HomeMy WebLinkAboutWNC-REXBURG-ID - Drainage Report - 2024.12.02
Table of Contents
Introduction ......................................................................................................................................... 1
Project Description .............................................................................................................................. 1
Site Description .................................................................................................................................... 1
Scope and Method ............................................................................................................................... 1
Existing Drainage Conditions and Analysis .......................................................................................... 1
Design Criteria and Limits .................................................................................................................... 2
Proposed Drainage Conditions and Analysis ....................................................................................... 2
Seepage Bed ......................................................................................................................................... 3
Sand and Grease Trap .......................................................................................................................... 4
Inlet, Gutter and Pipe Capacity ............................................................................................................ 4
Additional Information ........................................................................................................................ 4
Summary .............................................................................................................................................. 4
APPENDICES
Appendix A - Figures
Vicinity Map
Post-Development Drainage Basin Exhibit
Storm Water Improvement Plans
Appendix B - Calculations
Post-Development Runoff Calculations
Seepage Bed Calculations
Sand and Grease Trap Calculations
Inlet, Gutter and Pipe Calculations
Appendix C - Geotechnical Engineering and Additional Information
Terracon Geotechnical Report (May 2024)
Terracon Geotechnical Addendum (May 2024)
USDA Custom Soil Resource Report (November 2024)
1
INTRODUCTION
The purpose of this report is to show that the storm drainage facilities for the proposed
WinCo Foods (Project) are designed to meet the requirements of the City of Rexburg, as
well as the water quality requirements of the Idaho Department of Environmental
Quality (DEQ). This report has been prepared at the request of the developer, WinCo
Foods.
PROJECT DESCRIPTION
The Project consists of a single commercial property on roughly 18.1 acres. The
proposed improvements to the site include roadways, sidewalks, lot grading as well as
site utilities including water, sewer, pressure irrigation, gravity irrigation and storm
water management improvements. Storm water from developed areas will be collected
and treated onsite.
SITE DESCRIPTION
The Project is located roughly 1,050 feet east of the intersection of Moody Road and
South side Boulevard in the City of Rexburg, Idaho. Refer to Appendix A for a Vicinity
Map of the Project. The proposed parcel consists primarily of agricultural fields with a
rough area of 18.1 acres.
SCOPE AND METHOD
The Rational Method is the standard method for small catchment areas. This method
was used to calculate the pre-development and post-development peak runoff rates
and runoff volumes. A specialized excel spreadsheet was used to calculate runoff rates
and volumes of the design storms and for sizing the drainage facilities. Autodesk
Hydroflow Express version 2021 was used to verify and size curb inlets, street flooding
capacity, pipe sizing and hydraulic capacity, but only a select number of analyzed pipes
are included in this report. Refer to Appendix B for calculations. Runoff rates and storm
volumes were established for each basin for the 25-year and 100-year storms. The
Technical Guidance on Implementing the Stormwater Runoff Requirements for Federal
Projects under Section 438 of the Energy Independence and Security Act document
provided by the Environmental Protection Agency (EPA) is generally used to determine
the peak elevation of the 0.6” storm event.
EXISTING DRAINAGE CONDITIONS AND ANALYSIS
The existing watershed for the Project includes roughly 18.1 acres of existing agricultural
land. The majority of the onsite areas include mostly undeveloped agricultural land with
Hydrologic Type “C” soils. A runoff coefficient of C=0.12 was selected for these areas,
which corresponds to pervious surfaces with average slopes (1-3%) and Type “C” Soils.
Currently, the drainage from the Project drains from the East to the West.
2
DESIGN CRITERIA AND LIMITS
The Geotechnical Report prepared by Terracon dated May 2024 states ground water is
expected to be encountered between 28.5 and 29 feet below ground surface (BGS). The
required 3 feet of separation between groundwater and the bottom of the infiltration
facilities will be maintained. Based on the types of soils found onsite, the geotechnical
report recommends a design infiltration rate of 2.5 in/hr to be used (5 in/hr achieved in
field testing with a factor of safety of 2 applied). Refer to Appendix C geotechnical
engineering and additional information for soils information.
Due to the sensitivity of the infiltration rates across the site, the geotechnical engineer
and developer may test the infiltration rate at each storm water disposal location and
provide the results to the design engineer. The design engineer will then be able to
determine if the proposed stormwater facility needs any modifications. Any redesign of
a stormwater facility shall be provided to the City engineer for review and approval.
PROPOSED DRAINAGE CONDITIONS AND ANALYSIS
The proposed drainage system improvements consist of a gutters, curb inlets, storm
pipe networks, sand & grease traps and seepage beds.
The post-development site was broken into 8 basins. The land use type and runoff
coefficients are as follows: roof areas, impervious roadways and sidewalks (C=0.95).
Each basin was delineated according to the tributary area contributing to each drainage
structure or facility, such as gutter, inlet, pipe, catch basin inlet, etc. A design point was
assigned to certain drainage structures or facilities, such as an inlet or pipe junction, and
analyzed. Refer to Appendix B for drainage basin peak flow rates.
Design Point 1 is the point of discharge for Basin A. This basin covers approximately 1.31
acres and consists of impervious areas (C=0.95). Storm water runoff includes a
combination of overland sheet flow over parking lot asphalt as well as shallow
concentrated gutter flow. Flow is intercepted by storm water inlets and directed to
Seepage Bed A.
Design Point 2 is the point of discharge for Basin B. This basin covers approximately 1.99
acres and consists of impervious areas (C=0.95). Storm water runoff includes a
combination of overland sheet flow over parking lot asphalt as well as shallow
concentrated gutter flow. Flow is intercepted by storm water inlets and directed to
Seepage Bed B.
Design Point 3 is the point of discharge for Basin C. This basin covers approximately 1.91
acres and consists of impervious areas (C=0.95). Storm water runoff includes a
combination of overland sheet flow over parking lot asphalt as well as shallow
concentrated gutter flow. Flow is intercepted by storm water inlets and directed to
Seepage Bed C.
3
Design Point 4 is the point of discharge for Basin D. This basin covers approximately 1.87
acres and consists of impervious areas (C=0.95). Storm water runoff includes a
combination of overland sheet flow over parking lot asphalt as well as shallow
concentrated gutter flow. Flow is intercepted by storm water inlets and directed to
Seepage Bed D.
Design Point 5 is the point of discharge for Basin E. This basin covers approximately 0.79
acres and consists of impervious areas (C=0.95). Storm water runoff includes a
combination of overland sheet flow over parking lot asphalt as well as shallow
concentrated gutter flow. Flow is intercepted by storm water inlets and directed to
Seepage Bed E.
Design Point 6 is the point of discharge for Basin F. This basin covers approximately 1.25
acres and consists of impervious areas (C=0.95). Storm water runoff includes a
combination of overland sheet flow over parking lot asphalt as well as shallow
concentrated gutter flow. Flow is intercepted by storm water inlets and directed to
Seepage Bed F.
Design Point 7 is the point of discharge for Basin G. This basin covers approximately 1.24
acres and consists of impervious areas (C=0.95). Storm water runoff includes a
combination of overland sheet flow over parking lot asphalt as well as shallow
concentrated gutter flow. Flow is intercepted by storm water inlets and directed to
Seepage Bed G.
Design Point 8 is the point of discharge for Basin H. This basin covers approximately 0.33
acres and consists of impervious areas (C=0.95). Storm water runoff includes a
combination of overland sheet flow over parking lot asphalt as well as shallow
concentrated gutter flow. Flow is intercepted by storm water inlets and directed to
Seepage Bed H.
SEEPAGE BED
The seepage bed shall be built per the details and keynotes shown on the civil
construction plans and per City of Rexburg Storm Water Policy Manual. The seepage
bed has been designed to hold the stormwater volume from the 100-year storm
event. The volume of seepage bed has been increased by 15% to account for
silt/sediment accumulation as the bed ages. Based on our calculations, the seepage
bed is adequately sized for the 100-year storm event with 90% of the storm event
draining in 48-hours. Refer to Appendix B seepage bed calculations for additional
information.
4
SAND AND GREASE TRAP
The proposed drainage design for the project includes sand and grease traps used as a
pre-treatment facility for the contributing portions of the post development layout
conditions. The sand and grease traps have been sized for handling at least the water
quality storm event. Please refer to Appendix B sand and grease trap calculations for
additional information.
INLET, GUTTER AND PIPE CAPACITY
The catch basin inlets will be built per the details shown on the civil construction plans.
Based on the attached calculations, the inlets have been sized to intercept the 100-year
peak flow. Refer to Appendix B for inlet, gutter and pipe calculations for additional
information.
The gutter capacity of the proposed roadways was verified to ensure that overtopping
of the curb would not occur in the 25-year and 100-year storm event. Refer to Appendix
B for inlet, gutter and pipe calculations for additional information.
The storm pipes have been sized to convey the 25-year and 100-year peak flow rates.
ADDITIONAL INFORMATION
At this time, no permits or discharge agreements are expected to be required.
SUMMARY
This report outlines that the design, sizing and analysis of the Project storm water
system conforms to City of Rexburg and DEQ storm water design criteria.
APPENDIX A - FIGURES
CIVIL ENGINEERING
B
WA BLAINE A. WOMER
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M
M
M
M
M
M
MM
S DS D S D S D
S DS DS DS D
S
S D
S D
S D
NO PARKING NO PARKING NO PARKING
NO PARKINGNO PARKINGNO PARKING
S
S DS DS D
E. MOODY ROAD
CI
V
I
L
E
N
G
I
N
E
E
R
I
N
G
B WA
BL
A
I
N
E
A
.
W
O
M
E
R
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CI
V
I
L
E
N
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I
N
E
E
R
I
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G
B WA
BL
A
I
N
E
A
.
W
O
M
E
R
●
SHEET NOTES
KEYNOTES
CI
V
I
L
E
N
G
I
N
E
E
R
I
N
G
B WA
BL
A
I
N
E
A
.
W
O
M
E
R
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SHEET NOTES
KEYNOTES
CI
V
I
L
E
N
G
I
N
E
E
R
I
N
G
B WA
BL
A
I
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E
A
.
W
O
M
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R
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SHEET NOTES
KEYNOTES
APPENDIX B - CALCULATIONS
POST-DEVELOPMENT RUNOFF CALCULATIONS
Catchment A WinCo Foods Rexburg
Project No. W2024005
Rational Method (TR-55)
Elev. 1 Elev. 2 Lgutter Intercept Slope (Sp)Vgutter Tc-gutter
(ft)(ft)(ft)Coeff. (k)(%)(fps)(min)
A 0 6.00 250 0.619 2.40 3.15 1.32
Total Tc
n L P2 s Tc-sheet Tc C1 Area1 C2 Area2 CT AreaT
(unitless)(ft)(in)(ft/ft)(min)(min)(ac)(ac)(ac)
A 0.24 0 1.2 0.02 10.0 0.95 1.31 0.95 1.31
Total Area 1.31
Comp. C 0.95
i2 i25 i50 i100 Q2 Q25 Q50 Q100
(in/hr)(in/hr)(in/hr)(in/hr)(cfs)(cfs)(cfs)(cfs)
A 1.25 3.00 3.50 4.10 1.56 3.73 4.36 5.10
1.56 3.73 4.36 5.10
Gutter Flow
Sub-
catchment
Sub-
catchment
Sub-
catchment
Sheet Flow Calculation Catchment Parameters
Design Storm Intensities Design Storm Flow Rates Soil Parameters
Infil. Rate
(F)2.50 in/hr
𝑇𝑇𝑐𝑐=𝑇𝑇𝑐𝑐−𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔+𝑇𝑇𝑐𝑐−𝑠𝑠𝑠𝑔𝑔𝑔𝑔𝑔𝑔
𝑇𝑇𝑐𝑐−𝑠𝑠𝑠𝑔𝑔𝑔𝑔𝑔𝑔=0.007 𝑛𝑛𝑛𝑛0.8𝑃𝑃2 0.5 𝑠𝑠0.4𝑉𝑉𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔= 3.281𝑘𝑘𝑆𝑆𝑝𝑝0.5
𝑇𝑇𝑐𝑐−𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔=𝑛𝑛𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔60 ⋅ 𝑉𝑉𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔
𝑄𝑄=𝐶𝐶𝐶𝐶𝐶𝐶
V. 2018-10-15 30 Sep 2024
Catchment B WinCo Foods Rexburg
Project No. W2024005
Rational Method (TR-55)
Elev. 1 Elev. 2 Lgutter Intercept Slope (Sp)Vgutter Tc-gutter
(ft)(ft)(ft)Coeff. (k)(%)(fps)(min)
B 0 6.00 250 0.619 2.40 3.15 1.32
Total Tc
n L P2 s Tc-sheet Tc C1 Area1 C2 Area2 CT AreaT
(unitless)(ft)(in)(ft/ft)(min)(min)(ac)(ac)(ac)
B 0.24 0 1.2 0.02 10.0 0.95 1.99 0.95 1.99
Total Area 1.99
Comp. C 0.95
i2 i25 i50 i100 Q2 Q25 Q50 Q100
(in/hr)(in/hr)(in/hr)(in/hr)(cfs)(cfs)(cfs)(cfs)
B 1.25 3.00 3.50 4.10 2.36 5.67 6.62 7.75
2.36 5.67 6.62 7.75
Gutter Flow
Sub-
catchment
Sub-
catchment
Sub-
catchment
Sheet Flow Calculation Catchment Parameters
Design Storm Intensities Design Storm Flow Rates Soil Parameters
Infil. Rate
(F)2.50 in/hr
𝑇𝑇𝑐𝑐=𝑇𝑇𝑐𝑐−𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔+𝑇𝑇𝑐𝑐−𝑠𝑠𝑠𝑔𝑔𝑔𝑔𝑔𝑔
𝑇𝑇𝑐𝑐−𝑠𝑠𝑠𝑔𝑔𝑔𝑔𝑔𝑔=0.007 𝑛𝑛𝑛𝑛0.8𝑃𝑃2 0.5 𝑠𝑠0.4𝑉𝑉𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔= 3.281𝑘𝑘𝑆𝑆𝑝𝑝0.5
𝑇𝑇𝑐𝑐−𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔=𝑛𝑛𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔60 ⋅ 𝑉𝑉𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔
𝑄𝑄=𝐶𝐶𝑖𝑖𝐴𝐴
V. 2018-10-15 30 Sep 2024
Catchment C WinCo Foods Rexburg
Project No. W2024005
Rational Method (TR-55)
Elev. 1 Elev. 2 Lgutter Intercept Slope (Sp)Vgutter Tc-gutter
(ft)(ft)(ft)Coeff. (k)(%)(fps)(min)
C 0 6.00 250 0.619 2.40 3.15 1.32
Total Tc
n L P2 s Tc-sheet Tc C1 Area1 C2 Area2 CT AreaT
(unitless)(ft)(in)(ft/ft)(min)(min)(ac)(ac)(ac)
C 0.24 0 1.2 0.02 10.0 0.95 1.91 0.95 1.91
Total Area 1.91
Comp. C 0.95
i2 i25 i50 i100 Q2 Q25 Q50 Q100
(in/hr)(in/hr)(in/hr)(in/hr)(cfs)(cfs)(cfs)(cfs)
C 1.25 3.00 3.50 4.10 2.27 5.44 6.35 7.44
2.27 5.44 6.35 7.44
Gutter Flow
Sub-
catchment
Sub-
catchment
Sub-
catchment
Sheet Flow Calculation Catchment Parameters
Design Storm Intensities Design Storm Flow Rates Soil Parameters
Infil. Rate
(F)2.50 in/hr
𝑇𝑇𝑐𝑐=𝑇𝑇𝑐𝑐−𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔+𝑇𝑇𝑐𝑐−𝑠𝑠𝑠𝑔𝑔𝑔𝑔𝑔𝑔
𝑇𝑇𝑐𝑐−𝑠𝑠𝑠𝑔𝑔𝑔𝑔𝑔𝑔=0.007 𝑛𝑛𝑛𝑛0.8𝑃𝑃2 0.5 𝑠𝑠0.4𝑉𝑉𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔= 3.281𝑘𝑘𝑆𝑆𝑝𝑝0.5
𝑇𝑇𝑐𝑐−𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔=𝑛𝑛𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔60 ⋅ 𝑉𝑉𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔
𝑄𝑄=𝐶𝐶𝑖𝑖𝐴𝐴
V. 2018-10-15 30 Sep 2024
Catchment D WinCo Foods Rexburg
Project No. W2024005
Rational Method (TR-55)
Elev. 1 Elev. 2 Lgutter Intercept Slope (Sp)Vgutter Tc-gutter
(ft)(ft)(ft)Coeff. (k)(%)(fps)(min)
D 0 6.00 250 0.619 2.40 3.15 1.32
Total Tc
n L P2 s Tc-sheet Tc C1 Area1 C2 Area2 CT AreaT
(unitless)(ft)(in)(ft/ft)(min)(min)(ac)(ac)(ac)
D 0.24 0 1.2 0.02 10.0 0.95 1.87 0.95 1.87
Total Area 1.87
Comp. C 0.95
i2 i25 i50 i100 Q2 Q25 Q50 Q100
(in/hr)(in/hr)(in/hr)(in/hr)(cfs)(cfs)(cfs)(cfs)
D 1.25 3.00 3.50 4.10 2.22 5.33 6.22 7.28
2.22 5.33 6.22 7.28
Gutter Flow
Sub-
catchment
Sub-
catchment
Sub-
catchment
Sheet Flow Calculation Catchment Parameters
Design Storm Intensities Design Storm Flow Rates Soil Parameters
Infil. Rate
(F)2.50 in/hr
𝑇𝑇𝑐𝑐=𝑇𝑇𝑐𝑐−𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔+𝑇𝑇𝑐𝑐−𝑠𝑠𝑠𝑔𝑔𝑔𝑔𝑔𝑔
𝑇𝑇𝑐𝑐−𝑠𝑠𝑠𝑔𝑔𝑔𝑔𝑔𝑔=0.007 𝑛𝑛𝑛𝑛0.8𝑃𝑃2 0.5 𝑠𝑠0.4𝑉𝑉𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔= 3.281𝑘𝑘𝑆𝑆𝑝𝑝0.5
𝑇𝑇𝑐𝑐−𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔=𝑛𝑛𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔60 ⋅ 𝑉𝑉𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔
𝑄𝑄=𝐶𝐶𝑖𝑖𝐴𝐴
V. 2018-10-15 30 Sep 2024
Catchment E WinCo Foods Rexburg
Project No. W2024005
Rational Method (TR-55)
Elev. 1 Elev. 2 Lgutter Intercept Slope (Sp)Vgutter Tc-gutter
(ft)(ft)(ft)Coeff. (k)(%)(fps)(min)
E 0 6.00 250 0.619 2.40 3.15 1.32
Total Tc
n L P2 s Tc-sheet Tc C1 Area1 C2 Area2 CT AreaT
(unitless)(ft)(in)(ft/ft)(min)(min)(ac)(ac)(ac)
E 0.24 0 1.2 0.02 10.0 0.95 0.79 0.95 0.79
Total Area 0.79
Comp. C 0.95
i2 i25 i50 i100 Q2 Q25 Q50 Q100
(in/hr)(in/hr)(in/hr)(in/hr)(cfs)(cfs)(cfs)(cfs)
E 1.25 3.00 3.50 4.10 0.94 2.25 2.63 3.08
0.94 2.25 2.63 3.08
Gutter Flow
Sub-
catchment
Sub-
catchment
Sub-
catchment
Sheet Flow Calculation Catchment Parameters
Design Storm Intensities Design Storm Flow Rates Soil Parameters
Infil. Rate
(F)2.50 in/hr
𝑇𝑇𝑐𝑐=𝑇𝑇𝑐𝑐−𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔+𝑇𝑇𝑐𝑐−𝑠𝑠𝑠𝑔𝑔𝑔𝑔𝑔𝑔
𝑇𝑇𝑐𝑐−𝑠𝑠𝑠𝑔𝑔𝑔𝑔𝑔𝑔=0.007 𝑛𝑛𝑛𝑛0.8𝑃𝑃2 0.5 𝑠𝑠0.4𝑉𝑉𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔= 3.281𝑘𝑘𝑆𝑆𝑝𝑝0.5
𝑇𝑇𝑐𝑐−𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔=𝑛𝑛𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔60 ⋅ 𝑉𝑉𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔
𝑄𝑄=𝐶𝐶𝐶𝐶𝐶𝐶
V. 2018-10-15 30 Sep 2024
Catchment F WinCo Foods Rexburg
