HomeMy WebLinkAboutDERR-2024-012055
Stantec Consulting Services Inc.
2890 East Cottonwood Parkway
Suite 300
Salt Lake City UT 84121-7283
November 11, 2024
Project/File: 203720675
Nicole Chavez
Utah Department of Environmental Quality
Division of Environmental Response and Remediation
195 North 1950 West, First Floor
Salt Lake City, Utah 84116
Reference: Semiannual Groundwater Monitoring Report – 7-Eleven Store No. 35508
712 South State Street, Clearfield, Utah
Facility ID 3000334, Release Site NGN
Dear Ms. Chavez,
On behalf of 7-Eleven, Inc. (7-Eleven), Stantec Consulting Services Inc. (Stantec) presents the October 9,
2024 semiannual groundwater monitoring and sampling results for 7-Eleven Store No. 35508 (the Site).
The Site is located at 712 South State Street, Clearfield, Utah (Figure 1). The Utah Department of
Environmental Quality (UDEQ) Division of Environmental Response and Remediation (DERR) refers to the
Site as Facility ID 3000334 and Release Site NGN.
The October 2024 event is the first of two semiannual groundwater monitoring and sampling events
authorized under Work Plan and Budget (WP&B) NGN-15 which was approved by the DERR in a letter
dated August 21, 2024.
BACKGROUND
7-Eleven historically operated the Site as a convenience store with retail sale of gasoline and diesel fuels.
7-Eleven ceased operations at the Site on October 7, 2024. The UST and distribution system consists of
three 10,000-gallon, single wall, fiberglass-reinforced plastic USTs, associated product piping, and four
product dispenser islands. The UST system was installed in 1989.
A suspected release of petroleum from the UST system was reported for the Site on May 14, 2015. The
suspected release was based on a failed tank tightness test associated with the center 10,000-gallon
unleaded gasoline tank. After tank repairs were completed, the repaired tank passed a follow-up tank
tightness test on May 27, 2015.
On and off-site investigation and remediation efforts conducted since the discovery of the release are
summarized below.
The initial subsurface investigation was conducted in August 2015.
Additional subsurface investigation was conducted in December 2015.
November 11, 2024
Page 2 of 6
Reference: Semiannual Groundwater Monitoring Report – 7-Eleven Store No. 35508
712 South State Street, Clearfield, Utah
Facility ID 3000334, Release Site NGN
In October of 2016, two-inch monitoring wells MW-1R through MW-7R and MW-8 were installed.
The original one-inch monitoring wells were abandoned except for MW-2 as it periodically
contained light non-aqueous phased liquid (LNAPL).
A 30-day high-vacuum dual-phase extraction (HVDPE) pilot study event was conducted from
September 11 through October 11, 2017.
In November 2017, off-site monitoring well MW-9 was installed on the adjacent car dealership
property to the south.
Sub-slab vapor sampling was conducted beneath the store building in 2018.
In August of 2019, monitoring wells MW-10 and MW-11 were installed off-site on the adjacent
autobody property to the west, and well MW-12 was installed on-site.
Semiannual to quarterly groundwater monitoring events were conducted between 2016 and 2021,
and between the second quarter of 2023 and the first quarter of 2024.
Monthly LNAPL monitoring and periodic LNAPL recovery events were conducted between 2019
and 2022.
In March 2021, significant LNAPL was observed in well MW-2R and prompted LNAPL sampling for
product identification analysis. The LNAPL was originally identified by Chemtech-Ford Analytical
Laboratories (CF) of Sandy, Utah as jet fuel JP-4 in June 2021. LNAPL sampling and product
identification analysis was repeated in January 2023. Apex Laboratories, LLC (Apex) of Tigard,
Oregon subsequently identified the LNAPL as degraded gasoline. Upon reviewing the original
product identification results obtained by CF, Apex concluded those results were similar to their
own January 2023 results and suspected that the evaluation performed by CF was possibly flawed.
GROUNDWATER MONITORING AND SAMPLING
The October 9, 2024 groundwater monitoring and sampling was conducted by a DERR Certified Soil and
Groundwater Sampler and in accordance with the protocols established in the Utah Underground Storage
Tank Rules, R311-205. Twelve of the thirteen site monitoring wells were included in the October 9, 2024
monitoring and sampling event. Monitoring well MW-2 is not sampled as it is only used for gauging/LNAPL
monitoring. Stantec did not gauge MW-2 during the October 9, 2024 event as the casing appeared to be
blocked with sediment and could not be gauged during the March 20, 2024 event.
Prior to purging and sampling, the static groundwater levels and/or LNAPL thicknesses were gauged in
each well to the nearest one hundredth of a foot using a battery-powered product/water interface probe.
Wells without LNAPL present were then purged via weighted, plastic, disposable bailer until three well
volumes were removed. The wells were then allowed to recharge to at least 80 percent of the original water
column prior to sampling.
Groundwater samples were collected via bailer and decanted into amber glass volatile organic analysis
(VOA) containers with hydrochloric acid (HCl) preservative. Samples for analysis of total petroleum
hydrocarbons-gasoline range organics (TPH-GRO), methyl tert-butyl ether, benzene, toluene,
ethylbenzene, total xylenes, and naphthalene (MBTEXN) by EPA Method 8260B were collected in three
40-millileter (mL) VOAs containing hydrochloric acid (HCl) preservative. Samples for analysis of total
petroleum hydrocarbons diesel range organics (TPH-DRO) by EPA Method 8015 were collected in two
40-mL VOAs containing HCl preservative. Samples were then labeled with the sample identification,
collection date, and time, and placed into an ice chilled cooler and transferred to the laboratory courier for
delivery under chain-of-custody (COC) documentation to Utah certified Pace Analytical National (Pace) of
November 11, 2024
Page 3 of 6
Reference: Semiannual Groundwater Monitoring Report – 7-Eleven Store No. 35508
712 South State Street, Clearfield, Utah
Facility ID 3000334, Release Site NGN
Mount Juliet, Tennessee. Stantec also collected a blind duplicate sample from MW-5R; the duplicate was
analyzed for MBTEXN, TPH-GRO, and TPH-DRO. Pace prepared a trip blank sample that accompanied
the sample bottles during shipment and collection; the trip black was analyzed for MBTEXN and TPH-GRO.
RESULTS
Figure 1 illustrates the October 9, 2024 groundwater elevations across the Site. Respectively, Figure 2
and Figure 3 illustrate the October 9, 2024 isoconcentration maps for dissolved benzene and TPH-GRO
concentrations. Table 2 summarizes historical and current groundwater analytical results and groundwater
elevation data. Graph 1 shows LNAPL thicknesses and groundwater elevation data for MW-2R.
Respectively, Graph 2 and Graph 3 show dissolved concentrations of benzene and TPH-GRO, including
depth to groundwater data, in MW-5R. Respectively, Graph 4 and Graph 5 show dissolved concentrations
of benzene and TPH-GRO in MW-8. Respectively, Graph 6 and Graph 7 show dissolved concentrations
of benzene and TPH-GRO in MW-9. Copies of the laboratory analytical report and the chain of custody
documentation are provided in Attachment A.
Field and analytical results for the October 9, 2024 groundwater monitoring event are summarized below.
Analytical results are compared to the Initial Screenings Levels (ISLs) and Tier 1 Screening Levels (TSLs)
established by the UDEQ DERR Petroleum Storage Tank (PST) Branch.
MW-2R was not sampled as it contained LNAPL. The LNAPL thickness in MW-2R was
approximately two hundredths of a foot.
The LNAPL sorbent sock was replaced in MW-2R. The spent sorbent sock was disposed of at
Sump & Trap Cleaning (now Envirocare) in Salt Lake City.
In wells not containing LNAPL, shallow groundwater was measured at depths ranging from 10.57
(MW-5R) to 13.23 (MW-9) feet (ft) below top of casing. A southwest hydraulic gradient of
approximately 0.024 ft per foot was measured between wells MW-1R and MW-11.
In the groundwater sample collected from MW-5R, the dissolved toluene, ethylbenzene, and
TPH-DRO concentrations exceeded the respective ISLs, and the laboratory reporting limit (RL) for
benzene also exceeded the ISL. The dissolved total xylenes concentration exceed the TSL, and
the RL for TPH-GRO also exceeded the TSL.
In the groundwater sample collected from MW-9, the dissolved benzene and TPH-GRO
concentrations exceeded the respective ISLs.
The relative percent differences (RPDs) calculated between the parent and duplicate samples
collected from MW-5R were within the generally accepted standards. The duplicate TPH-GRO
result was used for the MW-5R dissolved concentrations versus time plot shown in Graph 3 as the
parent sample result was below the RL.
No dissolved petroleum hydrocarbons were detected at concentrations above the RLs in the trip
blank.
All other concentrations were either below ISLs or were not reported above the RLs.
CONCLUSIONS
Based on the field and analytical data summarized above, and comparison of the results of this event with
the historical data, Stantec presents the following conclusions.
November 11, 2024
Page 4 of 6
Reference: Semiannual Groundwater Monitoring Report – 7-Eleven Store No. 35508
712 South State Street, Clearfield, Utah
Facility ID 3000334, Release Site NGN
October 2024 relative groundwater elevations were lower in Site monitoring wells when compared
to March 2024 relative groundwater elevations, decreasing by an average of half a foot. The
decrease in groundwater elevations is consistent with the seasonal decrease in precipitation from
wet winter to dry summer.
o The southwest groundwater flow direction remains relatively consistent with previous
groundwater monitoring events.
The LNAPL thickness in MW-2R decreased slightly from an apparent thickness of 0.04 feet
measured in March 2024 to 0.02 feet measured in October 2024.
Some dissolved petroleum hydrocarbon concentrations in MW-5R and MW-9 decreased while
others increased between the March 2024 and October 2024 monitoring events.
In MW-5R, dissolved benzene, toluene, ethylbenzene, and TPH-DRO concentrations remain above
ISLs and total xylenes and TPH-GRO concentrations remain above TSLs.
In MW-9, dissolved benzene and TPH-GRO concentrations remain above ISLs.
In MW-8, dissolved benzene and TPH-GRO concentrations remain below ISLs.
In MW-11, the dissolved benzene concentration remains below the RL.
Consistent with observations in previous monitoring events, dissolved petroleum hydrocarbon
concentrations in source area wells (such as MW-5R) tend to increase with increased groundwater
elevations at the Site and vice versa. This suggests groundwater is interacting with more of the
smear zone (more LNAPL becomes submerged) when groundwater elevations are high.
Concentrations in downgradient wells tend to decrease with increased groundwater elevations at
the Site, possibly due to more dilution by the increased volume of groundwater in the formation.
RECOMMENDATIONS
7-Eleven will close the UST system by removal in March 2025, once asphalt plants begin producing asphalt
again following winter. Due to remaining petroleum hydrocarbon impacts, 7-Eleven intends to utilize the
DERR corrective action plan (CAP) process to perform impacted soil removal in conjunction with UST
closure activities. 7-Eleven will also consider conducting additional remedial actions coupled with soil
excavation such as groundwater removal and treatment or disposal and application of a soil amendment.
Stantec will initiate the CAP process by preparing a WP&B for corrective action method evaluation, a CAP
meeting with DERR, preparation of a letter to summarize the CAP meeting, and the public notification
process. Stantec will prepare a second WP&B to present the scope and costs of the agreed on corrective
action.
November 11, 2024
Page 5 of 6
Reference: Semiannual Groundwater Monitoring Report – 7-Eleven Store No. 35508
712 South State Street, Clearfield, Utah
Facility ID 3000334, Release Site NGN
LIMITATIONS AND CERTIFICATION
The conclusions in the Report titled Semiannual Groundwater Monitoring Report – 7-Eleven Store No.
35508 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-Eleven, 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.
All information, conclusions, and recommendations provided by Stantec in this document regarding the Site
have been prepared under the supervision of, and reviewed by, the certified UST consultant whose
signature appears below.
November 11, 2024
Page 6 of 6
Reference: Semiannual Groundwater Monitoring Report – 7-Eleven Store No. 35508
712 South State Street, Clearfield, Utah
Facility ID 3000334, Release Site NGN
If you have any questions or require any additional information, please contact Anna Skinner via the contact
information provided below.
Sincerely,
STANTEC CONSULTING SERVICES INC.
Anna Skinner
Project Manager
Phone: (801) 743-4815
anna.skinner@stantec.com
Attachments: Figure 1 – Groundwater Contour Map, October 9, 2024
Figure 2 – Dissolved Benzene Isoconcentration Map, October 9, 2024
Figure 3 – Dissolved TPH-GRO Isoconcentration Map, October 9, 2024
Table 1 – LNAPL Monitoring Results
Table 2 – Groundwater Monitoring and Analytical Results
Graph 1 – MW-2R LNAPL Thickness vs Time
Graph 2 – MW-5R Benzene Concentration vs. Time
Graph 3 – MW-5R TPH-GRO Concentration vs. Time
Graph 4 – MW-8 Benzene Concentration vs. Time
Graph 5 – MW-8 TPH-GRO Concentration vs. Time
Graph 6 – MW-9 Benzene Concentration vs. Time
Graph 7 – MW-9 TPH-GRO Concentration vs. Time
Attachment A – Laboratory Analytical Report and Chain-of-Custody Documentation
c. File / 7-Eleven Inc.
