DERR-2025-000386

COVER PAGE
December 2024 Groundwater
Monitoring Report
Former Blanding Chevron
200 North Highway 191 Blanding, Utah
Facility ID #5000247 Release ID GFB
January 10, 2025 | Terracon Project No. AL067004
Prepared for:
Utah Department of Environmental Quality
Salt Lake City, Utah
6952 South High Tech Dr. Ste. B
Midvale, Utah 84047
P [phone]
Terracon.com
Facilities | Environmental | Geotechnical | Materials i
COVER LETTER
January 10, 2025
Utah Department of Environmental Quality
Division of Environmental Response and Remediation
195 North 1950 West
Salt Lake City, Utah 84114
Attn: Mr. Mark Crim
E:[e-mail]
Re:December 2024 Groundwater Monitoring Report
Former Blanding Chevron
200 North Highway 191
Blanding, Utah
Facility ID #5000247 Release ID GFB
Terracon Project No. AL067004
Dear Mr. Crim:
Terracon Consultants, Inc. (Terracon) is pleased to submit this December 2024
Groundwater Monitoring Report documenting a groundwater sampling event conducted at
the former Blanding Chevron facility, located at 200 North Highway 191, Blanding, Utah.
Terracon performed this work pursuant to the approved Work Assignment No. GFB-36-
TER. This work was conducted under Terracon's contract (Contract Number 216383) with
the Division of Environmental Response and Remediation (DERR).
We appreciate the opportunity to have performed these services for you. Please contact
our office at [phone] if you have questions regarding this information or if we
can provide any other services.
Sincerely,
Terracon Consultants, Inc.
Andrew Turner Craig D. Eaton
Senior Project Manager Authorized Project Reviewer
Certified UST Consultant #CC0167
Facilities | Environmental | Geotechnical | Materials ii
Table of Contents
1.0 Introduction ................................................................................ 1
1.1 Site Description ..................................................................................... 1
1.2 Project Background ................................................................................ 1
1.3 Scope of Work ....................................................................................... 2
1.4 Standard of Care .................................................................................... 2
1.5 Additional Scope Limitations .................................................................... 2
1.6 Reliance ................................................................................................ 3
2.0 December 2024 Groundwater Sampling Event ................................. 3
3.0 Laboratory Analytical Methods ....................................................... 4
4.0 Data Evaluation ........................................................................... 5
4.1 Observations ......................................................................................... 5
4.2 Groundwater Sample Results ................................................................... 5
4.3 Quality Control ....................................................................................... 6
5.0 Findings and Conclusions .............................................................. 6
Appendices
Appendix A Exhibits
Exhibit 1:Topographic Map
Exhibit 2:Site Map
Exhibit 3:Shallow Aquifer Potentiometric Surface Map, December 2024
Exhibit 4:Deep Aquifer Potentiometric Surface Map, December 2024
Appendix B Groundwater Data Tables 1 & 2
Appendix C Chain of Custody and Laboratory Data Sheets
December 2024 Groundwater Monitoring Report
Former Blanding Chevron | Blanding, Utah
January 10, 2025 | Terracon Project No. AL067004
Facilities | Environmental | Geotechnical | Materials 1
1.0 Introduction
1.1 Site Description
The former Blanding Chevron facility is located at 200 North Highway 191, Blanding,Utah.
The site is assigned Facility ID 5000247, Release Site GFB by the Utah Division of
Environmental Response and Remediation (DERR).
Appendix A (Exhibit 1) presents a topographical map of the area.Exhibit 2 is a site diagram
depicting monitoring well locations.Exhibits 3 and 4 depict groundwater elevation contours
in the shallow and deep aquifers, respectively, based on depth-to-groundwater
measurements that were collected on December 17 and 18, 2024.
1.2 Project Background
The December 2024 monitoring event was conducted to evaluate the current state of
petroleum impacts to groundwater at the site. In particular, evaluation of petroleum
constituent concentrations remaining in the monitoring wells and assessment of light non-
aqueous phase liquid (LNAPL) remaining in some of the wells. These current evaluation and
assessment activities are predicated on several previous monitoring events and two dual-
phase (liquid and vapor) extraction events conducted at the site in January 2008 and
August 2008. During the extraction events, Durham Geo SoakEase product-selective
absorbent socks and stainless steel canisters were also installed at monitoring wells MW-3,
MW-5, and MW-6. Monitoring well MW-6 was damaged during subsequent site construction
and is no longer in service. Groundwater monitoring was recommended on an 18-month
schedule to observe LNAPL and the dissolved-phase contamination in the groundwater over
time.
In general, petroleum hydrocarbon concentrations have been relatively high, particularly
near the former underground storage tank (UST) basin (Appendix A Exhibit 2). Measurable
LNAPL has been persistent in the deep monitoring wells MW-3, MW-5, and MW-7 since the
September 2016 monitoring event as documented during the May 2018, October 2019,
September 2024, and December 2024 monitoring events. LNAPL was observed in MW-3B in
October 2019, September 2024, and December 2024 groundwater monitoring events.
LNAPL was also observed for the first time in MW-8 in the September 2024 event with a
measured thickness of approximately 1.65 feet, and LNAPL was present again in December
2024 with a measured thickness of 0.98 feet. Although no LNAPL was present in shallow
monitoring well MW-4B, dissolved petroleum constituents concentrations remain elevated.
December 2024 Groundwater Monitoring Report
Former Blanding Chevron | Blanding, Utah
January 10, 2025 | Terracon Project No. AL067004
Facilities | Environmental | Geotechnical | Materials 2
1.3 Scope of Work
The objective of Work Assignment GFB-36-TER was to measure depth to groundwater and
product thickness (where present) in all currently existing groundwater monitoring wells
(shallow wells MW-3B, MW-4B, and MW-8B, and deep wells MW-3, MW-4, MW-5, MW-7,
MW-8, and MW-10) using a product-water interface probe. The work plan for this
monitoring event also identified potential sampling of shallow monitoring wells MW-3B, MW-
4B and MW-8B, and deep monitoring wells MW-3, MW-4, MW-5, MW-7, MW-8 and MW-10.
However, MW-3, MW-3B, MW-5, MW 7, and MW-8 contained LNAPL and were not sampled.
Collection of a sample from the Blanding City public access well from the publicly accessed
spigot was also conducted for use as a baseline reading (field blank) as per previous events.
As part of this work plan, absorbent socks in monitoring wells MW-3, MW-3B, MW-5, MW-7,
and MW-8 were changed out and replaced with new ones.
The remainder of this report documents the results of this groundwater monitoring event
completed pursuant the work plan to conduct quarterly monitoring at the site (i.e.,
approximately September 2024, December 2024, March 2025, and June 2025).
1.4 Standard of Care
Terracon’s services were performed in a manner consistent with generally accepted
practices of the profession undertaken in similar studies in the same geographical area
during the same time period. Please note that Terracon does not warrant the work of
laboratories, regulatory agencies or other third parties supplying information used in the
preparation of the report. These services were performed in accordance with the scope of
work agreed with you, our client, as reflected in our proposal, and were not restricted by
ASTM E1903-19.
1.5 Additional Scope Limitations
Findings, conclusions, and recommendations resulting from these services are based upon
information derived from the on-site activities and other services performed under this
scope of work. Such information is subject to change over time. Certain indicators of the
presence of hazardous substances, petroleum products, or other constituents may have
been latent, inaccessible, unobservable, non-detectable or not present during these
services, and we cannot represent that the site contains no hazardous substances, toxic
materials, petroleum products, or other latent conditions beyond those identified during this
investigation. Subsurface conditions may vary from those encountered at specific borings or
wells or during other surveys, tests, assessments, investigations or exploratory services;
the data, interpretations, findings, and our recommendations are based solely upon data
obtained at the time and within the scope of these services.
December 2024 Groundwater Monitoring Report
Former Blanding Chevron | Blanding, Utah
January 10, 2025 | Terracon Project No. AL067004
Facilities | Environmental | Geotechnical | Materials 3
1.6 Reliance
This report has been prepared for the exclusive use and reliance of the Utah Department of
Environmental Quality (UDEQ). Use or reliance by any other party is prohibited without the
written authorization of the UDEQ and Terracon. Reliance on the report by the client and all
authorized parties will be subject to the terms, conditions and limitations stated in the
proposal, report, and Terracon’s Terms and Conditions. The limitation of liability defined in
the Terms and Conditions is the aggregate limit of Terracon’s liability to the client and all
relying parties.
2.0 December 2024 Groundwater Sampling Event
On December 17 and 18, 2024, Terracon measured free product thickness, where present,
and depth to groundwater in the groundwater monitoring wells (shallow wells MW-3B, MW-
4B, and MW-8B, and deep wells MW-3, MW-4, MW-5, MW-7, MW-8, and MW-10) using a
decontaminated product-water interface probe. Groundwater gradients were calculated for
the shallow and deep aquifers. Where free product was measured, the groundwater
elevations were corrected using the following formula.
Corrected GW Elev. (ft/bgs) = Measured GW Elev. (ft/bgs) + (LNAPL Thickness ft x 0.73)
Where:
Corrected GW Elev. is the corrected groundwater elevation taking LNAPL into
account in feet below the ground surface (bgs).
Measured GW Elev. is the measured groundwater elevation in feet bgs.
LNAPL Thickness is the measured thickness of LNAPL in feet.
0.73 is the relative density of automobile gasoline LNAPL.
As LNAPL was observed in deep wells MW-3, MW-5, MW-7 and MW-8 and shallow well MW-
3B during the December 2024 monitoring event, groundwater samples were not collected at
these locations. Groundwater samples for MW-4, MW-4B, MW-8B, and MW-10 were
collected on December 17, 2024, and the Blanding City public access well (Blanding
Municipal Well or BMW) was sampled on December 18, 2024.
Groundwater sampling was conducted by a Utah-certified UST Groundwater and Soil
Sampler (John R. Murphy GS 1947), with oversight from Utah-certified UST Consultants
(Amy Austin; CC0238 and Craig Eaton; CC0167).
Prior to sampling, three casing volumes were purged from the selected monitoring wells
using a disposable bailer. Following the removal of three casing volumes at each of the
wells, a disposable bailer was again used to collect the groundwater sample. The total
volume of water purged from each of the monitoring wells sampled was approximately 6
gallons from MW-4, 4 gallons from MW-8B, and 10 gallons from MW-10. MW-4B became dry
December 2024 Groundwater Monitoring Report
Former Blanding Chevron | Blanding, Utah
January 10, 2025 | Terracon Project No. AL067004
Facilities | Environmental | Geotechnical | Materials 4
after bailing 15 gallons of the calculated 26 gallons. After 20 minutes, recharge was
sufficient for groundwater sample collection.
All purge water was surface applied near the well that generated the water and allowed to
evaporate or infiltrate into surface soils. Care was taken to not allow purge water to affect
nearby receptors (storm water catch basins, other monitoring wells, utilities, etc.) or
residential property.
A sample was also collected from the nearby Blanding City public access well. Additionally, a
trip blank was also kept with the sample cooler during this event and submitted for
laboratory analyses.
3.0 Laboratory Analytical Methods
Groundwater samples were collected and placed in laboratory-prepared containers, labeled,
and placed on ice in a cooler and transported to Chemtech-Ford Laboratories, a Utah-
certified analytical laboratory located in Salt Lake City, Utah.
The four groundwater samples and field blank sample (Blanding Municipal Well) were
submitted for analyses of methyl tertiary-butyl ether, benzene, toluene, ethylbenzene, total
xylenes, and naphthalene (MBTEXN), gasoline-range total petroleum hydrocarbons (TPH-
GRO), and diesel-range total petroleum hydrocarbons (TPH-DRO) with silica gel treatment
(SGT). The trip blank was analyzed for MBTEXN and TPH-GRO.
