NC0025071_Fact Sheet_20210412

Fact Sheet
NPDES Permit No. NC0025071
Permit Writer/Email Contact: Cassidy Kurtz, [e-mail]
Date: April 12, 2021
Division/Branch: NC Division of Water Resources/NPDES Municipal Permitting
Fact Sheet Template: Version 09Jan2017
Permitting Action:
❑X 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:
City of Eden / Mebane Bridge WWTP
Applicant Address:
PO Box 70, Eden, NC 27289
Facility Address:
204 Mebane Bridge Rd., Eden, NC 27288
Permitted Flow:
13.5 MGD
Facility Type/Waste:
MAJOR Municipal
Facility Class:
Class IV
Treatment Units:
Bar Screens, Grit Separator, Aeration Basins, Secondary Clarifiers,
Chlorination + Dechlorination, CleanB treatment system, Sludge
Lagoon, Belt Press
Pretreatment Program (Y/N):
Yes
County:
Rockingham
Region:
Winston Salem
Briefly describe the proposed permitting action and facility background:
City of Eden has applied for an NPDES permit renewal at 13.5 MGD at the Mebane Bridge WWTP. This
facility serves a population of approximately 18,250 residents within Eden and Wentworth. This facility
maintains a full pretreatment program with 3 Significant Industrial Users, 2 of which are Categorical
Page 1 of 11

Industrial Users — Karastan Rug Mill (packaged rugs and broadloom carpets), Duke Energy Dan River
Combined Cycle Station (leachate from coal ash landfills), and Weil McLain (residential and commercial
boilers, sheet metal forming, finishing and assembly).
The City applied for an Authorization to Construct (AtC) permit in September 2018, which was issued
December 2018. This AtC permit includes replacing existing RAS and WAS pumps at pump stations 1
and 2 with new RAS and WAS pumps, installing a new sludge chemical stabilization unit (Clean B unit),
installing a new steel sludge storage tank, constructing a new sludge transfer pump station (with 2 sludge
transfer pumps), installing a new sludge transfer forcemain, constructing a new chemical storage shed,
and installing 2 new magnetic flow meters. The signed Engineer's Certificate will be returned to DWR
once these modifications have been completed.
Additionally, with this permit renewal, the City requests a reduction in monitoring frequency for BOD,
TSS, Fecal Coliform, and NH3-N, based on the exceptionally performing facilities criteria. Facility
effluent data for these parameters was reviewed from October 2015 to October 2018, and the facility was
granted this request. See Section 10. Monitoring Requirements.
2. Receiving Waterbody Information
Receiving Waterbody Information
Outfalls/Receiving Stream(s):
Outfall 001 — Dan River
Stream Segment:
22-(39)a *
Stream Classification:
C *
Drainage Area (mi2):
1701
Summer 7Q10 (cfs):
370 (July 1994) *
Winter 7Q10 (cfs):
600 (July 1994) *
30Q2 (cfs):
740 (July 1994) *
Average Flow (cfs):
1621 *
IWC (% effluent):
5.35% at 13.5 MGD
303(d) listed/parameter:
No, the segment is not listed on the 2018 303(d) list
Subject to TMDL/parameter:
Yes- State wide Mercury TMDL implementation.
Sub-basin/HUC:
Outfall 001: 03-02-03 / HUC: 03010103
USGS Topo Quad:
B20NW — Southeast Eden, NC
*The previous permit listed the outfall location incorrectly; this was verified in the application for this
renewal. The outfall latitude has been corrected to 36.28.17; longitude was correct as 79.44.35. The
previously listed outfall latitude was 36.25.17, which caused the following stream information to be
incorrect (previous information listed in parenthesis): stream segment (22-(31.5)), stream classification
(WS-IV), summer 7Q10 (386 cfs), winter 7Q10 (594 cfs), 30Q2 (none listed), average flow (1920 cfs).
Page 2 of 11

3. Effluent Data Summary
Effluent data for Outfall 001 is summarized below for the period of January 2016 through May 2020.
Table 1. Effluent Data Summary Outfall 001
Parameter
Units
Average
Max
Min
Permit
Limit
Flow
MGD
3.893
27.725
1.705
MA 13.5
BOD
mg/1
4.23
31.6
< 2
WA 45.0
MA 30.0
TSS
mg/1
6.17
139
2.25
WA 45.0
MA 30.0
NH3N summer
mg/1
0.13
2.9
< 0.01
WA 35.0
MA 14.8
NH3N winter
mg/1
0.36
5.3
< 0.1
pH
SU
6.84
7.47
6.18
6.0 < pH <
9.0
Fecal coliform
#/100 ml
10.48
> 2419.6
< 1
(geometric)
WA 400
MA 200
TRC
µg/1
10.04
27.9
< 10
DM 28.0
(< 50
compliance)
Temperature
° C
17.8
27.9
6.2
DO
mg/1
8.66
14.62
5.25
Mercury
ng/1
2.66
4.82
1.12
Total Copper
µg/1
57.1
690
8.4
TN
mg/1
10.6
15.7
3.3
TP
mg/1
0.158
0.33
0.072
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).
Page 3 of 11

If applicable, summarize any instream data and what instream monitoring will be proposed for this
permit action:
The current permit requires instream monitoring for temperature, conductivity, dissolved oxygen and pH.
This permit maintains the same instream monitoring requirements, with the addition of quarterly upstream
hardness sampling. The table below summarizes instream data from January 2016 to May 2020.
Table 2. Instream Data Summary
Parameter
Upstream
Downstream
Avg
Max
Min
Avg
Max
Min
Temperature
(° C)
18.0
27.8
0.2
18.3
28.5
0
Conductivity
(umhos/cm)
84.9
239
26.2
86.4
233
26.1
Dissolved
Oxygen
(mg/1)
8.79
16.73
5.86
8.83
16.85
5.75
pH (su)
7.4
9.16
5.42
7.15
8.26
5.77
Review of this data included analysis using Students T-test at a 95% confidence interval, where a p value
<0.05 signifies a statistically significant difference between the upstream and downstream locations.
Analysis indicates that:
1. Temperature standard of 2.8°C increase was maintained, and there was not a statistically
significant increase from upstream to downstream sampling sites.
2. Conductivity did not significantly increase from upstream to downstream sampling sites.
3. DO did not significantly increase from upstream to downstream sampling sites.
4. pH slightly decreased from upstream to downstream; this decrease is statistically significant.
[Over the period of analysis (January 2016 through October 2018), there were 4 occasions where
the downstream pH dropped below 6.0 s.u. On one of these days (4/23/2018), the upstream pH
was 5.47 and the effluent (6.94 s.u.) appeared to increase the receiving stream's pH to 5.98 at the
downstream location.
Is this facility a member of a Monitoring Coalition with waived instream monitoring (Y/N): NO
Name of Monitoring Coalition: NA
5. Compliance Summary
Summarize the compliance record with permit effluent limits (past 5 years): The facility reported no limit
violations from January 2016 to June 2020.
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 March 2016 through June 2020.
Summarize the results from the most recent compliance inspection: The last routine compliance
inspection was conducted in September 2019. The inspector noted the facility as noncompliant due to the
following issues:
• Flow proportional sampling - The facility should set up the system for proper flow proportional
sampling.
Page 4 of 11

• Record Keeping — Analytical results inconsistent with data reported on DMRs; "Reviewed the
DMR for 9/18/2019 and noted that Effluent Zinc was reported as kg/day, and not mg/1. No
conversion was made, thus this is simply a unit error. The DMRs with this fault should be
corrected and resubmitted. This appears to have been present in DMRs since 6/2016."
• Effluent Pipe - "The outfall was not observed due to access issues. The operators said that they
tried to get the lines crew to clear the outfall ROW but due to the time of year it was not directly
accessible."
• Flow Measurement -Effluent - "Flow meters are installed on the effluent sides of the 3 chlorine
contact chambers and they are calibrated but not connected to SCADA and not used for flow
reporting or flow proportioning."
6. Water Quality -Based Effluent Limitations (WQBELs)
Dilution and Mixing Zones
In accordance with 15A NCAC 2B.0206, the following streamflows are used for dilution considerations
for development of WQBELs: 1 Q 10 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: Limitations for
BOD are based on secondary treatment standards, and there is no DO limit in the permit. No changes are
proposed from the previous permit limits.
Ammonia and Total Residual Chlorine Limitations
Limitations for ammonia are based on protection of aquatic life utilizing an ammonia chronic criterion of
1.0 mg/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: Summer
ammonia limits of 14.8 mg/L (monthly average limit) and 35.0 mg/L (weekly average limit) have been in
the permit since 2008 and are based on waste load allocation (WLA) calculations to protect for ammonia
toxicity. No winter limits have been required. There are no proposed changes as these limits are supported
by current WLA calculations.
TRC limits were added to the permit in 1990 and are based on waste load allocation calculations for
expansion to 13.5 MGD (current permitted flow). These limits are still supported by current WLA
calculations.
Page 5 of 11

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/z 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 March 2016
and March 2020. Pollutants of concern included toxicants with positive detections and associated water
quality standards/criteria. Based on this analysis, the following permitting actions are proposed for this
permit:
• Effluent Limit with Monitoring. The following parameters will receive a water quality -based
effluent limit (WQBEL) since they demonstrated a reasonable potential to exceed applicable
water quality standards/criteria: None
• Monitoring Only. The following parameters will receive a monitor -only requirement since they
did not demonstrate reasonable potential to exceed applicable water quality standards/criteria,
but the maximum predicted concentration was >50% of the allowable concentration: Copper,
Silver
Copper — One sample (3/8/2016) was 690 ug/L. All other samples were <50% of the
facility's allowable discharge concentration (159.09 ug/L). BPJ.
Silver — All samples reported <5 ug/L. Permittee shall sample to the lowest PQL (1.0
ug/L) to show that they can meet the allowable discharge concentration (1.2 ug/L).
*Note: Both copper and silver are already being monitored quarterly through the facility's
pretreatment program.
• 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: Arsenic, Beryllium, Cadmium, Total Phenolic Compounds, Total Chromium,
Cyanide, Lead, Molybdenum, Nickel, Selenium, 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: NA
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: NA
Attached are the RPA results as well as a copy of the guidance entitled `NPDES Implementation of
Instream Dissolved Metals Standards — Freshwater Standards."
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
Page 6 of 11

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 5.4%
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/1
Table 3. Mercury Effluent Data Summary
2016
2017
2018
2019
2020
# of Samples
4
4
4
4
1
Annual Average Conc. ng/L
1.9
2.8
2.4
3.2
3.8
Maximum Conc., ng/L
2.76
3.64
3.18
4.82
3.79
TBEL, ng/L
47
WQBEL, ng/L
233.36
Describe proposed permit actions based on mercury evaluation: Effluent mercury data was reviewed
from March 2016 to March 2020. Because no annual average mercury concentration exceeded the
WQBEL and no individual sample exceeded the TBEL, a mercury limit has not been added to the permit.
However, since the facility is > 2 MGD and reported quantifiable levels of mercury (>1 ng/1), a mercury
minimization plan (MMP) has been added to the permit. Annual mercury monitoring has been removed
from the permit, however, the permittee must continue to sample for mercury with the Effluent Pollutant
Scans using EPA method 1631 E.
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: NA
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
1 SA NCAC 2H. 0107(c) (2) (B), 40CFR 122.47, and EPA May 2007 Memo: NA
Page 7 of 11