Project No. W2024005
Rational Method (TR-55)
Elev. 1 Elev. 2 Lgutter Intercept Slope (Sp)Vgutter Tc-gutter
(ft)(ft)(ft)Coeff. (k)(%)(fps)(min)
F 0 6.00 250 0.619 2.40 3.15 1.32
Total Tc
n L P2 s Tc-sheet Tc C1 Area1 C2 Area2 CT AreaT
(unitless)(ft)(in)(ft/ft)(min)(min)(ac)(ac)(ac)
F 0.24 0 1.2 0.02 10.0 0.95 1.25 0.95 1.25
Total Area 1.25
Comp. C 0.95
i2 i25 i50 i100 Q2 Q25 Q50 Q100
(in/hr)(in/hr)(in/hr)(in/hr)(cfs)(cfs)(cfs)(cfs)
F 1.25 3.00 3.50 4.10 1.48 3.56 4.16 4.87
1.48 3.56 4.16 4.87
Gutter Flow
Sub-
catchment
Sub-
catchment
Sub-
catchment
Sheet Flow Calculation Catchment Parameters
Design Storm Intensities Design Storm Flow Rates Soil Parameters
Infil. Rate
(F)2.50 in/hr
𝑇𝑇𝑐𝑐=𝑇𝑇𝑐𝑐−𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔+𝑇𝑇𝑐𝑐−𝑠𝑠𝑠𝑔𝑔𝑔𝑔𝑔𝑔
𝑇𝑇𝑐𝑐−𝑠𝑠𝑠𝑔𝑔𝑔𝑔𝑔𝑔=0.007 𝑛𝑛𝑛𝑛0.8𝑃𝑃2 0.5 𝑠𝑠0.4𝑉𝑉𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔= 3.281𝑘𝑘𝑆𝑆𝑝𝑝0.5
𝑇𝑇𝑐𝑐−𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔=𝑛𝑛𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔60 ⋅ 𝑉𝑉𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔
𝑄𝑄=𝐶𝐶𝐶𝐶𝐶𝐶
V. 2018-10-15 30 Sep 2024
Catchment G WinCo Foods Rexburg
Project No. W2024005
Rational Method (TR-55)
Elev. 1 Elev. 2 Lgutter Intercept Slope (Sp)Vgutter Tc-gutter
(ft)(ft)(ft)Coeff. (k)(%)(fps)(min)
G 0 6.00 250 0.619 2.40 3.15 1.32
Total Tc
n L P2 s Tc-sheet Tc C1 Area1 C2 Area2 CT AreaT
(unitless)(ft)(in)(ft/ft)(min)(min)(ac)(ac)(ac)
G 0.24 0 1.2 0.02 10.0 0.95 1.24 0.95 1.24
Total Area 1.24
Comp. C 0.95
i2 i25 i50 i100 Q2 Q25 Q50 Q100
(in/hr)(in/hr)(in/hr)(in/hr)(cfs)(cfs)(cfs)(cfs)
G 1.25 3.00 3.50 4.10 1.47 3.53 4.12 4.83
1.47 3.53 4.12 4.83
Gutter Flow
Sub-
catchment
Sub-
catchment
Sub-
catchment
Sheet Flow Calculation Catchment Parameters
Design Storm Intensities Design Storm Flow Rates Soil Parameters
Infil. Rate
(F)2.50 in/hr
𝑇𝑇𝑐𝑐=𝑇𝑇𝑐𝑐−𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔+𝑇𝑇𝑐𝑐−𝑠𝑠𝑠𝑔𝑔𝑔𝑔𝑔𝑔
𝑇𝑇𝑐𝑐−𝑠𝑠𝑠𝑔𝑔𝑔𝑔𝑔𝑔=0.007 𝑛𝑛𝑛𝑛0.8𝑃𝑃2 0.5 𝑠𝑠0.4𝑉𝑉𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔= 3.281𝑘𝑘𝑆𝑆𝑝𝑝0.5
𝑇𝑇𝑐𝑐−𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔=𝑛𝑛𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔60 ⋅ 𝑉𝑉𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔
𝑄𝑄=𝐶𝐶𝑖𝑖𝐴𝐴
V. 2018-10-15 30 Sep 2024
Catchment H WinCo Foods Rexburg
Project No. W2024005
Rational Method (TR-55)
Elev. 1 Elev. 2 Lgutter Intercept Slope (Sp)Vgutter Tc-gutter
(ft)(ft)(ft)Coeff. (k)(%)(fps)(min)
H 0 6.00 250 0.619 2.40 3.15 1.32
Total Tc
n L P2 s Tc-sheet Tc C1 Area1 C2 Area2 CT AreaT
(unitless)(ft)(in)(ft/ft)(min)(min)(ac)(ac)(ac)
H 0.24 0 1.2 0.02 10.0 0.95 0.33 0.95 0.33
Total Area 0.33
Comp. C 0.95
i2 i25 i50 i100 Q2 Q25 Q50 Q100
(in/hr)(in/hr)(in/hr)(in/hr)(cfs)(cfs)(cfs)(cfs)
H 1.25 3.00 3.50 4.10 0.39 0.94 1.10 1.29
0.39 0.94 1.10 1.29
Gutter Flow
Sub-
catchment
Sub-
catchment
Sub-
catchment
Sheet Flow Calculation Catchment Parameters
Design Storm Intensities Design Storm Flow Rates Soil Parameters
Infil. Rate
(F)2.50 in/hr
𝑇𝑇𝑐𝑐=𝑇𝑇𝑐𝑐−𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔+𝑇𝑇𝑐𝑐−𝑠𝑠𝑠𝑔𝑔𝑔𝑔𝑔𝑔
𝑇𝑇𝑐𝑐−𝑠𝑠𝑠𝑔𝑔𝑔𝑔𝑔𝑔=0.007 𝑛𝑛𝑛𝑛0.8𝑃𝑃2 0.5 𝑠𝑠0.4𝑉𝑉𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔= 3.281𝑘𝑘𝑆𝑆𝑝𝑝0.5
𝑇𝑇𝑐𝑐−𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔=𝑛𝑛𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔60 ⋅ 𝑉𝑉𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔
𝑄𝑄=𝐶𝐶𝑖𝑖𝐴𝐴
V. 2018-10-15 30 Sep 2024
SEEPAGE BED CALCULATIONS
Catchment A WinCo Foods Rexburg
Project No. W2024005
Seepage Bed
Design Storm frequency 100 -year
Design Storm duration 60 -minutes
Sedimentation factor (f)15 %
Soil Infiltration rate (rF)2.50 in/hr
Weighted Runoff Coefficient (C)0.95
Design Storm Inentsity (iStor-100)1.25 in/hr
Catchment Area (A)1.31 ac
Required Storage Volume (V100)6,441 ft3
Volume
Length (LT) =101 ft
Width =15 ft
Depth =10 ft Account for 1st hr of infiltration?Yes
Void Ratio =40 %
18" pipe (No. in bed) =1 18" pipe volume =177 ft3
12" pipe (No. in bed) =0 12" pipe volume =0 ft3
Rock volume = 14,973 ft3 Rock void volume =5,989 ft3
Bed Infiltration Area (AF) =1,515 ft2
Bed infiltration Rate (RF) =315.63 ft3/hr
Adjusted V100 (AAdj) =6,125 ft3 Bed 1st hr infiltration volume (VF) =316 ft3
Avail Bed Vol (VA) =6,166 ft3 Time for 90% Infiltration (t90%) =18.37 hr
Checks:VA > Vadj PASS
t90% < 48 PASS
Multiple Sub-Beds
Sub-Bed ID Length
SB-B1 ft LMax =393 ft
SB-B2 ft 400' between manholes
Total Length (∑LSub)=ft 7' from bed to manhole center
Checks:∑LSub = LT
LSub < LMax
Equations:
𝑉𝑉=𝐶𝐶 ∗𝐶𝐶∗𝐶𝐶∗3600 ∗(1 +𝑓𝑓)
𝐶𝐶𝐹𝐹= 2 𝑙𝑙+𝑤𝑤 ⋅𝑑𝑑𝑉𝑉100 =C ⋅𝐶𝐶⋅𝐶𝐶⋅1 +𝑓𝑓∗3600
𝑅𝑅𝐹𝐹=𝐶𝐶𝐹𝐹⋅𝑟𝑟𝐹𝐹12𝑡𝑡90%=0.9 ⋅𝑉𝑉100𝑅𝑅𝐹𝐹
V. 2018-10-15 30 Sep 2024
Catchment B WinCo Foods Rexburg
Project No. W2024005
Seepage Bed
Design Storm frequency 100 -year
Design Storm duration 60 -minutes
Sedimentation factor (f)15 %
Soil Infiltration rate (rF)2.50 in/hr
Weighted Runoff Coefficient (C)0.95
Design Storm Inentsity (iStor-100)1.25 in/hr
Catchment Area (A)1.99 ac
Required Storage Volume (V100)9,784 ft3
Volume
Length (LT) =153 ft
Width =15 ft
Depth =10 ft Account for 1st hr of infiltration?Yes
Void Ratio =40 %
18" pipe (No. in bed) =1 18" pipe volume =269 ft3
12" pipe (No. in bed) =0 12" pipe volume =0 ft3
Rock volume = 22,681 ft3 Rock void volume =9,073 ft3
Bed Infiltration Area (AF) =2,295 ft2
Bed infiltration Rate (RF) =478.13 ft3/hr
Adjusted V100 (AAdj) =9,306 ft3 Bed 1st hr infiltration volume (VF) =478 ft3
Avail Bed Vol (VA) =9,341 ft3 Time for 90% Infiltration (t90%) =18.42 hr
Checks:VA > Vadj PASS
t90% < 48 PASS
Multiple Sub-Beds
Sub-Bed ID Length
SB-B1 ft LMax =393 ft
SB-B2 ft 400' between manholes
Total Length (∑LSub)=ft 7' from bed to manhole center
Checks:∑LSub = LT
LSub < LMax
Equations:
𝑉𝑉=𝐶𝐶 ∗ 𝑖𝑖 ∗ 𝐴𝐴 ∗3600 ∗(1 +𝑓𝑓)
𝐴𝐴𝐹𝐹= 2 𝑙𝑙+𝑤𝑤 ⋅𝑑𝑑𝑉𝑉100 =C ⋅𝑖𝑖⋅𝐴𝐴⋅1 +𝑓𝑓∗3600
𝑅𝑅𝐹𝐹=𝐴𝐴𝐹𝐹⋅𝑟𝑟𝐹𝐹12𝑡𝑡90%=0.9 ⋅𝑉𝑉100𝑅𝑅𝐹𝐹
V. 2018-10-15 30 Sep 2024
Catchment C WinCo Foods Rexburg
Project No. W2024005
Seepage Bed
Design Storm frequency 100 -year
Design Storm duration 60 -minutes
Sedimentation factor (f)15 %
Soil Infiltration rate (rF)2.50 in/hr
Weighted Runoff Coefficient (C)0.95
Design Storm Inentsity (iStor-100)1.25 in/hr
Catchment Area (A)1.91 ac
Required Storage Volume (V100)9,391 ft3
Volume
Length (LT) =147 ft
Width =15 ft
Depth =10 ft Account for 1st hr of infiltration?Yes
Void Ratio =40 %
18" pipe (No. in bed) =1 18" pipe volume =258 ft3
12" pipe (No. in bed) =0 12" pipe volume =0 ft3
Rock volume = 21,792 ft3 Rock void volume =8,717 ft3
Bed Infiltration Area (AF) =2,205 ft2
Bed infiltration Rate (RF) =459.38 ft3/hr
Adjusted V100 (AAdj) =8,932 ft3 Bed 1st hr infiltration volume (VF) =459 ft3
Avail Bed Vol (VA) =8,975 ft3 Time for 90% Infiltration (t90%) =18.40 hr
Checks:VA > Vadj PASS
t90% < 48 PASS
Multiple Sub-Beds
Sub-Bed ID Length
SB-B1 ft LMax =393 ft
SB-B2 ft 400' between manholes
Total Length (∑LSub)=ft 7' from bed to manhole center
Checks:∑LSub = LT
LSub < LMax
Equations:
𝑉𝑉=𝐶𝐶 ∗ 𝑖𝑖 ∗ 𝐴𝐴 ∗3600 ∗(1 +𝑓𝑓)
𝐴𝐴𝐹𝐹= 2 𝑙𝑙+𝑤𝑤 ⋅𝑑𝑑𝑉𝑉100 =C ⋅𝑖𝑖⋅𝐴𝐴⋅1 +𝑓𝑓∗3600
𝑅𝑅𝐹𝐹=𝐴𝐴𝐹𝐹⋅𝑟𝑟𝐹𝐹12𝑡𝑡90%=0.9 ⋅𝑉𝑉100𝑅𝑅𝐹𝐹
V. 2018-10-15 30 Sep 2024
Catchment D WinCo Foods Rexburg
Project No. W2024005
Seepage Bed
Design Storm frequency 100 -year
Design Storm duration 60 -minutes
Sedimentation factor (f)15 %
Soil Infiltration rate (rF)2.50 in/hr
Weighted Runoff Coefficient (C)0.95
Design Storm Inentsity (iStor-100)1.25 in/hr
Catchment Area (A)1.87 ac
Required Storage Volume (V100)9,194 ft3
Volume
Length (LT) =144 ft
Width =15 ft
Depth =10 ft Account for 1st hr of infiltration?Yes
Void Ratio =40 %
18" pipe (No. in bed) =1 18" pipe volume =253 ft3
12" pipe (No. in bed) =0 12" pipe volume =0 ft3
Rock volume = 21,347 ft3 Rock void volume =8,539 ft3
Bed Infiltration Area (AF) =2,160 ft2
Bed infiltration Rate (RF) =450.00 ft3/hr
Adjusted V100 (AAdj) =8,744 ft3 Bed 1st hr infiltration volume (VF) =450 ft3
Avail Bed Vol (VA) =8,792 ft3 Time for 90% Infiltration (t90%) =18.39 hr
Checks:VA > Vadj PASS
t90% < 48 PASS
Multiple Sub-Beds
Sub-Bed ID Length
SB-B1 ft LMax =393 ft
SB-B2 ft 400' between manholes
Total Length (∑LSub)=ft 7' from bed to manhole center
Checks:∑LSub = LT
LSub < LMax
Equations:
𝑉𝑉=𝐶𝐶 ∗ 𝑖𝑖 ∗ 𝐴𝐴 ∗3600 ∗(1 +𝑓𝑓)
𝐴𝐴𝐹𝐹= 2 𝑙𝑙+𝑤𝑤 ⋅𝑑𝑑𝑉𝑉100 =C ⋅𝑖𝑖⋅𝐴𝐴⋅1 +𝑓𝑓∗3600
𝑅𝑅𝐹𝐹=𝐴𝐴𝐹𝐹⋅𝑟𝑟𝐹𝐹12𝑡𝑡90%=0.9 ⋅𝑉𝑉100𝑅𝑅𝐹𝐹
V. 2018-10-15 30 Sep 2024
Catchment E WinCo Foods Rexburg
Project No. W2024005
Seepage Bed
Design Storm frequency 100 -year
Design Storm duration 60 -minutes
Sedimentation factor (f)15 %
Soil Infiltration rate (rF)2.50 in/hr
Weighted Runoff Coefficient (C)0.95
Design Storm Inentsity (iStor-100)1.25 in/hr
Catchment Area (A)0.79 ac
Required Storage Volume (V100)3,884 ft3
Volume
Length (LT) =61 ft
Width =15 ft
Depth =10 ft Account for 1st hr of infiltration?Yes
Void Ratio =40 %
18" pipe (No. in bed) =1 18" pipe volume =106 ft3
12" pipe (No. in bed) =0 12" pipe volume =0 ft3
Rock volume = 9,044 ft3 Rock void volume =3,618 ft3
Bed Infiltration Area (AF) =915 ft2
Bed infiltration Rate (RF) =190.63 ft3/hr
Adjusted V100 (AAdj) =3,693 ft3 Bed 1st hr infiltration volume (VF) =191 ft3
Avail Bed Vol (VA) =3,724 ft3 Time for 90% Infiltration (t90%) =18.34 hr
Checks:VA > Vadj PASS
t90% < 48 PASS
Multiple Sub-Beds
Sub-Bed ID Length
SB-B1 ft LMax =393 ft
SB-B2 ft 400' between manholes
Total Length (∑LSub)=ft 7' from bed to manhole center
Checks:∑LSub = LT
LSub < LMax
Equations:
𝑉𝑉=𝐶𝐶 ∗𝐶𝐶∗𝐶𝐶∗3600 ∗(1 +𝑓𝑓)
𝐶𝐶𝐹𝐹= 2 𝑙𝑙+𝑤𝑤 ⋅𝑑𝑑𝑉𝑉100 =C ⋅𝐶𝐶⋅𝐶𝐶⋅1 +𝑓𝑓∗3600
𝑅𝑅𝐹𝐹=𝐶𝐶𝐹𝐹⋅𝑟𝑟𝐹𝐹12𝑡𝑡90%=0.9 ⋅𝑉𝑉100𝑅𝑅𝐹𝐹
V. 2018-10-15 30 Sep 2024
Catchment F WinCo Foods Rexburg
Project No. W2024005
Seepage Bed
Design Storm frequency 100 -year
Design Storm duration 60 -minutes
Sedimentation factor (f)15 %
Soil Infiltration rate (rF)2.50 in/hr
Weighted Runoff Coefficient (C)0.95
Design Storm Inentsity (iStor-100)1.25 in/hr
Catchment Area (A)1.25 ac
Required Storage Volume (V100)6,146 ft3
Volume
Length (LT) =96 ft
Width =15 ft
Depth =10 ft Account for 1st hr of infiltration?Yes
Void Ratio =40 %
18" pipe (No. in bed) =1 18" pipe volume =168 ft3
12" pipe (No. in bed) =0 12" pipe volume =0 ft3
Rock volume = 14,232 ft3 Rock void volume =5,693 ft3
Bed Infiltration Area (AF) =1,440 ft2
Bed infiltration Rate (RF) =300.00 ft3/hr
Adjusted V100 (AAdj) =5,846 ft3 Bed 1st hr infiltration volume (VF) =300 ft3
Avail Bed Vol (VA) =5,861 ft3 Time for 90% Infiltration (t90%) =18.44 hr
Checks:VA > Vadj PASS
t90% < 48 PASS
Multiple Sub-Beds
Sub-Bed ID Length
SB-B1 ft LMax =393 ft
SB-B2 ft 400' between manholes
Total Length (∑LSub)=ft 7' from bed to manhole center
Checks:∑LSub = LT
LSub < LMax
Equations:
𝑉𝑉=𝐶𝐶 ∗𝐶𝐶∗𝐶𝐶∗3600 ∗(1 +𝑓𝑓)
𝐶𝐶𝐹𝐹= 2 𝑙𝑙+𝑤𝑤 ⋅𝑑𝑑𝑉𝑉100 =C ⋅𝐶𝐶⋅𝐶𝐶⋅1 +𝑓𝑓∗3600
𝑅𝑅𝐹𝐹=𝐶𝐶𝐹𝐹⋅𝑟𝑟𝐹𝐹12𝑡𝑡90%=0.9 ⋅𝑉𝑉100𝑅𝑅𝐹𝐹
V. 2018-10-15 30 Sep 2024
Catchment G WinCo Foods Rexburg
Project No. W2024005
Seepage Bed
Design Storm frequency 100 -year
Design Storm duration 60 -minutes
Sedimentation factor (f)15 %
Soil Infiltration rate (rF)2.50 in/hr
Weighted Runoff Coefficient (C)0.95
Design Storm Inentsity (iStor-100)1.25 in/hr
Catchment Area (A)1.24 ac
Required Storage Volume (V100)6,097 ft3
Volume
Length (LT) =96 ft
Width =15 ft
Depth =10 ft Account for 1st hr of infiltration?Yes
Void Ratio =40 %
18" pipe (No. in bed) =1 18" pipe volume =168 ft3
12" pipe (No. in bed) =0 12" pipe volume =0 ft3
Rock volume = 14,232 ft3 Rock void volume =5,693 ft3
Bed Infiltration Area (AF) =1,440 ft2
Bed infiltration Rate (RF) =300.00 ft3/hr
Adjusted V100 (AAdj) =5,797 ft3 Bed 1st hr infiltration volume (VF) =300 ft3
Avail Bed Vol (VA) =5,861 ft3 Time for 90% Infiltration (t90%) =18.29 hr
Checks:VA > Vadj PASS
t90% < 48 PASS
Multiple Sub-Beds
Sub-Bed ID Length
SB-B1 ft LMax =393 ft
SB-B2 ft 400' between manholes
Total Length (∑LSub)=ft 7' from bed to manhole center
Checks:∑LSub = LT
LSub < LMax
Equations:
𝑉𝑉=𝐶𝐶 ∗ 𝑖𝑖 ∗ 𝐴𝐴 ∗3600 ∗(1 +𝑓𝑓)
𝐴𝐴𝐹𝐹= 2 𝑙𝑙+𝑤𝑤 ⋅𝑑𝑑𝑉𝑉100 =C ⋅𝑖𝑖⋅𝐴𝐴⋅1 +𝑓𝑓∗3600
𝑅𝑅𝐹𝐹=𝐴𝐴𝐹𝐹⋅𝑟𝑟𝐹𝐹12𝑡𝑡90%=0.9 ⋅𝑉𝑉100𝑅𝑅𝐹𝐹
V. 2018-10-15 30 Sep 2024
Catchment H WinCo Foods Rexburg
Project No. W2024005
Seepage Bed
Design Storm frequency 100 -year
Design Storm duration 60 -minutes
Sedimentation factor (f)15 %
Soil Infiltration rate (rF)2.50 in/hr
Weighted Runoff Coefficient (C)0.95
Design Storm Inentsity (iStor-100)1.25 in/hr
Catchment Area (A)0.33 ac
Required Storage Volume (V100)1,623 ft3
Volume
Length (LT) =60 ft
Width =10 ft
Depth =6 ft Account for 1st hr of infiltration?Yes
Void Ratio =40 %
18" pipe (No. in bed) =1 18" pipe volume =104 ft3
12" pipe (No. in bed) =0 12" pipe volume =0 ft3
Rock volume = 3,496 ft3 Rock void volume =1,398 ft3
Bed Infiltration Area (AF) =600 ft2
Bed infiltration Rate (RF) =125.00 ft3/hr
Adjusted V100 (AAdj) =1,498 ft3 Bed 1st hr infiltration volume (VF) =125 ft3
Avail Bed Vol (VA) =1,503 ft3 Time for 90% Infiltration (t90%) =11.69 hr
Checks:VA > Vadj PASS
t90% < 48 PASS
Multiple Sub-Beds
Sub-Bed ID Length
SB-B1 ft LMax =393 ft
SB-B2 ft 400' between manholes
Total Length (∑LSub)=ft 7' from bed to manhole center
Checks:∑LSub = LT
LSub < LMax
Equations:
𝑉𝑉=𝐶𝐶 ∗ 𝑖𝑖 ∗ 𝐴𝐴 ∗3600 ∗(1 +𝑓𝑓)
𝐴𝐴𝐹𝐹= 2 𝑙𝑙+𝑤𝑤 ⋅𝑑𝑑𝑉𝑉100 =C ⋅𝑖𝑖⋅𝐴𝐴⋅1 +𝑓𝑓∗3600
𝑅𝑅𝐹𝐹=𝐴𝐴𝐹𝐹⋅𝑟𝑟𝐹𝐹12𝑡𝑡90%=0.9 ⋅𝑉𝑉100𝑅𝑅𝐹𝐹
V. 2018-10-15 30 Sep 2024
SAND AND GREASE TRAP CALCULATIONS
Catchment A WinCo Foods Rexburg
Project No. W2024005
Sand and Grease Trap
Peak Flow Design Storm 100 -year
Water Quality Design Storm 100
Peak Flow Rate (QPeak)5.10 cfs
Water Quality Flow Rate (QWQ)5.10 cfs
Design Calculations
Vault Size =1000 gallon Peak Throat Velocity (vPeak) =0.38
No. of S&G Traps =2 WQ Throat Velocity (vWQ) =0.38 fps
Baffle Spacing =20 inch
Throat Width =48 inch Allowed Max Flow rate (QMax,A) =3.33 cfs/vault
Total Throat Area =13.33 ft2 Max Flow rate (QMax) =2.55 cfs/vault
Bypass Flow Rate =0 cfs/vault
Checks:VWQ < 0.5 PASS
Bypass Required FALSE
El. Out El. In
2,505.02 2,505.37
Inlet Baffel Wall El.Outlet Baffel Wall El.
2,504.772,505.27
𝑄𝑄𝑊𝑊𝑊𝑊=𝐶𝐶 ∗𝐶𝐶𝑊𝑊𝑊𝑊∗𝐶𝐶
V. 2018-10-15 30 Sep 2024
Catchment B WinCo Foods Rexburg
Project No. W2024005
Sand and Grease Trap
Peak Flow Design Storm 100 -year
Water Quality Design Storm 100
Peak Flow Rate (QPeak)7.75 cfs
Water Quality Flow Rate (QWQ)7.75 cfs
Design Calculations
Vault Size =1500 gallon Peak Throat Velocity (vPeak) =0.47
No. of S&G Traps =2 WQ Throat Velocity (vWQ) =0.47 fps
Baffle Spacing =20 inch
Throat Width =60 inch Allowed Max Flow rate (QMax,A) =4.15 cfs/vault
Total Throat Area =16.67 ft2 Max Flow rate (QMax) =3.88 cfs/vault
Bypass Flow Rate =0 cfs/vault
Checks:VWQ < 0.5 PASS
Bypass Required FALSE
El. Out El. In
2,505.02 2,505.37
Inlet Baffel Wall El.Outlet Baffel Wall El.
2,504.772,505.27
𝑄𝑄𝑊𝑊𝑊𝑊=𝐶𝐶 ∗ 𝑖𝑖𝑊𝑊𝑊𝑊∗ 𝐴𝐴
V. 2018-10-15 30 Sep 2024
Catchment C WinCo Foods Rexburg
Project No. W2024005
Sand and Grease Trap
Peak Flow Design Storm 100 -year
Water Quality Design Storm 100
Peak Flow Rate (QPeak)7.44 cfs
Water Quality Flow Rate (QWQ)7.44 cfs
Design Calculations
Vault Size =1500 gallon Peak Throat Velocity (vPeak) =0.45
No. of S&G Traps =2 WQ Throat Velocity (vWQ) =0.45 fps
Baffle Spacing =20 inch
Throat Width =60 inch Allowed Max Flow rate (QMax,A) =4.15 cfs/vault
Total Throat Area =16.67 ft2 Max Flow rate (QMax) =3.72 cfs/vault
Bypass Flow Rate =0 cfs/vault
Checks:VWQ < 0.5 PASS
Bypass Required FALSE
El. Out El. In
2,505.02 2,505.37
Inlet Baffel Wall El.Outlet Baffel Wall El.
2,504.772,505.27
𝑄𝑄𝑊𝑊𝑊𝑊=𝐶𝐶 ∗ 𝑖𝑖𝑊𝑊𝑊𝑊∗ 𝐴𝐴
V. 2018-10-15 30 Sep 2024
Catchment D WinCo Foods Rexburg
Project No. W2024005
Sand and Grease Trap
Peak Flow Design Storm 100 -year
Water Quality Design Storm 100
Peak Flow Rate (QPeak)7.28 cfs
Water Quality Flow Rate (QWQ)7.28 cfs
Design Calculations
Vault Size =1500 gallon Peak Throat Velocity (vPeak) =0.44
No. of S&G Traps =2 WQ Throat Velocity (vWQ) =0.44 fps
Baffle Spacing =20 inch
Throat Width =60 inch Allowed Max Flow rate (QMax,A) =4.15 cfs/vault
Total Throat Area =16.67 ft2 Max Flow rate (QMax) =3.64 cfs/vault
Bypass Flow Rate =0 cfs/vault
Checks:VWQ < 0.5 PASS
Bypass Required FALSE
El. Out El. In
2,505.02 2,505.37
Inlet Baffel Wall El.Outlet Baffel Wall El.
2,504.772,505.27
𝑄𝑄𝑊𝑊𝑊𝑊=𝐶𝐶 ∗ 𝑖𝑖𝑊𝑊𝑊𝑊∗ 𝐴𝐴
V. 2018-10-15 30 Sep 2024
Catchment E WinCo Foods Rexburg
Project No. W2024005
Sand and Grease Trap
Peak Flow Design Storm 100 -year
Water Quality Design Storm 100
Peak Flow Rate (QPeak)3.08 cfs
Water Quality Flow Rate (QWQ)3.08 cfs
Design Calculations
Vault Size =1000 gallon Peak Throat Velocity (vPeak) =0.46
No. of S&G Traps =1 WQ Throat Velocity (vWQ) =0.46 fps
Baffle Spacing =20 inch
Throat Width =48 inch Allowed Max Flow rate (QMax,A) =3.33 cfs
Total Throat Area =6.67 ft2 Max Flow rate (QMax) =3.08 cfs
Bypass Flow Rate =0 cfs
Checks:VWQ < 0.5 PASS
Bypass Required FALSE
El. Out El. In
2,505.02 2,505.37
Inlet Baffel Wall El.Outlet Baffel Wall El.
2,504.772,505.27
𝑄𝑄𝑊𝑊𝑊𝑊=𝐶𝐶 ∗𝐶𝐶𝑊𝑊𝑊𝑊∗𝐶𝐶
V. 2018-10-15 30 Sep 2024
Catchment F WinCo Foods Rexburg
Project No. W2024005
Sand and Grease Trap
Peak Flow Design Storm 100 -year
Water Quality Design Storm 100
Peak Flow Rate (QPeak)4.87 cfs
Water Quality Flow Rate (QWQ)4.87 cfs
Design Calculations
Vault Size =1000 gallon Peak Throat Velocity (vPeak) =0.37
No. of S&G Traps =2 WQ Throat Velocity (vWQ) =0.37 fps
Baffle Spacing =20 inch
Throat Width =48 inch Allowed Max Flow rate (QMax,A) =3.33 cfs/vault
Total Throat Area =13.33 ft2 Max Flow rate (QMax) =2.44 cfs/vault
Bypass Flow Rate =0 cfs/vault
Checks:VWQ < 0.5 PASS
Bypass Required FALSE
El. Out El. In
2,505.02 2,505.37
Inlet Baffel Wall El.Outlet Baffel Wall El.
2,504.772,505.27
𝑄𝑄𝑊𝑊𝑊𝑊=𝐶𝐶 ∗𝐶𝐶𝑊𝑊𝑊𝑊∗𝐶𝐶
V. 2018-10-15 30 Sep 2024
Catchment G WinCo Foods Rexburg
Project No. W2024005
Sand and Grease Trap
Peak Flow Design Storm 100 -year
Water Quality Design Storm 100
Peak Flow Rate (QPeak)4.83 cfs
Water Quality Flow Rate (QWQ)4.83 cfs
Design Calculations
Vault Size =1000 gallon Peak Throat Velocity (vPeak) =0.36
No. of S&G Traps =2 WQ Throat Velocity (vWQ) =0.36 fps
Baffle Spacing =20 inch
Throat Width =48 inch Allowed Max Flow rate (QMax,A) =3.33 cfs/vault
Total Throat Area =13.33 ft2 Max Flow rate (QMax) =2.42 cfs/vault
Bypass Flow Rate =0 cfs/vault
Checks:VWQ < 0.5 PASS
Bypass Required FALSE
El. Out El. In
2,505.02 2,505.37
Inlet Baffel Wall El.Outlet Baffel Wall El.
