HomeMy WebLinkAbout20_GeotechnicalReportForReference_04132021MONTANA | WASHINGTON | IDAHO | NORTH DAKOTA | PENNSYLVANIA
JOB NO. B20-068-002 October 2020
REPORT OF GEOTECHNICAL ASSESSMENT
CLIENT ENGINEER
HomeBase Partners
20 North Tracy Avenue
Bozeman, MT 59715
Craig Nadeau, PE
Craig.nadeau@tdhengineering.com
REPORT OF GEOTECHNICAL INVESTIGATION
PROJECT NAME
PROJECT LOCATION 406.586.0277
tdhengineering.com
234 E. Babcock, Suite 3
Bozeman, MT 59715
NORTH CENTRAL DEVELOPMENT
BOZEMAN, MONTANA
North Central Development Table of Contents
Bozeman, Montana i
Table of Contents
1.0 EXECUTIVE SUMMARY ......................................................................................................... 1
2.0 INTRODUCTION ..................................................................................................................... 3
2.1 Purpose and Scope .......................................................................................................... 3
2.2 Project Description ........................................................................................................... 3
3.0 SITE CONDITIONS ................................................................................................................. 5
3.1 Geology and Physiography .............................................................................................. 5
3.2 Surface Conditions ........................................................................................................... 5
3.3 Preliminary Subsurface Conditions .................................................................................. 6
3.3.1 Soils ........................................................................................................................... 6
3.3.2 Ground Water ........................................................................................................... 8
4.0 ENGINEERING ANALYSIS .................................................................................................. 13
4.1 Site Grading and Excavations........................................................................................ 13
4.2 Foundation Systems ...................................................................................................... 13
4.2.1 Block 4 .................................................................................................................... 14
4.2.2 Block 3 .................................................................................................................... 14
4.2.3 Mountain View ........................................................................................................ 15
4.2.4 Summary ................................................................................................................. 16
4.3 Slab-on-Grade Construction .......................................................................................... 16
4.4 Pavement Systems ........................................................................................................ 17
5.0 RECOMMENDATIONS ......................................................................................................... 19
5.1 Site Grading and Excavations........................................................................................ 19
5.2 Conventional Shallow Foundations on Structural Fill .................................................... 20
5.3 Conventional Shallow Foundations Over EAP Improved Soils ..................................... 21
5.4 Foundation Walls............................................................................................................ 22
5.5 Exterior Concrete Flatwork ............................................................................................ 23
5.6 Interior Concrete Floor Slabs ......................................................................................... 23
5.7 Pavements ..................................................................................................................... 24
5.8 Continuing Services ....................................................................................................... 26
6.0 SUMMARY OF PRELIMINARY FIELD AND LABORATORY STUDIES ............................. 28
6.1 Field Explorations ........................................................................................................... 28
6.2 Laboratory Testing ......................................................................................................... 28
7.0 LIMITATIONS ........................................................................................................................ 30
North Central Development Executive Summary
Bozeman, Montana Page ii
APPENDIX
Boring Location Map (Figure 1)
Logs of Exploratory Borings (Figures 2 through 15)
Laboratory Test Data (Figures 16 through 54)
LTTPBind Online PG Asphalt Binder Analysis Summary
Construction Standard 02801-06C
Soil Classification and Sampling Terminology for Engineering Purposes
Classification of Soils for Engineering Purposes
North Central Development Executive Summary
Bozeman, Montana Page 1
GEOTECHNICAL REPORT
NORTH CENTRAL DEVELOPMENT
BOZEMAN, MONTANA
1.0 EXECUTIVE SUMMARY
The geotechnical investigation for the proposed North Central development encountered primarily
fine-grained sandy lean clay overlying dense native clayey gravel with sand. A single boring
encountered surficial fill material, presumably associated with the original site grading and
construction of the existing Medical Arts facility. The overall North Central development is divided
into three separate areas, each proposed to encompass all or part of a city block. The first section,
referred to as “Block 4”, is located on the west side of North Willson Avenue between Beall and
Villard Streets and currently consists of asphalt paved parking lot utilized by the Medical Arts
building. The second section, referred to as “Block 3”, is located between North Willson and North
Tracy Avenues and between Beall and Villard Streets. Block 3 is currently the site of the existing
Medical Arts building which is planned to be demolished in the future and prior to construction of
this project. The final portion of the project referred to as “Mountain View,” is located to the south of
Block 3 between Beall and Lamme Streets and between North Willson and North Tracy Avenues.
This area currently contains the old Mountain View Care Center facility, which is no longer in
operation. The existing buildings in this section will be demolished except for the westernmost
structure.
The seismic site class for the area is D, and the risk of seismically-induced liquefaction or soil
settlement is considered low and does not warrant additional evaluation. The primary geotechnical
concerns regarding this project are the presence of soft compressible surficial fine-grained soils,
existing basements which will be demolished and backfilled, the potential for unknown fill material,
and potentially shallow ground water conditions. In general, the soft, fine-grained soils are not
suitable to support loads typical of multi-story construction without experiencing excessive
settlement and adverse foundation performance. Differential settlements would be exacerbated by
the need to demolish and backfill existing basements beneath portions of the existing construction
with readily available structural gravel. These materials can act very differently than native soils
when loaded, which leads to differential settlement. Furthermore, the project area is highly
developed, which increases the potential for encountering fill materials, which often contain
construction debris and may not be suitable for use beneath the new construction. Fill was
encountered in one boring performed during our investigation and is anticipated to be present at
other locations, which could not be investigated due to access restrictions. Based on our
understanding of the project and the concerns discussed above, it is our opinion that all new
building foundations and slab systems will require subsurface improvements comprised of either:
• The complete removal of the fine-grained surficial soils down to native gravels and
replacement with properly compacted structural fill.
North Central Development Executive Summary
Bozeman, Montana Page 2
• The use of a specialized subsurface improvement system using Engineered Aggregate
Piers (EAP) to improve to soft clay soils in place and facilitate standard foundation
construction over these materials.
• Other deep foundation methods used to bridge structural loads to competent bearing
material.
All of these methods are suitable to achieve design bearing pressures of at least 4,000 pounds
per square foot (psf) and should limit potential foundation and slab settlements to less than ¾-
inch; however, other deep foundation methods are not commonly utilized in the Bozeman area
and typically are not cost-effective thus we have not considered them as part of this report.
We have also included recommendations for exterior concrete flatwork and asphalt pavement
system for your consideration, which consider the presence of the soft, fine-grained soils. In
most cases, it is not practical or cost-effective to completely remove or improve these soft soils
beneath exterior site development features. Also, these features are generally able to tolerate a
higher level of potential movement without experiencing detrimental impact to their function on
the site. However, if the project is unable or unwilling to accept any risk of potential vertical
movements or distress to such exterior features, the use of similar improvement methods, as
discussed above, should be incorporated throughout the project site.
North Central Development Introduction
Bozeman, Montana Page 3
2.0 INTRODUCTION
2.1 Purpose and Scope
This report presents our assessment of the proposed North Central Development planned for
downtown Bozeman, Montana. This assessment has been prepared based on geotechnical
investigations conducted in May 2019 and September 2020 across the limits of the planned
development. The purpose of this assessment is to provide geotechnical recommendations for
the support of the proposed structures and design of the overall project.
A preliminary geotechnical investigation comprised of four borings with completed ground water
monitoring wells was performed in May 2019 within the limits of this development. Samples
were obtained from these borings and tested in our Great Falls laboratory to verify field
classifications. Results of our preliminary investigation were considered and used in this
analysis and report.
2.2 Project Description
The overall North Central Development is divided into three separate areas and each is
proposed to encompass all or part of a city block. The first section, referred to as “Block 4”, is
located on the west side of North Willson Avenue between Beall and Villard Streets. The area
currently consists of an asphalt paved parking lot utilized by visitors to the adjacent Medical Arts
building. We understand that this site is anticipated for a future structure being approximately
30,000 square feet is plan. This structure is anticipated to be six-stories above grade with the
northern three quarters incorporating a below-grade basement extending approximately 10 feet
below finished exterior grade. The lower 2.5 stories will be concrete parking structure with four
stories of wood framing above.
The second section of the project is referred to as “Block 3” and is located between North
Willson and North Tracy Avenues and also between Beall and Villard Streets. This area is the
current location of the Medical Arts facility and associated asphalt parking lots. The future
development will include the demolition and removal of the existing infrastructure. It will be
replaced with five separate structures ranging in size from approximately 6,000 to 15,000
square feet in plan and as summarized below.
• Building 3-5 and 3-4 are both to be six-stories above grade with a basement for
parking. They will utilize two post-tensioned decks at the lower levels with five floors
of wood-framing above.
• Building 3-3 is also to be a six-story structure but will not include any below-grade
space. It will utilize a single post-tensioned deck at the lower level with five floors of
wood-framing above.
North Central Development Introduction
Bozeman, Montana Page 4
• Buildings 3-2 and 3-1 are both to be five-stories above grade with no below-grade
space. They will utilize a single post-tensioned deck at the lower level with four
floors of wood-framing above.
The final section of the project referred to as “Mountain View”, is located to the south of Block 3.
It comprises the eastern three-quarters of the block between Beall and Lamme Streets and
North Willson and Tracy Avenues. This is the current location of the now-closed Mountain View
Care Center facility. Like the Medical Arts building, the existing Rocky Mountain Care Center is
to be demolished. Two new structures are planned to be built on this portion of the project and
will range in size from approximately 10,000 and 20,000 square feet in plan, respectively. Both
are to include five-stories above grade with no below-grade basement planned. They will be
completely constructed of post-tensioned concrete or steel.
The overall development area is also anticipated to consist of portions of asphalt pavement,
primarily for access roads between structures in Block 3. Typical landscaping and exterior
concrete flatwork are also expected.
Below grade storm water retention and infiltration are also common on these projects and are
anticipated.
North Central Development Site Conditions
Bozeman, Montana Page 5
3.0 SITE CONDITIONS
3.1 Geology and Physiography
The downtown Bozeman area is geologically characterized as gravel (Qgr, QTgr) and upper
Tertiary sediment or sedimentary rock (Tsu). The gravel formations are comprised of variable
deposits that range from pebble to boulder size and include sand, silt, and clay. The deposits
are dominantly alluvial terrace, abandoned channel and flood plain, remnant alluvial fan, and
local glacial outwash. Upper Tertiary sediments also frequent the area but are generally less
common. These sediments and sedimentary rock formations consist of conglomerate,
tuffaceous sandstone and siltstone, marlstone, and sediment or ash beds.
Figure 1
Geologic Map of Montana, Edition 1.0 (2007)
Montana Bureau of Mines & Geology
Based on the subsurface conditions encountered, the site falls under seismic Site Class D. The
structural engineer should utilize the site classification above to determine the appropriate
seismic design data for use on this project in accordance with current applicable building codes.
The likelihood of seismically-induced soil liquefaction or settlement for this project is low and
does not warrant additional evaluation.
3.2 Surface Conditions
The existing area for this development is heavily developed, with existing parking lots and
structures covering the planned development areas. Block 4, located west of North Willson
Avenue between Beall and Villard Streets, is currently utilized as an asphalt parking lot for the
adjacent Medical Arts complex located in Block 3. The parking lot is slightly elevated above the
North Central Development Site Conditions
Bozeman, Montana Page 6
elevation of North Willson Avenue, and the east side is supported by a small (approximately
two-foot-high) retaining wall with irrigated sod and concrete sidewalks in the boulevards.
Block 3 currently consists of an approximately 50,000-square-foot building housing the
Bozeman Medical Arts Center. The structure is mainly single-story with a three-story section on
the north end. All or part of this structure is known to include a full-depth basement. Existing
asphalt parking lots are located on the northwest and northeast sides of the existing building,
with the southwest, south, and southeast sides comprised of irrigated sod and landscaping.
Several concrete sidewalks and similar features surround the existing facility.
The Mountain View block is heavily developed like Block 3 and currently consists of an
approximate 23,000-square-foot structure previously housing the Mountain View Care Center.
The structure is predominantly two to three stories and constructed of brick and concrete.
Based on exterior observations, the structure may include some below-grade space (partial
height basement). The structure is predominantly surrounded by irrigated sod, landscaping,
exterior concrete flatwork, and limited asphalt paving on the north side.
3.3 Preliminary Subsurface Conditions
3.3.1 Soils
Based on the drilling performed, the subsurface soil conditions consist of fine-grained
surficial soils comprised of primarily sandy lean clay soils with occasional sandy silt and
clayey sand containing very high fines. These fine-grained soils overlie native clayey gravel
or clayey sand. Fill material generally consistent with the native soils and containing
construction debris were observed in a single boring (B-10). The borings indicate the
surficial clay and fill (when present) extend to depths of approximately 4 to 12 feet below
existing site grades. The underlying gravel and sand extend to depths of at least 31.8 feet,
and all borings were terminated in this material.
Given the amount of existing infrastructure and development within the proposed project
limits, we do anticipate additional areas of fill not identified by these investigations to be
encountered at various locations. While fill was only encountered in a single boring during
our investigations, it is typical of most site development projects and should be anticipated.
The fill material observed appears to be comprised of reworked native soils containing
construction debris and may be suitable for reuse during construction; however, depending
on the type and amount of construction debris or the presence of other deleterious materials
(organics, contamination, etc.), the materials may not be suitable for reuse and would
warrant removal from the site. Due to our inability to investigate close to existing structures,
the fill may not be identifiable until the start of construction and should be evaluated at that
time to determine if the material warrants removal or is suitable for reuse on the project.
North Central Development Site Conditions
Bozeman, Montana Page 7
The following is a summary of the subsurface conditions based on the subsurface
investigations and laboratory testing performed in May 2019 and September 2020.
Conditions across the site may vary from those shown on the attached borings logs and
within the discussion below.
FILL MATERIAL
Soil fill material was encountered in a single boring (B-10) located on the south end of the
parking lot in the northeast corner of Block 3. This boring was located at the high side of the
parking lot near the existing structure. The asphalt section is underlain by fill materials
visually classified as lean clay with sand and clayey sand with gravel extending to a depth of
approximately 6.6 feet below grade. This fill zone is highly heterogeneous and contained
visible construction debris, including brick, concrete, and wood fragments in the auger
spoils.
The existing asphalt surfacing and underlying base course gravels are also considered fill
material as they are not native to the site and were imported; however, they are of higher
quality and better controlled than most fill. Pavement sections were present at 6 of the 14
borings performed for this project. The asphalt ranged in thickness from 2.5 to 6.0 inches of
pavement. The underlying base course gravel extended to depths varying from 0.8 to 3.0
feet below existing site grade at pavement borings.
SURFICIAL FINE-GRAINED SOILS
The fine-grained surficial soils consist primarily of sandy lean clay; however, transitional
zones of clayey sand were encountered in three of the borings (B-9, B-12, and B-14) and
sandy silt was encountered in one boring (B-11). The fine-grained soils are generally soft
to firm as indicated by penetration resistance values, which ranged from 2 to 20 blows per
foot (bpf) but averaged only 6 bpf. Based on five consolidation tests and two unconfined
compression tests performed on samples of these materials, they are considered slightly to
highly compressible and relatively weak. The results of these tests are summarized below:
Table 1 – Summary of Unconfined & Consolidation Testing
Boring No. Sample Depth
(ft)
Unconfined
Compressive
Strength (psf)
Undrained
Shear
Strength (psf)
Sample
Compression
Under 4,000
psf loading
B-5 5.0 – 7.0 2,773 1,386 0.8%
B-7 5.0 – 6.0 ----- ----- 2.4%
B-9 5.0 – 6.0 1,865 933 3.5%
B-12 5.0 – 7.0 ----- ----- 3.4%
B-14 5.0 – 7.0 ----- ----- 1.8%
North Central Development Site Conditions
Bozeman, Montana Page 8
Nine samples of these materials were tested and contained between 0 and 25 percent
gravel, between 13 and 51 percent sand, and between 42 and 81 percent fines (clay and
silt). Ten additional samples exhibited liquid limits ranging from 32 to 49 percent and
plasticity indices ranging from 12 to 19 percent. The natural moisture contents varied from 7
to 31 percent and averaged 21 percent.
A composite sample of the material was tested in our laboratory to evaluate its compactive
properties in accordance with ASTM D698 and its strength when utilized as a pavement
subgrade using a California Bearing Ratio (CBR) test in accordance with ASTM D1883.
The results of these tests are shown below.
Table 2 – Summary of Proctor and CBR Testing
Maximum
Density (pcf)
Optimum Moisture
Content (%)
California Bearing
Ratio (CBR)
115.6 12.8 3.7% @ 90%
Compaction
NATIVE SAND AND GRAVEL
The surficial clays are were underlain in all 14 borings by native gravel with sand or clayey
sand with gravel. The native gravels are medium dense to very dense as indicated by
penetration resistance values, which ranged from 14 to greater than 100 bpf and averaged
65 bpf. Eleven samples of this material were tested and contained between 21 and 57
percent gravel, between 29 and 62 percent sand, and between 13 and 28 percent fines
(clay and silt). These gradations are not anticipated to be completely representative of the
actual in situ soil properties due to the inherent difficulties with sampling these soils using
drilling methods, which limit the size of rocks collected and cause mechanical breaking of
the rocks into smaller sizes. In situ materials are likely to be significantly gravellier than is
represented by these tests. The natural moisture contents varied from 3 to 28 percent and
averaged 13 percent based on the sample depth, clay content, and proximity to the ground
water table.
3.3.2 Ground Water
Ground water was encountered within all fourteen borings performed for this project. The
water depth and date of measurement for each boring are summarized in Table 3 on the
next page.
North Central Development Site Conditions
Bozeman, Montana Page 9
Table 3 – Summary of Initial Ground Water Depths
Boring No. Surface
Elevation (ft)*
Ground Water
Depth (ft)
Date of
Measurement
Ground Water
Elevation (ft)*
B-1 4798.0 11.8 5-22-2019 4786.2
B-2 4796.5 11.1 5-22-2019 4785.4
B-3 4799.9 12.5 5-21-2019 4787.4
B-4 4802.1 13.0 5-21-2019 4789.1
B-5 4799.9 14.1 9-15-2020 4785.8
B-6 4798.4 13.1 9-15-2020 4785.3
B-7 4801.2 14.2 9-15-2020 4787.0
B-8 4802.0 14.5 9-15-2020 4787.5
B-9 4797.5 13.3 9-16-2020 4784.2
B-10 4801.5 22.5 9-16-2020 4779.0
B-11 4805.9 14.0 9-16-2020 4791.9
B-12 4801.4 13.5 9-16-2020 4787.9
B-13 4801.5 13.3 9-17-2020 4788.2
B-14 4803.4 13.8 9-17-2020 4789.6
* The elevations reported above were collected using a handheld GPS unit. The accuracy of such units are generally ± 3 feet
vertically. The elevations reported are based on the Geoid12A (Conus) datum. It is the responsibility of others to verify these
elevations and make any necessary conversion to the project datum prior to use in any design or construction applications.
Four monitoring wells were installed in May 2019 (Borings B-1 through B-4) and since their
initial installation, 28 additional ground water measurements have been performed and are
summarized in Table 4 below.
Ground water readings in late 2019 are somewhat erratic, with significant changes from
week to week. The readings collected to date in 2020 appear more consistent and are likely
more representative of the actual ground water behavior. All four wells are exhibiting a
seasonal rise in the ground water table of approximately one foot. Overall global ground
water depths can change between seasons and from year to year. The actual seasonal
variations can change from year to year as well and may exceed fluctuations observed in
the wells since their installation.