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/1
BOD5/TSS for Monthly Average, and 45 mg/1 for BOD5/TSS for Weekly Average). YES
If NO, provide a justification for alternative limitations (e.g., waste stabilization pond). NA
Are 85% removal requirements for BOD5/TSS 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
9. Antibacksliding Review
Sections 402(o)(2) and 303(d)(4) of the CWA and federal regulations at 40 CFR 122.44(1) prohibit
backsliding of effluent limitations in NPDES permits. These provisions require effluent limitations in a
reissued permit to be as stringent as those in the previous permit, with some exceptions where limitations
may be relaxed (e.g., based on new information, increases in production may warrant less stringent TBEL
limits, or WQBELs may be less stringent based on updated RPA or dilution).
Are any effluent limitations less stringent than previous permit (YES/NO): NO
If YES, confirm that antibacksliding provisions are not violated: NA
10. Monitoring Requirements
Monitoring frequencies for NPDES permitting are established in accordance with the following
regulations and guidance: 1) State Regulation for Surface Water Monitoring, 15A NCAC 2B.0500; 2)
NPDES Guidance, Monitoring Frequency for Toxic Substances (7/15/2010 Memo); 3) NPDES Guidance,
Reduced Monitoring Frequencies for Facilities with Superior Compliance (10/22/2012 Memo); 4) Best
Professional Judgement (BPJ). Per US EPA (Interim Guidance, 1996), monitoring requirements are not
considered effluent limitations under Section 402(o) of the Clean Water Act, and therefore anti -
backsliding prohibitions would not be triggered by reductions in monitoring frequencies.
For instream monitoring, refer to Section 4.
With this permit renewal, the City requested to reduce monitoring frequency of BOD, TSS, Fecal
Coliform, and NH3-N from daily to 2/week. Data was reviewed from May 2017 through May 2020 and
Page 8 of 11

compared against the criteria established in the "DWQ Guidance Regarding the Reduction of Monitoring
Frequencies in NPDES Permits for Exceptionally Performing Facilities". The data justifies reduced
monitoring for these parameters, so this request was granted. The "Data Summary for Reduced NPDES
Permit Monitoring Frequency" is attached to this fact sheet.
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.
12. Summary of Proposed Permitting Actions
Table 4. Current Permit Conditions and Proposed Changes 13.5 MGD
Parameter
Current Permit
Proposed Change
Basis for Condition/Change
Flow
MA 13.5 MGD
No change
15A NCAC 2B .0505
BOD5
MA 30.0 mg/1
WA 45.0 mg/1
No change to limits
Decreased monitoring
frequency: 2x/week
WQBEL. Based on protection of DO
standard. 15A NCAC 2B.0200
TSS
MA 30.0 mg/1
WA 45.0 mg/1
No change to limits
Decreased monitoring
frequency: 2x/week
TBEL. Secondary treatment
standards/40 CFR 133 / 15A NCAC
2B .0406
NH3-N
Summer:
MA 14.8 mg/1
WA 35.0 mg/1
Winter:
Monitor 3x/week
No change to limits
Decreased monitoring
frequency: 2x/week
WQBEL. Based on protection of
State WQ criteria. 15A NCAC
2B.0200
pH
6.0 — 9.0 SU
No change
WQBEL. State WQ standard, 15A
NCAC 2B .0200
Fecal coliform
MA 200 /100m1
WA 400 /100m1
No change to limits
Decreased monitoring
frequency: 2x/week
WQBEL. State WQ standard, 15A
NCAC 2B .0200
TRC
DM 28 µg/1
No change
WQBEL. State WQ standard, 15A
NCAC 2B .0200
Temperature
Monitor Daily
No change
15A NCAC 02B .0500
DO
Monitor Daily
No change
15A NCAC 02B .0500
Mercury
Monitor Annually
Remove requirement
Consistent with 2012 Statewide
Mercury TMDL Implementation.
Page 9 of 11

Mercury
Minimization Plan
(MMP)
No requirement
Add MMP Special
Condition
Consistent with 2012 Statewide
Mercury TMDL Implementation.
Total Copper
Monitor Quarterly
No change
Reasonable Potential Analysis. One
sample exceeded WQ Standard. All
other samples <50% of allowable
concentration
Total Silver
Monitor Quarterly
Add requirement
Reasonable Potential Analysis. All
samples <5 ug/L. Permittee shall
sample to the PQL (<1.0 ug/L)
Total Nitrogen
Monitor Monthly
No change
15A NCAC 2B.0500
Total Phosphorus
Monitor Monthly
No change
15A NCAC 2B.0500.
Toxicity Test
Chronic limit, 5.4%
effluent
No change
WQBEL. No toxics in toxic
amounts. 15A NCAC 2B.0200 and
15A NCAC 2B.0500
Effluent Pollutant
Scan
3x per permit cycle
No change
40 CFR 122. Permittee shall monitor
in 2023, 2024, 2025.
Electronic
Reporting
Required
No change
In accordance with EPA Electronic
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: 9/2/2020
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 questions regarding any of the above information or on the attached permit, please contact
Cassidy Kurtz at [phone] or via email at [e-mail].
15. Fact Sheet Addendum (if applicable)
Were there any changes made since the Draft Permit was public noticed (Yes/No): YES
If Yes, list changes and their basis below: NA
Page 10 of 11

The draft permit was sent to the permittee, EPA Region IV, DWR Winston-Salem Regional Office, DWR
Aquatic Toxicology, DWR Operator Certification, and Virginia DEQ (Allan Brockenbrough). The
permittee was the only party to submit comments. The following changes were made to the draft permit
after the public notice period:
• Based on the City's comments, the facility components list on the Supplement to Permit Cover
Sheet has been updated as follows: replaced the aerobic digester with a CleanB treatment system;
removed the dissolved air flotation (DAF); modified the sludge lagoons to be singular; and
removed the polymer addition.
• The expiration date for the permit has been modified to more closely fit a 5-year permit cycle.
Accordingly, the specified years for the Effluent Pollutant Scans have been modified (2023, 2024,
2025). See Special Condition A. (3.).
• A notation was made concerning the Electronic Reporting Rule — NPDES Electronic Reporting
Rule — Phase 2 Extension. EPA extended the Phase 2 deadline to December 21, 2025 (See Special
Condition A. (5.)).
The following comment from the permittee did not result in a change to the draft permit:
• "Also, for the third bullet item, we would like to note that we are already monitoring silver and
copper for our LTMP, so we would like for both silver and copper to be removed from our
Effluent Limits page."
o Per internal guidance, quarterly monitoring for copper and silver will remain in the
permit. This monitoring does not add any additional requirements to the City since it is
part of the LTMP for pretreatment, but will ensure that the data is collected in the event
that the pretreatment monitoring requirements are modified prior to the expiration of the
NPDES permit.
16. Fact Sheet Attachments (if applicable)
• NH3/TRC WLA Calculations
• BOD & TSS Removal Rate Calculations
• Mercury TMDL Calculations
• Pretreatment Information Request Form
• RPA Sheets
o Input Information
o Data Analyzed
o Results Summary
o Dissolved to Total Metal Calculation
• WET Testing and Self -Monitoring Summary
• Data Summary for Reduced NPDES Permit Monitoring Frequency
• NPDES Implementation of Instream Dissolved Metals Standards — Freshwater Standards
• Water Compliance Inspection Report (September 13, 2019)
• Priority Pollutant Analysis Data (2015, 2016, 2017)
Page 11 of 11

Rockingham Now
Advertising Affidavit
1921 Vance Street
Reidsville, NC 27320
[phone] Fax: [phone]
NCDEQ-DIVISION OF WATER RESOURCES
1617 MAIL SERVICE CENTER
RALEIGH, NC 27699-1617
Account Number
4019534
Date
September 02, 2020
PO Number Order Category
Description
0000670264 Legal Notices
Public Notice
North Carolina Environmental Man-
agement Commission/NPDES Unit
1617 Mail Service Center
Raleigh. NC 27699-1617
Notice of Intent to Issue a NPDES
Wastewater Permit NC0025071
Mebane Bridge WWTP
The North Carolina Environmental
Management Commission proposes
to issue a NPDES wastewater dis-
charge permit to the person(s) listed
below- Written comments regarding
the proposed permit will be accept-
ed until 30 days after the publish
date of this notice- The Director of
the NC Division of Water Resources
(DWR) may hold a public hearing
should there be a significant degree
of public interest- Please mail com-
ments and/or information requests
to DWR at the above address- Inter-
ested persons may visit the DWR at
512 N- Salisbury Street. Raleigh, NC
to review information on file. Addi-
tional information on NPDES permits
and this notice may be found on our
website: http;//deq-nc-gov/about/di
visio ns/water-resources/water-
reso urces-perm its/wastewater-
branch/npdes-wastewater/publ ic-
notices.or by calling [phone]-
The City of Eden requested renewal
of permit NC0025071 for the Mebane
Bridge WWTP in Rockingham Coun-
ty; this permitted discharge Is treat-
ed domestic and industrial wastewa-
ter to Dan River, Roanoke River Ba-
sin.
Public Notice North Carolina Environmental Management Commission/NPDES Unit 1617 N
Publisher of the
Rockingham Now
Before the undersigned, a Notary Public of Guilford, North Carolina, duly commissioned,
qualified, and authorized by law to administer oaths, personally appeared the Publisher
Representative who by being duly sworn deposes and says: that he/she is the Publisher's
Representative of the Rockingham Now, engaged in the publishing of a newspaper known
as Rockingham Now, published, issued and entered as second class mail in the City of
Reidsville, in said County and State: that he/she is authorized to make this affidavit and
sworn statement: that the notice or other legal advertisement, a copy of which is attached
hereto, was published in the Rockingham Now on the following dates:
09/02/2020
and that the said newspaper in which such notice, paper document, or legal advertisement
was published was, at the time of each and every such publication, a newspaper meeting all
the requirements and qualifications of Section 1-597 of the General Statutes of North
Carolina and was a qualified newspaper with' the meaning of Section 1-597 oft e General
Statutes of North Carolina.
•
person making affidavit)
Sworn to and subscribed before me the 2 day of September, 2020
LEA ANNE LAMB
NOTARY PUBLIC
GUILFORD COUNTY, NC
My Commission Expires June 15, 2024
(Notary Public)
THIS IS NOT A BILL. PLEASE PAY FROM INVOICE. THANK YOU

NH3/TRC WLA Calculations
Facility: Mebane Bridge WWTP
PermitNo. NC0025071
Prepared By: Cassidy Kurtz
Enter Design Flow (MGD):
Enter s7Q10 (cfs):
Enter w7Q10 (cfs):
13.5
370
600
Total Residual Chlorine (TRC)
Daily Maximum Limit (ug/I)
s7Q10 (CFS)
DESIGN FLOW (MGD)
DESIGN FLOW (CFS)
STREAM STD (UG/L)
Upstream Bkgd (ug/l)
IWC (%)
Allowable Conc. (ugll)
Fecal Coliform
Monthly Average Limit:
(If DF >331; Monitor)
(If DF<331; Limit)
Dilution Factor (DF)
370
13.5
20.925
17.0
0
5.35
318
Ammonia (Summer)
Monthly Average Limit (mg NH3-N/I)
s7Q10 (CFS)
DESIGN FLOW (MGD)
DESIGN FLOW (CFS)
STREAM STD (MG/L)
Upstream Bkgd (mg/I)
IWC (%)
Allowable Conc. (mg/I)
Ammonia (Winter)
Monthly Average Limit (mg NH3-N/I)
w7Q10 (CFS)
200/100m1 DESIGN FLOW (MGD)
DESIGN FLOW (CFS)
STREAM STD (MG/L)
18.68 Upstream Bkgd (mg/I)
IWC (%)
Allowable Conc. (mg/I)
Total Residual Chlorine
1. Cap Daily Max limit at 28 ug/I to protect for acute toxicity
Ammonia (as NH3-N)
1. If Allowable Conc > 35 mg/I, Monitor Only
2. Monthly Avg limit x 3 = Weekly Avg limit (Municipals)
3. Monthly Avg limit x 5 = Daily Max limit (Non-Munis)
If the allowable ammonia concentration is > 35 mg/L, no limit shall be imposed
370
13.5
20.925
1.0
0.22
5.35
14.8
600
13.5
20.925
1.8
0.22
3.37
47.1
Fecal Coliform
1. Monthly Avg limit x 2 = 400/100 ml = Weekly Avg limit (Municipals) = Daily Max limit (Non -Muni)

