DERR-2024-004361

6952 South High Tech Drive Ste. B
Midvale, Utah 84047
P [phone]
Terracon.com
Facilities | Environmental | Geotechnical | Materials 1
Cover Page
Quarterly Groundwater Monitoring
Report; December 2023
Brent Redd Property
148 East Center Street Monticello, Utah
Facility ID #5000003 Release ID GZQ
January 3, 2024 | Terracon Project No. AL067003
Prepared for:
Utah Department of Environmental Quality
Division of Environmental Response and Remediation
Salt Lake City, Utah
6952 South High Tech Drive Ste. B
Midvale, Utah 84047
P [phone]
Terracon.com
Facilities | Environmental | Geotechnical | Materials i
Cover Letter
January 3, 2024
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:Quarterly Groundwater Monitoring Report
Brent Redd Facility
148 East Center Street, Monticello, Utah
Facility Identification No. 5000003, Release ID GZQ
Terracon Project No. AL067003
Dear Mr. Crim:
Terracon Consultants, Inc. (Terracon) is pleased to submit this Quarterly Groundwater
Monitoring Report documenting the second quarterly groundwater sampling event conducted
under Work Assignment GZQ-57 at the Brent Redd facility (Facility ID 5000003, Release ID
GZQ), located at 148 East Center Street, Monticello, Utah.
Terracon has performed this work pursuant to Work Plan GZQ-56-TER dated August 21, 2023.
This work was conducted under Terracon's contract (Contract Number 216383) with the
Division of Environmental Response and Remediation.
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 Amy Austin
Project Manager Authorized Project Reviewer
Utah-Certified UST Consultant #0238
Facilities | Environmental | Geotechnical | Materials ii
Table Of Contents
1.0 Introduction ................................................................................ 1
1.1 Site Description ..................................................................................... 1
1.2 Scope of Services ................................................................................... 1
1.3 Standard of Care .................................................................................... 1
1.4 Additional Scope Limitations .................................................................... 1
1.5 Reliance ................................................................................................ 2
2.0 Groundwater Sampling Event......................................................... 2
2.1 Groundwater Sample Collection ............................................................... 2
2.2 General Observations ............................................................................. 2
3.0 Laboratory Analytical Methods ....................................................... 3
4.0 Data Evaluation ........................................................................... 3
4.1 Groundwater Sample Results ................................................................... 3
4.2 Quality Control ....................................................................................... 4
5.0 Findings And Conclusions .............................................................. 4
Facilities | Environmental | Geotechnical | Materials iii
APPENDICES
Appendix A Exhibits
Exhibit 1:Topographic Site Overview
Exhibit 2:Site Diagram
Exhibit 3:Groundwater Elevation Map, December 2023
Exhibit 4: TPH-GRO Concentrations, December 2023
Exhibit 5: TPH-DRO Concentrations, December 2023
Exhibit 6:Benzene Concentrations, December 2023
Appendix B Data Tables
Table 1:Well Construction and Groundwater Elevation Data
Table 2:Groundwater Analytical Results
Appendix C Chain of Custody and Laboratory Data Sheets
Groundwater Monitoring Report; 2nd Event
Brent Redd | Monticello, Utah
January 3, 2024 | Terracon Project No. AL067003
Facilities | Environmental | Geotechnical | Materials 1
1.0 Introduction
1.1 Site Description
Terracon conducted a groundwater monitoring event at the Brent Redd facility (Facility ID
5000003, Release ID GZQ), located at 148 East Center Street, Monticello, Utah. Exhibit 1
(Appendix A) presents a topographic map of the area. Exhibit 2 (Appendix A) is a site
diagram that shows monitoring well locations.
1.2 Scope of Services
The work objective of Work Assignment GZQ-57-TER was to collect groundwater samples
from eleven existing on- and off-site monitoring wells to assess the current groundwater
conditions. This is the second event of six quarterly groundwater monitoring events under
Work Assignment GZQ-57-TER.
1.3 Standard of Care
Terracon’s services were performed 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 to prepare the report. These
services were performed in accordance with the scope of services agreed with you, our
client, as reflected in our proposal, and were not restricted by ASTM E1903-19.
1.4 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 services. 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 recommendations are based solely upon data
obtained at the time and within the scope of these services.
Groundwater Monitoring Report; 2nd Event
Brent Redd | Monticello, Utah
January 3, 2024 | Terracon Project No. AL067003
Facilities | Environmental | Geotechnical | Materials 2
1.5 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 Groundwater Sampling Event
2.1 Groundwater Sample Collection
On December 12, 2023, Terracon collected groundwater samples from eleven monitoring
wells located at the site and a down-gradient property (Monticello Inn): Groundwater
samples were collected from monitoring wells B-3R, MW-5R, MW-7, MW-14, MW-15, MW-
16, MW-17, MW-18, MW-19, MW-20, and MW-21. Two quality control samples consisting of
a trip blank and a field blank, were also collected.
