NCD003162542_Badin Business Park_Corrective Action2_20231211

Badin Business Park LLC
201 Isabella Street
Suite 500
Pittsburgh, PA 15212-5858 USA
Tel: [phone]
December 11, 2023
Robert C. McDaniel
Hazardous Waste Section
North Carolina Department of Environmental Quality
217 West Jones Street
Raleigh, NC 27699
Re: Hydrogeological Conceptual Model Site Validation
Report Badin Business Park LLC, Badin, North
Carolina EPA ID: NCD 003 162 542
Dear Mr. McDaniel,
Please find accompanied with this letter an electronic link to access the Hydrogeological Conceptual Site
Model Validation Report, dated December 2023, for the Badin Business Park. The Validation Report
addresses a comprehensive facility-wide groundwater monitoring event completed during May and June
of 2023 as well as data gaps identified in the HCSM Update and comments from NCDEQ.
Should you have any questions or comments, please contact Jason Mibroda of Alcoa at [phone] at
your convenience.
Respectfully,
Robyn L. Gross
Director, Asset Management Americas
Badin Business Park LLC
Cc:
Randy Bush, Alcoa
Jason Mibroda, Alcoa
Kim Caulk, NCDEQ
Julie Grzyb, NCDEQ
John Hennessey, NCDEQ
Richard Rogers, NCDEQ
Andrew Pitner, NCDEQ

Hydrogeological
Conceptual Site Model
Validation
Badin Business Park
Badin, North Carolina
Prepared for:
Alcoa Corporation
Prepared by:

December 2023
Hydrogeological Conceptual Site Model Validation – Badin Business Park
Acronyms
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Table of Contents
Executive Summary ........................................................................................................................... vi
1 Introduction ..........................................................................................................................1
1.1 Key Findings.............................................................................................................................. 1
2 Hydrogeologic Conceptual Site Model Summary .....................................................................2
3 Objectives..............................................................................................................................4
3.1 Methods .............................................................................................................................. 4
4 Groundwater Flow and COI Distributions ................................................................................9
4.1 Groundwater Flow .............................................................................................................. 9
4.2 COI Distributions .................................................................................................................... 13
4.2.1 Fluoride ................................................................................................................ 13
4.2.2. Free Cyanide ....................................................................................................... 19
4.2.3 Trichloroethylene ................................................................................................ 22
4.3 Summary ........................................................................................................................... 22
5 Comprehensive Geochemical Analysis .................................................................................. 24
5.1 Fluoride Analytical Method Bias ....................................................................................... 24
5.2 Identification of Fluoride Attenuation ................................................................................... 25
5.3 Validation of Groundwater-Surface Water Mixing ................................................................ 26
5.4 Fluoride Attenuation Mechanisms ........................................................................................ 28
6 Conclusions ......................................................................................................................... 30
7 References ........................................................................................................................... 32

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Acronyms
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List of In-Text Tables
Table 3-1 Groundwater Analytical Methods
Table 4-1 Water Quality Standards
Table 4-2 Historical Trichloroethylene Results (µg/L)

List of Attached Tables
Table D-1 Vertical Groundwater Gradients
Table E-1 Badin Narrows Dam and Outfall 002 & 011/012 Stilling Well Lake Level Calibration
List of In-Text Figures
Figure 2-1 Site Layout
Figure 4-1 May 2023 PWR Groundwater Elevation
Figure 4-2 May 2023 Groundwater Elevations in Fill and Vertical Gradients
Figure 4-3 May/June 2023 Fluoride Analytical Results (PWR)
Figure 4-4 May/June 2023 Fluoride Analytical Results (Soil and Fill)
Figure 4-5 Groundwater Fluoride Concentrations Trends – North Plant
Figure 4-6 Groundwater Fluoride Concentrations Trends – ABL and OBL
Figure 4-7 May/June 2023 Free Cyanide Analytical Results (PWR)
Figure 4-8 May/June Free Cyanide Analytical Results (Soil and Fill)
Figure 4-9 Trichloroethylene Concentration Trends
Figure 5-1 Comparison between Fluoride Results from Different Analytical Methods
Figure 5-2 Comparison of Groundwater Data and Calculated Dilution Line
Figure 5-3 Mixing Model for Former Main Plant
Figure 5-4 Mixing Model for ABL and West Fill Area
Figure 5-5 Non-conservative Mixing Model Results

List of Attached Figures
Figure F-1 Comparison of Fluoride Analyzed by SW846 Method 9056A (IC) and SM 4500-F-C (ISE)
Figure F-2 Difference between Method 9056A and 4500-F-C Results
Figure F-3 IC Fluoride Bias Compared to Carbonate Ion Concentration
Figure G-1 Comparison of Groundwater Data and Calculated Dilution Line
Figure G-2 Fluoride Mineral Saturation Indices
Figure G-3 Stable Calcium Minerals – Sample ABP-MW023
Figure G-4 Non-conservative Mixing Model
Figure G-5 Non-conservative Mixing Model Results
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Acronyms
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List of Appendices
Appendix A Data Packages and Laboratory Reports
Appendix B 2023 Well Survey and Construction Details
Appendix C Groundwater Geochemistry Data
Appendix D Vertical Groundwater Gradient Calculations
Appendix E Badin Lake Level Calculations
Appendix F Fluoride Analytical Method Assessment
Appendix G Geochemical Modeling Assessment

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Acronyms
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Acronyms
ABL Alcoa Badin Landfill
CDTA cyclohexylenediaminetetraacetic acid
CMS Corrective Measures Study
COI contaminant of interest
GWB Geochemist’s Workbench® (software)
HCSM Hydrogeological Conceptual Site Model
IC ion chromatography
ISE ion selective electrode
MH manhole
mg/L milligrams per liter
µg/L micrograms per liter
NAVD88 North American Vertical Datum 1988
NCAC North Carolina Administrative Code
NCDEQ North Carolina Department of Environmental Quality
OBL Old Brick Landfill
PWR partially weathered rock
RCRA Resource Conservation and Recovery Act
RFI RCRA Facility Investigation
TCE trichloroethylene
USEPA United States Environmental Protection Agency
VOC volatile organic compound

Trademarks, trade names, company, or product names referenced herein are used for identification
purposes only and are the property of their respective owners.

Hydrogeological Conceptual Site Model Validation – Badin Business Park
Executive Summary
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Executive Summary
Comprehensive groundwater sampling conducted at the Badin Business Park in May and June of 2023
has demonstrated that the footprint of impacted groundwater remains steady, and concentrations of
primary constituents in groundwater have decreased substantially or remained stable in most locations
since 1999. Key insights gathered from a review of this data are detailed below.
Free cyanide only exceeds groundwater criteria in three wells that are screened in fill at the On-site
Landfill and West Fill areas. Free cyanide concentrations at the boundary of the Facility are all below
criteria.
The highest groundwater fluoride concentrations are present in isolated areas of fill, and impacts have
migrated downward into the more transmissive partially weathered rock (PWR) that underlies all of the
Facility. A detailed geochemical analysis indicates that fluoride is attenuated when groundwater mixes
with other water types; as a result of the attenuation, fluoride is mineralized and immobilized.
Water types that can mix with groundwater at the Facility include clean groundwater flowing from the
hillside west of the former Main Plant, precipitation that infiltrates into soils, and water from Badin Lake
to the east. Comparison of lake levels with groundwater elevations, coupled with ion ratios that define
mixing trends between water types, supports this conceptual model and indicates that for the majority
of the Site (in particular the PWR) water flows from the lake into the Facility. Based on the combination
of this recharge and the vertical gradients, groundwater travels through the PWR and beneath the Alcoa
Badin Landfill (ABL), and groundwater from the Site ultimately discharges on the floodplain of Little
Mountain Creek.
Fluoride is below criteria in all monitoring wells around the perimeter of the ABL and on the floodplain
of Little Mountain Creek, indicating that the combination of natural attenuation and active remediation
measures implemented at the toe of the Alcoa/Badin municipal landfill are effective at capturing
impacted groundwater and preventing the migration of constituents of interest to Little Mountain
Creek.

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Introduction
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1 Introduction
This Hydrogeological Conceptual Site Model (HCSM) Validation Report (Report) has been prepared for
Badin Business Park LLC, a subsidiary of Alcoa Corporation (Alcoa). The Badin Business Park Facility
(Facility or Site), formerly known as the Badin Works Facility, and associated properties consist of the
former Main Plant, Alcoa Badin Landfill (ABL), and Old Brick Landfill (OBL). The Facility is located at 293
Highway 740 in Badin, Stanly County, North Carolina. An HCSM Update was completed in December
2022 (EHS Support, 2022) and was accepted by the North Carolina Department of Environmental Quality
(NCDEQ) in a letter dated March 9, 2023. A summary of the HCSM is provided in Section 2.
To address data gaps identified in the HCSM Update and comments from NCDEQ, a comprehensive
facility-wide groundwater monitoring event was completed during May and June of 2023 following
procedures outlined in the Groundwater Sampling Plan (Civil Environmental Consultants [CEC], 2023).
The May/June 2023 comprehensive groundwater sampling event was supplemented with an extended
suite of geochemical parameters utilized to verify vertical and horizontal groundwater flow pathways
and constituent attenuation mechanisms presented in the HCSM Update. Data packages and laboratory
reports from the May/June 2023 sampling event are provided in Appendix A.
1.1 Key Findings
Key findings from a review of the May/June 2023 comprehensive sampling data are provided below.
• Badin lake water infiltrates into the groundwater system and provides benefits to groundwater
quality by lowering concentrations through mixing and chemical reactions that immobilize
fluoride.
• Fluoride concentrations in groundwater are stable or decreasing at almost every location since
the Resource Conservation and Recovery Act (RCRA) Facility Investigation (RFI) was conducted in
1999.
• Fluoride distributions are consistent with historical results, and the area of impacts has not
increased in size.
• Hydrogeological conditions facilitate mixing between water sources of differing characteristics,
and fluoride attenuation is occurring along flow paths. Mixing of different water types leads to
geochemical reactions that mineralize fluoride.
• Free cyanide concentrations are below criteria and are non-detect in most locations; therefore,
free cyanide is not a risk driver for groundwater at the Facility.
• Trichloroethylene (TCE) concentrations continue to improve in the northern area of the former
Main Plant.

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2 Hydrogeologic Conceptual Site Model Summary
Detailed discussion of the Facility background, geology, and hydrogeology is provided in the HCSM
Update (EHS Support, 2022) and only points pertinent to the present study are provided for context.
Areas where past operations occurred include the 123-acre former Main Plant, with industrial materials
disposed of at discrete areas of the plant and in the 14-acre ABL, located 500 feet southwest of the
former Main Plant, and the 3-acre OBL located 0.75 miles northeast of the former Main Plant. The
former Main Plant was built on an area of engineered cut and fill that was leveled to an elevation of
approximately 520 feet relative to the North American Vertical Datum 1988 (NAVD88). The former Main
Plant area encompasses the on-site landfill, Pine Tree Grove area, TCE area, and West Fill area. The
elevation increases immediately west of the former Main Plant to over 600 feet NAVD88 (Figure 2-1).
The former Main Plant is bordered by Badin Lake to the east, which is a man-made flooded valley
constructed in the early 1900s for generating hydroelectric power. The maximum surface water
elevation of Badin Lake is 508.78 feet (NAVD88), which is controlled by the full lake point at the Badin
Narrows Dam. The ground surface elevation decreases south of the former Facility and ABL to less than
470 feet (NAVD88) on the floodplain of Little Mountain Creek (Figure 2-1). The elevation differential
between Badin Lake and the floodplain of Little Mountain Creek provides the hydraulic potential for
water to flow through fractured and partially weathered rock (PWR) from the lake toward the floodplain
of Little Mountain Creek.

Figure 2-1 Site Layout
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Geologic units at the Facility are PWR (including fractured rock), soil (including saprolite and residual
soil), and fill. Fill is either composed of native soils or is a mixture of native soil and anthropogenic debris
that may include industrial materials. PWR has moderate hydraulic conductivity and is extremely
conductive locally due to fracturing; whereas saprolite and residual soil have very low hydraulic
conductivity.
PWR is the only unit that is continuous across the former Main Plant and ABL. PWR and anthropogenic
fill are the primary units where groundwater movement can occur. Areas of fill are limited to isolated
ravines or drainages that were filled during Facility development and operations, so groundwater can
migrate from fill where there are downward vertical groundwater gradients into PWR. For this reason,
the sitewide hydrogeological conditions that control fate and transport of contaminants in groundwater
are described using data from a network of PWR wells. Groundwater elevations in wells screened in fill
are used for understanding how isolated areas of fill interact with the broader groundwater system in
the PWR.
Groundwater elevation data from PWR wells indicate groundwater at the former Main Plant is
recharged by Badin Lake to the east and a flow system originating on the hillside to the west. The two
flow systems converge near the shoreline of Badin Lake and flow southward toward the ABL.
Groundwater primarily flows toward the floodplain of Little Mountain Creek, where there is potential
for groundwater to discharge onto the floodplain or at Outfall 005 as evidenced by strong upward
vertical groundwater gradients in this location. A groundwater collection trench at the toe of the ABL
has gone through several upgrades and is effective at mitigating groundwater impacts to the floodplain
of Little Mountain Creek, as evidenced by annual geophysical surveys of subsurface conductivity that
indicate a decreasing footprint of impacted groundwater.
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Objectives
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3 Objectives
In the present study, hydrogeological and geochemical data collected in May/June 2023 are used to
validate the HCSM described above. Data are also used to expand the conceptual understanding of how
discrete areas of groundwater in Fill areas at the Facility interact with the PWR groundwater system,
how contaminant of interest (COI) concentrations have varied over time, and what are the key
attenuation mechanisms. A data report including laboratory reports, analytical reports, and sample
quality assurance metrics is provided in Appendix A.
Specific objectives for the comprehensive geochemistry sampling coupled with groundwater elevation
and COI measurements included the following:
• Verify the groundwater flow and transport conceptualization using groundwater and surface
water elevation measurements.
• Determine the current distribution of fluoride and free cyanide across the former Main Plant,
ABL, and OBL and determine the current distribution of volatile organic compounds (VOCs) in
the TCE area.
• Assess potential bias in the fluoride analytical testing technique and make recommendations for
future sampling.
• Determine horizontal and vertical groundwater gradients between fill areas and underlying PWR
supplemented with comprehensive geochemical parameter sampling to determine groundwater
mixing ratios from fill to PWR.
• Complete the following assessments for the areas listed below:
o ABL area – comprehensive geochemical parameter analysis to verify the groundwater flow
paths, mixing ratios, and attenuation factors upgradient of the landfill toward the Little
Mountain Creek floodplain; verify the HCSM.
o OBL area – comprehensive geochemical parameter analysis to determine the groundwater
flow paths, mixing ratios, and attenuation factors upgradient of the landfill toward Badin
Lake. Verify the role of PWR versus fill for retaining and/or transmitting groundwater.
o Pine Tree Grove area – comprehensive geochemical parameter analysis to determine the
groundwater flow paths, mixing ratios, and attenuation factors between Pine Tree Grove
and Badin Lake.
o Former Main Plant area – comprehensive geochemical parameter analysis to verify HCSM
and demonstrate mixing between former Main Plant groundwater and Badin Lake.
o West Fill area – comprehensive geochemical parameter analysis to verify HCSM;
demonstrate role of PWR for transmitting groundwater; demonstrate role of fill for retaining
groundwater.
o TCE area – comprehensive geochemical parameter analysis to verify HCSM and demonstrate
mixing between former Main Plant groundwater and Badin Lake.
3.1 Methods
The Groundwater Sampling Plan (CEC, 2023) provides a detailed outline of sampling locations, field
implementation procedures, and data management protocols and should be referred to for details
pertaining to the May/June 2023 sampling event methods. Details of the Groundwater Sampling Plan
pertinent to the present report are summarized below.
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The May/June 2023 sampling event included a suite of comprehensive geochemistry parameters
collected from 37 locations to provide lines of evidence to support the HCSM update (EHS Support,
2022) and refine the understanding of horizontal and vertical COI fate and transport in different areas of
the Facility. Additional comprehensive geochemical parameters from Little Mountain Creek collected for
the ongoing Baseline Ecological Risk Assessment work were also utilized in the analysis, along with a
sample from the storm sewer (manhole [MH] 2.320) and groundwater sampled from test pits dug in the
former Main Plant as part of an ongoing treatability study. Depth to groundwater measurements were
obtained at 101 monitoring wells and piezometers to verify the HCSM, and groundwater was sampled
for COIs in 76 monitoring wells and piezometers to update the current understanding of COI
distributions and further development of the HCSM for COI fate and transport. June 2023 sampling
locations are shown on Figure 3-1.
A stilling well was installed in Badin Lake adjacent to the Facility and a reference point was surveyed for
future lake level monitoring. The well was installed after groundwater measurements were made;
therefore, Badin Lake level data used in this study was obtained from public sources 1; the measurement
datum was surveyed and tied to the site monitoring well network to verify accuracy of the vertical lake
level monitoring datum. Several monitoring wells were also surveyed by a North Carolina licensed
Professional Land Surveyor to verify the top of casing elevations are reported to a consistent vertical
datum. A revised monitoring well construction table including survey data is provided in Appendix B.