John Wainwright, Stantec
Reference: Semiannual Groundwater Monitoring Report – 7-Eleven Store No. 35508
712 South State Street, Clearfield, Utah
Facility ID 3000334, Release Site NGN
FIGURES
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T
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7-ELEVEN STORE
NO. 35508
G
G
G
G
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T
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E E E E E E
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STORE
E
E
E
E
MW-8(84.05)
MW-2
MW-4R(86.58)
MW-3R(87.46)
MW-5R(86.40)
MW-1R
(88.46)
MW-2R(87.01)*
MW-6R(85.12)
7 0 0 S O U T H S T R E E T
UTAH TITLE
LOANS
S
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A
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PEDESTAL
SIGN
WATER
METER
CANOPY
DISPENSERS
UST
BASIN
PRODUCT
PIPING
LIGHT
POLE
TRANSFORMERTRASH
ENCLOSURE
TRANSFORMER
MW-7R(84.04)
TRANSFORMER
SSVMP-1
MW-9(81.83)
MW-10(82.25)
MW-12(86.71)
AB
R
A
A
U
T
O
B
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D
Y
S
H
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MW-11(81.67)
203720675 STA AMS JPW 11/08/24
1
GROUNDWATER CONTOUR
MAP
OCTOBER 09, 2024STORE #35508
712 SOUTH STATE STREET
CLEARFIELD, UTAH
FOR:
JOB NUMBER:DRAWN BY:CHECKED BY:APPROVED BY:DATE:
FILEPATH:C:\Users\SAguinaldo\Desktop\2024\SLC\203720675\4Q 2024\FIG 1_7-11_35508_GW CONTOUR MAP.dwg | Layout Tab: 1 | Drafter: SAguinaldo | Nov 11, 2024 at 10:54
FIGURE:
No warranty is made by Stantec Consulting Services Inc. 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.
N 0 40 80
APPROXIMATE SCALE IN FEET
ELEVEN
WESTBRIDGE
AUTO
LEGEND
APPROXIMATE PROPERTY BOUNDARY
FENCE LINE
GAS LINE
TELEPHONE LINE
ELECTRIC LINE
X X X X X
G G
T T
E E
MONITORING WELL LOCATIONMW-1
(88.46)
85
RELATIVE GROUNDWATER
INFERRED GROUNDWATER FLOW DIRECTION
ELEVATION (FEET)
STORM DRAINSDSD
*CORRECTED RELATIVE GROUNDWATER ELEVATION
SSVMP-1 SUB-SLAB VAPOR MONITORING POINT
RELATIVE GROUNDWATER ELEVATION CONTOUR (FEET)
DASHED WHERE INFERRED
PHONE:
2890 E COTTONWOOD PKWY, STE 300
SALT LAKE CITY, UTAH
(801) 261-0090
82
83
8
5
8
6
8
7
88
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3
82
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7-ELEVEN STORE
NO. 35508
G
G
G
G
G
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G
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E E E E E E
E
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STORE
E
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E
MW-83.58
MW-2
MW-4R<1.00
MW-3R<1.00
MW-5R<47.1
MW-1R<1.00
MW-6R<1.00
7 0 0 S O U T H S T R E E T
UTAH TITLE
LOANS
S
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A
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E
S
T
R
E
E
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PEDESTAL
SIGN
WATER
METER
CANOPY
DISPENSERS
UST
BASIN
PRODUCT
PIPING
LIGHT
POLE
TRANSFORMERTRASH
ENCLOSURE
TRANSFORMER
MW-7R<1.00
TRANSFORMER
MW-9
35.2
MW-10<1.00
MW-11<1.00
SSVMP-1
AB
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A
A
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MW-2R
LNAPL
MW-12<1.00
203720675 STA AMS JPW
2
DISSOLVED BENZENE
ISOCONCENTRATION MAP
OCTOBER 09, 2023STORE #35508
712 SOUTH STATE STREET
CLEARFIELD, UTAH
FOR:
JOB NUMBER:DRAWN BY:CHECKED BY:APPROVED BY:DATE:
FILEPATH:C:\Users\SAguinaldo\Desktop\2024\SLC\203720675\4Q 2024\FIG 2_7-11_35508_DIS BENZ MAP.dwg | Layout Tab: 2 | Drafter: SAguinaldo | Nov 11, 2024 at 10:52
FIGURE:
No warranty is made by Stantec Consulting Services Inc. 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.
N 0 40 80
APPROXIMATE SCALE IN FEET
ELEVEN
LEGEND
APPROXIMATE PROPERTY BOUNDARY
FENCE LINE
GAS LINE
TELEPHONE LINE
ELECTRIC LINE
X X X X X
G G
T T
E E
MONITORING WELL LOCATIONMW-1
STORM DRAINSDSD
SSVMP-1 SUB-SLAB VAPOR MONITORING POINT
5
DISSOLVED BENZENE CONCENTRATIONMICROGRAMS PER LITER (µg/L)
LIGHT NON-AQUEOUS PHASE LIQUIDLNAPL
<1.0
11/08/24
WESTBRIDGE
AUTO
INFERRED BENZENE ISOCONCENTRATION CONTOUR (µg/L)
DASHED WHERE INFERRED
PHONE:
2890 E COTTONWOOD PKWY, STE 300
SALT LAKE CITY, UTAH
(801) 261-0090
5
NAPL
T
T
T
T
T T T T T
XXXXXXXXXXXXXXXXX
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7-ELEVEN STORE
NO. 35508
G
G
G
G
G
G
G
G
G
G
G
G
G
G
T
T
T
T
T
T
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G
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E
E E E E E E
E
E
STORE
E
E
E
E
MW-8<500
MW-4R<500
MW-3R<500
MW-5R
70,000
MW-6R<500
AB
R
A
A
U
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O
B
O
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7 0 0 S O U T H S T R E E T
UTAH TITLE
LOANS
S
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A
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T
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E
E
T
PEDESTAL
SIGN
WATER
METER
CANOPY
DISPENSERS
UST
BASIN
PRODUCT
PIPING
LIGHT
POLE
TRANSFORMERTRASH
ENCLOSURE
TRANSFORMER
MW-7R<500
TRANSFORMER
MW-9
7,440
MW-10<500
MW-12<500
MW-11<500
SSVMP-1
MW-1R<500
MW-2
MW-2R
LNAPL
203720675 STA AMS JPW
3
DISSOLVED TPH-GRO
ISOCONCENTRATION MAP
OCTOBER 09, 2023STORE #35508
712 SOUTH STATE STREET
CLEARFIELD, UTAH
FOR:
JOB NUMBER:DRAWN BY:CHECKED BY:APPROVED BY:DATE:
FILEPATH:C:\Users\SAguinaldo\Desktop\2024\SLC\203720675\4Q 2024\FIG 3_7-11_35508_TPH-GRO MAP.dwg | Layout Tab: 3 | Drafter: SAguinaldo | Nov 11, 2024 at 10:51
FIGURE:
No warranty is made by Stantec Consulting Services Inc. 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.
N 0 40 80
APPROXIMATE SCALE IN FEET
ELEVEN
LEGEND
APPROXIMATE PROPERTY BOUNDARY
FENCE LINE
GAS LINE
TELEPHONE LINE
ELECTRIC LINE
X X X X X
G G
T T
E E
MONITORING WELL LOCATIONMW-1
STORM DRAINSDSD
SSVMP-1
1,000
LIGHT NON-AQUEOUS PHASE LIQUIDLNAPL
70,000
SUB-SLAB VAPOR MONITORING POINT
DISSOLVED TPH-GRO CONCENTRATION
MICROGRAMS PER LITER (µg/L)
INFERRED TPH-GRO ISOCONCENTRATION CONTOUR (µg/L)
TOTAL PETROLEUM HYDROCARBONS
GASOLINE RANGE ORGANICS
TPH-GRO
11/08/23
WESTBRIDGE
AUTO
DASHED WHERE INFERRED
PHONE:
2890 E COTTONWOOD PKWY, STE 300
SALT LAKE CITY, UTAH
(801) 261-0090
LNA
P
L
10,000
10,000
1,000
1,00
0
Reference: Semiannual Groundwater Monitoring Report – 7-Eleven Store No. 35508
712 South State Street, Clearfield, Utah
Facility ID 3000334, Release Site NGN
TABLES
11/01/16 11.37 11.45 0.08 08/04/15 --11.01 --
12/13/16 11.64 11.70 0.06 12/10/15 --13.00 --
03/03/17 9.74 10.03 0.29 05/25/16 10.47 12.58 2.11
05/01/17 9.64 9.89 0.25 08/04/16 10.73 10.82 0.09
06/15/17 9.69 9.93 0.24 11/01/16 11.22 12.45 1.23
11/14/17 --11.01 --12/13/16 11.43 12.04 0.61
03/21/18 11.95 14.14 2.19 05/01/17 9.82 9.88 0.06
06/28/18 11.08 12.53 1.45 09/25/19 10.57 11.43 0.86
12/19/18 12.10 13.50 1.40 12/17/19 11.31 11.52 0.21
08/22/19 9.33 9.53 0.20 01/24/20 --11.85 --
09/25/19 10.57 10.80 0.23 03/03/20 --11.55 --
09/27/19 10.59 10.84 0.25 04/02/20 --11.61 --
11/01/19 11.26 11.40 0.14 06/22/20 11.30 11.43 0.13
11/21/19 11.71 11.78 0.07 07/23/20 11.26 11.31 0.05
12/17/19 11.19 11.20 0.01 08/14/20 --11.41 --
01/24/20 --11.66 --09/16/20 11.31 11.39 0.08
03/03/20 --11.40 --11/13/20 11.92 11.95 0.03
04/02/20 --11.52 --12/21/20 --12.66 --
06/22/20 --11.18 --01/29/21 13.24 13.25 0.01
07/23/20 --11.04 --03/24/21 12.47 13.41 0.94
08/14/20 --11.22 --04/27/21 12.95 12.97 0.02
09/16/20 11.17 11.19 0.02 05/14/21 12.76 12.80 0.04
11/13/20 --12.20 --06/22/21 12.50 12.62 0.12
12/21/20 --12.50 --12/07/21 13.00 13.10 0.10
01/29/21 --13.00 --02/09/22 --13.12 --
03/24/21 12.30 13.65 1.35 03/31/22 --13.04 --
04/21/21 12.65 13.89 1.24 05/07/22 13.21 13.76 0.55
04/27/21 12.78 12.85 0.07 06/03/22 12.80 13.70 0.90
05/14/21 12.60 12.71 0.11 06/22/22 12.60 13.60 1.00
06/03/21 12.50 12.70 0.20 07/08/22 12.80 12.90 0.10
06/22/21 12.39 12.52 0.13 08/09/22 12.95 13.20 0.25
07/14/21 12.50 12.79 0.29 01/12/23 12.83 13.60 0.77
08/11/21 12.29 12.35 0.06 03/24/23 12.00 12.06 0.06
09/14/21 12.18 12.20 0.02 09/27/23 11.46 12.55 1.09
12/07/21 12.72 13.35 0.63 12/18/23 --12.10 --
02/09/22 12.78 13.90 1.12 03/20/24 ------
03/31/22 --12.98 --
05/07/22 12.84 14.43 1.59
06/03/22 12.60 13.75 1.15
06/22/22 12.44 13.44 1.00
07/08/22 12.70 12.82 0.12
08/09/22 12.79 13.24 0.45 08/04/16 MW-2 6
01/12/23 12.70 13.50 0.80
03/24/23 11.92 12.97 1.05
09/27/23 11.36 12.46 1.10 05/01/17 MW-2R, MW-5R 4.0
12/18/23 --12.00 --09/11/17 MW-2R, MW-5R 30 (days)
03/20/24 10.81 10.85 0.04 08/22/19 MW-2R 6.0
10/09/24 11.14 11.16 0.02 09/27/19 MW-2R 4.0
11/01/19 MW-2R 4.0
11/21/19 MW-2R 5.0
04/21/21 MW-2R 4.0
Notes:07/14/21 MW-2R 5.0
LNAPL = light non-aqueous phase liquid 06/22/22 MW-2R 6.0
Measureable LNAPL has not been present in MW-5R since June 2017. The complete
fluid level history for MW-5R is shown in Table 2.
MW-2R
712 South State Street, Clearfield, Utah
7-Eleven Store No. 35508
LNAPL Monitoring Results
MW-2
Extraction
Wells
Duration
(hours)
MW-2R, MW-3R,
MW-5R 4.512/13/16
LNAPL Recovery Events
Date
Table 1
Sample
Location Date
Depth to
LNAPL
(feet)
Depth to
Groundwater
(feet)
LNAPL
Thickness
(feet)
Sample
Location Date
Depth to
LNAPL
(feet)
Depth to
Groundwater
(feet)
LNAPL
Thickness
(feet)
fnl_dbs_35508_20241009.xlsx 1 of 1 Stantec Consulting Services Inc.
.
