TM_PiedmontLithium_Groundwater Model_20190702

Technical
Memorandum
Groundwater Model
Piedmont Lithium
Gaston County, North Carolina
July 2, 2019

Piedmont Lithium I Technical Memorandum — Groundwater Model
Contents
Contents
Contents ............
ExecutiveSummary................................................................................................................... 1
Introduction................................................................................................................................
1
Conceptual Site Model/Groundwater Model Framework............................................................
1
ModelDomain........................................................................................................................
2
WaterBudget.........................................................................................................................
2
Hydrostratigraphy...................................................................................................................
2
BoundaryConditions..............................................................................................................
3
Recharge............................................................................................................................
4
Streams..............................................................................................................................
4
Rivers.................................................................................................................................
4
Wetlands.............................................................................................................................
5
Ponds.................................................................................................................................
5
Wells...................................................................................................................................
5
MinePits.............................................................................................................................
5
TemporalConstraints.............................................................................................................
5
Dewatering and Water Handling.............................................................................................
6
ModelSet-up.............................................................................................................................
6
ModelingSoftware..................................................................................................................
6
Discretization..........................................................................................................................
6
ModelLayers..........................................................................................................................
6
BoundaryConditions..............................................................................................................
7
Recharge............................................................................................................................
7
Streams..............................................................................................................................
7
Ponds.................................................................................................................................
7
River...................................................................................................................................
7
No-flow...............................................................................................................................
7
InitialCalibration.....................................................................................................................
8
Preliminary Dewatering Simulation.........................................................................................
9
ModelLimitations......................................................................................................................13
Summary and Conclusions.......................................................................................................13
References...............................................................................................................................15

Piedmont Lithium I Technical Memorandum — Groundwater Model ���
Contents
Figures
Figure 1 - Site Location Map
Figure 2 - Receptor Well Location Map
Figure 3 - Boundary Conditions
Figure 4 - Model Grid
Figure 5 - Distribution of Soft Rock and Hard Rock in Layers 4 and 5
Figure 6 - Distribution of Calibrated Heads
Figure 7 - Computed Heads versus Measured Heads
Figure 8 - Location of Stream Flow Measurements
Figure 9a - Model Predicted Drawdown from Dewatering in the Central Pit
Figure 9b - Model Predicted Drawdown from Dewatering in the East Pit
Figure 9c - Model Predicted Drawdown from Dewatering in the North Pit
Figure 9d - Model Predicted Drawdown from Dewatering in the South Pit
Figure 10 - HDR Delineated Wetlands
Figure 11 - Location of Stream Reaches
Tables
Table ES-1 — Model Predicted Dewatering Rate by Pit
Table 1- Observed and Predicted Water Levels......................................................................... 8
Table 2 - Simulated Base Flow and Base Flow Reported by Daniel, Smith, and Eimers (1997). 9
Table 3 - Simulated Base Flow and Stream Flow Measured on May 13 and 15, 2019 ............... 9
Table 4 - Model Predicted Dewatering Withdrawal Rates by Pit................................................10
Table 5 - Model -predicted Drawdown in Local Wells.................................................................11
Table 6 - Model -predicted Changes in Groundwater Flow to Wetlands (in gpm) .......................12
Table 7 - Changes in Base Flow to Streams that Cross the Site...............................................12

Piedmont Lithium I Technical Memorandum — Groundwater Model ���
Contents
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Piedmont Lithium I Technical Memorandum — Groundwater Model ���
Executive Summary
Executive Summary
Piedmont Lithium Inc. (PLI) is proposing to construct an open pit mine in the Carolina Tin-
Spodumene Belt (TSB) of North Carolina where lithium -bearing pegmatites have been
identified. The mine site (the Site) is located in the TSB of the Piedmont physiographic province
in south-central North Carolina. The approximately 963-acre Site is located in unincorporated
Gaston County, on private land surrounding Hephzibah Church Road, east of Whitesides Road,
and west of Aderholdt Road, approximately 2.7 miles east of Cherryville, North Carolina.
The mining will be accomplished through open pit excavations that will require dewatering. As
part of the planning process, it is necessary to estimate the rate of water withdrawal during pit
dewatering and what effect, if any, it may have on local water resources and water users. On
behalf of PLI, HDR Engineering, Inc. of the Carolinas (HDR) has developed a three-dimensional
groundwater flow model to estimate dewatering rates and evaluate whether these rates have
the potential to increase or decrease groundwater supply in the surrounding area. This
preliminary groundwater model is based on our current understanding of the hydrogeologic
setting and planned pit excavation geometries, as of the date of this report. As additional data
are collected and mine pit geometry changes, the model may be refined to reflect these
changes.
Water resources within the Site include Beaverdam Creek, which flows in an easterly to
northeasterly direction through the Site and eventually drains to the South Fork Catawba River
off -site. Little Beaverdam Creek flows north through the Site to a confluence with Beaverdam
Creek. Additionally, multiple streams and wetlands were identified within the Site and mapped
through field work conducted by HDR and verified by the United States Army Corps of
Engineers (USACE) under action SAW-2018-01129. Potable and irrigation water is provided to
residential homes and cultivated fields via individual water supply wells; large capacity municipal
wells are not known to exist in the area. The Site location and surrounding area are shown on
Figure ES-1.
HDR used data from site -specific resource and hydrogeologic investigations; design -level mine
plans; local United States Geologic Survey (USGS) gauging stations; and published regional
geologic and hydrogeologic data to develop a six -layered groundwater flow model. Simulations
were conducted to assess the amount of withdrawal necessary to dewater the mine pits and to
assess potential impacts of pit dewatering on local water resources (wells, wetlands and
streams). The modeling was conducted in multiple scenarios where dewatering of the pits
(North, Central, South and East Pits) was simulated individually.
Model -predicted dewatering rates range from 375 gallons per minute (gpm) for the South Pit to
850 gpm for the Central Pit (Table ES-1).

Piedmont Lithium I Technical Memorandum — Groundwater Model ���
Executive Summary
Table ES-1: Model -Predicted Dewatering Rate by Pit
Pits
Dewatering Rate
WPM)
North
400
Central
850
South
375
East
600
Modeling demonstrated that shallow wells in the vicinity of the Site may experience water
column loss during pit dewatering. Predicted drawdown in wells within the Site boundary ranged
from 0 feet to 137 feet with an average of approximately 11 feet. Predicted drawdown in wells
beyond the Site boundary ranged from 0 feet to 39.5 feet with an average of 6 feet. PLI will
acquire through fee simple or long term lease all of the wells within the project boundary; and
therefore, loss of water column in these wells is informational purposes only, not material.
Beyond the Site boundary, two wells were projected to experience significant loss of water
column during dewatering of the East and Central Pits, while one (shallow supply) well was
predicted to go dry during dewatering of the North Pit.
To monitor water level fluctuations as a result of dewatering activities, PLI will install sentinel
monitoring wells along portions of the Site boundary. This monitoring is intended to allow for
early detection of potential drawdown effects to off -site supply wells. PLI will offer residents in
the immediate vicinity of the Site (within 1,500 ft.) to participate in a well inventory program and
will address impacts on a case by case basis. Wells that are affected through loss of water
column such that they cannot be used for residential water will be remedied by PLI, likely via
replacement of an existing shallow well with deeper wells, if required. PLI will acquire in fee
simple the property at 210 Hastings Road and the property at 633 Aderholdt Road as part of the
mine development.
Predicted impacts to wetlands were primarily observed during simulated dewatering of the East
and Central Pits with six and seven wetlands going dry, respectively. The South and North Pits
each have a single wetland that is predicted to go dry during dewatering. Base flow to three
streams crossing the site decreases between 0.01 and 10 percent, depending on the proximity
of the stream to the pit being dewatered, with the greatest decrease being in Little Beaverdam
Creek when the Central Pit is dewatered. Note that PLI currently plans to return water
withdrawn for dewatering to the streams at the downstream end of the Site via appropriate
NPDES permitted discharge points to reduce potential pumping effects during mine operation.
It is also possible that some water withdrawn for dewatering can be diverted to the wetlands
most effected by drawdown.
A more detailed summary of groundwater model construction, simulation, and results is
provided herein.