1 http://badin.lakesonline.com/Level/
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Figure 3-1 May/June 2023 Sampling Locations

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Depth to water measurements were obtained on May 23 and May 24, 2023, and groundwater and
surface water sampling was completed by mid-June. Groundwater samples were collected from
approximately 76 locations and analyzed for the primary COIs (i.e., fluoride and available cyanide). VOCs
were analyzed in six wells at the northern end of the former Main Plant (ABP-MW004, ABP-MW008,
ABP-MW009, ABP-MW016, ABP-MW110, ABP-MW200) to assess the current extent of TCE in
groundwater. Data were compared to previous Facility-wide sampling event data. Facility-wide sampling
events were previously conducted in the areas listed below:
• The ABL, OBL, and former Main Plant during the RFI in September and October 1999 (MFG Inc,
2001)
• The former Main Plant in February 2006 (BHE Environmental Inc., 2006)
• The former Main Plant in August 2011 (BHE Environmental Inc., 2011)
• The ABL, OBL, and former Main Plant during the Corrective Measures Study (CMS) Phase 3 over
several months between June 2011 and August 2012 (Environeering Inc., 2012)
Fluoride was analyzed using two methods: SW846 Method 9056A by ion chromatography (IC) and SM
4500-F-C by ion selective electrode (ISE). Site fluoride analytical results have been historically analyzed
using an IC method. As described in the SW846 Method 9056A documentation, the IC method can be
prone to interferences on the fluoride peak by organic acids and ions that elute off the column near the
fluoride peak. Landfills are widely known to be associated with organic acids and alkaline conditions
where carbonate ions may dominate (Baedecker and Bach, 1979); therefore, comparison of the two
fluoride analytical techniques was undertaken to assess potential bias in fluoride analytical results.
The comprehensive geochemical sampling included major cations (sodium, calcium, potassium,
magnesium), anions (sulfate, chloride, nitrate, nitrite), and alkalinity to assess mixing scenarios between
different water sources. Additional parameters were included to assess geochemical reactions that may
affect fluoride attenuation. Specifically, orthophosphate, silica, aluminum, iron, manganese, dissolved
organic carbon, and total suspended solids were analyzed. Analytical methods are listed on Table 3-1.
The field parameters listed in Table 3-1 were also measured at the time of sampling, except for samples
ABP-SW001 through ABP-SW003, where pH values were obtained from the laboratory. The 2023
groundwater chemistry data used in this assessment are provided in Appendix C. Data were assessed
and geochemical calculations were performed using Geochemist’s Workbench® (GWB) software
(Bethke, 2022).
Table 3-1 Groundwater Analytical Methods
Analyte(s) Method
Free Cyanide 1677
Fluoride 9056A and 4500F
Bromide, Chloride, Sulfate 9056A
Nitrate, Nitrite (as Nitrogen) 353.2
Orthophosphate 4500PF
Alkalinity (Total, Carbonate, Bicarbonate) as calcium
carbonate (CaCO3)
2320B
Silica (as SiO2) 6010D
Aluminum, Calcium, Iron 2, Magnesium, Manganese,
Potassium, Sodium
6020B
Dissolved Organic Carbon 5310B

2 Iron was measured as ferrous iron by method 3500FED for treatability study samples.
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Analyte(s) Method
Total Suspended Solids 2540D
Dissolved Oxygen, Specific Conductance, pH,
Temperature, Oxidation Reduction Potential
Field Measurement
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4 Groundwater Flow and COI Distributions
Results of the May/June 2023 comprehensive sampling event are provided in the following section.
4.1 Groundwater Flow
Several wells in the ABL, OBL, and former Main Plant areas were resurveyed in August 2023 to verify
that groundwater elevations are reported on a consistent vertical datum (NAVD88). A well construction
table with revised top of casing elevations is provided in Appendix B. Previously, wells at the OBL, ABL,
and several wells at the former Main Plant areas were reported on the National Geodetic Vertical Datum
of 1929 (NGVD29), which is approximately 0.87 feet higher than NAVD88. The resurvey effort did not
affect previous conclusions about overall groundwater flow directions.
May 2023 groundwater elevations were contoured for wells screened in PWR and/or rock, or with
screen intervals that include soil or saprolite and PWR (Figure 4-1). This method was used because soil
and saprolite are not expected to contribute significantly to water levels in these cross screened wells
due to the relatively low hydraulic conductivity of these units compared to PWR (EHS Support, 2022). As
indicated on Figure 4-1, groundwater contours follow topography and are closely spaced on the hillside
west of the Main Plant and are more widely spaced on the flat area of the Main Plant. Along the
shoreline of Badin Lake, groundwater contours flatten and curve southward toward the ABL and slope
south of Badin Lake. The overall flat contours along the shoreline of Badin Lake indicate limited potential
groundwater flow toward Badin Lake. Groundwater contours steepen to the south beneath the ABL and
on the slope south of Badin Lake. Overall, the distribution of groundwater contours are consistent with
topographically driven groundwater flow in the PWR toward the floodplain of Little Mountain Creek.
Groundwater elevations in soil and fill wells are shown on Figure 4-2. Groundwater elevations in PWR
wells that were used to determine relative (upward or downward) vertical groundwater gradients, along
with the qualitive vertical gradient results, are also shown on Figure 4-2. The method and detailed
results for calculating vertical groundwater gradients are provided in Appendix D. Groundwater
contours were only developed for PWR (not fill wells) because PWR is the only contiguous unit present
across the entire Facility, and there is evidence of locally perched areas of groundwater in fill.
Groundwater elevations were compared to the elevation of Badin Lake surface water. Details of the
survey and elevation calculations are provided in Appendix E. A Badin Lake level of 508.43 (feet
NAVD88) was calculated from the Cube Hydro data reported for May 24, 2023, and is used in this report.
During times when the lake level rises, lake water infiltrates the groundwater system and mixes. When
the lake level drops, the lake water stored in the shoreline has a potential to seep out. This process is
commonly referred to as “bank storage”, where lake water enters the soil during periods of high water
levels and then redrains back into the lake during lower water levels.
From May 1 through June 30, 2023, the lake level ranged from 507.76 feet to 508.60 feet NAVD88 (less
than a one-foot variation). This result indicates that significant gradient changes between the lake level
and groundwater elevation do not occur, and any flux toward the lake is minimal. Badin Lake level data
recorded every minute for the month of May was provided by Cube Hydro, and the average lake level
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was 508.44 feet NAVD88 3 for the month, almost identical to the value used to develop groundwater
contours.
Groundwater systematics in May 2023, consistent with those presented for September 2022 and
October 2022 (EHS Support, 2022), indicate the following:
• Groundwater at higher elevations on the western side of the former Main Plant flows eastward
toward Badin Lake through PWR.
• The groundwater elevation in PWR and fill adjacent to and inland (west) of the shoreline of
Badin Lake is generally within the margin of measurement error or lower than the Badin Lake
level. The flat groundwater gradients adjacent to the lake indicate that groundwater flux from
PWR to the lake is negligible.
• Lake water infiltrates into and mixes with groundwater in PWR. Lake water infiltration to
groundwater is consistent with large decreases in fluoride and free cyanide concentrations near
the lake shore (Section 4.2) and current and historical Badin Lake surface water sampling results
that indicate no Facility COIs are present in Badin Lake surface water (Environeering, 2012).
Badin Lake surface water mixing with groundwater is further supported by geochemical
fingerprinting discussed in Section 5.
• Near the Badin Lake shoreline in the former Main Plant area, groundwater in the PWR flows
south-southeast toward the ABL and hillside south of Badin Lake. Groundwater also flows
toward the floodplain of Little Mountain Creek.
o Mixing and geochemical reactions (Section 5) along the flow path results in COI
concentrations below criteria in groundwater that flows beneath the ABL.
o Upward groundwater gradients at the toe of the ABL mix with leachate and create seeps at
the toe of the ABL.
o Groundwater seeps at the Little Mountain Creek Floodplain are managed by a barrier wall
and groundwater collection trench downgradient and at the toe of the ABL.
o The efficacy of the groundwater capture system is demonstrated by the decreasing
electrical conductivity (correlated with the fluoride concentration in groundwater) over time
(EHS Support, 2022), and the absence of COIs above criteria in groundwater downgradient
of the ABL (Section 4.2).

3 Calculated using the average lake level of 540.76 feet NGVD29 compared to a full lake datum of 541.10 feet
NGVD29, which gives a difference of 0.34 feet below the full lake level. This difference is compared to the full lake
datum in feet NAVD88.
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Figure 4-1 May 2023 PWR Groundwater Elevation
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Figure 4-2 May 2023 Groundwater Elevations in Fill and Vertical Gradients
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4.2 COI Distributions
This section describes current distributions of primary COIs (i.e., fluoride, free cyanide, and TCE) in
groundwater at the Facility. Current concentrations are compared to historical results where historical
data is available. Groundwater results are compared to Title 15A of the North Carolina Administrative
Code (NCAC) Subchapter 2L standards (“NC 2L standards”), and surface water samples are compared to
NCAC Rule 2B fresh surface water quality standards (“NC 2B standards”). Water quality standards are
listed in Table 4-1.
Table 4-1 Water Quality Standards
Parameter NC 2L Groundwater Standard NC 2B Class I-V Surface Water
Standard
Fluoride 2 mg/L 1.8 mg/L
Free Cyanide 0.070 mg/L N/A
Available or Total Cyanide N/A 0.005 mg/L
TCE 3 µg/L 2.5 µg/L
Notes:
mg/L = milligrams per liter
N/A = not applicable
µg/L = micrograms per liter
TCE = trichloroethylene
4.2.1 Fluoride
Groundwater fluoride results were analyzed by SW846 Method 9056A and SM 4500-F-C. Results of both
methods for PWR and Fill/Soil wells are provided on Figure 4-3 and Figure 4-4, respectively.
Consistent with historical results, fluoride concentrations in groundwater at the ABL exceeded the NC 2L
standard only in piezometers screened within ABL waste materials (ABL-PZ-15 and ABL-PZ-17). Fluoride
has not previously (or currently) been detected above the NC 2L standard in any perimeter groundwater
monitoring well surrounding the ABL (MW-1 through MW-6). In the May/June 2023 event, fluoride was
below criteria in floodplain piezometers ABL-PZ03S and ABL-PZ18RD. The shift from downward to
upward groundwater gradients beneath the ABL supports the CSM whereby upward groundwater
gradients at the toe of the ABL provide a mechanism for groundwater to contact fill materials where
saprolite soils are absent and more conductive alluvial deposits are present beneath the toe of the ABL.
In these locations, upward vertical groundwater gradients form seeps that are managed by a barrier wall
and capture trench system. The mitigation measures are demonstrated to be effective through
geophysical measurements of conductivity on the floodplain of Little Mountain Creek that show a
decreasing footprint of more conductive material (EHS Support, 2022).
Fluoride concentration contours in groundwater at the former Main Plant for PWR and Fill/Soil wells are
provided on Figure 4-3 and Figure 4-4, respectively. Consistent with historical results, fluoride is
detected above NC 2L groundwater standards at the former Main Plant in the vicinity of the On-Site
Landfill, the Pine Tree Grove area, and the West Fill area. Concentrations are highest in the isolated
areas of fill (Figure 4-4) and are significantly lower in underlying PWR (Figure 4-3), consistent with
downward groundwater gradients from fill to PWR in most locations (Figure 4-2). The large difference in
concentrations supports the CSM whereby only limited seepage of groundwater from fill to the
underlying PWR occurs, coupled with geochemical reactions that mineralize and immobilize fluoride
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(Section 5). Where there are upward groundwater gradients at the southwest corner of the On-site
Landfill, upwelling clean water from the PWR reacts with impacted water in fill and there are large
concentration decreases of fluoride over a short distance (Figure 4-2 through Figure 4-4). Away from the
On-site landfill at the shoreline of Badin Lake, fluoride concentrations decrease by orders of magnitude
in PWR and Fill, and are at background levels in Badin Lake surface water (Figure 4-3 and Figure 4-4). At
all wells closest to the Badin Lake shoreline where fluoride is above criteria, water level elevations are
within the range of lake elevations, except at ABP-MW112 and ABP-MW025 screened in fill composed of
industrial materials (Figure 4-1 through Figure 4-4). Groundwater at these locations is likely perched,
given that all surrounding wells (including those more inland) have groundwater elevations within the
margin of measurement error at or below the lake level, and fluoride in Badin Lake surface water is at
background levels immediately adjacent to these locations.
Figure 4-5 and Figure 4-6 show locations where historical fluoride analytical data is available for
comparison with current results. The figures are divided into areas with higher, moderate, and lower
concentrations due to the orders of magnitude differences in concentrations in isolated fill areas
compared to surrounding areas that would obscure the comparison. Compared to historical
distributions, fluoride concentrations are stable to declining at most locations.

