DSHW-2024-005124

WASATCH ENVIRONMENTAL, INC.
ENVIRONMENTAL SCIENCE AND ENGINEERING

2410 WEST CALIFORNIA AVENUE
SALT LAKE CITY, UTAH 84104
PHONE [phone]
FAX [phone]
e-mail: [e-mail]
www.wasatch-environmental.com

ADDITONAL INVESTIGATION WORK PLAN
ARMS TECHNOLOGY EAST SHOP
1142 SOUTH 2475 WEST
SALT LAKE CITY, UTAH

PROJECT NO. 2619-004C

PREPARED FOR:

MR. DOUG HANSEN
UTAH DEPARTMENT OF ENVIRONMENTAL QUALITY
DIVISION OF WASTE MANAGEMENT AND RADIATION CONTROL
195 NORTH 1950 WEST, 2ND FLOOR
P.O. BOX 144880
SALT LAKE CITY, UTAH 84114-4880

PREPARED BY:

WASATCH ENVIRONMENTAL, INC.
2410 WEST CALIFORNIA AVE
SALT LAKE CITY, UTAH 84104
801-972-8400
FAX: [phone]

MARCH 7, 2024
Arms Technology East Shop
Additional Investigation Work Plan Project No. 2619-004C
Wasatch Environmental, Inc. Page 1

TABLE OF CONTENTS

Section Page No.
1. INTRODUCTION AND OBJECTIVES ............................................................................................. 2
2. SITE BACKGROUND ...................................................................................................................... 2
3. SITE INVESTIGATION ACTIVITIES ................................................................................................ 5
3.1 Groundwater Monitoring Well Installation, Development, Surveying, and Sampling ......... 5
3.2 Off-Site Groundwater Sampling .......................................................................................... 5
3.3 Indoor Air Sampling............................................................................................................. 6
4. SAMPLING METHODOLOGY ......................................................................................................... 6
4.1 Groundwater Monitoring Well Installation, Development, Surveying, and Sampling ......... 6
4.2 Off-Site Groundwater Sampling .......................................................................................... 7
4.3 Indoor Air Sampling............................................................................................................. 7
5. REPORTING .................................................................................................................................... 8

FIGURES

Figure 1 – Site Location Map
Figure 2 – Historical and Proposed Sample Location Map

Arms Technology East Shop
Additional Investigation Work Plan Project No. 2619-004C
Wasatch Environmental, Inc. Page 2
ADDITIONAL INVESTIGATION WORK PLAN
ARMS TECHNOLOGY EAST SHOP
1142 SOUTH 2475 WEST
SALT LAKE CITY, UTAH

1. INTRODUCTION AND OBJECTIVES

In accordance with the Utah Division of Waste Management and Radiation Control (DWMRC) request, we
have prepared this work plan for conducting investigative activities at the Arms Technology east shop
(Site), owned by ATI Corporation, located at 1142 South 2475 West in Salt Lake City, Utah. See Figure 1
for a Site Location Map. This work plan has been prepared to evaluate groundwater flow direction,
evaluate volatile organic compound (VOC) and semi-volatile organic compound (SVOC) impacts to
groundwater at the Site, and evaluate indoor air concentrations at the Site.

The objectives of this work plan are to:

 Install, develop, survey, and sample groundwater monitoring wells at the Site to evaluate the
groundwater flow direction, evaluate on-Site VOC and SVOC impacts to groundwater, and
evaluate the potential for VOC impacts to be migrating onto the Site from an off-Site source; and

 Collect indoor air samples to evaluate the potential for VOC impacts to on-Site commercial
workers.

This work plan describes the sampling and analytical procedures that will be used for sampling to be
performed during investigation activities at the Site.

2. SITE BACKGROUND

Wasatch completed a Phase I Environmental Site Assessment (ESA) dated September 21, 2023, for the
Site on behalf of Buchalter (the legal representative of the potential purchaser of the Site). This report
identified the following recognized environmental conditions (RECs) and recommended additional
investigation be completed:

 There is a potential for releases to the Site from the long-term use of the Site for manufacturing
and as a machine shop.

 There is a potential for releases from the long-term use of adjoining properties for chrome plating
and heavy industrial uses to have impacted the Site.

 There are known chlorinated solvent impacts to groundwater on the south adjoining property that
have likely migrated onto the Site.

