DERR-2025-001532

SUBSURFACE INVESTIGATION REPORT
7-Eleven No. 47151
Facility ID 4000775, Release Site OLK
1344 Fort Union Boulevard,
Cottonwood Heights, Utah
February 28, 2025

Prepared for:
7-Elevan Inc.
Submitted to:
Alex Jones
Utah Department of Environmental Quality
Division of Environmental Response and Remediation
195 North 1950 West, 1st Floor
P.O. Box 144840
Salt Lake City, Utah
Prepared by:
Stantec Consulting Services Inc.
2890 East Cottonwood Parkway
Suite 300
Salt Lake City, Utah
Project Number:
203724146

The conclusions in the Report titled Subsurface Investigation Report, 7-Elevan No. 47151 are Stantec’s
professional opinion, as of the time of the Report, and concerning the scope described in the Report. The
opinions in the document are based on conditions and information existing at the time the scope of work
was conducted and do not take into account any subsequent changes. The Report relates solely to the
specific project for which Stantec was retained and the stated purpose for which the Report was prepared.
The Report is not to be used or relied on for any variation or extension of the project, or for any other project
or purpose, and any unauthorized use or reliance is at the recipient’s own risk.
Stantec has assumed all information received from 7-Elevan Inc. (the “Client”) and third parties in the
preparation of the Report to be correct. While Stantec has exercised a customary level of judgment or due
diligence in the use of such information, Stantec assumes no responsibility for the consequences of any
error or omission contained therein.
This Report is intended solely for use by the Client in accordance with Stantec’s contract with the Client.
While the Report may be provided by the Client to applicable authorities having jurisdiction and to other
third parties in connection with the project, Stantec disclaims any legal duty based upon warranty, reliance
or any other theory to any third party, and will not be liable to such third party for any damages or losses of
any kind that may result.
Prepared by:

Signature
Ally Auffermann, Environmental Engineer
Printed Name
Reviewed by:

Signature
Anna Skinner, Project Manager
Printed Name
Approved by:

Signature
John Wainwright, Senior Principal
Printed Name
Project Number: 203724146 i

Table of Contents
EXECUTIVE SUMMARY .............................................................................................................. ii
1 INTRODUCTION ............................................................................................................ 3
1.1 Site Background ............................................................................................................................ 3
2 SUBSURFACE INVESTIGATION SCOPE AND METHODS ......................................... 5
2.1 Soil Boring Advancement and Soil Sampling ................................................................................ 5
2.2 Groundwater Monitoring Well Installation and Groundwater Sampling ........................................ 6
3 RESULTS ....................................................................................................................... 8
3.1 Soil ................................................................................................................................................. 8
3.2 Groundwater .................................................................................................................................. 8
4 CONCLUSIONS AND RECOMMENDATIONS .............................................................. 9

LIST OF FIGURES
Figure 1 .............. Site Map

LIST OF TABLES
Table 1 .............. Soil Analytical Results
Table 2 ............... Groundwater Analytical Results

LIST OF APPENDICES
Appendix A ......... Boring Logs
Appendix B ......... Laboratory Analytical Reports and Chain-of-Custody Documentation

Subsurface Investigation Report – 7-Eleven No. 47151
Facility ID 4000775, Release Site OLK
1344 Fort Union Boulevard, Cottonwood Heights, Utah
Introduction
Project Number: 203724146 ii

EXECUTIVE SUMMARY
This report presents the results of a subsurface investigation conducted by Stantec Consulting Services
Inc. (Stantec) at 7-Eleven Inc. (7-Eleven) Store No. 47151 (the Site) located at 1344 Fort Union Boulevard,
Cottonwood Heights, Utah (Figure 1). The Utah Department of Environmental Quality (UDEQ), Division of
Environmental Response and Remediation (DERR) refers to the Site as Facility ID 4000775, Release Site
OLK. The objectives of this investigation were to assess the horizontal and vertical extent of potential
petroleum hydrocarbon impacts to soil and groundwater in the vicinity of the former underground storage
tanks (USTs).
The former UST system was installed in 2014 and closed by removal on June 26, 2024. The former UST
system was located in the center of the property (Figure 1) and consisted of one 15,000-gallon gasoline
UST, one split compartment UST (with one 8,000-gallon gasoline compartment and one 7,000-gallon diesel
compartment), and four product dispensers.
Previous petroleum hydrocarbon releases have been documented at the Site. All previous petroleum
releases have received closure from DERR with varying levels of remaining petroleum hydrocarbon
impacts.
In October 2024, Release Site OLK was opened based on analytical laboratory results of UST closure
samples which contained dissolved petroleum hydrocarbon concentrations above the screening levels
established by the UDEQ DERR Petroleum Storage Tank (PST) Branch. Groundwater samples GW-1 and
GW-2 (Figure 1) contained benzene, toluene, total petroleum hydrocarbons (TPH) gasoline range organics
(GRO), and TPH diesel range organics (DRO) concentrations above the Initial Screening Levels (ISLs).
The benzene concentration of the GW-1 sample also exceeded the Tier 1 Screening Level (TSL).
Stantec submitted a work plan and budget (WP&B) for subsurface investigation which was approved by
UDEQ-DERR for reimbursement from the Petroleum Storage Tank (PST) Fund on January 16, 2025 as
WP&B OLK-01.
Stantec conducted subsurface investigation activities in January 2025. Three direct-push soil borings were
advanced by Pacific West. One soil boring was completed as groundwater monitoring well MWOLK-3. The
soil boring and monitoring well locations are shown on Figure 1.
Soil and groundwater samples were submitted to Utah-certified Pace Analytical National Laboratories
(Pace) of Mount Juliet, Tennessee for analysis of methyl tertiary-butyl ether, benzene, toluene,
ethylbenzene, total xylenes, and naphthalene (MBTEXN) by EPA Method 8260 and TPH-GRO and TPH-
DRO by EPA Method 8015.
All soil and groundwater petroleum hydrocarbon concentration results reported by Pace were below the
Initial Screening Levels (ISLs) established by the UDEQ-DERR, with the with the exception of the duplicate
sample from monitoring well MWOLK-3 that had a dissolved TPH-GRO concentration slightly above the
ISL. Based on current Release Site OLK subsurface investigation results and the previous release history
of the Site Stantec recommends Release Site OLK be closed with no further action required.
Subsurface Investigation Report – 7-Eleven No. 47151
Facility ID 4000775, Release Site OLK
1344 Fort Union Boulevard, Cottonwood Heights, Utah
Introduction
Project Number: 203724146 3

1 INTRODUCTION
On behalf of 7-Elevan, Inc. (7-Elevan) Stantec Consulting Services Inc. (Stantec) has prepared the following
report based on subsurface investigation activities performed at the 7-Elevan Store No. 47151 (the Site),
located at 1344 Fort Union Boulevard, Cottonwood Heights, Utah. The Utah Department of Environmental
Quality (UDEQ), Division of Environmental Response and Remediation (DERR) refers to the Site as Facility
ID 4000775, Release Site OLK.
Subsurface investigation activities were conducted in general accordance with Work Plan and Budget No.
(WP&B) OLK-01, which the UDEQ-DERR approved for reimbursement from the Petroleum Storage Tank
(PST) Fund on January 16, 2025. The objectives of this investigation were to assess the horizontal and
vertical extent of potential petroleum hydrocarbon impacts to soil and groundwater in the vicinity of the
former underground storage tanks (USTs).
1.1 Site Background
The former UST system was installed in 2014 and closed by removal on June 26, 2024. Stantec provided
DERR certified UST consultant and sampling services and oversaw the DERR certified UST remover
contractor (Pacific West). The former UST system was located in the center of the property (Figure 1) and
consisted of one 15,000-gallon gasoline UST, one split compartment UST (with one 8,000-gallon gasoline
compartment and one 7,000-gallon diesel compartment), and four product dispensers.
In October 2024, Release Site OLK was opened based on analytical laboratory results of UST closure
samples which contained dissolved petroleum hydrocarbon concentrations above the screening levels
established by the UDEQ DERR Petroleum Storage Tank (PST) Branch. Groundwater samples GW-1 and
GW-2 (Figure 1) contained benzene, toluene, total petroleum hydrocarbons (TPH) gasoline range organics
(GRO), and TPH diesel range organics (DRO) concentrations above the Initial Screening Levels (ISLs).
The benzene concentration of the GW-1 sample also exceeded the Tier 1 Screening Level (TSL).
Previous petroleum hydrocarbon releases have been documented at the Site. Release Site HKB was
opened in February 1992 based on exploratory site assessment soil and groundwater analytical results
above DERR screening levels from samples collected north of the UST basin. Based on fuel inventory
records and no history of failed tank or line tightness tests the source of Release Site HKB subsurface
petroleum hydrocarbon impacts was assumed to be UST overfills. Release Site HKB received Teir 1 closure
in November 1998. The highest dissolved TPH-GRO concentration detected during the final groundwater
monitoring event for Release Site HKB was 1.04 mg/L collected from a monitoring well near the northern
edge of the UST basin.
Release Site IUK was opened in December 1994 based on a failed line tightness test for one of the
unleaded gasoline USTs present at the Site at that time. Release Site IUK was closed in August 1996
based on a passing line tightness test. No specific investigation was ever conducted for nor were any
subsurface petroleum hydrocarbon impacts directly attributed to Release Site IUK. Stantec assumes this
Subsurface Investigation Report – 7-Eleven No. 47151
Facility ID 4000775, Release Site OLK
1344 Fort Union Boulevard, Cottonwood Heights, Utah
Introduction
Project Number: 203724146 4

is because any subsurface petroleum hydrocarbon impacts caused by Release Site IUK would be
investigated as part of the ongoing investigation of Release Site HKB.
Release Site MXM was opened in May 2012 after a DERR inspector discovered a leaking meter on the
southeastern most diesel dispenser. Subsurface investigation results did not indicate any TPH-DRO
petroleum hydrocarbon impacts were present above DERR screening levels; subsurface TPH-GRO
impacts above DERR screening levels were encountered and attributed the previously documented
gasoline releases. Release Site MXM was granted risk-based closure in April 2013.
Release Site NDE was opened in May 2014 based on UST system closure sampling soil and groundwater
analytical results above DERR screening levels. Impacted soil and groundwater were removed during the
UST system closure. Petroleum hydrocarbon concentrations of soil confirmation samples collected
following excavation were below TSLs but above ISLs. Following installation of a new UST system, one
groundwater monitoring well was installed north of the UST basin; these groundwater analytical results
were below ISLs. Release Site NDE was granted risk-based closure in June 2016.