NC0025071 Mebane Bridge WWTP 8/31/2020
BOD monthly removal rate
Month RR (%) Month RR (%)
January-17
February-17
March-17
April-17
May-17
June-17
July-17
August-17
September-17
October-17
November-17
December-17
January-18
February-18
March-18
April-18
May-18
June-18
July-18
August-18
September-18
October-18
November-18
December-18
January-19
February-19
March-19
April-19
May-19
June-19
94.33
97.33
96.67
95.95
94.77
96.39
98.26
98.69
97.43
98.32
97.22
98.50
98.29
98.03
96.72
96.65
96.50
96.97
97.44
97.78
97.41
96.57
97.17
96.49
96.93
95.67
97.24
97.40
96.98
97.28
July-19
August-19
September-19
October-19
November-19
December-19
January-20
February-20
March-20
April-20
May-20
June-20
July-20
August-20
September-20
October-20
November-20
December-20
January-21
February-21
March-21
April-21
May-21
June-21
July-21
August-21
September-21
October-21
November-21
December-21
Overall BOD removal rate
97.18
97.57
97.92
96.88
96.89
98.15
97.57
96.33
96.81
97.16
95.27
L 97.05
TSS monthly removal rate
Month RR (%) Month RR (%)
January-17
February-17
March-17
April-17
May-17
June-17
July-17
August-17
September-17
October-17
November-17
December-17
January-18
February-18
March-18
April-18
May-18
June-18
July-18
August-18
September-18
October-18
November-18
December-18
January-19
February-19
March-19
April-19
May-19
June-19
98.04
98.56
98.40
97.40
97.86
98.52
98.71
98.48
97.11
97.42
95.89
96.65
96.94
96.75
96.23
97.25
97.54
97.57
97.31
97.74
97.61
97.25
95.99
89.08
92.59
92.36
95.13
95.96
97.84
97.49
July-19
August-19
September-19
October-19
November-19
December-19
January-20
February-20
March-20
April-20
May-20
June-20
July-20
August-20
September-20
October-20
November-20
December-20
January-21
February-21
March-21
April-21
May-21
June-21
July-21
August-21
September-21
October-21
November-21
December-21
Overall TSSD removal rate
97.46
97.62
97.60
96.27
94.95
95.65
96.08
97.16
96.20
95.90
91.21
96.53

8/31/20 WQS = 12 ng/L
Facility Name Mebane Bridge WWTP / NC0025071
/Permit No. :
MERCURY WQBEL/TBEL EVALUATION V:2013-6
Total Mercury 1631E PQL = 0.5 ng/L 7Q10s =
Date Modifier Data Entry Value Permitted Flow =
3/8/16 2.07
6/7/16 1.54
9/13/16 1.38
12/6/16 2.76
3/7/17 3.64
6/6/17 1.59
9/12/17 3.14
12/5/17 2.94
3/6/18 2.41
6/5/18 1.69
9/11/18 2.34
12/4/18 3.18
3/5/19 4.28
6/4/19 2.48
9/10/19 1.12
12/3/19 4.82
3/3/20 3.79
No Limit Required
MMP Required
2.07
1.54
1.38
2.76
3.64
1.59
3.14
2.94
2.41
1.69
2.34
3.18
4.28
2.48
1.12
4.82
3.79
386.000
13.500
cfs
WQBEL = 233.36 ng/L
47 ng/L
1.9 ng/L - Annual Average for 2016
2.8 ng/L - Annual Average for 2017
2.4 ng/L - Annual Average for 2018
3.2 ng/L - Annual Average for 2019
3.8 ng/L - Annual Average for 2020

Mebane Bridge WWTP / NC0025071
Mercury Data Statistics (Method 1631E)
2016
2017
2018
2019
2020
# of Samples
4
4
4
4
1
Annual Average, ng/L
1.9
2.8
2.4
3.2
3.8
Maximum Value, ng/L
2.76
3.64
3.18
4.82
3.79
TBEL, ng/L
47
WQBEL, ng/L
233.4

NPDES/Aquifer Protection Permitting Unit Pretreatment Information Request Form
PERMIT WRITERS - AFTER vou get this form back
PERMIT WRITER COMPLETES THIS PART:
f
from
Check all that apply
PERCS if LTMP/STMP data we said should be
Date of Request
11/28/2018
municipal renewal
X
on DMRs is not really there, so we can get it for you
Requestor
Cassidy Kurtz
new industries
(or NOV POTW).
Facility Name
Mebane Bridge WWTP
WWTP expansion
- Notify PERCS if you want us to keep a specific POC
in LTMP/STMP so will have data for next permit
Permit Number
NC0025071
Speculative limits
you
renewal.
Region
Winston-Salem
stream reclass.
- Email PERCS draft permit, fact sheet, RPA.
Basin
Roanoke
outfall relocation
- Send PERCS paper copy of permit (w/o NPDES
7Q10 change
boilerplate), cover letter, final fact sheet. Email RPA if
other
changes.
other
check
applicable PERCS staff:
Other Comments to PERCS:
BRD, CPF, CTB, FRB, TAR
Rug Mill rugs
Vivien Zhong (807-6310)
Facility is rated 13.5 MGD wtih 3 Sills (Karastan - packaged
broadloom / Duke Energy - leachate from coal ash landfills /
X
CHO, HIW, LTN, LUM, NES, NEW, ROA, YAD
and carpets
Weil McLain - residential and commercial boilers, sheet metal forming,
Monti Hassan (807-6314)
finishing and assembly) listed in its application.
PERCS
Status
V
PRETREATMENT STAFF COMPLETES THIS PART:
of Pretreatment Program (check all that apply)
Flow, MGD
P
A tua
Time period for Actual
STMP time frame:
Industrial
bed
i.
�>.Most
recent:
Uncontrollable
n/a
Next Cycle:
POC In LTMPI
STMP
Parameter of
Concern (POC)
Check List
POC due to
NPDESI Non-Dlsch
Permit Limit
Required by
EPA,
Required
by 503
Sludge"
POC due
to SR?"
POTW POC
(Explain
below)""
STMP
Effluent
Freq
LTMP
Efflue
F
4
Q M
,/
S3
4
Q M
Quarterly
�r
V
4
Q M
M=Mon fly
/
Arsenic
J
Cadmium
4
4
Q M
V1
Chromium
✓
4
Q M
4
C pper
✓
V
✓
✓
4
Q M
anide
Vc
-
4
QM
Is all data on DMRs?
-
dead
V
Q
YES
ke-
,7yercury
✓
V-
4
Q M
NO (attach data)
✓
Molybdenum
✓/
t7
4
Q M
d_Nickel
1r
✓
4
Q M
V,Silver
/
V-
4
Q M
.
Selenium
f✓
4
Q M
VI
Zinc
/
4✓
4
Q M
Is data in spreadsheet?
/
Total Nitrogen
5/
4
Q M
YES (email to writer)
.-
jiosphorus
f
4
Q M
NO
✓
4
Q M
,�yt'
g(Cy
�i
V
4
Q M
4
Q M
4
Q M
'Always in the LTMP/STMP " Only in LTMP/STMP if sludge land app or composte (dif POCs for incinerators)
***Only in LTMP/STMP while SIU still discharges to POTW """" Only in LTMP/STMP when pollutant is still of concem to POTW
Comments to Permit Writer (ex., explanation of anv POCs; info vou have on IV relate investig tions.into NPD problems):
n'abfk4 131�i�, W rugs - -111 v►ncv,, or' to elk 1
(IA
((kin! t ,
2 CA + . (el �I i_ L , • 1 /t tie \ I Li-- r. 4--." ‘ '\ A ► _ _ 11,u.nf ClIt AI
PERC NPDES PretrealmeM.requestform.may201e.xlsx
Revlsed: July 24, 2007

Freshwater RPA - 95% Probability/95% Confidence Using Metal Translators
MAXIMUM DATA POINTS = 58
REQUIRED DATA ENTRY
Table 1. Project Information
❑ CHECK IF HQW OR ORW WQS
Facility Name
WWTP/WTP Class
NPDES Permit
Outfall
Flow, Qw (MGD)
Receiving Stream
HUC Number
Stream Class
❑ Apply WS Hardness WQC
7Q10s (cfs)
7Q10w (cfs)
30Q2 (cfs)
QA (cfs)
1Q10s (cfs)
Mebane Bridge WWTP
IV
NC0025071
001
13.500
Dan River
03010103
370.00
600.00
740.00
1621.00
299.26
Effluent Hardness
69.33 mg/L (Avg)
Upstream Hardness
25 mg/L (Avg)
Combined Hardness Chronic
27.37 mg/L
Combined Hardness Acute
27.9 mg/L
Data Source(s)
❑ CHECK TO APPLY MODEL
Table 2. Parameters of Concern
Par01
Par02
Par03
Par04
Par05
ParO�
Par07
Par08
Par09
Par10
Par11
Par12
Par13
Par14
Par15
Par16
Par17
Par18
Par19
Par20
Par21
Par22
Par23
Par24
Name
WQS Type Chronic Modifier
Acute
PQL Units
Arsenic
Aquactic Life
C
150
FW
340
ug/L
Arsenic
Human Health
Water Supply
C
10
HH/WS
N/A
ug/L
Beryllium
Aquatic Life
NC
6.5
FW
65
ug/L
Cadmium
Aquatic Life
NC
0.6318
FW
3.5652
ug/L
Chlorides
Aquatic Life
NC
230
FW
mg/L
Chlorinated Phenolic Compounds
Water Supply
NC
1
A
ug/L
4 Total Phenolic Compounds
Aquatic Life
NC
300
A
ug/L
Chromium III
Aquatic Life
NC
126.8093
FW
990.1261
ug/L
Chromium VI
Aquatic Life
NC
11
FW
16
pg/L
Chromium, Total
Aquatic Life
NC
N/A
FW
N/A
pg/L
Copper
Aquatic Life
NC
8.5156
FW
11.6118
ug/L
Cyanide
Aquatic Life
NC
5
FW
22
10
ug/L
Fluoride
Aquatic Life
NC
1,800
FW
ug/L
Lead
Aquatic Life
NC
3.2576
FW
85.3987
ug/L
Mercury
Aquatic Life
NC
12
FW
0.5
ng/L
Molybdenum m
Human Health
NC
2000
HH
ug/L
Nickel
Aquatic Life
NC
40.2000
FW
367.7932
pg/L
Nickel
Water Supply
NC
25.0000
WS
N/A
pg/L
Selenium
Aquatic Life
NC
5
FW
56
ug/L
Silver
Aquatic Life
NC
0.06
FW
0.3579
ug/L
Zinc
Aquatic Life
NC
136.8549
FW
137.9443
ug/L
25071 - RPA C, input
8/31/2020

