2022.06.20_Response_Cover

PIEDtAONT
LITHIUM
Responseto
Additional
Information
Request
(dated January 14, 2022)
Carolina Lithium Project
Piedmont Lithium Carolinas, Inc.
Gaston County, North Carolina
June 20, 2022

P I E DMO N T
LITHIUM
June 20, 2022
Mr. David Miller, PE
NC Department of Environmental Quality
Division of Energy, Mineral, and Land Resources
1612 Mail Service Center
Raleigh, NC 27699-1612
SUBJECT: Piedmont Lithium Carolinas, Inc.
Piedmont Lithium Carolinas, Inc.
42 Catawba St.
Belmont, NC 28012
Carolina Lithium Project
Response to Additional Information Request, dated January 14, 2022
Dear Mr. Miller:
Piedmont Lithium Carolinas, Inc. (PLCI) would like to thank you for your January 14, 2022
comments in response to our December 15, 2021 Response to Additional Information Request for
the proposed Carolina Lithium Project (Project). The proposed Project consists of the mine
excavation and corresponding infrastructure, Concentrate Operations, and a Lithium Hydroxide
Conversion Plant.
Please see the following responses to your Additional Information Request. Comments. The
agency comments are in bold text and responses are provided in regular text. Two copies of this
response are provided, including an electronic version.
Should you have any questions or require additional information following your review of the
enclosed materials, please contact either Patrick Brindle at [phone] or
pbrindle piedmontlithium.com or Monique Parker at [phone] or
mparker(a-)piedmontlithium.com.
Yours truly,
Awl
Patrick H. Brindle
Executive Vice President and Chief Operating Officer
Piedmont Lithium Carolinas, Inc.
Monique Parker, CSP
Vice President — Safety, Environment and Health
Piedmont Lithium Carolinas, Inc.
Page 1 of 8

Attachments:
Piedmont Lithium Carolinas, Inc. I Carolina Lithium Project
Response to Mine Permit Additional Information Request
June 20, 2022
Appendix A: Water Supply Well Mitigation Plan
Appendix B: Response to DEMLR Mooresville Regional Office Comments
Appendix C: Response to DWR-WQPS Concerns
Appendix D: Updated Archaeological Survey of the Carolina Lithium Mine
Project Expansion, Gaston County, North Carolina
Appendix E: Waste Rock Pit Backfill Plan —Technical Specifications
Appendix F: Solid and Liquid Waste Flowsheets
Page 2 of 8

Piedmont Lithium Carolinas, Inc. I Carolina Lithium Project
Response to Mine Permit Additional Information Request
June 20, 2022
For the following items, the Division still has questions concerning the Company's
December 16, 2021, reply to the Division's October 29, 2021, Additional Information
Letter. All other items from the October 29, 2021 have been resolved.
Item 1(a): Requested MSD sheets for the chemicals being added to the Chemical and
Separation processes.
Piedmont Lithium Carolinas, Inc. (PLCI) Reply: Supplied MSD sheets for the
reagents being used.
Review: Division of Waste Management (DWM), still under review.
Division of Water Resources — Industrial Waste Program (DWR-IW), still
under review.
DWR-Aquatic Toxicology Branch (DWR-ATB), the flocculent listed is not
on the approved list.
Status: Please provide proof that the reagent list has been reviewed and found to
be acceptable to DWR-ATB. There could be additional requests
concerning this item.
After a conversation with DWR-Aquatic Toxicology Branch on February 9, 2022, we were able to
align on reagent use and the methods of use. It was determined there will be no reagents that will
be applied directly to the land or directly added to water that will flow directly into an aquatic body.
We agreed that waters that will be discharged into an aquatic body will be covered by a
Stormwater and/or Industrial Wastewater permit.
Item 2: Requested a copy of the Well Supply Mitigation Plan.
PLCI Reply: A response plan was provided.
Review: Based on initial review, the plan does not make it clear that the complainant
can go through either Division of Energy, Mineral, and Land Resources
(DEMLR) or Piedmont Lithium (PLCI). If the complainant contacts DEMLR,
then DEMLR can engage PLCI.
DEMLR would make an independent assessment using the resources of DEQ.
PLCI needs to notify DEMLR-Mining Program of all complaints in a timely manner
and when the matter is resolved.
PLCI must state what water needs it will be suppling if item 4 of their plan is
activated.
Status: The plan is still under review, will require further modifications.
See Appendix A for a revised Water Supply Well Mitigation Plan addressing comments.
Page 3 of 8