On October 25, 2023, Wasatch completed seven soil borings (GP-1 through GP-7) at the Site to evaluate
the identified RECs. Borings GP-1, GP-2, and GP-3 were completed in the areas hydraulically
downgradient from adjoining south/southeast properties where potential impacts may be migrating
towards the Site. Boring GP-4 was completed adjacent to the sump to evaluate potential releases in this
area. Borings GP-5, GP-6, and GP-7 were completed hydraulically downgradient of the building to
evaluate potential releases originating from the building. Additionally, boring GP-5 was completed
adjacent north of the sump located in the shoot tunnel area to evaluate for releases from this feature.
Additionally, Wasatch collected six sub-slab soil gas samples (SG-1 through SG-6) from beneath the on-
Site building.

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Additional Investigation Work Plan Project No. 2619-004C
Wasatch Environmental, Inc. Page 3
Based on the data collected Wasatch concluded the following:

 The suspected source area soil samples (GP-4 and GP-5 completed adjacent to the on-Site
sumps) did not exhibit analyte concentrations that exceeded their applicable United States
Environmental Protection Agency (U.S. EPA) Regional Screening Levels (RSLs) for Residential
or Industrial Soil, except for arsenic. Based on Wasatch’s experience, the detected arsenic
concentrations are within the typical background range of 20 to 30 mg/kg for this area. Therefore,
it is Wasatch’s opinion that the detected concentration of arsenic in soil is within the typical
background concentration range for the area.

 All soil gas samples exhibited trichloroethene (TCE) and tetrachloroethene (PCE) concentrations
that exceed the applicable U.S. EPA Vapor Intrusion Screening Level (VISL) Residential and
Commercial Target Sub-Slab and Near-Source Gas Concentrations (TSSGCs). The TCE and
PCE concentrations in soil gas indicated a release of TCE and PCE has likely occurred near soil
gas samples SG-4 and SG-5. The detected TCE and PCE in soil gas concentrations indicated
there is a potential that the rate of vapor intrusion into the building may result in TCE and PCE
indoor air concentrations that exceed the U.S. EPA RSL for Industrial Air.

 The arsenic concentrations detected in groundwater exceed the U.S. EPA Maximum
Contaminant Level (MCL) and Division of Water Quality (DWQ) Water Quality Standard (WQS).
Given the elevated arsenic in groundwater concentration exhibited by groundwater sample GP-1
(this boring was completed in an assumed hydraulically upgradient location at the Site to evaluate
for impacts migrating onto the Site), it appeared that arsenic-impacted groundwater exceeding
the U.S. EPA MCL was migrating onto the Site. However, based on the GP-7 arsenic
concentration in groundwater there may be a source of arsenic impacts to groundwater near this
boring. No other metals were detected at concentrations that exceed their applicable U.S. EPA
MCLs.

 Based on the GP-1 per- and polyfluoroalkyl substances (PFAS) groundwater data and assumed
hydraulic gradient to the northwest or north, perfluorooctane sulfonic acid (PFOS)-impacted
groundwater is migrating onto the Site at a concentration that exceeds the proposed U.S. EPA
MCL.

 TCE and PCE were detected in groundwater samples GP-2 and GP-3 at concentrations that
exceed their applicable U.S. EPA MCL. These borings were completed on the assumed
hydraulic upgradient boundary to evaluate if chlorinated solvent impacts were migrating onto the
Site. Based on the GP-2 and GP-3 groundwater data, PCE, TCE, and cis-1,2-dichloroethene
(CIS) impacts exceeding the U.S. EPA MCLs appear to be migrating onto the Site from the
southern adjoining property.

 PCE and TCE were detected in groundwater samples GP-5, GP-6, and GP-7 at concentrations
that exceed their applicable U.S. EPA MCLs. These samples were collected hydraulically
downgradient of the on-Site building. Based on these data, it appeared that a release of PCE
and TCE was originating from the on-Site building.

 Based on the data obtained from borings GP-4 and GP-5, it did not appear that a release from
the on-Site sumps has occurred.

 Based on the groundwater data, it appeared that a co-mingled (one potentially originating on-Site
and one potentially originating off-Site) chlorinated solvent plume is present on the Site.

