DERR-2025-004597

AECOM
756 E Winchester St, Ste 400
Murray, UT 84107
aecom.com
June 18, 2025
AECOM Project No. 60746179
Quinn Walker
Utah Department of Environmental Quality
Division of Environmental Response and Remediation (DERR)
195 North 1950 West
Salt Lake City, UT 84116
Subject: First Semi-Annual 2025 Groundwater Monitoring Report
Dear Mr. Walker,
On behalf of Chevron Environmental Management Company (CEMC), AECOM is pleased to submit this
Groundwater Monitoring Report for the following facility:
Former Chevron Station Number Case Number Location
71887 FS ID# 1200035
Release Site FME
2003 South Washington
Boulevard, Ogden, Utah
Work Performed During This Reporting Period (Semi-Annual 2025)
Semi-annual groundwater monitoring activities were conducted by AECOM on May 6, 2025 in response to a
November 26, 2024 letter from the Utah Department of Environmental Quality Division of Environmental Response
and Remediation (UDEQ DERR) requesting additional semi-annual groundwater monitoring (DERR 2024). As
verbally discussed in a meeting on March 20, 2025 only two wells are required to be sampled during these events,
MW-23 and MW-24.
Groundwater Monitoring
The monitoring well network at the site currently consists of four onsite wells (MW-2 through MW-4, MW-6), and
seven offsite wells (MW-11, MW-12, MW-23 through MW-27). The site location map and site plan are included
as Figures 1 and 2, respectively.
Prior to gauging, well plugs were removed, allowing the wells to equilibrate to atmospheric pressure. An electronic
interface probe was then used to measure the depth to Light Non-Aqueous Phase Liquid (LNAPL) and/or
groundwater at each monitoring point. LNAPL was not encountered in any of the wells during this sampling event.
Following gauging activities, wells MW-23 and MW-24 were purged and sampled using low flow sampling
methods. Field parameters were recorded periodically during purging (pH, electrical conductivity, dissolved
oxygen, oxidation-reduction potential, temperature, and turbidity), and samples were collected after field
parameters reached stable conditions. Groundwater purging and sampling was conducted by a Utah-Certified soil
and groundwater sampler. A copy of the field forms are included in Attachment A.
Groundwater samples were submitted to Eurofins Denver, in Arvada, CO under standard chain-of-custody
protocols. Samples collected from the monitoring wells were submitted for laboratory analysis of methyl-tert-
butyl ether (MTBE), benzene, toluene, ethylbenzene, xylenes, and naphthalene (MBTEXN) by United States
Environmental Protection Agency (USEPA) Method 8260D; total petroleum hydrocarbons as gasoline range

2
organics (TPH-GRO) by USEPA Method 8015D; and total petroleum hydrocarbons as diesel range organics
(TPH-DRO) with silica gel cleanup (SGC) by USEPA Method 3630C/8015D.
Groundwater gauging data and analytical results for this event are summarized in Table 1. The groundwater
elevation contour map is presented on Figure 3. The groundwater analytical map is presented on Figure 4. A
copy of the laboratory analytical report and chain-of-custody documentation is provided as Attachment B.
Groundwater Gradient and Flow Direction
The groundwater flow direction at the site is to the southwest; however, only 2 wells (MW-23 and MW-24) were
gauged during this event. A full round of well gauging will be conducted during the next semi-annual event.
Laboratory Analytical Results
Analytical results for groundwater samples collected are summarized below and compared against DERR
Leaking Underground Storage Tanks (LUST) initial screening levels (ISLs) or Tier 1 Screening Levels (SLs).
Note, both MW-23 and MW-24 are off-site wells, therefore should be compared to ISLs.
Constituents of concern were detected at concentrations exceeding applicable criteria, as summarized below:
 Benzene was detected above the ISL of 0.005 milligrams per liter (mg/L) in the groundwater samples at
MW-23 (0.0510 mg/L) and MW-24 (0.0067 J mg/L).
 TPH-GRO was detected above the ISL of 1.0 mg/L in the groundwater samples at MW-23 (4.1 mg/L)
and MW-24 (1.1 mg/L).
Based on the detected benzene and TPH-GRO at MW-23 and MW-24, the dissolved phase concentrations
appear stable to decreasing when evaluating on a seasonal basis (fall to fall and spring to spring).
Conclusions
The May 2025 groundwater monitoring and sampling results are summarized as follows:
 No LNAPL was observed in any of the wells.
 MW-23: Benzene and TPH-GRO were detected at concentrations exceeding the Utah LUST ISLs.
 MW-24: Benzene and TPH-GRO were detected at concentrations exceeding the Utah LUST ISLs.
 AECOM will perform one more round of semi-annual monitoring of select constituents at MW-23 and MW-
24. The next routine groundwater monitoring event is scheduled for October 23, 2025.
Remarks/Signatures
The interpretations in this report represent AECOM’s professional opinions and are based, in part, on the
information supplied by previous consultants, AECOM field personnel, and laboratory. These opinions are based
on currently available information and are arrived at in accordance with currently accepted hydrogeologic and
engineering practices at the site location and time of this report preparation. Other than this, no warranty is implied
or intended.

AECOM appreciates the opportunity to provide you with assistance on this project. If you have any questions,
please contact me at [phone].

3
Yours sincerely,

Wil Pineda, P.E.
Project Manager
[e-mail]
Attachments:
Figure 1 – Site Location Map
Figure 2 – Site Plan
Figure 3 – Groundwater Elevation Contour Map, May 6, 2025
Figure 4 – Groundwater Analytical Map, May 6, 2025
Table 1 – Summary of Groundwater Analytical and Elevation Data
Attachment A – Groundwater Monitoring Field Forms
Attachment B – Laboratory Analytical Report

References:
Arcadis 2023. Corrective Action Completion Report and Closure Request. April 4

DERR. 2024. Additional Sampling Requirements, Chevron #71887, located at 2003 South Washington
Boulevard, Ogden, Utah, Facility Identification No. 1200035, Release Site FME. November 26.

PROJECT
LOCATION
FIGURE
Approximate Scale: 1 in. = 2,000 ft.
0 2,000'4,000'
SITE LOCATION MAP
MAP SOURCE: BASE MAP USGS 7.5. MIN. TOPO. QUAD., OGDEN, UT 2017
FORMER CHEVRON STATION NO. 7-1887
2003 SOUTH WASHINGTON BOULEVARD
OGDEN, UTAH
N
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EVEREAL-ESTATE, LLC.
010430011
EVEREAL-ESTATE LLC.
010430012
PROPERTY RESERVE, INC.
011050002
JENSAR, LLC.
010440036
CORP OF THE PRES.
BISHOP OF THE
CHURCH OF JESUS
010440035
FORMER SOIL
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SITE PLAN
APPROXIMATE SCALE : 1 in. = 40 ft.
0 60'120'
N
NOTES:
1.BASE MAP PROVIDED BY LEIDOS, INC., DATED 6/14/2018,
AT A SCALE OF 1" = 40'.
2.ALL SITE FEATURES AND LOCATIONS ARE APPROXIMATE.2
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FORMER CHEVRON STATION NO. 7-1887
2003 SOUTH WASHINGTON BOULEVARD
OGDEN, UTAH
FIGURE
MW-2
LEGEND:
MONITORING WELL LOCATION
DESTROYED WELL LOCATION
SOIL BORING / GRAB GROUNDWATER
SOIL BORING
SITE BOUNDARY
MW-1
BH-1
SB-1A
OFFSITE BOUNDARY
APPROXIMATE LOCATION OF PFBs (JUNE 2021)
EVEREAL-ESTATE, LLC.
010430011
EVEREAL-ESTATE LLC.
010430012
PROPERTY RESERVE, INC.
011050002
JENSAR, LLC.
010440036
CORP OF THE PRES.
BISHOP OF THE
CHURCH OF JESUS
010440035
FORMER SOIL
VAPOR
EXTRACTION
SYSTEM
LOCATIONFORMER UST
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EVEREAL-ESTATE, LLC.
010430011
EVEREAL-ESTATE LLC.
010430012
PROPERTY RESERVE, INC.
011050002
JENSAR, LLC.
010440036
CORP OF THE PRES.
BISHOP OF THE
CHURCH OF JESUS
010440035
FORMER SOIL
VAPOR
EXTRACTION
SYSTEM
LOCATIONFORMER UST
LOCATIONS
FORMER
DISPENSER
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FORMER
STATION
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MW-6
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MW-24
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MW-25
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MW-11
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MW-12
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MW-5
MW-21
MW-7
MW-22
MW-20
MW-19
MW-15
MW-13 MW-14
MW-1
GROUNDWATER ELEVATION
CONTOUR MAP
MAY 6, 2025
APPROXIMATE SCALE : 1 in. = 40 ft.
0 40'80'
N
NOTES:
1. BASE MAP PROVIDED BY LEIDOS, INC., DATED
6/14/2018, AT A SCALE OF 1" = 40'.
2. ALL SITE FEATURES AND LOCATIONS ARE
APPROXIMATE.
3. CONTOUR LINES ARE ESTIMATED.
(NC)
(88.29)
MW-2
(NM)
LEGEND:
MONITORING WELL LOCATION
DESTROYED WELL LOCATION
GROUNDWATER ELEVATION NOT CALCULATED DUE
TO LACK OF LAND SURVEY DATA FOR TOP OF CASING.
GROUNDWATER ELEVATION (FEET)
GROUNDWATER ELEVATION CONTOUR (BASED ON HISTORICAL KNOWLEDGE)
APPROXIMATE GROUNDWATER FLOW DIRECTION
NOT MEASURED
WELL NOT USED FOR CONTOURING
SITE BOUNDARY
OFFSITE BOUNDARY
MW-1
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OGDEN, UTAH
FIGURE
*
0.00
3
FT/F
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MW-26 MW-27
EVEREAL-ESTATE, LLC.
010430011
EVEREAL-ESTATE LLC.
010430012
PROPERTY RESERVE, INC.
011050002
JENSAR, LLC.
010440036
CORP OF THE PRES.
BISHOP OF THE
CHURCH OF JESUS
010440035
FORMER SOIL
VAPOR
EXTRACTION
SYSTEM
LOCATIONFORMER UST
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FORMER
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LOCATION
FORMER
STATION
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MW-20
MW-3
MW-2
MW-4
MW-23
MW-24
MW-25
MW-11
MW-12
SB-1A
SB-4A
SB-3A
SB-2A
BH-2
BH-1
BH-5
BH-3 BH-4
BH-7
MW-19
MW-10
MW-16
MW-17
MW-18
MW-9
MW-8
MW-22
MW-21
MW-7
MW-1
MW-13 MW-14 MW-15
MW-6
SB-6A
MW-5 SB-5A
GROUNDWATER ANALYTICAL DATA
MAY 6, 2025
APPROXIMATE SCALE : 1 in. = 40 ft.
0 60'120'
N
NOTES:
1. BASE MAP PROVIDED BY LEIDOS, INC., DATED 6/14/2018, AT A SCALE OF 1" = 40'.
2. ALL SITE FEATURES AND LOCATIONS ARE APPROXIMATE.
3. RESULTS IN MILLIGRMS PER KILOGRAM (mg/kg)
4. J = ESTIMATED VALUE
5. BOLD = EXCEEDS DERR ISLs
6. < = NOT DETECTED AT OR ABOVE METHOD DETECTION LIMIT
7. SHADED CELL RESULTS EXCEED RBCA TIER 1SLs
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FIGURE
MW-2
LEGEND:
MONITORING WELL LOCATION
DESTROYED WELL LOCATION
SOIL BORING / GRAB GROUNDWATER
SOIL BORING
SITE BOUNDARY
MW-1
BH-1
SB-1A
OFFSITE BOUNDARY 4
Table 1
Current and Historical Groundwater Gauging and Analytical Results
Former Chevron Station No. 7-1887
2003 S. Washington Boulevard, Ogden, Utah
Sample Location Date Benzene Toluene Ethyl-Benzene Total Xylenes Naphthalene MTBE Total TPH TPH-GRO
TPH-DRO
w/o SGC
TPH-DRO
w/SGC TOC DTW
Product
Thickness GWE Notes
MM/DD/YY (mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(feet)1 (feet btoc)(feet)(feet)
0.005 1.0 0.7 10 0.700 0.200 -- 1 1 1
0.300 3.0 4 10 0.700 0.200 -- 10 10 10
BH-1 09/08/15 <0.0005 <0.0005 <0.0005 <0.0005 <0.001 <0.0005 -- <0.022 -- <0.046 -- ------
BH-2 09/08/15 <0.0005 <0.0005 <0.0005 <0.0005 <0.001 <0.0005 -- <0.022 -- <0.045 -- -- -- --
BH-3 09/09/15 0.33 0.012 0.004 0.066 0.053 <0.003 --4.4 -- 0.840 -- -- -- --
BH-4 09/09/15 0.012 0.003 0.002 0.015 0.023 <0.0005 --1.8 -- 0.210 -- -- -- --
BH-5 09/09/15 <0.0005 <0.0005 <0.0005 <0.0005 <0.001 <0.0005 -- <0.022 -- 0.260 -- -- -- --
MW-1 03/02/89 2.7 3.9 1.6 12 -- -- 36 -- -- -- 99.52 9.12 0.00 90.40
MW-1 02/08/90 1.1 0.41 1.3 11 -- -- 36 -- -- -- 99.52 -- -- --
MW-1 11/29/90 0.073 ND 0.232 2.35 -- -- 15.8 -- -- -- 99.52 -- -- --
MW-1 04/23/91 0.115 0.0115 0.0325 0.894 -- -- 15.7 -- -- -- 99.52 10.45 0.00 89.07
MW-1 07/11/91 0.0062 ND 0.0068 0.289 -- -- 5.39 -- -- -- 99.52 9.41 0.00 90.11
MW-1 10/01/91 0.0032 ND ND 0.0655 -- -- 2.12 -- -- -- 99.39 9.61 0.00 89.78
Surveyed 10/91
MW-1 01/01/92 ND ND 0.009 0.161 -- -- 0.460 -- -- -- 99.39 9.00 0.00 90.39
MW-1 04/01/92 ND ND ND ND -- -- 0.630 -- -- -- 99.39 9.77 0.00 89.62
MW-1 07/01/92 ND ND 0.0033 0.0495 -- -- ND -- -- -- 99.39 9.23 0.00 90.16
MW-1 10/01/92 0.0136 0.012 ND 0.0304 -- -- 0.247 -- -- -- 99.39 10.08 0.00 89.31
MW-1 01/21/93 ND ND 0.003 0.019 -- -- 0.870 -- -- -- 99.39 9.72 0.00 89.67
MW-1 04/26/93 ND 0.0006 0.0009 0.005 -- -- 0.340 -- -- -- 99.39 8.69 0.00 90.70
MW-1 07/20/93 0.001 ND 0.0005 0.009 -- -- 0.250 -- -- -- 99.39 9.13 0.00 90.26
MW-1 10/27/93 ND 0.0007 0.0006 0.003 -- -- 0.100 -- -- -- 99.39 9.74 0.00 89.65
MW-1 01/26/94 ND ND 0.001 0.004 -- -- 0.230 -- -- -- 99.39 9.38 0.00 90.01
MW-1 04/29/94 ND ND ND ND -- -- ND -- -- -- 99.39 8.12 0.00 91.27
MW-1 07/28/94 ND ND ND 0.001 -- -- 0.081 -- -- -- 99.39 9.64 0.00 89.75
MW-1 10/11/94 ND 0.0013 ND 0.0013 -- -- 0.085 -- -- -- 99.39 9.71 0.00 89.68