MTBE Benzene Toluene
Ethyl-
benzene
Total
Xylenes Naphthalene
08/04/15 -- 11.53 -- <1.00 179 156 6.10 106 <5.00 1,600 96.7 88.47
12/10/15 -- 12.75 -- <1.00 274 1,660 151 1,090 <5.00 7,070 <100 87.25
05/25/16 -- 11.72 -- <1.00 32.8 24.4 2.34 39.7 <5.00 746 <89.3 88.28
11/01/16 -- 11.92 -- <1.00 <1.00 <1.00 <1.00 <3.00 <5.00 <400 <92.6 88.08
03/03/17 -- 10.41 -- <1.00 <1.00 <1.00 <1.00 <3.00 <5.00 <400 <92.6 89.59
06/15/17 -- 10.06 -- <1.00 <1.00 <1.00 <1.00 <3.00 <5.00 <400 <96.2 89.94
11/14/17 -- 11.35 -- <1.00 <1.00 <1.00 <1.00 <3.00 <5.00 <400 <89.3 88.65
03/20/18 -- 13.09 -- <1.00 <1.00 <1.00 <1.00 <3.00 <5.00 <400 139 86.91
06/28/18 -- 11.85 -- <1.00 <1.00 <1.00 <1.00 <3.00 <5.00 <400 132 88.15
12/19/18 -- 13.03 -- <1.00 <1.00 <1.00 <1.00 <3.00 <5.00 <400 <91.6 86.97
09/25/19 -- 11.02 -- <2.00 <1.00 <1.00 <1.00 <1.00 <1.00 <50.0 <49.3 88.98
12/17/19 -- 11.79 -- <2.00 <1.00 <1.00 <1.00 <1.00 <1.00 <50.0 <99.8 88.21
04/02/20 -- 12.13 -- <2.00 <1.00 <1.00 <1.00 <1.00 <1.00 <50.0 <47.3 87.87
06/22/20 -- 11.70 --<2.004 <1.004 <1.004 <1.004 <1.004 <1.004 <50.04 <47.4 88.30
12/21/20 --13.10 -- <0.500 <0.500 <0.500 <0.500 <0.500 <1.00 <50.0 <47.9 86.90
03/24/21 --13.21 -- <0.500 <0.500 <0.500 <0.500 <0.500 <1.00 <50.0 <47.6 86.79
06/23/21 --13.02 -- <0.500 <0.500 <0.500 <0.500 <0.500 <1.00 <50.0 <47.7 86.98
09/14/21 --12.88 -- <0.500 <0.500 <0.500 <0.500 <0.500 <1.00 <50.0 <47.7 87.12
01/12/23 --13.69 --<5 <5 <12 <12 <12 <12 <125 <1,000 86.31
09/27/23 --11.84 -- <1.00 <1.00 <1.00 <1.00 <3.00 <5.00 <500 <100 88.16
12/18/23 --12.60 -- <1.00 <1.00 <1.00 <1.00 <3.00 <5.00 <500 <100 87.40
03/20/24 --11.39 -- <1.00 <1.00 <1.00 <1.00 <3.00 <5.00 <500 134 88.61
10/09/24 --11.54 -- <1.00 <1.00 <1.00 <1.00 <3.00 <5.00 <500 <100 88.46
08/04/15 --11.01 -- <1.00 4,180 6,720 374 2,760 7.51 11,100 378 88.13
12/10/15 --13.00 -- <50.0 17,100 78,600 3,940 35,900 <250 245,000 6,330 86.14
05/25/16 10.47 12.58 2.11 LNAPL LNAPL LNAPL LNAPL LNAPL LNAPL LNAPL LNAPL 87.32c
11/01/16 11.22 12.45 1.23 LNAPL LNAPL LNAPL LNAPL LNAPL LNAPL LNAPL LNAPL 86.79c
09/25/19 10.57 11.43 0.86 LNAPL LNAPL LNAPL LNAPL LNAPL LNAPL LNAPL LNAPL 87.54c
12/17/19 11.31 11.52 0.21 LNAPL LNAPL LNAPL LNAPL LNAPL LNAPL LNAPL LNAPL 86.96c
04/02/20 --11.61 --86.71
06/22/20 11.30 11.43 0.13 LNAPL LNAPL LNAPL LNAPL LNAPL LNAPL LNAPL LNAPL 86.99c
12/21/20 --12.66 --85.66
03/24/21 12.47 13.41 0.94 LNAPL LNAPL LNAPL LNAPL LNAPL LNAPL LNAPL LNAPL 85.62c
06/22/21 12.50 12.62 0.12 LNAPL LNAPL LNAPL LNAPL LNAPL LNAPL LNAPL LNAPL 85.79c
01/12/23 12.83 13.60 0.77 LNAPL LNAPL LNAPL LNAPL LNAPL LNAPL LNAPL LNAPL 85.30c
09/27/23 11.46 12.55 1.09 LNAPL LNAPL LNAPL LNAPL LNAPL LNAPL LNAPL LNAPL 86.59c
12/18/23 --12.10 -- LNAPL LNAPL LNAPL LNAPL LNAPL LNAPL LNAPL LNAPL 86.22
03/20/24 --------
11/01/16 11.37 11.45 0.08 LNAPL LNAPL LNAPL LNAPL LNAPL LNAPL LNAPL LNAPL 86.76c
03/03/17 9.74 10.03 0.29 LNAPL LNAPL LNAPL LNAPL LNAPL LNAPL LNAPL LNAPL 88.34c
06/15/17 9.69 9.93 0.24 LNAPL LNAPL LNAPL LNAPL LNAPL LNAPL LNAPL LNAPL 88.40c
11/14/17 --11.01 -- <100 2,350 24,000 1,820 14,100 <500 128,000 3,850 87.14
03/21/18 11.95 14.14 2.19 LNAPL LNAPL LNAPL LNAPL LNAPL LNAPL LNAPL LNAPL 85.65c
06/28/18 11.08 12.53 1.45 LNAPL LNAPL LNAPL LNAPL LNAPL LNAPL LNAPL LNAPL 86.71c
12/19/18 12.10 13.50 1.40 LNAPL LNAPL LNAPL LNAPL LNAPL LNAPL LNAPL LNAPL 85.70c
09/25/19 10.57 10.80 0.23 LNAPL LNAPL LNAPL LNAPL LNAPL LNAPL LNAPL LNAPL 87.52c
12/17/19 11.19 11.20 0.01 LNAPL LNAPL LNAPL LNAPL LNAPL LNAPL LNAPL LNAPL 86.96c
04/02/20 --11.52 -- <200 <100 1,530 608 5,030 <100 16,700 14,200 86.63
06/22/20 --11.18 --<2,000 <1,000 1,050 <1,000 2,540 <1,000 <50,000 7,090 86.97
12/21/20 --12.50 -- <100 <100 717 765 7,290 <200 31,800 9,620 85.65
03/24/21 12.30 13.65 1.35 LNAPL LNAPL LNAPL LNAPL LNAPL LNAPL LNAPL LNAPL 85.51c
06/22/21 12.39 12.52 0.13 LNAPL LNAPL LNAPL LNAPL LNAPL LNAPL LNAPL LNAPL 85.73c
09/14/21 12.18 12.20 0.02 LNAPL LNAPL LNAPL LNAPL LNAPL LNAPL LNAPL LNAPL 85.97c
01/12/23 12.70 13.50 0.80 <5 41 34,100 25,800 254,000 259 343,000 68,100 85.25c
09/27/23 11.36 12.46 1.10 LNAPL LNAPL LNAPL LNAPL LNAPL LNAPL LNAPL LNAPL 86.52c
12/18/23 --12.00 -- LNAPL LNAPL LNAPL LNAPL LNAPL LNAPL LNAPL LNAPL 86.15
03/20/24 10.81 10.85 0.04 LNAPL LNAPL LNAPL LNAPL LNAPL LNAPL LNAPL LNAPL 87.33c
10/09/24 11.14 11.16 0.02 LNAPL LNAPL LNAPL LNAPL LNAPL LNAPL LNAPL LNAPL 87.01c
08/04/15 --11.49 -- <1.00 4,250 15,400 925 8,150 32.2 65,800 1,250 87.45
12/10/15 --12.80 -- <20.0 405 157 63.4 331 <100 <8,000 130 86.14
05/25/16 --11.48 -- <20.0 1,470 16,200 1,460 9,420 <100 71,200 1,850 87.46
11/01/16 --11.78 -- <1.00 22.1 235 166 914 12.8 4,460 407 87.16
03/03/17 --10.17 -- <1.00 18.5 1,770 283 6,220 81.4 18,100 5,220 88.77
06/15/17 --9.91 -- <1.00 <1.00 7.86 24.5 238 23.6 4,600 1,680 89.03
11/14/17 --11.19 -- <1.00 <1.00 <1.00 7.74 34.2 <5.00 <400 449 87.75
03/20/18 --12.79 -- <1.00 <1.00 <1.00 <1.00 <3.00 <5.00 <400 <86.2 86.15
06/28/18 --11.74 -- <1.00 <1.00 <1.00 <1.00 <3.00 <5.00 <400 <94.6 87.20
12/19/18 --12.82 -- <1.00 <1.00 <1.00 <1.00 <3.00 <5.00 <400 <91.7 86.12
09/25/19 --10.96 -- <2.00 <1.00 <1.00 <1.00 <1.00 <1.00 <50.0 <47.9 87.98
12/17/19 --11.54 -- <2.00 <1.00 <1.00 <1.00 <1.00 <1.00 <50.0 <95.8 87.40
04/02/20 --11.88 -- <2.00 <1.00 <1.00 <1.00 <1.00 <1.00 <50.0 <47.4 87.06
06/22/20 --11.42 -- <2.00 <1.00 <1.00 <1.00 <1.00 <1.00 <50.0 <47.5 87.52
12/21/20 --12.86 -- <0.500 <0.500 <0.500 <0.500 <0.500 <1.00 <50.0 <47.8 86.08
03/24/21 --12.99 -- <0.500 1.88 <0.500 <0.500 <0.500 <1.00 <50.0 <47.6 85.95
06/23/21 --12.79 -- <0.500 <0.500 <0.500 <0.500 <0.500 <1.00 <50.0 <47.6 86.15
09/14/21 --12.55 -- <0.500 <0.500 <0.500 <0.500 <0.500 <1.00 <50.0 <47.7 86.39
01/12/23 --13.28 --<5 <5 <12 <12 <12 <12 <125 <1,000 85.66
09/27/23 --11.75 -- <1.00 <1.00 <1.00 <1.00 <3.00 <5.00 <500 <100 87.19
12/18/23 --12.42 -- <1.00 <1.00 <1.00 <1.00 <3.00 <5.00 <500 <200 86.52
03/20/24 --11.22 -- <1.00 <1.00 <1.00 <1.00 <3.00 <5.00 <500 140 87.72
10/09/24 --11.48 -- <1.00 <1.00 <1.00 <1.00 <3.00 <5.00 <500 <100 87.46
08/04/15 --11.33 -- <1.00 <1.00 <1.00 <1.00 <3.00 <5.00 <400 107 86.87
12/10/15 --12.53 -- <1.00 <1.00 <1.00 <1.00 <3.00 <5.00 <400 <100 85.67
05/25/16 --11.28 -- <1.00 <1.00 <1.00 <1.00 <3.00 <5.00 493 <96.2 86.92
11/01/16 --11.74 -- <1.00 <1.00 <1.00 <1.00 <3.00 <5.00 <400 <92.6 86.46
03/03/17 --10.26 -- <1.00 <1.00 <1.00 <1.00 <3.00 <5.00 <400 676 87.94
06/15/17 --10.26 -- <1.00 <1.00 <1.00 <1.00 <3.00 <5.00 <400 123 87.94
11/14/17 --11.50 -- <1.00 <1.00 <1.00 <1.00 <3.00 <5.00 448 155 86.70
03/21/18 --12.66 -- <1.00 <1.00 <1.00 <1.00 <3.00 <5.00 <400 <92.6 85.54
06/28/18 --11.81 -- <1.00 <1.00 <1.00 <1.00 <3.00 <5.00 <400 <94.4 86.39
12/19/18 --12.74 -- <1.00 <1.00 <1.00 <1.00 <3.00 <5.00 <400 <91.4 85.46
09/25/19 --11.10 -- <2.00 <1.00 <1.00 <1.00 <1.00 <1.00 <50.0 <49.3 87.10
12/17/19 --11.56 -- <2.00 <1.00 <1.00 <1.00 <1.00 <1.00 <50.0 <95.4 86.64
04/02/20 --11.88 -- <2.00 <1.00 <1.00 <1.00 <1.00 <1.00 <50.0 <47.4 86.32
06/22/20 --11.45 -- <2.00 <1.00 <1.00 <1.00 1.17 <1.00 <50.0 <47.6 86.75
12/21/20 --12.85 -- <0.500 <0.500 <0.500 <0.500 <0.500 <1.00 <50.0 <47.5 85.35
03/24/21 --12.90 -- <0.500 <0.500 <0.500 <0.500 <0.500 <1.00 <50.0 <47.7 85.30
06/23/21 --12.68 -- <0.500 <0.500 <0.500 <0.500 <0.500 <1.00 <50.0 <47.6 85.52
09/14/21 --12.44 -- <0.500 <0.500 <0.500 <0.500 <0.500 <1.00 <50.0 <47.7 85.76
01/12/23 --13.15 --<5 <5 <12 <12 <12 <12 <125 <1,000 85.05
200 5 1,000 700 10,000 700 1,000 1,000 --
200 300 3,000 4,000 10,000 700 10,000 10,000 --
Table 2
Groundwater Monitoring and Analytical Results
7-Eleven Store No. 35508
712 South State Street, Clearfield, Utah
MBTEXN Compounds
(µg/L)Depth to
LNAPL
(feet)
Depth to
Groundwater
(feet)
LNAPL
Thickness
(feet)
TPH-GRO
(µg/L)
Relative
Groundwater
Elevation
(feet)
Sample
Location Date TPH-DRO
(µg/L)
NOT SAMPLED - GAUGE ONLY
MW-1R5
MW-2
NOT SAMPLED - GAUGE ONLY
Casing blocked with sediment.
MW-3R5
MW-2R
MW-4R5
UDEQ DERR Initial Screening Level
UDEQ DERR Tier 1 Screening Level
fnl_dbs_35508_20241009.xlsx 1 of 3 Stantec Consulting Services Inc.
.