Piedmont Lithium Carolinas, Inc. I Carolina Lithium Project
Response to Mine Permit Additional Information Request
June 20, 2022
Item 3. Supply proof that the company has applied for NCG02 Stormwater permit.
PLCI Reply: A statement that they applied for the permit.
Review: DEMLR-Stormwater Program reviewed the application and found the site did
not qualify for the NCG002. The Stormwater Program did inform the
Company by letter that the Company needs to get an Individual NPDES
permit.
Status: The Company will need to supply proof that an Individual NPDES Permit has
been received for the mine site.
PLCI is currently awaiting results from Leaching Environmental Assessment Framework (LEAF)
testing so a determination can be made in collaboration with DEMLR-Stormwater Program and
DWR-WQPS as to the type of permit required.
Item 7: Explain any adjustments PLCI might make to the blasting program on a cloudy
day?
PLCI Reply: Will check with local airport to make sure there is no inversion.
Review: Reply does not state what PLCI will do if an inversion is present. Nor does
the Company define what constitutes a cloudy day.
Status: PLCI needs to supply further information on how they are going to handle
days when blasting conditions are less than ideal. The Company needs to
explain how they will document this.
Note: The Company might be advised to move away from what constitutes a
"cloudy day" and define what weather conditions will trigger a modified blasting
plan, then use the airport as a reference to determine if those condition are present.
PLCI's operations manual will be updated to include the following regarding its' blasting plan:
Before any loading begins, the blaster in charge will review the weather conditions with a visual
observation and confirm the temperature and wind conditions. The blaster will access the FAA
Meteorological Terminal Aviation Routine Weather Report (METAR) data from Charlotte
Douglas International Airport (CLT) for partly cloudy cover meaning 3/8ths to 4/8ths cloud cover,
or cloudy cover meaning 5/8ths or more cloud cover. The blaster in charge will communicate
with mine management to determine if modifications to the blasting plan will be required. Some
possible modifications may include one or a combination of the following measures:
1. Increasing the stemming heights or covering bore hole collars with sand or mats to
reduce pressure pulse into the atmosphere
2. Adjusting front row hole loads to minimize the chance of ejection pulse through the free
face
3. Adjusting the blast timing plan to compensate for adverse conditions
Page 4 of 8

Piedmont Lithium Carolinas, Inc. I Carolina Lithium Project
Response to Mine Permit Additional Information Request
June 20, 2022
The blaster in charge may identify and implement additional adjustments to the blast plan based
on the site conditions. Seismographs will be deployed for all blasting activities so that the
effectiveness of any blast plan modifications can be monitored in accordance with maintaining
overpressure values within state limits.
Any adjustments to the blasting plan, along with the weather conditions, will be documented in
the shot report; which will be maintained onsite, for each blast.
For the following items, the Division requires clarification on PLCI's December 16, 2021
response to information requested by agencies, Departments or Division:
Item 1:MRO comments concerning the submitted erosion and sedimentation control
plans.
PLCI Reply: PLCI submitted revised drawings.
Status: MRO still has concerns regarding the plans. PLCI need to contact Zahid
Khan, Mooresville Regional Engineer at 704-235-2145 to resolve their
concerns with the plan.
After consultation with the Mooresville Regional Office (MRO) team including Zahid Khan on
February 3, 2022, PLCI was able to gain a better understanding of their concerns with previously
provided information. The list included items such as connection between the drawings, the lack
of skimmers within the design and other administrative items. MRO feedback has been
addressed in the updated drawings.
Appendix B addresses each item and also includes updated drawings, detailed information, and
drainage calculations. This Appendix is provided in its own separate binder for ease of review
with the associated drawings.
Item 2(a & b): Submit copies of agreements between PLCI and publicly owned sewer
operations concerning the liquid waste being discharged into the sewer
system. Supply a chemical analysis of the waste.
PLCI Reply: PLCI submitted a letter and a Technical Memorandum between PLCI
and Two Rivers Utilities, concerning this matter.
PLCI has requested that the materials supplied be treated "as good faith evidence
that ongoing coordination with the local sewer provider is occurring to discharge
their processed wastewater effluent to a POTW with pretreatment." PLCI did not
supply chemical analysis of the waste.
Review: The Division of Water Resources -Water Quality Permitting Section-NPDES
Industrial Permitting Unit (DWR-WQPS) reviewed the documentation and
raise many concerns. Please see the attached document.
Page 5 of 8

