NC0004308_Correspondence_20221010

Badin Business Park LLC
201 Isabella Street
Suite 500
Pittsburgh, PA 15212-5858 USA
Tel: [phone]
October 10, 2022
Douglas Dowden
Environmental Program Supervisor II
Industrial NPDES Permitting Unit
Full Address
Re: Badin Business Park (BBP) — Response to NCDEQ Correspondence Dated 8/26/22
Permit NC0004308
Badin Facility, Stanly County
Dear Mr. Dowden,
Badin Business Park, LLC (BBP) appreciates the responses provided by the North Carolina
Department of Environmental Quality (NCDEQ) in the letter dated August 26, 2022, regarding
BBP's letters of May 27, 2022 and June 6, 2022.
Environmental compliance remains a high priority for BBP. As such, BBP has continued to
identify, evaluate, and take action to achieve compliance at Outfall 005. While the actions to date
have resulted in a significant reduction in fluoride in recent years, they have not achieved
consistent compliance with the fluoride limit at Outfall 005.
Throughout this effort, BBP has reviewed many practical and creative alternatives. And many of
these have been discussed with NCDEQ through meetings or proposed via more formal
mechanisms such as permit modification requests or a drafted Order of Consent. Like all
investigation and assessment activities, a systematic and iterative process has been employed to
evaluate both the causes for the fluoride in Outfall 005 as well as solutions to address it. As a
result, BBP's understanding has significantly evolved and water quality improvements have been
achieved; however, we recognize that we have only discussed this work with NCDEQ at a fairly
high level. We acknowledge that this approach unfortunately has not afforded some within
NCDEQ or certainly external stakeholders clarity on the complexity of the issue, the actions taken
to date, and practical measures that might be considered as additional actions. Therefore, BBP
agrees that the development of a formal alternatives analysis is prudent to assist stakeholders in
identifying sustainable solutions to manage the permitted stormwater discharges from the site.
BBP is taking immediate action to develop a Work Plan to support an alternatives analysis that
will assess options to reduce fluoride concentrations in the Outfall 005 discharge. The Work Plan
will include the options being considered including groundwater diversion, storm sewer
modifications, focused groundwater remediation and stormwater capture with blending, and

Douglas Dowden, Industrial NPDES Permitting Unit
BBP — Response to NCDEQ Correspondence Dated 8/26/22 — Permit NC0004308
Page 2
treatment for fluoride. In the assessment of groundwater and stormwater treatment alternatives
both in situ and ex situ approaches are being considered. The Work Plan will incorporate BBP's
extensive understanding of site conditions, including data from the recently completed
investigations, to identify and address informational gaps. The forthcoming study will involve a
detailed assessment of options including technology vendor evaluation, supplemental field
investigations, and carefully designed bench -scale feasibility testing. BBP proposes to submit a
detailed Work Plan to NCDEQ by November 30, 2022.
In conjunction with the Work Plan development, BBP wishes to meet with NCDEQ as soon as
possible to explore the viability of implementing one or more interim measures. These interim
measures will support activities being proposed in the Work Plan and may be part of the permanent
solution for management of fluoride concentration at Outfall 005. Proposal of these interim
measures stem from recent enhancements to the comprehensive Hydrogeologic Conceptual Site
Model (HCSM), introduced in the March 9 meeting with NCDEQ. It is proposed that this HCSM
will be submitted with the Work Plan, as concurrence on the HCSM (in particular sources and
transport pathways) is a critical component to the design, implementation of interim measures, and
the development of a permanent remedy. BBP is prepared to immediately implement any interim
measures agreed to in the requested meeting.
The remainder of this letter provides additional information to address specific requests made in
your August 26, 2022 letter. Items raised by NCDEQ are presented in italic text with detailed BBP
responses provided thereafter in regular text.