REASONABLE POTENTIAL ANALYSIS
H1
Use"PASTE SPECIAL-
H2
Use"PASTE SPECIAL-
Par01 & Par02
Use"PASTE
Effluent Hardness
Values" then "COPY" .
Maximum data points
Upstream Hardness
Values" then "COPY" .
Maximum data points
Arsenic
SPECIAL -Values"
then "COPY" .
= 58
= 58
Maximum data points
Date
Data BDL=1/2DL Results
Date
Data BDL=1/2DL Results
Date
Data
BDL=1/2DL
Results
=58
1
6/2/2015
53.2 53.2 Std Dev.
15.5388
1
25 25 Std Dev.
N A
1 3/8/2016
<
10
5
Std Dev.
0.0000
2
9/13/2016
70.6 70.6 Mean 69.3333
2
Mean 25.0000
2 6/7/2016
<
10
5
Mean 5.0000
3
9/12/2017
84.2 84.2 C.V. (default) 0.6000
3
C.V. 0.0000
3 9/13/2016
<
10
5
C.V. 0.0000
4
n 3
4
n 1
4 12/6/2016
<
10
5
n 17
5
10th Per value 56.68 mg/L
5
10th Per value 25.00 mg/L
5 3/7/2017
<
10
5
6
Average Value 69.33 mg/L
6
Average Value 25.00 mg/L
6 6/6/2017
<
10
5
Mult Factor = 1.00
7
Max. Value 84.20 mg/L
7
Max. Value 25.00 mg/L
7 9/12/2017
<
10
5
Max. Value 5.0 ug/L
8
8
8 12/5/2017
<
10
5
Max. Pred Cw 5.0 ug/L
9
9
9 3/6/2018
<
10
5
10
10
10 6/5/2018
<
10
5
11
11
11 9/11/2018
<
10
5
12
12
12 12/4/2018
<
10
5
13
13
13 3/5/2019
<
10
5
14
14
14 6/4/2019
<
10
5
15
15
15 9/10/2019
<
10
5
16
16
16 12/3/2019
<
10
5
17
17
17 3/3/2020
<
10
5
18
18
18
19
19
19
20
20
20
25071 - RPA C, data
8/31/2020

REASONABLE POTENTIAL ANALYSIS
Par03
Use"PASTE
SPECIAL -Values"
Par04
Use"PASTE
SPECIAL -Values
Par07
Use "PASTE SPECIAL -
Beryllium
Cadmium
Total Phenolic Compounds
then "COPY".
then "COPY".
Values" then "COPY".
Maximum data
Maximum data
Maximum data points =
points = 58
points = 58
58
Date
Data
BDL=1/2DL
Results
Date
Data
BDL =1/2DL
Results
Date
Data BDL=1/2DL Results
1
9/13/2016
<
1
0.5
Std Dev.
0.0000
1
3/8/2016
1.2
1.2
Std Dev.
0.1698
1 3/8/2016
17 17 Std Dev.
5.6526
2
9/12/2017
<
1
0.5
Mean 0.5000
2
6/7/2016
<
1
0.5
Mean 0.5412
2 6/7/2016
13 13 Mean 9.4286
3
C.V. (default) 0.6000
3
9/13/2016
<
1
0.5
C.V. 0.3137
3 9/13/2016
16 16 C.V. (defa 0.6000
4
n 2
4
12/6/2016
<
1
0.5
n 17
4 12/6/2016
< 10 5 n 7
5
5
3/7/2017
<
1
0.5
5 3/7/2017
< 10 5
6
Mult Factor = 3.79
6
6/6/2017
<
1
0.5
Mult Factor = 1.22
6 6/6/2017
< 10 5 Mult Factc 2.01
7
Max. Value 0.50 ug/L
7
9/12/2017
<
1
0.5
Max. Value 1.200 ug/
7 9/12/2017
< 10 5 Max. Valu, 17.0 ug/L
8
Max. Pred Cw 1.90 ug/L
8
12/5/2017
<
1
0.5
Max. Pred Cw 1.464 ug/
8
Max. Pred 34.2 ug/L
9
9
3/6/2018
<
1
0.5
9
10
10
6/5/2018
<
1
0.5
10
11
11
9/11/2018
<
1
0.5
11
12
12
12/4/2018
<
1
0.5
12
13
13
3/5/2019
<
1
0.5
13
6
14
14
6/4/2019
<
1
0.5
14
15
15
9/10/2019
<
1
0.5
15
16
16
12/3/2019
<
1
0.5
16
17
17
3/3/2020
<
1
0.5
17
18
18
18
19
19
19
20
20
20
25071 - RPA C, data
8/31/2020

REASONABLE POTENTIAL ANALYSIS
Par10
Chromium, Total
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
Date Data
3/8/2016 5.5
6/7/2016 5
9/13/2016 5
12/6/2016 5
3/7/2017 5
6/6/2017 5
9/12/2017 5
12/5/2017 5
3/6/2018 5
6/5/2018 5
9/11/2018 5
12/4/2018 5
3/5/2019 5
6/4/2019 5
9/10/2019 5
12/3/2019 5
3/3/2020 5
Use "PASTE SPECIAL -
Values" then "COPY" .
Maximum data points
= 58
BDL=1/2DL Results
5.5 Std Dev. 0.7276
2.5 Mean 2.6765
2.5 C.V. 0.2719
2.5 n 17
2.5
2.5 Mult Factor = 1.19
2.5 Max. Value 5.5 pg/L
2.5 Max. Pred Cw 6.5 pg/L
2.5
2.5
2.5
2.5
2.5
2.5
2.5
2.5
2.5
Pal
Copper
Use"PASTE SPECIAL -
Values" then "COPY" .
Maximum data points
= 58
Date Data BDL=1/2DL Results
1 3/8/2016 690 690 Std Dev. I63.2529
2 6/7/2016 16 16 Mean 57.1353
3 9/13/2016 11 11 C.V. 2.8573
4 12/6/2016 26 26 n 17
5 3/7/2017 30 30
6 6/6/2017 9.2 9.2 Mult Factor = 2.66
7 9/12/2017 18 18 Max. Value 690.00 ug/L
8 12/5/2017 32 32 Max. Pred Cw 1835.40 ug/L
9 3/6/2018 8.4 8.4
10 6/5/2018 8.7 8.7
11 9/11/2018 13 13
12 12/4/2018 25 25
13 3/5/2019 13 13
14 6/4/2019 13 13
15 9/10/2019 16 16
16 12/3/2019 24 24
17 3/3/2020 18 18
18
19
20
Par12
Cyanide
Use "PASTE SPECIAL -
Values" then "COPY" .
Maximum data points
= 58
Date Data BDL=1/2DL Results
1 3/8/2016 < 8 5 Std Dev. 0.0000
2 6/7/2016 9 5 Mean 5.00
3 9/13/2016 < 8 5 C.V. 0.0000
4 12/6/2016 < 8 5 n 17
5 3/7/2017 < 8 5
6 6/6/2017 < 8 5 Mult Factor = 1.00
7 9/12/2017 < 8 5 Max. Value 5.0 ug/L
8 12/5/2017 < 8 5 Max. Pred Cw 5.0 ug/L
9 3/6/2018 10 5
10 6/5/2018 < 8 5
11 9/11/2018 < 8 5
12 12/4/2018 < 8 5
13 3/5/2019 < 8 5
14 6/4/2019 < 8 5
15 9/10/2019 < 8 5
16 12/3/2019 < 8 5
17 3/3/2020 < 8 5
18
19
20
25071 - RPA C, data
8/31/2020

REASONABLE POTENTIAL ANALYSIS
Par14
Use "PASTE SPECIAL- Par16
Lead Values" then "COPY" .
Maximum data points
= 58
Date BDL=1/2DL Results
1 3/8/2016 6.1 6.1 Std Dev. 0.8731
2 6/7/2016 < 5 2.5 Mean 2.7118
3 9/13/2016 < 5 2.5 C.V. 0.3220
4 12/6/2016 < 5 2.5 n 17
5 3/7/2017 < 5 2.5
6 6/6/2017 < 5 2.5 Mult Factor = 1.23
7 9/12/2017 < 5 2.5 Max. Value 6.100 ug/L
8 12/5/2017 < 5 2.5 Max. Pred Cw 7.503 ug/L
9 3/6/2018 < 5 2.5
10 6/5/2018 < 5 2.5
11 9/11/2018 < 5 2.5
12 12/4/2018 < 5 2.5
13 3/5/2019 < 5 2.5
14 6/4/2019 < 5 2.5
15 9/10/2019 < 5 2.5
16 12/3/2019 < 5 2.5
17 3/3/2020 < 5 2.5
18
19
20
Molybdenum
Date Data BDL=1/2DL Results
1 3/8/2016 < 5 2.5 Std Dev.
2 6/7/2016 < 5 2.5 Mean
3 9/13/2016 < 5 2.5 C.V.
4 12/6/2016 < 5 2.5 n
5 3/7/2017 < 5 2.5
6 6/6/2017 < 5 2.5 Mult Factor =
7 9/12/2017 6.2 6.2 Max. Value
8 12/5/2017 < 5 2.5 Max. Pred Cw
9 3/6/2018 9.2 9.2
10 6/5/2018 10 10
11 9/11/2018 8.6 8.6
12 12/4/2018 5.2 5.2
13 3/5/2019 5.2 5.2
14 6/4/2019 6.7 6.7
15 9/10/2019 5.4 5.4
16 12/3/2019 6.6 6.6
17 3/3/2020 < 5 2.5
18
19
20
Use"PASTE SPECIAL -
Values" then "COPY" .
Maximum data points
= 58
Par17 & Par18
Nickel
Date Data BDL=1/2DL Results
2.6519 1 3/8/2016 < 5 2.5 Std Dev.
4.8882 2 6/7/2016 < 5 2.5 Mean
0.5425 3 9/13/2016 < 5 2.5 C.V.
17 4 12/6/2016 < 5 2.5 n
5 3/7/2017 < 5 2.5
1.40 6 6/6/2017 < 5 2.5 Mult Factor =
10.0 ug/L 7 9/12/2017 < 5 2.5 Max. Value
14.0 ug/L 8 12/5/2017 < 5 2.5 Max. Pred Cw
9 3/6/2018 < 5 2.5
10 6/5/2018 < 5 2.5
11 9/11/2018 < 5 2.5
12 12/4/2018 < 5 2.5
13 3/5/2019 < 5 2.5
14 6/4/2019 < 5 2.5
15 9/10/2019 < 5 2.5
16 12/3/2019 < 5 2.5
17 3/3/2020 < 5 2.5
18
19
20
Use "PASTE SPECIAL -
Values" then "COPY" .
Maximum data points
= 58
0.0000
2.5000
0.0000
17
1.00
2.5 pg/L
2.5 pg/L
25071 - RPA C, data
8/31/2020

