NC0082970_Fact Sheet_20220606

Fact Sheet
Renewal 2022 -- NPDES Permit NC0082970
Page 1

DEQ / DWR / NPDES
EXPEDITED FACT SHEET - NPDES PERMIT RENEWAL
NPDES Permit NC0082970
Joe R. Corporon, P.G., Compliance & Expedited Permitting Unit 06Jun2022
Facility Information
Applicant/Facility Name CTI of North Carolina, Inc.
CTI of North Carolina, Inc. – Wilmington Terminal
Applicant Address P.O. Box 576, Savannah, GA 31402
Facility Address 1002 S. Front Street, Wilmington, NC 28401
Facility Contacts Tom Dolan, Environmental Manager / 910-762-2271
Operator of Record: [[e-mail]]
T. Pratt Summers, V.P Operations, [[e-mail]]
Mailing address: 1002 S Front Street, Wilmington
Permitted Flow (MGD) not limited
Type of Waste 100% Industrial; stormwater and remediated groundwater in
proximity to fuel bulk surface storage exceeding 1.0 million gallons
Facility Class PC-1 County New Hanover
Permit Status Renewal Regional Office WiRO
Stream Characteristics
Receiving Stream Cape Fear River Stream Classification SC (PNA)
Stream Segment [18-(71)] Drainage basin Cape Fear
Summer 7Q10 (cfs) 600 Subbasin
[HUC]
03-06-17
[HUC: 030300050503]
Winter 7Q10 (cfs) Tidal Use Support Impaired for aquatic
life 30Q2 (cfs) Tidal 303(d) Listed
Average Flow (cfs) Tidal State Grid K27NW
IWC (%) 0.05% (001 & 003) USGS Topo Quad Wilmington, NC
Facility Summary:
CTI of North Carolina - Wilmington Terminal (herein CTI) is a hydrocarbon fuel, surface bulk-storage
facility, a 100% industrial, minor discharger [flow <1 MGD]. The permit renewal application for this
Surface Water Pollution Control Program states that the Permittee has “…made no significant changes to
the treatment systems…” since last renewal. This discharge combines stormwater and treated groundwater
found in proximity to aboveground storage tanks (ASTs). Because surface bulk storage exceeds one million
gallons, treated effluents do NOT qualify for the Division’s Stormwater Permit. Currently active point-
source facilities are described as:
• Both Outfalls 001 & 003 - treatment systems consisting of
o gravity-type oil/water separator
o mechanical skimmers
o waste-product holding/storage tanks
• Outfall 001 ONLY - a groundwater remediation system [design flow 0.014 MGD, no
permit limit]; this discharge combines stormwater and remediation wastewater utilizing
o an oil/water separator
o air stripper
o particulate filters
o activated carbon
Fact Sheet
Renewal May2022 -- NPDES NC0082970
Page 2
Summary of Changes for Renewal:
1. updated permit text and Site Map
2. renewal continues to require test methods EPA 624/625, hereby updated to
624.1 and 625.1 with revised text [see section A. (1.) and related Special
Condition Additional Monitoring and Reporting Requirements A. (7.)]
providing for eDMR reporting of any analyte detected.
3. discontinued monitoring for Total Suspended Solids (TSS) because the
receiving stream is not impaired for TSS
4. revised Turbidity units from 25 NTU to 50 NTU because the receiving
steam is classified SC, and it is not impaired for Turbidity
5. deleted previous Footnote 6. [Sections A. (1.) and A. (2.)] addressing
Naphthalene (no longer applicable)
6. added pH monitoring to both outfalls [required by EPA of industrial permits].
7. corrected Oil & Grease (O&G) parameter code from 00556 to 00552 [EPA
method 1664 (SGT-HEM) intended to target petroleum hydrocarbon
products rather than soaps/fats]
8. Outfall 001 Only - Whole Effluent Toxicity (WET) testing -- DWR hereby
replaces Acute TAE6C with saltwater Chronic EPA Method 1007.0 Mysid
shrimp, P/F Permit Limited (see Rationale below).
Rationale for Chronic (WET) Testing at Outfall 001:
1. CTI combines remediated groundwater and stormwater discharging continuously at Outfall 001.
DWR must therefore define this effluent as chemically complex. Complex wastestreams with
continuous flow require Chronic WET testing [see Director’s Memo – Colene Sullins, 1999].
2. DWR evaluates WET using aquatic test species and the flow ratio of effluent vs. the
receiving stream, or the instream waste concentration (IWC) expressed as a percentage.
However, CTI discharges to SC waters (influenced by ocean tides - no evident 7Q10 stream
flow) where the IWC has not been quantified and may not be quantified without CTI’s further
study.
3. Assigning an alternate WET test method to such effluents may require a dilution study. Upon
request, CTI may initiate this study to establish alternate test species considering saltwater vs.
freshwater if this study is performed in accord with methods establish by the Division
[Director’s Memo – Colene Sullins, 1999].
4. Therefore, until the Permittee may request approval for further study, DWR hereby replaces
acute WET test TAE6C with Chronic WET test EPA Method 1007.0 - Mysid Shrimp
(Mysidopsis bahia), Pass/Fail, permit limited for saltwater, to be performed at 90% effluent
concentration, monitored Quarterly [see permit section A. (1.) and A. (5.)].
Impaired Receiving Stream: The receiving-stream segment [18-(71)a3] is listed Impaired for aquatic life,
2020 Integrated Report 303(d) list.
Monitoring for BOD5 and Methanol: The renewal application reports Methanol detected in 3 instances
during the previous permit cycle. In two of these reports, BOD5 was also elevated. The Permittee perceives
this to indicate organic concentrations related to Methanol, therefore the Permittee requests that monitoring
of BOD5 continue. Considering that Methanol has no surface water quality standard, DWR has no objection
to renewing the Permittee’s request.
Fact Sheet
Renewal May2022 -- NPDES NC0082970
Page 3