MTBE Benzene Toluene
Ethyl-
benzene
Total
Xylenes Naphthalene
Table 2
Groundwater Monitoring and Analytical Results
7-Eleven Store No. 35508
712 South State Street, Clearfield, Utah
MBTEXN Compounds
(µg/L)Depth to
LNAPL
(feet)
Depth to
Groundwater
(feet)
LNAPL
Thickness
(feet)
TPH-GRO
(µg/L)
Relative
Groundwater
Elevation
(feet)
Sample
Location Date TPH-DRO
(µg/L)
09/27/23 --11.82 -- <1.00 <1.00 <1.00 <1.00 <3.00 <5.00 <500 <100 86.38
12/18/23 --12.41 -- <1.00 <1.00 <1.00 <1.00 <3.00 <5.00 <500 <200 85.79
03/20/24 --11.29 -- <1.00 <1.00 <1.00 <1.00 <3.00 <5.00 <500 266 86.91
10/09/24 --11.62 -- <1.00 <1.00 <1.00 <1.00 <3.00 <5.00 <500 <100 86.58
12/10/15 --11.61 -- <1.00 7,840 33,100 1,550 12,800 49.3 103,000 747 85.36
05/25/16 --10.26 -- <200 14,600 56,200 2,570 21,000 <1,000 251,000 1,500 86.71
11/01/16 --10.80 -- <1.00 3,390 46,500 2,530 18,800 81.8 152,000 2,000 86.17
03/03/17 9.17 9.18 0.01 LNAPL LNAPL LNAPL LNAPL LNAPL LNAPL LNAPL LNAPL 87.80c
06/15/17 9.29 9.34 0.05 LNAPL LNAPL LNAPL LNAPL LNAPL LNAPL LNAPL LNAPL 87.67c
11/14/17 --10.53 -- <100 105 14,200 2,520 23,800 <500 115,000 4,180 86.44
03/21/18 --11.79 -- <100 <100 4,270 1,860 16,000 <500 71,800 3,640 85.18
06/28/18 --11.81 -- <1.00 <1.00 <1.00 <1.00 <3.00 <5.00 <400 <94.4 85.16
12/19/18 --11.78 -- <100 <100 9,410 1,640 15,200 <500 76,100 2,590 85.19
09/26/19 --10.12 --<500 2,450 40,800 2,590 24,000 <250 154,000 4,730 86.85
12/17/19 --10.57 --<1,000 <500 23,300 1,980 19,000 <500 86,400 <95.0 86.40
04/02/20 --10.86 --<500 <250 5,360 1,420 13,600 <250 41,100 2,680 86.11
06/22/20 --10.54 -- <200 <100 173 472 3,840 <100 13,100 2,440 86.43
12/21/20 --11.90 -- <100 <100 1,700 769 6,750 <200 27,900 2,550 85.07
03/24/21 --11.97 -- <10.0 <10.0 39.1 152 733 <20.0 4,590 1,260 85.00
06/23/21 --11.80 -- <10.0 <10.0 29.2 216 671 26.7 4,090 2,720 85.17
09/15/21 --11.56 -- <10.0 <10.0 48.4 216 1,060 23.7 4,950 1,640 85.41
01/12/23 --12.21 --<5 6 239 228 1,280 <12 3,590 5,400 84.76
09/27/23 --10.78 -- <25.0 71.1 17,300 2,450 20,300 <125 164,000 2,340 86.19
12/18/23 --11.41 -- <50.5 <47.1 11,900 1,920 18,800 <500 456,000 2,350 85.56
03/20/24 --10.19 -- <50.5 <47.1 10,400 2,180 21,500 <500 183,0007 5,180 86.78
10/09/24 -- 10.57 -- <50.5 <47.1 2,450 2,530 26,400 <500 <54,000 5,010 86.40
12/10/15 -- 12.79 -- <1.00 <1.00 <1.00 <1.00 <3.00 <5.00 <400 <100 82.40
05/25/16 -- 11.25 -- <1.00 <1.00 <1.00 <1.00 <3.00 <5.00 <400 <89.3 83.94
11/01/16 -- 11.80 -- <1.00 <1.00 <1.00 <1.00 <3.00 <5.00 <400 <92.6 83.39
03/03/17 -- 9.99 -- <1.00 <1.00 <1.00 <1.00 <3.00 <5.00 <400 <92.6 85.20
06/15/17 -- 10.35 -- <1.00 <1.00 <1.00 <1.00 <3.00 <5.00 <400 <92.6 84.84
11/14/17 -- 11.91 -- <1.00 <1.00 <1.00 <1.00 <3.00 <5.00 <400 126 83.28
03/21/18 -- 12.82 -- <1.00 <1.00 <1.00 <1.00 <3.00 <5.00 <400 <92.6 82.37
06/28/18 -- 12.24 -- <1.00 <1.00 <1.00 <1.00 <3.00 <5.00 <400 <94.7 82.95
12/19/18 -- 12.90 -- <1.00 <1.00 <1.00 <1.00 <3.00 <5.00 <400 <91.6 82.29
09/26/19 -- 11.20 -- <2.00 <1.00 <1.00 <1.00 <1.00 <1.00 <50.0 <46.4 83.99
12/17/19 -- 11.55 -- <2.00 <1.00 <1.00 <1.00 <1.00 <1.00 <50.0 3,290 85.51
04/02/20 -- 11.97 -- <2.00 <1.00 <1.00 <1.00 <1.00 <1.00 <50.0 65.6 85.09
06/22/20 -- 11.72 -- <2.00 <1.00 <1.00 <1.00 1.00 <1.00 <50.0 <47.4 85.34
12/21/20 -- 13.11 -- <0.500 <0.500 <0.500 <0.500 <0.500 <1.00 <50.0 <47.3 83.95
03/24/21 -- 13.11 -- <0.500 <0.500 <0.500 <0.500 <0.500 <1.00 <50.0 <47.7 83.95
06/22/21 -- 13.07 -- <0.500 <0.500 <0.500 <0.500 <0.500 <1.00 <50.0 <47.7 83.99
09/14/21 -- 12.78 -- <0.500 <0.500 <0.500 <0.500 <0.500 <1.00 <50.0 <47.6 84.28
01/12/23 -- 12.94 -- <5 <5 <12 <12 <12 <12 <125 <1,000 84.12
09/27/23 -- 12.00 -- <1.00 <1.00 <1.00 <1.00 <3.00 <5.00 <500 <100 85.06
12/18/23 -- 13.15 -- <1.00 <1.00 <1.00 <1.00 <3.00 <5.00 <500 <200 83.91
03/20/24 -- 11.24 -- <1.00 <1.00 <1.00 <1.00 <3.00 <5.00 <500 <100 85.82
10/09/24 -- 11.94 -- <1.00 <1.00 <1.00 <1.00 <3.00 <5.00 <500 <100 85.12
12/10/15 -- 13.31 -- <1.00 <1.00 <1.00 <1.00 <3.00 <5.00 <400 <100 81.22
05/25/16 -- 11.82 -- <1.00 <1.00 <1.00 <1.00 <3.00 <5.00 <400 <100 82.71
11/01/16 -- 12.27 -- <1.00 <1.00 <1.00 <1.00 <3.00 <5.00 <400 <92.6 82.26
03/03/17 -- 10.67 -- <1.00 <1.00 <1.00 <1.00 <3.00 <5.00 <400 <92.6 83.86
06/15/17 -- 11.04 -- <1.00 <1.00 <1.00 <1.00 <3.00 <5.00 <400 <92.6 83.49
11/14/17 -- 12.35 -- <1.00 <1.00 <1.00 <1.00 <3.00 <5.00 <400 89.3 82.18
03/21/18 -- 13.06 -- <1.00 <1.00 <1.00 <1.00 <3.00 <5.00 <400 <92.6 81.47
06/28/18 -- 12.56 -- <1.00 <1.00 <1.00 <1.00 <3.00 <5.00 <400 <94.8 81.97
12/19/18 -- 13.25 -- <1.00 <1.00 <1.00 <1.00 <3.00 <5.00 <400 <94.1 81.28
09/26/19 -- 11.83 -- <2.00 <1.00 <1.00 <1.00 <1.00 <1.00 <50.0 <57.2 82.70
12/17/19 -- 12.03 -- <2.00 <1.00 <1.00 <1.00 <1.00 <1.00 <50.0 <98.0 84.37
04/02/20 -- 12.35 -- <2.00 <1.00 <1.00 <1.00 <1.00 <1.00 <50.0 135 84.05
06/22/20 -- 12.05 -- <2.00 <1.00 <1.00 <1.00 <1.00 <1.00 <50.0 <47.4 84.35
12/21/20 -- 13.35 -- <0.500 <0.500 <0.500 <0.500 <0.500 <1.00 <50.0 <47.4 83.05
03/24/21 -- 13.34 -- <0.500 <0.500 <0.500 <0.500 <0.500 <1.00 <50.0 <47.8 83.06
06/22/21 -- 13.30 -- <0.500 <0.500 <0.500 <0.500 <0.500 <1.00 <50.0 <47.9 83.10
09/14/21 -- 12.96 -- <0.500 <0.500 <0.500 <0.500 <0.500 <1.00 <50.0 <47.7 83.44
01/12/23 -- 13.34 -- <5 <5 <12 <12 <12 <12 <125 <1,000 83.06
09/27/23 -- 12.45 -- <1.00 <1.00 <1.00 <1.00 <3.00 <5.00 <500 <100 83.95
12/18/23 -- 12.95 -- <1.00 <1.00 <1.00 <1.00 <3.00 <5.00 <500 <200 83.45
03/20/24 -- 11.78 -- <1.00 <1.00 <1.00 <1.00 <3.00 <5.00 <500 153 84.62
10/09/24 -- 12.36 -- <1.00 <1.00 <1.00 <1.00 <3.00 <5.00 <500 349 84.04
11/01/16 -- 12.45 -- <1.00 537 936 52.0 374 <5.00 4,650 <92.6 82.27
03/03/17 --10.76 -- <1.00 649 1,350 97.0 543 <5.00 6,820 103 83.96
06/15/17 --10.22 -- <10.0 1,730 4,720 274 1,860 205 9,740 219 84.50
11/14/17 --12.54 -- <5.00 404 708 64.5 324 <25.0 3,440 351 82.18
03/21/18 --13.34 -- <5.00 2,430 4,710 638 4,390 <25.0 35,300 1,040 81.38
06/28/18 --12.81 -- <50.0 3,200 9,390 1,170 7,560 <250 49,700 833 81.91
12/20/18 --13.44 -- <5.00 374 144 208 851 <25.0 4,310 790 81.28
09/26/19 --11.92 -- <2.00 7.08 <1.00 22.3 6.76 <1.00 97.2 <47.8 82.80
12/17/19 --12.15 -- <20.0 32.2 18.1 134 558 <10.0 1,850 205 84.44
04/02/20 --12.53 -- <20.0 88.2 32.9 99.6 479 <10.0 1,690 236 84.06
06/22/20 --12.25 --<2.004 11.94 34.34 17.24 86.54 <1.004 3464 139 84.34
12/21/20 --13.64 -- <10.0 47.3 18.7 196 818 <20.0 2,880 338 82.95
03/24/21 --13.57 -- <10.0 65.7 61.2 341 1,600 <20.0 5,780 373 83.02
06/22/21 --13.54 -- <50.0 107 84.9 594 3,790 <100 11,800 650 83.05
09/15/21 --13.22 -- <5.00 20.2 7.46 170 606 <10.0 2,090 309 83.37
01/12/23 --13.37 --<5 <5 <12 <12 51 <12 <125 <1,000 83.22
09/27/23 --12.60 -- <1.00 <1.00 <1.00 48.9 <3.00 <5.00 <500 1206 83.99
12/18/23 -- 13.00 -- <1.00 <1.00 <1.00 26.0 3.15 <5.00 <500 <100 83.59
03/20/24 -- 11.89 -- <1.00 <1.00 <1.00 1.75 <3.00 <5.00 <500 <100 84.70
10/09/24 -- 12.54 -- <1.00 3.58 <1.00 91.5 3.54 6.29 <500 216 84.05
11/14/17 -- -- -- <1.00 145 233 368 1,360 13.7 7,130 688 --
03/21/18 -- 13.84 -- <5.00 410 464 751 4,570 28.9 20,900 934 80.72
06/28/18 -- 13.52 -- <50.0 <50.0 51.4 839 4,320 <250 <20,000 834 81.04
12/20/18 -- 14.00 -- <50.0 1,820 2,110 841 5,560 <250 28,000 1,550 80.56
09/26/19 -- 12.65 -- <8.00 87.7 4.08 88.9 120 <4.00 670 286 81.91
12/17/19 -- 12.81 -- <20.0 113 33.6 238 833 <10.0 2,770 432 82.25
04/02/20 -- 13.14 -- <200 720 2,160 851 6,210 <100 18,600 893 81.92
06/22/20 --12.92 -- <100 164 57.0 519 3,350 <50.0 9,590 926 82.14
12/21/20 -------- ----------------
03/24/21 --14.13 -- <5.00 7.54 25.0 157 668 10.9 2,900 491 80.93
06/22/21 --14.15 -- <0.500 1.49 <0.500 9.37 2.26 1.58 182 139 80.91
200 5 1,000 700 10,000 700 1,000 1,000 --
200 300 3,000 4,000 10,000 700 10,000 10,000 --
MW-4R5
(continued)
MW-9
UDEQ DERR Initial Screening Level
UDEQ DERR Tier 1 Screening Level
MW-5R5
MW-6R
MW-7R
MW-8
fnl_dbs_35508_20241009.xlsx 2 of 3 Stantec Consulting Services Inc.
.
