NC0089109_Fact Sheet_20190417

NCDEQ/DWR
FACT SHEET FOR NPDES PERMIT DEVELOPMENT
MAJOR MODIFICATION/RENEWAL
American Zinc Products, LLC
NCO089109
Facility Information
(1.) Facility Name:
........................................................................................................................................................:..............................................................................................................................................................................................................................................................................................................................................
American Zinc Products, LLC
(2.) Permitted Flow (MGD):
0.98
(6.) County:
Rutherford
:..................................................................................
............. ................................................................ ...........................................................................:.......................
(3.) Facility Class:
.............................................................................................
II
.......................................................................................................................................
(7.) Regional Office:
Asheville
........................................................................................................................................................:
(4.) Pretreatment Program:
..................................................:.....................................................................
...................................................................................................................
N/A
....................................ov...................................................................................................................................................................................
(8.) USGS To o Quad:
F11SW
........ ......................................... ................................................
(5.) Permit Status:
.........................................................................P.................................................................:..................................................................................
Major Modification and
(9.) USGS Quad Name:
Renewal
Stream Characteristics
(1.) Receiving Stream:
Broad River
(7.) Drainage Area (mi2):
575
... .......... .....................................................................................
(2.) Sub -basin:
..:...................................................................................................................
03-08-02
......................................................�............................................................................:..................................................................................
(8.) Summer 7Q10 (cfs):
167
........................................................................................................................................................:..........................................................................................................................................................................................................................................................:..................................................................................
(3.) Stream Index Number:
9-(36.5)
(9.) Winter 7Q10 (cfs):
334
..........................................................................................;....................................................................................................................,......................................................................................................................................
(4.) Stream Classification:
WS-IV
(10.) 30Q2 (cfs):
...................................................
403
........................................................................................................................;....................................................................................................................,......................................................................................................................................
(5.) 303(d) Status:
Not listed
(11.) Average Flow (cfs):
...................................................
914
......................................................................................................................;....................................................................................................................,......................................................................................................................................
(6.) 305(b) Status:
(12.) IWC %:
........................................................
0.9
Sum
This is a Major Modification and a Renewal for the permit for American Zinc Products,
LLC. The Major Modification and Renewal is conducted to accommodate the flow increase
in the permit. The facility is located in the southern portion of the Rutherford County. The
facility uses the impure zinc oxide that is generated from the parent company's (AZR)
recycle plants, which recycle Electric Arc Furnace (EAF) dust. The EAF dust is a zinc
containing waste generated by the North American steel mini mills. The facility will produce
approximately 55,000 tons of Special High grade Zinc metal. The process will include zinc
oxide leaching, extraction of zinc with an organic ligand electrowinning, and casting. The
facility will achieve significant degree of recycling of the reagents that are used in the
process. This will be a first facility of this type in the USA, and there are no effluent
guidelines for Zinc recycling facilities.
The facility went through a bankruptcy in 2016 and has not produced any zinc since that
time. It is currently undergoing substantial changes and improvements to the production and
wastewater facilities. It is scheduled to re -open in the Spring of 2019.
Potable water and sanitary sewer service for the facility is provided by the Forrest City.
Antideaadation review
Per NC antidegradation policy (15A NCAC 213.0201, each applicant for an NPDES permit
expansion must document an effort to consider non -discharge alternatives pursuant to 15A
NCAC 2H.0105(c)(2). The original estimates for the wastewater flow submitted by the
Page 1 of 9

NPDES Permit Fact Sheet — 04/ 16/ 19
Page 2
American Zinc Products, LLC
NCO089109
facility prior to the beginning of the production were incorrect. The facility employs a new
technology that has not been used for Zinc production in this country. Therefore, it was
difficult to correctly calculate a flow limit for the new facility, the re -calculated flow estimate
is 0.98 MGD. The updated EAA was submitted by the facility on September 6, 2017. The
EAA was approved on September 29, 2017, it allows discharge of 0.98 MGD treated
industrial wastewater. The wastewater generated by the facility is essentially a clean brine
solution that has a very high concentration of chlorides (17,000 mg/L). Hence, the non -
discharge options are not viable. If this wastewater is discharged to the soil surface or into
the infiltration galleries, it will contaminate the soil and the aquafer. The Forrest City POTW
is also unable to treat this discharge since it will cause a major toxicity problem and likely
destroy the microbial biomass in the treatment system, which will result in a complete failure
of the POTW.