MW-1 01/20/95 ND ND ND ND -- -- 0.063 -- -- -- 99.39 8.98 0.00 90.41
MW-1 04/21/95 ND 0.0007 ND ND -- -- ND -- -- -- 99.39 8.93 0.00 90.46
MW-1 07/25/95 ND ND ND ND -- -- ND -- -- -- 99.39 9.73 0.00 89.66
MW-1 07/02/96 ND ND ND ND -- -- ND -- -- -- 99.39 9.60 0.00 89.79
MW-1 08/11/97 ND ND ND 0.003 ND ND 0.045 -- -- -- 99.39 8.67 0.00 90.72
MW-1 08/31/98 ND ND ND ND ND ND ND -- -- -- 99.39 9.17 0.00 90.22
MW-1 04/21/99 ND ND ND 0.00052 ND ND 0.230 -- -- -- 99.39 8.91 0.00 90.48
MW-1 08/12/99 <0.0005 <0.0005 <0.0005 <0.0005 <0.035 <0.002 <0.00050 -- -- -- 99.39 9.18 0.00 90.21
MW-1 11/10/99 -- -- -- -- -- -- -- -- -- -- 99.39 9.52 0.00 89.87
MW-1 03/07/00 <0.0005 <0.0005 <0.0005 <0.0005 <0.035 <0.0025 <0.050 -- -- -- 99.39 9.10 0.00 90.29
MW-1 05/17/00 -- -- -- -- -- -- -- -- -- -- 99.39 9.66 0.00 89.73
MW-1 08/10/00 -- -- -- -- -- -- -- -- -- -- 99.39 9.72 0.00 89.67
MW-1 11/08/00 <0.002 <0.002 <0.002 <0.006 <0.002 <0.002 <0.500 -- -- -- 99.39 10.16 0.00 89.23
MW-1 02/06/01 <0.002 <0.002 <0.002 <0.006 <0.002 <0.002 <0.500 -- -- -- 99.39 10.46 0.00 88.93
MW-1 05/01/01 -- -- -- -- -- -- -- -- -- -- 99.39 9.93 0.00 89.46
MW-1 08/22/01 -- -- -- -- -- -- -- -- -- -- 99.39 9.80 0.00 89.59
MW-1 11/15/01 -- -- -- -- -- -- -- -- -- -- 99.39 10.58 0.00 88.81
MW-1 02/25/02 -- -- -- -- -- -- -- -- -- -- 99.39 10.27 0.00 89.12
MW-1 05/21/02 -- -- -- -- -- -- -- -- -- -- 99.39 9.20 0.00 90.19
MW-1 08/20/02 -- -- -- -- -- -- -- -- -- -- 99.39 9.70 0.00 89.69
MW-1 11/05/02 -- -- -- -- -- -- -- -- -- -- 99.39 10.07 0.00 89.32
MW-1 03/19/03 <0.0005 <0.0005 <0.0005 <0.0005 <0.001 <0.0025 <0.050 -- -- -- 99.39 9.96 0.00 89.43
MW-1 06/17/03 -- -- -- -- -- -- -- -- -- -- 99.39 9.53 0.00 89.86
MW-1 09/30/03 -- -- -- -- -- -- -- -- -- -- 99.39 9.88 0.00 89.51
MW-1 11/25/03 -- -- -- -- -- -- -- -- -- -- 99.39 9.96 0.00 89.43
MW-1 12/01/07
DERR ISL
RBCA Tier 1 SL
WELL WAS DESTROYED DURING DEMOLITION ACTIVITIES BY THE OFFSITE PROPERTY OWNERS
Not Applicable
71887 Tables 1SA25 2025_V0 1/14
Table 1
Current and Historical Groundwater Gauging and Analytical Results
Former Chevron Station No. 7-1887
2003 S. Washington Boulevard, Ogden, Utah
Sample Location Date Benzene Toluene Ethyl-Benzene Total Xylenes Naphthalene MTBE Total TPH TPH-GRO
TPH-DRO
w/o SGC
TPH-DRO
w/SGC TOC DTW
Product
Thickness GWE Notes
MM/DD/YY (mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(feet)1 (feet btoc)(feet)(feet)
0.005 1.0 0.7 10 0.700 0.200 -- 1 1 1
0.300 3.0 4 10 0.700 0.200 -- 10 10 10
DERR ISL
RBCA Tier 1 SL Not Applicable
MW-2 03/02/89 0.23 0.22 0.12 0.77 -- -- 4.2 -- -- -- 99.01 8.65 0.00 90.36
MW-2 03/02/89 0.23 0.22 0.12 0.77 -- -- 4.2 -- -- -- 99.01 8.65 0.00 90.36
MW-2 01/26/90 0.081 0.04 ND 0.12 -- -- 4.2 -- -- -- 99.01 9.85 0.00 89.16
MW-2 11/29/90 0.056 ND ND 0.103 -- -- ND -- -- -- 99.01 9.85 0.00 89.16
MW-2 04/23/91 0.0262 ND ND 0.0457 -- -- 3.54 -- -- -- 99.01 8.84 0.00 90.17
MW-2 07/11/91 ND ND ND ND -- -- 0.251 -- -- -- 99.01 9.00 0.00 90.01
MW-2 10/01/91 ND ND ND ND -- -- ND -- -- -- 99.02 9.80 0.00 89.22
Surveyed 10/91
MW-2 01/01/92 ND ND ND 0.01 -- -- ND -- -- -- 99.02 9.28 0.00 89.74
MW-2 04/01/92 ND ND ND ND -- -- ND -- -- -- 99.02 9.36 0.00 89.66
MW-2 07/01/92 0.0018 0.0089 0.0065 0.0953 -- -- ND -- -- -- 99.02 9.41 0.00 89.61
MW-2 10/01/92 ND ND ND ND -- -- ND -- -- -- 99.02 9.77 0.00 89.25
MW-2 04/26/93 ND 0.002 0.004 0.051 -- -- 0.470 -- -- -- 99.02 8.59 0.00 90.43
MW-2 07/20/93 0.006 0.007 0.018 0.11 -- -- 0.600 -- -- -- 99.02 8.94 0.00 90.08
MW-2 10/27/93 0.003 0.014 0.013 0.15 -- -- 1.2 -- -- -- 99.02 9.39 0.00 89.63
MW-2 01/26/94 ND 0.0007 0.002 0.014 -- -- 0.081 -- -- -- 99.02 9.57 0.00 89.45
MW-2 04/29/94 ND ND ND 0.002 -- -- ND -- -- -- 99.02 8.52 0.00 90.50
MW-2 07/28/94 ND 0.0022 0.017 0.065 -- -- 0.58 -- -- -- 99.02 9.61 0.00 89.41
MW-2 10/11/94 0.011 0.0072 0.006 0.21 -- -- 1.7 -- -- -- 99.02 9.57 0.00 89.45
MW-2 01/20/95 0.011 0.0035 0.0091 0.13 -- -- 0.84 -- -- -- 99.02 8.66 0.00 90.36
MW-2 04/21/95 ND 0.0033 0.0013 0.019 -- -- 0.37 -- -- -- 99.02 8.39 0.00 90.63
MW-2 07/25/95 ND 0.0059 0.058 0.33 -- -- 4 -- -- -- 99.02 9.24 0.00 89.78
MW-2 07/02/96 0.023 ND 0.021 0.094 -- -- 4.2 -- -- -- 99.02 9.13 0.00 89.89
MW-2 08/11/97 ND ND ND ND ND ND 0.077 -- -- -- 99.02 8.61 0.00 90.41
MW-2 08/31/98 0.0019 ND ND ND 0.042 0.011 0.16 -- -- -- 99.02 8.70 0.00 90.32
MW-2 04/21/99 0.0011 ND 0.00055 0.0019 ND ND 0.075 -- -- -- 99.02 8.44 0.00 90.58
MW-2 08/12/99 0.00743 <0.0005 0.000838 0.00336 <0.035 <0.002 0.38 -- -- -- 99.02 8.69 0.00 90.33
MW-2 11/10/99 -- -- -- -- -- -- -- -- -- -- 99.02 9.03 0.00 89.99
MW-2 03/07/00 0.00156 <0.0005 0.000556 <0.0005 <0.035 <0.0025 0.264 -- -- -- 99.02 8.68 0.00 90.34
MW-2 05/17/00 -- -- -- -- -- -- -- -- -- -- 99.02 9.20 0.00 89.82
MW-2 08/10/00 -- -- -- -- -- -- -- -- -- -- 99.02 9.22 0.00 89.80
MW-2 11/08/00 0.0031 0.0021 <0.002 0.0074 0.0032 <0.002 <0.500 -- -- -- 99.02 9.70 0.00 89.32
MW-2 02/06/01 0.0034 <0.002 <0.002 <0.006 <0.002 <0.002 <0.500 -- -- -- 99.02 10.02 0.00 89.00
MW-2 05/01/01 -- -- -- -- -- -- -- -- -- -- 99.02 9.49 0.00 89.53
MW-2 08/22/01 -- -- -- -- -- -- -- -- -- -- 99.02 9.33 0.00 89.69
MW-2 11/15/01 -- -- -- -- -- -- -- -- -- -- 99.02 10.14 0.00 88.88
MW-2 02/25/02 -- -- -- -- -- -- -- -- -- -- 99.02 9.88 0.00 89.14
MW-2 05/21/02 -- -- -- -- -- -- -- -- -- -- 99.02 8.89 0.00 90.13
MW-2 08/20/02 0.0035 <0.0005 <0.0005 <0.0015 <0.001 <0.0025 0.22 -- -- -- 99.02 9.21 0.00 89.81
MW-2 11/05/02 0.0016 <0.0005 <0.0005 <0.0015 <0.001 <0.0025 0.18 -- -- -- 99.02 9.55 0.00 89.47
MW-2 03/19/03 <0.0005 <0.0005 <0.0005 <0.0015 <0.001 <0.0025 <0.050 -- -- -- 99.02 9.05 0.00 89.97
MW-2 06/17/03 ND ND ND ND ND ND ND -- -- -- 99.02 8.91 0.00 90.11
MW-2 09/30/03 <0.0005 <0.0005 <0.0005 <0.0005 <0.001 <0.0005 <0.050 -- -- -- 99.02 9.40 0.00 89.62
MW-2 11/25/03 <0.0005 <0.0005 <0.0005 0.0005 <0.001 <0.0005 0.12 -- -- -- 99.02 9.51 0.00 89.51
MW-2 12/13/07 <0.0005 <0.0005 <0.0005 <0.0005 0.002 <0.0005 -- 0.42 -- 0.18 99.02 10.21 0.00 88.81
MW-2 06/03/08 <0.0005 <0.0005 <0.0005 <0.0005 0.046 <0.0005 --1.1 0.45 -- 99.02 10.41 0.00 88.61
MW-2 12/01/08 <0.0005 <0.0005 <0.0005 <0.0005 <0.001 <0.0005 -- <0.050 0.48 -- 99.02 11.65 0.00 87.37
MW-2 06/01/09 <0.0005 <0.0005 <0.0005 <0.0005 <0.001 <0.0005 -- 0.077 0.23 -- 99.02 11.18 0.00 87.84
MW-2 11/30/09 <0.0005 <0.0005 <0.0005 <0.0005 <0.001 <0.0005 -- <0.050 0.29 -- 99.02 12.38 0.00 86.64
MW-2 06/03/10 <0.0005 <0.0005 <0.0005 <0.0005 <0.001 <0.0005 -- <0.022 -- 0.15 99.02 11.07 0.00 87.95
71887 Tables 1SA25 2025_V0 2/14
Table 1
Current and Historical Groundwater Gauging and Analytical Results
Former Chevron Station No. 7-1887
2003 S. Washington Boulevard, Ogden, Utah
Sample Location Date Benzene Toluene Ethyl-Benzene Total Xylenes Naphthalene MTBE Total TPH TPH-GRO
TPH-DRO
w/o SGC
TPH-DRO
w/SGC TOC DTW
Product
Thickness GWE Notes
MM/DD/YY (mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(feet)1 (feet btoc)(feet)(feet)
0.005 1.0 0.7 10 0.700 0.200 -- 1 1 1
0.300 3.0 4 10 0.700 0.200 -- 10 10 10
DERR ISL
RBCA Tier 1 SL Not Applicable
MW-2 03/14/11 <0.0005 <0.0005 <0.0005 <0.0005 <0.001 <0.0005 -- <0.022 -- <0.050 99.02 10.08 0.00 88.94
MW-2 09/14/11 <0.0005 <0.0005 <0.0005 <0.0005 <0.001 <0.0005 -- <0.022 -- <0.050 99.02 10.74 0.00 88.28
MW-2 03/14/12 <0.0005 <0.0005 <0.0005 <0.0005 <0.001 <0.0005 -- <0.022 -- <0.050 98.68 13.13 0.00 85.55 Surveyed 11/11
MW-2 09/11/12 <0.0005 <0.0005 <0.0005 <0.0005 <0.001 <0.0005 -- 0.044 -- <0.050 98.68 13.46 0.00 85.22
MW-2 03/12/13 <0.0005 <0.0005 0.001 0.0006 <0.001 <0.0005 -- 0.710 -- 0.067 98.68 14.27 0.00 84.41
MW-2 09/19/13 <0.0005 <0.0005 <0.0005 <0.0005 <0.001 <0.0005 -- 0.063 -- <0.050 98.68 12.15 0.00 86.53
MW-2 04/07/14 <0.0005 <0.0005 <0.0005 <0.0005 <0.001 <0.0005 -- <0.022 -- <0.050 98.68 12.30 0.00 86.38
MW-2 07/21/14 <0.0005 <0.0005 <0.0005 <0.0005 <0.001 <0.0005 -- <0.022 -- <0.050 98.68 11.44 0.00 87.24
MW-2 09/09/15 <0.0005 <0.0005 <0.0005 <0.0005 <0.001 <0.0005 -- <0.022 -- <0.045 98.68 11.50 0.00 87.18
MW-2 05/01/17 <0.0005 <0.0005 <0.0005 <0.0005 <0.001 <0.0005 -- <0.022 -- <0.045 98.68 9.75 0.00 88.93
MW-2 09/06/17 <0.0005 <0.0005 <0.0005 <0.0005 <0.001 <0.0005 -- <0.022 -- <0.046 98.68 11.36 0.00 87.32
MW-2 12/12/19 <0.0002 <0.0002 <0.0004 <0.001 <0.001 <0.0002 -- <0.025 -- <0.045 98.68 11.43 0.00 87.25
MW-2 04/06/21 98.68 12.35 0.00 86.33
MW-2 09/13/21 <0.0000941 <0.000278 <0.000137 <0.000174 <0.001 <0.000101 --0.0816 J <0.0314 --98.68 11.70 0.00 86.98
MW-2 03/31/22 <0.0000941 <0.000278 <0.000137 <0.000174 <0.001 <0.000101 --<0.0314 0.0747 J --98.68 11.55 0.00 87.13
MW-2 06/08/22 98.68 11.41 0.00 87.27
MW-2 08/10/22 <0.0000941 <0.000278 <0.000137 <0.000174 0.00101 B J <0.000101 --<0.0314 <0.0247 --98.68 11.76 0.04*86.92
MW- 2 DUPLICATE 08/10/22 <0.000941 <00278 <0.00137 <0.00174 <0.010 <0.00101 --<0.0314 <0.0247 --98.68 11.76 0.04*86.92
MW-2 05/16/23 <0.0000941 <0.000278 <0.000137 <0.000174 <0.00100 <0.000101 --<0.0314 <0.0247 <0.0247 98.68 9.15 0.00 89.53
MW- 2 DUPLICATE 05/16/23 <0.0000941 <0.000278 <0.000137 <0.000174 <0.00100 <0.000101 --<0.0314 <0.0247 <0.0247 98.68 9.15 0.00 89.53
MW-2 08/08/23 <0.0000941 <0.000278 <0.000137 <0.000174 <0.00100 <0.000101 --<0.0314 0.0694 B J 0.0694 B J 98.68 10.96 0.00 87.72
MW- 2 DUPLICATE 08/08/23 <0.0000941 <0.000278 <0.000137 <0.000174 <0.00100 <0.000101 --<0.0314 0.0670 B J 0.0684 B J 98.68 10.96 0.00 87.72
MW-2 04/15/24 <0.0000941 <0.000278 <0.000137 <0.000174 <0.00100 <0.000101 --0.0458 B J 0.0327 J <0.0247 98.68 9.22 0.00 89.46
MW-2 09/03/24 <0.0000941 <0.000278 <0.000137 <0.000174 <0.00100 C3 <0.000101 --0.0477 B J 0.0633 J 0.0633 J 98.68 11.24 0.00 87.44
MW-3 03/02/89 1 1.4 0.22 1.3 ----5.6 ------98.96 8.49 0.00 90.47
MW-3 03/02/89 1 1.4 0.22 1.3 ----5.6 ------98.96 8.49 0.00 90.47
MW-3 01/26/90 0.13 0.048 0.016 0.10 ----3.4 ------98.96 9.62 0.00 89.34
MW-3 11/29/90 ND ND ND ND ----ND ------98.96 ------
MW-3 04/23/91 0.0033 ND ND ND ----ND ------98.96 9.71 0.00 89.25
MW-3 07/11/91 ND ND ND ND ----0.581 ------98.96 8.83 0.00 90.13
MW-3 10/01/91 ND ND ND ND ----ND ------98.93 9.68 0.00 89.25 Surveyed 10/91
MW-3 01/01/92 0.0586 ND ND 0.0094 ----ND ------98.93 ------
MW-3 04/01/92 ND ND ND ND ----ND ------98.93 9.22 0.00 89.71
MW-3 07/01/92 0.065 0.0108 0.0098 0.0204 ----ND ------98.93 9.30 0.00 89.63
MW-3 10/01/92 0.0881 0.0094 0.142 0.0267 ----0.263 ------98.93 9.65 0.00 89.28
MW-3 04/26/93 0.088 0.003 0.004 0.006 ----0.390 ------98.93 8.44 0.00 90.49
MW-3 07/20/93 0.51 0.01 0.006 0.018 ----1.1 ------98.93 8.80 0.00 90.13
MW-3 10/27/93 0.57 0.066 0.031 0.069 ----2.5 ------98.93 9.27 0.00 89.66
MW-3 01/26/94 0.042 0.004 0.013 0.009 ----0.42 ------98.93 9.42 0.00 89.51
MW-3 04/29/94 0.07 0.0027 0.0006 0.0067 ----0.40 ------98.93 8.39 0.00 90.54
MW-3 07/28/94 0.18 0.024 0.03 0.021 ----0.98 ------98.93 9.49 0.00 89.44
MW-3 10/11/94 0.22 0.024 0.024 0.025 ----1.5 ------98.93 9.48 0.00 89.45
MW-3 01/20/95 0.002 0.0008 0.0007 0.0012 ----0.092 ------98.93 8.53 0.00 90.40
MW-3 04/21/95 0.0016 0.0006 ND ND ----ND ------98.93 8.21 0.00 90.72
MW-3 07/28/95 0.11 0.0019 0.0025 0.0056 ----0.37 ------98.93 9.11 0.00 89.82
MW-3 07/02/96 0.023 ND ND ND ----0.14 ------98.93 9.02 0.00 89.91
MW-3 08/11/97 0.016 ND ND 0.012 ND ND ND ------98.93 8.50 0.00 90.43
MW-3 08/31/98 0.0082 0.0026 0.0013 0.0038 ND 0.013 0.10 ------98.93 8.62 0.00 90.31
MW-3 04/21/99 0.16 0.34 0.034 0.13 ND ND 1.2 ------98.93 8.35 0.00 90.58
MW-3 08/12/99 0.0231 0.012 0.0101 0.031 <0.350 <0.020 <0.500 ------98.93 8.61 0.00 90.32
MW-3 11/10/99 --------------------98.93 8.92 0.00 90.01
MW-3 03/07/00 0.0129 0.00433 0.00525 0.00846 <0.035 <0.0025 0.456 ------98.93 8.58 0.00 90.35
MW-3 05/17/00 --------------------98.93 9.10 0.00 89.83
ONLY NATURAL ATTENUATION SAMPLES
ONLY NATURAL ATTENUATION SAMPLES
71887 Tables 1SA25 2025_V0 3/14
Table 1
Current and Historical Groundwater Gauging and Analytical Results
Former Chevron Station No. 7-1887
2003 S. Washington Boulevard, Ogden, Utah
Sample Location Date Benzene Toluene Ethyl-Benzene Total Xylenes Naphthalene MTBE Total TPH TPH-GRO
TPH-DRO
w/o SGC
TPH-DRO
w/SGC TOC DTW
Product
Thickness GWE Notes
MM/DD/YY (mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(feet)1 (feet btoc)(feet)(feet)
0.005 1.0 0.7 10 0.700 0.200 -- 1 1 1
0.300 3.0 4 10 0.700 0.200 -- 10 10 10
DERR ISL
RBCA Tier 1 SL Not Applicable
MW-3 08/10/00 --------------------98.93 9.13 0.00 89.80
MW-3 11/08/00 --------------------98.93 9.64 0.00 89.29
MW-3 02/06/01 0.0181 0.0027 0.0072 0.0197 0.0098 <0.002 0.620 ------98.93 9.93 0.00 89.00
