HomeMy WebLinkAbout028_GeotechnicalReportMONTANA | WASHINGTON | IDAHO | NORTH DAKOTA | PENNSYLVANIA
JOB NO. 23-230-001 February 2024
REPORT OF GEOTECHNICAL INVESTIGATION
CLIENT ENGINEER
Bozeman TRAX Partners LLC
5157 US-89 S
Livingston, MT 59047
Craig Nadeau, PE
Craig.Nadeau@tdhengineering.com
REPORT OF GEOTECHNICAL INVESTIGATION
PROJECT NAME
PROJECT LOCATION 406.586.0277
tdhengineering.com
234 E Babcock St, Suite 3
Bozeman, MT 59715
NORTH PARK PUBLIC INFRASTRUCTURE
BOZEMAN, MONTANA
North Park Public Infrastructure Table of Contents
Bozeman, Montana i
Table of Contents
1.0 EXECUTIVE SUMMARY ......................................................................................................... 1
2.0 INTRODUCTION ..................................................................................................................... 2
2.1 Purpose and Scope .......................................................................................................... 2
2.2 Project Description ........................................................................................................... 2
3.0 SITE CONDITIONS ................................................................................................................. 3
3.1 Geology and Physiography .............................................................................................. 3
3.2 Surface Conditions ........................................................................................................... 4
3.3 Subsurface Conditions ..................................................................................................... 4
3.3.1 Soils ........................................................................................................................... 4
3.3.2 Ground Water ........................................................................................................... 6
4.0 ENGINEERING ANALYSIS .................................................................................................... 7
4.1 Site Grading and Excavations.......................................................................................... 7
4.3 Pipe Corrosion Assessment ............................................................................................. 7
4.5 Pavements ....................................................................................................................... 8
5.0 RECOMMENDATIONS ........................................................................................................... 9
5.1 Site Grading and Excavations.......................................................................................... 9
5.2 Pavements ..................................................................................................................... 10
5.3 Continuing Services ....................................................................................................... 11
6.0 SUMMARY OF FIELD AND LABORATORY STUDIES ....................................................... 13
6.1 Field Explorations ........................................................................................................... 13
6.2 Laboratory Testing ......................................................................................................... 13
7.0 LIMITATIONS ........................................................................................................................ 15
North Park Public Infrastructure Appendix
Bozeman, Montana ii
APPENDIX
Test Pit Location Map (Figure 1)
Logs of Exploratory Test Pits (Figures 2 through 9)
Laboratory Test Data (Figures 10 through 21)
Corrosion Control Design Analysis Tables & Test Results (Figures 22 through 28)
LTTPBind Online PG Asphalt Binder Analysis Summary
Soil Classification and Sampling Terminology for Engineering Purposes
Classification of Soils for Engineering Purposes
North Park Public Infrastructure Executive Summary
Bozeman, Montana Page 1
GEOTECHNICAL REPORT
NORTH PARK PUBLIC INFRASTRUCTURE
BOZEMAN, MONTANA
1.0 EXECUTIVE SUMMARY
The geotechnical investigation for the North Park public infrastructure extensions to Wheat Drive
and Cultivar Street in Bozeman, Montana encountered relatively consistent subsurface soil
conditions. In general, the project area is located on the south side of Frontage Road between
Interstate I-90 and North 7th Avenue. It is our understanding that the project consists of extending
the roadways of Wheat Drive and Cultivar Street, along with their associated utilities, throughout the
remaining portions of the North Park Development. Additionally, we understand a new sewer main
is proposed within Cultivar Street, which will extend from the southwest corner of the site and
continue north where it will tie into Frontage Road. The subsurface soil conditions consist of a
topsoil horizon exhibiting a thickness of approximately 1.0 to 1.5 feet overlying lean clay soil of
varying sand content. The clays extend to depths of 2.8 to 6.8 feet in the test pits performed and
are underlain by native gravel deposits. Similar native gravels extend to depths of at least 9.4 feet,
the maximum depth investigated.
Based on the results of the chemical analyses, the subsurface conditions pose no significant
corrosion risk to the buried utility systems for this project. However, the planned roadway
extensions will overlie limited thicknesses of relatively soft lean clay soils which are considered an
inferior subgrade material due to their poor drainage properties and decreased strength when
wetted. While compaction of the subgrade is typical in most construction projects, our experience
has shown that compaction may be difficult as areas of the site already exhibit moistures which are
elevated up to eight percent beyond their optimum level for compaction. We have accounted for the
potential difficulty of achieving compaction by using a reduced CBR value in the design of the
pavement section recommendations provided.
North Park Public Infrastructure Introduction
Bozeman, Montana Page 2
2.0 INTRODUCTION
2.1 Purpose and Scope
This report presents the results of our geotechnical study for the North Park public infrastructure
extensions to Wheat Drive and Cultivar Street in Bozeman, Montana. In general, the project area is
located on the south side of Frontage Road between Interstate I-90 and North 7th Avenue. The
purpose of the geotechnical study is to determine the general surface and subsurface conditions at
the proposed site and to develop geotechnical engineering recommendations for support of the
proposed site development infrastructure consisting of roadway sections and utilities. At this time,
no structures within the development area have been considered. This report describes the field
work and laboratory analyses conducted for this project, the surface and subsurface conditions
encountered, and presents our recommendations for the proposed site development.
Our field work included excavating eight test pits within the limits of the proposed roadways and
utility alignments to assess subsurface conditions. Samples were obtained from the test pits and
returned to our Great Falls laboratory for testing. Laboratory testing was performed on selected soil
samples to determine engineering properties of the subsurface materials. The information obtained
during our field investigations and laboratory analyses was used to develop recommendations for
the design of the proposed infrastructure extensions.
2.2 Project Description
Based on a preliminary site plan, the project is planned to extend Wheat Drive and its associated
water main towards the northwest. The roadway will dead end with a cul-de-sac turn around near
the northern corner of the site while the water main is planned to continue north where it will tie into
the existing main within the Frontage Road. The project also includes the extension of Cultivar
Street towards the east where it will then parallel interstate I-90 toward the north and connect with
Wheat Drive. Similarly, the water main within Cultivar Street will extend from the existing
termination point and follow the roadway where it will tie into the main extension located in Wheat
Drive. However, the water main is also planned to tee near the central region of the roadway and
extend west beneath Interstate I-90. Additionally, a new sewer main is proposed within Cultivar
Street, which will extend from the southwest corner of the site and continue north where it will tie
into the Frontage Road.
Additional infrastructure improvements are anticipated to include either culvert piping systems or
stream crossing bridges to the planned roadways to provide adequate passageway for Mandeville
Creek, which runs through the site from south to north.
North Park Public Infrastructure Site Conditions
Bozeman, Montana Page 3
3.0 SITE CONDITIONS
3.1 Geology and Physiography
According to the geologic map of Montana, the site is geologically characterized as being upper
tertiary sediments or sedimentary rock (Tsu). This formation includes conglomerate, tuffaceous
sandstone and siltstone, marlstone, and equivalent sediment and ash beds. However, the map
indicates alluvial gravel deposits (Qgr) extend within a small portion of the southern boundary of the
site. These gravels range from pebbles to boulders in size and include varying amounts of sand,
silt, and clay. These deposits are dominantly alluvial terrace, abandoned channel and floodplain,
remnant alluvial fan, and local glacial outwash.
