 7/9/2021 43.1 43.1 31
32 8/2/2021 38.2 38.2 32
33 8/26/2021 44.1 44.1 33
34 9/3/2021 44.9 44.9 34
35 10/1/2021 49.3 49.3 35
36 11/3/2021 44.4 44.4 36
37 11/10/2021 45.1 45.1 37
38 12/1/2021 40.7 40.7 38
39 1/5/2022 44.5 44.5 39
40 2/2/2022 41.6 41.6 40
41 2/10/2022 44.3 44.3 41
42 3/2/2022 42.5 42.5 42
43 4/1/2022 42.4 42.4 43
44 5/4/2022 48.4 48.4 44
45 6/6/2022 40.2 40.2 45
46 7/5/2022 35.6 35.6 46
47 8/4/2022 37.7 37.7 47
48 8/23/2022 37.5 37.5 48
49 9/2/2022 45 45 49
50 10/3/2022 37.5 37.5 50
51 11/1/2022 42.5 42.5 51
52 11/8/2022 41.3 41.3 52
53 12/1/2022 46.1 46.1 53
54 1/3/2023 34.4 34.4 54
55 2/6/2023 39.8 39.8 55
56 2/9/2023 46.1 46.1 56
57 3/1/2023 45.2 45.2 57
58 4/3/2023 38.9 38.9 58
24911 RPA, data
- 1 - 6/26/2023

REASONABLE POTENTIAL ANALYSIS
Par01 & Par02
Use"PASTE SPECIAL
Arsenic Values"then"COPY"
Maximum data
points=58
Date Data BDL=1/2DL Results
1 2/26/2019 < 10 5 Std Dev. 4.6988
2 2/27/2019 < 10 5 Mean 5.9318
3 5/8/2019 < 10 5 C.V. 0.7921
4 5/9/2019 < 10 5 n 22
5 8/6/2019 < 10 5
6 8/7/2019 < 10 5 Mult Factor= 1.42
7 11/5/2019 < 10 5 Max. Value 25.0 ug/L
8 11/7/2019 < 10 5 Max. Pred Cw 35.5 ug/L
9 2/18/2020 < 10 5
10 5/14/2020 < 10 5
11 6/3/2020 < 10 5
12 8/5/2020 < 10 5
13 11/5/2020 < 10 5
14 5/11/2021 < 10 5
15 5/27/2021 < 10 5
16 8/26/2021 < 10 5
17 11/10/2021 < 10 5
18 2/10/2022 < 10 5
19 5/11/2022 < 1 0.5
20 8/23/2022 < 5 2.5
21 11/8/2022 < 25 12.5
22 2/9/2023 < 50 25
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
24911 RPA, data
-2 - 6/26/2023

REASONABLE POTENTIAL ANALYSIS
Par03 Par04
Use"PASTE SPECIAL Use"PASTE SPECIAL
Beryllium Values"then"COPY" Cadmium Values"then"COPY"
Maximum data .Maximum data
points=58 points=58
Date Data BDL=1/2DL Results Date Data BDL=1/2DL Results
1 2/26/2019 < 1 0.5 Std Dev. 0.4364 1 2/26/2019 < 1 0.5 Std Dev. 0.4482
2 2/27/2019 < 1 0.5 Mean 0.5952 2 2/27/2019 < 1 0.5 Mean 0.6250
3 5/8/2019 < 1 0.5 C.V. 0.7332 3 5/8/2019 < 1 0.5 C.V. 0.7171
4 5/9/2019 < 1 0.5 n 21 4 5/9/2019 < 1 0.5 n 22
5 8/6/2019 < 1 0.5 5 8/6/2019 < 1 0.5
6 8/7/2019 < 1 0.5 Mult Factor= 1.42 6 8/7/2019 < 1 0.5 Mult Factor= 1.38
7 11/5/2019 < 1 0.5 Max. Value 2.50 ug/L 7 11/5/2019 < 1 0.5 Max. Value 2.500 ug/L
8 11/7/2019 < 1 0.5 Max. Pred Cw 3.55 ug/L 8 11/7/2019 < 1 0.5 Max. Pred Cw 3.450 ug/L
9 2/18/2020 < 1 0.5 9 2/18/2020 < 1 0.5
10 5/14/2020 < 1 0.5 10 5/14/2020 < 1 0.5
11 6/3/2020 < 1 0.5 11 6/3/2020 < 1 0.5
12 8/5/2020 < 1 0.5 12 8/5/2020 < 1 0.5
13 11/5/2020 < 1 0.5 13 11/5/2020 < 1 0.5
14 5/11/2021 < 1 0.5 14 5/11/2021 < 1 0.5
15 5/27/2021 < 1 0.5 15 5/27/2021 < 1 0.5
16 8/26/2021 < 1 0.5 16 8/26/2021 < 1 0.5
17 11/10/2021 < 1 0.5 17 11/10/2021 < 1 0.5
18 2/10/2022 < 1 0.5 18 2/10/2022 < 1 0.5
19 5/4/2022 < 1 0.5 19 5/4/2022 < 1 0.5
20 5/11/2022 < 1 0.5 20 5/11/2022 < 1 0.5
21 2/9/2023 < 5 2.5 21 11/8/2022 < 2.5 1.25
22 22 2/9/2023 < 5 2.5
23 23
24 24
25 25
26 26
27 27
28 28
29 29
30 30
31 31
32 32
33 33
34 34
35 35
36 36
37 37
38 38
39 39
40 40
41 41
42 42
43 43
44 44
45 45
46 46
47 47
48 48
49 49
50 50
51 51
52 52
53 53
54 54
55 55
56 56
57 57
58 58
24911 RPA, data
-3- 6/26/2023

REASONABLE POTENTIAL ANALYSIS
Par10 Pal
Use"PASTE SPECIAL Use"PASTE SPECIAL
Chromium, Total Values"then"COPY" Copper Values"then"COPY"
Maximum data .Maximum data
points=58 points=58
Date Data BDL=1/2DL Results Date Data BDL=1/2DL Results
1 2/26/2019 < 5 2.5 Std Dev. 5.0766 1 2/26/2019 7.4 7.4 Std Dev. 3.8760
2 2/27/2019 < 5 2.5 Mean 4.1087 2 2/27/2019 7.3 7.3 Mean 9.7348
3 5/8/2019 < 5 2.5 C.V. 1.2356 3 5/8/2019 11 11 C.V. 0.3982
4 5/9/2019 < 5 2.5 n 23 4 5/9/2019 9 9 n 23
5 8/6/2019 < 5 2.5 5 8/6/2019 8.4 8.4
6 8/7/2019 < 5 2.5 Mult Factor= 1.59 6 8/7/2019 9.7 9.7 Mult Factor= 1.20
7 11/5/2019 < 5 2.5 Max. Value 25.0 pg/L 7 11/5/2019 7.3 7.3 Max. Value 25.00 ug/L
8 11/7/2019 < 5 2.5 Max. Pred Cw 39.8 pg/L 8 11/7/2019 8 8 Max. Pred Cw 30.00 ug/L
9 2/18/2020 < 5 2.5 9 2/18/2020 7.2 7.2
10 5/14/2020 < 5 2.5 10 5/14/2020 8.6 8.6
11 6/3/2020 < 5 2.5 11 6/3/2020 7.2 7.2
12 8/5/2020 7 7 12 8/5/2020 7.3 7.3
13 11/5/2020 < 5 2.5 13 11/5/2020 7.9 7.9
14 5/11/2021 < 5 2.5 14 5/11/2021 13.3 13.3
15 5/27/2021 < 5 2.5 15 5/27/2021 9.6 9.6
16 8/26/2021 < 5 2.5 16 8/26/2021 8 8
17 11/10/2021 < 5 2.5 17 11/10/2021 11 11
18 2/10/2022 < 5 2.5 18 2/10/2022 8.8 8.8
19 5/4/2022 < 5 2.5 19 5/4/2022 13.7 13.7
20 5/11/2022 < 5 2.5 20 5/11/2022 8.6 8.6
21 8/23/2022 < 5 2.5 21 8/23/2022 7.1 7.1
22 11/8/2022 < 25 12.5 22 11/8/2022 < 25 12.5
23 2/9/2023 < 50 25 23 2/9/2023 < 50 25
24 24
25 25
26 26
27 27
28 28
29 29
30 30
31 31
32 32
33 33
34 34
35 35
36 36
37 37
38 38
39 39
40 40
41 41
42 42
43 43
44 44
45 45
46 46
47 47
48 48
49 49
50 50
51 51
52 52
53 53
54 54
55 55
56 56
57 57
58 58
24911 RPA, data
-4- 6/26/2023