North Central Development Site Conditions
Bozeman, Montana Page 10
Table 4 – Ground Water Monitoring Data
Date Depth of Water Measured (Feet)
B-1 B-2 B-3 B-4
6-3-2019 10.3 7.6 11.5 13.2
6-10-2019 11.0 11.0 11.6 13.3
6-17-2019 11.5 11.3 12.2 13.4
6-24-2019 12.1 11.7 12.3 11.7
7-1-2019 11.1 9.8 9.8 11.1
7-9-2019 11.8 11.9 13.0 11.5
7-15-2019 11.3 11.4 12.1 10.8
7-29-2019 12.2 12.4 12.8 10.0
8-6-2019 11.3 12.0 13.5 13.8
8-12-2019 12.0 11.7 13.1 13.8
8-19-2019 11.9 11.8 12.3 13.6
8-26-2019 12.1 11.8 12.8 14.0
4-7-2020 11.8 11.7 13.0 13.4
4-14-2020 11.8 11.6 13.1 13.5
4-22-2020 11.5 11.4 13.0 13.4
4-28-2020 11.6 11.6 13.0 13.5
5-5-2020 11.5 11.2 12.9 13.6
5-14-2020 11.5 11.3 12.6 13.4
5-19-2020 11.4 11.2 12.6 13.3
5-26-2020 11.4 11.1 12.3 13.3
6-3-2020 11.5 11.2 12.4 13.5
6-9-2020 11.3 11.0 12.2 13.0
6-16-2020 11.3 11.0 12.2 13.1
6-23-2020 11.2 10.8 12.0 13.0
7-7-2020 11.2 10.9 12.0 13.0
7-14-2020 11.4 11.0 12.2 13.2
7-22-2020 11.6 11.3 12.4 13.4
7-28-2020 11.7 11.4 12.6 13.5
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North Central Development Engineering Analysis
Bozeman, Montana Page 13
4.0 ENGINEERING ANALYSIS
4.1 Site Grading and Excavations
Based on our field work and experience in downtown Bozeman, fine-grained surficial soils
containing varying concentrations of sand are anticipated in the upper 4 to 12 feet of the site.
The surficial clay will be underlain by native clayey gravels with sand or clayey sand with gravel
extending to depths of greater than 30 feet. Due to the highly developed condition of the area
currently, we also anticipate surficial fill materials associated with pavement systems, general
site grading, and foundation backfill to be encountered. Such fill was encountered in several
borings and ranged in thickness from 0.5 to 6.6 feet. Most of these borings were limited to the
surficial pavement section and did not extend below 2.5 feet; however, one boring (B-10)
encountered site grading fill containing brick, concrete, wood, and other construction debris
below the pavement section and extending to a depth of 6.6 feet. Boring B-10 was located near
an existing building and likely in the building foundation backfill, indicating similar quality backfill
could be encountered throughout the site. The suitability of any fill materials to be reused will
need to be further evaluated during construction based on the type and amount of debris it
contains as well as potential for contamination and other factors.
Based on the ground water data collected, ground water should be below the depth of most
foundation and utility excavations for this project; however, ground water levels have historically
been located about 10 to 13 feet below existing site grades and may be encountered in deep
excavations associated with the demolition of existing basement, installation of new basements,
or deep utilities beneath basement systems. Seasonal fluctuation in the ground water should
also be expected.
Due to the relatively high ground water elevations, the use of storm water infiltration below
basement elevations will be problematic. This should be considered when preparing the storm
water and foundation designs for this project.
4.2 Foundation Systems
Based on the subsurface conditions observed during the site investigations performed for this
area, the use of conventional shallow foundations is considered suitable for the proposed
development areas, but varying types and degrees of subsurface improvement will be needed
to ensure the long-term performance of the structures. The surficial clay soils are considered
soft and highly compressible, making them unsuitable for the support of the anticipated multi-
story construction. Potential impacts of the clay soil can be mitigated using one of two methods.
• Complete removal of the clay zone down to the native gravels and replacement with
properly compacted structural fill.
• Installation of Engineered Aggregate Piers (EAPs) to improve subgrade conditions
and mitigate settlement of the clay zone.
North Central Development Engineering Analysis
Bozeman, Montana Page 14
• Other deep foundation methods used to bridge structural loads to competent
bearing material.
The best-suited approach will vary from structure to structure within the development and will be
controlled by the depth of the fine-grained soils, the design footing elevation (or depth), the
depth of existing foundations being removed (where applicable), and other factors. In our
experience, the use of complete removal and replacement methods are best suited to structures
where the overall clay thickness remaining beneath the foundations are less than three feet or
those where a significant portion of the new building footprint will already be removed and
backfilled as part of the existing structure demolition. In these cases, the cost of excavation and
imported structural fill is generally feasible for the project. Where clay thicknesses exceed three
feet beneath footings and where significant demolition of existing foundation is not necessary,
the use of EAP improvements may be a more economical alternative. EAP systems consist of
a series of drilled shafts extending to the native gravels in which densely compacted stone (or
structural fill) columns are installed. This process acts to reinforce the clay soils through
significant lateral stress increases, which reduce their compressibility and increase their
strength, thus allowing for the use of conventional shallow foundation systems. EAP methods
are proprietary and will require the involvement of a separate licensed EAP design-build
contractor.
Below we have looked at each section of the project separately and discussed the suitability of
each subgrade improvement method.
4.2.1 Block 4
Four borings were drilled within the limits of the Block 4 portion of the project and include B-
1, B-5, B-7, and B-8. Each of these borings encountered surficial sandy lean clay extending
to depths of approximately 6.0 to 8.2 feet. Thus, the northern three-quarters of the structure
which is planned to utilize a full-depth basement extending approximately ten feet below
grade, are expected to bear upon native gravels and should not warrant any additional
subsurface improvements. Footings for the southern portion of this structure are expected
to lie approximately two to four feet above the gravel surface. Due to the limited area for
this section of the structure, we would recommend using conventional remove and replace
methods for this area. It may be possible to reuse portions of the native gravel excavated
from the adjacent basement to reduce the volume of imported structural fill required.
4.2.2 Block 3
Six borings were drilled within the limits of the Block 3 portion of the project and include B-2,
B-3, B-4, B-6, B-9, and B-10. These borings exhibited greater variability in the depth of the
fine-grained surficial soils, and fill was encountered in one boring. For this portion of the
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Bozeman, Montana Page 15
project, the depth requiring soil improvement appears to range from 4.0 to 12.0 feet below
existing site grades. This portion of the site will also include the demolition and removal of
the existing structure, which is known to have a basement beneath at least part or all the
existing building’s footprint. At this time, specific locations for existing basements are not
known, and these will have a significant impact on the best foundation support system to
each of the planned structures. The removal of the existing building is anticipated to impact
all the proposed buildings except 3-4, which appears to lie primarily with the existing parking
lot. However, any buildings which do not overlie existing basements will likely not be
disturbed significantly below the planned footing elevation.
Buildings 3-4 and 3-5 are planned to utilize basements which will bear approximately ten
feet below existing site grade. Thus, most of these structures will bear within or very near
the native gravel surface and would be best suited to the use of simple remove and replace
methods. Structural fill thickness ranging from zero to four feet could be required depending
on the final grading and finished floor elevation for these structures.
Buildings 3-1, 3-2, and 3-3 are all planned to be conventional slab-on-grade structures with
no below-grade space and will lie over portions of the existing building foundation, which is
to be demolished. Based on our estimates, it appears that at least half of the overall
footprint for each of these structures will overlie the existing structure. We are not clear on
how much of the existing structure includes a full depth basement; however, assuming the
entire structure currently has a basement a significant area of each new structure could
require demolition and backfill with structural fill. Given the magnitude of the structural fill
anticipated beneath these structures as part of the demolition process, we believe extending
the excavations throughout the remainder of the building footprints may be the most
economical, pending additional information regarding the location and elevation of existing
basements within the existing structure. We are available to assist in determining the most
appropriate foundation for each structure. However, the added cost of the excavation
imported structural fill, and complexities of excavating to the required depths close to
existing roadways need to be considered. These structures would also benefit from the
inclusion of full-depth basements as an alternative.
4.2.3 Mountain View
Four borings were drilled within the limits of the Mountain View portion of the project and
include B-11 through B-14. Each of these borings encountered fine-grained surficial soils
extending to depths of approximately 6.5 to 8.1 feet below existing site grades. This portion
of the site will also include the demolition and removal of the existing structure, which has a
partial basement beneath the east half of the structure. Both planned structures are to
utilize slab-on-grade construction with no below-grade spaces. Thus, assuming a finished
floor elevation for the structures which are close to that of the existing building and
conventional frost depth foundations (four-foot below finished ground surface), structural fill
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Bozeman, Montana Page 16
thicknesses of up to four feet could be required using conventional remove and replace
methods. The need for over-excavation and backfill anticipated for the demolition of the
existing basement is expected to be isolated to the eastern structure within the Mountain
View portion of the project only. This is the larger of the planned structures and the existing
basement appears to encompass a significant portion of the new building footprint. For this
reason, the extension of the over-excavation and replacement beneath the east Mountain
View structure is anticipated to be the best option for this building.
Demolition of the existing foundation on the west side of this phase is not anticipated to be
significantly deeper than the foundation of the planned construction. Thus, given the depth
of the native gravel, the use of EAP improvements may be better suited to this particular
building.
4.2.4 Summary
Overall, given the intended configuration of the planned structures, the need for demolition
and filling of existing basement excavations, and the subsurface conditions encountered, we
believe that the use of conventional over-excavation to native gravels and replacement with
compacted structural fill is best suited for most of the structures on this project. Those
structures which are not currently planned to incorporate a basement would generally
benefit from its inclusion by significantly reducing or eliminating the need for structural fill
within their footprints.
Based on our assessment, we believe some limited structures could be more economically
constructed use EAP improvements. EAP systems are not warranted beneath any
structures planned to utilize a basement. Beneath others, the EAPs would either be utilized
solely beneath those portions which do not require removal of the existing foundations or
could be utilized beneath the entire building footprint after the existing foundations have
been removed and backfilled. The latter option is anticipated to add additional cost to the
project; however, the use of a partial EAP system has the potential for greater differential
movements resulting from variations in the performance of the various support methods.
4.3 Slab-on-Grade Construction
The native fine-grained soils encountered in the borings are generally soft and compressible but
not expected to exhibit significant expansive concerns. While slab systems supported over
these materials would be susceptible to settlement, none of the slabs for these structures are
expected to be heavily loaded.
Exterior flatwork associated with site infrastructure are typically relatively inexpensive to repair
or replace if excessive movements occur; thus, conventional slab-on-grade construction
consisting of a thin cushion course overlying native clay soils is common for these exterior
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Bozeman, Montana Page 17
features. However, if critical exterior flatwork is planned for which vertical movements would be
detrimental to its function a higher level of care should be considered.
Interior slab systems for structures are much more costly and intrusive to repair or replace later
due to excessive settlements. Thus, these elements warrant a higher level of care. The highest
level of performance will be obtained through the same methods discussed in Section 3.2 above
for foundation systems, and such methods are suitable if the Owner is unable to accept any risk
of slab settlements. However, based on the conditions encountered, we believe that lightly
loaded interior slabs (max live load of 100 psf) could utilize lesser improvements and still
achieve a suitable level of performance. Such interior, lightly loaded slab systems can be
supported on at least 18 inches of properly compacted structural fill separated from the
underlying native soils using a woven geotextile. This geotextile will maintain separation of the
clay soils from the structural fill and add reinforcement to help aid in the proper compaction of
the overlying structural fill. Interior slabs supported as described are not anticipated to realize
settlements exceeding ¾-inch. When basement foundations are considered, native gravels
may be encountered within the specified 18-inch depth beneath slab systems. Construction can
exclude the geotextile when the structural fill beneath slabs extends to native gravels.
4.4 Pavement Systems
A pavement section is a layered system designed to distribute concentrated traffic loads to the
subgrade. Performance of the pavement structure is directly related to the physical properties of
the subgrade soils and the magnitude and frequency of traffic loadings. Pavement design
procedures are based on strength properties of the subgrade and pavement materials, along
with the design traffic conditions. Based on the preliminary site plan, new asphalt pavements
anticipated with this project are limited to access roads between the building within Block 3. No
specific information regarding the vehicle use of the pavements has been provided but based
on the limited width and our understanding of the intended use of these structures, we have
assumed that the vehicle traffic will be primarily passenger type vehicles and that no significant
truck traffic will be using these areas. We do anticipate some impact to the existing city streets
associated with demolition and new construction activities. However, we have assumed that all
replacement areas will match the existing roadway section or the minimum standards require by
the City of Bozeman Street Cut Permit and we have not provided recommendations for those
repairs at this time.
The anticipated subgrade material within Block 3 is soft clay soils and possible fill soils
consisting of clayey sand with gravel. These materials are classified as A-6 soils in accordance
with the American Association of State Highway and Transportation Officials (AASHTO)
classification. AASHTO considers this soil type to be a relatively poor subgrade due to the
limited drainage properties, reduced strength when wetted, and frost susceptibility. Typical
California Bearing Ratio (CBR) values for this type of soil range from 3 to 5 percent when the
material can be properly compacted. Laboratory testing was performed on a bulk sample of the
native materials to evaluate the CBR. The initial proctor test indicates that the optimum
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Bozeman, Montana Page 18
moisture content for compaction of the clay material is approximately 13 percent; however, the
average moisture content with clay within the project limits was 21 percent. This indicates that
the clay is likely to be well above optimum, which will prevent high levels of subgrade
compaction from being achieved, which will, in turn, result in a slower CBR value. Using the
Proctor curve as a guide, at a moisture content of approximately 21 percent, the maximum
compaction that should be achievable is around 87 percent. The CBR test report shown in the
appendix, with a value of 3.7 percent, is based on a minimum compaction requirement of 90
percent. However, point one of the tests was at a relative compaction level of 87.2 percent and
resulted in a CBR of only 2.5 percent at 0.2-inch penetration. These points most closely match
the anticipated conditions during construction; thus, our pavement section has been prepared
using a CBR value of 2.5 percent.
Given the soft clay soils expected for pavement subgrades, the inclusion of a geotextile
between the prepared subgrade and the pavement section gravels is recommended. Various
products are available, and some will provide only separation, while others provide
reinforcement to help reduce the overall gravel section required. We have included two
sections for your consideration using both alternatives.
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Bozeman, Montana Page 19
5.0 RECOMMENDATIONS
5.1 Site Grading and Excavations
1. All topsoil and organic material, asphalt, concrete and related construction debris associated
with the demolition of the existing structures should be removed from the proposed building
and pavement areas and any areas to receive site grading fill.
2. All fill and backfill should be non-expansive, free of organics, and debris and should be
approved by the project geotechnical engineer. The on-site soils, exclusive of topsoil and
existing uncontrolled fill materials, are suitable for use as backfill and general site grading fill
on this project. All materials should be placed in uniform lifts not exceeding 8 inches in
thickness for fine-grained soils and not exceeding 12 inches for granular soils. All materials
compacted using hand compaction methods or small walk-behind units should utilize a
maximum lift thickness of 6 inches to ensure adequate compaction throughout the lift. All fill
and backfill shall be moisture conditioned to near the optimum moisture content and
compacted to the following percentages of the maximum dry density determined by a
standard proctor test, which is outlined by ASTM D698 or equivalent (e.g. ASTM D4253-
D4254).
a) Structural Fill Below Foundations (Section 5.2 ONLY) ............... 98%
b) Structural Fill Below Slab-on-Grade Construction ...................... 98%
c) Exterior Foundation Wall Backfill ................................................. 95%
d) Below Paved Areas ..................................................................... 95%
e) General Landscaping or Nonstructural Areas ............................. 92%
f) Utility Trench Backfill .................................................................... 95%
For your consideration, native fine-grained soils are anticipated to be at moistures contents
well above the optimum for compaction and significant moisture conditioning of these
materials may be required prior to use. This often requires abundant space where the soils
can be worked and can be difficult during times of the year when precipitation occurs
frequently. Thus, the use of imported materials for backfill may be more cost-effective at
times. Furthermore, verification of compaction requires laboratory proctor tests to be
performed on a representative sample of the soil prior to construction. These tests can
require up to one week to complete (depending on laboratory backlog), and this should be
considered when coordinating the construction schedule to ensure that delays in
construction or additional testing expense is not required due to laboratory processing times
or rush processing fees.
3. Imported structural fill should be non-expansive, free of organics and debris, and conform to
the material requirements outlined in Section 02234 of the Montana Public Works Standard
Specifications (MPWSS). All gradations outlined in this standard are acceptable for use on
this project; however, conventional proctor methods (outlined in ASTM D698) shall not be
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Bozeman, Montana Page 20
used for any materials containing less than 70 percent passing the ¾-inch sieve.
Conventional proctor methods are not suitable for these types of materials, and the field
compaction value must be determined using a relative density test outlined in ASTM D4253-
4254.
4. Develop and maintain site grades, which will rapidly drain surface and roof runoff away from
foundation and subgrade soils, both during and after construction. The final site grading
shall conform to the grading plan prepared by others to satisfy the minimum requirements of
the applicable building codes.
5. It is the responsibility of the Contractor to provide safe working conditions in connection with
underground excavations. Temporary construction excavations greater than four feet in
depth, which workers will enter, will be governed by OSHA guidelines given in 29 CFR, Part
1926. The soil conditions on site can change due to changes in soil moisture or
disturbances to the site prior to construction. Thus, the Contractor is responsible to provide
an OSHA knowledgeable individual during all excavation activities to regularly assess the
soil conditions and ensure that all necessary safety precautions are implemented and
followed.
5.2 Conventional Shallow Foundations on Structural Fill
The design and construction criteria below should be observed for a shallow foundation
system bearing on properly compacted structural fill extending to native gravels. With this
option, the complete removal of the native clay to the gravel surface shall be performed and
compacted structural fill installed back to the design footing elevation. Based on the
intended configuration of the proposed structures, anticipated demolition and filling of old
foundations, and the subsurface conditions encountered, we believe this approach is best
suited for most of the proposed structures on this project as discussed in Section 4.2 above.
6. Both interior and exterior footings should bear on properly compacted structural fill
extending to approved native gravels. All structural fill shall be placed and compacted in
accordance with item 2 above and conform to the material requirements of Item 3. The
limits of removal and replacement with compacted structural fill shall extend at least one foot
beyond the outer face of the footings in all directions. Footings supported as described
should be designed with a maximum allowable soil bearing pressure of 5,000 psf, and a
one-third increase in the bearing pressure is acceptable for consideration of transient load
cases. Such construction is expected to realize total settlements of less than ¾-inch with
differential settlements of approximately one-half this amount.
7. Footings shall be sized to satisfy the minimum requirements of the applicable building codes
while not exceeding the maximum allowable bearing pressure provided in Item 6 above.
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8. Exterior footings and footings beneath unheated areas should be placed at least 48 inches
below finished exterior grade for frost protection.
9. Lateral loads are resisted by sliding friction between the footing base and the supporting soil
and by lateral pressure against the footings opposing movement. For design purposes, a
friction coefficient of 0.45 and a lateral resistance pressure of 150 psf per foot of depth are
appropriate for foundations bearing on properly compacted structural fill (Item 3) and
backfilled with processed and compacted on-site soils.
10. A representative of TD&H Engineering should be retained to observe construction
excavations, verify that all excavations have reached suitable native gravels, and verify the
placement and compaction of the structural fill in accordance with these recommendations.
11. Ground water may be encountered in some excavations required for the complete removal
of the fine-grained soils depending on the time of year and the magnitude of seasonal
ground water fluctuations. The Contractor should be prepared to dewater excavations as
needed to facilitate the removal of the fine-grained soils and the proper installation and
compaction of the subsequent structural fill.
5.3 Conventional Shallow Foundations Over EAP Improved Soils
EAP systems may be preferred on limited structures located outside of basement areas of
existing structures to be demolished. When used, the EAP design must be performed by a
licensed design/build contractor. We would recommend consulting either GeoTech Foundation
Company (GTFC – West), First Mark Construction, Keller North America, or Montana Helical
Pier for the design and installation of such services. The recommendations below are intended
to be preliminary guidelines based on our experience with this system. These
recommendations shall not be utilized for final design of the foundation system without being
verified by a licensed EAP designer.