Therefore, DWR staff concurred with the EAA conclusion that expansion at the current
location was the most environmentally sound alternative from the reasonably cost-effective
options (per 15A NCAC 214.0105).
Compliance Schedule
Due to the recent changes in the state water quality standards, the new dissolved state
standard for Cadmium has become more stringent. Review of the effluent data indicated that
the facility will not be able to comply with the new permit limit for Cadmium. The facility
conducted a bench -scale testing with the effluent to evaluate various treatment options.
Based on the results of the test the facility proposed a 10-year compliance schedule. The
Division discussed the schedule with the applicant and negotiated a reduced compliance
schedule of 7.5 years, it will be added to the permit.
Compliance History
The facility has experienced numerous production and compliance issues since the start-up,
which led to the bankruptcy in February of 2016. The facility has been purchased by a new
owner and completed several improvement projects.
RPA
The RPA (reasonable potential analysis) was updated to incorporate a new flow limit of 0.98
MGD. The modification application identified the number of pollutants that might be
present in the discharge. The RPA was conducted for these pollutants: arsenic, cadmium,
chlorides, chromium, copper, fluoride, lead, nickel, zinc, tin, and antimony.
The RPA indicated that the limits are necessary for total cadmium. Due to the recent
updates to the state standard, the cadmium standard has been significantly reduced. The
facility requested a compliance schedule to design a treatment system for cadmium removal.
The compliance schedule was added to the permit.
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NPDES Permit Fact Sheet - 04/ 16/ 19
Page 3
Summary of Permitting Actions
American Zinc Products, LLC
NCO089109
Parameter
Current Permit
Proposed
Change
Basis for Condition/Change
Flow
0.8 MGD
0.98 MGD
15A NCAC 2H.0105
NH3-N
Quarterly monitorin
No change
Parameter of concern
TSS
Monitoring - 2/Month
No change
Parameter of concern
Total Aluminum
Quarterly monitoring
No change
Parameter of concern
Total Antimony
Quarterly monitoring
No change
Parameter of concern
Total Arsenic
Quarterly monitoring
No change
Parameter of concern
Total Cadmium
MA 0.27 mg/L
MA 90.4 µg/L
WQBEL. State WQ standard, 15A
DM 1.66 mg/L
DM 454.4 µg
NCAC 2B .0200. New limits are based
on the new dissolved standard
Chlorides
Quarterly monitoring
No change
Parameter of concern
Total Chromium
MA 6.75 mg/L
Limit and
Based on the results of the Reasonable
DM 113.6 mg/L
monitoring
Potential Analysis. Total Chromium is
removed
no longer has a state standards.
Chromium (VI)
No requirement
Quarterly
Parameter of concern, monitoring
monitoring
added because the valence of the
chromium present in the discharge is
unknown
Total Cobalt
Quarterly monitoring
No change
Parameter of concern
Total Copper
Quarterly monitoring
No change
Parameter of concern
Total Fluoride
MA 243.2 mg/L
Limit removed,
Based on the results of the Reasonable
DM 243.2 mg/L
Quarterly
Potential Analysis.
monitoring
Total Iron
Quarterly monitoring
No change
Parameter of concern
Total Lead
MA 3.37 mg/L
Limit removed,
Based on the results of the Reasonable
DM 3.75 mg/L
Monitoring -
Potential Analysis.
2/Month
Total Nickel
Monthly monitoring
No change
Parameter of concern
Total Tin
Quarterly monitoring
No change
Parameter of concern
Total Zinc
Monitoring - 2/Month
No change
Parameter of concern
PH
6.0 - 9.0 SU
No change
WQBEL. State WQ standard, 15A
NCAC 2B .0200
Toxicity Test
Chronic limit, 0.74%
Chronic limit,
WQBEL. No toxics in toxic amounts.
effluent.