Piedmont Lithium I Technical Memorandum — Groundwater Model 01
Executive Summary
'figure ES-1 — Overview of PLI Site
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Piedmont Lithium I Technical Memorandum — Groundwater Model ���
Introduction
Introduction
Piedmont Lithium Inc. (PLI) is proposing to construct an open pit mine in the Carolina Tin-
Spodumene Belt (TSB) of North Carolina where lithium -bearing pegmatites have been
identified. The mine site (the Site) is located in the TSB of the Piedmont physiographic province
in south-central North Carolina. The approximately 963-acre Site is located in unincorporated
Gaston County, on private land surrounding Hephzibah Church Road, east of Whitesides Road,
and west of Aderholdt Road, approximately 2.7 miles east of Cherryville, North Carolina.
The mining will be accomplished through open pit excavations that will require dewatering. As
part of the planning process it is necessary to estimate the rate of water withdrawal during pit
dewatering and what effect, if any, it may have on local water resources and water users. On
behalf of PLI, HDR Engineering, Inc. of the Carolinas (HDR) has developed a three-dimensional
groundwater flow model to estimate dewatering rates and potential effects. This preliminary
groundwater model is based on our current understanding of the hydrogeologic setting and
planned pit excavation geometries, as of the date of this report. As additional data are collected
and mine pit geometry changes, the model may be refined to reflect these changes.
Conceptual Site Model/Groundwater Model
Framework
HDR constructed a six -layer groundwater flow model utilizing data from site -specific resource
and hydrogeologic investigations; design -level mine plans; local United States Geologic Survey
(USGS) gauging stations; and published regional geologic and hydrogeologic data. Data
sources included the following:
• Investigations conducted by HDR to evaluate the occurrence of groundwater,
including long-term water level monitoring, stream flow measurements, and an
aquifer test;
• Investigations conducted by HDR to identify and map the locations of on -site
streams, wetlands, and ponds;
• Drilling programs conducted for PLI to investigate the locations of minable lithium -
bearing pegmatites, which include descriptions of fractures and geology in the
subsurface;
• PLI's most recent estimate of pit shell extents;
• USGS stream gauging stations at Long Creek near Bessemer City, South Fork
Catawba River at Lowell, and Duharts Creek at SR 2439 near Cramerton;
• Stream flow measurements collected by HDR in May 2019 and stream flow data for
Indian Creek (portion within the model domain) presented in Daniel, Smith, and
Eimers (1997);
• Recharge as reported in Daniel, Smith, and Eimers (1997);
• Regional hydrostratigraphy from Schaeffer (2019) and Daniel, Smith, and Eimers
(1997) as the basis for hydrostratigraphy at the site;

Piedmont Lithium I Technical Memorandum — Groundwater Model ���
Conceptual Site Model/Groundwater Model Framework
• Locations and construction details (as available) for water supply wells within and
outside of the PLI permit boundary (see Figure 2);
• USGS Digital Elevation Model for ground surface elevations and extrapolation to
upper stratigraphy (overburden, saprolite, transition zone);
• USGS EROS Data Center - aerial photographs and ortho-images; and,
• Description of local geology (Kessler et. al, 1942).
Model Domain
The model domain is the simulated area that can potentially contribute water to the mine pit
during dewatering or that will be affected by dewatering. The model domain includes the
southern portion of the Indian Creek watershed (south of Indian Creek) to the north of the Site,
the Beaverdam Creek watershed (the site is wholly in Beaverdam Creek watershed), as well as
a reach of the South Fork Catawba River located between Indian Creek and Beaverdam Creek.
Most of the model domain is rural area; however, the southwestern most portion of the
Beaverdam Creek watershed does intersect a portion of the Town of Cherryville. Cherryville's
water distribution system sources its water outside of the model domain. The Site boundary and
model domain are shown on Figure 1.
Water Budget
The model domain is approximately 32.5 square miles and average annual recharge is
estimated to be about 10 inches per year, based on the USGS study done in the Indian Creek
Watershed (Daniel, Smith, and Eimers, 1997). The recharge in the model domain equates to
approximately 5.5 billion gallons of water added to the groundwater each year. No large water
withdrawals (e.g., municipal and industrial) were identified in the model domain, so the natural
state is that the groundwater recharge will eventually discharge to local streams, wetlands, and
the South Fork Catawba River. Some withdrawals are made from individual residential wells or
irrigation; however, those withdrawals are likely small compared to the recharge and are largely
returned to the ground through septic or sprinkler systems, so as not to significantly affect the
overall water budget.
Hydrostratigraphy
The Site is located within the TSB, which is comprised of metamorphic and igneous rocks
overlain by weathered byproducts of the rock and residuum (Kessler 1942, Schaeffer 2019).
These materials can be divided into the following hydrostratigraphy:
1. Overburden is generally residuum consisting of alluvial and regolith deposits. The
residuum is generally composed of clays from weathered bedrock, with some rock
fragments as gravel and sand.
2. Saprolite, which underlies the overburden, is soil that is derived from weathering of
bedrock in -situ where some of the original textures and structure of the bedrock are still
identifiable; however, the minerals have been altered by weathering to a consistency of
soil.