The samples were analyzed using the following methods:
Analysis Sample Type No. of
Samples Laboratory Method
MBTEXN and TPH-GRO
Groundwater,
Trip Blank, and
Field Blank
6 EPA Method 8260D
TPH-DRO (SGT)Groundwater and
Field Blank 5 EPA Method 8015C SGT
The executed chain-of-custody form and laboratory data sheets are provided in Appendix C.
December 2024 Groundwater Monitoring Report
Former Blanding Chevron | Blanding, Utah
January 10, 2025 | Terracon Project No. AL067004
Facilities | Environmental | Geotechnical | Materials 5
4.0 Data Evaluation
Please refer to Table 1 (Appendix B) for a summary of well construction details and current
and historical groundwater elevation data. Refer to Table 2 (Appendix B) for the current
and historical groundwater sample results, which also includes the Initial Screening Levels
(ISLs) and the Tier 1 Screening Criteria established by the DERR for comparison.
4.1 Observations
Depth-to-water measurements and groundwater elevations are presented in Table 1
(Appendix B). Depth-to-water in the shallow aquifer at the site was measured to range
between 6.84 to 8.39 feet below ground surface (bgs), which ranged from 0.76 to 1.74 feet
deeper than the September 2024 sampling event. Depth-to-water in the deeper aquifer was
measured to range between 72.37 to 80.36 feet bgs, which was generally consistent with
the September 2024 sampling event except for monitoring well MW-5 where depth-to-water
was 0.67 feet deeper than the September 2024 sampling event. LNAPL was observed in
deep wells MW-3 (2.88 feet thick), MW-5 (2.93 feet thick), MW-7 (1.52 feet thick), and MW-
8 (0.98 feet thick). LNAPL was also observed in shallow well MW-3B (0.04 feet thick).
Groundwater gradients in the shallow and deep aquifers are displayed on Exhibits 3 and 4
(Appendix A), respectively. Where free product was measured, the groundwater gradients
were calculated using the corrected groundwater elevations, as discussed in Section 2.0.
The general groundwater flow direction is towards the south-southeast in the shallow
aquifer and to the south-southeast in the deep aquifer, which is in general agreement with
previous monitoring events.
4.2 Groundwater Sample Results
The analytical results are tabulated in Table 2 (Appendix B). Analytical results of the
monitoring well samples indicate that no petroleum constituent concentrations were present
above laboratory reporting limits in monitoring wells MW-8B or MW-10. TPH-GRO and TPH-
DRO were reported in deep well MW-4 at 1,660 µg/L and 1,700 µg/L, respectively, which
exceeded their ISLs but were below their Tier 1 criteria. Benzene was reported at 779 µg/L
in deep well MW-4, which exceeded both its ISL and Tier 1 criteria. Shallow monitoring well
MW-4B results reported TPH-DRO (3,800 µg/L), toluene (1,100 µg/L), and ethylbenzene
(987 µg/L) exceeding their ISLs, and TPH-GRO (10,300 µg/L) and benzene (1,003 µg/L)
exceeding their Tier 1 criteria. None of the petroleum constituents analyzed were reported
above the analytical method reporting limits in shallow monitoring well MW-8B, deep
monitoring well MW-10, or the field blank from the Blanding Municipal Well. No samples
were collected from monitoring wells MW-3, MW-3B, MW-5, MW-7 or MW-8 due to the
presence of LNAPL.
December 2024 Groundwater Monitoring Report
Former Blanding Chevron | Blanding, Utah
January 10, 2025 | Terracon Project No. AL067004
Facilities | Environmental | Geotechnical | Materials 6
4.3 Quality Control
Quality control for the sampling program was provided by using standardized sample
collection and handling methods, collecting and analyzing a trip blank and field blank
(Blanding City well), documenting pertinent field information, and keeping chain-of-custody
records, as well as using a Utah-certified laboratory. All sampling procedures followed
Terracon’s SOPs.
The analytical laboratory report indicated that samples were extracted and analyzed within
appropriate sample holding times. Internal laboratory QA/QC procedures and results are
presented in the laboratory report, and these results were within acceptable limits set by
the laboratory.
None of the compounds analyzed were reported above their respective laboratory reporting
limits in either the trip blank or the field blank.
5.0 Findings and Conclusions
An LNAPL plume was observed in the deep and shallow aquifers, as indicated by the
presence of free product in deep wells MW-3, MW-5, MW-7 and MW-8, and shallow well
MW-3B. LNAPL thicknesses in MW-3B (0.04 feet thick), MW-7 (1.52 feet thick), and MW-8
(0.98 feet thick) were less than the previous measurements from the September 2024
event. However, product thicknesses in wells MW-3 (2.88 feet thick) and MW-5 (2.93 feet
thick) were greater than the previous sampling event. All product thickness measurements
are tabulated on Table 1 (Appendix B).
The groundwater elevations in the deeper aquifer have remained relatively stable since the
last monitoring event in September 2024. Shallow wells have seen a decrease in
groundwater elevation with MW-3B (0.75 feet lower), MW-4B (1.24 feet lower) and MW-8B
(0.75 feet lower). Historically, groundwater elevations in deep monitoring wells (MW-3, -4, -
5, -7, and -8) have dropped at least 18 feet since 1998. It is possible that the drop in
groundwater elevation is affecting the amount and distribution of LNAPL that is present in
several of these deep aquifer wells.
Petroleum hydrocarbon impacts to the shallow aquifer appear to be relatively stable over
time. Historically MW-3B had an inconsistent layer of LNAPL since 1999. However, even
when LNAPL has not been present, concentrations of TPH-GRO, TPH-DRO, benzene, toluene,
and ethylbenzene have exceeded ISLs and Tier 1 screening criteria. Analytical results from
monitoring well MW-4B indicate groundwater also exhibited historically similar petroleum
constituent concentrations, with benzene (1,003 µg/L) exceeding Tier 1 screening levels,
and TPH-DRO (3,800 µg/L) and ethylbenzene (987 µg/L) exceeding ISLs. While TPH-GRO
(10,300 µg/L) did exceed Tier 1 screening levels, levels have generally trended downward
since 2007. Analysis of groundwater from shallow monitoring well MW-8B indicates that
December 2024 Groundwater Monitoring Report
Former Blanding Chevron | Blanding, Utah
January 10, 2025 | Terracon Project No. AL067004
Facilities | Environmental | Geotechnical | Materials 7
none of the petroleum constituents were detected above their analytical method reporting
limits. Please see historical analytical data provided in Table 2 (Appendix B).
Deep aquifer samples were collected from deep monitoring wells MW-4 and MW-10.
Benzene (779 µg/L) was identified above its Tier 1 screening criteria in MW-4. TPH-GRO
(1,660 µg/L) and TPH-DRO (1,700 µg/L) were identified in monitoring well MW-4, which
exceeds their ISLs but are below their Tier 1 criteria. All other petroleum constituent
concentrations were below ISLs or laboratory reporting limits in MW-4. TPH-DRO and
benzene were below laboratory reporting limits in the September 2024 monitoring event.
Historically, MW-4 had benzene concentrations above Tier 1 screening levels and toluene
concentrations above ISLs. Analytical results from MW-10 show that none of the
constituents analyzed were reported above their analytical method reporting limits during
this event. Historically, benzene has been reported in MW-10 at concentrations ranging from
non-detect to 743 µg/L, and was most recently detected at 100 µg/L in September 2016.
Overall, petroleum constituent concentrations have a decreasing trend over time where
samples were able to be collected. The appearance of LNAPL in MW-8 during the September
2024 monitoring event and continued presence of LNAPL in MW-7 may indicate that the
LNAPL plume may be migrating down-gradient from the tank basin area and/or the increase