Prior to collecting the groundwater samples, each well was purged of three well volumes to
remove stagnant water from the well casings prior to sampling. Monitoring wells B-3R, MW-
15, and MW-16 were purged dry, then allowed to recover prior to sampling. A slight sheen
was observed on the purge water from monitoring wells B-3R and MW-14. Purge water was
thin spread across the surface in the vicinity of 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 (e.g., stormwater catch basins, other monitoring wells, utilities,
etc.) or residential property.
2.2 General Observations
Depth-to-water measurements and groundwater elevations are presented in Table 1
(Appendix B). Groundwater elevations at the site were measured to range between 7025.21
and 7032.77 feet above mean sea level (msl).
The groundwater gradient at the site was determined using ArcGIS Pro and scaling the area
in order to interpolate locations of contour lines to show the gradient. The direction of
groundwater flow is generally toward the east (Exhibit 3, Appendix A). The calculated
groundwater gradient and associated flow direction were generally consistent with the flow
directions observed during previous monitoring events. Free product was not observed in
any monitoring wells during this sampling event.
Groundwater Monitoring Report; 2nd Event
Brent Redd | Monticello, Utah
January 3, 2024 | Terracon Project No. AL067003
Facilities | Environmental | Geotechnical | Materials 3
Terracon had installed passive light non-aqueous phase liquid (LNAPL) recovery equipment:
Durham Geo SoakEase product-selective absorbent socks and stainless-steel canisters in
monitoring wells B-3R and MW-7 during past sampling events. Product was not observed in
these wells during this event and the absorbent socks were removed and not replaced.
3.0 Laboratory Analytical Methods
All groundwater samples were collected and placed in laboratory-prepared containers,
labeled, and placed on ice in a cooler and transported to Chemtech-Ford Laboratory in
Sandy, Utah.
The groundwater samples were submitted for analysis of methyl tertiary-butyl ether,
benzene, toluene, ethylbenzene, total xylenes, and naphthalene (MBTEXN) and total
petroleum hydrocarbons gasoline-range organics (TPH-GRO) using EPA Method 8260B, and
total petroleum hydrocarbons diesel-range organics (TPH-DRO) using EPA Method 8015C.
The field blank and trip blank were analyzed for MBTEXN and TPH-GRO.
The samples were analyzed using the following methods:
Analysis Sample type No. Of
Samples Laboratory method
BTEXN, MTBE and TPH-
GRO Groundwater 13 EPA Method 8260B
TPH-DRO Groundwater 11 EPA Method 8015C
The executed chain-of-custody form and laboratory data sheets are provided in Appendix C.
4.0 Data Evaluation
4.1 Groundwater Sample Results
Results of the groundwater sampling event are summarized in Table 2 (Appendix B).
Sample locations are shown on Exhibit 2 (Appendix A).
As presented in Table 2 (Appendix B), petroleum hydrocarbons were reported above the
laboratory method reporting limits in ten of the wells sampled.
TPH-GRO concentrations exceeded the Initial Screening Level (ISL) in monitoring
wells MW-5R, MW-7, MW-14, and MW-15. TPH-GRO concentrations exceeded the
Tier 1 Screening Level in monitoring wells B-3R, MW-16, and MW-17.
Groundwater Monitoring Report; 2nd Event
Brent Redd | Monticello, Utah
January 3, 2024 | Terracon Project No. AL067003
Facilities | Environmental | Geotechnical | Materials 4
TPH-DRO concentrations exceeded the ISL in monitoring wells B-3R, MW-14, MW-16,
MW-17, and MW-18. No concentration exceeded the Tier 1 Screening Level for TPH-
DRO.
Benzene concentrations exceeded the ISL in monitoring wells MW-7, MW-14, and
MW-20. Benzene concentrations exceeded the Tier 1 Screening Level in monitoring
wells MW-3R, MW-5R, MW-15, MW-16, MW-17, and MW-18.
Isoconcentration contour maps for TPH-GRO, TPH-DRO, and benzene are presented as
Exhibits 4, 5, and 6 (Appendix A), respectively.
4.2 Quality Control
Quality control for the sampling program was provided by using standardized sample
collection and handling methods, documenting pertinent field information, and keeping
chain-of-custody records, as well as using a Utah-certified laboratory. All sampling
procedures followed Terracon’s Standard Operating Procedures and industry practices.
A review of the field procedures indicates that standard operating procedures were followed
with regards to sample collection, handling, and documentation. The quality control samples
(field and trip blank) did not report constituents above laboratory reporting limits.
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 were within acceptable limits set by the laboratory,
except where noted. Naphthalene was flagged in MW-19, MW-20, MW-21, Field Blank, and
Trip Blank with a J-LOW-L qualifier, which indicates the reported concentration is low, due
to low recovery of Laboratory Control Samples (LCS). As naphthalene concentrations
reported in these samples were all non-detect and the detection limit is well below the ISL
of 700 ug/L this qualifier is not likely to affect the usability of the data. MTBE was also
flagged in B-3R, MW-14, MW-15, MW-16, and MW-17 with a J-LOW-L qualifier. As MTBE in
these samples were all non-detect and the detection limit is well below the ISL of 200 ug/L,
this qualifier is not likely to affect the usability of the data.
