Appendix E - Water Supply Well Mitigation Report

Technical Report
Water Supply Well Mitigation Plan
Kings Mountain Mining Project
Rev 03
Report Date: April 12, 2024
Report Prepared for
A ALBEMARLE"
Albemarle Corporation
4250 Congress Street
Charlotte, NC 28209
Report Prepared by
.11,k consulting
SRK Consulting (U.S.), Inc.
999 17t" Street, Suite 400
Denver, CO 80202
SRK Project Number: USPR000576
Albemarle Document Number: KM60-EN-PN-9241
Authored by:
Chad Bearor, BS Geology
Cansu Perdeli Demirkan, PhD
Carolyn D. Lambert, M.S., P.G.
Reviewed by:
Goktug Evin, BSc Eng, C.P.G., SME-RM

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Water Supply Well Mitigation Plan—Kings Mountain Page ii
Table of Contents
1 Introduction.................................................................................................................. 1
1.1 Background.........................................................................................................................................1
1.1.1 Kings Mountain........................................................................................................................1
1.1.2 Archdale ..................................................................................................................................2
1.2 Property Locations..............................................................................................................................2
1.3 Overview.............................................................................................................................................4
1.3.1 Kings Mountain........................................................................................................................4
1.3.2 Proposed Project Layout.........................................................................................................4
1.3.3 Archdale ..................................................................................................................................1
1.3.4 Proposed Archdale Layout......................................................................................................1
1.4 Summary of Proposed Mine Plan .......................................................................................................1
1.5 Objectives of the Study.......................................................................................................................1
1.6 Scope of Work.....................................................................................................................................1
2 Applicable Standards and Responsibilities............................................................... 2
2.1 National...............................................................................................................................................2
2.2 International ........................................................................................................................................2
2.3 Roles and Responsibilities..................................................................................................................2
3 Baseline Groundwater Conditions ............................................................................. 3
3.1 Groundwater Well Inventory ...............................................................................................................3
3.1.1 AECOM Groundwater Well Inventory .....................................................................................3
3.1.2 SRK Groundwater Well Inventory...........................................................................................5
3.2 Hydrogeologic Characterization Program...........................................................................................7
3.2.1 2018 to 2022 Field Characterization Program ........................................................................7
3.2.2 2023 Field Characterization Program .....................................................................................9
3.3 Conceptual Groundwater Model .......................................................................................................11
3.3.1 Kings Mountain......................................................................................................................11
3.3.2 Archdale ................................................................................................................................15
4 Impact Assessment ................................................................................................... 18
4.1 Numerical Groundwater Model .........................................................................................................18
4.1.1 Kings Mountain......................................................................................................................18
4.1.2 Archdale ................................................................................................................................18
4.2 Expected Groundwater Level Change..............................................................................................19
4.2.1 Kings Mountain......................................................................................................................19
4.2.2 Archdale ................................................................................................................................21
5 Baseline Data and Predictive Tools Improvement.................................................. 23
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5.1 Update of the Groundwater Well inventory.......................................................................................23
5.2 Monitoring Network...........................................................................................................................23
5.3 Predictive Tool Updates....................................................................................................................24
6 Trigger Action Response Plan (TARP) Development ............................................. 25
7 Stakeholder Engagement.......................................................................................... 27
7.1 Current Engagement Status .............................................................................................................27
7.2 Future Engagement Roadmap..........................................................................................................27
8 Well Mitigation Update Schedule.............................................................................. 29
9 References.................................................................................................................. 30
Disclaimer........................................................................................................................ 31
Copyright ......................................................................................................................... 31
List of Tables
Table 2.1: Roles and Responsibilities ................................................................................................................2
Table 3.1: Potential Wells within the Archdale 2-Mile Radius, Kings Mountain 4-Mile Radius, and 2023
Regional Groundwater Model Boundary ...............................................................................................5
Table6.1: TARP Example................................................................................................................................26
Table 7.1: Summary of SRK's Stakeholder Engagement Activities.................................................................27
List of Figures
Figure1.1: Location Map....................................................................................................................................3
Figure 1.2: Preliminary Kings Mountain Mining Project Site Map ......................................................................5
Figure 1.3: Proposed Archdale Tailings Facility Site Map..................................................................................1
Figure 3.1: Existing Well Location Map ..............................................................................................................4
Figure 3.2: Archdale/Kings Mountain Hydrocensus Overview...........................................................................6
Figure 3.3: Locations of Drilled Boreholes for Hydrogeological Study...............................................................8
Figure 3.4: 2023 Kings Mountain Borehole Locations......................................................................................10
Figure 3.5: Conceptual Hydrogeologic Model of Kings Mountain Pit Area ......................................................12
Figure 3.6: Kings Mountain Potentiometric Surface.........................................................................................14
Figure 3.7: Hydrogeological Assessment Study for Archdale Tailings Facility ................................................16
Figure 3.8: Archdale Potentiometric Surface....................................................................................................17
Figure 4.1: Extent of 5-Foot Drawdown Contour..............................................................................................20
Figure 4.2: Predicted Extent of 5-Foot Drawdown Contour Resulting from Pit Lake Dewatering....................22
Figure 5.1: Available Groundwater Monitoring Network Locations ..................................................................24
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Appendices
Appendix A: Predicted Water Level Changes at Monitoring Locations
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List of Abbreviations
The US System for weights and units has been used throughout this report. Tons are reported in short
tons of 2,000 lbs. All currency is in U.S. dollars (US$) unless otherwise stated.
Abbreviation Unit or Term
percent
Albemarle Albemarle Corporation
amsl above mean sea level
CEO chief executive officer
DEQ North Carolina Department of Environmental Quality
ERM ERM International Group Limited
ESI Environmental Simulations, Inc.
ft feet
ft b s feet below ground surface
GSV Goo le Streetview
NCDEQ North Carolina Department of Environmental Quality
NPI non-processing infrastructure
PAG otentiall acid generating
Project Kings Mountain Mining Project
SRK SRK Consulting (U.S.), Inc.
SWAP Source Water Assessment Program
TARP Trigger Action Response Plan
TDS total dissolved solids
TSF tailings storage facility
UN United Nations
UNGC United Nations Global Compact
VWP vibrating wire piezometer
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1 Introduction
The Kings Mountain Mining Project (the Project) is a previously developed open pit lithium mining
operation located in the city of Kings Mountain, North Carolina, in the southeastern United States. The
Project is a lithium pegmatite deposit that is currently being investigated for redevelopment by
Albemarle Corporation (Albemarle) as part of a prefeasibility-level analysis. Albemarle commissioned
SRK Consulting (U.S.), Inc. (SRK) to develop prefeasibility-level designs for an expansion of the
existing pit, rock storage facility (RSF) management, water management, and ancillary infrastructure
to aid Albemarle in making informed decisions regarding advancement of the Project. Tailings
generated from mining activities will be disposed of at the Archdale tailings storage facility (TSF)
(Archdale), a remote site approximately 3 miles south of the Project.
The detailed hydrogeological analysis for the Project and Archdale, incorporating field investigations
and regional groundwater modeling, has been extensively described in SRK(2023b and 2024).
1.1 Background
1.1.1 Kings Mountain
The following summary highlights the history of the site, compiled from records available to SRK:
• Mining started in 1883 with the discovery of cassiterite, a tin-bearing mineral, within the
outcropping pegmatites.