in depth-to-groundwater is affecting the amount and distribution of LNAPL present in the
deep aquifer.
Terracon appreciates being of service to you on this project. If you have any questions,
require additional information, or need additional assistance, please contact us.
Appendix A
Exhibits
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terracon.com
Reviewed By:
Drawn By:
Oct 2024
Date:
AL067004
Project No.:
FORMER BLANDING CHEVRON
200 North Highway 191
Blanding, Utah
Topographic Map
1
PH. [phone]
Midvale, Utah 840476949 High Tech Drive
ABA
AST
DATA SOURCES:
ESRI WMS - World Aerial Imagery, OpenStreetMap
0 1 20.5
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Reviewed By:
Drawn By:
Oct 2024
Date:
AL067004
Project No.:
FORMER BLANDING CHEVRON
200 North Highway 191
Blanding, Utah
Site Map
2
PH. [phone]
Midvale, Utah 840476949 High Tech Drive
ABA
AST
DATA SOURCES:
ESRI WMS - World Aerial Imagery, OpenStreetMap
@A
@A
@A
@A
@A
@A
@A
@A
@AMW-4
MW-5
MW-3
MW-7
MW-8
MW-10
MW-3B
MW-8B
MW-4B
0 150 30075
Feet
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@A Shallow Monitoring Well
@A Deep Monitoring Well
Blanding City Well
Former UST Area
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Reviewed By:
Drawn By:
Dec 2024
Date:
AL067004
Project No.:
FORMER BLANDING CHEVRON
200 North Highway 191
Blanding, Utah
Shallow Aquifer Potentiometric Surface Map, December 2024
3
PH. [phone]
Midvale, Utah 840476949 High Tech Drive
ABA
AST
DATA SOURCES:
ESRI WMS - World Aerial Imagery, OpenStreetMap
&
@A
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@A94
f
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90 f
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MW-3B
90.07(0.04)
MW-8B
87.62
MW-4B
94.27
0 100 20050
Feet
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@A Shallow Monitoring Well with Relative Groundwater Elevation (ft) and LNAPL Thickness (ft)
Shallow Groundwater Elevation Isocontour (ft), December 2024
&Shallow Groundwater Flow Direction
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Exhibit
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Reviewed By:
Drawn By:
Dec 2024
Date:
AL067004
Project No.:
FORMER BLANDING CHEVRON
200 North Highway 191
Blanding, Utah
Deep Aquifer Potentiometric Surface Map, December 2024
4
PH. [phone]
Midvale, Utah 840476949 High Tech Drive
ABA
AST
DATA SOURCES:
ESRI WMS - World Aerial Imagery, OpenStreetMap
&
@A
@A
@A
@A
@A
@A
MW-4 23.8
MW-5
22.91(0.11)
MW-3
20.85(2.41)
MW-7
18.29(3.57)
MW-8
17.53(1.65)
MW-10 12.13
14 ft
16 ft
20 ft
18 ft
22 ft
0 150 30075
Feet
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@A Deep Monitoring Well with Relative Groundwater Elevation (ft) and LNAPL Thickness (ft)
Deep Groundwater Elevation Isocontour (ft), December 2024
&Deep Groundwater Flow Direction
Blanding City Well
Appendix B
Groundwater Data Tables
TABLE 1
Former Blanding Chevron / Facility ID 5000247, Release Site GFB
Well Construction and Groundwater Elevation Data
Terracon Project No. AL067004
Well ID
Well
Diameter
(inches)
Total Depth
(feet)
Screened
Interval
(feet)1
Relative Top
of Casing
Elevation
(feet)2
Date
Depth to
Water (feet
below top of
casing)
Relative
Ground Water
Elevation
(feet)2
Measured
Product
Thickness
(feet)
Corrected
Groundwater
Elevation
(feet)3
MW-2B 2 19.78 5-20 98.52 06/12/01 DRY NA NM NA
08/29/01 DRY NA NM NA
05/14/02 DRY NA NM NA
08/06/02 DRY NA NM NA
02/18/03 DRY NA NM NA
05/28/03 NM NM NM NA
11/05/03 19.21 79.31 ND 79.31
06/14/04 DRY NA NM NA
03/29/99 5.70 91.18 ND 91.18
04/13/99 5.36 91.52 ND 91.52
08/12/99 5.21 91.67 ND 91.67
06/12/01 5.34 91.54 ND 91.54
08/29/01 6.18 90.70 ND 90.70
05/14/02 7.33 89.55 ND 89.55
08/06/02 8.01 88.87 ND 88.87
11/11/02 8.66 88.22 ND 88.22
02/18/03 9.00 88.02 ND 88.02
05/28/03 7.49 89.42 ND 89.42
11/05/03 9.14 87.85 ND 87.85
06/14/04 7.81 89.09 ND 89.09
10/10/06 9.46 89.36 1.94 90.78
05/09/07 8.71 88.17 1.82 89.50
06/30/10 4.08 92.80 ND 92.80
02/14/13 6.47 90.41 ND 90.41
09/12/13 6.05 90.83 ND 90.83
07/22/14 7.23 89.65 ND 89.65
11/10/14 7.70 89.18 0.03 89.20
09/28/16 6.62 90.26 ND 90.26
05/08/18 8.95 87.93 ND 87.93
10/30/19 6.93 89.95 1.5 91.05
09/23/24 6.09 90.79 0.88 91.43
12/17/24 6.84 90.04 0.04 90.07
03/29/99 5.41 95.85 ND 95.85
04/13/99 5.10 96.16 ND 96.16
08/12/99 5.71 95.55 ND 95.55
06/12/01 5.59 95.67 ND 95.67
08/29/01 7.07 94.19 ND 94.19
05/14/02 7.04 94.22 ND 94.22
08/06/02 8.48 92.78 ND 92.78
11/11/02 8.92 92.35 ND 92.35
02/18/03 8.41 92.86 ND 92.86
05/28/03 7.27 93.99 ND 93.99
11/05/03 9.05 92.21 ND 92.21
06/14/04 8.04 93.22 ND 93.22
10/10/06 7.69 93.63 0.06 93.67
05/09/07 7.36 93.90 0.03 93.92
06/30/10 5.60 95.66 ND 95.66
02/13/13 7.82 93.44 ND 93.44
09/11/13 7.89 93.37 ND 93.37
07/23/14 8.33 92.93 ND 92.93
11/10/14 8.46 92.80 ND 92.80
09/28/16 7.98 93.28 ND 93.28
05/08/18 10.04 91.22 ND 91.22
10/30/19 8.29 92.97 ND 92.97
09/23/24 5.25 96.01 ND 96.01
12/17/24 6.99 94.27 ND 94.27
20.44MW-4B
(shallow,
unconfined)
4
MW-3B
(shallow,
unconfined)
4 20.37 10-20 96.88
10-20 101.26
Page 1 of 6
TABLE 1
Former Blanding Chevron / Facility ID 5000247, Release Site GFB
Well Construction and Groundwater Elevation Data
Terracon Project No. AL067004
Well ID
Well
Diameter
(inches)
Total Depth
(feet)
Screened
Interval
(feet)1
Relative Top
of Casing
Elevation
(feet)2
Date
Depth to
Water (feet
below top of
casing)
Relative
Ground Water
Elevation
(feet)2
Measured
Product
Thickness
(feet)
Corrected
Groundwater
Elevation
(feet)3
03/29/99 7.98 88.03 ND 88.03
04/13/99 7.61 88.40 ND 88.40
08/12/99 7.70 88.31 ND 88.31
06/12/01 7.63 88.38 ND 88.38
08/29/01 8.70 87.31 ND 87.31
05/14/02 9.10 86.91 ND 86.91
08/06/02 9.94 86.07 ND 86.07
11/11/02 10.74 85.28 ND 85.28
02/18/03 10.86 85.15 ND 85.15
05/28/03 9.56 86.45 ND 86.45
11/05/03 10.97 85.04 ND 85.04
06/14/04 10.00 86.01 ND 86.01
10/10/06 9.46 86.55 ND 86.55
05/09/07 9.27 86.74 ND 86.74
06/30/10 6.17 89.84 ND 89.84
02/13/13 8.82 87.19 ND 87.19
09/11/13 8.67 87.34 ND 87.34
07/21/14 9.03 86.98 ND 86.98
11/10/14 9.44 86.57 ND 86.57
09/28/16 8.39 87.62 ND 87.62
05/08/18 10.49 85.52 ND 85.52
10/30/19 8.69 87.32 ND 87.32
09/23/24 7.63 88.38 ND 88.38
12/17/24 8.39 87.62 ND 87.62
03/29/99 5.50 90.50 ND 90.50
04/13/99 5.22 90.78 ND 90.78
08/12/99 5.21 90.79 ND 90.79
06/12/01 5.21 90.79 ND 90.79
08/29/01 5.86 90.14 ND 90.14
05/14/02 6.68 89.32 ND 89.32
08/06/02 8.04 87.96 ND 87.96
11/11/02 9.10 86.91 ND 86.91
02/18/03 9.27 86.73 ND 86.73
05/28/03 NM NM NM NM
11/05/03 9.22 86.78 ND 86.78
06/14/04 8.18 87.82 ND 87.82
03/24/98 60.09 44.61 ND 44.61
07/16/98 61.06 43.64 ND 43.64
11/18/98 60.56 44.14 ND 44.14
02/19/99 60.32 44.38 ND 44.38
03/29/99 60.84 43.86 ND 43.86
04/13/99 60.51 44.19 ND 44.19
08/12/99 61.41 43.29 ND 43.29
06/12/01 62.31 42.39 ND 42.39
08/29/01 62.74 41.96 ND 41.96
05/14/02 62.93 41.77 ND 41.77
08/06/02 63.42 41.28 ND 41.28
11/11/02 63.57 41.14 ND 41.14
02/18/03 63.52 41.18 ND 41.18
05/28/03 NM NM NM NM
11/05/03 64.80 39.90 ND 39.90
06/14/04 65.54 39.16 ND 39.16
2
MW-1
(deep,
confined)
MW-8B
(shallow,
unconfined)
2 16.92
2
20.29
90.19 104.7070-90
MW-9B
(shallow,
unconfined)
10-20 96.00
5-17 96.01
Page 2 of 6
TABLE 1
Former Blanding Chevron / Facility ID 5000247, Release Site GFB
Well Construction and Groundwater Elevation Data
Terracon Project No. AL067004
Well ID
Well
Diameter
(inches)
Total Depth
(feet)
Screened
Interval
(feet)1
Relative Top
of Casing
Elevation
(feet)2
Date
Depth to
Water (feet
below top of
casing)
Relative
Ground Water
Elevation
(feet)2
Measured
Product
Thickness
(feet)
Corrected
Groundwater
Elevation
(feet)3
03/24/98 57.30 43.67 ND 43.67
07/16/98 57.78 43.19 ND 43.19
11/18/98 57.59 43.38 ND 43.38
02/19/99 57.49 43.48 ND 43.48
03/29/99 57.87 43.10 ND 43.10
04/13/99 57.65 43.32 ND 43.32
08/12/99 58.21 42.76 ND 42.76
06/12/01 58.98 41.99 ND 41.99
08/29/01 59.45 41.52 ND 41.52
05/14/02 60.00 40.97 ND 40.97
08/06/02 60.62 40.35 ND 40.35
11/11/02 61.00 39.98 ND 39.98