Piedmont Lithium I Technical Memorandum — Groundwater Model ���
Conceptual Site Model/Groundwater Model Framework
3. Transition Zone is a thin zone between the saprolite and the underlying bedrock where
there is less weathering, but the rock is still highly fractured, weathered, and not
competent.
4. Bedrock at the Site is generally metavolcanic amphibolite intruded by pegmatites (some
of which are spodumene bearing). The amphibolite exhibits little foliation or other
structures. Other portions of the Site and area within the model domain are comprised of
metasedimentary rocks which are foliated and, at some places, have relict bedding
present. Neither the metavolcanics nor the metasedimentary rocks have significant
primary porosity, so almost all of the water in these units exists in joints and fractures. At
some locations, Triassic diabase dikes have intruded the crystalline bedrock. These
intrusive volcanic rocks have not been metamorphosed and may be responsible for
some of the lineations described below. As reported by Daniel, Smith, and Eimers
(1997), groundwater flow in the bedrock aquifers is controlled by fracturing and further, it
is likely that erosion results along fractures so that streams and rivers are associated
with areas of higher fracturing and hence more transmissive fractured bedrock.
5. Lineations are visible in aerial photographs and topographic maps as stream valleys and
linear topographic expressions across the region. These lineations are likely due to
weakness in the underlying bedrock such as faults and fractures, as well as more easily
eroded rock units that were folded by tectonics. Because the lineations often represent
partings in the rock (faults, joints, and bedding planes), they can also indicate where
higher hydraulic conductivity zones exist. These lineations are mapable, based on
topography, and can be simulated as higher -hydraulic conductivity material in the
groundwater model; however, their attitude in the subsurface is not easily discerned, so
the precise location of these features in the subsurface is not truly known. Daniel, Smith,
and Eimers (1997) studied the difference in hydraulic conductivity associated with valley
floors, valley walls, and hill tops. They found that valley floors had higher hydraulic
conductivity than hill tops and that the valley walls are transitional between the two
extremes. This variation in hydraulic conductivity is consistent with the idea that valleys
are coincident with fracturing in the subsurface.
6. Mine Pits are dry voids in the model domain and will be simulated in the model as no -
flow cells (dry cells). Water may seep into the pits through the face wall; as described
below, this seepage will be accounted for using drain package boundary conditions set
to the bottom of each layer at the edge of the mine pit.
Boundary Conditions
Several factors affect the amount of water that enters and exits a groundwater flow system.
Since these factors occur at the input and output of water into the system, they are termed
"boundary conditions." The sum of the boundary conditions equates to the water budget of the
system (inflows need to equal outflows) and should equal zero, accounting for changes in
storage in the system. Inflow is generally through recharge, although under stress, water may
be diverted from adjacent systems or captured from surface water. Storage is from water
occupying space in the system and from compressibility of the aquifer matrix. Outflow under
natural conditions is usually to surface water bodies (streams, wetlands, rivers, lakes, and
oceans). At the Site, outflow (also termed discharge) is to streams (e.g., Beaverdam Creek),
wetlands (which typically feed streams), and rivers (e.g., the South Fork Catawba River). Close
to surface water bodies, where groundwater is near the ground surface, plants can use the
water and divert it from discharging to surface water through transpiration. Also, water will be

Piedmont Lithium I Technical Memorandum — Groundwater Model ���
Conceptual Site Model/Groundwater Model Framework
withdrawn from the system through water supply wells, reducing discharge to surface water.
These boundary conditions need to be accounted for in a groundwater model to assure the
appropriate water budget is simulated. The boundary conditions considered in the model are
shown on Figure 3.
Recharge
Recharge occurs when a portion of precipitation that falls in an area percolates into the
subsurface and arrives at the water table. Most precipitation is lost to evapotranspiration or runs
off to surface water; the remaining portion that infiltrates into the subsurface will eventually
recharge the groundwater. Daniel, Smith, and Eimers (1997) conducted a highly -detailed study
to estimate groundwater recharge in the Indian Creek watershed, which is the next watershed
north of the Site and partially within the model domain. This study included multiple stream flow
measurements on small branches of Indian Creek within the watershed. Ultimately the study
concluded that there were about 10 inches of recharge per year. Because the geology and
climate of Indian Creek are similar to (and connected with) the Beaverdam Creek watershed
where the PLI mining will take place, a recharge value of 10 inches per year is well supported
for the model domain.
Streams
Streams in the Eastern United States are generally gaining streams, meaning the stream is at
an elevation that intersects groundwater so groundwater discharges to the stream. The portion
of the stream flow that is supported by groundwater is termed "base flow"; streams also receive
flow from overland flow, which can make up most of the stream flow during large portions of the
year. The discharge to the stream (base flow) is controlled by the head in the aquifer adjacent to
the stream, as compared to the stage of the stream and the make-up of any sediment that lines
the bottom of the stream which will limit discharge proportional to the material's water
conductance. The geometry of the stream (i.e., width and length) also impacts how much water
can discharge to it. Conversely, if the stream's stage is higher than adjacent groundwater head,
then the stream can lose water to the groundwater, again limited by the stream's bottom
conductance. However, the amount of water that can be lost is also constrained by how much
water flows into the losing reach from any upstream gaining reaches (the stream cannot lose
more water than is in it). Again, the geometry of the stream will affect the amount of water that
can be lost. Streams are the most common boundary condition type in the model, so they
account for most of the groundwater discharge. Streams are usually simulated as head and
conductance limited fluxes that also account for upstream discharge.
Rivers
The down -gradient boundary of the model domain is the South Fork Catawba River. Similar to
streams, rivers can gain and lose water based on the relationship to the adjacent groundwater,
the conductance of the bottom sediments, and the geometry of the river itself. However, for the
most part, stresses simulated in the model domain are not sufficient to significantly change the
river flow, so rivers in effect have an unlimited supply of water and are not constrained by
upstream reaches in the same way as streams. Rivers are usually simulated as head and
conductance value limited fluxes with a specified river stage (river package).

Piedmont Lithium I Technical Memorandum — Groundwater Model ���
Conceptual Site Model/Groundwater Model Framework
Wetlands
Wetlands fall into two categories: those that receive groundwater and those that are isolated
from groundwater. In general, wetlands that receive groundwater will discharge into adjacent
streams. If the water table falls below the wetland and there is not an upstream source of water,
the wetland will go dry. The amount of water that will discharge to a wetland from groundwater
is controlled by the conductance of sediments in the wetland. Wetlands are typically simulated
as conductance -limited drains where water can be removed but no water is returned if
groundwater levels fall below the elevation of the drain.
Ponds
Ponds are similar to wetlands in that they can either receive water from groundwater or they are
isolated from the groundwater. However, ponds may also receive water from upstream and can
have their water level controlled by dams, so are part of the stream system. The ponds only
affect groundwater locally.
Wells
Wells are usually simulated as a specified flux from a specific interval within the groundwater.
Most of the wells within the model domain are low -yield domestic supply wells that do not
significantly affect groundwater flow within the model. For this evaluation, HDR added the
location and construction details of publically-documented domestic supply wells near the Site
such that effects of pit dewatering on these wells can be evaluated within the model. Note that
pumping rates for these wells were not publically available, thus, pumping in the domestic
supply wells is not simulated in the model.
Mine Pits
As described above, the mine pits are represented as voids within the model domain. These
voids are either air -filled or water -filled, depending on stage of mining. If they are air -filled, then
water in the adjacent formation will be removed by either dewatering or evaporation at the pit
face. Water is not returned to the groundwater from the air -filled pit; however, it may be
discharged to an adjacent wetland or stream where it could infiltrate groundwater if the stream —
groundwater head relationship creates a losing stream. Water -filled pits act like surface water
bodies and can be simulated as very high -hydraulic conductivity material.
Temporal Constraints
The preliminary model was run as a steady-state model, which assumes the mine pits have
individually been fully excavated. In this case, the greatest amount of drawdown occurs during
dewatering at the designed terminal depth of excavation (full excavation). Note that once mining
reaches full excavation for a given pit, the pit will fill with water and potentially be filled by
excavated material from an adjacent pit. Steady-state simulations estimate mean conditions
without accounting for temporal variation. Because the pits will be dewatered in sequence and
only portions of different pits open at the same time, four predictive simulations were done, one
for each individual mine pit being dewatered separately. Transient simulations that account for
mine pit sequencing may be undertaken in the future, if that level of detail is necessary.