• Subsequently, open pit mining for tin occurred sporadically between 1903 and 1937 (Horton
and Butler, 1988).
• Between 1943 and 1945, under the sponsorship of the U.S. government, Solvay established
a processing plant and mined for spodumene from the outcropping pegmatites(Garrett,2004).
• In the early 1950s, Foote, a subsidiary of Newmont Mining Corporation, purchased the
property and began open pit mining (assumed at the beginning of 1955)and extracting lithium
from the spodumene.
• In 1993, exploration and mining operations ceased, when open pit bottom reached
approximately 660 feet(ft) above mean sea level (amsl).
• In early 1994, an open pit lake started to form due to groundwater and surface water ingress,
and the pit lake reached an elevation of 817 ft amsl (as of January 2023).
• During the pit lake recovery period (1994 to present), sporadic water pumping was recorded
from the Kings Mountain pit lake to a nearby quarry (Martin Marietta) to support quarry
operation.
• Albemarle acquired the site in 2015, resuming exploration and mine development activities.
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1.1.2 Archdale
The proposed TSF is located on a former mica mine. The following summary of the site is compiled
from records available to SRK:
• The site was formerly owned by the Kings Mountain Mica Company, which began operation
in 1949.
• The site was owned by several different companies, including Franklin Minerals, Oglebay
Norton, Zemex, General Chemical and Imerys, between 1994 and 2021.
• Imerys expanded mining to the nearby site in 2011.
The presence of pit lakes at Archdale since 2013 suggests that mining activities ceased around that
time. The current site layout encompasses several shallow pit lakes formed from the previous mica
mining operations.
1.2 Property Locations
Situated in Cleveland County, the facilities are approximately 35 miles west of Charlotte, North
Carolina. Located amidst rolling hills of the Piedmont Plateau, the Project and Archdale are in a
predominantly rural setting within the city of Kings Mountain. The Project covers approximately
1,075 acres, which include both the proposed extraction areas and associated processing
infrastructure. Archdale encompasses approximately 150 acres. Figure 1.1 shows the location and
extent of the Project and Archdale.
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1.3 Overview
1.3.1 Kings Mountain
The Project ore deposit is a Lithium-bearing rare-metal pegmatite intrusion that has penetrated along
the Kings Mountain shear zone, a regional structural feature known to host multiple lithium-bearing
pegmatites along its trend. The pegmatite field at Kings Mountain is approximately 1,500 ft wide at its
widest point in the legacy pit area and narrows to approximately 400 to 500 ft in width at its narrowest
point south of the legacy pit. The field has a lithium mineralization strike length of approximately
7,500 ft and is predominantly contained in the mineral spodumene. The spodumene pegmatite bodies
exhibit a texture-based variation in lithium grade, spodumene grain size, mineral alteration, and rock
hardness.
After dewatering the legacy pit, the lithium deposit is to be mined using conventional open pit mining
techniques. Blasting will fragment the ore and waste rock where it will be loaded and hauled to either
the processing facilities (ore) or the RSFs (overburden). The current plan includes mining in the
existing pit and expanding the pit to the southwest. Ore would be drilled, blasted, loaded, and
transported by haul truck to a new processing plant at a rate of—2.98 million tons per annum of ore
(-8,150 tons per day) and processed to produce 385 to 440 thousand tons per annum of spodumene
concentrate. The concentrate will be filtered to approximately 11 percent (%) moisture by weight and
transported off site for further refinement into lithium hydroxide monohydrate at a separate facility.
Tailings from the spodumene concentrate process will be filtered to approximately 10 to 15% moisture
content by weight and transported off-site to a nearby facility for disposal. A portion of the waste rock
with economic value as aggregate will also be transported off-site for sale.
1.3.2 Proposed Project Layout
The proposed layout is presented in Figure 1.2 showing the relative locations of the major components
of the Project. The Project is bisected northeast to southwest by Interstate 85. The headwaters of
Kings Creek are located immediately northeast of the site and the creek leaves the Project area at the
southern side of the Project area. The Phase 1 Open Pit outline is shown in the northeast area of the
Project, along with the ultimate (Phase 4) pit extents. Haul roads are shown connecting the Pit to the
RSFs; RSF-X located south centrally for Potentially Acid Generating (PAG)waste and RSF-A located
in the southwest for non-PAG (non-PAG) waste. The haul roads will also connect to the Non-
Processing Infrastructure (NPI) located in the northwest portion of the site and the ore sorting area
and the ore stockpiles, located on the east side of the project,just north of Interstate 85.A bridge over
Interstate 85 will connect the ore stockpile area to the processing area, located immediately south of
Interstate 85. South of the Processing Area,the Water Storage Basin 1 (WSB-1)will collect all contact
water produced within the Project area before being discharged from the site.
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AALBEMARL.B qti cMPyalu�' KINGS MOUNTAIN MINING PROJECT FIGURE C)�
Figure 1.2: Preliminary Kings Mountain Mining Project Site Map
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1.3.3 Archdale
Tailings from the spodumene concentrate process at Kings Mountain will be filtered to approximately
10%to 15% moisture content by weight and transported off-site to the Archdale facility for disposal. A
portion of the RSF may be transported to Archdale for construction of the TSF embankment.
An initial TSF embankment will be constructed on-site to hold approximately 1 year of filtered tailings.
The exact construction period is still being evaluated by the design team. The filtered tailings material
will be placed and compacted within a storage facility with mobile equipment. Over the life of the
Project, the TSF embankment will be raised, and the filtered tailings will continue to be placed until the
facility reaches its capacity. The facility will be closed once it reaches full capacity and reclaimed.
1.3.4 Proposed Archdale Layout
Figure 1.3 presents the proposed layout, showing the relative locations of the major components. The
Project is bounded by Interstate 85 on the southeast and Highway 24 on the northwest. Access to
Archdale will be off Highway 24 with a truck entrance and a light vehicle entrance. The site will include
minor office and maintenance facilities, parking, water storage facilities, and a TSF perimeter access
road. A small road base stockpile and growth media storage area are included in the site plan.
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1.4 Summary of Proposed Mine Plan
The main development elements will be widening and deepening of the existing open pit and Archdale
areas. Waste rock and mine tailings will be stored at Archdale. The active life of mine is expected to
be 11.5 years, including dewatering of the existing pit lake. Dewatering of the existing pit lake is
expected to last approximately 20 months, before mining operations can begin.
Albemarle has provided yearly pit development plans, which indicate that the open pit extension will
primarily be oriented towards the south (1,300 ft extension), with minimal expansions planned in the
east and west directions relative to the current pit. The northern wall of the existing open pit will not be
altered. The final pit bottom elevation is expected to reach 285 ft amsl by 2035.
1.5 Objectives of the Study
The key objectives of the Well Supply Mitigation Plan are to:
• Protect Water Supply: Ensure the preservation and protection of existing water supply wells
to sustain the availability of safe and reliable drinking and irrigation water.
• Monitor Drawdown Effects: Continuously monitor the impacts of drawdown on monitoring
wells and water supply wells to detect changes in water levels or quality promptly.
• Mitigate Drawdown Effects: Develop and implement strategies to mitigate adverse effects
on water supply wells caused by the Project's activities.
• Compliance with Regulations: Ensure that all mitigation actions comply with local, state,
and federal regulations governing water resource protection and well management.