RESPONSE TO BBP's MAY 27, 2022 CORRESPONDENCE
1. Very Old Storm Sewer System: We appreciate the formal update referenced in line item 1 of the
May 27th correspondence. NCDWQ requests a summary with attachments of all studies performed
by BBP that "demonstrate the majority of the fluoride entering the system is a result of
groundwater infiltrating the very old storm sewer systems. " ...
BBP has conducted significant work to understand the contributions of fluoride and cyanide in the
site's storm sewer system. Much of the investigation tools and results reside outside of a formalized
report existing in independent laboratory analytical reports, video surveillance, infrastructure
drawings, monitoring well boring logs, etc. However as forementioned, in the last few months
much effort has been put forth to update the hydrogeologic model, which reviews and accounts for
much of the previous assessments. The advancements in the HCSM will be summarized and
submitted along with the Work Plan.
Critically this HCSM will document our understanding of the interactions between groundwater
and the stormwater drainage systems at the site and has narrowed the focus to key areas of the site
and sources that are potentially contributing fluoride to waters entering the NPDES Outfall 005

Douglas Dowden, Industrial NPDES Permitting Unit
BBP — Response to NCDEQ Correspondence Dated 8/26/22 — Permit NC0004308
Page 3
stormwater drainage system. BBP considers it critical that we reach consensus with NCDEQ on
this HCSM to ensure that our activities are focused on specific sources and migration pathways
and allow the identification of data gaps and uncertainties (if any are present) so that a final remedy
can be designed and effectively implemented.
2.... To date data submitted by BBP in eDMR routinely reflects exceedances for the pollutants
identified. Thus, under 15A NCAC 02B .0404 reasonable potential still exist for water quality
violations. Regardless of identifying the source(s) of fluoride and total cyanide within Outfall 005
the contaminated storm water can and should be treated using treatment technologies, thus
reducing, if not eliminating the potential of water quality violations from Outfall 005 in the future.
As discussed above, BBP will develop and submit a Work Plan to NCDEQ by November 30, 2022,
which will include bench -scale studies of the efficacy of fluoride treatment technologies.
3. Water Quality Standards and Table 1: NCDWR appreciates the formal update referenced in
line item 2 of the May 27th correspondence. Data provided does not demonstrate that fluoride
and total cyanide concentrations in Little Mountain Creek downstream of BBP consistently meet
water quality standards. Data provided by BBP via eDMR routinely reflects exceedances for the
pollutants identified.
No data to this subject were presented in the May 27th correspondence. The letter simply states
that during the March 9th meeting, BBP spoke to the water quality information collected by BBP
between 2019 and 2021. In summation, the available surface water monitoring data for Little
Mountain Creek does not show elevated concentrations (above NCDEQ criteria) and supports
the absence of unacceptable risk in the receiving environment. However, BBP recognizes that
this assessment was limited to Little Mountain Creek and consisted of a small dataset intended to
be representative of seasonal variation. The surface water sampling in Little Mountain Creek was
not conducted as part of the NPDES program and therefore not reported in the eDMR. However,
the Division of Water Resources was copied on each report submitted to the Hazardous Waste
Section.
...Under 15A NCAC 02B .0404 reasonable potential still exist for water quality violations of
acute and chronic criteria. The data in Table 1 provides flowrate in USG/min not based upon a
sanctioned / calibrated USGS data station for Little Mountain Creek. The data in Table 1 is not
reflective of the data provided by BBP in eDMR. Historical data from eDMR reflects a monthly
average flow —0.14 mgd with a maximum reported of 0.26 mgd. The data provided in Table 1
reflects significant variability which indicates the need for thorough data collection from USGS
(e.g. 5-10 years). The data is not comparable to low flow values as it could have high
inaccuracy, especially for a stream with high probability of zero -low flow. Thus, the facility must
meet end of pipe limits. Also, the data provided does not include any correlation to fluoride, total

Douglas Dowden, Industrial NPDES Permitting Unit
BBP — Response to NCDEQ Correspondence Dated 8/26/22 — Permit NC0004308
Page 4
cyanide concentrations, nor chronic criteria, nor include rainfall totals by month. Thus, the
value of the data is of limited use and is unsubstantiated.