 Given the totality of the data, it appears that a releases of chlorinated solvents and potentially
arsenic have occurred at the Site. Wasatch recommended that these releases be reported to the
Utah Department of Environmental Quality (DEQ). Wasatch also recommended that additional
investigation be completed to define the nature and extent of these impacts.
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Additional Investigation Work Plan Project No. 2619-004C
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On January 8 and 9, 2024, Wasatch completed 11 additional borings (GP-8 through GP-18) at the Site to
further evaluate the on-Site VOC and arsenic impacts to soil and groundwater. Based on the data
Wasatch concluded the following:

 Arsenic was detected in soil samples GP-12-15, GP-13-11, GP-15-7, and GP-17-11 at
concentrations that exceed the U.S. EPA RSL for Residential and Industrial Soil. Based on
Wasatch’s experience the average arsenic concentration in soil at the Site is within the typical
background range of 20 to 30 mg/kg for this area. Arsenic was detected in groundwater samples
GP-8-15, GP-9-15, GP-10-15, GP-12-15, GP-13-15, and GP-17-15 at concentrations that exceed
the U.S. EPA MCL, and the GP-12-15, GP-13-15, and GP-17-15 concentrations exceed the Utah
GQS of 50 µg/L. Given the total arsenic in groundwater data for the Site, it appears that the
source of the groundwater impacts is located under the southwestern portion of the building.
However, local arsenic impacts to groundwater above the U.S. EPA MCL also appear to be
migrating onto the Site from an off-Site source.

 Several VOC soil samples were collected above the water table in suspected source areas. Low
concentrations of TCE and/or PCE were detected in the GP-14 (at 5 feet bgs), GP-15 (at 5 feet
bgs), GP-16 (at 5 feet bgs), and GP-18 (at 5 feet bgs) borings above the water table. This
indicates that minor surface releases have likely occurred in these areas. However, these
detected TCE and PCE concentrations are below the U.S. EPA RSL for Residential and Industrial
Soil but exceed the U.S. EPA Protection of Groundwater Soil Screening Level (PGWSSL).

 No chlorinated solvents (including PCE, TCE, and CIS) were detected at concentrations
exceeding their applicable U.S. EPA RSLs for Residential or Industrial Soil in the soil samples
collected. However, soil samples GP-12-10, GP-13-1-0, GP-14-10, GP-14-15, GP-15-10, GP-15-
15, GP-16-10, GP-16-15, GP-17-10, GP-17-20, , GP-18-10, and GP-18-15 (all collected at or
below the water table) exhibited PCE and TCE concentrations that exceed the U.S. EPA
PGWSSL. This indicates there are soil impacts below the water table at sufficient concentrations
to result in impacts to groundwater at concentrations that exceed the U.S. EPA MCL.

 TCE and/or PCE were detected in all groundwater samples analyzed for VOCs at concentrations
that exceed their applicable U.S. EPA MCLs. Additionally, CIS (a breakdown product of PCE and
TCE) was detected at concentrations above the U.S. EPA MCL in groundwater samples GP-13-
15 and GP-17-15. Based on the groundwater data, PCE and TCE impacts to groundwater
appear to be present across the Site.

 Based on the totality of the groundwater data, PCE and TCE were detected along the northern,
western, eastern, and southern boundaries of the Site. This indicates that PCE and TCE impacts
may be migrating onto the Site, as the local groundwater flow direction is unknown but was
assumed to be to the north or northwest. Additionally, groundwater samples GP-9-15 and GP-8-
15 exhibited the highest detections of PCE and TCE, respectively. These samples were collected
along the western Site boundary. Based on the concentration gradients of PCE and TCE, it
appears that the majority of the PCE and TCE impact may be originating from the adjoining west
property and migrating to the east to northeast across the Site. Groundwater monitoring wells
should be installed to verify the groundwater flow direction.

 Three groundwater samples (GP-12-30, GP-13-30, and GP-17-30) were collected at a depth of
30 feet bgs beneath the building. PCE (ranging from 30.2 to 641 µg/L) and TCE (ranging from
5.87 to 116 µg/L) were detected at concentrations that exceed the U.S. EPA MCL. This indicates
that PCE and TCE impacts have migrated to a depth of at least 30 feet bgs at the Site.

 PFAS were not detected in any of the groundwater samples collected beneath the building.
Therefore, it does not appear that the PFAS impacts detected on the southeast corner of the Site
originate from the building.