• Community Engagement: Engage with affected communities,well owners, and stakeholders
to communicate mitigation efforts, gather feedback, and address concerns.
1.6 Scope of Work
The scope of the Well Supply Mitigation Plan encompasses ongoing monitoring throughout the
development and life of the mine and closure, as well as mitigation if adverse impacts are detected.
This Well Supply Mitigation Plan applies to impacts related to activities on the Project and Archdale
areas.
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2 Applicable Standards and Responsibilities
2.1 National
The Project must comply with various local, state, and federal regulations/standards that govern water
resource protection and safe well management. This ensures preservation/protection of existing water
supply wells and minimizes environmental/social impacts associated with dewatering of the existing
pit lake. Applicable standards/regulations that may apply include, but are not limited to, water quality
standards, well construction standards, and groundwater protection regulations established by North
Carolina Department of Environmental Quality (DEQ), North Carolina Mining Act, Clean Water Act,
the National Pollutant Discharge Elimination System program, Safe Drinking Water Act, and
Occupational Safety and Health Administration standards.
2.2 International
The Project must comply with applicable environmental, social, and governance standards and meet
sustainability targets developed by Albemarle at the site or corporate levels. Albemarle's 2022
sustainability report lists a portion of the committed global sustainability initiatives for the United
Nations (UN) Sustainable Development Goals, UN Global Compact (UNGC), and UNGC Chief
Executive Officer(CEO)Water Mandate (Albemarle, 2023).
2.3 Roles and Responsibilities
Albemarle commissioned SRK to conduct hydrogeological characterization studies, to develop the
Well Supply Mitigation Plan, and to develop conceptual and numerical models to support ongoing
engineering studies and permitting efforts to reactivate the project.
Table 2.1 provides an overview of the roles and responsibilities involved in implementing various
elements of the Plan. It is important to note that these roles and responsibilities may change during
the project development and implementation. As such, this section, like others in the Plan, needs to
be regularly reviewed and updated as needed. Further elaboration on the roles and responsibilities
will be provided once the relevant information becomes available.
Table 2.1: Roles and Responsibilities
Role Responsible
Management and mitigation planning SRK
Monitoring Albemarle
Data quality assurance Albemarle
Reporting Albemarle
Mitigation Albemarle
Community engagement Albemarle, ERM
Reviewing and updating the Plan To be determined
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3 Baseline Groundwater Conditions
3.1 Groundwater Well Inventory
3.1.1 AECOM Groundwater Well Inventory
A groundwater well survey was performed by AECOM (2022) within the vicinity of the project,
consistent with the extents of the groundwater impacts predicted by the numerical groundwater model,
as described in Section 3.3.2. The scope of the survey consisted of the following:
• Determine the source(s) of municipal water supply near the site. Municipalities included the
city of Kings Mountain, Cleveland County, and Gaston County.
• Review publicly-available information for public and private water supply wells within 4 miles
of the site. These included online databases (e.g., the Source Water Assessment Program
(SWAP) database and Cleveland County well construction and water sampling records) and
legacy reports that contained receptor surveys.
• Conduct a virtual drive-by inspection of properties within 2 miles of the site using Google
Streetview (GSV).
AECOM identified approximately 260 confirmed or suspected wells within the search area. Though
most are suspected, at least 56 wells were positively identified based on previous environmental
investigations (reports dating back as far as the early 1990s), well construction diagrams, and/or
laboratory data since 2010. Well locations are shown in Figure 3.1. Well locations are considered
approximate, since location information is largely based on a parcel system, and does not necessarily
reflect exact coordinates. There are 23 confirmed and 226 suspected wells within a two-mile radius of
the site, based on GSV observations.
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3.1.2 SRK Groundwater Well Inventory
SRK completed a review of the available information to identify the presence of groundwater wells
within a 2-mile radius of the Archdale facility, 4-mile radius of the Kings Mountain facility, and the
extents of the regional boundary used in the November 2023 numerical groundwater model efforts.
The scope of the survey consisted of using the following to develop this dataset:
• North Carolina Public Water Supply Water Sources (https://nconemap.gov)
• United States Geological Survey Mineral Resource Online Spatial Data (https://
mrdata.usgs.gov)
• National Groundwater Monitoring Network (https://cida.usgs.gov/ngwmn/index.osp)
• South Carolina Coastal Plain Water Well Database (https://hVdrologV.dnr.sc.gov/well-
database.html)
• AECOM Water Supply Survey and Well Construction Information (AECOM, August 22, 2022)
• Site reconnaissance of the Archdale Facility (2023)
• Site reconnaissance of the Imerys Facility (wells, 2023)
In reviewing the available data for the Archdale hydrocensus, SRK identified additional wells within the
AECOM Kings Mountain hydrocensus 4-mile search radius and within the boundary of the 2023
regional numerical groundwater model. Table 3.1 shows the potential well locations within the
Archdale 2-mile radius, the Kings Mountain 4-mile radius, and the 2023 groundwater regional model
boundary. SRK identified 102 additional wells in the Kings Mountain 4-mile radius in addition to the
294 wells found by AECOM. SRK identified 157 suspected wells within the 2-mile radius surrounding
the Archdale tailings facility. Within the 2023 regional groundwater model boundary, SRK identified an
additional 308 suspected wells, for a total of 602 suspected wells in the 2023 regional groundwater
model. Figure 3.2 shows the suspected well locations.
Table 3.1: Potential Wells within the Archdale 2-Mile Radius, Kings Mountain 4-Mile Radius,
and 2023 Regional Groundwater Model Boundary
Boundary Program Type Wells
AECOM 2022 Google Street View 7
Online 8
Archdale Google Street View 126
2-mile SRK 2023 to 2024 Online 2
radius
Site reconnaissance 14
Total suspected wells 157
AECOM 2022 Google Street View 53
Online 241
Kings Mountain Google Street View 66
4-mile SRK 2023 to 2024 Online 13
radius Regional data search 9
Site reconnaissance 14
Total suspected wells 396
AECOM 2022 Google Street View 53
Online 241
2023 regional Google Street View 126
groundwater SRK 2023 to 2024 Online 140
model Regional data search 28
Site reconnaissance 14
Total suspected wells 602
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Figure 3.2: Archdale/Kings Mountain Hydrocensus Overview
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3.2 Hydrogeologic Characterization Program
3.2.1 2018 to 2022 Field Characterization Program
SRK(2023b)details the results of the Kings Mountain Hydraulic Characterization report. SRK collected
opportunistic hydrogeologic data during an exploration drilling program in 2018. Although the
exploration program did not target hydrogeologic characterization specifically, insight gained from
hydraulic testing and monitoring equipment installations during that program significantly advanced
the understanding of the groundwater system in the Project area. This program included packer-
isolated interval testing, vibrating wire piezometer(VWP) installations, and construction of water level
monitoring equipment using open diamond core holes and existing wells (stub wells and VWPs). Data
loggers were installed to record water level data from select stub wells, all VWP's, existing wells, and
pit lake. Two barometric pressure transducers were installed in the southern end of the pit and at the
north wall.