12. Both interior and exterior footings should bear on EAP improved soils and be designed
using the maximum allowable bearing pressure to be issued by the EAP designer. For
preliminary planning purposes, we understand that an allowable soil bearing pressure of
approximately 4,000 to 6,000 psf is typical for these systems. EAP elements are anticipated
to be 24 to 30 inches in diameter with lengths extending down into the native gravel stratum.
However, alternative EAP sizes may be specified by the designer of record based on their
analysis. Any compacted gravel specified by the EAP designer as a capping substrate shall
be compacted and installed per the EAP designer requirements.
13. Footings shall be sized to satisfy the minimum requirements of the applicable building codes
while not exceeding the maximum allowable bearing pressures provided by the EAP
designer.
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Bozeman, Montana Page 22
14. Exterior footings and footings beneath unheated areas should be placed at least 48 inches
below finished exterior grade for frost protection unless otherwise specified by the EAP
designer.
15. Lateral loads are resisted by sliding friction between the footing base and the supporting soil
and by lateral pressure against the footings opposing movement. For design purposes, a
preliminary friction coefficient of 0.5 is typical of EAP improved soils; however, this value
shall be verified by the EAP designer during the final design process. A lateral resistance
pressure of 150 psf per foot of depth is appropriate for exterior backfill consisting of
processed and compacted on site soils.
16. The EAP designer/installer typically provides their own internal quality control system;
however, the International Building Code (IBC) considers EAPs to be a form of deep
foundation which require full-time inspection. We recommend that a representative of
TD&H Engineering be retained to provide third-party construction observation on a full-time
basis during the installation of EAP elements to verify compliance with the design
documents.
17. Dewatering systems may be required, as specified by the EAP designer based on the
method of construction and element depth planned for the EAP system.
5.4 Foundation Walls
18. Backfill should be selected, placed, and compacted per Item 2 above. Care should be taken
not to over-compact the backfill since this could cause excessive lateral pressure on the
walls. Only hand-operated compaction equipment should be used within 5 feet of foundation
walls.
19. Basement walls, when utilized, which are laterally supported and can be expected to
undergo only a slight amount of deflection should be designed for a lateral earth pressure
computed on the basis of an equivalent fluid unit weight of 75 pcf for backfill consisting of
processed and moisture conditioned fine-grained soils. If native gravels or structural fill are
to be utilized as foundation backfill, a reduced equivalent fluid unit weight of 60 pcf is
appropriate.
For consideration of seismic forces, a seismic equivalent fluid unit weight of 100 pcf or 80
pcf is appropriate for the increased lateral forces associated with earthquake motions for
backfill consisting of processed and moisture conditioned fine-grained soils or native gravels
and structural fill, respectively.
20. Exterior footing drains are only required for structures which incorporate a below-grade
space (basement, crawlspace, etc.) or any structure in which the interior floor elevation is
set lower than the finished exterior grade.
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Bozeman, Montana Page 23
When required, drains should consist of a minimum 3-inch diameter, geotextile-wrapped,
flexible, slotted pipe (ADS) or perforated, SDR 35, 4-inch diameter, PVC drain tile in poorly-
graded gravel with geotextile placed at or below exterior footing grade. Drains shall be
covered by at least 12 inches of free-draining, open-graded, granular material. The open-
graded granular material should be enveloped in a geotextile to prevent the migration of
fines. Use of a single piece of geotextile with a full-width lap at the top is preferred;
however, two separate pieces of fabric may be used provided a minimum overlap distance
of 12 inches is maintained at all joints. Drains should be sloped to the site storm water
system. A typical perimeter foundation drain is shown on Construction Standard
No. 02801-06C.
21. Due to potential ground water fluctuations, it is recommended that all basement foundation
walls be water-proofed in accordance with the applicable sections of the International
Building Code (IBC).
5.5 Exterior Concrete Flatwork
22. For normally loaded, exterior concrete flatwork, the fine-grained (clay and silt) soils and
limited fill encountered may pose some risk to the performance of these features due to the
compressibility and frost susceptibility of these materials. Conventional construction
consisting of approximately four to six inches of free-draining, crushed gravel placed
beneath the concrete and compacted to the requirements of Item 2 above is considered
suitable provided the Owner is aware of and willing to accept the risks associated with this
construction method. The magnitude of displacement will vary depending on the depth of
the fine-grained soils at the location as well as drainage conditions, irrigation locations, slab
loading conditions, and other factors. Slab movements could result in the need for more
frequent repair or replacement of the exterior concrete if they become too great.
23. If the Owner desires to reduce the risk of movements beneath exterior slab systems and
improve anticipated performance, a variety of measures are possible, and these can be
discussed with the design team. Mitigative efforts can range from the use of a greater base
course thickness to the complete removal and replacement of the problematic soil. The
various options need to be considered by the Owner based on the performance to cost
relationship so they can select the most appropriate system for their project.
5.6 Interior Concrete Floor Slabs
The recommendations outlined below are the minimum improvements recommended beneath
interior slab systems when EAP improvements are considered in lieu of the complete removal
and replacement method discussed in Section 5.2. These minimum improvements are intended
to achieve a suitable level of slab performance and are not intended to eliminate the risk of slab
settlement.
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Bozeman, Montana Page 24
24. For conventional lightly loaded, interior slab-on-grade construction used in conjunction with
EAP improvements beneath foundation systems, slabs should be underlain by a minimum
of 18 inches of properly compacted structural fill (Items 2 and 3), which is separated from
the underlying native soils by a woven Mirafi RS 580i geotextile. The native fine-grained
soils are anticipated to be at elevated moistures which are not conducive to compaction;
thus, subgrade preparation should be limited to removing excess soil debris to provide a
smooth surface on which the geotextile can be installed.
Any washed rock or similar material desired beneath the slabs for plumbing installation
would be in addition to the specified structural fill thickness. If native gravels are
encountered within the minimum depth of the structural fill (i.e. basement slabs), the
geotextile may be omitted, and the structural fill thickness reduced to that required to reach
the native gravels.
25. Concrete floor slabs should be designed using a modulus of vertical subgrade reaction
no greater than 125 pci when designed and constructed as recommended in Item 24
above.
26. Geotechnically, an underslab vapor barrier is recommended beneath all basement slabs on
this project due to the potential for ground water fluctuations and proximity to elevated soil
moistures. A vapor barrier is normally used to limit the migration of soil gas and moisture
into occupied spaces through floor slabs. The need for a vapor barrier in other applications
beyond full-depth basements should be determined by the architect and/or structural
engineer based on interior improvements and/or moisture and gas control requirements.
5.7 Pavements
27. The following pavement section or an approved equivalent section should be selected in
accordance with the discussions in the Engineering Analysis.
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Bozeman, Montana Page 25
Table 5 – Recommended Asphalt Sections
Pavement Component
Component Thickness
Option 1 -
Separation
Option 2 -
Reinforcing
Asphaltic Concrete Pavement 3” 3”
Crushed Base Course 6” 6”
Crushed Subbase Course 21” 12”
Geotextile Type Separation (Item 31) Reinforcing (Item 32)
Total 30” 21”
** The pavement sections summarized above have not considered vehicle loads associated with construction activities and are
not intended to be utilized by the Contractor during construction for access to concrete trucks, cranes, or other heavy
equipment. Additional assessment of improvements to support such traffic would be needed and is beyond the scope of this
report.
28. Final pavement thicknesses exceeding 3 inches shall be constructed in two uniform lifts.
29. Crushed base courses shall conform to the material properties outlined in Section 02235 of
the Montana Public Works Standard Specifications (MPWSS). All gradations outlined in this
specification are acceptable for this application based on the local availability and contractor
preference.
Crushed subbase courses shall conform to material properties outlined in Section 02234 of
the MPWSS. All gradations outlined in this specification are acceptable for this application
based on local availability and contractor preference.
30. Where the existing grades will be raised more than the thickness of the pavement section,
all fill should be placed, compacted, and meet the general requirements given in Item 2
above. This may require moisture conditioning if native soils are used for general site
grading fill.
31. The first option shown in Table 5 above utilizes a standard separation geotextile between
the fine-grained subgrade and the gravels associated with the pavement section. This
material is not intended to add strength to the section to reduce gravel thicknesses and is
only utilized to keep the two materials separate and help ensure the long-term drainage
properties of the gravels. The use of a Mirafi 180N is recommended for this application, and
the gravel thickness shown in Option 1 above.
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Bozeman, Montana Page 26
32. The subbase thickness shown in Table 5 above for Option 2 reflects the increased stability
and reinforcement provided by a high modulus reinforcing geotextile. With this option, the
use of a Mirafi RS580i is appropriate for the subgrade conditions and the gravel section
thicknesses outlined above.
33. Prior to geotextile installation for either option, the subgrade must be cleared of all loose soil
and statically rolled to provide a smooth, relatively level surface. Alternative geotextiles or
geogrids other than those called out in Items 31 and 32 above must be evaluated
individually and may result in increased subbase thickness to achieve a similar level of
performance.
34. Ideally, the asphaltic cement should be a Performance Graded (PG) binder having the
following minimum high and low-temperature values based on the desired pavement
reliability.
Reliability Min. High
Temp Rating
Min. Low
Temp Rating Ideal Oil Grade
50% 33.8 -30.6 PG 52-34
98% 37.5 -39.4 PG 52-40
However, based on our experience, neither of these materials are available through local
suppliers, and significant additional expense would be realized using these products. Thus,
we recommend the use of a PG 58-28 oil for any asphalt pavement included in this project.
Of the locally available products, this material will provide the highest level of performance
in our climatic conditions.
5.8 Continuing Services
Three additional elements of geotechnical engineering service are important to the successful
completion of this project.
35. Consultation between the geotechnical engineer and the design professionals during the
design phases is highly recommended. This is important to ensure that the intentions of our
recommendations are incorporated into the design and that any changes in the design
concept consider the geotechnical limitations dictated by the on-site subsurface soil and
ground water conditions.
36. Observation, monitoring, and testing during construction is required to document the
successful completion of all earthwork and foundation phases. A geotechnical engineer from
our firm should be retained to observe the excavation, earthwork, and foundation phases of
the work to determine that subsurface conditions are compatible with those used in the
analysis and design. If construction services are performed by someone other than our firm,
the entities performing these services must be directed to contact us immediately upon
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Bozeman, Montana Page 27
changes in subsurface conditions so we may re-evaluate our recommendations in a timely
manner.
37. During site grading, placement of all fill and backfill should be observed and tested to
confirm that the specified density has been achieved. We recommend that the Owner
maintain control of the construction quality control by retaining the services of an
experienced construction materials testing laboratory. We are available to provide
construction inspection services as well as materials testing of compacted soils and the
placement of Portland cement concrete and asphalt. In the absence of project-specific
testing frequencies, TD&H recommends the following minimum testing frequencies be used:
Compaction Testing
Beneath Column Footings 1 Test per Footing per Lift
Beneath Wall Footings 1 Test per 50 LF of Wall per Lift
Beneath Slabs 1 Test per 1,500 SF per Lift
Foundation Backfill 1 Test per 100 LF of Wall per Lift
Parking Lot & Access Roads 1 Test per 2,500 SF per Lift
LF = Lineal Feet SF = Square Feet
North Central Development Summary of Field & Laboratory Studies
Bozeman, Montana Page 28
6.0 SUMMARY OF PRELIMINARY FIELD AND LABORATORY STUDIES
6.1 Field Explorations
The field exploration included two separate geotechnical investigations. A preliminary site
investigation was conducted on May 21 and 22, 2019. A total of four borings were drilled and
completed as monitoring wells during this preliminary study. The boring depths ranged from
28.5 to 31.2 feet at the approximate locations shown on Figure 1 to observe subsurface soil and
ground water conditions. Subsequently, on September 15 through 17, 2020, a final site
investigation consisting of ten additional borings was performed. Borings for this investigation
were drilled to depths of 28.5 to 31.8 feet. The borings for both investigations were advanced
through the subsurface soils using a truck-mounted Mobile B-61 drill rig equipped with 8-inch
hollowstem augers. All borings were logged by Mr. Craig Nadeau, PE of TD&H Engineering.
The location and elevation of the borings were recorded using a Trimble handheld GPS unit.
The locations shown on Figure 1 are accurate to within approximately 18 inches of the actual
field location; however, elevations can vary by approximately three feet (plus/minus) with GPS
methods. The elevations reported for the borings are based on the Geoid12A (Conus) datum.
These elevations require confirmation by other means and adjustment to the appropriate project
datum prior to utilizing the reported values in any design or construction applications.
Samples of the subsurface materials were taken using 1⅜-inch I.D. split spoon samplers. The
samplers were driven 18 inches, when possible, into the various strata using a 140-pound drop
hammer falling 30 inches onto the drill rods. For each sample, the number of blows required to
advance the sampler each successive six-inch increment was recorded, and the total number of
blows required to advance the sampler the final 12 inches is termed the penetration resistance
(“N-value”). This test is known as the Standard Penetration Test (SPT) described by ASTM
D1586. Penetration resistance values indicate the relative density of granular soils and the
relative consistency of fine-grained soils. Logs of each soil boring, which include soil
descriptions, sample depths, and penetration resistance values, are presented on the Figures 2
through 15.
Measurements to determine the presence and depth of ground water were made in the borings
by lowering an electronic water sounder through the open boring or auger shortly after the
completion of drilling. The depths or elevations of the water levels measured if encountered,
and the date of measurement are shown on the boring logs. Subsequent ground water
monitoring data is summarized in the report.
6.2 Laboratory Testing
Samples obtained during the field exploration were returned to our materials laboratory, where
they were observed and visually classified in general accordance with ASTM D2487, which is
based on the Unified Soil Classification System. Representative samples were selected for
North Central Development Summary of Field & Laboratory Studies
Bozeman, Montana Page 29
testing to determine the engineering and physical properties of the soils in general accordance
with ASTM or other approved procedures.
Tests Conducted: To determine:
Natural Moisture Content Representative moisture content of soil at the time of
sampling.
Grain-Size Distribution Particle size distribution of soil constituents describing the
percentages of clay/silt, sand and gravel.
Atterberg Limits A method of describing the effect of varying water content on
the consistency and behavior of fine-grained soils.
Consolidation Measurements of the percent compression experienced
under various loading conditions. For use in settlement
analysis and foundation design.
Unconfined Compression Undrained shear strength properties of cohesive soils
determined in the laboratory by axial compression.
Moisture-Density Relationship A relationship describing the effect of varying moisture
content and the resulting dry unit weight at a given
compactive effort. Provides the optimum moisture content
and the maximum dry unit weight. Also called a Proctor
Curve.
California Bearing Ratio The measure of a subgrade’s or granular base’s ability to
resist deformation due to penetration during a saturated
condition. Used to assist in pavement thickness designs.
The overall laboratory testing program between both investigations consisted of 117 moisture-
visual analyses, 20 sieve (grain-size distribution) analyses, and 10 Atterberg Limits analyses.
The results of the water content analyses are presented on the preliminary boring logs, Figures
2 through 15. The grain-size distribution curves and Atterberg limits are presented on Figures
16 through 45. In addition, five consolidation tests, two unconfined compression tests, one
proctor (moisture-density) test, and one California Bearing Ratio (CBR) test were performed.
The consolidation and unconfined compression results are presented on Figures 46 through 52.
The CBR and moisture density relationship are shown on Figures 53 and 54.
North Central Development Limitations
Bozeman, Montana Page 30
7.0 LIMITATIONS
This report has been prepared in accordance with generally accepted geotechnical engineering
practices in this area for use by the client for design purposes. The findings, analyses, and
recommendations contained in this report reflect our professional opinion regarding potential
impacts the subsurface conditions may have on the proposed project and are based on site
conditions encountered. Our analysis assumes that the results of the exploratory borings are
representative of the subsurface conditions throughout the site, that is, that the subsurface
conditions everywhere are not significantly different from those disclosed by the subsurface study.
Unanticipated soil conditions are commonly encountered and cannot be fully determined by a
limited number of soil borings and laboratory analyses. Such unexpected conditions frequently
require that some additional expenditures be made to obtain a properly constructed project.
Therefore, some contingency fund is recommended to accommodate such potential extra costs.
The recommendations contained within this report are based on the subsurface conditions
observed in the borings and are subject to change pending observation of the actual subsurface
conditions encountered during construction. TD&H cannot assume responsibility or liability for the
recommendations provided if we are not provided the opportunity to perform limited construction
inspection and confirm the engineering assumptions made during our analysis. A representative of
TD&H should be retained to observe all construction activities associated with subgrade
preparation, foundations, and other geotechnical aspects of the project to ensure the conditions
encountered are consistent with our assumptions. Unforeseen conditions or undisclosed changes
to the project parameters or site conditions may warrant modification to the project
recommendations.
Long delays between the geotechnical investigation and the start of construction increase the
potential for changes to the site and subsurface conditions, which could impact the applicability of
the recommendations provided. If site conditions have changed because of natural causes or
construction operations at or adjacent to the site, TD&H should be retained to review the contents of
this report to determine the applicability of the conclusions and recommendations provide
considering the time-lapse or changed conditions.
Misinterpretation of the geotechnical information by other design team members is possible and can
result in costly issues during construction and with the final product. Our geotechnical engineers
are available upon request to review those portions of the plans and specifications which pertain to
earthwork and foundations to determine if they are consistent with our recommendations and to
suggest necessary modifications as warranted. This service was not included in the original scope
of the project and will require additional fees for the time required for specification and plan
document review and comment. In addition, TD&H should be involved throughout the construction
process to observe construction, particularly the placement and compaction of all fill, preparation of
all foundations, and all other geotechnical aspects. Retaining the geotechnical engineer who
prepared your geotechnical report to provide construction observation is the most effective method
of managing the risks associated with unanticipated conditions.
North Central Development Limitations
Bozeman, Montana Page 31
This report was prepared for the exclusive use of the Owner and architect and/or engineer in the
design of the subject facility. It should be made available to prospective contractors and/or the
Contractor for information on factual data only and not as a warranty of subsurface conditions such
as those interpreted from the boring logs and presented in discussions of subsurface conditions
included in this report.
Prepared by: Reviewed by:
Craig Nadeau PE Kyle Scarr PE
Geotechnical Manager Regional Office Manager
TD&H ENGINEERING TD&H ENGINEERING
1
B O R I N G L O C A T I O N M A P
B O Z E M A N , M O N T A N A
N O R T H C E N T R A L G E O T E C H
CJS
9/29/20B20-068
FIGURE
??
?
?
?
??
?
?
?
?
?
?
?
B-5ELEV.= 4799.9 B-6ELEV.= 4798.4
B-7ELEV.= 4801.2
B-8ELEV.= 4802
B-4ELEV.= 4802.1
B-1ELEV.= 4798 B-9ELEV.= 4797.5
B-10ELEV.= 4801.5
B-2ELEV.= 4796.5
B-3ELEV.= 4799.9
B-11ELEV.= 4805.9
B-12ELEV.= 4801.4
B-13ELEV.= 4801.5
B-14ELEV.= 4803.4 ³
0 40 8020
Feet
1 8 0 0 R I V E R D R . N O . • G R E A T F A L L S , M O N T A N A 5 9 4 0 1
J :\2 0 2 0 \B 2 0 -0 6 8 N o r t h C e n t r a l G e o t e c h \C A D D \C I V I L \B 2 0 -0 6 8 B O R I N G S .m x d
B20-068 BORINGS.MXD
DRAWN BY:DESIGNED BY:QUALITY CHECK:DATE DRAWN:JOB NO.:FIELDBOOK:
R E V
D A T E
R E V I S I O N
4 0 6 .7 6 1 .3 0 1 0 • t d h e n g i n e e r i n g .c o m
?BORING LOCATION
PROJECT LOCATION
Service Layer Credits: U.S. Department of Agriculture Farm Services Agency Aerial Photography Field Office.National Geographic, Esri, Garmin, HERE, UNEP-WCMC, USGS, NASA, ESA, METI, NRCAN, GEBCO, NOAA, increment P Corp.