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Additional Investigation Work Plan Project No. 2619-004C
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 Given the totality of the data, it appears that minor releases of PCE and TCE have occurred at
the Site beneath the building. Additionally, it appears that the highest PCE and TCE impacts are
potentially migrating onto the Site from an off-Site source. Also, arsenic concentrations in
groundwater beneath the building appear to be elevated above the local concentrations
observed. Wasatch recommends that these releases be reported to the Utah DEQ. Wasatch
also recommends that additional investigation be completed including the installation of
groundwater monitoring wells to define the nature and extent of these impacts under the
guidance of the Utah DEQ.

Wasatch submitted a DWMRC application to enter into regulatory oversight with the Utah DWRMC on
February 20, 2024. The Site was accepted into the DWMRC Corrective Action program. DWMRC
requested that additional environmental investigations be completed.

3. SITE INVESTIGATION ACTIVITIES

3.1 Groundwater Monitoring Well Installation, Development, Surveying, and Sampling

Groundwater monitoring wells will be installed at the Site to evaluate VOC impacts to groundwater at the
Site and to evaluate the potential for VOC impacts that may be migrating onto the Site from an off-Site
source. The monitoring wells will be installed using the direct-push drilling methods. Soil core samples
would be continuously collected from 5-foot long by 1.5-inch diameter discrete interval push samplers
equipped with disposable polybutyrate liners. Soil samples would be collected continuously and field
logged by an experienced geologist. The field logging would include a description of color, moisture
content, consistency, odor, staining, and soil type based on the Unified Soil Classification System and
screened in the field with a photoionization detector (PID).

Monitoring well construction will consist of a 2.0-inch inner diameter (I.D.) polyvinyl chloride (PVC) well
with a 10-foot screen to a depth of approximately 15 to 20 feet below ground surface. The monitoring
wells will be developed to remove fines from the well screen prior to sampling using a pump or a
disposable polyethylene bailer.

In order to determine groundwater flow direction at the facility, top-of-casing elevations will be surveyed
by Wasatch personnel using traditional survey equipment at each monitoring well location to within 0.01-
foot. Wasatch will obtain groundwater elevation measurements from each monitoring well using an
electronic water level probe. The probe will be decontaminated between each monitoring well with a
phosphate-free soap, rinsed with potable water, and then rinsed with de-ionized water. Based on the
measurements obtained, Wasatch will construct a potentiometric surface elevation contour map to
determine groundwater flow direction.

3.2 Off-Site Groundwater Sampling

Wasatch will request that two soil borings be completed on the adjoining west, assumed hydraulically
upgradient, property. Groundwater samples will be collected from these borings to evaluate VOC and
SVOC impacts to groundwater that may be migrating onto the Site from an off-Site source. The borings
will be installed using the direct-push drilling methods. Soil core samples would be continuously collected
from 5-foot long by 1.5-inch diameter discrete interval push samplers equipped with disposable
polybutyrate liners. Soil samples would be collected continuously and field logged by an experienced
geologist. The field logging would include a description of color, moisture content, consistency, odor,
staining, and soil type based on the Unified Soil Classification System and screened in the field with a
PID.

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3.3 Indoor Air Sampling

To evaluate the potential risk to indoor air for commercial workers, Wasatch will collect indoor air samples
within the on-Site building.

To evaluate current background VOC concentrations present in ambient air in the vicinity of the Site so
that comparisons can be made to indoor air concentrations present at the on-Site building, Wasatch will
collect an outdoor air sample from the roof or an upwind area of the building.

4. SAMPLING METHODOLOGY

4.1 Groundwater Monitoring Well Installation, Development, Surveying, and Sampling

Chlorinated solvents have been identified at concentrations exceeding its U.S. EPA MCL within the
groundwater beneath the Site. Therefore, Wasatch proposes installing six groundwater monitoring wells
to achieve the stated objectives. The monitoring wells will be installed using the direct-push drill rig
(GeoProbe 7822 or equivalent), using hollow-stem auger or direct-push drilling techniques. Wasatch
proposes installing the following monitoring wells as depicted in Figure 2.

Each well will be installed to a depth ranging between 15 and 20 feet below ground surface (bgs)
depending on measured depth to groundwater. Each well will be completed with 10 feet of 2-inch 0.010-
slot schedule 40 polyvinyl chloride (PVC) wells screen with 2-inch PVC well casing attached to the top of
the well screen and extending to approximately 0.5 feet bgs. 10/20 silica sand will be placed as a filter
pack material around the screen interval and extending at least 2 feet above the top of the screen
interval. Bentonite chips will be placed from the top of the filter pack material up to ground surface and
hydrated to form a well seal. Each well will be completed with a flush-mount surface completion
consisting of a 8-inch steel well vault cemented in place.