The second half of 2022 saw the commencement of a pre-feasibility hydrogeologic characterization
program, developed by SRK starting the year prior, to evaluate the shallow and deep groundwater
systems. In addition, a geotechnical characterization program, targeting tailings and RSFs, was
included in this scope of work to expand data collection across the site. The field program consisted
of monitoring well installation screened across the overburden (native, tailings, and waste rock),
saprolite, weathered bedrock, and terminating in competent unweathered bedrock to evaluate the
shallow groundwater system. Monitoring wells were installed to evaluate the deep groundwater system
by drilling across the overburden sequence and into competent bedrock, to depths greater than 500
feet below ground surface (ft bgs). Additional larger diameter pumping wells were installed to stress
the shallow groundwater system. Pumping tests were performed, lasting up to 7 days. Spinner logging
was performed in all accessible wells to identify water-producing zones and to calculate the distribution
of transmissivities throughout the screen or open hole intervals.
Between 2018 and 2023, hydrogeological data were collected from a total of 104 boreholes, with
combined total drilled length of 46,280 ft. Figure 3.3 shows the drilled borehole locations.
CB/GE KingsMountain_Archdale Well M itigation Plan_Report_USPR000576_Rev03.docx April 2024

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SRK Consulting(U.S.), Inc.
Water Supply Well Mitigation Plan—Kings Mountain Page 9
3.2.2 2023 Field Characterization Program
The Archdale Hydrogeologic Characterization Report is detailed in SRK (2024). SRK collected
opportunistic hydrogeologic data during a geotechnic drilling program in 2023 both on TSF and Project
sites. The geotechnical characterization program was performed to expand the geological and
geotechnical understanding of the existing RSFs and TSFs at the Kings Mountain Mine Site and the
proposed Archdale tailings facility. The geotechnical field program consisted of drilling boreholes
across the overburden layers into competent bedrock. In certain locations, monitoring wells were
installed into the borehole and were screened across the water table. In wells installed on Archdale,
hydraulic testing was conducted via slug testing in the individual wells as well as one large pumping
test across the site. The pumping test was performed by pumping from the pit lake for approximately
5 days and monitoring drawdown in both the pit lake and all wells on-site.
During the 2023 field season, 34 boreholes were drilled at Kings Mountain (with a combined total of
4,380 ft), and 13 groundwater wells were installed. At the Archdale tailings facility, 11 boreholes were
drilled (for a combined total of 1,005 ft), and 10 groundwater wells were installed. Figure 3.4 shows
the drilled borehole locations across both Kings Mountain and Archdale sites.
CB/GE KingsMountain_Archdale Well M itigation Plan_Report_USPR000576_Rev03.docx April 2024

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SRK Consulting(U.S.), Inc.
Water Supply Well Mitigation Plan—Kings Mountain Page 11
3.3 Conceptual Groundwater Model
3.3.1 Kings Mountain
The conceptual hydrogeologic model is detailed in SRK (2023a) and summarized on Figure 3.5. In
general, the groundwater system is conceptualized to include two main components, namely, the
surface regolith and deeper bedrock.The surface regolith is the more conductive portion of the system
(hydraulic conductivities ranging from 0.1 to 0.5 ft/day), being composed of overburden, saprolite and
weathered bedrock. Most of the drawdown related to mining, both legacy and proposed, is understood
to occur in the surface regolith. The legacy recovery of the pit lake is also believed to be mainly
supplied by recharge from precipitation, which flows through the regolith to the groundwater.
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SRK Consulting(U.S.), Inc.
Water Supply Well Mitigation Plan—Kings Mountain Page 12
71
,.-- y,
Kegol;rn r
Muscorite Scict I
I
Philitic Metasilstone
Shear one units
Propcsed oom , T lYd[er Table 2n23 __'_Water�_o�e 2035
5] Recharge:30 years average precipitation recorded as 46 inlyr(PRISM). I ————————————
(3) Kings Mountain Open Pit:Lake fanned after the end of the historic mining Basefle•;3na•ses suggested that 12-20%of this amount enters the If 1
per'ec;19941.It-e•=c•ve red to 820ft asl approxim •:
ately in 20 years.The bottom groun .:3:= --,,stem as recharge,and discharges to surface water and lakes.
m:=cl,ci t c i c-:h e rechar is assumeo follow deeper flow path in I w j""O1iE
c-:I-e e•:i=:•-Ia.e i_563 it asl.Inflow to the previous operation was A I i d t fll d er p jf,a.ry -Z. we.m.en
ca•-u ate-3-3 cr low pe•q-eahle bedrock.
(21 Martin hlai ietta quarry Lc cite:in low permeability Marble Unit.The water 6) Regolith:Consists of soil,'c.r oe•mea 'e s-piolite,and relatively permeable I ve -
weat-ered zone.The test s..ggests le-9—i--d zone K as:0.1-3-5 ft/day. I r prol
z � tie:r 3'I be atzd-�;�= •-reg. byte current operation at around 620 ft
a-1.`.c see:aae i.as o13se-ved a 1:i:',:a -,s_gg esti ng a low-permeability Spi r-er I =_g_g as cc-•:.c-ed to a:.I:Iore-I-e oresence of a transition zone
se tting•.:it- --��: -tz a=:- tie KI•A lake. betv.ee i e ce:lr.-•• ere the weatherec zone.These tests reveal that the I wr..c,uxnx
31 Water table 2023 T-e ex st i-,• Ia<- -I ns thesha a of the current tran,iYo-are-as a :ec extent,is spa-se and is not co--ected. I _ s�erlarrr
3:-,:able--e l:i--.3<e r3s e•ed tie pre-mining water level in nearby 7] Bedrock hydraulic conductivity:f K] Is ce:ein-ir ec v a corm:•ehensive aquifer
:el`--cler 3id,i, tests.Tests=ugges:-•=st1•; .: to n-e:..�•a-ge ._3-4ft:.•::c 3.3 ft/day).
c I..er-•a-u�ed.one. I �u:na"r
(4) Water Table 12033j:Pi-• 3s-c ccen pit will Ic-aer the water to ble to 285 ftasl Packer tesc pre-- -g ir�wcat=_cl--at K--a—r:it-caper c..e co the absence
at a center•==the t.-His%;11 c•e3:e a:c it•:-a bit nisi--cl cl 3•_o.cm to of fracture. I Hamed and
nearby weathered and upper fra-turz units as these zonzs arz readily ac ou ea s an or wes ncrease
8] Shear Contact Zones IStht d Ntht):Asl ightly id Daniel,1992
I I
impacted by the current lake level. lineament was d—i-•ecl clu ira'eld characterization.Shear Contact zone K -- ——————————————
is determined r i the•a-ge .2-1.5 ft/day
Figure 3.5: Conceptual Hydrogeologic Model of Kings Mountain Pit Area
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SRK Consulting(U.S.), Inc.
Water Supply Well Mitigation Plan—Kings Mountain Page 13
By contrast, the deeper bedrock is less conductive than the surface regolith (hydraulic conductivities
ranging from 1x10-4 to 0.3 ft/day). In addition, hydraulic conductivity in the bedrock decreases as depth
below surface increases. Flow in the bedrock is expected to occur primarily through fractures, which
are mostly present in shallower depths closer to the weathered zone. Therefore, mining operations
are less likely to affect groundwater levels in the deep bedrock than in the overlying regolith.