REASONABLE POTENTIAL ANALYSIS
Par12 Par14
Use"PASTE SPECIAL Use"PASTE SPECIAL
Cyanide Values"then"COPY" Lead Values"then"COPY"
Maximum data .Maximum data
points=58 points=58
Date Data BDL=1/2DL Results Date BDL=1/2DL Results
1 2/26/2019 < 8 5 Std Dev. 0.0000 1 2/26/2019 < 5 2.5 Std Dev. 0.6822
2 2/27/2019 < 8 5 Mean 5.00 2 2/27/2019 < 5 2.5 Mean 2.5217
3 8/6/2019 < 8 5 C.V. 0.0000 3 5/8/2019 < 5 2.5 C.V. 0.2705
4 8/7/2019 < 8 5 n 19 4 5/9/2019 < 5 2.5 n 23
5 11/5/2019 < 8 5 5 8/6/2019 < 5 2.5
6 11/7/2019 < 8 5 Mult Factor= 1.00 6 8/7/2019 < 5 2.5 Mult Factor= 1.14
7 2/18/2020 < 8 5 Max. Value 5.0 ug/L 7 11/5/2019 < 5 2.5 Max. Value 5.000 ug/L
8 5/14/2020 < 8 5 Max. Pred Cw 5.0 ug/L 8 11/7/2019 < 5 2.5 Max. Pred Cw 5.700 ug/L
9 6/3/2020 < 8.0 5 9 2/18/2020 < 5 2.5
10 8/5/2020 < 8.0 5 10 5/14/2020 < 5 2.5
11 11/5/2020 < 8 5 11 6/3/2020 < 5 2.5
12 5/11/2021 < 8 5 12 8/5/2020 < 5 2.5
13 5/27/2021 < 8 5 13 11/5/2020 < 5 2.5
14 8/26/2021 < 8 5 14 5/11/2021 < 5 2.5
15 11/10/2021 < 8 5 15 5/27/2021 < 5 2.5
16 2/10/2022 < 8 5 16 8/26/2021 < 5 2.5
17 5/4/2022 < 8 5 17 11/10/2021 < 5 2.5
18 11/8/2022 < 8 5 18 2/10/2022 < 5 2.5
19 2/9/2023 < 8 5 19 5/4/2022 < 5 2.5
20 20 5/11/2022 < 5 2.5
21 21 8/23/2022 < 1 0.5
22 22 11/8/2022 < 5 2.5
23 23 2/9/2023 < 10 5
24 24
25 25
26 26
27 27
28 28
29 29
30 30
31 31
32 32
33 33
34 34
35 35
36 36
37 37
38 38
39 39
40 40
41 41
42 42
43 43
44 44
45 45
46 46
47 47
48 48
49 49
50 50
51 51
52 52
53 53
54 54
55 55
56 56
57 57
58 58
24911 RPA, data
- 5- 6/26/2023

REASONABLE POTENTIAL ANALYSIS
Par17 & Par18 use"PASTE Par19
SPECIAL- Use"PASTE SPECIAL-
Values"then Values"then"COPY".
Nickel "COPY". Selenium Maximum data points
Maximum data =58
Date Data BDL=1/2DL Results points=58 Date Data BDL=1/2DL Results
1 2/26/2019 < 5 2.5 Std Dev. 5.0314 1 2/26/2019 < 10 5 Std Dev. 1.7094
2 2/27/2019 < 5 2.5 Mean 4.5543 2 2/27/2019 < 10 5 Mean 5.2273
3 5/8/2019 < 5 2.5 C.V. 1.1048 3 5/8/2019 < 10 5 C.V. 0.3270
4 5/9/2019 < 6.3 3.15 n 23 4 5/9/2019 < 10 5 n 22
5 8/6/2019 < 5.3 2.65 5 8/6/2019 < 10 5
6 8/7/2019 < 5 2.5 Mult Factor= 1.54 6 8/7/2019 < 10 5 Mult Factor= 1.17
7 11/5/2019 < 6.7 3.35 Max. Value 25.0 pg/L 7 11/5/2019 < 10 5 Max. Value 12.5 ug/L
8 11/7/2019 < 5.7 2.85 Max. Pred Cw 38.5 pg/L 8 11/7/2019 < 10 5 Max. Pred Cw 14.6 ug/L
9 2/18/2020 < 5 2.5 9 2/18/2020 < 10 5
10 5/14/2020 < 5 2.5 10 5/14/2020 < 10 5
11 6/3/2020 < 9.5 4.75 11 6/3/2020 < 10 5
12 8/5/2020 < 7.9 3.95 12 8/5/2020 < 10 5
13 11/5/2020 < 5 2.5 13 11/5/2020 < 10 5
14 5/11/2021 < 5 2.5 14 5/11/2021 < 10 5
15 5/27/2021 < 5 2.5 15 5/27/2021 < 10 5
16 8/26/2021 < 6.7 3.35 16 8/26/2021 < 10 5
17 11/10/2021 < 17 8.5 17 11/10/2021 < 10 5
18 2/10/2022 < 8 4 18 2/10/2022 < 10 5
19 5/4/2022 < 5.3 2.65 19 5/4/2022 < 10 5
20 5/11/2022 < 6.1 3.05 20 5/11/2022 < 10 5
21 8/23/2022 < 5 2.5 21 8/23/2022 < 5 2.5
22 11/8/2022 < 25 12.5 22 11/8/2022 < 25 12.5
23 2/9/2023 < 50 25 23
24 24
25 25
26 26
27 27
28 28
29 29
30 30
31 31
32 32
33 33
34 34
35 35
36 36
37 37
38 38
39 39
40 40
41 41
42 42
43 43
44 44
45 45
46 46
47 47
48 48
49 49
50 50
51 51
52 52
53 53
54 54
55 55
56 56
57 57
58 58
24911 RPA, data
-6- 6/26/2023

REASONABLE POTENTIAL ANALYSIS
Par20 Par21
Use"PASTE SPECIAL Use"PASTE SPECIAL-
Silver Values"then"COPY" Zinc Values"then"COPY"
Maximum data .Maximum data
points=58 points=58
Date Data BDL=1/2DL Results Date Data BDL=1/2DL Results
1 2/26/2019 < 5 2.5 Std Dev. 1.0983 1 2/26/2019 42 42 Std Dev. 13.5776
2 2/27/2019 < 5 2.5 Mean 1.1114 2 2/27/2019 89 89 Mean 49.0261
3 5/8/2019 < 5 2.5 C.V. 0.9882 3 5/8/2019 61 61 C.V. 0.2769
4 5/9/2019 < 5 2.5 n 22 4 5/9/2019 75 75 n 23
5 8/6/2019 < 5 2.5 5 8/6/2019 41 41
6 8/7/2019 < 5 2.5 Mult Factor= 1.52 6 8/7/2019 43 43 Mult Factor= 1.14
7 11/5/2019 < 0.4 0.2 Max. Value 2.500 ug/L 7 11/5/2019 37 37 Max. Value 89.0 ug/L
8 11/7/2019 < 0.4 0.2 Max. Pred Cw 3.800 ug/L 8 11/7/2019 45 45 Max. Pred Cw 101.5 ug/L
9 2/18/2020 < 2 1 9 2/18/2020 42 42
10 5/14/2020 < 5 2.5 10 5/14/2020 39.1 39.1
11 6/3/2020 < 0.5 0.25 11 6/3/2020 41 41
12 8/5/2020 < 2 1 12 8/5/2020 43 43
13 11/5/2020 < 0.4 0.2 13 11/5/2020 41 41
14 5/11/2021 < 0.4 0.2 14 5/11/2021 52 52
15 5/27/2021 < 0.4 0.2 15 5/27/2021 42 42
16 8/26/2021 < 0.4 0.2 16 8/26/2021 41 41
17 11/10/2021 < 0.4 0.2 17 11/10/2021 68 68
18 2/10/2022 < 0.4 0.2 18 2/10/2022 42 42
19 5/4/2022 < 0.4 0.2 19 5/4/2022 64 64
20 5/11/2022 < 0.4 0.2 20 5/11/2022 39 39
21 8/23/2022 < 5 2.5 21 8/23/2022 37.2 37.2
22 11/8/2022 < 0.4 0.2 22 11/8/2022 53.3 53.3
23 23 2/9/2023 < 100 50
24 24
25 25
26 26
27 27
28 28
29 29
30 30
31 31
32 32
33 33
34 34
35 35
36 36
37 37
38 38
39 39
40 40
41 41
42 42
43 43
44 44
45 45
46 46
47 47
48 48
49 49
50 50
51 51
52 52
53 53
54 54
55 55
56 56
57 57
58 58
24911 RPA, data
-7- 6/26/2023