DMR Parameter Data - Review and Summary (Jan 2018 – Feb2022)

Outfall 001

Parameter Max Min Average Count Units

00556 - Oil & Grease 8 5 5 106 mg/l

CO310 - BOD 5-day 36 2 5.94 52 mg/l
77885 - Methanol 12.9 5 5.45 52
EPA Method 624 Not reported
EPA Method 625 Parameter(s) detected
22417 - Methyl Tert-Butyl Ether (MTBE) 2.0 <0.5 0.59 21 ug/l

34010 - Toluene 2.0 <0.5 0.53 53 ug/l

34030 - Benzene 2.0 <0.5 0.53 53 ug/l

34371 - Ethylbenzene 2.0 <0.5 0.83 53 ug/l

34696 - Naphthalene 2.0 0.5 0.59 22 ug/l

81551 - Xylene (mix of m+o+p) 6.0 0.5 1.63 53 ug/l

CO530 - Solids, Total Suspended (TSS) 50.6 2.5 12.1 52 mg/l
00070 - Turbidity 101 3.5 22.56 62 NTU
TGE3E - Acute WET (Quarterly) 4 = fail Last fail
Feb2020 14
Outfall 003

Parameter Max Min Average Count Units

00556 - Oil & Grease 7.5 <5 5.1 55 mg/L

34030 - Benzene 24 <0.5 5.39 14 ug/L

34696 - Naphthalene 1.5 0.5 0.91 9 ug/L

81551 - Xylene (mix of m+o+p) 1.5 1.41 1.49 9 ug/L

CO530 - Solids, Total Suspended TSS 25.6 2.5 11.84 52 mg/L

00070 - Turbidity 61.9 3.7 18.52 60 NTU
51518 – EPA 624 Parameter(s) detected
22417 - MTBE 0.9 One test only 1 mg/L
TGE3E - Acute WET (Annually) All “Pass” 2018-2022 5
Outfall 001 - Annual Flow Summary: Data (MGD)
Parameter Year Max Min Average Count
50050 - Flow, in conduit or thru treatment plant 2018 0.279 0.002 0.042 60
2019 0.117 0.002 0.012 60
2020 0.032 0.001 0.018 65
2021 0.202 0.001 0.014 65
2022 0.015 0.001 0.0126 15
Flow - Max year 2018 0.279

Outfall 003 - Annual Flow Summary: Data (MGD)
Parameter Year Max Min Average Count
50050 - Flow, in conduit or thru treatment plant 2018 0.224 0.001 0.031 60
2019 0.085 0.003 0.016 60
2020 0.099 0.002 0.026 62
2021 0.133 0.001 0.020 63
2022 0.360 0.003 0.033 15
Flow - Max year 2022 0.360
Fact Sheet
Renewal May2022 -- NPDES NC0082970
Page 4

Compliance History: By Outfall Dec2019 to Feb2022.

Active Outfall Coordinates - Outfalls 001 & 003 (no changes recommended).
Outfall 001 34º 13’ 16”, -77º 57’ 03” [34.2211, -77.9508]
Outfall 003 34º 13’ 20”, -77º 57’ 04” [34.2222, -77.9511]

Aerial Photo of Active Outfalls 001 and 003

Fact Sheet
Renewal May2022 -- NPDES NC0082970
Page 5

PROPOSED SCHEDULE FOR PERMIT ISSUANCE

Draft Permit to Public Notice [estimated]: May 23, 2022
Permit Scheduled to Issue [estimated]: July 01, 2022
Effective Date [estimated] August 01, 2022

NPDES UNIT CONTACT

If you have questions regarding any of the above information or on the attached permit, please
contact Joe Corporon [[e-mail]].

NAME: DATE: 06JUN2022

NPDES Implementation of Instream Dissolved Metals Standards – Freshwater

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 Notes:
1. FW= Freshwater, SW= Saltwater
2. Calculation = Hardness dependent standard
3. Only the aquatic life standards listed above are expressed in dissolved form. Aquatic life standards
for Mercury and selenium are still expressed as Total Recoverable Metals due to bioaccumulative
concerns (as are all human health standards for all metals). It is still necessary to evaluate total
recoverable aquatic life and human health standards listed in 15A NCAC 2B.0200 (e.g., arsenic at
10 µg/l for human health protection; cyanide at 5 µg/L and fluoride at 1.8 mg/L for aquatic life
protection).