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Figure 4-3 May/June 2023 Fluoride Analytical Results (PWR)
Hydrogeological Conceptual Site Model Validation – Badin Business Park
Groundwater Flow and COI Distributions
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Figure 4-4 May/June 2023 Fluoride Analytical Results (Soil and Fill)
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Groundwater Flow and COI Distributions
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Note: Bar color indicates timeframe that sample was collected.
Figure 4-5 Groundwater Fluoride Concentrations Trends – North Plant
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Note: Bar color indicates timeframe that sample was collected.
Figure 4-6 Groundwater Fluoride Concentrations Trends – ABL and OBL
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4.2.2. Free Cyanide
Groundwater free cyanide results for PWR and Fill/Soil wells are provided on Figure 4-7 and Figure 4-8,
respectively.
Historically, total cyanide or available cyanide analytical results were reported for Facility groundwater.
Prior to September 2019, there were no United- States Environmental Protection Agency (USEPA)-
approved analytical methods for free cyanide (State of North Carolina, 2022). Following adoption of a
USEPA-approved method for analysis of free cyanide, a NC 2L groundwater standard of 0.070 milligrams
per liter (mg/L) was established for free cyanide. For this reason, a robust dataset for historical free
cyanide concentrations is not available for comparison of trends.
Free cyanide is non-detect in most locations. Free cyanide exceeds criteria in only three locations (two in
the On-Site landfill and one in the West Fill area). All groundwater locations adjacent to Badin Lake and
Little Mountain Creek were non-detect for free cyanide, indicating free cyanide in groundwater is not a
driver for risk at the Facility.

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Figure 4-7 May/June 2023 Free Cyanide Analytical Results (PWR)
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Figure 4-8 May/June Free Cyanide Analytical Results (Soil and Fill)
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4.2.3 Trichloroethylene
TCE has historically been detected in wells located in the northern portion of the former Main Plant
area. TCE concentrations remain above NC 2L standards but have declined significantly since the RFI in
2000 and CMS Phase 3 in 2011 in all wells except ABP-MW004, where concentrations fluctuate around
historical ranges (Table 4-2 and Figure 4-9). Well ABP-MW009 has always had the highest TCE
concentration at the Site. TCE in groundwater was 190 micrograms per liter (µg/L) during the RFI and is
45 µg/L currently. TCE detected in well ABP-MW110 (screened in fill near the shoreline of Badin Lake)
declined from 6.5 µg/L (7.1 µg/L in duplicate sample) in July 2018 to 5.7 µg/L in June 2023, and is now
marginally above the NC 2L standard of 3 µg/L. The groundwater elevation at ABP-MW110 (507.44 feet
NAVD88) is almost one foot lower than the level of Badin Lake (508.43 feet NAVD88), indicating that
lake water is infiltrating the groundwater system at this location and risk to the lake from TCE is
negligible.
Table 4-2 Historical Trichloroethylene Results (µg/L)
Sep. 2000 Nov./Dec. 2011 7/9/2018 June 2023
ABP-MW004 24 40 8.5 43
ABP-MW008 <5 NM NM < 0.2
ABP-MW009 190 86 66.1 45
ABP-MW016 26 19 8.6 11 / 9.8
ABP-MW110 NM NM 6.5 / 7.1 5.7
ABP-MW200 NM NM NM <0.2

Figure 4-9 Trichloroethylene Concentration Trends
4.3 Summary
In summary, the highest COI concentrations in groundwater are in wells and piezometers screened in
discrete areas of fill, indicating localized areas of fill are the source of groundwater impacts. Downward
vertical groundwater gradients from fill to PWR at the West Fill area and Pine Tree Grove area have
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impacted groundwater in PWR; however, attenuation occurs rapidly over a short distance. At the West
Fill area, mixing with groundwater in PWR attenuates COIs. At the Pine Tree Grove area, Badin Lake
water mixes with groundwater in both PWR and fill and attenuates COIs. Upward vertical gradients from
PWR to fill at the toe of the On-site landfill attenuates COIs. At the ABL, COIs in groundwater are only
above criteria within the fill and impacted groundwater that exits the landfill is captured and mitigated.
The following points support this summary:
• Groundwater fluoride concentrations are consistently higher in fill than the underlying PWR.
Groundwater fluoride is above criteria in fill and underlying PWR at the On-site Landfill, Pine
Tree Grove area, West Fill area, and the interior of the ABL. Free cyanide is above groundwater
criteria only in three wells at the Facility.
• Groundwater in areas of fill is laterally discontinuous and drains downward into the underlying
PWR as evidenced by downward vertical gradients. Lower fluoride concentrations and more
restricted lateral distributions of fluoride in PWR groundwater indicate significant attenuation
occurs as groundwater moves from fill to PWR. This is due to limited groundwater mass flux
from high porosity and low permeability residual soils and saprolite into the underlying high
permeability and low porosity PWR.
• The only locations where there are upward vertical gradients are at the downgradient edges of
the On-site Landfill and the ABL.
o At the On-site Landfill, upwelling of clean PWR groundwater into fill at ABP-MW-06A
(fluoride = 0.26 mg/L) and ABP-MW217 (fluoride = 1.4 mg/L) prevents southeastward
migration of fluoride concentrations in groundwater above criteria (Figure 4-1 through
Figure 4-4).
o At the ABL, upward vertical groundwater gradients on the floodplain of Little Mountain
Creek are observed at ABL-PZ03I/ABL-PZ03D well pairs and from periodic, flowing artesian
conditions at ABL-MW003 (Figure 4-2). Fluoride concentrations are below criteria in wells
upgradient of the ABL, around the ABL, and downgradient of the ABL on the floodplain of
Little Mountain Creek (Figure 4-3 and Figure 4-4). Fluoride is only above criteria in
piezometers screened in the ABL fill (ABL-PZ15 and ABL-PZ17; Figure 4-4). This indicates that
COIs at the ABL are locally sourced and that the barrier wall and capture trench
downgradient of the ABL are effective at managing flux of fluoride in groundwater toward
Little Mountain Creek.
The following sections leverage comprehensive geochemical analysis to describe the COI attenuation
processes.

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5 Comprehensive Geochemical Analysis
Section 4.1 discusses field water level measurement results that identify hydrogeological flow pathways
and locations where fluoride attenuation is occurring due to mixing of different water types. Section 4.2
provides lines of evidence that support the hydrogeological data using laboratory measurements of
fluoride concentrations. The following sub-sections provide the results of comprehensive geochemical
analyses of groundwater to identify fluoride attenuation mechanisms and provide an additional line of
evidence to validate the hydrogeological conceptualization.
5.1 Fluoride Analytical Method Bias
Potential bias in fluoride analytical methods was assessed to ensure that the magnitude of fluoride
concentrations in groundwater are accurate and to inform geochemical procedures for assessing
fluoride fate and transport. Fluoride was analyzed using two methods: SW846 Method 9056A (IC) and
SM 4500-F-C (ISE). Details of the assessment are provided in Appendix F.
Results show that the IC method is systematically biased high in samples with more than about 20-30
mg/L fluoride due to interferences from carbonate and possibly organic acids. Figure 5-1 shows that
fluoride IC results are systematically higher for samples where carbonate is also elevated. The selection
of the fluoride analytical method (i.e., IC or ISE) has limited influence on compliance decisions for dilute
groundwater and surface water, as there is no apparent bias at these low levels of fluoride. Bias in
fluoride analytical methods is primarily of concern when making decisions based on landfill leachate
data. In the context of the present report, ISE fluoride results are used when available 4 to determine
controls on fluoride fate and transport, as landfill leachate data are a critical component of the
geochemical assessment.
Note: Vertical axis show magnitude of bias in IC fluoride results compared to fluoride concentration and carbonate ion
concentration.
Figure 5-1 Comparison between Fluoride Results from Different Analytical Methods

4 Fluoride was not measured by ISE for MH-1, TP-1, TP-2, and ABP-MW038, so fluoride measured by IC was used for these samples in the assessment.
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5.2 Identification of Fluoride Attenuation
A conservative mixing model was performed on groundwater samples to evaluate if geochemical
reactions contribute to fluoride attenuation (in addition to dilution) by the mixing of different water
types. Two water samples (ABP-MW023 leachate and ABP-SW001 Badin Lake water) were selected as
opposite extremes in models to assess mixing processes (conservative mixing). The ABP-MW023
leachate sample represents a high fluoride extreme, and the Badin Lake sample represents a low
fluoride extreme. The sample from Badin Lake is also a useful proxy for assessing mixing between
leachate and clean groundwater in PWR that occurs where downward vertical gradients provide a
potential for mixing due to the compositional similarity of Badin Lake water to groundwater at
upgradient locations ABP-MW011, ABP-MW013, ABP-MW218, and ABL-MW211.
A model was completed to verify if fluoride attenuation is solely due to dilution or if another attenuation
process is occurring. The two extreme samples were mathematically mixed using GWB and assume no
other attenuation process occurs. If attenuation is only due to dilution, measured fluoride
concentrations should match the results of this mixing model. Differences between the model and
measured sample results indicates an attenuation process other than mixing/dilution is occurring
(Figure 5-2). Details of the assessment are provided in Appendix F. The key findings area:
• Conservative mixing (dilution) alone cannot account for fluoride attenuation (Figure 5-2).
• Decreased fluoride/sodium and calcium/sodium molar ratios relative to ideal mixing suggest
calcium is depleted during mixing, and that a calcium-fluoride phase is forming and attenuating
fluoride in addition to dilution by mixing.
• The conservative mixing model indicates dilution factors of over 99 percent, consistent with
orders of magnitude less fluoride in most groundwater wells (< 14 mg/L) compared to leachate
at the On-site Landfill well ABP-MW023 (1,400 mg/L). This large attenuation factor supports the
efficacy of the On-site Landfill capping efforts for mitigating contaminant flux from the landfill.

This line represents dilu�on of
leachate with Badin Lake.
Samples below the dilu�on line are impacted by another
a�enua�on process.
Alcoa Badin Landfill Groundwater
MH-1
West Fill Area GroundwaterOnsite Landfill
Main Plant Groundwater
Li�le Mountain Creek Surface Water
Old Brick Landfill Groundwater
Badin Lake Surface Water
TP-1 and TP-2
TCE AreaPine Grove Area
Calculated mixtures of leachate (ABP-MW023) and Badin Lake (ABP-
SW001)
X
90%
Leachate (ABP-MW023)
Badin Lake (ABP-SW001)
80%70%60%50%40%30%20%
10%
1%
0.1%
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Figure 5-2 Comparison of Groundwater Data and Calculated Dilution Line
5.3 Validation of Groundwater-Surface Water Mixing
To verify that mixing between lake and groundwater is occurring, ion ratios were utilized as tracers of
different water types (Figure 5-3). The results show that there are distinct ion ratios for surface water
(Badin Lake and Little Mountain Creek), groundwater, and landfill leachate at the former Main Plant.
Groundwater samples fall on a mixing between these two endmembers (Figure 5-3). At the ABL,
upgradient and downgradient groundwater samples are distinct from ABL leachate (represented by ABL-
PZ17) and no mixing is apparent, consistent with fluoride observed below criteria in perimeter wells and
effective management of leachate in that location (Figure 5-4 – Graph A). At the West Fill area,
groundwater samples are intermediate between leachate represented by ABP-MW029 and background
groundwater represented by ABP-MW218, consistent with mixing between water types (Figure 5-4 –
Graph B). Also, the composition of stormwater within the storm drain (sample MH-1 from MH-2.320) is
consistent with primarily groundwater being present in the drain at the time of sampling (Figure 5-4 –
Graph B). In summary, ion ratios support the following:
• The composition of water in shoreline wells ABP-MW203, ABPMW-204, ABP-MW-205, and ABP-
BF008 are comparable to Badin Lake surface water, consistent with the groundwater elevation
data that indicate the lake is replenishing groundwater in these locations.
• The composition of shoreline wells ABP-MW016, ABP-MW110, ABP-MW111, ABP-MW112, and
ABP-MW201 at the Pine Tree Grove area and to the north fall on a mixing line, indicating
groundwater and lake water are mixing at these locations.
• Groundwater in wells around the ABL do not fall on a mixing line with leachate, indicating the
capture system is effective at containing ABL leachate.
• The West Fill area is a source of impacts to groundwater; however, concentrations are
attenuated downgradient through mixing with clean groundwater.
• Results for the OBL (not shown) fall within the range of groundwater at other locations;
however, direct comparison is not warranted as soils and rocks at this location are sourced from
basaltic rocks (as opposed to more felsic lithologies at the former Main Plant and ABL).
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Figure 5-3 Mixing Model for Former Main Plant

Figure 5-4 Mixing Model for ABL and West Fill Area
On-Site Landfill Leachate
Surface Water(Badin Lake)Represents clean recharge
MH-1Onsite Landfill, TCE Area, and Pine Grove Area
Main Plant Groundwater
Badin Lake Surface Water TP-1 and TP-2
ABLLeachate
Surface Water (Li�le Mountain Creek) Represents Clean Recharge
Most ABL samples plot near surface
water, not leachate
West Fill Leachate
Surface Water (Badin Lake) Represents Clean Recharge
A B
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5.4 Fluoride Attenuation Mechanisms
Geochemical models were completed and compared to Facility groundwater data; details of the
assessment are provided in Appendix G. Results identify that fluorite is the most likely mineral phase to
form during mixing of leachate with other water types.
Figure 5-5 shows the results of a non-conservative mixing model (i.e., minerals are allowed to
precipitate in the model) between landfill leachate (ABP-MW023) and Badin Lake water (ABP-SW001).
Whereas Badin Lake surface water is used in the model, Figure 5-3 and Figure 5-4 indicate Badin Lake
surface water is a useful proxy for background groundwater in PWR due to the similarity with
groundwater at upgradient locations ABP-MW011, ABP-MW013, ABP-MW218, and ABL-MW211.
As indicated on Figure 5-5 (Graph A), leachate in the On-site Landfill is limited in calcium, and fluorite
generally cannot form until about 5 percent mixing occurs. At the conditions within the landfill, other
calcium mineral phases are likely more stable at the high pH and low calcium conditions 5. This result
indicates that the high fluoride concentrations within landfill areas occur because a mineral buffer is not
available to control fluoride concentrations. The fact that fluoride concentrations are observed to have
declined over time in most locations (Section 4.2.1) suggests attenuation over time within the landfill
can occur, likely when calcium periodically becomes available from limited infiltration of upgradient
groundwater.
At small proportions of mixing with background groundwater (about 5 percent), sufficient calcium
becomes available for fluorite to form, and the fluoride concentration rapidly drops at the fringes of the
landfill. Fluorite continues to form and contribute to fluoride attenuation until a high degree of mixing is
achieved (over 95 percent). When the mixture reaches around 93 percent lake water, a relatively small
amount of another fluoride-bearing phase begins to form (FCO3-apatite). At high proportions of mixing
with lake water, fluoride availability becomes a limiting factor in fluorite formation because dilution is
the dominant fluoride attenuation process (Figure 5-5 – Graph B). Under these conditions, fluoride
concentrations are expected to be below criteria.

