NC0041483_Fact Sheet 24Aug2021_20210824

NCDEQ
FACT SHEET FOR RENEWAL
NPDES PERMIT NC0041483
Table 1 - Facility Information
Applicant / Facility Name:
Steve Davis / Sunrise Park WWTP
Applicant Address:
P.O Box 2153, Asheboro 27214
Facility Address:
5625 Newman Davis Road, Greensboro
Permitted Flow:
0.003 MGD
Type of Waste / Treatment
Summary:
100% Domestic
no WET test / UV disinfection
Facility / Permit Status:
Biological Grade I WPCS / Renewal
County:
Gilford County
Miscellaneous
Receiving Stream:
UT to Hickory
Creek
Regional Office:
Winston-Salem (WSRO)
Stream Class /
Stream Index:
WS-IV; CA; * /
17-8-8.5-(3)
USGS Quad:
Pleasant Garden, NC
Instream Monitoring:
No
Permittee
Contacts:
Jessica Mize 704-977-0982
[Signature authority]
303(d) Listed?
No
Permit Writer:
Joe R. Corporon, P.G.
Basin:
Cape Fear
Date:
23Aug2021
Subbasin:
03-06-08
Lat. 35° 58' 22"N
HUC:
03030003
Drainage Area (mi2):
s7Q10 (cfs)
0.0
w7Q10 (cfs)
0.0
Average Flow (cfs):
0.0
Long. 79° 50' 19" W
IWC (%):
100%
FACILITY SUMMARY
Sunrise Park WWTP services a 100% domestic wastewater discharge generated by — 11 residences. The
treatment system design flow is 0.003 MGD, currently permitted at this capacity (see discharge data
summary, Table 3).
INSPECTION / CORRESPONDENCE
BIMS records last inspection on 23Feb2018. At that time, WSRO recommended that the poor
condition of the sand filter warranted rebuilding and replacement with new sand.
Sunrise Park MHP WWTP — Renewal Fact sheet
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COMPLIANCE HISTORY - Table 2
L-
2
3
4
5
6
7
a
9
B„ E F J K
ACILITI MONTH YEAR LOCATION PARAMETER UNITS LIMIT
Sunrise
Sunrise
Sunrise
Sunrise
Sunrise
Sunrise
Sunrise
Sunrise
Sunrise
5 2020
5 2020
11 2020
1 2019
1 2019
2 2019
3 2019
7 2019
7 2019
Effluent
Effluent
Effluent
Effluent
Effluent
Effluent
Effluent
Effluent
Effluent
Oxygen, Dissolved (DO)
Temperature
Coliform, Fecal MF
Oxygen, Dissolved (DO)
Temperature
Coliform, Fecal MF
Coliform, Fecal MF
Coliform, Fecal MF
Coliform, Fecal MF
mg/I
deg c
#1100m1
mg/I
deg c
#1100m1
#1100m1
#1100m1
#1100m1
N 1 O 1 Pi Q
CALC
VALUE
R
% OVER VIOL TYPE
S I T
VIOL VIOL LAST UPDATE
ACTION COMMENT
Frequency Violati Proceed to NOD
Frequency Violati Proceed to NOD
400 2420 505 Daily Maximum E Proceed to NOV
Frequency Violati No Action, BF Holiday
Frequency Violati No Action, BF Holiday
400 613 53 Daily Maximum E Proceed to NOV
400 2420 505 Daily Maximum E Proceed to NOV
200 941 371 Monthly Geometr Enforcement Case
400 2420 505 Daily Maximum E Enforcement Case
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jennifer.graznak
INSTREAM MONITORING — not impaired:
Hickory Creek (17-8-8.5-(3) - Supporting; Good -Fair Bioclassification. Currently no stream Monitoring —
low permitted flow; considerable distance to named stream; no changes recommended.
DMR DATA SUMMARY (JAN2018-JUN2021)
Table 3 - Conventional Parameters:
Effluent Characteristics
Minimum
Average
Maximum
Sample Count
Flow (MGD)
0.0004
0.00086
0.0014
1250
BOD, 5-day, 20° C (mg/1)
< 2
2.31
8.3
84
pH (standard units)
6.3
6.5
6.7
90
Temperature ° C [Effluent]
2
15.7
29
183
Total Suspended Solids (mg/1)
2.5
6.22
33.8
174
Fecal Coliform (per 100 ml)
1
101.7
2420
84
Dissolved Oxygen [Effluent]
6.2
8.03
10.1
182
Ammonia (NH3 as N) Eff
0.1
0.4
10.2
85
SUMMARY OF PROPOSED CHANGES
• updated permit format
• added to Class WW-1 citation [section A. (1.) header]
• updated eDMR requirements
• updated site map
PROPOSED SCHEDULE OF ISSUANCE
Draft Permit to Public Notice:
Permit Scheduled to Issue:
Effective Date
August 24, 2021 (est.)
September 30, 2021 (est.)
November 1, 2021 (est.)
Sunrise Park MHP WWTP — Renewal Fact sheet
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NPDES DIVISION CONTACT
If you have questions about any of the above information, or on the attached permit, please email Joe R.
Corporon, P.G. [[e-mail]].