Table 2. Dissolved Freshwater Standards for Hardness-Dependent Metals
The Water Effects Ratio (WER) is equal to one unless determined otherwise under 15A NCAC
02B .0211 Subparagraph (11)(d)

Metal NC Dissolved Standard, µg/l
Cadmium, Acute WER*{1.136672-[ln hardness](0.041838)} ∙ e^{0.9151 [ln hardness]-3.1485}
Cadmium, Acute
Trout waters
WER*{1.136672-[ln hardness](0.041838)} ∙ e^{0.9151[ln hardness]-3.6236}
Cadmium, Chronic WER*{1.101672-[ln hardness](0.041838)} ∙ e^{0.7998[ln hardness]-4.4451}
Chromium III, Acute WER*0.316 ∙ e^{0.8190[ln hardness]+3.7256}
Chromium III, Chronic WER*0.860 ∙ e^{0.8190[ln hardness]+0.6848}
Copper, Acute WER*0.960 ∙ e^{0.9422[ln hardness]-1.700}
Fact Sheet
Renewal May2022 -- NPDES NC0082970
Page 6
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}
Silver, Acute WER*0.85 ∙ e^{1.72[ln hardness]-6.59}
Silver, Chronic Not applicable
Zinc, Acute WER*0.978 ∙ e^{0.8473[ln hardness]+0.884}
Zinc, Chronic WER*0.986 ∙ e^{0.8473[ln hardness]+0.884}

General Information on the Reasonable Potential Analysis (RPA)

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

RPA Permitting Guidance/WQBELs for Hardness-Dependent Metals - Freshwater

The RPA is designed to predict the maximum likely effluent concentrations for each metal of concern,
based on recent effluent data, and calculate the allowable effluent concentrations, based on applicable
standards and the critical low-flow values for the receiving stream.

If the maximum predicted value is greater than the maximum allowed value (chronic or acute), the
discharge has reasonable potential to exceed the standard, which warrants a permit limit in most cases. If
monitoring for a particular pollutant indicates that the pollutant is not present (i.e. consistently below
detection level), then the Division may remove the monitoring requirement in the reissued permit.

1. To perform a RPA on the Freshwater hardness-dependent metals the Permit Writer compiles the
following information:
• Critical low flow of the receiving stream, 7Q10 (the spreadsheet automatically calculates
the 1Q10 using the formula 1Q10 = 0.843 (s7Q10, cfs) 0.993
• Effluent hardness and upstream hardness, site-specific data is preferred
• Permitted flow
• Receiving stream classification

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

The permit writer reviews DMR’s, Effluent Pollutant Scans, and Toxicity Test results for any
hardness data and contacts the Permittee to see if any additional data is available for instream
hardness values, upstream of the discharge.
Fact Sheet
Renewal May2022 -- NPDES NC0082970
Page 7

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.

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 (i.e. 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.
EPA default partition coefficients or the “Fraction Dissolved” converts the value for
dissolved metal at laboratory conditions to total recoverable metal at in-stream ambient
conditions. This factor is calculated using the linear partition coefficients found in The
Metals Translator: Guidance for Calculating a Total Recoverable Permit Limit from a
Dissolved Criterion (EPA 823-B-96-007, June 1996) and the equation:

_Cdiss__ = _______1_______________
Ctotal 1 + { [Kpo] [ss(1+a)] [10-6] }

Where:
ss = in-stream suspended solids concentration [mg/l], minimum of 10 mg/L used, and
Kpo and a = constants that express the equilibrium relationship between dissolved and
adsorbed forms of metals. A list of constants used for each hardness-dependent metal can
also be found in the RPA program under a sheet labeled DPCs.

Fact Sheet
Renewal May2022 -- NPDES NC0082970
Page 8

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

Ca = (s7Q10 + Qw) (Cwqs) – (s7Q10) (Cb)
Qw
Where: Ca = allowable effluent concentration (µg/L or mg/L)
Cwqs = NC Water Quality Standard or federal criteria (µg/L or mg/L)
Cb = background concentration: assume zero for all toxicants except NH3* (µg/L or mg/L)
Qw = permitted effluent flow (cfs, match s7Q10)
s7Q10 = summer low flow used to protect aquatic life from chronic toxicity and
human health through the consumption of water, fish, and shellfish from
noncarcinogens (cfs)
* Discussions are on-going with EPA on how best to address background
concentrations

Flows other than s7Q10 may be incorporated as applicable:
1Q10 = used in the equation to protect aquatic life from acute toxicity
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.
Fact Sheet
Renewal May2022 -- NPDES NC0082970
Page 9

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.
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)]
~ No Metals; monitoring not required
Average Upstream Hardness (mg/L)
[Total as, CaCO3 or (Ca + Mg)]
~ No Metals; monitoring not required
7Q10 summer (cfs) 0.0 IWC = (?) under tidal conditions
1Q10 (cfs) 0.0 IWC = (?) under tidal conditions
Permitted Flow (MGD) ~ BIMS:
Highest monthly average 001 = 0.095 MGD.
Highest monthly average 003 = 0.360 MGD.