5 The zeolite leonhardite appears in the model, but at the carbon dioxide partial pressures likely in the landfill and
high pH conditions, calcium carbonate or other minerals likely serve the same role.
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Figure 5-5 Non-conservative Mixing Model Results
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6 Conclusions
Results of groundwater field measurements, laboratory analysis of COIs, and comprehensive
groundwater geochemistry measurements indicate that fluoride is the primary COI at the Facility and
concentrations are decreasing over time. Free cyanide exceeds criteria in only three groundwater wells
and is below detection limits in most wells. TCE concentrations have declined substantially since the
2000 RFI report.
Through assessment of hydraulic, constituent, and geochemistry data, the following conclusions and
refinements to the HCSM have been identified:
• Badin Lake water infiltrates into the groundwater system and provides benefits to groundwater
quality by lowering concentrations through mixing and chemical reactions that immobilize
fluoride.
o Groundwater elevations in most shoreline PWR monitoring are within error of the Badin
Lake level.
o In the Pine Tree Grove area, Badin Lake water infiltrates into fill at least as far as the rail line.
o Geochemical fingerprinting confirms lake water infiltration is occurring in this area.
• Fluoride concentrations in groundwater are stable or decreasing at almost every location since
the RFI in 1999. Current fluoride distributions are consistent with historical results,
demonstrating that the area of fluoride impacts has not increased in size.
o At the OBL, fluoride is below criteria in all wells.
o At the ABL, fluoride is only above the NC 2L standard in piezometers screened within ABL
waste materials (ABL-PZ-15 and ABL-PZ-17). Fluoride has never been detected above NC 2L
standards in any perimeter monitoring well (ABL-MW001 through ABL-MW006),
demonstrating the efficacy of the barrier wall and capture trench.
o The highest groundwater fluoride concentrations are in fill material in the On-site Landfill,
Pine Tree Grove area, West Fill area, and ABL. The fill is laterally discontinuous, so the
primary fluoride migration mechanism is when it enters the underlying and more
extensively distributed PWR.
• Hydrogeological conditions facilitate mixing between different water types and fluoride
attenuation is occurring along flow paths.
o At the On-site Landfill, the highest fluoride concentrations are in fill and there are generally
downward vertical gradients from fill to PWR, consistent with results of the RFI. Fluoride
concentrations are over an order of magnitude lower in the PWR than in the fill, indicating
vertical migration of COIs is constrained and the combination of mixing (within the more
transmissive PWR aquifer) and geochemical attenuation are causing reductions in fluoride
concentrations.
o At the toe of the On-site Landfill, upward vertical gradients are observed at the ABP-MW06A
(screened in PWR) and ABP-MW006 (screened in fill) well pairs. Upward vertical migration
of clean PWR groundwater represented by nearby wells ABP-MW-06A (fluoride = 0.26 mg/L)
and ABP-MW217 (1.4 mg/L) into fill at this location facilitates geochemical attenuation and
prevents southeastward migration of fluoride concentrations in groundwater above criteria.
o At the West Fill area, fluoride is above criteria in fill material and groundwater gradients are
downward to the PWR. Fluoride is above criteria in one central/downgradient PWR well,
indicating a pathway is present for vertical groundwater migration; however, fluoride is
below criteria in all downgradient PWR monitoring wells, indicating attenuation is occurring.
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o At the Pine Tree Grove area, fluoride is above criteria in fill wells and several PWR wells, and
groundwater gradients are downward from fill into the PWR. Groundwater elevations in
PWR closest to Badin Lake are within the margin of measurement error of the Badin Lake
stage; therefore, there is a minimal gradient to drive flux within the PWR toward Badin Lake.
This is confirmed by non-detect fluoride in Badin Lake surface water adjacent to the Pine
Tree Grove area. The horizontal groundwater gradient in fill at the Pine Tree Grove area is
away from Badin Lake at all locations, except wells ABP-MW025 and ABP-MW112, where
groundwater is likely locally perched as surrounding and more inland groundwater
elevations are lower than the lake level.
o At the ABL, groundwater gradients are downward along the north and northeast
(upgradient) edge and shift to upward about mid-way toward the downgradient edge.
Upward vertical groundwater gradients are also present furthest downgradient on the
floodplain of Little Mountain Creek. Fluoride concentrations are below criteria in wells
upgradient of the ABL, around the ABL, and downgradient of the ABL on the floodplain of
Little Mountain Creek. Fluoride is only above criteria in piezometers screened in ABL fill. This
indicates that COIs at the ABL are effectively managed by the downgradient barrier wall and
capture trench.
o Geochemical modeling indicates fluoride is attenuating.
o Ion ratios confirm mixing of different water types is occurring alone the shoreline of Badin
Lake. South of the Pine Tree Grove area, groundwater is likely directly sourced from lake
water along the shoreline. At the Pine tree Grove area and northward, groundwater is a
mixture between lake water and groundwater.
o The geochemical assessment indicates that the mineral fluorite will precipitate upon mixing
between different water types. Fluorite precipitation is a geochemical reaction that removes
fluoride from groundwater in addition to dilution that occurs from mixing of different water
types. Fluorite precipitation is identified from Facility groundwater data, which indicates
dilution alone cannot account for the magnitude of fluoride attenuation observed.
o IC and ISE Fluoride analytical methods are in agreement for samples with below about 20-30
mg/L of fluoride; therefore, the specific analytical method does not affect decisions about
compliance. Results of different fluoride analytical methods diverge at increasingly elevated
concentrations, particularly for leachate within landfills where IC methods are biased high;
therefore, modeling or fate and transport assessments that incorporate fluoride
concentrations in landfill leachate should utilize fluoride measured by the ISE method.
• Free cyanide concentrations are below criteria and are non-detect in most locations; therefore,
free cyanide is not a risk driver for groundwater at the Site.
o Free cyanide only exceeds groundwater criteria in three locations (two at the On-Site landfill
and one at the West Fill area). All locations adjacent to Badin Lake and Little Mountain Creek
were non-detect for free cyanide.
o Free cyanide was non-detect in most groundwater samples.
• TCE concentrations continue to improve in the northern area of the former Main Plant.
o TCE concentrations remain above NC 2L standards but have declined significantly since the
RFI data was collected in 1999 and 2000 and the CMS Phase 3 data was collected in 2011 in
all wells, except ABP-MW004, where concentrations fluctuate around historical ranges.
o Well ABP-MW009 has always had the highest TCE concentration at the Facility. During the
RFI TCE in groundwater was 190 µg/L. Currently, this well is 45 µg/L.
o TCE in lake shoreline well ABP-MW110 declined from 6.5 µg/L (7.1 µg/L in duplicate sample)
in July 2018 to 5.7 µg/L in June 2023, marginally above the NC 2L standard of 3 µg/L.
Hydrogeological Conceptual Site Model Validation – Badin Business Park
References
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7 References
APHA. 1992. Standard Methods for the Examination of Water and Waste Water. 4500-F- Fluoride.
ASTM, 2019. D4327-17 Standard Test Method for Anions in Water by Suppressed IC. January 28.
Baedecker, M.J. and Bach, W., 1979. Hydrogeological processes and chemical reactions at a landfill.
Groundwater, 17(5), pp.429-437.
Bethke, C.M., 2022. Geochemical and biogeochemical reaction modeling. Cambridge university press.
BHE Environmental Inc. 2006. Site Wide Storm Sewer Assessment, Alcoa Badin Facility, Badin, North
Carolina. June 2.
BHE Environmental Inc. 2011. Sitewide groundwater sampling Report, Badin Works, Badin North
Carolina. September.
EHS Support. 2022. HCSM Update – Badin Business Park. Badin, North Carolina. December.
Environeering. 2012. Phase 3 - Engineering Data Collection for the Corrective Measures Study. Badin
Works Facility, Badin, North Carolina. October 31.
USEPA. 2007. Method 9056A – Determination of Inorganic Anions by IC. Revision 1. February.
Novič, M., Lečnik, B., Hudnik, V. and Pihlar, B. 1997. Carbonate Interferences by Ion Chromatographic
Determination of Anions in Mineral Waters. Journal of Chromatography A, 764(2), pp.249-256.
State of North Carolina, 2022. Report of the Proceedings to the Environmental Management
Commission on the Proposed Changes to the Surface Water Quality Classifications and
Standards for the Protection of Surface Waters Regulations Triennial Review. 15 NCAC 02B.100-
.0300. March 10.
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Appendices

Hydrogeological Conceptual Site Model Validation – Badin Business Park

EHS Support LLC
Appendix A Data Packages and Laboratory Reports

TECHNICAL MEMORANDUM
Date: November 30, 2023
To: Mr. Jason Mibroda, Alcoa Corporation
From: Mr. Michael Worden, Civil & Environmental Consultants, Inc.
Subject: Groundwater Sampling Plan Implementation
CEC Project No.: 300-226.0025
INTRODUCTION

This Technical Memorandum (Memo) was prepared by Civil & Environmental Consultants, Inc.
(CEC) for Badin Business Park LLC (BBP), a subsidiary of Alcoa Corporation (Alcoa). This
Memo presents a summary of sampling activities (Project) conducted between May 30, 2023, and
July 19, 2023, for the BBP facility (Facility).

FACILITY BACKGROUND

The Facility, formerly known as the Alcoa-Badin Works facility, previously contained a primary
aluminum smelting plant (Main Plant). Aluminum production began at the Main Plant in 1916
after purchasing and completing the holdings of a French combine, which had begun work on a
smelter. The Main Plant consisted of potlines; electrode plants where anodes and cathodes were
manufactured; casting facilities; a machine shop; and various offices and utility buildings.
Aluminum production was curtailed in August 2002. The Main Plant continued to manufacture
anodes and high-purity aluminum until 2007 before being permanently closed in 2010. Since then,
the former Main Plant has been redeveloped into a business park for manufacturing companies.

Multiple investigations and remedial efforts have been performed at the Facility. Since the
submittal of the March 1990 Interim RCRA Facility Assessment Report, over 200 documents have
been submitted to the State of North Carolina under different regulatory programs.

On March 9, 2023, the Hydrogeological Conceptual Site Model Update (HCSM Update Report)
as prepared by EHS Support LLC and dated December 2022, was accepted by the NCDEQ. The
HCSM Update Report identified that partially weathered rock and fractured rock are contiguous
across the Facility and are the primary Main Plant-wide hydrogeologic units where groundwater
advection occurs. Sources of recharge to groundwater in the partially weathered rock and fractured
rock included precipitation infiltration and recharge from Badin Lake. Furthermore, historical
analytical data suggested that mixing between recharge water and groundwater may provide
conditions where natural, geochemical attenuation of fluoride can occur.

A comprehensive groundwater sampling event was proposed to update the understanding of
groundwater conditions and be used as a basis for verifying the findings of the HCSM Update
Report. In May 2023, a Groundwater Sampling Plan (GWSP) was prepared as a guidance
document presenting the rationale and procedures for groundwater data collection in support of
Mr. Jason Mibroda – Alcoa Corporation
CEC Project 300-226.0025
Page 2
November 30, 2023

potential refinements and/or validation to the Facility hydrogeological conceptual site model
(HCSM). The approach for the sampling was developed based on information obtained during
historical investigations and was intended to supplement previous investigations at the Facility.

SAMPLE LOCATIONS AND FREQUENCY

With the exceptions described below, groundwater samples were collected at the locations and
frequencies as detailed in the GWSP. The sampling locations were selected based on the targeted
hydrogeologic units and how well they were able to collect spatially distributed data. The first
sampling event targeted 76 wells around the Facility and included the collection of constituents of
concern and supplemental geochemical data. Selected wells were gauged for groundwater levels
prior to purging.

SUMMARY OF FIELD ACTIVITIES

On May 23 and 24, 2023, CEC field staff performed the groundwater gauging event. Depth to
water and total well depth measurements were collected from the 99 of the 100 wells identified in
the GWSP for well gauging. The remaining well, MW-35, was inadvertently missed. The nearby
well MW-34 was substituted for the missed well MW-35. Wells as part of the May 2023 gauging
event are identified on Figure 1.

Each location was gauged from the top of casing with an electronic resistivity probe. Water levels
and total depths were recorded in field notebooks along with the time and relevant notes. A copy
of the field gauging logs is provided in Attachment 1. Water level meters were decontaminated
between each measurement location following procedures outlined in the GWSP.

Between May 30, and June 14, 2023, CEC field staff performed the groundwater sampling event.
Groundwater samples were collected from 72 of the 76 wells identified in the GWSP for well
sampling. Main Plant wells MW-45 and MW-46, ABL well PZ-19, and OBL MW-1 were either
dry or did not recover sufficient groundwater for sampling. Wells as part of the May and June 2023
sampling event are identified on Figure 2.

Prior to purging, depth to water and total well depth measurements were collected from the wells
using an electronic resistivity probe. The measurements were collected before any actions were
performed that might have affected water levels. Groundwater samples were collected using a
portable (non-dedicated) pump following low-flow purging and sampling procedures outlined in
the GWSP. Dedicated tubing was used at each well to reduce the level of decontamination required
between wells and the potential for cross-contamination. Each well was purged at a relatively low
rate using a bladder pump to minimize drawdown. Well purging continued until field parameters
(i.e. pH, turbidity, specific conductance, oxidation-reduction potential, and temperature) stabilized
across three successive readings in accordance with the GWSP. If the recharge rate of the well was
less than the lowest achievable pumping rate and the well was pumped dry, a sample was collected
as soon as the water level had recovered sufficiently, even if the parameters were not stabilized. A
copy of the field sampling logs is provided in Attachment 2.
Mr. Jason Mibroda – Alcoa Corporation
CEC Project 300-226.0025
Page 3
November 30, 2023

Groundwater samples were collected directly into laboratory-prepared bottles, labeled, and placed
on ice in sealed coolers for delivery to Eurofins NSC US, Inc. in Savannah, Georgia (Eurofins
Savannah) for analysis. Reusable equipment used to collect groundwater samples were
decontaminated before use at another well. Chain-of-custody procedures were followed during
times of sampling and subsequent analysis. Removed purge water was containerized in 55-gallon
drums, labeled, and stored at a secure Facility location pending the receipt of laboratory analytical
results to determine appropriate disposal.

On July 19, 2023, CEC field staff performed a supplemental surface water sampling event. Surface
water samples were collected from three locations along Badin Lake. Surface water sampling
locations from the July 19, 2023, sampling event are identified on Figure 3.