Subsurface Investigation Report – 7-Eleven No. 47151
Facility ID 4000775, Release Site OLK
1344 Fort Union Boulevard, Cottonwood Heights, Utah
Subsurface Investigation Scope and Methods
Project Number: 203724146 5

2 SUBSURFACE INVESTIGATION SCOPE AND METHODS
This section describes the scope of the subsurface investigation and the methods used.
2.1 Soil Boring Advancement and Soil Sampling
A Blue Stakes ticket was initiated prior to the subsurface investigation, and companies with no utilities within
the proposed drilling area responded as such. Companies with underground utilities in the area responded
to the ticket and marked their utilities within the Blue Stakes ticket notification area. Proposed boring
locations were adjusted as necessary due to proximity of underground utilities.
On January 16, 2025, direct push soil borings were advanced at three of the four proposed subsurface
investigation monitoring well locations described in WP&B OLK-01. The proposed monitoring well location
MWOLK-4 was not advanced due to obstruction of drill rig access by the fuel canopy. Soil samples were
not collected from nor could monitoring wells be installed at proposed monitoring well locations MWOLK-1
and MWOLK-2. The difficult soil sampling conditions and inability to install monitoring wells at these
locations were caused by a combination of the presence of a significant amount pea gravel previously used
as fill material in the vicinity of the former UST system and the high water table at the Site. The wet pea
gravel could not be retained in the acetate soil core sample sleeves to be brought to the surface. The wet
pea gravel also forced the PVC well casing out of the subsurface during the attempted MWOLK-1
installation. These conditions also caused significant sloughing of the excavation walls during the UST
system removal in June 2024.
Soil borings were advanced at proposed monitoring well locations MWOLK-1 and MWOLK-2 for the
purpose of collecting groundwater samples; therefore, these locations have been designated as soil borings
locations instead of groundwater monitoring well locations throughout this subsurface investigation report.
Soil boring location SBOLK-1 was advanced to a depth of 15 feet below ground surface (bgs). For soil
boring location SBOLK-2, refusal was encountered at 10 feet bgs at the initial location of SBOLK-2N, and
at 14 feet bgs at the secondary location of SBOLK-2S.
Boring location MWOLK-3 was successfully advanced to 15 feet bgs with soil samples collected from two,
nine, and 15 feet bgs. Intact soil cores were collected using a discrete interval drive sampler equipped with
a 5-foot long clear acetate sleeve. Drill casing was decontaminated between boring locations, and a new
disposal acetate sleeve was used for each sampling interval. Soil cores were logged by a Stantec geologist
in accordance with the Unified Soil Classification (USC) System. Soil samples were field screened for
volatile organic compounds using a Minirae 3000 photoionization detector (PID). PID results were used to
select soil sampling intervals. One soil sample was collected from the depth exhibiting the highest level of
petroleum hydrocarbon impacts or the capillary fringe. Two additional samples were collected with the
objective of collecting a nonimpacted sample from both above and below the impacted zone.
Representative soil samples were collected into clean laboratory-supplied sample jars. The Stantec
sampler donned new disposable nitrile gloves between each sample. Each sample jar was filled in a
manner to minimize headspace and sealed with a Teflon™ lined screw cap. Each sample jar was then
Subsurface Investigation Report – 7-Eleven No. 47151
Facility ID 4000775, Release Site OLK
1344 Fort Union Boulevard, Cottonwood Heights, Utah
Subsurface Investigation Scope and Methods
Project Number: 203724146 6

labeled with sample identification, type of analysis, date, and time of sampling, stored in an ice-chilled
cooler, and held under chain-of-custody protocol by Stantec personnel until they could be transferred to the
project laboratory’s courier service in Salt Lake City. Samples were then shipped by the project laboratory’s
courier service to Utah-certified Pace Analytical National Laboratories (Pace) of Mount Juliet, Tennessee
for analysis of total solids by Standard Method 2540G, methyl tertiary-butyl ether, benzene, toluene,
ethylbenzene, total xylenes, and naphthalene (MBTEXN) by EPA Method 8260, and TPH-GRO and
TPH-DRO by EPA Method 8015.
2.2 Groundwater Monitoring Well Installation and Groundwater
Sampling
Soil borings SBOLK-1, SBOLK-2N, and SBOLK-2S could not be completed as a monitoring wells due to
pea gravel surrounding the borehole preventing the proper installation of well screen and casing. Grab
groundwater samples were collected from within the drill casing at SBOLK-1, SBOLK-2N, and SBOLK-2S
via peristaltic pump. New disposable sample tubing was used at each location. Stantec does not consider
it a data gap that no soil boring was advanced and no groundwater sample could be collected at the
MWOLK-4 location. The primary purpose of MWOLK-4 was do provide delineation between previous
upgradient releases if necessary.
Soil boring MWOLK-3 was subsequently completed as a 15-foot deep, 2-inch diameter monitoring well with
10 feet of 0.010-inch slotted screen from 5 to 15 feet bgs. The well was completed with 10/20 silica sand
filter pack to two feet above the top of screen, bentonite seal to one foot below grade, and 8-inch diameter
flush mount well vault installed within a 2-foot square concrete pad. Monitoring well MWOLK-3 was
developed by removing six well volumes of groundwater via a weighted disposable bailer. Following well
development, a groundwater sample was collected from monitoring well MWOLK-3 via bailer. Water
produced from the drilling process and purged groundwater was contained in a 55-gallon steel drum and
stored in the on-site trash enclosure for future disposal by Sump & Trap Cleaning, LLC of Salt Lake City,
Utah.
Groundwater samples were collected into clean laboratory-supplied volatile organic analysis (VOA) sample
containers. Each VOA container was filled in a manner to eliminate headspace and sealed using a screw
cap with a silicone septum. Each VOA sample container was labeled with sample identification, type of
analysis, date, and time of sampling, stored in an ice-chilled cooler, and held under chain-of-custody
protocol by Stantec personnel until they could be transferred to Pace’s courier service in Salt Lake City.
Samples were then shipped by the Pace’s courier service to Pace’s Mount Juliet, Tennessee laboratory for
analysis of MBTEXN by EPA Method 8260 and TPH-GRO and TPH-DRO by EPA Method 8015 (The
groundwater sample from MWOLK-2N was only analyzed for TPH-GRO and MBTEXN by EPA
Method 8260 as insufficient volume was collected for analysis by EPA Method 8015.)
Quality assurance / quality control (QA/QC) samples for the groundwater sampling activities included a
duplicate sample and trip blank. The duplicate was collected from MWOLK-3 and was analyzed for
MBTEXN by EPA Method 8260 and TPH-GRO and TPH-DRO by EPA Method 8015. Pace provided a trip

Subsurface Investigation Report – 7-Eleven No. 47151
Facility ID 4000775, Release Site OLK
1344 Fort Union Boulevard, Cottonwood Heights, Utah
Subsurface Investigation Scope and Methods
Project Number: 203724146 7

blank VOA container that was filled with deionized water and sealed at the laboratory. The trip blank
accompanied the sample VOA containers during shipment to Stantec, sample collection, and return
shipment to Pace. The trip blank sample was only analyzed for volatile organic compounds (TPH-GRO
and MBTEXN) by EPA Method 8260.

Subsurface Investigation Report – 7-Eleven No. 47151
Facility ID 4000775, Release Site OLK
1344 Fort Union Boulevard, Cottonwood Heights, Utah
Results
Project Number: 203724146 8

3 RESULTS
This section describes the field and analytical results obtained from this subsurface investigation. These
results were used to evaluate the vertical and lateral extent of petroleum hydrocarbon impacts in soil and
groundwater.
3.1 Soil
Native soils encountered during this investigation consist primarily of gravels, sands, silts, and clays. Only
road base and pea gravel backfill materials were encountered at SBOLK-1, SBOLK-2N, and SBOLK-2S.
Native gravelly sand (SP) and silty clay (CL) were encountered at MWOLK-3. A boring log containing boring
methods, geologic descriptions, USC System descriptions, depth to groundwater observations, and well
completion details of MWOLK-3 is presented in Appendix A.
Soil laboratory analytical reports and chain-of-custody documentation are included in Appendix B. Soil
analytical results are tabulated in Table 1. TPH-GRO was detected in the sample collected from nine feet
bgs at MWOLK-3 at a concentration below the ISL. All other soil petroleum hydrocarbon concentrations
were below the laboratory reported detection limits (RDLs), and all laboratory RDLs were below ISLs.
3.2 Groundwater
After well installation on January 16, 2025, the static groundwater in well MWOLK-3 was measured at a
depth of 7.78 feet below top of casing using a battery-powered water level meter. The static groundwater
depths at other locations were not gauged due to failure to install monitoring wells.
Groundwater laboratory analytical reports and chain-of-custody documentation are included in
Appendix B. Groundwater analytical results are tabulated in Table 2 and summarized below:
 Dissolved TPH-GRO was detected at concentrations of 0.503 and 1.02 milligrams per liter (mg/L) in
the primary groundwater sample and duplicate groundwater sample, respectively, collected from
monitoring well MWOLK-3. The detected concentration of the duplicate sample is slightly above the
ISL of 1.0 mg/L. The relative percent difference (RPD) between the two samples was 68%, which is
higher than the generally accepted standard of 30%. Pace could not provide an explanation for the
poor RPD between the MWOLK-3 primary and duplicate samples.
 Dissolved TPH-DRO was detected in the groundwater samples collected from SBOLK-1, SBOLK-2N,
and SBOLK-2S; however, all concentrations were below the ISL of 1.0 mg/L.
 No other dissolved petroleum hydrocarbon concentrations were reported above the laboratory RDLs,
and all laboratory RDLs were below ISLs.
 No dissolved petroleum hydrocarbon concentrations were reported above the laboratory RDLs in the
trip blank.