2,504.772,505.27
𝑄𝑄𝑊𝑊𝑊𝑊=𝐶𝐶 ∗ 𝑖𝑖𝑊𝑊𝑊𝑊∗ 𝐴𝐴
V. 2018-10-15 30 Sep 2024
Catchment H WinCo Foods Rexburg
Project No. W2024005
Sand and Grease Trap
Peak Flow Design Storm 100 -year
Water Quality Design Storm 100
Peak Flow Rate (QPeak)1.29 cfs
Water Quality Flow Rate (QWQ)1.29 cfs
Design Calculations
Vault Size =1000 gallon Peak Throat Velocity (vPeak) =0.19
No. of S&G Traps =1 WQ Throat Velocity (vWQ) =0.19 fps
Baffle Spacing =20 inch
Throat Width =48 inch Allowed Max Flow rate (QMax,A) =3.33 cfs
Total Throat Area =6.67 ft2 Max Flow rate (QMax) =1.29 cfs
Bypass Flow Rate =0 cfs
Checks:VWQ < 0.5 PASS
Bypass Required FALSE
El. Out El. In
2,505.02 2,505.37
Inlet Baffel Wall El.Outlet Baffel Wall El.
2,504.772,505.27
𝑄𝑄𝑊𝑊𝑊𝑊=𝐶𝐶 ∗ 𝑖𝑖𝑊𝑊𝑊𝑊∗ 𝐴𝐴
V. 2018-10-15 30 Sep 2024
INLET, GUTTER AND PIPE CALCULATIONS
APPENDIX C - GEOTECHNICAL ENGINEERING
AND ADDITIONAL INFORMATION
Report Cover Page
Rexburg Retail
Development
Geotechnical Engineering Report
May 15, 2024 | Terracon Project No. 62245017
Prepared for:
WinCo Foods
650 N Armstrong Place
Boise, Idaho 83704
Geotechnical Engineering Report
Rexburg Retail Development | Rexburg, Idaho
May 15, 2024 | Terracon Project No. 62245017
Facilities | Environmental | Geotechnical | Materials i
Table of Contents
Report Summary .............................................................................................. i
Introduction .................................................................................................... 1
Project Description .......................................................................................... 1
Site Conditions ................................................................................................ 3
Geotechnical Characterization ......................................................................... 4
Seismic Site Class ............................................................................................ 5
Infiltration ...................................................................................................... 5
Corrosivity ...................................................................................................... 6
Geotechnical Overview .................................................................................... 7
Earthwork ....................................................................................................... 7
Site and Subgrade Preparation .................................................................... 8
Fill Material Types ..................................................................................... 8
Fill Placement and Compaction Requirements ................................................ 9
Grading and Drainage ................................................................................ 9
Earthwork Construction Considerations ....................................................... 10
Construction Observation and Testing ......................................................... 11
Shallow Foundations ..................................................................................... 11
Design Parameters – Compressive Loads ..................................................... 11
Foundation Construction Considerations ...................................................... 12
Floor Slabs .................................................................................................... 13
Floor Slab Design Parameters .................................................................... 13
Floor Slab Construction Considerations ........................................................ 14
Lateral Earth Pressures ................................................................................. 14
Design Parameters ................................................................................... 14
Subsurface Drainage for Below-Grade Walls ................................................. 16
Pavements .................................................................................................... 16
General Pavement Comments .................................................................... 16
Pavement Design Parameters .................................................................... 17
Pavement Section Thicknesses ................................................................... 17
Pavement Design Considerations ................................................................ 19
Pavement Construction Considerations ........................................................ 20
Pavement Maintenance ............................................................................. 20
General Comments ........................................................................................ 20
Figures
GeoModel
Attachments
Exploration and Testing Procedures
Geotechnical Engineering Report
Rexburg Retail Development | Rexburg, Idaho
May 15, 2024 | Terracon Project No. 62245017
Facilities | Environmental | Geotechnical | Materials ii
Site Location and Exploration Plans
Exploration and Laboratory Results
Supporting Information
Note: This report was originally delivered in a web-based format. Blue Bold text in the
report indicates a referenced section heading. The PDF version also includes hyperlinks
which direct the reader to that section and clicking on the logo will bring you
back to this page. For more interactive features, please view your project online at
client.terracon.com.
Refer to each individual Attachment for a listing of contents.
Geotechnical Engineering Report
Rexburg Retail Development | Rexburg, Idaho
May 15, 2024 | Terracon Project No. 62245017
Facilities | Environmental | Geotechnical | Materials i
Report Summary
Topic 1 Overview Statement 2
Project
Description
The project is located at the southeast corner of North 2nd East
and East Moody Road in Rexburg, Idaho.
The proposed approximately 84,000 square-foot WinCo Foods
Store and approximately 5,500 square-foot cross-dock building
will be part of about 17-acres of retail development and will be
constructed on the eastern portion of the development.
Geotechnical
Characterization
The near surface soils consisted of very soft to very stiff clays with
varying amounts of sand, gravel, and varying degrees of
cementation. Underlying gravels and sands were generally
medium dense to dense but ranged from loose to very dense in
locations.
Groundwater was encountered in four of the borings drilled for the
building at depths ranging from 28½ to 29 feet below the existing
surface.
Earthwork
Due to the site’s previous use as an agricultural field, the stripping
depth is anticipated to be about 12 inches.
Existing site soils can be reused as Site Grading Materials.
Fine grained soils are sensitive to moisture variation.
Shallow
Foundations
This section presents options for an allowable bearing pressure of
1 ,500 psf or 3,000 psf, depending on if WinCo elects to construct
foundations on native clay soils or to over-excavate and remove
the native clay.
Anticipated settlements: Approximately 1 inch total, ½ to ¾ inch
differential
Floor Slabs
Floor slabs should be supported on minimum 6 inches of
Aggregate Base over a minimum of 8 inches of Structural Fill or
Aggregate Base.
Pavements Recommendations for asphaltic concrete or Portland cement
concrete paving have been provided.
General
Comments
This section contains important information about the limitations
of this geotechnical engineering report.
1. If the reader is reviewing this report as a pdf, the topics above can be used to
access the appropriate section of the report by simply clicking on the topic itself.
2. This summary is for convenience only. It should be used in conjunction with the
entire report for design purposes.
Geotechnical Engineering Report
Rexburg Retail Development | Rexburg, Idaho
May 15, 2024 | Terracon Project No. 62245017
Facilities | Environmental | Geotechnical | Materials 1
Introduction
This report presents the results of our subsurface exploration and Geotechnical
Engineering services performed for the proposed WinCo Food Store development to be
located at the southeast corner of North 2nd East and East Moody Road in Rexburg,
Idaho. The purpose of these services was to provide information and geotechnical
engineering recommendations relative to:
■ Subsurface soil conditions
■ Groundwater conditions
■ Seismic site classification per IBC
■ Site preparation and earthwork
■ Foundation design and construction
■ Floor slab design and construction
■ Lateral earth pressure
■ Pavement design and construction
■ Stormwater management considerations
The geotechnical engineering Scope of Services for this project included the
advancement of borings, an infiltration rate test via test pit, laboratory testing,
engineering analysis, and preparation of this report.
Drawings showing the site and boring locations are on the Site Location and
Exploration Plan, respectively. The results of the laboratory testing performed on soil
samples obtained from the site during our field exploration are included on the boring
logs and/or as separate graphs in the Exploration Results section.
Project Description
Our initial understanding of the project was provided in our proposal and was discussed
during project planning. A period of collaboration has transpired since the project was
initiated, and our final understanding of the project conditions is as follows:
Item Description
Information
Provided
Project information is based on the details provided via email
from WinCo on February 23, 2024, a site plan was provided.
Geotechnical Engineering Report
Rexburg Retail Development | Rexburg, Idaho
May 15, 2024 | Terracon Project No. 62245017
Facilities | Environmental | Geotechnical | Materials 2
Item Description
Project
Description
The proposed WinCo Foods Store will be part of a proposed
retail development located on the southeast corner of North 2nd
East and East Moody Road in Rexburg, Idaho. The total
development will be approximately 17 acres, the proposed
WinCo Foods Store and cross-dock building will be constructed
in the eastern portion of the development.
Terracon’s geotechnical services were limited to the proposed
WinCo Foods Store and cross-dock building, and the associated
parking and drive areas.
Limited exploration of a single bore hole was performed on lots
2, 3, and 4, boring logs for these have been included in the
appendix for informational purposes. Further exploration and
recommendations for these lots was excluded from our services
for this project and site-specific geotechnical studies will need to
be performed for those lots.
Proposed
Structure
The provided site plan indicates the proposed single-story
WinCo store will measure approximately 84,000-square-feet in
plan area and cross-dock building approximately 5,500-square-
feet in plan area.
Building
Construction
We have assumed the proposed WinCo store will be typical of
other WinCo structures recently constructed. Loads and
construction have been assumed consistent with WinCo Foods
Site Design Criteria Manual, dated January 1, 2011, which
includes masonry-block load-bearing and non-load-bearing
walls, steel columns, girders, and joists for support of the roof
structure. The floors will be slab-on-grade.
Maximum Loads
Anticipated structural loads are:
■ Columns: 130 kips
■ Walls: 4 kips per linear foot (klf)
■ Slabs: 300 pounds per square foot (psf), 5 kip point load
Grading/Slopes Grading plans are not available at this time. Permanent cuts
and/or fills are anticipated to be about 3 feet or less.
Below-Grade
Structures
The proposed truck loading ramp is anticipated to be
approximately 4 feet below the finished floor elevation.
Geotechnical Engineering Report
Rexburg Retail Development | Rexburg, Idaho
May 15, 2024 | Terracon Project No. 62245017
Facilities | Environmental | Geotechnical | Materials 3
Item Description
Pavements
A parking area will be constructed west of the proposed
structure and a truck access drive will be constructed south of
the store, which will lead to a proposed cross-dock. Pavements
are anticipated to consist of asphaltic concrete and/or Portland
cement concrete. WinCo has requested pavement section
thickness recommendations for the store and parking based on
equivalent single axle loads (ESALs) that approximately
represent 10-year and 20-year design lives. Based on past
WinCo projects, traffic volumes for these two periods are
assumed to consist of the following:
Standard-Duty:
■ 90,000 flexible ESALs (approximately 20-year design life)
■ 50,000 flexible ESALs (approximately 10-year design life)
Heavy-Duty:
■ 180,000 flexible ESALs (approximately 20-year design life)
■ 90,000 flexible ESALs (approximately 10-year design life)
Additional Truck Traffic due to Cross-Dock:
The following ESALs were calculated based on the truck load and
traffic data provided for the cross-dock during the proposal
phase:
■ 325,000 flexible ESALs (approximately 20-year design life)
■ 146,500 flexible ESALs (approximately 10-year design life)
Since the truck traffic accessing the cross-dock will be using the
same travel path and parking areas as the “normal” heavy duty
truck traffic, the ESALs have been added to the heavy-duty
pavement design calculations.
Building Code 2018 IBC
Stormwater
Management
Infiltration testing was performed within Test Pit No. TP-24,
excavated in the proposed parking area west of the store.
Results of the infiltration rate testing are discussed in
Infiltration.
Terracon should be notified if any of the above information is inconsistent with the
planned construction, as modifications to our recommendations may be necessary.
Site Conditions
The following description of site conditions is derived from our site visit in association
with the field exploration and our review of publicly available maps.
Geotechnical Engineering Report
Rexburg Retail Development | Rexburg, Idaho
May 15, 2024 | Terracon Project No. 62245017
Facilities | Environmental | Geotechnical | Materials 4
Item Description
Parcel
Information
The project is located at the southeast corner of North 2nd East
and East Moody Road in Rexburg, Idaho.
Latitude/Longitude (approximate): 43.8540°N, 111.7756°W
(See Exhibit D)
Existing
Improvements
The site is in an agricultural field. The site is bordered by a
Wendy’s Restaurant to the northwest of the proposed
development. A paved access road boarders the Wendy’s lot and
ditches for flood irrigation are located around the perimeter of
the existing field. There is also a retail development north of the
site and a business development south of the site.
Current Ground
Cover
At the time of exploration, the agricultural field was dormant for
winter. It is unknown to Terracon if the field will continue to be
cultivated and the current ground cover of the site is unknown.
Existing
Topography
Based on Google Earth Pro, the site is relatively level with about
4 feet elevation difference across the site.
Geotechnical Characterization
We have developed a general characterization of the subsurface conditions based upon
our review of the subsurface exploration, laboratory data, geologic setting and our
understanding of the project. This characterization, termed GeoModel, forms the basis of
our geotechnical calculations and evaluation of the site. Conditions observed at each
exploration point are indicated on the individual logs. The individual logs can be found in
the Exploration Results and the GeoModel can be found in the Figures attachment of
this report.
As part of our analyses, we identified the following model layers within the subsurface
profile. For a more detailed view of the model layer depths at each boring location, refer
to the GeoModel.
Model
Layer Layer Name General Description
1 Clay Lean clay and fat clay with varying amounts of sand and
gravel, and varying degrees of cementation.
2 Sand Sand with varying amounts of clay, silt, and gravel.
3 Gravel Gravel with varying amounts of clay, silt, sand, and
cobbles, and varying degrees of cementation.
Geotechnical Engineering Report
Rexburg Retail Development | Rexburg, Idaho
May 15, 2024 | Terracon Project No. 62245017
Facilities | Environmental | Geotechnical | Materials 5
The borings and test pit were monitored during exploration for the presence and depth
to groundwater. At the time exploration, groundwater was encountered in borings B-3,
B-5, B-7, and B-11 at depths between 28½ and 29 feet below existing ground surface.
Groundwater conditions may be different at the time of construction. Groundwater
conditions may change because of land use changes at the site and the surrounding
area, seasonal variations in irrigation, rainfall, runoff, and other conditions not apparent
at the time of drilling. Long-term groundwater monitoring was outside the scope of
services for this project.
Seismic Site Class
The seismic design requirements for buildings and other structures are based on Seismic
Design Category. Site Classification is required to determine the Seismic Design
Category for a structure. The Site Classification is based on the upper 100 feet of the
site profile defined by a weighted average value of either shear wave velocity, standard
penetration resistance, or undrained shear strength in accordance with Section 20.4 of
ASCE 7 and the International Building Code (IBC). Based on the soil properties observed
at the site and as described on the exploration logs and results, our professional opinion
is for that a Seismic Site Classification of D be considered for the project. Subsurface
explorations at this site were extended to a maximum depth of 31½ feet. The site
properties below the boring depth to 100 feet were estimated based on our experience
and knowledge of geologic conditions of the general area. Additional deeper borings or
geophysical testing may be performed to confirm the conditions below the current
exploration depth.
Infiltration
Terracon performed a field infiltration rate test in Test Pit TP-24. The test was performed
in general accordance with in-situ small scale pilot infiltration test methods. This test
includes both constant and falling head infiltration rate testing performed within the test
pit. Testing was conducted using about a foot of water at the bottom of the test pit. The
result of the test is summarized in the following table.
Location
Approximate
Depth
(feet)1
Soil Type at Depth of Test Field Infiltration
Rate
TP-24 4 Poorly Graded Gravel with Clay and Sand 5 inches/hour
1. Approximate depth below the existing ground surface.
Geotechnical Engineering Report
Rexburg Retail Development | Rexburg, Idaho
May 15, 2024 | Terracon Project No. 62245017
Facilities | Environmental | Geotechnical | Materials 6
The field test result is not intended to be a design rate; it represents the test results at
the depth and location indicated. The rate used for design should be determined by the
designer by applying an appropriate factor of safety. A minimum factor of safety of two
should be used. A greater factor of safety may be warranted. The designer should select
the design factor of safety that considers the severity of the impacts to the public if the
system were to fail, the facility geometry, if the facility includes outlet structures, the
degree of influent control to reduce siltation and bio-buildup, the quality and frequency
of long-term maintenance, etc. In addition, the following factors should be considered
when selecting the factor of safety for design:
Test Procedures: The infiltration test likely included both vertical and lateral
seepage, whereas seepage from storm water infiltration systems may primarily
flow downward, depending on the geometry and details of the system.
Water Quality: Infiltration tests are typically performed using clear water,
whereas the storm water will likely not be clear, but may contain organics, fines,
and grease/oil. The presence of these deleterious materials will tend to decrease
the rate that water percolates from the infiltration systems. Design of the
stormwater infiltration system should account for the presence of these materials
and should incorporate structures/devices to remove these deleterious materials.
Long-Term Performance/Maintenance: With time, the bottoms of infiltration
systems tend to plug with organics, sediments, and other debris. Long-term
maintenance will likely be required to remove these deleterious materials to
improve the actual infiltration rate. The designer should base the project design
and selection of the infiltration rate on the assumption that little to no
maintenance will be performed.
Soil Variability: Based on the soils encountered during our exploration, we
expect the infiltration rates of the soils could vary over short distances due to
variations in fines content, cementation, and soil type. Infiltrating into soils with a
higher percentage of silt or clay would be expected to have lower infiltration rates
and cemented soils can have no infiltration. The design elevations and sizes of
the proposed infiltration systems should account for this expected variability in
the percolation rate. Excavation for stormwater management facilities should
extend below any cemented soils and be replaced with appropriate filtering
sediments, as appropriate.
Corrosivity
C orrosivity testing is currently be conducted at the issuance of this report. Terracon will
provide the corrosivity testing results via an addendum letter once completed.
Geotechnical Engineering Report
Rexburg Retail Development | Rexburg, Idaho
May 15, 2024 | Terracon Project No. 62245017
Facilities | Environmental | Geotechnical | Materials 7
Geotechnical Overview
The site appears suitable for the proposed construction based upon geotechnical
conditions encountered in the test pit and borings, provided that the recommendations
provided in this report are implemented in the design and construction phases of this
project.
■ The subsurface materials generally consisted of clay soils with varying amounts of
sand overlying sand and gravel deposits. Groundwater was encountered at depths
between 28½ to 29 feet below the existing ground surface.
■ Sandy fat clay was encountered in boring no. B-20, fat clay soils should be
removed from structures areas.
■ Based on the conditions encountered and estimated load-settlement relationships,
the proposed structures can be supported on conventional continuous or spread
footings. The Shallow Foundations section presents options for constructing
footings on native clay soils or removing the clay to support foundations on native
coarse grained soils, Structural Fill, or Aggregate Base.
■ The near surface fine-grained soils could become unstable with typical earthwork
and construction traffic, especially after precipitation events. The effective
drainage should be completed early in the construction sequence and maintained
after construction to avoid potential issues.
■ If possible, the grading should be performed during the warmer and drier times of
the year. If grading is performed during the winter months or wet periods of time,
an increased risk for possible undercutting and replacement of unstable subgrade
will persist. Additional site preparation recommendations, including subgrade
improvement and fill placement, are provided in the Earthwork section.
The recommendations contained in this report are based upon the results of field and
laboratory testing (presented in the Exploration Results), engineering analyses, and
our current understanding of the proposed project. The General Comments section
provides an understanding of the report limitations.
Earthwork
Earthwork is anticipated to include clearing and grubbing, excavations, and engineered
fill placement. The following sections provide recommendations for use in the
preparation of specifications for the work. Recommendations include critical quality
criteria, as necessary, to render the site in the state considered in our geotechnical
engineering evaluation for foundations, floor slabs, and pavements.
Geotechnical Engineering Report
Rexburg Retail Development | Rexburg, Idaho
May 15, 2024 | Terracon Project No. 62245017
Facilities | Environmental | Geotechnical | Materials 8
Site and Subgrade Preparation
Prior to construction, undocumented fills, deleterious materials such as vegetation, root
systems, topsoil, and soft, frozen, disturbed, or otherwise unsuitable materials should be
completely removed from the proposed building and pavement areas. For estimating
purposes, the minimum stripping depth will be approximately 12 inches within the
agricultural field. Surfaces exposed after excavation should be free of mounds and
depressions that could prevent uniform compaction. Subgrade soils exposed during
construction will be susceptible to rutting or pumping under construction traffic when
wet. See Earthwork Construction Considerations.
As part of our exploration, Test Pit No. TP-24 was excavated for infiltration rate testing.
Since the test pit was tamped (not compacted) when replacing the soils, re-excavation
and compaction of the test pit area is required prior to construction. Care should be
taken during construction to identify the previous test pit location in the proposed
improvement areas and to completely remove the loose backfill and backfill with
compacted material under the observation of the Geotechnical Engineer or
representative. Backfill material may be existing native soils or Structural Fill depending
on the final site grading.
All exposed areas which will receive fill or will support foundations, once properly cleared
and benched where necessary, should be scarified to a minimum depth of 10 inches,
moisture conditioned as necessary, and compacted to the requirements outlined in Fill
Placement and Compaction Requirements.
The subgrade should be proofrolled with an adequately loaded vehicle such as a fully-
loaded tandem-axle dump truck. The proofrolling should be performed under the
observation of the Geotechnical Engineer or representative. Areas excessively deflecting
under the proofroll should be delineated and subsequently addressed by the
Geotechnical Engineer. Such areas should be removed and replaced with compacted
Structural Fill or Aggregate Base. Excessively wet or dry material should be either
removed or moisture conditioned and recompacted.
Structural Fill (or Aggregate Base) soils should then be placed and compacted to the
proposed design grade and the moisture content and compaction of subgrade soils
should be maintained until foundation or pavement construction.
Fill Material Types
Fill material requirements vary depending on the intended use of the material. The
following table summarizes the fill material designations and the zones where they may
be placed. Regardless of its source, compacted fill should consist of approved materials
that are free of organic matter and debris. Frozen material should not be used, and fill
should not be placed on a frozen subgrade.
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Soil Type 1 Materials Acceptable Location
for Placement
Site Grading
Materials
On-site soils may be used as Site
Grading Materials, provided they are
free of topsoil, vegetation, construction
debris, and other deleterious materials.
Pavement and non-
building areas.
Structural Fill
and Subbase
Structural Fill and Subbase should
consist of 3-inch or 6-inch minus
uncrushed aggregates meeting the
requirements of Idaho Standards for
Public Works Construction (ISPWC)
Section 801.
Building and pavement
areas with the exception
of those areas where
Aggregate Base is
specified.
Aggregate Base
Aggregate Base should meet the
requirements for ¾-inch (Type I)
crushed aggregate in accordance with
ISPWC Section 802.
Base course material for
pavements and floor
slabs and all other
locations within building
and pavement areas.
1. A sample of each material type should be submitted to the Geotechnical Engineer
for evaluation prior to use on this site.
Fill Placement and Compaction Requirements
Fill materials should be placed in horizontal, loose lifts not exceeding 8 inches in
thickness when heavy, self-propelled compaction equipment is used and 4 to 6 inches in
thickness when hand-guided equipment (i.e. jumping jack or plate compactor) is used.
Fill should be adjusted to within 0 to +3 percent of the optimum moisture content and
compacted to the minimum percentages of either maximum dry density or relative
density shown in the following table, whichever is appropriate for the material being
used. Fill should meet the density requirements presented in the following table.
Location
Percent of Maximum
Dry Density, ASTM
D698
Percent Relative
Density, ASTM
D4253/D4254
Beneath buildings, slabs, walkways,
and paved areas 98 80
Other areas of fill and backfill 95 75
Grading and Drainage
All grades must provide effective drainage away from the building during and after
construction and should be maintained throughout the life of the structure. Water
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retained next to the building can result in soil movements greater than those discussed
in this report. Greater movements can result in unacceptable differential floor slab
and/or foundation movements, cracked slabs and walls, and roof leaks. The roof should
have gutters/drains with downspouts that discharge onto splash blocks at a distance of
at least 10 feet from the building.
Exposed ground should be sloped and maintained at a minimum 5% away from the
building for at least 10 feet beyond the perimeter of the building. Locally, flatter grades
may be necessary to transition ADA access requirements for flatwork. After building
construction and landscaping have been completed, final grades should be verified to
document effective drainage has been achieved. Grades around the structure should also
be periodically inspected and adjusted, as necessary, as part of the structure’s
maintenance program. Where paving or flatwork abuts the structure, a maintenance
program should be established to effectively seal and maintain joints and prevent
surface water infiltration.
Earthwork Construction Considerations
Shallow excavations for the proposed structure are anticipated to be accomplished with
conventional construction equipment. Upon completion of filling and grading, care should
be taken to maintain the subgrade water content prior to construction of grade-
supported improvements such as floor slabs and pavements. Construction traffic over
the completed subgrades should be avoided. The site should also be graded to prevent
ponding of surface water on the prepared subgrades or in excavations. Water collecting
over or adjacent to construction areas should be removed. If the subgrade freezes,
desiccates, saturates, or is disturbed, the affected material should be removed, or the
materials should be scarified, moisture conditioned, and recompacted prior to floor slab
construction.
Exposed soils will likely be susceptible to rutting or pumping under construction traffic
when wet. Soils that rut, pump, desiccate, or are otherwise disturbed are not suitable for
building pad and pavement areas, and should be removed and replaced with Structural
Fill. Measures that may help reduce disturbance of exposed soils include performing
earthwork during warm, dry weather, the use of light track-mounted equipment, and
avoidance of heavy repeated traffic over a given area.
As a minimum, excavations should be performed in accordance with OSHA 29 CFR, Part
1926, Subpart P, “Excavations” and its appendices, and in accordance with any
applicable local and/or state regulations. Construction site safety is the sole
responsibility of the contractor who controls the means, methods, and sequencing of
construction operations. Under no circumstances shall the information provided herein
be interpreted to mean Terracon is assuming responsibility for construction site safety or
the contractor's activities; such responsibility shall neither be implied nor inferred.
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Construction Observation and Testing
The earthwork efforts should be observed by the Geotechnical Engineer (or others under
their direction). Observation should include documentation of adequate removal of
surficial materials (vegetation, topsoil, and pavements), evaluation and remediation of
existing fill materials, as well as proofrolling and mitigation of unsuitable areas
delineated by the proofroll.
Each lift of compacted fill should be tested, evaluated, and reworked, as necessary, as
recommended by the Geotechnical Engineer prior to placement of additional lifts.
In areas of foundation excavations, the bearing subgrade should be evaluated by the
Geotechnical Engineer. If unanticipated conditions are observed, the Geotechnical
Engineer should prescribe mitigation options.
In addition to the documentation of the essential parameters necessary for construction,
the continuation of the Geotechnical Engineer into the construction phase of the project
provides the continuity to maintain the Geotechnical Engineer’s evaluation of subsurface
conditions, including assessing variations and associated design changes.