French Broad River WRF > Outfall 001
NCO024911 Freshwater RPA - 95% Probability/95% Confidence Using Metal Translators QW = 40 MGD
MAXIMUM DATA POINTS = 58
Qw (MGD) = 40.0000 WWTP/WTP Class: IV COMBINED HARDNESS (mg/L)
1Q10S (cfs) = 376.30 IWC% @ 1Q10S = 14.1455624 Acute = 28.82 mg/L
7QIOS (cfs) = 466.00 IWC% @ 7QI OS = 11.74242424 Chronic= 28.17 mg/L
7Q10W (cfs) = 595.00 IWC% @ 7Q10W= 9.436834094
30Q2 (cfs) = 882.00 IWC% @ 30Q2 = 6.56779661
Avg. Stream Flow, QA(cfs) = 2140.00 IW%C @ QA= 2.815622162
Receiving Stream: French Broad River HUC 06010105 Stream Class: B
PARAMETER NC STANDARDS OR EPA CRITERIA J co REASONABLE POTENTIAL RESULTS RECOMMENDED ACTION
TYPE Aplied
Chronic Standard Acute D n #Det. Max Pred Cw Allowable Cw
Acute (FW): 2,403.6
Arsenic C 150 FW(7QIOs) 340 ug/L
22 0 35.5 Chronic (FW):--- 1,277.4 - -----------------------------
Ma_x MDL_= 50____
Arsenic C 10 HH/WS(Qavg) ug/L NO DETECTS Chronic (HH): 355.2 No RP, Predicted Max< 50% of Allowable Cw- No
Max MDL 50 Monitoring required
Acute: 459.51
Beryllium NC 6.5 FW(7Q10s) 65 ug/L 21 0 3.55
Chronic: ---- 55.35-- -----------------------------
NO DETECTS Max MDL= 5
Acute: 25.932
Cadmium NC 0.6457 FW(7Q10s) 3.6682 ug/L 22 0 3.450
Chronic: 5.499 No RP, Predicted Max< 50% of Allowable Cw- No
NO DETECTS Max MDL= 5 Monitoring required
Acute: 7,189.1
Chromium III NC 129.84 FW(7Q10s) 1016.94 µg/L 0 0 N/A
Chronic: 1,105.7
Acute: 113.1
Chromium VI NC 11 FW(7Q10s) 16 µg/L 0 0 N/A
Chronic: 93.7
Tot Cr value(s) > 5 but< Cr VI Allowable Cw a: No monitoring required if all Total Chromium
Chromium, Total NC µg/L 23 1 39.8 Max reported value = 25 samples are < 5 pg/L or Pred. max for Total Cr is <
allowable Cw for Cr VI.
Acute: 84.65
Copper NC 8.7278 FW(7Q10s) 11.9743 ug/L 23 21 30.00
Chronic: 74.33 No RP, Predicted Max< 50% of Allowable Cw- No
No value >Allowable Cw Monitoring required
Acute: 155.5
Cyanide NC 5 FW(701Os) 22 10 u�2/L 19 0 5.0 _
-----------------------------
No RP, Predicted Max< 50% of Allowable Cw- No
NO DETECTS Max MDL 10 Monitoring required
Acute: 626.253
Lead NC 3.3649 FW(7Q10s) 88.5870 ug/L 23 0 5.700
Chronic: 28.656 No RP, Predicted Max< 50% of Allowable Cw- No
NO DETECTS Max MDL= 10 Monitoring required
24911 RPA, rpa
Page 1 of 2 6/26/2023

French Broad River WRF > Outfall 001
NCO024911 Freshwater RPA - 95% Probability/95% Confidence Using Metal Translators Qw = 40 MGD
Acute (FW): 2,672.8
Nickel NC 41.1919 FW(7Q10s) 378.0860 µg/L
23 0 38.5 Chronic (FW): 350.8 No RP, Predicted Max< 50% of Allowable Cw- No
Max MDL= 50 Monitoring required
Nickel NC 25.0000 WS(7Q10s) µg/L NO DETECTS Chronic (WS): 212.9
Max MDL 50
Acute: 395.9
Selenium NC 5 FW(7Q10s) 56 ug/L 22 0 14.6
Chronic: 42.6 No RP, Predicted Max< 50% of Allowable Cw- No
NO DETECTS Max MDL 25 Monitoring required
Acute: 2.676
Silver NC 0.06 FW(7Q10s) 0.3786 ug/L 22 0 3.800
Chronic: 0.511 All values non-detect< 5 ug/L, < 2 ug/L and < 0.4
ug/L- No Monitoring required; Permittee shall use
NO DETECTS Max MDL 5 sufficiently sensitive test methods
Acute: 1,002.5 No RP, Predicted Max< 50% of Allowable Cw- No
Zinc NC 140.2366 FW(7Q10s) 141.8107 ug/L 23 22 101.5 Monitoring required
----- -- - -----------------------------
Chronic 1,
No value > Allowable Cw
24911 RPA, rpa
Page 2 of 2 6/26/2023

Permit No. NCO024911
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 Q ality Standards/A uatic Life Protection
Parameter Acute FW, µg/l Chronic FW, µg/l Acute SW, µg/1 Chronic SW, µg/1
(Dissolved) (Dissolved) (Dissolved) (Dissolved)
Arsenic 340 150 69 36
Beryllium 65 6.5 --- ---
Cadmium Calculation Calculation 40 8.8
Chromium III Calculation Calculation --- ---
Chromium VI 16 11 1100 50
Copper Calculation Calculation 4.8 3.1
Lead Calculation Calculation 210 8.1
Nickel Calculation Calculation 74 8.2
Silver Calculation 0.06 1.9 0.1
Zinc Calculation Calculation 90 81
Table 1 Notes:
1. FW=Freshwater, SW= Saltwater
2. Calculation=Hardness dependent 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/1 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/I
Cadmium,Acute WER*{1.136672-[ln hardness](0.041838)} e^10.9151 [ln hardness]-3.1485}
Cadmium,Acute Trout waters WER*{1.136672-[ln hardness](0.041838)} e^{0.9151[In hardness]-3.62361
Cadmium,Chronic WER*{1.101672-[ln hardness](0.041838)} •e^{0.7998[ln hardness]-4.445 11
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}
Page 1 of 4

Permit No. NCO024911
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/WOBELs 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 1 Q 10 using the formula 1 Q 10=0.843 (s7Q 10, 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.
Page 2 of 4

Permit No. NCO024911
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 IQ 10 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.
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 I + { [Kpo] [ss('+a)] [10-6] }
Where:
ss=in-stream suspended solids concentration [mg/1],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.
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=(s7Q 10+Qw)(Cwgs)—(s7Q 10) (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 s7Q 10)
s7Q 10=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 s7Q 10 may be incorporated as applicable:
IQ 10=used in the equation to protect aquatic life from acute toxicity
Page 3 of 4

Permit No. NC0024911
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) 52.02 Average from 812019 to 412023
[Total as, CaCO3 or(Ca+Mg)] samples
Average Upstream Hardness (mg/L) 25 Default value used;Average
[Total as, CaCO3 or(Ca+Mg)] upstream hardness< 25 mg/L
7Q10 summer(cfs) 466.0 Historical;Previous Fact Sheet
1Q10(cfs) 376.3 Calculated in RPA
Permitted Flow(MGD) 40.0 NPDES Files
Date: 7/24/2023
Permit Writer: Nick Coco
Page 4 of 4

NCO024911 French Broad River WRF 6/26/2023
CBOD monthly removal rate TSS monthly removal rate
Month RR(%) Month RR (%) Month RR(%) Month RR(%)
January-19 89.53 July-21 92.64 January-19 89.69 July-21 94.63
February-19 90.17 August-21 92.43 February-19 91.79 August-21 92.94
March-19 92.72 September-21 93.37 March-19 95.83 September-21 95.04
April-19 90.19 October-21 92.82 April-19 94.88 October-21 94.31
May-19 93.02 November-21 92.80 May-19 95.54 November-21 94.98
June-19 93.74 December-21 91.94 June-19 96.04 December-21 94.49
July-19 93.46 January-22 94.11 July-19 95.55 January-22 94.62
August-19 94.55 February-22 93.32 August-19 96.35 February-22 92.22
September-19 95.16 March-22 91.75 September-19 96.52 March-22 91.99
October-19 95.13 April-22 94.16 October-19 96.95 April-22 95.78
November-19 94.54 May-22 90.55 November-19 94.90 May-22 94.93
December-19 93.03 June-22 93.09 December-19 93.28 June-22 94.60
January-20 91.89 July-22 93.68 January-20 91.33 July-22 95.64
February-20 89.10 August-22 92.22 February-20 87.90 August-22 95.72
March-20 92.00 September-22 93.06 March-20 93.29 September-22 96.40
April-20 92.46 October-22 92.81 April-20 92.58 October-22 95.29
May-20 91.23 November-22 94.56 May-20 92.02 November-22 95.41
June-20 93.26 December-22 88.26 June-20 94.07 December-22 91.67
July-20 93.36 January-23 91.31 July-20 94.29 January-23 91.95
August-20 92.98 February-23 93.34 August-20 94.74 February-23 93.46
September-20 93.15 March-23 94.72 September-20 94.09 March-23 95.19
October-20 93.89 April-23 93.34 October-20 94.32 April-23 95.69
November-20 92.32 May-23 November-20 93.88 May-23
December-20 92.44 June-23 December-20 94.08 June-23
January-21 92.90 July-23 January-21 93.00 July-23
February-21 88.97 August-23 February-21 90.72 August-23
March-21 92.79 September-23 March-21 90.80 September-23
April-21 91.61 October-23 April-21 92.18 October-23
May-21 92.29 November-23 May-21 92.20 November-23
June-21 92.82 December-23 June-21 94.31 December-23
Overall BOD removal rate 92.60 Overall TSS removal rate 93.92