In addition to these components, hydraulic testing identified two major water-bearing lineaments in the
bedrock, at geological contacts east and west of the Kings Mountain pit. These lineaments have been
labeled the Southeast and Northwest Shear Contact Zones, respectively, and have shown hydraulic
conductivities similar to, or higher than, those observed in the regolith.
A fraction of precipitation percolates through the different regolith units and recharges the groundwater
system. In the bedrock system, recharge occurs mainly through fractures and the weathered zones of
the intact rock. A limited portion of the recharge is assumed to follow a deeper flow path in low-
permeability bedrock. Recharge varies spatially based on local soil conditions and level of
urbanization.
Outflow from the groundwater system follows a regional path or a local discharge path to creeks and
streams from shallow groundwater. In the area of the pit lake, groundwater generally flows from the
northwest to the southeast. Around the Kings Mountain Project and nearby Martin Marietta pit, the
water table has been affected by legacy mining, exhibiting concentric flow towards the excavations,
as shown on Figure 3.6. The Kings Mountain pit lake levels have been historically lower than
surrounding groundwater levels, indicating discharge from the groundwater system to the lake.
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SRK Consulting(U.S.), Inc.
Water Supply Well Mitigation Plan—Kings Mountain Page 14
1293000 1294500 1296000 1297500 1299000 1300500 1302000
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Y srk consulting WATER SUPPLY WELL MITIGATION PLAN
,t],JGS MOUNTAIN MINING PLAN
AA L B E MA R L E Kings Mountain Potentiometric Sur-Face IEEOEOFDR Albemarle corporation
--CE.SRK.2023 oa-e04)2023 FIDUREND.:FIGURE 3.6
FILE NAME: SRKJD9 Nl1 E-USPR000576
Figure 3.6: Kings Mountain Potentiometric Surface
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SRK Consulting(U.S.), Inc.
Water Supply Well Mitigation Plan—Kings Mountain Page 15
3.3.2 Archdale
Figure 3.7 summarizes the conceptual hydrogeological model for the Archdale tailings facility detailed
in SRK (2024). The conceptual hydrogeologic model describes the understanding of the inputs,
outputs, and movement of groundwater in the model domain. Available data indicate the overburden
has been mostly mined out at the proposed Archdale tailings facility, and some pit lakes have formed
in the formerly mined areas. The water table is above the bottom of the existing pit lakes (Figure 3.8).
Since the pit lakes at the Archdale facility are likely in contact with the groundwater, any tailings
deposited in the pits will be in direct contact with the groundwater system.
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SRK Consulting(U.S.), Inc.
Water Supply Well Mitigation Plan—Kings Mountain Page 16
Lithology
Overhurden
saprolite
- Weathered bedrock
Discharge Mica schist
1 I�
s �� �t T `-��► x=0.04ft/d
Groundwater - --- ------- x=O fJdII II _I...wrn—
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(1) Panda:Pit lakes formed during the previous mining period 4) Evaporation and Discharge from the pit lake:The pit 1
2014.The water level is being regulated at an elevation of lake e:a oraricn is ass_.-red to he 42 in/vr SRK,2023.
( } g g I l ) 1
around 845ft. A pump idlsche ge z-ructure vdasto..nd a-t•e slte It is 1 1
(2) Recharge:32 year average precipitation was recorded as 42 envisio�uc that the 1Nater le•-:el at the o f ake is I -'
In/yr(NOAA,2023).Recharge calibrated to groundwater regula-ed via this pump.Currently,the pumping rate is ll
levels suggests an average of 6 in/yr enters the groundwater unkno:.n.
system as recharge(14%of MAP)and discharges to surface 5) Regolith:Consists of soil,low permeable saprolite,and L — — — — — —
water and lakes.A limited portion of the recharge is relay:a Named and Daniel,1992
p g y permeable weathered bedrock.Slug testing
assumed to follow a deeper flow path in low-permeability suggests weathered zone K ranges from 0.01 to 1 ft/d.
bedrock. 6) Bedrock hydraulic conductivity:(K) Is determined via
(3) Watertable(2024):The existing pit lake elevations govern aquifer tests at the Kings Mountain site Tests suggest
the shape ofthe curie t.vater-able.-he )t lakes ha.:e mostlf lo,v to medium arge ;lE-4 f=/d to 0.1=t/d}.
lowered the ore-miring:eater level In rearby c.erLrurden Packer test o ofiling indicated.hat K decreases with
and..:)pe:fractured zone.Grounc:;a-e fl-;:s rnam y depth aue to the apse•ice of fracture.
towa dsthe pond,except n t-e south:,,�es-of-he deeper
pond,where there is no data to e,alua.e the direction of
groundwater flow.
Y srk consulting WATER SUPPLY WELL MITIGATION PLAN
KINGS MOUNTAIN MINING PROJECT
AA L B E M A R L E —-- REVIEVE°9Y W Archdale Conceptual Groundwater Model a oece Albemarle Corporation
—SRK,2023 —0312024 F,� FIGURE 3-7
ALE NAME 06 Section Flgures.ppix SRK JC9 NUMBER.USPROD0676
Figure 3.7: Hydrogeological Assessment Study for Archdale Tailings Facility
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SRK Consulting(U.S.), Inc.
Water Supply Well Mitigation Plan—Kings Mountain Page 17
128 128' 1281— 1281—
ry
201OH1067M 201OH1069M
875.7 ft 0903.4 ft
O
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891.4.4 It ft
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201OH1070M SNKM23-529 906.5 ft
889.0 ft 896.4 ft
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898.6 ft/884.0 ft
• KW-04 0 KW-09
881.8 ft SNKM23-540 882.9 ft
867.1 ft .SNKM23-511
„ 876.2 ft
SNKM23-557
201 OH1074M 850.5(t
902.8 ft n
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866.9 ft
KW-01/
860.5 ft
SNKM23-531 l
SNKM23-548 847.3 ft 3
875.4 ft
•KW-07 ha`
KW-11 866.1 ft
868.6 ft
SNKM23-541
870.6 ft
MEASURED GROUNDWATER ELEVATION JAN 2024(It amyl)
Hlstoriral Wells
. 2023 Wells
PR Lake B thy—try(ft amsl)
Groundwater Elevation(ft amsl)
—► Groundwater Flow pirectlon =
0 206 400 600. 800 ION
Property Boundaries
Feet
NM JW SYelePlure Na C M—FleS 32DW Fmi
=$=srk consulting DRAFT POTENTIOMETRIC SURFACE
DRAWN By Agp REVIEWED ev: GE A A L B E M A R L E ]iYOROGEOLOGICAL ASSESSMENT STUDY.
ARCHDALE TAILINGS FACILITY
souRCE SRK2024 DATE: 0312024 KINGS MOUNTAIN MINING PROJECT 111,uREH11: 3-5
rIIF Rune.Fig S5 PDteml—ftic Sudece USPRN 0000576
Figure 3.8: Archdale Potentiometric Surface
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SRK Consulting(U.S.), Inc.
Water Supply Well Mitigation Plan—Kings Mountain Page 18
4 Impact Assessment
4.1 Numerical Groundwater Model
4.1.1 Kings Mountain
SRK developed the numerical groundwater model for the Project using the MODFLOW-USG control-
volume finite-difference code (SRK, 2023d). The numerical model used an unstructured grid
formulation with Voronoi polygons and was designed to estimate groundwater inflow to the proposed
open pit, pit lake recovery following mining operation, water level changes and impact to the
groundwater system during proposed mining and post-mining conditions. The numerical model
incorporated 13 major hydrogeological units that were identified in the geological model (further
subdivided to 32 hydrogeological units) and simulated recharge from precipitation and proposed
mining facilities, interaction with surface-water bodies, excavation of the pits and pit lakes infilling(both
legacy and proposed).