Surface water samples were collected using a portable (non-dedicated) pump. Dedicated tubing
was used at each sampling location to reduce the level of decontamination required between
surface water sampling locations and the potential for cross-contamination. Samples were
collected directly into laboratory-prepared bottles, labeled, and placed on ice in sealed coolers for
delivery to Eurofins Savannah for analysis. Reusable equipment used to collect groundwater
samples were decontaminated before use at another well. Chain-of-custody procedures were
followed during times of sampling and subsequent analysis.

Upon receipt of the laboratory reports, CEC evaluated the data to confirm it was properly presented
without reporting errors, analyzed at the lowest reasonable dilution factors, and reported within
required or agreed upon limits of detection. A copy of the groundwater sampling laboratory reports
and completed chain-of-custody forms is provided as Attachment 3 and 5 for groundwater and
surface water respectively. Following a quality control evaluation, the laboratory analytical data
was incorporated into tables presented as Attachment 4 and 6 for groundwater and surface water
respectively.

LIMITATIONS

This memo has been prepared in keeping with accepted standards of practice for preparation of
environmental reports and using CEC's professional judgment. CEC makes no claim as to the
presence or absence of constituents except at the time of sampling and for the specific locations
and parameters sampled during the investigations. Chemical conditions may change with time.
Reported conditions may not represent current or future conditions. Chemical concentrations
between sampling points may differ. No warranties, either express or implied, are made herein.

FIGURES

DRAWN BY:DATE:APPROVED BY:PROJECT NO:FIGURE NO:1AG10/31/2023WELLS GAUGED IN MAY 2023MWWJMB300-226CHECKED BY:SCALE:P:\300-000\300-226\-GIS\Maps\300-226.0025 - GW Sampling Event\WELLS GAUGED IN MAY 2023.mxd 11/10/2023 9:36 AM (aghosh)LEGENDREFERENCEUSGS TOPOGRAPHIC MAP/ ARCGIS MAP SERVICE: HTTP://GOTO.ARCGISONLINE.COM/MAPS/USA_TOPO_MAPS, ACCESSED 11/10/2023!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!AMW-35PZ-6MW-7PZ-3MW-9MW-8MW-4MW-3BF-5BF-1MW-2MW-1PZ-5MW-46MW-28PZ-16PZ-13MW220MW218MW216MW215MW211MW210MW209MW208MW205MW204MW203MW202MW200MW-34MW-32MW-31MW-30MW-27MW-19MW-18MW-15MW-14MW-13PZ-19PZ-15MW-213MW-207MW-206MW-212PZ18RDMW-111MW-103OBL-MW-6OBL-MW-5OBL-MW-3OBL-MW-2OBL-MW-1ABL-MW-6ABL-MW-5ABL-MW-4ABL-MW-3ABL-MW-1ABL-PZ-1(S)ABL-PZ-3(S)PZ-1MW-6MW-5MW-21MW-17MW-24MW201MW-49MW-40MW-37MW-33MW-6AMW-2AMW-25MW-23MW-20MW-16MW-12MW-11MW-10PZ-17PZ-14MW-219MW-217MW-112MW-25AMW-20AMW-110MW-104ABL-MW-2OBL-MW-4ABL-PZ-2(S)ABL-PZ-1(D,I)ABL-PZ-3(D,I)ABL-PZ-2 (D,l)MW-29BF-8BF-2Source: Esri, Maxar, Earthstar Geographics, and the GIS User Community!AMonitoring Well!APiezometerBADIN BUSINESS PARK FACILITYHWY 740BADIN, NORTH CAROLINA1 " = 700 '2704 Cherokee Farm Way, Suite101 - Knoxville, TN 37920865-977-9997 865-774-7767www.cecinc.com* Hand signature on file!IIlNORTH0 350 700FeetNote: Well MW-35 was inadvertently missed during the gauging event. Well MW-34 was substituted for well MW-35.
DRAWN BY:DATE:APPROVED BY:PROJECT NO:FIGURE NO:2AG10/31/2023WELLS SAMPLED IN MAY - JUNE 2023MWWJMB300-226CHECKED BY:SCALE:P:\300-000\300-226\-GIS\Maps\300-226.0025 - GW Sampling Event\WELLS SAMPLED IN MAY - JUNE 2023.mxd 11/10/2023 8:32 AM (aghosh)LEGENDREFERENCEUSGS TOPOGRAPHIC MAP/ ARCGIS MAP SERVICE: HTTP://GOTO.ARCGISONLINE.COM/MAPS/USA_TOPO_MAPS, ACCESSED 11/10/2023!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A!AMW-9MW-8MW-4MW-3BF-5BF-1MW-2MW-1MW220MW218MW216MW215MW211MW210MW209MW208MW205MW204MW203MW202MW200MW-35MW-32MW-27MW-19MW-18MW-15MW-14MW-13PZ-15MW-212PZ18RDMW-111MW-103OBL-MW-6OBL-MW-5OBL-MW-3OBL-MW-2ABL-MW-6ABL-MW-5ABL-MW-4ABL-MW-3ABL-MW-1ABL-PZ-3(S)MW-6MW-5MW-21MW201MW-37MW-33MW-6AMW-2AMW-25MW-23MW-20MW-16MW-12MW-11MW-10PZ-17MW-217MW-112MW-25AMW-20AMW-110MW-104OBL-MW-4ABL-PZ-2(S)ABL-PZ-2 (D,l)MW-29BF-8BF-2Source: Esri, Maxar, Earthstar Geographics, and the GIS User Community!AMonitoring Well!APiezometerBADIN BUSINESS PARK FACILITYHWY 740BADIN, NORTH CAROLINA1 " = 700 '2704 Cherokee Farm Way, Suite101 - Knoxville, TN 37920865-977-9997 865-774-7767www.cecinc.com* Hand signature on file!IIlNORTH0 350 700FeetMain Plant - Central and Southern Portion Sampling LocationsOld Brick LandfillSampling LocationsMain Plant - West Fill AreaSampling LocationsAlcoa-Badin LandfillSampling LocationsMain Plant - Northwest ValleySampling Locations
!(!(!(DRAWN BY:DATE:CHECKED BY:
DWG SCALE:
APPROVED BY:
PROJECT NO:FIGURE NO:11/01/20233SURFACE WATER SAMPLED IN JULY 20230 150 300FeetSignature on File *1 " = 300 'P:\300-000\300-226\-GIS\Maps\300-226.0025 - GW Sampling Event\SURFACE WATER SAMPLING LOCATIONS.mxd - 11/10/2023 - 8:27:37 AM (aghosh)!IIlNORTH300-226SOURCE: WORLD STREET MAPARCGIS MAP SERVICE: HTTP://GOTO.ARCGISONLINE.COM/MAPS/WORLD_STREET_MAP. LAST ACCESSED: 11/10/20232704 Cherokee Farm Way, Suite101 - Knoxville, TN 37920865-977-9997 865-774-7767www.cecinc.comAGMWWJMBBADIN BUSINESS PARK FACILITYHWY 740BADIN, NORTH CAROLINA* Hand signature on fileLEGENDABP-SW001ABP-SW002ABP-SW003Surface Water Sample!(