Once each well is installed, each well will be properly developed using over pumping well development
techniques. A minimum of five well casing volumes of groundwater will be evacuated from each well;
however, additional volume will be removed to sufficiently remove additional fines from the wells based
on Wasatch’s discretion. All evacuated groundwater will be placed within a steel 55-gallon drum(s)
labeled as pending analysis to facilitate proper disposal. All soil cuttings will also be placed within a steel
55-gallon drum and labeled as pending analysis to facilitate proper disposal.

In order to determine groundwater flow direction at the Site, top-of-casing elevations will be surveyed by
Wasatch personnel using traditional survey equipment at each monitoring well location to within 0.01-foot.
Wasatch will survey the top-of-casing of each well and reference them to a relative datum of 100.00 feet.
Wasatch will obtain groundwater elevation measurements from each monitoring well using an electronic
water level probe. The probe will be decontaminated between each monitoring well with a phosphate-
free soap, rinsed with potable water, and then rinsed with de-ionized water. Based on the measurements
obtained, Wasatch will construct a potentiometric surface elevation contour map to determine
groundwater flow direction.

The monitoring wells will be sampled using low-flow sampling techniques. Monitoring well sampling will
involve inserting ¼-inch outside diameter, low-density polyethylene tubing into the newly installed
monitoring well. The tubing will be run through a peristaltic pump, then to a flow cell to which a multi-
parameter AquaTroll 500 meter will be attached, and finally to a 5-gallon bucket to collect the purge
water. The initial water level would be measured in the monitoring well only and recorded prior to the
initiation of pumping. Once pumping is initiated, water levels, pumping rate, cumulative volume purged,
water temperature, specific conductivity, pH, oxygen reduction potential (ORP), dissolved oxygen (DO),
and turbidity will be recorded at three to five-minute intervals until either stabilization is achieved or the
monitoring well pumps dry. Pumping rates will be maintained at rates of 50 to 200 milliliters per minute to
minimize drawdown. Stabilization is defined as three consecutive measurement intervals where
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temperature and specific conductivity were +/- 3%, pH was +/- 0.1, DO was +/-10% (or less than 0.5
mg/L), and turbidity was +/- 10% (or less than 5 nephelometric turbidity units [NTUs]). If the monitoring
well pumps dry, it will be allowed to recharge to a minimum of at least 90% of its static water level prior to
sampling. After stabilization is achieved, the tubing would be disconnected from the flow cell and the
groundwater sample would be dispensed into appropriate laboratory prepared containers.

Groundwater samples would be collected into appropriate containers with gloved hands and transported
under chain-of-custody, in an iced cooler to Chemtech-Ford Laboratories (CF) for analysis of VOCs using
U.S. EPA Method 8260D and SVOCs using U.S. EPA Method 8270E.

4.2 Off-Site Groundwater Sampling

These borings will be installed using the direct-push drilling methods. Soil core samples would be
continuously collected from 5-foot long by 1.5-inch diameter discrete interval push samplers equipped
with disposable polybutyrate liners. Soil samples would be collected continuously and field logged by an
experienced geologist. The field logging would include a description of color, moisture content,
consistency, odor, staining, and soil type based on the Unified Soil Classification System and screened in
the field with a PID.

Subsequent to the borings, a stainless-steel temporary well screen will be placed within the groundwater
to collect a groundwater sample. Groundwater would be purged from the boring in an attempt to reduce
the turbidity of the groundwater sample.

Groundwater samples would be collected into appropriate containers with gloved hands and transported
under chain-of-custody, in an iced cooler to CF for analysis of VOCs using U.S. EPA Method 8260D and
SVOCs using U.S. EPA Method 8270E.

Given that the adjoining west property owners may reject our request to collect groundwater samples
from their property. These borings may not be collected. Wasatch will provide proof of acceptance or
rejection of our request to sample the adjoining west property.