Subsurface Investigation Report – 7-Eleven No. 47151
Facility ID 4000775, Release Site OLK
1344 Fort Union Boulevard, Cottonwood Heights, Utah
Conclusions and Recommendations
Project Number: 203724146 9

4 CONCLUSIONS AND RECOMMENDATIONS
Stantec recommends Release Site OLK be closed with no further action required. Results of the subsurface
investigation conducted in January 2025 indicate that all on-site petroleum hydrocarbon concentrations in
soil and groundwater are below ISLs, with the exception of the duplicate groundwater sample result from
monitoring well MWOLK-3. The detection of TPH-GRO above the ISL in the duplicate sample collected
from MWOLK-3 may be attributed to the previous release history of the Site but could also be a result of
inherent analytical error.
Previous Release Site NDE was closed with soil petroleum hydrocarbon impacts present at concentrations
above ISLs in the vicinity of the southeastern and northwestern most dispensers. Those soil impacts may
still be contributing to petroleum hydrocarbon impacts in groundwater in the vicinity of MWOLK-3. Release
Site OLK should qualify for closure under the same merits as previous releases at Facility ID 4000775.
Pace could not provide an explanation for the poor RPD between the MWOLK-3 primary and duplicate
samples. It is reasonable to assume that the actual dissolved TPH-GRO concentration of groundwater in
the vicinity of MWOLK-3 is between the primary and duplicate sample results of 0.503 and 1.02 mg/L,
respectively, and likely below the ISL.
Stantec will await the UDEQ-DERR decision regarding Release Site OLK. Following receipt of a No Further
Action Letter and at the request of the UDEQ-DERR, Stantec will prepare a WP&B for site closure activities
to abandon monitoring well MWOLK-3.

Subsurface Investigation Report – 7-Eleven No. 47151
Facility ID 4000775, Release Site OLK
1344 Fort Union Boulevard, Cottonwood Heights, Utah
Figures
Project Number: 203724146

FIGURES
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CANOPY/DISPENSERS
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7-ELEVEN
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East Fort Union BLVD
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APPROXIMATE SCALE IN FEET
No warranty is made by Stantec as to the accuracy, reliability, or completeness of these data. Original data were compiled from
various sources. This information may not meet National Map Accuracy Standards. This product was developed electronically, and
may be updated without notification. Any reproduction may result in a loss of scale and or information.
FILEPATH:C:\Users\CCLEE\Desktop\7-11 AUTOCAD\7-11_No.47151.dwg|cclee|Feb 28, 2025 at 11:04|Layout: SM
410 17th Street Suite 1400
Denver, Colorado 80202
LEGEND:
APPROXIMATE PROPERTY BOUNDARY
NATURAL GAS LINE
SEWER LINE
UNDERGROUND ELECTRIC
WATER LINE
OVERHEAD ELECTRIC
PRODUCT LINE
MONITORING WELL
SI SOIL BORING LOCATION
SI SOIL BORING NOT ADVANCED
UST CLOSURE SAMPLE LOCATION
POWER POLE
SITE LAMP
ELECTRIC BOX
ELECTRIC PANEL
ELECTRIC METER
ELECTRIC SIGN
ELECTRIC TRANSFORMER
GAS METER
SANITARY GREASE TRAP
SANITARY SEWER CLEANOUT
WATER METER
WATER RISER
WATER VALVE
P
OE
FOR:
CHECKED BY:DRAWN BY:JOB NUMBER:APPROVED BY:DATE:
FIGURE:
1SITE MAP
ASAACCL203724146 2/28/2025
7-ELEVEN No. 47151
1344 FT UNION BLVD
COTTONWOOD HEIGHTS, UTAH 84121
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SI - SUBSURFACE INVESTIGATION
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Subsurface Investigation Report – 7-Eleven No. 47151
Facility ID 4000775, Release Site OLK
1344 Fort Union Boulevard, Cottonwood Heights, Utah
Tables
Project Number: 203724146

TABLES
SS-1 8 06/26/24 <0.00100 0.00264 0.00620 <0.00100 0.00620 <00.00500 <0.500 <40.0
SS-2 8 06/26/24 <0.00100 0.00206 <0.00500 <0.00100 <0.00300 <00.00500 <0.500 <4.00
SS-3 6 06/26/24 <0.00100 <0.00100 <0.00500 <0.00100 <0.00300 <00.00500 <0.500 8.54
SS-4 4 06/26/24 <0.00100 0.00216 0.0105 <0.00100 0.00320 <00.00500 <0.500 <4.00
SS-5 4 06/26/24 <0.00100 0.00184 <0.00500 <0.00100 0.00342 <0.00500 <0.500 <4.00
SS-6 5 06/27/24 <0.0250 <0.0250 <0.125 <0.0250 <0.0750 <0.125 <12.5 <4.00
SS-7 4 06/27/24 <0.00100 0.00226 <0.00500 <0.00100 <0.00300 <0.00500 <0.500 <4.00
SS-9 3 06/26/24 <0.00100 0.00143 <0.00500 <0.00100 <0.00300 <0.00500 <0.500 <4.00
MWOLK-3-2 2 01/16/25 <0.00129 <0.00129 <0.00643 <0.00322 <0.00836 <0.0161 <0.110 <4.38
MWOLK-3-9 9 01/16/25 <0.0114 <0.0114 <0.0570 <0.0285 <0.0741 <0.143 15.7 <45.7
MWOLK-3-15 15 01/16/25 <0.00194 <0.00194 <0.00972 <0.00486 <0.0126 <0.0243 <0.131 <5.26
0.3 0.2 9 5 142 51 150 150
0.3 0.9 25 23 142 51 1,500 1,500
All concentrations are listed in units of milligrams per kilogram (mg/Kg).
Explanation of Abbreviations:
bgs = below ground surface
MTBE = methyl tertiary butyl ether
TPH-GRO = gasoline-range total petroleum hydrocarbons
TPH-DRO = diesel-range total petroleum hydrocarbons
UDEQ = Utah Department of Environmental Quality
DERR = Department of Environmental Response and Remediation
ISL = Initial Screening Level
TSL = Tier 1 Screening Level
< = analyte not detected above the specified laboratory reporting limit
bold = analyte detected above the specified laboratory reporting limit
bold = analytical result exceeds the specified UDEQ DERR ISL
bold = analytical result exceeds the specified UDEQ DERR ISL and TSL
TPH-DRO
Table 1
Soil Analytical Results
7-Eleven Store No. 47151
1344 Fort Union Boulevard
Cottonwood Heights, Utah
Benzene TPH-GRO
UDEQ DERR TSL
UDEQ DERR ISL
MTBESample
Location
Date
Sampled
Depth
(feet bgs)
UST Closure Sample Results
Subsurface Investigation Sample Results
NaphthaleneTotal XylenesEthylbenzeneToluene
fnl_47151_tables_sir.xlsx Soil 1 of 1 Stantec Consulting Services Inc.
GW-1 8 06/26/24 <0.00100 0.505 1.74 0.113 1.08 0.00767 6.46 1.35
GW-2 8 06/26/24 <0.00100 0.290 1.01 0.0775 0.935 0.00908 4.88 1.58
MWOLK-1 9 01/16/25 <0.00100 <0.00100 <0.00100 <0.00100 <0.00300 <0.00500 <0.100 0.199 B
MWOLK-2N 10 01/16/25 <0.00200 <0.00200 <0.00200 <0.00200 <0.00600 <0.0100
C3 <0.216 --
MWOLK-2S 10 01/16/25 <0.00100 <0.00100 <0.00100 <0.00100 <0.00300 <0.00500 <0.100 0.974
MWOLK-3 7.78 01/16/25 <0.00100 <0.00100 <0.00100 <0.00100 <0.00300 <0.00500 0.503 0.189
B
DUP-1 (MWOLK-3) 7.78 01/16/25 <0.00100 <0.00100 <0.00100 <0.00100 <0.00300 <0.00500
1.02 0.351 B
RPD (%)-- -- -- -- --------68 60
0.2 0.005 1.0 0.7 10.0 0.7 1.0
0.2 0.3 3.0 4.00 10.0 0.7 10
All concentrations are listed in units of milligrams per liter (mg/L).
Explanation of Abbreviations:
MTBE = methyl tertiary butyl ether
TPH-GRO = gasoline-range total petroleum hydrocarbons
UDEQ = Utah Department of Environmental Quality
DERR = Department of Environmental Response and Remediation
ISL = Initial Screening Level
TSL = Tier 1 Screening Level
RPD = relative percent difference
-- = no data
<= analyte not detected above the specified laboratory reporting limit
bold = analyte detected above the specified laboratory reporting limit
bold = analytical result exceeds the specified UDEQ DERR ISL
bold = analytical result exceeds the specified UDEQ DERR ISL and TSL
B = The same analyte is found in the associated blank.
C3 = The reported concentration is an estimate. The continuing calibration standard associated with this data responded low.
Method sensitivity check is acceptable.
1.0
10
TPH-GRO
Table 2
Groundwater Analytical Results
7-Eleven Store No. 47151
1344 Fort Union Boulevard
Cottonwood Heights, Utah
Naphthalene TPH-DRO
UDEQ DERR TSL
Toluene Ethylbenzene Total Xylenes
UDEQ DERR ISL
Sample
Location
Depth
(feet bgs)
Date
Sampled MTBE Benzene
UST Closure Sample Results
Subsurface Investigation Sample Results
fnl_47151_tables_sir.xlsx GW 1 of 1 Stantec Consulting Services Inc.
Subsurface Investigation Report – 7-Eleven No. 47151
Facility ID 4000775, Release Site OLK
1344 Fort Union Boulevard, Cottonwood Heights, Utah

Boring Logs
Project Number: 203724146

APPENDIX A
BORING LOGS
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
SW, grey/black, dry, road base, 50% sand, 50%
gravel, sampled at 2 feet
(slight odor)
SP, wet to very wet, poor recovery, sampled at 9 feet
(strong odor, capillary fringe)
CL, wet, tan, medium plasticity, 60% clay, 40% silt,
sampled at 15 feet
(significant staining at top of layer, slight odor)
Flush well
vault
Bentonite
2 in. dia.
Sch. 40
PVC casing
20/40 Silica sand
2 in. dia.
Sch. 40
PVC .010
slot screen
BOREHOLE ID: MWWOLK-3 BOREHOLE ANGLE: 90 degrees
Depth (ft.) Lithological Graphic Lithological Description Well Construction
Subsurface Investigation Report – 7-Eleven No. 47151
Facility ID 4000775, Release Site OLK
1344 Fort Union Boulevard, Cottonwood Heights, Utah

Laboratory Analytical Reports and
Chain of Custody Documentation
Project Number: 203724146

