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Appendix A
STORMWATER BASINS
EXHIBIT A-1
NORTH
30 15 0
SCALE:1" = 30'
30 60
SIGN
EXISTING SANITARY SEWER
POWER POLE
FLOW ARROW
FIRE HYDRANT
DESIGN POINT (SEE APPENDIX B)
EXISTING OVERHEAD POWER LINE
TYPICAL
SANITARY SEWER MANHOLE
TELEPHONE PEDESTAL
EXISTING WATER
EXISTING CONTOURS
PROPOSED WATER
PROPOSED SANITARY SEWER
PROPOSED POWER
PROPOSED GAS
PROPOSED STORM DRAIN
LEGEND
EXHIBIT A-2
NORTH
30 15 0
SCALE:1" = 30'
30 60
SIGN
EXISTING SANITARY SEWER
POWER POLE
FLOW ARROW
FIRE HYDRANT
DESIGN POINT (SEE APPENDIX B)
EXISTING OVERHEAD POWER LINE
TYPICAL
SANITARY SEWER MANHOLE
TELEPHONE PEDESTAL
EXISTING WATER
EXISTING CONTOURS
PROPOSED WATER
PROPOSED SANITARY SEWER
PROPOSED POWER
PROPOSED GAS
PROPOSED STORM DRAIN
LEGEND
12"
Appendix B
PRE-DEVELOPMENT CALCULATIONS
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140
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(J) w r-=i 100 z ~
z
~ ~ a:
80 r-z w u z 0 u
~ 0
60 ~ ~
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0
Pre-Development
Appendix C
POST DEVELOPMENT CALCULATIONS
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FIGURE 1-1 TIME OF CONCENTRATION (Rational Formula)
140
120
(J) w r-=i 100 z ~
z
~ ~ a:
80 r-z w u z 0 u
~ 0
60 ~ ~
Cl ~ ...J a: w > 40 0
20
0
Post
Development
Basin 2
Project: Industry-Bozeman
Basin Description: Basin 2
Contour Contour Depth Incremental Cumulative
Elevation Area (ft) Volume Volume
(sq. ft) Avg. End Avg. End
(cu. ft) (cu. ft)
4,864.10 922 N/A N/A 0.00
4,864.20 979 0.10 95.03 95.03
4,864.30 1,037 0.10 100.78 195.82
4,864.40 1,097 0.10 106.69 302.51
4,864.50 1,158 0.10 112.77 415.28
4,864.60 1,222 0.10 119.01 534.28
4,864.70 1,287 0.10 125.41 659.69
4,864.80 1,353 0.10 131.98 791.67
4,864.90 1,421 0.10 138.70 930.37
4,865.00 1,491 0.10 145.60 1075.97
4,865.10 1,562 0.10 152.65 1228.62
4,865.20 1,635 0.10 159.87 1388.50
4,865.30 1,710 0.10 167.26 1555.76
4,865.40 1,786 0.10 174.81 1730.56
4,865.50 1,864 0.10 182.51 1913.08
4,865.60 1,941 0.10 190.27 2103.34
4,865.70 2,019 0.10 198.00 2301.34
4,865.80 2,100 0.10 205.92 2507.26
4,865.90 2,184 0.10 214.20 2721.46
4,866.00 2,278 0.10 223.11 2944.57
4,866.10 2,374 0.10 232.60 3177.17
Stage Storage
4,866.10 0 0.00 0.00 3177.17
4,866.20 2,472 0.10 123.59 3300.75
Sub-Basin Area (SF)Area (AC)C Coefficient C*Area Weighted C
Basin 1 174,240 4.00 0.80
Landscape 32,670 0.75 0.15 0.11
Impervious 141,570 3.25 0.95 3.09
Basin 2 43,560 1.00 0.64
Landscape 16,741 0.38 0.15 0.06
Impervious 26819 0.62 0.95 0.58
Design Point 1 - Access Culvert 28,852 0.66 0.64
Landscape 11,008 0.25 0.15 0.04
Impervious 17,844 0.41 0.95 0.39
Design Point 2 - Inlet & Storm Pipe A 159,141 3.65 0.86
Landscape 17,571 0.40 0.15 0.06
Impervious 141,570 3.25 0.95 3.09
Design Point 3 -Inlet & Storm Pipe B 62,131 1.43 0.88
Landscape 5,379 0.12 0.15 0.02
Impervious 56,752 1.30 0.95 1.24
Design Point 4 - NW Roof Drain Pipe C 6,122 0.14 0.95
Landscape 0 0.00 0.15 0.00
Impervious 6,122 0.14 0.95 0.13
Design Point 5 - SW Roof & Patio Drain Pipe D 10,377 0.24 0.95
Landscape 0 0.00 0.15 0.00
Impervious 10,377 0.24 0.95 0.23
Design Point 6 - SE Swale 0.69 0.62
Landscape 12,380 0.28 0.15 0.04
Impervious 17,844 0.41 0.95 0.39
Sub-Basin Runoff Coefficient Worksheet
A 0.86 5.00 3.830 3.653 12.06 259 0.0150 24 27.78 8.84 43%0.52 0.82 12.54 7.23
B 0.88 5.00 3.830 1.426 4.81 186 0.0150 24 27.78 8.84 17%0.33 0.64 7.97 5.62
C 0.95 5.00 3.830 0.141 0.51 200 0.0100 8 1.21 3.47 42%0.51 0.81 4.12 2.82
D 0.95 5.00 3.830 0.238 0.87 150 0.0100 8 1.21 3.47 72%0.70 0.95 5.63 3.30
min 2.5 ft/sec Max 0.75
Total
Area (A)
(ac)
Q/Qf
(% full)d/D V/Vf
Pipe Sizing Worksheet 25-YR, 24-HR Event
Pipe #Weighted
C
Estimated
TOC (Min)
INT*, i
(in/hr)
V Actual
Velocity
(ft/sec)
Q FLOW
(CiA)
(cfs)
Pipe
Length (ft)
Pipe Slope
(ft/ft)
Pipe
Size (in)dQf Flow Full
Capacity (cfs)
Vf Flow Full
Velocity (ft/sec)
3.0
Culvert Report
Hydraflow Express Extension for Autodesk® Civil 3D® by Autodesk, Inc.Tuesday, Jul 13 2021
Design Point 1 - Road Access Culvert
Invert Elev Dn (ft) = 4868.33
Pipe Length (ft) = 35.00
Slope (%) = 0.54
Invert Elev Up (ft) = 4868.52
Rise (in) = 12.0
Shape = Circular
Span (in) = 12.0
No. Barrels = 1
n-Value = 0.012
Culvert Type = Circular Concrete
Culvert Entrance = Square edge w/headwall (C)
Coeff. K,M,c,Y,k = 0.0098, 2, 0.0398, 0.67, 0.5
Embankment
Top Elevation (ft) = 4870.52
Top Width (ft) = 25.00
Crest Width (ft) = 25.00
Calculations
Qmin (cfs) = 0.10
Qmax (cfs) = 1.10
Tailwater Elev (ft) = (dc+D)/2
Highlighted
Qtotal (cfs) = 1.00
Qpipe (cfs) = 1.00
Qovertop (cfs) = 0.00
Veloc Dn (ft/s) = 1.68
Veloc Up (ft/s) = 3.20
HGL Dn (ft) = 4869.04
HGL Up (ft) = 4868.94
Hw Elev (ft) = 4869.11
Hw/D (ft) = 0.59
Flow Regime = Inlet Control
Channel Report
Hydraflow Express Extension for Autodesk® Civil 3D® by Autodesk, Inc.Tuesday, Jul 13 2021
DESIGN POINT 2 - SWALE
Triangular
Side Slopes (z:1) = 4.00, 4.00
Total Depth (ft) = 2.30
Invert Elev (ft) = 4866.50
Slope (%) = 3.00
N-Value = 0.050
Calculations
Compute by: Known Q
Known Q (cfs) = 1.00
Highlighted
Depth (ft) = 0.39
Q (cfs) = 1.000
Area (sqft) = 0.61
Velocity (ft/s) = 1.64
Wetted Perim (ft) = 3.22
Crit Depth, Yc (ft) = 0.33
Top Width (ft) = 3.12
EGL (ft) = 0.43
0 2 4 6 8 10 12 14 16 18 20 22 24
Elev (ft)Depth (ft)Section
4866.00 -0.50
4866.50 0.00
4867.00 0.50
4867.50 1.00
4868.00 1.50
4868.50 2.00
4869.00 2.50
Reach (ft)
6
SOUTHEAST
Channel Report
Hydraflow Express Extension for Autodesk® Civil 3D® by Autodesk, Inc.Wednesday, Jul 14 2021
DESIGN POINT 7 - EAST SWALE
Triangular
Side Slopes (z:1) = 4.00, 4.00
Total Depth (ft) = 1.75
Invert Elev (ft) = 4866.50
Slope (%) = 1.00
N-Value = 0.050
Calculations
Compute by: Known Q
Known Q (cfs) = 0.33
Highlighted
Depth (ft) = 0.32
Q (cfs) = 0.330
Area (sqft) = 0.41
Velocity (ft/s) = 0.81
Wetted Perim (ft) = 2.64
Crit Depth, Yc (ft) = 0.22
Top Width (ft) = 2.56
EGL (ft) = 0.33
0 2 4 6 8 10 12 14 16 18
Elev (ft)Depth (ft)Section
4866.00 -0.50
4866.50 0.00
4867.00 0.50
4867.50 1.00
4868.00 1.50
4868.50 2.00
4869.00 2.50
Reach (ft)
Appendix D
GEOTECHNICAL REPORT
REPORT COVER PAGE
Geotechnical Engineering Report
__________________________________________________________________________
Concept Alt 2A
Bozeman, Montana
March 26, 2021
Terracon Project No. 26205063
Prepared for:
Q Factor
Denver, CO
Prepared by:
Terracon Consultants, Inc.
Billings, Montana
Terracon Consultants, Inc. 2110 Overland Avenue, Suite 124 Billings, Montana 59102
P (406) 656 3072 F (406) 656 3578 terracon.com
REPORT COVER LETTER TO SIGNMarch 26, 2021
Q Factor
3001 Brighton Boulevard, Suite 743
Denver, CO 80216
Attn: Mr. Lucas Michieli
P:(303) 669 4041
E:lucas@qfactorsolutions.com
Re: Geotechnical Engineering Report
Concept Alt 2A
Bozeman, Montana
Terracon Project No. 26205063
Dear Mr. Michieli:
We have completed the Geotechnical Engineering services for the above referenced project. This
study was performed in general accordance with Terracon Proposal No. P26205063 revised
February 17, 2021. This report presents the findings of the subsurface exploration and provides
geotechnical recommendations for earthwork and the design and construction of foundation, floor
slabs, and pavements for the proposed project.
We appreciate the opportunity to be of service to you on this project. If you have any questions
concerning this report or if we may be of further service, please contact us.
Sincerely,
Terracon Consultants, Inc.
Travis Goracke, P.E.Gary W. Rome, P.E.