SRK calibrated the numerical model to legacy inflows and pit lake water levels, baseflow estimates in
creeks and groundwater levels (including responses to long-term pumping tests). According to SRK's
assessment, the model effectively replicated both past and present conditions. Calibration to
groundwater levels resulted in a normalized root mean square of less than 10%. Simulated deviations
from measured baseflows ranged from 1% to 5%. These error rates are considered acceptable when
compared to industry standards. The calibrated numerical model was used to predict changes to
hydrological conditions, including inflow to the proposed pit and the propagation of drawdown.
In summary, the completed hydrogeological study successfully employed geological data, field
investigations, and the development of a 3-D numerical groundwater model to comprehensively
understand and predict the interactions between mining activities and the groundwater system. The
findings of this study will provide crucial information for effective management and mitigation of
potential impacts to the groundwater system, ensuring sustainable mining practices and the protection
of nearby wells.
4.1.2 Archdale
The Archdale groundwater model is a window, or site-specific model, within the regional Kings
Mountain groundwater model based on extensive characterization. The window model was designed
to estimate dewatering rates for the existing pit lakes on site, seepage from the proposed TSF and
embankment into the drainage system during tailings deposition, and seepage from the proposed TSF
and embankment into the groundwater system after completion of tailings deposition. The Archdale
site-specific model uses the results of the regional model as boundary conditions and simulates similar
geologic structures and units as the regional model. However, the Archdale site-specific model grid
was refined, and the hydraulic parameter distribution was revised to reflect the results of field
investigations at the Archdale site. Refinement and revision of the regional model was necessary to
simulate the interaction of the TSF with the groundwater system in sufficient detail to provide
reasonable inputs to the surface water and geochemical models.
The site-specific numerical groundwater model was developed using MODFLOW-USG. The
Groundwater Vistas graphical user interface (Version 8) was used for pre- and post-processing
(Environmental Simulations, Inc. (ESI), 2020). MODFLOW-USG is a version of the groundwater flow
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SRK Consulting(U.S.), Inc.
Water Supply Well Mitigation Plan—Kings Mountain Page 19
code MODFLOW that uses unstructured grids. An unstructured grid formulation provides flexibility to
a MODFLOW simulation by enabling localized refinement or coarsening of the model domain grid.
Flexibility in grid design enables adjustment of grid cells to conform to small-scale features, such as
creeks and faults. MODFLOW-USG also provides mass-conserved, robust, and efficient numerical
solutions without the computationally intensive numerical integration, elemental assembly schemes,
and expanded matrix connectivity associated with finite element methods. The Archdale site-specific
model uses an unstructured grid with a quadtree refinement scheme to represent small-scale details
on-site, with larger grid cells near the boundaries.
4.2 Expected Groundwater Level Change
4.2.1 Kings Mountain
The numerical groundwater model was used to evaluate the impact of proposed mining on
groundwater levels and nearby surface water features. Full details of the analysis are given in SRK
(2023). Figure 4.1 shows drawdown impacts.
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SRK Consulting(U.S.), Inc.
Water Supply Well Mitigation Plan—Kings Mountain Page 20
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SRK Consulting(U.S.), Inc.
Water Supply Well Mitigation Plan—Kings Mountain Page 21
Open pit excavation and associated dewatering will alter the groundwater level around the open pit.
As shown on Figure 4.1, no wells outside the Project boundary are predicted to be impacted by
groundwater level change.
The model predicted the following under calibrated Base Case:
• Groundwater inflow rates to the proposed pit in the range of 100 to 270 gpm.
• Maximum 5-ft drawdown extent of 0.29 miles to the southeast, 0.2-0.3 miles to the northwest
and northeast, and 0.97 miles to the southwest. The maximum drawdown extent in various
directions will occur at different times, from approximately 11 to 30 years after end of mining.
Results of the numerical groundwater modeling indicate that impacts related to the reduction in
groundwater levels are expected to be minimal outside the site boundary as a result of dewatering and
mining operations.The maximum extent of the 5-ft cone of drawdown remains mostly contained within
the site boundary. Unless otherwise agreed by potentially affected stakeholders, water resources
affected by mining activities will be maintained at quantities that enable continued use of those
resources for current purposes and for potential future uses to be identified in collaboration with
relevant stakeholders. The content of this section may be further developed as more information
regarding wells becomes available following the extensive hydrocensus (well inventory) study that is
being planned (see Section 5.1).
4.2.2 Archdale
The numerical groundwater model was used to evaluate the impact of proposed pit dewatering and
mining operations on groundwater levels surrounding the Archdale tailings facility. Groundwater
drawdown due to pit lake dewatering is limited due to the short duration of pumping and the relatively
low permeability of the saprolite beneath the pit lakes. Figure 4.2 shows the maximum extent of the
5-foot drawdown contour. On the east side of the Archdale area, a small wetland area is simulated by
the model during steady state. The simulated head in the wetland is reduced during dewatering, so
there is a small amount of drawdown to the east of the main pit lake. The maximum drawdown occurs
a few months into tailings deposition (early in operation), after which water levels begin to rise due to
the removal of the pit lakes as sinks.
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SRK Consulting(U.S.), Inc.
Water Supply Well Mitigation Plan—Kings Mountain Page 22
12 120• 1 ta— 120— ua-•
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t ..
— Predicted Extent of 5-Ft praw&N;n Conti �t Cra = 40
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42
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Figure 4.2: Predicted Extent of 5-Foot Drawdown Contour Resulting from Pit Lake Dewatering
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SRK Consulting(U.S.), Inc.
Water Supply Well Mitigation Plan—Kings Mountain Page 23
5 Baseline Data and Predictive Tools Improvement
5.1 Update of the Groundwater Well inventory
As outlined in Section 2.1, AECOM has undertaken a groundwater well inventory analysis aimed at
identifying users of wells and their usage networks. Although this study offers valuable insights into
the population of groundwater wells and current water usage within the project's vicinity, it lacks the
specific details necessary for the development of a comprehensive mitigation plan.
Before commencing the project, Albemarle will collaborate with DEQ to conduct an extensive
hydrocensus (well inventory) study to enhance the foundational data for the subsequent mitigation
analysis. The study update will focus on:
• Well Users: Ownership status of the well.
• Well Location: Determining the precise geographical coordinates of groundwater wells in the
study area.
• Well Depth: Measuring the total depth of each well to assess the level at which groundwater
is being intercepted.
• Well Construction: Examining the construction details of each well, including casing materials,
screen lengths, and seal depths, which can impact the well's efficiency and vulnerability to
contamination.
• Water Quality: Analyzing water samples from the wells to assess groundwater quality,
including parameters such as pH, turbidity, total dissolved solids (TDS), and the presence of
contaminants or pollutants.
• Water Quantity: Measuring and recording the water level or water table in each well at various
times to understand fluctuations and seasonal variations.
• Pumping Rates: Monitoring the rate at which groundwater is being pumped from each well to
determine the extraction volume and the effect of pumping on water level change(drawdown).