APPENDIX B
LABORATORY ANALYTICAL REPORTS AND
CHAIN OF CUSTODY DOCUMENTATION
ANALYTICAL REPORT
January 28, 2025
711 Stantec - Salt Lake City, UT
Sample Delivery Group:L1818673
Samples Received:01/18/2025
Project Number:203724146
Description:7-11 #47151 Cottonwood Heights, UT
Site:47151
Report To:Anna Skinner
2890 E Cottonwood Pkwy
Suite 300
Salt Lake City, UT 84121
Entire Report Reviewed By:
January 28, 2025
[Preliminary Report]
Marty Edwards III
Project Manager
Results relate only to the items tested or calibrated and are reported as rounded values. This test report shall not be
reproduced, except in full, without written approval of the laboratory. Where applicable, sampling conducted by Pace
Analytical National is performed per guidance provided in laboratory standard operating procedures ENV-SOP-MTJL-0067 and
ENV-SOP-MTJL-0068. Where sampling conducted by the customer, results relate to the accuracy of the information provided,
and as the samples are received.
Pace Analytical National
12065 Lebanon Rd Mount Juliet, TN 37122 615-758-5858 800-767-5859 mydata.pacelabs.com
1 Cp
2 Tc
3 Ss
4 Cn
5 Sr
6 Qc
7 Gl
8 Al
9 Sc
ACCOUNT:PROJECT:SDG:DATE/TIME:PAGE:
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January 29, 2025
Marty Edwards III
Project Manager
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TABLE OF CONTENTS
Cp: Cover Page 1
Tc: Table of Contents 2
Ss: Sample Summary 3
Cn: Case Narrative 5
Sr: Sample Results 6
MWOLK-3-2 L1818673-01 6
MWOLK-3-9 L1818673-02 7
MWOLK-3-15 L1818673-03 8
TB L1818673-04 9
MWOLK-2N L1818673-05 10
MWOLK-2S L1818673-06 11
MWOLK-1 L1818673-07 12
MWOLK-3 L1818673-08 13
DUP-1 L1818673-09 14
Qc: Quality Control Summary 15
Total Solids by Method 2540 G-2011 15
Volatile Organic Compounds (GC) by Method 8015D/GRO 16
Volatile Organic Compounds (GC/MS) by Method 8260B 20
Volatile Organic Compounds (GC/MS) by Method 8260B/8260B/OA1 22
Semi-Volatile Organic Compounds (GC) by Method 8015 23
Semi-Volatile Organic Compounds (GC) by Method 8015D 24
Gl: Glossary of Terms 25
Al: Accreditations & Locations 26
Sc: Sample Chain of Custody 27
1 Cp
2 Tc
3 Ss
4 Cn
5 Sr
6 Qc
7 Gl
8 Al
9 Sc
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SAMPLE SUMMARY
Collected by Collected date/time Received date/time
MWOLK-3-2 L1818673-01 Solid Andrew Huffman 01/16/25 12:50 01/18/25 08:45
Method Batch Dilution Preparation Analysis Analyst Location
date/time date/time
Total Solids by Method 2540 G-2011 WG2436716 1 01/21/25 10:04 01/21/25 10:13 MT Mt. Juliet, TN
Volatile Organic Compounds (GC) by Method 8015D/GRO WG2438802 1 01/22/25 20:36 01/23/25 23:08 DWR Mt. Juliet, TN
Volatile Organic Compounds (GC/MS) by Method 8260B WG2438187 1 01/22/25 20:36 01/22/25 23:43 JHH Mt. Juliet, TN
Semi-Volatile Organic Compounds (GC) by Method 8015 WG2438907 1 01/24/25 07:11 01/24/25 12:28 KDB Mt. Juliet, TN
Collected by Collected date/time Received date/time
MWOLK-3-9 L1818673-02 Solid Andrew Huffman 01/16/25 13:00 01/18/25 08:45
Method Batch Dilution Preparation Analysis Analyst Location
date/time date/time
Total Solids by Method 2540 G-2011 WG2436716 1 01/21/25 10:04 01/21/25 10:13 MT Mt. Juliet, TN
Volatile Organic Compounds (GC) by Method 8015D/GRO WG2438868 100 01/22/25 20:36 01/24/25 09:15 ACG Mt. Juliet, TN
Volatile Organic Compounds (GC/MS) by Method 8260B WG2438187 8 01/22/25 20:36 01/23/25 00:02 JHH Mt. Juliet, TN
Semi-Volatile Organic Compounds (GC) by Method 8015 WG2438907 10 01/24/25 07:11 01/24/25 14:48 KDB Mt. Juliet, TN
Collected by Collected date/time Received date/time
MWOLK-3-15 L1818673-03 Solid Andrew Huffman 01/16/25 11:30 01/18/25 08:45
Method Batch Dilution Preparation Analysis Analyst Location
date/time date/time
Total Solids by Method 2540 G-2011 WG2436716 1 01/21/25 10:04 01/21/25 10:13 MT Mt. Juliet, TN
Volatile Organic Compounds (GC) by Method 8015D/GRO WG2438802 1 01/22/25 20:36 01/24/25 00:18 DWR Mt. Juliet, TN
Volatile Organic Compounds (GC/MS) by Method 8260B WG2438187 1 01/22/25 20:36 01/23/25 00:21 JHH Mt. Juliet, TN
Semi-Volatile Organic Compounds (GC) by Method 8015 WG2438907 1 01/24/25 07:11 01/24/25 12:15 KDB Mt. Juliet, TN
Collected by Collected date/time Received date/time
TB L1818673-04 GW Andrew Huffman 01/16/25 00:00 01/18/25 08:45
Method Batch Dilution Preparation Analysis Analyst Location
date/time date/time
Volatile Organic Compounds (GC/MS) by Method 8260B/8260B/OA1 WG2441500 1 01/23/25 23:52 01/23/25 23:52 JHH Mt. Juliet, TN
Collected by Collected date/time Received date/time
MWOLK-2N L1818673-05 GW Andrew Huffman 01/16/25 00:00 01/18/25 08:45
Method Batch Dilution Preparation Analysis Analyst Location
date/time date/time
Volatile Organic Compounds (GC/MS) by Method 8260B/8260B/OA1 WG2441500 2 01/24/25 05:46 01/24/25 05:46 JHH Mt. Juliet, TN
Collected by Collected date/time Received date/time
MWOLK-2S L1818673-06 GW Andrew Huffman 01/16/25 14:20 01/18/25 08:45
Method Batch Dilution Preparation Analysis Analyst Location
date/time date/time
Volatile Organic Compounds (GC) by Method 8015D/GRO WG2439626 1 01/25/25 04:37 01/25/25 04:37 ADM Mt. Juliet, TN
Volatile Organic Compounds (GC/MS) by Method 8260B WG2436523 1 01/20/25 17:26 01/20/25 17:26 DYW Mt. Juliet, TN
Semi-Volatile Organic Compounds (GC) by Method 8015D WG2438146 1 01/23/25 07:04 01/27/25 18:27 DMG Mt. Juliet, TN
Collected by Collected date/time Received date/time
MWOLK-1 L1818673-07 GW Andrew Huffman 01/16/25 12:00 01/18/25 08:45
Method Batch Dilution Preparation Analysis Analyst Location
date/time date/time
Volatile Organic Compounds (GC) by Method 8015D/GRO WG2437380 1 01/21/25 23:53 01/21/25 23:53 CDD Mt. Juliet, TN
Volatile Organic Compounds (GC/MS) by Method 8260B WG2436523 1 01/20/25 17:48 01/20/25 17:48 DYW Mt. Juliet, TN
Semi-Volatile Organic Compounds (GC) by Method 8015D WG2438146 1 01/23/25 07:04 01/27/25 17:08 DMG Mt. Juliet, TN
1 Cp
2 Tc
3 Ss
4 Cn
5 Sr
6 Qc
7 Gl
8 Al
9 Sc
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SAMPLE SUMMARY
Collected by Collected date/time Received date/time
MWOLK-3 L1818673-08 GW Andrew Huffman 01/16/25 16:15 01/18/25 08:45
Method Batch Dilution Preparation Analysis Analyst Location
date/time date/time
Volatile Organic Compounds (GC) by Method 8015D/GRO WG2437380 1 01/22/25 00:15 01/22/25 00:15 CDD Mt. Juliet, TN
Volatile Organic Compounds (GC/MS) by Method 8260B WG2436523 1 01/20/25 18:09 01/20/25 18:09 DYW Mt. Juliet, TN
Semi-Volatile Organic Compounds (GC) by Method 8015D WG2438146 1 01/23/25 07:04 01/25/25 15:05 MAA Mt. Juliet, TN
Collected by Collected date/time Received date/time
DUP-1 L1818673-09 GW Andrew Huffman 01/16/25 00:00 01/18/25 08:45
Method Batch Dilution Preparation Analysis Analyst Location
date/time date/time
Volatile Organic Compounds (GC) by Method 8015D/GRO WG2437380 1 01/22/25 00:37 01/22/25 00:37 CDD Mt. Juliet, TN
Volatile Organic Compounds (GC/MS) by Method 8260B WG2436523 1 01/20/25 18:30 01/20/25 18:30 DYW Mt. Juliet, TN
Semi-Volatile Organic Compounds (GC) by Method 8015D WG2438146 1 01/23/25 07:04 01/25/25 15:26 MAA Mt. Juliet, TN
1 Cp
2 Tc
3 Ss
4 Cn
5 Sr
6 Qc
7 Gl
8 Al
9 Sc
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CASE NARRATIVE
All sample aliquots were received at the correct temperature, in the proper containers, with the
appropriate preservatives, and within method specified holding times, unless qualified or notated within
the report. Where applicable, all MDL (LOD) and RDL (LOQ) values reported for environmental samples
have been corrected for the dilution factor used in the analysis. All Method and Batch Quality Control
are within established criteria except where addressed in this case narrative, a non-conformance form
or properly qualified within the sample results. By my digital signature below, I affirm to the best of my
knowledge, all problems/anomalies observed by the laboratory as having the potential to affect the