5.0 Findings And Conclusions
Petroleum hydrocarbon concentrations remain elevated at the site and at the property
boundaries. Monitoring wells B-3R, MW-16, and MW-17 continue to exhibit the highest
petroleum constituent concentrations across the site. Free product had previously been
observed in monitoring wells B-3R, MW-5, MW-7, and MW-16 between 2002 and 2013. Free
product was not observed for this event.
For the 2022 groundwater monitoring event, concentrations of benzene and TPH exceeding
ISLs migrated past the north and eastern property boundary, as demonstrated by analytical
Groundwater Monitoring Report; 2nd Event
Brent Redd | Monticello, Utah
January 3, 2024 | Terracon Project No. AL067003
Facilities | Environmental | Geotechnical | Materials 5
results from well MW-5R on the north property boundary and MW-7 located on the eastern-
adjoining Monticello Inn property.
For this current event, concentrations of dissolved benzene and TPH were reported that
exceed the ISLs both on the property and extend off-site onto the east adjoining property.
The concentration of TPH-GRO exceeded the Tier 1 Screening Level on the site down-
gradient of the source and exceeded the ISL off-site. The concentration of TPH-DRO
exceeded the ISL both on-site and off-site. The concentration of benzene exceeded the Tier
1 Screening Level both on the property and to the north and east.
Concentrations of dissolved petroleum hydrocarbons exceeding UDEQ screening levels
persist on the property and off-site. A review of historical data shows periodic fluctuation of
petroleum hydrocarbon concentrations in groundwater across the site. Unstable
concentrations of the dissolved petroleum constituents observed may be associated with
changing groundwater elevations. High dissolved phase concentrations of benzene and TPH
observed at monitoring wells B-3R, MW-16, and MW-17 suggest a petroleum hydrocarbon
source may remain in the subsurface.
Appendix A
Exhibits
Appendix B
Data Tables
Table 2
Brent Redd Property
148 East Center Street, Monticello, UT
(Facility ID 5000003, Release Site GZQ)
Groundwater Analytical Results (g/L)
Sample
Location Sample Date
Depth to
Water
(ft-btoc)
TPH-GRO TPH-DRO MTBE Benzene Toluene Ethyl-
benzene
Total
Xylene
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
11/08/91 15.76 <200 NA NA 40.8 39.7 23 61.2 <5
10/10/95 10.41 <500 NA NA 18.7 2.4 <2 9.3 <2
02/01/96 14.49 <500 NA NA 12.8 <2 <2 <6 <2
09/10/96 15.71 <500 NA NA <2 13.5 5.2 39.4 4
12/10/96 14.54 <500 NA NA 23.6 <2 <2 <6 <2
03/12/97 9.70 1,500 NA 456 302 <10 <10 <30 <10
06/12/97 9.28 <500 NA 218 235 5.6 7.8 9.7 <2
10/01/97 10.36 <500 NA 115 137 3.5 6.4 <6 <2
12/10/97 12.51 <500 NA 95.2 53.9 <2 2.4 <6 <2
03/26/98 11.39 <500 NA 72.2 32.1 <2 <2 <6 <2
07/14/98 10.82 <500 NA 89.5 146 <2 <2 <6 <2
01/11/99 13.30 <500 NA 334 80.9 <2 <2 <6 <2
04/28/99 12.35 <500 NA 242 54.5 <2 <2 <6 <2
07/20/99 12.44 <500 NA 166 122 <2 <2 <6 <2
10/13/99 12.38 <500 NA 109 82.5 <2 <2 <6 <2
05/24/00 13.15 3,800 NA 199 1,100 27.3 13.5 69.9 <10
08/09/00 12.76 1,800 NA 209 684 19.3 19.0 22.4 <2