MW-3 05/01/01 --------------------98.93 9.39 0.00 89.54
MW-3 08/22/01 --------------------98.93 9.24 0.00 89.69
MW-3 11/15/01 --------------------98.93 10.01 0.00 88.92
MW-3 02/25/02 --------------------98.93 9.75 0.00 89.18
MW-3 05/21/02 --------------------98.93 8.74 0.00 90.19
MW-3 08/20/02 --------------------98.93 9.10 0.00 89.83
MW-3 11/05/02 --------------------98.93 9.48 0.00 89.45
MW-3 03/19/03 0.0086 0.0031 0.0065 0.018 0.011 <0.0025 0.83 ------98.93 9.37 0.00 89.56
MW-3 06/17/03 --------------------98.93 8.92 0.00 90.01
MW-3 09/30/03 --------------------98.93 9.29 0.00 89.64
MW-3 11/25/03 --------------------98.93 9.40 0.00 89.53
MW-3 12/13/07 0.002 0.0006 0.002 0.002 0.004 <0.0005 --1.1 --1.1 98.93 10.09 0.00 88.84
MW-3 06/03/08 <0.0005 <0.0005 <0.0005 <0.0005 0.006 <0.0005 --0.76 0.64 --98.93 10.12 0.00 88.81
MW-3 12/01/08 <0.0005 <0.0005 <0.0005 <0.0005 <0.001 <0.0005 --0.32 1.5 --98.93 11.45 0.00 87.48
MW-3 06/01/09 <0.0005 <0.0005 <0.0005 <0.0005 <0.001 <0.0005 --0.13 0.47 --98.93 10.85 0.00 88.08
MW-3 11/30/09 <0.0005 <0.0005 <0.0005 <0.0005 <0.001 <0.0005 --0.088 1.1 --98.93 12.16 0.00 86.77
MW-3 06/03/10 <0.0005 <0.0005 <0.0005 <0.0005 <0.001 <0.0005 --0.13 --0.74 98.93 10.79 0.00 88.14
MW-3 03/14/11 0.0006 <0.0005 0.0008 <0.0005 0.002 <0.0005 --0.22 --0.56 98.93 9.95 0.00 88.98
MW-3 09/14/11 <0.0005 <0.0005 <0.0005 0.0009 0.003 <0.0005 --0.19 --0.12 98.93 10.55 0.00 88.38
MW-3 03/14/12 <0.0005 <0.0005 <0.0005 <0.0005 <0.001 <0.0005 --0.065 --0.069 98.66 12.90 0.00 85.76 Surveyed 11/11
MW-3 09/11/12 0.001 <0.0005 0.001 0.001 <0.001 <0.0005 --0.17 --0.063 98.66 14.23 0.00 84.43
MW-3 03/12/13 <0.0005 <0.0005 <0.0005 <0.0005 <0.001 <0.0005 --0.18 --0.17 98.66 13.93 0.00 84.73
MW-3 09/19/13 0.0006 <0.0005 0.0008 <0.0005 0.002 <0.0005 --0.22 --0.15 98.66 11.95 0.00 86.71
MW-3 04/07/14 <0.0005 <0.0005 <0.0005 <0.0005 <0.001 <0.0005 --0.065 --0.071 98.66 12.16 0.00 86.50
MW-3 07/21/14 0.002 <0.0005 0.002 0.0006 0.006 <0.0005 --0.43 --0.090 98.66 11.22 0.00 87.44
MW-3 09/09/15 <0.0005 <0.0005 <0.0005 <0.0005 0.004 <0.0005 --0.19 --0.11 98.66 11.25 0.00 87.41
MW-3 01/10/17 <0.0005 <0.0005 <0.0005 <0.0005 0.003 <0.0005 --0.13 --<0.046 98.66 11.86 0.00 86.80
MW-3 05/01/17 0.001 <0.0005 0.0007 0.0006 0.01 <0.0005 --0.26 --0.046 98.66 9.48 0.00 89.18
MW-3 09/06/17 0.001 <0.0005 <0.0005 <0.0005 0.008 <0.0005 --0.35 --0.047 98.66 11.13 0.00 87.53
MW-3 12/12/19 <0.0002 <0.0002 <0.0004 <0.001 <0.001 <0.0002 --0.045 J --<0.046 98.66 11.27 0.00 87.39
MW-3 04/06/21 98.66 12.85 0.00 85.81
MW-3 09/13/21 0.000151 J <0.000278 <0.000137 <0.000174 <0.001 <0.000101 --0.121 0.253 --98.66 11.54 0.00 87.12
MW-3 03/31/22 0.000144 J <0.000278 <0.000137 <0.000174 <0.001 <0.000101 --0.188 B 0.401 --98.66 11.41 0.00 87.25
MW-3 06/09/22 98.66 11.21 0.00 87.45
MW-3 08/10/22 0.000345 J <0.000278 <0.000137 <0.000174 0.00140 B J <0.000101 --0.197 B 0.15 --98.66 11.54 0.01*87.12
MW-3 05/16/23 0.000332 J <0.000278 <0.000137 <0.000174 <0.00100 <0.000101 --0.0356 J 0.588 <0.0247 98.66 8.89 0.00 89.77
MW-3 08/08/23 0.000167 J <0.000278 <0.000137 <0.000174 <0.00100 <0.000101 --0.1040 0.678 0.102 B 98.66 10.88 0.00 87.78
MW-3 04/15/24 0.000132 J <0.000278 <0.000137 <0.000174 <0.00100 <0.000101 --0.0720 B J 0.771 <0.0247 98.66 8.92 0.00 89.74
MW-3 09/03/24 <0.0000941 <0.000278 <0.000137 <0.000174 <0.00100 C3 <0.000101 -- 0.0890 B J 0.384 0.106 B 98.66 11.08 0.00 87.58
MW-4 04/23/91 0.4 0.229 0.0245 7.66 ----------99.17 10.25 0.00 88.92
MW-4 01/20/93 --------------------98.94 9.57 0.50 89.75 Surveyed 10/91
MW-4 04/19/93 --------------------98.94 8.82 0.60 90.57
MW-4 07/20/93 0.23 0.019 0.039 0.049 ----0.720 ------98.94 9.30 0.48 90.00
MW-4 10/27/93 --------------------98.94 10.04 0.63 89.37
MW-4 01/26/94 --------------------98.94 9.60 0.24 89.52
MW-4 04/29/94 --------------------98.94 8.45 0.03 90.51
MW-4 01/20/95 --------------------98.94 8.77 0.01 90.18
MW-4 07/02/96 0.47 0.084 0.06 0.8 ----8.9 ------98.94 9.32 0.00 89.62
MW-4 08/11/97 0.96 0.080 ND 0.34 ND ND 9.0 ------98.94 8.80 0.00 90.14
MW-4 08/31/98 1.5 0.013 ND 0.054 ND 0.230 4.5 ------98.94 8.87 0.00 90.07
ONLY NATURAL ATTENUATION SAMPLES
ONLY NATURAL ATTENUATION SAMPLES
71887 Tables 1SA25 2025_V0 4/14
Table 1
Current and Historical Groundwater Gauging and Analytical Results
Former Chevron Station No. 7-1887
2003 S. Washington Boulevard, Ogden, Utah
Sample Location Date Benzene Toluene Ethyl-Benzene Total Xylenes Naphthalene MTBE Total TPH TPH-GRO
TPH-DRO
w/o SGC
TPH-DRO
w/SGC TOC DTW
Product
Thickness GWE Notes
MM/DD/YY (mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(feet)1 (feet btoc)(feet)(feet)
0.005 1.0 0.7 10 0.700 0.200 -- 1 1 1
0.300 3.0 4 10 0.700 0.200 -- 10 10 10
DERR ISL
RBCA Tier 1 SL Not Applicable
MW-4 04/21/99 0.96 0.016 0.014 0.06 ND ND 2.0 ------98.94 8.60 0.00 90.34
MW-4 08/12/99 0.981 0.0644 0.0184 0.0969 0.383 <0.020 14.0 ------98.94 8.86 0.00 90.08
MW-4 11/10/99 1.21 <0.050 <0.050 0.104 <3.500 <0.200 12.9 ------98.94 9.10 0.00 89.84
MW-4 03/07/00 0.901 0.0141 <0.010 <0.010 <0.700 <0.050 3.26 ------98.94 8.76 0.00 90.18
MW-4 05/17/00 0.634 0.0177 0.016 0.109 0.118 <0.002 4.2 ------98.94 9.20 0.00 89.74
MW-4 08/10/00 0.822 0.0209 <0.020 0.128 0.115 <0.020 3.5 ------98.94 9.35 0.00 89.59
MW-4 11/08/00 --------------------98.94 9.75 0.03 89.21
MW-4 02/06/01 --------------------98.94 10.06 0.06 88.93
MW-4 05/01/01 0.751 0.0268 0.0193 0.0989 0.0468 <0.100 2.4 ------98.94 9.56 0.00 89.38
MW-4 08/22/01 1.5 0.029 0.026 0.14 0.120 <0.002 4.8 ------98.94 9.43 0.00 89.51
MW-4 11/15/01 --------------------98.94 10.15 0.05 88.83
MW-4 02/25/02 --------------------98.94 9.84 0.04 89.13
MW-4 05/21/02 0.67 0.018 0.015 0.087 0.110 <0.020 5.5 ------98.94 8.91 0.00 90.03
MW-4 08/20/02 0.60 0.021 0.017 0.11 0.130 <0.025 4.0 ------98.94 9.22 0.00 89.72
MW-4 11/05/02 0.59 0.022 0.018 0.12 0.120 <0.050 4.2 ------98.94 9.57 0.00 89.37
MW-4 03/19/03 0.16 0.0077 0.009 0.055 0.060 <0.013 3.1 ------98.94 9.35 0.00 89.59
MW-4 06/17/03 0.15 0.005 0.005 0.030 0.037 ND 1.5 ------98.94 9.06 0.00 89.88
MW-4 09/30/03 0.17 0.009 0.008 0.046 0.045 <0.0005 2.3 ------98.94 9.37 0.00 89.57
MW-4 11/25/03 0.017 0.002 0.002 0.010 0.010 <0.0005 0.990 ------98.94 9.46 0.00 89.48
MW-4 12/13/07 0.0006 <0.0005 <0.0005 <0.0005 0.002 <0.0005 --0.280 --30 98.94 10.13 0.00 88.81
MW-4 06/03/08 0.005 0.0009 <0.0005 0.001 0.003 <0.0005 --0.500 19 --98.94 10.42 0.00 88.52
MW-4 12/01/08 0.072 0.004 0.001 0.005 0.002 <0.0005 --2.0 49 --98.94 11.60 0.00 87.34
MW-4 06/01/09 0.021 0.002 0.0007 0.003 0.002 <0.0005 --1.7 66 --98.94 11.31 0.00 87.63
MW-4 11/30/09 0.005 0.0008 <0.0005 0.002 0.001 <0.0005 --1.8 14 --98.94 12.34 0.00 86.60
MW-4 06/03/10 0.004 <0.0005 <0.0005 0.002 <0.001 <0.0005 --0.500 --26 98.94 11.11 0.00 87.83
MW-4 03/14/11 <0.0005 0.0006 <0.0005 <0.0005 <0.001 <0.0005 --0.440 --12 98.94 10.28 0.00 88.66
MW-4 09/14/11 0.024 0.004 0.002 0.007 0.002 <0.0005 --0.780 --6.7 98.94 10.50 0.00 88.44
MW-4 03/14/12 0.054 0.003 0.001 0.006 0.001 <0.0005 --3.6 ----98.20 12.91 0.00 85.29 Surveyed 11/11
MW-4 09/11/12 0.068 0.006 0.003 0.014 0.003 <0.0005 --2.2 --6.3 98.20 13.18 0.00 85.02
MW-4 03/12/13 0.077 0.005 0.004 0.019 0.003 <0.0005 --2.8 --35 98.20 13.91 0.00 84.29
MW-4 06/03/13 0.098 0.006 0.005 0.024 0.004 <0.0005 --2.8 --10 98.20 13.08 0.00 85.12
MW-4 07/09/13
MW-4 07/09/13 0.009 0.0007 <0.022 0.001 <0.001 <0.0005 --0.440 --9.3 98.20 13.25 0.00 84.95
MW-4 08/14/13 0.026 0.001 <0.0005 0.005 <0.001 <0.0005 --1.2 --2.1 98.20 11.98 0.00 86.22
MW-4 09/19/13 0.055 0.003 0.001 0.01 0.002 <0.0005 --2.0 --1.4 98.20 11.86 0.00 86.34
MW-4 04/07/14 0.057 0.002 0.001 0.009 0.002 <0.0005 --1.4 --1.6 98.20 11.95 0.00 86.25
MW-4 07/21/14 0.063 0.002 0.002 0.011 0.003 <0.0005 --1.9 --7.4 98.20 11.19 0.00 87.01
MW-4 09/09/15 0.045 0.002 0.002 0.011 0.002 <0.0005 --1.9 --5.4 98.20 11.25 0.00 86.95
MW-4 01/10/17 0.027 0.002 0.002 0.011 0.003 <0.0005 --1.3 --5.6 98.20 11.72 0.00 86.48
MW-4 05/01/17 0.004 0.001 0.002 0.006 0.015 <0.0005 --1.5 --3.4 98.20 9.63 0.00 88.57
MW-4 09/06/17 0.012 0.001 0.0007 0.004 0.001 <0.0005 --1.0 --1.6 98.20 11.10 0.00 87.10
MW-4 12/12/19 0.007 J*0.0009 J <0.0004 0.005 J 0.003 J <0.0002 --0.910 --1.2 98.20 11.15 0.00 87.05
MW-4 04/06/21 98.20 12.08 0.00 86.12
MW-4 09/13/21 0.00761 0.00179 0.000787 J 0.00705 0.00185 J <0.000101 --8.35 1.38 --98.20 11.40 0.00 86.80
MW-4 03/31/22 0.00432 0.000305 J <0.000137 0.00126 J <0.001 <0.000101 --1.11 12.2 --98.20 11.29 0.00 86.91
MW-4 06/08/22 98.20 11.08 0.00 87.12
MW-4 08/10/22 0.016 0.00168 0.000464 J 0.00369 0.00170 B J <0.000101 --2.11 24.1 --98.20 11.39 0.01*86.81
MW-4 05/16/23 0.00127 0.000280 J <0.000137 0.000786 J <0.00100 <0.000101 --0.601 0.415 <0.0247 98.20 8.96 0.00 89.24
MW-4 08/09/23 0.00450 0.000835 J 0.000948 J 0.004420 0.010 <0.000101 --0.931 2.010 0.43 98.20 10.00 0.00 88.20
MW-4 04/16/24 0.000920 J 0.000307 J 0.000201 J 0.00134 J 0.00127 J <0.000101 --0.776 0.995 <0.0247 98.20 9.00 0.00 89.20
MW-4 09/04/24 0.00411 0.00158 0.000665 J 0.00368 0.00111 J <0.000101 -- 0.798 B 2.76 0.315 B 98.20 10.94 0.00 87.26
MW-5 03/02/89 1.1 1.6 0.25 1.5 ----6.6 ------100.03 ------
MW-5 06/21/89 2.2 0.24 0.42 2.0 ----20 ------100.03 10.76 0.00 89.27
ONLY NATURAL ATTENUATION SAMPLES
ONLY NATURAL ATTENUATION SAMPLES
HYDROGEN PEROXIDE AMENDMENT ADDED DIRECTLY TO WELL IN JUNE AND JULY 2013
71887 Tables 1SA25 2025_V0 5/14
Table 1
Current and Historical Groundwater Gauging and Analytical Results
Former Chevron Station No. 7-1887
2003 S. Washington Boulevard, Ogden, Utah
Sample Location Date Benzene Toluene Ethyl-Benzene Total Xylenes Naphthalene MTBE Total TPH TPH-GRO
TPH-DRO
w/o SGC
TPH-DRO
w/SGC TOC DTW
Product
Thickness GWE Notes
MM/DD/YY (mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(feet)1 (feet btoc)(feet)(feet)
0.005 1.0 0.7 10 0.700 0.200 -- 1 1 1
0.300 3.0 4 10 0.700 0.200 -- 10 10 10
DERR ISL
RBCA Tier 1 SL Not Applicable
MW-5 04/23/91 0.555 0.304 0.179 7.83 ----1,670 ------100.03 11.40 0.00 88.63
MW-5 04/19/93 --------------------99.95 9.79 0.00 90.16 Surveyed 10/91
MW-5 07/20/93 --------------------99.95 10.10 0.00 89.85
MW-5 10/27/93 --------------------99.95 10.52 0.00 89.43
MW-5 01/26/94 --------------------99.95 10.72 0.00 89.23
MW-5 04/29/94 --------------------99.95 9.72 0.00 90.23
MW-5 07/28/94 --------------------99.95 10.60 0.00 89.35
MW-5 10/11/94 0.32 0.019 0.014 0.063 ----2.9 ------99.95 10.65 0.00 89.30
MW-5 01/20/95 0.35 0.014 0.017 0.054 ----1.5 ------99.95 9.75 0.00 90.20
MW-5 04/21/95 --------------------99.95 ----99.95
MW-5 07/25/95
MW-6 06/21/89 7.9 8.3 1.3 9.3 ----60 ------99.83 10.53 0.00 89.30
MW-6 01/26/90 6.7 5.0 0.840 4.6 ----34 ------99.83 10.74 0.00 89.09
MW-6 11/29/90 3.53 4.66 0.360 5.91 ----25.5 ------99.83 ------
MW-6 04/23/91 0.371 0.0482 0.0074 2.18 ----23.8 ------99.83 10.68 0.00 89.15
MW-6 07/11/91 0.605 0.62 14.3 1.54 ----13.3 ------99.83 9.42 0.00 90.41
MW-6 04/01/92 3.38 1.5 0.37 4.22 ----454 ------99.71 10.15 0.00 89.56 Surveyed 10/91
MW-6 07/01/92 2.78 1.42 0.453 4.11 ----25.5 ------99.71 9.86 0.00 89.85
MW-6 01/20/93 --------------------99.71 10.61 0.50 89.48
MW-6 04/19/93 --------------------99.71 9.13 0.40 90.88
MW-6 07/20/93 --------------------99.71 9.55 0.20 90.31
MW-6 10/27/93 --------------------99.71 9.25 0.28 90.67
MW-6 04/29/94 --------------------99.71 7.48 0.02 92.25
MW-6 01/20/95 --------------------99.71 9.90 0.01 89.82
MW-6 07/02/96 0.160 0.030 0.012 2.1 ----11 ------99.71 10.63 0.00 89.08
MW-6 08/11/97 0.770 ND ND 0.500 ND ND 1.3 ------99.71 9.85 0.00 89.86
MW-6 08/31/98 0.390 ND ND 0.026 ND 0.16 2.2 ------99.71 9.70 0.00 90.01
MW-6 11/10/99 0.392 0.102 0.0461 0.514 <0.350 <0.020 3.36 ------99.71 9.81 0.00 89.90
MW-6 03/07/00 1.06 0.0928 0.0486 0.274 <0.350 <0.025 4.08 ------99.71 9.50 0.00 90.21
MW-6 05/17/00 0.858 0.171 0.0125 0.941 0.0704 <0.020 7.3 ------99.71 9.96 0.00 89.75
MW-6 08/10/00 0.789 0.143 0.132 1.11 0.0893 <0.010 8.3 ------99.71 10.10 0.00 89.61
MW-6 11/08/00 0.735 0.0985 0.112 0.845 0.0863 <0.010 1.8 ------99.71 10.53 0.00 89.18
MW-6 02/06/01 0.851 0.0829 0.0745 0.490 0.0396 <0.010 5.8 ------99.71 10.69 0.00 89.02
MW-6 05/01/01 0.988 0.128 0.154 0.904 <0.100 <0.100 9.5 ------99.71 10.27 0.00 89.44
MW-6 08/22/01 0.760 0.098 0.11 0.430 0.08 <0.002 4.1 ------99.71 10.04 0.00 89.67
MW-6 11/15/01 0.630 0.069 0.09 0.500 0.056 <0.100 4.8 ------99.71 10.93 0.00 88.78
MW-6 02/25/02 0.990 0.067 0.096 0.440 0.062 <0.025 6.4 ------99.71 10.55 0.00 89.16
MW-6 05/21/02 1.40 0.094 0.17 0.710 0.085 0.045 9.1 ------99.71 9.77 0.00 89.94