MTBE Benzene Toluene
Ethyl-
benzene
Total
Xylenes Naphthalene
Table 2
Groundwater Monitoring and Analytical Results
7-Eleven Store No. 35508
712 South State Street, Clearfield, Utah
MBTEXN Compounds
(µg/L)Depth to
LNAPL
(feet)
Depth to
Groundwater
(feet)
LNAPL
Thickness
(feet)
TPH-GRO
(µg/L)
Relative
Groundwater
Elevation
(feet)
Sample
Location Date TPH-DRO
(µg/L)
09/15/21 --13.80 -- <0.500 <0.500 <0.500 0.509 <0.500 <1.00 83.9 63.1 81.26
01/12/23 --13.93 --<5 <5 <12 <12 <12 <12 <125 <1,000 81.13
09/27/23 --14.25 -- <1.00 10.2 20.8 214 534 <5.00 2,150 <100 80.81
12/18/23 --13.41 -- <5.00 7.41 <5.00 150 262 <25.0 4,540 3796 81.65
03/20/24 -- 12.54 -- <5.00 17.7 <5.00 255 717 <25.0 2,500 766 82.52
10/09/24 -- 13.23 -- <5.00 35.2 <5.00 375 2,610 <25.0 7,440 670 81.83
09/25/19 -- 12.17 -- <2.00 <1.00 <1.00 <1.00 <1.00 <1.00 <50.0 <49.5 80.96
12/17/19 -- 12.29 -- <2.00 <1.00 <1.00 <1.00 <1.00 <1.00 <50.0 <97.0 82.71
04/02/20 -- 12.61 -- <2.00 <1.00 <1.00 <1.00 <1.00 <1.00 <50.0 <47.4 82.39
06/22/20 -- 12.40 -- <2.00 <1.00 <1.00 <1.00 <1.00 <1.00 <50.0 <47.6 82.60
12/21/20 -- 13.67 -- <0.500 <0.500 <0.500 <0.500 <0.500 <1.00 <50.0 <48.1 81.33
03/24/21 -- 13.57 -- <0.500 <0.500 <0.500 <0.500 <0.500 <1.00 <50.0 98.9 81.43
06/22/21 -- 13.59 -- <0.500 <0.500 <0.500 <0.500 <0.500 <1.00 <50.0 <47.7 81.41
09/14/21 -- 13.17 -- <0.500 <0.500 <0.500 <0.500 <0.500 <1.00 <50.0 <47.6 81.83
01/12/23 -- -- ----
09/27/23 -- 12.55 -- <1.00 <1.00 <1.00 <1.00 <3.00 <5.00 <500 <100 82.45
12/18/23 -- 14.20 -- <1.00 <1.00 <1.00 <1.00 <3.00 <5.00 <500 <200 80.80
03/20/24 -- 12.04 -- <1.00 <1.00 <1.00 <1.00 <3.00 <5.00 <500 110 82.96
10/09/24 -- 12.75 -- <1.00 <1.00 <1.00 <1.00 <3.00 <5.00 <500 <100 82.25
09/25/19 -- 12.06 -- <2.00 <1.00 <1.00 <1.00 <1.00 <1.00 <50.0 109 80.33
12/17/19 -- 12.06 -- <2.00 <1.00 <1.00 <1.00 <1.00 <1.00 <50.0 105 82.20
04/02/20 -- 12.34 -- <2.00 <1.00 <1.00 <1.00 <1.00 <1.00 <50.0 <47.2 81.92
06/22/20 -- 12.25 -- <2.00 <1.00 <1.00 <1.00 <1.00 <1.00 <50.0 <47.6 82.01
12/21/20 -- -- -- -- -- -- -- -- -- -- -- --
03/24/21 -- 13.29 -- <0.500 <0.500 <0.500 <0.500 <0.500 <1.00 <50.0 <47.6 80.97
06/22/21 -- 13.42 -- <0.500 1.63 <0.500 <0.500 <0.500 <1.00 <50.0 <47.3 80.84
09/15/21 -- 13.00 -- <1.00 19.8 <1.00 82.9 <1.00 <2.00 334 84.7 81.26
01/12/23 -- 12.94 -- <5 <5 <12 <12 <12 <12 <125 <1,000 81.32
09/27/23 -- 12.74 -- <1.00 <1.00 <1.00 <1.00 <3.00 <5.00 <500 1006 81.52
12/18/23 -- 12.88 -- <1.00 <1.00 <1.00 <1.00 <3.00 <5.00 <500 1216 81.38
03/20/24 -- 11.73 -- <1.00 <1.00 <1.00 <1.00 <3.00 <5.00 <500 413 82.53
10/09/24 -- 12.59 -- <1.00 <1.00 <1.00 <1.00 <3.00 <5.00 <500 <100 81.67
09/25/19 -- 11.04 -- <2.00 <1.00 <1.00 <1.00 <1.00 <1.00 <50.0 <49.5 85.46
12/17/19 -- 11.65 -- <2.00 <1.00 <1.00 <1.00 <1.00 <1.00 <50.0 <97.2 86.72
04/02/20 -- 12.04 -- <2.00 <1.00 <1.00 <1.00 <1.00 <1.00 <50.0 <47.3 86.33
06/22/20 -- 11.72 -- <2.00 <1.00 <1.00 <1.00 <1.00 <1.00 <50.0 <47.4 86.65
12/21/20 -- 13.07 -- <0.500 <0.500 <0.500 <0.500 <0.500 <1.00 <50.0 <47.9 85.30
03/24/21 -- 13.13 -- <0.500 <0.500 <0.500 <0.500 <0.500 <1.00 <50.0 <47.7 85.24
06/23/21 -- 12.97 -- <0.500 <0.500 <0.500 <0.500 <0.500 <1.00 <50.0 <47.9 85.40
09/15/21 -- 12.82 -- <0.500 <0.500 <0.500 <0.500 <0.500 <1.00 <50.0 <47.8 85.55
01/12/23 -- 13.43 -- <5 <5 <12 <12 <12 <12 <125 <1,000 84.94
09/27/23 -- 11.89 -- <1.00 <1.00 <1.00 <1.00 <3.00 <5.00 <500 1116 86.48
12/18/23 -- 12.62 -- <1.00 <1.00 <1.00 <1.00 <3.00 <5.00 <500 <100 85.75
03/20/24 -- 11.19 -- <1.00 <1.00 <1.00 <1.00 <3.00 <5.00 <500 117 87.18
10/09/24 -- 11.66 -- <1.00 <1.00 <1.00 <1.00 <3.00 <5.00 <500 <100 86.71
200 5 1,000 700 10,000 700 1,000 1,000 --
200 300 3,000 4,000 10,000 700 10,000 10,000 --
01/12/23 <5 <5 <12 <12 <12 <12 <125 <1,000 --
-- -- -- -- -- -- -- -- -- --
09/27/23 <1.00 9.20 19.1 228 510 <5.00 2,1006 <100 --
---- 10% 9% 6% 5%--2%----
12/18/23 <20.0 29.9 12,000 2,590 20,700 115 103,000 2,350 --
---- --1% 30% 10%--126%0%--
03/20/24 <10.1 42.2 8,370 1,630 16,600 <100 72,100 5,160 --
---- -- 35% 16% 12%--145% 74.83%--
10/09/24 <100 <100 2,090 2,250 23,700 <500 70,000 4,630 --
-- -- -- 16% 12% 11% -- -- 8% --
Explanation of Abbreviations:
DERR = Department of Environmental Response and Remediation
LNAPL = light non-aqueous phase liquid (LNAPL) observed
MBTEXN = methyl tert-butyl ether, benzene, toluene, ethylbenzene, total xylenes,MW-1R1 19 4 to 19 100.00
and naphthalene by EPA Method 8260B MW-23 15 5 to 15 98.32
µg/L = micrograms per liter MW-2R1 19 4 to 19 98.15
MTBE = methyl tertiary butyl ether MW-3R1 19 4 to 19 98.94
TPH-GRO = gasoline-range total petroleum hydrocarbons by EPA Method 8260B MW-4R1 19 4 to 19 98.20
TPH-DRO = diesel-range total petroleum hydrocarbons by EPA Method 8015D MW-5R1 19 4 to 19 96.97
UDEQ = Utah Department of Environmental Quality MW-6R1,3 19 4 to 19 97.06
RPD = Relative Percent Difference MW-7R1,3 19 4 to 19 96.40
-- = not observed, measured, analyzed, surveyed or applicable MW-83 19 4 to 19 96.59
< = analyte not detected above the laboratory specified reporting limit MW-92,3 20 5 to 20 95.06
c = corrected depth to water [depth to water - (0.75 x product thickness)MW-102,3 20 4 to 19 95.00
MW-112,3 20 4 to 19 94.26
bold = analytical result exceeds the specified UDEQ DERR Initial Screening Level MW-122,3 20 4 to 19 98.37
bold = analytical result exceeds the specified UDEQ DERR Initial Screening Level and Tier 1 Screening Level
Notes:1= Original 1-inch OD wells MW-1 through MW-7 were replaced by new, 2-inch OD wells MW-1R through MW-7R in October 2016. Former wells MW-1, and MW-3 through
MW-7 were properly abandoned on October 4 through 5, 2016.
2= Well MW-9 was installed on November 14, 2017. Wells MW-10, MW-11, and MW-12 were installed on August 29, 2019.
3= Wells were resurveyed on December 17, 2019.
4= MBTEXN and TPH-GRO analyses were performed outside of holding time due to analyst error; incorrect dilution applied to first analyses within hold time.
5= June 2021 depth to water measurements were collected on 6/22/2021.
6= The same analyte is found in the associated blank.
7= The identification of the analyte is acceptable; the reported value is an estimate.
MW-9
(continued)
Blind Dup
UDEQ DERR Tier 1 Screening Level
RPD
Analytical Results(Collected from
MW-5R)
Blind Dup (Collected from
MW-5R)
Analytical Results
RPD
Blind Dup (Collected from
MW-5R)
Analytical Results
RPD
MW-10
MW-11
MW-125
NOT SAMPLED - COVERED BY DUMPSTER
Blind Dup
UDEQ DERR Initial Screening Level
Blind Dup
RPD
Analytical Results
RPD
Analytical Results
(Collected from
MW-9)
(Collected from
MW-11)
Well
No.
Total Well
Depth
(feet)
Screened
Interval
(feet)
Top of Casing
Elevation
(feet)
fnl_dbs_35508_20241009.xlsx 3 of 3 Stantec Consulting Services Inc.
Reference: Semiannual Groundwater Monitoring Report – 7-Eleven Store No. 35508
712 South State Street, Clearfield, Utah
Facility ID 3000334, Release Site NGN
GRAPHS
fnl_dbs_35508_20241009.xlsx M-2R LNAPL Stantec Consulting Services, Inc.
9
10
11
12
13
14
150
0.5
1
1.5
2
2.5
No
v
-
1
6
Ma
y
-
1
7
No
v
-
1
7
Ma
y
-
1
8
No
v
-
1
8
Ma
y
-
1
9
No
v
-
1
9
Ma
y
-
2
0
Oc
t
-
2
0
Ma
y
-
2
1
Oc
t
-
2
1
Ma
y
-
2
2
Oc
t
-
2
2
Ma
y
-
2
3
Oc
t
-
2
3
Ap
r
-
2
4
Oc
t
-
2
4
De
p
t
h
t
o
G
r
o
u
n
d
w
a
t
e
r
(
f
e
e
t
)
LN
A
P
L
T
h
i
c
k
n
e
s
s
(
f
e
e
t
)
Date
GRAPH 1
7-Eleven Store No. 35508
MW-2R LNAPL Thickness vs. Time
LNAPL Recovery Events MW-2R LNAPL Thickness MW-2R Depth to GW
30
-
d
a
y
C
a
l
C
l
e
a
n
E
v
e
n
t
8.5
9.5
10.5
11.5
12.51
10
100
1000
10000
100000
De
c
-
1
5
Ju
n
-
1
6
De
c
-
1
6
Ju
n
-
1
7
De
c
-
1
7
Ju
n
-
1
8
De
c
-
1
8
Ju
n
-
1
9
De
c
-
1
9
Ju
n
-
2
0
De
c
-
2
0
Ju
n
-
2
1
De
c
-
2
1
Ju
n
-
2
2
De
c
-
2
2
Ju
n
-
2
3
De
c
-
2
3
Ju
n
-
2
4
De
p
t
h
t
o
G
r
o
u
n
d
w
a
t
e
r
(
f
e
e
t
)
Co
n
c
e
n
t
r
a
t
i
o
n
(
µ
g
/
L
)
DATE
GRAPH 2
7-Eleven Store No. 35508
MW-5R Benzene Concentration vs. Time
TSL ISL Benzene Depth to Groundwater Expon. (Benzene)
*Duplicate data used to replace non-detect results from 12/18/23 and 3/20/24.
8.5
9.5
10.5
11.5
12.51
10
100
1000
10000
100000
1000000
De
c
-
1
5
Ju
n
-
1
6
De
c
-
1
6
Ju
n
-
1
7
De
c
-
1
7
Ju
n
-
1
8
De
c
-
1
8
Ju
n
-
1
9
De
c
-
1
9
Ju
n
-
2
0
De
c
-
2
0
Ju
n
-
2
1
De
c
-
2
1
Ju
n
-
2
2
De
c
-
2
2
Ju
n
-
2
3
De
c
-
2
3
Ju
n
-
2
4
De
p
t
h
t
o
G
r
o
u
n
d
w
a
t
e
r
(
f
e
e
t
)
Co
n
c
e
n
t
r
a
t
i
o
n
(
µ
g
/
L
)
DATE
GRAPH 3
7-Eleven Store No. 35508
MW-5R TPH-GRO Concentration vs. Time
TSL ISL TPH-GRO Depth to Groundwater Expon. (TPH-GRO)
*Duplicate data used to replace non-detect result from 10/9/24.
dbs_35508_2024320.xlsx MW-5R Stantec Consulting Services, Inc.
10.0
10.5
11.0
11.5
12.0
12.5
13.0
13.5
14.00.1
1
10
100
1000
10000
No
v
-
1
6
Ma
y
-
1
7
No
v
-
1
7
Ma
y
-
1
8
No
v
-
1
8
Ma
y
-
1
9
No
v
-
1
9
Ma
y
-
2
0
No
v
-
2
0
Ma
y
-
2
1
No
v
-
2
1
Ma
y
-
2
2
No
v
-
2
2
Ma
y
-
2
3
No
v
-
2
3
Ma
y
-
2
4
De
p
t
h
t
o
G
r
o
u
n
d
w
a
t
e
r
(
f
e
e
t
)
Co
n
c
e
n
t
r
a
t
i
o
n
(
µ
g
/
L
)
DATE
GRAPH 4
7-Eleven Store No. 35508
MW-8 Benzene Concentration vs. Time
TSL ISL Benzene Depth to Groundwater Expon. (Benzene)
10.0
10.5
11.0
11.5
12.0
12.5
13.0
13.5
14.01
10
100
1000
10000
100000
No
v
-
1
6
Ma
y
-
1
7
No
v
-
1
7
Ma
y
-
1
8
No
v
-
1
8
Ma
y
-
1
9
No
v
-
1
9
Ma
y
-
2
0
No
v
-
2
0
Ma
y
-
2
1
No
v
-
2
1
Ma
y
-
2
2
No
v
-
2
2
Ma
y
-
2
3
No
v
-
2
3
Ma
y
-
2
4
De
p
t
h
t
o
G
r
o
u
n
d
w
a
t
e
r
(
f
e
e
t
)
Co
n
c
e
n
t
r
a
t
i
o
n
(
µ
g
/
L
)
DATE
GRAPH 5
7-Eleven Store No. 35508
MW-8 TPH-GRO Concentration vs. Time
TSL ISL TPH-GRO Depth to Groundwater Expon. (TPH-GRO)
dbs_35508_2024320.xlsx MW-8 Stantec Consulting Services, Inc.