Piedmont Lithium I Technical Memorandum — Groundwater Model ���
Model Set-up
Dewatering and Water Handling
Water in the preliminary model is assumed to be pumped from the lowest level of the mine pit
and discharged to the adjacent streams. This assumption means that the dewatering can be
simulated with a drain, so the model will estimate the amount of water removal needed to
achieve the dewatering; the model does not account for the water after it has been removed
(removed water does not recharge groundwater elsewhere in the model). Future modeling can
simulate the effects of re -introducing dewatering water to the groundwater or elsewhere in the
model and can be used to estimate aquifer recovery time after dewatering has ceased, if such
simulations are needed.
Model Set-up
Modeling Software
Groundwater modeling was performed using the USGS groundwater model software,
MODFLOW-NWT (Niswonger, 2011). MODFLOW variable grid spacing allows the user to
create model grids that focus on areas of interest, while using generalized information for
remote areas. Aquaveo's model pre- and post -processing software, GMS, was used to develop
the groundwater flow model. GMS's graphic interface and data handling functions allow the
creation of a base conceptual site model (CSM) to create the hydrogeologic framework that is
the basis for the groundwater flow model. Once the model is set up, GMS also enables the user
to display model output and compare the output to observed data (calibration targets).
Discretization
The model grid was refined both horizontally and vertically so that features of the CSM and the
focus area near the Site could be simulated with greater detail than remote areas which are
generalized. Cells in the model range between 50 feet on a side where the grid is focused and
500 where it is generalized further away from the Site. The model grid is shown on Figure 4.
Model Layers
The model was constructed using the following six layers to represent hydrostrigraphy within the
model domain.
• Layer 1 — Overburden — regolith and fluvial deposits, calibrated hydraulic conductivity
of 1.5 feet per day and vertical anisotropy of 2.0.
• Layer 2 — Saprolite — bedrock eroded to soil, calibrated hydraulic conductivity of 1.0
feet per day and vertical anisotropy of 2.0.
• Layer 3 - Transition Zone — highly fractured and weathered rock beneath the
saprolite, calibrated hydraulic conductivity of 2.0 feet per day and vertical anisotropy
of 2.0.

Piedmont Lithium I Technical Memorandum — Groundwater Model ���
Model Set-up
Layers 4 and 5 — Bedrock — as discussed above, bedrock near streams (topographic
lows) is more transmissive than at hill tops (Daniel, Smith, and Eimers, 1997). For
this reason, two bedrock types were simulated: soft rock near streams and hard rock
between streams. Soft rock was assigned a calibrated hydraulic conductivity of 0.25
feet per day and vertical anisotropy of 1.0. Hard rock was assigned a calibrated
hydraulic conductivity of 0.0075 feet per day and vertical anisotropy of 1.0. The
distribution of soft rock and hard rock in Layers 4 and 5 is shown on Figure 5.
• Layer 6 — Deep bedrock — entirely hard rock, assuming that the fractures are closed
due to the compressing weight of overlying rock, calibrated hydraulic conductivity of
0.0075 feet per day and vertical anisotropy of 1.0.
Boundary Conditions
Recharge
Recharge is based on studies done in the Indian Creek watershed by Daniel, Smith, and Eimers
(1997), who determined that recharge in the area covered by the model domain to be 10 inches
per year. This recharge value is applied to the highest active cell. Recharge was simulated
using constant flux in the MODFLOW Recharge package.
Streams
The streams placed into the model are based off the USGS NHD flow lines shapefile (USGS
2019) for generalized areas of the model and digitized stream map shapefile (HDR, 2018) at the
Site. They were placed in the model using the stream package, which allows for different
reaches and segments of the stream to gain or lose water. Each node along the streams was
referenced to the surface elevation in the grid and assigned an elevation. This elevation was
used to put the streams into the model at the correct elevations. For the stream package, the
river conductance, roughness, width, and incoming flow (connection with upstream stream
segments) was added to each segment of the stream. Beaverdam Creek is the largest stream
within the domain and was input with a channel width of 25 ft. Little Beaverdam Creek is the
second largest stream within the model domain and was input with a width of 15 ft. The smaller
tributary streams were assigned a width of 5 ft.
Ponds
In general, ponds in the model domain are created by small dams on streams and creeks.
Although they will effect groundwater flow locally, they do not significantly affect the system
beyond the effects of a stream at the same location. For that reason, changes in simulated base
flow in streams is used to gauge impacts on ponds.
River
The down -gradient boundary of the model domain is the South Fork Catawba River. This
portion of the domain boundary was applied using the River package in MODFLOW. This
package uses the riverbed elevation and conductance values along the stretch of the river.
No -flow
No -flow cells are inactive model grid cells through which water cannot pass (except recharge
may be applied to an underlying cell if the upper cells are no -flow or dry and underlying cells are

Piedmont Lithium I Technical Memorandum - Groundwater Model ���
Model Set-up
not). The domain is bounded by no -flow cells, which define the model domain. Also, no -flow
cells are used to simulate the empty space of pits.
Initial Calibration
Once constructed, the groundwater model results were compared to mean water levels from 10
monitoring wells at the Site, base flow estimates for streams in the Indian Creek watershed as
documented by Daniel, Smith, and Eimers (1997), and stream flows measured in May 2019
within the Site boundary.
Groundwater levels measured in 10 monitoring wells were evaluated to find the mean water
level and range of variability. Water levels simulated by the base model were compared to these
measured mean water levels. Simulated water levels in 9 of 10 wells were within the range of
observed levels and approached the mean levels. The simulated water level in the nine wells
was within two standard deviations of the mean water level and within one standard deviation of
the mean in four wells. The Root Mean Squared error for the base simulation is 3.60 feet, while
the mean square of the observed standard deviation is 4.32 feet. Water levels in MW-1 were
predicted to be nearly 30 feet higher in elevation than measured water levels in the well (note
that although MW-1 is on a hillside, it has the lowest water level of any monitoring well at the
Site). This could be due to local a feature not simulated by the model, such as a nearby large
fracture or spring. Adjusting the model so that the water levels in MW-1 would reflect the
measured water levels would require loss of calibration at all other wells. The distribution of
calibrated heads at the Site is shown on Figure 6. The computed heads, as compared to
measured heads, are shown on Figure 7. Simulated heads and measured head statistics are
presented in Table 1.
Table 1- Observed and Predicted Water Levels
Well
Top of
Screen
Elevation
(feet)
Bottom of
Screen
Elevation
(feet)
Mean
Observed
Head
(feet)
One
Standard
Deviation
(feet)
Predicted Difference in Observed
Head vs. Predicted Head
(feet) (feet)
MW-1
702.49
652.49
743.65
1.56
771.72
-28.07
4.55
MW-4
782.97
731.97
847.48
2.95
842.93
MW-2
764.12
714.12
817.57
1.46
816.17
790.31
753.73
1.40
-3.24
-1.89
MW-3
725.39
673.39
787.07
2.40
OW-1 S
721.63
701.63
751.84
2.39
OW-1 D
636.14
418.14
752.20
2.34
752.83
-0.63
0W-2S
750.87
730.87
747.36
1.85
750.66
-3.30
PW-1
631.75
236.75
750.18
2.33
751.44
-1.26
OW-21D
630.05
439.05
747.81
1.91
751.17
-3.36
MW-5
696.75
642.75
745.38
1.63
747.99
-2.61
Total flow is defined as a stream's direct response to a rainfall event and includes runoff into the
streams, lateral flow from the soil, and base flow. Base flow is the portion of stream flow which
is discharged from the aquifer. Base flows were determined by Daniel, Smith, and Eimers
(1997) at four locations on Indian Creek within the model domain. The base flow simulated by

