NC0089451_Fact Sheet_20240903

FACT SHEET
COMPLEX EXPEDITED - PERMIT RENEWAL
DEQ / DWR / NPDES Permit NCO089451
Joe R. Corporon, P.G., Compliance and Expedited Permitting - 03Sep2024
Table 1-- Facility Information
Applicant/Facility Name
Addis Gates Company, Inc. GW-REM [former Cates Brinery]
Applicant Address
P.O. Box 146, Parkton 28371-0146
Facility Address
2640 McIver Road, Parkton, 28371
Contact:
John B. Cates, President 'ohn addiscates.com ; 910-237-5111
Permitted Flow (MGD)
0.025
Type of Waste
Sodium Chloride(NaCl)plus metals
Facility Class
Physical/Chemical, Class 1
GW-REM for Chloride
County
Robeson
Permit Status
Renewal
Regional Office
FRO
Receiving -Stream Characteristics
Receiving Stream
Dunn's Marsh
(Hughes Mill Pond)
Stream
Classification
C; SW
Stream SegLnent
14-22-1-3-2
Drainage basin
Lumber
Summer 7Q10 (cfs)
0.0
Subbasin /
HUC
03-07-53 /
0304020306
Winter 7Q10 (cfs)
0.0
Use Support
Yes
30Q2 (cfs)
0.0
303(d) Listed
Yes [Lumber River
Mercury fish advisory]
Average Flow (cfs)
0.0
State Grid
H22NE
IWC (%)
100 (?)
USGS Topo Quad
Parkton, NC
Facility History / GW-REM Treatment Objectives. Addis Cates Company, Inc. (Cates or the Permittee)
operated a cucumber brinery from —1960 to —1990. Directed by the NC Division of Environmental
Management Cates implemented a groundwater remediation (GW-REM) certified May 22, 1986, to address an
aquifer impacted with sodium chloride exceeding groundwater standards (NaCI to levels — 4,000 mg/L).
Cate's application for surface discharge prompted a need to address groundwater contamination spreading
offsite. The Applicant's EAA proposed to dilute contaminated groundwater with clean groundwater. Although
subsurface injection is not permitted in North Carolina, the Division agreed on the viability of that the
proposed discharge alternatives.
Discharge/treatment alternatives included 20-year present -value cost estimates. The EAA concluded that the
more economically viable options (#6 and #7) show estimated costs within 5%.
Summary of Engineering Alternatives Analysis (EAA) — Seven (7) Alternatives
1. Discharge to Sanitary Sewer
2. Land Application
3. Reuse and Brine Reject Evaporated Onsite
4. Reuse with Brine Reject Disposal Offsite
5. Reuse with Brine Reject Treated Onsite by Thermo -Ionic Process
6. Direct Discharge Diluted with Surface Water
7. Direct Discharge Diluted with Groundwater
The target aquatic life action level for NaCl is 230 mg/L. Cates proposed to pump and treat local, fresh
groundwater at a rate of 0.025 MGD. A dilution ratio of 20 to 1 was deemed satisfactory to meet surface
water -quality standards (SWQS).
Fact Sheet
New Permit -- NPDES Permit NCO089451
Page 1

Parameters of Concern (POCs). Treatment addresses POCs detected in wells at levels above respective
SWQS (Table 2). Monitoring of the effluent during the previous permit cycle included the parameters Total
Chloride and the metals Total mercury, Total Selenium, and Total Silver (see Table 2). For renewal, based
on the applied reasonable potential analyses (RPA), the Division will require monitoring of and limits for
Total Copper, Total Chloride, Total Mercury and Total Silver, based on their potential to exceed surface
water quality standards (SWQS).
This effluent does not contain oxygen -consuming wastes or suspended solids. The Division will discontinue
monitoring for Turbidity as the receiving stream is not impaired for Turbidity.
Whole Effluent Toxicity (WET) Testing — This permit continues to require Acute, WET testing (Quarterly)
using Fathead Minnow (Pimephalespromelas), 24-hr definitive, LC-50>100% [method TAE6C]. No changes
recommended.
COMPLIANCE HISTORY
BIMS SHOWS NO VIOLATIONS.
PROPOSED SCHEDULE FOR PERMIT ISSUANCE
Draft Permit to Public Notice:
Submit for final signature [estimated]:
Permit Issue [estimated]:
Effective Date [estimated]:
NPDES DIVISION CONTACT
September 03, 2024
October 10, 2024
October 25, 2024
December 1, 2024
If you have questions about any of the above information, or about the attached permit, please email
Joe R. Corporon, P.G. [e-mail]].
NAME
DATE: 03SEP2024
Fact Sheet
Permit Renewal 2024 -- NPDES NCO089451
Page 2