Piedmont Lithium Carolinas, Inc. I Carolina Lithium Project
Response to Mine Permit Additional Information Request
June 20, 2022
Status: PLCI needs to address DWR-WQPS concerns as presented in the attached
document.
See Appendix C for response to DWR-WQPS concerns.
Item 4(a): Supply proof the site has received an Air Permit.
PLCI Reply: PLCI is still in the process of applying to Division of Air Quality for a
permit.
Status: PLCI needs to supply proof they have received an air quality permit for the
facility.
PLCI has not received and air permit for this site. A pre -application meeting was held with North
Carolina Division of Air Quality on June 13, 2022. Final preparations are being made to the air
permit application which will be submitted no later than early July 2022.
Item 6: Supply an archaeological study.
PLCI Reply: PLCI supplied a copy of the study.
Review: North Carolina Department of Natural and Cultural Resources -State
Historical Preservation Office reviewed the document. The Office supplied
a Memorandum listing their concerns, attached.
Status: PLCI needs to address the concerns raised in the Memorandum.
See Appendix D for the updated report based on all comments provided by the State Historical
Preservation Office.
After further discussion and review of your application, the following issues have been
identified and need to be addressed. It should be noted that the following represents new
requests, and for this reason the amount of time you have to address all of the issues
raised by this letter has been reset to 180-days.
Item 1: To ensure compliance with NCAC §74-53 (4), please provide the PLCI's plan on how
it is going to back fill the East Pit and the South Pit. This plan must contain as a
minimum:
a. Thickness of each lift.
b. The lift will have to be compacted.
1. What percent compaction will be achieved?
2. How will the compaction be measured (type of instrument or test to be
used)?
Page 6 of 8

Piedmont Lithium Carolinas, Inc. I Carolina Lithium Project
Response to Mine Permit Additional Information Request
June 20, 2022
3. Supply proof that the instrument or test will be adequate to measure the
thickness of the lift to ensure compaction levels have been achieved.
4. What will be the frequency of the test (amount of surface area per test)?
5. How will the measurements be recorded?
c. How long will it take the material to achieve 90% of its subsidence?
d. Certify that the plan will ensure that no pools of water on the finished grading will
develop due to subsidence.
e. How the company will address any pools that might develop after final grading?
See Appendix E for the Waste Rock Pit Backfill Plan — Technical Specifications.
Item 2: Please supply a comprehensive flowsheet showing both solid and liquid waste
discharges from the Separation Plant and the Chemical Plant. The flowsheet must
show at a minimum:
a. A description of the materials including:
I. Any reagents that might be present.
II. The concentration of the reagents.
III. Any product that will degrade and what are the by-products.
b. Worst case, how much of the material would be sent to the waste pile or the pit
hourly and annually?
c. How frequently will the material be sampled and for what parameters?
See Appendix F with the corresponding flowsheets for solid and liquid waste.
For solid and liquid waste, details responding to (a) and (b) above are included in their
representative flowsheets.
At this time, we are not able to provide a detailed answer as to what parameters will be evaluated
due to ongoing wastewater analysis work and LEAF testing. Upon receipt of this data, we will
work closely with the designated agency or department to algin on frequency of sampling (at least
quarterly) and parameters to be evaluated.
Item 3: Please supply proof that PLCI has received all necessary permits required by DWR-
WQPS, or documentation from DWR-WQPS stating that a given permit is not
required.
PLCI has not received all necessary permits required by DWR-WQPS. We are currently awaiting
results from Leaching Environmental Assessment Framework (LEAF) testing so a determination
can be made in collaboration with DEMLR-Stormwater Program and DWR-WQPS as to the type
of permit required.
Page 7 of 8

Piedmont Lithium Carolinas, Inc. I Carolina Lithium Project
Response to Mine Permit Additional Information Request
June 20, 2022
Item 4: Your application is inadequate to determine whether the reclamation plan will
prevent leaching of pollutants to groundwater. To avoid triggering NCAC§74-
51(3), Please provide:
a. A protocol for analyzing all waste products, including the pit waste, to
determine the pH range in which the material will not leach.
b. The number of samples that will be analyzed to achieve statistical confidence
that the pH range is appropriate to prevent leaching.
c. Explain how the waste disposal areas will be zoned/encapsulated to ensure that
if any leachate forms, it will not migrate?
d. How will the waste pile be treated to ensure proper pH control?
Please find below responses to above questions.
a. PLCI along with MMA and Energy and Environment Innovation joined together to develop
a detailed plan to conduct Leaching Environmental Assessment Framework (LEAF)
testing to analyze all waste products that would be collected either on the waste rock pile
or as backfill into the excavated mine pits. At this time, all data is not available. Once
complete, a technical memo will be provided highlighting the plan, its results, and
proposed management based on results.
b. The samples that were or are currently being analyzed include:
1. Potentially acid generating (PAG) waste rock
2. Non-PAG waste rock
3. Tailings
4. Various combinations of waste rock and tailings
In order to show statistical confidence, testing has included testing using natural and
Synthetic Precipitation Leaching Procedure (SPLP). Testing was also conducted using pH
ranges from 9 — 4 including duplicates.
c. Once results are received, we will be able to provide an answer to this question.
d. Once results are received, we will be able to provide an answer to this question.
Page 8 of 8

PIEDMONT
Appendices
Response to Additional
Information Request
(dated January 14, 2022)
Gaston County, North Carolina
June 20, 2022

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