02/18/03 60.91 40.07 ND 40.07
05/28/03 NM NM NM NM
11/05/03 62.07 38.90 ND 38.90
06/14/04 62.59 38.38 ND 38.38
03/24/98 58.59 39.43 ND 39.43
07/16/98 59.26 38.76 ND 38.76
11/18/98 59.07 38.95 ND 38.95
02/19/99 58.85 39.17 ND 39.17
03/29/99 59.37 38.65 ND 38.65
04/13/99 59.00 39.02 ND 39.02
08/12/99 59.67 38.35 ND 38.35
06/12/01 60.53 37.49 ND 37.49
08/29/01 60.92 37.10 ND 37.10
05/14/02 61.37 36.65 ND 36.65
08/06/02 62.03 35.99 ND 35.99
11/11/02 62.31 35.71 ND 35.71
02/18/03 62.18 35.85 ND 35.85
05/28/03 63.01 35.01 ND 35.01
11/05/03 63.34 34.68 ND 34.68
06/14/04 64.06 33.96 ND 33.96
10/11/06 65.38 32.66 0.02 32.67
05/10/07 65.44 32.58 0.01 32.59
06/30/10 67.21 30.81 ND 30.81
02/14/13 68.01 30.01 ND 30.01
09/12/13 68.38 29.64 ND 29.64
07/22/14 68.98 29.04 ND 29.04
11/10/14 69.68 28.34 ND 28.34
09/28/16 70.45 27.57 0.04 27.60
05/08/18 71.87 26.15 0.09 26.22
10/30/19 73.22 24.80 0.08 24.86
09/23/24 78.93 19.09 2.41 20.85
12/17/24 79.37 18.65 2.88 20.75
70-90MW-2
(deep,
confined)
89.85MW-3
(deep,
confined)
2 100.9784.31
2 70-90 98.02
Page 3 of 6
TABLE 1
Former Blanding Chevron / Facility ID 5000247, Release Site GFB
Well Construction and Groundwater Elevation Data
Terracon Project No. AL067004
Well ID
Well
Diameter
(inches)
Total Depth
(feet)
Screened
Interval
(feet)1
Relative Top
of Casing
Elevation
(feet)2
Date
Depth to
Water (feet
below top of
casing)
Relative
Ground Water
Elevation
(feet)2
Measured
Product
Thickness
(feet)
Corrected
Groundwater
Elevation
(feet)3
03/24/98 60.15 42.51 ND 42.51
07/16/98 60.88 41.78 ND 41.78
11/18/98 60.62 42.04 ND 42.04
02/19/99 60.37 42.29 ND 42.29
03/29/99 60.96 41.70 ND 41.70
04/13/99 60.57 42.09 ND 42.09
08/12/99 62.38 40.28 ND 40.28
06/12/01 62.08 40.58 ND 40.58
08/29/01 62.61 40.05 ND 40.05
05/14/02 62.98 39.68 ND 39.68
08/06/02 63.54 39.12 ND 39.12
11/11/02 63.81 38.86 ND 38.86
02/18/03 63.69 38.98 ND 38.98
05/28/03 64.65 38.01 ND 38.01
11/05/03 64.89 37.77 ND 37.77
06/14/04 65.55 37.11 ND 37.11
10/11/06 66.67 35.99 ND 35.99
05/09/07 66.86 35.80 ND 35.80
06/29/10 68.65 34.01 ND 34.01
02/13/13 69.43 33.23 ND 33.23
09/11/13 69.78 32.88 ND 32.88
07/23/14 70.30 32.36 ND 32.36
11/10/14 70.13 32.53 ND 32.53
09/28/16 72.04 30.62 ND 30.62
05/08/18 73.45 29.21 ND 29.21
10/30/19 75.39 27.27 ND 27.27
09/24/24 78.86 23.80 ND 23.80
12/17/24 78.88 23.78 ND 23.78
03/24/98 59.13 41.33 ND 41.33
07/16/98 59.72 40.74 ND 40.74
11/18/98 59.60 40.86 ND 40.86
02/19/99 59.40 41.06 ND 41.06
03/29/99 60.41 40.05 ND 40.05
04/13/99 59.62 40.84 ND 40.84
08/12/99 61.99 38.47 ND 38.47
06/12/01 61.02 39.44 ND 39.44
08/29/01 61.51 38.95 ND 38.95
05/14/02 62.03 38.43 ND 38.43
08/06/02 62.59 37.87 ND 37.87
11/11/02 62.99 37.47 ND 37.47
02/18/03 62.82 37.64 ND 37.64
05/28/03 NM NM NM NM
11/05/03 63.98 36.48 ND 36.48
06/14/04 64.55 35.91 ND 35.91
10/11/06 65.77 34.72 0.03 34.74
05/09/07 66.01 34.45 ND 34.45
06/30/10 67.89 32.57 ND 32.57
02/13/13 68.71 31.75 ND 31.75
09/12/13 69.11 31.35 ND 31.35
07/21/14 69.65 30.81 ND 30.81
11/10/14 69.42 31.04 ND 31.04
09/28/16 71.34 29.12 ND 29.12
05/08/18 73.3 27.16 1.00 27.89
10/30/19 75.66 24.80 2.04 26.29
09/23/24 77.63 22.83 0.11 22.91
12/17/24 80.36 20.10 2.93 22.24
MW-4
(deep,
confined)
2 89.95
70-90 100.4689.94
102.6670-90
MW-5
(deep,
confined)
2
Page 4 of 6
TABLE 1
Former Blanding Chevron / Facility ID 5000247, Release Site GFB
Well Construction and Groundwater Elevation Data
Terracon Project No. AL067004
Well ID
Well
Diameter
(inches)
Total Depth
(feet)
Screened
Interval
(feet)1
Relative Top
of Casing
Elevation
(feet)2
Date
Depth to
Water (feet
below top of
casing)
Relative
Ground Water
Elevation
(feet)2
Measured
Product
Thickness
(feet)
Corrected
Groundwater
Elevation
(feet)3
03/29/99 61.68 38.24 ND 38.24
04/14/99 61.32 38.60 ND 38.60
08/12/99 62.09 37.83 ND 37.83
06/12/01 62.99 36.93 ND 36.93
08/29/01 63.33 36.59 ND 36.59
05/14/02 63.76 36.16 ND 36.16
08/06/02 64.46 35.46 ND 35.46
11/11/02 64.60 35.33 ND 35.33
02/18/03 64.55 35.37 ND 35.37
05/28/03 NM NM NM NM
11/05/03 65.65 34.27 ND 34.27
06/14/04 66.38 33.54 ND 33.54
10/11/06 65.37 34.57 0.02 34.58
05/10/07 67.84 32.08 ND 32.08
03/29/99 60.88 36.29 ND 36.29
04/14/99 60.61 36.56 ND 36.56
08/12/99 61.17 36.00 ND 36.00
06/12/01 62.14 35.03 ND 35.03
08/29/01 62.55 34.62 ND 34.62
05/14/02 63.06 34.11 ND 34.11
08/06/02 63.70 33.47 ND 33.47
11/11/02 63.99 33.18 ND 33.18
02/18/03 63.86 33.31 ND 33.31
05/28/03 NM NM NM NM
11/05/03 64.99 32.18 ND 32.18
06/14/04 65.55 31.62 ND 31.62
10/11/06 66.81 30.36 ND 30.36
05/10/07 67.14 30.03 ND 30.03
06/30/10 68.78 28.39 ND 28.39
02/13/13 69.62 27.55 ND 27.55
09/11/13 69.93 27.24 ND 27.24
07/21/14 70.46 26.71 ND 26.71
11/10/14 70.28 26.89 ND 26.89
09/28/16 72.00 25.17 0.5 25.54
05/08/18 73.10 24.07 0.62 24.52
10/30/19 76.80 20.37 2.84 22.44
09/23/24 81.49 15.68 3.57 18.29
12/17/24 80.01 17.16 1.52 18.27
03/29/99 62.02 34.56 ND 34.56
04/14/99 61.81 34.77 ND 34.77
08/12/99 62.22 34.36 ND 34.36
06/12/01 63.17 33.41 ND 33.41
08/29/01 63.66 32.92 ND 32.92
05/14/02 64.11 32.47 ND 32.47
08/06/02 64.72 31.86 ND 31.86
11/11/02 64.99 31.60 ND 31.60
02/18/03 64.85 31.73 ND 31.73
05/28/03 65.52 31.07 ND 31.07
11/05/03 65.94 30.64 ND 30.64
06/14/04 66.58 30.00 ND 30.00
10/12/06 67.72 28.86 ND 28.86
05/10/07 68.04 28.54 ND 28.54
06/30/10 69.55 27.03 ND 27.03
02/13/13 70.35 26.23 ND 26.23
09/11/13 70.70 25.88 ND 25.88
07/21/14 71.22 25.36 ND 25.36
11/10/14 70.98 25.60 ND 25.60
09/28/16 72.50 24.08 ND 24.08
05/08/18 73.80 22.78 ND 22.78
10/30/19 75.11 21.47 ND 21.47
09/24/24 80.25 16.33 1.65 17.53
12/17/24 79.92 16.66 0.98 17.38
90.14
90.09 70-90MW-8
(deep,
confined)
2
90.15 70-90 97.17
96.58
MW-7
(deep,
confined)
2
2MW-6
(deep,
confined)
99.9270-90
Page 5 of 6
TABLE 1
Former Blanding Chevron / Facility ID 5000247, Release Site GFB
Well Construction and Groundwater Elevation Data
Terracon Project No. AL067004
Well ID
Well
Diameter
(inches)
Total Depth
(feet)
Screened
Interval
(feet)1
Relative Top
of Casing
Elevation
(feet)2
Date
Depth to
Water (feet
below top of
casing)
Relative
Ground Water
Elevation
(feet)2
Measured
Product
Thickness
(feet)
Corrected
Groundwater
Elevation
(feet)3
06/12/01 65.20 28.60 ND 28.60
08/29/01 65.55 28.25 ND 28.25
05/14/02 66.06 27.74 ND 27.74
08/06/02 66.71 27.09 ND 27.09
11/11/02 67.03 26.77 ND 26.77
02/18/03 66.85 26.96 ND 26.96
05/28/03 67.39 26.42 ND 26.42
11/05/03 67.93 25.87 ND 25.87
06/14/04 68.46 25.34 ND 25.34
06/12/01 56.98 27.46 ND 27.46
08/29/01 57.38 27.06 ND 27.06
05/14/02 57.91 26.53 ND 26.53
08/06/02 58.58 25.86 ND 25.86
11/11/02 58.92 25.52 ND 25.52
02/18/03 58.75 25.69 ND 25.69
05/28/03 59.26 25.18 ND 25.18
11/05/03 59.81 24.63 ND 24.63
06/14/04 60.32 24.12 ND 24.12
10/12/06 61.63 22.81 ND 22.81
05/10/07 61.85 22.59 ND 22.59
06/30/10 63.37 21.07 ND 21.07
02/12/13 64.06 20.38 ND 20.38
09/11/13 65.61 18.83 ND 18.83
07/21/14 64.99 19.45 ND 19.45
11/10/14 64.64 19.80 ND 19.80
09/28/16 66.00 18.44 ND 18.44
05/08/18 67.12 17.32 ND 17.32
10/30/19 68.32 16.12 ND 16.12
09/24/24 72.31 12.13 ND 12.13
12/17/24 72.37 12.07 ND 12.07
1 = Screened intervals were taken from well logs
2 = Elevation, relative to an arbitrary datum of 100 feet
3 = Groundwater elevation corrected for the presence of free product using the following equation: hc = hm + (Ho)(ro/rw) where:
hm = Uncorrected groundwater elevation (ft)
Ho = Thickness of free product in well (ft)
ro = Density of product =0.73 g/mL (typical range for gasoline is from 0.71 - 0.77 g/mL)
rw = Density of water =1 g/mL
NM = Not Measured
ND = Not Detected
93.80
MW-10
(deep,
confined)
2 93.25 60-90
MW-9
(deep,
confined)
2 92.01 60-90
84.44
Page 6 of 6
TABLE 2
Former Blanding Chevron / Facility ID 5000247, Release Site GFB
Groundwater Analytical Results (g/L)
Terracon Project No. AL067004
Sample
Identification
Sample
Date
Depth to
Water (ft-
btoc)
Relative
Ground
Water
Elevation
(feet)1
TPH-GRO TPH-DRO MTBE Benzene Toluene Ethyl-
benzene
Total