MW-6 08/20/02 0.790 0.120 0.15 0.710 0.11 0.031 6.9 ------99.71 10.04 0.00 89.67
MW-6 11/05/02 0.630 0.068 0.093 0.390 0.068 <0.013 5.1 ------99.71 10.42 0.00 89.29
MW-6 03/19/03 2.0 0.099 0.12 0.320 0.058 <0.025 7.4 ------99.71 10.32 0.00 89.39
MW-6 06/17/03 1.2 0.120 0.18 0.540 0.088 ND 7.1 ------99.71 9.92 0.00 89.79
MW-6 09/30/03 1.4 0.051 0.2 0.360 0.097 <0.001 6.7 ------99.71 10.23 0.00 89.48
MW-6 11/25/03 1.0 0.022 0.12 0.160 0.055 <0.0005 4.8 ------99.71 10.33 0.00 89.38
MW-6 12/13/07 0.770 0.041 0.015 0.093 0.012 <0.001 --3.6 --14 99.71 10.95 0.00 88.76
MW-6 06/03/08 0.750 0.044 0.011 0.073 0.009 <0.0005 --3.7 42 --99.71 11.26 0.00 88.45
MW-6 12/01/08 DRY DRY 99.71 12.41 0.00 87.30
MW-6 06/01/09 DRY DRY 99.71 ------
MW-6 06/03/10 DRY DRY 99.71 ------
MW-6 03/14/11 1.7 0.033 0.048 0.170 0.031 <0.003 --8.5 --18 99.71 11.11 0.00 88.60
MW-6 09/14/11 1.5 0.300 0.7 2.3 0.16 <0.0005 --31 --6.3 99.71 12.00 0.00 87.71
MW-6 03/14/12 0.410 0.078 0.21 0.650 0.07 <0.003 --13 --5.3 99.75 14.50 0.00 85.25 Surveyed 11/11
MW-6 09/11/12 3.2 0.790 0.71 2.1 0.15 <0.005 --20 --1.8 99.75 14.75 0.00 85.00
MW-6 03/12/13 1.4 0.170 0.19 0.710 0.048 <0.0005 --11 --3.5 99.75 15.50 0.00 84.25
WELL WAS DESTROYED
DRY
DRY
INSUFFICIENT WATER TO SAMPLE
71887 Tables 1SA25 2025_V0 6/14
Table 1
Current and Historical Groundwater Gauging and Analytical Results
Former Chevron Station No. 7-1887
2003 S. Washington Boulevard, Ogden, Utah
Sample Location Date Benzene Toluene Ethyl-Benzene Total Xylenes Naphthalene MTBE Total TPH TPH-GRO
TPH-DRO
w/o SGC
TPH-DRO
w/SGC TOC DTW
Product
Thickness GWE Notes
MM/DD/YY (mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(feet)1 (feet btoc)(feet)(feet)
0.005 1.0 0.7 10 0.700 0.200 -- 1 1 1
0.300 3.0 4 10 0.700 0.200 -- 10 10 10
DERR ISL
RBCA Tier 1 SL Not Applicable
MW-6 06/03/13 3.2 0.350 0.43 1.2 0.077 <0.003 --15 --3.3 99.75 14.23 0.00 85.52
MW-6 --
MW-6 07/09/13 0.008 <0.0005 <0.0005 0.0009 <0.001 <0.0005 --0.170 --1.2 99.75 14.80 0.00 84.95
MW-6 08/14/13 0.015 0.001 0.0008 0.004 <0.001 <0.0005 --0.300 --0.810 99.75 13.58 0.00 86.17
MW-6 09/19/13 0.820 0.014 0.061 0.075 0.02 <0.0005 --2.6 --0.860 99.75 13.41 0.00 86.34
MW-6 04/07/14 1.2 0.027 0.076 0.055 0.014 <0.0005 --3.7 --0.920 99.75 13.53 0.00 86.22
MW-6 --
MW-6 07/21/14 1.9 0.039 0.061 0.084 0.02 <0.003 --4.0 --1.9 99.75 12.78 0.00 86.97
MW-6 09/09/15 1.7 0.074 0.095 0.140 0.03 <0.0005 --5.9 --3.1 99.75 12.75 0.00 87.00
MW-6 01/10/17 0.810 0.006 0.008 0.014 0.007 <0.0005 --2.3 --0.150 99.75 13.28 0.00 86.47
MW-6 05/01/17 1.3 0.009 0.031 0.023 0.013 <0.003 --3.1 --0.240 99.75 11.18 0.00 88.57
MW-6 09/06/17 2.4 0.022 0.2 0.026 0.034 <0.010 --6.9 --0.140 99.75 12.66 0.00 87.09
MW-6 12/12/19 1.2 J*0.017 0.015 0.020 J 0.018 J <0.002 --3.4 --0.110 J 99.75 12.71 0.00 87.04
MW-6 DUPLICATE 12/12/19 1.2 J*0.016 0.016 0.016 J 0.017 J <0.002 --3.2 --0.110 99.75 12.71 0.00 87.04
MW-6 04/06/21 99.75 13.56 0.00 86.19
MW-6 06/17/21
MW-6 09/13/21 0.168 0.00185 0.00164 0.00381 0.00148 J <0.000101 --0.802 0.807 --99.75 12.95 0.00 86.80
MW-6 DUPLICATE 09/13/21 0.167 0.00165 0.00159 0.00371 0.0016 J <0.000101 --0.780 0.838 --99.75 12.95 0.00 86.80
MW-6 12/28/21 0.0641 0.000774 J 0.000247 J 0.00145 J <0.001 <0.000101 --0.315 0.246 --99.75 13.45 0.00 86.30
MW-6 DUPLICATE 12/28/21 0.0640 0.000794 J 0.000242 J 0.0015 J <0.001 <0.000101 --0.359 0.270 --99.75 13.45 0.00 86.30
MW-6 03/31/22 0.0365 0.000574 J <0.000137 0.000847 J <0.001 <0.000101 --0.163 B 0.241 --99.75 13.31 0.00 86.44
MW-6 06/08/22 0.0411 0.000403 J 0.000144 J 0.000829 J <0.001 <0.000101 --0.300 0.196 --99.75 12.65 0.00 87.10
MW-6 08/10/22 0.0176 <0.00278 <0.00137 <0.00174 <0.010 <0.00101 --0.0964 B J 0.336 --99.75 12.96 0.01*86.79
MW-6 05/16/23 0.184 0.0213 <0.000137 0.0639 <0.00100 <0.000101 -- 0.101 0.0992 J 0.0990 J 99.75 10.55 0.00 89.20
MW-6 08/09/23 0.185 <0.00278 <0.00137 <0.00174 <0.0100 <0.00101 -- 0.699 0.645 0.232 B 99.75 12.25 0.00 87.50
MW-6 04/16/24 0.0388 0.000417 J 0.000143 J 0.000638 J <0.00100 <0.000101 -- 0.170 B 0.223 B <0.0247 99.75 10.59 0.00 89.16
MW-6 DUPLICATE 04/16/24 0.0273 <0.000278 <0.000137 <0.000174 <0.00100 <0.000101 -- 0.142 B 0.216 B <0.0247 99.75 10.59 0.00 89.16
MW-6 09/04/24 0.184 0.00217 0.000437 J 0.00359 0.00179 J <0.000101 --1.09 0.601 0.388 B 99.75 12.48 0.00 87.27
MW-6 DUPLICATE 09/04/24 0.170 0.00197 0.000375 J 0.00331 0.00153 J <0.000101 --1.01 0.589 0.378 B 99.75 12.48 0.00 87.27
MW-7 06/21/89 0.9 0.1 0.07 0.57 ----4.3 ------98.08 8.85 0.00 89.23
MW-7 01/26/90 2.1 0.068 0.015 0.19 ----3.9 ------98.08 9.03 0.00 89.05
MW-7 11/29/90 1.3 ND ND ND ----1.99 ------98.08 ----98.08
MW-7 04/23/91 ND ND ND 0.0058 ----1.8 ------98.08 9.09 0.00 88.99
MW-7 07/11/91 ND ND ND ND ----1.67 ------98.08 8.31 0.00 89.77
MW-7 10/01/91 ND ND ND 0.0655 ----ND ------98.08 9.12 0.00 88.96
MW-7 01/01/92 0.303 ND ND 0.0137 ----0.300 ------98.08 8.60 0.00 89.48
MW-7 04/01/92 0.0367 ND ND 0.0107 ----0.390 ------98.08 8.65 0.00 89.43
MW-7 07/01/92 0.837 ND ND 0.0845 ----1.48 ------98.08 8.75 0.00 89.33
MW-7 10/01/92 1.06 ND ND 0.053 ----1.84 ------98.08 9.06 0.00 89.02
MW-7 01/21/93 1.3 0.018 0.011 0.053 ----3.1 ------98.08 8.61 0.00 89.47
MW-7 04/25/93 0.89 0.076 0.053 0.15 ----2.0 ------98.08 7.94 0.00 90.14
MW-7 07/20/93 --------------------98.08 8.30 0.00 89.78
MW-7 10/27/93 0.13 0.009 0.003 0.016 ----0.320 ------98.08 8.67 0.00 89.41
MW-7 01/26/94 0.23 0.003 0.0007 0.007 ----0.370 ------98.08 8.84 0.00 89.24
MW-7 04/29/94 0.011 0.0008 ND 0.0023 ----0.070 ------98.08 7.88 0.00 90.20
MW-7 07/28/94 0.065 0.0008 ND 0.0031 ----0.130 ------98.08 8.90 0.00 89.18
MW-7 10/11/94 0.12 0.0016 0.0006 0.0035 ----0.370 ------98.08 8.83 0.00 89.25
MW-7 01/20/95 ND ND ND ND ----ND ------98.08 9.05 0.00 89.03
MW-7 04/21/95 0.0082 0.0007 ND 0.0006 ----0.059 ------98.08 7.73 0.00 90.35
MW-7 07/25/95 0.0038 ND ND ND ----ND ------98.08 8.55 0.00 89.53
MW-7 07/02/96 0.0033 ND ND ND ----ND ------98.08 8.48 0.00 89.60
MW-7 08/31/98 0.330 0.0039 ND 0.020 ND 0.028 0.500 ------98.08 8.07 0.00 90.01
MW-7 04/21/99 0.270 0.0084 ND 0.022 ND ND 0.420 ------98.08 7.84 0.00 90.24
HYDROGEN PEROXIDE AMENDMENT ADDED DIRECTLY TO WELL IN JUNE AND JULY 2013
PERMEABLE FILLED BORINGS WITH SULFATE ADDED UPGRADIENT AND DOWNGRADIENT
ONLY NATURAL ATTENUATION SAMPLES
HYDROGEN PEROXIDE AMENDMENT ADDED DIRECTLY TO WELL IN APRIL AND JULY 2014
71887 Tables 1SA25 2025_V0 7/14
Table 1
Current and Historical Groundwater Gauging and Analytical Results
Former Chevron Station No. 7-1887
2003 S. Washington Boulevard, Ogden, Utah
Sample Location Date Benzene Toluene Ethyl-Benzene Total Xylenes Naphthalene MTBE Total TPH TPH-GRO
TPH-DRO
w/o SGC
TPH-DRO
w/SGC TOC DTW
Product
Thickness GWE Notes
MM/DD/YY (mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(feet)1 (feet btoc)(feet)(feet)
0.005 1.0 0.7 10 0.700 0.200 -- 1 1 1
0.300 3.0 4 10 0.700 0.200 -- 10 10 10
DERR ISL
RBCA Tier 1 SL Not Applicable
MW-7 08/12/99 0.490 0.040 0.015 0.219 <0.070 <0.004 2.0 ------98.08 8.05 0.00 90.03
MW-7 11/10/99 0.619 0.00952 <0.005 0.059 <0.350 <0.020 1.8 ------98.08 8.35 0.00 89.73
MW-7 03/07/00 0.246 0.0598 0.00676 0.0693 <0.035 <0.0025 0.947 ------98.08 7.97 0.00 90.11
MW-7 05/17/00 0.346 0.0133 <0.002 0.0821 0.0082 <0.002 1.4 ------98.08 8.54 0.00 89.54
MW-7 08/10/00 0.730 0.131 0.120 1.01 0.0803 <0.010 7.3 ------98.08 8.59 0.00 89.49
MW-7 11/08/00 0.0122 <0.002 <0.002 <0.006 <0.002 <0.002 <0.500 ------98.08 9.00 0.00 89.08
MW-7 02/06/01 0.238 <0.010 <0.010 <0.030 <0.010 <0.010 0.810 ------98.08 9.26 0.00 88.82
MW-7 05/01/01 0.048 <0.002 <0.002 <0.006 <0.002 <0.002 <0.500 ------98.08 8.78 0.00 89.30
MW-7 12/01/07
MW-8 08/01/89 0.71 4 1.1 8.7 ----51 ------98.4 9.19 0.00 89.21
MW-8 01/26/90 0.8 1.4 0.63 2.4 ----60 ------98.4 9.38 0.00 89.02
MW-8 11/14/90 0.083 0.207 0.449 1.25 ----7.12 ------98.4 9.70 0.00 88.70
MW-8 04/23/91 0.241 0.225 0.648 3.4 ----18.5 ------98.4 9.50 0.00 88.90
MW-8 07/11/91 0.195 0.123 0.319 1.0 ----14.2 ------98.4 8.85 0.00 89.55
MW-8 10/01/91 0.132 0.224 0.33 1.7 ----9.4 ------98.4 9.49 0.00 88.91
MW-8 01/01/92 0.109 0.037 0.312 1.06 ----3.83 ------98.4 9.00 0.00 89.40
MW-8 04/01/92 0.103 0.0104 0.197 0.51 ----4.05 ------98.4 9.06 0.00 89.34
MW-8 07/01/92 0.0532 0.0058 0.163 0.338 ----1.84 ------98.4 9.13 0.00 89.27
MW-8 10/01/92 0.118 ND 0.261 0.587 ----2.87 ------98.4 9.45 0.00 88.95
MW-8 01/21/93 0.24 0.058 0.43 1.0 ----6.4 ------98.4 8.96 0.00 89.44
MW-8 04/26/93 0.057 0.021 0.37 0.91 ----6.7 ------98.4 8.40 0.00 90.00
MW-8 07/20/93 0 0.028 0.33 1.2 ----5.8 ------98.4 8.71 0.00 89.69
MW-8 10/27/93 0.025 0.017 0.13 0.73 ----3.3 ------98.4 9.08 0.00 89.32
MW-8 01/26/94 0.035 0.001 0.013 0.064 ----1.0 ------98.4 9.26 0.00 89.14
MW-8 04/29/94 0.019 0.021 0.34 1.3 ----7.8 ------98.4 8.30 0.00 90.10
MW-8 07/28/94 0.0083 ND 0.0096 0.045 ----0.95 ------98.4 9.28 0.00 89.12
MW-8 04/21/99 --------------------98.4 8.21 0.00 90.19
MW-8 12/01/07
MW-9 08/01/89 0.53 0.067 0.23 0.72 ----4.3 ------96.88 7.80 0.00 89.08
MW-9 01/26/90 0.39 0.052 ND 0.15 ----1.1 ------96.88 7.97 0.00 88.91
MW-9 11/14/90 0.15 ND 0.124 0.146 ----0.840 ------96.88 8.32 0.00 88.56
MW-9 04/23/91 ND ND ND ND ----0.600 ------96.88 8.08 0.00 88.80
MW-9 07/11/91 0.0054 ND ND ND ----1.09 ------96.88 7.46 0.00 89.42
MW-9 10/01/91 0.169 0.0069 0.0363 0.218 ----0.670 ------96.88 8.14 0.00 88.74
MW-9 01/01/92 0.16 0.0117 0.0328 0.108 ----0.330 ------96.88 7.62 0.00 89.26
MW-9 04/01/92 0.0609 ND 0.0036 0.0185 ----ND ------96.88 7.70 0.00 89.18
MW-9 07/01/92 0.107 ND 0.005 0.0045 ----0.290 ------96.88 7.77 0.00 89.11
MW-9 10/01/92 0.147 ND 0.0062 0.0171 ----0.257 ------96.88 8.06 0.00 88.82
MW-9 01/21/93 0.12 0.007 0.04 0.1 ----0.980 ------96.88 7.63 0.00 89.25
MW-9 04/26/93 0.16 0.037 0.044 0.071 ----0.910 ------96.88 7.00 0.00 89.88
MW-9 DUPLICATE 04/26/93 0.14 0.039 0.041 0.07 ----0.780 ------96.88 ----96.88
MW-9 07/20/93 0.002 ND ND 0.003 ----0.170 ------96.88 7.40 0.00 89.48
MW-9 10/27/93 0.1 0.005 0.005 0.01 ----0.630 ------96.88 7.70 0.00 89.18
MW-9 01/26/94 0.072 ND 0.0009 0.001 ----0.510 ------96.88 7.85 0.00 89.03
MW-9 04/29/94 0.05 0.0016 0.002 0.0043 ----0.330 ------96.88 7.02 0.00 89.86
MW-9 07/28/94 0.065 0.0013 ND 0.0019 ----0.380 ------96.88 7.94 0.00 88.94
MW-9 12/01/07
MW-10 08/01/89 0.51 2.4 0.14 2.3 ----12 ------96.67 7.71 0.00 88.96
MW-10 01/26/90 0.55 1.1 0.15 1.5 ----5.7 ------96.67 7.89 0.00 88.78
MW-10 11/14/90 0.074 ND ND 0.111 ----ND ------96.67 8.14 0.00 88.53
MW-10 04/23/91 0.0435 ND 0.0086 0.0807 ----1.4 ------96.67 7.96 0.00 88.71
MW-10 07/11/91 0.0056 ND ND 0.0352 ----1.78 ------96.67 7.38 0.00 89.29
MW-10 10/01/91 0.0512 0.0091 0.005 0.194 ----0.250 ------96.67 7.99 0.00 88.68
MW-10 01/01/92 0.0779 0.0178 0.0333 0.242 ----0.470 ------96.67 7.50 0.00 89.17
WELL WAS DESTROYED DURING DEMOLITION ACTIVITIES BY THE OFFSITE PROPERTY OWNERS
WELL WAS DESTROYED DURING DEMOLITION ACTIVITIES BY THE OFFSITE PROPERTY OWNERS
WELL WAS DESTROYED DURING DEMOLITION ACTIVITIES BY THE OFFSITE PROPERTY OWNERS
71887 Tables 1SA25 2025_V0 8/14
Table 1
Current and Historical Groundwater Gauging and Analytical Results
Former Chevron Station No. 7-1887
2003 S. Washington Boulevard, Ogden, Utah
Sample Location Date Benzene Toluene Ethyl-Benzene Total Xylenes Naphthalene MTBE Total TPH TPH-GRO
TPH-DRO
w/o SGC
TPH-DRO
w/SGC TOC DTW
Product
Thickness GWE Notes
MM/DD/YY (mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(feet)1 (feet btoc)(feet)(feet)
0.005 1.0 0.7 10 0.700 0.200 -- 1 1 1
0.300 3.0 4 10 0.700 0.200 -- 10 10 10
DERR ISL
RBCA Tier 1 SL Not Applicable
MW-10 04/01/92 0.0386 ND 0.0032 0.165 ----0.600 ------96.67 7.59 0.00 89.08
MW-10 07/01/92 0.0395 ND 0.0264 0.132 ----0.330 ------96.67 7.66 0.00 89.01
MW-10 10/01/92 0.0922 ND 0.0056 0.0943 ----0.365 ------96.67 7.92 0.00 88.75
MW-10 01/21/93 0.081 0.01 0.029 0.17 ----1.2 ------96.67 7.50 0.00 89.17
MW-10 04/26/93 0.11 0.031 0.15 0.68 ----2.9 ------96.67 6.90 0.00 89.77
MW-10 07/20/93 0.14 0.012 0.062 0.63 ----2.3 ------96.67 7.25 0.00 89.42
MW-10 10/27/93 0.065 0.011 0.039 0.32 ----1.8 ------96.67 7.51 0.00 89.16
MW-10 01/26/94 0.06 0.003 0.027 0.14 ----1.3 ------96.67 7.70 0.00 88.97
MW-10 04/29/94 0.014 0.0057 0.063 0.15 ----2.1 ------96.67 6.85 0.00 89.82
MW-10 07/28/94 0.047 0.0034 0.028 0.22 ----2.1 ------96.67 7.79 0.00 88.88
MW-10 12/01/07
MW-11 08/27/90 6.04 8.93 1.18 8.26 ----79 ------96.67 9.04 0.00 87.63
MW-11 04/23/91 4.42 6.95 0.685 9.81 ----245 ------96.67 9.78 0.00 86.89
MW-11 07/11/91 1.34 2.70 0.399 3.8 ----81.5 ------96.67 8.73 0.00 87.94
MW-11 01/01/92 3.56 6.25 1.29 7.43 ----39.2 ------96.67 9.08 0.00 87.59