6/26/23 WQS= 12 ng/L MERCURY WQBEL/TBEL EVALUATION V:2013-6
Facility Name
French Broad River WRF/NC0024911 No Limit Required
/Permit No.
MMP Required
Total Mercury 1631E PQL=0.5 ng/L 7Q10s = 466.000 cfs WQBEL= 102.19 ng/L
Date Modifier Data Entry Value Permitted Flow= 40.000 47 ng/L
8/6/19 10.9 10.9
8/7/19 0.891 0.891
11/5/19 12.5 12.5
11/7/19 9.51 9.51 8.5 ng/L-Annual Average for 2019
2/18/20 9.85 9.85
5/14/20 10.2 10.2
6/3/20 8.32 8.32
8/5/20 9.05 9.05
11/5/20 8.99 8.99 9.3 ng/L-Annual Average for 2020
5/11/21 18 18
5/27/21 26.1 26.1 22.1 ng/L-Annual Average for 2021
8/23/22 < 0.2 0.5 0.5 ng/L-Annual Average for 2022
2/9/23 28.2 28.2 28.2 ng/L-Annual Average for 2023

French Broad River WRF/NC0024911
Mercury Data Statistics (Method 1631E)
2019 2020 2021 2022 2023
#of Samples 4 5 2 1 1
Annual Average, ng/L 8.5 9.3 22.1 0.50 28.2
Maximum Value, ng/L 12.50 10.20 26.10 0.5 28.2
TBEL, ng/L 47
WQBEL, ng/L 102.2

NH3/TRC WLA Calculations
Facility: French Broad River WRF Receiving water pH(upstream-summer) 7.60
Permit No. NC0024911 Receiving water pH (upstream-winter) 7.35
Prepared By: N. Coco
Temperature (upstream-summer) 23.2
Use Site Specific(FW, SW) Yes Temperature (upstream-winter) 11.9
Receiving Water Class FW If SW or FW-SW,salinity(ppt-summer)
Supplemental Class If SW or FW-SW,salinity(ppt-winter)
WS Classification (if needed) Use Site Specific upstream ammonia Yes
Location (no site spec temp.) Bkgd ammonia (upstream-summer) 0.050
Use Site Specific pH IYes Bkgd ammonia (upstream-winter) 0.190
Is Class PNA/HQW
Effluent Temperature (Summer) 23.3 pH (mixed-summer) 7.58
Effluent Temperature (Winter) 17.8 # pH (mixed-winter) 7.36
Effluent pH (Summer) 7.47 Temperature (mixed-summer) 23.21
Effluent pH (Winter) 7.47 Temperature (mixed-winter) 12.59
Enter Design Flow(MGD): 40
Enter s7Q10 (cfs): 466
Enter w7Q10 (cfs): 595
Total Residual Chlorine(TRC) Ammonia(Summer)
Daily Maximum Limit(ug/1) Monthly Average Limit(mg NH3-N/1)
s7Q10 (CFS) 466 s7Q10 (CFS) 466
DESIGN FLOW(MGD) 40 DESIGN FLOW(MGD) 40
DESIGN FLOW(CFS) 62 DESIGN FLOW(CFS) 62
STREAM STD (UG/L) 17.0 INSTREAM STD (MG/L) 1.0
Upstream Bkgd (ug/1) 0 Upstream Bkgd (mg/1) 0.05
IWC (%) 11.74 IWC (%) 11.74
Allowable Conc. (ug/1) 145 Allowable Monthly Conc. (mg/I) 8.5
Allowable Weekly Con. (mg/1) 21.4 2.5 X
Fecal Coliform Ammonia(Winter)
Monthly Average Limit: 200/100m1 Monthly Average Limit(mg NH3-N/1)
(If DF >331; Monitor)
(If DF<331; Limit) w7Q10 (CFS) 595
Dilution Factor(DF) 8.52 DESIGN FLOW(MGD) 40
DESIGN FLOW(CFS) 62
INSTREAM STD (MG/L) 2.5
Upstream Bkgd (mg/1) 0.190
IWC (%) 9.44
Allowable Monthly Conc. (mg/I) 24.7
Allowable Weekly Conc. (mg/1) 61.8 2.5 X
If ammonia toxicity is limiting,winter ammonia(NH3-N) limits cannot exceed twice summer(15A NCAC 2B .0404(c)):
Total Residual Chlorine I
1. Cap Daily Max limit at 28 ug/I to protect for acute toxicity

Summer Winter Ammonia
pH Temp pH Temp Summer Winter
Effluent 90th 7.47 23.3 7.47 17.8
Upstream 90th 7.60 23.2 7.35 11.9 0.05 0.19

MONITORING REPORT(MR)VIOLATIONS for: Report Date: 06/22/22 Page 1 of 4
Permit: NCO024911 MRS Betweel 6 - 2018 and 6 - 2023 Region: % Violation Category:Limit Violation Program Category:
Facility Name:% Param Nam(% County: % Subbasin:% Violation Action:%
Major Minor: %
PERMIT: NCO024911 FACILITY: Metropolitan Sewerage District of Buncombe County COUNTY: Buncombe REGION: Asheville
North Carolina-French Broad River WRF
Limit Violation
MONITORING VIOLATION UNIT OF CALCULATED %
REPORT OUTFALL LOCATION PARAMETER DATE FREQUENCY MEASURE LIMIT VALUE Over VIOLATION TYPE VIOLATION ACTION
02-2021 001 Effluent BOD,Carbonaceous 05 Day, 02/13/21 5 X week mg/I 40 41.46 3.6 Weekly Average Proceed to NOV
20 C Exceeded
08-2018 001 Effluent Chlorine,Total Residual 08/16/18 5 X week ug/I 28 43 53.6 Daily Maximum No Action, BPJ
Exceeded
11-2018 001 Effluent Chlorine,Total Residual 11/15/18 5 X week ug/I 28 110 292.9 Daily Maximum Proceed to NOV
Exceeded
06-2018 001 Effluent Coliform, Fecal MF, MFC 06/02/18 5 X week #/100ml 400 2,420 505 Weekly Geometric Mean No Action, BPJ
Broth,44.5 C Exceeded
10-2018 MW3/CONVO02935 Barium,Total(as Ba) 10/31/18 3 X year mg/I 700 40,700 5,714.3 Limit Exceeded No Action,Data
Entry Error
01-2019 MW3/CONVO02935 Barium,Total(as Ba) 01/31/19 3 X year mg/I 700 38,300 5,371.4 Limit Exceeded No Action,Data
Entry Error
06-2018 MW4/CONVO03466 Barium,Total(as Ba) 06/30/18 3 X year mg/I 700 6,438 819.7 Limit Exceeded No Action,Data
Entry Error
10-2018 MW4/CONVO03466 Barium,Total(as Ba) 10/31/18 3 X year mg/I 700 57,600 8,128.6 Limit Exceeded No Action,Data
Entry Error
06-2018 MW4/CONVO03466 Nitrogen,Ammonia Total(as 06/30/18 3 X year ug/I 1,500 1,700 13.3 Limit Exceeded No Action, BPJ
N)
01-2019 MW4/CONVO03466 Nitrogen,Ammonia Total(as 01/31/19 3 X year ug/I 1,500 2,200 46.7 Limit Exceeded No Action, BPJ
N)
01-2020 MW-5/BIMS052231 Iron,Total(as Fe) 01/31/20 3 X year ug/I 300 524 74.7 Limit Exceeded No Action, BPJ
06-2022 MW-5/BIMS052231 Iron,Total(as Fe) 06/30/22 3 X year ug/I 300 382 27.3 Limit Exceeded No Action, BPJ
06-2019 MW-5/BIMS052231 Manganese,Total(as Mn) 06/30/19 3 X year ug/I 50 482 864 Limit Exceeded No Action, BPJ
10-2019 MW-5/BIMS052231 Manganese,Total(as Mn) 10/31/19 3 X year ug/I 50 302 504 Limit Exceeded No Action, BPJ
01-2020 MW-5/BIMS052231 Manganese,Total(as Mn) 01/31/20 3 X year ug/I 50 533 966 Limit Exceeded No Action, BPJ
06-2022 MW-5/BIMS052231 Manganese,Total(as Mn) 06/30/22 3 X year ug/I 50 76.2 52.4 Limit Exceeded No Action, BPJ
10-2022 MW-6R/BIMS052233 Chromium,Total(as Cr) 10/31/22 3 X year ug/I 10 17.4 74.0 Limit Exceeded None