12.5
13.0
13.5
14.0
14.50.1
1
10
100
1000
10000
No
v
-
1
7
Ma
y
-
1
8
No
v
-
1
8
Ma
y
-
1
9
No
v
-
1
9
Ma
y
-
2
0
No
v
-
2
0
Ma
y
-
2
1
No
v
-
2
1
Ma
y
-
2
2
No
v
-
2
2
Ma
y
-
2
3
No
v
-
2
3
Ma
y
-
2
4
De
p
t
h
t
o
G
r
o
u
n
d
w
a
t
e
r
(
f
e
e
t
)
Co
n
c
e
n
t
r
a
t
i
o
n
(
µ
g
/
L
)
DATE
GRAPH 6
7-Eleven Store No. 35508
MW-9 Benzene Concentration vs. Time
TSL ISL Benzene Depth to Groundwater Expon. (Benzene)
12.5
13.0
13.5
14.0
14.51
10
100
1000
10000
100000
No
v
-
1
7
Ma
y
-
1
8
No
v
-
1
8
Ma
y
-
1
9
No
v
-
1
9
Ma
y
-
2
0
No
v
-
2
0
Ma
y
-
2
1
No
v
-
2
1
Ma
y
-
2
2
No
v
-
2
2
Ma
y
-
2
3
No
v
-
2
3
Ma
y
-
2
4
De
p
t
h
t
o
G
r
o
u
n
d
w
a
t
e
r
(
f
e
e
t
)
Co
n
c
e
n
t
r
a
t
i
o
n
(
µ
g
/
L
)
DATE
GRAPH 7
7-Eleven Store No. 35508
MW-9 TPH-GRO Concentration vs. Time
TSL ISL TPH-GRO Depth to Groundwater Expon. (TPH-GRO)
dbs_35508_2024320.xlsx MW-9 Stantec Consulting Services, Inc.
Reference: Semiannual Groundwater Monitoring Report – 7-Eleven Store No. 35508
712 South State Street, Clearfield, Utah
Facility ID 3000334, Release Site NGN
ATTACHMENT A
Laboratory Analytical Report and Chain-of-Custody Documentation
ANALYTICAL REPORT
October 27, 2024
711 Stantec - Salt Lake City, UT
Sample Delivery Group:L1788199
Samples Received:10/11/2024
Project Number:203720675
Description:7-11 #35508 Clearfield, UT
Report To:Anna Skinner
2890 E Cottonwood Pkwy
Suite 300
Salt Lake City, UT 84121
Entire Report Reviewed By:
October 27, 2024
[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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October 29, 2024
Marty Edwards III
Project Manager
ACCOUNT:PROJECT:SDG:DATE/TIME:PAGE:
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TABLE OF CONTENTS
Cp: Cover Page 1
Tc: Table of Contents 2
Ss: Sample Summary 3
Cn: Case Narrative 6
Sr: Sample Results 7
MW-1R L1788199-01 7
MW-3R L1788199-02 8
MW-4R L1788199-03 9
MW-5R L1788199-04 10
MW-6R L1788199-05 11
MW-7R L1788199-06 12
MW-8 L1788199-07 13
MW-9 L1788199-08 14
MW-10 L1788199-09 15
MW-11 L1788199-10 16
MW-12 L1788199-11 17
DUP-01 L1788199-12 18
TRIP BLANK L1788199-13 19
Qc: Quality Control Summary 20
Volatile Organic Compounds (GC/MS) by Method 8260B 20
Volatile Organic Compounds (GC/MS) by Method 8260B/8260B/OA1 21
Semi-Volatile Organic Compounds (GC) by Method 3511/8015 22
Gl: Glossary of Terms 23
Al: Accreditations & Locations 24
Sc: Sample Chain of Custody 25
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
MW-1R L1788199-01 GW JM 10/09/24 10:45 10/11/24 08:00
Method Batch Dilution Preparation Analysis Analyst Location
date/time date/time
Volatile Organic Compounds (GC/MS) by Method 8260B WG2386634 1 10/22/24 12:32 10/22/24 12:32 JBE Mt. Juliet, TN
Volatile Organic Compounds (GC/MS) by Method 8260B/8260B/OA1 WG2382933 1 10/16/24 04:34 10/16/24 04:34 DYW Mt. Juliet, TN
Semi-Volatile Organic Compounds (GC) by Method 3511/8015 WG2387024 1 10/22/24 16:36 10/24/24 11:02 DMG Mt. Juliet, TN
Collected by Collected date/time Received date/time
MW-3R L1788199-02 GW JM 10/09/24 11:15 10/11/24 08:00
Method Batch Dilution Preparation Analysis Analyst Location
date/time date/time
Volatile Organic Compounds (GC/MS) by Method 8260B WG2386634 1 10/22/24 12:52 10/22/24 12:52 JBE Mt. Juliet, TN
Volatile Organic Compounds (GC/MS) by Method 8260B/8260B/OA1 WG2382933 1 10/16/24 04:55 10/16/24 04:55 DYW Mt. Juliet, TN
Semi-Volatile Organic Compounds (GC) by Method 3511/8015 WG2387024 1 10/22/24 16:36 10/24/24 02:18 MAA Mt. Juliet, TN
Collected by Collected date/time Received date/time
MW-4R L1788199-03 GW JM 10/09/24 13:05 10/11/24 08:00
Method Batch Dilution Preparation Analysis Analyst Location
date/time date/time
Volatile Organic Compounds (GC/MS) by Method 8260B WG2386634 1 10/22/24 13:12 10/22/24 13:12 JBE Mt. Juliet, TN
Volatile Organic Compounds (GC/MS) by Method 8260B/8260B/OA1 WG2382933 1 10/16/24 05:15 10/16/24 05:15 DYW Mt. Juliet, TN
Semi-Volatile Organic Compounds (GC) by Method 3511/8015 WG2387024 1 10/22/24 16:36 10/23/24 13:31 DMG Mt. Juliet, TN
Collected by Collected date/time Received date/time
MW-5R L1788199-04 GW JM 10/09/24 14:40 10/11/24 08:00
Method Batch Dilution Preparation Analysis Analyst Location
date/time date/time
Volatile Organic Compounds (GC/MS) by Method 8260B WG2386634 500 10/22/24 15:29 10/22/24 15:29 JBE Mt. Juliet, TN
Volatile Organic Compounds (GC/MS) by Method 8260B/8260B/OA1 WG2382933 500 10/16/24 08:59 10/16/24 08:59 DYW Mt. Juliet, TN
Semi-Volatile Organic Compounds (GC) by Method 3511/8015 WG2387024 1 10/22/24 16:36 10/23/24 13:51 DMG Mt. Juliet, TN
Collected by Collected date/time Received date/time
MW-6R L1788199-05 GW JM 10/09/24 09:45 10/11/24 08:00
Method Batch Dilution Preparation Analysis Analyst Location
date/time date/time
Volatile Organic Compounds (GC/MS) by Method 8260B WG2386634 1 10/22/24 13:31 10/22/24 13:31 JBE Mt. Juliet, TN
Volatile Organic Compounds (GC/MS) by Method 8260B/8260B/OA1 WG2382933 1 10/16/24 05:35 10/16/24 05:35 DYW Mt. Juliet, TN
Semi-Volatile Organic Compounds (GC) by Method 3511/8015 WG2387024 1 10/22/24 16:36 10/23/24 14:12 DMG Mt. Juliet, TN
Collected by Collected date/time Received date/time
MW-7R L1788199-06 GW JM 10/09/24 12:55 10/11/24 08:00
Method Batch Dilution Preparation Analysis Analyst Location
date/time date/time
Volatile Organic Compounds (GC/MS) by Method 8260B WG2386634 1 10/22/24 13:51 10/22/24 13:51 JBE Mt. Juliet, TN
Volatile Organic Compounds (GC/MS) by Method 8260B/8260B/OA1 WG2382933 1 10/16/24 05:56 10/16/24 05:56 DYW Mt. Juliet, TN
Semi-Volatile Organic Compounds (GC) by Method 3511/8015 WG2387024 1 10/22/24 16:36 10/23/24 14:32 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
MW-8 L1788199-07 GW JM 10/09/24 12:25 10/11/24 08:00
Method Batch Dilution Preparation Analysis Analyst Location
date/time date/time
Volatile Organic Compounds (GC/MS) by Method 8260B WG2386634 1 10/22/24 14:11 10/22/24 14:11 JBE Mt. Juliet, TN
Volatile Organic Compounds (GC/MS) by Method 8260B/8260B/OA1 WG2382933 1 10/16/24 06:16 10/16/24 06:16 DYW Mt. Juliet, TN
Semi-Volatile Organic Compounds (GC) by Method 3511/8015 WG2387024 1 10/22/24 16:36 10/23/24 14:52 DMG Mt. Juliet, TN
Collected by Collected date/time Received date/time
MW-9 L1788199-08 GW JM 10/09/24 14:05 10/11/24 08:00
Method Batch Dilution Preparation Analysis Analyst Location
date/time date/time
Volatile Organic Compounds (GC/MS) by Method 8260B WG2386634 5 10/22/24 15:49 10/22/24 15:49 JBE Mt. Juliet, TN
Volatile Organic Compounds (GC/MS) by Method 8260B/8260B/OA1 WG2382933 5 10/16/24 09:19 10/16/24 09:19 DYW Mt. Juliet, TN
Semi-Volatile Organic Compounds (GC) by Method 3511/8015 WG2387024 1 10/22/24 16:36 10/23/24 15:12 DMG Mt. Juliet, TN
Collected by Collected date/time Received date/time
MW-10 L1788199-09 GW JM 10/09/24 10:15 10/11/24 08:00
Method Batch Dilution Preparation Analysis Analyst Location
date/time date/time
Volatile Organic Compounds (GC/MS) by Method 8260B WG2386634 1 10/22/24 14:30 10/22/24 14:30 JBE Mt. Juliet, TN
Volatile Organic Compounds (GC/MS) by Method 8260B/8260B/OA1 WG2382933 1 10/16/24 06:36 10/16/24 06:36 DYW Mt. Juliet, TN
Semi-Volatile Organic Compounds (GC) by Method 3511/8015 WG2387024 1 10/22/24 16:36 10/23/24 15:32 DMG Mt. Juliet, TN
Collected by Collected date/time Received date/time
MW-11 L1788199-10 GW JM 10/09/24 13:35 10/11/24 08:00
Method Batch Dilution Preparation Analysis Analyst Location
date/time date/time
Volatile Organic Compounds (GC/MS) by Method 8260B WG2386634 1 10/22/24 14:50 10/22/24 14:50 JBE Mt. Juliet, TN
Volatile Organic Compounds (GC/MS) by Method 8260B/8260B/OA1 WG2382933 1 10/16/24 06:57 10/16/24 06:57 DYW Mt. Juliet, TN
Semi-Volatile Organic Compounds (GC) by Method 3511/8015 WG2387024 1 10/22/24 16:36 10/23/24 16:33 DMG Mt. Juliet, TN
Collected by Collected date/time Received date/time
MW-12 L1788199-11 GW JM 10/09/24 09:45 10/11/24 08:00
Method Batch Dilution Preparation Analysis Analyst Location
date/time date/time
Volatile Organic Compounds (GC/MS) by Method 8260B WG2386634 1 10/22/24 15:10 10/22/24 15:10 JBE Mt. Juliet, TN
Volatile Organic Compounds (GC/MS) by Method 8260B/8260B/OA1 WG2382933 1 10/16/24 07:17 10/16/24 07:17 DYW Mt. Juliet, TN
Semi-Volatile Organic Compounds (GC) by Method 3511/8015 WG2387024 1 10/22/24 16:36 10/23/24 15:52 DMG Mt. Juliet, TN
Collected by Collected date/time Received date/time
DUP-01 L1788199-12 GW JM 10/09/24 00:00 10/11/24 08:00
Method Batch Dilution Preparation Analysis Analyst Location
date/time date/time
Volatile Organic Compounds (GC/MS) by Method 8260B WG2386634 100 10/22/24 16:09 10/22/24 16:09 JBE Mt. Juliet, TN
Volatile Organic Compounds (GC/MS) by Method 8260B/8260B/OA1 WG2382933 100 10/16/24 09:39 10/16/24 09:39 DYW Mt. Juliet, TN
Semi-Volatile Organic Compounds (GC) by Method 3511/8015 WG2387024 1 10/22/24 16:36 10/23/24 16:13 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
TRIP BLANK L1788199-13 GW JM 10/09/24 00:00 10/11/24 08:00
Method Batch Dilution Preparation Analysis Analyst Location
date/time date/time
Volatile Organic Compounds (GC/MS) by Method 8260B WG2386634 1 10/22/24 11:14 10/22/24 11:14 JBE Mt. Juliet, TN
Volatile Organic Compounds (GC/MS) by Method 8260B/8260B/OA1 WG2382933 1 10/16/24 03:33 10/16/24 03:33 DYW 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
L1788199-01 MW-1R 3511/8015
L1788199-02 MW-3R 3511/8015
L1788199-03 MW-4R 3511/8015
L1788199-04 MW-5R 3511/8015
L1788199-05 MW-6R 3511/8015
L1788199-07 MW-8 3511/8015
L1788199-08 MW-9 3511/8015
L1788199-09 MW-10 3511/8015
L1788199-10 MW-11 3511/8015
L1788199-11 MW-12 3511/8015
L1788199-12 DUP-01 3511/8015
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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Marty Edwards III
Project Manager
ACCOUNT:PROJECT:SDG:DATE/TIME:PAGE:
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SAMPLE RESULTS - 01
L1788199
MW-1R
Collected date/time: 10/09/24 10:45
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 10/16/2024 04:34 WG2382933