Shallow Foundations
If the site has been prepared in accordance with the requirements noted in Earthwork,
the following design parameters are applicable for shallow foundations.
Design Parameters – Compressive Loads
Item Description
Maximum Net
Allowable Bearing
Pressure 1, 2
1,500 psf 3,000 psf
Required Bearing
Stratum 3
Native clay soils, Structural
Fill, or Aggregate Base.
Native granular soils,
Structural Fill, or Aggregate
Base.
If selected, Structural Fill or Aggregate Base should extend
to native soils prepared meeting the requirements of
Earthwork.
Native clay or granular soils, Structural Fill, or Aggregate
Base should be prepared and compacted to meet the
requirements of Earthwork.
Geotechnical Engineering Report
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May 15, 2024 | Terracon Project No. 62245017
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Item Description
Minimum Foundation
Dimensions
Columns: 30 inches
Continuous: 18 inches
Ultimate Coefficient of
Sliding Resistance 5
0.40 0.45
(An appropriate factor of safety should be applied to this
value for use in design.)
Minimum Embedment
below
Finished Grade 6
Exterior footings: 36 inches (for frost protection)
Interior footings not subject to frost: 18 inches
Estimated Total
Settlement from
Structural Loads 2
Approximately 1 inch or less
Estimated Differential
Settlement 2, 6 Typically ½ to ¾ of the total settlement
1. The maximum net allowable bearing pressure is the pressure in excess of the minimum
surrounding overburden pressure at the footing base elevation. Values assume that
exterior grades are no steeper than 20% within 10 feet of structure.
2. Values provided are for maximum loads noted in Project Description. Additional
geotechnical consultation will be necessary if higher loads are anticipated.
3. Unsuitable or soft soils should be overexcavated and replaced per the recommendations
presented in Earthwork.
4. Can be used to compute sliding resistance where foundations are placed on suitable
soil/materials. Frictional resistance for granular materials is dependent on the bearing
pressure which may vary due to load combinations. For fine-grained materials, lateral
resistance using cohesion should not exceed ½ the dead load.
5. Embedment necessary to reduce the effects of frost and/or seasonal water content
variations. For sloping ground, maintain depth below the lowest adjacent exterior grade
within 5 horizontal feet of the structure.
6. Differential settlements are noted for equivalent-loaded foundations and bearing
elevation as measured over a span of 50 feet.
Foundation Construction Considerations
As noted in Earthwork, the footing excavations should be evaluated under the
observation of the Geotechnical Engineer. The base of all foundation excavations should
be free of water and loose soil, prior to placing concrete. Concrete should be placed soon
after excavating to reduce bearing soil disturbance. Care should be taken to prevent
wetting or drying of the bearing materials during construction. Excessively wet or dry
material or any loose/disturbed material in the bottom of the footing excavations should
be removed/reconditioned before foundation concrete is placed.
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Over-excavation for the Structural Fill or Aggregate Base placement below footings
should be conducted as shown below. The zone of Structural Fill or Aggregate Base
should, as a minimum, extend a horizontal distance beyond the perimeter of the
foundations equal to 2/3 the depth of the Structural Fill or Aggregate Base (e.g., 16
inches horizontally for 24 inches of depth). The over-excavation should be backfilled up
to the footing base elevation with Structural Fill or Aggregate Base placed as
recommended in the Earthwork section.
Floor Slabs
Design parameters for floor slabs assume the requirements for Earthwork have been
followed. Specific attention should be given to positive drainage away from the structure
and positive drainage of the aggregate base beneath the floor slab.
Floor Slab Design Parameters
Item Description
Floor Slab Support 1 . 2
Minimum 6 inches of ¾-inch-minus crushed Aggregate Base
compacted in accordance with Earthwork.
Subgrade compacted to recommendations in Earthwork.
Modulus of Subgrade
Reaction 1 50 pounds per square inch per inch (psi/in) for point loads
1. Floor slabs should be structurally independent of building footings or walls to reduce
the possibility of floor slab cracking caused by differential movements between the
slab and foundation.
2. Aggregate Base and Structural Fill should meet the materials and compaction
requirements as outlined in Earthwork.
Structural
Fill or
Aggregate
Base
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May 15, 2024 | Terracon Project No. 62245017
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The use of a vapor retarder should be considered beneath concrete slabs on grade
covered with wood, tile, carpet, or other moisture sensitive or impervious coverings,
when the project includes humidity-controlled areas, or when the slab will support
equipment sensitive to moisture. When conditions warrant the use of a vapor retarder,
the slab designer should refer to ACI 302 and/or ACI 360 for procedures and cautions
regarding the use and placement of a vapor retarder.
Saw-cut contraction joints should be placed in the slab to help control the location and
extent of cracking. For additional recommendations, refer to the ACI Design Manual.
Joints or cracks should be sealed with a waterproof, non-extruding compressible
compound specifically recommended for heavy duty concrete pavement and wet
environments.
Where floor slabs are tied to perimeter walls or turn-down slabs to meet structural or
other construction objectives, our experience indicates differential movement between
the walls and slabs will likely be observed in adjacent slab expansion joints or floor slab
cracks beyond the length of the structural dowels. The Structural Engineer should
account for potential differential settlement through use of sufficient control joints,
appropriate reinforcing or other means.
Floor Slab Construction Considerations
Finished subgrade, within and for at least 10 feet beyond the floor slab, should be
protected from traffic, rutting, or other disturbance and maintained in a relatively moist
condition until floor slabs are constructed. If the subgrade becomes damaged or
desiccated prior to construction of floor slabs, the affected material should be removed,
and structural fill should be added to replace the resulting excavation. Final conditioning
of the finished subgrade should be performed immediately prior to placement of the floor
slab support course.
The Geotechnical Engineer should observe the condition of the floor slab subgrades
immediately prior to placement of the floor slab support course, reinforcing steel, and
concrete. Attention should be paid to high traffic areas that were rutted and disturbed
earlier, and to areas where backfilled trenches are located.
Lateral Earth Pressures
Design Parameters
Structures with unbalanced backfill levels on opposite sides should be designed for earth
pressures at least equal to values indicated in the following table. Earth pressures will be
influenced by structural design of the walls, conditions of wall restraint, methods of
Geotechnical Engineering Report
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May 15, 2024 | Terracon Project No. 62245017
Facilities | Environmental | Geotechnical | Materials 15
construction, and/or compaction and the strength of the materials being restrained. Two
wall restraint conditions are shown in the diagram below. Active earth pressure is
commonly used for design of free-standing cantilever retaining walls and assumes wall
movement. The “at-rest” condition assumes no wall movement and is commonly used
for basement walls, loading dock walls, or other walls restrained at the top. The
recommended design lateral earth pressures do not include a factor of safety and do not
provide for possible hydrostatic pressure on the walls.
Lateral Earth Pressure Design Parameters
Earth
Pressure
Condition 1
Coefficient for
Backfill Type 2
Surcharge
Pressure p1 (psf) 3
Unsaturated
Equivalent Fluid
Pressures (psf) 2, 4, 5
Active (Ka) Structural Fill - 0.28
Fine Grained - 0.36
(0.28)S
(0.36)S
(35)H
(40)H
Active (Ka) Structural Fill - 0.44
Fine Grained - 0.53
(0.44)S
(0.53)S
(55)H
(58)H
At-Rest (Kp) Structural Fill - 3.54
Fine Grained - 2.77
--
--
(440)H
(305)H
1. For active earth pressure, wall must rotate about base, with top lateral movements
0.002 H to 0.004 H, where H is wall height. For passive earth pressure, wall must
move horizontally to mobilize resistance. Clay soils should not be used as backfill
behind the wall.
2. Uniform, horizontal backfill, with a maximum unit weight of 125 pcf and internal
friction angle of 34 degrees for Structural Fill and a maximum unit weight of 110 pcf
and internal friction angle of 28 degrees for native fine-grained soils.
3. Uniform surcharge, where S is surcharge pressure.
4. Loading from heavy compaction equipment is not included.
5. No safety factor is included in these values.
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Backfill placed against structures should consist of granular soils or low plasticity fine-
grained soils. For these values to be valid, the wall backfill should extend out and up
from the base of the wall at an angle of 30 degrees from horizontal, or flatter.
Footings, floor slabs or other loads bearing on backfill behind walls may have a
significant influence on the lateral earth pressure. Placing footings within wall backfill
and in the zone of active soil influence on the wall should be avoided unless structural
analyses indicate the wall can safely withstand the increased pressure.
The lateral earth pressure recommendations given in this section are applicable to the
design of rigid retaining walls subject to slight rotation, such as cantilever, or gravity
type concrete walls. These recommendations are not applicable to the design of modular
block - geogrid reinforced backfill walls (also termed MSE walls). Recommendations
covering these types of wall systems are beyond the scope of services for this
assignment. However, we would be pleased to develop a proposal for evaluation and
design of such wall systems upon request.
Subsurface Drainage for Below-Grade Walls
A perforated rigid plastic drain line installed behind the base of walls and extends below
adjacent grade is recommended to prevent hydrostatic loading on the walls. The invert
of a drain line around a below-grade building area or exterior retaining wall should be
placed near foundation bearing level. The drain line should be sloped to provide positive
gravity drainage to daylight or to a sump pit and pump. The drain line should be
surrounded by clean, free-draining granular material having less than 5% passing the
No. 200 sieve, such as ISPWC Section 703 Part 2E ¾ inch minus coarse aggregate for
concrete. The free-draining aggregate should be encapsulated in a filter fabric. The
granular fill should extend to within 2 feet of final grade.
As an alternative to free-draining granular fill, a prefabricated drainage structure may be
used. A prefabricated drainage structure is a plastic drainage core or mesh which is
covered with filter fabric to prevent soil intrusion and is fastened to the wall prior to
placing backfill.
Pavements
General Pavement Comments
Pavement designs are provided for the traffic conditions and pavement life conditions as
noted in Project Description and in the following sections of this report. A critical
aspect of pavement performance is site preparation. Pavement designs noted in this
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section must be applied to the site which has been prepared as recommended in the
Earthwork section.
Pavement Design Parameters
Designs for asphaltic concrete (AC) and Portland cement concrete (PCC) pavement
sections are in general accordance with the procedures outlined in the 1993 Guideline
for Design of Pavement Structures by the American Association of State Highway and
Transportation Officials (AASHTO).
An R-Value test was performed on a soil sample from boring No. B-20, based on this, an
R-Value of 5 was used for pavement section design. The pavement sections
recommended below assume the native clay for subgrade support. If the clay subgrade
will be removed during site grading, we should be notified as a reduction in pavement
section thickness may be possible.
Since the truck traffic accessing the cross-dock will be using the same travel path and
parking areas as the “normal” heavy duty truck traffic, the calculated ESALs have been
added to the heavy-duty pavement design calculations. Based on the provided traffic
information, the following ESALs were used in flexible pavement section design:
■ Standard Duty – 20-year design – 90,000 flexible ESALs
■ Standard Duty – 10-year design – 50,000 flexible ESALs
■ Heavy Duty (including cross-dock) – 20-year design – 505,000 flexible ESALs
■ Heavy Duty (including cross-dock) – 10-year design – 236,500 flexible ESALs
Pavement Section Thicknesses
Flexible pavement sections with options of using Aggregate Base and Subbase are
presented in the following table.
Asphaltic Concrete Design – Parking Lot and Drive Aisles 1
Material 2
Thickness (inches)
20-Year Design Life 10-Year Design Life
Standard
Duty
Heavy
Duty
Standard
Duty
Heavy
Duty
Asphaltic Concrete 3 3.5 4.0 3.0 4.0
Aggregate Base 7 .0 8 .0 6.0 8.0
Geotechnical Engineering Report
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May 15, 2024 | Terracon Project No. 62245017
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Asphaltic Concrete Design – Parking Lot and Drive Aisles 1
Material 2
Thickness (inches)
20-Year Design Life 10-Year Design Life
Standard
Duty
Heavy
Duty
Standard
Duty
Heavy
Duty
Subbase 8.0 14 .0 8.0 10.0
Total Pavement 18 .5 26 .0 17.0 22.0
1. See Project Description for more specifics regarding traffic.
2. All materials should meet the requirements of the current edition of the Idaho
Standards for Public Works Construction (ISPWC).
3. Asphaltic cement should be PG 64-28 Performance Graded Asphalt.
For areas subject to concentrated, repetitive loading conditions such as truck docks,
dumpster pads, and ingress/egress aprons we recommend using a PCC pavement. For
dumpster pads, the concrete pavement area should be large enough to support the
container and tipping axle of the refuse truck.
Portland Cement Concrete Design – Truck Docks, Dumpster Pad, and
Ingress/Egress Aprons
Material 1 Thickness (inches)
PCC 2 7.0
Aggregate Base 8.0
Total Pavement 15.0
1. All materials should meet requirements of the current edition of the Idaho
Standards for Public Works Construction (ISPWC).
2. Concrete Pavement – Air entrained and have a minimum compressive strength of
4,000 psi after 28 days of laboratory curing per ASTM C31
Pavement sections should be placed on subgrade prepared in accordance with
Earthwork. Edge restraints (i.e. concrete curbs or aggregate shoulders) should be
planned along curves and areas of maneuvering vehicles.
Where practical, we recommend early-entry cutting of crack-control joints in PCC
pavements. Cutting of the concrete in its “green” state typically reduces the potential for
micro-cracking of the pavements prior to the crack control joints being formed,
compared to cutting the joints after the concrete has fully set. Micro-cracking of
pavements may lead to crack formation in locations other than the sawed joints, and/or
reduction of fatigue life of the pavement.
Geotechnical Engineering Report
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Proper joint spacing will be required to prevent excessive slab curling and shrinkage
cracking. Joints should be sealed to prevent entry of foreign material and doweled where
necessary for load transfer. PCC pavement details for joint spacing, joint reinforcement,
and joint sealing should be prepared in accordance with ACI 330 and ACI 325.
Pavement Design Considerations
Long-term pavement performance will depend on several factors, including reducing or
preventing increases in subgrade moisture content and providing preventive
maintenance. In general, increases in the moisture content of subsurface soils can result
in adverse effects to the pavement section, including frost susceptibility or loss of
subgrade strength. Water allowed to pond on or adjacent to the pavements could
saturate the subgrade and contribute to premature pavement deterioration.
Openings in the pavement surface, such as a landscape island, are sources for water
infiltration into the surrounding pavement section and subgrade. Water can collect in an
island and migrate into the underlying subgrade soils, thereby degrading support of the
pavement. This is especially applicable for islands with raised concrete curbs, irrigated
vegetation, and near-surface soils with low permeability. The civil design for pavements
with these conditions should include features to restrict or collect and discharge excess
water from an island or other landscaped/irrigated areas. Examples of these features are
impermeable barriers that reduce lateral migration of water such as a cutoff barrier
installed to a depth below the pavement section and edge drains connected to the
storm-water collection system or other suitable outlet. The following should be
considered as minimum recommendations in the design and construction of pavements:
■ Provide a minimum 2% grade in the ground surface away from the edge of
pavements.
■ Provide a minimum 2% cross slope for the subgrade and pavement surface to
promote proper surface drainage.
■ Install pavement drainage at the perimeter of areas where frequent wetting, such
as from irrigation or other sources of water, is anticipated.
■ Install joint sealant and seal cracks promptly.
■ Seal all landscaped areas adjacent to pavements to reduce moisture migration to
subgrade soils.
■ Place compacted low permeability backfill against the exterior side of curb and
gutter.
■ Place curb, gutter and/or sidewalk directly on clay subgrade soils rather than on
unbound granular base course materials.
If, due to requirements to match adjacent grades and/or ADA requirements, a 2% slope
in the parking areas is not achievable in all areas, the grade should be designed using as
close to a 2% minimum slope as project constraints will allow, and the final slopes
Geotechnical Engineering Report
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should provide positive drainage from all paved surfaces. Care should be taken during
construction, so the constructed grades are not less than designed.
Pavement Construction Considerations
Pavement sections should be placed on properly prepared subgrade, as described in
Earthwork. As construction proceeds, the subgrade may be disturbed or altered due to
utility excavations, construction traffic, desiccation, or rainfall. As a result, the
pavement subgrade may become unsuitable for pavement support. The long-term
effects of localized areas of inadequately prepared subgrade may result in cracks or
potholes in the pavement. Therefore, the subgrade should be carefully evaluated at the
time of paving for signs of disturbance or rutting. If disturbance or rutting has occurred,
subgrade areas should be reworked, moisture conditioned, and properly compacted to
the recommendations in this report immediately prior to placing the pavement section
materials.
In areas of prepared subgrade or partial thickness pavement, the contractor should limit
traffic to equipment necessary to construct the pavement section. Heavily loaded
vehicles operating on these surfaces may cause significant damage, resulting in
deterioration and reduction in pavement life.
Pavement Maintenance
The pavement sections represent minimum recommended thicknesses and, as such,
periodic upkeep should be anticipated. Preventive maintenance should be planned and
provided for through an on-going pavement management program. Maintenance
activities are intended to slow the rate of pavement deterioration and to preserve the
pavement investment. Pavement care consists of both localized (e.g., crack and joint
sealing and patching) and global maintenance (e.g., surface sealing). Preventative
maintenance is usually the first priority when implementing a planned pavement maintenance
program and provides a relatively high return on investment for pavements. Even with
periodic maintenance, some movements and related cracking may still occur, and repairs
may be required.
General Comments
Our analysis and opinions are based upon our understanding of the project, the
geotechnical conditions in the area, and the data obtained from our site exploration.
Variations will occur between exploration point locations or due to the modifying effects
of construction or weather. The nature and extent of such variations may not become
evident until during or after construction. Terracon should be retained as the
Geotechnical Engineer, where noted in this report, to provide observation and testing
Geotechnical Engineering Report
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services during pertinent construction phases. If variations appear, we can provide
further evaluation and supplemental recommendations. If variations are noted in the
absence of our observation and testing services on-site, we should be immediately
notified so that we can provide evaluation and supplemental recommendations.
Our Scope of Services does not include either specifically or by implication any
environmental or biological (e.g., mold, fungi, bacteria) assessment of the site or
identification or prevention of pollutants, hazardous materials or conditions. If the owner
is concerned about the potential for such contamination or pollution, other studies
should be undertaken.
Our services and any correspondence are intended for the sole benefit and exclusive use
of our client for specific application to the project discussed and are accomplished in
accordance with generally accepted geotechnical engineering practices with no third-
party beneficiaries intended. Any third-party access to services or correspondence is
solely for information purposes to support the services provided by Terracon to our
client. Reliance upon the services and any work product is limited to our client and is not
intended for third parties. Any use or reliance of the provided information by third
parties is done solely at their own risk. No warranties, either express or implied, are
intended or made.
Site characteristics as provided are for design purposes and not to estimate excavation
cost. Any use of our report in that regard is done at the sole risk of the excavating cost
estimator as there may be variations on the site that are not apparent in the data that
could significantly affect excavation cost. Any parties charged with estimating excavation
costs should seek their own site characterization for specific purposes to obtain the
specific level of detail necessary for costing. Site safety and cost estimating including
excavation support and dewatering requirements/design are the responsibility of others.
Construction and site development have the potential to affect adjacent properties. Such
impacts can include damages due to vibration, modification of groundwater/surface
water flow during construction, foundation movement due to undermining or subsidence
from excavation, as well as noise or air quality concerns. Evaluation of these items on
nearby properties are commonly associated with contractor means and methods and are
not addressed in this report. The owner and contractor should consider a
preconstruction/precondition survey of surrounding development. If changes in the
nature, design, or location of the project are planned, our conclusions and
recommendations shall not be considered valid unless we review the changes and either
verify or modify our conclusions in writing.
Geotechnical Engineering Report
Rexburg Retail Development | Rexburg, Idaho
May 15, 2024 | Terracon Project No. 62245017
Facilities | Environmental | Geotechnical | Materials
Figures
Contents:
GeoModel (2 pages)
Note: All attachments are one page unless noted above.
4,850
4,855
4,860
4,865
4,870
4,875
4,880
4,885
EL
E
V
A
T
I
O
N
(
M
S
L
)
(
f
e
e
t
)
Layering shown on this figure has been developed by the geotechnical
engineer for purposes of modeling the subsurface conditions as
required for the subsequent geotechnical engineering for this project.
Numbers adjacent to soil column indicate depth below ground surface.
NOTES:
B-1 B-2 B-3 B-4 B-5 B-6 B-7 B-8
B-9
B-10 B-11
Legend
This is not a cross section. This is intended to display the Geotechnical Model only. See individual logs for more detailed conditions.
GeoModel - Store and Cross-Dock Areas
N 2nd E and E Moody Road | Rexburg, Idaho
Terracon Project No. 62245017
Rexburg Retail Development
11849 W Executive Dr Ste G
Boise, ID
First Water Observation
Groundwater levels are temporal. The levels shown are representative of
the date and time of our exploration. Significant changes are possible
over time.
Water levels shown are as measured during and/or after drilling. In
some cases, boring advancement methods mask the presence/absence
of groundwater. See individual logs for details.
Sandy Lean Clay
with Gravel
Well-graded Gravel
with silt and sandPoorly-graded
Gravel with Silt and
Sand
Poorly-graded
Gravel with Clay
and SandPoorly-graded Sand
with Gravel
Poorly-graded Sand
with Silt and Gravel
Poorly-graded Sand
with Silt
Poorly-graded
Gravel with Sand
Clayey Sand with
Gravel Sandy Lean Clay
Model Layer Layer Name General Description
1 Lean clay and fat clay with varying amounts of sand and
gravel, and varying degrees of cementation.
3 Gravel with varying amounts of clay, silt, sand, and
cobbles, and varying degrees of cementation.
2 Sand with varying amounts of clay, silt, and gravel.
Clay
Gravel
Sand
1
3
2
21.5
1
3
4
21.5
1
3
2
3
2
29
3.5
5
7.5
20
31.5
1
3
2
2
19
21.5
1
3
2
29
2.5
23
31.5
1
3
2
21.5
1
2
3
2
29
2
4
22
31.5
1
2
3
2
20
21.5
1
3
2
2
19.5
21.5
1
2
3
2
2.5
5
20
21.5
1
3
2
28.5
4
15
31.5
4,858
4,860
4,862
4,864
4,866
4,868
4,870
4,872
4,874
4,876
4,878
4,880
4,882
4,884
4,886
EL
E
V
A
T
I
O
N
(
M
S
L
)
(
f
e
e
t
)
Layering shown on this figure has been developed by the geotechnical
engineer for purposes of modeling the subsurface conditions as
required for the subsequent geotechnical engineering for this project.
Numbers adjacent to soil column indicate depth below ground surface.
NOTES:
B-12
B-13 B-14
B-15
B-16
B-17
B-18
B-19
B-20
B-21
B-22 B-23
TP-24
Legend
This is not a cross section. This is intended to display the Geotechnical Model only. See individual logs for more detailed conditions.
GeoModel - Adjacent Lots, Drive Aisles, and Parking Areas
N 2nd E and E Moody Road | Rexburg, Idaho
Terracon Project No. 62245017
Rexburg Retail Development
11849 W Executive Dr Ste G
Boise, ID
First Water Observation
Groundwater levels are temporal. The levels shown are representative of
the date and time of our exploration. Significant changes are possible
over time.
Water levels shown are as measured during and/or after drilling. In
some cases, boring advancement methods mask the presence/absence
of groundwater. See individual logs for details.
Sandy Lean Clay
with Gravel
Poorly-graded
Gravel with Silt and
SandPoorly-graded
Gravel with Clay
and Sand
Clayey Sand with
Gravel
Poorly-graded
Gravel with Sand
Poorly-graded Sand
with Gravel
Sandy Fat Clay
Poorly-graded Sand
with Clay and
Gravel
Sandy Lean Clay
Model Layer Layer Name General Description
1 Lean clay and fat clay with varying amounts of sand and
gravel, and varying degrees of cementation.
3 Gravel with varying amounts of clay, silt, sand, and
cobbles, and varying degrees of cementation.
2 Sand with varying amounts of clay, silt, and gravel.
Clay
Gravel
Sand
1
3
2
21.5
1
2
3
1.5
4
21.5
1
3
2
21.5
1
3
2.5
6.5
1
3
2
6.5
1
2
2
6.5
1
3
2
6.5
1
3
2
6.5
1
3
2
6.5
1
2
3
2
5
6.5
1
3
2
6.5
1
3
2
6.5
1
3
1.5
4
Geotechnical Engineering Report
Rexburg Retail Development | Rexburg, Idaho
May 15, 2024 | Terracon Project No. 62245017
Facilities | Environmental | Geotechnical | Materials
Attachments
Geotechnical Engineering Report
Rexburg Retail Development | Rexburg, Idaho
May 15, 2024 | Terracon Project No. 62245017
Facilities | Environmental | Geotechnical | Materials
Exploration and Testing Procedures
Field Exploration
Number of Borings and
Test Pits
Approximate Boring
Depth (feet)1 Location
9 borings 21½ to 31½ WinCo Store building
2 borings 21½ to 31½ Cross-dock building
9 borings 6½ Parking areas
3 borings 21½ Adjacent lots
1 test pit 4 Parking / Stormwater
management area
1. Approximate depth below the ground surface at the time of exploration.
Exploration Layout and Elevations: Terracon personnel provided the boring and test
pit layout using handheld GPS equipment (estimated horizontal accuracy of about ±10
feet) and referencing existing site features. Approximate ground surface elevations were
estimated using Google Earth.
Subsurface Exploration Procedures: Borings were advanced with an ATV-mounted
rotary drill rig using continuous flight hollow stem augers. Four samples were obtained
in the upper 10 feet of each boring and at intervals of 5 feet thereafter. In the thin-
walled tube sampling procedure, a thin-walled, seamless steel tube with a sharp cutting
edge was pushed hydraulically into the soil to obtain a relatively undisturbed sample. In
the split-barrel sampling procedure, a standard 2-inch outer diameter split-barrel
sampling spoon was driven into the ground by a 140-pound automatic hammer falling a
distance of 30 inches. The number of blows required to advance the sampling spoon the
last 12 inches of a normal 18-inch penetration is recorded as the Standard Penetration
Test (SPT) resistance value. The SPT resistance values, also referred to as N-values, are
indicated on the boring logs at the test depths. A 3-inch outer diameter. split-barrel
sampling spoon with 2½-inch inner diameter was used for sampling at select locations
and depths. This split-barrel sampling procedure is similar to standard split spoon
sampling procedure; however, blow counts are typically recorded for 6-inch intervals for
a total of 12 inches of penetration. Borings were monitored for groundwater levels
during drilling and sampling. For safety purposes, all borings were backfilled with
bentonite chips and topped with auger cuttings after their completion.