NAME:
t(11
l
DATE: 24AuG2021
NPDESfnplementa on 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 5. NC Dissolved Metals Water Quality Standards/Aquatic Life Protection
Parameter
Acute FW, µg/1
(Dissolved)
Chronic FW,
1.1g/1
(Dissolved)
Acute SW, µg/1
(Dissolved)
Chronic SW,
µg/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 41 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
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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/1
Cadmium, Acute
WER* {1.136672-[ln hardness](0.041838)} • e^{0.9151 [ln
hardness]-3.1485 }
Cadmium, Acute Trout
waters
WER* {1.136672-[ln hardness](0.041838)} • e^{0.9151[In
hardness]-3.6236 }
Cadmium, Chronic
WER*{1.101672-[ln hardness](0.041838)} • e^{0.7998[ln
hardness]-4.4451 }
Chromium III, Acute
WER*0.316 • e^{0.8190[ln hardness]+3.7256}
Chromium III, Chronic
WER*0.860 • e^{0.8190[In hardness]+0.6848}
Copper, Acute
WER*0.960 • e^{0.9422[ln hardness]-1.700}
Copper, Chronic
WER*0.960 • e^{0.8545[In hardness]-1.702}
Lead, Acute
WER* {1.46203 -[ln hardness](0.145712)} • e^ {1.273 [ln hardness]-
1.460 }
Lead, Chronic
WER* {1.46203-[lnhardness](0.145712)} • e^{1.273[In hardness]-
4.705 }
Nickel, Acute
WER*0.998 • e^{0.8460[ln hardness]+2.255}
Nickel, Chronic
WER*0.997 • e^{0.8460[In hardness]+0.0584}
Silver, Acute
WER*0.85 • e^{1.72[In 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.
Sunrise Park MHP WWTP - Renewal Fact sheet
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RPA Permitting Guidance/WQBELs for Hardness -Dependent Metals - Freshwater
The RPA is designed to predict the maximum likely effluent concentrations for each metal of
concern, based on recent effluent data, and calculate the allowable effluent concentrations, based
on applicable standards and the critical low -flow values for the receiving stream.
If the maximum predicted value is greater than the maximum allowed value (chronic or acute),
the discharge has reasonable potential to exceed the standard, which warrants a permit limit in
most cases. If monitoring for a particular pollutant indicates that the pollutant is not present (i.e.
consistently below detection level), then the Division may remove the monitoring requirement in
the reissued permit.
1. To perform a RPA on the Freshwater hardness -dependent metals the Permit Writer
compiles the following information:
• Critical low flow of the receiving stream, 7Q10 (the spreadsheet automatically
calculates the 1Q10 using the formula 1Q10 = 0.843 (s7Q10, cfs) 0.993
• Effluent hardness and upstream hardness, site -specific data is preferred
• Permitted flow
• Receiving stream classification
2. In order to establish the numeric standard for each hardness -dependent metal of concern
and for each individual discharge, the Permit Writer must first determine what effluent
and instream (upstream) hardness values to use in the equations.
The permit writer reviews DMR's, Effluent Pollutant Scans, and Toxicity Test results for
any hardness data and contacts the Permittee to see if any additional data is available for
instream hardness values, upstream of the discharge.
If no hardness data is available, the permit writer may choose to do an initial evaluation
using a default hardness of 25 mg/L (CaCO3 or (Ca + Mg)). Minimum and maximum
limits on the hardness value used for water quality calculations are 25 mg/L and 400
mg/L, respectively.
If the use of a default hardness value results in a hardness -dependent metal showing
reasonable potential, the permit writer contacts the Permittee and requests 5 site -specific
effluent and upstream hardness samples over a period of one week. The RPA is rerun
using the new data.
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) x (s7Q10, cfs *Avg. Upstream Hardness,
mg/L)
(Permitted Flow, cfs + s7Q10, cfs)
The Combined Hardness for acute is the same but the calculation uses the 1Q10 flow.
3. The permit writer converts the numeric standard for each metal of concern to a total
recoverable metal, using the EPA Default Partition Coefficients (DPCs) or site -specific
translators, if any have been developed using federally approved methodology.
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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:
Cahss = 1
Ctotal 1 + { [Kpo] [ss(l+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
4. The numeric standard for each metal of concern is divided by the default partition
coefficient (or site -specific translator) to obtain a Total Recoverable Metal at ambient
conditions.
In some cases, where an EPA default partition coefficient translator does not exist (ie.
silver), the dissolved numeric standard for each metal of concern is divided by the EPA
conversion factor to obtain a Total Recoverable Metal at ambient conditions. This
method presumes that the metal is dissolved to the same extent as it was during EPA's
criteria development for metals. For more information on conversion factors see the June,
1996 EPA Translator Guidance Document.
5. The RPA spreadsheet uses a mass balance equation to determine the total allowable
concentration (permit limits) for each pollutant using the following equation:
Ca = (s7Q10 + Qw) (Cwqs) — (s7Q10) (Cb)
Qw
Where: Ca = allowable effluent concentration (µg/L or mg/L)
Cwqs = NC Water Quality Standard or federal criteria (µg/L or mg/L)
Cb = background concentration: assume zero for all toxicants exceptNH3* (µg/L or
mg/L)
Qw = permitted effluent flow (cfs, match s7Q 10)
s7Q10 = summer low flow used to protect aquatic life from chronic toxicity and
human health through the consumption of water, fish, and shellfish from
noncarcinogens (cfs)
* Discussions are on -going with EPA on how best to address background
concentrations
Flows other than s7Q10 maybe incorporated as applicable:
1 Q 10 = used in the equation to protect aquatic life from acute toxicity
QA = used in the equation to protect human health through the consumption of
water, fish, and shellfish from carcinogens
30Q2 =used in the equation to protect aesthetic quality
Sunrise Park MHP WWTP — Renewal Fact sheet
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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)]
N/A
Average Upstream Hardness (mg/L)
[Total as, CaCO3 or (Ca+Mg)]
N/A
7Q10 summer(cfs)
N/A
1 Q 10 (cfs)
N/A
Permitted Flow (MGD)
0.003
BIMS
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