quality of the data have been identified by the laboratory, and no information or data have been
knowingly withheld that would affect the quality of the data.
[Preliminary Report]
Marty Edwards III
Project Manager
Sample Delivery Group (SDG) Narrative
pH outside of method requirement.
Lab Sample ID Project Sample ID Method
L1818673-06 MWOLK-2S 8015D/GRO
Analyzed from headspace vial.
Lab Sample ID Project Sample ID Method
L1818673-06 MWOLK-2S 8015D/GRO
1 Cp
2 Tc
3 Ss
4 Cn
5 Sr
6 Qc
7 Gl
8 Al
9 Sc
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Marty Edwards III
Project Manager
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SAMPLE RESULTS - 01
L1818673
MWOLK-3-2
Collected date/time: 01/16/25 12:50
Total Solids by Method 2540 G-2011
Result Qualifier Dilution Analysis Batch
Analyte %date / time
Total Solids 91.3 1 01/21/2025 10:13 WG2436716
Volatile Organic Compounds (GC) by Method 8015D/GRO
Result (dry)Qualifier RDL (dry)Dilution Analysis Batch
Analyte mg/kg mg/kg date / time
TPH (GC/FID) Low Fraction ND 0.110 1 01/23/2025 23:08 WG2438802
(S) a,a,a-Trifluorotoluene(FID)93.5 77.0-120 01/23/2025 23:08 WG2438802
Volatile Organic Compounds (GC/MS) by Method 8260B
Result (dry)Qualifier RDL (dry)Dilution Analysis Batch
Analyte mg/kg mg/kg date / time
Benzene ND 0.00129 1 01/22/2025 23:43 WG2438187
Toluene ND 0.00643 1 01/22/2025 23:43 WG2438187
Ethylbenzene ND 0.00322 1 01/22/2025 23:43 WG2438187
Total Xylenes ND 0.00836 1 01/22/2025 23:43 WG2438187
Methyl tert-butyl ether ND 0.00129 1 01/22/2025 23:43 WG2438187
Naphthalene ND 0.0161 1 01/22/2025 23:43 WG2438187
(S) Toluene-d8 93.4 75.0-131 01/22/2025 23:43 WG2438187
(S) 4-Bromofluorobenzene 110 67.0-138 01/22/2025 23:43 WG2438187
(S) 1,2-Dichloroethane-d4 96.3 70.0-130 01/22/2025 23:43 WG2438187
Semi-Volatile Organic Compounds (GC) by Method 8015
Result (dry)Qualifier RDL (dry)Dilution Analysis Batch
Analyte mg/kg mg/kg date / time
TPH (GC/FID) High Fraction ND 4.38 1 01/24/2025 12:28 WG2438907
(S) o-Terphenyl 72.7 18.0-148 01/24/2025 12:28 WG2438907
1 Cp
2 Tc
3 Ss
4 Cn
5 Sr
6 Qc
7 Gl
8 Al
9 Sc
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SAMPLE RESULTS - 02
L1818673
MWOLK-3-9
Collected date/time: 01/16/25 13:00
Total Solids by Method 2540 G-2011
Result Qualifier Dilution Analysis Batch
Analyte %date / time
Total Solids 87.6 1 01/21/2025 10:13 WG2436716
Volatile Organic Compounds (GC) by Method 8015D/GRO
Result (dry)Qualifier RDL (dry)Dilution Analysis Batch
Analyte mg/kg mg/kg date / time
TPH (GC/FID) Low Fraction 15.7 14.3 100 01/24/2025 09:15 WG2438868
(S) a,a,a-Trifluorotoluene(FID)99.7 77.0-120 01/24/2025 09:15 WG2438868
Volatile Organic Compounds (GC/MS) by Method 8260B
Result (dry)Qualifier RDL (dry)Dilution Analysis Batch
Analyte mg/kg mg/kg date / time
Benzene ND 0.0114 8 01/23/2025 00:02 WG2438187
Toluene ND 0.0570 8 01/23/2025 00:02 WG2438187
Ethylbenzene ND 0.0285 8 01/23/2025 00:02 WG2438187
Total Xylenes ND 0.0741 8 01/23/2025 00:02 WG2438187
Methyl tert-butyl ether ND 0.0114 8 01/23/2025 00:02 WG2438187
Naphthalene ND 0.143 8 01/23/2025 00:02 WG2438187
(S) Toluene-d8 95.8 75.0-131 01/23/2025 00:02 WG2438187
(S) 4-Bromofluorobenzene 109 67.0-138 01/23/2025 00:02 WG2438187
(S) 1,2-Dichloroethane-d4 90.4 70.0-130 01/23/2025 00:02 WG2438187
Semi-Volatile Organic Compounds (GC) by Method 8015
Result (dry)Qualifier RDL (dry)Dilution Analysis Batch
Analyte mg/kg mg/kg date / time
TPH (GC/FID) High Fraction ND 45.7 10 01/24/2025 14:48 WG2438907
(S) o-Terphenyl 67.9 18.0-148 01/24/2025 14:48 WG2438907
Sample Narrative:
L1818673-02 WG2438907: Cannot run at lower dilution due to viscosity of extract
1 Cp
2 Tc
3 Ss
4 Cn
5 Sr
6 Qc
7 Gl
8 Al
9 Sc
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SAMPLE RESULTS - 03
L1818673
MWOLK-3-15
Collected date/time: 01/16/25 11:30
Total Solids by Method 2540 G-2011
Result Qualifier Dilution Analysis Batch
Analyte %date / time
Total Solids 76.1 1 01/21/2025 10:13 WG2436716
Volatile Organic Compounds (GC) by Method 8015D/GRO
Result (dry)Qualifier RDL (dry)Dilution Analysis Batch
Analyte mg/kg mg/kg date / time
TPH (GC/FID) Low Fraction ND 0.131 1 01/24/2025 00:18 WG2438802
(S) a,a,a-Trifluorotoluene(FID)93.8 77.0-120 01/24/2025 00:18 WG2438802
Volatile Organic Compounds (GC/MS) by Method 8260B
Result (dry)Qualifier RDL (dry)Dilution Analysis Batch
Analyte mg/kg mg/kg date / time
Benzene ND 0.00194 1 01/23/2025 00:21 WG2438187
Toluene ND 0.00972 1 01/23/2025 00:21 WG2438187
Ethylbenzene ND 0.00486 1 01/23/2025 00:21 WG2438187
Total Xylenes ND 0.0126 1 01/23/2025 00:21 WG2438187
Methyl tert-butyl ether ND 0.00194 1 01/23/2025 00:21 WG2438187
Naphthalene ND 0.0243 1 01/23/2025 00:21 WG2438187
(S) Toluene-d8 95.3 75.0-131 01/23/2025 00:21 WG2438187
(S) 4-Bromofluorobenzene 105 67.0-138 01/23/2025 00:21 WG2438187
(S) 1,2-Dichloroethane-d4 90.3 70.0-130 01/23/2025 00:21 WG2438187
Semi-Volatile Organic Compounds (GC) by Method 8015
Result (dry)Qualifier RDL (dry)Dilution Analysis Batch
Analyte mg/kg mg/kg date / time
TPH (GC/FID) High Fraction ND 5.26 1 01/24/2025 12:15 WG2438907
(S) o-Terphenyl 59.2 18.0-148 01/24/2025 12:15 WG2438907
1 Cp
2 Tc
3 Ss
4 Cn
5 Sr
6 Qc
7 Gl
8 Al
9 Sc
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SAMPLE RESULTS - 04
L1818673
TB
Collected date/time: 01/16/25 00:00
Volatile Organic Compounds (GC/MS) by Method 8260B/8260B/OA1
Result Qualifier RDL Dilution Analysis Batch
Analyte mg/l mg/l date / time
TPH (GC/MS) Low Fraction ND 0.500 1 01/23/2025 23:52 WG2441500
Benzene ND 0.00100 1 01/23/2025 23:52 WG2441500
Toluene ND 0.00100 1 01/23/2025 23:52 WG2441500
Ethylbenzene ND 0.00100 1 01/23/2025 23:52 WG2441500
Xylenes, Total ND 0.00300 1 01/23/2025 23:52 WG2441500
Methyl tert-butyl ether ND 0.00100 1 01/23/2025 23:52 WG2441500
Naphthalene ND C3 0.00500 1 01/23/2025 23:52 WG2441500
(S) Toluene-d8 92.3 80.0-120 01/23/2025 23:52 WG2441500
(S) 4-Bromofluorobenzene 102 77.0-126 01/23/2025 23:52 WG2441500
(S) 1,2-Dichloroethane-d4 100 70.0-130 01/23/2025 23:52 WG2441500
1 Cp
2 Tc
3 Ss
4 Cn
5 Sr
6 Qc
7 Gl
8 Al
9 Sc
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SAMPLE RESULTS - 05
L1818673
MWOLK-2N
Collected date/time: 01/16/25 00:00
Volatile Organic Compounds (GC/MS) by Method 8260B/8260B/OA1
Result Qualifier RDL Dilution Analysis Batch
Analyte mg/l mg/l date / time
TPH (GC/MS) Low Fraction ND 0.216 2 01/24/2025 05:46 WG2441500
Benzene ND 0.00200 2 01/24/2025 05:46 WG2441500
Toluene ND 0.00200 2 01/24/2025 05:46 WG2441500
Ethylbenzene ND 0.00200 2 01/24/2025 05:46 WG2441500
Xylenes, Total ND 0.00600 2 01/24/2025 05:46 WG2441500
Methyl tert-butyl ether ND 0.00200 2 01/24/2025 05:46 WG2441500
Naphthalene ND C3 0.0100 2 01/24/2025 05:46 WG2441500
(S) Toluene-d8 92.9 80.0-120 01/24/2025 05:46 WG2441500
(S) 4-Bromofluorobenzene 102 77.0-126 01/24/2025 05:46 WG2441500
(S) 1,2-Dichloroethane-d4 101 70.0-130 01/24/2025 05:46 WG2441500
Sample Narrative:
L1818673-05 WG2441500: Dilution due to sediment. TPH (GC/MS) Low Fraction was reported to the MDL.
1 Cp
2 Tc
3 Ss
4 Cn
5 Sr
6 Qc
7 Gl
8 Al
9 Sc
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SAMPLE RESULTS - 06
L1818673
MWOLK-2S
Collected date/time: 01/16/25 14:20
Volatile Organic Compounds (GC) by Method 8015D/GRO
Result Qualifier RDL Dilution Analysis Batch
Analyte mg/l mg/l date / time
TPH (GC/FID) Low Fraction ND 0.100 1 01/25/2025 04:37 WG2439626
(S) a,a,a-Trifluorotoluene(FID)104 78.0-120 01/25/2025 04:37 WG2439626
Volatile Organic Compounds (GC/MS) by Method 8260B/8260B/OA1
Result Qualifier RDL Dilution Analysis Batch
Analyte mg/l mg/l date / time
Benzene ND 0.00100 1 01/20/2025 17:26 WG2436523
Toluene ND 0.00100 1 01/20/2025 17:26 WG2436523
Ethylbenzene ND 0.00100 1 01/20/2025 17:26 WG2436523
Total Xylenes ND 0.00300 1 01/20/2025 17:26 WG2436523