0
2.5
5
7.5
10
12.5
15
17.5
TOPSOIL: Sandy Lean CLAY, appears soft, brown,
moist
Sandy Lean CLAY, very soft, brown, moist
Clayey GRAVEL with Sand, medium dense to very
dense, brownish gray, slightly moist to wet
0.5
8.2
1-1-1
7-13-9
12-50/
5"
50/5"
50/5"
50/5"
LEGEND LOG OF SOIL BORING B-1SPT blows per foot Atterberg Limits
Field Moisture content North Central Development
Bozeman, MontanaGroundwater Level
Grab/composite sample
1-3/8-inch I.D. split spoon Logged by:Craig Nadeau, PE
2-1/2-inch I.D. split spoon Drilled by:O'Keefe Drilling
Truck-mounted Mobile B-61 with 8-inch HSA2-1/2-inch I.D. ring sampler GNP = Granular and Nonplastic
3-inch I.D. thin-walled sampler Note: The stratification lines represent approximate
boundaries between soil types. Actual boundaries
may be gradual or transitional.
May 22, 2019 B20-068-001
No sample recovery Figure No. 2
Sheet
GR
A
P
H
I
C
LO
G
SOIL DESCRIPTION
SURFACE:Irrigated Lawn
SURFACE ELEVATION:4,798.0 feet
DE
P
T
H
(
F
T
)
GR
O
U
N
D
WA
T
E
R
SP
T
B
L
O
W
CO
U
N
T
S
SA
M
P
L
E
DE
P
T
H
(
F
T
)
PENETRATION RESISTANCE/MOISTURE CONTENT
0 10 20 30 40 50 = BLOWS PER FOOT
= MOISTURE CONTENT
1 of 2
20
22.5
25
27.5
30
32.5
35
Bottom of Boring - Piezometer Installed
28.5
14-23-
45
50/6"
68
50/6"
LEGEND LOG OF SOIL BORING B-1SPT blows per foot Atterberg Limits
Field Moisture content North Central Development
Bozeman, MontanaGroundwater Level
Grab/composite sample
1-3/8-inch I.D. split spoon Logged by:Craig Nadeau, PE
2-1/2-inch I.D. split spoon Drilled by:O'Keefe Drilling
Truck-mounted Mobile B-61 with 8-inch HSA2-1/2-inch I.D. ring sampler GNP = Granular and Nonplastic
3-inch I.D. thin-walled sampler Note: The stratification lines represent approximate
boundaries between soil types. Actual boundaries
may be gradual or transitional.
May 22, 2019 B20-068-001
No sample recovery Figure No. 2
Sheet
GR
A
P
H
I
C
LO
G
SOIL DESCRIPTION
SURFACE:Irrigated Lawn
SURFACE ELEVATION:4,798.0 feet
DE
P
T
H
(
F
T
)
GR
O
U
N
D
WA
T
E
R
SP
T
B
L
O
W
CO
U
N
T
S
SA
M
P
L
E
DE
P
T
H
(
F
T
)
PENETRATION RESISTANCE/MOISTURE CONTENT
0 10 20 30 40 50 = BLOWS PER FOOT
= MOISTURE CONTENT
2 of 2
0
2.5
5
7.5
10
12.5
15
17.5
TOPSOIL: Sandy Lean CLAY, appears soft, dark
brown, moist
Sandy Lean CLAY, soft, dark brown to brown, moist,
some sand, roots to about 6.0 feet
qu = 1.0 - 1.5 tsf
Clayey GRAVEL with Sand, medium dense to very
dense, brown, moist to wet
0.5
7.9
2-1-2
2-2-3
6-8-6
6-41-17
50/3"
58
50/3"
LEGEND LOG OF SOIL BORING B-2SPT blows per foot Atterberg Limits
Field Moisture content North Central Development
Bozeman, MontanaGroundwater Level
Grab/composite sample
1-3/8-inch I.D. split spoon Logged by:Craig Nadeau, PE
2-1/2-inch I.D. split spoon Drilled by:O'Keefe Drilling
Truck-mounted Mobile B-61 with 8-inch HSA2-1/2-inch I.D. ring sampler GNP = Granular and Nonplastic
3-inch I.D. thin-walled sampler Note: The stratification lines represent approximate
boundaries between soil types. Actual boundaries
may be gradual or transitional.
May 21-22, 2019 B20-068-001
No sample recovery Figure No. 3
Sheet
GR
A
P
H
I
C
LO
G
SOIL DESCRIPTION
SURFACE:Irrigated Lawn
SURFACE ELEVATION:4,796.5 feet
DE
P
T
H
(
F
T
)
GR
O
U
N
D
WA
T
E
R
SP
T
B
L
O
W
CO
U
N
T
S
SA
M
P
L
E
DE
P
T
H
(
F
T
)
PENETRATION RESISTANCE/MOISTURE CONTENT
0 10 20 30 40 50 = BLOWS PER FOOT
= MOISTURE CONTENT
1 of 2
20
22.5
25
27.5
30
32.5
35
Bottom of Boring - Piezometer Installed
30.5
9-26-50
22-50/
2"
50/5"
76
50/2"
50/5"
LEGEND LOG OF SOIL BORING B-2SPT blows per foot Atterberg Limits
Field Moisture content North Central Development
Bozeman, MontanaGroundwater Level
Grab/composite sample
1-3/8-inch I.D. split spoon Logged by:Craig Nadeau, PE
2-1/2-inch I.D. split spoon Drilled by:O'Keefe Drilling
Truck-mounted Mobile B-61 with 8-inch HSA2-1/2-inch I.D. ring sampler GNP = Granular and Nonplastic
3-inch I.D. thin-walled sampler Note: The stratification lines represent approximate
boundaries between soil types. Actual boundaries
may be gradual or transitional.
May 21-22, 2019 B20-068-001
No sample recovery Figure No. 3
Sheet
GR
A
P
H
I
C
LO
G
SOIL DESCRIPTION
SURFACE:Irrigated Lawn
SURFACE ELEVATION:4,796.5 feet
DE
P
T
H
(
F
T
)
GR
O
U
N
D
WA
T
E
R
SP
T
B
L
O
W
CO
U
N
T
S
SA
M
P
L
E
DE
P
T
H
(
F
T
)
PENETRATION RESISTANCE/MOISTURE CONTENT
0 10 20 30 40 50 = BLOWS PER FOOT
= MOISTURE CONTENT
2 of 2
0
2.5
5
7.5
10
12.5
15
17.5
TOPSOIL: Sandy Lean CLAY, appears soft, dark
brown, moist
Sandy Lean CLAY, very soft to firm, dark brown to
brown, moist
qu = 1.0 - 1.5 tsf
Clayey GRAVEL with Sand, medium dense to very
dense, brown, moist to wet
0.5
9.5
1-1-1
3-3-3
1-1-6
10-11-
13
12-17-
20
LEGEND LOG OF SOIL BORING B-3SPT blows per foot Atterberg Limits
Field Moisture content North Central Development
Bozeman, MontanaGroundwater Level
Grab/composite sample
1-3/8-inch I.D. split spoon Logged by:Craig Nadeau, PE
2-1/2-inch I.D. split spoon Drilled by:O'Keefe Drilling
Truck-mounted Mobile B-61 with 8-inch HSA2-1/2-inch I.D. ring sampler GNP = Granular and Nonplastic
3-inch I.D. thin-walled sampler Note: The stratification lines represent approximate
boundaries between soil types. Actual boundaries
may be gradual or transitional.
May 21, 2019 B20-068-001
No sample recovery Figure No. 4
Sheet
GR
A
P
H
I
C
LO
G
SOIL DESCRIPTION
SURFACE:Irrigated Lawn
SURFACE ELEVATION:4,799.9 feet
DE
P
T
H
(
F
T
)
GR
O
U
N
D
WA
T
E
R
SP
T
B
L
O
W
CO
U
N
T
S
SA
M
P
L
E
DE
P
T
H
(
F
T
)
PENETRATION RESISTANCE/MOISTURE CONTENT
0 10 20 30 40 50 = BLOWS PER FOOT
= MOISTURE CONTENT
1 of 2
20
22.5
25
27.5
30
32.5
35
Bottom of Boring - Piezometer Installed
Clayey SAND, medium dense, brown, wet
30.8
31.2
10-15-9
37-42-
47
24-10-
13
89
LEGEND LOG OF SOIL BORING B-3SPT blows per foot Atterberg Limits
Field Moisture content North Central Development
Bozeman, MontanaGroundwater Level
Grab/composite sample
1-3/8-inch I.D. split spoon Logged by:Craig Nadeau, PE
2-1/2-inch I.D. split spoon Drilled by:O'Keefe Drilling
Truck-mounted Mobile B-61 with 8-inch HSA2-1/2-inch I.D. ring sampler GNP = Granular and Nonplastic
3-inch I.D. thin-walled sampler Note: The stratification lines represent approximate
boundaries between soil types. Actual boundaries
may be gradual or transitional.
May 21, 2019 B20-068-001
No sample recovery Figure No. 4
Sheet
GR
A
P
H
I
C
LO
G
SOIL DESCRIPTION
SURFACE:Irrigated Lawn
SURFACE ELEVATION:4,799.9 feet
DE
P
T
H
(
F
T
)
GR
O
U
N
D
WA
T
E
R
SP
T
B
L
O
W
CO
U
N
T
S
SA
M
P
L
E
DE
P
T
H
(
F
T
)
PENETRATION RESISTANCE/MOISTURE CONTENT
0 10 20 30 40 50 = BLOWS PER FOOT
= MOISTURE CONTENT
2 of 2
0
2.5
5
7.5
10
12.5
15
17.5
TOPSOIL: Sandy Lean CLAY, appears soft, dark
brown, moist
Sandy Lean CLAY, soft to firm, dark brown to brown,
moist
Clayey GRAVEL with Sand, dense to very dense,
brown, moist to wet
0.5
7.0
2-3-4
2-2-1
17-17-
27
17-47-
18
50/5"
65
50/5"
LEGEND LOG OF SOIL BORING B-4SPT blows per foot Atterberg Limits
Field Moisture content North Central Development
Bozeman, MontanaGroundwater Level
Grab/composite sample
1-3/8-inch I.D. split spoon Logged by:Craig Nadeau, PE
2-1/2-inch I.D. split spoon Drilled by:O'Keefe Drilling
Truck-mounted Mobile B-61 with 8-inch HSA2-1/2-inch I.D. ring sampler GNP = Granular and Nonplastic
3-inch I.D. thin-walled sampler Note: The stratification lines represent approximate
boundaries between soil types. Actual boundaries
may be gradual or transitional.
May 21, 2019 B20-068-001
No sample recovery Figure No. 5
Sheet
GR
A
P
H
I
C
LO
G
SOIL DESCRIPTION
SURFACE:Irrigated Lawn
SURFACE ELEVATION:4,802.1 feet
DE
P
T
H
(
F
T
)
GR
O
U
N
D
WA
T
E
R
SP
T
B
L
O
W
CO
U
N
T
S
SA
M
P
L
E
DE
P
T
H
(
F
T
)
PENETRATION RESISTANCE/MOISTURE CONTENT
0 10 20 30 40 50 = BLOWS PER FOOT
= MOISTURE CONTENT
1 of 2
20
22.5
25
27.5
30
32.5
35
- Clayey SAND lense from 20.0 to 21.0 feet
Bottom of Boring - Piezometer Installed
30.5
6-7-43
16-28-
35
50/5"
63
50/5"
LEGEND LOG OF SOIL BORING B-4SPT blows per foot Atterberg Limits
Field Moisture content North Central Development
Bozeman, MontanaGroundwater Level
Grab/composite sample
1-3/8-inch I.D. split spoon Logged by:Craig Nadeau, PE
2-1/2-inch I.D. split spoon Drilled by:O'Keefe Drilling
Truck-mounted Mobile B-61 with 8-inch HSA2-1/2-inch I.D. ring sampler GNP = Granular and Nonplastic
3-inch I.D. thin-walled sampler Note: The stratification lines represent approximate
boundaries between soil types. Actual boundaries
may be gradual or transitional.
May 21, 2019 B20-068-001
No sample recovery Figure No. 5
Sheet
GR
A
P
H
I
C
LO
G
SOIL DESCRIPTION
SURFACE:Irrigated Lawn
SURFACE ELEVATION:4,802.1 feet
DE
P
T
H
(
F
T
)
GR
O
U
N
D
WA
T
E
R
SP
T
B
L
O
W
CO
U
N
T
S
SA
M
P
L
E
DE
P
T
H
(
F
T
)
PENETRATION RESISTANCE/MOISTURE CONTENT
0 10 20 30 40 50 = BLOWS PER FOOT
= MOISTURE CONTENT
2 of 2
0
2.5
5
7.5
10
12.5
15
17.5
Asphalt Pavement
Poorly-Graded GRAVEL with Sand (Base Course),
relatively dense, brown, slightly moist
Sandy Lean CLAY, very soft, brown to dark brown,
moist
qu = 1.0 tsf
- See Figures 46 and 48 for Unconfined Compression
and Consolidation Test Results
Clayeye GRAVEL with Sand, medium dense to very
dense, brown, slightly moist to wet
0.3
2.0
7.9
2-1-1
PUSH
3-6-14
23-21-
22
40-12-
13
T
LEGEND LOG OF SOIL BORING B-5SPT blows per foot Atterberg Limits
Field Moisture content North Central Development
Bozeman, MontanaGroundwater Level
Grab/composite sample
1-3/8-inch I.D. split spoon Logged by:Craig Nadeau, PE
2-1/2-inch I.D. split spoon Drilled by:O'Keefe Drilling
Truck-mounted Mobile B-61 with 8-inch HSA2-1/2-inch I.D. ring sampler GNP = Granular and Nonplastic
3-inch I.D. thin-walled sampler Note: The stratification lines represent approximate
boundaries between soil types. Actual boundaries
may be gradual or transitional.
September 15, 2020 B20-068-001
No sample recovery Figure No. 6
Sheet
GR
A
P
H
I
C
LO
G
SOIL DESCRIPTION
SURFACE:Asphalt Parking Lot
SURFACE ELEVATION:4,799.9 feet
DE
P
T
H
(
F
T
)
GR
O
U
N
D
WA
T
E
R
SP
T
B
L
O
W
CO
U
N
T
S
SA
M
P
L
E
DE
P
T
H
(
F
T
)
PENETRATION RESISTANCE/MOISTURE CONTENT
0 10 20 30 40 50 = BLOWS PER FOOT
= MOISTURE CONTENT
1 of 2
20
22.5
25
27.5
30
32.5
35
- 6" of heaved sand in augers prior to sampling
Bottom of Boring
31.3
50/2.5"
50/4"
11-24-
50/3"
50/2.5"
50/4"
74/9"
LEGEND LOG OF SOIL BORING B-5SPT blows per foot Atterberg Limits
Field Moisture content North Central Development
Bozeman, MontanaGroundwater Level
Grab/composite sample
1-3/8-inch I.D. split spoon Logged by:Craig Nadeau, PE
2-1/2-inch I.D. split spoon Drilled by:O'Keefe Drilling
Truck-mounted Mobile B-61 with 8-inch HSA2-1/2-inch I.D. ring sampler GNP = Granular and Nonplastic
3-inch I.D. thin-walled sampler Note: The stratification lines represent approximate
boundaries between soil types. Actual boundaries
may be gradual or transitional.
September 15, 2020 B20-068-001
No sample recovery Figure No. 6
Sheet
GR
A
P
H
I
C
LO
G
SOIL DESCRIPTION
SURFACE:Asphalt Parking Lot
SURFACE ELEVATION:4,799.9 feet
DE
P
T
H
(
F
T
)
GR
O
U
N
D
WA
T
E
R
SP
T
B
L
O
W
CO
U
N
T
S
SA
M
P
L
E
DE
P
T
H
(
F
T
)
PENETRATION RESISTANCE/MOISTURE CONTENT
0 10 20 30 40 50 = BLOWS PER FOOT
= MOISTURE CONTENT
2 of 2
0
2.5
5
7.5
10
12.5
15
17.5
TOPSOIL: Sandy Lean CLAY, appears soft to firm,
dark brown, moist
Sandy Lean CLAY, appears firm to stiff, dark brown
moist, scattered gravels
- See Figures 53 and 54 for Proctor and CBR Test
Results
Clayey GRAVEL with Sand, dense to very dense,
grayish brown, slightly moist to wet, up to 4" cobbles
observed
0.5
4.0
4-6-10
BULK
13-18-
21
17-27-
20
13-26-
23
13-13-
24
G
LEGEND LOG OF SOIL BORING B-6SPT blows per foot Atterberg Limits
Field Moisture content North Central Development
Bozeman, MontanaGroundwater Level
Grab/composite sample
1-3/8-inch I.D. split spoon Logged by:Craig Nadeau, PE
2-1/2-inch I.D. split spoon Drilled by:O'Keefe Drilling
Truck-mounted Mobile B-61 with 8-inch HSA2-1/2-inch I.D. ring sampler GNP = Granular and Nonplastic
3-inch I.D. thin-walled sampler Note: The stratification lines represent approximate
boundaries between soil types. Actual boundaries
may be gradual or transitional.
September 15, 2020 B20-068-001
No sample recovery Figure No. 7
Sheet
GR
A
P
H
I
C
LO
G
SOIL DESCRIPTION
SURFACE:Irrigated Sod
SURFACE ELEVATION:4,798.4 feet
DE
P
T
H
(
F
T
)
GR
O
U
N
D
WA
T
E
R
SP
T
B
L
O
W
CO
U
N
T
S
SA
M
P
L
E
DE
P
T
H
(
F
T
)
PENETRATION RESISTANCE/MOISTURE CONTENT
0 10 20 30 40 50 = BLOWS PER FOOT
= MOISTURE CONTENT
1 of 2
20
22.5
25
27.5
30
32.5
35
Bottom of Boring
31.4
13-16-
23
22-50/
5"
14-32-
50/4"
50/5"
82/10"
LEGEND LOG OF SOIL BORING B-6SPT blows per foot Atterberg Limits
Field Moisture content North Central Development
Bozeman, MontanaGroundwater Level
Grab/composite sample
1-3/8-inch I.D. split spoon Logged by:Craig Nadeau, PE
2-1/2-inch I.D. split spoon Drilled by:O'Keefe Drilling
Truck-mounted Mobile B-61 with 8-inch HSA2-1/2-inch I.D. ring sampler GNP = Granular and Nonplastic
3-inch I.D. thin-walled sampler Note: The stratification lines represent approximate
boundaries between soil types. Actual boundaries
may be gradual or transitional.
September 15, 2020 B20-068-001
No sample recovery Figure No. 7
Sheet
GR
A
P
H
I
C
LO
G
SOIL DESCRIPTION
SURFACE:Irrigated Sod
SURFACE ELEVATION:4,798.4 feet
DE
P
T
H
(
F
T
)
GR
O
U
N
D
WA
T
E
R
SP
T
B
L
O
W
CO
U
N
T
S
SA
M
P
L
E
DE
P
T
H
(
F
T
)
PENETRATION RESISTANCE/MOISTURE CONTENT
0 10 20 30 40 50 = BLOWS PER FOOT
= MOISTURE CONTENT
2 of 2
0
2.5
5
7.5
10
12.5
15
17.5
Asphalt Pavement
Poorly-Graded GRAVEL with Sand, relatively dense,
brown, moist
Sandy Lean CLAY, soft, brown, moist
qu = 1.5 tsf
- See Figure 49 for Consolidation Test Result
Clayey GRAVEL with Sand, dense to very dense,
brown, moist to wet
0.3
2.0
6.0
4-2-2
PUSH
15-20-
47
42-50/
2"
BULK
13-21-
14
T
G
67
50/2"
LEGEND LOG OF SOIL BORING B-7SPT blows per foot Atterberg Limits
Field Moisture content North Central Development
Bozeman, MontanaGroundwater Level
Grab/composite sample
1-3/8-inch I.D. split spoon Logged by:Craig Nadeau, PE
2-1/2-inch I.D. split spoon Drilled by:O'Keefe Drilling
Truck-mounted Mobile B-61 with 8-inch HSA2-1/2-inch I.D. ring sampler GNP = Granular and Nonplastic
3-inch I.D. thin-walled sampler Note: The stratification lines represent approximate
boundaries between soil types. Actual boundaries
may be gradual or transitional.