Additional data provided by the geologic map of Bozeman further classifies the site as being braid
plain alluvium (Qabo) of the Pleistocene epoch. Similar to the alluvial gravels described above, these
deposits consist of cobble to boulder size clasts containing sand, silt, and clay. The rounded to
well-rounded clasts are most commonly composed of Archean metamorphic rock, and dark colored
volcanic rock, with subordinate Paleozoic limestone and Proterozoic Belt rocks. According to the
geology report of Bozeman, an unknown well within this unit indicates a thickness of 30 feet of
alluvium overlying tertiary deposits. A nearby well log on the north side of the site suggests similar
conditions with gravels and sands intermixed with fine-grained soils extending to a depth of
approximately 30 feet. Similarly, a well log on the south side of the site suggests similar materials
extend to a depth of at least 80 feet indicating a possible downward slope of the tertiary bedrock
from north to south.
Geologic Map of Montana, Edition 1.0 (2007)
Montana Bureau of Mines & Geology
Approximate
Site Location
North Park Public Infrastructure Site Conditions
Bozeman, Montana Page 4
Geologic Map of the Bozeman, Southwestern Montana (2014)
Montana Bureau of Mines & Geology
3.2 Surface Conditions
The proposed project site is located on the south side of Frontage Road between Interstate I-90 and
North 7th Avenue and presently consists of undeveloped farmland. Based on background
information and site observations, the site generally slopes downward toward the north at slopes of
one to two percent. However, occasional slopes of up to six percent exist across portions of the
site. Additionally, Mandeville Creek runs from south to north through the center of the site which
creates undulating terrain, but generally produces similar slopes down towards the creek in the
east-west directions. The topography is best described as gently sloping downward to the north
with moderate slopes down toward the east and west near Mandeville Creek.
3.3 Subsurface Conditions
3.3.1 Soils
The subsurface soil conditions appear to be relatively consistent based on our exploratory
excavating and soil sampling. In general, the subsurface soil conditions encountered within
the test pits consists of a topsoil horizon exhibiting a thickness of 1.0 to 1.5 feet overlying
lean clay with varying amounts of sand. The clay soils extend to depths ranging from 2.8 to
6.8 feet and is underlain by native gravel deposits. Similar gravels extend to depths of at
least 9.4 feet, the maximum depth investigated.
Approximate
Site Location
North Park Public Infrastructure Site Conditions
Bozeman, Montana Page 5
The subsurface soils are described in detail on the enclosed test pit logs and are
summarized below. The stratification lines shown on the logs represent approximate
boundaries between soil types and the actual in situ transition may be gradual vertically or
discontinuous laterally.
TOPSOIL
A topsoil horizon was encountered in each test pit except test pit TP-1 and exhibited a
thickness of 1.0 to 1.5 feet. This zone was visually classified as lean clay and contained
trace organics, in the form of roots, from the overlying farm grass vegetation. The material
appears firm based on the efforts required during excavation and was predominantly frozen.
FINE-GRAINED SOILS
Lean clay was encountered in all test pits beneath the overlying topsoil horizon at depths of
1.0 to 1.5 feet. However, this zone exhibited variations in the sand content and sporadic
gravels in the northern portion of the site (TP-2 through TP-5) resulting in classifications of
lean clay with sand or gravelly lean clay. The clays extend to depths of 2.8 to 6.8 feet with
the greatest thickness observed in test pit TP-6 on the west side of the site. The clay soils
appear firm to very stiff based on the efforts required during excavation. Four samples of
the materials contained between 0.1 and 22.3 percent gravel, between 3.8 and 20.5 percent
sand, and between 64.6 and 96.1 percent fines (silt and clay). The same samples exhibited
liquid limits ranging from 35 to 39 percent and plasticity indices ranging from 15 to 19
percent. The natural moisture contents varied from 6.5 to 26.0 percent and average 18.2
percent.
A single bulk sample of the lean clay collected from TP-7 was tested in our laboratory to
evaluate its strength as a subgrade beneath pavement sections. The results of this test are
summarized below:
Material Description Maximum Dry
Density (pcf)
Optimum Moisture
Content (%)
CBR at 95%
Compaction (%)
Lean CLAY 103.7 18.3 5.0
NATIVE GRAVELS
Native gravels were encountered in all test pits beneath the overburden clays at depths of
2.8 to 6.8 feet. The gravels are primarily classified as well-graded gravel with sand,
however, test pits TP-1 through TP-3 all encountered elevated clay content in portions of the
stratum. These zones were visually classified as clayey gravel with sand. The gravel
appears dense to very dense based on observations during excavation and contain an
assorted number of cobbles, up to eight inch in diameter. Two bulk samples of the
materials contained 5.9 and 9.8 percent cobbles (larger than 3-inch), 60.8 and 57.5 percent
gravel, 29.4 and 20.7 percent sand, and 3.9 and 12.0 percent fines (silt and clay). Due to
difficulties sampling materials with large cobbles, the sample may not accurately depict the
North Park Public Infrastructure Site Conditions
Bozeman, Montana Page 6
in-situ material gradation of the native gravel. The natural moisture contents varied from 2.7
to 8.3 percent and averaged 4.7 percent.
3.3.2 Ground Water
Ground water was encountered in test pits TP-5 through TP-8 at depths ranging from 6.5 to
7.5 feet below the existing ground surface. Water levels were measured at the time of
excavation and are expected to experience seasonal fluctuations. The presence or
absence of observed ground water may be directly related to the time of the subsurface
investigation. Numerous factors contribute to seasonal ground water occurrences and
fluctuations, and the evaluation of such factors is beyond the scope of this report.
North Park Public Infrastructure Engineering Analysis
Bozeman, Montana Page 7
4.0 ENGINEERING ANALYSIS
4.1 Site Grading and Excavations
The ground surface at the proposed site is gently sloped down toward the north at slopes between
one and four percent. However, occasional slopes of up to six percent exist across portions of the
site. Additionally, Mandeville Creek runs from south to north through the center of the site which
creates similar slopes down towards the creek in the east-west directions.
Based on our field work, lean clay soils overlying native gravels will be encountered in utility
excavations to the depths anticipated. Following topsoil removal, pavement excavations are
anticipated to encounter primarily lean clay soils. However, the native gravels are relatively shallow
and are anticipated in utility trenches but depending on the final site grades may be encountered
below pavements as well. Ground water was encountered in four out of the eight test pits at depths
ranging from 6.5 to 7.5 feet below the ground surface. However, our investigation was performed
during seasonal lows and water levels are anticipated to rise depending on the magnitude of
seasonal fluctuations. Ground water monitoring or the determination of ground water fluctuations
were beyond our scope of work for this project, but site dewatering should be expected for utility
excavations exceeding six feet.
4.3 Pipe Corrosion Assessment
In accordance with the current City of Bozeman requirements, samples of the native clay and gravel
materials were sent to an outside laboratory to evaluate their chemical composition. The chemical
analyses were used in conjunction with the “Advancements in Pipe Longevity: The Design Decision
Model” paper published by the Ductile Iron Pipe Research association (DIPRA) and Corrpro
Companies to assess the subsurface conditions potential for causing corrosion to the planned
below grade infrastructure. The tables and charts used from the Design Decision Model along with
assessment tables outlining the laboratory tests performed and their results are included at the end
of this report in the appendix as Figures 22 through 24.