Senior Geotechnical Engineer Senior Project Manager
Responsive ■Resourceful ■Reliable 1
REPORT TOPICS
INTRODUCTION ............................................................................................................. 1
SITE CONDITIONS ......................................................................................................... 1
PROJECT DESCRIPTION .............................................................................................. 2
GEOTECHNICAL CHARACTERIZATION ...................................................................... 3
GEOTECHNICAL OVERVIEW ....................................................................................... 4
EARTHWORK................................................................................................................. 4
SHALLOW FOUNDATIONS ........................................................................................... 8
SEISMIC CONSIDERATIONS ...................................................................................... 10
FLOOR SLABS............................................................................................................. 11
LATERAL EARTH PRESSURES ................................................................................. 12
PAVEMENTS ................................................................................................................ 15
FROST CONSIDERATIONS ......................................................................................... 18
CORROSIVITY.............................................................................................................. 19
GENERAL COMMENTS ............................................................................................... 20
FIGURES ...................................................................................................................... 22
Note: This report was originally delivered in a web-based format.Orange Bold text in the report indicates a referenced
section heading. The PDF version also includes hyperlinks which direct the reader to that section and clicking on the
GeoReport logo will bring you back to this page. For more interactive features, please view your project online at
client.terracon.com.
ATTACHMENTS
EXPLORATION AND TESTING PROCEDURES
PHOTOGRAPHY LOG
SITE LOCATION AND EXPLORATION PLANS
EXPLORATION RESULTS
SUPPORTING INFORMATION
Note: Refer to each individual Attachment for a listing of contents.
Responsive ■Resourceful ■Reliable 1
INTRODUC TION
Geotechnical Engineering Report
Concept Alt 2A
Bozeman, Montana
Terracon Project No. 26205063
March 26, 2021
INTRODUCTION
This report presents the results of our subsurface exploration and geotechnical engineering
services performed for the potential new commercial office building to be located south of the
intersection of West College Street and Professional Drive in Bozeman, Montana. The purpose
of these services is to provide information and geotechnical engineering recommendations
relative to:
■Subsurface soil conditions ■Foundation design and construction
■Groundwater conditions ■Floor slab design and construction
■Site preparation and earthwork ■Seismic site classification per IBC
■Excavation Considerations ■Lateral earth pressures
■Frost Considerations ■Pavement design and construction
The geotechnical engineering Scope of Services for this project included the advancement of 8
test borings to depths ranging from approximately 5.5 to 20.5 feet below existing site grades.
Maps showing the site and boring locations are shown in the Site Location and Exploration
Plan sections, respectively. The results of the laboratory testing performed on soil samples
obtained from the site during the field exploration are included on the boring logs and as separate
graphs in the Exploration Results section.
SITE CONDITIONS
The following description of site conditions is derived from our site visit in association with the
field exploration and our review of publicly available geologic and topographic maps.
Item Description
Project Location
The Project site is located south of the intersection of West College Street
and Professional Drive in Bozeman, Montana.
Approximate Latitude/Longitude 45.6706° N, 111.0692° W
See Site Location
Geotechnical Engineering Report
Concept Alt 2A ■ Bozeman, Montana
March 26, 2021 ■ Terracon Project No. 26205063
Responsive ■Resourceful ■Reliable 2
Item Description
Existing
Improvements
The site is currently an undeveloped greenfield. A paved access road
(Wagon Wheel Park on the provided site drawing) crosses the site from
southwest to northeast.
Current Ground
Cover Undeveloped sparsely to lightly-vegetated greenfield.
Existing Topography
Based on review of Google Earth Imagery, the site gently slopes to the south
with elevations between approximately 4,860 and 4,875 feet above mean
sea level.
Geology Alluvial deposits consisting of a few feet of clay overlying poorly-graded
gravel throughout the depths explored.
PROJECT DESCRIPTION
Our initial understanding of the project was provided in our proposal and was discussed during
project planning. A period of collaboration has transpired since the project was initiated, and our
final understanding of the project conditions is as follows:
Item Description
Information Provided
Preliminary information was provided by Mr. Michieli with Q Factor via
email and telephone correspondence beginning on or around November
20, 2020.
Project Description
Based on the information provided, the project involves a new greenfield
site construction of a new commercial building on a 4.89 acre parcel of
land. Site development will include paved parking and drive lanes and
associated site utility installation.
Proposed Structure
The building will be a two-story, slab-on-grade structure with concrete tilt-
up wall panel and steel frame construction. The building is proposed to
consist of approximately 80,000 square feet within a 50,000 square foot
footprint.
Maximum Loads
Maximum anticipated loading was provided by the project Structural
Engineer and is anticipated as follows:
■Columns: 240 kips
■Walls: 10 kips per linear foot (klf)
■Slabs: 150 pounds per square foot (psf)
Grading/Slopes
Site grading plans were not provided at the time of report preparation;
however, based upon existing site contours, we anticipate cut and/or fills
up to 5 feet will be required to level the proposed building site for
construction.
Geotechnical Engineering Report
Concept Alt 2A ■ Bozeman, Montana
March 26, 2021 ■ Terracon Project No. 26205063
Responsive ■Resourceful ■Reliable 3
Item Description
Pavements
We have considered both rigid (concrete) and flexible (asphalt) pavement
sections. The following traffic loading was provided for pavement
thickness design:
■Autos/light trucks: 2,000 vehicles per day
■Light delivery and trash collection vehicles: 20 vehicles per week
■Tractor-trailer trucks: <1 vehicle per day
The pavement design period is 20 years.
GEOTECHNICAL CHARACTERIZATION
We have developed a general characterization of the subsurface conditions based upon our
review of the subsurface exploration, laboratory data, geologic setting and our understanding of
the project. This characterization, termed GeoModel, forms the basis of our geotechnical
calculations and evaluation of site preparation and foundation options. Conditions encountered at
each exploration point are indicated on the individual logs. The individual logs can be found in the
Exploration Results section and the GeoModel can be found in the Figures section of this report.
Based on the findings of the exploratory borings, subsurface conditions beneath a thin layer of
topsoil or existing fill can be generalized as follows. For a more detailed view of the model layer
depths at each boring location, refer to the GeoModel.
Model Layer Layer Name General Description
1 Clay Lean clay with varying amounts of sand encountered in all borings.
2 Gravel Poorly graded gravel with varying amounts of silt and sand
encountered in all borings.
Groundwater:Groundwater was encountered in borings B-1 through B-6 at depths ranging from
approximately 8 to 9.5 feet below existing grade during the field investigation. Groundwater level
fluctuations occur due to complex hydrogeologic conditions in the area, any existing subdrainage
systems, and seasonal variations in the amount of rainfall/runoff and other factors not evident at the
time the borings were performed. Therefore, groundwater levels during construction or at other times
in the life of the project may be higher or lower than the levels indicated on the boring logs.
Laboratory Testing
Although a sample of the gravel obtained from Boring B-4 at an approximate depth of 6.5 to 8 feet
below existing grade classified as a well-graded gravel with silt and sand (GW-GM) in general
accordance with the Unified Soil Classification System and ASTM D2487, the material visually
classified as a poorly graded gravel with silt and sand. This is due, in part, to the spit spoon ampler
Geotechnical Engineering Report
Concept Alt 2A ■ Bozeman, Montana
March 26, 2021 ■ Terracon Project No. 26205063
Responsive ■Resourceful ■Reliable 4
not being large enough to accommodate the coarse aggregate and cobble encountered in the
gravel layer.
The results of laboratory testing completed for this project can be found in the Exploration
Results section of this report.
GEOTECHNICAL OVERVIEW
Based on the results of our field investigation, laboratory testing program and geotechnical
analyses, development of the site is considered feasible from a geotechnical viewpoint provided
that the conclusions and considerations provided herein are incorporated into the design and
construction of the project.
The building may be constructed on shallow foundations bearing on structural fill and floor slabs-
on-grade bearing on structural fill are considered suitable. Additional foundation and floor slab
information pertaining to the building can be found in the Floor Slabs and Shallow Foundations
sections of this report.
Support of the pavement section on recompacted site soils is recommended. Additional
information pertaining to the design and construction of pavements can be found in the
Pavements section of this report. The General Comments section provides an understanding of
the report limitations.
We have identified the following geotechnical conditions that could impact design and
construction of the proposed project.
Groundwater
Groundwater was measured at depths ranging from about 8 to 9½ feet below existing site grades.
Terracon recommends maintaining a separation of at least 3 feet between the bottom of proposed
below-grade foundations and measured groundwater levels. It is likely that groundwater levels
below this site may rise due to seasonal variations and other factors. Final site grading should
be planned and designed to avoid cuts where shallow groundwater is known to exist, and also in
areas where such grading would create shallow groundwater conditions. If deeper cuts are
unavoidable, installation of a subsurface drainage system may be needed.
EARTHWORK
Earthwork is anticipated to include clearing and grubbing, excavations, and fill placement. The
following sections provide recommendations for use in the preparation of specifications for the
work. Recommendations include critical quality criteria, as necessary, to render the site in the
Geotechnical Engineering Report
Concept Alt 2A ■ Bozeman, Montana
March 26, 2021 ■ Terracon Project No. 26205063
Responsive ■Resourceful ■Reliable 5
state considered in our geotechnical engineering evaluation for foundations, floor slabs, and
pavements.
Site Preparation
Prior to placing fill, existing vegetation and root mat should be removed. Complete stripping of the
topsoil should be performed in the proposed building and parking/driveway areas. Stripped
materials consisting of vegetation and organic materials should be wasted from the site or used
to revegetate landscaped areas after completion of grading operations.
All exposed surfaces should be free of mounds and depressions that could prevent uniform
compaction. Floor slab, and pavement subgrades should be proofrolled with an adequately
loaded vehicle such as a fully-loaded tandem-axle dump truck. The proofrolling should be
performed under the direction of the Geotechnical Engineer. Areas excessively deflecting under
the proofroll should be delineated and subsequently addressed by the Geotechnical Engineer.
Unacceptable areas delineated by the proof-roll should be removed or mitigated in place prior to
placing fill, floor slab concrete, and/or pavements. Such areas should either be removed or
modified by stabilizing with geotextile. Material that is determined to be excessively wet or dry
should be removed, or moisture conditioned and re-compacted.
Fill Material Types
Fill required to achieve design grade should be classified as structural fill and general fill.
Structural fill is material used below, or within 10 feet of structures, pavements, and constructed
slopes. General fill is material used to achieve grade outside of these areas. Earthen materials
used for structural and general fill should meet the following material property requirements:
Soil Type 1 USCS Classification Acceptable Locations for Placement
On-site clays CL, CH
The on-site clay soils are considered acceptable for use
as structural and/or general fill after moisture
conditioning and re-compaction.
On-site granular
GW, GP, GM, GC, SW,
SP, SM, SC and dual
symbols
The on-site granular soils are considered acceptable for
use as structural and/or general fill after moisture
conditioning and re-compaction
Imported soils Varies
Imported soils meeting the gradation outlined herein
can be considered suitable for use as structural and/or
general fill.
1.Structural and general fill should consist of approved materials free of organic matter and debris. Frozen
material should not be used, and fill should not be placed on a frozen subgrade. A sample of each material
type should be submitted to the Geotechnical Engineer for evaluation prior to use on this site.
Imported soils for use as structural and/or general fill should conform to the following:
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Gradation Percent finer by weight (ASTM C136)
3”100
No. 4 Sieve 30-60
No. 200 Sieve 0-25
Soil Properties Value
Liquid Limit 30 (max)
Plastic Index 10 (max)
Fill Compaction Requirements
Structural and general fill should meet the following compaction requirements.
Item Structural Fill
Maximum lift
thickness
8 inches or less in loose thickness when heavy, self-propelled compaction
equipment is used
4 to 6 inches in loose thickness when hand-guided equipment (i.e. jumping
jack, plate compactor) is used
Minimum
compaction
requirements 1, 2, 3
95% of the materials maximum dry density for floor slab subgrade, pavement
subgrade, utility trench and exterior foundation wall backfill
98% of the materials maximum dry density for foundation subgrade
Water content
range 2, 4
Within two percent above optimum water content (cohesive soils)
Within three percent of optimum water content (granular soils)
1.We recommend that engineered fill be tested for water content and compaction during placement. Should
the results of the in-place density tests indicate the specified water or compaction limits have not been met,
the area represented by the test should be reworked and retested as required until the specified water and
compaction requirements are achieved.