Benzene ND 0.00100 1 10/16/2024 04:34 WG2382933
Toluene ND 0.00100 1 10/16/2024 04:34 WG2382933
Ethylbenzene ND 0.00100 1 10/16/2024 04:34 WG2382933
Xylenes, Total ND 0.00300 1 10/16/2024 04:34 WG2382933
Methyl tert-butyl ether ND 0.00100 1 10/16/2024 04:34 WG2382933
Naphthalene ND 0.00500 1 10/22/2024 12:32 WG2386634
(S) Toluene-d8 103 80.0-120 10/16/2024 04:34 WG2382933
(S) Toluene-d8 105 80.0-120 10/22/2024 12:32 WG2386634
(S) 4-Bromofluorobenzene 96.5 77.0-126 10/16/2024 04:34 WG2382933
(S) 4-Bromofluorobenzene 94.1 77.0-126 10/22/2024 12:32 WG2386634
(S) 1,2-Dichloroethane-d4 98.9 70.0-130 10/16/2024 04:34 WG2382933
(S) 1,2-Dichloroethane-d4 70.7 70.0-130 10/22/2024 12:32 WG2386634
Semi-Volatile Organic Compounds (GC) by Method 3511/8015
Result Qualifier RDL Dilution Analysis Batch
Analyte mg/l mg/l date / time
TPH (GC/FID) High Fraction ND 0.100 1 10/24/2024 11:02 WG2387024
(S) o-Terphenyl 81.1 52.0-156 10/24/2024 11:02 WG2387024
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
L1788199
MW-3R
Collected date/time: 10/09/24 11:15
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 10/16/2024 04:55 WG2382933
Benzene ND 0.00100 1 10/16/2024 04:55 WG2382933
Toluene ND 0.00100 1 10/16/2024 04:55 WG2382933
Ethylbenzene ND 0.00100 1 10/16/2024 04:55 WG2382933
Xylenes, Total ND 0.00300 1 10/16/2024 04:55 WG2382933
Methyl tert-butyl ether ND 0.00100 1 10/16/2024 04:55 WG2382933
Naphthalene ND 0.00500 1 10/22/2024 12:52 WG2386634
(S) Toluene-d8 103 80.0-120 10/16/2024 04:55 WG2382933
(S) Toluene-d8 103 80.0-120 10/22/2024 12:52 WG2386634
(S) 4-Bromofluorobenzene 96.2 77.0-126 10/16/2024 04:55 WG2382933
(S) 4-Bromofluorobenzene 96.0 77.0-126 10/22/2024 12:52 WG2386634
(S) 1,2-Dichloroethane-d4 102 70.0-130 10/16/2024 04:55 WG2382933
(S) 1,2-Dichloroethane-d4 73.1 70.0-130 10/22/2024 12:52 WG2386634
Semi-Volatile Organic Compounds (GC) by Method 3511/8015
Result Qualifier RDL Dilution Analysis Batch
Analyte mg/l mg/l date / time
TPH (GC/FID) High Fraction ND 0.100 1 10/24/2024 02:18 WG2387024
(S) o-Terphenyl 100 52.0-156 10/24/2024 02:18 WG2387024
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
L1788199
MW-4R
Collected date/time: 10/09/24 13:05
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 10/16/2024 05:15 WG2382933
Benzene ND 0.00100 1 10/16/2024 05:15 WG2382933
Toluene ND 0.00100 1 10/16/2024 05:15 WG2382933
Ethylbenzene ND 0.00100 1 10/16/2024 05:15 WG2382933
Xylenes, Total ND 0.00300 1 10/16/2024 05:15 WG2382933
Methyl tert-butyl ether ND 0.00100 1 10/16/2024 05:15 WG2382933
Naphthalene ND 0.00500 1 10/22/2024 13:12 WG2386634
(S) Toluene-d8 104 80.0-120 10/16/2024 05:15 WG2382933
(S) Toluene-d8 108 80.0-120 10/22/2024 13:12 WG2386634
(S) 4-Bromofluorobenzene 95.4 77.0-126 10/16/2024 05:15 WG2382933
(S) 4-Bromofluorobenzene 96.8 77.0-126 10/22/2024 13:12 WG2386634
(S) 1,2-Dichloroethane-d4 98.7 70.0-130 10/16/2024 05:15 WG2382933
(S) 1,2-Dichloroethane-d4 72.4 70.0-130 10/22/2024 13:12 WG2386634
Semi-Volatile Organic Compounds (GC) by Method 3511/8015
Result Qualifier RDL Dilution Analysis Batch
Analyte mg/l mg/l date / time
TPH (GC/FID) High Fraction ND 0.100 1 10/23/2024 13:31 WG2387024
(S) o-Terphenyl 116 52.0-156 10/23/2024 13:31 WG2387024
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
L1788199
MW-5R
Collected date/time: 10/09/24 14:40
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 54.0 500 10/16/2024 08:59 WG2382933
Benzene ND 0.0471 500 10/16/2024 08:59 WG2382933
Toluene 2.45 0.500 500 10/16/2024 08:59 WG2382933
Ethylbenzene 2.53 0.500 500 10/16/2024 08:59 WG2382933
Xylenes, Total 26.4 1.50 500 10/16/2024 08:59 WG2382933
Methyl tert-butyl ether ND 0.0505 500 10/16/2024 08:59 WG2382933
Naphthalene ND 0.500 500 10/22/2024 15:29 WG2386634
(S) Toluene-d8 103 80.0-120 10/16/2024 08:59 WG2382933
(S) Toluene-d8 104 80.0-120 10/22/2024 15:29 WG2386634
(S) 4-Bromofluorobenzene 98.8 77.0-126 10/16/2024 08:59 WG2382933
(S) 4-Bromofluorobenzene 98.1 77.0-126 10/22/2024 15:29 WG2386634
(S) 1,2-Dichloroethane-d4 98.7 70.0-130 10/16/2024 08:59 WG2382933
(S) 1,2-Dichloroethane-d4 73.6 70.0-130 10/22/2024 15:29 WG2386634
Sample Narrative:
L1788199-04 WG2382933, WG2386634: GRO, Benzene, MTBE were reported to the MDL.
L1788199-04 WG2382933, WG2386634: Naphthalene was reported to the MDL.
Semi-Volatile Organic Compounds (GC) by Method 3511/8015
Result Qualifier RDL Dilution Analysis Batch
Analyte mg/l mg/l date / time
TPH (GC/FID) High Fraction 5.01 0.100 1 10/23/2024 13:51 WG2387024
(S) o-Terphenyl 136 52.0-156 10/23/2024 13:51 WG2387024
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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SAMPLE RESULTS - 05
L1788199
MW-6R
Collected date/time: 10/09/24 09:45
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 10/16/2024 05:35 WG2382933
Benzene ND 0.00100 1 10/16/2024 05:35 WG2382933
Toluene ND 0.00100 1 10/16/2024 05:35 WG2382933
Ethylbenzene ND 0.00100 1 10/16/2024 05:35 WG2382933
Xylenes, Total ND 0.00300 1 10/16/2024 05:35 WG2382933
Methyl tert-butyl ether ND 0.00100 1 10/16/2024 05:35 WG2382933
Naphthalene ND 0.00500 1 10/22/2024 13:31 WG2386634
(S) Toluene-d8 107 80.0-120 10/16/2024 05:35 WG2382933
(S) Toluene-d8 105 80.0-120 10/22/2024 13:31 WG2386634
(S) 4-Bromofluorobenzene 98.8 77.0-126 10/16/2024 05:35 WG2382933
(S) 4-Bromofluorobenzene 93.3 77.0-126 10/22/2024 13:31 WG2386634
(S) 1,2-Dichloroethane-d4 98.8 70.0-130 10/16/2024 05:35 WG2382933
(S) 1,2-Dichloroethane-d4 71.7 70.0-130 10/22/2024 13:31 WG2386634
Semi-Volatile Organic Compounds (GC) by Method 3511/8015
Result Qualifier RDL Dilution Analysis Batch
Analyte mg/l mg/l date / time
TPH (GC/FID) High Fraction ND 0.100 1 10/23/2024 14:12 WG2387024
(S) o-Terphenyl 121 52.0-156 10/23/2024 14:12 WG2387024
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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SAMPLE RESULTS - 06
L1788199
MW-7R
Collected date/time: 10/09/24 12:55
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 10/16/2024 05:56 WG2382933
Benzene ND 0.00100 1 10/16/2024 05:56 WG2382933
Toluene ND 0.00100 1 10/16/2024 05:56 WG2382933
Ethylbenzene ND 0.00100 1 10/16/2024 05:56 WG2382933
Xylenes, Total ND 0.00300 1 10/16/2024 05:56 WG2382933
Methyl tert-butyl ether ND 0.00100 1 10/16/2024 05:56 WG2382933
Naphthalene ND 0.00500 1 10/22/2024 13:51 WG2386634
(S) Toluene-d8 103 80.0-120 10/16/2024 05:56 WG2382933
(S) Toluene-d8 103 80.0-120 10/22/2024 13:51 WG2386634
(S) 4-Bromofluorobenzene 93.4 77.0-126 10/16/2024 05:56 WG2382933
(S) 4-Bromofluorobenzene 93.7 77.0-126 10/22/2024 13:51 WG2386634
(S) 1,2-Dichloroethane-d4 102 70.0-130 10/16/2024 05:56 WG2382933
(S) 1,2-Dichloroethane-d4 74.3 70.0-130 10/22/2024 13:51 WG2386634
Semi-Volatile Organic Compounds (GC) by Method 3511/8015
Result Qualifier RDL Dilution Analysis Batch
Analyte mg/l mg/l date / time
TPH (GC/FID) High Fraction 0.349 0.100 1 10/23/2024 14:32 WG2387024
(S) o-Terphenyl 117 52.0-156 10/23/2024 14:32 WG2387024
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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SAMPLE RESULTS - 07
L1788199
MW-8
Collected date/time: 10/09/24 12:25
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 10/16/2024 06:16 WG2382933
Benzene 0.00358 0.00100 1 10/16/2024 06:16 WG2382933
Toluene ND 0.00100 1 10/16/2024 06:16 WG2382933
Ethylbenzene 0.0915 0.00100 1 10/16/2024 06:16 WG2382933
Xylenes, Total 0.00354 0.00300 1 10/16/2024 06:16 WG2382933
Methyl tert-butyl ether ND 0.00100 1 10/16/2024 06:16 WG2382933
Naphthalene 0.00629 0.00500 1 10/22/2024 14:11 WG2386634
(S) Toluene-d8 94.2 80.0-120 10/16/2024 06:16 WG2382933
(S) Toluene-d8 104 80.0-120 10/22/2024 14:11 WG2386634
(S) 4-Bromofluorobenzene 91.2 77.0-126 10/16/2024 06:16 WG2382933
(S) 4-Bromofluorobenzene 103 77.0-126 10/22/2024 14:11 WG2386634
(S) 1,2-Dichloroethane-d4 96.7 70.0-130 10/16/2024 06:16 WG2382933
(S) 1,2-Dichloroethane-d4 78.5 70.0-130 10/22/2024 14:11 WG2386634
Semi-Volatile Organic Compounds (GC) by Method 3511/8015
Result Qualifier RDL Dilution Analysis Batch
Analyte mg/l mg/l date / time
TPH (GC/FID) High Fraction 0.216 0.100 1 10/23/2024 14:52 WG2387024
(S) o-Terphenyl 124 52.0-156 10/23/2024 14:52 WG2387024
1 Cp
2 Tc
3 Ss
4 Cn
5 Sr
6 Qc
7 Gl
8 Al
9 Sc
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SAMPLE RESULTS - 08
L1788199
MW-9
Collected date/time: 10/09/24 14:05
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 7.44 2.50 5 10/16/2024 09:19 WG2382933
Benzene 0.0352 0.00500 5 10/16/2024 09:19 WG2382933
Toluene ND 0.00500 5 10/16/2024 09:19 WG2382933
Ethylbenzene 0.375 0.00500 5 10/16/2024 09:19 WG2382933
Xylenes, Total 2.61 0.0150 5 10/16/2024 09:19 WG2382933
Methyl tert-butyl ether ND 0.00500 5 10/16/2024 09:19 WG2382933
Naphthalene ND 0.0250 5 10/22/2024 15:49 WG2386634
(S) Toluene-d8 94.8 80.0-120 10/16/2024 09:19 WG2382933
(S) Toluene-d8 104 80.0-120 10/22/2024 15:49 WG2386634
(S) 4-Bromofluorobenzene 95.8 77.0-126 10/16/2024 09:19 WG2382933
(S) 4-Bromofluorobenzene 99.1 77.0-126 10/22/2024 15:49 WG2386634
(S) 1,2-Dichloroethane-d4 97.4 70.0-130 10/16/2024 09:19 WG2382933
(S) 1,2-Dichloroethane-d4 71.3 70.0-130 10/22/2024 15:49 WG2386634
Semi-Volatile Organic Compounds (GC) by Method 3511/8015
Result Qualifier RDL Dilution Analysis Batch
Analyte mg/l mg/l date / time
TPH (GC/FID) High Fraction 0.670 0.100 1 10/23/2024 15:12 WG2387024
(S) o-Terphenyl 132 52.0-156 10/23/2024 15:12 WG2387024
1 Cp
2 Tc
3 Ss
4 Cn
5 Sr
6 Qc
7 Gl
8 Al
9 Sc
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SAMPLE RESULTS - 09
L1788199
MW-10
Collected date/time: 10/09/24 10:15
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 10/16/2024 06:36 WG2382933
Benzene ND 0.00100 1 10/16/2024 06:36 WG2382933
Toluene ND 0.00100 1 10/16/2024 06:36 WG2382933
Ethylbenzene ND 0.00100 1 10/16/2024 06:36 WG2382933
Xylenes, Total ND 0.00300 1 10/16/2024 06:36 WG2382933
Methyl tert-butyl ether ND 0.00100 1 10/16/2024 06:36 WG2382933