September 15, 2020 B20-068-001
No sample recovery Figure No. 8
Sheet
GR
A
P
H
I
C
LO
G
SOIL DESCRIPTION
SURFACE:Asphalt Parking Lot
SURFACE ELEVATION:4,801.2 feet
DE
P
T
H
(
F
T
)
GR
O
U
N
D
WA
T
E
R
SP
T
B
L
O
W
CO
U
N
T
S
SA
M
P
L
E
DE
P
T
H
(
F
T
)
PENETRATION RESISTANCE/MOISTURE CONTENT
0 10 20 30 40 50 = BLOWS PER FOOT
= MOISTURE CONTENT
1 of 2
20
22.5
25
27.5
30
32.5
35
Bottom of Boring
31.5
19-22-
36
22-50/
5"
36-45-
47
58
50/5"
92
LEGEND LOG OF SOIL BORING B-7SPT blows per foot Atterberg Limits
Field Moisture content North Central Development
Bozeman, MontanaGroundwater Level
Grab/composite sample
1-3/8-inch I.D. split spoon Logged by:Craig Nadeau, PE
2-1/2-inch I.D. split spoon Drilled by:O'Keefe Drilling
Truck-mounted Mobile B-61 with 8-inch HSA2-1/2-inch I.D. ring sampler GNP = Granular and Nonplastic
3-inch I.D. thin-walled sampler Note: The stratification lines represent approximate
boundaries between soil types. Actual boundaries
may be gradual or transitional.
September 15, 2020 B20-068-001
No sample recovery Figure No. 8
Sheet
GR
A
P
H
I
C
LO
G
SOIL DESCRIPTION
SURFACE:Asphalt Parking Lot
SURFACE ELEVATION:4,801.2 feet
DE
P
T
H
(
F
T
)
GR
O
U
N
D
WA
T
E
R
SP
T
B
L
O
W
CO
U
N
T
S
SA
M
P
L
E
DE
P
T
H
(
F
T
)
PENETRATION RESISTANCE/MOISTURE CONTENT
0 10 20 30 40 50 = BLOWS PER FOOT
= MOISTURE CONTENT
2 of 2
0
2.5
5
7.5
10
12.5
15
17.5
Asphalt Pavement
Poorly-Graded GRAVEL with Sand, relatively dense,
brown, moist
Lean CLAY with Sand, soft to firm, light brown, moist
Clayey GRAVEL with Sand, dense to very dense,
brown, moist to wet
0.2
2.0
6.5
3-3-2
3-3-3
20-30-
36
25-50/
3"
15-30-
31
66
50/3"
61
LEGEND LOG OF SOIL BORING B-8SPT blows per foot Atterberg Limits
Field Moisture content North Central Development
Bozeman, MontanaGroundwater Level
Grab/composite sample
1-3/8-inch I.D. split spoon Logged by:Craig Nadeau, PE
2-1/2-inch I.D. split spoon Drilled by:O'Keefe Drilling
Truck-mounted Mobile B-61 with 8-inch HSA2-1/2-inch I.D. ring sampler GNP = Granular and Nonplastic
3-inch I.D. thin-walled sampler Note: The stratification lines represent approximate
boundaries between soil types. Actual boundaries
may be gradual or transitional.
September 15, 2020 B20-068-001
No sample recovery Figure No. 9
Sheet
GR
A
P
H
I
C
LO
G
SOIL DESCRIPTION
SURFACE:Asphalt Parking Lot
SURFACE ELEVATION:4,802.0 feet
DE
P
T
H
(
F
T
)
GR
O
U
N
D
WA
T
E
R
SP
T
B
L
O
W
CO
U
N
T
S
SA
M
P
L
E
DE
P
T
H
(
F
T
)
PENETRATION RESISTANCE/MOISTURE CONTENT
0 10 20 30 40 50 = BLOWS PER FOOT
= MOISTURE CONTENT
1 of 2
20
22.5
25
27.5
30
32.5
35
Bottom of Boring
31.0
27-38-
50/4"
10-14-
18
36-50/
5"
88/10"
50/5"
LEGEND LOG OF SOIL BORING B-8SPT blows per foot Atterberg Limits
Field Moisture content North Central Development
Bozeman, MontanaGroundwater Level
Grab/composite sample
1-3/8-inch I.D. split spoon Logged by:Craig Nadeau, PE
2-1/2-inch I.D. split spoon Drilled by:O'Keefe Drilling
Truck-mounted Mobile B-61 with 8-inch HSA2-1/2-inch I.D. ring sampler GNP = Granular and Nonplastic
3-inch I.D. thin-walled sampler Note: The stratification lines represent approximate
boundaries between soil types. Actual boundaries
may be gradual or transitional.
September 15, 2020 B20-068-001
No sample recovery Figure No. 9
Sheet
GR
A
P
H
I
C
LO
G
SOIL DESCRIPTION
SURFACE:Asphalt Parking Lot
SURFACE ELEVATION:4,802.0 feet
DE
P
T
H
(
F
T
)
GR
O
U
N
D
WA
T
E
R
SP
T
B
L
O
W
CO
U
N
T
S
SA
M
P
L
E
DE
P
T
H
(
F
T
)
PENETRATION RESISTANCE/MOISTURE CONTENT
0 10 20 30 40 50 = BLOWS PER FOOT
= MOISTURE CONTENT
2 of 2
0
2.5
5
7.5
10
12.5
15
17.5
Asphalt Pavement
Poorly-Graded GRAVEL with Sand, relatively dense,
brown, moist
Sandy Lean CLAY, firm to stiff, grayish brown, moist
- See Figures 47 and 50 for Unconfined Compression
and Consolidation Test Results
Clayey SAND with Gravel, loose, brown, slightly
moist
Clayey GRAVEL with Sand, dense to very dense,
grayish brown, moist to wet
0.5
2.5
6.0
9.0
2-4-5
PUSH
3-4-4
16-29-
25
20-13-
16
T
54
LEGEND LOG OF SOIL BORING B-9SPT blows per foot Atterberg Limits
Field Moisture content North Central Development
Bozeman, MontanaGroundwater Level
Grab/composite sample
1-3/8-inch I.D. split spoon Logged by:Craig Nadeau, PE
2-1/2-inch I.D. split spoon Drilled by:O'Keefe Drilling
Truck-mounted Mobile B-61 with 8-inch HSA2-1/2-inch I.D. ring sampler GNP = Granular and Nonplastic
3-inch I.D. thin-walled sampler Note: The stratification lines represent approximate
boundaries between soil types. Actual boundaries
may be gradual or transitional.
September 16, 2020 B20-068-001
No sample recovery Figure No. 10
Sheet
GR
A
P
H
I
C
LO
G
SOIL DESCRIPTION
SURFACE:Asphalt Parking Lot
SURFACE ELEVATION:4,797.5 feet
DE
P
T
H
(
F
T
)
GR
O
U
N
D
WA
T
E
R
SP
T
B
L
O
W
CO
U
N
T
S
SA
M
P
L
E
DE
P
T
H
(
F
T
)
PENETRATION RESISTANCE/MOISTURE CONTENT
0 10 20 30 40 50 = BLOWS PER FOOT
= MOISTURE CONTENT
1 of 2
20
22.5
25
27.5
30
32.5
35
- Zone of medium dense clayey sand from
approximately 25 to 26 feet
Bottom of Boring
30.8
7-15-26
9-17-37
32-50/
4"
54
50/4"
LEGEND LOG OF SOIL BORING B-9SPT blows per foot Atterberg Limits
Field Moisture content North Central Development
Bozeman, MontanaGroundwater Level
Grab/composite sample
1-3/8-inch I.D. split spoon Logged by:Craig Nadeau, PE
2-1/2-inch I.D. split spoon Drilled by:O'Keefe Drilling
Truck-mounted Mobile B-61 with 8-inch HSA2-1/2-inch I.D. ring sampler GNP = Granular and Nonplastic
3-inch I.D. thin-walled sampler Note: The stratification lines represent approximate
boundaries between soil types. Actual boundaries
may be gradual or transitional.
September 16, 2020 B20-068-001
No sample recovery Figure No. 10
Sheet
GR
A
P
H
I
C
LO
G
SOIL DESCRIPTION
SURFACE:Asphalt Parking Lot
SURFACE ELEVATION:4,797.5 feet
DE
P
T
H
(
F
T
)
GR
O
U
N
D
WA
T
E
R
SP
T
B
L
O
W
CO
U
N
T
S
SA
M
P
L
E
DE
P
T
H
(
F
T
)
PENETRATION RESISTANCE/MOISTURE CONTENT
0 10 20 30 40 50 = BLOWS PER FOOT
= MOISTURE CONTENT
2 of 2
0
2.5
5
7.5
10
12.5
15
17.5
Asphalt Pavement
Poorly-Graded GRAVEL with Sand, relatively dense,
brown, moist
FILL: Lean CLAY with Sand, firm, dark brown, moist,
some gravel, brick and wood fragments
- See Figures 53 and 54 for Proctor and CBR Test
Results
FILL: Clayey SAND with Gravel, dense, gray and
brown, slightly moist, suspected concrete debris
Lean CLAY with Sand, firm, brown, moist
- Pushed rock with tip of spoon
qu = 1.0 - 2.0 tsf
Clayey GRAVEL with Sand, dense to very dense,
brown, moist to wet
0.3
1.5
3.3
6.6
12.0
3-24-33
BULK
12-50/
6"
2-2-3
2-2-3
18-14-
16
G
57
50/6"
LEGEND LOG OF SOIL BORING B-10SPT blows per foot Atterberg Limits
Field Moisture content North Central Development
Bozeman, MontanaGroundwater Level
Grab/composite sample
1-3/8-inch I.D. split spoon Logged by:Craig Nadeau, PE
2-1/2-inch I.D. split spoon Drilled by:O'Keefe Drilling
Truck-mounted Mobile B-61 with 8-inch HSA2-1/2-inch I.D. ring sampler GNP = Granular and Nonplastic
3-inch I.D. thin-walled sampler Note: The stratification lines represent approximate
boundaries between soil types. Actual boundaries
may be gradual or transitional.
September 16, 2020 B20-068-001
No sample recovery Figure No. 11
Sheet
GR
A
P
H
I
C
LO
G
SOIL DESCRIPTION
SURFACE:Asphalt Parking Lot
SURFACE ELEVATION:4,801.5 feet
DE
P
T
H
(
F
T
)
GR
O
U
N
D
WA
T
E
R
SP
T
B
L
O
W
CO
U
N
T
S
SA
M
P
L
E
DE
P
T
H
(
F
T
)
PENETRATION RESISTANCE/MOISTURE CONTENT
0 10 20 30 40 50 = BLOWS PER FOOT
= MOISTURE CONTENT
1 of 2
20
22.5
25
27.5
30
32.5
35
- Stiff clay seam from 27 to 28 feet
Bottom of Boring
31.5
20-20-
30
32-50/
4"
13-26-
34
50/4"
60
LEGEND LOG OF SOIL BORING B-10SPT blows per foot Atterberg Limits
Field Moisture content North Central Development
Bozeman, MontanaGroundwater Level
Grab/composite sample
1-3/8-inch I.D. split spoon Logged by:Craig Nadeau, PE
2-1/2-inch I.D. split spoon Drilled by:O'Keefe Drilling
Truck-mounted Mobile B-61 with 8-inch HSA2-1/2-inch I.D. ring sampler GNP = Granular and Nonplastic
3-inch I.D. thin-walled sampler Note: The stratification lines represent approximate
boundaries between soil types. Actual boundaries
may be gradual or transitional.
September 16, 2020 B20-068-001
No sample recovery Figure No. 11
Sheet
GR
A
P
H
I
C
LO
G
SOIL DESCRIPTION
SURFACE:Asphalt Parking Lot
SURFACE ELEVATION:4,801.5 feet
DE
P
T
H
(
F
T
)
GR
O
U
N
D
WA
T
E
R
SP
T
B
L
O
W
CO
U
N
T
S
SA
M
P
L
E
DE
P
T
H
(
F
T
)
PENETRATION RESISTANCE/MOISTURE CONTENT
0 10 20 30 40 50 = BLOWS PER FOOT
= MOISTURE CONTENT
2 of 2
0
2.5
5
7.5
10
12.5
15
17.5
TOPSOIL: Lean CLAY with Sand, appears firm,
brown, slightly moist, scattered gravels
Sandy SILT, firm to stiff, brown, slightly moist,
scattered gravels
Clayey GRAVEL with Sand, medium dense to very
dense, brown, slightly moist to wet
0.5
7.0
3-4-5
4-3-3
6-6-8
10-12-
16
19-50/
1"50/1"
LEGEND LOG OF SOIL BORING B-11SPT blows per foot Atterberg Limits
Field Moisture content North Central Development
Bozeman, MontanaGroundwater Level
Grab/composite sample
1-3/8-inch I.D. split spoon Logged by:Craig Nadeau, PE
2-1/2-inch I.D. split spoon Drilled by:O'Keefe Drilling
Truck-mounted Mobile B-61 with 8-inch HSA2-1/2-inch I.D. ring sampler GNP = Granular and Nonplastic
3-inch I.D. thin-walled sampler Note: The stratification lines represent approximate
boundaries between soil types. Actual boundaries
may be gradual or transitional.
September 16, 2020 B20-068-001
No sample recovery Figure No. 12
Sheet
GR
A
P
H
I
C
LO
G
SOIL DESCRIPTION
SURFACE:Boulevard Sod
SURFACE ELEVATION:4,805.9 feet
DE
P
T
H
(
F
T
)
GR
O
U
N
D
WA
T
E
R
SP
T
B
L
O
W
CO
U
N
T
S
SA
M
P
L
E
DE
P
T
H
(
F
T
)
PENETRATION RESISTANCE/MOISTURE CONTENT
0 10 20 30 40 50 = BLOWS PER FOOT
= MOISTURE CONTENT
1 of 2
20
22.5
25
27.5
30
32.5
35
Bottom of Boring
31.8
26-33-
50
27-50/
6"
25-42-
50/4"
83
50/6"
92/10"
LEGEND LOG OF SOIL BORING B-11SPT blows per foot Atterberg Limits
Field Moisture content North Central Development
Bozeman, MontanaGroundwater Level
Grab/composite sample
1-3/8-inch I.D. split spoon Logged by:Craig Nadeau, PE
2-1/2-inch I.D. split spoon Drilled by:O'Keefe Drilling
Truck-mounted Mobile B-61 with 8-inch HSA2-1/2-inch I.D. ring sampler GNP = Granular and Nonplastic
3-inch I.D. thin-walled sampler Note: The stratification lines represent approximate
boundaries between soil types. Actual boundaries
may be gradual or transitional.
September 16, 2020 B20-068-001
No sample recovery Figure No. 12
Sheet
GR
A
P
H
I
C
LO
G
SOIL DESCRIPTION
SURFACE:Boulevard Sod
SURFACE ELEVATION:4,805.9 feet
DE
P
T
H
(
F
T
)
GR
O
U
N
D
WA
T
E
R
SP
T
B
L
O
W
CO
U
N
T
S
SA
M
P
L
E
DE
P
T
H
(
F
T
)
PENETRATION RESISTANCE/MOISTURE CONTENT
0 10 20 30 40 50 = BLOWS PER FOOT
= MOISTURE CONTENT
2 of 2
0
2.5
5
7.5
10
12.5
15
17.5
Asphalt Pavement
Poorly-Graded GRAVEL with Sand, relatively dense,
brown, slightly moist
Lean CLAY with Sand, soft to firm, dark gray, moist
- See Figure 51 for Consolidation Test Result
Clayey SAND, relatively loose, brown, moist
Clayey GRAVEL with Sand, dense to very dense,
brown, moist to wet
0.3
0.5
6.5
8.0
2-1-2
PUSH
2-3-13
10-14-
16
21-23-
19
T
LEGEND LOG OF SOIL BORING B-12SPT blows per foot Atterberg Limits
Field Moisture content North Central Development
Bozeman, MontanaGroundwater Level
Grab/composite sample
1-3/8-inch I.D. split spoon Logged by:Craig Nadeau, PE
2-1/2-inch I.D. split spoon Drilled by:O'Keefe Drilling
Truck-mounted Mobile B-61 with 8-inch HSA2-1/2-inch I.D. ring sampler GNP = Granular and Nonplastic
3-inch I.D. thin-walled sampler Note: The stratification lines represent approximate
boundaries between soil types. Actual boundaries
may be gradual or transitional.
September 16, 2020 B20-068-001
No sample recovery Figure No. 13
Sheet
GR
A
P
H
I
C
LO
G
SOIL DESCRIPTION
SURFACE:Asphalt Parking Lot
SURFACE ELEVATION:4,801.4 feet
DE
P
T
H
(
F
T
)
GR
O
U
N
D
WA
T
E
R
SP
T
B
L
O
W
CO
U
N
T
S
SA
M
P
L
E
DE
P
T
H
(
F
T
)
PENETRATION RESISTANCE/MOISTURE CONTENT
0 10 20 30 40 50 = BLOWS PER FOOT
= MOISTURE CONTENT
1 of 2
20
22.5
25
27.5
30
32.5
35
Bottom of Boring
31.1
50/6"
43-42-
54
27-36-
50/1"
50/6"
96
86/7"
LEGEND LOG OF SOIL BORING B-12SPT blows per foot Atterberg Limits
Field Moisture content North Central Development
Bozeman, MontanaGroundwater Level
Grab/composite sample
1-3/8-inch I.D. split spoon Logged by:Craig Nadeau, PE
2-1/2-inch I.D. split spoon Drilled by:O'Keefe Drilling
Truck-mounted Mobile B-61 with 8-inch HSA2-1/2-inch I.D. ring sampler GNP = Granular and Nonplastic
3-inch I.D. thin-walled sampler Note: The stratification lines represent approximate
boundaries between soil types. Actual boundaries
may be gradual or transitional.
September 16, 2020 B20-068-001
No sample recovery Figure No. 13
Sheet
GR
A
P
H
I
C
LO
G
SOIL DESCRIPTION
SURFACE:Asphalt Parking Lot
SURFACE ELEVATION:4,801.4 feet
DE
P
T
H
(
F
T
)
GR
O
U
N
D
WA
T
E
R
SP
T
B
L
O
W
CO
U
N
T
S
SA
M
P
L
E
DE
P
T
H
(
F
T
)
PENETRATION RESISTANCE/MOISTURE CONTENT
0 10 20 30 40 50 = BLOWS PER FOOT
= MOISTURE CONTENT
2 of 2
0
2.5
5
7.5
10
12.5
15
17.5
TOPSOIL: Lean CLAY with Sand, appears firm,
brown, slightly moist
Sandy Lean CLAY, firm, brown, slightly moist
Clayey GRAVEL with Sand, medium dense to very
dense, brown, moist to wet
0.5
8.1
4-3-2
4-4-3
4-13-11
15-15-
10
20-20-
23
BULK
LEGEND LOG OF SOIL BORING B-13SPT blows per foot Atterberg Limits
Field Moisture content North Central Development
Bozeman, MontanaGroundwater Level
Grab/composite sample
1-3/8-inch I.D. split spoon Logged by:Craig Nadeau, PE
2-1/2-inch I.D. split spoon Drilled by:O'Keefe Drilling
Truck-mounted Mobile B-61 with 8-inch HSA2-1/2-inch I.D. ring sampler GNP = Granular and Nonplastic
3-inch I.D. thin-walled sampler Note: The stratification lines represent approximate
boundaries between soil types. Actual boundaries
may be gradual or transitional.