11/07/00 12.42 6,300 NA 123 1,280 62.6 29.2 57.6 <5
02/08/01 13.49 <500 NA 60.3 74.1 4.6 2.9 <6 <2
05/08/01 13.00 3,000 NA 236 885 46.5 51.8 58.9 6.0
08/14/01 12.33 <500 NA 125 32.3 <2 2.1 <6 3.2
08/08/02 17.43 <500 <500 147 <2 5.0 <10 <30 <10
11/14/02 18.41 <500 <500 86.7 <2 <2 <2 <6 <2
02/19/03 19.58 <500 <500 83.8 12.6 <2 <2 <6 <2
05/28/03 19.34 <500 <500 <2 4.6 <2 <2 <6 <2
03/24/04 18.93 <500 <500 94 22 3 <2 <6 <2
10/10/06 10.79 54 <2,000 194 10 <1 <1 <3 <1
05/08/07 14.42 <50 <2,000 376 2 <1 <1 <3 <1
11/12/09 14.28 <20 <500 710 16 <2 <2 <2 <2
06/29/10 9.82 1,300 636 523 1,260 <2 5.99 4.81 3.37
02/14/13 16.81 <50 <1,000 109 <1 <1 <1 <3 <2
09/10/13 17.82 <50 <1,000 22 <1 <1 <1 <3 <2
11/16/13 17.85 <50 <1,000 5 <1 <1 <1 <3 <2
07/22/14 19.15 <50 <1,000 1 <1 <1 <1 <3 <2
05/14/15 15.13 <50 <1,000 2 1 <1 1 6 2
05/03/16 13.42 <222 <1,000 9 <2 <5 <5 <5 <5
11/18/16 15.68 <50 <1,000 <2 <2 <5 <5 <5 <5
06/06/18 18.88 <125 <1,000 7 <5 <12 <12 <12 <12
04/16/19 10.32 <125 <1,000 59 15 <12 <12 <12 <12
10/09/19 NM
06/25/20 NM
05/24/00 13.87 114,000 NA <200 17,300 9,500 727 8,160
08/09/00 13.90 149,100 NA <100 18,200 7,830 989 8,660 240
11/07/00 13.19 115,500 NA <100 18,200 5,790 826 6,910 181
02/08/01 15.28 118,600 NA <500 19,500 10,200 1,010 8,440 <500
05/08/01 13.50 92,700 NA <100 15,100 11,400 672 6,890 213
08/14/01 12.85 120,800 NA <200 20,700 18,200 647 9,110 350
08/08/02 17.93 139,000 7,700 <1,000 25,100 18,500 968 9,510 <1,000
11/13/02 18.96
02/19/03 NM
05/27/03 NM
03/23/04 19.53
10/09/06 11.90 74,600 <2,000 <5 19,200 8,970 1,130 9,720 338
05/08/07 14.99
11/12/09 14.69 50,000 12,000 <40 18,000 2,500 1,400 10,000 380
06/29/10 10.33 47,900 29,200 <20 23,600 1,390 1,360 11,000 418
02/14/13 17.32
09/10/13 18.29
11/18/13 18.31
07/22/14 19.84
05/14/15 15.81 43,500 3,600 <1 17,100 277 1,050 9,580 443
05/03/16 14.20 30,100 4,700 <5 11,800 176 810 6,380 390
11/18/16 16.08 36,000 8,900 <200 12,700 <500 1,210 8,600 <500
06/06/18 19.31 36,200 10,300 <5 10,100 194 1,050 6,840 406
04/17/19 10.93 32,300 16,400 <5 5,620 125 1,150 6,060 375
10/09/19 15.64 39,000 15,400 <5 6,850 154 1,520 9,440 406
06/25/20 16.32 29,700 9,000 <100 8,040 <250 1,070 6,760 318
01/27/22 19.52
04/21/22 19.48
07/28/22 19.70
10/20/22 19.50
09/27/23 14.45 26,300 7,000 <5 5,930 80 1,200 5,080 313
12/12/23 15.62 25,300 8,900 <5 5,440 103 1,070 4,980 319
Not sampled as per Work Assignment GZQ-49-TER
Not sampled as per Work Assignment GZQ-49-TER
B-2
Insufficient water column
Insufficient water column
B-3R
Well abandoned
LNAPL
LNAPL
Insufficient water column
LNAPL
LNAPL
LNAPL
Not Sampled - purged dry with no recovery after 24 hours
Initial Screening Levels (ug/L)
TIER 1 Screening Criteria (ug/L)
LNAPL
LNAPL
LNAPL
Insufficient water column
Page 1 of 4 Terracon Consultants
Table 2
Brent Redd Property
148 East Center Street, Monticello, UT
(Facility ID 5000003, Release Site GZQ)
Groundwater Analytical Results (g/L)
Sample
Location Sample Date
Depth to
Water
(ft-btoc)
TPH-GRO TPH-DRO MTBE Benzene Toluene Ethyl-
benzene
Total
Xylene
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 (ug/L)