2.Maximum dry density and optimum water content as determined by the Standard Proctor test (D698).
3.If the granular material is a coarse sand or gravel, or of a uniform size, or has a low fines content,
compaction comparison to relative density may be more appropriate. In this case, granular materials should
be compacted to at least 70% relative density (ASTM D4253 and D4254).
4.Moisture contents should be maintained low enough to allow for satisfactory compaction to be achieved
without the compacted fill material becoming unstable under the weight of construction equipment or during
proof-rolling. Indications of unstable soil can include pumping or rutting.
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Grading and Drainage
All grades must provide effective drainage away from the building during and after construction
and should be maintained throughout the life of the structure. Water retained next to the building
can result in soil movements greater than those discussed in this report. Greater movements can
result in unacceptable differential floor slab and/or foundation movements, cracked slabs and
walls, and roof leaks. The roof should have gutters/drains with downspouts that discharge onto
splash blocks at a distance of at least 10 feet from the building.
Exposed ground should be sloped and maintained at a minimum 5% away from the building for
at least 10 feet beyond the perimeter of the building. Locally, flatter grades may be necessary to
transition ADA access requirements for flatwork. After building construction and landscaping have
been completed, final grades should be verified to document effective drainage has been
achieved. Grades around the structure should also be periodically inspected and adjusted, as
necessary, as part of the structure’s maintenance program. Where paving or flatwork abuts the
structure, a maintenance program should be established to effectively seal and maintain joints
and prevent surface water infiltration.
Earthwork Construction Considerations
Shallow excavations for the proposed structure are anticipated to be accomplished with
conventional construction equipment. There is a potential for the on-site clay soils to become
unstable, particularly under repetitive construction traffic and/or increases in moisture content.
Stabilization of these soils should be anticipated within portions of the site. Stabilization
techniques can include removal and replacement of the unstable soils, or the use of
geogrids/geotextiles in combination with aggregate base course. The depth of base course will
be dependent on the severity of unstable soils. It has been our experience that between 12 to 24
inches of base course may be required for stabilization.
Upon completion of filling and grading, care should be taken to maintain the subgrade water
content prior to construction of foundations, floor slabs and pavements. Construction traffic over
the completed subgrades should be avoided. The site should also be graded to prevent ponding
of surface water on the prepared subgrades or in excavations. Water collecting over or adjacent
to construction areas should be removed. If the subgrade freezes, desiccates, saturates, or is
disturbed, the affected material should be removed, or the materials should be scarified, moisture
conditioned, and recompacted prior to construction.
The groundwater table could affect overexcavation efforts, especially for deeper utility trench
installation. Depending on site grading and groundwater fluctuations, a temporary dewatering system
consisting of sumps with pumps could be necessary to achieve the recommended depth of
installation.
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As a minimum, excavations should be performed in accordance with OSHA 29 CFR, Part 1926,
Subpart P, “Excavations” and its appendices, and in accordance with any applicable local, and/or
state regulations.
Construction site safety is the sole responsibility of the contractor who controls the means,
methods, and sequencing of construction operations. Under no circumstances shall the
information provided herein be interpreted to mean Terracon is assuming responsibility for
construction site safety, or the contractor's activities; such responsibility shall neither be implied
nor inferred.
Construction Observation and Testing
The earthwork efforts should be monitored under the direction of the Geotechnical Engineer.
Monitoring should include documentation of adequate removal of vegetation and topsoil,
proofrolling, and mitigation of areas delineated by the proofroll to require mitigation.
Each lift of compacted fill should be tested, evaluated, and reworked, as necessary, until approved
by the Geotechnical Engineer prior to placement of additional lifts. In areas of foundation
excavations, the bearing subgrade should be evaluated under the direction of the Geotechnical
Engineer. If unanticipated conditions are encountered, the Geotechnical Engineer should
prescribe mitigation options.
In addition to the documentation of the essential parameters necessary for construction, the
continuation of the Geotechnical Engineer into the construction phase of the project provides the
continuity to maintain the Geotechnical Engineer’s evaluation of subsurface conditions, including
assessing variations and associated design changes.
SHALLOW FOUNDATIONS
If the site has been prepared in accordance with the requirements noted in Earthwork, the
following design parameters are applicable for shallow foundations.
Design Parameters – Compressive Loads
Item Description
Maximum Net Allowable Bearing
pressure 1, 2 5,000 psf
Required Bearing Stratum 3 Undisturbed natural gravel or on a zone of granular
structural fill extending to natural gravel.
Minimum Foundation Dimensions Columns:30 inches
Continuous: 18 inches
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Item Description
Maximum Foundation Dimensions Columns:84 inches
Continuous: 24 inches
Ultimate Passive Resistance 4
(equivalent fluid pressures)See Lateral Earth Pressures
Ultimate Coefficient of Sliding Friction 5 0.50 natural gravel or compacted granular structural fill
Minimum Embedment below
Finished Grade 6
Exterior footings in (un)heated areas: 42 inches
Interior footings in heated areas:24 inches
Estimated Total Settlement from
Structural Loads 2 Less than about ¾ inch
Estimated Differential Settlement 2, 7 About ½ to ¾ of total settlement
1.The maximum net allowable bearing pressure is the pressure in excess of the minimum surrounding
overburden pressure at the footing base elevation. An appropriate factor of safety has been applied. These
bearing pressures can be increased by 1/3 for transient loads unless those loads have been factored to
account for transient conditions. Values assume that exterior grades are no steeper than 20% within 10
feet of structure.
2.Values provided are for maximum loads noted in Project Description. The foundation movement will
depend upon the variations within the subsurface soil profile, the structural loading conditions, the
embedment depth of the footings, the thickness of compacted fill, the quality of the earthwork operations,
and maintaining uniform soil water content throughout the life of the structure. The estimated movements
are based on maintaining uniform soil water content during the life of the structure. Additional foundation
movements could occur if water from any source infiltrates the foundation soils; therefore, proper drainage
and irrigation practices should be incorporated into the design and operation of the facility. Failure to
maintain soil water content and positive drainage will nullify the movement estimates provided above.
3.Unsuitable or soft soils should be over-excavated and replaced per the recommendations presented in the
Earthwork.
4.Use of passive earth pressures require the sides of the excavation for the spread footing foundation to be
nearly vertical and the concrete placed neat against these vertical faces or that the footing forms be
removed and compacted structural fill be placed against the vertical footing face.
5.Can be used to compute sliding resistance where foundations are placed on suitable soil/materials. Should
be neglected for foundations subject to net uplift conditions.
6.Embedment necessary to minimize the effects of frost and/or seasonal water content variations. For sloping
ground, maintain depth below the lowest adjacent exterior grade within 5 horizontal feet of the structure.
7.Differential settlements are as measured over a span of 50 feet.
Foundation Construction Considerations
As noted in Earthwork, the footing excavations should be evaluated under the direction of the
Geotechnical Engineer. The base of all foundation excavations should be free of water and loose
soil, prior to placing concrete. Concrete should be placed soon after excavating to reduce bearing
soil disturbance. Care should be taken to prevent wetting or drying of the bearing materials during
construction. Excessively wet or dry material or any loose/disturbed material in the bottom of the
footing excavations should be removed/reconditioned before foundation concrete is placed.
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If unsuitable bearing soils are encountered at the base of the planned footing excavation, the
excavation should be extended deeper to suitable soils, and the footings could bear directly on
these soils at the lower level or on lean concrete backfill placed in the excavations. This is
illustrated on the sketch below.
Over-excavation for structural fill placement below footings should be conducted as shown below.
The over-excavation should be backfilled up to the footing base elevation, with soil placed as
recommended in the Earthwork section.
SEISMIC CONSIDERATIONS
The seismic design requirements for buildings and other structures are based on Seismic Design
Category. Site Classification is required to determine the Seismic Design Category for a structure.
The Site Classification is based on the upper 100 feet of the site profile defined by a weighted
average value of either shear wave velocity, standard penetration resistance, or undrained shear
strength in accordance with Section 20.4 of ASCE 7 and the International Building Code (IBC).
Based on the soil properties encountered at the site and as described on the exploration logs and
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results, it is our professional opinion that the Seismic Site Classification is C. Subsurface
explorations at this site were extended to a maximum depth of 20.5 feet. The site properties below
the boring depth to 100 feet were estimated based on our experience and knowledge of geologic
conditions of the general area. Additional deeper borings or geophysical testing may be performed
to confirm the conditions below the current boring depth.
FLOOR SLABS
Depending upon the finished floor elevation, unsuitable, weak, medium stiff to very stiff soils may
be encountered at the floor slab subgrade level. These soils should be replaced with structural fill
so the floor slab is supported on at least 1 foot of recompacted suitable natural soils or imported
structural fill.
Design parameters for floor slabs assume the requirements for Earthwork have been followed.
Specific attention should be given to positive drainage away from the structure and positive drainage
of the aggregate base beneath the floor slab.
Floor Slab Design Parameters
Item Description
Floor Slab Support 1 At least 12 inches of structural fill placed in accordance with the Earthwork
section. Compacted structural fill should also extend a minimum of 10 feet
beyond the perimeter of the building.
Estimated Modulus of
Subgrade Reaction 2 175 pounds per square inch per inch (psi/in) for point loads
1.Floor slabs should be structurally independent of building footings or walls to reduce the possibility of floor
slab cracking caused by differential movements between the slab and foundation.
2.Modulus of subgrade reaction is an estimated value based upon our experience with the subgrade
condition, the requirements noted in Earthwork, and the floor slab support as noted in this table. It is
provided for point loads. For large area loads the modulus of subgrade reaction would be lower.
The use of a vapor retarder should be considered beneath concrete slabs on grade covered with
wood, tile, carpet, or other moisture sensitive or impervious coverings, or when the slab will
support equipment sensitive to moisture. When conditions warrant the use of a vapor retarder,
the slab designer should refer to ACI 302 and/or ACI 360 for procedures and cautions regarding
the use and placement of a vapor retarder.
Saw-cut control joints should be placed in the slab to help control the location and extent of
cracking. For additional recommendations refer to the ACI Design Manual. Joints or cracks should
be sealed with a water-proof, non-extruding compressible compound specifically recommended
for heavy duty concrete pavement and wet environments.
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Where floor slabs are tied to perimeter walls or turn-down slabs to meet structural or other
construction objectives, our experience indicates differential movement between the walls and
slabs will likely be observed in adjacent slab expansion joints or floor slab cracks beyond the
length of the structural dowels. The Structural Engineer should account for potential differential
settlement through use of sufficient control joints, appropriate reinforcing or other means.
Floor Slab Construction Considerations
Finished subgrade, within and for at least 10 feet beyond the floor slab, should be protected from
traffic, rutting, or other disturbance and maintained in a relatively moist condition until floor slabs are
constructed. If the subgrade should become damaged or desiccated prior to construction of floor
slabs, the affected material should be removed, and structural fill should be added to replace the
resulting excavation. Final conditioning of the finished subgrade should be performed immediately
prior to placement of the floor slab support course.
The Geotechnical Engineer should approve the condition of the floor slab subgrades immediately
prior to placement of the floor slab support course, reinforcing steel, and concrete. Attention should
be paid to high traffic areas that were rutted and disturbed earlier, and to areas where backfilled
trenches are located.