September 17, 2020 B20-068-001
No sample recovery Figure No. 14
Sheet
GR
A
P
H
I
C
LO
G
SOIL DESCRIPTION
SURFACE:Irrigated Sod
SURFACE ELEVATION:4,801.5 feet
DE
P
T
H
(
F
T
)
GR
O
U
N
D
WA
T
E
R
SP
T
B
L
O
W
CO
U
N
T
S
SA
M
P
L
E
DE
P
T
H
(
F
T
)
PENETRATION RESISTANCE/MOISTURE CONTENT
0 10 20 30 40 50 = BLOWS PER FOOT
= MOISTURE CONTENT
1 of 2
20
22.5
25
27.5
30
32.5
35
Bottom of Boring
31.5
50/6"
6-32-
50/5"
35-47-
25
G
50/6"
82/11"
72
LEGEND LOG OF SOIL BORING B-13SPT blows per foot Atterberg Limits
Field Moisture content North Central Development
Bozeman, MontanaGroundwater Level
Grab/composite sample
1-3/8-inch I.D. split spoon Logged by:Craig Nadeau, PE
2-1/2-inch I.D. split spoon Drilled by:O'Keefe Drilling
Truck-mounted Mobile B-61 with 8-inch HSA2-1/2-inch I.D. ring sampler GNP = Granular and Nonplastic
3-inch I.D. thin-walled sampler Note: The stratification lines represent approximate
boundaries between soil types. Actual boundaries
may be gradual or transitional.
September 17, 2020 B20-068-001
No sample recovery Figure No. 14
Sheet
GR
A
P
H
I
C
LO
G
SOIL DESCRIPTION
SURFACE:Irrigated Sod
SURFACE ELEVATION:4,801.5 feet
DE
P
T
H
(
F
T
)
GR
O
U
N
D
WA
T
E
R
SP
T
B
L
O
W
CO
U
N
T
S
SA
M
P
L
E
DE
P
T
H
(
F
T
)
PENETRATION RESISTANCE/MOISTURE CONTENT
0 10 20 30 40 50 = BLOWS PER FOOT
= MOISTURE CONTENT
2 of 2
0
2.5
5
7.5
10
12.5
15
17.5
TOPSOIL: Lean CLAY with Sand, appears firm,
brown, slightly moist
Sandy Lean CLAY, firm, brown, slightly moist
- Scattered gravels from 3.0 to 4.5 feet
- See Figure 52 for Consolidation Test Result
Clayey SAND, medium dense, grayish brown, slightly
moist, some gravel
Clayey GRAVEL with Sand, dense to very dense,
brown, moist to wet
0.5
7.0
9.0
2-11-9
PUSH
7-4-6
21-14-
24
14-25-
20
T
LEGEND LOG OF SOIL BORING B-14SPT blows per foot Atterberg Limits
Field Moisture content North Central Development
Bozeman, MontanaGroundwater Level
Grab/composite sample
1-3/8-inch I.D. split spoon Logged by:Craig Nadeau, PE
2-1/2-inch I.D. split spoon Drilled by:O'Keefe Drilling
Truck-mounted Mobile B-61 with 8-inch HSA2-1/2-inch I.D. ring sampler GNP = Granular and Nonplastic
3-inch I.D. thin-walled sampler Note: The stratification lines represent approximate
boundaries between soil types. Actual boundaries
may be gradual or transitional.
September 17, 2020 B20-068-001
No sample recovery Figure No. 15
Sheet
GR
A
P
H
I
C
LO
G
SOIL DESCRIPTION
SURFACE:Irrigated Sod
SURFACE ELEVATION:4,803.4 feet
DE
P
T
H
(
F
T
)
GR
O
U
N
D
WA
T
E
R
SP
T
B
L
O
W
CO
U
N
T
S
SA
M
P
L
E
DE
P
T
H
(
F
T
)
PENETRATION RESISTANCE/MOISTURE CONTENT
0 10 20 30 40 50 = BLOWS PER FOOT
= MOISTURE CONTENT
1 of 2
20
22.5
25
27.5
30
32.5
35
- Seam of sandy lean clay from approximately 19.5 to
20.5 feet
Bottom of Boring
31.2
4-17-26
16-31-
50/4"
10-24-
50/2"
81/10"
74/8"
LEGEND LOG OF SOIL BORING B-14SPT blows per foot Atterberg Limits
Field Moisture content North Central Development
Bozeman, MontanaGroundwater Level
Grab/composite sample
1-3/8-inch I.D. split spoon Logged by:Craig Nadeau, PE
2-1/2-inch I.D. split spoon Drilled by:O'Keefe Drilling
Truck-mounted Mobile B-61 with 8-inch HSA2-1/2-inch I.D. ring sampler GNP = Granular and Nonplastic
3-inch I.D. thin-walled sampler Note: The stratification lines represent approximate
boundaries between soil types. Actual boundaries
may be gradual or transitional.
September 17, 2020 B20-068-001
No sample recovery Figure No. 15
Sheet
GR
A
P
H
I
C
LO
G
SOIL DESCRIPTION
SURFACE:Irrigated Sod
SURFACE ELEVATION:4,803.4 feet
DE
P
T
H
(
F
T
)
GR
O
U
N
D
WA
T
E
R
SP
T
B
L
O
W
CO
U
N
T
S
SA
M
P
L
E
DE
P
T
H
(
F
T
)
PENETRATION RESISTANCE/MOISTURE CONTENT
0 10 20 30 40 50 = BLOWS PER FOOT
= MOISTURE CONTENT
2 of 2
Tested By: KR Checked By:
7-10-2019
16
(no specification provided)
PL= LL= PI=
D90= D85= D60=
D50= D30= D15=
D10= Cu= Cc=
USCS= AASHTO=
*
Clayey SAND with Gravel
1.5"
1"
3/4"
1/2"
3/8"
#4
#10
#20
#40
#60
#80
#100
#200
100.0
96.8
92.3
84.5
79.9
67.7
51.3
35.7
25.9
21.4
19.0
17.6
13.8
16.9188 13.0762 3.1588
1.8695 0.5906 0.0950
SC
Report No. A-19585-206
Homebase Partners
North Central Development
Bozeman, Montana
B20-068-001
Material Description
Atterberg Limits
Coefficients
Classification
Remarks
Location: B-1
Sample Number: A-19585 COMP Depth: 13.0 - 28.5 ft Date:
Client:
Project:
Project No: Figure
SIEVE PERCENT SPEC. *PASS?
SIZE FINER PERCENT (X=NO)
PE
R
C
E
N
T
F
I
N
E
R
0
10
20
30
40
50
60
70
80
90
100
GRAIN SIZE - mm.
0.0001 0.001 0.01 0.1 110 100
% +3" Coarse
% Gravel
Fine Coarse Medium
% Sand
Fine Silt
% Fines
Clay
0.0 7.7 24.6 16.4 25.4 12.1 13.8
6
i
n
.
3
i
n
.
2
i
n
.
1½
i
n
.
1
i
n
.
¾ i
n
.
½ i
n
.
3/
8
i
n
.
#4 #1
0
#2
0
#3
0
#4
0
#6
0
#1
0
0
#1
4
0
#2
0
0
Particle Size Distribution Report
Tested By: WJC Checked By:
7-10-2019
17
(no specification provided)
PL= LL= PI=
D90= D85= D60=
D50= D30= D15=
D10= Cu= Cc=
USCS= AASHTO=
*
Sandy Lean CLAY
3/4"
1/2"
3/8"
#4
#10
#20
#40
#60
#80
#100
#200
100.0
99.2
97.8
93.9
88.4
83.3
78.2
73.9
70.3
67.8
58.4
2.5701 1.1188 0.0846
Report No. A-19589-206
Homebase Partners
North Central Development
Bozeman, Montana
B20-068-001
Material Description
Atterberg Limits
Coefficients
Classification
Remarks
Location: B-2
Sample Number: A-19589 Depth: 2.5 - 4.0 ft Date:
Client:
Project:
Project No: Figure
SIEVE PERCENT SPEC. *PASS?
SIZE FINER PERCENT (X=NO)
PE
R
C
E
N
T
F
I
N
E
R
0
10
20
30
40
50
60
70
80
90
100
GRAIN SIZE - mm.
0.0001 0.001 0.01 0.1 110 100
% +3" Coarse
% Gravel
Fine Coarse Medium
% Sand
Fine Silt
% Fines
Clay
0.0 0.0 6.1 5.5 10.2 19.8 58.4
6
i
n
.
3
i
n
.
2
i
n
.
1½
i
n
.
1
i
n
.
¾ i
n
.
½ i
n
.
3/
8
i
n
.
#4 #1
0
#2
0
#3
0
#4
0
#6
0
#1
0
0
#1
4
0
#2
0
0
Particle Size Distribution Report
Tested By: JS Checked By:
7-12-2019
18
(no specification provided)
PL= LL= PI=
D90= D85= D60=
D50= D30= D15=
D10= Cu= Cc=
USCS= AASHTO=
*
Clayey SAND with Gravel
1.5"
1"
3/4"
1/2"
3/8"
#4
#10
#20
#40
#60
#80
#100
#200
100.0
96.4
89.7
80.1
76.3
65.6
55.1
45.9
37.4
31.6
28.1
26.1
20.6
19.2488 15.9171 3.1236
1.2292 0.2150
SC
Report No. A-19592-206 Composite
Homebase Partners
North Central Development
Bozeman, Montana
B20-068-001
Material Description
Atterberg Limits
Coefficients
Classification
Remarks
Location: B-2
Sample Number: A-19592 COMP Depth: 10.0 - 30.5 ft Date:
Client:
Project:
Project No: Figure
SIEVE PERCENT SPEC. *PASS?
SIZE FINER PERCENT (X=NO)
PE
R
C
E
N
T
F
I
N
E
R
0
10
20
30
40
50
60
70
80
90
100
GRAIN SIZE - mm.
0.0001 0.001 0.01 0.1 110 100
% +3" Coarse
% Gravel
Fine Coarse Medium
% Sand
Fine Silt
% Fines
Clay
0.0 10.3 24.1 10.5 17.7 16.8 20.6
6
i
n
.
3
i
n
.
2
i
n
.
1½
i
n
.
1
i
n
.
¾ i
n
.
½ i
n
.
3/
8
i
n
.
#4 #1
0
#2
0
#3
0
#4
0
#6
0
#1
0
0
#1
4
0
#2
0
0
Particle Size Distribution Report
Tested By: WJC Checked By:
7-10-2019
19
(no specification provided)
PL= LL= PI=
D90= D85= D60=
D50= D30= D15=
D10= Cu= Cc=
USCS= AASHTO=
*
Clayey SAND
3/4"
1/2"
3/8"
#4
#10
#20
#40
#60
#80
#100
#200
100.0
98.7
96.1
92.0
85.8
81.9
79.7
76.3
69.5
63.9
45.6
3.5408 1.7531 0.1316
0.0900
SC
Report No. A-19598-206
Homebase Partners
North Central Development
Bozeman, Montana
B20-068-001
Material Description
Atterberg Limits
Coefficients
Classification
Remarks
Location: B-3
Sample Number: A-19598 Depth: 5.0 - 6.5 ft Date:
Client:
Project:
Project No: Figure
SIEVE PERCENT SPEC. *PASS?
SIZE FINER PERCENT (X=NO)
PE
R
C
E
N
T
F
I
N
E
R
0
10
20
30
40
50
60
70
80
90
100
GRAIN SIZE - mm.
0.0001 0.001 0.01 0.1 110 100
% +3" Coarse
% Gravel
Fine Coarse Medium
% Sand
Fine Silt
% Fines
Clay
0.0 0.0 8.0 6.2 6.1 34.1 45.6
6
i
n
.
3
i
n
.
2
i
n
.
1½
i
n
.
1
i
n
.
¾ i
n
.
½ i
n
.
3/
8
i
n
.
#4 #1
0
#2
0
#3
0
#4
0
#6
0
#1
0
0
#1
4
0
#2
0
0
Particle Size Distribution Report
Tested By: WJC Checked By:
7-10-2019
20
(no specification provided)
PL= LL= PI=
D90= D85= D60=
D50= D30= D15=
D10= Cu= Cc=
USCS= AASHTO=
*
Clayey SAND with Gravel
1.5"
1"
3/4"
1/2"
3/8"
#4
#10
#20
#40
#60
#80
#100
#200
100.0
97.2
91.9
82.9
79.2
67.0
55.5
45.8
37.4
31.7
27.9
25.9
20.2
17.5669 14.1455 2.9500
1.2177 0.2152
SC
Report No. A-19601-206
Homebase Partners
North Central Development
Bozeman, Montana
B20-068-001
Material Description
Atterberg Limits
Coefficients
Classification
Remarks
Location: B-3
Sample Number: A-19601 COMP Depth: 15.0 - 30.8 ft Date:
Client:
Project:
Project No: Figure
SIEVE PERCENT SPEC. *PASS?
SIZE FINER PERCENT (X=NO)
PE
R
C
E
N
T
F
I
N
E
R
0
10
20
30
40
50
60
70
80
90
100
GRAIN SIZE - mm.
0.0001 0.001 0.01 0.1 110 100
% +3" Coarse
% Gravel
Fine Coarse Medium
% Sand
Fine Silt
% Fines
Clay
0.0 8.1 24.9 11.5 18.1 17.2 20.2
6
i
n
.
3
i
n
.
2
i
n
.
1½
i
n
.
1
i
n
.
¾ i
n
.
½ i
n
.
3/
8
i
n
.
#4 #1
0
#2
0
#3
0
#4
0
#6
0
#1
0
0
#1
4
0
#2
0
0
Particle Size Distribution Report
Tested By: WJC Checked By:
7-10-2019
21
(no specification provided)
PL= LL= PI=
D90= D85= D60=
D50= D30= D15=
D10= Cu= Cc=
USCS= AASHTO=
*
Clayey SAND
3/4"
1/2"
3/8"
#4
#10
#20
#40
#60
#80
#100
#200
100.0
97.8
97.0
95.6
94.1
92.6
88.9
81.6
73.5
67.6
46.9
0.4889 0.3043 0.1178
0.0837
SC
Report No. A-19605-206
Homebase Partners
North Central Development
Bozeman, Montana
B20-068-001
Material Description
Atterberg Limits
Coefficients
Classification
Remarks
Location: B-3
Sample Number: A-19605 Depth: 30.8 - 31.5 ft Date:
Client:
Project:
Project No: Figure
SIEVE PERCENT SPEC. *PASS?
SIZE FINER PERCENT (X=NO)
PE
R
C
E
N
T
F
I
N
E
R
0
10
20
30
40
50
60
70
80
90
100
GRAIN SIZE - mm.
0.0001 0.001 0.01 0.1 110 100
% +3" Coarse
% Gravel
Fine Coarse Medium
% Sand
Fine Silt
% Fines
Clay
0.0 0.0 4.4 1.5 5.2 42.0 46.9
6
i
n
.
3
i
n
.
2
i
n
.
1½
i
n
.
1
i
n
.
¾ i
n
.
½ i
n
.
3/
8
i
n
.
#4 #1
0
#2
0
#3
0
#4
0
#6
0
#1
0
0
#1
4
0
#2
0
0
Particle Size Distribution Report
Tested By: KR Checked By:
7-10-2019
22
(no specification provided)
PL= LL= PI=
D90= D85= D60=
D50= D30= D15=
D10= Cu= Cc=
USCS= AASHTO=
*
Clayey SAND with Gravel
1.5"
1"
3/4"
1/2"
3/8"
#4
#10
#20
#40
#60
#80
#100
#200
100.0
93.4
86.4
79.7
75.6
66.1
55.8
45.9
37.1
32.1
29.0
27.2
22.0
22.0867 17.8452 2.8886
1.1895 0.1996
Report No. A-19608-206
Homebase Partners
North Central Development
Bozeman, Montana
B20-068-001
Material Description
Atterberg Limits
Coefficients
Classification
Remarks
Location: B-4
Sample Number: A-19608 COMP Depth: 7.5 - 30.4 ft Date:
Client:
Project:
Project No: Figure
SIEVE PERCENT SPEC. *PASS?
SIZE FINER PERCENT (X=NO)
PE
R
C
E
N
T
F
I
N
E
R
0
10
20
30
40
50
60
70
80
90
100
GRAIN SIZE - mm.
0.0001 0.001 0.01 0.1 110 100
% +3" Coarse
% Gravel
Fine Coarse Medium
% Sand
Fine Silt
% Fines
Clay
0.0 13.6 20.3 10.3 18.7 15.1 22.0
6
i
n
.
3
i
n
.
2
i
n
.
1½
i
n
.
1
i
n
.
¾ i
n
.
½ i
n
.
3/
8
i
n
.
#4 #1
0
#2
0
#3
0
#4
0
#6
0
#1
0
0
#1
4
0
#2
0
0
Particle Size Distribution Report
Tested By: TF Checked By:
9-29-2020
23
(no specification provided)
PL= LL= PI=
D90= D85= D60=
D50= D30= D15=
D10= Cu= Cc=
USCS= AASHTO=
*
Clayey SAND with Gravel
1.5"
1"
3/4"
1/2"
3/8"
#4
#10
#20
#40
#60
#80
#100
#200
100.0
97.5
93.5
88.5
83.8
71.1
56.7
40.0
28.1
23.6
21.2
19.9
16.4
14.2148 10.2085 2.4271
1.4008 0.4894
SC
Report No. A-21719COMP-206
Homebase Partners
North Central Development
Bozeman, Montana
B20-068-001
Material Description
Atterberg Limits
Coefficients
Classification
Remarks
Location: B-5
Sample Number: A-21719 Comp Depth: 10.0 - 20.2 ft Date:
Client:
Project:
Project No: Figure
SIEVE PERCENT SPEC. *PASS?
SIZE FINER PERCENT (X=NO)
PE
R
C
E
N
T
F
I
N
E
R
0
10
20
30
40
50
60
70
80
90
100
GRAIN SIZE - mm.
0.0001 0.001 0.01 0.1 110 100
% +3" Coarse
% Gravel
Fine Coarse Medium
% Sand
Fine Silt
% Fines
Clay
0.0 6.5 22.4 14.4 28.6 11.7 16.4
6
i
n
.
3
i
n
.
2
i
n
.
1½
i
n
.
1
i
n
.
¾ i
n
.
½ i
n
.
3/
8
i
n
.
#4 #1
0
#2
0
#3
0
#4
0
#6
0
#1
0
0
#1
4
0
#2
0
0
Particle Size Distribution Report
Tested By: NJJ Checked By:
9-29-2020
24
(no specification provided)
PL= LL= PI=
D90= D85= D60=
D50= D30= D15=
D10= Cu= Cc=
USCS= AASHTO=
*
Clayey SAND with Gravel
1.5"
1"
3/4"
1/2"
3/8"
#4
#10
#20
#40
#60
#80
#100
#200
100.0
98.8
96.3
89.2
84.2
75.3
68.2
63.8
59.4
55.5
52.8
51.1
45.9
23 41 18
13.2404 9.9949 0.4662
0.1320
SC A-7-6(5)
Report No. A-21725COMP-206
Homebase Partners
North Central Development
Bozeman, Montana
B20-068-001
Material Description
Atterberg Limits
Coefficients
Classification
Remarks
Location: B-6 / B-10
Sample Number: A-21725 Comp Depth: 2.0 - 5.0 ft Date:
Client:
Project:
Project No: Figure
SIEVE PERCENT SPEC. *PASS?