The method outlined in the Design Decision Model uses a scoring system to evaluate the likelihood
of corrosion and the associated consequences to determine the most appropriate protection
system. Based on the laboratory results and the project specific parameters, the likelihood score
sheet resulted in scores of 13.5 and 16.0 for the native clays and 16.0 for both samples of the
native gravels. These scores are based out of a possible 60-point scoring system as shown on
Figure 23. The consequence score sheet reflects a score of 23 of a possible 50 points (see Figure
24) which is anticipated to reflect the worst-case score for utilities in the Bozeman area. These two
scores were then plotted on the DDM Two-Dimensional Matrix (Figure 22) to obtain the
recommended protection system for the site and project constraints. All points plot in Zone 1 of the
matrix indicating the use of ductile iron pipe as manufactured with a shop coating being adequate.
North Park Public Infrastructure Engineering Analysis
Bozeman, Montana Page 8
4.5 Pavements
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. Traffic information was not available at the time of this report. We have assumed
that traffic for the roadways will be limited to passenger-type vehicles and regular single-unit truck
traffic associated with commercial vehicles. However, we anticipate the roadways will occasionally
be subject to heavier loads associated with tractor-trailer traffic. The pavement section provided
has been prepared using a maximum anticipated equivalent single axle loading (ESAL) of 100,000
over a 20-year design life of the pavement.
The worst-case subgrade material is the native lean clay which is classified as an A-6 soil, in
accordance with the American Association of State Highway and Transportation Officials (AASHTO)
classification. AASHTO considers this soil type to be an inferior subgrade material due to its poor
drainage properties and reduced strength when wetted. Typical California Bearing Ratio (CBR)
values for this type of soil range from 5 to 15 percent when the material can be properly compacted
during construction. During laboratory testing, a CBR value of 5 percent was measured assuming a
conventional compaction requirement of 95 percent would be attainable for the lean clay. However,
the in-situ moisture contents of the native clays in area were elevated up to eight percent beyond
the optimum moisture. For this reason, our pavement section has been designed using a reduced
CBR value of 2 percent which, in our experience, is consistent with materials exhibiting similar
elevated moistures. It will be necessary to compact the native soils prior to placing gravel material
associated with the pavement section. After subgrade preparation, all subsequent fill should be
selected, placed, and compacted in accordance with our recommendations.
A geotextile acting as a separator is recommended between the pavement section gravels and the
clay subgrade. The geotextile will prevent the upward migration of fines and the loss of aggregate
into the subgrade, thereby prolonging the structural integrity and performance of the pavement
section.
The pavement section presented in this report is based on a reduced CBR value of 2 percent,
assumed traffic loadings, recommended pavement section design information presented in the
Asphalt Institute and AASHTO Design Manuals, and our past pavement design experience in
Bozeman.
North Park Public Infrastructure Recommendations
Bozeman, Montana Page 9
5.0 RECOMMENDATIONS
5.1 Site Grading and Excavations
1. All topsoil and organic material should be removed from the proposed 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, are suitable for use as backfill and general site grading fill on this project,
provided they are properly moisture conditioned to levels which are conducive to
compaction.
All fill 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) Subgrade Below Pavement Systems .......................................... 92%
b) Gravels Below Pavement Systems ............................................. 95%
c) General Landscaping or Nonstructural Areas ............................. 92%
d) Utility Trench Backfill, To Within 2 Feet of Surface..................... 95%
For your consideration, 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. Site utilities should be installed with proper bedding in accordance with the pipe
manufacturer’s requirements. Chemical testing of on-site soils indicates that pipe
systems using the manufactured shop coating will be adequate and no other
protective measures are anticipated to control corrosion. If significantly differing soil
conditions are encountered on site, it is advised that these conditions be further
evaluated.
North Park Public Infrastructure Recommendations
Bozeman, Montana Page 10
4. 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 contractor is responsible for providing
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 Pavements
5. The following pavement section or an approved equivalent section should be
selected in accordance with the discussions in the Engineering Analysis.
Pavement Component Component Thickness
Asphaltic Concrete Pavement 3”
Crushed Base Course 6”
Crushed Subbase Course 12”
Total 21”
6. 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.
7. 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.
8. A geotextile is recommended between the pavement section and the prepared
subgrade to prevent the migration of fines upward into the gravel and the loss of
aggregate into the subgrade. Due to the soft subgrade conditions, a stronger Mirafi
HP570 or RS380i, or equivalent geotextile, which will help to reinforce the subgrade
to aid in proper compaction of the overlying subbase is appropriate for the site
conditions encountered.
North Park Public Infrastructure Recommendations
Bozeman, Montana Page 11
9. 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% 35.8 -30.6 PG 52-32
98% 39.8 -39.4 PG 52-40
In our experience, neither of the oil grades summarized above are available through
local suppliers and would result in additional costs associated with importing
specialized products. Thus, for this project the use of a PG 58-28 grade oil is
recommended as this product is locally available through asphalt suppliers and will
provide the highest reliability level without the added expense of importing
specialized products.
5.3 Continuing Services
Three additional elements of geotechnical engineering service are important to the successful
completion of this project.
10. 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.
11. Observation, monitoring, and testing during construction is required to document the
successful completion of all earthworks phases. A geotechnical engineer from our
firm should be retained to observe the excavation and earthwork phases of the
project to determine that subsurface conditions are compatible with those used in
the analysis and design.
12. 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:
North Park Public Infrastructure Recommendations
Bozeman, Montana Page 12
Compaction Testing
Utility Trench Backfill 1 Test per 50 LF per Lift
Paved Areas 1 Test per 1,500 SF per Lift of Subgrade
1 Test per 2,500 SF of Subbase or Base per Lift
LF = Lineal Feet SF = Square Feet
North Park Public Infrastructure Summary of Field & Laboratory Studies
Bozeman, Montana Page 13
6.0 SUMMARY OF FIELD AND LABORATORY STUDIES
6.1 Field Explorations
The field exploration program was conducted on December 21, 2023. A total of eight test pits were
excavated to depths ranging from 7.5 to 9.4 feet at the approximate locations shown on Figure 1 to
observe subsurface soil and ground water conditions. The tests pits were excavated by Earth
Surgeons Excavation using a rubber tracked CAT 305 CR mini-excavator. The subsurface
exploration and sampling methods used are indicated on the attached test pit logs. The test pits
were logged by Mr. Nic Couch, EI of TD&H Engineering.
Composite and grab samples of the subsurface materials were taken from the spoils removed
during excavation at discrete sampling locations. Logs of the test pits, which include soil
descriptions and sample depths are presented on Figures 2 through 9.
Measurements to determine the depth of ground water in the test pits were made using a steel tape
measure shortly after the completion of excavating. The depths or elevations of the water levels
measured, if encountered, and the date of measurement are shown on the test pit logs.
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 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.
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.
North Park Public Infrastructure Summary of Field & Laboratory Studies
Bozeman, Montana Page 14
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 laboratory testing program for this project consisted of 17 moisture-visual analyses, 6 sieve
(grain-size distribution) analyses, and 4 Atterberg Limits analyses. The results of the water content
analyses are presented on the test pit logs, Figures 2 through 9. The grain-size distribution curves
and Atterberg limits are presented in Figures 10 through 19. In addition, one proctor (moisture-
density) test and one California Bearing Ratio (CBR) test were performed. Results of these tests
are shown on Figures 20 and 21. Further testing was performed by Alpine Analytical Laboratory
which included four pH tests, four resistivity tests, four chloride tests, four sulfide tests, and four
redox potential tests. The results of the chemical analyses are included in the appendix and
discussed within the body of the report.