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 April6, 2016 must
be calculated to protect the new standards - as approved.
Table 1. NC Dissolved Metals Water Quality Standards/Aquatic Life Protection
Parameter
Acute FW, µg/l
(Dissolved)
Chronic FW, µg/l
(Dissolved)
Acute SW, µg/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. Calculatiol = 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 213.0200 (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, 1
Cadmium, Acute
WER*{1.136672-[ln hardness](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]-3.6236}
Cadmium, Chronic
WER*{1.101672-[ln hardness](0.041838)} • e^{0.7998[ln hardness]-4.4451}
Chromium III, Acute
WER*0.316 e"{0.8190[ln hardness]+3.7256}
Chromium III, Chronic
WER*0.860 e"{0.8190[ln hardness]+0.6848}
Copper, Acute
WER*0.960 e^{0.9422[ln hardness]-1.700}
Copper, Chronic
WER*0.960 e^{0.8545[ln hardness]-1.7021
Lead, Acute
WER*{1.46203-[1n hardness](0.145712)1 • e^{1.273[ln hardness]-1.460}
Lead, Chronic
WER*{1.46203-[1n hardness](0.145712)1 • 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[In hardness]+0.8841
Fact Sheet
Permit Renewal 2024 -- NPDES NC0089451
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Zinc, Chronic WER*0.986 • e^{0.8473[ln hardness]+0.884)
General Information on the Reasonable Potential Analysis (RPA)
The RPA process itself did not change as the result of the new metals standards. However,
application of the dissolved and hardness -dependent standards requires additional consideration in
order to establish the numeric standard for each metal of concern of each individual discharge.
The hardness -based standards require some knowledge of the effluent and instream (upstream)
hardness and so must be calculated case -by -case for each discharge.
Metals limits must be expressed as `total recoverable' metals in accordance with 40 CFR 122.45(c).
The discharge -specific standards must be converted to the equivalent total values for use in the RPA
calculations. We will generally rely on default translator values developed for each metal (more on
that below), but it is also possible to consider case -specific translators developed in accordance with
established methodology.
RPA Permitting Guidance/WOBELs for Hardness -Dependent Metals - Freshwater
The RPA is designed to predict the maximum likely effluent concentrations for each metal of concern, based on recent
effluent data, and calculate the allowable effluent concentrations, based on applicable standards and the critical low -flow
values for the receiving stream.
If the maximum predicted value is greater than the maximum allowed value (chronic or acute), the
discharge has reasonable potential to exceed the standard, which warrants a permit limit in most
cases. If monitoring for a particular pollutant indicates that the pollutant is not present (i.e.
consistently below detection level), then the Division may remove the monitoring requirement in the
reissued permit.
1. To perform a RPA on the Freshwater hardness -dependent metals the Permit Writer compiles
the following information:
• Critical low flow of the receiving stream, 7Q10 (the spreadsheet automatically
calculates the 1 Q 10 using the formula 1 Q 10 = 0.843 (s7Q 10, cfs) 0.993
• Effluent hardness and upstream hardness, site -specific data is preferred
• Permitted flow
• Receiving stream classification
2. In order to establish the numeric standard for each hardness -dependent metal of concern and
for each individual discharge, the Permit Writer must first determine what effluent and
instream (upstream) hardness values to use in the equations.
The permit writer reviews DMR's, Effluent Pollutant Scans, and Toxicity Test results for any
hardness data and contacts the Permittee to see if any additional data is available for instream
hardness values, upstream of the discharge.
If no hardness data is available, the permit writer may choose to do an initial evaluation using
a default hardness of 25 mg/L (CaCO3 or (Ca + Mg)). Minimum and maximum limits on the
hardness value used for water quality calculations are 25 mg/L and 400 mg/L, respectively.
Fact Sheet
Permit Renewal 2024 -- NPDES NCO089451
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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 (s7Q 10, 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:
Caiss — 1
Ctotal 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 NH 3 * (µg/L or mg/L)
Qw =permitted effluent flow (cfs, match s7Q10)
Fact Sheet
Permit Renewal 2024 -- NPDES NCO089451
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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.
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)]
25
Average Upstream Hardness (mg/L)
Total as, CaCO3 or Ca+M
25
7Q 10 summer cfs
0.0
1 10 cfs
0.0
Permitted Flow GD
0.025
Fact Sheet
Permit Renewal 2024 -- NPDES NC0089451
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