• Water Use: Identifying the purpose of water use for each well, whether it's for agricultural
irrigation, industrial processes, municipal water supply, or other purposes.
• Dependency on Wells: Assessing the extent to which the local community or various sectors
rely on groundwater wells for their water supply needs.
• Well Maintenance: Inspecting the condition of each well and assessing the need for
maintenance or rehabilitation to ensure continued functionality.
5.2 Monitoring Network
Groundwater levels have been monitored at the site since 2018 (SRK, 2023a). The current available
groundwater monitoring network includes:
• 19 open diamond core holes equipped with surface casing and left open to the final depth
drilled.
• 15 stub wells installed in selected open holes for long-term water level monitoring (a stub well
is constructed by lowering well casing up to 2-inch diameter, equipped with a cement basket
attached at the bottom into competent bedrock ranging in depth from 30 to 100 ft below ground
surface [bgs]).
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Water Supply Well Mitigation Plan—Kings Mountain Page 24
• 4 pumping wells, 2 deep monitoring wells (greater than 400 ft deep), 45 monitoring wells, and
1 temporary well.
• 7 Legacy wells on Archdale and 7 legacy wells on the property to the north of the site
• 5 grouted-in-place VWPs
Existing groundwater monitoring network will provide opportunity to monitor baseline conditions. For
the well supply mitigation plan, 10 of the existing wells will be instrumented to collect water level data
continuously. Additional five wells will be drilled and instrumented to establish full coverage to verify
the extent and amount of drawdown produced by pit dewatering. Figure 5.1 shows the locations of the
existing water level monitoring wells.
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oW5 e
Figure 5.1: Available Groundwater Monitoring Network Locations
5.3 Predictive Tool Updates
The numerical groundwater model will be updated regularly during the life of mining. After the end of
pit lake dewatering, model predictions will be re-evaluated, and any necessary model updates will be
made.After the start of mining,the model will be updated every 2 years or as new water level and flow
measurement data are collected.
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6 Trigger Action Response Plan (TARP) Development
The Project's potential water impacts on quality and quantity will be scoped during future studies based
on applicable national and international standards. The Well Supply Mitigation Plan will include
indicators/triggers related to environmental and social impacts or risks and updated based on results
of future studies.
The Plan will:
• Specify numerical criteria that would serve as Trigger Action Response Plan (TARP) alerts.
The TARP criteria would pertain to groundwater levels and groundwater quality indicators.
• Outline planned actions to mitigate or further assess predicted impacts to current and future
uses of water and natural resources from changes in groundwater quality and quantity
throughout the life cycle of the proposed mining project. These would include unintentional
releases from tailings or other mine waste facilities, and account for indirect impacts from
climate change.
• Specify steps to be taken if trigger levels are exceeded.
• Include timelines for completion of actions and assign actions to responsible parties.
• Include estimates of required human resources and budget, and financing plan where
relevant, for effective implementation of the plan.
Efforts to identify groundwater users who may be impacted are ongoing at this time. Though
community wells have been identified, it is unclear if those wells are in use. Therefore, the content of
the Plan may be further developed as more information regarding wells and impacted users becomes
available following the extensive well inventory study that is being planned. Water level mitigation may
be triggered if water levels outside the predicted maximum 5-ft cone of drawdown demonstrate a
decreasing trend. Trend analysis will be conducted using appropriate statistical methods for the
dataset.Additionally, if water level drawdown at any location exceeds expected drawdown,water level
mitigation may be triggered. Further investigation will be conducted to determine whether decreasing
trends or excess drawdown are the result of changes in precipitation; changes in nearby water use
patterns (such as reduction in outflow from the nearby Martin Marietta pit); or impacts from the
proposed mining. If mining is determined to be the cause of the decrease in groundwater levels,
mitigation will be undertaken. Mitigation may consist of deepening existing community wells, drilling
deeper community wells or providing alternative water to individuals (municipality supply system).
Options to mitigate predicted water impacts on quality and quantity will need to be evaluated in
collaboration with stakeholders, including regulators, in a manner that aligns with the mitigation
hierarchy.
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Table 6.1: TARP Example
Trigger Response Action Plan
Trigger Level Description Trigger Triggers Response
Level
Water level departure from model 1 Detected difference Check model calibration and
predictions >5 ft seasonality impact
Water level drop in monitoring well 2 Detected difference Increase monitoring and data
within project boundary >5 ft review frequency, evaluate
model sensitivity
Change in water level trend 2 Month long decline Increase monitoring and data
in measured water review frequency, evaluate
level trend from model sensitivity to reduced
previous precipitation local to the well
measurements
Reported decline in nearby Public 3 Stakeholder Check monitoring point
Wells engagement, behavior at monitoring wells,
compliance initiate well survey, provide
temporary water for
irrigation/drinking
Confirmed decline i 4 Stakeholder qV Initiate well deepening
Wells engagement, procedures, new well
compliance installation and improve water
supply infrastructure
Predicted groundwater level changes based on the numerical groundwater model are shown across
Appendix A. Actual water level change will be compared to predicted change on a quarterly basis for
model reliability and verification. Observed changes that demonstrate trends outside of the predicted
range may trigger a water level mitigation investigation. Note the model incorporates inherent error
with respect to groundwater levels and therefore requires field program to ground truth model
predictions.
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7 Stakeholder Engagement
In general, ERM's studies are driving most stakeholder engagement activities for the Project.
Therefore, this plan provides limited stakeholder engagement provisions for SRK.
7.1 Current Engagement Status
SRK's main stakeholder engagement activities associated with the development of this Well Supply
Mitigation Plan to date include the DEQ Meetings and community updates. Records of these activities
are provided below:
Table 7.1: Summary of SRK's Stakeholder Engagement Activities
Date Stakeholder Format Scope/Objectives
July 27, 2022 DEQ Presentation Communication of hydrogeology(groundwater)field
work plans
Hydrogeology progress update, including summary
May 18,2023 Community Presentation of characterization and models, preliminary findings,
and proposed monitoring program
Hydrogeology progress update, including summary
June 01, 2023 DEQ Presentation of characterization and models, preliminary findings,
and proposed monitoring program
7.2 Future Engagement Roadmap
SRK will continue to engage with the community and regulatory authorities regarding hydrogeology
progress updates, if needed.
Throughout the Project and as part of any future updates to this Plan, Albemarle will continue to
engage with stakeholders, including regulatory authorities, community members and organizations,
nearby water users, and owners of adjacent properties. The Plan's most recent versions and all
updates will be publicly available, or Albemarle will have a policy in place to make the information
available to stakeholders upon request.
Summary of the findings of monitoring will be made publicly available at least annually, and all data
and methodologies related to monitoring completed by Albemarle and its contractors will be publicly
available either on the internet (e.g., via Albemarle's website), at a public location (such as a library,
government office, community center, etc.), or upon request from Albemarle. The following water data
will be monitored and published annually, or at a frequency agreed by stakeholders from affected
communities: i)monitoring data for groundwater points of compliance; and ii)monitoring data for water
quantity (i.e., groundwater levels).
Community stakeholders will be provided with the opportunity to review, comment, and participate in
the revision of the Plan. Water management strategies, performance and adaptive management
issues will be discussed with relevant stakeholders on an annual basis or more frequently if requested
by stakeholders. Further stakeholder consultation, including with regulators, might be required to
evaluate mitigation options in line with the mitigation hierarchy.