North Park Public Infrastructure Limitations
Bozeman, Montana Page 15
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 test pits 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 test pits 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 test pits 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
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 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 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 Park Public Infrastructure Limitations
Bozeman, Montana Page 16
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 test pit logs and presented in discussions of subsurface conditions
included in this report.
Prepared by: Reviewed by:
Nic Couch EI Craig Nadeau PE & Principal
Geotechnical Engineer Geotechnical Manager
TD&H ENGINEERING TD&H ENGINEERING
NORTH PARK PUBLIC INFRASTRUCTURE BOZEMAN, MONTANA APPROXIMATE TEST PIT LOCATION MAP FIGURE 1
NOTES:
THE LOCATIONS OF THE TEST PITS ARE APPROXIMATE AND ARE NOT
SURVEYED MARKINGS. LOCATIONS ARE TO BE USED FOR GENERAL
REFERENCE ONLY.
NO
SCALE
23-230 FIGURE
NCC
CRN
23-230
01.29.2024
0
1.5
3
4.5
6
7.5
9
10.5
Lean CLAY, appears stiff, brown, moist, frozen to 0.9 feet
Lean CLAY, appears soft to firm, light tan, moist, trace sand
Clayey GRAVEL with Sand, appears dense, brown to dark
brown, moist, 8-inch minus cobbles
Bottom of Test Pit
0.9
3.8
8.4
Ground
water
not
encoun-
tered
G
G
G
LEGEND LOG OF TEST PIT TP-1Atterberg Limits
Field Moisture content North Park Public Infrastructure
Bozeman, MontanaGroundwater Level
Grab/composite sample
Logged by:Nic Couch, EI
Excavated by:Earth Surgeons Excavation LLC
Rubber Tracked CAT 305 CR Mini-ExcavatorGNP = Granular and Nonplastic
Note: The stratification lines represent approximate
boundaries between soil types. Actual boundaries
may be gradual or transitional.
December 21, 2023 23-230-001
Figure No.2
SheetGRAPHICLOGSOIL DESCRIPTION
SURFACE:Unvegetated, Disturbed Soil
SURFACE ELEVATION:Not Measured
DEPTH (FT)GROUNDWATERSAMPLEDEPTH (FT)MOISTURE CONTENT
0 10 20 30 40 50
= MOISTURE CONTENT
1 of 1
0
1.5
3
4.5
6
7.5
9
10.5
TOPSOIL: Lean CLAY, appears stiff to firm, black to dark
brown, moist, organics, frozen to 0.5 feet
Lean CLAY with Sand, appears firm, light tan, moist, trace
salts
Clayey GRAVEL with Sand, appears very dense, dark
brown to brown, moist, 8-inch minus cobbles
Bottom of Test Pit
1.0
3.9
8.3
Ground
water
not
encoun-
tered
G
G
LEGEND LOG OF TEST PIT TP-2Atterberg Limits
Field Moisture content North Park Public Infrastructure
Bozeman, MontanaGroundwater Level
Grab/composite sample
Logged by:Nic Couch, EI
Excavated by:Earth Surgeons Excavation LLC
Rubber Tracked CAT 305 CR Mini-ExcavatorGNP = Granular and Nonplastic
Note: The stratification lines represent approximate
boundaries between soil types. Actual boundaries
may be gradual or transitional.
December 21, 2023 23-230-001
Figure No.3
SheetGRAPHICLOGSOIL DESCRIPTION
SURFACE:Cut Farm Field
SURFACE ELEVATION:Not Measured
DEPTH (FT)GROUNDWATERSAMPLEDEPTH (FT)MOISTURE CONTENT
0 10 20 30 40 50
= MOISTURE CONTENT
1 of 1
0
1.5
3
4.5
6
7.5
9
10.5
TOPSOIL: Lean CLAY, appears stiff to firm, black to dark
brown, moist, organics, trace gravel, frozen to 0.5 feet
Lean CLAY with Sand, appears firm to stiff, light tan, moist,
trace gravel that increases with depth
Clayey GRAVEL with Sand, appears very dense, brown,
moist, 8-inch minus cobbles
Well-Graded GRAVEL with Sand, appears dense to very
dense, dark brown, moist, 8-inch minus cobbles
Bottom of Test Pit
1.5
3.6
6.5
8.0
Ground
water
not
encoun-
tered
G
G
G
LEGEND LOG OF TEST PIT TP-3Atterberg Limits
Field Moisture content North Park Public Infrastructure
Bozeman, MontanaGroundwater Level
Grab/composite sample
Logged by:Nic Couch, EI
Excavated by:Earth Surgeons Excavation LLC
Rubber Tracked CAT 305 CR Mini-ExcavatorGNP = Granular and Nonplastic
Note: The stratification lines represent approximate
boundaries between soil types. Actual boundaries
may be gradual or transitional.
December 21, 2023 23-230-001
Figure No.4
SheetGRAPHICLOGSOIL DESCRIPTION
SURFACE:Cut Farm Field
SURFACE ELEVATION:Not Measured
DEPTH (FT)GROUNDWATERSAMPLEDEPTH (FT)MOISTURE CONTENT
0 10 20 30 40 50
= MOISTURE CONTENT
1 of 1
0
1.5
3
4.5
6
7.5
9
10.5
TOPSOIL: Lean CLAY, appears stiff, black to dark brown,
moist, organics, frozen to 0.5 feet
Gravelly Lean CLAY, appears stiff to very stiff, light tan,
moist, some sand
Well-Graded GRAVEL with Sand, appears dense to very
dense, dark brown, moist, 8-inch minus cobbles
Bottom of Test Pit
1.5
2.8
7.5
Ground
water
not
encoun-
tered
G
G
LEGEND LOG OF TEST PIT TP-4Atterberg Limits
Field Moisture content North Park Public Infrastructure
Bozeman, MontanaGroundwater Level
Grab/composite sample
Logged by:Nic Couch, EI
Excavated by:Earth Surgeons Excavation LLC
Rubber Tracked CAT 305 CR Mini-ExcavatorGNP = Granular and Nonplastic
Note: The stratification lines represent approximate
boundaries between soil types. Actual boundaries
may be gradual or transitional.
December 21, 2023 23-230-001
Figure No.5
SheetGRAPHICLOGSOIL DESCRIPTION
SURFACE:Cut Farm Field
SURFACE ELEVATION:Not Measured
DEPTH (FT)GROUNDWATERSAMPLEDEPTH (FT)MOISTURE CONTENT
0 10 20 30 40 50
= MOISTURE CONTENT
1 of 1
0
1.5
3
4.5
6
7.5
9
10.5
TOPSOIL: Lean CLAY, appears firm, black to dark brown,
moist, organics
Lean CLAY with Sand, appears soft, light tan, moist
Well-Graded GRAVEL with Sand, appears dense to very
dense, dark brown, moist to wet, 8-inch minus cobbles
Bottom of Test Pit
1.5
3.5
7.8
G
G
LEGEND LOG OF TEST PIT TP-5Atterberg Limits
Field Moisture content North Park Public Infrastructure
Bozeman, MontanaGroundwater Level
Grab/composite sample
Logged by:Nic Couch, EI
Excavated by:Earth Surgeons Excavation LLC
Rubber Tracked CAT 305 CR Mini-ExcavatorGNP = Granular and Nonplastic
Note: The stratification lines represent approximate
boundaries between soil types. Actual boundaries
may be gradual or transitional.