The N-value provides a reasonable estimate of the relative in-place density of non-
cemented sandy type materials. However, the N-value only provides an indication of the
relative stiffness of cohesive materials, since the penetration resistance of these soils
Geotechnical Engineering Report
Rexburg Retail Development | Rexburg, Idaho
May 15, 2024 | Terracon Project No. 62245017
Facilities | Environmental | Geotechnical | Materials
may be affected by the moisture content. Considerable care should be exercised in
interpreting the N-value in gravelly soils, particularly where the size of the gravel
particles exceeds the inside diameter of the sampling spoon.
An automatic SPT hammer was used to advance the split-spoon sampler in the borings
performed on this site. A greater efficiency is typically achieved with the automatic
hammer compared to the conventional safety hammer operated with a cathead and
rope. Published correlations between the SPT values and soil properties are based on the
cathead and rope method. The higher efficiency of the automatic hammer affects the
standard penetration resistance blow count (N-value) by increasing the penetration per
hammer blow over what would be obtained using the cathead and rope method. The
effect of the automatic hammer's efficiency has been considered in the interpretation
and analysis of the subsurface information for this report.
One test pit was dug with an excavator, we observed the soils in the test pit and took
bulk samples from the excavated material. The test pit was used for infiltration rate
testing. Upon completion of infiltration testing, the test pit was backfilled with the
excavated material. The backfill materials were tamped with the excavator bucket during
placement. No other compaction of backfill was performed.
The sampling depths, penetration distances, and other sampling information was
recorded on the field boring logs. The samples were placed in appropriate containers and
taken to our soil laboratory for testing and classification by a geotechnical professional.
Our exploration team prepared field boring logs as part of the drilling operations. These
field logs included visual classifications of the materials observed during drilling and our
interpretation of the subsurface conditions between samples. Final boring logs were
prepared from the field logs. The final boring logs represent the Geotechnical Engineer's
interpretation of the field logs and include modifications based on observations and tests
of the samples in our laboratory.
Laboratory Testing
The project engineer reviewed the field data and assigned laboratory tests. The
laboratory testing program included the following types of tests:
■ Water content
■ Atterberg limits
■ Grain size analysis
■ Chemical analyses – pH, sulfates, chloride ion, electrical resistivity (in progress)
■ Moisture-density relationship
■ Idaho T-8 R-Value
Geotechnical Engineering Report
Rexburg Retail Development | Rexburg, Idaho
May 15, 2024 | Terracon Project No. 62245017
Facilities | Environmental | Geotechnical | Materials
The laboratory testing program included examination of soil samples by an engineer.
Based on the results of our field and laboratory programs, we described and classified
the soil samples in general accordance with the Unified Soil Classification System
Geotechnical Engineering Report
Rexburg Retail Development | Rexburg, Idaho
May 15, 2024 | Terracon Project No. 62245017
Facilities | Environmental | Geotechnical | Materials
Site Location and Exploration Plans
Contents:
Site Location Plan
Exploration Plan
Note: All attachments are one page unless noted above.
Proposal for Geotechnical Engineering Services
Rexburg Retail Development | Rexburg, Idaho
May 15, 2024 | Terracon Proposal No. P62245017
Note to Preparer: This is a large table with outside borders. Just click inside the table
above this text box, then paste your GIS Toolbox image.
When paragraph markers are turned on you may notice a line of hidden text above
and outside the table – please leave that alone. Limit editing to inside the table.
Site Location
DIAGRAM IS FOR GENERAL LOCATION ONLY, AND IS NOT INTENDED FOR CONSTRUCTION PURPOSES MAP PROVIDED BY MICROSOFT BING MAPS
Proposal for Geotechnical Engineering Services
Rexburg Retail Development | Rexburg, Idaho
May 15, 2024 | Terracon Proposal No. P62245017
Facilities | Environmental | Geotechnical | Materials
Exploration Plan
DIAGRAM IS FOR GENERAL LOCATION ONLY, AND IS NOT INTENDED FOR CONSTRUCTION PURPOSES MAP PROVIDED BY MICROSOFT BING MAPS
Exploration and Laboratory Results
Contents:
Boring Logs (B-1 through B-23 and TP-24; 28 pages)
Grain Size Distribution (2 pages)
Moisture Density Relationship
Note: All attachments are one page unless noted above.
4881
4878
4861.5
SANDY LEAN CLAY WITH GRAVEL (CL), dark brown,
soft, till depth about 1-1/2 feet
WELL GRADED GRAVEL WITH CLAY AND SAND
(GW-GC), dark brown and gray, medium dense
POORLY GRADED GRAVEL WITH SILT AND SAND
(GP-GM), tan to black, medium dense
Boring Terminated at 21.5 Feet
Boring Log No. B-1
Wa
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L
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s
De
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(
F
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)
5
10
15
20
Facilities | Environmental | Geotechnical | Materials
Gr
a
p
h
i
c
L
o
g
Mo
d
e
l
L
a
y
e
r
106.5
2.0
5.0
21.5
1.1
1.1
1.5
1
1.4
1.3
1.4
0-1-2
N=3
7-11-11
N=22
6-17-22
11-14-14
N=28
11-16-21
7-14-15
N=29
9-12-20
N 2nd E and E Moody Road | Rexburg, Idaho
Terracon Project No. 62245017 Boise, ID
11849 W Executive Dr Ste G
Drill Rig
CME-750X
Hammer Type
Automatic
Driller
Haz-Tech Drilling, Inc.
Logged by
CM
Boring Started
04-03-2024
Boring Completed
04-03-2024
Abandonment Method
Boring backfilled with bentonite chips and surface
capped with auger cuttings.
Advancement Method
Hollow-stem auger
Notes
Water Level Observations
Groundwater not encountered
See Exploration and Testing Procedures for a description of field and laboratory procedures usedand additional data (If any).
See Supporting Information for explanation of symbols and abbreviations.
Elevation Reference: Elevations were estimated via Google Earth Pro.
Rexburg Retail Development
Sa
m
p
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T
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Pe
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c
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t
Fi
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s
Wa
t
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r
Co
n
t
e
n
t
(
%
)
Elevation: 4883 (Ft.) +/-
Atterberg
Limits
LL-PL-PI
See Exploration PlanLocation:
Latitude: 43.8545° Longitude: -111.7736°
Depth (Ft.)Re
c
o
v
e
r
y
(
F
t
.
)
Id
a
h
o
T
-
8
R-
V
a
l
u
e
Fi
e
l
d
T
e
s
t
Re
s
u
l
t
s
1
3
4880
4862.5
SANDY LEAN CLAY WITH GRAVEL (CL), dark brown,
soft to stiff, till depth about 1-1/2 feet
POORLY GRADED GRAVEL WITH SILT AND SAND
(GP-GM), dark brown and gray, medium dense to
dense
Boring Terminated at 21.5 Feet
Boring Log No. B-2
Wa
t
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L
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Ob
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s
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5
10
15
20
Facilities | Environmental | Geotechnical | Materials
Gr
a
p
h
i
c
L
o
g
Mo
d
e
l
L
a
y
e
r
57
14.7
18.5
40-17-23
4.0
21.5
0.9
0.4
1.2
1
1.5
1.3
1.4
0-1-2
N=3
0-4-5
N=9
13-20-21
10-14-16
N=30
9-15-18
7-15-18
N=33
12-21-26
N 2nd E and E Moody Road | Rexburg, Idaho
Terracon Project No. 62245017 Boise, ID
11849 W Executive Dr Ste G
Drill Rig
CME-750X
Hammer Type
Automatic
Driller
Haz-Tech Drilling, Inc.
Logged by
CM
Boring Started
04-02-2024
Boring Completed
04-02-2024
Abandonment Method
Boring backfilled with bentonite chips and surface
capped with auger cuttings.
Advancement Method
Hollow-stem auger
Notes
Water Level Observations
Groundwater not encountered
See Exploration and Testing Procedures for a description of field and laboratory procedures usedand additional data (If any).
See Supporting Information for explanation of symbols and abbreviations.
Elevation Reference: Elevations were estimated via Google Earth Pro.
Rexburg Retail Development
Sa
m
p
l
e
T
y
p
e
Pe
r
c
e
n
t
Fi
n
e
s
Wa
t
e
r
Co
n
t
e
n
t
(
%
)
Elevation: 4884 (Ft.) +/-
Atterberg
Limits
LL-PL-PI
See Exploration PlanLocation:
Latitude: 43.8545° Longitude: -111.7733°
Depth (Ft.)Re
c
o
v
e
r
y
(
F
t
.
)
Id
a
h
o
T
-
8
R-
V
a
l
u
e
Fi
e
l
d
T
e
s
t
Re
s
u
l
t
s
1
3
4879.5
4878
4875.5
4863
SANDY LEAN CLAY WITH GRAVEL (CL), dark brown,
soft to stiff, till depth about 1-1/2 feet
POORLY GRADED GRAVEL WITH CLAY AND SAND
(GP-GM), dark brown and gray, medium dense
POORLY GRADED SAND WITH GRAVEL (SP), dark
brown and gray, medium dense
POORLY GRADED GRAVEL WITH SILT AND SAND
(GP-GM), dark brown and gray, dense
POORLY GRADED SAND WITH GRAVEL (SP), dark
brown and gray, medium dense, interbedded layers of
sand and gravel
Boring Log No. B-3
Wa
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Facilities | Environmental | Geotechnical | Materials
Gr
a
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d
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L
a
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r
3.5
5.0
7.5
20.0
0.8
1
1.3
1.2
1.4
1.2
1.4
0-1-2
N=3
3-8-12
N=20
10-15-20
13-18-18
N=36
11-23-27
11-17-15
N=32
4-10-21
N 2nd E and E Moody Road | Rexburg, Idaho
Terracon Project No. 62245017 Boise, ID
11849 W Executive Dr Ste G
Drill Rig
CME-750X
Hammer Type
Automatic
Driller
Haz-Tech Drilling, Inc.
Logged by
CM
Boring Started
04-02-2024
Boring Completed
04-02-2024
Abandonment Method
Boring backfilled with bentonite chips and surface
capped with auger cuttings.
Advancement Method
Hollow-stem auger
Notes
Water Level Observations
29 feet while drilling
See Exploration and Testing Procedures for a description of field and laboratory procedures usedand additional data (If any).
See Supporting Information for explanation of symbols and abbreviations.
Elevation Reference: Elevations were estimated via Google Earth Pro.
Rexburg Retail Development
Sa
m
p
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T
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Pe
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c
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t
Fi
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Wa
t
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r
Co
n
t
e
n
t
(
%
)
Elevation: 4883 (Ft.) +/-
Atterberg
Limits
LL-PL-PI
See Exploration PlanLocation:
Latitude: 43.8545° Longitude: -111.7729°
Depth (Ft.)Re
c
o
v
e
r
y
(
F
t
.
)
Id
a
h
o
T
-
8
R-
V
a
l
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Fi
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T
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s
t
Re
s
u
l
t
s
1
3
2
3
2
4851.5
POORLY GRADED SAND WITH GRAVEL (SP), dark
brown and gray, medium dense, interbedded layers of
sand and gravel (continued)
Boring Terminated at 31.5 Feet
Boring Log No. B-3
Wa
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25
30
Facilities | Environmental | Geotechnical | Materials
Gr
a
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L
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Mo
d
e
l
L
a
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e
r
31.5
1.5
1.5
6-10-12
N=22
6-14-19
N 2nd E and E Moody Road | Rexburg, Idaho
Terracon Project No. 62245017 Boise, ID
11849 W Executive Dr Ste G
Drill Rig
CME-750X
Hammer Type
Automatic
Driller
Haz-Tech Drilling, Inc.
Logged by
CM
Boring Started
04-02-2024
Boring Completed
04-02-2024
Abandonment Method
Boring backfilled with bentonite chips and surface
capped with auger cuttings.
Advancement Method
Hollow-stem auger
Notes
Water Level Observations
29 feet while drilling
See Exploration and Testing Procedures for a description of field and laboratory procedures usedand additional data (If any).
See Supporting Information for explanation of symbols and abbreviations.
Elevation Reference: Elevations were estimated via Google Earth Pro.
Rexburg Retail Development
Sa
m
p
l
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T
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p
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Pe
r
c
e
n
t
Fi
n
e
s
Wa
t
e
r
Co
n
t
e
n
t
(
%
)
Elevation: 4883 (Ft.) +/-
Atterberg
Limits
LL-PL-PI
See Exploration PlanLocation:
Latitude: 43.8545° Longitude: -111.7729°
Depth (Ft.)Re
c
o
v
e
r
y
(
F
t
.
)
Id
a
h
o
T
-
8
R-
V
a
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u
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Fi
e
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d
T
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s
t
Re
s
u
l
t
s
2
4881
4878
4864
4861.5
SANDY LEAN CLAY WITH GRAVEL (CL), dark brown,
soft, till depth about 1-1/2 feet
POORLY GRADED GRAVEL WITH CLAY AND SAND
(GP-GC), dark brown and gray, medium dense
POORLY GRADED GRAVEL WITH SILT AND SAND
(GP-GM), dark brown, medium dense to dense
lens of clay
lens of silt
POORLY GRADED SAND WITH SILT AND GRAVEL
(SP-SM), brown, medium dense
Boring Terminated at 21.5 Feet
Boring Log No. B-4
Wa
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10
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20
Facilities | Environmental | Geotechnical | Materials
Gr
a
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L
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Mo
d
e
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L
a
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2.0
5.0
19.0
21.5
0.8
1.1
1.4
1
1.3
1.2
1.5
0-1-2
N=3
5-11-12
N=23
12-23-27
9-9-9
N=18
7-9-14
7-17-18
N=35
8-12-18
N 2nd E and E Moody Road | Rexburg, Idaho
Terracon Project No. 62245017 Boise, ID
11849 W Executive Dr Ste G
Drill Rig
CME-750X
Hammer Type
Automatic
Driller
Haz-Tech Drilling, Inc.
Logged by
CM
Boring Started
04-03-2024
Boring Completed
04-03-2024
Abandonment Method
Boring backfilled with bentonite chips and surface
capped with auger cuttings.
Advancement Method
Hollow-stem auger
Notes
Water Level Observations
Groundwater not encountered
See Exploration and Testing Procedures for a description of field and laboratory procedures usedand additional data (If any).
See Supporting Information for explanation of symbols and abbreviations.
Elevation Reference: Elevations were estimated via Google Earth Pro.
Rexburg Retail Development
Sa
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T
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Pe
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c
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n
t
Fi
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s
Wa
t
e
r
Co
n
t
e
n
t
(
%
)
Elevation: 4883 (Ft.) +/-
Atterberg
Limits
LL-PL-PI
See Exploration PlanLocation:
Latitude: 43.8542° Longitude: -111.7736°
Depth (Ft.)Re
c
o
v
e
r
y
(
F
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.
)
Id
a
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T
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8
R-
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1
3
2
4881.5
4879.5
SANDY LEAN CLAY WITH GRAVEL (CL), dark brown,
very soft, moderately cemented particles, till depth
about 1-1/2 feet
POORLY GRADED GRAVEL WITH CLAY AND SAND
(GP-GC), dark brown and gray, medium dense
POORLY GRADED GRAVEL WITH SILT AND SAND
(GP-GM), dark brown to black, medium dense to
dense
Boring Log No. B-5
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Gr
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2.5
4.5
0.7
0.3
1.4
0.9
1.3
1.2
1.5
0-0-1
N=1
3-5-5
N=10
12-19-21
10-19-20
N=39
9-13-17
5-12-12
N=24
8-18-18
N 2nd E and E Moody Road | Rexburg, Idaho
Terracon Project No. 62245017 Boise, ID
11849 W Executive Dr Ste G
Drill Rig
CME-750X
Hammer Type
Automatic
Driller
Haz-Tech Drilling, Inc.
Logged by
CM
Boring Started
04-02-2024
Boring Completed
04-02-2024
Abandonment Method
Boring backfilled with bentonite chips and surface
capped with auger cuttings.
Advancement Method
Hollow-stem auger
Notes
Water Level Observations
29 feet while drilling
See Exploration and Testing Procedures for a description of field and laboratory procedures usedand additional data (If any).
See Supporting Information for explanation of symbols and abbreviations.
Elevation Reference: Elevations were estimated via Google Earth Pro.
Rexburg Retail Development
Sa
m
p
l
e
T
y
p
e
Pe
r
c
e
n
t
Fi
n
e
s
Wa
t
e
r
Co
n
t
e
n
t
(
%
)
Elevation: 4884 (Ft.) +/-
Atterberg
Limits
LL-PL-PI
See Exploration PlanLocation:
Latitude: 43.8542° Longitude: -111.7732°
Depth (Ft.)Re
c
o
v
e
r
y
(
F
t
.
)
Id
a
h
o
T
-
8
R-
V
a
l
u
e
Fi
e
l
d
T
e
s
t
Re
s
u
l
t
s
1
3
4861
4852.5
POORLY GRADED SAND WITH SILT (SP-SM), trace
gravel, tan and black, medium dense
Boring Terminated at 31.5 Feet
Boring Log No. B-5
Wa
t
e
r
L
e
v
e
l
Ob
s
e
r
v
a
t
i
o
n
s
De
p
t
h
(
F
t
.
)
25
30
Facilities | Environmental | Geotechnical | Materials
Gr
a
p
h
i
c
L
o
g
Mo
d
e
l
L
a
y
e
r
75.9
23.0
31.5
1.5
1.4
8-14-13
N=27
3-8-10
N=18
N 2nd E and E Moody Road | Rexburg, Idaho
Terracon Project No. 62245017 Boise, ID
11849 W Executive Dr Ste G
Drill Rig
CME-750X
Hammer Type
Automatic
Driller
Haz-Tech Drilling, Inc.
Logged by
CM
Boring Started
04-02-2024
Boring Completed
04-02-2024
Abandonment Method
Boring backfilled with bentonite chips and surface
capped with auger cuttings.
Advancement Method
Hollow-stem auger
Notes
Water Level Observations
29 feet while drilling
See Exploration and Testing Procedures for a description of field and laboratory procedures usedand additional data (If any).
See Supporting Information for explanation of symbols and abbreviations.
Elevation Reference: Elevations were estimated via Google Earth Pro.
Rexburg Retail Development
Sa
m
p
l
e
T
y
p
e
Pe
r
c
e
n
t
Fi
n
e
s
Wa
t
e
r
Co
n
t
e
n
t
(
%
)
Elevation: 4884 (Ft.) +/-
Atterberg
Limits
LL-PL-PI
See Exploration PlanLocation:
Latitude: 43.8542° Longitude: -111.7732°
Depth (Ft.)Re
c
o
v
e
r
y
(
F
t
.
)
Id
a
h
o
T
-
8
R-
V
a
l
u
e
Fi
e
l
d
T
e
s
t
Re
s
u
l
t
s
3
2
4881
4878
4863
4861.5
SANDY LEAN CLAY WITH GRAVEL (CL), dark brown,
soft, till depth about 1-1/2 feet
POORLY GRADED GRAVEL WITH SILT AND SAND
(GP-GM), dark brown and gray, medium dense
POORLY GRADED GRAVEL WITH SAND (GP), dark
brown and gray, dense
with lenses of clay
POORLY GRADED GRAVEL WITH CLAY AND SAND
(GP-GC), dark brown and gray, medium dense
Boring Terminated at 21.5 Feet
Boring Log No. B-6
Wa
t
e
r
L
e
v
e
l
Ob
s
e
r
v
a
t
i
o
n
s
De
p
t
h
(
F
t
.
)
5
10
15
20
Facilities | Environmental | Geotechnical | Materials
Gr
a
p
h
i
c
L
o
g
Mo
d
e
l
L
a
y
e
r
2.0
5.0
20.0
21.5
0.7
0.9
1.4
1.1
1.3
1
1.3
0-1-2
N=3
6-12-12
N=24
12-27-27
8-19-14
N=33
7-26-37
10-16-14
N=30
7-12-13
N 2nd E and E Moody Road | Rexburg, Idaho
Terracon Project No. 62245017 Boise, ID
11849 W Executive Dr Ste G
Drill Rig
CME-750X
Hammer Type
Automatic
Driller
Haz-Tech Drilling, Inc.
Logged by
CM
Boring Started
04-02-2024
Boring Completed
04-02-2024
Abandonment Method
Boring backfilled with bentonite chips and surface
capped with auger cuttings.
Advancement Method
Hollow-stem auger
Notes
Water Level Observations
Groundwater not encountered
See Exploration and Testing Procedures for a description of field and laboratory procedures usedand additional data (If any).
See Supporting Information for explanation of symbols and abbreviations.
Elevation Reference: Elevations were estimated via Google Earth Pro.
Rexburg Retail Development
Sa
m
p
l
e
T
y
p
e
Pe
r
c
e
n
t
Fi
n
e
s
Wa
t
e
r
Co
n
t
e
n
t
(
%
)
Elevation: 4883 (Ft.) +/-
Atterberg
Limits
LL-PL-PI
See Exploration PlanLocation:
Latitude: 43.8542° Longitude: -111.7728°
Depth (Ft.)Re
c
o
v
e
r
y
(
F
t
.
)
Id
a
h
o
T
-
8
R-
V
a
l
u
e
Fi
e
l
d
T
e
s
t
Re
s
u
l
t
s
1
3
4881
4879
4861
SANDY LEAN CLAY WITH GRAVEL (CL), dark brown,
soft, till depth about 1-1/2 feet
CLAYEY SAND WITH GRAVEL (SC), dark brown to
brown, loose
POORLY GRADED GRAVEL WITH SILT AND SAND
(GP-GM), dark brown with orange, medium dense
clay lenses
Boring Log No. B-7
Wa
t
e
r
L
e
v
e
l
Ob
s
e
r
v
a
t
i
o
n
s
De
p
t
h
(
F
t
.
)
5
10
15
20
Facilities | Environmental | Geotechnical | Materials
Gr
a
p
h
i
c
L
o
g
Mo
d
e
l
L
a
y
e
r
2210.9
0-1-2
N=3
1-3-5
N=8
13-16-18
3-7-7
N=14
7-16-19
7-12-14
N=26
5-12-18
2.0
4.0
22.0
0.6
0.9
1.3
1.1
1.3
1.1
1.4
N 2nd E and E Moody Road | Rexburg, Idaho
Terracon Project No. 62245017 Boise, ID
11849 W Executive Dr Ste G
Drill Rig
CME-750X
Hammer Type
Automatic
Driller
Haz-Tech Drilling, Inc.
Logged by
CM
Boring Started
04-03-2024
Boring Completed
04-03-2024
Abandonment Method
Boring backfilled with bentonite chips and surface
capped with auger cuttings.
Advancement Method
Hollow-stem auger
Notes
Water Level Observations
29 feet while drilling
See Exploration and Testing Procedures for a description of field and laboratory procedures usedand additional data (If any).
See Supporting Information for explanation of symbols and abbreviations.
Elevation Reference: Elevations were estimated via Google Earth Pro.
Rexburg Retail Development
Sa
m
p
l
e
T
y
p
e
Pe
r
c
e
n
t
Fi
n
e
s
Wa
t
e
r
Co
n
t
e
n
t
(
%
)
Elevation: 4883 (Ft.) +/-
Atterberg
Limits
LL-PL-PI
See Exploration PlanLocation:
Latitude: 43.8538° Longitude: -111.7735°
Fi
e
l
d
T
e
s
t
Re
s
u
l
t
s
Depth (Ft.)Re
c
o
v
e
r
y
(
F
t
.
)
Id
a
h
o
T
-
8
R-
V
a
l
u
e
1
2
3
4851.5
POORLY GRADED SAND WITH SILT AND GRAVEL
(SP-SM), grayish brown to black, medium dense to
dense
Boring Terminated at 31.5 Feet
Boring Log No. B-7
Wa
t
e
r
L
e
v
e
l
Ob
s
e
r
v
a
t
i
o
n
s
De
p
t
h
(
F
t
.
)
25
30
Facilities | Environmental | Geotechnical | Materials
Gr
a
p
h
i
c
L
o
g
Mo
d
e
l
L
a
y
e
r
12-14-16
N=30
4-6-9
N=15
31.5
1.2
1.1
N 2nd E and E Moody Road | Rexburg, Idaho
Terracon Project No. 62245017 Boise, ID
11849 W Executive Dr Ste G
Drill Rig
CME-750X
Hammer Type
Automatic
Driller
Haz-Tech Drilling, Inc.
Logged by
CM
Boring Started
04-03-2024
Boring Completed
04-03-2024
Abandonment Method
Boring backfilled with bentonite chips and surface
capped with auger cuttings.
Advancement Method
Hollow-stem auger
Notes
Water Level Observations
29 feet while drilling
See Exploration and Testing Procedures for a description of field and laboratory procedures usedand additional data (If any).
See Supporting Information for explanation of symbols and abbreviations.
Elevation Reference: Elevations were estimated via Google Earth Pro.
Rexburg Retail Development
Sa
m
p
l
e
T
y
p
e
Pe
r
c
e
n
t
Fi
n
e
s
Wa
t
e
r
Co
n
t
e
n
t
(
%
)
Elevation: 4883 (Ft.) +/-
Atterberg
Limits
LL-PL-PI
See Exploration PlanLocation:
Latitude: 43.8538° Longitude: -111.7735°
Fi
e
l
d
T
e
s
t
Re
s
u
l
t
s
Depth (Ft.)Re
c
o
v
e
r
y
(
F
t
.
)
Id
a
h
o
T
-
8
R-
V
a
l
u
e
2
4881
4863
4861.5
SANDY LEAN CLAY WITH GRAVEL (CL), dark brown,
soft, till depth about 1-1/2 feet
POORLY GRADED GRAVEL WITH SAND (GP), dark
brown and gray, medium dense to dense
POORLY GRADED SAND WITH GRAVEL (SP), grayish
brown, loose
Boring Terminated at 21.5 Feet
Boring Log No. B-8
Wa
t
e
r
L
e
v
e
l
Ob
s
e
r
v
a
t
i
o
n
s
De
p
t
h
(
F
t
.