SIZE FINER PERCENT (X=NO)
PE
R
C
E
N
T
F
I
N
E
R
0
10
20
30
40
50
60
70
80
90
100
GRAIN SIZE - mm.
0.0001 0.001 0.01 0.1 110 100
% +3" Coarse
% Gravel
Fine Coarse Medium
% Sand
Fine Silt
% Fines
Clay
0.0 3.7 21.0 7.1 8.8 13.5 45.9
6
i
n
.
3
i
n
.
2
i
n
.
1½
i
n
.
1
i
n
.
¾ i
n
.
½ i
n
.
3/
8
i
n
.
#4 #1
0
#2
0
#3
0
#4
0
#6
0
#1
0
0
#1
4
0
#2
0
0
Particle Size Distribution Report
Tested By: WJC Checked By:
9-29-2020
25
(no specification provided)
PL= LL= PI=
D90= D85= D60=
D50= D30= D15=
D10= Cu= Cc=
USCS= AASHTO=
*
Sandy Lean CLAY
#4
#10
#20
#40
#60
#80
#100
#200
100.0
99.9
99.7
98.1
93.8
88.3
83.8
65.9
0.1953 0.1573
CL
Report No. A-21733-206
Homebase Partners
North Central Development
Bozeman, Montana
B20-068-001
Material Description
Atterberg Limits
Coefficients
Classification
Remarks
Location: B-7
Sample Number: A-21733 Depth: 2.5 - 4.0 ft Date:
Client:
Project:
Project No: Figure
SIEVE PERCENT SPEC. *PASS?
SIZE FINER PERCENT (X=NO)
PE
R
C
E
N
T
F
I
N
E
R
0
10
20
30
40
50
60
70
80
90
100
GRAIN SIZE - mm.
0.0001 0.001 0.01 0.1 110 100
% +3" Coarse
% Gravel
Fine Coarse Medium
% Sand
Fine Silt
% Fines
Clay
0.0 0.0 0.0 0.1 1.8 32.2 65.9
6
i
n
.
3
i
n
.
2
i
n
.
1½
i
n
.
1
i
n
.
¾ i
n
.
½ i
n
.
3/
8
i
n
.
#4 #1
0
#2
0
#3
0
#4
0
#6
0
#1
0
0
#1
4
0
#2
0
0
Particle Size Distribution Report
Tested By: WJC/NJ Checked By:
10-6-2020
26
(no specification provided)
PL= LL= PI=
D90= D85= D60=
D50= D30= D15=
D10= Cu= Cc=
USCS= AASHTO=
*
Clayey GRAVEL with Sand
3"
1.5"
1"
3/4"
1/2"
3/8"
#4
#10
#20
#40
#60
#80
#100
#200
100.0
97.8
89.5
82.2
68.0
59.5
43.2
33.0
26.8
22.1
19.3
17.6
16.5
13.7
25.9004 21.0487 9.7172
6.5814 1.3400 0.1085
GC
Report No. A-21737-206
Homebase Partners
North Central Development
Bozeman, Montana
B20-068-001
Material Description
Atterberg Limits
Coefficients
Classification
Remarks
Location: B-7
Sample Number: A-21737 Depth: 10.0 - 11.5 ft Date:
Client:
Project:
Project No: Figure
SIEVE PERCENT SPEC. *PASS?
SIZE FINER PERCENT (X=NO)
PE
R
C
E
N
T
F
I
N
E
R
0
10
20
30
40
50
60
70
80
90
100
GRAIN SIZE - mm.
0.0001 0.001 0.01 0.1 110 100
% +3" Coarse
% Gravel
Fine Coarse Medium
% Sand
Fine Silt
% Fines
Clay
0.0 17.8 39.0 10.2 10.9 8.4 13.7
6
i
n
.
3
i
n
.
2
i
n
.
1½
i
n
.
1
i
n
.
¾ i
n
.
½ i
n
.
3/
8
i
n
.
#4 #1
0
#2
0
#3
0
#4
0
#6
0
#1
0
0
#1
4
0
#2
0
0
Particle Size Distribution Report
Tested By: WJC Checked By:
9-29-2020
27
(no specification provided)
PL= LL= PI=
D90= D85= D60=
D50= D30= D15=
D10= Cu= Cc=
USCS= AASHTO=
*
Lean CLAY with Sand
3/4"
1/2"
3/8"
#4
#10
#20
#40
#60
#80
#100
#200
100.0
97.7
95.9
94.4
93.6
93.1
92.5
91.5
90.1
88.8
80.5
0.1766 0.1049
CL
Report No. A-21743-206
Homebase Partners
North Central Development
Bozeman, Montana
B20-068-001
Material Description
Atterberg Limits
Coefficients
Classification
Remarks
Location: B-8
Sample Number: A-21743 Depth: 5.0 - 6.5 ft Date:
Client:
Project:
Project No: Figure
SIEVE PERCENT SPEC. *PASS?
SIZE FINER PERCENT (X=NO)
PE
R
C
E
N
T
F
I
N
E
R
0
10
20
30
40
50
60
70
80
90
100
GRAIN SIZE - mm.
0.0001 0.001 0.01 0.1 110 100
% +3" Coarse
% Gravel
Fine Coarse Medium
% Sand
Fine Silt
% Fines
Clay
0.0 0.0 5.6 0.8 1.1 12.0 80.5
6
i
n
.
3
i
n
.
2
i
n
.
1½
i
n
.
1
i
n
.
¾ i
n
.
½ i
n
.
3/
8
i
n
.
#4 #1
0
#2
0
#3
0
#4
0
#6
0
#1
0
0
#1
4
0
#2
0
0
Particle Size Distribution Report
Tested By: WJC Checked By:
9-29-2020
28
(no specification provided)
PL= LL= PI=
D90= D85= D60=
D50= D30= D15=
D10= Cu= Cc=
USCS= AASHTO=
*
Sandy Lean CLAY
3/4"
1/2"
3/8"
#4
#10
#20
#40
#60
#80
#100
#200
100.0
98.4
98.4
98.0
97.0
95.9
94.3
90.9
86.0
81.6
64.4
0.2298 0.1720
CL
Report No. A-21750-206
Homebase Partners
North Central Development
Bozeman, Montana
B20-068-001
Material Description
Atterberg Limits
Coefficients
Classification
Remarks
Location: B-9
Sample Number: A-21750 Depth: 2.5 - 4.0 ft Date:
Client:
Project:
Project No: Figure
SIEVE PERCENT SPEC. *PASS?
SIZE FINER PERCENT (X=NO)
PE
R
C
E
N
T
F
I
N
E
R
0
10
20
30
40
50
60
70
80
90
100
GRAIN SIZE - mm.
0.0001 0.001 0.01 0.1 110 100
% +3" Coarse
% Gravel
Fine Coarse Medium
% Sand
Fine Silt
% Fines
Clay
0.0 0.0 2.0 1.0 2.7 29.9 64.4
6
i
n
.
3
i
n
.
2
i
n
.
1½
i
n
.
1
i
n
.
¾ i
n
.
½ i
n
.
3/
8
i
n
.
#4 #1
0
#2
0
#3
0
#4
0
#6
0
#1
0
0
#1
4
0
#2
0
0
Particle Size Distribution Report
Tested By: NJJ Checked By:
9-30-2020
29
(no specification provided)
PL= LL= PI=
D90= D85= D60=
D50= D30= D15=
D10= Cu= Cc=
USCS= AASHTO=
*
Clayey SAND with Gravel
1"
3/4"
1/2"
3/8"
#4
#10
#20
#40
#60
#80
#100
#200
100.0
99.2
94.4
89.9
76.6
61.1
48.3
38.2
30.1
24.6
21.7
14.7
9.5805 7.2717 1.8619
0.9554 0.2484 0.0784
SC
Report No. A-21751-206
Homebase Partners
North Central Development
Bozeman, Montana
B20-068-001
Material Description
Atterberg Limits
Coefficients
Classification
Remarks
Location: B-9
Sample Number: A-21751 Depth: 6.0 - 7.0 ft Date:
Client:
Project:
Project No: Figure
SIEVE PERCENT SPEC. *PASS?
SIZE FINER PERCENT (X=NO)
PE
R
C
E
N
T
F
I
N
E
R
0
10
20
30
40
50
60
70
80
90
100
GRAIN SIZE - mm.
0.0001 0.001 0.01 0.1 110 100
% +3" Coarse
% Gravel
Fine Coarse Medium
% Sand
Fine Silt
% Fines
Clay
0.0 0.8 22.6 15.5 22.9 23.5 14.7
6
i
n
.
3
i
n
.
2
i
n
.
1½
i
n
.
1
i
n
.
¾ i
n
.
½ i
n
.
3/
8
i
n
.
#4 #1
0
#2
0
#3
0
#4
0
#6
0
#1
0
0
#1
4
0
#2
0
0
Particle Size Distribution Report
Tested By: TF Checked By:
9-29-2020
30
(no specification provided)
PL= LL= PI=
D90= D85= D60=
D50= D30= D15=
D10= Cu= Cc=
USCS= AASHTO=
*
Clayey SAND with Gravel
1.5"
1"
3/4"
1/2"
3/8"
#4
#10
#20
#40
#60
#80
#100
#200
100.0
96.6
91.1
86.0
83.0
78.4
73.5
68.6
61.4
52.6
45.0
37.2
22.0
17.8141 11.5965 0.3878
0.2155 0.1209
SC
Report No. A-21756COMP-206
Homebase Partners
North Central Development
Bozeman, Montana
B20-068-001
Material Description
Atterberg Limits
Coefficients
Classification
Remarks
Location: B-9
Sample Number: A-21756 Comp Depth: 25.0 - 30.8 ft Date:
Client:
Project:
Project No: Figure
SIEVE PERCENT SPEC. *PASS?
SIZE FINER PERCENT (X=NO)
PE
R
C
E
N
T
F
I
N
E
R
0
10
20
30
40
50
60
70
80
90
100
GRAIN SIZE - mm.
0.0001 0.001 0.01 0.1 110 100
% +3" Coarse
% Gravel
Fine Coarse Medium
% Sand
Fine Silt
% Fines
Clay
0.0 8.9 12.7 4.9 12.1 39.4 22.0
6
i
n
.
3
i
n
.
2
i
n
.
1½
i
n
.
1
i
n
.
¾ i
n
.
½ i
n
.
3/
8
i
n
.
#4 #1
0
#2
0
#3
0
#4
0
#6
0
#1
0
0
#1
4
0
#2
0
0
Particle Size Distribution Report
Tested By: WJC Checked By:
9-29-2020
31
(no specification provided)
PL= LL= PI=
D90= D85= D60=
D50= D30= D15=
D10= Cu= Cc=
USCS= AASHTO=
*
Sandy SILT
3/8"
#4
#10
#20
#40
#60
#80
#100
#200
100.0
99.8
98.4
94.9
90.4
84.9
79.4
75.2
60.2
0.4050 0.2528
ML
Report No. A-21769-206
Homebase Partners
North Central Development
Bozeman, Montana
B20-068-001
Material Description
Atterberg Limits
Coefficients
Classification
Remarks
Location: B-11
Sample Number: A-21769 Depth: 5.0 - 6.5 ft Date:
Client:
Project:
Project No: Figure
SIEVE PERCENT SPEC. *PASS?
SIZE FINER PERCENT (X=NO)
PE
R
C
E
N
T
F
I
N
E
R
0
10
20
30
40
50
60
70
80
90
100
GRAIN SIZE - mm.
0.0001 0.001 0.01 0.1 110 100
% +3" Coarse
% Gravel
Fine Coarse Medium
% Sand
Fine Silt
% Fines
Clay
0.0 0.0 0.2 1.4 8.0 30.2 60.2
6
i
n
.
3
i
n
.
2
i
n
.
1½
i
n
.
1
i
n
.
¾ i
n
.
½ i
n
.
3/
8
i
n
.
#4 #1
0
#2
0
#3
0
#4
0
#6
0
#1
0
0
#1
4
0
#2
0
0
Particle Size Distribution Report
Tested By: WJC Checked By:
9-29-2020
32
(no specification provided)
PL= LL= PI=
D90= D85= D60=
D50= D30= D15=
D10= Cu= Cc=
USCS= AASHTO=
*
Clayey SAND with Gravel
1.5"
1"
3/4"
1/2"
3/8"
#4
#10
#20
#40
#60
#80
#100
#200
100.0
96.5
92.9
83.9
80.0
71.7
62.6
54.6
45.3
35.8
28.3
24.0
16.0
16.5997 13.3962 1.4910
0.5844 0.1936
SC
Report No. A-21774COMP-206
Homebase Partners
North Central Development
Bozeman, Montana
B20-068-001
Material Description
Atterberg Limits
Coefficients
Classification
Remarks
Location: B-11
Sample Number: A-21774 Comp Depth: 25.0 - 31.8 ft Date:
Client:
Project:
Project No: Figure
SIEVE PERCENT SPEC. *PASS?
SIZE FINER PERCENT (X=NO)
PE
R
C
E
N
T
F
I
N
E
R
0
10
20
30
40
50
60
70
80
90
100
GRAIN SIZE - mm.
0.0001 0.001 0.01 0.1 110 100
% +3" Coarse
% Gravel
Fine Coarse Medium
% Sand
Fine Silt
% Fines
Clay
0.0 7.1 21.2 9.1 17.3 29.3 16.0
6
i
n
.
3
i
n
.
2
i
n
.
1½
i
n
.
1
i
n
.
¾ i
n
.
½ i
n
.
3/
8
i
n
.
#4 #1
0
#2
0
#3
0
#4
0
#6
0
#1
0
0
#1
4
0
#2
0
0
Particle Size Distribution Report
Tested By: WJC Checked By:
9-29-2020
33
(no specification provided)
PL= LL= PI=
D90= D85= D60=
D50= D30= D15=
D10= Cu= Cc=
USCS= AASHTO=
*
Clayey SAND
3/4"
1/2"
3/8"
#4
#10
#20
#40
#60
#80
#100
#200
100.0
98.2
96.3
92.4
84.7
76.0
67.0
60.1
55.0
51.7
42.0
3.4723 2.0608 0.2485
0.1356
SC
Report No. A-21778-206
Homebase Partners
North Central Development
Bozeman, Montana
B20-068-001
Material Description
Atterberg Limits
Coefficients
Classification
Remarks
Location: B-12
Sample Number: A-21778 Depth: 7.0 - 8.0 ft Date:
Client:
Project:
Project No: Figure
SIEVE PERCENT SPEC. *PASS?
SIZE FINER PERCENT (X=NO)
PE
R
C
E
N
T
F
I
N
E
R
0
10
20
30
40
50
60
70
80
90
100
GRAIN SIZE - mm.
0.0001 0.001 0.01 0.1 110 100
% +3" Coarse
% Gravel
Fine Coarse Medium
% Sand
Fine Silt
% Fines
Clay
0.0 0.0 7.6 7.7 17.7 25.0 42.0
6
i
n
.
3
i
n
.
2
i
n
.
1½
i
n
.
1
i
n
.
¾ i
n
.
½ i
n
.
3/
8
i
n
.
#4 #1
0
#2
0
#3
0
#4
0
#6
0
#1
0
0
#1
4
0
#2
0
0
Particle Size Distribution Report
Tested By: TF Checked By:
9-24-20
34
(no specification provided)
PL= LL= PI=
D90= D85= D60=
D50= D30= D15=
D10= Cu= Cc=
USCS= AASHTO=
*
Clayey GRAVEL with Sand
1.5"
1"
3/4"
1/2"
3/8"
#4
#10
#20
#40
#60
#80
#100
#200
100.0
90.7
80.4
71.1
63.1
49.9
36.9
28.5
23.5
20.5
18.7
17.5
14.2
24.8488 21.6951 8.4070
4.7957 1.0188 0.0903
GC
Report No. A-21779COMP-206
Homebase Partners
North Central Development
Bozeman, Montana
B20-068-001
Material Description
Atterberg Limits
Coefficients
Classification
Remarks
Location: B-12
Sample Number: A-21779 COMP Depth: 10.0 - 20.5 ft Date:
Client:
Project:
Project No: Figure
SIEVE PERCENT SPEC. *PASS?
SIZE FINER PERCENT (X=NO)
PE
R
C
E
N
T
F
I
N
E
R
0
10
20
30
40
50
60
70
80
90
100
GRAIN SIZE - mm.
0.0001 0.001 0.01 0.1 110 100
% +3" Coarse
% Gravel
Fine Coarse Medium
% Sand
Fine Silt
% Fines
Clay
0.0 19.6 30.5 13.0 13.4 9.3 14.2
6
i
n
.
3
i
n
.
2
i
n
.
1½
i
n
.
1
i
n
.
¾ i
n
.
½ i
n
.
3/
8
i
n
.
#4 #1
0
#2
0
#3
0
#4
0
#6
0
#1
0
0
#1
4
0
#2
0
0
Particle Size Distribution Report
Tested By: NJJ/TF Checked By:
10-8-2020
35
(no specification provided)
PL= LL= PI=
D90= D85= D60=
D50= D30= D15=
D10= Cu= Cc=
USCS= AASHTO=
*
Clayey GRAVEL with Sand
3"
1.5"
1"
3/4"
1/2"
3/8"
#4
#10
#20
#40
#60
#80
#100
#200
100.0
95.0
87.0
80.3
73.4
69.8
63.6
55.2
47.9
41.8
37.4
34.6
32.9
27.4
29.0685 23.3821 3.2413
1.0882 0.1062
GC
Report No. A-21790-206
Homebase Partners
North Central Development
Bozeman, Montana
B20-068-001
Material Description
Atterberg Limits
Coefficients
Classification
Remarks
Location: B-13
Sample Number: A-21790 Depth: 15.0 - 20.0 ft Date:
Client:
Project:
Project No: Figure
SIEVE PERCENT SPEC. *PASS?
SIZE FINER PERCENT (X=NO)
PE
R
C
E
N
T
F
I
N
E
R
0
10
20
30
40
50
60
70
80
90
100
GRAIN SIZE - mm.
0.0001 0.001 0.01 0.1 110 100
% +3" Coarse
% Gravel
Fine Coarse Medium
% Sand
Fine Silt
% Fines
Clay
0.0 19.7 16.7 8.4 13.4 14.4 27.4
6
i
n
.
3
i
n
.
2
i
n
.
1½
i
n
.
1
i
n
.
¾ i
n
.
½ i
n
.
3/
8
i
n
.