Methyl tert-butyl ether ND 0.00100 1 01/20/2025 17:26 WG2436523
Naphthalene ND 0.00500 1 01/20/2025 17:26 WG2436523
(S) Toluene-d8 99.9 80.0-120 01/20/2025 17:26 WG2436523
(S) 4-Bromofluorobenzene 93.8 77.0-126 01/20/2025 17:26 WG2436523
(S) 1,2-Dichloroethane-d4 116 70.0-130 01/20/2025 17:26 WG2436523
Semi-Volatile Organic Compounds (GC) by Method 8015D
Result Qualifier RDL Dilution Analysis Batch
Analyte mg/l mg/l date / time
TPH (GC/FID) High Fraction 0.974 0.100 1 01/27/2025 18:27 WG2438146
(S) o-Terphenyl 56.0 31.0-160 01/27/2025 18:27 WG2438146
1 Cp
2 Tc
3 Ss
4 Cn
5 Sr
6 Qc
7 Gl
8 Al
9 Sc
ACCOUNT:PROJECT:SDG:DATE/TIME:PAGE:
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ACCOUNT:PROJECT:SDG:DATE/TIME:PAGE:
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SAMPLE RESULTS - 07
L1818673
MWOLK-1
Collected date/time: 01/16/25 12:00
Volatile Organic Compounds (GC) by Method 8015D/GRO
Result Qualifier RDL Dilution Analysis Batch
Analyte mg/l mg/l date / time
TPH (GC/FID) Low Fraction ND 0.100 1 01/21/2025 23:53 WG2437380
(S) a,a,a-Trifluorotoluene(FID)107 78.0-120 01/21/2025 23:53 WG2437380
Volatile Organic Compounds (GC/MS) by Method 8260B/8260B/OA1
Result Qualifier RDL Dilution Analysis Batch
Analyte mg/l mg/l date / time
Benzene ND 0.00100 1 01/20/2025 17:48 WG2436523
Toluene ND 0.00100 1 01/20/2025 17:48 WG2436523
Ethylbenzene ND 0.00100 1 01/20/2025 17:48 WG2436523
Total Xylenes ND 0.00300 1 01/20/2025 17:48 WG2436523
Methyl tert-butyl ether ND 0.00100 1 01/20/2025 17:48 WG2436523
Naphthalene ND 0.00500 1 01/20/2025 17:48 WG2436523
(S) Toluene-d8 101 80.0-120 01/20/2025 17:48 WG2436523
(S) 4-Bromofluorobenzene 96.4 77.0-126 01/20/2025 17:48 WG2436523
(S) 1,2-Dichloroethane-d4 116 70.0-130 01/20/2025 17:48 WG2436523
Semi-Volatile Organic Compounds (GC) by Method 8015D
Result Qualifier RDL Dilution Analysis Batch
Analyte mg/l mg/l date / time
TPH (GC/FID) High Fraction 0.199 B 0.100 1 01/27/2025 17:08 WG2438146
(S) o-Terphenyl 56.6 31.0-160 01/27/2025 17:08 WG2438146
1 Cp
2 Tc
3 Ss
4 Cn
5 Sr
6 Qc
7 Gl
8 Al
9 Sc
ACCOUNT:PROJECT:SDG:DATE/TIME:PAGE:
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ACCOUNT:PROJECT:SDG:DATE/TIME:PAGE:
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SAMPLE RESULTS - 08
L1818673
MWOLK-3
Collected date/time: 01/16/25 16:15
Volatile Organic Compounds (GC) by Method 8015D/GRO
Result Qualifier RDL Dilution Analysis Batch
Analyte mg/l mg/l date / time
TPH (GC/FID) Low Fraction 0.503 0.100 1 01/22/2025 00:15 WG2437380
(S) a,a,a-Trifluorotoluene(FID)104 78.0-120 01/22/2025 00:15 WG2437380
Volatile Organic Compounds (GC/MS) by Method 8260B/8260B/OA1
Result Qualifier RDL Dilution Analysis Batch
Analyte mg/l mg/l date / time
Benzene ND 0.00100 1 01/20/2025 18:09 WG2436523
Toluene ND 0.00100 1 01/20/2025 18:09 WG2436523
Ethylbenzene ND 0.00100 1 01/20/2025 18:09 WG2436523
Total Xylenes ND 0.00300 1 01/20/2025 18:09 WG2436523
Methyl tert-butyl ether ND 0.00100 1 01/20/2025 18:09 WG2436523
Naphthalene ND 0.00500 1 01/20/2025 18:09 WG2436523
(S) Toluene-d8 96.8 80.0-120 01/20/2025 18:09 WG2436523
(S) 4-Bromofluorobenzene 95.4 77.0-126 01/20/2025 18:09 WG2436523
(S) 1,2-Dichloroethane-d4 119 70.0-130 01/20/2025 18:09 WG2436523
Semi-Volatile Organic Compounds (GC) by Method 8015D
Result Qualifier RDL Dilution Analysis Batch
Analyte mg/l mg/l date / time
TPH (GC/FID) High Fraction 0.189 B 0.100 1 01/25/2025 15:05 WG2438146
(S) o-Terphenyl 84.2 31.0-160 01/25/2025 15:05 WG2438146
1 Cp
2 Tc
3 Ss
4 Cn
5 Sr
6 Qc
7 Gl
8 Al
9 Sc
ACCOUNT:PROJECT:SDG:DATE/TIME:PAGE:
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ACCOUNT:PROJECT:SDG:DATE/TIME:PAGE:
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SAMPLE RESULTS - 09
L1818673
DUP-1
Collected date/time: 01/16/25 00:00
Volatile Organic Compounds (GC) by Method 8015D/GRO
Result Qualifier RDL Dilution Analysis Batch
Analyte mg/l mg/l date / time
TPH (GC/FID) Low Fraction 1.02 0.100 1 01/22/2025 00:37 WG2437380
(S) a,a,a-Trifluorotoluene(FID)101 78.0-120 01/22/2025 00:37 WG2437380
Volatile Organic Compounds (GC/MS) by Method 8260B/8260B/OA1
Result Qualifier RDL Dilution Analysis Batch
Analyte mg/l mg/l date / time
Benzene ND 0.00100 1 01/20/2025 18:30 WG2436523
Toluene ND 0.00100 1 01/20/2025 18:30 WG2436523
Ethylbenzene ND 0.00100 1 01/20/2025 18:30 WG2436523
Total Xylenes ND 0.00300 1 01/20/2025 18:30 WG2436523
Methyl tert-butyl ether ND 0.00100 1 01/20/2025 18:30 WG2436523
Naphthalene ND 0.00500 1 01/20/2025 18:30 WG2436523
(S) Toluene-d8 98.3 80.0-120 01/20/2025 18:30 WG2436523
(S) 4-Bromofluorobenzene 97.4 77.0-126 01/20/2025 18:30 WG2436523
(S) 1,2-Dichloroethane-d4 116 70.0-130 01/20/2025 18:30 WG2436523
Semi-Volatile Organic Compounds (GC) by Method 8015D
Result Qualifier RDL Dilution Analysis Batch
Analyte mg/l mg/l date / time
TPH (GC/FID) High Fraction 0.351 B 0.100 1 01/25/2025 15:26 WG2438146
(S) o-Terphenyl 92.4 31.0-160 01/25/2025 15:26 WG2438146
1 Cp
2 Tc
3 Ss
4 Cn
5 Sr
6 Qc
7 Gl
8 Al
9 Sc
ACCOUNT:PROJECT:SDG:DATE/TIME:PAGE:
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711 Stantec - Salt Lake City, UT 203724146 L1818673 01/29/25 10:53 14 of 28
QUALITY CONTROL SUMMARYWG2436716
Total Solids by Method 2540 G-2011 L1818673-01,02,03
Method Blank (MB)
(MB) R4168959-1 01/21/25 10:13
MB Result MB Qualifier MB MDL MB RDL
Analyte %%%
Total Solids 0.000
L1818681-01 Original Sample (OS) • Duplicate (DUP)
(OS) L1818681-01 01/21/25 10:13 • (DUP) R4168959-3 01/21/25 10:13
Original Result DUP Result Dilution DUP RPD DUP Qualifier DUP RPD
Limits
Analyte %%%%
Total Solids 77.2 76.9 1 0.352 10
Laboratory Control Sample (LCS)
(LCS) R4168959-2 01/21/25 10:13
Spike Amount LCS Result LCS Rec.Rec. Limits LCS Qualifier
Analyte %%%%
Total Solids 50.0 50.0 100 90.0-110
1 Cp
2 Tc
3 Ss
4 Cn
5 Sr
6 Qc
7 Gl
8 Al
9 Sc
ACCOUNT:PROJECT:SDG:DATE/TIME:PAGE:
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ACCOUNT:PROJECT:SDG:DATE/TIME:PAGE:
711 Stantec - Salt Lake City, UT 203724146 L1818673 01/29/25 10:53 15 of 28
QUALITY CONTROL SUMMARYWG2437380
Volatile Organic Compounds (GC) by Method 8015D/GRO L1818673-07,08,09
Method Blank (MB)
(MB) R4169185-2 01/21/25 21:24
MB Result MB Qualifier MB MDL MB RDL
Analyte mg/l mg/l mg/l
TPH (GC/FID) Low Fraction U 0.0314 0.100
(S)
a,a,a-Trifluorotoluene(FID)107 78.0-120
Laboratory Control Sample (LCS)
(LCS) R4169185-1 01/21/25 20:19
Spike Amount LCS Result LCS Rec.Rec. Limits LCS Qualifier
Analyte mg/l mg/l %%
TPH (GC/FID) Low Fraction 5.00 5.26 105 72.0-127
(S)
a,a,a-Trifluorotoluene(FID) 110 78.0-120
1 Cp
2 Tc
3 Ss
4 Cn
5 Sr
6 Qc
7 Gl
8 Al
9 Sc
ACCOUNT:PROJECT:SDG:DATE/TIME:PAGE:
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ACCOUNT:PROJECT:SDG:DATE/TIME:PAGE:
711 Stantec - Salt Lake City, UT 203724146 L1818673 01/29/25 10:53 16 of 28
QUALITY CONTROL SUMMARYWG2439626
Volatile Organic Compounds (GC) by Method 8015D/GRO L1818673-06
Method Blank (MB)
(MB) R4170301-3 01/25/25 01:41
MB Result MB Qualifier MB MDL MB RDL
Analyte mg/l mg/l mg/l
TPH (GC/FID) Low Fraction 0.0419 J 0.0314 0.100
(S)
a,a,a-Trifluorotoluene(FID)103 78.0-120
Laboratory Control Sample (LCS) • Laboratory Control Sample Duplicate (LCSD)
(LCS) R4170301-1 01/25/25 00:26 • (LCSD) R4170301-2 01/25/25 00:57
Spike Amount LCS Result LCSD Result LCS Rec.LCSD Rec.Rec. Limits LCS Qualifier LCSD Qualifier RPD RPD Limits
Analyte mg/l mg/l mg/l %%%%%
TPH (GC/FID) Low Fraction 5.50 5.77 5.76 105 105 72.0-127 0.173 20
(S)
a,a,a-Trifluorotoluene(FID) 108 109 78.0-120
1 Cp
2 Tc
3 Ss
4 Cn
5 Sr
6 Qc
7 Gl
8 Al
9 Sc
ACCOUNT:PROJECT:SDG:DATE/TIME:PAGE:
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ACCOUNT:PROJECT:SDG:DATE/TIME:PAGE:
711 Stantec - Salt Lake City, UT 203724146 L1818673 01/29/25 10:53 17 of 28
QUALITY CONTROL SUMMARYWG2438802
Volatile Organic Compounds (GC) by Method 8015D/GRO L1818673-01,03
Method Blank (MB)