TIER 1 Screening Criteria (ug/L)
10/11/95 10.43 94,800 NA NA 17,200 12,300 2,110 8,880 <400
02/01/96 14.46 55,700 NA NA 14,300 5,520 1,080 5,670 620
06/21/96 15.61 49,800 NA NA 17,000 5,100 1,180 5,120 249
09/10/96 15.50 35,300 NA NA 14,800 4,160 1,050 4,610 214
12/10/96 14.50 49,500 NA NA 17,400 5,460 1,160 5,930 315
03/12/97 10.28 49,200 NA <100 21,500 7,340 1,290 6,700 316
06/12/97 9.26 43,400 NA <175 18,000 3,170 1,060 4,830 422
10/01/97 10.27 50,200 NA <25 17,360 6,250 1,240 6,680 415
12/10/97 12.43 54,300 NA <143 25,300 8,400 1,510 8,400 405
03/26/98 11.50 48,800 NA <100 22,200 6,870 1,380 7,150 323
07/14/98 9.85 48,400 NA <200 24,100 9,370 1,340 7,280 275
01/11/99 13.38 38,700 NA <100 22,800 7,450 1,510 7,180 441
04/28/99 12.87 136,000 NA <100 14,100 5,310 1,120 5,770 384
07/20/99 12.62 41,100 NA <100 22,900 6,650 1,460 6,910 361
10/13/99 12.52 32,400 NA <200 20,300 4,840 1,250 6,150 429
05/24/00 13.25 92,800 NA <200 19,100 4,330 987 4,840 271
08/09/00 12.84 17,100 NA <20 2,710 720 112 937 44.3
11/07/00 12.86 39,800 NA <100 17,400 3,900 1,050 4,710 183
02/08/01 14.93 90,400 NA <500 19,000 4,060 1,070 4,980 1,040
05/08/01 13.20 79,300 NA <100 17,300 4,560 1,110 5,160 246
08/16/01 11.50 82,300 NA <100 19,000 5,910 1,280 6,060 266
08/08/02 17.18 104,000 2,900 <400 20,100 5,960 1,600 8,630 <400
11/13/02 18.50
02/19/03 19.24
05/27/03 18.85
03/23/04 18.28
10/09/06 11.43
05/08/07 14.50
11/12/09 14.04
06/29/10 9.84 25,400 39,600 <20 442 477 1,330 8,930 581
02/14/13 16.58 17,700 178,000 <20 2100 103 898 6,050 1,330
09/10/13 16.03 11,200 2,000 <20 749 105 631 4,440 263
11/18/13 17.49 13,600 2,400 <5 1,110 118 743 5,620 296
07/22/14 18.66 12,800 4,300 <5 1,040 109 665 3,340 326
05/14/15 15.12 7,560 1,800 <1 614 32 317 1,950 194
05/03/16 13.70 10,600 3,100 <5 614 24 470 2,620 247
11/18/16 15.60 17,200 4,300 <100 2,770 <250 935 4,820 <250
06/06/18 NM
04/17/19 NM
10/09/19 NM
06/25/20 NM
01/27/22 18.30 3,980 1,100 <5 754 <12 332 772 62
04/21/22 18.11 4,490 1,400 <5 679 <12 388 856 74
07/28/22 19.22 1,920 <1,000 <5 482 <12 157 281 31
10/20/22 18.34 2,190 <1,000 <5 466 <12 184 329 21
09/27/23 13.17 1,920 <1,000 <5 601 <12 117 162 <12
12/12/23 14.15 1,130 <1,000 <5 495 <12 99 91 12
10/11/95 10.25 <500 NA NA <2 <2 <2 <6 <2
02/01/96 14.31 <500 NA NA <2 <2 <2 <6 <2
06/21/96 14.92 <500 NA NA <2 <2 <2 <6 <2
09/10/96 15.05 <500 NA NA <2 <2 <2 <6 <2
12/10/96 14.51 <500 NA NA <2 <2 <2 <6 <2
03/12/97 9.83 <500 NA 403 12.9 <2 <2 <6 <2
06/12/97 8.72 <500 NA 750 3.4 <2 <2 <6 <2
10/01/97 9.97 <500 NA 306 <2 <2 <2 <6 <2
12/10/97 12.24 <500 NA 276 <2 <2 <2 <6 <2
03/26/98 11.35 <500 NA 261 <2 <2 <2 <6 <2
07/14/98 9.99 <500 NA 167 <2 <2 <2 <6 <2
01/11/99 13.03 <500 NA 102 <2 <2 <2 <6 <2
04/28/99 12.46 <500 NA 76.5 <2 <2 <2 <6 <2
07/20/99 11.84 <500 NA 104 <2 <2 <2 <6 <2
10/13/99 11.91 <500 NA 149 <2 <2 <2 <6 <2
05/24/00 12.49 <500 NA 85.3 3.3 <2 <2 <6 <2
08/09/00 12.36 <500 NA 128 <2 <2 <2 <6 <2
11/07/00 12.82 <500 NA 134 <2 <2 <2 <6 <2
02/08/01 14.67 <500 NA 110 <2 <2 <2 <6 <2
05/08/01 12.80 <500 NA 124 <2 <2 <2 <6 <2