MW-11 07/01/92 2.48 5.70 1.56 8.18 ----59.3 ------96.67 9.13 0.00 87.54
MW-11 04/26/93 2.80 8.60 1.6 9.90 ----43 ------96.67 8.30 0.00 88.37
MW-11 07/20/93 1.60 6.20 1.7 12 ----58 ------96.67 8.65 0.00 88.02
MW-11 10/27/93 1.80 6.20 1.5 9.1 ----42 ------96.67 9.20 0.00 87.47
MW-11 01/26/94 2.60 9.00 3.4 22 ----130 ------96.67 9.38 0.00 87.29
MW-11 04/29/94 1.40 6.30 3.0 19 ----180 ------96.67 8.16 0.00 88.51
MW-11 07/28/94 1.20 3.10 0.96 7.3 ----40 ------96.67 9.44 0.00 87.23
MW-11 12/13/07 0.001 0.03 0.033 0.12 0.006 <0.0005 --4.4 --18 96.67 9.95 0.00 86.72
MW-11 06/03/08 <0.0005 0.002 0.042 0.068 0.005 <0.0005 --4 11 --96.67 9.90 0.00 86.77
MW-11 12/01/08 0.009 0.011 0.039 0.11 0.01 <0.0005 --5.4 26 --96.67 11.41 0.00 85.26
MW-11 06/01/09 0.0008 0.0006 0.016 0.025 0.003 <0.0005 --2.8 22 --96.67 10.54 0.00 86.13
MW-11 11/30/09 0.18 0.037 0.068 0.087 0.008 <0.0005 --7.6 27 --96.67 12.06 0.00 84.61
MW-11 06/03/10 0.066 0.052 0.034 0.096 0.011 <0.0005 --1.8 --19 96.67 10.60 0.00 86.07
MW-11 03/14/11 <0.0005 0.0006 0.004 0.014 0.003 <0.0005 --0.340 --4.8 96.67 9.35 0.00 87.32
MW-11 09/14/11 0.0007 <0.0005 0.006 0.002 0.001 <0.0005 --0.310 --2.2 96.67 10.68 0.00 85.99
MW-11 03/14/12 <0.0005 <0.0005 <0.0005 <0.0005 <0.001 <0.0005 --0.130 --7.8 99.08 13.05 0.00 86.03 Surveyed 11/11
MW-11 09/11/12 0.002 0.0005 0.001 0.0008 <0.001 <0.0005 --0.110 --1.4 99.08 13.45 0.00 85.63
MW-11 03/12/13 <0.0005 <0.0005 <0.0005 <0.0005 <0.001 <0.0005 --0.034 --1.4 99.08 14.10 0.00 84.98
MW-11 09/19/13 0.0009 0.003 0.003 0.009 0.002 <0.0005 --0.150 --0.670 99.08 12.10 0.00 86.98
MW-11 04/07/14 <0.0005 <0.0005 <0.0005 0.0006 <0.001 <0.0005 --<0.022 --0.066 99.08 12.38 0.00 86.70
MW-11 07/21/14 <0.0005 <0.0005 <0.0005 <0.0005 <0.001 <0.0005 --<0.022 --0.440 99.08 7.51 0.00 91.57
MW-11 09/09/15 <0.0005 <0.0005 <0.0005 <0.0005 <0.001 <0.0005 --<0.022 --1.2 99.08 7.85 0.00 91.23
MW-11 05/01/17 <0.0005 <0.0005 <0.0005 <0.0005 <0.001 <0.0005 --<0.022 --<0.045 99.08 9.36 0.00 89.72
MW-11 09/06/17 0.001 <0.0005 <0.0005 <0.0005 <0.001 <0.0005 --0.031 --<0.045 99.08 11.35 0.00 87.73
MW-11 04/06/21 99.08 12.50 0.00 86.58
MW-11 09/14/21 0.00217 0.000736 J 0.00208 0.00249 J 0.00157 J <0.000101 --0.727 0.334 --99.08 11.80 0.00 87.28
MW-11 03/30/22 <0.0000941 <0.000278 <0.000137 <0.000174 <0.001 <0.000101 --<0.0314 0.188 --99.08 11.58 0.00 87.50
MW-11 06/09/22 99.08 11.47 0.00 87.61
MW-11 08/10/22 0.000206 J <0.000278 <0.000137 <0.000174 <0.001 <0.000101 --<0.0314 0.701 --99.08 11.77 0.00 87.31
MW-11 05/16/23 <0.0000941 <0.000278 <0.000137 <0.000174 <0.00100 <0.000101 --<0.0314 <0.0247 <0.0247 99.08 8.69 0.00 90.39
MW-11 08/08/23 <0.0000941 <0.000278 <0.000137 <0.000174 <0.00100 <0.000101 --<0.0314 0.192 B 0.0538 B J 99.08 10.94 0.00 88.14
MW-11 04/15/24 <0.0000941 <0.000278 <0.000137 <0.000174 <0.00100 <0.000101 --0.0481 B J 0.0910 J <0.0247 99.08 8.11 0.00 90.97
MW-11 DUPLICATE 04/15/24 <0.0000941 <0.000278 <0.000137 <0.000174 <0.00100 <0.000101 --0.0334 B J 0.0690 J <0.0247 99.08 8.11 0.00 90.97
MW-11 09/04/24 <0.0000941 <0.000278 <0.000137 <0.000174 <0.00100 C3 <0.000101 --0.0588 B J 0.179 0.0591 B J 99.08 11.29 0.00 87.79
MW-11 DUPLICATE 09/04/24 <0.0000941 <0.000278 <0.000137 <0.000174 <0.00100 <0.000101 --0.0653 B J 0.195 0.254 B 99.08 11.29 0.00 87.79
MW-12 08/27/90 1.918 0.659 1.28 12 ----85 --------------
MW-12 11/14/90 1.06 ND 0.354 1.34 ----7.28 ------98.95 8.20 0.00 90.75
MW-12 04/23/91 0.423 0.0166 ND 1.64 ----19.6 ------98.95 9.60 0.00 89.35
MW-12 07/11/91 0.565 0.245 0.374 1.76 ----33.4 ------98.95 8.82 0.00 90.13
WELL WAS DESTROYED DURING DEMOLITION ACTIVITIES BY THE OFFSITE PROPERTY OWNERS
ONLY NATURAL ATTENUATION SAMPLES
ONLY NATURAL ATTENUATION SAMPLES
71887 Tables 1SA25 2025_V0 9/14
Table 1
Current and Historical Groundwater Gauging and Analytical Results
Former Chevron Station No. 7-1887
2003 S. Washington Boulevard, Ogden, Utah
Sample Location Date Benzene Toluene Ethyl-Benzene Total Xylenes Naphthalene MTBE Total TPH TPH-GRO
TPH-DRO
w/o SGC
TPH-DRO
w/SGC TOC DTW
Product
Thickness GWE Notes
MM/DD/YY (mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(feet)1 (feet btoc)(feet)(feet)
0.005 1.0 0.7 10 0.700 0.200 -- 1 1 1
0.300 3.0 4 10 0.700 0.200 -- 10 10 10
DERR ISL
RBCA Tier 1 SL Not Applicable
MW-12 10/01/91 0.57 0.0337 ND 1.70 ----12.6 ------98.95 9.65 0.00 89.30
MW-12 01/01/92 0.789 0.188 0.593 1.66 ----17.6 ------98.95 8.96 0.00 89.99
MW-12 04/01/92 0.334 0.0107 ND 0.698 ----6.2 ------98.95 9.12 0.00 89.83
MW-12 07/01/92 0.335 0.0346 0.219 0.901 ----4.05 ------98.95 9.18 0.00 89.77
MW-12 10/01/92 0.375 ND ND 0.241 ----2.18 ------98.95 9.60 0.00 89.35
MW-12 04/26/93 0.54 0.046 0.066 0.3 ----3 ------98.95 8.30 0.00 90.65
MW-12 07/20/93 2.1 0.3 0.29 1.2 ----8 ------98.95 8.68 0.00 90.27
MW-12 10/27/93 0.34 0.13 0.45 1.7 ----12 ------98.95 9.16 0.00 89.79
MW-12 01/26/94 0.37 0.032 0.23 0.88 ----6.4 ------98.95 9.39 0.00 89.56
MW-12 04/29/94 0.092 0.0081 0.11 0.17 ----3.9 ------98.95 8.22 0.00 90.73
MW-12 07/28/94 0.23 0.0097 0.14 0.17 ----5 ------98.95 9.39 0.00 89.56
MW-12 06/01/09
MW-12 11/30/09
MW-12 06/03/10
MW-12 03/14/11
MW-12 09/14/11
MW-12 03/14/12
MW-12 09/11/12 <0.0005 <0.0005 <0.0005 <0.0005 <0.001 <0.0005 <0.022 <0.050 --98.95 13.57 0.00 85.38
MW-12 03/12/13
MW-12 09/19/13 <0.0005 <0.0005 <0.0005 <0.0005 <0.001 <0.0005 --<0.022 --0.11 98.95 12.25 0.00 86.70
MW-12 04/07/14 <0.0005 <0.0005 <0.0005 <0.0005 <0.001 <0.0005 --<0.022 --0.12 98.95 12.70 0.00 86.25
MW-12 07/21/14 <0.0005 <0.0005 <0.0005 <0.0005 <0.001 <0.0005 --<0.022 --0.38 98.95 11.43 0.00 87.52
MW-12 09/09/15 <0.0005 <0.0005 <0.0005 <0.0005 <0.001 <0.0005 --<0.022 --0.16 98.95 11.45 0.00 87.50
MW-12 03/30/22
MW-13 08/27/90 ND ND ND ND ----ND --------------
MW-13 11/14/90 ND ND ND ND ----ND ------97.94 9.05 0.00 88.89
MW-13 04/23/91 ND ND ND ND ----ND ------97.94 8.78 0.00 89.16
MW-13 07/11/91 ND ND ND ND ----ND ------97.94 9.20 0.00 88.74
MW-13 10/01/91 ND ND ND ND ----ND ------97.94 8.83 0.00 89.11
MW-13 04/01/92 ND ND ND ND ----ND ------97.94 8.31 0.00 89.63
MW-13 10/01/92 ND ND ND ND ----ND ------97.94 8.75 0.00 89.19
MW-13 01/21/93 --------------------97.94 8.35 0.00 89.59
MW-13 04/26/93 ND ND ND ND ----ND ------97.94 7.50 0.00 90.44
MW-13 07/20/93 --------------------97.94 7.92 0.00 90.02
MW-13 10/27/93 ND ND ND ND ----ND ------97.94 8.38 0.00 89.56
MW-13 01/26/94 --------------------97.94 8.48 0.00 89.46
MW-13 04/29/94 ND ND ND ND ----ND ------97.94 7.49 0.00 90.45
MW-13 07/28/94 --------------------97.94 8.61 0.00 89.33
MW-13 12/01/07
MW-14 08/27/90 0.325 0.25 0.444 2.06 ----12.3 --------------
MW-14 11/14/90 0.658 ND 0.304 1.84 ----5.79 ------98.58 9.46 0.00 89.12
MW-14 04/23/91 0.0082 0.0202 ND 0.331 ----3.81 ------98.58 9.14 0.00 89.44
MW-14 07/11/91 0.0081 0.0839 ND 0.763 ----3.61 ------98.58 8.26 0.00 90.32
MW-14 10/01/91 0.0089 0.0865 0.0927 1.43 ----2.47 --------------
MW-14 01/01/92 ND 0.208 0.422 2.49 ----5.53 ------98.58 8.54 0.00 90.04
MW-14 04/01/92 0.0026 0.0916 0.0736 0.831 ----6.98 ------98.58 8.61 0.00 89.97
MW-14 07/01/92 0.005 0.106 0.3 1.54 ----4.99 ------98.58 8.69 0.00 89.89
MW-14 10/01/92 0.028 ND ND 1.47 ----6.03 ------98.58 9.07 0.00 89.51
MW-14 01/21/93 0.096 0.057 0.21 1.0 ----5.1 ------98.58 8.68 0.00 89.90
MW-14 04/26/93 ND 0.034 0.098 0.46 ----2.1 ------98.58 7.77 0.00 90.81
MW-14 07/20/93 0.026 0.026 0.12 6.11 ----3.3 ------98.58 8.18 0.00 90.40
MW-14 10/27/93 0.003 0.025 0.092 0.44 ----2.5 ------98.58 8.72 0.00 89.86
MW-14 01/26/94 ND 0.034 0.12 0.86 ----5.4 ------98.58 8.82 0.00 89.76
MW-14 04/29/94 0.016 0.026 0.07 0.33 ----2.2 ------98.58 7.68 0.00 90.90
UNABLE TO LOCATE
UNABLE TO LOCATE
UNABLE TO LOCATE
UNABLE TO LOCATE
INACCESSIBLE
UNABLE TO LOCATE
UNABLE TO LOCATE
DRY
WELL WAS DESTROYED DURING DEMOLITION ACTIVITIES BY THE OFFSITE PROPERTY OWNERS
71887 Tables 1SA25 2025_V0 10/14
Table 1
Current and Historical Groundwater Gauging and Analytical Results
Former Chevron Station No. 7-1887
2003 S. Washington Boulevard, Ogden, Utah
Sample Location Date Benzene Toluene Ethyl-Benzene Total Xylenes Naphthalene MTBE Total TPH TPH-GRO
TPH-DRO
w/o SGC
TPH-DRO
w/SGC TOC DTW
Product
Thickness GWE Notes
MM/DD/YY (mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(feet)1 (feet btoc)(feet)(feet)
0.005 1.0 0.7 10 0.700 0.200 -- 1 1 1
0.300 3.0 4 10 0.700 0.200 -- 10 10 10
DERR ISL
RBCA Tier 1 SL Not Applicable
MW-14 07/28/94 0.039 0.02 0.14 0.81 ----5.2 ------98.58 8.92 0.00 89.66
MW-14 12/01/07
MW-15 08/27/90 ND ND ND ND ----ND --------------
MW-15 11/14/90 ND ND ND ND ----ND ------99.89 10.43 0.00 89.46
MW-15 04/23/91 ND ND ND ND ----ND ------99.89 9.91 0.00 89.98
MW-15 10/01/91 ND ND ND ND ----ND ------99.89 10.00 0.00 89.89
MW-15 04/01/92 ND ND ND ND ----ND ------99.89 9.31 0.00 90.58
MW-15 10/01/92 ND ND ND ND ----ND ------99.89 9.82 0.00 90.07
MW-15 01/21/93 --------------------99.89 9.41 0.00 90.48
MW-15 04/26/93 ND ND ND ND ----ND ------99.89 8.40 0.00 91.49
MW-15 04/26/93 ND ND ND ND ----ND ------99.89 8.40 0.00 91.49
MW-15 07/20/93 --------------------99.89 8.78 0.00 91.11
MW-15 10/27/93 ND ND ND ND ----ND ------99.89 9.40 0.00 90.49
MW-15 01/26/94 --------------------99.89 9.59 0.00 90.30
MW-15 04/29/94 ND ND ND ND ----ND ------99.89 8.30 0.00 91.59
MW-15 07/28/94 --------------------99.89 9.66 0.00 90.23
MW-15 12/01/07
MW-16 11/14/90 ND ND ND ND ----ND --------------
MW-16 04/23/91 ND ND ND ND ----ND ------95.67 7.54 0.00 88.13
MW-16 10/01/91 0.0011 ND ND ND ----ND --------------
MW-16 04/01/92 0.0162 ND ND ND ----ND ------95.67 7.21 0.00 88.46
MW-16 07/01/92 0.0252 ND ND ND ----ND ------95.67 7.21 0.00 88.46
MW-16 10/01/92 0.027 ND ND ND ----0.236 ------95.67 7.41 0.00 88.26
MW-16 01/21/93 --------------------95.67 7.12 0.00 88.55
MW-16 04/26/93 0.032 0.002 ND 0.002 ----0.26 ------95.67 7.45 0.00 88.22
MW-16 07/22/93 --------------------95.67 6.94 0.00 88.73
MW-16 10/27/93 0.017 0.0007 ND ND ----0.18 ------95.67 7.14 0.00 88.53
MW-16 01/26/94 --------------------95.67 7.30 0.00 88.37
MW-16 04/29/94 0.0015 ND ND ND ----0.06 ------95.67 6.71 0.00 88.96
MW-16 07/28/94 --------------------95.67 7.35 0.00 88.32
MW-16 12/01/07
MW-17 11/29/90 ND ND ND ND ----ND --------------
MW-17 04/23/91 0.0087 ND ND 0.0072 ----ND ------95.82 7.59 0.00 88.23
MW-17 07/11/92 0.0214 ND ND ND ----ND ------95.82 7.20 0.00 88.62
MW-17 10/01/91 0.0182 ND ND ND ----ND --------------
MW-17 01/01/92 0.054 ND ND ND ----ND ------95.82 7.12 0.00 88.70
MW-17 04/01/92 0.0354 ND ND ND ----ND ------95.82 7.27 0.00 88.55
MW-17 07/01/92 0.0281 ND ND ND ----ND ------95.82 7.25 0.00 88.57
MW-17 10/01/92 0.0182 ND ND ND ----0.29 ------95.82 7.44 0.00 88.38
MW-17 01/21/93 0.034 0.9 ND 0.001 ----0.73 ------95.82 7.12 0.00 88.70
MW-17 04/26/93 0.042 0.002 0.0005 0.002 ----0.39 ------95.82 6.81 0.00 89.01
MW-17 07/22/93 0.085 0.008 0.014 0.016 ----0.55 ------95.82 7.00 0.00 88.82
MW-17 10/27/93 0.024 0.002 0.001 0.001 ----0.46 ------95.82 7.18 0.00 88.64
MW-17 01/26/94 0.062 ND ND 0.0008 ----0.67 ------95.82 7.36 0.00 88.46
MW-17 04/29/94 0.055 ND ND 0.0011 ----0.60 ------95.82 6.78 0.00 89.04
MW-17 07/28/94 0.012 0.001 ND ND ----0.31 ------95.82 7.34 0.00 88.48
MW-17 12/01/07
MW-18 11/29/90 ND ND ND ND ----ND --------------
MW-18 04/23/91 0.0087 ND ND 0.0095 ----ND ------96.01 7.75 0.00 88.26
MW-18 07/11/92 ND ND ND ND ----ND ------96.01 7.32 0.00 88.69
MW-18 10/01/91 ND ND ND ND ----ND ------96.01 ----96.01
MW-18 01/01/92 0.0123 ND ND ND ----ND ------96.01 7.31 0.00 88.70
MW-18 04/01/92 ND ND ND ND ----ND ------96.01 7.43 0.00 88.58
MW-18 07/01/92 ND ND ND ND ----ND ------96.01 7.42 0.00 88.59
WELL WAS DESTROYED DURING DEMOLITION ACTIVITIES BY THE OFFSITE PROPERTY OWNERS
WELL WAS DESTROYED DURING DEMOLITION ACTIVITIES BY THE OFFSITE PROPERTY OWNERS
WELL WAS DESTROYED DURING DEMOLITION ACTIVITIES BY THE OFFSITE PROPERTY OWNERS
WELL WAS DESTROYED DURING DEMOLITION ACTIVITIES BY THE OFFSITE PROPERTY OWNERS
71887 Tables 1SA25 2025_V0 11/14
Table 1
Current and Historical Groundwater Gauging and Analytical Results
Former Chevron Station No. 7-1887
2003 S. Washington Boulevard, Ogden, Utah
Sample Location Date Benzene Toluene Ethyl-Benzene Total Xylenes Naphthalene MTBE Total TPH TPH-GRO
TPH-DRO
w/o SGC
TPH-DRO
w/SGC TOC DTW
Product
Thickness GWE Notes
MM/DD/YY (mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(feet)1 (feet btoc)(feet)(feet)
0.005 1.0 0.7 10 0.700 0.200 -- 1 1 1
0.300 3.0 4 10 0.700 0.200 -- 10 10 10
DERR ISL
RBCA Tier 1 SL Not Applicable
MW-18 10/01/92 0.0013 ND ND ND ----ND ------96.01 7.61 0.00 88.40