Table 1 was provided in response to conversations and a request made by NCDEQ at the March
9th meeting. In this meeting BBP indicated it had been collecting flow data on LMC for several
years in accordance with a Work Plan requested and reviewed by the Hazardous Waste Section
and Division of Water Resources. No request was made to use such data in the permitting
process only as basis for comparing to past and recent USGS determinations of low -flow
characteristics.
Further, as discussed during the March meeting, the United States Geological Survey (USGS) has
been engaged to install a gauging station on Little Mountain Creek, with BBP acting as the sponsor
for this work. The sponsorship of this gauge was the basis of our June 6, 2022, letter. The content
of this letter was directly from an example provided to BBP from USGS for similar installations.
Since BBP will issue annual purchase orders to fund this effort, we were instructed by USGS to
cover only a one-year period in the letter and reissue notices annually.
3. Site Remediation Activities: We appreciate the summary of recent activities at the site
provided and agree that these actions "have been unsuccessful at bringing Outfall 005 into
consistent compliance with the fluoride limit" as expressed in line item 3 of the May 27th
correspondence. Based upon the information provided BBP has been unable to identify the
source(s) of fluoride in Outfall 005 on site.
Based on the extensive field programs recently completed at the site, BBP has made considerable
progress in developing an understanding of sources and transport pathways that are leading to
detections of fluoride in Outfall 005. As noted above, BBP proposes to submit an HCSM with
the proposed work plan which will document the findings of these assessments and critically
integrate historical investigations and assessments into a comprehensive discussion of sources
and groundwater/surface water interactions that are contributing to fluoride detections in NPDES
Outfall 005.
...NCDEQ does appreciate the technical discussion of various fluoride wastewater treatment
studies "all with mixed success, specifically with sustainable treatment of fluoride in
wastewaters to low ppm levels on a continuous or interim basis" in the "White Paper" entitled
"Re: Fluoride Removal from Industrial Wastewaters — A Technology Review ". The treatment
studies investigated had very high concentrations of Fluoride in an industrial effluent or
stormwater. BBP has a diluted mix of Groundwater and stormwater with a mean value of 2.1
mg/L for Fluoride (monthly average). BBP should perform pilot studies and literature reviews
relevant to Badin Business Park's situation where there are low concentrations (2-5 mg/L) of
Fluoride in stormwater/effluent.....

Douglas Dowden, Industrial NPDES Permitting Unit
BBP — Response to NCDEQ Correspondence Dated 8/26/22 — Permit NC0004308
Page 5
As discussed above, BBP will develop and submit a Work Plan to NCDEQ by November 30, 2022,
to study bench -scale and field scale efficacy of fluoride treatment technologies. The proposed
program of works will evaluate a broad suite of management and treatment methods including
both in -situ and ex -situ treatment alternatives.
4. Mixing Zones: NCDEQ appreciates the "considerable time and effort that BBP has taken to
investigate the potential for a direct discharge to Little Mountain Creek"; however, numerous
factors play into mixing zones. Most importantly, current USGS data is required to provide a 7Q10
determination. A single data point from a potentially abandoned USGS or WWTP station from 20
plus years ago cannot be used for a 7Q10 determination especially when USGS has made a more
recent determination. The effort to pursue this option was solely at the discretion of BBP
personnel. Further, under 15A NCAC 02B .0204 mixing zones will not:
i. result in acute toxicity to aquatic life or prevent free passage of aquatic organisms;
ii. result in offensive conditions;
iii. produce undesirable aquatic life or result in a dominance of nuisance species;
iv. endanger the public health or welfare.
Mixing zones can only be established on a case by case basis at the discretion of the NCDEQ per
15A NCAC 2B. 0204.