December 21, 2023 23-230-001
Figure No.6
SheetGRAPHICLOGSOIL DESCRIPTION
SURFACE:Cut Farm Field
SURFACE ELEVATION:Not Measured
DEPTH (FT)GROUNDWATERSAMPLEDEPTH (FT)MOISTURE CONTENT
0 10 20 30 40 50
= MOISTURE CONTENT
1 of 1
0
1.5
3
4.5
6
7.5
9
10.5
TOPSOIL: Lean CLAY, appears stiff, black to dark brown,
moist, organics, frozen 0.5 feet
Lean CLAY, appears soft, light tan, moist
- Very moist below 5.0 feet
Well-Graded GRAVEL with Sand, appears dense to very
dense, dark brown, very moist to wet, 8-inch minus cobbles
Bottom of Test Pit
1.1
6.8
9.4
G
LEGEND LOG OF TEST PIT TP-6Atterberg Limits
Field Moisture content North Park Public Infrastructure
Bozeman, MontanaGroundwater Level
Grab/composite sample
Logged by:Nic Couch, EI
Excavated by:Earth Surgeons Excavation LLC
Rubber Tracked CAT 305 CR Mini-ExcavatorGNP = Granular and Nonplastic
Note: The stratification lines represent approximate
boundaries between soil types. Actual boundaries
may be gradual or transitional.
December 21, 2023 23-230-001
Figure No.7
SheetGRAPHICLOGSOIL DESCRIPTION
SURFACE:Cut Farm Field
SURFACE ELEVATION:Not Measured
DEPTH (FT)GROUNDWATERSAMPLEDEPTH (FT)MOISTURE CONTENT
0 10 20 30 40 50
= MOISTURE CONTENT
1 of 1
0
1.5
3
4.5
6
7.5
9
10.5
TOPSOIL: Lean CLAY, appears stiff, black to brown, moist,
organics, frozen to 0.5 feet
Lean CLAY, appears soft, light tan, moist
- See Figures 20 and 21 for moisture density relationship
and CBR test result
Well-Graded GRAVEL with Sand, appears dense to very
dense, dark brown, very moist to wet, 8-inch minus cobbles
Bottom of Test Pit
1.3
4.9
7.9
G
G
LEGEND LOG OF TEST PIT TP-7Atterberg Limits
Field Moisture content North Park Public Infrastructure
Bozeman, MontanaGroundwater Level
Grab/composite sample
Logged by:Nic Couch, EI
Excavated by:Earth Surgeons Excavation LLC
Rubber Tracked CAT 305 CR Mini-ExcavatorGNP = Granular and Nonplastic
Note: The stratification lines represent approximate
boundaries between soil types. Actual boundaries
may be gradual or transitional.
December 21, 2023 23-230-001
Figure No.8
SheetGRAPHICLOGSOIL DESCRIPTION
SURFACE:Cut Farm Field
SURFACE ELEVATION:Not Measured
DEPTH (FT)GROUNDWATERSAMPLEDEPTH (FT)MOISTURE CONTENT
0 10 20 30 40 50
= MOISTURE CONTENT
1 of 1
0
1.5
3
4.5
6
7.5
9
10.5
TOPSOIL: Lean CLAY, appears firm, black, moist, organics
Lean CLAY, appears soft, light tan, moist, trace sand
Well-Graded GRAVEL with Sand, appears dense, dark
brown, moist to wet, 8-inch minus cobbles
Bottom of Test Pit
1.4
3.6
8.0
G
G
LEGEND LOG OF TEST PIT TP-8Atterberg Limits
Field Moisture content North Park Public Infrastructure
Bozeman, MontanaGroundwater Level
Grab/composite sample
Logged by:Nic Couch, EI
Excavated by:Earth Surgeons Excavation LLC
Rubber Tracked CAT 305 CR Mini-ExcavatorGNP = Granular and Nonplastic
Note: The stratification lines represent approximate
boundaries between soil types. Actual boundaries
may be gradual or transitional.
December 21, 2023 23-230-001
Figure No.9
SheetGRAPHICLOGSOIL DESCRIPTION
SURFACE:Cut Farm Field
SURFACE ELEVATION:Not Measured
DEPTH (FT)GROUNDWATERSAMPLEDEPTH (FT)MOISTURE CONTENT
0 10 20 30 40 50
= MOISTURE CONTENT
1 of 1
Tested By: BC Checked By:
Particle Size Distribution Report
ASTM C117 & C136
PERCENT FINER0
10
20
30
40
50
60
70
80
90
100
GRAIN SIZE - mm.
0.00010.0010.010.1110100
% +3"Coarse
% Gravel
Fine Coarse Medium
% Sand
Fine Silt
% Fines
Clay
0.0 0.0 0.4 0.3 1.1 7.7 90.56 in.3 in.2 in.1½ in.1 in.¾ in.½ in.3/8 in.#4#10#20#30#40#60#100#140#200Test Results (ASTM C117 & C136)Material Description
Atterberg Limits
Coefficients
Classification
Test Remarks
Sample Date:Location: TP-1
Sample Number: A-29311 Depth: 0.9 - 2.0 ft
Client:
Project:
Project No:Figure
Sieve Size
or
Diam. (mm.)
Finer
(%)
Spec.*
(%)
Out of
Spec.
(%)
Pct.
of
Fines
Lean CLAY
3/8"
#4
#10
#20
#40
#60
#80
#100
#200
100.0
99.6
99.3
98.8
98.2
97.2
96.2
95.5
90.5
18 37 19
CL A-6(17)
Report No. A-29311-206
Report Date: 1-23-2024
F.M.=0.10
12-21-2023
Bozeman TRAX Partners LLC
North Park Public Infrastructure
Bozeman, Montana
23-230-001
PL= LL= PI=
D90= D85= D60=
D50= D30= D15=
D10= Cu= Cc=
USCS= AASHTO=
*(no specification provided)
10
Tested By: JB/BC Checked By:
Particle Size Distribution Report
ASTM C117 & C136
PERCENT FINER0
10
20
30
40
50
60
70
80
90
100
GRAIN SIZE - mm.
0.00010.0010.010.1110100
% +3"Coarse
% Gravel
Fine Coarse Medium
% Sand
Fine Silt
% Fines
Clay
9.8 35.7 21.8 6.9 9.5 4.3 12.06 in.3 in.2 in.1½ in.1 in.¾ in.½ in.3/8 in.#4#10#20#30#40#60#100#140#200Test Results (ASTM C117 & C136)Material Description
Atterberg Limits
Coefficients
Classification
Test Remarks
Sample Date:Location: TP-1
Sample Number: A-29313 Depth: 4.0 - 6.0 ft
Client:
Project:
Project No:Figure
Sieve Size
or
Diam. (mm.)
Finer
(%)
Spec.*
(%)
Out of
Spec.
(%)
Pct.
of
Fines
Clayey GRAVEL with Sand
6 6"
3"
1.5"
1"
3/4"
1/2"
3/8"
#4
#10
#20
#40
#60
#80
#100
#200
100.0
90.2
74.1
62.3
54.5
45.3
40.8
32.7
25.8
20.8
16.3
14.2
13.4
13.0
12.0
79.1
63.6
49.8
43.5
41.0
39.8
36.8
Not Tested Not Tested Not Tested
75.4200 59.2472 23.3849
15.8531 3.5200 0.3169
GC
Report No. A-29313-206
Report Date: 1-23-2024
F.M.=6.12
12-21-2023
Bozeman TRAX Partners LLC
North Park Public Infrastructure
Bozeman, Montana
23-230-001
PL= LL= PI=
D90= D85= D60=
D50= D30= D15=
D10= Cu= Cc=
USCS= AASHTO=
*(no specification provided)
11
Tested By: BC Checked By:
Particle Size Distribution Report
ASTM C117 & C136
PERCENT FINER0
10
20
30
40
50
60
70
80
90
100
GRAIN SIZE - mm.