LATERAL EARTH PRESSURES
Design Parameters
Structures with unbalanced backfill levels on opposite sides should be designed for earth
pressures at least equal to values indicated in the following table. Earth pressures will be
influenced by structural design of the walls, conditions of wall restraint, methods of construction
and/or compaction and the strength of the materials being restrained. Two wall restraint conditions
are shown in the diagram below. Active earth pressure is commonly used for design of free-
standing cantilever retaining walls and assumes wall movement. The “at-rest” condition assumes
no wall movement. The recommended design lateral earth pressures do not include a factor of
safety and do not provide for possible hydrostatic pressure on the walls (unless stated).
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Lateral Earth Pressure Design Parameters
Earth Pressure
Condition 1
Coefficient for
Backfill Type2
Surcharge
Pressure 3, 4, 5
p1 (psf)
Effective Fluid Pressures (psf)2, 4, 5
Unsaturated 6 Submerged 6
Active (Ka)Granular - 0.27
Fine Grained - 0.49
(0.27)S
(0.49)S
(35)H
(60)H
(80)H
(90)H
At-Rest (Ko)Granular - 0.43
Fine Grained - 0.66
(0.43)S
(0.66)S
(55)H
(80)H
(92)H
(100)H
Passive (Kp)Granular - 3.69
Fine Grained - 2.04
---
---
(480)H
(245)H
(313)H
(180)H
1.For active earth pressure, wall must rotate about base, with top lateral movements 0.002 H to 0.004 H,
where H is wall height. For passive earth pressure, wall must move horizontally to mobilize resistance.
2.Uniform, horizontal backfill, compacted to at least 95% of the ASTM D 698 maximum dry density, rendering
an anticipated maximum unit weight of 120 pcf and an internal friction angle of 20° for on site clays;.an
anticipated maximum unit weight of 130 pcf and an internal friction angle of 35° can be used for granular
soils.
3.Uniform surcharge, where S is surcharge pressure.
4.Loading from heavy compaction equipment is not included.
5.No safety factor is included in these values.
6.To achieve “Unsaturated” conditions, follow guidelines in Subsurface Drainage for Below-Grade Walls
below. “Submerged” conditions are recommended when drainage behind walls is not incorporated into the
design.
Backfill placed against structures should consist of granular soils or low plasticity cohesive soils.
For the granular values to be valid, the granular backfill must extend out and up from the base of
the wall at an angle of at least 45 and 60 degrees from vertical for the active and passive cases,
respectively.
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Subsurface Drainage for Below-Grade Walls
A perforated rigid plastic drain line installed behind the base of walls and extends below adjacent
grade is recommended to prevent hydrostatic loading on the walls. The invert of a drain line
around a below-grade building area or exterior retaining wall should be placed near foundation
bearing level. The drain line should be sloped to provide positive gravity drainage to daylight or
to a sump pit and pump. The drain line should be surrounded by clean, free-draining granular
material having less than 5% passing the No. 200 sieve, such as ASTM No. 57 aggregate. The
free-draining aggregate should be encapsulated in a filter fabric. The granular fill should extend
to within 2 feet of final grade, where it should be capped with compacted cohesive fill to reduce
infiltration of surface water into the drain system.
As an alternative to free-draining granular fill, a pre-fabricated drainage structure may be used. A
pre-fabricated drainage structure is a plastic drainage core or mesh which is covered with filter
fabric to prevent soil intrusion and is fastened to the wall prior to placing backfill.
The preceding data are applicable only to cast-in-place concrete or modular block walls up to 5
feet in height.If taller single walls, tiered walls, or Mechanically Stabilized Earth (MSE) walls
will be included in the proposed development, additional site-specific studies and
laboratory testing will be required. In addition, the wall designer should perform standard wall
design practices including analysis for overturning, sliding, bearing capacity, and global stability,
and results of these analyses should be provided for our review. Additional sampling, laboratory
testing and document review associated with retaining walls is beyond the original scope of work
but can be performed as a separate scope, for a separate fee.
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PAVEMENTS
General Pavement Comments
Pavement designs are provided for the traffic conditions and pavement life conditions as noted in
Project Description and in the following sections of this report. A critical aspect of pavement
performance is site preparation. Pavement designs noted in this section must be applied to the
site which has been prepared as recommended in the Earthwork section.
Pavement Design Parameters
A subgrade CBR of 5 was used for the AC pavement designs, and a modulus of subgrade reaction
of 120 pci was used for the PCC pavement designs. The values were based on California Bearing
Ratio (CBR) testing performed on a disturbed bulk composite sample of the clay subgrade
obtained from borings B-7 and B-8 at approximate depths of 1 to 2 feet below existing grade and
our understanding of the quality of the subgrade as prescribed by the Site Preparation conditions
as outlined in Earthwork. A modulus of rupture of 580 psi was used for pavement concrete.
Pavement design recommendations for this project have been based on procedures outlined in
the AASHTO Guide for Design of Pavement Structures, 1993, coupled with publications by the
American Concrete Institute on the design of parking lots and our local experience. Pavement
design input parameters and resulting pavement sections are provided in the following table:
Pavement Thickness Design Parameters
Input Parameter Flexible (asphalt)Rigid (concrete)
Reliability 80 80
Initial Serviceability 4.2 4.5
Terminal Serviceability 2.0 2.5
Standard Deviation 0.45 0.35
Drainage 0.9 0.9
Design ESAL Value: Anticipated Traffic 27,000 Light Duty
110,000 Heavy Duty
27,000 Light Duty
150,000 Heavy Duty
Pavement Section Thicknesses
The following table provides options for AC and PCC Sections:
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Asphaltic Concrete Design
Traffic Area Asphalt Concrete (in.)1 Aggregate Base (in.)2 Total Thickness (in.)1
Light Duty
(passenger car
parking areas)
3 6 9
Heavy Duty
(truck traffic
areas and drives)
4 6 10
1.Asphalt concrete should conform to Montana Public Works Standard Specifications (MPWSS) and the current
City of Bozeman Standard Modifications to MPWSS requirements.
2.Aggregate base should meet the requirements for 1-1/2 inch crushed aggregate in accordance with MPWSS
and the current City of Bozeman Standard Modifications to MPWSS Section 02235.
Portland Cement Concrete Design
Traffic Area Portland Cement
Concrete (in.)1 Aggregate Base (in.)2 Total Thickness (in.)
Light Duty
(passenger car
parking areas)
5 4 9
Heavy Duty (truck
traffic areas and
drives)
6.5 4 10.5
1.Portland cement concrete should conform to MPWSS and the current City of Bozeman Standard Modifications
to MPWSS requirements.
2.Aggregate base should meet the requirements for 1-1/2 inch crushed aggregate in accordance with MPWSS
and the current City of Bozeman Standard Modifications to MPWSS Section 02235
Migration of fines into the aggregate base course layer will reduce the support characteristics of
the base and decrease performance of the pavement section. The placement of a geotextile
separation fabric, such as a Mirafi 140N or equivalent, between the fine-grained subgrade and
the aggregate base course to improve constructability and extend the pavement’s service life
should be considered for the above sections.
Concrete for rigid pavements should have a minimum 28-day compressive strength of 4,000 psi,
and be placed with a maximum slump of 4 inches. Although not required for structural support, a
minimum 4-inch thick base course layer is recommended to help reduce potential for slab curl,
shrinkage cracking, and subgrade pumping through joints. Proper joint spacing will also be
required to prevent excessive slab curling and shrinkage cracking. Joints should be sealed to
prevent entry of foreign material and doweled where necessary for load transfer.
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Where practical, we recommend early-entry cutting of crack-control joints in PCC pavements.
Cutting of the concrete in its “green” state typically reduces the potential for micro-cracking of the
pavements prior to the crack control joints being formed, compared to cutting the joints after the
concrete has fully set. Micro-cracking of pavements may lead to crack formation in locations other
than the sawed joints, and/or reduction of fatigue life of the pavement.
Pavement design methods are intended to provide structural sections with adequate thickness
over a subgrade such that wheel loads are reduced to a level the subgrade can support. The
support characteristics of the subgrade for pavement design do not account for shrink/swell
movements of the subgrade. Thus, the pavement may be adequate from a structural standpoint,
yet still experience cracking and deformation due to shrink/swell related movement of the
subgrade. It is, therefore, important to minimize moisture changes in the subgrade to reduce
shrink/swell movements.
Openings in pavements, such as decorative landscaped areas, are sources for water infiltration
into surrounding pavement systems. Water can collect in the islands and migrate into the
surrounding subgrade soils thereby degrading support of the pavement. This is especially
applicable for islands with raised concrete curbs, irrigated foliage, and low permeability near-
surface soils. The civil design for the pavements with these conditions should include features to
restrict or collect and discharge excess water from the islands. Examples of features are edge
drains connected to the storm water collection system, longitudinal subdrains, or other suitable
outlets and impermeable barriers preventing lateral migration of water such as a cutoff wall
installed to a depth below the pavement structure.
Dishing in parking lots surfaced with ACC is usually observed in frequently-used parking stalls
(such as near the front of buildings), and occurs under the wheel footprint in these stalls. The use
of higher-grade asphaltic cement, or surfacing these areas with PCC, should be considered. The
dishing is exacerbated by factors such as irrigated islands or planter areas, sheet surface
drainage to the front of structures, and placing the ACC directly on a compacted clay subgrade.
Pavement Drainage
Pavements should be sloped to provide rapid drainage of surface water. Water allowed to pond
on or adjacent to the pavements could saturate the subgrade and contribute to premature
pavement deterioration. In addition, the pavement subgrade should be graded to provide positive
drainage within the granular base section. Appropriate sub-drainage or connection to a suitable
daylight outlet should be provided to remove water from the granular subbase.
Pavement Maintenance
The pavement sections represent minimum recommended thicknesses and, as such, periodic
maintenance should be anticipated. Therefore, preventive maintenance should be planned and
provided for through an on-going pavement management program. Maintenance activities are
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intended to slow the rate of pavement deterioration and to preserve the pavement investment.
Maintenance consists of both localized maintenance (e.g., crack and joint sealing and patching)
and global maintenance (e.g., surface sealing). Preventive maintenance is usually the priority
when implementing a pavement maintenance program. Additional engineering observation is
recommended to determine the type and extent of a cost-effective program. Even with periodic
maintenance, some movements and related cracking may still occur and repairs may be required.
Pavement performance is affected by its surroundings. In addition to providing preventive
maintenance, the civil engineer should consider the following recommendations in the design and
layout of pavements:
■Final grade adjacent to paved areas should slope down from the edges at a minimum 2%.
■Subgrade and pavement surfaces should have a minimum 2% slope to promote proper
surface drainage.
■Install below pavement drainage systems surrounding areas anticipated for frequent
wetting.
■Install joint sealant and seal cracks immediately.
■Seal all landscaped areas in or adjacent to pavements to reduce moisture migration to
subgrade soils.
■Place compacted, low permeability backfill against the exterior side of curb and gutter.
■Place curb, gutter and/or sidewalk directly on clay subgrade soils rather than on unbound
granular base course materials.
FROST CONSIDERATIONS
The soils on this site are frost susceptible, and small amounts of water can affect the performance
of the slabs on-grade, sidewalks, and pavements. Exterior slabs should be anticipated to heave
during winter months. If frost action needs to be eliminated in critical areas, we recommend the
use of non-frost susceptible (NFS) fill or structural slabs (for instance, structural stoops in front of
building doors). Placement of NFS material in large areas may not be feasible; however, the
following recommendations are provided to help reduce potential frost heave:
■Provide surface drainage away from the building and slabs, and toward the site storm
drainage system.
■Install drains around the perimeter of the pavements and connect them to the storm
drainage system.