Xylenes
Naph-
thalene
1,000 1,000 200 5 1,000 700 10,000 700
10,000 10,000 200 300 3,000 4,000 10,000 700
MW-2B 06/12/01 DRY NA NS NS NS NS NS NS NS NS
08/29/01 DRY NA NS NS NS NS NS NS NS NS
05/14/02 DRY NA NS NS NS NS NS NS NS NS
08/06/02 DRY NA NS NS NS NS NS NS NS NS
11/12/02 NM NM NS NS NS NS NS NS NS NS
02/18/03 DRY NA NS NS NS NS NS NS NS NS
05/29/03 NM NM NS NS NS NS NS NS NS NS
11/06/03 19.21 79.31 <500 <500 <2 <2 <2 <2 <6 <2
06/15/04 DRY NA NS NS NS NS NS NS NS NS
04/14/99 5.36 91.52 27,400 <500 62.3 1,990 2,130 223 1,870 223
08/13/99 5.21 91.67 12,200 <500 <100 1,150 1,780 729 3,130 414
06/12/01 5.34 91.54 46,800 6,700 <100 3,130 4,850 954 4,220 518
08/29/01 6.18 90.70 37,900 4,900 <102 3,580 5,770 1,060 4,520 427
05/15/02 7.33 89.55 36,200 3,400 <200 3,970 5,470 989 4,260 358
08/07/02 8.01 88.87 34,000 3,400 <20 2,250 3,110 656 2,870 422
11/12/02 8.66 88.22 40,100 4,700 <50 3,830 E 5,310 E 1,110 4850 E 497
02/18/03 8.86 88.02
05/29/03 7.46 89.42
11/06/03 9.03 87.85
06/15/04 7.79 89.09
10/10/06 9.46 89.36 (1.94')
05/09/07 8.71 88.17 (1.82')
06/30/10 4.08 92.80 20,000 <1,000 <20 2,760 3,390 942 3,470 593
02/14/13 6.47 90.41 19,900 2,300 <20 1,620 2,260 951 3,430 312
09/11/13 6.05 90.83 19,700 2,700 <20 1,830 2,650 925 3,400 423
07/22/14 7.23 89.65 26,800 3,700 <10 2,330 3,240 1,470 5,580 1,110
11/10/14 7.70 89.18 (0.03')
09/28/16 6.62 90.26 24,300 4,500 <50 2430 3710 1030 3,890 418
05/08/18 8.95 87.93 25,400 7,000 <5 1960 2640 1330 5,560 532
10/30/19 6.93 89.95 (1.5')
09/23/24 6.09 90.79 (0.88')
12/17/24 6.84 90.04 (0.04')
04/14/99 5.10 96.16 43,700 <500 48.3 3,760 2,010 894 5,530 383
08/13/99 5.71 95.55 29,600 <500 <200 5,290 1,700 1,740 10,300 656
06/12/01 5.59 95.67 55,600 6,200 <100 4,760 1,140 1,570 9,030 516
08/29/01 7.07 94.19 53,900 6,800 <102 5,180 1,450 2,020 11,600 599
05/14/02 7.04 94.22 58,400 4,100 <200 7,120 5,950 1,510 8,530 436
08/07/02 8.48 92.78 63,100 4,100 <500 6,930 7,000 1,370 7,890 <500
11/12/02 8.92 92.35 56,100 4,900 <100 6,890 E 7,624 E 1,311 7,050 399
02/18/03 8.41 92.86 55,700 5,700 <100 4,310 4,760 903 5,330 366
05/29/03 7.27 93.99 36,000 E 5,900 <34 4,700 E 4,200 E 380 4,500 180
11/06/03 9.05 92.21 50,900 6,880 <100 6,220 E 7,690 E 1,180 5,900 362
06/15/04 8.04 93.22 54,170 5,280 <100 6,994 7,937 809 5,990 <100
10/10/06 7.69 93.63 (0.06')
05/09/07 7.36 93.90 (0.03')
06/30/10 5.60 95.66 28,300 2,900 <20 2,490 2,500 1,570 6,440 686
02/13/13 7.82 93.44 21,700 1,400 <5 3,030 3,420 954 4,220 268
09/11/13 7.89 93.37 23,800 2,700 <25 3,600 4,100 1,190 5,220 446
07/23/14 8.33 92.93 20,100 1,700 <10 4,000 4,230 898 4,350 476
11/10/14 8.46 92.80 28,800 2,400 <20 4,260 4,160 921 5,490 549
09/28/16 7.98 93.28 NS NS NS NS NS NS NS NS
05/08/18 10.04 91.20 NS NS NS NS NS NS NS NS
10/30/19 8.29 92.97 21,200 5,700 <5 3,420 1,880 1,050 3,370 457
09/23/24 5.25 96.01 12,100 6,800 <8 1,780 621 792 1,700 692
12/17/24 6.99 94.27 10,300 3,800 <8 1,003 1,100 987 2,920 581
Initial Screening Levels (µg/L)
Tier 1 Screening Criteria (µg/L)
MW-3B
(shallow,
unconfined)
MW-4B
(shallow,
unconfined)
LNAPL
LNAPL LNAPL
LNAPL
LNAPL LNAPL
LNAPL
LNAPL
LNAPL
LNAPL
LNAPL
LNAPL
LNAPL
LNAPL
LNAPL
LNAPL
LNAPL
LNAPL
LNAPL
LNAPL
LNAPL
LNAPL
LNAPL LNAPL
1 of 6
TABLE 2
Former Blanding Chevron / Facility ID 5000247, Release Site GFB
Groundwater Analytical Results (g/L)
Terracon Project No. AL067004
Sample
Identification
Sample
Date
Depth to
Water (ft-
btoc)
Relative
Ground
Water
Elevation
(feet)1
TPH-GRO TPH-DRO MTBE Benzene Toluene Ethyl-
benzene
Total
Xylenes
Naph-
thalene
1,000 1,000 200 5 1,000 700 10,000 700
10,000 10,000 200 300 3,000 4,000 10,000 700
Initial Screening Levels (µg/L)
Tier 1 Screening Criteria (µg/L)
04/14/99 7.61 88.40 <500 <500 <2 5.9 <2 <2 <6 <2
08/13/99 7.70 88.31 <500 <500 <2 9 4.6 <2 <6 21.8
06/12/01 7.63 88.38 1,500 980 <2 322 26.3 4.8 18.9 19.3
08/29/01 8.70 87.31 <500 1,100 <3.3 52.0 4.3 <3.3 <9.9 15.9
05/15/02 9.10 86.91 570 <500 <10 138 31.2 <10 <30 <10
08/06/02 9.94 86.07 500 640 <2 92.3 5.1 <2 <6 13.2
11/12/02 10.74 85.28 2,700 1,700 <5 960 122 93.6 298 89.7
02/18/03 10.86 85.15 15,900 4,100 <10 2,040 494 355 683 194
05/29/03 9.56 86.45 13,000 2,700 <20 2,500 E 1,100 E 330 1,000 230
11/06/03 10.97 85.04 10,400 4,380 <20 2,380 E 241 394 635 227
06/15/04 10.00 86.01 15,660 E 4,290 <10 2,542 E 1,046 E 378 1,420 253
10/10/06 9.46 86.55 61 <2,000 <1 12 <1 <1 12 5
05/09/07 9.27 86.74 123 <2,000 <1 11 <1 <1 <3 5
06/30/10 6.17 89.84 <50 <1,000 <1 4 <1 <1 4 <2
02/13/13 8.82 87.19 <50 <1,000 <1 <1 <1 <1 <3 <2
09/11/13 8.67 87.34 <50 <1,000 <1 <1 <1 <1 <3 <2
07/21/14 9.03 86.98 272 <1,000 <1 91 13 30 19 7
11/10/14 9.44 86.57 124 <1,000 <1 6 2 4 <3 <2
09/28/16 8.39 87.62 <222 <200 <5 <2 <5 <5 <5 <5
05/08/18 10.49 85.52 <125 <1,000 <5 <5 <12 <12 <12 <12
10/30/19 8.69 87.32 <125 <1,000 <5 <5 <12 <12 <12 <12
09/23/24 7.63 88.38 <125 <1,000 <8 <5 <12 <12 <38 <12
12/17/24 8.39 87.62 <125 <1,000 <8 <5 <12 <12 <38 <12
04/14/99 5.22 90.78 <500 <500 <2 <2 <2 <2 <6 <2
08/13/99 5.21 90.79 <500 <500 <2 3 2.5 <2 <6 2.2
06/12/01 5.21 90.79 <500 <500 <2 <2 <2 <2 <6 <2
08/29/01 5.86 90.14 <500 <500 <2 <2 <2 <2 <6 <2
05/15/02 6.68 89.32 <500 <500 <2 <2 <2 <2 <6 <2
08/06/02 8.04 87.96 <500 <500 <2 <2 <2 <2 <6 <2
11/12/02 9.10 86.91 <500 <500 <2 <2 <2 <2 <6 <2
02/18/03 9.27 86.73 <500 <500 <2 <2 <2 <2 <6 <2
05/29/03 NM NM NS NS NS NS NS NS NS NS
11/06/03 9.22 86.78 NS NS NS NS NS NS NS NS
06/15/04 8.18 87.82 NS NS NS NS NS NS NS NS
03/24/98 60.09 44.61 <500 <500 <2 <2 <2 <2 <6 <2
07/16/98 61.06 43.64 <500 <500 <2 <2 <2 <2 <6 <2
11/18/98 60.56 44.14 <500 <500 <2 <2 <2 <2 <6 <2
02/19/99 60.32 44.38 <500 <500 <2 <2 <2 <2 <6 <2
04/14/99 60.51 44.19 <500 4,500 <2 <2 <2 <2 <6 <2
08/13/99 61.41 43.29 <500 <500 <2 <2 <2 <2 <6 <2
06/12/01 62.31 42.39 <500 <500 <2 <2 <2 <2 <6 <2
08/29/01 62.74 41.96 NS NS NS NS NS NS NS NS
05/14/02 62.93 41.77 <500 <500 <2 <2 <2 <2 <6 <2
08/06/02 63.42 41.28 NS NS NS NS NS NS NS NS
11/12/02 63.57 41.14 NS NS NS NS NS NS NS NS
02/18/03 63.52 41.18 NS NS NS NS NS NS NS NS
05/29/03 NM NM NS NS NS NS NS NS NS NS
11/06/03 64.80 39.90 NS NS NS NS NS NS NS NS
06/15/04 65.54 39.16 NS NS NS NS NS NS NS NS
MW-9B
(shallow,
unconfined)
MW-1
(deep, confined)
MW-8B
(shallow,
unconfined)
2 of 6
TABLE 2
Former Blanding Chevron / Facility ID 5000247, Release Site GFB
Groundwater Analytical Results (g/L)
Terracon Project No. AL067004
Sample
Identification
Sample
Date
Depth to
Water (ft-
btoc)
Relative
Ground
Water
Elevation
(feet)1
TPH-GRO TPH-DRO MTBE Benzene Toluene Ethyl-
benzene
Total
Xylenes
Naph-
thalene
1,000 1,000 200 5 1,000 700 10,000 700
10,000 10,000 200 300 3,000 4,000 10,000 700
Initial Screening Levels (µg/L)
Tier 1 Screening Criteria (µg/L)
03/24/98 57.30 43.67 <500 <500 <2 <2 <2 <2 <6 <2
07/16/98 57.78 43.19 <500 <500 <2 3.2 <2 <2 <6 <2
11/18/98 57.59 43.38 <500 <500 <2 2.9 <2 <2 <6 <2
02/19/99 57.49 43.48 <500 <500 <2 3.3 <2 <2 <6 <2
04/14/99 57.65 43.32 <500 <500 <2 <2 <2 <2 <6 <2
08/13/99 58.21 42.76 <500 <500 <2 <2 <2 <2 <6 <2
06/12/01 58.98 41.99 <500 <500 <2 <2 <2 <2 <6 <2
08/29/01 59.45 41.52 NS NS NS NS NS NS NS NS
05/14/02 60.00 40.97 <500 <500 <2 <2 <2 <2 <6 <2
08/06/02 60.62 40.35 NS NS NS NS NS NS NS NS
11/12/02 61.00 39.98 NS NS NS NS NS NS NS NS
02/18/03 60.91 40.07 NS NS NS NS NS NS NS NS
05/29/03 NM NM NS NS NS NS NS NS NS NS
11/06/03 62.07 38.90 NS NS NS NS NS NS NS NS
06/15/04 62.59 38.38 NS NS NS NS NS NS NS NS
03/24/98 58.59 39.43 4,500 <500 <5 488 611 67.1 449 41.4
07/16/98 59.26 38.76 10,300 <500 <50 1,700 2,250 185 1,480 80.6
11/19/98 59.07 38.95 5,000 <500 <2 717 754 69.9 512 40.3
02/19/99 58.85 39.17 5,900 <500 <10 864 923 53.4 497 22.9
04/14/99 59.00 39.02 84,000 <500 <100 4,920 6,250 360 3,470 141
08/13/99 59.67 38.35 12,900 <500 <100 2,310 2,930 238 2,030 79.9
06/12/01 60.53 37.49 45,600 7,800 <200 4,260 6,130 522 3,630 224
08/29/01 60.92 37.10 33,000 5,800 <102 3,570 5,740 521 3,900 198