Piedmont Lithium I Technical Memorandum - Groundwater Model
Model Set-up
the base model was compared to these locations. The comparison of simulated stream flows to
base flows determined by Daniel, Smith, and Eimers (1997) are presented in Table 2. Stream
flow (specifically base flow) measurement locations that were compared to the calibrated model
are shown on Figure 8.
Table 2 - Simulated Base Flow and Base Flow Reported by Daniel, Smith, and Eimers (1997)
Stream
Reported Flow (1997)
Modeled Flow
Percent
Number
(ft3/s)
(fts/s)
Difference
81
0.16
0.17
5.6
79
0.75
0.69
7.3
82
1.79
1.77
1.4
75
0.28
0.26
6.5
Stream flows within the Site were measured on May 13 and 15, 2019. The USGS stream gage
on Indian Creek (the adjacent watershed) was at the 95th percentile and 851h percentile daily
flows for those two days, meaning elevated total flow was measured and not base flow. When
these stream flows are compared to model output (base flow, so likely less than 50th percentile),
all flows were less than measured and most at about 50 percent of observed. While this is a
qualitative comparison, the model -predicted base flows are within observed flows and likely
approaching actual base flow values. The measured stream flows and model -predicted base
flow are summarized in Table 3. Additional stream flows will be measured over time and the
comparison to model predicted base flow can be refined when additional lower flow data is
collected.
Table 3 - Simulated Base Flow and Stream Flow Measured on May 13 and 15, 2019
Stream
Number
Measured Stream
Flow
5/13 - 15/19
Modeled Base
Flow Percent
Difference
(ft3/s)
(ft3/s)
FM1
24.1
12.12
49.73
FM6
9.1
6.42
29.43
FM3
8
5.24
34.53
FM4
12.2
6.33
48.10
FM2
20.9
6.38
69.49
Weir 5
0.22
0.03
84.20
Weir 6
0.83
0.23
72.67
Weir 2
0.60
0.15
75.47
Weir 4
0.42
0.06
86.41
Preliminary Dewatering Simulation
Once the base model -predicted heads and stream flows reasonably reproduced measured
heads and stream flows as described above, the model was considered calibrated and was
used to simulate dewatering of the mine pits. Mine pit dewatering was accomplished by

Piedmont Lithium I Technical Memorandum — Groundwater Model ���
Model Set-up
changing model cells within the footprint of the mine to no -flow cells in layers 1 through 5 and
then simulating a drain at the base of each layer in the first active cell outside the no -flow cells.
Water in the layer adjacent to the pit is removed by the drain in the same way it would seep
through the face of the pit, or flows into a lower layer and is removed by the drain in that layer.
The water removed by all drains simulating dewatering was summed to estimate the dewatering
volumes needed to dewater the pit and drawdown of the water table was calculated as a result
of this withdrawal. Each pit was simulated separately and as steady-state at the time when the
pit is its largest.
The estimated withdrawal rates for each pit based on these simulations are:
Table 4 - Model Predicted Dewatering Withdrawal Rates by Pit
Pits
Pump Rate (gpm)
North
400
Central
850
South
375
East
600
Based on these dewatering withdrawal rates, predicted drawdown in wells within the Site
boundary ranges from 0 feet to 137 feet with an average of approximately 11 feet. Predicted
drawdown in wells beyond the Site boundary ranges from 0 feet to 39.5 feet with an average of
6 feet. Within the Site boundary, one well is predicted to experience significant loss of water
column (loss of available drawdown) during dewatering of the Central Pit. Beyond the Site
boundary, two wells are projected to experience significant loss of water column during
dewatering of the East and Central Pits, while one (shallow supply) well is predicted to go dry
during dewatering of the North Pit. Estimated drawdown in wells within and beyond the Site
boundary are presented in Table 5 and shown on Figures 9a, b, c, and d. The drawdown
depicted in the figures range from 0.5 ft to 400 ft of drawdown. The receptor wells and wetlands
are represented with green circles and light blue, respectively.
To monitor water level fluctuations as a result of dewatering activities, PLI will install sentinel
monitoring wells along portions of the Site boundary. This monitoring is intended to allow for
early detection of potential drawdown effects to off -site supply wells. PLI will offer residents in
the immediate vicinity of the Site (within 1,500 ft.) to participate in a well inventory program and
will address impacts on a case by case basis. Potential affects to local wells will be remedied by
PLI, likely via replacement of existing shallow wells with deeper wells less likely to be affected
by mine operations or through acquisition'. PLI will acquire in fee simple the property at 210
Hastings Road and the property at 633 Aderholdt Road as part of the mine development.
' PLI will acquire through fee simple or long term lease all of the wells within the project boundary; and
therefore any loss of water column in these wells is informational purposes only, not material.
10

Piedmont Lithium I Technical Memorandum - Groundwater Model ���
Model Set-up
Table 5 - Model -predicted Drawdown in Local Wells
Well Address
Well Depth
(ft)
Reported
Depth to
Water (ft)
Drawdown during Dewaterin
Available Water Column during Dewaterin
South
Pit
East
I Pit
Central
Pit
North
Pit
No
Dewatering
South
Pit
East
Pit
Central
Pit
North
Pit
Wells within the Site Boundary
1523 R W McLamb Dr.
185
15
17.0
0.7
55.5
0.1
170
153.0
169.3
114.5
169.9
819 Whitesides Rd.
180
34
0.8
0.1
17.4
0.1
146
145.2
145.9
128.6
145.9
1121 Hephzibah Church Rd.
300
40
2.5
0.6
41.4
8.6
260
257.5
259.4
218.6
251.4
901 Whitesides Rd.
56
24
0.6
0.1
5.4
0.7
32
31.4
31.9
26.7
31.3
921 Whitesides Rd
150
30
1.2
0.2
12.0
1.3
120
118.8
119.8
108.0
118.7
1266 Hephzibah Church Rd.
300
1 40
29.8
137.1
23.9
0.8
1 260
230.2
123.0
236.1
259.3
1021 Hephzibah Church Rd.
45
35
0.3
0.1
3.2
1.5
10
9.7
9.9
6.8
8.6
1029 Hephzibah Church Rd.
0.8
0.2
15.4
7.9
Wells beyond the Site Boundary
732 Whitesides Rd.
166
20
6.0
0.5
15.8
0.0
146
140.0
145.5
130.2
146.0
129 George Pa seur Rd.
63
33
3.0
1.3
1.7
0.0
30
27.0
28.8
28.3
30.0
210 Hastings RV
50
25
0.3
20.0
0.2
0.0
25
24.7
5.0
24.8
25.0
663 Aderholdt RV
62
40
0.0
0.9
11.4
39.5
22
22.0
21.1
10.6
-17.5
633 Aderholdt RV
0.1
7.0
12.4
17.9
534 Whitesides Rd.
550/690
40
0.4
0.3
0.2
0.0
510
509.6
509.7
509.8
510.0
Note: Yellow -shaded cells indicate potentially significant loss of storage in a well, as simulated by the model, during dewatering of an individual mine pit; red -shaded cells indicate
potentially dry well during dewatering.
PLI will acquire through fee simple or long term lease all of the wells within the project boundary; and therefore any loss of water column in these wells is informational only, not
material and will also acquire in fee simple and property at 210 Hastings Road and the property at 633 Aderholdt Road as part of the mine development.
11