■Grade clayey subgrades, so groundwater potentially perched in overlying more permeable
subgrades, such as sand or aggregate base, slope toward a site drainage system.
■Place NFS fill as backfill beneath slabs and pavements critical to the project.
■Place a 3 horizontal to 1 vertical (3H:1V) transition zone between NFS fill and other soils.
■Place NFS materials in critical sidewalk areas.
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As an alternative to extending NFS fill to the full frost depth, consideration can be made to placing
extruded polystyrene or cellular concrete under a buffer of at least 2 feet of NFS material.
CORROSIVITY
The table below lists the results of laboratory soluble sulfate, soluble chloride, electrical resistivity,
and pH testing. The values may be used to estimate potential corrosive characteristics of the on-
site soils with respect to contact with the various underground materials which will be used for
project construction.
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Corrosivity Test Results Summary
Boring Sample Depth
(feet)
Soil
Description
Soluble
Sulfate (%)
Electrical
Resistivity* (Ω-cm)pH
B-2 0 – 1.5 CL ND**1,870 6.7
*Performed on a saturated soil sample
**ND – not detected at the reporting limit
Results of water-soluble sulfate testing indicate that samples of the on-site soils have an exposure
class of S0 when classified in accordance with Table 19.3.1.1 of the American Concrete Institute
(ACI) Design Manual. The results of the testing indicate ASTM Type I Portland Cement is suitable
for project concrete in contact with on-site soils. However, it has been our experience that clay soils
in the area can have moderate to severe sulfate levels. We recommend the use of ASTM Type I/II
Modified Portland Cement for additional sulfate resistance of construction concrete. Concrete
should be designed in accordance with the provision of the ACI Design Manual, Section 318.
GENERAL COMMENTS
Our analysis and opinions are based upon our understanding of the project, the geotechnical
conditions in the area, and the data obtained from our site exploration. Natural variations will occur
between exploration point locations or due to the modifying effects of construction or weather.
The nature and extent of such variations may not become evident until during or after construction.
Terracon should be retained as the Geotechnical Engineer, where noted in this report, to provide
observation and testing services during pertinent construction phases. If variations appear, we
can provide further evaluation and supplemental recommendations. If variations are noted in the
absence of our observation and testing services on-site, we should be immediately notified so
that we can provide evaluation and supplemental recommendations.
Our Scope of Services does not include either specifically or by implication any environmental or
biological (e.g., mold, fungi, bacteria) assessment of the site or identification or prevention of
pollutants, hazardous materials or conditions. If the owner is concerned about the potential for
such contamination or pollution, other studies should be undertaken.
Our services and any correspondence or collaboration through this system are intended for the
sole benefit and exclusive use of our client for specific application to the project discussed and
are accomplished in accordance with generally accepted geotechnical engineering practices with
no third-party beneficiaries intended. Any third-party access to services or correspondence is
solely for information purposes to support the services provided by Terracon to our client.
Reliance upon the services and any work product is limited to our client, and is not intended for
third parties. Any use or reliance of the provided information by third parties is done solely at their
own risk. No warranties, either express or implied, are intended or made.
Geotechnical Engineering Report
Concept Alt 2A ■ Bozeman, Montana
March 26, 2021 ■ Terracon Project No. 26205063
Responsive ■Resourceful ■Reliable 21
Site characteristics as provided are for design purposes and not to estimate excavation cost. Any
use of our report in that regard is done at the sole risk of the excavating cost estimator as there
may be variations on the site that are not apparent in the data that could significantly impact
excavation cost. Any parties charged with estimating excavation costs should seek their own site
characterization for specific purposes to obtain the specific level of detail necessary for costing.
Site safety, and cost estimating including, excavation support, and dewatering
requirements/design are the responsibility of others. If changes in the nature, design, or location
of the project are planned, our conclusions and recommendations shall not be considered valid
unless we review the changes and either verify or modify our conclusions in writing.
Responsive ■Resourceful ■Reliable
FIGURES
Contents:
GeoModel
0
2
4
6
8
10
12
14
16
18
20
22DEPTH BELOW GRADE (Feet)Concept Alt 2A - Bozeman Bozeman, MTTerracon Project No. 26205063
Layering shown on this figure has been developed by the geotechnical
engineer for purposes of modeling the subsurface conditions asrequired for the subsequent geotechnical engineering for this project.Numbers adjacent to soil column indicate depth below ground surface.
NOTES:
B-1 B-2 B-3 B-4 B-5 B-6 B-7 B-8
GEOMODEL
This is not a cross section. This is intended to display the Geotechnical Model only. See individual logs for more detailed conditions.
Groundwater levels are temporal. The levels shown are representative of the dateand time of our exploration. Significant changes are possible over time.Water levels shown are as measured during and/or after drilling. In some cases,
boring advancement methods mask the presence/absence of groundwater. Seeindividual logs for details.
First Water Observation
LEGEND
Topsoil
Lean Clay with Sand
Poorly-graded Gravel withSilt and Sand
Well-graded Gravel withSand
Poorly-graded Gravel
Model Layer General DescriptionLayer Name
Lean clay with varying amounts of sand.1
Poorly graded gravel with varying amounts of silt and sand.2
Clay
Gravel
2
10.5
1
2
8.5
2
20.5
1
2
9
4.5
10.5
1
2
9
2.5
10.5
1
2
8
4
10.5
1
2
9.5
3
20.5
1
2
9
2.5
5.5
1
2
2
5.5
1
2
Responsive ■Resourceful ■Reliable
ATTACHMENTS
Geotechnical Engineering Report
Concept Alt 2A ■ Bozeman, Montana
March 26, 2021 ■ Terracon Project No. 26205063
Responsive ■Resourceful ■Reliable EXPLORATION AND TESTING PROCEDURES 1 of 2
EXPLORATION AND TESTING PROCEDURES
Field Exploration
Number of Borings Boring Depth (feet)Planned Location
6 10.5 to 20.5 Planned Building Area
2 5.5 Planned Parking Area
Boring Layout and Elevations: The locations of the borings were laid out on site by Terracon
personnel using hand-held GPS equipment (estimated horizontal accuracy of about ±20 feet). No
topographic information was provided to Terracon for interpolation of approximate elevations. If
elevations and a more precise boring layout are desired, we recommend boring locations be
surveyed.
Subsurface Exploration Procedures: We advanced the borings with a truck-mounted rotary drill
rig using continuous-flight, hollow-stem augers. Four samples were obtained in the upper 10 feet
of each boring and at intervals of 5 feet thereafter. In the split-barrel sampling procedure, a standard
2-inch outer diameter split-barrel sampling spoon was driven into the ground by a 140-pound
automatic hammer falling a distance of 30 inches. The number of blows required to advance the
sampling spoon the last 12 inches of a normal 18-inch penetration was recorded as the Standard
Penetration Test (SPT) resistance value. The SPT resistance values, also referred to as N-values,
are indicated on the boring logs at the test depths.
The sampling depths, penetration distances, and other sampling information was recorded on the
field boring logs. The samples were placed in appropriate containers and taken to our soil laboratory
for testing and classification by a Geotechnical Engineer. Our exploration team prepared field
boring logs as part of the drilling operations. These field logs included visual classifications of the
materials encountered during drilling and our interpretation of the subsurface conditions between
samples. Final boring logs were prepared from the field logs. The final boring logs represent the
Geotechnical Engineer's interpretation of the field logs and include modifications based on
observations and tests of the samples in our laboratory.
Laboratory Testing
The project engineer reviewed the field data and assigned laboratory tests to understand the
engineering properties of the various soil strata, as necessary, for this project. The following
testing was performed:
■Moisture content
■Dry unit weight
■Atterberg limits
Geotechnical Engineering Report
Concept Alt 2A ■ Bozeman, Montana
March 26, 2021 ■ Terracon Project No. 26205063
Responsive ■Resourceful ■Reliable EXPLORATION AND TESTING PROCEDURES 2 of 2
■Grain size analysis
■Moisture-density relationship (Proctor)
■California Bearing Ratio (CBR)
■Corrosion suite – water-soluble sulfate, pH, and electrical resistivity
The laboratory testing program included examination of soil samples by an engineer. Based on
the material’s texture and plasticity, we described and classified the soil samples in accordance
with the Unified Soil Classification System.
Chemical Analysis:A soil sample obtained from Boring B-2 at an approximate depth of 0 to 1.5
feet was submitted to Energy Laboratories for chemical analysis, to include the determination of
the soils’ pH, soluble sulfate content, and resistivity. The results of these chemical analyses are
discussed in the Corrosivity section.
Geotechnical Engineering Report
Concept Alt 2A ■ Bozeman, Montana
March 26, 2021 ■ Terracon Project No. 26205063
Responsive ■Resourceful ■Reliable PHOTOGRAPHY LOG 1 of 1
PHOTOGRAPHY LOG
Looking west across the site from boring B-3 Looking southeast at boring B-5
Looking north-northwest at boring B-6 Looking north at boring B-7
Responsive ■Resourceful ■Reliable
SITE LOCATION AND EXPLORATION PLANS
Contents:
Site Location Plan
Exploration Plan
Note: All attachments are one page unless noted above.
SITE LOCATION
Concept Alt 2A ■ Bozeman, Montana
March 26, 2021 ■ Terracon Project No. 26205063
Note to Preparer: This is a large table with outside borders. Just click inside the table
above this text box, then paste your GIS Toolbox image.
When paragraph markers are turned on you may notice a line of hidden text above and
outside the table – please leave that alone. Limit editing to inside the table.
The line at the bottom about the general location is a separate table line. You can edit
it as desired, but try to keep to a single line of text to avoid reformatting the page.
SITE LOCA TION
DIAGRAM IS FOR GENERAL LOCATION ONLY, AND IS NOT INTENDED FOR CONSTRUCTION PURPOSES MAP PROVIDED BY MICROSOFT BING MAPS
EXPLORATION PLAN
Concept Alt 2A ■ Bozeman, Montana
March 26, 2021 ■ Terracon Project No. 26205063
Note to Preparer: This is a large table with outside borders. Just click inside the table
above this text box, then paste your GIS Toolbox image.
When paragraph markers are turned on you may notice a line of hidden text above and
outside the table – please leave that alone. Limit editing to inside the table.
The line at the bottom about the general location is a separate table line. You can edit
it as desired, but try to keep to a single line of text to avoid reformatting the page.
EXPLORATION P LAN
DIAGRAM IS FOR GENERAL LOCATION ONLY, AND IS NOT INTENDED FOR CONSTRUCTION PURPOSES MAP PROVIDED BY MICROSOFT BING MAPS
EXPLORATION RESULTS
Contents:
Boring Logs (B-1 through B-8)
Atterberg Limits
Grain Size Distribution
Moisture Density Relationship
CBR
Corrosivity (7 pages)
Note: All attachments are one page unless noted above.
9-8-11N=19
9-19-42N=61
22-37-46
N=83
48-50/3"
50/4"
15.5
5.3
3.5
TOPSOIL, dark brown
LEAN CLAY WITH SAND (CL), dark brown, moist, very stiff
POORLY GRADED GRAVEL WITH SILT AND SAND (GP-GM), fine tocoarse grained, rounded to angular, dark brown to light brown, moist to wet,
very dense
Boring Terminated at 10.5 Feet
0.5
2.0
10.5
Hammer Type: AutomaticStratification lines are approximate. In-situ, the transition may be gradual.THIS BORING LOG IS NOT VALID IF SEPARATED FROM ORIGINAL REPORT. GEO SMART LOG-NO WELL 26205063 CONCEPT ALT 2A - .GPJ TERRACON_DATATEMPLATE.GDT 3/22/21WATER LEVELOBSERVATIONSDEPTH (Ft.)5
10 FIELD TESTRESULTSPERCENT FINESWATERCONTENT (%)DRY UNITWEIGHT (pcf)ATTERBERGLIMITS
LL-PL-PI
LOCATION See Exploration Plan
Latitude: 45.6706° Longitude: -111.0699°GRAPHIC LOGMODEL LAYERDEPTH
Page 1 of 1
Advancement Method:HSA
Abandonment Method:Boring backfilled with auger cuttings upon completion.