05/15/02 61.37 36.65 51,500 6,100 <200 6,420 10,100 728 5,300 206
08/07/02 62.03 35.99 65,400 7,900 <500 6,990 11,300 881 6,020 <500
11/12/02 62.31 35.71 54,600 8,000 <65 6,160 E 10,200 E 964 6,230 E 360
02/18/03 62.18 35.85 75,600 8,100 <100 6,140 9,650 912 5,920 286
05/29/03 63.01 35.01 58,000 10,000 <100 5,800 E 9,000 E 650 5,800 310
11/06/03 63.34 34.68 47,400 8,050 <100 5,200 E 8,620 E 834 5,880 256
06/15/04 64.06 33.96 39,440 6,120 <100 4,494 5,795 <100 4,610 189
10/11/06 65.38 32.66 (0.02')
05/10/07 65.44 32.58 (0.01')
06/30/10 67.21 30.81 3,260 <1,000 <5 193 215 81 358 51
02/14/13 68.01 30.01 1,150 <1,000 <5 151 104 40 95 33
09/11/13 68.38 29.64 1,480 <1,000 1 52 66 21 131 31
07/22/14 68.98 29.04
11/10/14 69.68 28.34
09/28/16 70.45 27.60 (0.04')
05/08/18 71.87 26.22 (0.09')
10/30/19 73.22 24.80 (0.08')
09/23/24 78.93 19.09 (2.41')
12/17/24 79.37 18.65 (2.88')
MW-2
(deep, confined)
MW-3
(deep, confined)
LNAPL
LNAPL LNAPL
LNAPL
LNAPL LNAPL
LNAPL
LNAPL
LNAPL
LNAPL
LNAPL
LNAPLLNAPL
LNAPL LNAPL
LNAPL
LNAPL LNAPL
3 of 6
TABLE 2
Former Blanding Chevron / Facility ID 5000247, Release Site GFB
Groundwater Analytical Results (g/L)
Terracon Project No. AL067004
Sample
Identification
Sample
Date
Depth to
Water (ft-
btoc)
Relative
Ground
Water
Elevation
(feet)1
TPH-GRO TPH-DRO MTBE Benzene Toluene Ethyl-
benzene
Total
Xylenes
Naph-
thalene
1,000 1,000 200 5 1,000 700 10,000 700
10,000 10,000 200 300 3,000 4,000 10,000 700
Initial Screening Levels (µg/L)
Tier 1 Screening Criteria (µg/L)
03/24/98 60.15 42.51 1,900 <500 <5 7.1 37 15.3 97.7 16.8
07/16/98 60.88 41.78 700 <500 <2 169 324 4.7 181 12.7
11/19/98 60.62 42.04 <500 <500 <2 2.1 <2 <2 <6 <2
02/19/99 60.37 42.29 <500 <500 <2 <2 <2 <2 <6 <2
04/14/99 60.57 42.09 <500 <500 <2 <2 <2 <2 <6 <2
08/13/99 62.38 40.28 <500 <500 <2 3.7 3 <2 <6 <2
06/12/01 62.08 40.58 <500 <500 <2 19.3 37.9 <2 20.8 <2
08/29/01 62.61 40.05 1,000 880 <3.3 208 116 <3.3 137 4.1
05/14/02 62.98 39.68 650 <500 <20 108 93.8 <20 75.9 <20
08/07/02 63.54 39.12 6,700 790 <100 612 1,390 <100 689 <100
11/12/02 63.81 38.86 22,800 3,000 <20 2,390 E 4,790 E 20.7 2,440 E 138
02/18/03 63.69 38.98 5,700 3,000 <20 683 586 <20 397 28.0
05/29/03 64.65 38.01 14,000 2,500 <20 1,600 E 3,500 E 21 1,600 79
11/06/03 64.89 37.77 9,920 3,350 <20 804 686 <20 1,010 78
06/15/04 65.55 37.11 10,430 3,850 <10 706 1,002 E <10 1,590 110
10/11/06 66.67 35.99 6,470 <2,000 <10 866 1,280 39 698 134
05/09/07 66.86 35.80 9,700 <2,000 <5 <5 <5 105 3,010 243
06/29/10 68.65 34.01 17,900 <1,000 <20 5,180 4,830 169 2,440 306
02/13/13 69.43 33.23 17,500 2,900 <5 4,100 3,050 89 901 150
09/11/13 69.78 32.88 5,000 <1,000 <10 1,430 958 44 376 91
07/23/14 70.30 32.36 2,530 <1,000 <10 978 340 17 474 81
11/10/14 70.13 32.53 12,700 3,400 <5 3,560 1,690 57 750 180
09/28/16 72.04 30.62 NS NS NS NS NS NS NS NS
05/08/18 73.45 29.99 NS NS NS NS NS NS NS NS
10/30/19 75.39 27.27 4,740 1,900 <5 1,790 289 49 409 115
09/24/24 78.86 23.80 1,750 <1,000 <8 <5 <12 <12 <38 <12
12/17/24 78.88 23.78 1,660 1,700 <8 779 95 <12 164 39
03/24/98 59.13 41.33 33,700 <500 <2 <2 3 <2 10.2 3.3
07/16/98 59.72 40.74 118,000 <500 <2 1,160 4,170 1,050 5,590 437
11/19/98 59.60 40.86 137,000 <500 <50 178 1,310 400 2,880 218
02/19/99 59.40 41.06 8,000 <500 <10 50.1 341 56.1 495 22.6
04/14/99 59.62 40.84 8,700 <500 <25 <25 178 36.4 487 35.6
08/13/99 61.99 38.47 425,000 <500 <500 <500 1,310 <500 3,300 <500
06/12/01 61.02 39.44 22,100 19,400 <30 57.8 1,260 265 2,990 218
08/29/01 61.51 38.95 5,800 2,200 <20 16.7 217 44.7 611 46.9
05/14/02 62.03 38.43 730 560 <33 3.9 23.4 <33 31.1 17.8
08/07/02 62.59 37.87 <500 <500 <2 <2 <2 <2 <6 3.9
11/12/02 62.99 37.47 <500 <500 <2 <2 3.1 <2 <6 <2
02/18/03 62.82 37.64 <500 <500 <2 <2 3.9 <2 7.2 <2
05/29/03 NM NM NS NS NS NS NS NS NS NS
11/06/03 63.98 36.48 <500 <500 <2 2 8 <2 13 2
06/15/04 64.55 35.91 <500 <500 6 <2 3 <2 8 <2
10/11/06 65.77 34.72 (0.03')
05/09/07 66.01 34.45 66 <2,000 <1 1 1 <1 <3 7
06/30/10 67.89 32.57 199 <1,000 <1 39 34 2 40 <2
02/13/13 68.71 31.75 <50 <1,000 <1 1 2 <1 <3 <2
09/11/13 69.11 31.35 <50 <1,000 <1 3 5 2 7 <2
07/21/14 69.65 30.81 60 <1,000 <1 1 8 <1 32 4
11/10/14 69.42 31.04 452 1,000 <1 58 72 <1 44 <2
09/28/16 71.34 29.12 NS NS NS NS NS NS NS NS
05/08/18 73.30 27.64 (1.00')
10/30/19 75.66 24.80 (2.04')
09/23/24 77.63 22.83 (0.11')
12/17/24 80.36 20.10 (2.93')
LNAPL LNAPL
MW-5
(deep, confined)
MW-4
(deep, confined)
LNAPLLNAPL
LNAPL LNAPL
LNAPL LNAPL
LNAPL LNAPL
4 of 6
TABLE 2
Former Blanding Chevron / Facility ID 5000247, Release Site GFB
Groundwater Analytical Results (g/L)
Terracon Project No. AL067004
Sample
Identification
Sample
Date
Depth to
Water (ft-
btoc)
Relative
Ground
Water
Elevation
(feet)1
TPH-GRO TPH-DRO MTBE Benzene Toluene Ethyl-
benzene
Total
Xylenes
Naph-
thalene
1,000 1,000 200 5 1,000 700 10,000 700
10,000 10,000 200 300 3,000 4,000 10,000 700
Initial Screening Levels (µg/L)
Tier 1 Screening Criteria (µg/L)
04/14/99 61.32 38.60 1,800 <500 <2 64.2 75 2.2 54.3 <2
08/13/99 62.09 37.83 2,200 <500 <10 107 230 <10 300 18.2
06/12/01 62.99 36.93 5,200 1,800 <10 184 284 <10 646 80.7
08/29/01 63.33 36.59 3,300 1,600 <20 117 253 <20 621 67.1
05/14/02 63.76 36.16 3,500 770 <33 293 198 <33 425 76.1
08/07/02 64.46 35.46 2,700 860 <2 213 63.9 <2 135 42.3
11/12/02 64.60 35.33 690 960 <2 43.6 38.0 <2 73.6 12.5
02/18/03 64.55 35.37 1,700 3,100 <5 69.9 49.2 <5 136 35.9
05/29/03 NM NM NS NS NS NS NS NS NS NS
11/06/03 65.65 34.27 1,850 2,810 <2 150 E 66 <2 217 67
06/15/04 66.38 33.54 970 2,350 <2 68 11 <2 58 38 +
10/11/06 65.37 34.57 (0.02')
05/10/07 67.84 32.08 141 <2,000 <1 16 4 2 15 14
04/14/99 60.61 36.56 6,500 <500 <2 345 402 15.3 357 4.3
08/13/99 61.17 36 3,200 <500 <20 618 815 <20 549 <20
06/12/01 62.14 35.03 7,700 1,300 <25 1,240 850 25.6 558 35.7
08/29/01 62.55 34.62 4,500 1,200 <20 760 525 <20 625 40.1
05/14/02 63.06 34.11 18,300 1,200 <100 2,940 2,490 <100 2,170 108
08/06/02 63.70 33.47 16,900 1,400 <100 2,080 1,600 <100 1,670 106
11/12/02 63.99 33.18 13,700 1,900 <20 2,400 E 1,700 E 35.4 1,690 E 87.7
02/18/03 63.86 33.31 27,100 4,200 <25 3,110 2,330 61.6 2,390 151
05/29/03 NM NM NS NS NS NS NS NS NS NS
11/06/03 64.99 32.18 21,800 4,800 <100 4,000 2,650 <100 2,470 132
06/15/04 65.55 31.62 26,100 4,610 <100 4,411 2,577 <100 2,810 107+
10/11/06 66.81 30.36 2,150 <2,000 <1 470 104 <1 164 13
05/10/07 67.14 30.03 8,620 <2,000 <1 5,220 2,700 34 3,220 110
06/30/10 68.78 28.39 1,360 <1,000 <1 756 191 7 132 42
02/13/13 69.62 27.55 1,560 <1,000 <1 498 95 18 55 21
09/11/13 69.93 27.24 1,320 <1,000 <5 432 50 16 42 36
07/21/14 70.46 26.71 1,850 <1,000 <1 1,260 214 65 149 61
11/10/14 70.28 26.89 2,720 <1,000 <5 901 204 35 126 34
09/28/16 72.00 25.91 (0.50')
05/08/18 73.10 24.07 (0.62')
10/30/19 76.80 20.37 (2.84')
09/23/24 81.49 15.68 (3.57')
12/17/24 80.01 17.16 (1.52')
04/14/99 61.81 34.77 5,600 <500 <2 916 525 4.9 370 4.7
08/13/99 62.22 34.36 2,100 <500 <20 610 450 20.3 358 <20
06/12/01 63.17 33.41 3,600 900 <25 528 336 <25 319 <25
08/29/01 63.66 32.92 6,400 1,600 <20 1,300 734 25.8 746 32.9
05/15/02 64.11 32.47 1,900 <500 <10 475 99.1 <10 159 11.2
08/06/02 64.72 31.86 2,900 590 <20 642 93.5 <20 265 <20
11/12/02 64.99 31.60 2,000 950 <2 551 E 70.3 E <2 227 E 15.5
02/18/03 64.85 31.73 4,600 3,800 <10 747 236 <10 357 28.1
05/29/03 65.52 31.07 <500 <500 <2.0 56 7.8 <2.0 22 <2.0
11/06/03 65.94 30.64 <500 <500 <2 <2 <2 <2 <6 <2
06/15/04 66.58 30.00 <500 <500 <2 <2 <2 <2 <6 <2
10/12/06 67.77 28.81 79 <2,000 <1 9 <1 <1 <3 <1
05/10/07 68.04 28.54 315 <2,000 <1 98 43.0 <1 102 15
06/30/10 69.55 27.03 108 <1,000 <1 12 3 <1 6 5
02/13/13 70.35 26.23 <50 <1,000 <1 3 <1 <1 <3 <2
09/11/13 70.70 25.88 <50 <1,000 <1 9 2 <1 6 <2
07/21/14 71.22 26.36 <50 <1,000 <1 9 4 <1 7 4
11/10/14 70.98 26.60 265 <1,000 <1 20 1 <1 <3 <2
09/28/16 72.50 24.08 NS NS NS NS NS NS NS NS
10/30/19 75.11 21.47 <125 <1,000 <5 <5 <12 <12 <12 <12
09/24/24 80.25 16.33 (1.65')