0.00010.0010.010.1110100
% +3"Coarse
% Gravel
Fine Coarse Medium
% Sand
Fine Silt
% Fines
Clay
0.0 15.3 7.0 0.8 2.6 9.7 64.66 in.3 in.2 in.1½ in.1 in.¾ in.½ in.3/8 in.#4#10#20#30#40#60#100#140#200Test Results (ASTM C117 & C136)Material Description
Atterberg Limits
Coefficients
Classification
Test Remarks
Sample Date:Location: TP-4
Sample Number: A-29319 Depth: 1.5 - 2.0 ft
Client:
Project:
Project No:Figure
Sieve Size
or
Diam. (mm.)
Finer
(%)
Spec.*
(%)
Out of
Spec.
(%)
Pct.
of
Fines
Gravelly Lean CLAY
1"
3/4"
1/2"
3/8"
#4
#10
#20
#40
#60
#80
#100
#200
100.0
84.7
79.3
78.7
77.7
76.9
76.0
74.3
72.7
71.3
70.2
64.6
20 35 15
21.3782 19.2213
CL A-6(8)
Report No. A-29319-206
Report Date: 1-23-2024
F.M.=1.87
12-21-2023
Bozeman TRAX Partners LLC
North Park Public Infrastructure
Bozeman, Montana
23-230-001
PL= LL= PI=
D90= D85= D60=
D50= D30= D15=
D10= Cu= Cc=
USCS= AASHTO=
*(no specification provided)
12
Tested By: BC Checked By:
Particle Size Distribution Report
ASTM C117 & C136
PERCENT FINER0
10
20
30
40
50
60
70
80
90
100
GRAIN SIZE - mm.
0.00010.0010.010.1110100
% +3"Coarse
% Gravel
Fine Coarse Medium
% Sand
Fine Silt
% Fines
Clay
0.0 0.0 1.2 0.4 2.3 17.8 78.36 in.3 in.2 in.1½ in.1 in.¾ in.½ in.3/8 in.#4#10#20#30#40#60#100#140#200Test Results (ASTM C117 & C136)Material Description
Atterberg Limits
Coefficients
Classification
Test Remarks
Sample Date:Location: TP-5
Sample Number: A-29321 Depth: 1.5 - 3.5 ft
Client:
Project:
Project No:Figure
Sieve Size
or
Diam. (mm.)
Finer
(%)
Spec.*
(%)
Out of
Spec.
(%)
Pct.
of
Fines
Lean CLAY with Sand
3/8"
#4
#10
#20
#40
#60
#80
#100
#200
100.0
98.8
98.4
97.6
96.1
93.6
90.6
88.1
78.3
20 35 15
0.1709 0.1200
CL A-6(11)
Report No. A-29321-206
Report Date: 1-23-2024
F.M.=0.25
12-21-2023
Bozeman TRAX Partners LLC
North Park Public Infrastructure
Bozeman, Montana
23-230-001
PL= LL= PI=
D90= D85= D60=
D50= D30= D15=
D10= Cu= Cc=
USCS= AASHTO=
*(no specification provided)
13
Tested By: BC/WJC Checked By:
Particle Size Distribution Report
ASTM C117 & C136
PERCENT FINER0
10
20
30
40
50
60
70
80
90
100
GRAIN SIZE - mm.
0.00010.0010.010.1110100
% +3"Coarse
% Gravel
Fine Coarse Medium
% Sand
Fine Silt
% Fines
Clay
5.9 40.6 20.2 5.3 14.4 9.7 3.96 in.3 in.2 in.1½ in.1 in.¾ in.½ in.3/8 in.#4#10#20#30#40#60#100#140#200Test Results (ASTM C117 & C136)Material Description
Atterberg Limits
Coefficients
Classification
Test Remarks
Sample Date:Location: TP-6
Sample Number: A-29324 Depth: 6.8 - 8.5 ft
Client:
Project:
Project No:Figure
Sieve Size
or
Diam. (mm.)
Finer
(%)
Spec.*
(%)
Out of
Spec.
(%)
Pct.
of
Fines
Well-Graded GRAVEL with Sand
6"
3"
1.5"
1"
3/4"
1/2"
#4
#10
#20
#40
#60
#80
#100
#200
100.0
94.1
74.6
62.2
53.5
44.3
33.3
28.0
22.5
13.6
8.2
6.1
5.2
3.9
84.2
67.7
40.9
24.6
18.3
15.6
11.7
Not Tested Not Tested Not Tested
63.5299 53.3647 23.6527
16.6056 2.8604 0.4759
0.3051 77.53 1.13
GW
Report No. A-29324-206
Report Date: 1-23-2024
F.M.=6.17
12-21-2023
Bozeman TRAX Partners LLC
North Park Public Infrastructure
Bozeman, Montana
23-230-001
PL= LL= PI=
D90= D85= D60=
D50= D30= D15=
D10= Cu= Cc=
USCS= AASHTO=
*(no specification provided)
14
Tested By: BS/BC Checked By:
Particle Size Distribution Report
ASTM C117 & C136
PERCENT FINER0
10
20
30
40
50
60
70
80
90
100
GRAIN SIZE - mm.
0.00010.0010.010.1110100
% +3"Coarse
% Gravel
Fine Coarse Medium
% Sand
Fine Silt
% Fines
Clay
0.0 0.0 0.1 0.0 0.4 3.4 96.16 in.3 in.2 in.1½ in.1 in.¾ in.½ in.3/8 in.#4#10#20#30#40#60#100#140#200Test Results (ASTM C117 & C136)Material Description
Atterberg Limits
Coefficients
Classification
Test Remarks
Sample Date:Location: TP-7
Sample Number: A-29326 Depth: 1.5 - 3.5 ft
Client:
Project:
Project No:Figure
Sieve Size
or
Diam. (mm.)
Finer
(%)
Spec.*
(%)
Out of
Spec.