MONITORING REPORT(MR)VIOLATIONS for: Report Date: 06/22/22 Page 2 of 4
Permit: NCO024911 MRS Betweel 6 - 2018 and 6 - 2023 Region: % Violation Category:Limit Violation Program Category:
Facility Name:% Param Nam(% County: % Subbasin:% Violation Action:%
Major Minor: %
PERMIT: NCO024911 FACILITY: Metropolitan Sewerage District of Buncombe County COUNTY: Buncombe REGION: Asheville
North Carolina-French Broad River WRF
Limit Violation
MONITORING VIOLATION UNIT OF CALCULATED %
REPORT WELL LOCATION PARAMETER DATE FREQUENCY MEASURE LIMIT VALUE Over VIOLATION TYPE VIOLATION ACTION
06-2019 MW-6R/BIMS052233 Iron,Total(as Fe) 06/30/19 3 X year ug/I 300 7,480 2,393.3 Limit Exceeded No Action, BPJ
10-2019 MW-6R/BIMS052233 Iron,Total(as Fe) 10/31/19 3 X year ug/I 300 50,800 16,833.3 Limit Exceeded No Action, BPJ
01-2020 MW-6R/BIMS052233 Iron,Total(as Fe) 01/31/20 3 X year ug/I 300 43,000 14,233.3 Limit Exceeded No Action, BPJ
06-2020 MW-6R/BIMS052233 Iron,Total(as Fe) 06/30/20 3 X year ug/I 300 1,820 506.7 Limit Exceeded No Action, BPJ
10-2020 MW-6R/BIMS052233 Iron,Total(as Fe) 10/31/20 3 X year ug/I 300 5,410 1,703.3 Limit Exceeded No Action, BPJ
01-2021 MW-6R/BIMS052233 Iron,Total(as Fe) 01/31/21 3 X year ug/I 300 1,250 316.7 Limit Exceeded No Action, BPJ
06-2021 MW-6R/BIMS052233 Iron,Total(as Fe) 06/30/21 3 X year ug/I 300 5,360 1,686.7 Limit Exceeded No Action, BPJ
10-2021 MW-6R/BIMS052233 Iron,Total(as Fe) 10/31/21 3 X year ug/I 300 1,080 260 Limit Exceeded No Action, BPJ
01-2022 MW-6R/BIMS052233 Iron,Total(as Fe) 01/31/22 3 X year ug/I 300 9,200 2,966.7 Limit Exceeded No Action, BPJ
06-2022 MW-6R/BIMS052233 Iron,Total(as Fe) 06/30/22 3 X year ug/I 300 16,900 5,533.3 Limit Exceeded No Action, BPJ
10-2022 MW-6R/BIMS052233 Iron,Total(as Fe) 10/31/22 3 X year ug/I 300 34,800 11,500 Limit Exceeded None
06-2019 MW-6R/BIMS052233 Manganese,Total(as Mn) 06/30/19 3 X year ug/I 50 14,100 28,100 Limit Exceeded No Action, BPJ
10-2019 MW-6R/BIMS052233 Manganese,Total(as Mn) 10/31/19 3 X year ug/I 50 12,700 25,300 Limit Exceeded No Action, BPJ
01-2020 MW-6R/BIMS052233 Manganese,Total(as Mn) 01/31/20 3 X year ug/I 50 10,000 19,900 Limit Exceeded No Action, BPJ
06-2020 MW-6R/BIMS052233 Manganese,Total(as Mn) 06/30/20 3 X year ug/I 50 7,880 15,660 Limit Exceeded No Action, BPJ
10-2020 MW-6R/BIMS052233 Manganese,Total(as Mn) 10/31/20 3 X year ug/I 50 9,330 18,560 Limit Exceeded No Action, BPJ
01-2021 MW-6R/BIMS052233 Manganese,Total(as Mn) 01/31/21 3 X year ug/I 50 8,510 16,920 Limit Exceeded No Action, BPJ
10-2021 MW-6R/BIMS052233 Manganese,Total(as Mn) 10/31/21 3 X year ug/I 50 6,690 13,280 Limit Exceeded No Action, BPJ
01-2022 MW-6R/BIMS052233 Manganese,Total(as Mn) 01/31/22 3 X year ug/I 50 12,300 24,500 Limit Exceeded No Action, BPJ

MONITORING REPORT(MR)VIOLATIONS for: Report Date: 06/22/22 Page 3 of 4
Permit: NCO024911 MRS Betweel 6 - 2018 and 6 - 2023 Region: % Violation Category:Limit Violation Program Category:
Facility Name:% Param Nam(% County: % Subbasin:% Violation Action:%
Major Minor: %
PERMIT: NCO024911 FACILITY: Metropolitan Sewerage District of Buncombe County COUNTY: Buncombe REGION: Asheville
North Carolina-French Broad River WRF
Limit Violation
MONITORING VIOLATION UNIT OF CALCULATED %
REPORT WELL LOCATION PARAMETER DATE FREQUENCY MEASURE LIMIT VALUE Over VIOLATION TYPE VIOLATION ACTION
06-2022 MW-6R/BIMS052233 Manganese,Total(as Mn) 06/30/22 3 X year ug/I 50 14,100 28,100 Limit Exceeded No Action, BPJ
10-2022 MW-6R/BIMS052233 Manganese,Total(as Mn) 10/31/22 3 X year ug/I 50 11,200 22,300 Limit Exceeded None
06-2019 MW-7/BIMS052232 Iron,Total(as Fe) 06/30/19 3 X year ug/I 300 1,730 476.7 Limit Exceeded No Action, BPJ
01-2020 MW-7/BIMS052232 Iron,Total(as Fe) 01/31/20 3 X year ug/I 300 627 109 Limit Exceeded No Action, BPJ
06-2020 MW-7/BIMS052232 Iron,Total(as Fe) 06/30/20 3 X year ug/I 300 447 49 Limit Exceeded No Action, BPJ
10-2020 MW-7/BIMS052232 Iron,Total(as Fe) 10/31/20 3 X year ug/I 300 831 177 Limit Exceeded No Action, BPJ
01-2021 MW-7/BIMS052232 Iron,Total(as Fe) 01/31/21 3 X year ug/I 300 334 11.3 Limit Exceeded No Action, BPJ
06-2019 MW-7/BIMS052232 Manganese,Total(as Mn) 06/30/19 3 X year ug/I 50 14,400 28,700 Limit Exceeded No Action, BPJ
01-2020 MW-7/BIMS052232 Manganese,Total(as Mn) 01/31/20 3 X year ug/I 50 125 150 Limit Exceeded No Action, BPJ
06-2020 MW-7/BIMS052232 Manganese,Total(as Mn) 06/30/20 3 X year ug/I 50 308 516 Limit Exceeded No Action, BPJ
06-2021 MW-7/BIMS052232 Manganese,Total(as Mn) 06/30/21 3 X year ug/I 50 176 252 Limit Exceeded No Action, BPJ
10-2021 MW-7/BIMS052232 Manganese,Total(as Mn) 10/31/21 3 X year ug/I 50 740 1,380 Limit Exceeded No Action, BPJ
06-2022 MW-7/BIMS052232 Manganese,Total(as Mn) 06/30/22 3 X year ug/I 50 191 282 Limit Exceeded No Action, BPJ
10-2022 MW-7/BIMS052232 Manganese,Total(as Mn) 10/31/22 3 X year ug/I 50 444 788 Limit Exceeded None
06-2019 MW-8R/BIMS052230 Iron,Total(as Fe) 06/30/19 3 X year ug/I 300 8,660 2,786.7 Limit Exceeded No Action, BPJ
10-2019 MW-8R/BIMS052230 Iron,Total(as Fe) 10/31/19 3 X year ug/I 300 2,860 853.3 Limit Exceeded No Action, BPJ
01-2020 MW-8R/BIMS052230 Iron,Total(as Fe) 01/31/20 3 X year ug/I 300 18,800 6,166.7 Limit Exceeded No Action, BPJ
06-2020 MW-8R/BIMS052230 Iron,Total(as Fe) 06/30/20 3 X year ug/I 300 70,700 23,466.7 Limit Exceeded No Action, BPJ
10-2020 MW-8R/BIMS052230 Iron,Total(as Fe) 10/31/20 3 X year ug/I 300 61,600 20,433.3 Limit Exceeded No Action, BPJ