4.3 Indoor Air Sampling

To evaluate potential soil vapor intrusion impacts in the on-Site building, Wasatch would collect six indoor
air samples, four within the warehouse/manufacturing area (IA-1 through IA-4) on the ground floor level
and two in the office areas (IA-5 and IA-6), and one outdoor air sample (OA-1) to be used as a
background sample. Proposed sample locations are shown in Figure 2.

Prior to collecting any indoor or outdoor air samples, Wasatch would complete a chemical inventory of the
interior of the building space at the Site. This would be done to verify that no products within the structure
contain any chemicals of concern. If products are found that contain the same chemicals of concern we
will be analyzing for, those products will be removed from the building for at least 7 days prior to
sampling. This will be completed to reduce the potential for false positives within the indoor air samples.
Wasatch would also interview the appropriate personnel to ascertain if potential activities within the
beginning have been conducted that may result in false positives (i.e. recent remodeling, floor stripping,
etc.)

The technique for collecting the indoor/outdoor air samples would begin by checking for a vacuum in each
6-liter Summa canister supplied by the laboratory. The initial vacuum would be recorded on the chain-of-
custody form. A 6-liter Summa canister would then be placed at an appropriate height for each sample
location. The sampling location height will generally be placed at breathing space height. A sample
regulator with a flow restrictor would be provided by the laboratory. A sample regulator would be
attached to each 6-liter Summa canister. The vacuum gauge on the flow restrictor would be monitored,
with decreasing vacuum indicating that ambient indoor air is being collected into the sample canister. The
samples would be collected for approximately 8 hours to represent a standard workday. The final
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vacuums would be recorded on the chain-of-custody form provided. The valve on each Summa canister
would then be closed, the sample regulator would be removed, and a brass cap tightened to the inlets of
the Summa canisters. The Summa canisters would be labeled with the appropriate sample location, as
well as initial and final vacuum reading. Chain-of-custody documentation would be completed and the
samples would be delivered to Pace Analytical (Pace) for the analysis of the standard list of VOCs using
U.S. EPA Method TO-15.

The laboratory will use level 3 quality assurance/quality control (QA/QC) reporting. A Data Validation
Report will be completed by an independent third-party for the groundwater, indoor air, and outdoor air
sample samples.

5. REPORTING

All data generated during the sampling will be documented in a final report. This report will include the
following:

 Narrative text,

 Data table,

 Boring/well construction logs,

 Applicable maps,

 Chain of custody forms,

 Laboratory analytical results, and

 Third-party data validation report.

The results of the sampling and analysis will be summarized in the report. Data will be presented in table
format. Conclusions based on the data as well as field observations will be included in the report. After
the laboratory data has been received, and reviewed, the report will be completed and submitted to ATI
Corporation prior to submission to the Utah DWMRC.

Sincerely,

WASATCH ENVIRONMENTAL, INC.

Blake Downey, P.G.
Vice President and Senior Project Hydrogeologist

Distribution: (1) Electronic - Addressee
(1) Electronic – Scott Farber (ATI Corporation)

The use or reuse of this information is restricted to the referenced document unless otherwise authorized.
Wasatch Environmental Copyright 2006
ARMS TECHNOLOGY EAST SHOP WEI 2619-004C
Figure 1 Site Location Map
Approximate
Location of Site
The use or reuse of this information is restricted to the referenced document unless otherwise authorized.
Wasatch Environmental Copyright 2006
ARMS TECHNOLOGY EAST SHOP WEI 2619-004C
Historical and Proposed Sample Location Map Figure 2
Approximate Location of Site
24
7
5

W
es
t
Storm water lift station
Totes of coolant
Sump and
drain pad
Shoot tunnel
Sump
Parts washer
SG-1
SG-3
SG-4
SG-2 SG-5
SG-6
GP-2
GP-1
GP-7
GP-5
GP-3
GP-6
GP-4
Previous Boring Location
Previous Soil Gas Sample Location
LEGEND
GP-8
GP-9
GP-10 GP-11
GP-12
GP-13GP-14
GP-15
GP-16
GP-17
GP-18
Proposed Monitoring Well Location
MW-3
MW-4
MW-2
MW-1
MW-5
MW-6
Proposed Indoor/Outdoor Air Sample Location
IA-3
IA-4 IA-5
IA-2IA-1 IA-6
OA-1
Scale: 1-inch equals
approximately 51 feet
Assumed Groundwater
Flow Direction
GP-19
GP-20
Proposed Off-Site Boring Location