08/14/01 12.10 <500 NA 131 <2 <2 <2 <6 <2
08/09/02 16.75 <500 <500 13.6 <2 <2 <2 <6 <2
11/14/02 16.70 <500 <500 8.6 <2 <2 <2 <6 <2
02/19/03 18.45 <500 <500 5.7 <2 <2 <2 <6 <2
11/12/09 14.36
06/29/10 9.61 4,770 1,930 30.2 619 28.9 137 788 97.4
02/14/13 NM NA NA NA NA NA NA NA NA
09/10/13 16.09 4,660 <1,000 <5 <5 <5 43 215 50
11/18/13 16.53 1,000 <1,000 <5 <5 <5 17 68 13
07/22/14 17.82 1,500 <1,000 <1 2 <1 34 126 16
05/13/15 14.68 1,870 <1,000 <1 24 <1 15 66 15
05/03/16 13.42 16,800 24,300 <5 60 <5 72 333 103
11/18/16 15.52 7,310 5,600 <3 68 <8 31 98 16
06/06/18 17.81 2,940 1,600 <5 28 <12 14 50 <12
04/17/19 9.95 6,560 2,200 <5 193 <12 31 87 20
10/09/19 14.05 13,800 13,900 <5 62 <12 32 86 21
06/25/20 14.57 2,180 1,500 <5 53 <12 14 28 <12
01/27/22 17.99 3,420 1,300 <5 33 <12 <12 14 <12
04/21/22 17.68 1,740 <1,000 <5 50 <12 <12 13 <12
07/28/22 18.45 3,220 1,600 <5 40 <12 14 24 <12
10/20/22 18.00 2,010 1,000 <5 23 <12 <12 <12 <12
09/27/23 12.96 4,780 1,300 <5 133 <12 23 49 <12
12/12/23 13.19 2,230 <1,000 <5 39 <12 <12 17 <12
MW-5
LNAPL
LNAPL
LNAPL
Not Sampled - well casing damaged and debris in well
MW-7
Not Sampled - well casing damaged and debris in well
Not Sampled - well casing damaged and debris in well
MW-5R
LNAPL
Well abandoned
LNAPL
LNAPL
LNAPL
LNAPL
Not Sampled - well casing damaged and debris in well
Page 2 of 4 Terracon Consultants
Table 2
Brent Redd Property
148 East Center Street, Monticello, UT
(Facility ID 5000003, Release Site GZQ)
Groundwater Analytical Results (g/L)
Sample
Location Sample Date
Depth to
Water
(ft-btoc)
TPH-GRO TPH-DRO MTBE Benzene Toluene Ethyl-
benzene
Total
Xylene
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 (ug/L)
TIER 1 Screening Criteria (ug/L)
05/24/00 12.99 600 NA <5 135 <5 <5 <15 <5
08/09/00 12.64 1,700 NA <5 21.9 <5 <5 <15 <5
11/07/00 12.30 1,900 NA <5 7.2 <5 <5 <15 <5
02/08/01 14.20 2,700 NA <2 95.9 <2 <2 <6 <2
05/08/01 12.70 3,100 NA <2 74.0 <2 <2 15.9 4.7
08/14/01 11.98 3,200 NA <2 45.2 <2 <2 <6 <2
08/08/02 17.04 1,000 640 <5 12.0 <5 <5 <15 <5
11/13/02 18.10 600 <500 <2 112 <2 <2 <6 <2
02/19/03 19.42 6,400 4,300 <2 104 9.5 <2 10.3 3.3
05/28/03 19.21 980 <500 <2 60 3.3 <2 <6 <2
03/24/04 18.93 16,900 E 2,170 <10 106 14 19 27 44
10/10/06 10.95 1,210 <2,000 <1 9 <1 <1 <3 16
05/09/07 13.92 <50 <2,000 <1 14 <1 <1 <3 <1
11/12/09 13.96 14,000 3,900 <2 76 <2 2.6 3.5 <2
06/29/10 9.43 5,450 8,150 <2 75.2 <2 6.81 12.5 7.19
02/14/13 16.58 6,330 <1000 <1 3 <1 <1 <3 <2
09/10/13 17.57 2,260 <1,000 <1 2 <1 <1 <3 <2
11/19/13 17.67 2,830 <1,000 <1 4 <1 <1 <3 <2
07/22/14 18.95 1,700 <1,000 <1 5 <1 <1 <3 7
05/14/15 15.01 2,170 1,100 <1 24 <1 2 10 4
05/04/16 13.29 1,450 <1,000 <5 21 <5 <5 10 <5
11/18/16 15.26 2,020 <1000 <2 10 <5 <5 <5 <5
06/06/18 18.62 11,300 1,800 <5 <5 <12 <12 <12 <12
04/17/19 10.33 6,580 1,500 <5 71 <12 18 54 15
10/09/19 14.66 3,820 2,300 <5 22 <12 <12 <12 <12
06/25/20 15.38 2,810 2,400 <5 34 <12 <12 <12 <12
01/27/22 19.21 3,080 <1,000 <5 <5 <12 <12 <12 <12
04/21/22 19.16 1,900 <1,000 <5 <5 <12 <12 <12 <12
07/28/22 20.44 798 <1,000 <5 6 <12 <12 <12 <12