MONITORING REPORT(MR)VIOLATIONS for: Report Date: 06/22/22 Page 4 of 4
Permit: NCO024911 MRS Betweel 6 - 2018 and 6 - 2023 Region: % Violation Category:Limit Violation Program Category:
Facility Name:% Param Nam(% County: % Subbasin:% Violation Action:%
Major Minor: %
PERMIT: NCO024911 FACILITY: Metropolitan Sewerage District of Buncombe County COUNTY: Buncombe REGION: Asheville
North Carolina-French Broad River WRF
Limit Violation
MONITORING VIOLATION UNIT OF CALCULATED %
REPORT WELL LOCATION PARAMETER DATE FREQUENCY MEASURE LIMIT VALUE Over VIOLATION TYPE VIOLATION ACTION
01-2021 MW-8R/BIMS052230 Iron,Total(as Fe) 01/31/21 3 X year ug/I 300 69,000 22,900 Limit Exceeded No Action, BPJ
06-2021 MW-8R/BIMS052230 Iron,Total(as Fe) 06/30/21 3 X year ug/I 300 50,700 16,800 Limit Exceeded No Action, BPJ
10-2021 MW-8R/BIMS052230 Iron,Total(as Fe) 10/31/21 3 X year ug/I 300 37,600 12,433.3 Limit Exceeded No Action, BPJ
01-2022 MW-8R/BIMS052230 Iron,Total(as Fe) 01/31/22 3 X year ug/I 300 32,300 10,666.7 Limit Exceeded No Action, BPJ
06-2022 MW-8R/BIMS052230 Iron,Total(as Fe) 06/30/22 3 X year ug/I 300 49,900 16,533.3 Limit Exceeded No Action, BPJ
10-2022 MW-8R/BIMS052230 Iron,Total(as Fe) 10/31/22 3 X year ug/I 300 18,400 6,033.3 Limit Exceeded None
06-2019 MW-8R/BIMS052230 Manganese,Total(as Mn) 06/30/19 3 X year ug/I 50 6,820 13,540 Limit Exceeded No Action, BPJ
10-2019 MW-8R/BIMS052230 Manganese,Total(as Mn) 10/31/19 3 X year ug/I 50 10,400 20,700 Limit Exceeded No Action, BPJ
01-2020 MW-8R/BIMS052230 Manganese,Total(as Mn) 01/31/20 3 X year ug/I 50 11,700 23,300 Limit Exceeded No Action, BPJ
06-2020 MW-8R/BIMS052230 Manganese,Total(as Mn) 06/30/20 3 X year ug/I 50 19,700 39,300 Limit Exceeded No Action, BPJ
10-2020 MW-8R/BIMS052230 Manganese,Total(as Mn) 10/31/20 3 X year ug/I 50 14,800 29,500 Limit Exceeded No Action, BPJ
01-2021 MW-8R/BIMS052230 Manganese,Total(as Mn) 01/31/21 3 X year ug/I 50 20,100 40,100 Limit Exceeded No Action, BPJ
06-2021 MW-8R/BIMS052230 Manganese,Total(as Mn) 06/30/21 3 X year ug/I 50 15,000 29,900 Limit Exceeded No Action, BPJ
10-2021 MW-8R/BIMS052230 Manganese,Total(as Mn) 10/31/21 3 X year ug/I 50 11,000 21,900 Limit Exceeded No Action, BPJ
01-2022 MW-8R/BIMS052230 Manganese,Total(as Mn) 01/31/22 3 X year ug/I 50 9,780 19,460 Limit Exceeded No Action, BPJ
06-2022 MW-8R/BIMS052230 Manganese,Total(as Mn) 06/30/22 3 X year ug/I 50 17,000 33,900 Limit Exceeded No Action, BPJ
10-2022 MW-8R/BIMS052230 Manganese,Total(as Mn) 10/31/22 3 X year ug/I 50 8,850 17,600 Limit Exceeded None

United States Environmental Protection Agency Form Approved.
EPA Washington,D.C.20460 OMB No.2040-0057
Water Compliance Inspection Report 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 IN 2 u 3 I NCO024911 111 121 23/02/23 I17 18 I D I 19 I G I 20U
21111I I I I I I I II I I I I I I I I I I I I I I I I I I I I I I I II I I I I I r6
Inspection Work Days Facility Self-Monitoring Evaluation Rating B1 QA ----------------------Reserved-------------------
67 70 J 71 Ity 72 L-J 73 1 74 79 I I I I 80
Section B: Facility Data
Name and Location of Facility Inspected(For Industrial Users discharging to POTW,also include Entry Time/Date Permit Effective Date
POTW name and NPDES permit Number) 08:30AM 23/02/23 18/10/01
French Broad River WRF
NC Hwy 251 Exit Time/Date Permit Expiration Date
Asheville NC 28814 01:OOPM 23/02/23 22/12/31
Name(s)of Onsite Representative(s)/Titles(s)/Phone and Fax Number(s) Other Facility Data
Bart T Farmer/ORC/828-225-8224/
Name,Address of Responsible Official/Title/Phone and Fax Number
Contacted
Thomas E Hartye,2028 Riverside Dr Asheville NC 288043054/General
Manager/828-225-8399/ No
Section C:Areas Evaluated During Inspection (Check only those areas evaluated)
Pretreatment
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
Timothy H Heim DWR/ARO WQ/828-296-4665/
Signature of Management Q A Reviewer Agency/Office/Phone and Fax Numbers Date
EPA Form 3560-3(Rev 9-94)Previous editions are obsolete.
Page#

NPDES yr/mo/day Inspection Type (Cont.) 1
31 NCO024911 I11 12I 23/02/23 117 18 1 o
Section D: Summary of Finding/Comments (Attach additional sheets of narrative and checklists as necessary)
Tim Heim of the Asheville Regional Office performed a Pretreatment Compliance Inspection (PCI) on
February 21st & 23rd, 2023. Chad Ledford (MSD Pretreatment), and Leslie Frady (Milkco EH&S)
assisted with the inspection and with records and sampling results review.
The pretreatment program, associated record keeping, and the relationship with the IUs were in good
order at the time of the inspection and compliant with permit conditions.
DEQ ARO staff observed pretreatment inspection and sampling of an Industrial User: (IU) in the
program, Milkco Inc. (IUP# S-036).
See attached NC DEQ Pretreatment Compliance Inspection form for details.
Page# 2

Permit: NC0024911 Owner-Facility: French Broad River WRF
Inspection Date: 02/23/2023 Inspection Type: Pretreatment Compliance
Yes No NA NE
Page# 3

United States Environmental Protection Agency Form Approved.
EPA Washington,D.C.20460 OMB No.2040-0057
Water Compliance Inspection Report 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 IN 1 2 u 3 I NCO024911 111 121 22/04/14 I17 18 LC]I 19 I G I 20U
21111I I I I I I I II I I I I I I I I I I I I I I I I I I I I I I I II I I I I I r6
Inspection Work Days Facility Self-Monitoring Evaluation Rating B1 QA ----------------------Reserved-------------------
67 70 J 71 Ity 72 L-J 73 1 74 79 I I I I 80
Section B: Facility Data
Name and Location of Facility Inspected(For Industrial Users discharging to POTW,also include Entry Time/Date Permit Effective Date
POTW name and NPDES permit Number) 02:OOPM 22/04/14 18/10/01
French Broad River WRF
NC Hwy 251 Exit Time/Date Permit Expiration Date
Asheville NC 28814 04:30PM 22/04/14 22/12/31
Name(s)of Onsite Representative(s)/Titles(s)/Phone and Fax Number(s) Other Facility Data
Roger C Edwards/ORC/828-225-8224/
Name,Address of Responsible Official/Title/Phone and Fax Number
Contacted
Thomas E Hartye,2028 Riverside Dr Asheville NC 288043054/General
Manager/828-225-8399/ No
Section C:Areas Evaluated During Inspection (Check only those areas evaluated)
Permit 0 Operations&Maintenar 0 Records/Reports Self-Monitoring Progran
Facility Site Review
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
Timothy H Heim DWR/ARO WQ/828-296-4665/
Signature of Management Q A Reviewer Agency/Office/Phone and Fax Numbers Date
EPA Form 3560-3(Rev 9-94)Previous editions are obsolete.
Page#

NPDES yr/mo/day Inspection Type (Cont.) 1
31 NCO024911 I11 12I 22/04/14 117 18 i c i
Section D: Summary of Finding/Comments (Attach additional sheets of narrative and checklists as necessary)
Tim Heim of the Asheville Regional Office performed a Compliance Inspection of the Facility on April
14, 2022. Roger Edwards (ORC)was present and assisted with the inspection. The facility appeared
well operated at the time of the inspection, and in compliance with Permit NC0024911.
The following additional items were noted at the time of the inspection:
The new high rate primary clarifier is operational and undergoing startup commissioning
The facility is evaluating future upgrades to biological treatment and other components. Consider
discussions with ARO regarding maintaining compliance during construction of these upgrades.
Page# 2