Notes:
Project No.: 26205063
Drill Rig: CME 75
BORING LOG NO. B-1
Q FACTORCLIENT:Denver, CO
Driller: O'Keefe
Boring Completed: 03-02-2021
PROJECT: Concept Alt 2A - Bozeman
See Exploration and Testing Procedures for adescription of field and laboratory procedures usedand additional data (If any).
See Supporting Information for explanation of
symbols and abbreviations.
West College Street & Professional Drive Bozeman, MT
SITE:
Boring Started: 03-02-2021
2110 Overland Ave Ste 124Billings, MT
While drilling
WATER LEVEL OBSERVATIONS
1
2 SAMPLE TYPE
9-6-3N=9
20-38-48N=86
22-50/5"
14-50/3"
22-45-50
N=95
50/2"
50/3"
34.9
3.1
16.1
6.4
TOPSOIL, dark brown
LEAN CLAY WITH SAND (CL), dark brown to light brown, moist, stiff
POORLY GRADED GRAVEL WITH SILT AND SAND (GP-GM), fine tocoarse grained, rounded to angular, brown to gray, moist to wet, very dense
Boring Terminated at 20.5 Feet
0.5
2.0
20.5
Hammer Type: AutomaticStratification lines are approximate. In-situ, the transition may be gradual.THIS BORING LOG IS NOT VALID IF SEPARATED FROM ORIGINAL REPORT. GEO SMART LOG-NO WELL 26205063 CONCEPT ALT 2A - .GPJ TERRACON_DATATEMPLATE.GDT 3/22/21WATER LEVELOBSERVATIONSDEPTH (Ft.)5
10
15
20 FIELD TESTRESULTSPERCENT FINESWATERCONTENT (%)DRY UNITWEIGHT (pcf)ATTERBERGLIMITS
LL-PL-PI
LOCATION See Exploration Plan
Latitude: 45.6706° Longitude: -111.0694°GRAPHIC LOGMODEL LAYERDEPTH
Page 1 of 1
Advancement Method:HSA
Abandonment Method:Boring backfilled with auger cuttings upon completion.
Notes:
Project No.: 26205063
Drill Rig: CME 75
BORING LOG NO. B-2
Q FACTORCLIENT:Denver, CO
Driller: O'Keefe
Boring Completed: 03-01-2021
PROJECT: Concept Alt 2A - Bozeman
See Exploration and Testing Procedures for adescription of field and laboratory procedures usedand additional data (If any).
See Supporting Information for explanation of
symbols and abbreviations.
West College Street & Professional Drive Bozeman, MT
SITE:
Boring Started: 03-01-2021
2110 Overland Ave Ste 124Billings, MT
While drilling
WATER LEVEL OBSERVATIONS
1
2 SAMPLE TYPE
6-6-3N=9
4-7-8N=15
16-29-36
N=65
17-40-33N=73
8-22-23
N=45
29.6
8.0
3.4
5.0
TOPSOIL, dark brown, moist
LEAN CLAY WITH SAND (CL), dark brown to light brown, moist, stiff
POORLY GRADED GRAVEL WITH SILT AND SAND (GP-GM), fine tocoarse grained, subrounded to subangular, dark brown to dark gray, moist towet, dense to very dense
Boring Terminated at 10.5 Feet
1.0
4.5
10.5
Hammer Type: AutomaticStratification lines are approximate. In-situ, the transition may be gradual.THIS BORING LOG IS NOT VALID IF SEPARATED FROM ORIGINAL REPORT. GEO SMART LOG-NO WELL 26205063 CONCEPT ALT 2A - .GPJ TERRACON_DATATEMPLATE.GDT 3/22/21WATER LEVELOBSERVATIONSDEPTH (Ft.)5
10 FIELD TESTRESULTSPERCENT FINESWATERCONTENT (%)DRY UNITWEIGHT (pcf)ATTERBERGLIMITS
LL-PL-PI
LOCATION See Exploration Plan
Latitude: 45.6701° Longitude: -111.0699°GRAPHIC LOGMODEL LAYERDEPTH
Page 1 of 1
Advancement Method:HSA
Abandonment Method:Boring backfilled with auger cuttings upon completion.
Notes:
Project No.: 26205063
Drill Rig: CME 75
BORING LOG NO. B-3
Q FACTORCLIENT:Denver, CO
Driller: O'Keefe
Boring Completed: 03-01-2021
PROJECT: Concept Alt 2A - Bozeman
See Exploration and Testing Procedures for adescription of field and laboratory procedures usedand additional data (If any).
See Supporting Information for explanation of
symbols and abbreviations.
West College Street & Professional Drive Bozeman, MT
SITE:
Boring Started: 03-01-2021
2110 Overland Ave Ste 124Billings, MT
While drilling
WATER LEVEL OBSERVATIONS
1
2 SAMPLE TYPE
27-30/3"
11-26-30N=56
15-35-34
N=69
20-32-32N=64
17-24-32
N=56
9
16.0
8.2
4.4
4.4 NP
FILL - AGGREGATE BASE COURSE , dark brown, moist, very dense
LEAN CLAY WITH SAND (CL), trace gravel, dark brown, moist
POORLY GRADED GRAVEL WITH SILT AND SAND (GP-GM), fine to
coarse grained, rounded to angular, dark brown, moist to wet, very dense
Boring Terminated at 10.5 Feet
1.0
2.5
10.5
Hammer Type: AutomaticStratification lines are approximate. In-situ, the transition may be gradual.THIS BORING LOG IS NOT VALID IF SEPARATED FROM ORIGINAL REPORT. GEO SMART LOG-NO WELL 26205063 CONCEPT ALT 2A - .GPJ TERRACON_DATATEMPLATE.GDT 3/22/21WATER LEVELOBSERVATIONSDEPTH (Ft.)5
10 FIELD TESTRESULTSPERCENT FINESWATERCONTENT (%)DRY UNITWEIGHT (pcf)ATTERBERGLIMITS
LL-PL-PI
LOCATION See Exploration Plan
Latitude: 45.67° Longitude: -111.0694°GRAPHIC LOGMODEL LAYERDEPTH
Page 1 of 1
Advancement Method:HSA
Abandonment Method:Boring backfilled with auger cuttings upon completion.
Notes:
Project No.: 26205063
Drill Rig: CME 75
BORING LOG NO. B-4
Q FACTORCLIENT:Denver, CO
Driller: O'Keefe
Boring Completed: 03-01-2021
PROJECT: Concept Alt 2A - Bozeman
See Exploration and Testing Procedures for adescription of field and laboratory procedures usedand additional data (If any).
See Supporting Information for explanation of
symbols and abbreviations.
West College Street & Professional Drive Bozeman, MT
SITE:
Boring Started: 03-01-2021
2110 Overland Ave Ste 124Billings, MT
While drilling
WATER LEVEL OBSERVATIONS
1
2 SAMPLE TYPE
8-6-6N=12
5-8-16N=24
17-50-39
N=89
50/3"
50-50/2"
71
25.6
7.1
4.1
19.9
35-22-13
TOPSOIL, dark brown, moist
LEAN CLAY WITH SAND (CL), light brown, moist, very stiff
POORLY GRADED GRAVEL WITH SILT AND SAND (GP-GM), fine to
coarse grained, rounded to angular, dark brown, moist to wet, very dense
Boring Terminated at 10.5 Feet
1.0
4.0
10.5
Hammer Type: AutomaticStratification lines are approximate. In-situ, the transition may be gradual.THIS BORING LOG IS NOT VALID IF SEPARATED FROM ORIGINAL REPORT. GEO SMART LOG-NO WELL 26205063 CONCEPT ALT 2A - .GPJ TERRACON_DATATEMPLATE.GDT 3/22/21WATER LEVELOBSERVATIONSDEPTH (Ft.)5
10 FIELD TESTRESULTSPERCENT FINESWATERCONTENT (%)DRY UNITWEIGHT (pcf)ATTERBERGLIMITS
LL-PL-PI
LOCATION See Exploration Plan
Latitude: 45.6698° Longitude: -111.0703°GRAPHIC LOGMODEL LAYERDEPTH
Page 1 of 1
Advancement Method:HSA
Abandonment Method:Boring backfilled with auger cuttings upon completion.
Notes:
Project No.: 26205063
Drill Rig: CME 75
BORING LOG NO. B-5
Q FACTORCLIENT:Denver, CO
Driller: O'Keefe
Boring Completed: 03-01-2021
PROJECT: Concept Alt 2A - Bozeman
See Exploration and Testing Procedures for adescription of field and laboratory procedures usedand additional data (If any).
See Supporting Information for explanation of
symbols and abbreviations.
West College Street & Professional Drive Bozeman, MT
SITE:
Boring Started: 03-01-2021
2110 Overland Ave Ste 124Billings, MT
While drilling
WATER LEVEL OBSERVATIONS
1
2 SAMPLE TYPE
6-4-5N=9
8-23-23N=46
15-16-18
N=34
14-27-33N=60
15-34-36
N=70
23-50/5"
16-50/5"
27.2
17.2
4.6
7.1
TOPSOIL, dark brown, moist
LEAN CLAY WITH SAND (CL), light brown, moist
POORLY GRADED GRAVEL WITH SILT AND SAND (GP-GM), fine tocoarse grained, rounded to angular, brown to gray, moist to wet, dense tovery dense
Boring Terminated at 20.5 Feet
1.0
3.0
20.5
Hammer Type: AutomaticStratification lines are approximate. In-situ, the transition may be gradual.THIS BORING LOG IS NOT VALID IF SEPARATED FROM ORIGINAL REPORT. GEO SMART LOG-NO WELL 26205063 CONCEPT ALT 2A - .GPJ TERRACON_DATATEMPLATE.GDT 3/22/21WATER LEVELOBSERVATIONSDEPTH (Ft.)5
10
15
20 FIELD TESTRESULTSPERCENT FINESWATERCONTENT (%)DRY UNITWEIGHT (pcf)ATTERBERGLIMITS
LL-PL-PI
LOCATION See Exploration Plan
Latitude: 45.6696° Longitude: -111.0699°GRAPHIC LOGMODEL LAYERDEPTH
Page 1 of 1
Advancement Method:HSA
Abandonment Method:Boring backfilled with auger cuttings upon completion.
Notes:
Project No.: 26205063
Drill Rig: CME 75
BORING LOG NO. B-6
Q FACTORCLIENT:Denver, CO
Driller: O'Keefe
Boring Completed: 03-01-2021
PROJECT: Concept Alt 2A - Bozeman
See Exploration and Testing Procedures for adescription of field and laboratory procedures usedand additional data (If any).
See Supporting Information for explanation of
symbols and abbreviations.