(%)
Pct.
of
Fines
Lean CLAY
1/2"
3/8"
#4
#10
#20
#40
#60
#80
#100
#200
100.0
100.0
99.9
99.9
99.8
99.5
99.1
98.8
98.5
96.1
99.9
99.8
99.5
99.2
98.9
98.6
96.1
20 39 19
CL A-6(19)
Report No. A-29326-206
Report Date: 1-23-2024
F.M.=0.03
12-21-2023
Bozeman TRAX Partners LLC
North Park Public Infrastructure
Bozeman, Montana
23-230-001
PL= LL= PI=
D90= D85= D60=
D50= D30= D15=
D10= Cu= Cc=
USCS= AASHTO=
*(no specification provided)
15
Tested By: BC Checked By:
LIQUID AND PLASTIC LIMITS TEST REPORT
PLASTICITY INDEX0
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
WATER CONTENT35.5
36
36.5
37
37.5
38
38.5
39
39.5
40
40.5
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: TP-1
Sample Number: A-29311 Depth: 0.9 - 2.0 ft
Figure
Lean CLAY 37 18 19 98.2 90.5 CL
23-230-001 Bozeman TRAX Partners LLC
16
Report No. A-29311-207
Report Date: 1-21-2024North Park Public Infrastructure
Bozeman, Montana
Tested By: BC Checked By:
LIQUID AND PLASTIC LIMITS TEST REPORT
PLASTICITY INDEX0
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
WATER CONTENT32.8
33.3
33.8
34.3
34.8
35.3
35.8
36.3
36.8
37.3
37.8
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: TP-4
Sample Number: A-29319 Depth: 1.5 - 2.0 ft
Figure
Gravelly Lean CLAY 35 20 15 74.3 64.6 CL
23-230-001 Bozeman TRAX Partners LLC
17
Report No. A-29319-207
Report Date: 1-21-2024North Park Public Infrastructure
Bozeman, Montana
Tested By: BC Checked By:
LIQUID AND PLASTIC LIMITS TEST REPORT
PLASTICITY INDEX0
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
WATER CONTENT33.2
33.6
34
34.4
34.8
35.2
35.6
36
36.4
36.8
37.2
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: TP-5
Sample Number: A-29321 Depth: 1.5 - 3.5 ft
Figure
Lean CLAY with Sand 35 20 15 96.1 78.3 CL
23-230-001 Bozeman TRAX Partners LLC
18
Report No. A-29321-207
Report Date: 1-21-2024North Park Public Infrastructure
Bozeman, Montana
Tested By: BC Checked By:
LIQUID AND PLASTIC LIMITS TEST REPORT
PLASTICITY INDEX0
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
WATER CONTENT38
38.4
38.8
39.2
39.6
40
40.4
40.8
41.2
41.6
42
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: TP-7
Sample Number: A-29326 Depth: 1.5 - 3.5 ft
Figure
Lean CLAY 39 20 19 99.5 96.1 CL
23-230-001 Bozeman TRAX Partners LLC
19
Report No. A-29326-207
Report Date: 1-21-2024North Park Public Infrastructure
Bozeman, Montana
Tested By: BS Checked By:
Moisture-Density Test Report for Curve No. A-29326
Dry density, pcf85
90
95
100
105
110
Water content, %
12.5 15 17.5 20 22.5 25 27.5
18.3%, 103.7 pcf
ZAV for
Sp.G. =
2.65
Test specification:ASTM D 698-12 Method A Standard
1.5 - 3.5 ft CL A-6(19) 2.65 39 19 0.1 96.1
Lean CLAY
23-230-001 Bozeman TRAX Partners LLC
Report No. A-29326-204
Report Date: 1-21-20241-18-2024
20
Elev/ Classification Nat.Sp.G. LL PI
% > % <
Depth USCS AASHTO Moist.#4 No.200
TEST RESULTS MATERIAL DESCRIPTION
Project No. Client:Remarks:
Project:
Date:
Location: TP-7 Sample Number: A-29326
Figure
Maximum dry density = 103.7 pcf
Optimum moisture = 18.3 %
North Park Public Infrastructure
Bozeman, Montana
Tested By: CRN Checked By:
BEARING RATIO TEST REPORT
ASTM D1883-21
Project No: 23-230-001
Project:North Park Public Infrastructure
Location: TP-7
Sample Number: A-29326 Depth: 1.5 - 3.5 ft
Date: 12-21-2023
Lean CLAY
Test Description/Remarks:
ASTM D698 with 6inch mold
96-hour soak prior to testing
Report No. A-29326-210
Report Date: 1-29-2024
Figure 21
103.7 18.3 39 19CL
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 91.0 87.8 18.9 91.0 87.8 26.7 2.3 1.9 0.000 10
2 99.9 96.3 19.0 99.0 95.4 22.4 5.3 5.4 0.000 10 0.9
3 106.3 102.5 18.7 105.2 101.4 20.1 5.7 7.2 0.000 10 1.1Penetration Resistance (psi)0
70
140
210
280
350
Penetration Depth (in.)
0 0.1 0.2 0.3 0.4 0.5 Swell (%)0
0.4
0.8
1.2
1.6
2
Elapsed Time (hrs)
0 24 48 72 96CBR (%)1
2.5
4
5.5
7
Molded Density (pcf)
85 90 95 100 105 110
10 blows
20 blows
64 blows
CBR at 95% Max. Density = 5.0%
for 0.10 in. Penetration
5
< 500 ohm-cm 30
500 - 1000 ohm-cm 25
> 1000 - 1500 ohm-cm 22
> 1500 - 2000 ohm-cm 19
> 2000 - 3000 ohm-cm 10
> 3000 - 5000 ohm-cm 5
> 5000 ohm-cm 0
> 100 ppm = positive 8
50 - 100 ppm = trace 3
< 50 ppm = negative 0
> 15% = Wet 5
5 - 15% = Moist 2.5
< 5% = Dry 0
Pipe below the water 5
table at any time
pH 0 - 4 4
pH > 4 - 6 1
pH 6 - 8, with sulfides
and low or negative redox 4
pH > 6 0
positive ( 1 ppm)4
trace ( > 0 and < 1 ppm) 1.5
negative ( 0 ppm) 0
= negative 2
= positive 0 - 100 mv 1
= positive > 100 mv 0
Connected to noble metals 2
(e.g. copper) - yes
Connected to noble metals 0
(e.g. copper) - no
TOTAL POSSIBLE POINTS
Cinders, Mine Waste, Peat Bog,
Landfill, Fly Ash, Coal
RESISTIVITY
CHLORIDES
MOISTURE
CONTENT
GROUND WATER
INFLUENCE
pH
SULFIDE
IONS
REDOX
POTENTIAL
BI-METALLIC
CONSIDERATIONS
Known Corrosive
Environments
POINTS
30
8
5
5
4
4
2
2
60
21
* Soils with Known Corrosive Environments shall be assigned 21 points
or the total of points for Likelihood Factors, whichever is greater.
Likelihood Score Sheet
TABLE 2
– >
– >
MAXIMUM
POSSIBLE
POINTS
LIKELIHOOD FACTOR
6
DIPRA and Corrpro again listened to the needs of utility
operators and recognized the differences between long,
large diameter, straight-run transmission mains and the
more complicated networks of distribution pipelines that
bring water to our neighborhoods and businesses. The result
provides a more practical solution for pipeline networks that
comprise the distribution systems within a utility’s service
area. The use of V-Bio® enhanced polyethylene encasement
in conjunction with metallized zinc provides water operators
with an effective alternative to controlling corrosion in
distribution systems.
3” to 24” 0
30” to 36” 8
42” to 48” 12
54” to 64” 22
Routine (Fair to good access,
minimal traffic/other utility 0
consideration, etc.)
Moderate (Typical business/
residential areas, some right 8
of way limitations, etc.)
Difficult (Subaqueous
crossings, downtown
metropolitan business areas, 20 multiple utilities congestion,
swamps, etc.)
0 to 10 feet depth 0
> 10 to 20 feet depth 3
> 20 feet depth 5
Alternate supply available - no 3
Alternate supply available - yes 0
TOTAL POSSIBLE POINTS
PIPE SERVICE
LOCATION:
Construction-Repair
Considerations
DEPTH OF COVER
CONSIDERATIONS
ALTERNATE WATER SUPPLY
POINTS
22
20
5
3
50
Consequence Score Sheet
TABLE 3
The revised
DDM® recognizes
the practical
differences in
corrosion control
needs between
transmission mains
and distribution
systems.