MW-18 01/21/93 0.001 ND ND ND ----0.052 ------96.01 7.30 0.00 88.71
MW-18 04/26/93 0.008 0.003 0.0005 0.002 ----0.071 ------96.01 6.90 0.00 89.11
MW-18 07/22/93 ND ND ND ND ----ND ------96.01 7.16 0.00 88.85
MW-18 10/27/93 ND 0.0005 ND ND ----ND ------96.01 7.34 0.00 88.67
MW-18 01/26/94 0.003 ND ND ND ----0.080 ------96.01 7.50 0.00 88.51
MW-18 04/29/94 ND ND ND ND ----ND ------96.01 6.87 0.00 89.14
MW-18 07/28/94 ND ND ND ND ----ND ------96.01 7.50 0.00 88.51
MW-18 12/01/07
MW-19 11/29/90 ND ND ND ND ----ND --------------
MW-19 04/23/91 ND ND ND ND ----ND ------96.82 8.26 0.00 88.56
MW-19 10/01/91 ND ND ND ND ----ND ------96.82 8.30 0.00 88.52
MW-19 04/01/92 ND ND ND ND ----ND ------96.82 7.86 0.00 88.96
MW-19 10/01/92 ND ND ND ND ----ND ------96.82 8.24 0.00 88.58
MW-19 05/26/93 0.012 ND ND ND ----ND ------96.82 7.15 0.00 89.67
MW-19 07/20/93 --------------------96.82 7.55 0.00 89.27
MW-19 10/27/93 ND ND ND ND ----ND ------96.82 7.89 0.00 88.93
MW-19 01/26/93 --------------------96.82 7.99 0.00 88.83
MW-19 04/29/94 ND ND ND ND ----ND ------96.82 7.18 0.00 89.64
MW-19 07/28/94 --------------------96.82 8.14 0.00 88.68
MW-19 12/01/07
MW-20 11/29/90 ND ND ND ND ----ND --------------
MW-20 04/23/91 ND ND ND ND ----ND ------95.69 7.18 0.00 88.51
MW-20 10/01/91 ND ND ND ND ----ND ------95.69 7.19 0.00 88.50
MW-20 04/01/92 ND ND ND ND ----ND ------95.69 6.78 0.00 88.91
MW-20 10/01/92 ND ND 0.0014 ND ----ND ------95.69 7.12 0.00 88.57
MW-20 10/11/94 ND ND ND ND ----ND ------95.69 6.94 0.00 88.75
MW-20 07/25/95
MW-21 08/20/02 0.012 0.0012 0.0024 <0.005 <0.005 <0.0025 1.2 ------97.59 8.09 0.00 89.50
MW-21 11/05/02 0.006 0.00053 0.0014 <0.005 0.0051 <0.0025 0.67 ------97.59 8.47 0.00 89.12
MW-21 03/19/03 0.00092 <0.002 0.0016 <0.005 0.0028 <0.0025 0.54 ------97.59 8.37 0.00 89.22
MW-21 06/17/03 0.002 ND ND ND ND ND 0.54 ------97.59 8.00 0.00 89.59
MW-21 09/30/03 <0.0005 <0.0005 <0.0005 <0.005 <0.001 <0.0005 0.12 ------97.59 8.29 0.00 89.30
MW-21 11/25/03 <0.0005 <0.0005 <0.0005 <0.005 <0.001 <0.0005 0.11 ------97.59 8.37 0.00 89.22
MW-21 12/01/07
MW-22 08/20/02 0.059 0.0041 0.0016 0.018 0.0044 <0.0025 0.35 ------96.98 7.62 0.00 89.36
MW-22 11/05/02 0.0071 <0.0005 <0.0005 <0.0015 <0.001 <0.0025 0.095 ------96.98 7.94 0.00 89.04
MW-22 03/19/03 <0.0005 <0.0005 <0.0005 <0.0015 <0.001 <0.0025 <0.050 ------96.98 7.82 0.00 89.16
MW-22 06/17/03 ND ND ND ND ND ND ND ------96.98 7.45 0.00 89.53
MW-22 09/30/03 <0.0005 <0.0005 <0.0005 <0.0005 <0.001 <0.0005 <0.050 ------96.98 7.76 0.00 89.22
MW-22 11/25/03 <0.0005 <0.0005 <0.0005 <0.0005 <0.001 <0.0005 <0.050 ------96.98 7.83 0.00 89.15
MW-22 12/01/07
MW-23 01/12/17 0.004 <0.003 0.01 0.02 0.11 <0.003 --5.3 --2.2 98.39 11.70 0.00 86.69
MW-23 05/01/17 0.14 0.012 0.022 0.092 0.17 <0.003 --8.3 --7.9 98.39 10.02 0.00 88.37
MW-23 09/07/17 0.17 0.01 0.008 0.087 0.15 <0.003 --8.9 --3.6 98.39 11.43 0.00 86.96
MW-23 12/12/19 0.140 J*0.007 0.009 0.065 0.19 <0.001 --5.3 --0.57 98.39 11.48 0.00 86.91
MW-23 04/06/21 98.39 12.29 0.00 86.10
MW-23 06/17/21
MW-23 09/14/21 0.172 0.00843 0.00666 0.0643 0.114 <0.000101 --1.44 5.65 --99.01 11.68 0.00 87.33
MW-23 12/28/21 0.0322 0.00365 0.00605 0.0376 0.160 <0.000101 --7.49 3.13 --99.01 12.13 0.00 86.88
MW-23 03/30/22 0.0491 0.00659 0.00974 0.0463 0.0869 <0.000101 --4.80 4.66 --99.01 11.45 0.00 87.56
MW-23 DUPLICATE 03/30/22 0.0471 0.00634 0.00961 0.0440 0.0858 <0.000101 --4.28 4.47 --99.01 11.45 0.00 87.56
MW-23 06/09/22 0.0947 0.00642 0.00644 0.0454 0.104 <0.000101 --5.97 1.58 --99.01 11.42 0.00 87.59
MW-23 DUPLICATE 06/09/22 0.0926 0.00656 0.00669 0.0464 0.108 <0.000101 --5.49 1.75 --99.01 11.42 0.00 87.59
PERMEABLE FILLED BORINGS WITH SULFATE ADDED CROSSGRADIENT AND DOWNGRADIENT
WELL WAS DESTROYED DURING DEMOLITION ACTIVITIES BY THE OFFSITE PROPERTY OWNERS
WELL WAS DESTROYED DURING DEMOLITION ACTIVITIES BY THE OFFSITE PROPERTY OWNERS
WELL WAS DESTROYED DURING DEMOLITION ACTIVITIES BY THE OFFSITE PROPERTY OWNERS
WELL WAS DESTROYED DURING DEMOLITION ACTIVITIES BY THE OFFSITE PROPERTY OWNERS
ONLY NATURAL ATTENUATION SAMPLES
WELL WAS DESTROYED DURING DEMOLITION ACTIVITIES BY THE OFFSITE PROPERTY OWNERS
71887 Tables 1SA25 2025_V0 12/14
Table 1
Current and Historical Groundwater Gauging and Analytical Results
Former Chevron Station No. 7-1887
2003 S. Washington Boulevard, Ogden, Utah
Sample Location Date Benzene Toluene Ethyl-Benzene Total Xylenes Naphthalene MTBE Total TPH TPH-GRO
TPH-DRO
w/o SGC
TPH-DRO
w/SGC TOC DTW
Product
Thickness GWE Notes
MM/DD/YY (mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(feet)1 (feet btoc)(feet)(feet)
0.005 1.0 0.7 10 0.700 0.200 -- 1 1 1
0.300 3.0 4 10 0.700 0.200 -- 10 10 10
DERR ISL
RBCA Tier 1 SL Not Applicable
MW-23 08/11/22 0.125 0.00478 0.00375 0.0250 0.0248 <0.000101 --3.11 0.749 --99.01 11.69 0.00 87.32
MW-23 05/17/23 0.0420 0.00528 0.00676 0.0502 0.117 E <0.000101 --3.51 0.930 0.521 99.01 9.35 0.00 89.66
MW-23 08/09/23 0.0270 0.00357 0.00700 0.0517 0.107 <0.000101 --3.27 1.410 1.44 99.01 11.01 0.00 88.00
MW-23 04/16/24 0.00530 0.000586 J 0.000813 J 0.00425 0.00732 <0.000101 -- 0.456 0.249 B 0.0748 J 99.01 9.31 0.00 89.70
MW-23 09/04/24 0.0262 0.00221 0.00260 0.0186 0.0426 <0.000101 --3.36 0.899 0.624 B 99.01 11.23 0.00 87.78
MW-23 05/06/25
0.0510 0.00360 0.00480 0.0280 0.0790 <0.0015 --4.10 -- 0.480 99.01 10.72 0.00 88.29
MW-24 01/12/17 0.003 0.001 0.002 0.004 0.014 <0.0005 --0.31 --0.056 99.01 12.25 0.00 86.76
MW-24 05/01/17 0.01 0.008 0.028 0.035 0.041 <0.0005 --3.6 --0.26 99.01 10.48 0.00 88.53
MW-24 09/07/17 0.01 0.004 0.007 0.015 0.032 <0.0005 --2.6 --0.3 99.01 11.93 0.00 87.08
MW-24 12/12/19 0.017 J*0.007 0.004 J 0.016 J 0.057 <0.001 --3.5 --0.56 99.01 12.02 0.00 86.99
MW-24 04/06/21 99.01 12.85 0.00 86.16
MW-24 06/17/21
MW-24 09/14/21 0.0145 0.00661 0.00434 0.0129 0.0846 <0.000101 --1.35 3.35 --99.01 12.21 0.00 86.80
MW-24 12/28/21 0.0138 0.00414 0.00194 0.00588 0.019 <0.000101 --1.13 1.76 --99.01 12.68 0.00 86.33
MW-24 03/30/22 0.0109 0.00386 0.00221 0.00599 0.051 <0.000101 --1.90 1.08 --99.01 12.52 0.00 86.49
MW-24 06/09/22 0.0119 0.00348 0.00262 0.00698 0.0543 <0.000101 --2.73 1.23 --99.01 11.95 0.00 87.06
MW-24 08/11/22 0.0216 0.00563 0.00503 0.00833 0.0522 <0.000101 --2.88 1.32 --99.01 12.22 0.00 86.79
MW-24 05/17/23 0.00955 0.00343 0.00542 0.00536 0.0609 <0.000101 --1.12 1.20 0.345 99.01 9.87 0.00 89.14
MW-24 08/09/23 0.0133 0.00593 0.01270 0.01290 0.0395 <0.000101 --2.04 2.66 2.14 99.01 11.53 0.00 87.48
MW-24 04/16/24 0.00785 0.00282 0.00253 0.00446 0.0205 <0.000101 -- 0.957 0.883 0.308 99.01 9.94 0.00 89.07
MW-24 09/04/24 0.0173 0.00225 0.00311 0.00517 0.0130 <0.000101 --2.31 1.49 0.593 B 99.01 11.78 0.00 87.23
MW-24 05/06/25 0.0067 J <0.0025 <0.0025 <0.0025 <0.01 <0.015 --1.10 --<0.5 99.01 11.3 0.00 87.71
MW-25 01/12/17 0.01 0.0006 0.0006 0.004 0.007 <0.0005 --0.71 --0.085 97.56 10.90 0.00 86.66
MW-25 05/01/17 0.037 0.005 0.017 0.041 0.018 <0.0005 --2.4 --0.17 97.56 9.22 0.00 88.34
MW-25 09/07/17 0.018 0.002 0.001 0.014 0.008 <0.0005 --0.990 --0.06 97.56 10.62 0.00 86.94
MW-25 12/12/19 0.004 J <0.0002 <0.0004 <0.001 <0.001 <0.0002 --0.200 --<0.052 97.56 10.68 0.00 86.88
MW-25 04/06/21 97.56 11.49 0.00 86.07
MW-25 09/14/21 0.000138 J <0.000278 <0.000137 <0.000174 <0.001 <0.000101 --0.0314 J <0.112 --97.56 10.86 0.00 86.70
MW-25 03/31/22 <0.0000941 <0.000278 <0.000137 <0.000174 <0.001 <0.000101 --0.106 B 0.11 --97.56 11.30 0.00 86.26
MW-25 06/09/22 97.56 10.64 0.00 86.92
MW-25 08/11/22 <0.0000941 <0.000278 <0.000137 <0.000174 <0.001 <0.000101 --0.107 0.0696 J --97.56 10.88 0.00 86.68
MW-25 05/17/23 0.0128 0.000624 J 0.00152 0.00522 0.00777 <0.000101 --0.608 0.147 0.504 97.56 8.60 0.00 88.96
MW-25 08/09/23 0.00307 <0.000278 <0.000137 <0.000174 <0.00100 <0.000101 --0.285 0.505 0.0912 B J 97.56 10.22 0.00 87.34
MW-25 04/16/24 0.00384 <0.000278 0.000188 J <0.000174 <0.00100 <0.000101 --0.264 B 0.176 0.0333 J 97.56 8.68 0.00 88.88
MW-25 09/04/24 <0.0000941 <0.000278 <0.000137 <0.000174 <0.00100 C3 <0.000101 --0.246 B 0.205 0.0567 B J 97.56 10.45 0.00 87.11
MW-26 12/12/19 <0.0002 <0.0002 <0.0004 <0.001 <0.001 <0.0002 --0.87 --<0.046 --10.63 0.00 --
MW-26 04/06/21 -- 11.46 0.00 --
MW-26 09/14/21 <0.0000941 <0.000278 <0.000137 <0.000174 <0.001 <0.000101 --0.0249 J <0.0314 ---- 10.85 0.00 --
MW-26 03/31/22 <0.0000941 <0.000278 <0.000137 <0.000174 <0.001 <0.000101 --<0.0314 0.0993 J ---- 10.70 0.00 --
MW-26 06/09/22 -- 10.56 0.00 --
MW-26 08/10/22 <0.0000941 <0.000278 <0.000137 <0.000174 <0.001 <0.000101 --<0.0314 0.148 ----10.84 0.00 --
MW-26 05/16/23 0.00210 <0.000278 <0.000137 <0.000174 0.00195 J <0.000101 --<0.0314 0.0516 J 0.0516 J -- 8.57 0.00 --
MW-26 08/09/23 0.00493 <0.000278 <0.000137 <0.000174 <0.00100 <0.000101 --0.14 0.312 B 0.0659 B J -- 10.17 0.00 --
MW-26 04/16/24 0.00269 <0.000278 <0.000137 <0.000174 <0.00100 <0.000101 --0.123 B 0.150 B <0.0247 -- 8.66 0.00 --
MW-26 09/04/24 <0.0000941 <0.000278 <0.000137 <0.000174 <0.00100 C3 <0.000101 -- 0.110 B 0.144 0.0621 B J -- 10.36 0.00 --
MW-27 12/12/19 <0.0002 <0.0002 <0.0004 <0.001 <0.001 <0.0002 --0.14 --<0.046 --11.82 0.00 --`
MW-27 04/06/21 -- 12.60 0.00 --
MW-27 DUPLICATE 04/06/21 -- 12.60 0.00 --
MW-27 09/14/21 <0.0000941 <0.000278 <0.000137 <0.000174 <0.001 <0.000101 --0.0763 J <0.0314 ----11.96 0.00 --
MW-27 03/31/22 <0.0000941 <0.000278 <0.000137 <0.000174 <0.001 <0.000101 --<0.0314 0.0798 J ----11.75 0.00 --
MW-27 06/09/22 --11.76 0.00 --
MW-27 08/11/22 <0.0000941 <0.000278 <0.000137 <0.000174 <0.001 <0.000101 -- <0.0314 0.0366 J ----12.04 0.00 --
PERMEABLE FILLED BORINGS WITH SULFATE ADDED CROSSGRADIENT AND DOWNGRADIENT
ONLY NATURAL ATTENUATION SAMPLES
ONLY NATURAL ATTENUATION SAMPLES
ONLY NATURAL ATTENUATION SAMPLES
ONLY NATURAL ATTENUATION SAMPLES
ONLY NATURAL ATTENUATION SAMPLES
ONLY NATURAL ATTENUATION SAMPLES
ONLY NATURAL ATTENUATION SAMPLES
ONLY NATURAL ATTENUATION SAMPLES
71887 Tables 1SA25 2025_V0 13/14
Table 1
Current and Historical Groundwater Gauging and Analytical Results
Former Chevron Station No. 7-1887
2003 S. Washington Boulevard, Ogden, Utah
Sample Location Date Benzene Toluene Ethyl-Benzene Total Xylenes Naphthalene MTBE Total TPH TPH-GRO
TPH-DRO
w/o SGC
TPH-DRO
w/SGC TOC DTW
Product
Thickness GWE Notes
MM/DD/YY (mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(feet)1 (feet btoc)(feet)(feet)
0.005 1.0 0.7 10 0.700 0.200 -- 1 1 1
0.300 3.0 4 10 0.700 0.200 -- 10 10 10
DERR ISL
RBCA Tier 1 SL Not Applicable
MW-27 05/16/23 <0.0000941 <0.000278 <0.000137 <0.000174 <0.00100 <0.000101 -- <0.0314 <0.0247 <0.0247 -- 9.71 0.00 --
MW-27 08/09/23 <0.0000941 <0.000278 <0.000137 <0.000174 <0.00100 <0.000101 -- <0.0314 0.0677 B J 0.0670 B J -- 11.35 0.00 --
MW-27 04/16/24 <0.0000941 <0.000278 <0.000137 <0.000174 <0.00100 <0.000101 -- 0.0368 B J <0.0247 <0.0247 -- 9.80 0.00 --
MW-27 09/04/24 <0.0000941 <0.000278 <0.000137 <0.000174 <0.00100 <0.000101 -- 0.0461 B J 0.0604 J 0.0604 J -- 11.58 0.00 --
Notes:
1. Feet above reference benchmark
Total TPH = total petroleum hydrocarbons by Method USEPA 8015/610 Modified.
TPH-GRO = total petroleum hydrocarbons - gasoline range organics analyzed by USEPA Method 8015B Modified.
TPH-DRO = total petroleum hydrocarbons - diesel range organics analyzed by USEPA Method 8015B.
Benzene, toluene, ethylbenzene, total xylenes, naphthalene, and MTBE analyzed by USEPA Method 624, 8020, after 12/99 8021 B, and as of 6/17/03 8260B.
Acronyms and Abbreviations:
Bold = Result exceeds DERR ISL.
Shaded cell result exceed RBCA Tier 1 SL.
* = erroneous field reading
< = not detected at concentrations at or above the method detection limit. The method detection limit is listed in the analytical report.
-- = Not Applicable
btoc = below top of casing
DERR = Division of Environmental Response and Remediation
DERR ISL = DERR Initial Screening Level
DTW = depth to water
GWE = groundwater elevation, based on site benchmark corrected for product if present, using a specific gravity of 0.75
mg/L = milligram per liter
MTBE = methyl tertiary butyl ether
ND = not detected at concentrations at or above the method detection limit. The method detection limit is listed in the analytical report.
RBCA = Risk-Based Corrective Action
TOC = top of casing (assumed benchmark)
Qualifiers:
J = Estimated value. Result is above or equal to the Method Detection Limit (MDL or DL) and below the Limit of Quantitation (LOQ or RL)
J* = Drift continuing calibration criteria of 20 percent exceeded for benzene for some samples. Result is estimated.
B = The same analyte is found in the associated blank.