REASONABLE POTENTIAL ANALYSIS
Par19
Use "PASTE SPECIAL-
Par20
Use "PASTE SPECIAL-
Par21
Use "PASTE SPECIAL -
Selenium
Values" then "COPY" .
Maximum data points
Silver
Values" then "COPY" .
Maximum data points
ZIfC
Values" then "COPY" .
Maximum data points
Date Data BDL=1/2DL Results
= 58
Date Data BDL=1/2DL Results
= 58
Date Data BDL=1/2DL Results
= 58
I
1
4
10
11
12
13
14
15
16
17
18I
19
20
3/8/2016 < 10
2 6/7/2016 < 10
3 9/13/2016 < 10
12/6/2016 < 10
5 3/7/2017 < 10
6 6/6/2017 < 10
7 9/12/2017 < 10
8 12/5/2017 < 10
9 3/6/2018 < 10
6/5/2018 < 10
9/11/2018 < 10
12/4/2018 < 10
3/5/2019 < 10
6/4/2019 < 10
9/10/2019 < 10
12/3/2019 < 10
3/3/2020 < 10
5 Std Dev. 0.0000
5 Mean 5.0000
5 C.V. 0.0000
5 n 17
5
5 Mult Factor = 1.00
5 Max. Value 5.0 ug/L
5 Max. Pred Cw 5.0 ug/L
5
5
5
5
5
5
5
5
5
1 3/8/2016 < 5 2.5 Std Dev. 0.0000
2 6/7/2016 < 5 2.5 Mean 2.5000
3 9/13/2016 < 5 2.5 C.V. 0.0000
4 12/6/2016 < 5 2.5 n 17
5 3/7/2017 < 5 2.5
6 6/6/2017 < 5 2.5 Mult Factor = 1.00
7 9/12/2017 < 5 2.5 Max. Value 2.500 ug/L
8 12/5/2017 < 5 2.5 Max. Pred Cw 2.500 ug/L
9 3/6/2018 < 5 2.5
10 6/5/2018 < 5 2.5
11 9/11/2018 < 5 2.5
12 12/4/2018 < 5 2.5
13 3/5/2019 < 5 2.5
14 6/4/2019 < 5 2.5
15 9/10/2019 < 5 2.5
16 12/3/2019 < 5 2.5
17 3/3/2020 < 5 2.5
18
19
20
1 3/8/2016 150 150 Std Dev. 35.2212
2 6/7/2016 25 25 Mean 42.1765
3 9/13/2016 29 29 C.V. 0.8351
4 12/6/2016 87 87 n 17
5 3/7/2017 71 71
6 6/6/2017 28 28 Mult Factor = 1.61
7 9/12/2017 50 50 Max. Value 150.0 ug/L
8 12/5/2017 74 74 Max. Pred Cw 241.5 ug/L
9 3/6/2018 29 29
10 6/5/2018 20 20
11 9/11/2018 19 19
12 12/4/2018 27 27
13 3/5/2019 18 18
14 6/4/2019 22 22
15 9/10/2019 17 17
16 12/3/2019 29 29
17 3/3/2020 22 22
18
19
20
25071 - RPA C, data
8/31/2020

Mebane Bridge WWTP
NC0025071
Freshwater RPA - 95% Probability/95% Confidence Using Metal Translators
MAXIMUM DATA POINTS = 58
Qw (MGD) = 13.5000
1Q1OS (cfs) = 299.26
7Q1OS (cfs) = 370.00
7Q1OW (cfs) = 600.00
30Q2 (cfs) = 740.00
Avg. Stream Flow, QA (cfs) = 1621.00
Receiving Stream: Dan River HUC 03010103
WWTP/WTP Class: IV
IWC% @ 1Q1OS = 6.535284289
IWC% @ 7Q1OS = 5.352689135
IWC% @ 7Q1OW = 3.369972219
IWC% @ 30Q2 = 2.749942504
IW%C @ QA = 1.274418746
Stream Class: C
Outfall 001
Qw = 13.5 MGD
COMBINED HARDNESS (mg/L)
Acute = 27.9 mg/L
Chronic = 27.37 mg/L
PARAMETER
TYPE
NC STANDARDS OR EPA CRITERIA
_1cn
a
D
REASONABLE POTENTIAL RESULTS
RECOMMENDED ACTION
Applied Chronic Standard Acute
n # Det. Max Pred Cw Allowable Cw
Arsenic
Arsenic
C
C
150 FW(7Q10s) 340
10 HH/WS(Qavg)
ug/L
ug/L
17 0
5.0
NO DETECTS
Acute (FW): 5,202.5
_ _ _ _ _ _
Chronic (FW): 2,802.3 - -
Max MDL = 10 _ _ _
Chronic (HH): 784.7
Max MDL = 10
- - - - - - - - - - - - - - - - - - - - - - - - - - - - -
No RP, Predicted Max < 50% of Allowable Cw - No
Monitoring required
Beryllium
NC
6.5 FW(7Q10s) 65
ug/L
2 0
Note: n < 9
Limited data set
1.90
C.V. (default)
NO DETECTS
Acute: 994.60
Chronic:121.43
Max MDL = 1
No RP, Predicted Max < 50% of Allowable Cw - No
Monitoring required
Cadmium
NC
0.6318 FW(7Q10s) 3.5652
ug/L
17 1
1.464
Acute: 54.552
__ _ _______ _ _
Chronic: 11.803
No value > Allowable Cw
_ _ _ _ _ _ _ _ _ _ _ _ ___
No RP, Predicted Max < 50% of Allowable Cw - No
Monitoring required
Chlorinated Phenolic Compounds
NC
1 A(30Q2)
ug/L
0 0
N/A
Acute: NO WQS
-- _ _ _
------ --------------------------------
Chronic: 36.4
Total Phenolic Compounds
NC
300 A(30Q2)
ug/L
7 3
Note: n < 9
Limited data set
34.2
C.V. (default)
Acute: NO WQS
Chronic:10,909.3
No value > Allowable Cw
No RP, Predicted Max < 50% of Allowable Cw - No
Monitoring required
Chromium III
NC
126.8093 FW(7Q10s) 990.1261
µg/L
0 0
N/A
Acute: 15,150.5
-- _ ----- _ _ -------------------------------
Chronic: 2,369.1
Chromium VI
NC
11 FW(7Q10s) 16
µg/L
0 0
N/A
Acute: 244.8
-- _ ------ _ _ --------------------------------
Chronic: 205.5
Chromium, Total
NC
µg/L
Tot Cr value(
17 1
) > 5 but < Cr VI
6.5
Allowable Cw
Max reported value = 5.5
a: No monitoring required if all Total Chromium
samples are < 5 pg/L or Pred. max for Total Cr is <
allowable Cw for Cr VI.
Copper
NC
8.5156 FW(7Q10s) 11.6118
ug/L
17 17
1,835.40
Acute: 177.68
__ _ _______ _ _
Chronic: 159.09
1 value(s) > Allowable Cw
_ _ _ _ _ _ _ _ _ _ _ _ _ _
Apply quarterly monitoring. One value > allowable, all
others <50% allowable.
Cyanide
NC
5 FW(7Q10s) 22
10
ug/L
17 2
5.0
Acute: 336.6
__ _ _______ ___
Chronic: 93.4
_ _ _ _ _ _ _ _ _ _ _ _ ___
No RP, Predicted Max < 50% of Allowable Cw - No
Page 1 of 2
25071 - RPA C, rpa
8/31/2020

Mebane Bridge WWTP
•
Outfall 001
rt
rvranslators
AJULDu 1'I
rresnwater
r ri& - uo io rrooaonity/y37
o
l.nuence using
orl
ivietai T
No value > Allowable Cw
lAw = 13.D 1v1vu
Monitoring required
Lead
NC
3.2576
FW(7Q10s)
85.3987
ug L
17
I
7.503
Acute: 1,306.732
__ _ _______ _ _
Chronic: 60.860
No value > Allowable Cw
_ _ _ _ _ _ _ _ _ _ _ _ ___
No RP, Predicted Max < 50% of Allowable Cw - No
Monitoring required
Molybdenum
NC
2000
HH(7Q10s)
ug/L
17
9
14.0
Acute: NO WQS
__ _ _____ _ _ _
Chronic: 37,364.4
No value > Allowable Cw
_ _ _ _ _ _ _ _ _ _ _ _ ___
No RP, Predicted Max < 50% of Allowable Cw - No
Monitoring required
Nickel
Nickel
NC
NC
40.2000
25.0000
FW(7Q10s)
WS(7Q10s)
367.7932
µg/L
µg/L
17
0
2.5
NO DETECTS
Acute (FW): 5,627.8
__ _ _
Chronic (FW): — _ _--------------------------
751.0
Max MDL =5 _ _ _ _
Chronic (WS): 467.1
Max MDL = 5
— —
_ _ _ _ _ _ _ _ _ _ _ _ _ _
No RP, Predicted Max < 50% of Allowable Cw - No
Monitoring required
Selenium
NC
5
FW(7Q10s)
56
ug/L
17
0
5.0
NO DETECTS
Acute: 856.9
__ _ _______ ___
Chronic 93.4
Max MDL = 10
_ _ _ _ _ _ _ _ _ _ _ _ ___
No RP, Predicted Max < 50% of Allowable Cw - No
Monitoring required
Silver
NC
0.06
FW(7Q10s)
0.3579
ug/L
17
0
2.500
NO DETECTS
Acute: 5.477
__ _ _______ ___
Chronic: 1.121
Max MDL = 5
_ _ _ _ _ _ _ _ _ _ _ _ ___
All samples <5 ug/L. Permittee shall sample to PQL
(1.0 ug/L)
Zinc
NC
136.8549
FW(7Q10s)
137.9443
ug/L
17
17
241.5
Acute: 2,110.8
__ _ _ _____ _ _ _
Chronic: 2,556.8
No value > Allowable Cw
_ _ _ _ _ _ _ _ _ _ _ _ ___
No RP, Predicted Max < 50% of Allowable Cw - No
Monitoring required
Page 2 of 2
25071 - RPA C, rpa
8/31/2020