)
5
10
15
20
Facilities | Environmental | Geotechnical | Materials
Gr
a
p
h
i
c
L
o
g
Mo
d
e
l
L
a
y
e
r
2.0
20.0
21.5
0.5
0.8
1.3
1
1.5
0.5
1.5
0-1-2
N=3
2-9-12
N=21
11-19-26
12-13-13
N=26
6-13-18
10-21-20
N=41
3-7-7
N 2nd E and E Moody Road | Rexburg, Idaho
Terracon Project No. 62245017 Boise, ID
11849 W Executive Dr Ste G
Drill Rig
CME-750X
Hammer Type
Automatic
Driller
Haz-Tech Drilling, Inc.
Logged by
CM
Boring Started
04-02-2024
Boring Completed
04-02-2024
Abandonment Method
Boring backfilled with bentonite chips and surface
capped with auger cuttings.
Advancement Method
Hollow-stem auger
Notes
Water Level Observations
Groundwater not encountered
See Exploration and Testing Procedures for a description of field and laboratory procedures usedand additional data (If any).
See Supporting Information for explanation of symbols and abbreviations.
Elevation Reference: Elevations were estimated via Google Earth Pro.
Rexburg Retail Development
Sa
m
p
l
e
T
y
p
e
Pe
r
c
e
n
t
Fi
n
e
s
Wa
t
e
r
Co
n
t
e
n
t
(
%
)
Elevation: 4883 (Ft.) +/-
Atterberg
Limits
LL-PL-PI
See Exploration PlanLocation:
Latitude: 43.8538° Longitude: -111.7732°
Depth (Ft.)Re
c
o
v
e
r
y
(
F
t
.
)
Id
a
h
o
T
-
8
R-
V
a
l
u
e
Fi
e
l
d
T
e
s
t
Re
s
u
l
t
s
1
2
3
4880
4862.5
4860.5
SANDY LEAN CLAY WITH GRAVEL (CL), dark brown,
soft, till depth about 1-1/2 feet
POORLY GRADED GRAVEL WITH SAND (GP), dark
brown and gray, medium dense to dense, lenses of
clay from about 2 to 5 feet
POORLY GRADED SAND WITH SILT AND GRAVEL
(SP-SM), dark brown and gray, medium dense, lens
of clay
Boring Terminated at 21.5 Feet
Boring Log No. B-9
Wa
t
e
r
L
e
v
e
l
Ob
s
e
r
v
a
t
i
o
n
s
De
p
t
h
(
F
t
.
)
5
10
15
20
Facilities | Environmental | Geotechnical | Materials
Gr
a
p
h
i
c
L
o
g
Mo
d
e
l
L
a
y
e
r
2.0
19.5
21.5
0.7
1.1
1.2
1
1.1
0.9
1.5
<50-1-1
N=2
2-5-10
N=15
10-22-24
6-13-12
N=25
8-22-25
9-18-16
N=34
9-17-18
N 2nd E and E Moody Road | Rexburg, Idaho
Terracon Project No. 62245017 Boise, ID
11849 W Executive Dr Ste G
Drill Rig
CME-750X
Hammer Type
Automatic
Driller
Haz-Tech Drilling, Inc.
Logged by
CM
Boring Started
04-02-2024
Boring Completed
04-02-2024
Abandonment Method
Boring backfilled with bentonite chips and surface
capped with auger cuttings.
Advancement Method
Hollow-stem auger
Notes
Water Level Observations
Groundwater not encountered
See Exploration and Testing Procedures for a description of field and laboratory procedures usedand additional data (If any).
See Supporting Information for explanation of symbols and abbreviations.
Elevation Reference: Elevations were estimated via Google Earth Pro.
Rexburg Retail Development
Sa
m
p
l
e
T
y
p
e
Pe
r
c
e
n
t
Fi
n
e
s
Wa
t
e
r
Co
n
t
e
n
t
(
%
)
Elevation: 4882 (Ft.) +/-
Atterberg
Limits
LL-PL-PI
See Exploration PlanLocation:
Latitude: 43.8538° Longitude: -111.7729°
Depth (Ft.)Re
c
o
v
e
r
y
(
F
t
.
)
Id
a
h
o
T
-
8
R-
V
a
l
u
e
Fi
e
l
d
T
e
s
t
Re
s
u
l
t
s
1
3
2
4881.5
4879
4869
4864
4862.5
SANDY LEAN CLAY WITH GRAVEL (CL), dark brown,
soft, till depth about 1-1/2 feet
CLAYEY SAND WITH GRAVEL (SC), dark brown and
gray, medium dense
POORLY GRADED GRAVEL WITH SAND (GP), dark
brown and gray, medium dense to dense
POORLY GRADED GRAVEL WITH CLAY AND SAND
(GP-GC), dark brown, dense
POORLY GRADED SAND WITH SILT (SP-SM), trace
gravel, tan and black, medium dense
Boring Terminated at 21.5 Feet
Boring Log No. B-10
Wa
t
e
r
L
e
v
e
l
Ob
s
e
r
v
a
t
i
o
n
s
De
p
t
h
(
F
t
.
)
5
10
15
20
Facilities | Environmental | Geotechnical | Materials
Gr
a
p
h
i
c
L
o
g
Mo
d
e
l
L
a
y
e
r
5
8.3
5.4
32-17-15
2.5
5.0
15.0
20.0
21.5
0.6
1
1.3
1
1.3
0.9
1.5
0-1-2
N=3
3-3-9
N=12
14-29-27
6-12-12
N=24
12-18-17
9-19-17
N=36
9-15-19
N 2nd E and E Moody Road | Rexburg, Idaho
Terracon Project No. 62245017 Boise, ID
11849 W Executive Dr Ste G
Drill Rig
CME-750X
Hammer Type
Automatic
Driller
Haz-Tech Drilling, Inc.
Logged by
CM
Boring Started
04-01-2024
Boring Completed
04-01-2024
Abandonment Method
Boring backfilled with bentonite chips and surface
capped with auger cuttings.
Advancement Method
Hollow-stem auger
Notes
Water Level Observations
Groundwater not encountered
See Exploration and Testing Procedures for a description of field and laboratory procedures usedand additional data (If any).
See Supporting Information for explanation of symbols and abbreviations.
Elevation Reference: Elevations were estimated via Google Earth Pro.
Rexburg Retail Development
Sa
m
p
l
e
T
y
p
e
Pe
r
c
e
n
t
Fi
n
e
s
Wa
t
e
r
Co
n
t
e
n
t
(
%
)
Elevation: 4884 (Ft.) +/-
Atterberg
Limits
LL-PL-PI
See Exploration PlanLocation:
Latitude: 43.8534° Longitude: -111.7728°
Depth (Ft.)Re
c
o
v
e
r
y
(
F
t
.
)
Id
a
h
o
T
-
8
R-
V
a
l
u
e
Fi
e
l
d
T
e
s
t
Re
s
u
l
t
s
1
2
3
2
4879
4868
4863.5
SANDY LEAN CLAY (CL), trace gravel, dark brown,
soft to stiff, till depth about 1-1/2 feet
POORLY GRADED GRAVEL WITH SAND (GP), brown
and gray, medium dense
POORLY GRADED SAND WITH SILT AND GRAVEL
(SP-SM), brown and gray, medium dense
POORLY GRADED SAND WITH GRAVEL (SP), brown,
medium dense
Boring Log No. B-11
Wa
t
e
r
L
e
v
e
l
Ob
s
e
r
v
a
t
i
o
n
s
De
p
t
h
(
F
t
.
)
5
10
15
20
Facilities | Environmental | Geotechnical | Materials
Gr
a
p
h
i
c
L
o
g
Mo
d
e
l
L
a
y
e
r
62
17.9
18.1
41-19-22
4.0
15.0
19.5
0.5
0.5
1.2
0.6
1.2
1
1.5
0-1-3
N=4
1-5-5
N=10
9-14-14
5-9-9
N=18
5-11-13
9-16-11
N=27
10-15-19
N 2nd E and E Moody Road | Rexburg, Idaho
Terracon Project No. 62245017 Boise, ID
11849 W Executive Dr Ste G
Drill Rig
CME-750X
Hammer Type
Automatic
Driller
Haz-Tech Drilling, Inc.
Logged by
CM
Boring Started
04-02-2024
Boring Completed
04-02-2024
Abandonment Method
Boring backfilled with bentonite chips and surface
capped with auger cuttings.
Advancement Method
Hollow-stem auger
Notes
Water Level Observations
28.5 feet while drilling
See Exploration and Testing Procedures for a description of field and laboratory procedures usedand additional data (If any).
See Supporting Information for explanation of symbols and abbreviations.
Elevation Reference: Elevations were estimated via Google Earth Pro.
Rexburg Retail Development
Sa
m
p
l
e
T
y
p
e
Pe
r
c
e
n
t
Fi
n
e
s
Wa
t
e
r
Co
n
t
e
n
t
(
%
)
Elevation: 4883 (Ft.) +/-
Atterberg
Limits
LL-PL-PI
See Exploration PlanLocation:
Latitude: 43.8533° Longitude: -111.7724°
Depth (Ft.)Re
c
o
v
e
r
y
(
F
t
.
)
Id
a
h
o
T
-
8
R-
V
a
l
u
e
Fi
e
l
d
T
e
s
t
Re
s
u
l
t
s
1
3
2
4851.5
POORLY GRADED SAND WITH GRAVEL (SP), brown,
medium dense (continued)
Boring Terminated at 31.5 Feet
Boring Log No. B-11
Wa
t
e
r
L
e
v
e
l
Ob
s
e
r
v
a
t
i
o
n
s
De
p
t
h
(
F
t
.
)
25
30
Facilities | Environmental | Geotechnical | Materials
Gr
a
p
h
i
c
L
o
g
Mo
d
e
l
L
a
y
e
r
31.5
1.3
1
4-9-11
N=20
3-8-10
N=18
N 2nd E and E Moody Road | Rexburg, Idaho
Terracon Project No. 62245017 Boise, ID
11849 W Executive Dr Ste G
Drill Rig
CME-750X
Hammer Type
Automatic
Driller
Haz-Tech Drilling, Inc.
Logged by
CM
Boring Started
04-02-2024
Boring Completed
04-02-2024
Abandonment Method
Boring backfilled with bentonite chips and surface
capped with auger cuttings.
Advancement Method
Hollow-stem auger
Notes
Water Level Observations
28.5 feet while drilling
See Exploration and Testing Procedures for a description of field and laboratory procedures usedand additional data (If any).
See Supporting Information for explanation of symbols and abbreviations.
Elevation Reference: Elevations were estimated via Google Earth Pro.
Rexburg Retail Development
Sa
m
p
l
e
T
y
p
e
Pe
r
c
e
n
t
Fi
n
e
s
Wa
t
e
r
Co
n
t
e
n
t
(
%
)
Elevation: 4883 (Ft.) +/-
Atterberg
Limits
LL-PL-PI
See Exploration PlanLocation:
Latitude: 43.8533° Longitude: -111.7724°
Depth (Ft.)Re
c
o
v
e
r
y
(
F
t
.
)
Id
a
h
o
T
-
8
R-
V
a
l
u
e
Fi
e
l
d
T
e
s
t
Re
s
u
l
t
s
2
4879
4871
4866
4859.5
SANDY LEAN CLAY WITH GRAVEL (CL), dark brown,
soft to medium stiff, till depth about 1-1/2 feet
POORLY GRADED GRAVEL WITH SILT AND SAND
(GP-GM), dark brown to black, medium dense to
dense, lenses of clay from about 2 to 5 feet
POORLY GRADED GRAVEL WITH CLAY AND SAND
(GP-GC), brown and dark gray, very dense
POORLY GRADED GRAVEL WITH SILT AND SAND
(GP-GM), tan to dark brown with black, medium
dense to dense
Boring Terminated at 21.5 Feet
Boring Log No. B-12
Wa
t
e
r
L
e
v
e
l
Ob
s
e
r
v
a
t
i
o
n
s
De
p
t
h
(
F
t
.
)
5
10
15
20
Facilities | Environmental | Geotechnical | Materials
Gr
a
p
h
i
c
L
o
g
Mo
d
e
l
L
a
y
e
r
2.0
10.0
15.0
21.5
0.5
0.8
0.9
1.2
1
1.3
1.2
1-2-2
N=4
3-4-11
N=15
9-15-21
N=36
10-24-24
10-27-35
N=62
8-18-25
4-18-20
N=38
N 2nd E and E Moody Road | Rexburg, Idaho
Terracon Project No. 62245017 Boise, ID
11849 W Executive Dr Ste G
Drill Rig
CME-750X
Hammer Type
Automatic
Driller
Haz-Tech Drilling, Inc.
Logged by
CM
Boring Started
04-01-2024
Boring Completed
04-01-2024
Abandonment Method
Boring backfilled with bentonite chips and surface
capped with auger cuttings.
Advancement Method
Hollow-stem auger
Notes
Water Level Observations
Groundwater not encountered
See Exploration and Testing Procedures for a description of field and laboratory procedures usedand additional data (If any).
See Supporting Information for explanation of symbols and abbreviations.
Elevation Reference: Elevations were estimated via Google Earth Pro.
Rexburg Retail Development
Sa
m
p
l
e
T
y
p
e
Pe
r
c
e
n
t
Fi
n
e
s
Wa
t
e
r
Co
n
t
e
n
t
(
%
)
Elevation: 4881 (Ft.) +/-
Atterberg
Limits
LL-PL-PI
See Exploration PlanLocation:
Latitude: 43.8538° Longitude: -111.7774°
Depth (Ft.)Re
c
o
v
e
r
y
(
F
t
.
)
Id
a
h
o
T
-
8
R-
V
a
l
u
e
Fi
e
l
d
T
e
s
t
Re
s
u
l
t
s
1
3
4880.5
4878
4872
4867
4860.5
SANDY LEAN CLAY WITH GRAVEL (CL), dark brown,
soft, till depth about 1-1/2 feet
CLAYEY SAND WITH GRAVEL (SC), brown, medium
dense, weakly cemented particles
POORLY GRADED GRAVEL WITH SILT AND SAND
(GP-GM), dark brown to black, medium dense to
dense
POORLY GRADED GRAVEL WITH CLAY AND SAND
(GP-GC), black and orange, medium dense
POORLY GRADED GRAVEL WITH SILT AND SAND
(GP-GM), brown and black with orange, medium
dense to dense
Boring Terminated at 21.5 Feet
Boring Log No. B-13
Wa
t
e
r
L
e
v
e
l
Ob
s
e
r
v
a
t
i
o
n
s
De
p
t
h
(
F
t
.
)
5
10
15
20
Facilities | Environmental | Geotechnical | Materials
Gr
a
p
h
i
c
L
o
g
Mo
d
e
l
L
a
y
e
r
1.5
4.0
10.0
15.0
21.5
0.7
0.8
1.3
1.1
1.5
1
1.4
0-1-1
N=2
2-5-7
N=12
11-17-24
12-16-17
N=33
12-15-18
8-22-17
N=39
8-9-10
N 2nd E and E Moody Road | Rexburg, Idaho
Terracon Project No. 62245017 Boise, ID
11849 W Executive Dr Ste G
Drill Rig
CME-750X
Hammer Type
Automatic
Driller
Haz-Tech Drilling, Inc.
Logged by
CM
Boring Started
04-03-2024
Boring Completed
04-03-2024
Abandonment Method
Boring backfilled with bentonite chips and surface
capped with auger cuttings.
Advancement Method
Hollow-stem auger
Notes
Water Level Observations
Groundwater not encountered
See Exploration and Testing Procedures for a description of field and laboratory procedures usedand additional data (If any).
See Supporting Information for explanation of symbols and abbreviations.
Elevation Reference: Elevations were estimated via Google Earth Pro.
Rexburg Retail Development
Sa
m
p
l
e
T
y
p
e
Pe
r
c
e
n
t
Fi
n
e
s
Wa
t
e
r
Co
n
t
e
n
t
(
%
)
Elevation: 4882 (Ft.) +/-
Atterberg
Limits
LL-PL-PI
See Exploration PlanLocation:
Latitude: 43.8538° Longitude: -111.7760°
Depth (Ft.)Re
c
o
v
e
r
y
(
F
t
.
)
Id
a
h
o
T
-
8
R-
V
a
l
u
e
Fi
e
l
d
T
e
s
t
Re
s
u
l
t
s
1
2
3
4880
4877
4872
4867
4860.5
SANDY LEAN CLAY WITH GRAVEL (CL), dark brown,
soft, till depth about 1-1/2 feet
POORLY GRADED GRAVEL WITH CLAY AND SAND
(GP-GC), brown to black, medium dense
POORLY GRADED GRAVEL WITH SILT AND SAND
(GP-GM), dark brown to black, medium dense
POORLY GRADED GRAVEL WITH CLAY AND SAND
(GP-GC), black and orange, medium dense
POORLY GRADED GRAVEL WITH SILT AND SAND
(GP-GM), dark brown to black, medium dense
Boring Terminated at 21.5 Feet
Boring Log No. B-14
Wa
t
e
r
L
e
v
e
l
Ob
s
e
r
v
a
t
i
o
n
s
De
p
t
h
(
F
t
.
)
5
10
15
20
Facilities | Environmental | Geotechnical | Materials
Gr
a
p
h
i
c
L
o
g
Mo
d
e
l
L
a
y
e
r
2.0
5.0
10.0
15.0
21.5
0.5
1.1
1.3
1
1.2
1
1.3
0-0-2
N=2
4-10-12
N=22
4-13-24
7-12-12
N=24
7-13-15
6-12-12
N=24
13-18-19
N 2nd E and E Moody Road | Rexburg, Idaho
Terracon Project No. 62245017 Boise, ID
11849 W Executive Dr Ste G
Drill Rig
CME-750X
Hammer Type
Automatic
Driller
Haz-Tech Drilling, Inc.
Logged by
CM
Boring Started
04-01-2024
Boring Completed
04-01-2024
Abandonment Method
Boring backfilled with bentonite chips and surface
capped with auger cuttings.
Advancement Method
Hollow-stem auger
Notes
Water Level Observations
Groundwater not encountered
See Exploration and Testing Procedures for a description of field and laboratory procedures usedand additional data (If any).
See Supporting Information for explanation of symbols and abbreviations.
Elevation Reference: Elevations were estimated via Google Earth Pro.
Rexburg Retail Development
Sa
m
p
l
e
T
y
p
e
Pe
r
c
e
n
t
Fi
n
e
s
Wa
t
e
r
Co
n
t
e
n
t
(
%
)
Elevation: 4882 (Ft.) +/-
Atterberg
Limits
LL-PL-PI
See Exploration PlanLocation:
Latitude: 43.8528° Longitude: -111.7774°
Depth (Ft.)Re
c
o
v
e
r
y
(
F
t
.
)
Id
a
h
o
T
-
8
R-
V
a
l
u
e
Fi
e
l
d
T
e
s
t
Re
s
u
l
t
s
1
3
4882.5
4878.5
SANDY LEAN CLAY WITH GRAVEL (CL), dark brown,
soft, till depth about 1-1/2 feet
POORLY GRADED GRAVEL WITH SAND (GP), brown
to dark brown and gray, medium dense
Boring Terminated at 6.5 Feet
Boring Log No. B-15
Wa
t
e
r
L
e
v
e
l
Ob
s
e
r
v
a
t
i
o
n
s
De
p
t
h
(
F
t
.
)
5
Facilities | Environmental | Geotechnical | Materials
Gr
a
p
h
i
c
L
o
g
Mo
d
e
l
L
a
y
e
r
53.6
2.5
6.5
0.5
0.9
1.4
0-0-2
N=2
7-11-13
N=24
11-14-17
N 2nd E and E Moody Road | Rexburg, Idaho
Terracon Project No. 62245017 Boise, ID
11849 W Executive Dr Ste G
Drill Rig
CME-750X
Hammer Type
Automatic
Driller
Haz-Tech Drilling, Inc.
Logged by
CM
Boring Started
04-03-2024
Boring Completed
04-03-2024
Abandonment Method
Boring backfilled with auger cuttings.
Advancement Method
Hollow-stem auger
Notes
Water Level Observations
Groundwater not encountered
See Exploration and Testing Procedures for a description of field and laboratory procedures usedand additional data (If any).
See Supporting Information for explanation of symbols and abbreviations.
Elevation Reference: Elevations were estimated via Google Earth Pro.
Rexburg Retail Development
Sa
m
p
l
e
T
y
p
e
Pe
r
c
e
n
t
Fi
n
e
s
Wa
t
e
r
Co
n
t
e
n
t
(
%
)
Elevation: 4885 (Ft.) +/-
Atterberg
Limits
LL-PL-PI
See Exploration PlanLocation:
Latitude: 43.8546° Longitude: -111.7747°
Depth (Ft.)Re
c
o
v
e
r
y
(
F
t
.
)
Id
a
h
o
T
-
8
R-
V
a
l
u
e
Fi
e
l
d
T
e
s
t
Re
s
u
l
t
s
1
3
4882
4877.5
SANDY LEAN CLAY WITH GRAVEL (CL), dark brown,
soft, till depth about 1-1/2 feet
POORLY GRADED GRAVEL WITH SAND (GP), brown
to dark brown and gray, medium dense to dense
Boring Terminated at 6.5 Feet
Boring Log No. B-16
Wa
t
e
r
L
e
v
e
l
Ob
s
e
r
v
a
t
i
o
n
s
De
p
t
h
(
F
t
.
)
5
Facilities | Environmental | Geotechnical | Materials
Gr
a
p
h
i
c
L
o
g
Mo
d
e
l
L
a
y
e
r
2.0
6.5
0.8
0.9
1.5
0-1-2
N=3
8-16-16
N=32
13-19-25
N 2nd E and E Moody Road | Rexburg, Idaho
Terracon Project No. 62245017 Boise, ID
11849 W Executive Dr Ste G
Drill Rig
CME-750X
Hammer Type
Automatic
Driller
Haz-Tech Drilling, Inc.
Logged by
CM
Boring Started
04-03-2024
Boring Completed
04-03-2024
Abandonment Method
Boring backfilled with auger cuttings.
Advancement Method
Hollow-stem auger
Notes
Water Level Observations
Groundwater not encountered
See Exploration and Testing Procedures for a description of field and laboratory procedures usedand additional data (If any).
See Supporting Information for explanation of symbols and abbreviations.
Elevation Reference: Elevations were estimated via Google Earth Pro.
Rexburg Retail Development
Sa
m
p
l
e
T
y
p
e
Pe
r
c
e
n
t
Fi
n
e
s
Wa
t
e
r
Co
n
t
e
n
t
(
%
)
Elevation: 4884 (Ft.) +/-
Atterberg
Limits
LL-PL-PI
See Exploration PlanLocation:
Latitude: 43.8546° Longitude: -111.7741°
Depth (Ft.)Re
c
o
v
e
r
y
(
F
t
.
)
Id
a
h
o
T
-
8
R-
V
a
l
u
e
Fi
e
l
d
T
e
s
t
Re
s
u
l
t
s
1
3
4883
4878.5
SANDY LEAN CLAY WITH GRAVEL (CL), with
organics, dark brown, soft, till depth about 1-1/2 feet
POORLY GRADED SAND WITH GRAVEL (SP), dark
brown and gray, medium dense
Boring Terminated at 6.5 Feet
Boring Log No. B-17
Wa
t
e
r
L
e
v
e
l
Ob
s
e
r
v
a
t
i
o
n
s
De
p
t
h
(
F
t
.
)
5
Facilities | Environmental | Geotechnical | Materials
Gr
a
p
h
i
c
L
o
g
Mo
d
e
l
L
a
y
e
r
2.0
6.5
0.8
1.2
1.3
0-1-2
N=3
5-9-13
N=22
15-22-24
N 2nd E and E Moody Road | Rexburg, Idaho
Terracon Project No. 62245017 Boise, ID
11849 W Executive Dr Ste G
Drill Rig
CME-750X
Hammer Type
Automatic
Driller
Haz-Tech Drilling, Inc.
Logged by
CM
Boring Started
04-02-2024
Boring Completed
04-02-2024
Abandonment Method
Boring backfilled with auger cuttings.
Advancement Method
Hollow-stem auger
Notes
Water Level Observations
Groundwater not encountered
See Exploration and Testing Procedures for a description of field and laboratory procedures usedand additional data (If any).
See Supporting Information for explanation of symbols and abbreviations.
Elevation Reference: Elevations were estimated via Google Earth Pro.
Rexburg Retail Development
Sa
m
p
l
e
T
y
p
e
Pe
r
c
e
n
t
Fi
n
e
s
Wa
t
e
r
Co
n
t
e
n
t
(
%
)
Elevation: 4885 (Ft.) +/-
Atterberg
Limits
LL-PL-PI
See Exploration PlanLocation:
Latitude: 43.8546° Longitude: -111.7725°
Depth (Ft.)Re
c
o
v
e
r
y
(
F
t
.
)
Id
a
h
o
T
-
8
R-
V
a
l
u
e
Fi
e
l
d
T
e
s
t
Re
s
u
l
t
s
1
2
4881
4876.5
SANDY LEAN CLAY WITH GRAVEL (CL), dark brown,
soft, moderately cemented particles, till depth about
1-1/2 feet
POORLY GRADED GRAVEL WITH SILT AND SAND
(GP-GM), brown to dark brown, medium dense
Boring Terminated at 6.5 Feet
Boring Log No. B-18
Wa
t
e
r
L
e
v
e
l
Ob
s
e
r
v
a
t
i
o
n
s
De
p
t
h
(
F
t
.
)
5
Facilities | Environmental | Geotechnical | Materials
Gr
a
p
h
i
c
L
o
g
Mo
d
e
l
L
a
y
e
r
2.0
6.5
0.7
1
1.4
0-1-1
N=2
4-8-15
N=23
10-21-25
N 2nd E and E Moody Road | Rexburg, Idaho
Terracon Project No. 62245017 Boise, ID
11849 W Executive Dr Ste G
Drill Rig
CME-750X
Hammer Type
Automatic
Driller
Haz-Tech Drilling, Inc.