Naphthalene ND 0.00500 1 10/22/2024 14:30 WG2386634
(S) Toluene-d8 106 80.0-120 10/16/2024 06:36 WG2382933
(S) Toluene-d8 103 80.0-120 10/22/2024 14:30 WG2386634
(S) 4-Bromofluorobenzene 97.1 77.0-126 10/16/2024 06:36 WG2382933
(S) 4-Bromofluorobenzene 94.0 77.0-126 10/22/2024 14:30 WG2386634
(S) 1,2-Dichloroethane-d4 100 70.0-130 10/16/2024 06:36 WG2382933
(S) 1,2-Dichloroethane-d4 74.3 70.0-130 10/22/2024 14:30 WG2386634
Semi-Volatile Organic Compounds (GC) by Method 3511/8015
Result Qualifier RDL Dilution Analysis Batch
Analyte mg/l mg/l date / time
TPH (GC/FID) High Fraction ND 0.100 1 10/23/2024 15:32 WG2387024
(S) o-Terphenyl 130 52.0-156 10/23/2024 15:32 WG2387024
1 Cp
2 Tc
3 Ss
4 Cn
5 Sr
6 Qc
7 Gl
8 Al
9 Sc
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SAMPLE RESULTS - 10
L1788199
MW-11
Collected date/time: 10/09/24 13:35
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 10/16/2024 06:57 WG2382933
Benzene ND 0.00100 1 10/16/2024 06:57 WG2382933
Toluene ND 0.00100 1 10/16/2024 06:57 WG2382933
Ethylbenzene ND 0.00100 1 10/16/2024 06:57 WG2382933
Xylenes, Total ND 0.00300 1 10/16/2024 06:57 WG2382933
Methyl tert-butyl ether ND 0.00100 1 10/16/2024 06:57 WG2382933
Naphthalene ND 0.00500 1 10/22/2024 14:50 WG2386634
(S) Toluene-d8 104 80.0-120 10/16/2024 06:57 WG2382933
(S) Toluene-d8 104 80.0-120 10/22/2024 14:50 WG2386634
(S) 4-Bromofluorobenzene 94.9 77.0-126 10/16/2024 06:57 WG2382933
(S) 4-Bromofluorobenzene 93.9 77.0-126 10/22/2024 14:50 WG2386634
(S) 1,2-Dichloroethane-d4 99.7 70.0-130 10/16/2024 06:57 WG2382933
(S) 1,2-Dichloroethane-d4 73.0 70.0-130 10/22/2024 14:50 WG2386634
Semi-Volatile Organic Compounds (GC) by Method 3511/8015
Result Qualifier RDL Dilution Analysis Batch
Analyte mg/l mg/l date / time
TPH (GC/FID) High Fraction ND 0.100 1 10/23/2024 16:33 WG2387024
(S) o-Terphenyl 143 52.0-156 10/23/2024 16:33 WG2387024
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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SAMPLE RESULTS - 11
L1788199
MW-12
Collected date/time: 10/09/24 09:45
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 10/16/2024 07:17 WG2382933
Benzene ND 0.00100 1 10/16/2024 07:17 WG2382933
Toluene ND 0.00100 1 10/16/2024 07:17 WG2382933
Ethylbenzene ND 0.00100 1 10/16/2024 07:17 WG2382933
Xylenes, Total ND 0.00300 1 10/16/2024 07:17 WG2382933
Methyl tert-butyl ether ND 0.00100 1 10/16/2024 07:17 WG2382933
Naphthalene ND 0.00500 1 10/22/2024 15:10 WG2386634
(S) Toluene-d8 102 80.0-120 10/16/2024 07:17 WG2382933
(S) Toluene-d8 105 80.0-120 10/22/2024 15:10 WG2386634
(S) 4-Bromofluorobenzene 93.6 77.0-126 10/16/2024 07:17 WG2382933
(S) 4-Bromofluorobenzene 95.1 77.0-126 10/22/2024 15:10 WG2386634
(S) 1,2-Dichloroethane-d4 97.9 70.0-130 10/16/2024 07:17 WG2382933
(S) 1,2-Dichloroethane-d4 72.8 70.0-130 10/22/2024 15:10 WG2386634
Semi-Volatile Organic Compounds (GC) by Method 3511/8015
Result Qualifier RDL Dilution Analysis Batch
Analyte mg/l mg/l date / time
TPH (GC/FID) High Fraction ND 0.100 1 10/23/2024 15:52 WG2387024
(S) o-Terphenyl 139 52.0-156 10/23/2024 15:52 WG2387024
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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SAMPLE RESULTS - 12
L1788199
DUP-01
Collected date/time: 10/09/24 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 70.0 50.0 100 10/16/2024 09:39 WG2382933
Benzene ND 0.100 100 10/16/2024 09:39 WG2382933
Toluene 2.09 0.100 100 10/16/2024 09:39 WG2382933
Ethylbenzene 2.25 0.100 100 10/16/2024 09:39 WG2382933
Xylenes, Total 23.7 0.300 100 10/16/2024 09:39 WG2382933
Methyl tert-butyl ether ND 0.100 100 10/16/2024 09:39 WG2382933
Naphthalene ND 0.500 100 10/22/2024 16:09 WG2386634
(S) Toluene-d8 99.2 80.0-120 10/16/2024 09:39 WG2382933
(S) Toluene-d8 105 80.0-120 10/22/2024 16:09 WG2386634
(S) 4-Bromofluorobenzene 97.5 77.0-126 10/16/2024 09:39 WG2382933
(S) 4-Bromofluorobenzene 96.4 77.0-126 10/22/2024 16:09 WG2386634
(S) 1,2-Dichloroethane-d4 99.8 70.0-130 10/16/2024 09:39 WG2382933
(S) 1,2-Dichloroethane-d4 72.5 70.0-130 10/22/2024 16:09 WG2386634
Semi-Volatile Organic Compounds (GC) by Method 3511/8015
Result Qualifier RDL Dilution Analysis Batch
Analyte mg/l mg/l date / time
TPH (GC/FID) High Fraction 4.63 0.100 1 10/23/2024 16:13 WG2387024
(S) o-Terphenyl 137 52.0-156 10/23/2024 16:13 WG2387024
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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SAMPLE RESULTS - 13
L1788199
TRIP BLANK
Collected date/time: 10/09/24 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 10/16/2024 03:33 WG2382933
Benzene ND 0.00100 1 10/16/2024 03:33 WG2382933
Toluene ND 0.00100 1 10/16/2024 03:33 WG2382933
Ethylbenzene ND 0.00100 1 10/16/2024 03:33 WG2382933
Xylenes, Total ND 0.00300 1 10/16/2024 03:33 WG2382933
Methyl tert-butyl ether ND 0.00100 1 10/16/2024 03:33 WG2382933
Naphthalene ND 0.00500 1 10/22/2024 11:14 WG2386634
(S) Toluene-d8 102 80.0-120 10/16/2024 03:33 WG2382933
(S) Toluene-d8 105 80.0-120 10/22/2024 11:14 WG2386634
(S) 4-Bromofluorobenzene 97.4 77.0-126 10/16/2024 03:33 WG2382933
(S) 4-Bromofluorobenzene 101 77.0-126 10/22/2024 11:14 WG2386634
(S) 1,2-Dichloroethane-d4 96.3 70.0-130 10/16/2024 03:33 WG2382933
(S) 1,2-Dichloroethane-d4 77.2 70.0-130 10/22/2024 11:14 WG2386634
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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QUALITY CONTROL SUMMARYWG2386634
Volatile Organic Compounds (GC/MS) by Method 8260B L1788199-01,02,03,04,05,06,07,08,09,10,11,12,13
Method Blank (MB)
(MB) R4137858-3 10/22/24 09:29
MB Result MB Qualifier MB MDL MB RDL
Analyte mg/l mg/l mg/l
Naphthalene U 0.00100 0.00500
(S) Toluene-d8 105 80.0-120
(S) 4-Bromofluorobenzene 95.9 77.0-126
(S) 1,2-Dichloroethane-d4 84.8 70.0-130
Laboratory Control Sample (LCS) • Laboratory Control Sample Duplicate (LCSD)
(LCS) R4137858-1 10/22/24 08:31 • (LCSD) R4137858-2 10/22/24 08:50
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 %%%%%
Naphthalene 0.00500 0.00531 0.00527 106 105 54.0-135 0.756 20
(S) Toluene-d8 106 102 80.0-120
(S) 4-Bromofluorobenzene 102 98.9 77.0-126
(S) 1,2-Dichloroethane-d4 78.8 72.6 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:
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QUALITY CONTROL SUMMARYWG2382933
Volatile Organic Compounds (GC/MS) by Method 8260B/8260B/OA1 L1788199-01,02,03,04,05,06,07,08,09,10,11,12,13
Method Blank (MB)
(MB) R4135542-3 10/16/24 02:49
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
(S) Toluene-d8 100 80.0-120
(S) 4-Bromofluorobenzene 93.4 77.0-126
(S) 1,2-Dichloroethane-d4 99.3 70.0-130
Laboratory Control Sample (LCS)
(LCS) R4135542-1 10/16/24 01:07
Spike Amount LCS Result LCS Rec. Rec. Limits LCS Qualifier
Analyte mg/l mg/l %%
Benzene 0.00500 0.00542 108 70.0-123
Toluene 0.00500 0.00515 103 79.0-120
Ethylbenzene 0.00500 0.00507 101 79.0-123
Xylenes, Total 0.0150 0.0155 103 79.0-123
Methyl tert-butyl ether 0.00500 0.00498 99.6 68.0-125
(S) Toluene-d8 101 80.0-120
(S) 4-Bromofluorobenzene 98.1 77.0-126
(S) 1,2-Dichloroethane-d4 103 70.0-130
Laboratory Control Sample (LCS)
(LCS) R4135542-2 10/16/24 01:48
Spike Amount LCS Result LCS Rec. Rec. Limits LCS Qualifier
Analyte mg/l mg/l %%
TPH (GC/MS) Low Fraction 5.00 5.87 117 66.0-132
(S) Toluene-d8 90.9 80.0-120
(S) 4-Bromofluorobenzene 115 77.0-126
(S) 1,2-Dichloroethane-d4 105 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:
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QUALITY CONTROL SUMMARYWG2387024
Semi-Volatile Organic Compounds (GC) by Method 3511/8015 L1788199-01,02,03,04,05,06,07,08,09,10,11,12
Method Blank (MB)
(MB) R4136813-1 10/23/24 20:39
MB Result MB Qualifier MB MDL MB RDL
Analyte mg/l mg/l mg/l
TPH (GC/FID) High Fraction U 0.0247 0.100
(S) o-Terphenyl 106 52.0-156
Laboratory Control Sample (LCS) • Laboratory Control Sample Duplicate (LCSD)
(LCS) R4136813-2 10/23/24 20:59 • (LCSD) R4136813-3 10/23/24 21:19
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) High Fraction 1.50 2.03 2.07 135 138 50.0-150 1.95 20
(S) o-Terphenyl 124 130 52.0-156
1 Cp
2 Tc
3 Ss
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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
MDL Method Detection Limit.
ND Not detected at the Reporting Limit (or MDL where applicable).
RDL 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.
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
The remainder of this page intentionally left blank, there are no qualifiers applied to this SDG.
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Pace Analytical National 12065 Lebanon Rd Mount Juliet, TN 37122
Alabama 40660 Nebraska NE-OS-15-05
Alaska 17-026 Nevada TN000032021-1
Arizona AZ0612 New Hampshire 2975
Arkansas 88-0469 New Jersey–NELAP TN002
California 2932 New Mexico ¹TN00003
Colorado TN00003 New York 11742
Connecticut PH-0197 North Carolina Env375
Florida E87487 North Carolina ¹DW21704
Georgia NELAP North Carolina ³41
Georgia ¹923 North Dakota R-140
Idaho TN00003 Ohio–VAP CL0069
Illinois 200008 Oklahoma 9915
Indiana C-TN-01 Oregon TN200002
Iowa 364 Pennsylvania 68-02979
Kansas E-10277 Rhode Island LAO00356
Kentucky ¹ ⁶KY90010 South Carolina 84004002
Kentucky ²16 South Dakota n/a
Louisiana AI30792 Tennessee ¹ ⁴2006
Louisiana LA018 Texas T104704245-20-18
Maine TN00003 Texas ⁵LAB0152
Maryland 324 Utah TN000032021-11
Massachusetts M-TN003 Vermont VT2006
Michigan 9958 Virginia 110033
Minnesota 047-999-395 Washington C847
Mississippi TN00003 West Virginia 233
Missouri 340 Wisconsin 998093910
Montana CERT0086 Wyoming A2LA
A2LA – ISO 17025 1461.01 AIHA-LAP,LLC EMLAP 100789
A2LA – ISO 17025 ⁵1461.02 DOD 1461.01
Canada 1461.01 USDA P330-15-00234
EPA–Crypto TN00003
ACCREDITATIONS & LOCATIONS
¹ Drinking Water ² Underground Storage Tanks ³ Aquatic Toxicity ⁴ Chemical/Microbiological ⁵ Mold ⁶ Wastewater n/a Accreditation not applicable
* 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.
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