West College Street & Professional Drive Bozeman, MT
SITE:
Boring Started: 03-01-2021
2110 Overland Ave Ste 124Billings, MT
While drilling
WATER LEVEL OBSERVATIONS
1
2 SAMPLE TYPE
7-4-3N=7
6-25-49N=74
24-38-50/5"
78
21.9
26.3
51.3
4.1
43-25-18
TOPSOIL, dark brown, moist
LEAN CLAY WITH SAND, dark brown to light brown, moist, medium stiff
POORLY GRADED GRAVEL WITH SILT AND SAND (GP-GM), fine to
coarse grained, rounded to angular, dark brown, moist, very dense
Boring Terminated at 5.5 Feet
0.5
2.5
5.5
Hammer Type: AutomaticStratification lines are approximate. In-situ, the transition may be gradual.THIS BORING LOG IS NOT VALID IF SEPARATED FROM ORIGINAL REPORT. GEO SMART LOG-NO WELL 26205063 CONCEPT ALT 2A - .GPJ TERRACON_DATATEMPLATE.GDT 3/22/21WATER LEVELOBSERVATIONSDEPTH (Ft.)5 FIELD TESTRESULTSPERCENT FINESWATERCONTENT (%)DRY UNITWEIGHT (pcf)ATTERBERGLIMITS
LL-PL-PI
LOCATION See Exploration Plan
Latitude: 45.6704° Longitude: -111.0706°GRAPHIC LOGMODEL LAYERDEPTH
Page 1 of 1
Advancement Method:HSA
Abandonment Method:Boring backfilled with auger cuttings upon completion.
Notes:
Project No.: 26205063
Drill Rig: CME 75
BORING LOG NO. B-7
Q FACTORCLIENT:Denver, CO
Driller: O'Keefe
Boring Completed: 03-02-2021
PROJECT: Concept Alt 2A - Bozeman
See Exploration and Testing Procedures for adescription of field and laboratory procedures usedand additional data (If any).
See Supporting Information for explanation of
symbols and abbreviations.
West College Street & Professional Drive Bozeman, MT
SITE:
Boring Started: 03-02-2021
2110 Overland Ave Ste 124Billings, MT
WATER LEVEL OBSERVATIONS
Groundwater not encountered
1
2 SAMPLE TYPE
4-8-8N=16
14-29-50N=79
28-45-48
N=93
16.7
4.9
3.1
TOPSOIL, moist
LEAN CLAY WITH SAND (CL), dark brown, moist, very stiff
POORLY GRADED GRAVEL WITH SILT AND SAND (GP-GM), fine tocoarse grained, rounded to angular, dark brown to gray, moist, very dense
Boring Terminated at 5.5 Feet
0.5
2.0
5.5
Hammer Type: AutomaticStratification lines are approximate. In-situ, the transition may be gradual.THIS BORING LOG IS NOT VALID IF SEPARATED FROM ORIGINAL REPORT. GEO SMART LOG-NO WELL 26205063 CONCEPT ALT 2A - .GPJ TERRACON_DATATEMPLATE.GDT 3/22/21WATER LEVELOBSERVATIONSDEPTH (Ft.)5 FIELD TESTRESULTSPERCENT FINESWATERCONTENT (%)DRY UNITWEIGHT (pcf)ATTERBERGLIMITS
LL-PL-PI
LOCATION See Exploration Plan
Latitude: 45.6708° Longitude: -111.0697°GRAPHIC LOGMODEL LAYERDEPTH
Page 1 of 1
Advancement Method:HSA
Abandonment Method:Boring backfilled with auger cuttings upon completion.
Notes:
Project No.: 26205063
Drill Rig: CME 75
BORING LOG NO. B-8
Q FACTORCLIENT:Denver, CO
Driller: O'Keefe
Boring Completed: 03-02-2021
PROJECT: Concept Alt 2A - Bozeman
See Exploration and Testing Procedures for adescription of field and laboratory procedures usedand additional data (If any).
See Supporting Information for explanation of
symbols and abbreviations.
West College Street & Professional Drive Bozeman, MT
SITE:
Boring Started: 03-02-2021
2110 Overland Ave Ste 124Billings, MT
WATER LEVEL OBSERVATIONS
Groundwater not encountered
1
2 SAMPLE TYPE
CH or OHCL or OLML or OL
MH or OH
ATTERBERG LIMITS RESULTS
ASTM D4318
˘
ˇ
ˆ
˙˘˝
˛˚˜ˇ˝ ˇ˛!
ˇ!"#$%&&'$($)(%*##%+&
˘(,
%-.+/˝
˛˚˜ˇ!%01$&$2 %-.+
ˇ!˙3˚˛
˘,(/˚
˚,(&+4,$
&&'#/˝ ˚˛˚˛ˇ˛ˇ˚5˘3ˇ˛ˇ˘3˛˚˝˚˛6˛ˇ˚˛7ˇ˛ ˇ˛6˝˚ˇ276˜ˇ˛˛˚8˘ˇ˝ˇ76˘99
Boring ID Depth LL PL PI
2
2
2:
;7
:7
:7
Fines
72
27
2
6"26˝"ˇ26˛˘ˇ˘6˛5ˇ<$=+4˘
ˇ<$=˘
ˇ<$=˘
DescriptionUSCS
CL-ML
+4 2
0
5
10
15
20
25
30
35
40
45
50
55
60
65
70
75
80
85
90
95
100
0.0010.010.1110100
30 40 501.5 200681014413/4 1/2 60
GRAIN SIZE IN MILLIMETERSPERCENT FINER BY WEIGHTHYDROMETERU.S. SIEVE OPENING IN INCHES U.S. SIEVE NUMBERS
4 3/8 3 10014032
GRAIN SIZE DISTRIBUTION
ASTM D422 / ASTM C136
6 16 20
PROJECT NUMBER: 26205063
SITE: West College Street & Professional
Drive
Bozeman, MT
PROJECT: Concept Alt 2A - Bozeman
CLIENT: Q FACTOR Denver, CO
2110 Overland Ave Ste 124Billings, MT
LABORATORY TESTS ARE NOT VALID IF SEPARATED FROM ORIGINAL REPORT. GRAIN SIZE: USCS-2 26205063 CONCEPT ALT 2A - .GPJ TERRACON_DATATEMPLATE.GDT 3/16/21mediumcoarse coarsefine fineCOBBLESGRAVEL SAND SILT OR CLAY
B-4
B-5
B-7 and B-8
WELL-GRADED GRAVEL with SILT and SAND (GW-GM)
LEAN CLAY with SAND (CL)
LEAN CLAY with SAND (CL)
NP
35
43
2.30NP
13
18
NP
22
25
83.586.5 - 8
2 - 3.5
1 - 2
4.4
7.1
26.3
B-4
B-5
B-7
9.3
71.5
78.1
6.5 - 8
2 - 3.5
1 - 2
49.6
4.9
4.9
41.0
23.6
17.0
37.5
19
12.5
7.31 1.212 0.087
Boring ID Depth WC (%)LL PL PI Cc Cu
%Clay%Fines%Silt%Sand%Gravel Boring ID Depth D100 D60 D30 D10
USCS Classification
%Cobbles
0.0
0.0
0.0
B-4
B-5
B-7 and B-8
and B-8
75
80
85
90
95
100
105
110
115
120
125
130
135
0 5 10 15 20 25 30 35 40 45DRY DENSITY, pcfWATER CONTENT, %
Z
A
V
f
o
r
G
s =
2
.
8
Z
A
V
f
o
r
G
s =
2
.
7
ZA
V
f
o
r
G
s =
2
.
6
MOISTURE-DENSITY RELATIONSHIP
ASTM D698/D1557
PROJECT NUMBER: 26205063
SITE: West College Street & ProfessionalDrive Bozeman, MT
PROJECT: Concept Alt 2A - Bozeman
CLIENT: Q FACTOR
Denver, CO
2110 Overland Ave Ste 124Billings, MT
LABORATORY TESTS ARE NOT VALID IF SEPARATED FROM ORIGINAL REPORT. COMPACTION - V2 26205063 CONCEPT ALT 2A - .GPJ TERRACON_DATATEMPLATE.GDT 3/16/21ASTM D698 Method B
Source of Material B-7 and B-8 @ 1 - 2 feet
Description of Material
Remarks:
Test Method
PCF
%
TEST RESULTS
LEAN CLAY with SAND(CL)
Maximum Dry Density
%
43
LL
100.0
78.1
Optimum Water Content
PIPL
25 18
ATTERBERG LIMITS
21.6
Percent Fines
75
80
85
90
95
100
105
110
115
120
125
130
135
0 5 10 15 20 25 30 35 40 45
PROJECT:Concept Alt 2A PROJECT NO:26205063
LOCATION:Bozeman, Montana
MATERIAL:Lean Clay with Sand
SAMPLE SOURCE:B-7 & B-8 Composite: 1 - 2 feet DATE:3/22/2021
REVIEWED BY:TG
COMPACTION(%)94.2%CORRECTED
COMPACTION:Recompacted at approx 95% MDD near optimum moisture PENETRATION C B R
PERCENT SWELL 0.9%0.100 5.2%
0.200 4.5%
BEFORE SOAK AFTER SOAK
DRY DENSITY 94.2 lbs./cu.ft 93.3 lbs./cu.ft D698 PROCTOR
PERCENT MOISTURE 21.6 %30.9 %DRY DENSITY(pcf) 100.0
MOISTURE(%)21.6
SURCHARGE WEIGHT 10 lbs.
CBR (CALIFORNIA BEARING RATIO) OF LABORATORY-COMPACTED SOILS (ASTM D1883)
0.0
20.0
40.0
60.0
80.0
100.0
120.0
140.0
160.0
0 0.1 0.2 0.3 0.4 0.5PENETRATIONSTRESS(psi)PENETRATION (in)
2110 Overland Avenue, Suite 124, Billings, Montana PHONE: (406) 656-3072 FAX: (406) 656-3578 ISSUED: 3/22/2021
ANALYTICAL SUMMARY REPORT
The analyses presented in this report were performed by Energy Laboratories, Inc., 1120 S 27th St., Billings, MT 59101, unless
otherwise noted. Any exceptions or problems with the analyses are noted in the Laboratory Analytical Report, the QA/QC Summary
Report, or the Case Narrative. Any issues encountered during sample receipt are documented in the Work Order Receipt Checklist.
The results as reported relate only to the item(s) submitted for testing. This report shall be used or copied only in its entirety. Energy
Laboratories, Inc. is not responsible for the consequences arising from the use of a partial report.
If you have any questions regarding these test results, please contact your Project Manager.
Lab ID Client Sample ID Collect Date Receive Date Matrix Test
Report Approved By:
B21030507-001 B-2 [0-1.5]feet 03/01/21 0:00 03/05/21 Soil pH, Saturated Paste
Saturated Paste Extraction ASA
Resistivity, Sat Paste
Sulfate-Geochemical
Terracon Consultants
Project Name:26205063 Q-Factor
Work Order:B21030507
2110 Overland Ave Ste 124
Billings , MT 59102-6440
March 17, 2021
B5647Quote ID:
Energy Laboratories Inc Billings MT received the following 1 sample for Terracon Consultants on 3/5/2021 for analysis.
Page 1 of 7
LABORATORY ANALYTICAL REPORT
Client:Terracon Consultants
Project:26205063 Q-Factor
Lab ID:B21030507-001
Client Sample ID:B-2 [0-1.5]
Collection Date:03/01/21
Matrix:Soil
Report Date:03/17/21
DateReceived:03/05/21
Prepared by Billings, MT Branch
Analyses Result Units Analysis Date / ByRLMethod
MCL/
QCLQualifiers
SATURATED PASTE EXTRACT
03/10/21 12:31 / srm1ohm-cm1870Resistivity, Sat. Paste Calculation
03/10/21 12:31 / srm0.1s.u.6.7pH, sat. paste ASA10-3
CHEMICAL CHARACTERISTICS
03/16/21 15:00 / srm0.01wt%NDSulfate, HCL Extractable MTDOT
Report
Definitions:
RL - Analyte Reporting Limit MCL - Maximum Contaminant Level
QCL - Quality Control Limit ND - Not detected at the Reporting Limit (RL)
Page 2 of 7
Client:Terracon Consultants Work Order:B21030507
QA/QC Summary Report
03/17/21Report Date:
Analyte Result %REC RPDLow Limit High Limit RPDLimitRLUnits QualCount
Prepared by Billings, MT Branch
Method:ASA10-3 Batch: 153467
Lab ID:B21030378-001A DUP 03/10/21 12:31Sample Duplicate Run: MISC-SOIL_210310A
pH, sat. paste 100.10 1.47.30 s.u.