Date: 8/31/2020
Dissolved to Total Metal Calculator
Do NOT enter any data directly into this spreadsheet.
Enter data onto 'Table 1" under the Input Sheet and enter
"Effluent Hardness" under the Data Sheet.
In accordance with 40 CFR 122.45 (c ), permits are, have and
must be written as total metals.
This calculator has been inserted into the RPA to calculate
Total Metal allowable allocations once Table 1 has been
completed (Input Sheet) and Effluent hardness has been
entered (Data Sheet).
1) Following the spreadsheet from left to right. First
the allowable allocations for the dissolved metals will
appear for all the metals listed once Table 1 is complete
and effluent hardness entered. Use a default value of 25
mg/L if no hardness data is available. Second
the Dissolved Metal allocations are divided by the
Translators to determine the Total Metals that can be
allocated to the Permittee. These Total Metals values are
automatically inserted into Table 2 and are the allowable
Total Metal allocations determined for the Permittee prior
to allowing for dilution. See Input sheet Table 2. The final
acute and chronic values shown under the RPA sheet are
the Total Metal values listed in Table 2 divided by the
acute and chronic IWC, respectively.
2) The Translators used in the freshwater RPA are the
Partition Coefficients published by US EPA in 1984. They (d) = dissolved metal standard. See ISA NCAC 02B.0211 for more information.
are TSS dependent equations and can be found listed with (h)=hardness-dependent dissolved metal standard. See 15A NCAC 02B .0211 for more information.
the WQS hardness dependent equations under the sheet (t) = based upon measurement of total recoveable metal. See 15A NCAC 026.0211 for more information.
The Human Health standard for Nickel in Water Supply Streams is 25 mg/L which is Total Recoverable metal standard.
labeled Equations. A fixed TSS value of 10 mg/L is used to The Human Health standard for Arsenic is 10 µg/L which is Total Recoverable metal standard.
calculate the Translator values.
3) Pretreatment Facilities - PERCS will need a copy of the
Dissolved to Total Metal Calculator spreadsheet and the
RPA sheet along with the Final Permit. Pretreatment
Facilities are required to renew their Headwords Analysis
after renewal of their permits. Since all their metal
allocations are likely to change PERCS needs to see any
new metal permit limits and the allowable allocations for
the dissolved metals to assess Maximum Allowable
Headworks Loading (MARL) numbers for each metal based
on the Combined Hardness values used in the permit
writers RPA calculations.
4) For Cadmium, Lead, Nickel, Chromium and Beryllium, if all
the effluent sampling data for the last three to five years
shows the pollutant at concentrations less than the
Practical Quantitative Level (PQL), it is not likely a limit or
monitoring will be put in the permit. However, if the
estimated NPDES permit limit is less than the Practical
Quantitative Limit (particularly, Cadmium and Lead) and
the pollutant is believed to be present, to assess
compliance with the new standards and for future permit
limit development, monitoring for the pollutant will be
required. If the facility is monitoring for the pollutant in its
Pretreatment LTMP, no monitoring is needed in the
FACILITY: Mebane Bndge WWTP Outfall 001
NPDES PERMIT: NC0025071
Dissolved to Total Metal Calculator
In accordance with Federal Regulations, permit limitations must be written as Total Metals per 40 CFR 122.45(c)
Receiving
Stream
summer
7010 (CFS)
70.0000
Receiving
Stream summer
7Q10 (MGD)
Rec. Stream
1010
[MGD]
193.0710
NPDES
Flow Limit
MGD
5000
Total Suspended
Solids
-Fixed Value-
(mg/L)
Combined
Hardness
chronic
(mg/L)
Combined
Hardness
Acute
(mg/L)
Instream
Wastewater
Concentmtm
(Chronic)
27.373 27.897 5.3527
Instream
Wastewater
Concentration
(Acute)
6.5353
Upstream
Hardness
Average (mg/L)
25
Effluent
Hardness
Average
(mg/L)
69.33333
Upstream Hard Avg (mg/L) = 25
EFF Hard Avg (mg/L) = 69.33333
PARAMETER
Dissolved Metals Criteria
after applying hardness
equation
Chronic
Acute
man
man
US EPA
Translators- using
Default Partition
Coefficients
(streams)
Total Metal Criteria Total Metal =
Dissolved Metal Translator
Chronic
Acute
No/11
tun/Il
Cadmium (d)
0.16
0.90
0.252
0.63
3.57
Cd -Trout streams
0.16
0.56
0.252
0.63
2.22
Chromium III (d)())
26
200
0.202
126.81
990.13
Chromium VI (d)
11
16
1.000
11.00
16.00
Chromium, Total (t)
N/A
N/A
Copper (d)(h)
3.0
4.0
0.348
8.52
11.61
Lead (d)())
0.60
16
0.184
3.26
85.40
Nickel (d)(h)
17
159
0.432
40.20
367.79
NI - WS streams (t)
25
N/A
Silver (d)(h,acute)
0.06
0.36
1.000
0.06
0.36
Zinc (d)(h)
39
40
0.288
136.85
137.94
Beryllium
Arsenic d
ShlrJ�
1.000
6.5
150
65
340
COMMENTS (identify parameters to PERCS Branch to maintain in facility's LIMP/STMP):
ACAH 27.89731
ACCH 27.37303

egei d F= Fathead minnow (Pimphales!Horn ale ). 1=110 Flow (facility isacvuel s=Spirttestbetween Certiled Labs
AZT }o Ztr a0ed
]
%tr"S : w!i �p
al u!S :dwojuoj
/
aa
k
i
ro
- $
0
07
3aa daS unFJew
f
EEE�f^
■
SiOZ/I/6 :wee
agu!S :dwojuoj
is of 4eS!d Im-oil uosP!?0'DOB
ro-
§
p
-n
k
■
}
(
(
1
NJE E �^
2
CL
al2u!S _dwojuoj
0
$
d1MM aR1S41JON-weynna
/
0
\
0
& § )) )
# # f i 4 -1
ki
alu!S=dwo3uoN
/
k
§
Do
ro
ma.
§ 0
0
n m 8nv de!ry qaj
0
b § ) b )
'1
■
\ �
, g _7 F vs
£
$
)
\
§
2
k
agu!S :dwoDuoN
9-98S ornL
0
2
§
\
/
)
ro-
0
01
Daa daS uniJew
Whole Effluent Toxicity Testing and Self Monitoring Summary

Data Summary for Reduced NPDES Permit Monitoring Frequency
Facility name: Mebane Bridge WWTP
Permit number: NC0025071
Data review period: 5/2017 to 5/2020
Approval Criteria:
1. Facility has more than one civil penalty for permit limit violations?
NO
2. Currently under SOC?
NO
3. Facility or employees convicted of CWA violations?
NO
Data Review
Monthly
average limit
Weekly.
average lmit
50% MA
Mean
(geometric
mean for FC)
o ?
< 50 /°.
200%
MA
(BOD5,
TSS,
NH3-
N)
# daily
samples
°
>200%
MA
(BOD5,
TSS, NH3-
<15?
200%
WA
(FC)
# daily
samples
°
>200 /o
WA (FC)
< 20?
(FC)
# of non -
monthly
limit
violations
< 2�
Total Suspended Solids
30
45
15
6.71
OK
60
OK
0
OK
NH3-N (summer)
14.8
35
7.4
0.101
OK 1
29.6
0
OK
0
OK
NH3-N (winter)
47.1
141.3
23.55
0.431
OK
94.2
NA
OK
NA
OK
NH3-N (combined)
28.3 1
79,3 1
2.85
0.199
OK 41
11.4
NA
OK
NA
OK
BOD5 (summer)
30
45
15
F 3.52
OK
60
0
OK
0
OK
BOD5 (winter)
30
45
15
3.72
OK
60
0
OK
0
OK
BOD5 (combined)
30.0 1
45.0 1
15
I 3.60
OK
60
0
OK
0
OK
Fecal Coliform
200/100mL
400/100mL
100
11.20
OK
800 1 I OK
0
OK
I Weighted Average Annual Limit
2 Per DWQ Guidance Regarding the Reduction in Monitoring Frequencies (memo, 10/22/2012), data with seasonal limits must be compared against a weighted average annual limit
Approval Criteria Met:
1) this facility has not received a civil penalty for a permit violation of the target parameters in the last three years
2) Neither the permittee nor any of its employee have been convicted of criminal violation of the CWA within the previous five years
3) This facility is not under an SOC for target parameter effluent limit noncompliance
4) Three year arithmatic mean is less than fifty percent of the monthly average permit limit for BOD5, TSS and NH3-N
5) Three year geometric mean is less than fifty percent of the monthly average permit limit for fecal coliform
6) Less than 15 daily sampling results over the three year review period are in excess of 200% of the monthly average for BOD5, TSS and NH3-N
7) Less than 20 daily sampling results over the three year review period are in excess of 200% of the weekly average for fecal coliform
8) This facility has not received any non -monthly average limit violations in the past year for the four target parameters

Permit No. NC0025071
NPDES Implementation of Instream Dissolved Metals Standards - Freshwater Standards
The NC 2007-2015 Water Quality Standard (WQS) Triennial Review was approved by the NC
Environmental Management Commission (EMC) on November 13, 2014. The US EPA subsequently
approved the WQS revisions on April 6, 2016, with some exceptions. Therefore, metal limits in draft
permits out to public notice after April 6, 2016 must be calculated to protect the new standards - as
approved.
Table 1. NC Dissolved Metals Water Quality Standards/Aquatic Life Protection
Parameter
Acute FW, µg/1
(Dissolved)
Chronic FW, µg/1
(Dissolved)
Acute SW, µg/1
(Dissolved)
Chronic SW, 1.1g/1
(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-[lnhardness](0.041838)} • e^{0.9151 [In hardness]-3.1485}
Cadmium, Acute Trout waters
WER* { 1.136672-[ln hardness](0.041838)} • e^{0.9151 [ln hardness]-3.62361
Cadmium, Chronic
WER* {1.101672-[ln hardness](0.041838)} • e^{0.7998[ln hardness]-4.4451 }
Chromium III, Acute
WER*0.316 • e^{0.8190[ln hardness]+3.7256}
Chromium III, Chronic
WER*0.860 • e^{0.8190[ln hardness]+0.6848}
Copper, Acute
WER*0.960 • e^{0.9422[ln hardness]-1.700}
Copper, Chronic
WER*0.960 • e^{0.8545[ln hardness]-1.702}
Lead, Acute
WER* {1.46203-[ln hardness](0.145712)} • e^{1.273[ln hardness]-1.460}
Lead, Chronic
WER*{1.46203-[ln hardness](0.145712)} • e^{1.273[ln hardness]-4.705}
Nickel, Acute
WER*0.998 • e^{0.8460[ln hardness]+2.255}
Nickel, Chronic
WER*0.997 • e^{0.8460[ln hardness]+0.0584}
Page 1 of 4

Permit No. NC0025071
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 Informatiion on the Reasonable Potential Analysis (RPA)
The RPA process itself did not change as the result of the new metals standards. However, application of
the dissolved and hardness -dependent standards requires additional consideration in order to establish the
numeric standard for each metal of concern of each individual discharge.
The hardness -based standards require some knowledge of the effluent and instream (upstream) hardness
and so must be calculated case -by -case for each discharge.
Metals limits must be expressed as `total recoverable' metals in accordance with 40 CFR 122.45(c). The
discharge -specific standards must be converted to the equivalent total values for use in the RPA
calculations. We will generally rely on default translator values developed for each metal (more on that
below), but it is also possible to consider case -specific translators developed in accordance with
established methodology.
RPA Permitting Guidance/WQBELs for Hardness -Dependent Metals - Freshwater
The RPA is designed to predict the maximum likely effluent concentrations for each metal of concern,
based on recent effluent data, and calculate the allowable effluent concentrations, based on applicable
standards and the critical low -flow values for the receiving stream.
If the maximum predicted value is greater than the maximum allowed value (chronic or acute), the
discharge has reasonable potential to exceed the standard, which warrants a permit limit in most cases. If
monitoring for a particular pollutant indicates that the pollutant is not present (i.e. consistently below
detection level), then the Division may remove the monitoring requirement in the reissued permit.
1. To perform a RPA on the Freshwater hardness -dependent metals the Permit Writer compiles the
following information:
• Critical low flow of the receiving stream, 7Q10 (the spreadsheet automatically calculates
the 1Q10 using the formula 1Q10 = 0.843 (s7Q10, cfs)°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. NC0025071
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 1 Q10 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 =
Ctotal
1
1 + { [Kpo] [Ss(1+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 s7Q10)
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 s7Q1 0 may be incorporated as applicable:
1 Q 10 = used in the equation to protect aquatic life from acute toxicity
Page 3 of 4

Permit No. NC0025071
QA = used in the equation to protect human health through the consumption of water,
fish, and shellfish from carcinogens
30Q2 = used in the equation to protect aesthetic quality
6. The permit writer enters the most recent 2-3 years of effluent data for each pollutant of concern.
Data entered must have been taken within four and one-half years prior to the date of the permit
application (40 CFR 122.21). The RPA spreadsheet estimates the 95th percentile upper
concentration of each pollutant. The Predicted Max concentrations are compared to the Total
allowable concentrations to determine if a permit limit is necessary. If the predicted max exceeds
the acute or chronic Total allowable concentrations, the discharge is considered to show
reasonable potential to violate the water quality standard, and a permit limit (Total allowable
concentration) is included in the permit in accordance with the U.S. EPA Technical Support
Document for Water Quality -Based Toxics Control published in 1991.
7. When appropriate, permit writers develop facility specific compliance schedules in accordance
with the EPA Headquarters Memo dated May 10, 2007 from James Hanlon to Alexis Strauss on
40 CFR 122.47 Compliance Schedule Requirements.
8. The Total Chromium NC WQS was removed and replaced with trivalent chromium and
hexavalent chromium Water Quality Standards. As a cost savings measure, total chromium data
results may be used as a conservative surrogate in cases where there are no analytical results
based on chromium III or VI. In these cases, the projected maximum concentration (95th %) for
total chromium will be compared against water quality standards for chromium III and
chromium VI.
9. Effluent hardness sampling and instream hardness sampling, upstream of the discharge, are
inserted into all permits with facilities monitoring for hardness -dependent metals to ensure the
accuracy of the permit limits and to build a more robust hardness dataset.
10. Hardness and flow values used in the Reasonable Potential Analysis for this permit included:
Parameter
Value
Comments (Data Source)
Average Effluent Hardness (mg/L)
[Total as, CaCO3 or (Ca+Mg)]
69.33
Effluentpollutantscans
Average Upstream Hardness (mg/L)
[Total as, CaCO3 or (Ca+Mg)]
25
Default value
7Q10 summer (cfs)
370.00
Previous fact sheet
1Q10 (cfs)
299.26
RPA calculation
Permitted Flow (MGD)
13.50
Previous permit
Date: August 17, 2020
Permit Writer: Cassidy Kurtz
Page 4 of 4