BBP may evaluate the option of a direct discharge to alternate water bodies in the Work Plan or
the alternatives analysis, as appropriate. It is understood that developing low -flow statistics for
riverine systems, such as Little Mountain Creek, can be a time intensive process; however, USGS
has been engaged to begin the data collection process to develop a substantiated data set.
Also, an ecological risk assessment, which includes Little Mountain Creek, is in progress and will
be addressing whether fluoride is causing unacceptable risk to aquatic receptors. This work is being
conducted under the Corrective Action Program under the supervision of the Hazardous Waste
Section with consult for United States Environmental Protection Agency (EPA), Region 4.
5. In response to specific assertions and/or proposals made in the May 27th, 2022 correspondence
the following responses are provided.
a. USGS Data Points: It is solely at the discretion of BBP to pursue, develop, propose and
possibly conduct a study to determine if a non -documented previous assessment of USGS data
can be validated.
Noted, see previous responses regarding working with USGS.
b. Unsubstantiated Flow Data Points: NCDWR is not able to permit a discharge to Little
Mountain Creek utilizing unsubstantiated `previously determined 7Q10" data that is now
outdated.
Noted.

Douglas Dowden, Industrial NPDES Permitting Unit
BBP — Response to NCDEQ Correspondence Dated 8/26/22 — Permit NC0004308
Page 6
c. Hydrograph-Controlled Release: The data provided in Attachment 1 of the May 27th
correspondence is irrelevant to this discussion. Each state and each waterbody within each state
has its own applicable rules, regulations, and requirements and thus data regarding what has
transpired in Florida, Georgia, Kentucky, Alabama, and South Carolina is not applicable.
NCDWR must adhere to the rules and regulations as established by the North Carolina
Environmental Management Commission and the EPA. Specifically, in regards to the proposed
Hydrograph-Controlled Release (HCR) by fin Associates Ltd; this approach is not an acceptable
method within NC under 2B water quality regulations to address the discharge volume of
fluoride to Little Mountain Creek...
The memorandum written by FTN Associates LTD, was provided in response to a comment
during the March 9th meeting summarized as, "EPA will not authorize the use of HCR or flow -
based discharge limitations". The memorandum was written to provide a summary of the
technical approach and provide examples of where Region 4 has previously allowed such
discharges to be permitted.
...Additionally, evaluation of the data submitted raised the following concerns:
i. Based upon the HCR proposal (Attachment 1 of the 5/27/22 BBP correspondence)
developed by fin Associates Ltd it appears that BBP may have data that reveals
pollutant sources upstream of the site were caused by past site activities. NCDWR
request copies of all data that indicate existence of pollutants and/or pollutant sources
upstream of the site.
This statement is unclear. It is assumed that NCDEQ is referring to the upstream background
surface water concentration of fluoride in Little Mountain Creek (0.09 mg/L). No
upgradient/upstream pollutants are linked to this concentration. Fluoride is a naturally present
element that is ubiquitous in freshwater. A concentration of 0.09 mg/L is within the range of
naturally occurring background fluoride concentrations in the state of North Carolina. As
mentioned above, information regarding these previous investigations has been provided to the
Division of Water Resources.
ii. The information supplied is not adequate; including, but not limited to the lack of
adequate USGS approved flow data. USGS flow stream data is typically based upon
an extended data set and thus the proposal "to establish a flow monitoring station in
Little Mountain Creek in order to update the historic 7Q10 determination" will not
timely address current discharge exceedances.
Noted, see previous responses regarding working with USGS but the benefit of an HCR
approach is that long term flow data is not needed because allowable discharges are based on
real-time assimilative capacity rather than historical flow statistics.

Douglas Dowden, Industrial NPDES Permitting Unit
BBP — Response to NCDEQ Correspondence Dated 8/26/22 — Permit NC0004308
Page 7
iii. Based upon the limited information supplied the facilities that operate under a HCR
scenario are the exception rather than the rule. They are generally used for DO
concerns and most states do not allow HCR's to address exceedances for toxicants. In
addition, the scenarios provided are not similar to the conditions at BBP and Little
Mountain Creek.