ATTACHMENT 1
FIELD WELL GAUGING LOGS

ATTACHMENT 2
FIELD WELL SAMPLING LOGS

±5 °C ±3% ±0.2 S.U. ±20TimeVolume Purged (Gal)AppearanceTemp.( °C)Diss. Oxygen(mg/L)Sp. Cond.(µS/cm)pH(S.U.)ORP(mV)1425 NM NA 22.66 NM 104 5.62 2351430 NM NA 20.12 NM 97 5.54 2581435 NM NA 19.9 NM 98 5.51 2801440 NM NA 21.1 NM 85 5.76 2821445 NM NA 21.42 NM 93 5.68 2941448 NM NA 19.34 NM 101 5.37 3061453 NM NA 19.44 NM 101 5.38 3121456 NM NA 19.38 NM 102 5.36 3011500 NM NA 19.1 NM 102 5.34 3111504 NM NA 19.22 NM 102 5.32 3151507 NM NA 19.04 NM 101 5.31 3171510 NM NA 18.94 NM 102 5.33 3201514 NM NA 18.89 NM 102 5.3 3211517 NM NA 18.92 NM 102 5.33 323Sample ID Time Analytical Parameter NotesWell Locked?: ☐ Well Unlocked?: XSite: Badin Business Park Well #: MW-1 Total Depth (ft): 46.0BTOC?: X BGS?: ☐Measured?: X Historical?: ☐Personnel: B. Hardin Probe Type: electric Water Depth (ft): 22.89BTOC?: X BGS?: ☐ Well Material: PVC?: XWell Integrity: Good?: XDecontamination Fluids: DI water?: X Liquinox?: X Alconox?: ☐Start Time: 1425 End Time: 1520 Well Diameter (in): 2 Water Column Height (ft):X0.16 Gal/ft (2in)=Gal/Vol:Project #: 300-226 Date: 6/1/2023 Pump Type: bladder Pump Depth (ft): NMBTOC?: ☐ BGS?: ☐0.65 Gal/ft (4in)1.50 Gal/ft (6in)___ Gal/ft (___in)< 10 NTU or ±10% > 10 Other Field Measurements:Turbidity (NTU)Water Depth(BTOC)857 22.8974.5 25.25284 25.44Notes:NM - Not MeasuredNA - Not Analyzed 278 25.19135 25.284.2 25.2171.4 25.2165.1 25.2753.4 25.2545.4 25.2738.6 25.2447.3 25.2540.4 25.2437.8 25.21ABL-MW001-F1001520 Available Cyanide (1677), Fluoride (9056A), F C Fluoride WTR (4500), Br Cl SO4 (9056A), N-Nitrite (353.2), Nitrate + Nitrite (353.2), Nitrate by calc N-Nitrate, Orthophosphate (4500-FF), Silica (6010D, lab filtered), Dissolved Metals - Site List (6020B, FF), Total Carbonate + Bicarbonate alkalinity (2320B)
±5 °C ±3% ±0.2 S.U. ±20TimeVolume Purged (Gal)AppearanceTemp.( °C)Diss. Oxygen(mg/L)Sp. Cond.(µS/cm)pH(S.U.)ORP(mV)0952 0.25 cloudy 16.93 0.88 119 5.24 1570957 0.75 clearish 16.05 0.46 125 5.11 1811002 1.25 clear 16.02 0.50 96 5.01 1961007 1.75 clear 16.00 0.68 93 4.91 2131012 2.25 clear 15.89 0.82 91 4.8 2341017 2.75 clear 15.9 0.87 90 4.67 2441022 3.25 clear 15.91 0.86 89 4.59 2511027 3.75 clear 15.86 0.86 89 4.52 259Sample ID Time Analytical Parameter NotesWell Locked?: ☐ Well Unlocked?: XSite: Badin Business Park Well #: MW-3 Total Depth (ft): 15.23BTOC?: X BGS?: ☐Measured?: X Historical?: ☐Personnel: D. Cobb Probe Type: electric Water Depth (ft): ~1.1BTOC?: X BGS?: ☐ Well Material: PVC?: XWell Integrity:Good?: X Decontamination Fluids: DI water?: X Liquinox?: X Alconox?: ☐Start Time: 0947 End Time: 1145 Well Diameter (in): 2 Water Column Height (ft):X0.16 Gal/ft (2in)=Gal/Vol:Project #: 300-226 Date: 6/1/23 Pump Type: bladder Pump Depth (ft): 12.00BTOC?: X BGS?: ☐0.65 Gal/ft (4in)1.50 Gal/ft (6in)___ Gal/ft (___in)< 10 NTU or ±10% > 10 Other Field Measurements:Turbidity (NTU)Water Depth(BTOC)<1000 NM97.5 NM51.7 NMNotes:NM - Not Measured22.2 NM10.4 NM8.7 NM6.1 NM4.0 NMABL-MW003-F1001145 Available Cyanide (1677), Fluoride (9056A), F C Fluoride WTR (4500), Br Cl SO4 (9056A), N-Nitrite (353.2), Nitrate + Nitrite (353.2), Nitrate by calc N-Nitrate, Orthophosphate (4500), Total hardness (2340C), Total metals (Site list, 6020B), Total metals (RCRA, 6020B), Total Mercury (14070A), Dissolved metals (RCRA, FF, 6020B), Dissolved Hg (FF, 7470A), Total Carbonate + Bicarbonate alkalinity (2320B) H+ (4500), Dissolved Organic Carbon (FF, 5310B), TSS (2540D), Total CyanideMS + MSD collected1115 1136
±5 °C ±3% ±0.2 S.U. ±20TimeVolume Purged (Gal)AppearanceTemp.( °C)Diss. Oxygen(mg/L)Sp. Cond.(µS/cm)pH(S.U.)ORP(mV)1555 1 clear 15.33 NM 407 6.33 1931600 NM clear 15.34 NM 400 6.35 2771605 2.5 clear 15.26 NM 400 6.35 2771608 NM clear 15.25 NM 401 6.35 2611611 NM clear 15.2 NM 404 6.34 2121614 NM clear 15.17 NM 407 6.33 1671617 NM clear 15.14 NM 410 6.33 1341620 NM clear 15.1 NM 411 6.32 1141623 NM clear 15.06 NM 413 6.32 1131626 5 clear 15.04 NM 414 6.33 114Sample ID Time Analytical Parameter NotesWell Locked?: ☐ Well Unlocked?: XSite: Badin Business Park Well #: MW-4 Total Depth (ft): 16.18BTOC?: X BGS?: ☐Measured?: X Historical?: ☐Personnel: C. Ziegler Probe Type: electric Water Depth (ft): 4.46BTOC?: X BGS?: ☐ Well Material: PVC?: XWell Integrity: Good?: XDecontamination Fluids: DI water?: X Liquinox?: X Alconox?: ☐Start Time: 1530 End Time: 1715 Well Diameter (in): 2 Water Column Height (ft):X0.16 Gal/ft (2in)=Gal/Vol:Project #: 300-226 Date: 5/31/2023 Pump Type: bladder Pump Depth (ft): 15BTOC?: X BGS?: ☐0.65 Gal/ft (4in)1.50 Gal/ft (6in)___ Gal/ft (___in)< 10 NTU or ±10% > 10 Other Field Measurements:Turbidity (NTU)Water Depth(BTOC)32.3 NM13.5 NM10 NMNotes:NM - Not Measured9.4 NM8.8 NM7.3 NM7.5 NM6.6 NM6.1 NM5.1 NMABL-MW004-F1001630 Available Cyanide (1677), Fluoride (9056A)
±5 °C ±3% ±0.2 S.U. ±20TimeVolume Purged (Gal)AppearanceTemp.( °C)Diss. Oxygen(mg/L)Sp. Cond.(µS/cm)pH(S.U.)ORP(mV)1102 NM NA 16.17 NM 528 6.26 1921108 NM NA 16.86 NM 517 6.37 1941113 NM NA 16.52 NM 510 6.46 2281118 NM NA 17.28 NM 503 6.32 2251121 NM NA 16.56 NM 529 6.4 2261124 NM NA 16.35 NM 515 6.34 2121127 NM NA 16.29 NM 518 6.36 2071130 NM NA 16.38 NM 517 6.37 2101133 NM NA 16.42 NM 517 6.39 2061136 NM NA 16.32 NM 512 6.36 198Sample ID Time Analytical Parameter NotesWell Locked?: ☐ Well Unlocked?: XSite: Badin Business Park Well #: MW-5 Total Depth (ft): 14.18BTOC?: X BGS?: ☐Measured?: X Historical?: ☐Personnel: B. Hardin Probe Type: electric Water Depth (ft): 4.16BTOC?: X BGS?: ☐ Well Material: PVC?: XWell Integrity: Good?: XDecontamination Fluids: DI water?: X Liquinox?: X Alconox?: ☐Start Time: 1100 End Time: 1140 Well Diameter (in): 2 Water Column Height (ft):X0.16 Gal/ft (2in)=Gal/Vol:Project #: 300-226 Date: 5/31/2023 Pump Type: bladder Pump Depth (ft): NMBTOC?: ☐ BGS?: ☐0.65 Gal/ft (4in)1.50 Gal/ft (6in)___ Gal/ft (___in)< 10 NTU or ±10% > 10 Other Field Measurements:Turbidity (NTU)Water Depth(BTOC)554 4.79540 4.8211 4.8Notes:NM - Not MeasuredNA - Not Analyzed 116 4.7965 4.7546.2 4.7834.6 4.8123.5 4.7920.1 4.829.7 4.8ABL-MW005-F1001140Available Cyanide (1677), Fluoride (9056A), F C Fluoride WTR (4500), Br Cl SO4 (9056A), N-Nitrite (353.2), Nitrate + Nitrite (353.2), Nitrate by calc N-Nitrate, Orthophosphate (4500-FF), Total Hardness (2340B), Silica (6010D, lab filtered), Dissolved Metals - Site List (6020B, FF), Total Carbonate + Bicarbonate alkalinity (2320B), pH (4500 H+B), Dissolved Organic Carbon (5310B), TSS (2540D), Total Cyanide (D7511), PAHs (1668A) ABL-FD001-D100 Collected
±5 °C ±3% ±0.2 S.U. ±20TimeVolume Purged (Gal)AppearanceTemp.( °C)Diss. Oxygen(mg/L)Sp. Cond.(µS/cm)pH(S.U.)ORP(mV)1337 0.25 clear 21.72 2.77 157 5.96 2951342 0.5 clear 20.48 2.07 158 5.9 2821347 1.0 clear 20.33 1.83 158 5.91 2721352 1.5 clear 20.27 1.61 157 5.87 2671357 2.0 clear 20.29 1.28 156 5.83 2601402 2.5 clear 20.26 0.61 158 5.91 2521407 3.0 clear 20.21 0.25 161 5.88 2501412 3.5 clear 20.19 0.15 160 5.86 2521417 3.75 clear 20.23 0 155 5.82 2501422 4.0 clear 20.22 0 151 5.77 2531427 4.25 clear 20.23 0 150 5.77 254Sample ID Time Analytical Parameter NotesABL-MW006-F1001452 Available Cyanide (1677), Fluoride (9056A), F C Fluoride WTR (4500)NM0.2 NM1.2 NM2.3 NMNotes:NM - Not Measured2.0 NM3.7 NM11.2 NM9.0 NM5.5 NM2.7Other Field Measurements:Turbidity (NTU)Water Depth(BTOC)6.6 NM3.0 NM1.50 Gal/ft (6in)___ Gal/ft (___in)< 10 NTU or ±10% > 10 Well Integrity:Good?: X Decontamination Fluids: DI water?: X Liquinox?: X Alconox?: ☐Start Time: 1330 End Time: 1452 Well Diameter (in): 2 Water Column Height (ft):X0.16 Gal/ft (2in)=Gal/Vol:Project #: 300-226 Date: 6/1/23 Pump Type: bladder Pump Depth (ft): 35.0BTOC?: X BGS?: ☐0.65 Gal/ft (4in)Personnel: D. Cobb Probe Type: electric Water Depth (ft): 26.71BTOC?: X BGS?: ☐ Well Material: PVC?: XWell Locked?: ☐ Well Unlocked?: XSite: Badin Business Park Well #: MW-6 Total Depth (ft): 39.70BTOC?: X BGS?: ☐Measured?: X Historical?: ☐
±5 °C ±3% ±0.2 S.U. ±20TimeVolume Purged (Gal)AppearanceTemp.( °C)Diss. Oxygen(mg/L)Sp. Cond.(µS/cm)pH(S.U.)ORP(mV)1230 0.25 clear 20.96 9.69 88 6.10 2941235 0.75 cloudy 20.58 9.5 85 6.09 2961240 1.25 clear 20.57 9.41 84 5.91 2981245 2.0 clear 20.52 8.74 83 5.73 3081250 2.25 clear 20.52 8.44 84 5.73 3081255 2.5 clear 20.44 8.33 83 5.59 3221300 3.0 clear 20.41 8.26 83 5.65 3211305 3.5 clear 20.40 7.96 83 5.61 3231310 3.75 clear 20.39 7.93 83 5.61 3211315 4.0 clear 20.31 8.03 84 5.52 3251320 4.5 clear 20.30 8.97 84 5.41 3341323 4.75 clear 20.37 10.01 84 5.56 3431326 5.0 clear 20.41 9.51 83 5.52 335Sample ID Time Analytical Parameter NotesWell Locked?: X Well Unlocked?: ☐ABP-MW210-F1001331 Available Cyanide (1677), Fluoride (9056A), F C Fluoride WTR (4500)Site: Badin Business Park Well #: MW-210 Total Depth (ft): 32.54BTOC?: X BGS?: ☐Measured?: X Historical?: ☐Personnel: D. Cobb Probe Type: electric Water Depth (ft): 13.21BTOC?: X BGS?: ☐ Well Material: PVC?: XWell Integrity: Good?: XX0.16 Gal/ft (2in)=Gal/Vol:Project #: 300-226 Date: 5/31/23 Pump Type: bladderPump Depth (ft): 26.00BTOC?: X BGS?: ☐0.65 Gal/ft (4in)1.50 Gal/ft (6in)___ Gal/ft (___in)< 10 NTU or ±10% > 10 Other Field Measurements:Turbidity (NTU)Water Depth(BTOC)373 NM156 NMDecontamination Fluids: DI water?: X Liquinox?: X Alconox?: ☐Start Time: 1203 End Time: 1331 Well Diameter (in): 2 Water Column Height (ft):57.4 NMNotes:NM - Not Measuredbad bladder; had to replacealso replaced bottom o-ring29.1 NM14.9 NM12.9 NM9.8 NM7.8 NM8.5 NM10.1 NM7.3 NM10.9 NM6.3 NM
±5 °C ±3% ±0.2 S.U. ±20TimeVolume Purged (Gal)AppearanceTemp.( °C)Diss. Oxygen(mg/L)Sp. Cond.(µS/cm)pH(S.U.)ORP(mV)1037 0.25 clear 19.37 3.75 393 6.14 2501042 0.75 clear 19.05 3.12 355 6.75 2421047 1.25 clear 19.05 2.96 337 6.88 2461052 1.75 clear 19.07 3.38 319 6.85 2531057 2.25 clear 19.18 3.41 303 6.71 2581102 2.75 clear 19.22 3.49 293 6.59 262Sample ID Time Analytical Parameter NotesWell Locked?: ☐ Well Unlocked?: XSite: Badin Business Park Well #: MW-211 Total Depth (ft): 31.7BTOC?: X BGS?: ☐Measured?: X Historical?: ☐Personnel: D. Cobb Probe Type: electric Water Depth (ft): 17.19BTOC?: X BGS?: ☐ Well Material: PVC?: XWell Integrity: Good?: XDecontamination Fluids: DI water?: X Liquinox?: X Alconox?: ☐Start Time: 1032 End Time: 1107 Well Diameter (in): 2 Water Column Height (ft):X0.16 Gal/ft (2in)=Gal/Vol:Project #: 300-226 Date: 5/31/23 Pump Type: bladderPump Depth (ft): 26.00BTOC?: X BGS?: ☐0.65 Gal/ft (4in)1.50 Gal/ft (6in)___ Gal/ft (___in)< 10 NTU or ±10% > 10 Other Field Measurements:Turbidity (NTU)Water Depth(BTOC)20.9 NM22.2 NM17.0 NMNotes:NM - Not Measured10.5 NM5.4 NM1.2 NMABL-MW211-F1001107 Available Cyanide (1677), Fluoride (9056A), F C Fluoride WTR (4500), Br Cl SO4 (9056A), N-Nitrite (353.2), Nitrate + Nitrite (353.2), Nitrate by calc N-Nitrate, Orthophosphate (4500), Silica (6010D, lab filtered), Dissolved Metals - Site List (6020B, FF), Total Carbonate + Bicarbonate alkalinity (2320B)