Permit: NCO024911 Owner-Facility: French Broad River WRF
Inspection Date: 04/14/2022 Inspection Type: Compliance Evaluation
Operations & Maintenance Yes No NA NE
Is the plant generally clean with acceptable housekeeping? 0 ❑ ❑ ❑
Does the facility analyze process control parameters, for ex: MLSS, MCRT, Settleable ❑ ❑ ❑
Solids, pH, DO, Sludge Judge, and other that are applicable?
Comment:
Permit Yes No NA NE
(If the present permit expires in 6 months or less). Has the permittee submitted a new ❑ ❑ 0 ❑
application?
Is the facility as described in the permit? 0 ❑ ❑ ❑
#Are there any special conditions for the permit? ❑ ■ ❑ ❑
Is access to the plant site restricted to the general public? 0 ❑ ❑ ❑
Is the inspector granted access to all areas for inspection? 0 ❑ ❑ ❑
Comment:
Pump Station - Influent Yes No NA NE
Is the pump wet well free of bypass lines or structures? 0 ❑ ❑ ❑
Is the wet well free of excessive grease? 0 ❑ ❑ ❑
Are all pumps present? 0 ❑ ❑ ❑
Are all pumps operable? 0 ❑ ❑ ❑
Are float controls operable? 0 ❑ ❑ ❑
Is SCADA telemetry available and operational? 0 ❑ ❑ ❑
Is audible and visual alarm available and operational? M ❑ ❑ ❑
Comment:
Bar Screens Yes No NA NE
Type of bar screen
a.Manual ❑
b.Mechanical
Are the bars adequately screening debris? 0 ❑ ❑ ❑
Is the screen free of excessive debris? ■ ❑ ❑ ❑
Is disposal of screening in compliance? 0 ❑ ❑ ❑
Is the unit in good condition? 0 ❑ ❑ ❑
Comment:
Page# 3

Permit: NC0024911 Owner-Facility: French Broad River WRF
Inspection Date: 04/14/2022 Inspection Type: Compliance Evaluation
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? 0 ❑ ❑ ❑
# Is disposal of grit in compliance? 0 ❑ ❑ ❑
Comment:
Primary Clarifier Yes No NA NE
Is the clarifier free of black and odorous wastewater? 0 ❑ ❑ ❑
Is the site free of excessive buildup of solids in center well of circular clarifier? ❑ ❑ 0 ❑
Are weirs level? 0 ❑ ❑ ❑
Is the site free of weir blockage? 0 ❑ ❑ ❑
Is the site free of evidence of short-circuiting? 0 ❑ ❑ ❑
Is scum removal adequate? 0 ❑ ❑ ❑
Is the site free of excessive floating sludge? ■ ❑ ❑ ❑
Is the drive unit operational? ❑ ❑ 0 ❑
Is the sludge blanket level acceptable? ❑ ❑ 0 ❑
Is the sludge blanket level acceptable? (Approximately '/4 of the sidewall depth) ❑ ❑ 0 ❑
Comment: Rapid ActiFlow settling type primary clarifier.
Rotating Biological Contactor Yes No NA NE
Is the unit free of excessive sloughing of growth? 0 ❑ ❑ ❑
Is the unit operational? 0 ❑ ❑ ❑
Are media panels in good condition? 0 ❑ ❑ ❑
Comment:
Secondary Clarifier Yes No NA NE
Is the clarifier free of black and odorous wastewater? 0 ❑ ❑ ❑
Is the site free of excessive buildup of solids in center well of circular clarifier? ❑ ❑ 0 ❑
Are weirs level? 0 ❑ ❑ ❑
Is the site free of weir blockage? ■ ❑ ❑ ❑
Is the site free of evidence of short-circuiting? M ❑ ❑ ❑
Page# 4

Permit: NC0024911 Owner-Facility: French Broad River WRF
Inspection Date: 04/14/2022 Inspection Type: Compliance Evaluation
Secondary Clarifier Yes No NA NE
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 '/4 of the sidewall depth) ■ ❑ ❑ ❑
Comment: Rectangular clarifiers.
Filtration (High Rate Tertiary) Yes No NA NE
Type of operation: Cross 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? ■ ❑ ❑ ❑
Comment: Textile base disk filters.
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? ❑ ❑ ❑ ■
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? ■ ❑ ❑ ❑
Page# 5

Permit: NC0024911 Owner-Facility: French Broad River WRF
Inspection Date: 04/14/2022 Inspection Type: Compliance Evaluation
De-chlorination Yes No NA NE
Comment:
Are the tablets the proper size and type? ❑ ❑ ■ ❑
Are tablet de-chlorinators operational? ❑ ❑ ■ ❑
Number of tubes in use?
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? ■ ❑ ❑ ❑
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? ■ ❑ ❑ ❑
Comment:
Page# 6

Whole Effluent Toxicity Testing and Self Monitoring Summary
Buncombe County MSD NCO024911/001 County: Buncombe Region: ARO Basin: FRB02 Feb May Aug Nov SOC JOC:
Ceri7dPF Begin: 10/1/2018 chr lim:12% NonComp: Single 7Q10: 466.0 PF: 40.0 IWC: 12.0 Freq: Q
J F M A M J J A S O N D
2019 - Pass - - >48(P) - - Pass - - Pass -
2020 - Pass - - Pass - - >48(P) - - Pass -
2021 - Pass - - Pass - - Pass - - Pass>48(P) -
2022 - Pass - - Pass 33.9(P) - - Pass - - Pass -
2023 - Pass Pass - - - - - - - - - -
Bunn WWTP NCO042269/001 County: Franklin Region: RRO Basin: TAR01 Mar Jun Sep Dec SOC JOC:
Ceri7dPF Begin: 8/1/2020 chr lim:11%@ 0.15 NonComp: Single 7Q10: 1.8 PF: 0.15 IWC: 11 Freq: Q
J F M A M J J A S O N D
2019 - - Pass - - Pass - - Pass - - Pass
2020 - - Pass - - Pass - - Pass - - Pass
2021 - - Pass - - Pass - - Pass - - Pass
2022 - - Pass - - Pass - - Pass - - Pass
2023 - - Pass - - - - - - - - -
Burlington East WWTP NCO023868/001 County: Alamance Region: WSRO Basin: CPF02 Feb May Aug Nov SOC JOC:
Ceri7dPF Begin: 7/1/2014 chr lim:36% NonComp: SINGLE 7Q10: 33.6 PF: 12.0 IWC: 36 Freq: Q
J F M A M I J A S O N D
2019 - Pass - - Pass - - Pass - - Pass -
2020 - Pass - - Pass - - Pass - - Pass -
2021 - Pass - - Pass - - Pass - - Pass -
2022 - Pass - - Pass - - Pass - - Pass -
2023 - Pass - - - - - - - - - -
Burlington Industries WWTP NCO043320/001 County: Richmond Region: FRO Basin: YAD16 Feb May Aug Nov SOC JOC:
Ceri7dPF Begin: 6/1/2015 chr lim:7% NonComp: Single 7Q10: 25.0 PF: 1.2 IWC: 7.0 Freq: Q
J F M A M J J A S O N D
2019 - Pass - - Pass - - Pass - - Pass -
2020 - Pass - - Pass - - Pass - - Pass -
2021 - Pass - - Pass - - Pass - - Pass -
2022 - Pass - - Pass - - Pass - - Pass -
2023 - Pass - - - - - - - - - -
Burlington-South WWTP NCO023876/001 County: Alamance Region: WSRO Basin: CPF02 Jan Apr Jul Oct SOC JOC:
Ceri7dPF Begin: 7/1/2014 chr lim:86% NonComp: Single 7Q10: 3.0 PF: 12.0 IWC: 86 Freq: Q
J F M A M J I A S O N D
2019 Pass - - Pass - - Pass - - Pass - -
2020 Pass - - Pass - - Pass - - Pass - -
2021 Pass - - Pass - - Pass - - Pass - -
2022 Pass - - Pass - - Pass - - Pass - -
2023 Pass - - Pass - - - - - - - -
Leeend: P=Fathead minnow(PimDhales oromelas).H=No Flow(facility is active).s=SDlit test between Certified Labs Page 13 of 115