Lab ID:LCS-2103101231 03/10/21 12:31Laboratory Control Sample Run: MISC-SOIL_210310A
pH, sat. paste 96 90 1100.107.20 s.u.
Qualifiers:
RL - Analyte Reporting Limit ND - Not detected at the Reporting Limit (RL)
Page 3 of 7
Client:Terracon Consultants Work Order:B21030507
QA/QC Summary Report
03/17/21Report Date:
Analyte Result %REC RPDLow Limit High Limit RPDLimitRLUnits QualCount
Prepared by Billings, MT Branch
Method:Calculation Batch: 153467
Lab ID:B21030378-001A DUP 03/10/21 12:31Sample Duplicate Run: MISC-SOIL_210310A
Resistivity, Sat. Paste 70 130 301.0 0.02603ohm-cm
Lab ID:LCS-2103101231 03/10/21 12:31Laboratory Control Sample Run: MISC-SOIL_210310A
Resistivity, Sat. Paste 102 70 1301.0249ohm-cm
Qualifiers:
RL - Analyte Reporting Limit ND - Not detected at the Reporting Limit (RL)
Page 4 of 7
Client:Terracon Consultants Work Order:B21030507
QA/QC Summary Report
03/17/21Report Date:
Analyte Result %REC RPDLow Limit High Limit RPDLimitRLUnits QualCount
Prepared by Billings, MT Branch
Method:MTDOT Batch: R357754
Lab ID:MBLK1 03/16/21 14:59Method Blank Run: MISC-SOIL_210317A
Sulfate, HCL Extractable 0.0008 wt%
Lab ID:B21030507-001A DUP 03/16/21 15:00Sample Duplicate Run: MISC-SOIL_210317A
Sulfate, HCL Extractable 300.01NDwt%
Lab ID:LCS 03/16/21 15:00Laboratory Control Sample Run: MISC-SOIL_210317A
Sulfate, HCL Extractable 94 70 1300.010.05 wt%
Qualifiers:
RL - Analyte Reporting Limit ND - Not detected at the Reporting Limit (RL)
Page 5 of 7
Shipping container/cooler in good condition?
Custody seals intact on all shipping container(s)/cooler(s)?
Custody seals intact on all sample bottles?
Chain of custody present?
Chain of custody signed when relinquished and received?
Chain of custody agrees with sample labels?
Samples in proper container/bottle?
Sample containers intact?
Sufficient sample volume for indicated test?
All samples received within holding time?
(Exclude analyses that are considered field parameters
such as pH, DO, Res Cl, Sulfite, Ferrous Iron, etc.)
Container/Temp Blank temperature:
Water - VOA vials have zero headspace?
Water - pH acceptable upon receipt?
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
No
No
No
No
No
No
No
No
No
No
No
No
££
£
£
R
R
R
R
R
R
R
£
£
£
£
£
£
£
£
£
£
£
£
£
Not Present
Not Present
Not Present
R
R
R
No VOA vials submitted
Not Applicable R
R
17.8°C No Ice
3/5/2021Taylor K. Burris
Hand Del
tkb
Date Received:
Received by:
Login completed by:
Carrier name:
BL2000\cindy
3/10/2021
Reviewed by:
Reviewed Date:
Contact and Corrective Action Comments:
None
Temp Blank received in all shipping container(s)/cooler(s)?Yes No£R Not Applicable £
Lab measurement of analytes considered field parameters that require analysis within 15 minutes of sampling such as
pH, Dissolved Oxygen and Residual Chlorine, are qualified as being analyzed outside of recommended holding time.
Solid/soil samples are reported on a wet weight basis (as received) unless specifically indicated. If moisture corrected,
data units are typically noted as –dry. For agricultural and mining soil parameters/characteristics, all samples are dried
and ground prior to sample analysis.
Radiochemical precision results represent a 2-sigma Total Measurement Uncertainty.
Standard Reporting Procedures:
Work Order Receipt Checklist
Terracon Consultants B21030507
Page 6 of 7
Page 7 of 7
SUPPORTING INFORMATION
Contents:
General Notes
Unified Soil Classification System
Note: All attachments are one page unless noted above.
Concept Alt 2A - Bozeman Bozeman, MT
Terracon Project No. 26205063
500 to 1,000
> 8,000
4,000 to 8,000
2,000 to 4,000
1,000 to 2,000
less than 500
Unconfined Compressive StrengthQu, (psf)
GrabSample Split Spoon
N
(HP)
(T)
(DCP)
UC
(PID)
(OVA)
Standard Penetration TestResistance (Blows/Ft.)
Hand Penetrometer
Torvane
Dynamic Cone Penetrometer
Unconfined CompressiveStrength
Photo-Ionization Detector
Organic Vapor Analyzer
SAMPLING WATER LEVEL FIELD TESTS
GENERAL NOTES
DESCRIPTION OF SYMBOLS AND ABBREVIATIONS
Water levels indicated on the soil boring logs are
the levels measured in the borehole at the timesindicated. Groundwater level variations will occur
over time. In low permeability soils, accuratedetermination of groundwater levels is not
possible with short term water levelobservations.
Water Initially
Encountered
Water Level After a
Specified Period of Time
Water Level Aftera Specified Period of Time
Cave InEncountered
Exploration point locations as shown on the Exploration Plan and as noted on the soil boring logs in the form of Latitude
and Longitude are approximate. See Exploration and Testing Procedures in the report for the methods used to locate theexploration points for this project. Surface elevation data annotated with +/- indicates that no actual topographical surveywas conducted to confirm the surface elevation. Instead, the surface elevation was approximately determined from
topographic maps of the area.
LOCATION AND ELEVATION NOTES
Soil classification as noted on the soil boring logs is based Unified Soil Classification System. Where sufficient laboratory
data exist to classify the soils consistent with ASTM D2487 "Classification of Soils for Engineering Purposes" thisprocedure is used. ASTM D2488 "Description and Identification of Soils (Visual-Manual Procedure)" is also used toclassify the soils, particularly where insufficient laboratory data exist to classify the soils in accordance with ASTM D2487.
In addition to USCS classification, coarse grained soils are classified on the basis of their in-place relative density, and
fine-grained soils are classified on the basis of their consistency. See "Strength Terms" table below for details. The ASTMstandards noted above are for reference to methodology in general. In some cases, variations to methods are applied as a
result of local practice or professional judgment.
DESCRIPTIVE SOIL CLASSIFICATION
The soil boring logs contained within this document are intended for application to the project as described in thisdocument. Use of these soil boring logs for any other purpose may not be appropriate.
RELEVANCE OF SOIL BORING LOG
STRENGTH TERMS
Standard Penetration orN-ValueBlows/Ft.
Descriptive Term(Density)
Hard
15 - 30Very Stiff> 50Very Dense
8 - 15Stiff30 - 50Dense
4 - 8Medium Stiff10 - 29Medium Dense
2 - 4Soft4 - 9Loose
0 - 1Very Soft0 - 3Very Loose
(50% or more passing the No. 200 sieve.)Consistency determined by laboratory shear strength testing, field visual-manualprocedures or standard penetration resistance
> 30
Descriptive Term(Consistency)Standard Penetration orN-ValueBlows/Ft.
(More than 50% retained on No. 200 sieve.)
Density determined by Standard Penetration Resistance
CONSISTENCY OF FINE-GRAINED SOILSRELATIVE DENSITY OF COARSE-GRAINED SOILS
UNIFIED SOIL CLASSIFICATION SYSTEM
UNIFIED SOI L CLASSI FICATI ON SYSTEM
Criteria for Assigning Group Symbols and Group Names Using Laboratory Tests A
Soil Classification
Group
Symbol Group Name B
Coarse-Grained Soils:
More than 50% retained
on No. 200 sieve
Gravels:
More than 50% ofcoarse fraction
retained on No. 4 sieve
Clean Gravels:
Less than 5% finesC
Cu ³ 4 and 1 £ Cc £ 3 E GW Well-graded gravel F
Cu < 4 and/or [Cc<1 or Cc>3.0]E GP Poorly graded gravelF
Gravels with Fines:
More than 12% finesC
Fines classify as ML or MH GM Silty gravelF, G, H
Fines classify as CL or CH GC Clayey gravelF, G, H
Sands:
50% or more of coarsefraction passes No. 4
sieve
Clean Sands:
Less than 5% finesD
Cu ³ 6 and 1 £ Cc £ 3E SW Well-graded sandI
Cu < 6 and/or [Cc<1 or Cc>3.0]E SP Poorly graded sandI
Sands with Fines:
More than 12% fines D
Fines classify as ML or MH SM Silty sandG, H, I
Fines classify as CL or CH SC Clayey sand G, H, I
Fine-Grained Soils:
50% or more passes the
No. 200 sieve
Silts and Clays:
Liquid limit less than 50
Inorganic:PI > 7 and plots on or above “A”
lineJ CL Lean clayK, L, M
PI < 4 or plots below “A” line J ML Silt K, L, M
Organic:Liquid limit - oven dried < 0.75 OL Organic clayK, L, M, N
Liquid limit - not dried Organic silt K, L, M, O
Silts and Clays:
Liquid limit 50 or more
Inorganic:PI plots on or above “A” line CH Fat clayK, L, M
PI plots below “A” line MH Elastic Silt K, L, M
Organic:Liquid limit - oven dried < 0.75 OH Organic clayK, L, M, P
Liquid limit - not dried Organic silt K, L, M, Q
Highly organic soils:Primarily organic matter, dark in color, and organic odor PT Peat
A Based on the material passing the 3-inch (75-mm) sieve.
B If field sample contained cobbles or boulders, or both, add “with cobbles
or boulders, or both” to group name.
C Gravels with 5 to 12% fines require dual symbols: GW-GM well-graded
gravel with silt, GW-GC well-graded gravel with clay, GP-GM poorly
graded gravel with silt, GP-GC poorly graded gravel with clay.
D Sands with 5 to 12% fines require dual symbols: SW-SM well-graded
sand with silt, SW-SC well-graded sand with clay, SP-SM poorly graded
sand with silt, SP-SC poorly graded sand with clay.
E Cu = D60/D10 Cc =
6010
2
30
DxD
)(D
F If soil contains ³ 15% sand, add “with sand” to group name.
G If fines classify as CL-ML, use dual symbol GC-GM, or SC-SM.
HIf fines are organic, add “with organic fines” to group name.
I If soil contains ³ 15% gravel, add “with gravel” to group name.
J If Atterberg limits plot in shaded area, soil is a CL-ML, silty clay.
KIf soil contains 15 to 29% plus No. 200, add “with sand” or “with
gravel,” whichever is predominant.
L If soil contains ³ 30% plus No. 200 predominantly sand, add
“sandy” to group name.
MIf soil contains ³ 30% plus No. 200, predominantly gravel, add
“gravelly” to group name.
NPI ³ 4 and plots on or above “A” line.
OPI < 4 or plots below “A” line.
P PI plots on or above “A” line.
QPI plots below “A” line.
Appendix E
DETAILS
SLOTTED DRYWELL MANHOLE DETAIL F