±5 °C ±3% ±0.2 S.U. ±20TimeVolume Purged (Gal)AppearanceTemp.( °C)Diss. Oxygen(mg/L)Sp. Cond.(µS/cm)pH(S.U.)ORP(mV)1438 0.25 clear 20.51 5.14 282 5.98 1901443 0.5 clear 20.43 4.76 281 6.16 1901448 1 clear 20.39 4.39 287 6.48 1841453 1.5 clear 20.39 4.26 277 6.59 1861458 2 clear 20.51 3.97 191 6.44 1891503 2.5 clear 20.61 3.76 252 6.45 1901508 3 clear 20.67 3.71 240 6.35 1561513 3.5 clear 20.78 3.33 231 6.02 2071518 3.75 cloudy 20.85 3.86 224 5.8 2231523 4 clear 20.8 3.91 218 5.94 2141528 4.25 clear 20.77 3.78 211 5.89 2191538 5.0 clear 20.63 3.45 211 6.06 2171543 5.5 clear 20.64 3.27 209 5.83 226Sample ID Time Analytical Parameter NotesABL-MW212-F1001548 Free Cyanide (1677), Fluoride (9056A), F C Fluoride WTR (4500), Br Cl SO4 (9056A), N-Nitrite (353.2), Nitrate + Nitrite (353.2), Nitrate by calc N-Nitrate, Orthophosphate (4500-FF), Silica (6010D, lab filtered), Dissolved Metals - Site List (6020B, FF), Total Carbonate + Bicarbonate alkalinity (2320B)7.4 NMNM9.9 NM29.6 NM18.9 NMNotes:NM - Not Measuredmissed 1533 reading due to rainspent time covering equipment31.3 NM37.7 NM38.1 NM44.7 NM46.8 NM38.2 NM25.4Other Field Measurements:Turbidity (NTU)Water Depth(BTOC)13.5 NM16.1 NM1.50 Gal/ft (6in)___ Gal/ft (___in)< 10 NTU or ±10% > 10 Well Integrity: Good?: XDecontamination Fluids: DI water?: X Liquinox?: X Alconox?: ☐Start Time: 1438 End Time: 1548 Well Diameter (in): 2 Water Column Height (ft):X0.16 Gal/ft (2in)=Gal/Vol:Project #: 300-226 Date: 5/30/23 Pump Type: bladderPump Depth (ft): 26.00BTOC?: X BGS?: ☐0.65 Gal/ft (4in)Personnel: D. Cobb Probe Type: electric Water Depth (ft): 16.11BTOC?: X BGS?: ☐ Well Material: PVC?: XWell Locked?: ☐ Well Unlocked?: XSite: Badin Business Park Well #: MW-212 Total Depth (ft): 36.37BTOC?: X BGS?: ☐Measured?: X Historical?: ☐
±5 °C ±3% ±0.2 S.U. ±20TimeVolume Purged (Gal)AppearanceTemp.( °C)Diss. Oxygen(mg/L)Sp. Cond.(µS/cm)pH(S.U.)ORP(mV)1500 NM clear 17.18 NM 92 5.74 1721503 NM clear 17.2 NM 93 5.74 1691506 4.5 clear 17.21 NM 92 5.74 166Sample ID Time Analytical Parameter NotesWell Locked?: ☐ Well Unlocked?: XSite: Badin Business Park Well #: MW-215 Total Depth (ft): 40.00BTOC?: X BGS?: ☐Measured?: X Historical?: ☐Personnel: C. Ziegler Probe Type: electric Water Depth (ft): 23.00BTOC?: X BGS?: ☐ Well Material: PVC?: XWell Integrity: Good?: XDecontamination Fluids: DI water?: X Liquinox?: X Alconox?: ☐Start Time: 1430 End Time: 1506 Well Diameter (in): 2Water Column Height (ft):X0.16 Gal/ft (2in)=Gal/Vol:Project #: 300-226 Date: 5/30/2023 Pump Type: bladder Pump Depth (ft): 37.5BTOC?: X BGS?: ☐0.65 Gal/ft (4in)1.50 Gal/ft (6in)___ Gal/ft (___in)< 10 NTU or ±10% > 10 Other Field Measurements:Turbidity (NTU)Water Depth(BTOC)7.7 NM8.9 NM10 NMNotes:NM - Not MeasuredABL-MW215-F1001506Available Cyanide (1677), Fluoride (9056A), F C Fluoride WTR (4500), Br Cl SO4 (9056A), N-Nitrite (353.2), Nitrate + Nitrite (353.2), Nitrate by calc N-Nitrate, Orthophosphate (4500-FF), Total Hardness (2340B), Silica (6010D, lab filtered), Dissolved Metals - Site List (6020B, FF), Total Carbonate + Bicarbonate alkalinity (2320B), pH (4500 H+B), Dissolved Organic Carbon (5310B), TSS (2540D), Total Cyanide (D7511), PAHs (1668A)
±5 °C ±3% ±0.2 S.U. ±20TimeVolume Purged (Gal)AppearanceTemp.( °C)Diss. Oxygen(mg/L)Sp. Cond.(µS/cm)pH(S.U.)ORP(mV)1503 NM NA 21.38 NM 194 5.15 2411508 NM NA 21.38 NM 191 5.17 2361511 NM NA 21.3 NM 191 5.19 2271516 NM NA 21.65 NM 184 5.13 2241521 NM NA 21.61 NM 184 5.17 232Sample ID Time Analytical Parameter NotesWell Locked?: ☐ Well Unlocked?: XSite: Badin Business Park Well #: MW-216 Total Depth (ft): 62.40BTOC?: X BGS?: ☐Measured?: X Historical?: ☐Personnel: B. Hardin Probe Type: electric Water Depth (ft): 44.24BTOC?: X BGS?: ☐ Well Material: PVC?: XWell Integrity: Good?: XDecontamination Fluids: DI water?: X Liquinox?: X Alconox?: ☐Start Time: 1503 End Time: 1523 Well Diameter (in): 2 Water Column Height (ft):X0.16 Gal/ft (2in)=Gal/Vol:Project #: 300-226 Date: 5/30/2023 Pump Type: bladder Pump Depth (ft): NMBTOC?: ☐ BGS?: ☐0.65 Gal/ft (4in)1.50 Gal/ft (6in)___ Gal/ft (___in)< 10 NTU or ±10% > 10 Other Field Measurements:Turbidity (NTU)Water Depth(BTOC)NM 44.24NM 44.31NM 44.32Notes:NM - Not MeasuredNA - Not Analyzed NM 44.50NM 44.39ABL-MW216-F1001523 Available Cyanide (1677), Fluoride (9056A), F C Fluoride WTR (4500), Br Cl SO4 (9056A), N-Nitrite (353.2), Nitrate + Nitrite (353.2), Nitrate by calc N-Nitrate, Orthophosphate (4500-FF), Silica (6010D, lab filtered), Dissolved Metals - Site List (6020B, FF), Total Carbonate + Bicarbonate alkalinity (2320B)Turbidity Sensor Malfunctioned
±5 °C ±3% ±0.2 S.U. ±20TimeVolume Purged (Gal)AppearanceTemp.( °C)Diss. Oxygen(mg/L)Sp. Cond.(µS/cm)pH(S.U.)ORP(mV)1028 NM NA 21.56 NM 219 5.83 411033 NM NA 18.85 NM 187 6.14 461038 NM NA 19.39 NM 193 6.14 511043 NM NA 19.19 NM 203 6.17 251055 NM NA 20.6 NM 205 6.26 -251058 NM NA 20.27 NM 179 6.2 -61101 NM NA 19.35 NM 177 6.16 -111106 NM NA 19.69 NM 176 6.18 -11109 NM NA 20.07 NM 174 6.16 -5Sample ID Time Analytical Parameter NotesWell Locked?: ☐ Well Unlocked?: XSite: Badin Business Park Well #: PZ-2S Total Depth (ft): 46.68BTOC?: X BGS?: ☐Measured?: X Historical?: ☐Personnel: B. Hardin Probe Type: electric Water Depth (ft): 41.06BTOC?: X BGS?: ☐ Well Material: PVC?: XWell Integrity: Good?: XDecontamination Fluids: DI water?: X Liquinox?: X Alconox?: ☐Start Time: 1028 End Time: 1115 Well Diameter (in): 1 Water Column Height (ft):X0.16 Gal/ft (2in)=Gal/Vol:Project #: 300-226 Date: 6/1/2023 Pump Type: bladderPump Depth (ft): NMBTOC?: ☐ BGS?: ☐0.65 Gal/ft (4in)1.50 Gal/ft (6in)___ Gal/ft (___in)< 10 NTU or ±10% > 10 Other Field Measurements:Turbidity (NTU)Water Depth(BTOC)580 41.32289 41.78105 42.02Notes:NM - Not MeasuredNA - Not Analyzed 32.6 42.1514.8 91.8327.7 41.9825.9 42.0822.2 42.157.6 42.23ABL-PZ02S-F1001115 Available Cyanide (1677), Fluoride (9056A) ABL-FD002-D100 Collected
±5 °C ±3% ±0.2 S.U. ±20TimeVolume Purged (Gal)AppearanceTemp.( °C)Diss. Oxygen(mg/L)Sp. Cond.(µS/cm)pH(S.U.)ORP(mV)1152 NM NA 21.29 4.56 121 6.12 1421200 NM NA 21.9 2.74 107 6.21 2311208 NM NA 22.91 4.48 109 5.79 3341211 NM NA 21.53 NM 106 5.76 3511216 NM NA 21.22 NM 108 5.84 3311246 NM NA 26.74 NM 111 5.87 3331251 NM NA 24.46 NM 107 5.86 3381257 NM NA 24.18 NM 107 5.68 336Sample ID Time Analytical Parameter NotesWell Locked?: ☐ Well Unlocked?: XSite: Badin Business Park Well #: PZ-2D Total Depth (ft): 78.80BTOC?: X BGS?: ☐Measured?: X Historical?: ☐Personnel: B. Hardin Probe Type: electric Water Depth (ft): 47.93BTOC?: X BGS?: ☐ Well Material: PVC?: XWell Integrity: Good?: XDecontamination Fluids: DI water?: X Liquinox?: X Alconox?: ☐Start Time: 1152 End Time: 1300 Well Diameter (in): 1 Water Column Height (ft):X0.16 Gal/ft (2in)=Gal/Vol:Project #: 300-226 Date: 6/1/2023 Pump Type: bladderPump Depth (ft): NMBTOC?: ☐ BGS?: ☐0.65 Gal/ft (4in)1.50 Gal/ft (6in)___ Gal/ft (___in)< 10 NTU or ±10% > 10 Other Field Measurements:Turbidity (NTU)Water Depth(BTOC)19 48.123 48.451.3 48.35Notes:NM - Not MeasuredNA - Not Analyzed 0.9 48.41.8 48.524.8 48.3111.3 48.356 48.41ABL-PZ02D-F1001300 Available Cyanide (1677), Fluoride (9056A)
±5 °C ±3% ±0.2 S.U. ±20TimeVolume Purged (Gal)AppearanceTemp.( °C)Diss. Oxygen(mg/L)Sp. Cond.(µS/cm)pH(S.U.)ORP(mV)1155 1 clear 15.62 NM 431 6.05 281200 NM clear 16.04 NM 443 6.20 711205 1.5 clear 16.35 NM 453 6.38 65Sample ID Time Analytical Parameter NotesWell Locked?: ☐ Well Unlocked?: XSite: Badin Business Park Well #: PZ-3S Total Depth (ft): 10.94BTOC?: X BGS?: ☐Measured?: X Historical?: ☐Personnel: C. Ziegler Probe Type: electric Water Depth (ft): 5.80BTOC?: X BGS?: ☐ Well Material: PVC?: XWell Integrity: Good?: XDecontamination Fluids: DI water?: X Liquinox?: X Alconox?: ☐Start Time: 1100 End Time: 1430 Well Diameter (in): 1 Water Column Height (ft):X0.16 Gal/ft (2in)=Gal/Vol:Project #: 300-226 Date: 5/31/2023 Pump Type: bladder Pump Depth (ft): 8.5BTOC?: X BGS?: ☐0.65 Gal/ft (4in)1.50 Gal/ft (6in)___ Gal/ft (___in)< 10 NTU or ±10% > 10 Other Field Measurements:Turbidity (NTU)Water Depth(BTOC)10.9 NM11.4 NM11.1 NMNotes:NM - Not Measured1207 - Purged Dry, allowed to recharge for 20 minutes1230 - Pump set to 6" from well bottom to sample ABL-PZ03S-F1001230Available Cyanide (1677), Fluoride (9056A), F C Fluoride WTR (4500), Br Cl SO4 (9056A), N-Nitrite (353.2), Nitrate + Nitrite (353.2), Nitrate by calc N-Nitrate, Orthophosphate (4500-FF), Total Hardness (2340B), Silica (6010D, lab filtered), Dissolved Metals - Site List (6020B, FF), Total Carbonate + Bicarbonate alkalinity (2320B), pH (4500 H+B), Dissolved Organic Carbon (5310B), TSS (2540D), Total Cyanide (D7511), PAHs (1668A)
±5 °C ±3% ±0.2 S.U. ±20TimeVolume Purged (Gal)AppearanceTemp.( °C)Diss. Oxygen(mg/L)Sp. Cond.(µS/cm)pH(S.U.)ORP(mV)1025 0.5 clear 20.77 NM 2630 7.12 -851028 NM NA 20.92 NM 2640 7.12 -821031 NM NA 21.31 NM 2620 7.12 -771034 0.75 NA 21.57 NM 2630 7.12 -73Sample ID Time Analytical Parameter NotesABL-PZ015-F1001035 Available Cyanide (1677), Fluoride (9056A)49 NMNotes:NM - Not MeasuredNA- Not Analyzed 51 NMOther Field Measurements:Turbidity (NTU)Water Depth(BTOC)63.1 NM48.3 NM1.50 Gal/ft (6in)___ Gal/ft (___in)< 10 NTU or ±10% > 10 Well Integrity: Good?: XDecontamination Fluids: DI water?: X Liquinox?: X Alconox?: ☐Start Time: 930 End Time: 1220 Well Diameter (in): 1Water Column Height (ft):X0.16 Gal/ft (2in)=Gal/Vol:Project #: 300-226 Date: 6/1/2023 Pump Type: bladderPump Depth (ft): 39BTOC?: X BGS?: ☐0.65 Gal/ft (4in)Personnel: C. Ziegler Probe Type: electric Water Depth (ft): 36.41BTOC?: X BGS?: ☐ Well Material: PVC?: XWell Locked?: ☐ Well Unlocked?: XSite: Badin Business Park Well #: PZ-15 Total Depth (ft): 39.90BTOC?: X BGS?: ☐Measured?: X Historical?: ☐
±5 °C ±3% ±0.2 S.U. ±20TimeVolume Purged (Gal)AppearanceTemp.( °C)Diss. Oxygen(mg/L)Sp. Cond.(µS/cm)pH(S.U.)ORP(mV)1305 <0.25 NA 26.66 NM 2240 7.39 -94Sample ID Time Analytical Parameter NotesABL-PZ017-F1001620 Available Cyanide (1677), Fluoride (9056A), F C Fluoride WTR (4500), Br Cl SO4 (9056A), N-Nitrite (353.2), Nitrate + Nitrite (353.2), Nitrate by calc N-Nitrate, Orthophosphate (4500-FF), Silica (6010D, lab filtered), Dissolved Metals - Site List (6020B, FF), Total Carbonate + Bicarbonate alkalinity (2320B)Notes:NM - Not MeasuredNA - Not Analyzed Pumped dry at 1308Sampled collected over extended period of time due to very slow production at 1620Other Field Measurements:Turbidity (NTU)Water Depth(BTOC)126 NM1.50 Gal/ft (6in)___ Gal/ft (___in)< 10 NTU or ±10% > 10 Well Integrity: Good?: XDecontamination Fluids: DI water?: X Liquinox?: X Alconox?: ☐Start Time: 1230 End Time: 1620 Well Diameter (in): 1 Water Column Height (ft):X0.16 Gal/ft (2in)=Gal/Vol:Project #: 300-226 Date: 6/1/2023 Pump Type: bladderPump Depth (ft): 36BTOC?: X BGS?: ☐0.65 Gal/ft (4in)Personnel: C. Ziegler Probe Type: electric Water Depth (ft): 31.88BTOC?: X BGS?: ☐ Well Material: PVC?: XWell Locked?: ☐ Well Unlocked?: XSite: Badin Business Park Well #: PZ-17 Total Depth (ft): 36.80BTOC?: X BGS?: ☐Measured?: X Historical?: ☐
±5 °C ±3% ±0.2 S.U. ±20TimeVolume Purged (Gal)AppearanceTemp.( °C)Diss. Oxygen(mg/L)Sp. Cond.(µS/cm)pH(S.U.)ORP(mV)1418 NM NA 20.11 NM 3.63 6.68 1771423 NM NA 19.97 NM 581 6.55 2341428 NM NA 19.22 NM 583 6.57 2471431 NM NA 18.97 NM 588 6.57 2551434 NM NA 18.99 NM 587 6.55 2581437 NM NA 18.88 NM 584 6.46 2631440 NM NA 18.92 NM 586 6.5 2601443 NM NA 19.03 NM 593 6.53 2621448 NM NA 19.19 NM 589 6.51 2681453 NM NA 18.99 NM 585 6.57 2581458 NM NA 18.81 NM 584 6.58 2631503 NM NA 18.59 NM 586 6.49 2711503 NM NA 18.92 NM 586 6.46 2731511 NM NA 19.13 NM 592 6.38 2691516 NM NA 18.87 NM 587 6.43 268Sample ID Time Analytical Parameter NotesABL-PZ18RD-F1001530 Available Cyanide (1677), Fluoride (9056A), F C Fluoride WTR (4500), Br Cl SO4 (9056A), N-Nitrite (353.2), Nitrate + Nitrite (353.2), Nitrate by calc N-Nitrate, Orthophosphate (4500-FF), Silica (6010D, lab filtered), Dissolved Metals - Site List (6020B, FF), Total Carbonate + Bicarbonate alkalinity (2320B)71.3 9.9975.2 1077.3 10.019.9586.3 9.94122 9.95508 10.03Notes:NM - Not MeasuredNA - Not Analyzed 388 9.98325 10.01278 10.09243 10.08195 10153 9.97115Other Field Measurements:Turbidity (NTU)Water Depth(BTOC)641 10.25794 10.041.50 Gal/ft (6in)___ Gal/ft (___in)< 10 NTU or ±10% > 10 Well Integrity: Good?: XDecontamination Fluids: DI water?: X Liquinox?: X Alconox?: ☐Start Time: 1418 End Time: 1530 Well Diameter (in): 1 Water Column Height (ft):X0.16 Gal/ft (2in)=Gal/Vol:Project #: 300-226 Date: 5/31/2023 Pump Type: bladder Pump Depth (ft): NMBTOC?: ☐ BGS?: ☐0.65 Gal/ft (4in)Personnel: B. Hardin Probe Type: electric Water Depth (ft): 9.58BTOC?: X BGS?: ☐ Well Material: PVC?: XWell Locked?: ☐ Well Unlocked?: XSite: Badin Business Park Well #: PZ-18RD Total Depth (ft): 38.45BTOC?: X BGS?: ☐Measured?: X Historical?: ☐