12/17/24 79.92 16.66 (0.98')
06/12/01 65.20 28.60 <500 <500 <2 <2 <2 <2 <6 <2
08/29/01 65.55 28.25 <500 <500 <2 <2 <2 <2 <6 <2
05/14/02 66.06 27.74 <500 <500 <2 <2 <2 <2 <6 <2
08/06/02 66.71 27.09 <500 <500 <2 <2 <2 <2 <6 <2
11/11/02 67.03 26.77 <500 <500 <2 <2 2.9 <2 <6 <2
02/18/03 66.85 26.96 <500 <500 <2 <2 <2 <2 <6 <2
05/29/03 67.39 26.42 <500 <500 <2 <2 <2 <2 <6 <2
11/06/03 67.93 25.87 <500 <500 <2 <2 <2 <2 <6 <2
06/15/04 68.46 25.34 <500 <500 <2 <2 <2 <2 <6 <2
LNAPL LNAPL
LNAPL LNAPL
LNAPL
LNAPL LNAPL
MW-7
(deep, confined)
MW-6
(deep, confined)
MW-9
(deep, confined)
MW-8
(deep, confined)
LNAPL
LNAPL
LNAPL
LNAPL
LNAPL
LNAPL
LNAPL
LNAPL LNAPL
5 of 6
TABLE 2
Former Blanding Chevron / Facility ID 5000247, Release Site GFB
Groundwater Analytical Results (g/L)
Terracon Project No. AL067004
Sample
Identification
Sample
Date
Depth to
Water (ft-
btoc)
Relative
Ground
Water
Elevation
(feet)1
TPH-GRO TPH-DRO MTBE Benzene Toluene Ethyl-
benzene
Total
Xylenes
Naph-
thalene
1,000 1,000 200 5 1,000 700 10,000 700
10,000 10,000 200 300 3,000 4,000 10,000 700
Initial Screening Levels (µg/L)
Tier 1 Screening Criteria (µg/L)
06/12/01 56.98 27.46 1,800 1,000 <10 131 112 12.5 200 <12.9
08/29/01 57.38 27.06 <500 <500 <2 15.5 24.1 <2 10.5 <2
05/14/02 57.91 26.53 6,000 960 <33 554 75.5 <33 1,190 119
08/06/02 58.58 25.86 7,100 1,500 <33 743 128 <33 1,190 167
11/11/02 58.92 25.52 <500 <500 <2 <2 <2 <2 <6 <2
02/18/03 58.75 25.69 <500 <500 <2 <2 <2 <2 <6 <2
05/29/03 59.26 25.18 <500 <500 <2 25 <2 <2 49 <2
11/06/03 59.81 24.63 <500 <500 <2 <2 3 <2 <6 <2
06/15/04 60.32 24.12 <500 <500 <2 <2 <2 <2 <6 <2
10/12/06 61.63 22.81 <50 <2,000 <1 <1 <1 <1 <3 <1
05/10/07 61.85 22.59 70 <2,000 <1 1 <1 <1 <3 <1
06/30/10 63.37 21.07 107 <1,000 <1 35 11 2 9 <2
02/12/13 64.06 20.38 76 <1,000 <1 48 <1 <1 <3 <2
09/11/13 65.61 18.83 131 <1,000 <1 82 <1 <1 <3 <2
07/21/14 64.99 19.45 95 <1,000 <1 51 <1 <1 <3 <2
11/10/14 64.64 19.80 <50 <1,000 <1 10 1 <1 <3 <2
09/28/16 66.00 18.44 <222 <200 <5 100 <5 <5 <5 <5
05/08/18 67.12 17.34 <125 <1,000 <5 <5 <12 <12 <12 <12
10/30/19 68.32 16.12 <125 <1,000 <5 <5 <12 <12 <12 <12
09/24/24 72.31 12.13 <125 <1,000 <8 <5 <12 <12 <38 <12
12/17/24 72.37 12.07 <125 <1,000 <8 <5 <12 <12 <38 <12
05/15/02 NA NA <500 <500 <2 <2 <2 <2 <6 <2
08/06/02 NA NA <500 <500 <2 <2 <2 <2 <6 <2
11/12/02 NA NA <500 <500 <2 <2 <2 <2 <6 <2
02/18/03 NA NA <500 <500 <2 <2 <2 <2 <6 <2
05/29/03 NA NA NS NS NS NS NS NS NS NS
11/06/03 NA NA <500 <500 <2 <2 <2 <2 <6 <2
06/15/04 NA NA <500 <500 <2 <2 <2 <2 <6 <2
10/12/06 NA NA <50 <2,000 <1 <1 <1 <1 <3 <1
05/10/07 NA NA <50 <2,000 <1 <1 <1 <1 <3 <1
06/30/10 NA NA <50 <1,000 <1 <1 <1 <1 <3 <2
02/12/13 NA NA <50 <1,000 <1 <1 <1 <1 <3 <2
09/11/13 NA NA <50 <1,000 <1 <1 <1 <1 <3 <2
07/21/14 NA NA <50 <1,000 <1 <1 <1 <1 <3 <2
11/10/14 NA NA <50 <1000 <1 <1 <1 <1 <3 <2
09/28/16 NA NA <222 <200 <5 <2 <5 <5 <5 <5
05/08/18 NA NA
10/30/19 NA NA
09/24/24 NA NA <125 <1,000 <8 <5 <12 <12 <38 <12
12/18/24 NA NA <125 <1,000 <8 <5 <12 <12 <38 <12
Explanation of Abbreviations
1 = LNAPL thickness, where available, in parentheses NS = Not Sampled
NM = Not Measured Bold Analytical result exceeds Initial Screening Level
NA = Not Available LNAPL = Light Non-Aqueous Phase Liquid
µg/L = Micrograms per liter
NS
Blanding
Municipal
Well
MW-10
(deep, confined)
NS - Well Off Line
6 of 6
Appendix C
Chain of Custody and Laboratory Data Sheets
The analyses presented on this report were performed in accordance with the
National Environmental Laboratory Accreditation Program (NELAP) unless
noted in the comments, flags, or case narrative. If the report is to be used for
regulatory compliance, it should be presented in its entirety, and not be
altered.
Client Service Contact: 801.262.7299
Terracon IHI
Attn: Andrew Turner
6949 South High Tech Drive
Midvale, UT 84047
Work Order: 24L1562
Project: DERR Blanding Chevron LUST,
Blanding AL067004
12/27/2024
Approved By:
Andrew Royer, Project Manager
9632 South 500 West Sandy, Utah 84070
Serving the Intermountain West since 1953
801.262.7299 Main 866.792.0093 Fax www.ChemtechFord.com
Page 1 of 11
xx
Chemtech-Ford Laboratories
Serving the Intermountain West Since 1953
Certificate of Analysis
9632 South 500 West
Sandy, UT 84070
O:[phone] F: [phone]
www.ChemtechFord.com
Terracon IHI
Andrew Turner
6949 South High Tech Drive
Midvale, UT 84047
PO#:
Receipt:
Date Reported:
Project Name:
AL067004
12/18/24 16:04 @ 7.4 °C
12/27/2024
DERR Blanding Chevron LUST, Blanding
AL067004
Sample ID: MW-4
Lab ID: 24L1562-01Matrix: Water
Flag(s)Units
Analysis
Date/Time
Date Sampled: 12/17/24 13:10
Preparation
Date/Time
Sampled By: JR Murphy
Minimum
Reporting
Limit MethodResult
Diesel Range with Silica Gel Cleanup
mg/L 12/19/2412/19/241.0 EPA 8015 C1.7Diesel Range Organics
MBTEXn
mg/L 12/20/2412/20/240.005 EPA 8260D/5030B0.779Benzene
mg/L 12/20/2412/20/240.012 EPA 8260D/5030BNDEthylbenzene
mg/L 12/20/2412/20/240.008 EPA 8260D/5030BNDMethyl-tert-butyl ether (MTBE)
mg/L 12/20/2412/20/240.012 EPA 8260D/5030B0.039Naphthalene
mg/L 12/20/2412/20/240.012 EPA 8260D/5030B0.095Toluene
mg/L 12/20/2412/20/240.038 EPA 8260D/5030B0.164Xylenes, total
mg/L 12/20/2412/20/240.125 EPA 8260D/5030B1.66Gasoline Range Organics
Project Name: DERR Blanding Chevron LUST, Blanding AL06700 CtF WO#: 24L1562
www.ChemtechFord.com
Page 2 of 11Page 2 of 11
xx
Chemtech-Ford Laboratories
Serving the Intermountain West Since 1953
Certificate of Analysis
9632 South 500 West
Sandy, UT 84070
O:[phone] F: [phone]
www.ChemtechFord.com
Terracon IHI
Andrew Turner
6949 South High Tech Drive
Midvale, UT 84047
PO#:
Receipt:
Date Reported:
Project Name:
AL067004
12/18/24 16:04 @ 7.4 °C
12/27/2024
DERR Blanding Chevron LUST, Blanding
AL067004
Sample ID: MW-4B
Lab ID: 24L1562-02Matrix: Water
Flag(s)Units
Analysis
Date/Time
Date Sampled: 12/17/24 14:10
Preparation
Date/Time
Sampled By: JR Murphy
Minimum
Reporting
Limit MethodResult
Diesel Range with Silica Gel Cleanup
mg/L 12/20/2412/19/241.0 EPA 8015 C3.8Diesel Range Organics
MBTEXn
mg/L 12/20/2412/20/240.100 EPA 8260D/5030B1.03Benzene
mg/L 12/20/2412/20/240.012 EPA 8260D/5030B0.987Ethylbenzene
mg/L 12/20/2412/20/240.008 EPA 8260D/5030BNDMethyl-tert-butyl ether (MTBE)
mg/L 12/20/2412/20/240.012 EPA 8260D/5030B0.581Naphthalene
mg/L 12/20/2412/20/240.012 EPA 8260D/5030B1.10Toluene
mg/L 12/20/2412/20/240.750 EPA 8260D/5030B2.92Xylenes, total
mg/L 12/20/2412/20/240.125 EPA 8260D/5030B10.3Gasoline Range Organics
Project Name: DERR Blanding Chevron LUST, Blanding AL06700 CtF WO#: 24L1562
www.ChemtechFord.com
Page 3 of 11Page 3 of 11
xx
Chemtech-Ford Laboratories
Serving the Intermountain West Since 1953
Certificate of Analysis
9632 South 500 West
Sandy, UT 84070
O:[phone] F: [phone]
www.ChemtechFord.com
Terracon IHI
Andrew Turner
6949 South High Tech Drive
Midvale, UT 84047
PO#:
Receipt:
Date Reported:
Project Name:
AL067004
12/18/24 16:04 @ 7.4 °C
12/27/2024
DERR Blanding Chevron LUST, Blanding
AL067004
Sample ID: MW-8B
Lab ID: 24L1562-03Matrix: Water
Flag(s)Units
Analysis
Date/Time
Date Sampled: 12/17/24 16:00
Preparation
Date/Time
Sampled By: JR Murphy
Minimum
Reporting
Limit MethodResult
Diesel Range with Silica Gel Cleanup
mg/L 12/20/2412/19/241.0 EPA 8015 CNDDiesel Range Organics
MBTEXn
mg/L 12/20/2412/20/240.005 EPA 8260D/5030BNDBenzene
mg/L 12/20/2412/20/240.012 EPA 8260D/5030BNDEthylbenzene
mg/L 12/20/2412/20/240.008 EPA 8260D/5030BNDMethyl-tert-butyl ether (MTBE)
mg/L 12/20/2412/20/240.012 EPA 8260D/5030BNDNaphthalene
mg/L 12/20/2412/20/240.012 EPA 8260D/5030BNDToluene
mg/L 12/20/2412/20/240.038 EPA 8260D/5030BNDXylenes, total
mg/L 12/20/2412/20/240.125 EPA 8260D/5030BNDGasoline Range Organics
Project Name: DERR Blanding Chevron LUST, Blanding AL06700 CtF WO#: 24L1562
www.ChemtechFord.com
Page 4 of 11Page 4 of 11
xx
Chemtech-Ford Laboratories
Serving the Intermountain West Since 1953
Certificate of Analysis
9632 South 500 West