Piedmont Lithium I Technical Memorandum - Groundwater Model ���
Model Set-up
Changes in groundwater flow to wetlands were estimated by comparing flow to wetlands in the
base simulation with flow to wetlands in each pit dewatering scenario. Wetlands are most
impacted by dewatering the East and Central Pits with six and seven wetlands going dry,
respectively. Simulated dewatering of the South and North Pits each result in drying of a single
wetland. Changes in groundwater discharge predicted by the model for each pit dewatering
scenario are presented on Table 6. Wetland locations, as referenced in Table 6, are shown on
Figure 10.
Table 6 - Model -predicted Changes in Groundwater Flow to Wetlands (in gpm)
Wetland
Wetland Size
(Acres)
Calibrated Model
East Pit
South Pit
Central Pit
North Pit
Flow
Flow
% Difference
Flow
% Difference
Flow
% Difference
Flow
% Difference
Wetland 1
0.28
22.03
9.74
55.79
19.15
13.06
DRY
DRY
3.47
84.25
Wetland 2
0.15
44.94
DRY
DRY
44.71
0.52
43.67
2.83
44.64
0.67
Wetland 3
3.19
61.24
DRY
DRY
60.31
1.51
17.96
70.67
32.72
46.57
Wetland 4
0.66
9.71
DRY
DRY
5.89
39.33
DRY
DRY
2.11
78.22
Wetland 5
2.21
1 45.21
DRY
DRY
12.17
73.09
11.11
75.43
42.74
5.46
Wetland 6
0.09
24.86
DRY
DRY
7.38
1 70.32
19.95
19.73
24.78
0.31
Wetland 7
0.38
34.60
1.62
95.32
21.09
39.06
32.07
7.33
34.58
0.06
Wetland 8
0.23
27.21
DRY
DRY
DRY
DRY
15.69
42.33
27.10
0.42
Wetland 9
0.18
14.82
14.74
0.92
14.45
4.66
11.63
39.74
13.85
12.51
Wetland 10
0.12
24.05
24.02
0.13
23.89
0.65
22.69
5.66
23.73
1.32
Wetland 11
0.04
24.89
24.45
1.77
12.03
51.66
DRY
DRY
24.62
1.06
Wetland 12
0.06
25.14
1 24.86
1.14
19.59
22.09
DRY
DRY
24.90
0.97
Wetland 13
0.09
35.84
35.66
0.52
33.34
1 7.00
DRY
DRY
35.54
0.86
Wetland 14
5.45
55.99
55.78
0.38
54.37
2.89
38.26
31.66
55.14
1.52
Wetland 15
0.04
33.95
33.93
0.08
33.85
0.29
32.64::E
3.86
32.20
5.17
Wetland 16
1 0.08
25.63
25.43
0.77
25.22
1.58
6.95
1 72.90
DRY
DRY
Notes:
1. Orange -shaded cells indicate where wetlands are predicted to go dry.
2. Red text indicates where groundwater flow has been reduced to a wetland by more than 50 percent.
Changes in stream base flow, or the groundwater contribution to overall stream flow, was also
assessed using the model. Base flow simulated during pit dewatering for each pit scenario was
compared to base flows predicted in the base model in three streams that cross the Site.
Decreases in base flow to Beaverdam Creek ranged from 5.3 percent when the East Pit is
dewatered to 10.2 percent when the Central Pit is dewatered. Decreases in base flow to Little
Beaverdam Creek ranged from 0.01 percent when the Central Pit is dewatered to 3.5 percent
when the East Pit is dewatered. Decreases in base flow to an unnamed tributary to Beaverdam
Creek (Stream 3) ranged from 0.06 percent when the South Pit is dewatered to 6.9 percent
when the East Pit is dewatered. Model -predicted changes in base flow for the three streams that
cross the Site (summed at the downstream end of the site) are presented in Table 7. The
locations of the streams identified in Table 7, and the location where base flow was summed
with respect to the Site, are shown on Figure 11.
Table 7 - Changes in Base Flow to Streams that Cross the Site
Streams
Calibrated
East Pit,
% Dif.
South Pit,
% Dif.
Central Pit,
% Dif.
North Pit,
% Dif.
Ft3/d
Ft3/d
Ft3/d
Ft3/d
Ft3/d
Beaverdam Creek
-1073419
-1016923
5.3
-1012505
5.7
-963527
10.2
-1016584
5.3
(Stream 1)
Little Beaverdam
-452506
-436797
3.5
-441588
2.4
-448860
0.8
-452463
0.01
Creek (Stream 2)
Stream 3
-84288
-78453.00
6.9
-84235
0.06
-83485
0.95
-84088
0.24
12

Piedmont Lithium I Technical Memorandum — Groundwater Model ���
Model Limitations
Model Limitations
All models require generalization and many details of the groundwater flow system cannot be
reasonably simulated without extensive data gathering and detailed inputs. For the most part,
these details are captured in, or bounded by, the overall generalization, but they can have local
effects that could be consequential to specific outcomes in the real world. As an example,
anomalously low water levels in MW-1 cannot be explained by the current model and some field
work would likely be required to evaluate likely reasons for the anomaly. Other limitations of the
model that need to be considered are as follows:
• Subsurface conditions are varied and complex. The model simulates fractured bedrock,
a highly complex network of conduits that as a whole can act like a porous media, but on
smaller scales can become almost independent systems. For example, an unexpected
amount of water could be produced where a large undetected fracture intersects both a
stream and a newly excavated pit. The current model cannot predict such an outcome.
The water budget is based on a study done in the adjacent Indian Creek watershed. It is
possible that conditions either in the subsurface or climatologically could be different
between the two watersheds, resulting in differing amounts of water being available, thus
causing some uncertainty in the overall water balance. Note that the model does not
simulate evapotranspiration, which can significantly reduce stream flows during certain
times of the year.
• Sensitivity analyses have not been conducted, but could show that model predictions are
sensitive to one or more of the parameters used in the model. Note that model runs
conducted during set up and calibration showed that the model can be sensitive to
hydraulic conductivity, recharge, and stream conductance. Sensitivity analyses could be
conducted if necessary.
Summary and Conclusions
HDR has developed a preliminary groundwater flow model to estimate the rate of groundwater
withdrawal necessary to dewater four planned mine pits under steady-state conditions and
evaluate the potential effects of dewatering on local water resources. The six -layer model was
constructed using data from site -specific resource and hydrogeologic investigations; design -
level mine plans; local USGS gaging stations; and published regional geologic and
hydrogeologic data. The model was calibrated to heads measured in on -site monitoring wells,
stream flow readings measured in on -site streams and tributaries, and to published data from
local and regional sources.
Model -predicted dewatering rates ranged from 375 gpm for the South Pit to 850 gpm for the
Central Pit. Predicted drawdown in wells within the Site boundary ranged from 0 feet to 137 feet
with an average of approximately 11 feet. Predicted drawdown in wells beyond the Site
boundary ranged from 0 feet to 39.5 feet with an average of 6 feet. Within the Site boundary,
one well is predicted to experience significant loss of water column (loss of available drawdown)
during dewatering of the Central Pit. Beyond the Site boundary, two wells are projected to
experience significant loss of water column during dewatering of the East and Central Pits, while
one (shallow supply) well is predicted to go dry during dewatering of the North Pit.
13