10/20/22 19.38 2,170 <1,000 <5 26 <12 <12 <12 <12
09/27/23 13.75 2,000 1,100 <5 29 <12 <12 <12 <12
12/12/23 14.95 1,420 1,400 <5 33 <12 <12 <12 <12
05/30/03 19.61 63,000 5,400 <100 11,000 E 5,500 E 1,700 9,100 340
03/25/04 19.22 46,000 7,910 <100 10,700 E 1,670 1,110 5,440 201
10/09/06 12.41 16,700 <2,000 <1 7,700 966 1,630 5,000 303
05/04/16 14.34 6,960 1,300 <5 878 58 269 590 58
11/18/16 15.98 7,090 1,600 <20 2,150 103 474 1,170 66
06/06/18 19.39 2,530 1,400 <5 446 23 126 361 16
04/17/19 10.63 396 <1,000 <5 94 <12 23 17 <12
10/09/19 15.33 1,730 <1,000 <5 474 14 103 121 16
06/25/20 16.12 1,300 <1,000 <5 323 13 66 162 <12
01/27/22 19.66 5,510 1,100 <5 1,740 19 374 663 37
04/21/22 19.51 5,070 <1,000 <5 2,490 21 368 422 32
07/28/22 20.76 8,740 1,400 <5 4,340 27 354 446 41
10/20/22 19.77 8,520 1,200 <5 4,700 38 364 404 37
09/27/23 14.40 4,820 1,100 <5 3,400 <12 99 123 25
12/12/23 15.59 2,870 <1,000 <5 2,110 21 116 92 23
05/30/03 20.06 82,000 E 5,700 <100 21,000 E 7,400 E 730 8,200 280
10/09/06 12.38 65,100 <2,000 <5 11,200 1,570 1,520 8,780 485
05/08/07 14.52
11/12/09 15.06 41,000 10,000 <40 4,700 1,100 1,100 5,000 360
06/29/10 10.62
02/14/13 17.59 32,000 3,800 <50 8,290 271 668 3,550 227
09/10/13 15.16 20,200 2,400 <25 4,880 170 580 3,120 208
11/19/13 18.56 23,300 2,600 <10 8,140 211 814 4,000 227
07/22/14 19.76 14,100 1,800 <10 4,100 99 576 2,660 178
05/14/15 16.10 12,300 2,300 <1 2,680 51 364 2,260 137
05/03/16 14.55 19,700 4,900 <5 1,760 26 280 1,370 156
11/18/16 16.42 7,500 2,300 <100 3,580 <250 <250 900 <250
06/06/18 19.64 8,830 4,400 <5 1,700 <12 125 504 54
04/17/19 11.05 901 <1,000 <5 41 <12 <12 34 <12
10/09/19 15.73 3,110 1,700 <5 578 <12 54 143 20
06/25/20 16.43 <2,500 3,800 <100 1,910 <250 <250 350 <250
01/27/22 20.01 13,100 2,200 <5 6,690 15 178 580 57
04/21/22 19.85 14,600 2,800 <5 8,320 20 202 644 63
07/28/22 21.07 17,000 4,000 <5 10,300 17 166 577 72
10/20/22 20.12 19,900 4,100 <5 10,500 28 225 759 92
09/27/23 14.80 15,200 2,700 <5 9,330 17 167 309 34
12/12/23 15.88 11,600 2,900 <5 8,990 24 199 421 59
05/28/03 20.28 19,000 E 1,900 <20 4,300 E 2,200 E 210 1,500 41
03/24/04 19.77 29,700 E 7,310 <10 4,810 E 2,360 E 238 3,960 E 242
10/09/06 12.31 17,900 <2,000 <1 4,520 196 430 2,000 139
05/08/07 15.42 8,670 <2,000 3 4,670 116 307 1,330 133
11/12/09 15.63 18,000 1,900 6.3 9,100 140 690 2,000 210
06/29/10 11.12 15,700 5,820 3.75 6,120 126 1,430 4,700 272
02/14/13 17.79 19,100 <1000 <20 8,880 32 423 872 121
09/10/13 18.60 12,300 <1,000 <25 6,710 28 318 571 97
11/19/13 18.72 32,800 1,900 <5 16,600 47 737 1,560 186
07/22/14 19.93 18,000 1,200 <10 9,960 27 480 944 95
05/13/15 15.30 19,700 <1,000 2 10,800 24 511 938 158
05/04/16 14.71 20,300 2,600 <5 10,000 20 415 1,200 206
11/18/16 16.87 21,000 3,100 <50 12,700 <50 730 1,220 182
06/06/18 19.84 14,400 3,900 <5 5,620 24 505 676 123
04/17/19 11.34 20,600 8,300 <40 1,930 <100 1,600 4,400 423
10/09/19 16.08 21,200 5,400 <5 10,000 18 915 1,680 266
06/25/20 18.73 21,900 5,100 <50 11,900 <125 924 1,660 194
01/27/22 19.90 20,000 2,100 <5 13,800 25 544 804 135