MAXIMUM
POSSIBLE
POINTS
CONSEQUENCE FACTOR
1315 Cherry, Helena, MT 59601
(406)449-6282
SOIL ANALYSIS
Client:TD&H Engineering Date Reported:19-Jan-24
Sample ID:23-230 TP-2 (2.5-3.9 Ft)
Project ID:23-230-001 Chain of Custody #:0027
Site ID:North Park Public Infrastructure
Laboratory ID:06A155 Date / Time Sampled:21-Dec-24
Sample Matrix:Soil Date / Time Received:09-Jan-24 @ 09:30
Analytical Method
Parameter Result Date/Time By Reference
pH, s.u.8.4 10-Jan-24 @ 16:30 CE MT 232-04
Resistivity, ohm/cm 9950 11-Jan-24 @ 13:48 CE MT 232-16
Chloride, mg/Kg 3.11 12-Jan-24 @ 13:34 CE MT 532-16
Redox Potential, mV 261 17-Jan-24 @ 09:35 CE ASTM G22-20
Sulfides, mg/Kg <5.0 19-Jan-24 @ 10:15 CE EPA 376.1
Comments:
Results are As Delivered
References:
Methods for Chemical Analysis of Water and Wastes, US EPA, 600/4-79-020, March 1983.
USDA Handbook 60
Method of Sampling and Testing MT232-04, Soil Corrosion Test (Montana Method).
Method 43 - 4 : ASA Monograph 9 Part1
Reviewed by:
Analyzed
Page 2 of 6
1315 Cherry, Helena, MT 59601
(406)449-6282
SOIL ANALYSIS
Client:TD&H Engineering Date Reported:19-Jan-24
Sample ID:23-230 TP-7 (1.5-3.5 FT)
Project ID:23-230-001 Chain of Custody #:0027
Site ID:North Park Public Infrastructure
Laboratory ID:06A156 Date / Time Sampled:21-Dec-24
Sample Matrix:Soil Date / Time Received:09-Jan-24 @ 09:30
Analytical Method
Parameter Result Date/Time By Reference
pH, s.u.8.5 10-Jan-24 @ 16:30 CE MT 232-04
Resistivity, ohm/cm 9790 11-Jan-24 @ 13:48 CE MT 232-16
Chloride, mg/Kg 6.69 12-Jan-24 @ 14:28 CE MT 532-16
Redox Potential, mV 300 17-Jan-24 @ 09:35 CE ASTM G22-20
Sulfides, mg/Kg <5.0 19-Jan-24 @ 10:15 CE EPA 376.1
Comments:
Results are As Delivered
References:
Methods for Chemical Analysis of Water and Wastes, US EPA, 600/4-79-020, March 1983.
USDA Handbook 60
Method of Sampling and Testing MT232-04, Soil Corrosion Test (Montana Method).
Method 43 - 4 : ASA Monograph 9 Part1
Reviewed by:
Analyzed
Page 3 of 6
1315 Cherry, Helena, MT 59601
(406)449-6282
SOIL ANALYSIS
Client:TD&H Engineering Date Reported:19-Jan-24
Sample ID:23-230 TP-7 (1.5-3.5 FT)
Project ID:23-230-001 Chain of Custody #:0027
Site ID:North Park Public Infrastructure
Laboratory ID:06A157 Date / Time Sampled:21-Dec-24
Sample Matrix:Soil Date / Time Received:09-Jan-24 @ 09:30
Analytical Method
Parameter Result Date/Time By Reference
pH, s.u.8.4 10-Jan-24 @ 16:30 CE MT 232-04
Resistivity, ohm/cm 5950 11-Jan-24 @ 13:48 CE MT 232-16
Chloride, mg/Kg 47.8 12-Jan-24 @ 14:55 CE MT 532-16
Redox Potential, mV 223 17-Jan-24 @ 09:35 CE ASTM G22-20
Sulfides, mg/Kg <5.0 19-Jan-24 @ 10:15 CE EPA 376.1
Comments:
Results are As Delivered
References:
Methods for Chemical Analysis of Water and Wastes, US EPA, 600/4-79-020, March 1983.
USDA Handbook 60
Method of Sampling and Testing MT232-04, Soil Corrosion Test (Montana Method).
Method 43 - 4 : ASA Monograph 9 Part1
Reviewed by:
Analyzed
Page 4 of 6
1315 Cherry, Helena, MT 59601
(406)449-6282
SOIL ANALYSIS
Client:TD&H Engineering Date Reported:19-Jan-24
Sample ID:23-230 TP-7 (5.0-7.0 FT)
Project ID:23-230-001 Chain of Custody #:0027
Site ID:North Park Public Infrastructure
Laboratory ID:06A158 Date / Time Sampled:21-Dec-24
Sample Matrix:Soil Date / Time Received:09-Jan-24 @ 09:30
Analytical Method
Parameter Result Date/Time By Reference
pH, s.u.8.4 10-Jan-24 @ 16:30 CE MT 232-04
Resistivity, ohm/cm 11500 11-Jan-24 @ 13:48 CE MT 232-16
Chloride, mg/Kg 7.86 12-Jan-24 @ 15:22 CE MT 532-16
Redox Potential, mV 264 17-Jan-24 @ 09:35 CE ASTM G22-20
Sulfides, mg/Kg <5.0 19-Jan-24 @ 10:15 CE EPA 376.1
Comments:
Results are As Delivered
References:
Methods for Chemical Analysis of Water and Wastes, US EPA, 600/4-79-020, March 1983.
USDA Handbook 60
Method of Sampling and Testing MT232-04, Soil Corrosion Test (Montana Method).
Method 43 - 4 : ASA Monograph 9 Part1
Reviewed by:
Analyzed
Page 5 of 6
1/23/24, 10:54 AM LTPPBind Online
about:blank 1/2
General Project Information
Project Number: 23-230-001
Project Title: North Park Public Infrastructure
Project Description:
Climatic Data Source (MERRA)
Latitude, Degree: 45.7098
Longitude, Degree: -111.05717
Climatic Data
Lowest Yearly Air Temperature, ºC: -40.90
Low Air Temp Standard Deviation, ºC: 5.19
Yearly Degree-Days > 10 Deg. ºC: 1656.66
High Air Temperature of high 7 days: 28.91
Standard Dev. of the high 7 days: 2.01
Low Pavement Temperature 50%: -30.50
Low Pavement Temperature 98%: -39.30
High Avg Pavement Temperature of 7 Days 50%: 50.90
High Avg Pavement Temperature of 7 Days 98%: 55.06
Target Rut Depth
Target Rut Depth (mm): 16.5
Temperature Adjustments
Depth of Layer, mm: 0
Base HT PG: 52
Traffic Adjustments
Traffic loading Cumulative ESAL for the Design Period, Millions: 0.1
Traffic Speed (Fast: >70 km/h, Slow: 20-70 km/h, Standing: < 20 km/h): Standing
Performance Grade
AASHTO M320-10 Performance-Graded Asphalt Binder
PG Temperature High Low
Performance Grade Temperature at 50% Reliability 35.8 -30.6
Performance Grade Temperature at 98% Reliability 39.8 -39.4
Adjustment for Traffic (AASHTO M323-13)2.8
Adjustment for Depth 0.0 -0.0
Adjusted Performance Grade Temperature 42.6 -39.4
Selected PG Grade 52 -40
PG Grade M323, PG 52-40