Noted; however, HCR discharges are being used in a wide range of situations across the country,
including discharges that contain toxicants and have small receiving streams (specific examples
will be provided upon request if deemed viable).
iv. The proposal indicates "the daily maximum concentration limits would be equal to the
criteria to protect from acute toxicity (24 mg/L fluoride and 46.6 ,ug/L cyanide) ". Any
proposal should address all chronic and acute water quality standards.
Noted.
6. Treatment Options: We understand that BBP has evaluated various treatment options to address
pollutant discharges off site involving fluoride at their sites worldwide. NCDEQ appreciates the
detailed technical information provided in Attachment 2, specifically within the "White Paper"
entitled "Re: Fluoride Removal from Industrial Wastewaters — A Technology Review ".
a. As stated previously BBP should fully evaluate all options to address water quality violations,
including options to treat storm water prior to discharge and continue efforts to find and eliminate
all pollutant sources (e.g. some form of site remediation activities). As discussed with NCDEQ
Assistant Secretary for the Environment, Sushma Masemore, at the meeting in March 2022, BBP
should explore and present to DWR available technologies relevant to the BBP situation to address
water quality exceedances. This office believes that all available technologies have not been
explored and BBP shall assess, through literature reviews and facility funded pilot studies,
treatment technologies for low concentrations of Fluoride (2-5 mg/L) in stormwater/effluent. The
results from such efforts should be translated to construction and installation of a satisfactory
treatment system. Again, we appreciate the time and effort put into developing this white paper;
however, recurring water quality violations must be addressed.
BBP has conceptually evaluated treatment technologies in relation to the discharge at Outfall 005.
However, due to the variable nature of the Outfall flow volumes, traditional treatment has not been
considered a practical option for the site; therefore, the bulk of the effort to date has revolved
around source identification and removal. However, as discussed above, BBP will include
treatment technologies (both ex -situ and in -situ) in the Work Plan to be submitted to NCDEQ.
This study will look to perform bench -scale testing of fluoride treatment technologies, where
warranted. The bench scale testing will be combined with focused field investigations which will
include assessment of groundwater/surface water geochemistry, stormwater system hydraulics,

Douglas Dowden, Industrial NPDES Permitting Unit
BBP — Response to NCDEQ Correspondence Dated 8/26/22 — Permit NC0004308
Page 8
validation of our understanding of groundwater\surface water interactions and supplemental soil
and groundwater assessments to further delineate potential sources. Some of this work will be
conducted in an iterative manner but it is considered that a number of the work scopes to be
documented in the Work Plan can be conducted in parallel.
SUMMARY
We trust the responses and enclosed documentation address NCDEQ's request for additional
information. BBP will submit to NCDEQ by November 30, a detailed Work Plan (and supporting
HCSM) which will document the proposed program of works. We also request a meeting at your
earliest convenience to explore concurrent interim measures as discussed above.
Again, thank you for providing the information to BBP. We look forward to working
collaboratively to clearly define the best path forward with the preparation and review of the Work
Plan. If you have any questions or wish to discuss our comments, please feel free to contact me at
412.389.1768 or [e-mail].
Thank you,
Robyn L. Gross
Director, Asset Management Americas
Badin Business Park LLC
cc via email:
Amir Adaryani, NCDEQ
Corey Basinger, NCDEQ
Julie Grzyb, NCDEQ
Cameron Henley, Moore & VanAllen
Joy Hicks, NCDEQ
Sushma Masemore, NCDEQ
Jason Mibroda, Alcoa Corp.
Michael Montebello, NCDEQ
Richard Rogers, NCDEQ
Michael Scott, NCDEQ
Cameron Henley, Moore & VanAllen