Piedmont Lithium I Technical Memorandum — Groundwater Model ���
Summary and Conclusions
Potential affects to wells within the Site boundary will be mitigated via condemnation and
abandonment of supply wells as mine construction occurs. Potential affects to wells beyond the
Site boundary will be evaluated, at the request of NCDEQ, via installation and periodic
monitoring of groundwater piezometers at the Site boundary. Should pumping effects be
observed in one or more piezometers during dewatering, PLI will mitigate the drawdown effects
accordingly, possibly through abandonment and re -installation of wells on a case -by -case basis.
Predicted impacts to wetlands were primarily observed during simulated dewatering of the East
and Central Pits with six and seven wetlands going dry, respectively. The South and North Pits
each have a single wetland that is predicted to go dry during dewatering. Base flow, or the
contribution of groundwater to overall flow, to three streams crossing the site decreases
between 0.01 and 10 percent, depending on the proximity of the stream to the pit being
dewatered. The greatest decrease in base flow was predicted in Little Beaverdam Creek when
the Central Pit is dewatered. Note that PLI currently plans to return water withdrawn for
dewatering to the streams at the downstream end of the Site via appropriate NPDES permitted
discharge points to reduce potential pumping effects during mine operation. It is also possible
that some water withdrawn for dewatering can be diverted to the wetlands most effected by
drawdown.
14

Piedmont Lithium I Technical Memorandum — Groundwater Model ���
References
References
C.C. Daniel III, D. G. Smith, and J. L. Eimers, 1997, Hydrogeology and Simulation of Ground -
Water Flow in the Thick Regolith-Fractured Crystalline Rock Aquifer System of Indian Creek
Basin, North Carolina. USGS Water -Supply Paper 2341.
HDR, 2018, shapefile of streams and wetlands on the PLI site.
T. L. Kessler, 1942 The Tin-spodumene belt of the Carolinas, a preliminary Report; Strategic
Minerals Investigation, Part 2, J-R USGS Bulletin 936 pp. 245 — 269.
R.G. Niswonger, Panday, Sorab, and Ibaraki, Motomu, 2011, MODFLOW-NWT, A Newton
formulation for MODFLOW-2005: U.S. Geological Survey Techniques and Methods 6-A37, 44
P.
M. F. Schaeffer, 2019; Carolina Piedmont Groundwater System — Existence of the Transition
Zone Between Regolith and Bedrock; IAEG/AEG Annual Meeting Proceedings, San Francisco,
California, 2018 — Volume 2 Springer Nature Switzerland AG 2019.
T. Spruill; USGS Coastal Plain Ground -Water Recharge;
https:Hnc.water.usgs.gov/projects/coastal qw/index.html, 2003-2005.
U.S. Geological Survey, NHD for North Carolina State or Territory Shapefile Model Version
2.2.1: U.S. Geological Survey, 2019.
15

Piedmont Lithium I Technical Memorandum - Aquifer Test ���
Figures
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DATA SOURCES: State Plane Coordinate System,
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DATA SOURCES: State Plane Coordinate System,
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W n I10*
FIGURE 5
PATH: C:\USERSIJTROYERIDESKTOP\PROJECTS1o0/ PIEDMONT LITHIUM MINE\GIMFIGURE 5.MXD -USER: JTROYER -DATE: 6/24/22019

DRAFT
rxamoie ora wie,�auon W',,. ooservaam IaNei eimr oars
Sources: Esri, HERE, Garmin, Intermap, increment P Corp., GEBCO,
USGS, FAO, NPS, NRCAN, GeoBase, IGN, Kadaster NL, Ordnance
Survey, Esri Japan, METI, Esri China (Hong Kong), swisstopo,
OpenStreetMap contributors, and the GIS User Community
Sources: Esri, HERE, Garmin'
Intermap, increment P Corp.,
GEBCO, USGS, FAO, NPS,
NRCAN, GeoBase, IGN,
{-lead
1000.0
970.0
940.0
910.0
8w.0
850.0
820.0
790.0
760.0
730.0
700.0
DATA SOURCES: State Plane Coordinate System,
Zone: North Carolina (FIPS 3200), NAD 19832011, feet
CALIBRATED HEADS
DISTRIBUTION OF CALIBRATED HEADS
AT THE SITE
N
ead
0 1 2
MILES
PIEDMONT ��1
LIT HIWA
FIGURE 6
PATH:
PIEDMONT LITHIUM MINEIGIS\PIEDMONT LITHIUM MINE.MXD - USER: JTROYER - DATE: 6113/2019

Computed vs. Observed Heads
860
840
820
G1
3
cL 800
E
O
U
780
•
760
•
740 - -
720 740 760 780 800 820 840
Observed
860
4 MW-1
4 MW-4
• MW-2
0 MW-3
OW-1S
OW-1D
• OW-2S
• PW-1
OW-2D
M W-5
• • • • • • Trendline
PIEDMONT Computed Heads vs. Measured Heads Figure
L17H141M

z
e
$w.
crvuaa
F� scram Rd /J/!
79
Source : E ri, HERE, Garmin,
P Intermap, increment Corp.,
GEBCO, USGS, FAO, NPS,
—NRCAN, GeoBase, IGN,
LEGEND
Q Site
Q Model Domain
® Pits
Ti '4 0 Daniel, Smith, and Eimers
8
HDR Flow Measurements
ib
DATA SOURCES: State Plane Coordinate System,
Zone: North Carolina (FIPS 3200), NAD 1983 2011, feet
STREAM FLOW MEASUREMENTS
LOCATION OF HDR MEASUREMENTS
AND DANIEL, SMITH, AND EIMERS
MEASUREMENTS
N
0 1 2
MILES
� r B�d+rch
.� FN
Sources: Esri, HERE, iiGarmin, Intermap, increment F Corp., GEBCO, � �� E ❑���T
USGS, FAO, NIPS, NRCAN, GeoBase, IGN, Kadaster NIL, Ordnance q 1
zSurve , Esri Ja an, METI, Esri China Hon Kong), a �t�M�a FIGURE 8
y p (Hong g), swisstopo,
OpenStreetMap contributors, and the GIS User Communi[y
a NA
�X
Jr,eT,.
PATH: C:\USERSIJTROYERIDESKTOP\PROJECTSIOOI PIEDMONT LITHIUM MINE\GIS\FIGURE 8.MXD -USER: JTROYER -DATE: 6/24/2019