Logged by
CM
Boring Started
04-03-2024
Boring Completed
04-03-2024
Abandonment Method
Boring backfilled with auger cuttings.
Advancement Method
Hollow-stem auger
Notes
Water Level Observations
Groundwater not encountered
See Exploration and Testing Procedures for a description of field and laboratory procedures usedand additional data (If any).
See Supporting Information for explanation of symbols and abbreviations.
Elevation Reference: Elevations were estimated via Google Earth Pro.
Rexburg Retail Development
Sa
m
p
l
e
T
y
p
e
Pe
r
c
e
n
t
Fi
n
e
s
Wa
t
e
r
Co
n
t
e
n
t
(
%
)
Elevation: 4883 (Ft.) +/-
Atterberg
Limits
LL-PL-PI
See Exploration PlanLocation:
Latitude: 43.8541° Longitude: -111.7752°
Depth (Ft.)Re
c
o
v
e
r
y
(
F
t
.
)
Id
a
h
o
T
-
8
R-
V
a
l
u
e
Fi
e
l
d
T
e
s
t
Re
s
u
l
t
s
1
3
4882
4879
4877.5
SANDY LEAN CLAY WITH GRAVEL (CL), dark brown,
soft, till depth about 1-1/2 feet
POORLY GRADED GRAVEL WITH CLAY AND SAND
(GP-GC), brown and gray, dense, weakly cemented
particles
POORLY GRADED GRAVEL WITH SILT AND SAND
(GP-GM), dark brown to black, medium dense
Boring Terminated at 6.5 Feet
Boring Log No. B-19
Wa
t
e
r
L
e
v
e
l
Ob
s
e
r
v
a
t
i
o
n
s
De
p
t
h
(
F
t
.
)
5
Facilities | Environmental | Geotechnical | Materials
Gr
a
p
h
i
c
L
o
g
Mo
d
e
l
L
a
y
e
r
2.0
5.0
6.5
1
1
1.4
0-1-1
N=2
7-11-22
N=33
8-19-22
N 2nd E and E Moody Road | Rexburg, Idaho
Terracon Project No. 62245017 Boise, ID
11849 W Executive Dr Ste G
Drill Rig
CME-750X
Hammer Type
Automatic
Driller
Haz-Tech Drilling, Inc.
Logged by
CM
Boring Started
04-03-2024
Boring Completed
04-03-2024
Abandonment Method
Boring backfilled with auger cuttings.
Advancement Method
Hollow-stem auger
Notes
Water Level Observations
Groundwater not encountered
See Exploration and Testing Procedures for a description of field and laboratory procedures usedand additional data (If any).
See Supporting Information for explanation of symbols and abbreviations.
Elevation Reference: Elevations were estimated via Google Earth Pro.
Rexburg Retail Development
Sa
m
p
l
e
T
y
p
e
Pe
r
c
e
n
t
Fi
n
e
s
Wa
t
e
r
Co
n
t
e
n
t
(
%
)
Elevation: 4884 (Ft.) +/-
Atterberg
Limits
LL-PL-PI
See Exploration PlanLocation:
Latitude: 43.8541° Longitude: -111.7741°
Depth (Ft.)Re
c
o
v
e
r
y
(
F
t
.
)
Id
a
h
o
T
-
8
R-
V
a
l
u
e
Fi
e
l
d
T
e
s
t
Re
s
u
l
t
s
1
3
4879
4874.5
SANDY FAT CLAY (CH), trace gravel, dark brown,
soft, till depth about 1-1/2 feet
POORLY GRADED GRAVEL WITH SILT AND SAND
(GP-GM), dark brown and gray, medium dense to
dense, lenses of clay
Boring Terminated at 6.5 Feet
Boring Log No. B-20
Wa
t
e
r
L
e
v
e
l
Ob
s
e
r
v
a
t
i
o
n
s
De
p
t
h
(
F
t
.
)
5
Facilities | Environmental | Geotechnical | Materials
Gr
a
p
h
i
c
L
o
g
Mo
d
e
l
L
a
y
e
r
6618.8 57-21-36
2.0
6.5
0.4
1.2
1.4
<5
0-1-1
N=2
6-11-14
N=25
11-23-28
N 2nd E and E Moody Road | Rexburg, Idaho
Terracon Project No. 62245017 Boise, ID
11849 W Executive Dr Ste G
Drill Rig
CME-750X
Hammer Type
Automatic
Driller
Haz-Tech Drilling, Inc.
Logged by
CM
Boring Started
04-01-2024
Boring Completed
04-01-2024
Abandonment Method
Boring backfilled with auger cuttings.
Advancement Method
Hollow-stem auger
Notes
Water Level Observations
Groundwater not encountered
See Exploration and Testing Procedures for a description of field and laboratory proceduresused and additional data (If any).
See Supporting Information for explanation of symbols and abbreviations.
Elevation Reference: Elevations were estimated via Google Earth Pro.
Rexburg Retail Development
Sa
m
p
l
e
T
y
p
e
Pe
r
c
e
n
t
Fi
n
e
s
Wa
t
e
r
Co
n
t
e
n
t
(
%
)
Elevation: 4881 (Ft.) +/-
Atterberg
Limits
LL-PL-PI
See Exploration PlanLocation:
Latitude: 43.8534° Longitude: -111.7765°
Depth (Ft.)Re
c
o
v
e
r
y
(
F
t
.
)
Id
a
h
o
T
-
8
R-
V
a
l
u
e
Fi
e
l
d
T
e
s
t
Re
s
u
l
t
s
1
3
4880
4877
4875.5
SANDY LEAN CLAY WITH GRAVEL (CL), dark brown,
soft, till depth about 1-1/2 feet
POORLY GRADED SAND WITH CLAY AND GRAVEL
(SP-SC), dark brown and gray, medium dense
POORLY GRADED GRAVEL WITH SAND (GP), dark
brown and gray, dense
Boring Terminated at 6.5 Feet
Boring Log No. B-21
Wa
t
e
r
L
e
v
e
l
Ob
s
e
r
v
a
t
i
o
n
s
De
p
t
h
(
F
t
.
)
5
Facilities | Environmental | Geotechnical | Materials
Gr
a
p
h
i
c
L
o
g
Mo
d
e
l
L
a
y
e
r
64.9
2.0
5.0
6.5
0.7
1
1.3
0-1-1
N=2
6-11-13
N=24
12-23-25
N 2nd E and E Moody Road | Rexburg, Idaho
Terracon Project No. 62245017 Boise, ID
11849 W Executive Dr Ste G
Drill Rig
CME-750X
Hammer Type
Automatic
Driller
Haz-Tech Drilling, Inc.
Logged by
CM
Boring Started
04-01-2024
Boring Completed
04-01-2024
Abandonment Method
Boring backfilled with auger cuttings.
Advancement Method
Hollow-stem auger
Notes
Water Level Observations
Groundwater not encountered
See Exploration and Testing Procedures for a description of field and laboratory procedures usedand additional data (If any).
See Supporting Information for explanation of symbols and abbreviations.
Elevation Reference: Elevations were estimated via Google Earth Pro.
Rexburg Retail Development
Sa
m
p
l
e
T
y
p
e
Pe
r
c
e
n
t
Fi
n
e
s
Wa
t
e
r
Co
n
t
e
n
t
(
%
)
Elevation: 4882 (Ft.) +/-
Atterberg
Limits
LL-PL-PI
See Exploration PlanLocation:
Latitude: 43.8535° Longitude: -111.7752°
Depth (Ft.)Re
c
o
v
e
r
y
(
F
t
.
)
Id
a
h
o
T
-
8
R-
V
a
l
u
e
Fi
e
l
d
T
e
s
t
Re
s
u
l
t
s
1
2
3
4881
4876.5
SANDY LEAN CLAY WITH GRAVEL (CL), dark brown,
very soft, till depth about 1-1/2 feet
POORLY GRADED GRAVEL WITH SILT AND SAND
(GP-GM), dark brown and gray, dense
Boring Terminated at 6.5 Feet
Boring Log No. B-22
Wa
t
e
r
L
e
v
e
l
Ob
s
e
r
v
a
t
i
o
n
s
De
p
t
h
(
F
t
.
)
5
Facilities | Environmental | Geotechnical | Materials
Gr
a
p
h
i
c
L
o
g
Mo
d
e
l
L
a
y
e
r
2.0
6.5
0.4
0.8
1.5
0-0-1
N=1
11-20-16
N=36
15-30-31
N 2nd E and E Moody Road | Rexburg, Idaho
Terracon Project No. 62245017 Boise, ID
11849 W Executive Dr Ste G
Drill Rig
CME-750X
Hammer Type
Automatic
Driller
Haz-Tech Drilling, Inc.
Logged by
CM
Boring Started
04-01-2024
Boring Completed
04-01-2024
Abandonment Method
Boring backfilled with auger cuttings.
Advancement Method
Hollow-stem auger
Notes
Water Level Observations
Groundwater not encountered
See Exploration and Testing Procedures for a description of field and laboratory procedures usedand additional data (If any).
See Supporting Information for explanation of symbols and abbreviations.
Elevation Reference: Elevations were estimated via Google Earth Pro.
Rexburg Retail Development
Sa
m
p
l
e
T
y
p
e
Pe
r
c
e
n
t
Fi
n
e
s
Wa
t
e
r
Co
n
t
e
n
t
(
%
)
Elevation: 4883 (Ft.) +/-
Atterberg
Limits
LL-PL-PI
See Exploration PlanLocation:
Latitude: 43.8535° Longitude: -111.7741°
Depth (Ft.)Re
c
o
v
e
r
y
(
F
t
.
)
Id
a
h
o
T
-
8
R-
V
a
l
u
e
Fi
e
l
d
T
e
s
t
Re
s
u
l
t
s
1
3
4881
4876.5
SANDY LEAN CLAY WITH GRAVEL (CL), trace gravel,
dark brown, soft, weakly cemented particles, till depth
about 1-1/2 feet
POORLY GRADED GRAVEL WITH SILT AND SAND
(GP-GM), dark brown and gray, medium dense
Boring Terminated at 6.5 Feet
Boring Log No. B-23
Wa
t
e
r
L
e
v
e
l
Ob
s
e
r
v
a
t
i
o
n
s
De
p
t
h
(
F
t
.
)
5
Facilities | Environmental | Geotechnical | Materials
Gr
a
p
h
i
c
L
o
g
Mo
d
e
l
L
a
y
e
r
2.0
6.5
0.4
0.9
1.2
0-0-2
N=2
6-12-13
N=25
7-15-20
N 2nd E and E Moody Road | Rexburg, Idaho
Terracon Project No. 62245017 Boise, ID
11849 W Executive Dr Ste G
Drill Rig
CME-750X
Hammer Type
Automatic
Driller
Haz-Tech Drilling, Inc.
Logged by
CM
Boring Started
04-01-2024
Boring Completed
04-01-2024
Abandonment Method
Boring backfilled with auger cuttings.
Advancement Method
Hollow-stem auger
Notes
Water Level Observations
Groundwater not encountered
See Exploration and Testing Procedures for a description of field and laboratory procedures usedand additional data (If any).
See Supporting Information for explanation of symbols and abbreviations.
Elevation Reference: Elevations were estimated via Google Earth Pro.
Rexburg Retail Development
Sa
m
p
l
e
T
y
p
e
Pe
r
c
e
n
t
Fi
n
e
s
Wa
t
e
r
Co
n
t
e
n
t
(
%
)
Elevation: 4883 (Ft.) +/-
Atterberg
Limits
LL-PL-PI
See Exploration PlanLocation:
Latitude: 43.8534° Longitude: -111.7734°
Depth (Ft.)Re
c
o
v
e
r
y
(
F
t
.
)
Id
a
h
o
T
-
8
R-
V
a
l
u
e
Fi
e
l
d
T
e
s
t
Re
s
u
l
t
s
1
3
4882.5
4880
SANDY LEAN CLAY (CL), trace gravel, dark brown,
till depth about 1-1/2 feet
POORLY GRADED GRAVEL WITH CLAY AND SAND
(GP-GC), dark brown and gray
Test Pit Terminated at 4 Feet
Test Pit Log No. TP-24
Wa
t
e
r
L
e
v
e
l
Ob
s
e
r
v
a
t
i
o
n
s
De
p
t
h
(
F
t
.
)
Facilities | Environmental | Geotechnical | Materials
Gr
a
p
h
i
c
L
o
g
Mo
d
e
l
L
a
y
e
r
55
6
17.2
1.5
4.0
N 2nd E and E Moody Road | Rexburg, Idaho
Terracon Project No. 62245017 Boise, ID
11849 W Executive Dr Ste G
Excavator
Backhoe
Operator
Precision Underground, LLC
Logged by
CM
Test Pit Started
04-04-2024
Test Pit Completed
04-04-2024
Abandonment Method
Test pit backfilled with soil cuttings upon completion.
Advancement Method
Backhoe
Notes
Water Level Observations
Groundwater not encountered
See Exploration and Testing Procedures for a description of field and laboratory procedures usedand additional data (If any).
See Supporting Information for explanation of symbols and abbreviations.
Elevation Reference: Elevations were estimated via Google Earth Pro.
Rexburg Retail Development
Sa
m
p
l
e
T
y
p
e
Pe
r
c
e
n
t
Fi
n
e
s
Wa
t
e
r
Co
n
t
e
n
t
(
%
)
Elevation: 4884 (Ft.) +/-
Atterberg
Limits
LL-PL-PI
See Exploration PlanLocation:
Latitude: 43.8540° Longitude: -111.7745°
Depth (Ft.)Re
c
o
v
e
r
y
(
F
t
.
)
Id
a
h
o
T
-
8
R-
V
a
l
u
e
Fi
e
l
d
T
e
s
t
Re
s
u
l
t
s
1
3
0
5
10
15
20
25
30
35
40
45
50
55
60
65
70
75
80
85
90
95
100
0.0010.010.1110100
16 2044 100
U.S. Sieve Numbers
632 10 14 506 2001.5 83/4 1/23/8 30 403 601 140
HydrometerU.S. Sieve Opening in Inches
Grain Size Distribution
SandGravel
Grain Size (mm)
coarse fine coarse finemedium Silt or ClayCobbles
Pe
r
c
e
n
t
C
o
a
r
s
e
r
b
y
W
e
i
g
h
t
Pe
r
c
e
n
t
F
i
n
e
r
b
y
W
e
i
g
h
t
100
90
80
70
60
50
40
30
20
10
0
ASTM D422 / ASTM C136 / AASHTO T27
Facilities | Environmental | Geotechnical | Materials
LL PL PI Cc CuDescription
WELL GRADED GRAVEL with CLAY and SAND
POORLY GRADED SAND with SILT and GRAVEL
POORLY GRADED GRAVEL with SAND
POORLY GRADED GRAVEL with SAND
POORLY GRADED SAND with CLAY and GRAVEL
10.1
6.9
4.6
5.0
5.5
2.32
1.12
0.64
0.52
0.50
%CobblesD60
7.316
0.553
8.75
6.816
5.935
D100
100.00
4.82
26.84
31.18
28.90
%Clay%Sand%Gravel
49.1
2.3
51.1
48.0
44.6
40.8
90.8
44.3
47.1
49.9
0.0
0.0
0.0
0.0
0.0
D10
0.115
0.326
0.219
0.205
D30
1.115
0.266
1.353
0.882
0.781
37.5
12.5
37.5
25
25
%Fines %Silt
Boring ID
2.5 - 4
25 - 26.5
5 - 6.5
2.5 - 4
2.5 - 4
B-1
B-5
B-10
B-15
B-21
2.5 - 4
25 - 26.5
5 - 6.5
2.5 - 4
2.5 - 4
Depth (Ft)Boring ID
B-1
B-5
B-10
B-15
B-21
Depth (Ft)
11849 W Executive Dr Ste G
Boise, IDTerracon Project No. 62245017
N 2nd E and E Moody Road | Rexburg, Idaho
Rexburg Retail Development
USCS
GW-GC
SP-SM
GP
GP
SP-SC
0
5
10
15
20
25
30
35
40
45
50
55
60
65
70
75
80
85
90
95
100
0.0010.010.1110100
16 2044 100
U.S. Sieve Numbers
632 10 14 506 2001.5 83/4 1/23/8 30 403 601 140
HydrometerU.S. Sieve Opening in Inches
Grain Size Distribution
SandGravel
Grain Size (mm)
coarse fine coarse finemedium Silt or ClayCobbles
Pe
r
c
e
n
t
C
o
a
r
s
e
r
b
y
W
e
i
g
h
t
Pe
r
c
e
n
t
F
i
n
e
r
b
y
W
e
i
g
h
t
100
90
80
70
60
50
40
30
20
10
0
ASTM D422 / ASTM C136 / AASHTO T27
Facilities | Environmental | Geotechnical | Materials
LL PL PI Cc CuDescription
SANDY LEAN CLAY
POOLRY GRADED GRAVEL with CLAY and SAND
54.6
6.3
0.54
%CobblesD60
0.169
11.523
D100
47.92
%Clay%Sand%Gravel
9.4
53.0
36.0
40.7
0.0
0.0
D10
0.24
D30
1.223
25
37.5
%Fines %Silt
Boring ID
0 - 1.6
1.6 - 4
TP-24
TP-24
0 - 1.6
1.6 - 4
Depth (Ft)Boring ID
TP-24
TP-24
Depth (Ft)
11849 W Executive Dr Ste G
Boise, IDTerracon Project No. 62245017
N 2nd E and E Moody Road | Rexburg, Idaho
Rexburg Retail Development
USCS
CL
GP-GC
50
54
58
62
66
70
74
78
82
86
90
94
98
102
106
110
114
118
122
126
130
134
138
142
0 5 10 15 20 25 30 35 40 45
Curves of 100% Saturation
for Specific Gravity Equal to:
2.80
2.70
2.60
Moisture-Density Relationship
Dr
y
D
e
n
s
i
t
y
(
p
c
f
)
Water Content (%)
ASTM D698-Method B
Facilities | Environmental | Geotechnical | Materials
11849 W Executive Dr Ste G
Boise, IDTerracon Project No. 62245017
N 2nd E and E Moody Road | Rexburg, Idaho
Rexburg Retail Development
Description of Materials
Optimum Water Content
(%)
Maximum Dry Density
(pcf)Test Method
ASTM D698-Method B 106.5 17.06657 21 36
Fines
(%)PIPLLL
SANDY FAT CLAY(CH)
Fraction
>25 mm size
B-20 0.01 - 2.01
Depth (Ft)Boring ID
0.0
Supporting Information
Contents:
General Notes
Unified Soil Classification System
Note: All attachments are one page unless noted above.
Auger
Cuttings
Ring
Sampler
Standard
Penetration
Test
Facilities | Environmental | Geotechnical | Materials
less than 0.25
0.50 to 1.00
1.00 to 2.00
> 4.00
0.25 to 0.50
2.00 to 4.00
Unconfined
Compressive
Strength Qu (tsf)
Rexburg Retail Development
N 2nd E and E Moody Road | Rexburg, Idaho
Terracon Project No. 62245017
11849 W Executive Dr Ste G
Boise, ID
N
(HP)
(T)
(DCP)
UC
(PID)
(OVA)
Standard Penetration Test
Resistance (Blows/Ft.)
Hand Penetrometer
Torvane
Dynamic Cone Penetrometer
Unconfined Compressive
Strength
Photo-Ionization Detector
Organic Vapor Analyzer
Water Level After a
Specified Period of Time
Water Level After
a Specified Period of Time
Cave In
Encountered
Water Level Field Tests
Water Initially
Encountered
Sampling
Water levels indicated on the soil boring logs are the
levels measured in the borehole at the times indicated.
Groundwater level variations will occur over time. In
low permeability soils, accurate determination of
groundwater levels is not possible with short term
water level observations.
General Notes
Location And Elevation Notes
Exploration point locations as shown on the Exploration Plan and as noted on the soil boring logs in the form of Latitude and Longitude are
approximate. See Exploration and Testing Procedures in the report for the methods used to locate the exploration points for this project. Surface
elevation data annotated with +/- indicates that no actual topographical survey was conducted to confirm the surface elevation. Instead, the surface
elevation was approximately determined from topographic maps of the area.
Soil classification as noted on the soil boring logs is based Unified Soil Classification System. Where sufficient laboratory data exist to classify the soils
consistent with ASTM D2487 "Classification of Soils for Engineering Purposes" this procedure is used. ASTM D2488 "Description and Identification of
Soils (Visual-Manual Procedure)" is also used to classify the soils, particularly where insufficient laboratory data exist to classify the soils in accordance
with ASTM D2487. In addition to USCS classification, coarse grained soils are classified on the basis of their in-place relative density, and fine-grained
soils are classified on the basis of their consistency. See "Strength Terms" table below for details. The ASTM standards noted above are for reference
to methodology in general. In some cases, variations to methods are applied as a result of local practice or professional judgment.
Exploration/field results and/or laboratory test data contained within this document are intended for application to the project as described in this
document. Use of such exploration/field results and/or laboratory test data should not be used independently of this document.
Relevance of Exploration and Laboratory Test Results
Descriptive Soil Classification
Strength Terms
4 - 8
0 - 1
> 30
4 - 9
30 - 50
> 50
15 - 46
47 - 79
> 80 Very Stiff
Hard
< 3
3 - 5
11 - 18
19 - 36
2 - 4
8 - 15
15 - 30
(50% or more passing the No. 200 sieve.)
Consistency determined by laboratory shear strength testing, field visual-manual
procedures or standard penetration resistance
Relative Density of Coarse-Grained Soils
Very Loose
Loose
Medium Dense
Dense
Very Dense
10 - 29
0 - 3 0 - 5
6 - 14
Very Soft
Soft
Medium Stiff
Stiff
6 - 10
Consistency of Fine-Grained Soils
(More than 50% retained on No. 200 sieve.)
Density determined by Standard Penetration Resistance
Ring Sampler
(Blows/Ft.)Relative Density Consistency
Standard Penetration
or N-Value
(Blows/Ft.)
Standard Penetration
or N-Value
(Blows/Ft.)
Ring
Sampler
(Blows/Ft.)
> 37
_
Geotechnical Engineering Report
Rexburg Retail Development | Rexburg, Idaho
May 15, 2024 | Terracon Project No. 62245017
Facilities | Environmental | Geotechnical | Materials
Unified Soil Classification System
Criteria for Assigning Group Symbols and Group Names Using
Laboratory Tests A
Soil Classification
Group
Symbol Group Name B
Coarse-Grained Soils:
More than 50% retained
on No. 200 sieve
Gravels:
More than 50% of
coarse fraction
retained on No. 4
sieve
Clean Gravels:
Less than 5% fines C
Cu≥4 and 1≤Cc≤3 E GW Well-graded gravel F
Cu<4 and/or [Cc<1 or Cc>3.0] E GP Poorly graded gravel F
Gravels with Fines:
More than 12% fines C
Fines classify as ML or MH GM Silty gravel F, G, H
Fines classify as CL or CH GC Clayey gravel F, G, H
Sands:
50% or more of
coarse fraction
passes No. 4 sieve
Clean Sands:
Less than 5% fines D
Cu≥6 and 1≤Cc≤3 E SW Well-graded sand I
Cu<6 and/or [Cc<1 or Cc>3.0] E SP Poorly graded sand I
Sands with Fines:
More than 12% fines D
Fines classify as ML or MH SM Silty sand G, H, I
Fines classify as CL or CH SC Clayey sand G, H, I
Fine-Grained Soils:
50% or more passes the
No. 200 sieve
Silts and Clays:
Liquid limit less than
50
Inorganic: PI > 7 and plots above “A” line J CL Lean clay K, L, M
PI < 4 or plots below “A” line J ML Silt K, L, M
Organic: 𝐿𝐿𝐿𝐿 𝑜𝑜𝑜𝑜𝑜𝑜𝑜𝑜 𝑑𝑑𝑑𝑑𝑑𝑑𝑜𝑜𝑑𝑑𝐿𝐿𝐿𝐿 𝑜𝑜𝑜𝑜𝑛𝑛 𝑑𝑑𝑑𝑑𝑑𝑑𝑜𝑜𝑑𝑑< 0.75 OL Organic clay K, L, M, N
Organic silt K, L, M, O
Silts and Clays:
Liquid limit 50 or
more
Inorganic: PI plots on or above “A” line CH Fat clay K, L, M
PI plots below “A” line MH Elastic silt K, L, M
Organic: 𝐿𝐿𝐿𝐿 𝑜𝑜𝑜𝑜𝑜𝑜𝑜𝑜 𝑑𝑑𝑑𝑑𝑑𝑑𝑜𝑜𝑑𝑑𝐿𝐿𝐿𝐿 𝑜𝑜𝑜𝑜𝑛𝑛 𝑑𝑑𝑑𝑑𝑑𝑑𝑜𝑜𝑑𝑑< 0.75 OH Organic clay K, L, M, P
Organic silt K, L, M, Q
Highly organic soils: Primarily organic matter, dark in color, and organic odor PT Peat
A Based on the material passing the 3-inch (75-mm) sieve.
B If field sample contained cobbles or boulders, or both, add “with
cobbles or boulders, or both” to group name.
C Gravels with 5 to 12% fines require dual symbols: GW-GM well-
graded gravel with silt, GW-GC well-graded gravel with clay, GP-GM
poorly graded gravel with silt, GP-GC poorly graded gravel with clay.
D Sands with 5 to 12% fines require dual symbols: SW-SM well-
graded sand with silt, SW-SC well-graded sand with clay, SP-SM
poorly graded sand with silt, SP-SC poorly graded sand with clay.
E Cu = D60/D10 Cc =
F If soil contains ≥ 15% sand, add “with sand” to group name.
G If fines classify as CL-ML, use dual symbol GC-GM, or SC-SM.
H If fines are organic, add “with organic fines” to group name.
I If soil contains ≥ 15% gravel, add “with gravel” to group name.
J If Atterberg limits plot in shaded area, soil is a CL-ML, silty clay.
K If soil contains 15 to 29% plus No. 200, add “with sand” or
“with gravel,” whichever is predominant.