(MB) R4170145-3 01/23/25 20:53
MB Result MB Qualifier MB MDL MB RDL
Analyte mg/kg mg/kg mg/kg
TPH (GC/FID) Low Fraction 0.0372 J 0.0217 0.100
(S)
a,a,a-Trifluorotoluene(FID)94.8 77.0-120
Laboratory Control Sample (LCS)
(LCS) R4170145-1 01/23/25 18:58
Spike Amount LCS Result LCS Rec.Rec. Limits LCS Qualifier
Analyte mg/kg mg/kg %%
TPH (GC/FID) Low Fraction 5.00 4.96 99.2 72.0-127
(S)
a,a,a-Trifluorotoluene(FID) 97.1 77.0-120
1 Cp
2 Tc
3 Ss
4 Cn
5 Sr
6 Qc
7 Gl
8 Al
9 Sc
ACCOUNT:PROJECT:SDG:DATE/TIME:PAGE:
711 Stantec - Salt Lake City, UT 203724146 L1818673 01/28/25 19:03 18 of 28
ACCOUNT:PROJECT:SDG:DATE/TIME:PAGE:
711 Stantec - Salt Lake City, UT 203724146 L1818673 01/29/25 10:53 18 of 28
QUALITY CONTROL SUMMARYWG2438868
Volatile Organic Compounds (GC) by Method 8015D/GRO L1818673-02
Method Blank (MB)
(MB) R4170120-3 01/23/25 23:42
MB Result MB Qualifier MB MDL MB RDL
Analyte mg/kg mg/kg mg/kg
TPH (GC/FID) Low Fraction 0.697 J 0.543 2.50
(S)
a,a,a-Trifluorotoluene(FID)98.7 77.0-120
Laboratory Control Sample (LCS) • Laboratory Control Sample Duplicate (LCSD)
(LCS) R4170120-1 01/23/25 22:03 • (LCSD) R4170120-2 01/23/25 22:32
Spike Amount LCS Result LCSD Result LCS Rec.LCSD Rec.Rec. Limits LCS Qualifier LCSD Qualifier RPD RPD Limits
Analyte mg/kg mg/kg mg/kg %%%%%
TPH (GC/FID) Low Fraction 5.00 5.15 4.90 103 98.0 72.0-127 4.98 20
(S)
a,a,a-Trifluorotoluene(FID) 102 102 77.0-120
L1819446-06 Original Sample (OS) • Matrix Spike (MS) • Matrix Spike Duplicate (MSD)
(OS) L1819446-06 01/24/25 08:51 • (MS) R4170120-4 01/24/25 09:39 • (MSD) R4170120-5 01/24/25 10:02
Spike Amount Original Result MS Result MSD Result MS Rec.MSD Rec.Dilution Rec. Limits MS Qualifier MSD Qualifier RPD RPD Limits
Analyte mg/kg mg/kg mg/kg mg/kg %%%%%
TPH (GC/FID) Low Fraction 104 ND 91.5 91.9 87.4 87.8 25 10.0-151 0.436 28
(S)
a,a,a-Trifluorotoluene(FID) 101 101 77.0-120
1 Cp
2 Tc
3 Ss
4 Cn
5 Sr
6 Qc
7 Gl
8 Al
9 Sc
ACCOUNT:PROJECT:SDG:DATE/TIME:PAGE:
711 Stantec - Salt Lake City, UT 203724146 L1818673 01/28/25 19:03 19 of 28
ACCOUNT:PROJECT:SDG:DATE/TIME:PAGE:
711 Stantec - Salt Lake City, UT 203724146 L1818673 01/29/25 10:53 19 of 28
QUALITY CONTROL SUMMARYWG2436523
Volatile Organic Compounds (GC/MS) by Method 8260B L1818673-06,07,08,09
Method Blank (MB)
(MB) R4169268-3 01/20/25 12:18
MB Result MB Qualifier MB MDL MB RDL
Analyte mg/l mg/l mg/l
Benzene U 0.0000941 0.00100
Toluene U 0.000278 0.00100
Ethylbenzene U 0.000137 0.00100
Total Xylenes U 0.000174 0.00300
Methyl tert-butyl ether U 0.000101 0.00100
Naphthalene U 0.00100 0.00500
(S) Toluene-d8 101 80.0-120
(S) 4-Bromofluorobenzene 97.4 77.0-126
(S) 1,2-Dichloroethane-d4 115 70.0-130
Laboratory Control Sample (LCS) • Laboratory Control Sample Duplicate (LCSD)
(LCS) R4169268-1 01/20/25 11:14 • (LCSD) R4169268-2 01/20/25 11:35
Spike Amount LCS Result LCSD Result LCS Rec.LCSD Rec.Rec. Limits LCS Qualifier LCSD Qualifier RPD RPD Limits
Analyte mg/l mg/l mg/l %%%%%
Benzene 0.00500 0.00483 0.00460 96.6 92.0 70.0-123 4.88 20
Toluene 0.00500 0.00493 0.00470 98.6 94.0 79.0-120 4.78 20
Ethylbenzene 0.00500 0.00472 0.00442 94.4 88.4 79.0-123 6.56 20
Total Xylenes 0.0150 0.0143 0.0135 95.3 90.0 79.0-123 5.76 20
Methyl tert-butyl ether 0.00500 0.00483 0.00486 96.6 97.2 68.0-125 0.619 20
Naphthalene 0.00500 0.00431 0.00431 86.2 86.2 54.0-135 0.000 20
(S) Toluene-d8 103 100 80.0-120
(S) 4-Bromofluorobenzene 95.3 97.9 77.0-126
(S) 1,2-Dichloroethane-d4 119 121 70.0-130
1 Cp
2 Tc
3 Ss
4 Cn
5 Sr
6 Qc
7 Gl
8 Al
9 Sc
ACCOUNT:PROJECT:SDG:DATE/TIME:PAGE:
711 Stantec - Salt Lake City, UT 203724146 L1818673 01/28/25 19:03 20 of 28
ACCOUNT:PROJECT:SDG:DATE/TIME:PAGE:
711 Stantec - Salt Lake City, UT 203724146 L1818673 01/29/25 10:53 20 of 28
QUALITY CONTROL SUMMARYWG2438187
Volatile Organic Compounds (GC/MS) by Method 8260B L1818673-01,02,03
Method Blank (MB)
(MB) R4169684-3 01/22/25 23:01
MB Result MB Qualifier MB MDL MB RDL
Analyte mg/kg mg/kg mg/kg
Benzene U 0.000467 0.00100
Toluene U 0.00130 0.00500
Ethylbenzene U 0.000737 0.00250
Total Xylenes U 0.000880 0.00650
Methyl tert-butyl ether U 0.000350 0.00100
Naphthalene U 0.00488 0.0125
(S) Toluene-d8 95.8 75.0-131
(S) 4-Bromofluorobenzene 107 67.0-138
(S) 1,2-Dichloroethane-d4 90.4 70.0-130
Laboratory Control Sample (LCS) • Laboratory Control Sample Duplicate (LCSD)
(LCS) R4169684-1 01/22/25 21:24 • (LCSD) R4169684-2 01/22/25 21:43
Spike Amount LCS Result LCSD Result LCS Rec.LCSD Rec.Rec. Limits LCS Qualifier LCSD Qualifier RPD RPD Limits
Analyte mg/kg mg/kg mg/kg %%%%%
Benzene 0.125 0.143 0.135 114 108 70.0-123 5.76 20
Toluene 0.125 0.129 0.123 103 98.4 75.0-121 4.76 20
Ethylbenzene 0.125 0.135 0.128 108 102 74.0-126 5.32 20
Total Xylenes 0.375 0.410 0.386 109 103 72.0-127 6.03 20
Methyl tert-butyl ether 0.125 0.120 0.103 96.0 82.4 66.0-132 15.2 20
Naphthalene 0.125 0.153 0.157 122 126 59.0-130 2.58 20
(S) Toluene-d8 95.4 96.6 75.0-131
(S) 4-Bromofluorobenzene 109 108 67.0-138
(S) 1,2-Dichloroethane-d4 95.4 94.6 70.0-130
1 Cp
2 Tc
3 Ss
4 Cn
5 Sr
6 Qc
7 Gl
8 Al
9 Sc
ACCOUNT:PROJECT:SDG:DATE/TIME:PAGE:
711 Stantec - Salt Lake City, UT 203724146 L1818673 01/28/25 19:03 21 of 28
ACCOUNT:PROJECT:SDG:DATE/TIME:PAGE:
711 Stantec - Salt Lake City, UT 203724146 L1818673 01/29/25 10:53 21 of 28
QUALITY CONTROL SUMMARYWG2441500
Volatile Organic Compounds (GC/MS) by Method 8260B/8260B/OA1 L1818673-04,05
Method Blank (MB)
(MB) R4171215-4 01/23/25 20:55
MB Result MB Qualifier MB MDL MB RDL
Analyte mg/l mg/l mg/l
TPH (GC/MS) Low Fraction U 0.108 0.500
Benzene U 0.0000941 0.00100
Toluene U 0.000278 0.00100
Ethylbenzene U 0.000137 0.00100
Xylenes, Total U 0.000174 0.00300
Methyl tert-butyl ether U 0.000101 0.00100
Naphthalene 0.00139 J 0.00100 0.00500
(S) Toluene-d8 87.6 80.0-120
(S) 4-Bromofluorobenzene 98.5 77.0-126
(S) 1,2-Dichloroethane-d4 98.1 70.0-130
Laboratory Control Sample (LCS) • Laboratory Control Sample Duplicate (LCSD)
(LCS) R4171215-1 01/23/25 18:29 • (LCSD) R4171215-5 01/23/25 22:17
Spike Amount LCS Result LCSD Result LCS Rec.LCSD Rec.Rec. Limits LCS Qualifier LCSD Qualifier RPD RPD Limits
Analyte mg/l mg/l mg/l %%%%%
Benzene 0.00500 0.00549 0.00576 110 115 70.0-123 4.80 20
Toluene 0.00500 0.00457 0.00495 91.4 99.0 79.0-120 7.98 20
Ethylbenzene 0.00500 0.00445 0.00468 89.0 93.6 79.0-123 5.04 20
Xylenes, Total 0.0150 0.0138 0.0144 92.0 96.0 79.0-123 4.26 20
Methyl tert-butyl ether 0.00500 0.00539 0.00553 108 111 68.0-125 2.56 20
Naphthalene 0.00500 0.00382 0.00401 76.4 80.2 54.0-135 4.85 20
(S) Toluene-d8 89.6 91.9 80.0-120
(S) 4-Bromofluorobenzene 97.9 99.2 77.0-126
(S) 1,2-Dichloroethane-d4 102 99.2 70.0-130
Laboratory Control Sample (LCS)
(LCS) R4171215-2 01/23/25 19:31
Spike Amount LCS Result LCS Rec.Rec. Limits LCS Qualifier
Analyte mg/l mg/l %%
TPH (GC/MS) Low Fraction 5.00 5.31 106 66.0-132
(S) Toluene-d8 91.1 80.0-120
(S) 4-Bromofluorobenzene 105 77.0-126
(S) 1,2-Dichloroethane-d4 101 70.0-130
1 Cp
2 Tc
3 Ss
4 Cn
5 Sr
6 Qc
7 Gl
8 Al
9 Sc
ACCOUNT:PROJECT:SDG:DATE/TIME:PAGE:
711 Stantec - Salt Lake City, UT 203724146 L1818673 01/28/25 19:03 22 of 28
ACCOUNT:PROJECT:SDG:DATE/TIME:PAGE:
711 Stantec - Salt Lake City, UT 203724146 L1818673 01/29/25 10:53 22 of 28
QUALITY CONTROL SUMMARYWG2438907
Semi-Volatile Organic Compounds (GC) by Method 8015 L1818673-01,02,03
Method Blank (MB)
(MB) R4170218-1 01/24/25 11:33
MB Result MB Qualifier MB MDL MB RDL
Analyte mg/kg mg/kg mg/kg
TPH (GC/FID) High Fraction U 0.769 4.00
(S) o-Terphenyl 78.4 18.0-148
Laboratory Control Sample (LCS)
(LCS) R4170218-2 01/24/25 11:48
Spike Amount LCS Result LCS Rec.Rec. Limits LCS Qualifier
Analyte mg/kg mg/kg %%
TPH (GC/FID) High Fraction 50.0 35.3 70.6 50.0-150
(S) o-Terphenyl 91.3 18.0-148
L1818485-11 Original Sample (OS) • Matrix Spike (MS) • Matrix Spike Duplicate (MSD)
(OS) L1818485-11 01/24/25 13:24 • (MS) R4170218-3 01/24/25 13:38 • (MSD) R4170218-4 01/24/25 13:52