Sandy, UT 84070
O:[phone] F: [phone]
www.ChemtechFord.com
Terracon IHI
Andrew Turner
6949 South High Tech Drive
Midvale, UT 84047
PO#:
Receipt:
Date Reported:
Project Name:
AL067004
12/18/24 16:04 @ 7.4 °C
12/27/2024
DERR Blanding Chevron LUST, Blanding
AL067004
Sample ID: MW-10
Lab ID: 24L1562-04Matrix: Water
Flag(s)Units
Analysis
Date/Time
Date Sampled: 12/17/24 18:20
Preparation
Date/Time
Sampled By: JR Murphy
Minimum
Reporting
Limit MethodResult
Diesel Range with Silica Gel Cleanup
mg/L 12/24/2412/23/241.0 EPA 8015 CNDDiesel Range Organics
MBTEXn
mg/L 12/20/2412/20/240.005 EPA 8260D/5030BNDBenzene
mg/L 12/20/2412/20/240.012 EPA 8260D/5030BNDEthylbenzene
mg/L 12/20/2412/20/240.008 EPA 8260D/5030BNDMethyl-tert-butyl ether (MTBE)
mg/L 12/20/2412/20/240.012 EPA 8260D/5030BNDNaphthalene
mg/L 12/20/2412/20/240.012 EPA 8260D/5030BNDToluene
mg/L 12/20/2412/20/240.038 EPA 8260D/5030BNDXylenes, total
mg/L 12/20/2412/20/240.125 EPA 8260D/5030BNDGasoline Range Organics
Project Name: DERR Blanding Chevron LUST, Blanding AL06700 CtF WO#: 24L1562
www.ChemtechFord.com
Page 5 of 11Page 5 of 11
xx
Chemtech-Ford Laboratories
Serving the Intermountain West Since 1953
Certificate of Analysis
9632 South 500 West
Sandy, UT 84070
O:[phone] F: [phone]
www.ChemtechFord.com
Terracon IHI
Andrew Turner
6949 South High Tech Drive
Midvale, UT 84047
PO#:
Receipt:
Date Reported:
Project Name:
AL067004
12/18/24 16:04 @ 7.4 °C
12/27/2024
DERR Blanding Chevron LUST, Blanding
AL067004
Sample ID: BMW
Lab ID: 24L1562-05Matrix: Water
Flag(s)Units
Analysis
Date/Time
Date Sampled: 12/18/24 10:30
Preparation
Date/Time
Sampled By: JR Murphy
Minimum
Reporting
Limit MethodResult
Diesel Range with Silica Gel Cleanup
mg/L 12/24/2412/23/241.0 EPA 8015 CNDDiesel Range Organics
MBTEXn
mg/L 12/20/2412/20/240.005 EPA 8260D/5030BNDBenzene
mg/L 12/20/2412/20/240.012 EPA 8260D/5030BNDEthylbenzene
mg/L 12/20/2412/20/240.008 EPA 8260D/5030BNDMethyl-tert-butyl ether (MTBE)
mg/L 12/20/2412/20/240.012 EPA 8260D/5030BNDNaphthalene
mg/L 12/20/2412/20/240.012 EPA 8260D/5030BNDToluene
mg/L 12/20/2412/20/240.038 EPA 8260D/5030BNDXylenes, total
mg/L 12/20/2412/20/240.125 EPA 8260D/5030BNDGasoline Range Organics
Project Name: DERR Blanding Chevron LUST, Blanding AL06700 CtF WO#: 24L1562
www.ChemtechFord.com
Page 6 of 11Page 6 of 11
xx
Chemtech-Ford Laboratories
Serving the Intermountain West Since 1953
Certificate of Analysis
9632 South 500 West
Sandy, UT 84070
O:[phone] F: [phone]
www.ChemtechFord.com
Terracon IHI
Andrew Turner
6949 South High Tech Drive
Midvale, UT 84047
PO#:
Receipt:
Date Reported:
Project Name:
AL067004
12/18/24 16:04 @ 7.4 °C
12/27/2024
DERR Blanding Chevron LUST, Blanding
AL067004
Sample ID: Trip Blank
Lab ID: 24L1562-06Matrix: Water
Flag(s)Units
Analysis
Date/Time
Date Sampled: 12/17/24 0:00
Preparation
Date/Time
Sampled By: JR Murphy
Minimum
Reporting
Limit MethodResult
MBTEXn
mg/L 12/20/2412/20/240.005 EPA 8260D/5030BNDBenzene
mg/L 12/20/2412/20/240.012 EPA 8260D/5030BNDEthylbenzene
mg/L 12/20/2412/20/240.008 EPA 8260D/5030BNDMethyl-tert-butyl ether (MTBE)
mg/L 12/20/2412/20/240.012 EPA 8260D/5030BNDNaphthalene
mg/L 12/20/2412/20/240.012 EPA 8260D/5030BNDToluene
mg/L 12/20/2412/20/240.038 EPA 8260D/5030BNDXylenes, total
mg/L 12/20/2412/20/240.125 EPA 8260D/5030BNDGasoline Range Organics
Project Name: DERR Blanding Chevron LUST, Blanding AL06700 CtF WO#: 24L1562
www.ChemtechFord.com
Page 7 of 11Page 7 of 11
xx
Chemtech-Ford Laboratories
Serving the Intermountain West Since 1953
Certificate of Analysis
9632 South 500 West
Sandy, UT 84070
O:[phone] F: [phone]
www.ChemtechFord.com
Terracon IHI
Andrew Turner
6949 South High Tech Drive
Midvale, UT 84047
PO#:
Receipt:
Date Reported:
Project Name:
AL067004
12/18/24 16:04 @ 7.4 °C
12/27/2024
DERR Blanding Chevron LUST, Blanding
AL067004
Report Footnotes
Abbreviations
ND = Not detected at the corresponding Minimum Reporting Limit (MRL).
1 mg/L = one milligram per liter or 1 mg/kg = one milligram per kilogram = 1 part per million.
1 ug/L = one microgram per liter or 1 ug/kg = one microgram per kilogram = 1 part per billion.
1 ng/L = one nanogram per liter or 1 ng/kg = one nanogram per kilogram = 1 part per trillion.
On calculated parameters, there may be a slight difference between summing the rounded values shown on the report
vs the unrounded values used in the calculation.
Project Name: DERR Blanding Chevron LUST, Blanding AL06700 CtF WO#: 24L1562
www.ChemtechFord.com
Page 8 of 11Page 8 of 11
Page 9 of 11
QC Report for Work Order (WO) - 24L1562
% Rec RPD RPD Max MRL DFResultSpk ValueLimitsSource ConcAnalyte
Blank - EPA 8015 C
QC Sample ID: BYL0927-BLK1 Batch: BYL0927
Date Prepared: 12/19/2024 Date Analyzed: 12/19/2024
Diesel Range Organics ND 1.0 1.00
QC Sample ID: BYL1043-BLK1 Batch: BYL1043
Date Prepared: 12/23/2024 Date Analyzed: 12/24/2024
Diesel Range Organics ND 1.0 1.00
LCS - EPA 8015 C
QC Sample ID: BYL0927-BS1 Batch: BYL0927
Date Prepared: 12/19/2024 Date Analyzed: 12/19/2024
Diesel Range Organics 96.2 50 - 150 38 40.0 1.0 1.00
QC Sample ID: BYL1043-BS1 Batch: BYL1043
Date Prepared: 12/23/2024 Date Analyzed: 12/24/2024
Diesel Range Organics 107 50 - 150 43 40.0 1.0 1.00
Matrix Spike - EPA 8015 C
QC Sample ID: BYL0927-MS1 QC Source Sample: XXXXXXX-XXBatch: BYL0927
Date Prepared: 12/19/2024 Date Analyzed: 12/19/2024
Diesel Range Organics 91.4 50 - 150 37 ND 40.0 1.0 1.00
QC Sample ID: BYL1043-MS1 QC Source Sample: XXXXXXX-XXBatch: BYL1043
Date Prepared: 12/23/2024 Date Analyzed: 12/24/2024
Diesel Range Organics 100 50 - 150 41 1 40.0 1.0 1.00
Matrix Spike Dup - EPA 8015 C
QC Sample ID: BYL0927-MSD1 QC Source Sample: XXXXXXX-XXBatch: BYL0927
Date Prepared: 12/19/2024 Date Analyzed: 12/19/2024
Diesel Range Organics 98.7 7.70 50 - 150 20 39 ND 40.0 1.0 1.00
QC Sample ID: BYL1043-MSD1 QC Source Sample: XXXXXXX-XXBatch: BYL1043
Date Prepared: 12/23/2024 Date Analyzed: 12/24/2024
Diesel Range Organics 100 0.0938 50 - 150 20 41 1 40.0 1.0 1.00
CtF WO#: 24L1562
www.ChemtechFord.com Page 10 of 11
QC Report for Work Order (WO) - 24L1562
% Rec RPD RPD Max MRL DFResultSpk ValueLimitsSource ConcAnalyte
Blank - EPA 8260D
QC Sample ID: BYL1018-BLK1 Batch: BYL1018
Date Prepared: 12/20/2024 Date Analyzed: 12/20/2024
Benzene ND 0.0004 1.00
Ethylbenzene ND 0.001 1.00
Methyl-tert-butyl ether (MTBE)ND 0.0006 1.00
Naphthalene ND 0.001 1.00
Toluene ND 0.001 1.00
Xylenes, total ND 0.003 1.00
LCS - EPA 8260D
QC Sample ID: BYL1018-BS1 Batch: BYL1018
Date Prepared: 12/20/2024 Date Analyzed: 12/20/2024
Benzene 97.4 70 - 130 0.010 0.0100 0.0004 1.00
Ethylbenzene 104 70 - 130 0.010 0.0100 0.001 1.00
Methyl-tert-butyl ether (MTBE)72.4 70 - 130 0.007 0.0100 0.0006 1.00
Naphthalene 104 70 - 130 0.010 0.0100 0.001 1.00
Toluene 97.2 70 - 130 0.010 0.0100 0.001 1.00
Xylenes, total 108 70 - 130 0.032 0.0300 0.003 1.00
Matrix Spike - EPA 8260D
QC Sample ID: BYL1018-MS1 QC Source Sample: XXXXXXX-XXBatch: BYL1018
Date Prepared: 12/20/2024 Date Analyzed: 12/20/2024
Benzene 80.0 70 - 130 0.100 ND 0.125 0.005 1.00
Ethylbenzene 86.5 70 - 130 0.108 ND 0.125 0.012 1.00
Methyl-tert-butyl ether (MTBE)77.2 70 - 130 0.096 ND 0.125 0.008 1.00
Naphthalene 85.7 70 - 130 0.107 ND 0.125 0.012 1.00
Toluene 79.5 70 - 130 0.099 ND 0.125 0.012 1.00
Xylenes, total 88.6 70 - 130 0.332 ND 0.375 0.038 1.00
Matrix Spike Dup - EPA 8260D
QC Sample ID: BYL1018-MSD1 QC Source Sample: XXXXXXX-XXBatch: BYL1018
Date Prepared: 12/20/2024 Date Analyzed: 12/20/2024
Benzene 80.7 0.871 70 - 130 20 0.101 ND 0.125 0.005 1.00
Ethylbenzene 87.0 0.576 70 - 130 25 0.109 ND 0.125 0.012 1.00
Methyl-tert-butyl ether (MTBE)84.9 9.50 70 - 130 20 0.106 ND 0.125 0.008 1.00
Naphthalene 97.1 12.5 70 - 130 25 0.121 ND 0.125 0.012 1.00
Toluene 81.1 1.99 70 - 130 20 0.101 ND 0.125 0.012 1.00
Xylenes, total 90.0 1.53 70 - 130 20 0.338 ND 0.375 0.038 1.00
CtF WO#: 24L1562
www.ChemtechFord.com Page 11 of 11