#4 #1
0
#2
0
#3
0
#4
0
#6
0
#1
0
0
#1
4
0
#2
0
0
Particle Size Distribution Report
Tested By: MS Checked By:
LIQUID AND PLASTIC LIMITS TEST REPORT
PL
A
S
T
I
C
I
T
Y
I
N
D
E
X
0
10
20
30
40
50
60
LIQUID LIMIT
0 10 20 30 40 50 60 70 80 90 100 110
CL-ML
C L o r O L
C H o r O H
ML or OL MH or OH
Dashed line indicates the approximate
upper limit boundary for natural soils
47
WA
T
E
R
C
O
N
T
E
N
T
32.8
33.2
33.6
34
34.4
34.8
35.2
35.6
36
36.4
36.8
NUMBER OF BLOWS
5 6 7 8 9 10 20 25 30 40
MATERIAL DESCRIPTION LL PL PI %<#40 %<#200 USCS
Project No. Client: Remarks:
Project:
Location: B-1
Sample Number: A-19582 Depth: 3.0 - 4.5 ft
Figure
Sandy Lean CLAY 35 21 14 CL
B20-068- Homebase Partners
36
Report No. A-19582-207
Date: 7-10-2019 North Central Development
Bozeman, Montana
Tested By: MS Checked By:
LIQUID AND PLASTIC LIMITS TEST REPORT
PL
A
S
T
I
C
I
T
Y
I
N
D
E
X
0
10
20
30
40
50
60
LIQUID LIMIT
0 10 20 30 40 50 60 70 80 90 100 110
CL-ML
C L o r O L
C H o r O H
ML or OL MH or OH
Dashed line indicates the approximate
upper limit boundary for natural soils
47
WA
T
E
R
C
O
N
T
E
N
T
34.4
34.8
35.2
35.6
36
36.4
36.8
37.2
37.6
38
38.4
NUMBER OF BLOWS
5 6 7 8 9 10 20 25 30 40
MATERIAL DESCRIPTION LL PL PI %<#40 %<#200 USCS
Project No. Client: Remarks:
Project:
Location: B-2
Sample Number: A-19590 Depth: 5.0 - 6.5 ft
Figure
Sandy Lean CLAY 36 23 13 CL
B20-068- Homebase Partners
37
Report No. A-19590-207
Date: 7-10-2019 North Central Development
Bozeman, Montana
Tested By: MS Checked By:
LIQUID AND PLASTIC LIMITS TEST REPORT
PL
A
S
T
I
C
I
T
Y
I
N
D
E
X
0
10
20
30
40
50
60
LIQUID LIMIT
0 10 20 30 40 50 60 70 80 90 100 110
CL-ML
C L o r O L
C H o r O H
ML or OL MH or OH
Dashed line indicates the approximate
upper limit boundary for natural soils
47
WA
T
E
R
C
O
N
T
E
N
T
35.6
36
36.4
36.8
37.2
37.6
38
38.4
38.8
39.2
39.6
NUMBER OF BLOWS
5 6 7 8 9 10 20 25 30 40
MATERIAL DESCRIPTION LL PL PI %<#40 %<#200 USCS
Project No. Client: Remarks:
Project:
Location: B-3
Sample Number: A-19599 Depth: 7.5 - 9.0 ft
Figure
Sandy Lean CLAY 38 21 17 CL
B20-068- Homebase Partners
38
Report No. A-19599-207
Date: 7-10-2019 North Central Development
Bozeman, Montana
Tested By: BC Checked By:
LIQUID AND PLASTIC LIMITS TEST REPORT
PL
A
S
T
I
C
I
T
Y
I
N
D
E
X
0
10
20
30
40
50
60
LIQUID LIMIT
0 10 20 30 40 50 60 70 80 90 100 110
CL-ML
C L o r O L
C H o r O H
ML or OL MH or OH
Dashed line indicates the approximate
upper limit boundary for natural soils
47
WA
T
E
R
C
O
N
T
E
N
T
35
35.4
35.8
36.2
36.6
37
37.4
37.8
38.2
38.6
39
NUMBER OF BLOWS
5 6 7 8 9 10 20 25 30 40
MATERIAL DESCRIPTION LL PL PI %<#40 %<#200 USCS
Project No. Client: Remarks:
Project:
Location: B-4
Sample Number: A-19607 Depth: 5.0 - 6.5 ft
Figure
Sandy Lean CLAY 37 18 19 CL
B20-068- Homebase Partners
39
Report No. A-19607-207
Date: 7-11-2019 North Central Development
Bozeman, Montana
Tested By: WJC Checked By:
LIQUID AND PLASTIC LIMITS TEST REPORT
PL
A
S
T
I
C
I
T
Y
I
N
D
E
X
0
10
20
30
40
50
60
LIQUID LIMIT
0 10 20 30 40 50 60 70 80 90 100 110
CL-ML
C L o r O L
C H o r O H
ML or OL MH or OH
Dashed line indicates the approximate
upper limit boundary for natural soils
47
WA
T
E
R
C
O
N
T
E
N
T
34.8
35.2
35.6
36
36.4
36.8
37.2
37.6
38
38.4
38.8
NUMBER OF BLOWS
5 6 7 8 9 10 20 25 30 40
MATERIAL DESCRIPTION LL PL PI %<#40 %<#200 USCS
Project No. Client: Remarks:
Project:
Location: B-5
Sample Number: A-21715 Depth: 2.5 - 4.0 ft
Figure
Sandy Lean CLAY 37 22 15 CL
B20-068- Homebase Partners
40
Report No. A-21715-207
Date: 9-29-2020 North Central Development
Bozeman, Montana
Tested By: NJJ Checked By:
LIQUID AND PLASTIC LIMITS TEST REPORT
PL
A
S
T
I
C
I
T
Y
I
N
D
E
X
0
10
20
30
40
50
60
LIQUID LIMIT
0 10 20 30 40 50 60 70 80 90 100 110
CL-ML
C L o r O L
C H o r O H
ML or OL MH or OH
Dashed line indicates the approximate
upper limit boundary for natural soils
47
WA
T
E
R
C
O
N
T
E
N
T
39.2
39.6
40
40.4
40.8
41.2
41.6
42
42.4
42.8
43.2
NUMBER OF BLOWS
5 6 7 8 9 10 20 25 30 40
MATERIAL DESCRIPTION LL PL PI %<#40 %<#200 USCS
Project No. Client: Remarks:
Project:
Location: B-6 / B-10
Sample Number: A-21725 Comp Depth: 2.0 - 5.0 ft
Figure
Clayey SAND with Gravel 41 23 18 59.4 45.9 SC
B20-068- Homebase Partners
41
Report No. A-21725COMP-207
Date: 9-30-2020 North Central Development
Bozeman, Montana
Tested By: NJJ Checked By:
LIQUID AND PLASTIC LIMITS TEST REPORT
PL
A
S
T
I
C
I
T
Y
I
N
D
E
X
0
10
20
30
40
50
60
LIQUID LIMIT
0 10 20 30 40 50 60 70 80 90 100 110
CL-ML
C L o r O L
C H o r O H
ML or OL MH or OH
Dashed line indicates the approximate
upper limit boundary for natural soils
47
WA
T
E
R
C
O
N
T
E
N
T
31.1
31.3
31.5
31.7
31.9
32.1
32.3
32.5
32.7
32.9
33.1
NUMBER OF BLOWS
5 6 7 8 9 10 20 25 30 40
MATERIAL DESCRIPTION LL PL PI %<#40 %<#200 USCS
Project No. Client: Remarks:
Project:
Location: B-8
Sample Number: A-21742 Depth: 2.5 - 4.0 ft
Figure
Lean CLAY with Sand 32 20 12 CL
B20-068- Homebase Partners
42
Report No. A-21742-207
Date: 9-24-20 North Central Development
Bozeman, Montana
Tested By: NJJ Checked By:
LIQUID AND PLASTIC LIMITS TEST REPORT
PL
A
S
T
I
C
I
T
Y
I
N
D
E
X
0
10
20
30
40
50
60
LIQUID LIMIT
0 10 20 30 40 50 60 70 80 90 100 110
CL-ML
C L o r O L
C H o r O H
ML or OL MH or OH
Dashed line indicates the approximate
upper limit boundary for natural soils
47
WA
T
E
R
C
O
N
T
E
N
T
35.3
35.5
35.7
35.9
36.1
36.3
36.5
36.7
36.9
37.1
37.3
NUMBER OF BLOWS
5 6 7 8 9 10 20 25 30 40
MATERIAL DESCRIPTION LL PL PI %<#40 %<#200 USCS
Project No. Client: Remarks:
Project:
Location: B-10
Sample Number: A-21762 Depth: 7.5 - 9.0 ft
Figure
Sandy Lean CLAY 36 21 15 CL
B20-068- Homebase Partners
43
Report No. A-21762-207
Date: 9-23-20 North Central Development
Bozeman, Montana
Tested By: NJJ Checked By:
LIQUID AND PLASTIC LIMITS TEST REPORT
PL
A
S
T
I
C
I
T
Y
I
N
D
E
X
0
10
20
30
40
50
60
LIQUID LIMIT
0 10 20 30 40 50 60 70 80 90 100 110
CL-ML
C L o r O L
C H o r O H
ML or OL MH or OH
Dashed line indicates the approximate
upper limit boundary for natural soils
47
WA
T
E
R
C
O
N
T
E
N
T
46.7
47.2
47.7
48.2
48.7
49.2
49.7
50.2
50.7
51.2
51.7
NUMBER OF BLOWS
5 6 7 8 9 10 20 25 30 40
MATERIAL DESCRIPTION LL PL PI %<#40 %<#200 USCS
Project No. Client: Remarks:
Project:
Location: B-11
Sample Number: A-21768 Depth: 2.5 - 4.0 ft
Figure
Sandy SILT 49 30 19 ML
B20-068- Homebase Partners
44
Report No. A-21768-207
Date: 9-29-2020 North Central Development
Bozeman, Montana
Tested By: WJC Checked By:
LIQUID AND PLASTIC LIMITS TEST REPORT
PL
A
S
T
I
C
I
T
Y
I
N
D
E
X
0
10
20
30
40
50
60
LIQUID LIMIT
0 10 20 30 40 50 60 70 80 90 100 110
CL-ML
C L o r O L
C H o r O H
ML or OL MH or OH
Dashed line indicates the approximate
upper limit boundary for natural soils
47
WA
T
E
R
C
O
N
T
E
N
T
39.6
40
40.4
40.8
41.2
41.6
42
42.4
42.8
43.2
43.6
NUMBER OF BLOWS
5 6 7 8 9 10 20 25 30 40
MATERIAL DESCRIPTION LL PL PI %<#40 %<#200 USCS
Project No. Client: Remarks:
Project:
Location: B-13
Sample Number: A-21785 Depth: 5.0 - 6.5 ft
Figure
Sandy Lean CLAY 42 25 17 CL
B20-068- Homebase Partners
45
Report No. A-21785-207
Date: 9-29-2020 North Central Development
Bozeman, Montana
Tested By: CRN Checked By:
UNCONFINED COMPRESSION TEST
Project No.: B20-068-001
Date Sampled: 9-15-2020
Remarks:
Report No. A-21716-215
Date: 9-29-2020
Figure 46
Client: Homebase Partners
Project: North Central Development
Bozeman, Montana
Location: B-5
Sample Number: A-21716 Depth: 5.0 - 7.0 ft
Description: Sandy Lean CLAY
LL = PI = PL = Assumed GS= 2.7 Type: Shelby Tube
Sample No.
Unconfined strength, psf
Undrained shear strength, psf
Failure strain, %
Strain rate, in./min.
Water content, %
Wet density, pcf
Dry density, pcf
Saturation, %
Void ratio
Specimen diameter, in.
Specimen height, in.
Height/diameter ratio
1
2773
1386
0.9
0.019
18.9
117.1
98.4
71.7
0.7126
2.82
5.61
1.99
Co
m
p
r
e
s
s
i
v
e
S
t
r
e
s
s
,
p
s
f
0
1000
2000
3000
4000
Axial Strain, %
0 0.5 1 1.5 2
1
Tested By: CRN Checked By:
UNCONFINED COMPRESSION TEST
Project No.: B20-068-001
Date Sampled: 9-16-2020
Remarks:
Report No. A-21751-215
Date: 9-29-2020
Figure 47
Client: Homebase Partners
Project: North Central Development
Bozeman, Montana
Location: B-9
Sample Number: A-21751 Depth: 5.0 - 6.0 ft
Description: Sandy Lean CLAY
LL = PI = PL = Assumed GS= 2.7 Type: Shelby Tube
Sample No.
Unconfined strength, psf
Undrained shear strength, psf
Failure strain, %
Strain rate, in./min.
Water content, %
Wet density, pcf
Dry density, pcf
Saturation, %
Void ratio
Specimen diameter, in.
Specimen height, in.
Height/diameter ratio
1
1865
933
1.1
0.020
23.0
113.1
91.9
74.6
0.8335
2.80
5.61
2.00
Co
m
p
r
e
s
s
i
v
e
S
t
r
e
s
s
,
p
s
f
0
500
1000
1500
2000
Axial Strain, %
0 0.5 1 1.5 2
1
Sat. Moist
Project No. B20-068-002 HomeBase Partners Remarks:
Project: North Central Geotech Investigation Report No. A-21716-219
Bozeman, Montana
Location: B-5 Sample Depth (ft): 5.0 - 7.0
48
Technician : CRN Reviewed By:
Client:
Figure
CONSOLIDATION TEST REPORT
AASHTO
-----
USCS
CL
MATERIAL DESCRIPTION
Sandy Lean CLAY
Natural Dry Density
(pcf) LL PI Swell
(%) eo
Sp.
Gr.
Overburden
(psf)
Pc
(psf) Cc
0.031 0.006
Cs Swell Pressure
(psf)
----- ----- 0.708 77.8 20.4 98.4 ----- ----- 2.7 710 ~ 2,000
0.00
0.20
0.40
0.60
0.80
1.00
1.20
1.40
1.60
100 1000 10000
Pe
r
c
e
n
t
S
t
r
a
i
n
Applied Pressure - psf
Sat. Moist
Project No. B20-068-002 HomeBase Partners Remarks:
Project: North Central Geotech Investigation Report No. A-21734-219
Bozeman, Montana
Location: B-7 Sample Depth (ft): 5.0 - 6.0
49
----- 0.789 74.5 21.8 93.9 ----- ----- 2.7 620 ~ 2,000 0.1 0.008
Cs Swell Pressure
(psf)
-----
Overburden
(psf)
Pc
(psf) Cc
CONSOLIDATION TEST REPORT
AASHTO
-----
USCS
CL
MATERIAL DESCRIPTION
Sandy Lean CLAY
Natural Dry Density
(pcf) LL PI Swell
(%) eo
Sp.
Gr.
Technician : CRN Reviewed By:
Client:
Figure
0.00
0.50
1.00
1.50
2.00
2.50
3.00
3.50
4.00
4.50
5.00
100 1000 10000
Pe
r
c
e
n
t
S
t
r
a
i
n
Applied Pressure - psf
Sat. Moist
Project No. B20-068-002 HomeBase Partners Remarks:
Project: North Central Geotech Investigation Report No. A-21751-219
Bozeman, Montana
Location: B-9 Sample Depth (ft): 5.0 - 6.0
50
----- 0.892 69.5 23.0 88.8 ----- ----- 2.7 600 ~ 2,000 0.107 0.008
Cs Swell Pressure
(psf)
-----
Overburden
(psf)
Pc
(psf) Cc
CONSOLIDATION TEST REPORT
AASHTO
-----
USCS
CL
MATERIAL DESCRIPTION
Sandy Lean CLAY
Natural Dry Density
(pcf) LL PI Swell
(%) eo
Sp.
Gr.
Technician : CRN Reviewed By:
Client:
Figure
0.00
1.00
2.00
3.00
4.00
5.00
6.00
100 1000 10000
Pe
r
c
e
n
t
S
t
r
a
i
n
Applied Pressure - psf
Sat. Moist
Project No. B20-068-002 HomeBase Partners Remarks:
Project: North Central Geotech Investigation Report No. A-21777-219
Bozeman, Montana
Location: B-12 Sample Depth (ft): 5.0 - 7.0
51
----- 1.017 82.5 31.1 83.3 ----- ----- 2.7 650 ~ 2,000 0.207 0.015
Cs Swell Pressure
(psf)
-----
Overburden
(psf)
Pc
(psf) Cc
CONSOLIDATION TEST REPORT
AASHTO
-----
USCS
SC
MATERIAL DESCRIPTION
Clayey SAND
Natural Dry Density
(pcf) LL PI Swell
(%) eo
Sp.
Gr.
Technician : CRN Reviewed By:
Client:
Figure
0.00
1.00
2.00
3.00
4.00
5.00
6.00
7.00
8.00
9.00
100 1000 10000
Pe
r
c
e
n
t
S
t
r
a
i
n
Applied Pressure - psf
Sat. Moist
Project No. B20-068-002 HomeBase Partners Remarks:
Project: North Central Geotech Investigation Report No. A-21795-219
Bozeman, Montana
Location: B-14 Sample Depth (ft): 5.0 - 7.0
52
----- 0.640 74.4 17.6 102.5 ----- ----- 2.7 720 ~ 2,000 0.05 0.007
Cs Swell Pressure
(psf)
-----
Overburden
(psf)
Pc
(psf) Cc
CONSOLIDATION TEST REPORT
AASHTO
-----
USCS
CL
MATERIAL DESCRIPTION
Sandy Lean CLAY
Natural Dry Density
(pcf) LL PI Swell
(%) eo
Sp.
Gr.
Technician : CRN Reviewed By:
Client:
Figure
0.00
0.50
1.00
1.50
2.00
2.50
3.00
3.50
100 1000 10000
Pe
r
c
e
n
t
S
t
r
a
i
n
Applied Pressure - psf
Tested By: MS Checked By:
Moisture-Density Test Report
Dr
y
d
e
n
s
i
t
y
,
p
c
f
95
100
105
110
115
120
Water content, %
- Rock Corrected - Uncorrected
0 5 10 15 20 25 30
12.8%, 115.6 pcf
15.2%, 109.4 pcf
ZAV for
Sp.G. =
2.70
Test specification:
ASTM D4718-15 Oversize Corr. Applied to Each Test Point
ASTM D 698-12 Method B Standard
2.0 - 5.0 ft SC A-7-6(5) 2.7 41 18 15.8 45.9
Clayey SAND with Gravel
B20-068- Homebase Partners
Report No. A-21725COMP-204
Date: 9-30-2020
53
Elev/ Classification Nat. Sp.G. LL PI % > % <
Depth USCS AASHTO Moist. 3/8 in. No.200
ROCK CORRECTED TEST RESULTS UNCORRECTED MATERIAL DESCRIPTION
Project No. Client: Remarks:
Project:
Location: B-6 / B-10 Sample Number: A-21725 Comp
Figure
109.4 pcf Maximum dry density = 115.6 pcf
15.2 % Optimum moisture = 12.8 %
North Central Development
Bozeman, Montana
BEARING RATIO TEST REPORT
ASTM D 1883-07
Project No: B20-068-001
Project: North Central Development Bozeman, Montana
Location: B-6 / B-10
Sample Number: A-21725 Comp Depth: 2.0 - 5.0 ft
Date: 9-29-2020
Clayey SAND with Gravel
Test Description/Remarks:
ASTM D698 with 6-inch mold
96-hour soak prior to testing
Report No. A-21725COMP-210
Date: 10-8-2020
Figure 54
115.6 12.8 41 18 SC
Material Description USCS
Max.
Dens.
(pcf)
Optimum
Moisture
(%)
LL PI
Molded
Density
(pcf)
Percent of
Max. Dens.
Moisture
(%)
Soaked
Density
(pcf)
Percent of
Max. Dens.
Moisture
(%)
CBR (%)
0.10 in. 0.20 in.
Linearity
Correction
(in.)
Surcharge
(lbs.)
Max.
Swell
(%)
1 100.8 87.2 11.4 100.5 87 21.3 3.1 2.5 0.000 10 0.3
2 110.6 95.7 12.6 109.9 95.1 16.6 9.0 7.9 0.000 10 0.6
3 116.8 101 11.6 116.0 100.4 15.1 14.6 15.3 0.001 10 0.7
Pe
n
e
t
r
a
t
i
o
n
R
e
s
i
s
t
a
n
c
e
(
p
s
i
)
0
70
140
210
280
350
Penetration Depth (in.)
0 0.1 0.2 0.3 0.4 0.5
Sw
e
l
l
(
%
)
0
0.2
0.4
0.6
0.8
1
Elapsed Time (hrs)
0 24 48 72 96
CB
R
(
%
)
0
5
10
15
20
Molded Density (pcf)
95 100 105 110 115 120
10 blows
25 blows
56 blows
CBR at 90% Max. Density = 3.7%
for 0.20 in. Penetration
QUALITY CHECK:
DESIGNED BY:
DRAWN BY:
CAD NO.
JOB NO.
DATE:
02801-06C
Engineering
tdhengineering.com
CONSTRUCTION STANDARD NO. 02801-06C
PERIMETER FOUNDATION DRAIN
RESIDENTIAL CONSTRUCTION
RLT
CRN
MMJ
5/21/15
FIGURE