L If soil contains ≥ 30% plus No. 200 predominantly sand, add
“sandy” to group name.
M If soil contains ≥ 30% plus No. 200, predominantly gravel, add
“gravelly” to group name.
N PI ≥ 4 and plots on or above “A” line.
O PI < 4 or plots below “A” line.
P PI plots on or above “A” line.
Q PI plots below “A” line.
6010
2
30
DxD
)(D
11849 West Executive Drive, Suite G
Boise, Idaho 83713
P (208) 323-9520
Terracon.com
Facilities | Environmental | Geotechnical | Materials
Report Cover Letter to Sign May 23, 2024
WinCo Foods
650 N Armstrong Place
Boise, Idaho 83704
Attn: Ronald R. Schrieber, II, Project Manager, Store Development
P: (208) 859-1993
E: ronald.schrieber@wincofoods.com
Re: Addendum Letter to the Geotechnical Engineering Report
Rexburg Retail Development
Southeast corner of North 2nd East and East Moody Road
Rexburg, Idaho
Terracon Project No. 62245017
Dear Mr. Schrieber:
We have completed the scope of services for the above referenced project in general
accordance with Terracon Proposal No. P62245017 dated March 6, 2024. This addendum
letter presents the corrosivity results associated with Terracon’s previous Geotechnical
Report, Rexburg Retail Development dated May 15, 2024 (Terracon Project No.
62245017). The information presented in this letter is intended to be used in conjunction
with the referenced report.
Corrosivity
The table below lists the results of laboratory oxidation-reduction potential, soluble
sulfide content, soluble sulfate content, soluble chloride content, total salts, electrical
resistivity, and pH testing. The values may be used to estimate potential corrosive
characteristics of the on-site soils with respect to contact with the various underground
materials which will be used for project construction.
Results of soluble sulfate testing indicate samples of the on-site soils tested processes
negligible sulfate concentrations when classified in accordance with Table 19.3.1.1 2019
ACI Design Manual. Concrete should be designed in accordance with the provisions of
the ACI Design Manual, Section 318, Chapter 19.
750 Pilot Road, Suite F
Las Vegas, Nevada 89119
(702) 597-9393
Client
Date Received:Lab No.: 24-0195
Analyzed By:
The tests were performed in general accordance with applicable ASTM and AWWA test methods. This report is exclusively for the use of
the client indicated above and shall not be reproduced except in full without the written consent of our company. Test results transmitted
herein are only applicable to the actual samples tested at the location(s) referenced and are not necessarily indicative of the properties of
other apparently similar or identical materials.
Laboratory Coordinator
Nathan Campo
pH Analysis, ASTM D4972
Water Soluble Sulfate (SO4), ASTM D516
(mg/kg)
Sulfides, AWWA 4500-S D, (mg/Kg)
Chlorides, ASTM D512, (mg/kg)
Red-Ox, ASTM G200, (mV)
Total Salts, AWWA 2520 B, (mg/Kg)
Saturated Minimum Resistivity, ASTM G-57,
(ohm-cm)
46
Nil
127
+728
430
Sample Depth (ft.) 0.0
Project
Rexburg Retail Development
5/9/2024
Results of Corrosion Analysis
Sample Number
Sample Location
Terracon (62)Sample Submitted By:
350
5674
--
B-1
--
B-23
0.0-1.8
6.73
3686
7.41
101
Nil
145
+732
United States
Department of
Agriculture
A product of the National
Cooperative Soil Survey,
a joint effort of the United
States Department of
Agriculture and other
Federal agencies, State
agencies including the
Agricultural Experiment
Stations, and local
participants
Custom Soil Resource
Report for
Madison County
Area, Idaho
Rexburg WinCo Foods
Natural
Resources
Conservation
Service
November 12, 2024
Preface
Soil surveys contain information that affects land use planning in survey areas.
They highlight soil limitations that affect various land uses and provide information
about the properties of the soils in the survey areas. Soil surveys are designed for
many different users, including farmers, ranchers, foresters, agronomists, urban
planners, community officials, engineers, developers, builders, and home buyers.
Also, conservationists, teachers, students, and specialists in recreation, waste
disposal, and pollution control can use the surveys to help them understand,
protect, or enhance the environment.
Various land use regulations of Federal, State, and local governments may impose
special restrictions on land use or land treatment. Soil surveys identify soil
properties that are used in making various land use or land treatment decisions.
The information is intended to help the land users identify and reduce the effects of
soil limitations on various land uses. The landowner or user is responsible for
identifying and complying with existing laws and regulations.
Although soil survey information can be used for general farm, local, and wider area
planning, onsite investigation is needed to supplement this information in some
cases. Examples include soil quality assessments (http://www.nrcs.usda.gov/wps/
portal/nrcs/main/soils/health/) and certain conservation and engineering
applications. For more detailed information, contact your local USDA Service Center
(https://offices.sc.egov.usda.gov/locator/app?agency=nrcs) or your NRCS State Soil
Scientist (http://www.nrcs.usda.gov/wps/portal/nrcs/detail/soils/contactus/?
cid=nrcs142p2_053951).
Great differences in soil properties can occur within short distances. Some soils are
seasonally wet or subject to flooding. Some are too unstable to be used as a
foundation for buildings or roads. Clayey or wet soils are poorly suited to use as
septic tank absorption fields. A high water table makes a soil poorly suited to
basements or underground installations.
The National Cooperative Soil Survey is a joint effort of the United States
Department of Agriculture and other Federal agencies, State agencies including the
Agricultural Experiment Stations, and local agencies. The Natural Resources
Conservation Service (NRCS) has leadership for the Federal part of the National
Cooperative Soil Survey.
Information about soils is updated periodically. Updated information is available
through the NRCS Web Soil Survey, the site for official soil survey information.
The U.S. Department of Agriculture (USDA) prohibits discrimination in all its
programs and activities on the basis of race, color, national origin, age, disability,
and where applicable, sex, marital status, familial status, parental status, religion,
sexual orientation, genetic information, political beliefs, reprisal, or because all or a
part of an individual's income is derived from any public assistance program. (Not
all prohibited bases apply to all programs.) Persons with disabilities who require
2
alternative means for communication of program information (Braille, large print,
audiotape, etc.) should contact USDA's TARGET Center at (202) 720-2600 (voice
and TDD). To file a complaint of discrimination, write to USDA, Director, Office of
Civil Rights, 1400 Independence Avenue, S.W., Washington, D.C. 20250-9410 or
call (800) 795-3272 (voice) or (202) 720-6382 (TDD). USDA is an equal opportunity
provider and employer.
3
Contents
Preface....................................................................................................................2
How Soil Surveys Are Made..................................................................................5
Soil Map..................................................................................................................8
Soil Map................................................................................................................9
Legend................................................................................................................10
Map Unit Legend................................................................................................11
Map Unit Descriptions.........................................................................................11
Madison County Area, Idaho..........................................................................13
1—Annis silty clay loam..............................................................................13
64—Withers silty clay loam.........................................................................14
References............................................................................................................16
4
How Soil Surveys Are Made
Soil surveys are made to provide information about the soils and miscellaneous
areas in a specific area. They include a description of the soils and miscellaneous
areas and their location on the landscape and tables that show soil properties and
limitations affecting various uses. Soil scientists observed the steepness, length,
and shape of the slopes; the general pattern of drainage; the kinds of crops and
native plants; and the kinds of bedrock. They observed and described many soil
profiles. A soil profile is the sequence of natural layers, or horizons, in a soil. The
profile extends from the surface down into the unconsolidated material in which the
soil formed or from the surface down to bedrock. The unconsolidated material is
devoid of roots and other living organisms and has not been changed by other
biological activity.
Currently, soils are mapped according to the boundaries of major land resource
areas (MLRAs). MLRAs are geographically associated land resource units that
share common characteristics related to physiography, geology, climate, water
resources, soils, biological resources, and land uses (USDA, 2006). Soil survey
areas typically consist of parts of one or more MLRA.
The soils and miscellaneous areas in a survey area occur in an orderly pattern that
is related to the geology, landforms, relief, climate, and natural vegetation of the
area. Each kind of soil and miscellaneous area is associated with a particular kind
of landform or with a segment of the landform. By observing the soils and
miscellaneous areas in the survey area and relating their position to specific
segments of the landform, a soil scientist develops a concept, or model, of how they
were formed. Thus, during mapping, this model enables the soil scientist to predict
with a considerable degree of accuracy the kind of soil or miscellaneous area at a
specific location on the landscape.
Commonly, individual soils on the landscape merge into one another as their
characteristics gradually change. To construct an accurate soil map, however, soil
scientists must determine the boundaries between the soils. They can observe only
a limited number of soil profiles. Nevertheless, these observations, supplemented
by an understanding of the soil-vegetation-landscape relationship, are sufficient to
verify predictions of the kinds of soil in an area and to determine the boundaries.
Soil scientists recorded the characteristics of the soil profiles that they studied. They
noted soil color, texture, size and shape of soil aggregates, kind and amount of rock
fragments, distribution of plant roots, reaction, and other features that enable them
to identify soils. After describing the soils in the survey area and determining their
properties, the soil scientists assigned the soils to taxonomic classes (units).
Taxonomic classes are concepts. Each taxonomic class has a set of soil
characteristics with precisely defined limits. The classes are used as a basis for
comparison to classify soils systematically. Soil taxonomy, the system of taxonomic
classification used in the United States, is based mainly on the kind and character
of soil properties and the arrangement of horizons within the profile. After the soil
5
scientists classified and named the soils in the survey area, they compared the
individual soils with similar soils in the same taxonomic class in other areas so that
they could confirm data and assemble additional data based on experience and
research.
The objective of soil mapping is not to delineate pure map unit components; the
objective is to separate the landscape into landforms or landform segments that
have similar use and management requirements. Each map unit is defined by a
unique combination of soil components and/or miscellaneous areas in predictable
proportions. Some components may be highly contrasting to the other components
of the map unit. The presence of minor components in a map unit in no way
diminishes the usefulness or accuracy of the data. The delineation of such
landforms and landform segments on the map provides sufficient information for the
development of resource plans. If intensive use of small areas is planned, onsite
investigation is needed to define and locate the soils and miscellaneous areas.
Soil scientists make many field observations in the process of producing a soil map.
The frequency of observation is dependent upon several factors, including scale of
mapping, intensity of mapping, design of map units, complexity of the landscape,
and experience of the soil scientist. Observations are made to test and refine the
soil-landscape model and predictions and to verify the classification of the soils at
specific locations. Once the soil-landscape model is refined, a significantly smaller
number of measurements of individual soil properties are made and recorded.
These measurements may include field measurements, such as those for color,
depth to bedrock, and texture, and laboratory measurements, such as those for
content of sand, silt, clay, salt, and other components. Properties of each soil
typically vary from one point to another across the landscape.
Observations for map unit components are aggregated to develop ranges of
characteristics for the components. The aggregated values are presented. Direct
measurements do not exist for every property presented for every map unit
component. Values for some properties are estimated from combinations of other
properties.
While a soil survey is in progress, samples of some of the soils in the area generally
are collected for laboratory analyses and for engineering tests. Soil scientists
interpret the data from these analyses and tests as well as the field-observed
characteristics and the soil properties to determine the expected behavior of the
soils under different uses. Interpretations for all of the soils are field tested through
observation of the soils in different uses and under different levels of management.
Some interpretations are modified to fit local conditions, and some new
interpretations are developed to meet local needs. Data are assembled from other
sources, such as research information, production records, and field experience of
specialists. For example, data on crop yields under defined levels of management
are assembled from farm records and from field or plot experiments on the same
kinds of soil.
Predictions about soil behavior are based not only on soil properties but also on
such variables as climate and biological activity. Soil conditions are predictable over
long periods of time, but they are not predictable from year to year. For example,
soil scientists can predict with a fairly high degree of accuracy that a given soil will
have a high water table within certain depths in most years, but they cannot predict
that a high water table will always be at a specific level in the soil on a specific date.
After soil scientists located and identified the significant natural bodies of soil in the
survey area, they drew the boundaries of these bodies on aerial photographs and
Custom Soil Resource Report
6
identified each as a specific map unit. Aerial photographs show trees, buildings,
fields, roads, and rivers, all of which help in locating boundaries accurately.
Custom Soil Resource Report
7
Soil Map
The soil map section includes the soil map for the defined area of interest, a list of
soil map units on the map and extent of each map unit, and cartographic symbols
displayed on the map. Also presented are various metadata about data used to
produce the map, and a description of each soil map unit.
8
9
Custom Soil Resource Report
Soil Map
48
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437440 437520 437600 437680 437760 437840 437920 438000 438080 438160 438240
437440 437520 437600 437680 437760 437840 437920 438000 438080 438160 438240
43° 51' 22'' N
11
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43° 51' 22'' N
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43° 51' 5'' N
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43° 51' 5'' N
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N
Map projection: Web Mercator Corner coordinates: WGS84 Edge tics: UTM Zone 12N WGS84
0 150 300 600 900Feet
0 50 100 200 300Meters
Map Scale: 1:3,730 if printed on A landscape (11" x 8.5") sheet.
Soil Map may not be valid at this scale.
MAP LEGEND MAP INFORMATION
Area of Interest (AOI)
Area of Interest (AOI)
Soils
Soil Map Unit Polygons
Soil Map Unit Lines
Soil Map Unit Points
Special Point Features
Blowout
Borrow Pit
Clay Spot
Closed Depression
Gravel Pit
Gravelly Spot
Landfill
Lava Flow
Marsh or swamp
Mine or Quarry
Miscellaneous Water
Perennial Water
Rock Outcrop
Saline Spot
Sandy Spot
Severely Eroded Spot
Sinkhole
Slide or Slip
Sodic Spot
Spoil Area
Stony Spot
Very Stony Spot
Wet Spot
Other
Special Line Features
Water Features
Streams and Canals
Transportation
Rails
Interstate Highways
US Routes
Major Roads
Local Roads
Background
Aerial Photography
The soil surveys that comprise your AOI were mapped at
1:24,000.
Warning: Soil Map may not be valid at this scale.
Enlargement of maps beyond the scale of mapping can cause
misunderstanding of the detail of mapping and accuracy of soil
line placement. The maps do not show the small areas of
contrasting soils that could have been shown at a more detailed
scale.
Please rely on the bar scale on each map sheet for map
measurements.
Source of Map: Natural Resources Conservation Service
Web Soil Survey URL:
Coordinate System: Web Mercator (EPSG:3857)
Maps from the Web Soil Survey are based on the Web Mercator
projection, which preserves direction and shape but distorts
distance and area. A projection that preserves area, such as the
Albers equal-area conic projection, should be used if more
accurate calculations of distance or area are required.
This product is generated from the USDA-NRCS certified data as
of the version date(s) listed below.
Soil Survey Area: Madison County Area, Idaho
Survey Area Data: Version 19, Aug 22, 2024
Soil map units are labeled (as space allows) for map scales
1:50,000 or larger.
Date(s) aerial images were photographed: Jul 20, 2022—Jul 25,
2022
The orthophoto or other base map on which the soil lines were
compiled and digitized probably differs from the background
imagery displayed on these maps. As a result, some minor
shifting of map unit boundaries may be evident.
Custom Soil Resource Report
10
Map Unit Legend
Map Unit Symbol Map Unit Name Acres in AOI Percent of AOI
1 Annis silty clay loam 4.4 15.8%
64 Withers silty clay loam 23.3 84.2%
Totals for Area of Interest 27.6 100.0%
Map Unit Descriptions
The map units delineated on the detailed soil maps in a soil survey represent the
soils or miscellaneous areas in the survey area. The map unit descriptions, along
with the maps, can be used to determine the composition and properties of a unit.
A map unit delineation on a soil map represents an area dominated by one or more
major kinds of soil or miscellaneous areas. A map unit is identified and named
according to the taxonomic classification of the dominant soils. Within a taxonomic
class there are precisely defined limits for the properties of the soils. On the
landscape, however, the soils are natural phenomena, and they have the
characteristic variability of all natural phenomena. Thus, the range of some
observed properties may extend beyond the limits defined for a taxonomic class.
Areas of soils of a single taxonomic class rarely, if ever, can be mapped without
including areas of other taxonomic classes. Consequently, every map unit is made
up of the soils or miscellaneous areas for which it is named and some minor
components that belong to taxonomic classes other than those of the major soils.
Most minor soils have properties similar to those of the dominant soil or soils in the
map unit, and thus they do not affect use and management. These are called
noncontrasting, or similar, components. They may or may not be mentioned in a
particular map unit description. Other minor components, however, have properties
and behavioral characteristics divergent enough to affect use or to require different
management. These are called contrasting, or dissimilar, components. They
generally are in small areas and could not be mapped separately because of the
scale used. Some small areas of strongly contrasting soils or miscellaneous areas
are identified by a special symbol on the maps. If included in the database for a
given area, the contrasting minor components are identified in the map unit
descriptions along with some characteristics of each. A few areas of minor
components may not have been observed, and consequently they are not
mentioned in the descriptions, especially where the pattern was so complex that it
was impractical to make enough observations to identify all the soils and
miscellaneous areas on the landscape.
The presence of minor components in a map unit in no way diminishes the
usefulness or accuracy of the data. The objective of mapping is not to delineate
pure taxonomic classes but rather to separate the landscape into landforms or
landform segments that have similar use and management requirements. The
delineation of such segments on the map provides sufficient information for the
development of resource plans. If intensive use of small areas is planned, however,
Custom Soil Resource Report
11
onsite investigation is needed to define and locate the soils and miscellaneous
areas.
An identifying symbol precedes the map unit name in the map unit descriptions.
Each description includes general facts about the unit and gives important soil
properties and qualities.
Soils that have profiles that are almost alike make up a soil series. Except for
differences in texture of the surface layer, all the soils of a series have major
horizons that are similar in composition, thickness, and arrangement.
Soils of one series can differ in texture of the surface layer, slope, stoniness,
salinity, degree of erosion, and other characteristics that affect their use. On the
basis of such differences, a soil series is divided into soil phases. Most of the areas
shown on the detailed soil maps are phases of soil series. The name of a soil phase
commonly indicates a feature that affects use or management. For example, Alpha
silt loam, 0 to 2 percent slopes, is a phase of the Alpha series.
Some map units are made up of two or more major soils or miscellaneous areas.
These map units are complexes, associations, or undifferentiated groups.
A complex consists of two or more soils or miscellaneous areas in such an intricate
pattern or in such small areas that they cannot be shown separately on the maps.
The pattern and proportion of the soils or miscellaneous areas are somewhat similar
in all areas. Alpha-Beta complex, 0 to 6 percent slopes, is an example.
An association is made up of two or more geographically associated soils or
miscellaneous areas that are shown as one unit on the maps. Because of present
or anticipated uses of the map units in the survey area, it was not considered
practical or necessary to map the soils or miscellaneous areas separately. The
pattern and relative proportion of the soils or miscellaneous areas are somewhat
similar. Alpha-Beta association, 0 to 2 percent slopes, is an example.
An undifferentiated group is made up of two or more soils or miscellaneous areas
that could be mapped individually but are mapped as one unit because similar
interpretations can be made for use and management. The pattern and proportion
of the soils or miscellaneous areas in a mapped area are not uniform. An area can
be made up of only one of the major soils or miscellaneous areas, or it can be made
up of all of them. Alpha and Beta soils, 0 to 2 percent slopes, is an example.
Some surveys include miscellaneous areas. Such areas have little or no soil
material and support little or no vegetation. Rock outcrop is an example.
Custom Soil Resource Report
12
Madison County Area, Idaho
1—Annis silty clay loam
Map Unit Setting
National map unit symbol: 2tc2
Elevation: 4,800 feet
Mean annual precipitation: 8 to 13 inches
Mean annual air temperature: 43 to 46 degrees F
Frost-free period: 100 to 115 days
Farmland classification: Prime farmland if irrigated
Map Unit Composition
Annis and similar soils:85 percent
Estimates are based on observations, descriptions, and transects of the mapunit.
Description of Annis
Setting
Landform:Terraces
Down-slope shape:Linear
Across-slope shape:Linear
Parent material:Mixed alluvium
Typical profile
Ap - 0 to 7 inches: silty clay loam
Bw - 7 to 21 inches: silt loam
Bk1 - 21 to 49 inches: silty clay loam
Bk2 - 49 to 60 inches: silt loam
Properties and qualities
Slope:0 to 1 percent
Depth to restrictive feature:More than 80 inches
Drainage class:Moderately well drained
Capacity of the most limiting layer to transmit water (Ksat):Moderately high (0.20
to 0.60 in/hr)
Depth to water table:About 36 to 60 inches
Frequency of flooding:None
Frequency of ponding:None
Calcium carbonate, maximum content:35 percent
Maximum salinity:Nonsaline to very slightly saline (0.0 to 2.0 mmhos/cm)
Sodium adsorption ratio, maximum:10.0
Available water supply, 0 to 60 inches: High (about 12.0 inches)
Interpretive groups
Land capability classification (irrigated): 3e
Land capability classification (nonirrigated): 6c
Hydrologic Soil Group: C
Ecological site: R011XB031ID - Silty 7-10 PZ KRLA2/ACHY
Hydric soil rating: No
Custom Soil Resource Report
13
64—Withers silty clay loam
Map Unit Setting
National map unit symbol: 2tf0
Elevation: 4,500 to 5,500 feet
Mean annual precipitation: 8 to 12 inches
Mean annual air temperature: 39 to 45 degrees F
Frost-free period: 100 to 110 days
Farmland classification: Prime farmland if irrigated
Map Unit Composition
Withers and similar soils:85 percent
Estimates are based on observations, descriptions, and transects of the mapunit.
Description of Withers
Setting
Landform:Flood plains, terraces
Down-slope shape:Linear
Across-slope shape:Linear
Parent material:Mixed alluvium
Typical profile
A - 0 to 7 inches: silty clay loam
Bw - 7 to 16 inches: silty clay loam
Bt - 16 to 26 inches: silty clay loam
2C1 - 26 to 36 inches: very gravelly loamy sand
3C2 - 36 to 60 inches: stratified sand to gravel
Properties and qualities
Slope:0 to 1 percent
Depth to restrictive feature:More than 80 inches
Drainage class:Somewhat poorly drained
Capacity of the most limiting layer to transmit water (Ksat):Moderately high (0.20
to 0.60 in/hr)
Depth to water table:About 24 to 48 inches
Frequency of flooding:None
Frequency of ponding:None
Calcium carbonate, maximum content:10 percent
Maximum salinity:Nonsaline to very slightly saline (0.0 to 2.0 mmhos/cm)
Sodium adsorption ratio, maximum:5.0
Available water supply, 0 to 60 inches: Low (about 5.9 inches)
Interpretive groups
Land capability classification (irrigated): 3e
Land capability classification (nonirrigated): 6c
Hydrologic Soil Group: C
Ecological site: R011XY019ID - Meadow DECA18-CANE2
Hydric soil rating: No
Custom Soil Resource Report
14
Custom Soil Resource Report
15
References
American Association of State Highway and Transportation Officials (AASHTO).
2004. Standard specifications for transportation materials and methods of sampling
and testing. 24th edition.
American Society for Testing and Materials (ASTM). 2005. Standard classification of
soils for engineering purposes. ASTM Standard D2487-00.
Cowardin, L.M., V. Carter, F.C. Golet, and E.T. LaRoe. 1979. Classification of
wetlands and deep-water habitats of the United States. U.S. Fish and Wildlife
Service FWS/OBS-79/31.
Federal Register. July 13, 1994. Changes in hydric soils of the United States.
Federal Register. September 18, 2002. Hydric soils of the United States.
Hurt, G.W., and L.M. Vasilas, editors. Version 6.0, 2006. Field indicators of hydric
soils in the United States.
National Research Council. 1995. Wetlands: Characteristics and boundaries.
Soil Survey Division Staff. 1993. Soil survey manual. Soil Conservation Service.
U.S. Department of Agriculture Handbook 18. http://www.nrcs.usda.gov/wps/portal/
nrcs/detail/national/soils/?cid=nrcs142p2_054262
Soil Survey Staff. 1999. Soil taxonomy: A basic system of soil classification for
making and interpreting soil surveys. 2nd edition. Natural Resources Conservation
Service, U.S. Department of Agriculture Handbook 436. http://
www.nrcs.usda.gov/wps/portal/nrcs/detail/national/soils/?cid=nrcs142p2_053577
Soil Survey Staff. 2010. Keys to soil taxonomy. 11th edition. U.S. Department of
Agriculture, Natural Resources Conservation Service. http://
www.nrcs.usda.gov/wps/portal/nrcs/detail/national/soils/?cid=nrcs142p2_053580
Tiner, R.W., Jr. 1985. Wetlands of Delaware. U.S. Fish and Wildlife Service and
Delaware Department of Natural Resources and Environmental Control, Wetlands
Section.
United States Army Corps of Engineers, Environmental Laboratory. 1987. Corps of
Engineers wetlands delineation manual. Waterways Experiment Station Technical
Report Y-87-1.
United States Department of Agriculture, Natural Resources Conservation Service.
National forestry manual. http://www.nrcs.usda.gov/wps/portal/nrcs/detail/soils/
home/?cid=nrcs142p2_053374
United States Department of Agriculture, Natural Resources Conservation Service.
National range and pasture handbook. http://www.nrcs.usda.gov/wps/portal/nrcs/
detail/national/landuse/rangepasture/?cid=stelprdb1043084
16
United States Department of Agriculture, Natural Resources Conservation Service.
National soil survey handbook, title 430-VI. http://www.nrcs.usda.gov/wps/portal/
nrcs/detail/soils/scientists/?cid=nrcs142p2_054242
United States Department of Agriculture, Natural Resources Conservation Service.
2006. Land resource regions and major land resource areas of the United States,
the Caribbean, and the Pacific Basin. U.S. Department of Agriculture Handbook
296. http://www.nrcs.usda.gov/wps/portal/nrcs/detail/national/soils/?
cid=nrcs142p2_053624
United States Department of Agriculture, Soil Conservation Service. 1961. Land
capability classification. U.S. Department of Agriculture Handbook 210. http://
www.nrcs.usda.gov/Internet/FSE_DOCUMENTS/nrcs142p2_052290.pdf
Custom Soil Resource Report
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