A B C D E F G H I J K L M N O P
1
Pollutants of Concern (POC) Review Form Version: 2022.09.28
2 1. Facility's General Information
3 Date of(draft) Review 6/22/2023 c. POC review due to: e. Contact Information
4
Date of(final) Review 3/7/2024 Municipal NPDES renewal 0 Regional Office(RO) Asheville
5 NPDES Permit Writer(pw) Nick Coco HWA-AT/LTMP Review ❑ RO PT Staff Daniel Boss RO NPDES Staff Daniel Boss
6
Perm ittee-Facility Name French Broad River WRF New Industries ❑ Facility PT Staff, email Shannon Bergeron, sbergeron(a)msdbc.org
7 NPDES Permit Number NCO024911 WWTP expansion ❑ f. Receiving Stream
8 NPDES Permit Effective Date 5/1/2024 Stream reclass./adjustment ❑ Outfall
Chemical Addendum Submittal 6/14/2022 Outfall relocation/adjustment ❑ Receiving Stream: French Broad QA, cfs: 2140
9 Date River
10 NPDES Permit Public Notice Date 1/28/2024 7Q10 update ❑ Stream Class B 7Q10 (S), cfs: 466
11
eDMR data evaluated from: 5/1/2019 to 5/30/2023 Other POC review trigger, explain: Oufall Lat. 35.39.02 Outfall Long. 82.35.54
12 a. WWTP Capacity Summary Outfall II
Current Permitted Flow, mgd 40.0 Designed Flow, An „ Receiving Stream: QA, cfs:
13 mgd
14 Permitted SIU Flow, mgd 0.8769 d. IU Summary Stream Class 7Q10, cfs:
15 b. PT Docs. Summary #IUs Oufall Lat. Outfall Long.
16
IWS approval date 4/2/2020 #SIUs Is there a PWS intake downstream of the Facility's Outfall(s)? [0 YES ❑ NO
17
L/STMP approval date: 10/21/2019 #CIUs Comments:
18 #NSCIUs
HWA-AT approval date 7/10/2019 #IUs w/Local 19 Discharge is approximatley 10 miles upstream of Tennessee state line
Permits or Other
19 ITypes
20 2. Industrial Users' Information.
21 # Industrial User(IU) Name IU Activity IU Non Conventional Pollutans &Toxic Pollutant IUP Effective Date
22 1 Arcadia Farms SIC 2086 flow, pH, tiUU, 15S 1/1/2022
23 2 Asheville Metal SIC 3471 flow, pH, cadmium, chromium, copper, lead, nickel, silver, zinc, tin, total metals, cyanide,TTO 1/1/2022
3 Asheville Paint&Powder SIC 3477 flow, pH, cadmium, chromium, copper, lead, nickel, silver, zinc, cyanide, TTO 1/1/2022
24
25 4 Blue Ridge Metals SIC 3452, 3315 flow, pH, lead, zinc 1/1/2022
5 Clement Pappas NC, LLC SIC 2033 flow, pH, BOD, TSS 9/1/2022
26
6 Continental SIC 3714 flow, pH, cadmium, chromium, copper, lead, nickel, silver, zinc, cyanide, TTO 1/1/2022
27
a- 7 Craggy Prison Laundry SIC 7218 flow, pH, BOD, TSS 1/1/2022
28 W
a- 8 Day International NAICS 326299, flow, pH, TSS, O&G, BOD, MEK, Toluene, TSS 1/1/2022
Z 326150, 326199
29
9 Glatfelter SIC 2297 flow, pH, BOD, TSS 8/1/2022
30
10 Industry Nine SIC 3471 flow, pH, cadmium, chromium, copper, lead, nickel, silver, zinc, cyanide, TTO 1/1/2022
31
11 Kearfott SIC 3769 flow, pH, cadmium, chromium, copper, lead, nickel, silver, zinc, cyanide, TTO 1/1/2022
32
12 Linamar Light Metals SIC 3363 flow, pH, chromium, copper, lead, nickel, zinc, cyanide, total phenols, O&G, TTO 7/1/2022
33
13 Meritor NAICS 336399 flow, pH, cadmium, chromium, copper, lead, nickel, silver, zinc, cyanide, TTO 1/1/2022
34
14 Milkco SIC 2026, 2037, flow, pH, BOD, TSS 1/1/2022
35 3085
15 Mission SIC 7213 flow, pH, BOD, TSS, COD 1/1/2022
36
16 New Belgium NAICS 312120 flow, pH, BOD, TSS 1/1/2022
37
17 rrince Manufacturing SIC 3479, 3469, flow, pH, cadmium, chromium, copper, lead, nickel, silver, zinc, cyanide, TTO 12/1/2022
38 3471
18 Samoa SIC 3561 flow, pH, cadmium, chromium, copper, lead, nickel, silver, zinc, cyanide, TTO 1/1/2022
39
19 Sierra Nevada NAICS 312120 flow, pH, BOD, TSS 1/1/2022
40
20 Williams Plating SIC 3471 flow, pH, cadmium, chromium, copper, lead, nickel, silver, zinc, tin, cyanide, BOD, TTO 1/1/2022
41
Comment:
46
47 3. Status of Pretreatment Program (check all that apply)
48 Status of Pretreatment Program (check all that apply)
49 ❑ 1) facility has no SIUs, does have Division approved Pretreatment Program that is INACTIVE
50 ❑ 2) facility has no SIUs, does not have Division approved Pretreatment Program
-------------------------------------------------------- -----------
51 ❑ 3) facility has SIUs and DWQ approved Pretreatment Program
52 0 3a) Full Program with LTMP
53 ❑ 3b) Modified Program with STMP
54 ❑ 4) additional conditions regarding Pretreatment attached or listed below
55 ❑ 5) facility's sludge is being land applied or composted
56 JE
6) facility's sludge is incinerated (add Beryllium and Mercury sampling according to §503.43)
57 7) facility's sludge is taken to a landfill, if yes which landfill:
58 8) other
59 Sludge Disposal Plan: sludge is dewatered and incinerated
60
61
62 Sludge Permit No:
Page 1 POC Review Form

A B C D E F G H I I J I K I L M N O P
63 4. LTMP/STMP and HWA Review
64 PW: Find L/STMP document, HWA spreadsheet, DMR, previous and new NPDES permit for next section.
a Parameter of New Previous Required by POC due to POC due to POTW % L/STMP NPDES Comment
Concern (POC) NPDES NPDES EPA PT(1) Sludge (2) SIU (3) POC (4) Removal Effluent Freq. Effluent Freq.
Check List POC POC Rate PQLs review
c
65 U
a- PQL from Required PQL Recomm.
L/STMP, ug/I per NPDES PQL, ug/I
66 permit
67 Flow El 0 0 Elcontinuous
68 ❑ BOD Ll ❑ ❑ ❑ 2/week
69 ❑ CBOD p ❑
70 TSS ❑ ❑� Q 2/week
71 0 NH3 ❑ 0 0 ❑ Q 2/week
72 ❑ Arsenic ❑ ❑ 0 0 ❑ Q
73 ❑ Barium ❑ ❑ ❑ ❑ ❑ Q
74 ❑ Beryllium(5) ❑ ❑ ❑ ❑ ❑ Q
75 p Cadmium(1) ❑ ❑ p 0 0 ❑ Q 0.5
76 p Chromium(1) ❑ ❑ 0 0 p ❑ Q 5.0
77 [2] Copper(l) ❑ ❑ ❑ ❑ El ❑ Q 2.0
78 p Cyanide ❑ ❑ p p ❑ Q
79 0 Lead(1) ❑ ❑ 0 0 p ❑ Q 2.0
80 ❑ Mercury(5) ❑ ❑ p p ❑ Q 0.001
81 ❑ Molybdenum ❑ ❑ ❑ ❑ ❑ Q 10.0
82 p Nickel(1) ❑ ❑ p p p ❑ Q
83 m Selenium ❑ ❑ 0 p ❑ Q 1.0
84 r,� Silver ❑ ❑ 0 0 ❑ Q 1.0
85 0 Zinc(1) ❑ ❑ 0 121 0 ❑ Q 10.0
86 p Sludge Flow to Disposal p ❑ ❑ Q
87 p % Solids to Disposal ❑ ❑ Q
88 Tin 0 0 ❑ Q
89 0 Total Phenols ❑ ❑ 0 ❑
90 ❑ ❑ ❑ ❑ ❑
91 ❑ ❑ ❑ ❑ ❑
92 ❑ ❑ ❑ ❑ ❑
93 ❑ ❑ ❑ ❑ ❑
94 ❑ ❑ ❑ ❑ ❑
95 ❑ ❑ ❑ ❑ ❑
96 ❑ ❑ ❑ ❑ ❑
97 ❑ ❑ ❑ ❑ ❑
98 Footnotes:
99 (1)Always in the LTMP/STMP due to EPA-PT requirement
100 (2)Only in LTMP/STMP if listed in sludge permit
101 (3)Only in LTMP/STMP while SIU still discharges to POTW
102 (4)Only in LTMP/STMP when pollutant is of concern to POTW
103 (5) In LTMP/STMP, if sewage sludge is incinerated
104 Please use blue font for the info updated by pw
105 Please use red font for POC that need to be added/modified in USTMP sampling plan
106 Please use orange font and strikethrough for POC that may be removed from USTMP POC listis
107 Blue shaded cell (D60:1-181): Parameters usually included under that POC list
Vi
108 W
5. Comments
Facility Summary/background information/NPDES-PT regulatory action:
POC to be added/modified in L/STMP:
109
110 ORC's comments on IU/POC: PrPOC submitted through Chemical
Addendum or Supplemental Chemical
111 Datasheet:
Additional pollutants added to USTMP due
112 to POTW s concerns:
113 NPDES pw's comments on IU/POC:
114 6. Pretreatment updates in response to NPDES permit renewal
115 NPDES Permit Effective Date 5/1/2024 180 days after effective(date): 110/28/20241 Permit writer, please add list of required/recommended PT updates in NPDES permit cover letter.
Page 2 POC Review Form