E = The analyte concentration exceeds the upper limit of the calibration range of the instrument established by the initialcalibration (ICAL).
RBCA Tier 1 SL = RBCA Tier 1 Screening Level. Only applicable when 1. No buildings, property boundaries or utility lines within 30 feet of the highest measured concentration of any contaminant that is
greater than the ISL but less than or equal to the Tier 1 SL, and, no water wells or surface water within 500 feet of highest measured concentration of any contaminant that is greater than the ISL but less
than or equal to the Tier 1 SL.
71887 Tables 1SA25 2025_V0 14/14
AECOM
756 E Winchester St, Ste 400
Murray, UT 84107
aecom.com

Attachment A
Groundwater Monitoring Field Forms

5
Attachment B
Laboratory Analytical Report
ANALYTICAL REPORT
PREPARED FOR
Attn: Wil Pineda
AECOM
756 Winchester Street
Suite 400
Salt Lake City, Utah 84107
Generated 5/19/2025 12:08:31 PM
JOB DESCRIPTION
Chevron 71887 - Little Ogden, UT
JOB NUMBER
280-207337-1
See page two for job notes and contact information.
Arvada CO 80002
4955 Yarrow Street
Eurofins Denver
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Eurofins Denver
Eurofins Denver is a laboratory within TestAmerica Laboratories, Inc., a company within Eurofins Environment Testing Group of Companies
Job Notes
This report may not be reproduced except in full, and with written approval from the laboratory. The results relate only to the
samples tested. For questions please contact the Project Manager at the e-mail address or telephone number listed on this
page.
The test results in this report relate only to the samples as received by the laboratory and will meet all requirements of the
methodology, with any exceptions noted. This report shall not be reproduced except in full, without the express written
approval of the laboratory. All questions should be directed to the Eurofins TestAmerica Project Manager.
Authorization
Generated
5/19/2025 12:08:31 PM
Authorized for release by
Cassie Servas, Project Manager
[e-mail]
[phone]
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Table of Contents
Client: AECOM
Project/Site: Chevron 71887 - Little Ogden, UT
Laboratory Job ID: 280-207337-1
Page 3 of 21
Eurofins Denver
5/19/2025
Cover Page . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1
Table of Contents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3
Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4
Case Narrative . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
Detection Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6
Method Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
Sample Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8
Client Sample Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
Surrogate Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11
QC Sample Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12
QC Association . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16
Chronicle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18
Certification Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19
Chain of Custody . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20
Receipt Checklists . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21
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Definitions/Glossary
Job ID: 280-207337-1Client: AECOM
Project/Site: Chevron 71887 - Little Ogden, UT
Qualifiers
GC/MS VOA
Qualifier Description
J Result is less than the RL but greater than or equal to the MDL and the concentration is an approximate value.
Qualifier
GC/MS Semi VOA
Qualifier Description
J Result is less than the RL but greater than or equal to the MDL and the concentration is an approximate value.
Qualifier
Glossary
These commonly used abbreviations may or may not be present in this report.
☼Listed under the "D" column to designate that the result is reported on a dry weight basis
Abbreviation
%R Percent Recovery
CFL Contains Free Liquid
CFU Colony Forming Unit
CNF Contains No Free Liquid
DER Duplicate Error Ratio (normalized absolute difference)
Dil Fac Dilution Factor
DL Detection Limit (DoD/DOE)
DL, RA, RE, IN Indicates a Dilution, Re-analysis, Re-extraction, or additional Initial metals/anion analysis of the sample
DLC Decision Level Concentration (Radiochemistry)
EDL Estimated Detection Limit (Dioxin)
LOD Limit of Detection (DoD/DOE)
LOQ Limit of Quantitation (DoD/DOE)
MCL EPA recommended "Maximum Contaminant Level"
MDA Minimum Detectable Activity (Radiochemistry)
MDC Minimum Detectable Concentration (Radiochemistry)
MDL Method Detection Limit
ML Minimum Level (Dioxin)
MPN Most Probable Number
MQL Method Quantitation Limit
NC Not Calculated
ND Not Detected at the reporting limit (or MDL or EDL if shown)
NEG Negative / Absent
POS Positive / Present
PQL Practical Quantitation Limit
PRES Presumptive
QC Quality Control
RER Relative Error Ratio (Radiochemistry)
RL Reporting Limit or Requested Limit (Radiochemistry)
RPD Relative Percent Difference, a measure of the relative difference between two points
TEF Toxicity Equivalent Factor (Dioxin)
TEQ Toxicity Equivalent Quotient (Dioxin)
TNTC Too Numerous To Count
Eurofins Denver
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Job Narrative
280-207337-1
Analytical test results meet all requirements of the associated regulatory program listed on the Accreditation/Certification Summary
Page unless otherwise noted under the individual analysis.Data qualifiers and/or narrative comments are included to explain any
exceptions,if applicable.
Matrix QC may not be reported if insufficient sample is provided or site-specific QC samples were not submitted.In these
situations,to demonstrate precision and accuracy at a batch level,a LCS/LCSD may be performed,unless otherwise
specified in the method.
Surrogate and/or isotope dilution analyte recoveries (if applicable)which are outside of the QC window are confirmed
unless attributed to a dilution or otherwise noted in the narrative.
Regulated compliance samples (e.g.SDWA,NPDES)must comply with the associated agency requirements/permits.
Receipt
The sample was received on 5/9/2025 9:05 AM.Unless otherwise noted below,the sample arrived in good condition,and,where
required,properly preserved and on ice.The temperature of the cooler at receipt time was 0.1°C.
GC/MS VOA
Method 8260D -TCLP:The method blank for preparation batch 280-695817 and analytical batch 280-695979 contained 2-
Butanone (MEK)and Tetrachloroethene above the method detection limit.This target analyte concentration was less than the
reporting limit (RL)in the method blank;therefore,re-extraction and/or re-analysis of samples was not performed.IDW-W-050725
(280-207337-1)and (LB3 280-695817/1-A)
Method 8260D -TCLP:Insufficient sample volume was available to perform a matrix spike/matrix spike duplicate (MS/MSD)
associated with preparation batch 280-695817 and analytical batch 280-695979.
No additional analytical or quality issues were noted,other than those described above or in the Definitions/Glossary page.
GC/MS Semi VOA
Method 8270E -TCLP:Internal Standard (ISTD)retention times for the following sample was outside the acceptance criteria of
+/-0.17 minutes from the mid-point of the initial calibration:(CCVIS 280-696235/3).The sample(s)were within +/-0.17 minutes
from the daily calibration verification;therefore,no corrective action was required per the laboratory's SOP.
Method 8270E -TCLP:Insufficient sample volume was available to perform a matrix spike/matrix spike duplicate (MS/MSD)
associated with preparation batch 280-695555 and 280-696212.LCS/LCSD was provided.
No additional analytical or quality issues were noted,other than those described above or in the Definitions/Glossary page.
Metals
Method 6010D -TCLP:The instrument blank for analytical batch 280-696041 contained Cd greater than one-half the reporting limit
(RL),and were not re-analyzed because sample results were either at least 10x greater than the instrument blank or non detect.
The data have been qualified and reported.
Method 6010D -TCLP:The method blank for preparation batch 280-695555 and 280-695643 contained Pb above the reporting
limit (RL).None of the samples associated with this method blank contained the target compound;therefore,re-extraction and/or
re-analysis of samples were not performed.
No additional analytical or quality issues were noted,other than those described above or in the Definitions/Glossary page.
Case Narrative
Client: AECOM Job ID: 280-207337-1
Project: Chevron 71887 - Little Ogden, UT
Eurofins Denver
Job ID: 280-207337-1 Eurofins Denver
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Detection Summary
Job ID: 280-207337-1Client: AECOM
Project/Site: Chevron 71887 - Little Ogden, UT
Client Sample ID: IDW-W-050725 Lab Sample ID: 280-207337-1
Benzene
RL
10 ug/L
MDL
2.5
Analyte Result Qualifier Unit Dil Fac D Method Prep Type
TCLP12008260D
2-Methylphenol 10 ug/L4.0 TCLP17.9 J 8270E
Total Cresols 10 ug/L4.0 TCLP17.9 J 8270E
Barium 100 ug/L25 TCLP112006010D
Eurofins Denver
This Detection Summary does not include radiochemical test results.
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Method Summary
Job ID: 280-207337-1Client: AECOM
Project/Site: Chevron 71887 - Little Ogden, UT
Method Method Description LaboratoryProtocol
SW8468260DVolatile Organic Compounds by GC/MS EET DEN
SW8468270ESemivolatile Organic Compounds (GC/MS)EET DEN
SW8466010DMetals (ICP)EET DEN
SW8467470AMercury (CVAA)EET DEN
SW8461311TCLP Extraction EET DEN
SW8463005APreparation, Total Recoverable or Dissolved Metals EET DEN
SW8463510CLiquid-Liquid Extraction (Separatory Funnel)EET DEN
SW8465030BPurge and Trap EET DEN
SW8467470APreparation, Mercury EET DEN
Protocol References:
SW846 = "Test Methods For Evaluating Solid Waste, Physical/Chemical Methods", Third Edition, November 1986 And Its Updates.
Laboratory References:
EET DEN = Eurofins Denver, 4955 Yarrow Street, Arvada, CO 80002, TEL [phone]
Eurofins Denver
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Sample Summary
Client: AECOM Job ID: 280-207337-1
Project/Site: Chevron 71887 - Little Ogden, UT
Lab Sample ID Client Sample ID Matrix Collected Received
280-207337-1 IDW-W-050725 Water 05/07/25 19:10 05/09/25 09:05
Eurofins Denver
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Client Sample Results
Job ID: 280-207337-1Client: AECOM
Project/Site: Chevron 71887 - Little Ogden, UT
Method: SW846 8260D - Volatile Organic Compounds by GC/MS - TCLP
Lab Sample ID: 280-207337-1Client Sample ID: IDW-W-050725
Matrix: WaterDate Collected: 05/07/25 19:10
Date Received: 05/09/25 09:05
RL MDL
200 10 2.5 ug/L 05/15/25 00:24 1
Analyte Dil FacAnalyzedPreparedUnitDResultQualifier
Benzene
100 40 ug/L 05/15/25 00:24 1ND2-Butanone (MEK)
10 2.5 ug/L 05/15/25 00:24 1NDCarbon tetrachloride
10 2.5 ug/L 05/15/25 00:24 1NDChlorobenzene
10 2.5 ug/L 05/15/25 00:24 1NDChloroform
10 2.5 ug/L 05/15/25 00:24 1ND1,2-Dichloroethane
10 2.5 ug/L 05/15/25 00:24 1ND1,1-Dichloroethene
10 2.5 ug/L 05/15/25 00:24 1NDTetrachloroethene
10 2.5 ug/L 05/15/25 00:24 1NDTrichloroethene
10 2.5 ug/L 05/15/25 00:24 1NDVinyl chloride
1,2-Dichloroethane-d4 (Surr)109 80 -120 05/15/25 00:24 1
Surrogate Dil FacAnalyzedPreparedQualifierLimits%Recovery
Toluene-d8 (Surr)99 05/15/25 00:24 180-120
4-Bromofluorobenzene (Surr)97 05/15/25 00:24 180-120
Dibromofluoromethane (Surr)102 05/15/25 00:24 180-120
Method: SW846 8270E - Semivolatile Organic Compounds (GC/MS) - TCLP
Lab Sample ID: 280-207337-1Client Sample ID: IDW-W-050725
Matrix: WaterDate Collected: 05/07/25 19:10
Date Received: 05/09/25 09:05
RL MDL
7.9 J 10 4.0 ug/L 05/15/25 15:38 05/16/25 16:07 1
Analyte Dil FacAnalyzedPreparedUnitDResultQualifier
2-Methylphenol
10 4.0 ug/L 05/15/25 15:38 05/16/25 16:07 1ND3 & 4 Methylphenol
10 4.0 ug/L 05/15/25 15:38 05/16/25 16:07 17.9 JTotal Cresols
4.0 1.0 ug/L 05/15/25 15:38 05/16/25 16:07 1ND1,4-Dichlorobenzene
10 4.0 ug/L 05/15/25 15:38 05/16/25 16:07 1ND2,4-Dinitrotoluene
10 4.0 ug/L 05/15/25 15:38 05/16/25 16:07 1NDHexachlorobenzene
10 4.0 ug/L 05/15/25 15:38 05/16/25 16:07 1NDHexachlorobutadiene
10 4.0 ug/L 05/15/25 15:38 05/16/25 16:07 1NDHexachloroethane
10 4.0 ug/L 05/15/25 15:38 05/16/25 16:07 1NDNitrobenzene
50 20 ug/L 05/15/25 15:38 05/16/25 16:07 1NDPentachlorophenol
50 20 ug/L 05/15/25 15:38 05/16/25 16:07 1NDPyridine
10 4.0 ug/L 05/15/25 15:38 05/16/25 16:07 1ND2,4,6-Trichlorophenol
10 4.0 ug/L 05/15/25 15:38 05/16/25 16:07 1ND2,4,5-Trichlorophenol
2-Fluorobiphenyl (Surr)77 39 -120 05/15/25 15:38 05/16/25 16:07 1
Surrogate Dil FacAnalyzedPreparedQualifierLimits%Recovery
2-Fluorophenol 52 05/15/25 15:38 05/16/25 16:07 124-120
Phenol-d5 31 05/15/25 15:38 05/16/25 16:07 118-120
2,4,6-Tribromophenol 105 05/15/25 15:38 05/16/25 16:07 163-133
Terphenyl-d14 97 05/15/25 15:38 05/16/25 16:07 166-128
Nitrobenzene-d5 83 05/15/25 15:38 05/16/25 16:07 146-120
Eurofins Denver
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Client Sample Results
Job ID: 280-207337-1Client: AECOM
Project/Site: Chevron 71887 - Little Ogden, UT
Method: SW846 6010D - Metals (ICP) - TCLP
Lab Sample ID: 280-207337-1Client Sample ID: IDW-W-050725
Matrix: WaterDate Collected: 05/07/25 19:10
Date Received: 05/09/25 09:05
RL MDL
ND 100 25 ug/L 05/13/25 15:24 05/15/25 00:06 1
Analyte Dil FacAnalyzedPreparedUnitDResultQualifier
Silver
150 50 ug/L 05/13/25 15:24 05/15/25 00:06 1NDArsenic
100 25 ug/L 05/13/25 15:24 05/15/25 00:06 11200Barium
10 2.5 ug/L 05/13/25 15:24 05/15/25 00:06 1NDCadmium
50 15 ug/L 05/13/25 15:24 05/15/25 00:06 1NDChromium
100 25 ug/L 05/13/25 15:24 05/15/25 00:06 1NDLead
200 50 ug/L 05/13/25 15:24 05/15/25 00:06 1NDSelenium
Method: SW846 7470A - Mercury (CVAA) - TCLP
Lab Sample ID: 280-207337-1Client Sample ID: IDW-W-050725
Matrix: WaterDate Collected: 05/07/25 19:10
Date Received: 05/09/25 09:05
RL MDL
ND 2.0 0.60 ug/L 05/13/25 10:17 05/13/25 15:33 1
Analyte Dil FacAnalyzedPreparedUnitDResultQualifier
Mercury
Eurofins Denver
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Surrogate Summary
Job ID: 280-207337-1Client: AECOM
Project/Site: Chevron 71887 - Little Ogden, UT
Method: 8260D - Volatile Organic Compounds by GC/MS
Prep Type: TCLPMatrix: Water
Lab Sample ID Client Sample ID (80-120)(80-120)(80-120)(80-120)
DCA TOL BFB DBFM
109 99 97 102280-207337-1
Percent Surrogate Recovery (Acceptance Limits)
IDW-W-050725
108 100 102 101LB3 280-695817/1-A Method Blank
102 99 100 102LCS 280-695817/2-A Lab Control Sample
103 98 99 101LCSD 280-695817/3-A Lab Control Sample Dup
Surrogate Legend
DCA = 1,2-Dichloroethane-d4 (Surr)
TOL = Toluene-d8 (Surr)
BFB = 4-Bromofluorobenzene (Surr)
DBFM = Dibromofluoromethane (Surr)
Method: 8270E - Semivolatile Organic Compounds (GC/MS)
Prep Type: TCLPMatrix: Water
Lab Sample ID Client Sample ID (39-120)(24-120)(18-120)(63-133)(66-128)(46-120)
FBP 2FP PHL TBP TPHL NBZ
77 52 31 105 97 83280-207337-1
Percent Surrogate Recovery (Acceptance Limits)
IDW-W-050725
71 55 34 9991 81LB3 280-695555/1-F Method Blank
79 58 36 101101 87LCS 280-695555/2-F Lab Control Sample
79 57 35 9796 85LCSD 280-695555/3-D Lab Control Sample Dup
Surrogate Legend
FBP = 2-Fluorobiphenyl (Surr)
2FP = 2-Fluorophenol
PHL = Phenol-d5
TBP = 2,4,6-Tribromophenol
TPHL = Terphenyl-d14
NBZ = Nitrobenzene-d5
Eurofins Denver
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QC Sample Results
Job ID: 280-207337-1Client: AECOM
Project/Site: Chevron 71887 - Little Ogden, UT
Method: 8260D - Volatile Organic Compounds by GC/MS
Client Sample ID: Method BlankLab Sample ID: LB3 280-695817/1-A
Matrix: Water Prep Type: TCLP
Analysis Batch: 695979
RL MDL