A more detailed Stakeholder Engagement Plan regarding the Project's broader environmental and
social impacts will be developed by ERM as part of the ongoing evaluation process. The Stakeholder
Engagement Plan will delineate the engagement requirements and means, including but not limited to
the establishment of a grievance mechanism to ensure stakeholders' grievances regarding potential
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groundwater issues are effectively collected and addressed. This Plan will be revised in accordance
with the Stakeholder Engagement Plan and the identified trigger levels. It will include procedures for
rapidly communicating with stakeholders in case of changes in water quantity or quality that could lead
to compliance issues or trigger stakeholder engagement. This will cover any reported or confirmed
decline in nearby public wells, among other trigger levels. These procedures will also be incorporated
into relevant emergency response plan(s).
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8 Well Mitigation Update Schedule
This Well Supply Mitigation Plan will be reviewed and updated as new information becomes available
or if there are any changes to the mine plan, regulatory context, or the environment. Albemarle will,
annually or more frequently, if necessary, review and assess the efficacy of the Plan and adaptive
management actions revise the Plan to improve water management outcomes as necessary.The Plan
will be updated annually after pit dewatering begins, with reference to the groundwater level
monitoring.
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9 References
AECOM, 2022. Water Supply Survey and Well Construction Information. Technical Memorandum
dated August 9, 2022 to Albemarle.
Albemarle Corporation (Albemarle), 2023. Albemarle 2022 Sustainability Report. Published June 4,
2023. https://www.flipsnack.com/A798C777C6F/albemarle-2022-sustainability-report.html.
Environmental Simulations, Inc. (ESI), .2020. Guide to Using Groundwater Vistas, version 8, code
documentation report. Reinholds, PA: Environmental Simulations, Inc.
Garrett, 2004. Please provide this reference.
Horton and Butler, 1988. Please provide this reference.
RK Consulting(U.S.), Inc. (SRK), 2022. Development of Stage Discharge Relationship for South Creek
Outlet Culverts and No. 3 Weir,technical memorandum prepared for Albemarle, September 27, 2022.
SRK, 2023a. Technical Report: Prefeasibility Study, Hydrogeologic Characterization Kings Mountain
Mining Project: report prepared for Albemarle, May 12, 2023.
SRK, 2023b. Technical Report 2022 Prefeasibility Study Surface Water: Water Balance Development
Report: report prepared for Albemarle, May 17, 2023.
SRK, 2023c. Interim Geochemical Characterization Report for Kings Mountain Waste Rock, Ore and
Tailings, In Progress 2023.
SRK, 2023d. Technical Report 2023 Prefeasibility Study, Hydrogeological Study and Groundwater
Modeling Kings Mountain Mining Project, September 15, 2023.
SRK, 2024. Hydrogeological Assessment Study for Archdale Tailings Facility Kings Mountain Mining
Project Prefeasibility Study, April 5, 2024.
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Disclaimer
The opinions expressed in this Report have been based on the information supplied to SRK Consulting
(U.S.), Inc. (SRK) by Albemarle Corporation (Albemarle). These opinions are provided in response to
a specific request from Albemarle to do so, and are subject to the contractual terms between SRK and
Albemarle. SRK has exercised all due care in reviewing the supplied information. Whilst SRK has
compared key supplied data with expected values, the accuracy of the results and conclusions from
the review are entirely reliant on the accuracy and completeness of the supplied data. SRK does not
accept responsibility for any errors or omissions in the supplied information and does not accept any
consequential liability arising from commercial decisions or actions resulting from them. Opinions
presented in this report apply to the site conditions and features as they existed at the time of SRK's
investigations, and those reasonably foreseeable. These opinions do not necessarily apply to
conditions and features that may arise after the date of this Report.
Copyright
This report is protected by copyright vested in SRK Consulting (U.S.), Inc. It may not be reproduced
or transmitted in any form or by any means whatsoever to any person without the written permission
of the copyright holder, SRK.
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Water Supply Well Mitigation Plan—Kings Mountain Appendices
Appendices
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Water Supply Well Mitigation Plan—Kings Mountain Appendices
Appendix A: Predicted Water Level
Changes at Monitoring Locations
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Water Supply Well Mitigation Plan—Kings Mountain Appendices
Monitoring Well 1 Monitoring Well Monitoring Well 3
-20 -20 1 1 -20
-15 16-15 -15
o-10 c_.10 c_-10
IF
3 -5 �1 ; -5 ; -5 —
0 0 0
9
3 0 # 0 3 0
N
y 5 5 5
L b
V 109 109 10
i 15 a 15 a 15
20 20 20
0 1 2 3 4 5 6 7 8 9 10 0 1 2 3 4 5 6 7 8 9 10 0 1 2 3 4 5 6 7 8 9 10
Years since start of mining Years since start of mining Years since start of mining
Monitoring Well Monitoring Well 5 Monitoring Well
-20 -20 -20
w-15 Note larger stale for Moaitoring Well 5 'a-15
A 0
e-10 c-10
3 5 3 20 3 -5
9 9
� o � ao a
0 5 a` 0 5
-o y 60 m
9 10 -o _ 1a
n 15 80 a 15
20 100 20
0 1 2 3 4 5 6 7 8 9 10 0 1 2 3 4 5 6 7 8 9 10 0 1 2 3 4 5 6 7 8 9 10
Years since start of mining Years since start of mining Years since start of mining
Monitoring Wall Monitoring Well 6 Monitoring Well
-20 -20 -20
m-15 u-15 m-15
-10 -10 -10
-5 G -5 3 -5
# 0 3 0 # 0
9 5 0 5 9 5
V 10 u9 1U S 10
6 15 1 15 a• 15
20 20 20
0 1 2 3 4 5 6 7 8 9 10 0 1 2 3 4 5 6 7 8 9 10 0 1 2 3 4 5 6 7 8 9 10
Years since startof mining Years since startof mining Years since start of mining
Figure A.1: Predicted Drawdown in Proposed Monitoring Wells during Mining Period (Wells 1 through 9)
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Water Supply Well Mitigation Plan—Kings Mountain Appendices
Monitoring Well 10 Monitoring Well 11 Monitoring Well 12
-20 -20 -20
y-15 y-15 y-15
c-10 c-10 c-10
b � b
5 5 9 5
a
- 10 r-' 10FJ
- 10
n 15 n 15 — n 15 —
:::]20 20 20
0 1 2 3 4 5 6 1 8 4 10 0 1 2 3 4 5 6 7 8 9 10 0 1 2 3 4 5 6 7 8 9 10
Years since start of mining Years since start of mining Years since start Of mining
Monitoring Well 13 Monitoring Well 14 Monitoring Well 15
-20 -20 20
15 -15 15
c-10 c-10 c-10
c c c
0 o a
v a v
3 0 3 0 3 0
8 � 8
9 5 L 5 9 5
10 10 1a
a` 15 n 15 I a` 15
20 20 L 20
0 1 2 3 4 5 6 7 8 9 10 0 1 2 3 4 5 6 7 8 9 10 0 1 2 3 4 5 6 7 8 9 10
Years since start of mining Years since start of mining Years since start of mining
Figure A.2: Predicted Drawdown in Proposed Monitoring Wells during Mining Period (Wells 10 through 15)
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