so
0
r
Sources: Esri, HERE, Garmin,
Intermap, increment P Corp.,
GEBCO, USGS, FAO, NIPS,
NRCAN, GeoBase, IGN,
LEGEND
® Receptor Wells 25
Drawdown (ft) 50
0.5 75
5 100
10 200
15 300
20 — - 400
DATA SOURCES: State Plane Coordinate System,
Zone: North Carolina (FIPS 3200), NAD 1983 2011, feet
MODEL PREDICTED DRAWDOWN
FROM DEWATERING IN THE
CENTERAL PIT
N
III II III III I IIIII III IIIIIIII III 0 0.5 1
MILES
Sour�c,�P Esri, HERE, Garmin, Inter ap, increment P Corp., GEBC I E D���1`l T FN
IIIISGS!IIFAO1, KIPS, �NR i AN�,���GeoBasle�� IGN,��Kadaster INI Ordn�anice
urwtuM
Survey, Esri Japan, METI, Esri China (Hong Kong), swisstopo,
Op"enStreetMap contributors, and the GIS User Community FIGURE 9a
PATH: C:\USERSIJTROYERIDESKTOP\PROJECTS\002 HASTINGSIGIS\CONTOURS FIGURE.MXD-USER: JTROYER - DATE: 612612019

t
]-®
Sources: Esri, HERE, Garmin,
Intermap, increment P Corp.,
GEBCO, USGS, FAO, NPS,
NRCAN, GeoBase, IGN,
LEGEND
® Receptor Wells 25
Drawdown (ft) 50
0.5 75
5 100
10 200
15 — 300
20 400
DATA SOURCES: State Plane Coordinate System,
Zone: North Carolina (FIPS 3200), NAD 1983 2011, feet
MODEL PREDICTED DRAWDOWN
FROM DEWATERING IN THE
PACT PIT
0 01 1
.5 1
MILES
Sourceso Esri, HERE, Garmin, Interma increment P i rp. E C h I E D���1`l T FN
w iil Ili Ilniln III II a III II IIII 111 '
USGS, FA II lPS,11NRIIAN, GeoBase,1IGN, F'�adaster�N 0If11Ordin, utRIUM
Survey, Esri Japan, METI, Esri China (Hong Kong), swisstopo,
__.J ♦L.. - I . ___.._.... FIGURE 9b
PATH:C:\USERSIJTROYERIDESKTOP\PROJECTS1002 HASTINGSIGIS\CONTOURS FIGURE.MXD-USER: JTROYER - DATE: 612612019

i110 0
.0.0 map, increment P Corp.,
�"II III
I'I III , II Receptor Wells 25
DATA SOURCES: State Plane Coordinate System,
Zone: North Carolina (FIPS 3200), NAD 1983 2011, feet
FROMOEwPIT
�aIxG IN2. MODEL PREDICTED —
l ,.,.,
Survey,E�_� ,.o�k�oFN
�o"" �kr
,IS NO IN :A11'V����"8[,0w�..o,�.�aEa.,gym:,,,:....,..u.m.M ,I5
PATH:C:\USERSIJTROYERIDESKTOP\PROJECTS1002 HASTINGSIGIS\CONTOURS FIGURE.MXD-USER: JTROYER - DATE: 612612019

0
v�
gei+�di+� C eat
1
�. Sources: Esri, HERE, Garmin,
4`ea� Intermap, increment P Corp.,
GEBCO, USGS, FAO, NPS,
�e NRCAN, GeoBase, IGN,
LEGEND
® Receptor —Wells 25
Drawdown (ft) 50
0.5 75
5 100
10 200
15 — 300
20 400
r
a
Sourceso Esri, HERE, Garmin, Intermap, increm nt P C rp., GEBC
In I n In I IIIIdllll III I, IIIII
UBGS��� FAO NPS����NRCAN, GeoBam IILG, Ncl Kadlasiter N liJ Ordnance
Survey, Esri Japan, METI, Esri China (Hong Kong), swisstopo,
Open'StreetMap contributors, and the GIS User Community
DATA SOURCES: State Plane Coordinate System,
Zone: North Carolina (FIPS 3200), NAD 1983 2011, feet
MODEL PREDICTED DRAWDOWN
FROM DEWATERING IN THE
SOUTH PIT
N
0 0.5 1
MILES
PIEDMONT FN
Lit 141VM
FIGURE 9d
P ATH: C:\USERSIJTROYER\DESKTOP\PROJECTS1002 HASTINGSIGIS\CONTOURS FIGURE.MXD-USER: JTROYER - DATE: 612612019

lafhd 15
o i II'. • 1
� �lilllll�l� ply i'
� Illloc:lll/ IIII�I�I
OIIIO�,I QI j1011�i/l
�I,IQII /III II rl
' lol�lp/IIII Illrr
IIIIIIIIIIIIIIIIII IIIII Illlr Ilr
IIII Dill iiil �li�� 10�j1o�ll III
IIII IIII IIII IIIII �j01 II��III��
;��� � ,i IIIIIIIIIIIIIIIIII IIIII I II rl i - .
II �/ICI Illlllllll III/�III I �I
., n I� IIII'' I�/�II� IIIIIII�IIII II �
� IIII I/rllll%II�IIIIIII�III��III/ "' u II/I/r 111 I/III 1/I i�il�►-_ .
���ji�l�lllll�ll�iill�l���jl� II III
I I I�r
/I/IIIII/II/ /j01 IIIII/Illlr
/IIII III /I II 10!�
10�
i
Sources: Esri, HERE, Garmin,
Intermap, increment P Corp.,
GEBCO, USGS, FAO, NIPS,
NRCAN, GeoBase, IGN,
LEGEND
® Planned Pits
0 Delineated Wetlands
Q Site
Q Model Domain
DATA SOURCES: State Plane Coordinate System,
Zone: North Carolina (FIPS 3200), NAD 1983 2011, feet
HDR DELINEATED WETLANDS
LOCATION AND NAME OF DELINEATED
WETLANDS INSIDE THE SITE
N
0 0.2 0.4
MILES
PIEDMONT FN
511 "4 0IA
FIGURE 10
PATH: C:\USERSIJTROYER\DESKTOP\PROJECTS\004 PIEDMONT LITHIUM MINE%GISIPIGURE 9.MXD - USER: JTROYER - DATE: 6/2412019

N Stream 1g
1e
r
m
�a
5�
III
1112 T
-_j
Sources: EII ii, HERE, ,Garmin, Interrtli Alin I�eil�ilein II I'orp., EBCO,
USGS, FAO, NPS, NR'- GeoBase, IGN, Kadaster NL, Ordnance
Survey, Esri Japan, METI, Esri China (Hong Kong), swisstopo,
OpenStreetMap contributors, and the GIS User Community
E14
Sources: Esri, HERE, Garmin,
Intermap, increment P Corp.,
GEBCO, USGS, FAO, NPS,
NRCAN, GeoBase, IGN,
LEGEND
® Planned Pits
Q Site
Q Model Domain
Streams
Stream 2
Stream 3
Stream 1
Total Flow Measurement
DATA SOURCES: State Plane Coordinate System,
Zone: North Carolina (FIPS 3200), NAD 1983 2011, feet
HEIR STREAM REACHES
LOCATION AND NAME OF STREAM
REACHES
N
0 0.5 1
MILES
PIEDMONT FN
Lit 141UM
I9[e111111C MMI
PATH: C:\USERSIJTROYERIDESKTOP\PROJECTS\004 PIEDMONT LITHIUM MINE\GIS\FIGURE 10.MXD - USER: JTROYER - DATE: 612412019

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