Benzene ND 10 2.5 ug/L 05/14/25 20:54 1
LB3 LB3
Analyte Dil FacAnalyzedPreparedDUnitResultQualifier
94.9 J 40100 ug/L 05/14/25 20:54 12-Butanone (MEK)
ND 2.510 ug/L 05/14/25 20:54 1Carbon tetrachloride
ND 2.510 ug/L 05/14/25 20:54 1Chlorobenzene
ND 2.510 ug/L 05/14/25 20:54 1Chloroform
ND 2.510 ug/L 05/14/25 20:54 11,2-Dichloroethane
ND 2.510 ug/L 05/14/25 20:54 11,1-Dichloroethene
3.63 J 2.510 ug/L 05/14/25 20:54 1Tetrachloroethene
ND 2.510 ug/L 05/14/25 20:54 1Trichloroethene
ND 2.510 ug/L 05/14/25 20:54 1Vinyl chloride
1,2-Dichloroethane-d4 (Surr)108 80 -120 05/14/25 20:54 1
LB3 LB3
Surrogate Dil FacPreparedAnalyzedQualifierLimits%Recovery
100 05/14/25 20:54 1Toluene-d8 (Surr)80 -120
102 05/14/25 20:54 14-Bromofluorobenzene (Surr)80 -120
101 05/14/25 20:54 1Dibromofluoromethane (Surr)80 -120
Client Sample ID: Lab Control SampleLab Sample ID: LCS 280-695817/2-A
Matrix: Water Prep Type: TCLP
Analysis Batch: 695979
Benzene 250 263 ug/L 105 80 -121
Analyte
LCS LCS
DUnitResultQualifier %Rec
Spike
Added
%Rec
Limits
2-Butanone (MEK)1000 1130 ug/L 113 59 -141
Carbon tetrachloride 250 283 ug/L 113 72 -131
Chlorobenzene 250 256 ug/L 102 80 -120
Chloroform 250 268 ug/L 107 80 -120
1,2-Dichloroethane 250 275 ug/L 110 73 -124
1,1-Dichloroethene 250 232 ug/L 93 76 -124
Tetrachloroethene 250 262 ug/L 105 79 -125
Trichloroethene 250 257 ug/L 103 79 -121
Vinyl chloride 250 284 ug/L 114 60 -136
1,2-Dichloroethane-d4 (Surr)80 -120
Surrogate
102
LCS LCS
Qualifier Limits%Recovery
99Toluene-d8 (Surr)80 -120
1004-Bromofluorobenzene (Surr)80 -120
102Dibromofluoromethane (Surr)80 -120
Client Sample ID: Lab Control Sample DupLab Sample ID: LCSD 280-695817/3-A
Matrix: Water Prep Type: TCLP
Analysis Batch: 695979
Benzene 250 267 ug/L 107 80 -121 2 20
Analyte
LCSD LCSD
DUnitResultQualifier %Rec
Spike
Added
%Rec
Limits LimitRPD
RPD
2-Butanone (MEK)1000 1180 ug/L 118 59 -141 4 20
Carbon tetrachloride 250 277 ug/L 111 72 -131 2 20
Chlorobenzene 250 268 ug/L 107 80 -120 5 20
Eurofins Denver
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QC Sample Results
Job ID: 280-207337-1Client: AECOM
Project/Site: Chevron 71887 - Little Ogden, UT
Method: 8260D - Volatile Organic Compounds by GC/MS (Continued)
Client Sample ID: Lab Control Sample DupLab Sample ID: LCSD 280-695817/3-A
Matrix: Water Prep Type: TCLP
Analysis Batch: 695979
Chloroform 250 279 ug/L 112 80 -120 4 20
Analyte
LCSD LCSD
DUnitResultQualifier %Rec
Spike
Added
%Rec
Limits LimitRPD
RPD
1,2-Dichloroethane 250 290 ug/L 116 73 -124 5 20
1,1-Dichloroethene 250 229 ug/L 92 76 -124 1 20
Tetrachloroethene 250 268 ug/L 107 79 -125 2 20
Trichloroethene 250 263 ug/L 105 79 -121 2 20
Vinyl chloride 250 284 ug/L 114 60 -136 0 23
1,2-Dichloroethane-d4 (Surr)80 -120
Surrogate
103
LCSD LCSD
Qualifier Limits%Recovery
98Toluene-d8 (Surr)80 -120
994-Bromofluorobenzene (Surr)80 -120
101Dibromofluoromethane (Surr)80 -120
Method: 8270E - Semivolatile Organic Compounds (GC/MS)
Client Sample ID: Method BlankLab Sample ID: LB3 280-695555/1-F
Matrix: Water Prep Type: TCLP
Analysis Batch: 696235 Prep Batch: 696212
RL MDL
2-Methylphenol ND 10 4.0 ug/L 05/15/25 15:38 05/16/25 13:37 1
LB3 LB3
Analyte Dil FacAnalyzedPreparedDUnitResultQualifier
ND 4.010 ug/L 05/15/25 15:38 05/16/25 13:37 13 & 4 Methylphenol
ND 4.010 ug/L 05/15/25 15:38 05/16/25 13:37 1Total Cresols
ND 1.04.0 ug/L 05/15/25 15:38 05/16/25 13:37 11,4-Dichlorobenzene
ND 4.010 ug/L 05/15/25 15:38 05/16/25 13:37 12,4-Dinitrotoluene
ND 4.010 ug/L 05/15/25 15:38 05/16/25 13:37 1Hexachlorobenzene
ND 4.010 ug/L 05/15/25 15:38 05/16/25 13:37 1Hexachlorobutadiene
ND 4.010 ug/L 05/15/25 15:38 05/16/25 13:37 1Hexachloroethane
ND 4.010 ug/L 05/15/25 15:38 05/16/25 13:37 1Nitrobenzene
ND 2050 ug/L 05/15/25 15:38 05/16/25 13:37 1Pentachlorophenol
ND 2050 ug/L 05/15/25 15:38 05/16/25 13:37 1Pyridine
ND 4.010 ug/L 05/15/25 15:38 05/16/25 13:37 12,4,6-Trichlorophenol
ND 4.010 ug/L 05/15/25 15:38 05/16/25 13:37 12,4,5-Trichlorophenol
2-Fluorobiphenyl (Surr)71 39 -120 05/16/25 13:37 1
LB3 LB3
Surrogate
05/15/25 15:38
Dil FacPreparedAnalyzedQualifierLimits%Recovery
55 05/15/25 15:38 05/16/25 13:37 12-Fluorophenol 24 -120
34 05/15/25 15:38 05/16/25 13:37 1Phenol-d5 18 -120
91 05/15/25 15:38 05/16/25 13:37 12,4,6-Tribromophenol 63 -133
99 05/15/25 15:38 05/16/25 13:37 1Terphenyl-d14 66 -128
81 05/15/25 15:38 05/16/25 13:37 1Nitrobenzene-d5 46 -120
Client Sample ID: Lab Control SampleLab Sample ID: LCS 280-695555/2-F
Matrix: Water Prep Type: TCLP
Analysis Batch: 696235 Prep Batch: 696212
2-Methylphenol 80.0 63.7 ug/L 80 39 -120
Analyte
LCS LCS
DUnitResultQualifier %Rec
Spike
Added
%Rec
Limits
Eurofins Denver
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QC Sample Results
Job ID: 280-207337-1Client: AECOM
Project/Site: Chevron 71887 - Little Ogden, UT
Method: 8270E - Semivolatile Organic Compounds (GC/MS) (Continued)
Client Sample ID: Lab Control SampleLab Sample ID: LCS 280-695555/2-F
Matrix: Water Prep Type: TCLP
Analysis Batch: 696235 Prep Batch: 696212
3 & 4 Methylphenol 80.0 62.0 ug/L 78 37 -120
Analyte
LCS LCS
DUnitResultQualifier %Rec
Spike
Added
%Rec
Limits
1,4-Dichlorobenzene 80.0 40.3 ug/L 50 10 -120
2,4-Dinitrotoluene 80.0 90.7 ug/L 113 67 -122
Hexachlorobenzene 80.0 77.2 ug/L 96 61 -120
Hexachlorobutadiene 80.0 36.2 ug/L 45 10 -120
Hexachloroethane 80.0 37.2 ug/L 47 10 -120
Nitrobenzene 80.0 68.4 ug/L 86 38 -120
Pentachlorophenol 160 141 ug/L 88 48 -140
Pyridine 160 21.4 J ug/L 13 10 -120
2,4,6-Trichlorophenol 80.0 79.7 ug/L 100 53 -122
2,4,5-Trichlorophenol 80.0 78.9 ug/L 99 57 -121
2-Fluorobiphenyl (Surr)39 -120
Surrogate
79
LCS LCS
Qualifier Limits%Recovery
582-Fluorophenol 24 -120
36Phenol-d5 18 -120
1012,4,6-Tribromophenol 63 -133
101Terphenyl-d14 66 -128
87Nitrobenzene-d5 46 -120
Client Sample ID: Lab Control Sample DupLab Sample ID: LCSD 280-695555/3-D
Matrix: Water Prep Type: TCLP
Analysis Batch: 696235 Prep Batch: 696212
2-Methylphenol 80.0 59.1 ug/L 74 39 -120 8 33
Analyte
LCSD LCSD
DUnitResultQualifier %Rec
Spike
Added
%Rec
Limits LimitRPD
RPD
3 & 4 Methylphenol 80.0 56.8 ug/L 71 37 -120 9 33
1,4-Dichlorobenzene 80.0 43.0 ug/L 54 10 -120 7 70
2,4-Dinitrotoluene 80.0 87.0 ug/L 109 67 -122 4 30
Hexachlorobenzene 80.0 73.7 ug/L 92 61 -120 5 30
Hexachlorobutadiene 80.0 43.3 ug/L 54 10 -120 18 94
Hexachloroethane 80.0 40.2 ug/L 50 10 -120 8 88
Nitrobenzene 80.0 64.9 ug/L 81 38 -120 5 32
Pentachlorophenol 160 123 ug/L 77 48 -140 13 30
Pyridine 160 ND ug/L 12 10 -120 8 100
2,4,6-Trichlorophenol 80.0 75.6 ug/L 95 53 -122 5 30
2,4,5-Trichlorophenol 80.0 76.6 ug/L 96 57 -121 3 30
2-Fluorobiphenyl (Surr)39 -120
Surrogate
79
LCSD LCSD
Qualifier Limits%Recovery
572-Fluorophenol 24 -120
35Phenol-d5 18 -120
962,4,6-Tribromophenol 63 -133
97Terphenyl-d14 66 -128
85Nitrobenzene-d5 46 -120
Eurofins Denver
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QC Sample Results
Job ID: 280-207337-1Client: AECOM
Project/Site: Chevron 71887 - Little Ogden, UT
Method: 6010D - Metals (ICP)
Client Sample ID: Method BlankLab Sample ID: LB3 280-695555/1-C
Matrix: Water Prep Type: TCLP
Analysis Batch: 696041 Prep Batch: 695643
RL MDL
Silver ND 100 25 ug/L 05/13/25 15:24 05/14/25 23:08 1
LB3 LB3
Analyte Dil FacAnalyzedPreparedDUnitResultQualifier
ND 50150 ug/L 05/13/25 15:24 05/14/25 23:08 1Arsenic
ND 25100 ug/L 05/13/25 15:24 05/14/25 23:08 1Barium
ND 2.510 ug/L 05/13/25 15:24 05/14/25 23:08 1Cadmium
ND 1550 ug/L 05/13/25 15:24 05/14/25 23:08 1Chromium
353 25100 ug/L 05/13/25 15:24 05/14/25 23:08 1Lead
ND 50200 ug/L 05/13/25 15:24 05/14/25 23:08 1Selenium
Client Sample ID: Lab Control SampleLab Sample ID: LCS 280-695555/2-C
Matrix: Water Prep Type: TCLP
Analysis Batch: 696041 Prep Batch: 695643
Silver 1250 1340 ug/L 107 85 -115
Analyte
LCS LCS
DUnitResultQualifier %Rec
Spike
Added
%Rec
Limits
Arsenic 8000 8430 ug/L 105 85 -115
Barium 15000 15900 ug/L 106 85 -115
Cadmium 6000 5900 ug/L 98 85 -115
Chromium 10000 9940 ug/L 99 85 -115
Lead 10000 10400 ug/L 104 85 -115
Selenium 6000 6260 ug/L 104 85 -115
Method: 7470A - Mercury (CVAA)
Client Sample ID: Method BlankLab Sample ID: LB3 280-695555/1-B
Matrix: Water Prep Type: TCLP
Analysis Batch: 695956 Prep Batch: 695592
RL MDL
Mercury ND 2.0 0.60 ug/L 05/13/25 10:17 05/13/25 15:12 1
LB3 LB3
Analyte Dil FacAnalyzedPreparedDUnitResultQualifier
Client Sample ID: Lab Control SampleLab Sample ID: LCS 280-695555/2-B
Matrix: Water Prep Type: TCLP
Analysis Batch: 695956 Prep Batch: 695592
Mercury 5.00 4.90 ug/L 98 85 -115
Analyte
LCS LCS
DUnitResultQualifier %Rec
Spike
Added
%Rec
Limits
Client Sample ID: Lab Control Sample DupLab Sample ID: LCSD 280-695555/3-B
Matrix: Water Prep Type: TCLP
Analysis Batch: 695956 Prep Batch: 695592
Mercury 5.00 4.82 ug/L 96 85 -115 2 20
Analyte
LCSD LCSD
DUnitResultQualifier %Rec
Spike
Added
%Rec
Limits LimitRPD
RPD
Eurofins Denver
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QC Association Summary
Job ID: 280-207337-1Client: AECOM
Project/Site: Chevron 71887 - Little Ogden, UT
GC/MS VOA
Leach Batch: 695817
Lab Sample ID Client Sample ID Prep Type Matrix Method Prep Batch
Water 1311280-207337-1 IDW-W-050725 TCLP
Water 1311LB3 280-695817/1-A Method Blank TCLP
Water 1311LCS 280-695817/2-A Lab Control Sample TCLP
Water 1311LCSD 280-695817/3-A Lab Control Sample Dup TCLP
Analysis Batch: 695979
Lab Sample ID Client Sample ID Prep Type Matrix Method Prep Batch
Water 8260D 695817280-207337-1 IDW-W-050725 TCLP
Water 8260D 695817LB3 280-695817/1-A Method Blank TCLP
Water 8260D 695817LCS 280-695817/2-A Lab Control Sample TCLP
Water 8260D 695817LCSD 280-695817/3-A Lab Control Sample Dup TCLP
GC/MS Semi VOA
Leach Batch: 695555
Lab Sample ID Client Sample ID Prep Type Matrix Method Prep Batch
Water 1311280-207337-1 IDW-W-050725 TCLP
Water 1311LB3 280-695555/1-F Method Blank TCLP
Water 1311LCS 280-695555/2-F Lab Control Sample TCLP
Water 1311LCSD 280-695555/3-D Lab Control Sample Dup TCLP
Prep Batch: 696212
Lab Sample ID Client Sample ID Prep Type Matrix Method Prep Batch
Water 3510C 695555280-207337-1 IDW-W-050725 TCLP
Water 3510C 695555LB3 280-695555/1-F Method Blank TCLP
Water 3510C 695555LCS 280-695555/2-F Lab Control Sample TCLP
Water 3510C 695555LCSD 280-695555/3-D Lab Control Sample Dup TCLP
Analysis Batch: 696235
Lab Sample ID Client Sample ID Prep Type Matrix Method Prep Batch
Water 8270E 696212280-207337-1 IDW-W-050725 TCLP
Water 8270E 696212LB3 280-695555/1-F Method Blank TCLP
Water 8270E 696212LCS 280-695555/2-F Lab Control Sample TCLP
Water 8270E 696212LCSD 280-695555/3-D Lab Control Sample Dup TCLP
Metals
Leach Batch: 695555
Lab Sample ID Client Sample ID Prep Type Matrix Method Prep Batch
Water 1311280-207337-1 IDW-W-050725 TCLP
Water 1311LB3 280-695555/1-B Method Blank TCLP
Water 1311LB3 280-695555/1-C Method Blank TCLP
Water 1311LCS 280-695555/2-B Lab Control Sample TCLP
Water 1311LCS 280-695555/2-C Lab Control Sample TCLP
Water 1311LCSD 280-695555/3-B Lab Control Sample Dup TCLP
Prep Batch: 695592
Lab Sample ID Client Sample ID Prep Type Matrix Method Prep Batch
Water 7470A 695555280-207337-1 IDW-W-050725 TCLP
Water 7470A 695555LB3 280-695555/1-B Method Blank TCLP
Water 7470A 695555LCS 280-695555/2-B Lab Control Sample TCLP
Water 7470A 695555LCSD 280-695555/3-B Lab Control Sample Dup TCLP
Eurofins Denver
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QC Association Summary
Job ID: 280-207337-1Client: AECOM
Project/Site: Chevron 71887 - Little Ogden, UT
Metals
Prep Batch: 695643
Lab Sample ID Client Sample ID Prep Type Matrix Method Prep Batch
Water 3005A 695555280-207337-1 IDW-W-050725 TCLP
Water 3005A 695555LB3 280-695555/1-C Method Blank TCLP
Water 3005A 695555LCS 280-695555/2-C Lab Control Sample TCLP
Analysis Batch: 695956
Lab Sample ID Client Sample ID Prep Type Matrix Method Prep Batch
Water 7470A 695592280-207337-1 IDW-W-050725 TCLP
Water 7470A 695592LB3 280-695555/1-B Method Blank TCLP
Water 7470A 695592LCS 280-695555/2-B Lab Control Sample TCLP
Water 7470A 695592LCSD 280-695555/3-B Lab Control Sample Dup TCLP
Analysis Batch: 696041
Lab Sample ID Client Sample ID Prep Type Matrix Method Prep Batch
Water 6010D 695643280-207337-1 IDW-W-050725 TCLP
Water 6010D 695643LB3 280-695555/1-C Method Blank TCLP
Water 6010D 695643LCS 280-695555/2-C Lab Control Sample TCLP
Eurofins Denver
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Lab Chronicle
Client: AECOM Job ID: 280-207337-1
Project/Site: Chevron 71887 - Little Ogden, UT
Client Sample ID: IDW-W-050725 Lab Sample ID: 280-207337-1
Matrix: WaterDate Collected: 05/07/25 19:10
Date Received: 05/09/25 09:05
Leach 1311 JPG05/14/25 09:29 EET DEN695817
Type
Batch
Method
Batch
Prep Type LabAnalystRun
Prepared
or Analyzed
Initial
Amount Amount
Final Batch
NumberFactor
Dil
TCLP 160 mL 160 mL
Completed:05/14/25 13:48 ¹
Analysis 8260D 1 695979 05/15/25 00:24 ETB EET DENTCLP0.5 mL 5 mL
Leach 1311 695555 05/12/25 14:03 DCL EET DENTCLP2000 mL 2000 mL
Completed:05/12/25 16:34 ¹
Prep 3510C 696212 05/15/25 15:38 JES EET DENTCLP250 mL 1 mL
Analysis 8270E 1 696235 05/16/25 16:07 MAB EET DENTCLP0 mL 1.0 mL
Leach 1311 695555 05/12/25 14:03 DCL EET DENTCLP2000 mL 2000 mL
Completed:05/12/25 16:34 ¹
Prep 3005A 695643 05/13/25 15:24 SLH EET DENTCLP10 mL 50 mL
Analysis 6010D 1 696041 05/15/25 00:06 NKC EET DENTCLP
Leach 1311 695555 05/12/25 14:03 DCL EET DENTCLP2000 mL 2000 mL
Completed:05/12/25 16:34 ¹
Prep 7470A 695592 05/13/25 10:17 AES EET DENTCLP30 mL 50 mL
Analysis 7470A 1 695956 05/13/25 15:33 AES EET DENTCLP
¹ This procedure uses a method stipulated length of time for the process. Both start and end times are displayed.
Laboratory References:
EET DEN = Eurofins Denver, 4955 Yarrow Street, Arvada, CO 80002, TEL [phone]
Eurofins Denver
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Accreditation/Certification Summary
Client: AECOM Job ID: 280-207337-1
Project/Site: Chevron 71887 - Little Ogden, UT
Laboratory: Eurofins Denver
The accreditations/certifications listed below are applicable to this report.
Authority Program Identification Number Expiration Date
Utah NELAP CO00026 07-31-25
Eurofins Denver
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Login Sample Receipt Checklist
Client: AECOM Job Number: 280-207337-1
Login Number: 207337
Question Answer Comment
Creator: Swegle, Jarod M
List Source: Eurofins Denver
List Number: 1
TrueRadioactivity wasn't checked or is </= background as measured by a survey
meter.
TrueThe cooler's custody seal, if present, is intact.
TrueSample custody seals, if present, are intact.
TrueThe cooler or samples do not appear to have been compromised or
tampered with.
TrueSamples were received on ice.
TrueCooler Temperature is acceptable.
TrueCooler Temperature is recorded.
TrueCOC is present.
TrueCOC is filled out in ink and legible.
TrueCOC is filled out with all pertinent information.
TrueIs the Field Sampler's name present on COC?
TrueThere are no discrepancies between the containers received and the COC.
TrueSamples are received within Holding Time (excluding tests with immediate
HTs)
TrueSample containers have legible labels.
TrueContainers are not broken or leaking.
TrueSample collection date/times are provided.
TrueAppropriate sample containers are used.
TrueSample bottles are completely filled.
N/ASample Preservation Verified.
TrueThere is sufficient vol. for all requested analyses, incl. any requested
MS/MSDs
TrueContainers requiring zero headspace have no headspace or bubble is
<6mm (1/4").
TrueMultiphasic samples are not present.
TrueSamples do not require splitting or compositing.
N/AResidual Chlorine Checked.
Eurofins Denver
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