United States Environmental Protection Agency
E PA Washington, D.C. 20460
Water Compliance Inspection Report
Form Approved.
OMB No. 2040-0057
Approval expires 8-31-98
Section A: National Data System Coding (i.e., PCS)
Transaction Code NPDES yr/mo/day Inspection
1 IN I 2 IL I 3 I NC0025071 111 121 19/09/13 117
Type
1810I
IIIIIIIIIII
Inspector Fac Type
19I S I 2011
21IIIIII IIIIIIIIIIIIIIIIII I IIIIII
P6
Inspection Work Days Facility Self -Monitoring Evaluation Rating B1 QA Reserved
671 I 70I I 711 172 I N I 73I 1 74 71
I I
I I I I I I 180
Section B: Facility Data
Name and Location of Facility Inspected (For Industrial Users discharging to POTW, also include
POTW name and NPDES permit Number)
Mebane Bridge WWTP
204 Mebane Bridge Rd
Eden NC 27288
Entry Time/Date
11:OOAM 19/09/13
Permit Effective Date
15/03/01
Exit Time/Date
01:OOPM 19/09/13
Permit Expiration Date
18/04/30
Name(s) of Onsite Representative(s)/Titles(s)/Phone and Fax Number(s)
///
Melinda Sessoms Ward/ORC/336-627-1009/
Other Facility Data
Name, Address of Responsible Official/Title/Phone and Fax Number
Contacted
Brad Corcoran,PO Box 70 Eden NC 272890070/City
Manager/336-623-2110/3366232726 No
Section C: Areas Evaluated During Inspection (Check only those areas evaluated)
Permit Flow Measurement Operations & Maintenar Records/Reports
Self -Monitoring Progran Sludge Handling DispoFacility Site Review Effluent/Receiving Wate
Laboratory
Section D: Summary of Finding/Comments (Attach additional sheets of narrative and checklists as necessary)
(See attachment summary)
Name(s) and Signature(s) of Inspector(s) Agency/Office/Phone and Fax Numbers Date
Paul DiMatteo DWR/WSRO WQ/336-776-9691/
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# 1

3I
NPDES yr/mo/day
N C 0025071 I11 121 19/09/13
117
Inspection Type
18 [j
1
Section D: Summary of Finding/Comments (Attach additional sheets of narrative and checklists as necessary)
On flow proportional sampling - Permittee should submit a request for timed -based sampling, produce
a letter previously granted by the Division, or set up the system for proper floow proportional sampling.
Note that constant time/constant volume sampling may only be used when the effluent flow rate varies
less than 15%; thus, Permittee should submit daily flow charts with their proposal.
Page# 2

Permit: NC0025071
Inspection Date: 09/13/2019
Owner - Facility: Mebane Bridge WWTP
Inspection Type: Compliance Evaluation
Operations & Maintenance
Is the plant generally clean with acceptable housekeeping?
Does the facility analyze process control parameters, for ex: MLSS, MCRT, Settleable
Solids, pH, DO, Sludge Judge, and other that are applicable?
Comment:
Permit
(If the present permit expires in 6 months or less). Has the permittee submitted a new
application?
Is the facility as described in the permit?
# Are there any special conditions for the permit?
Is access to the plant site restricted to the general public?
Is the inspector granted access to all areas for inspection?
Comment:
Yes No NA NE
• ❑ ❑ ❑
Yes No NA NE
• ❑ ❑ ❑
• ❑ ❑ ❑
• ❑ ❑ ❑
Record Keeping Yes No NA NE
Are records kept and maintained as required by the permit? • ❑ ❑ ❑
Is all required information readily available, complete and current? • ❑ ❑ ❑
Are all records maintained for 3 years (lab. reg. required 5 years)? • ❑ ❑ ❑
Are analytical results consistent with data reported on DMRs? ❑ • ❑ ❑
Is the chain -of -custody complete? • ❑ ❑ ❑
Dates, times and location of sampling •
Name of individual performing the sampling •
Results of analysis and calibration •
Dates of analysis •
Name of person performing analyses •
Transported COCs •
Are DMRs complete: do they include all permit parameters? • ❑ ❑ ❑
Has the facility submitted its annual compliance report to users and DWQ? • ❑ ❑ ❑
(If the facility is = or > 5 MGD permitted flow) Do they operate 24/7 with a certified operatc • El El ❑
on each shift?
Is the ORC visitation log available and current? • ❑ ❑ ❑
Is the ORC certified at grade equal to or higher than the facility classification? • ❑ ❑ ❑
Is the backup operator certified at one grade less or greater than the facility classification' • El ❑ ❑
Is a copy of the current NPDES permit available on site? • El El El
Page# 3

Permit: NC0025071
Inspection Date: 09/13/2019
Owner - Facility: Mebane Bridge WWTP
Inspection Type: Compliance Evaluation
Record Keeping
Facility has copy of previous year's Annual Report on file for review?
Yes No NA NE
Comment: DMR Note - Reviewed the DMR for 9/18/2019 and noted that Effluent Zinc was reported as
kg/day, and not mg/I. No conversion was made, thus this is simply a unit error. The DMRs
with this fault should be corrected and resubmitted. This appears to have been present in
DMRs since 6/2016.
Effluent Pipe
Is right of way to the outfall properly maintained?
Are the receiving water free of foam other than trace amounts and other debris?
If effluent (diffuser pipes are required) are they operating properly?
Yes No NA NE
❑ • ❑ ❑
• ❑ ❑ ❑
❑ ❑ • ❑
Comment: The outfall was not observed due to access issues. The operators said that they tried to get
the lines crew to clear the outfall ROW but due to the time of year it was not directly
accessible.
Flow Measurement - Influent Yes No NA NE
# Is flow meter used for reporting? • El El El
Is flow meter calibrated annually? • ❑ ❑ ❑
Is the flow meter operational? • El El El
(If units are separated) Does the chart recorder match the flow meter? ❑ ❑ ❑ •
Comment:
Flow Measurement - Effluent Yes No NA NE
# Is flow meter used for reporting? ❑ • ❑ ❑
Is flow meter calibrated annually? • ❑ ❑ ❑
Is the flow meter operational? • El El El
(If units are separated) Does the chart recorder match the flow meter? ❑ ❑ • ❑
Comment: Flow meters are installed on the effluent sides of the 3 chlorine contact chambers and they
are calibrated but not connected to SCADA and not used for flow reporting or flow
proportioning. Operators said that they were suspicious of the accuracy of the meters
despite them being calibrated quarterly.
Bar Screens
Type of bar screen
a.Manual
b.Mechanical
Are the bars adequately screening debris?
Yes No NA NE
•
Page# 4

Permit: NC0025071
Inspection Date: 09/13/2019
Owner - Facility: Mebane Bridge WWTP
Inspection Type: Compliance Evaluation
Bar Screens Yes No NA NE
Is the screen free of excessive debris? • ❑ ❑ ❑
Is disposal of screening in compliance? • ❑ ❑ ❑
Is the unit in good condition? • ❑ ❑ ❑
Comment:
Grit Removal
Type of grit removal
a.Manual
b.Mechanical
Is the grit free of excessive organic matter?
Is the grit free of excessive odor?
# Is disposal of grit in compliance?
Comment:
Secondary Clarifier
Is the clarifier free of black and odorous wastewater?
Is the site free of excessive buildup of solids in center well of circular clarifier?
Are weirs level?
Is the site free of weir blockage?
Is the site free of evidence of short-circuiting?
Is scum removal adequate?
Is the site free of excessive floating sludge?
Is the drive unit operational?
Is the return rate acceptable (low turbulence)?
Is the overflow clear of excessive solids/pin floc?
Is the sludge blanket level acceptable? (Approximately'/4 of the sidewall depth)
Yes No NA NE
Yes No NA NE
▪ ❑ ❑ ❑
• ❑ ❑ ❑
• ❑ ❑ ❑
• ❑ ❑ ❑
• ❑ ❑ ❑
• ❑ ❑ ❑
• ❑ ❑ ❑
• ❑ ❑ ❑
• ❑ ❑ ❑
• ❑ ❑ ❑
• ❑ ❑ ❑
Comment: Two of four clarifiers are in service due to low flow. Measured the sludge depth in 1 clarifier
at -1.5 feet.
Aeration Basins Yes No NA NE
Mode of operation Ext. Air
Type of aeration system Surface
Is the basin free of dead spots? • ❑ ❑ ❑
Are surface aerators and mixers operational? • ❑ ❑ ❑
Page# 5

Permit: NC0025071
Inspection Date: 09/13/2019
Owner - Facility: Mebane Bridge WWTP
Inspection Type: Compliance Evaluation
Aeration Basins Yes No NA NE
Are the diffusers operational? ❑ ❑ • ❑
Is the foam the proper color for the treatment process? • ❑ ❑ ❑
Does the foam cover less than 25% of the basin's surface? • El ❑ ❑
Is the DO level acceptable? • ❑ ❑ ❑
Is the DO level acceptable?(1.0 to 3.0 mg/I) • ❑ ❑ ❑
Comment: DO in aeration basin 5.74 according to meter set near the end of the basin. Operators said
they try to keep it above 2. Only one aeration basin is in service. Operations said they
installed "solar bees," a solar -powered mixers that keep the basin in suspension near the
end of the basin. They planned to install more.
Disinfection -Gas
Are cylinders secured adequately?
Are cylinders protected from direct sunlight?
Is there adequate reserve supply of disinfectant?
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?
Does the Stationary Source have more than 2500 Ibs of Chlorine (CAS No. 7782-50-5)?
If yes, then is there a Risk Management Plan on site?
If yes, then what is the EPA twelve digit ID Number? (1000-
If yes, then when was the RMP last updated?
Comment:
Yes No NA NE
• ❑ ❑ ❑
• ❑ ❑ ❑
• ❑ ❑ ❑
▪ El El El
❑ ❑ ❑ •
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? • ❑ ❑ ❑
Comment:
Are the tablets the proper size and type?
Are tablet de -chlorinators operational?
Number of tubes in use?
Comment:
❑ ❑ • ❑
❑ ❑ • ❑
Page# 6