±5 °C ±3% ±0.2 S.U. ±20TimeVolume Purged (Gal)AppearanceTemp.( °C)Diss. Oxygen(mg/L)Sp. Cond.(µS/cm)pH(S.U.)ORP(mV)Sample ID Time Analytical Parameter NotesNotes:Not samped - Pumped dryOther Field Measurements:Turbidity (NTU)Water Depth(BTOC)1.50 Gal/ft (6in)___ Gal/ft (___in)< 10 NTU or ±10% > 10 Well Integrity: Good?: XDecontamination Fluids: DI water?: X Liquinox?: X Alconox?: ☐Start Time: 930 End Time: NA Well Diameter (in): 1 Water Column Height (ft):X0.16 Gal/ft (2in)=Gal/Vol:Project #: 300-226 Date: 6/2/2023 Pump Type: bladderPump Depth (ft): 17.3BTOC?: X BGS?: ☐0.65 Gal/ft (4in)Personnel: C. Ziegler Probe Type: electric Water Depth (ft): 14.06BTOC?: X BGS?: ☐ Well Material: PVC?: XWell Locked?: ☐ Well Unlocked?: XSite: Badin Business Park Well #: PZ-19 Total Depth (ft): 17.87BTOC?: X BGS?: ☐Measured?: X Historical?: ☐
±5 °C ±3% ±0.2 S.U. ±20TimeVolume Purged (Gal)AppearanceTemp.( °C)Diss. Oxygen(mg/L)Sp. Cond.(µS/cm)pH(S.U.)ORP(mV)1619 NM NA 26.22 NM 146 5.86 3481624 NM NA 23.1 NM 147 5.52 3651629 NM NA 19.65 NM 149 5.65 3631632 NM NA 19.17 NM 150 5.71 3671635 NM NA 19.12 NM 152 5.73 373Sample ID Time Analytical Parameter NotesWell Locked?: ☐ Well Unlocked?: XSite: Badin Business Park Well #: MW-1 Total Depth (ft): 34.94BTOC?: X BGS?: ☐Measured?: X Historical?: ☐Personnel: B. Hardin Probe Type: electric Water Depth (ft): 25.17BTOC?: X BGS?: ☐ Well Material: PVC?: XWell Integrity: Good?: XDecontamination Fluids: DI water?: X Liquinox?: X Alconox?: ☐Start Time: 1619 End Time: 1640 Well Diameter (in): 2 Water Column Height (ft):X0.16 Gal/ft (2in)=Gal/Vol:Project #: 300-226 Date: 6/6/2023 Pump Type: bladder Pump Depth (ft): NMBTOC?: ☐ BGS?: ☐0.65 Gal/ft (4in)1.50 Gal/ft (6in)___ Gal/ft (___in)< 10 NTU or ±10% > 10 Other Field Measurements:Turbidity (NTU)Water Depth(BTOC)65.6 25.4227.2 25.4816.5 25.62Notes:NM - Not MeasuredNA - Not Analyzed 11.2 25.668.7 25.71ABP-MW001-F1001640 Available Cyanide (1677), Fluoride (9056A)
±5 °C ±3% ±0.2 S.U. ±20TimeVolume Purged (Gal)AppearanceTemp.( °C)Diss. Oxygen(mg/L)Sp. Cond.(µS/cm)pH(S.U.)ORP(mV)905 0.5 Brown 18.77 NM 1700 6.22 197910 NM Brown 18.74 NM 1720 6.20 191915 NM Brown 18.78 NM 1840 6.27 183920 NM Brown 18.82 NM 2000 6.33 187925 NM Clearer 18.69 NM 2120 6.40 196930 NM Yellowish 18.59 NM 2120 6.43 197935 NM Yellowish 18.63 NM 2280 6.52 197938 NM Yellowish 18.58 NM 2340 6.54 196941 4.25 Yellowish 18.67 NM 2350 6.55 195Sample ID Time Analytical Parameter NotesABP-MW002-F100945 Available Cyanide (1677), Fluoride (9056A)54.9 NMNotes:NM - Not Measured62.8 NM33.1 NM14.7 NM9.9 NM7.8 NM6.3 NMOther Field Measurements:Turbidity (NTU)Water Depth(BTOC)109 NM53.2 NM1.50 Gal/ft (6in)___ Gal/ft (___in)< 10 NTU or ±10% > 10 Well Integrity: FM. Bolts don't tighten Good?: XDecontamination Fluids: DI water?: X Liquinox?: X Alconox?: ☐Start Time: 820 End Time: 1020 Well Diameter (in): 2 Water Column Height (ft):X0.16 Gal/ft (2in)=Gal/Vol:Project #: 300-226 Date: 6/8/2023 Pump Type: bladderPump Depth (ft): 21BTOC?: X BGS?: ☐0.65 Gal/ft (4in)Personnel: C. Ziegler Probe Type: electric Water Depth (ft): 17.10BTOC?: X BGS?: ☐ Well Material: PVC?: XWell Locked?: ☐ Well Unlocked?: XSite: Badin Business Park Well #: MW-2 Total Depth (ft): 24.25BTOC?: X BGS?: ☐Measured?: X Historical?: ☐
±5 °C ±3% ±0.2 S.U. ±20TimeVolume Purged (Gal)AppearanceTemp.( °C)Diss. Oxygen(mg/L)Sp. Cond.(µS/cm)pH(S.U.)ORP(mV)1105 2.5 Brown 19.25 NM 506 6.67 -1051110 NM Brown 19.29 NM 511 6.69 -1131115 NM Clearer 19.26 NM 514 6.71 -1111120 NM Clearer 19.15 NM 520 6.69 -1171125 NM Clearer 19.06 NM 523 6.7 -1191128 5 Clearer 19.11 NM 522 6.68 -119Sample ID Time Analytical Parameter NotesABP-MW02A-F1001130 Available Cyanide (1677), Fluoride (9056A), F C Fluoride WTR (4500), Br Cl SO4 (9056A), N-Nitrite (353.2), Nitrate + Nitrite (353.2), Nitrate by calc N-Nitrate, Orthophosphate (4500), Total Carbonate + Bicarbonate alkalinity (2320B), Silica (6010D), Dissolved Metals - Site List (6020B-FF), Dissolved organic carbon (5310 B-FF), TSS (2540D)46.2 NMNotes:NM - Not Measured30.2 NM29.3 NM27.2 NMOther Field Measurements:Turbidity (NTU)Water Depth(BTOC)70.6 NM55 NM1.50 Gal/ft (6in)___ Gal/ft (___in)< 10 NTU or ±10% > 10 Well Integrity: FM. 2/3 bolts missing, last doesn't screwDecontamination Fluids: DI water?: X Liquinox?: X Alconox?: ☐Start Time: 1020 End Time: 1215 Well Diameter (in): 2 Water Column Height (ft):X0.16 Gal/ft (2in)=Gal/Vol:Project #: 300-226 Date: 6/8/2023 Pump Type: bladder Pump Depth (ft): 40BTOC?: X BGS?: ☐0.65 Gal/ft (4in)Personnel: C. Ziegler Probe Type: electric Water Depth (ft): 18.85BTOC?: X BGS?: ☐ Well Material: PVC?: XWell Locked?: ☐ Well Unlocked?: XSite: Badin Business Park Well #: MW-2A Total Depth (ft): 47.02BTOC?: X BGS?: ☐Measured?: X Historical?: ☐
±5 °C ±3% ±0.2 S.U. ±20TimeVolume Purged (Gal)AppearanceTemp.( °C)Diss. Oxygen(mg/L)Sp. Cond.(µS/cm)pH(S.U.)ORP(mV)1525 0.25 clear 20.66 1.06 278 6.75 2791530 0.75 clear 19.91 0.00 280 6.69 2741535 1.0 clear 19.66 0.00 286 6.69 2681540 1.25 clear 19.21 0.00 287 6.66 2551545 1.5 clear 19.27 0.00 287 6.64 2351550 1.75 clear 19.30 0.00 289 6.66 1971555 2.0 clear 19.24 0.00 289 6.65 1311600 2.10 clear 19.66 0.00 288 6.65 1071603 2.20 clear 19.82 0.00 288 6.64 1001606 2.30 clear 19.87 0.00 288 6.66 98Sample ID Time Analytical Parameter NotesABP-MW003-F1001611 Available Cyanide (1677), Fluoride (9056A), F C Fluoride WTR (4500)NM0.0 NM2.9 NMNotes:NM - Not Measured1.0 NM1.3 NM0.7 NM0.0 NM0.0 NM0.0Other Field Measurements:Turbidity (NTU)Water Depth(BTOC)7.6 NM4.8 NM1.50 Gal/ft (6in)___ Gal/ft (___in)< 10 NTU or ±10% > 10 Well Integrity:Good?: X Decontamination Fluids: DI water?: X Liquinox?: X Alconox?: ☐Start Time: 1520 End Time: 1611 Well Diameter (in): 2 Water Column Height (ft):X0.16 Gal/ft (2in)=Gal/Vol:Project #: 300-226 Date: 6/8/23 Pump Type: bladder Pump Depth (ft): 25.00BTOC?: X BGS?: ☐0.65 Gal/ft (4in)Personnel: D. Cobb Probe Type: electric Water Depth (ft): 14.60BTOC?: X BGS?: ☐ Well Material: PVC?: XWell Locked?: ☐ Well Unlocked?: XSite: Badin Business Park Well #: MW-3 Total Depth (ft): 33.91BTOC?: X BGS?: ☐Measured?: X Historical?: ☐
±5 °C ±3% ±0.2 S.U. ±20TimeVolume Purged (Gal)AppearanceTemp.( °C)Diss. Oxygen(mg/L)Sp. Cond.(µS/cm)pH(S.U.)ORP(mV)1321 NM NA 20.24 NM 715 6.89 1881326 NM NA 19.1 NM 447 6.91 1901330 NM NA 19.12 NM 516 6.97 1991336 NM NA 19.15 NM 676 7.1 2151341 NM NA 19.17 NM 796 7.14 2301346 NM NA 19.05 NM 904 7.15 2441349 NM NA 19.13 NM 985 7.17 2481352 NM NA 19.4 NM 1040 7.21 2521355 NM NA 19.17 NM 1140 7.35 2551358 NM NA 19.37 NM 1170 7.35 2551501 NM NA 19.2 NM 1150 7.32 257Sample ID Time Analytical Parameter NotesWell Locked?: ☐ Well Unlocked?: XSite: Badin Business Park Well #: MW-4 Total Depth (ft): 18.56BTOC?: X BGS?: ☐Measured?: X Historical?: ☐Personnel: B. Hardin Probe Type: electric Water Depth (ft): 11.76BTOC?: X BGS?: ☐ Well Material: PVC?: XWell Integrity: Good?: XDecontamination Fluids: DI water?: X Liquinox?: X Alconox?: ☐Start Time: 1321 End Time: 1405 Well Diameter (in): 2 Water Column Height (ft):X0.16 Gal/ft (2in)=Gal/Vol:Project #: 300-226 Date: 6/13/2023 Pump Type: bladderPump Depth (ft): NMBTOC?: ☐ BGS?: ☐0.65 Gal/ft (4in)1.50 Gal/ft (6in)___ Gal/ft (___in)< 10 NTU or ±10% > 10 Other Field Measurements:Turbidity (NTU)Water Depth(BTOC)>1000 12.18>1000 13.15694 13.45Notes:NM - Not MeasuredNA - Not Analyzed 316 13.75286 13.92282 14.18277 14.25250 14.51370 14.65370 14.82374 14.68ABP-MW0041405 Available Cyanide (1677), Fluoride (9056A), F C Fluoride WTR (4500), Br Cl SO4 (9056A), N-Nitrite (353.2), Nitrate + Nitrite (353.2), Nitrate by calc N-Nitrate, Orthophosphate (4500), Total Carbonate + Bicarbonate alkalinity (2320B), Silica (6010D), Dissolved Metals - Site List (6020B-FF), Dissolved organic carbon (5310 B-FF), TSS (2540D), VOC (8260D)
±5 °C ±3% ±0.2 S.U. ±20TimeVolume Purged (Gal)AppearanceTemp.( °C)Diss. Oxygen(mg/L)Sp. Cond.(µS/cm)pH(S.U.)ORP(mV)1356 0.25 clear 20.54 0.66 337 6.38 2371401 0.75 clear 20.0 0.04 326 6.16 2511406 1.25 clear 19.84 0.00 327 6.11 2571411 1.75 clear 19.82 0.00 325 6.09 2611416 2.0 clear 19.80 0.00 326 6.07 264Sample ID Time Analytical Parameter NotesWell Locked?: ☐ Well Unlocked?: XSite: Badin Business Park Well #: MW-5 Total Depth (ft): 17.00BTOC?: X BGS?: ☐Measured?: X Historical?: ☐Personnel: D. Cobb Probe Type: electric Water Depth (ft): 8.30BTOC?: X BGS?: ☐ Well Material: PVC?: XWell Integrity:Good?: X Decontamination Fluids: DI water?: X Liquinox?: X Alconox?: ☐Start Time: 1351 End Time: 1421 Well Diameter (in): 2 Water Column Height (ft):X0.16 Gal/ft (2in)=Gal/Vol:Project #: 300-226 Date: 6/8/23 Pump Type: bladder Pump Depth (ft): 14.50BTOC?: X BGS?: ☐0.65 Gal/ft (4in)1.50 Gal/ft (6in)___ Gal/ft (___in)< 10 NTU or ±10% > 10 Other Field Measurements:Turbidity (NTU)Water Depth(BTOC)13.9 NM2.0 NM0.0 NMNotes:NM - Not Measured0.0 NM0.0 NMABP-MW005-F1001421 Available Cyanide (1677), Fluoride (9056A), F C Fluoride WTR (4500)
±5 °C ±3% ±0.2 S.U. ±20TimeVolume Purged (Gal)AppearanceTemp.( °C)Diss. Oxygen(mg/L)Sp. Cond.(µS/cm)pH(S.U.)ORP(mV)1032 NM NA 21.93 NM 3410 9.89 1351037 NM NA 20.23 NM 2920 10.25 961042 NM NA 20.22 NM 2780 10.23 981047 NM NA 20.22 NM 3040 10.34 1021052 NM NA 20.34 NM 3410 10.46 991057 NM NA 20.46 NM 3880 10.68 851102 NM NA 20.45 NM 4270 10.87 711107 NM NA 20.41 NM 4490 10.93 631112 NM NA 20.46 NM 4720 10.96 581115 NM NA 20.12 NM 4810 11.1 481118 NM NA 20.11 NM 4880 11.05 481121 NM NA 20.39 NM 4940 11.03 471124 NM NA 20.44 NM 4990 11.04 43Sample ID Time Analytical Parameter NotesWell Locked?: ☐ Well Unlocked?: XSite: Badin Business Park Well #: MW-6 Total Depth (ft): 19.45BTOC?: X BGS?: ☐Measured?: ☐ Historical?: XPersonnel: B. Hardin Probe Type: electric Water Depth (ft): 10.30BTOC?: X BGS?: ☐ Well Material: PVC?: XWell Integrity: Good?: XDecontamination Fluids: DI water?: X Liquinox?: X Alconox?: ☐Start Time: 1032 End Time: 1130 Well Diameter (in): 2 Water Column Height (ft):X0.16 Gal/ft (2in)=Gal/Vol:Project #: 300-226 Date: 6/7/2023 Pump Type: bladder Pump Depth (ft): NMBTOC?: ☐ BGS?: ☐0.65 Gal/ft (4in)1.50 Gal/ft (6in)___ Gal/ft (___in)< 10 NTU or ±10% > 10 Other Field Measurements:Turbidity (NTU)Water Depth(BTOC)NA 10.45605 10.85799 10.93Notes:NM - Not MeasuredNA - Not Analyzed 344 11.12234 11.21162 11.32114 11.4285.5 11.43125 11.4231 11.36240 11.42123 11.35235 11.43ABP-MW006-F1001130Available cyanide (1677), fluoride (9056A), F C Fluoride WTR (4500), Br Cl SO4 (9056A), N-Nitrite (353.2), Nitrate + Nitrite (353.2), Nitriate by calc N-Nitrate, Orthophosphate (4500)Total carbonate and bicarbonate alkalinity (2320B), Silica (6010D), Dissolved Meatls Site List (6020B-FF), Dissolved Organic Carbon (5310-FF), TSS (2540)