04/21/22 19.75 19,700 2,500 <5 13,000 28 592 872 144
07/28/22 20.92 30,000 3,000 <5 20,600 33 640 848 165
10/20/22 20.04 21,300 3,100 <5 14,500 33 542 744 134
09/27/23 14.84 24,200 5,800 <5 8,850 27 1,040 2,390 170
12/12/23 15.82 25,300 5,400 <5 15,100 34 1,080 1,590 284
MW-15
MW-14
MW-16
MW-17
LNAPL
LNAPL
Page 3 of 4 Terracon Consultants
Table 2
Brent Redd Property
148 East Center Street, Monticello, UT
(Facility ID 5000003, Release Site GZQ)
Groundwater Analytical Results (g/L)
Sample
Location Sample Date
Depth to
Water
(ft-btoc)
TPH-GRO TPH-DRO MTBE Benzene Toluene Ethyl-
benzene
Total
Xylene
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 (ug/L)
TIER 1 Screening Criteria (ug/L)
05/28/03 18.49 23,000 E 2,100 <20 8,400 E 1,100 E 27 1,000 47
03/24/04 17.96 16,600 E 6,090 <10 5,410 E 545 E 94 671 120
10/09/06 10.56 5,780 <2,000 <1 243 52.7 127 893 182
05/08/07 14.09 5,270 <2,000 <1 3,270 351 323 379 107
11/12/09 14.04 2,500 720 <2 970 17.0 94 230 55
06/29/10 9.36 477 670 <2 410 <2 7.08 4.89 3.16
02/14/13 15.97 3,640 1,200 <10 834 102 393 744 164
09/10/13 16.75 4,180 1,400 <5 525 116 272 443 34
11/19/13 16.89 3,080 <1,000 <5 378 56 247 510 25
07/22/14 18.06 1,760 <1,000 <10 240 50 183 680 36
05/14/15 14.49 2,170 1,000 <1 175 33 88 276 17
05/04/16 12.95 404 <1,000 <5 12 <5 13 18 6
11/18/16 15.17 2,930 <1,000 <10 258 <25 206 168 <25
06/06/18 18.01 3,310 1,200 <5 306 35 230 381 33
04/17/19 9.19 <125 <1,000 <5 5 <12 <12 <12 <12
10/09/19 14.24 1,270 <1,000 <5 812 <12 <12 <12 16
06/25/20 14.89 <1,125 <1,000 <50 1,100 <125 <125 <125 <125
01/27/22 18.29 965 <1,100 <5 460 <12 74 42 <12
04/21/22 18.09 959 <1,000 <5 412 13 113 162 24
07/28/22 19.21 588 <1,000 <5 349 <12 44 17 <12
10/20/22 18.35 <125 <1,000 <5 115 <12 <12 <12 <12
09/27/23 13.19 <125 2,100 <5 46 <12 <12 <12 <12
12/12/23 14.14 982 2,300 <5 982 <12 <12 <12 <12
01/27/22 19.09 687 <1,000 <5 25 <12 21 43 14
04/21/22 18.89 <125 <1,000 <5 10 <12 <12 15 <12
07/28/22 20.08 <125 <1,000 <5 8 <12 <12 <12 <12
10/20/22 19.25 <125 <1,000 <5 8 <12 <12 <12 <12
09/27/23 14.12 <125 <1,000 <5 5 <12 <12 <12 <12
12/12/23 15.05 <10 <1,000 <4 0.5 <1 <1 <1 <1
01/27/22 17.27 <125 <1,000 <5 9 <12 <12 <12 <12
04/21/22 16.94 <125 <1,000 <5 9 <12 <12 <12 <12
07/28/22 17.65 <125 <1,000 <5 7 <12 <12 <12 <12
10/20/22 17.28 <125 <1,000 <5 <5 <12 <12 <12 <12
09/27/23 12.22 <125 <1,000 <5 18 <12 <12 <12 <12
12/12/23 12.69 <12 <1,000 <5 11 <12 <12 <12 <12
01/27/22 18.72 <125 <1,000 <5 <5 <12 <12 <12 <12
04/21/22 18.20 <125 <1,000 <5 <5 <12 <12 <12 <12
07/28/22 18.50 <125 <1,000 <5 <5 <12 <12 <12 <12
10/20/22 18.49 <125 <1,000 <5 <5 <12 <12 <12 <12
09/27/23 12.87 <125 <1,000 <5 <5 <12 <12 <12 <12
12/12/23 12.46 <125 <1,000 <5 <5 <12 <12 <12 <12
NOTES:
LNAPL = Light Nonaqueous Phase Liquid
Bold type indicates concentration exceeds laboratory reporting limit.
<Not detected at laboratory reporting limit.
Concentration exceeds Initial Screening Level (ISL)
concentration exceeds Tier 1 Screening Level (Tier 1 SL)
MW-20
MW-21
MW-19
MW-18
Page 4 of 4 Terracon Consultants
Appendix C
Chain of Custody and Laboratory Data Sheets