Permit: NC0025071
Inspection Date: 09/13/2019
Owner - Facility: Mebane Bridge WWTP
Inspection Type: Compliance Evaluation
Laboratory
Are field parameters performed by certified personnel or laboratory?
Are all other parameters(excluding field parameters) performed by a certified lab?
# Is the facility using a contract lab?
# Is proper temperature set for sample storage (kept at less than or equal to 6.0 degrees
Celsius)?
Incubator (Fecal Coliform) set to 44.5 degrees Celsius+/- 0.2 degrees?
Incubator (BOD) set to 20.0 degrees Celsius +/- 1.0 degrees?
Yes No NA NE
• ❑ ❑ ❑
• ❑ ❑ ❑
❑ ❑ • ❑
Comment: DO and pH calibration records appeared acceptable. Thermometer calibration also
appeared acceptable.
Influent Sampling
# Is composite sampling flow proportional?
Is sample collected above side streams?
Is proper volume collected?
Is the tubing clean?
# Is proper temperature set for sample storage (kept at less than or equal to 6.0 degrees
Celsius)?
Is sampling performed according to the permit?
Yes No NA NE
• ❑ ❑ ❑
• ❑ ❑ ❑
• ❑ ❑ ❑
Comment: Sample volume is checked by staff 3x/day, was not verified during the inspection. Facility
was not sampling during the inspection.
Effluent Sampling
Is composite sampling flow proportional?
Is sample collected below all treatment units?
Is proper volume collected?
Is the tubing clean?
# Is proper temperature set for sample storage (kept at less than or equal to 6.0 degrees
Celsius)?
Is the facility sampling performed as required by the permit (frequency, sampling type
representative)?
Yes No NA NE
❑ • ❑ ❑
• ❑ ❑ ❑
• ❑ ❑ ❑
• ❑ • ❑
▪ ❑ ❑ ❑
Comment: Sample volume is checked by staff 3x/day, was not verified during the inspection. Facility
was not sampling during the inspection. Operators said they did not perform flow
proportional sampling at the effluent due to difficulty in hooking the influent meter up to the
effluent sampler and because, although they have effluent flow meters on each of the
chlorine contact chambers, they did not believe the readings were accurate.
Upstream / Downstream Sampling Yes No NA NE
Page# 7

Permit: NC0025071
Inspection Date: 09/13/2019
Owner - Facility: Mebane Bridge WWTP
Inspection Type: Compliance Evaluation
Upstream / Downstream Sampling
Is the facility sampling performed as required by the permit (frequency, sampling type, an(
sampling location)?
Comment:
Yes No NA NE
• ❑ ❑ ❑
Page# 8

NC0025071 - PPA data 2015, 2016, 2017
1
2015
2016
2017
Parameter
Sample
Result
Quantitat
ion Level
Sample
Result
Quantitat
ion Level
Sample
Result
Quantitat
ion Level
Units of
Measure
ment
Analytical
Method
Ammonia (as N)
0.1
0.1
0.1
0.1
0.1
0.1
mg/1
EPA350.1
Dissolved oxygen
8.1
0.1
7.3
0.1
8.5
0.1
mg/1
4500-OG
Nitrate/Nitrite
7.9
0.08
9.4
0.06
14
0.1
mg/1
E353.2
Total Kjeldahl nitrogen
0.94
0.5
1.1
0.5
0.97
0.5
mg/1
E351.2
Total Phosphorus
0.33
0.05
0.16
0.05
0.15
0.05
mg/1
E365.1
Total dissolved solids
221
25
225
25
239
25
mg/1
SM2540C
Hardness
53.2
0.66
70.6
0.66
84.2
0.66
mg/1
SM2340B
Chlorine (total residual, TRC)
10
10
10
10
10
10
ug/1
4500-CLG
Oil and grease
5
5
5
5
5
5
mg/1
1664-A
Metals (total recoverable), cyanide
and total phenols
Antimony
0.005
0.005
0.005
0.005
0.005
0.005
mg/1
E200.7
Arsenic
0.01
0.01
0.01
0.01
0.01
0.01
mg/1
E200.7
Beryllium
0.001
0.001
0.001
0.001
0.001
0.001
mg/1
E200.7
Cadmium
0.001
0.001
0.001
0.001
0.001
0.001
mg/1
E200.7
Chromium
0.005
0.005
0.005
0.005
0.005
0.005
mg/1
E200.7
Copper
0.29
0.005
0.011
0.005
0.005
0.005
mg/1
E200.7
Lead
0.005
0.005
0.005
0.005
0.005
0.005
mg/1
E200.7
Mercury
2.23
0.5
1.38
0.5
3.14
0.5
ng/L
E1631E
Nickel
0.005
0.005
0.005
0.005
0.005
0.005
mg/1
E200.7
Selenium
0.01
0.01
0.01
0.01
0.01
0.01
mg/1
E200.7
Silver
0.005
0.005
0.005
0.005
0.005
0.005
mg/1
E200.7
Thallium
0.01
0.01
0.01
0.01
0.01
0.01
mg/1
E200.7
Zinc
0.053
0.01
0.029
0.01
0.05
0.01
mg/1
E200.7
Cyanide
0.008
0.008
0.008
0.008
0.008
0.008
mg/1
SM4500CN-E
Total phenolic compounds
0.01
0.01
0.016
0.01
0.01
0.01
mg/1
E420.4
Volatile organic compounds
Acrolein
5
5
5
5
5
5
ug/1
E624
Acrylonitrile
50
50
50
50
50
50
ug/1
E624
Benzene
2
2
2
2
2
2
ug/1
E624
Bromoform
2
2
2
2
2
2
ug/1
E624
Carbon tetrachloride
2
2
2
2
2
2
ug/1
E624
Chlorobenzene
2
2
2
2
2
2
ug/1
E624
Chlorodibromomethane
3.9
2
2
2
2
2
ug/1
E624
Chloroethane
2
2
2
2
2
2
ug/1
E624
2-chloroethylvinyl ether
5
5
5
5
5
5
ug/1
E624
Chloroform
6.1
2
7
2
4
2
ug/1
E624
Dichlorobromomethane
2
2
3.1
2
2
2
ug/1
E624
1,1-dichloroethane
2
2
2
2
2
2
ug/1
E624
1,2-dichloroethane
2
2
2
2
2
2
ug/1
E624
Trans-1,2-dichloroethylene
2
2
2
2
2
2
ug/1
E624
1,1-dichloroethylene
2
2
2
2
2
2
ug/1
E624
1,2-dichloropropane
2
2
2
2
2
2
ug/1
E624
1,3-dichloropropylene
2
2
2
2
2
2
ug/1
E624
Ethylbenzene
2
2
2
2
2
2
ug/1
E624
Methyl bromide
3.1
2
2
2
2
2
ug/1
E624
Methyl chloride
2
2
2
2
2
2
ug/1
E624
Methylene chloride
2
2
2
2
2
2
ug/1
E624
1,1,2,2-tetrachloroethane
2
2
2
2
2
2
ug/1
E624
Tetrachloroethylene
2
2
2
2
2
2
ug/1
E624
Toluene
2
2
2
2
2
2
ug/1
E624
1,1,1-trichloroethane
2
2
2
2
2
2
ug/1
E624
1,1,2-trichloroethane
2
2
2
2
2
2
ug/1
E624
Trichloroethylene
2
2
2
2
2
2
ug/1
E624
Vinyl chloride
2
2
2
2
2
2
ug/1
E624
Acid -extractable compounds
P-chloro-m-creso
<5
5
5
5
5
5
ug/1
E625

NC0025071 - PPA data 2015, 2016, 2017
2
2-chlorophenol
<5
5
5
5
5
5
ug/1
E625
2,4-dichlorophenol
<5
5
5
5
5
5
ug/1
E625
2,4-dimethylphenol
<10
10
10
10
10
10
ug/1
E625
4,6-dinitro-o-cresol
<20
20
20
20
20
20
ug/1
E625
2,4-dinitrophenol
<50
50
50
50
50
50
ug/1
E625
2-nitrophenol
<5
5
5
5
5
5
ug/1
E625
4-nitrophenol
<50
50
50
50
50
50
ug/1
E625
Pentachlorophenol
<10
10
10
10
25
10
ug/1
E625
Phenol
<5
5
5
5
5
5
ug/1
E625
2,4,6-trichlorophenol
<10
10
10
10
10
10
ug/1
E625
Base -neutral compounds
Acenaphthene
<5
5
5
5
5
5
ug/1
E625
Acenaphthylene
<5
5
5
5
5
5
ug/1
E625
Anthracene
<5
5
5
5
5
5
ug/1
E625
Benzidine
<50
50
50
50
50
50
ug/1
E625
Benzo(a)anthracene
<5
5
5
5
5
5
ug/1
E625
Benzo(a)pyrene
<5
5
5
5
5
5
ug/1
E625
3,4 benzofluoranthene
<5
5
5
5
5
5
ug/1
E625
Benzo(ghi)perylene
<5
5
5
5
5
5
ug/1
E625
Benzo(k)fluoranthene
<5
5
5
5
5
5
ug/1
E625
Bis (2-chloroethoxy) methane
<10
10
10
10
10
10
ug/1
E625
Bis (2-chloroethyl) ether
<5
5
5
5
5
5
ug/1
E625
Bis (2-chloroisopropyl) ether
<5
5
5
5
5
5
ug/1
E625
Bis (2-ethylhexyl) phthalate
<5
5
5
5
5
5
ug/1
E625
4-bromophenyl phenyl ether
<5
5
5
5
5
5
ug/1
E625
Butyl benzyl phthalate
<5
5
5
5
5
5
ug/1
E625
2-chloronaphthalene
<5
5
5
5
5
5
ug/1
E625
4-chlorophenyl phenyl ether
<5
5
5
5
5
5
ug/1
E625
Chrysene
<5
5
5
5
5
5
ug/1
E625
Di-n-butyl phthalate
<5
5
5
5
5
5
ug/1
E625
Di-n-octyl phthalate
<5
5
5
5
5
5
ug/1
E625
Dibenzo(a,h)anthracene
<5
5
5
5
5
5
ug/1
E625
1,2-dichlorobenzene
<2
2
2
2
5
2
ug/1
E625
1,3-dichlorobenzene
<2
2
2
2
5
2
ug/1
E625
1,4-dichlorobenzene
<2
2
2
2
5
2
ug/1
E625
3,3-dichlorobenzidine
<25
25
25
25
25
25
ug/1
E625
Diethyl phthalate
<5
5
5
5
5
5
ug/1
E625
Dimethyl phthalate
<5
5
5
5
5
5
ug/1
E625
2,4-dinitrotoluene
<5
5
I 5.7
5
5
5
ug/1
E625
2,6-dinitrotoluene
<5
5
5
5
5
5
ug/1
E625
1,2-diphenylhydrazine
<5
5
5
5
5
5
ug/1
E625
Fluoranthene
<5
5
5
5
5
5
ug/1
E625
Fluorene
<5
5
5
5
5
5
ug/1
E625
Hexachlorobenzene
<5
5
5
5
5
5
ug/1
E625
Hexachlorobutadiene
<5
5
5
5
5
5
ug/1
E625
Hexachlorocyclo-pentadiene
<10
10
10
10
10
10
ug/1
E625
Hexachloroethane
<5
5
5
5
5
5
ug/1
E625
Indeno(1,2,3-cd)pyrene
<5
5
5
5
5
5
ug/1
E625
Isophorone
<10
10
10
10
10
10
ug/1
E625
Naphthalene
<5
5
5
5
5
5
ug/1
E625
Nitrobenzene
<5
5
5
5
5
5
ug/1
E625
N-nitrosodi-n-propylamine
<5
5
5
5
5
5
ug/1
E625
N-nitrosodimethylamine
<5
5
5
5
5
5
ug/1
E625
N-nitrosodiphenylamine
<10
10
10
10
10
10
ug/1
E625
Phenanthrene
<5
5
5
5
5
5
ug/1
E625
Pyrene
<5
5
5
5
5
5
ug/1
E625
1,2,4,-trichlorobenzene
<5
5
5
5
5
5
ug/1
E625