0.9% effluent.
15A NCAC 2B.0200 and 15A NCAC
213.0500
Turbidity
Monitoring in the
No change
Parameter of concern
effluent, upstream and
downstream
Fish tissue
No requirement
Sampling one
Added to address a comment from the
monitoring
time during the
regional office
permit cycle
Priority Pollutant
No requirement
Sampling one
Added to address a comment from the
Scan
time during the
regional office
permit cycle
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NPDES Permit Fact Sheet — 04/ 16/ 19
Page 4
MA- monthly average
DM -Daily Maximum
Antibacksliding Review
American Zinc Products, LLC
NCO089109
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: N/A
Proposed Schedule for Permit Issuance
Per 15A NCAC 214.0109 & .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-day comment period indicating the interest
of the party filing such request and the reasons why a hearing is warranted.
Draft Permit to Public Notice: January 29, 2019 (est.)
Permit Scheduled to Issue: March 20, 2019 (est.)
State Contact Information
If you have any questions on any of the above information or on the attached permit, please
contact Sergei Chernikov at [phone], or sergei.chernikovgncdenr.gov.
Changes in the Final Permit
The Final Permit contains no significant changes from the Draft Permit.
Fact Sheet Attachments
• RPA Spreadsheet Summary
• Dissolved Metals Implementation/Freshwater or Saltwater
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NPDES Permit Fact Sheet - 04/ 16/ 19
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American Zinc Products, LLC
NCO089109
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/l
(Dissolved)
Chronic FW, µg/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 I11
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 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, µ /l
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] -
3.62361
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}
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NPDES Permit Fact Sheet — 04/ 16/ 19
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American Zinc Products, LLC
NCO089109
Copper, Acute
WER*0.960 e"{0.9422[ln hardness]-1.7001
Copper, Chronic
WER*0.960 e^10.8545[ln hardness]-1.7021
Lead, Acute
WER* { 1.46203- [ln hardness] (0.145712)) e^ 11.273 [ln hardness] -
1.4601
Lead, Chronic
WER* { 1.46203- [ln hardness] (0.145712)) e^ 11.273 [ln hardness] -
4.7051
Nickel, Acute
WER*0.998 e^{0.8460[ln hardness]+2.2551
Nickel, Chronic
WER*0.997 e^10.8460[ln hardness]+0.05841
Silver, Acute
WER*0.85 • e^11.72[ln hardness]-6.591
Silver, Chronic
Not applicable
Zinc, Acute
WER*0.978 e^{0.8473[In hardness]+0.8841
Zinc, Chronic
WER*0.986 e^10.8473[ln hardness]+0.8841
General Information on the Reasonable Potential Anal, sis (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.
To perform a RPA on the Freshwater hardness -dependent metals the Permit Writer
compiles the following information:
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NPDES Permit Fact Sheet — 04/ 16/ 19
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American Zinc Products, LLC
NC0089109
• 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/4 + (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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NPDES Permit Fact Sheet — 04/ 16/ 19
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4. The
American Zinc Products, LLC
NCO089109
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:
Cdis --I
Ctotal 1 + { [Kpo] [sslt+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.
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 = (s7010 + Ow) (Cy cgs)-(s7010)(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* (tg/L or mg/L)
Qw = permitted effluent flow (cfs, match s7Q10)
s7Q10 = summer low flow used to protect aquatic He 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
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NPDES Permit Fact Sheet — 04/ 16/ 19
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American Zinc Products, LLC
NC0089109
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)
25.0
Default value
[Total as, CaCO3 or (Ca+M )]
Average Upstream Hardness
(mg/L)
25.0
Default value
[Total as, CaCO3 or (Ca+M )]
7Q10 summer cfs
0
Lake or Tidal
1Q10 (cfs)
0
Lake or Tidal
Permitted Flow (MGD)
2.1
For dewaterin
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