Spike Amount
(dry)
Original Result
(dry)MS Result (dry)MSD Result
(dry)MS Rec.MSD Rec.Dilution Rec. Limits MS Qualifier MSD Qualifier RPD RPD Limits
Analyte mg/kg mg/kg mg/kg mg/kg %%%%%
TPH (GC/FID) High Fraction 57.7 38.6 81.4 41.6 74.3 5.21 5 50.0-150 J3 J6 64.8 20
(S) o-Terphenyl 61.4 63.7 18.0-148
1 Cp
2 Tc
3 Ss
4 Cn
5 Sr
6 Qc
7 Gl
8 Al
9 Sc
ACCOUNT:PROJECT:SDG:DATE/TIME:PAGE:
711 Stantec - Salt Lake City, UT 203724146 L1818673 01/28/25 19:03 23 of 28
ACCOUNT:PROJECT:SDG:DATE/TIME:PAGE:
711 Stantec - Salt Lake City, UT 203724146 L1818673 01/29/25 10:53 23 of 28
QUALITY CONTROL SUMMARYWG2438146
Semi-Volatile Organic Compounds (GC) by Method 8015D L1818673-06,07,08,09
Method Blank (MB)
(MB) R4170641-1 01/25/25 11:02
MB Result MB Qualifier MB MDL MB RDL
Analyte mg/l mg/l mg/l
TPH (GC/FID) High Fraction 0.0737 J 0.0678 0.100
(S) o-Terphenyl 95.0 31.0-160
Laboratory Control Sample (LCS)
(LCS) R4170641-2 01/25/25 11:22
Spike Amount LCS Result LCS Rec.Rec. Limits LCS Qualifier
Analyte mg/l mg/l %%
TPH (GC/FID) High Fraction 1.50 1.38 92.0 50.0-150
(S) o-Terphenyl 88.5 31.0-160
L1818545-01 Original Sample (OS) • Matrix Spike (MS) • Matrix Spike Duplicate (MSD)
(OS) L1818545-01 01/25/25 11:43 • (MS) R4170641-3 01/25/25 12:03 • (MSD) R4170641-4 01/25/25 12:23
Spike Amount Original Result MS Result MSD Result MS Rec.MSD Rec.Dilution Rec. Limits MS Qualifier MSD Qualifier RPD RPD Limits
Analyte mg/l mg/l mg/l mg/l %%%%%
TPH (GC/FID) High Fraction 1.50 ND 1.54 1.43 103 95.3 1 50.0-150 7.41 20
(S) o-Terphenyl 102 96.0 31.0-160
1 Cp
2 Tc
3 Ss
4 Cn
5 Sr
6 Qc
7 Gl
8 Al
9 Sc
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GLOSSARY OF TERMS
Guide to Reading and Understanding Your Laboratory Report
The information below is designed to better explain the various terms used in your report of analytical results from the Laboratory. This is not
intended as a comprehensive explanation, and if you have additional questions please contact your project representative.
Results Disclaimer - Information that may be provided by the customer, and contained within this report, include Permit Limits, Project Name,
Sample ID, Sample Matrix, Sample Preservation, Field Blanks, Field Spikes, Field Duplicates, On-Site Data, Sampling Collection Dates/Times, and
Sampling Location. Results relate to the accuracy of this information provided, and as the samples are received.
Abbreviations and Definitions
(dry)Results are reported based on the dry weight of the sample. [this will only be present on a dry report basis for soils].
MDL Method Detection Limit.
ND Not detected at the Reporting Limit (or MDL where applicable).
RDL Reported Detection Limit.
RDL (dry)Reported Detection Limit.
Rec.Recovery.
RPD Relative Percent Difference.
SDG Sample Delivery Group.
(S)
Surrogate (Surrogate Standard) - Analytes added to every blank, sample, Laboratory Control Sample/Duplicate and
Matrix Spike/Duplicate; used to evaluate analytical efficiency by measuring recovery. Surrogates are not expected to be
detected in all environmental media.
U Not detected at the Reporting Limit (or MDL where applicable).
Analyte The name of the particular compound or analysis performed. Some Analyses and Methods will have multiple analytes
reported.
Dilution
If the sample matrix contains an interfering material, the sample preparation volume or weight values differ from the
standard, or if concentrations of analytes in the sample are higher than the highest limit of concentration that the
laboratory can accurately report, the sample may be diluted for analysis. If a value different than 1 is used in this field, the
result reported has already been corrected for this factor.
Limits
These are the target % recovery ranges or % difference value that the laboratory has historically determined as normal
for the method and analyte being reported. Successful QC Sample analysis will target all analytes recovered or
duplicated within these ranges.
Original Sample The non-spiked sample in the prep batch used to determine the Relative Percent Difference (RPD) from a quality control
sample. The Original Sample may not be included within the reported SDG.
Qualifier
This column provides a letter and/or number designation that corresponds to additional information concerning the result
reported. If a Qualifier is present, a definition per Qualifier is provided within the Glossary and Definitions page and
potentially a discussion of possible implications of the Qualifier in the Case Narrative if applicable.
Result
The actual analytical final result (corrected for any sample specific characteristics) reported for your sample. If there was
no measurable result returned for a specific analyte, the result in this column may state “ND” (Not Detected) or “BDL”
(Below Detectable Levels). The information in the results column should always be accompanied by either an MDL
(Method Detection Limit) or RDL (Reporting Detection Limit) that defines the lowest value that the laboratory could detect
or report for this analyte.
Uncertainty
(Radiochemistry)Confidence level of 2 sigma.
Case Narrative (Cn)
A brief discussion about the included sample results, including a discussion of any non-conformances to protocol
observed either at sample receipt by the laboratory from the field or during the analytical process. If present, there will
be a section in the Case Narrative to discuss the meaning of any data qualifiers used in the report.
Quality Control
Summary (Qc)
This section of the report includes the results of the laboratory quality control analyses required by procedure or
analytical methods to assist in evaluating the validity of the results reported for your samples. These analyses are not
being performed on your samples typically, but on laboratory generated material.
Sample Chain of
Custody (Sc)
This is the document created in the field when your samples were initially collected. This is used to verify the time and
date of collection, the person collecting the samples, and the analyses that the laboratory is requested to perform. This
chain of custody also documents all persons (excluding commercial shippers) that have had control or possession of the
samples from the time of collection until delivery to the laboratory for analysis.
Sample Results (Sr)
This section of your report will provide the results of all testing performed on your samples. These results are provided
by sample ID and are separated by the analyses performed on each sample. The header line of each analysis section for
each sample will provide the name and method number for the analysis reported.
Sample Summary (Ss)This section of the Analytical Report defines the specific analyses performed for each sample ID, including the dates and
times of preparation and/or analysis.
Qualifier Description
B The same analyte is found in the associated blank.
C3 The reported concentration is an estimate. The continuing calibration standard associated with this data responded low.
Method sensitivity check is acceptable.
J The identification of the analyte is acceptable; the reported value is an estimate.
J3 The associated batch QC was outside the established quality control range for precision.
J6 The sample matrix interfered with the ability to make any accurate determination; spike value is low.
1 Cp
2 Tc
3 Ss
4 Cn
5 Sr
6 Qc
7 Gl
8 Al
9 Sc
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ACCREDITATIONS & LOCATIONS

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* Not all certifications held by the laboratory are applicable to the results reported in the attached report.
* Accreditation is only applicable to the test methods specified on each scope of accreditation held by Pace Analytical.
1 Cp
2 Tc
3 Ss
4 Cn
5 Sr
6 Qc
7 Gl
8 Al
9 Sc
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