HomeMy WebLinkAbout012 - Stites Geotechnical Report_Blk 20 Bax Med 2A
February 25, 2025
Jonathan Stites
15 Meridian Road
Three Forks, Montana 59752
Email: stites0374@msn.com
RE: Geotechnical Investigation Report
Lots 4-6, Block 20
Baxter Meadows Subdivision Phase 2A
Bozeman, Montana
IMEG# 24006453.00
Dear Jonathan,
Per your request, IMEG has conducted a subsurface soils investigation for the above referenced property
located in Bozeman, Montana. The scope of services was to conduct a subsurface soils investigation and
provide a soils investigation report for a new commercial structure. The report documents the subsurface
conditions, soil properties, and provides foundation design and general earthwork recommendations.
Proposed Construction
A commercial office building is proposed for construction. The structure will utilize a slab-on-grade with
stem wall foundation. The structure is planned to have a total height of 14.5 feet and will be a single story.
In determining the allowable bearing capacity and settlement estimates, it has been assumed that the
foundation footings will not be subjected to unusual loading conditions such as eccentric loads. A footing
is eccentrically loaded if the load transferred to the footing is not directed through the center of the footing.
If any of the foundation footings will be eccentrically loaded, please contact this office so we can
appropriately revise our allowable bearing capacity and settlement estimates.
Subsurface Soil and Conditions
On October 24, 2024 a member of the staff of IMEG visited the site to conduct a subsurface soils
investigation. The subsurface soils investigation consisted of examining three exploratory test pit
excavations. The exploratory test pits were excavated with tracked excavator provided by Elevation
Excavating. The soil profile revealed by the exploratory excavation was logged and visually classified
according to ASTM D 2488, which utilizes the nomenclature of the Unified Soil Classification System
Jonathan Stites – Geotechnical Investigation
February 25, 2025 Page 2 of 12
(USCS). The relative density of each soil layer was estimated based on probing of the excavation sidewalls
with a rock hammer and penetration tests performed with a static cone penetrometer. Any evidence of
seepage or other groundwater conditions were also noted. The location of the exploratory test pits are
shown on the included Test Pit Location Map.
The following paragraphs briefly summarize the subsurface soils and conditions observed in the exploratory
test pits excavated for the field investigation. The soil horizons are described as they were encountered in
the test pit excavations, starting with the horizon nearest the surface and proceeding with each additional
horizon encountered with depth. Please refer to the attached test pit logs for more detailed information.
The first soil horizon encountered in each exploratory excavation was undocumented fill, which was
present to depths varying from approximately 0.83 feet below grounds surface (bgs) to 1.25 feet bgs. This
material was a mix of clay, gravel and sand. This material must be removed from beneath all foundation
elements and in any area that will receive asphalt or concrete pavements.
The second soil horizon encountered in each exploratory excavation was an Organic Soil of Low plasticity
(OL). This material was black in color, moist and soft. This material was encountered to depths varying
from 2.0 feet bgs to 2.41 feet bgs. Organic soils are highly compressible and are not suitable for foundation
support. This material must be removed from beneath all foundation elements and in any area that will
receive asphalt or concrete pavement.
Underlying the Organic Soil in each exploratory excavation was a Lean Clay (CL), which was present to
depths varying form 4.0 feet bgs to 4.5 feet bgs. This material was tan to grayish white in color and was
moist to very moist. Penetration tests performed on this material with a static cone penetrometer indicated
it was very soft in consistency. This material is moisture sensitive and not suitable for foundation support
and must be removed from beneath the structure’s foundation.
Underlying the Lean Clay in each exploratory excavation was a Poorly Graded Gravel with Sand and Cobbles
(GP), the typical bearing material for most structures within the City of Bozeman. This material was found
to be in a medium dense condition and is suitable for foundation support. Groundwater was encountered
within this material at depths varying from 6.50 feet bgs to 7.33 feet bgs.
Based on the subsurface investigation, it is recommended that the proposed structure bear on the Poorly
Graded Gravel with Sand and Cobbles or on properly placed and compacted structural fill overlying the
Poorly Graded Gravel with Sand and Cobbles.
Groundwater
Groundwater was encountered at depths varying from 6.5 feet bgs to 7.33 feet bgs in the exploratory
excavations. Evidence of seasonally high groundwater (such as a lack of calcium deposits, gleyed soils,
Jonathan Stites – Geotechnical Investigation
February 25, 2025 Page 3 of 12
increase in moisture content and lack of organic roots) was observed starting at a depth of approximately
3.0 feet bgs, suggesting groundwater may be rising up to near this elevation seasonally.
Seismicity
The general Bozeman area is located in an earthquake zone known as the intermountain seismic belt,
which is a zone of earthquake activity that extends from northwest Montana to southern Arizona. In
general, this zone is expected to experience moderately frequent, potentially damaging earthquakes. With
that in mind, it is important that the structure be designed to withstand horizontal seismic accelerations
that may be induced by such an earthquake, as is required by the International Building Code.
The USGS provides seismic design parameters for the design of buildings and bridges across the United
States. These parameters are based on the 2015 National Earthquake Hazards Reduction Program (NEHRP)
Recommended Seismic Provisions. The primary intent of the NEHRP Recommended Seismic Provisions
is to prevent, for typical buildings and structures, serious injury and life loss caused by damage from
earthquake ground shaking.
The following seismic design parameters were determined for the subject property using the USGS
Seismic Design Application:
Approximate site Location:
Latitude = 45.700° N
Longitude = 111.087° W
Maximum Considered Earthquake (MCE) Spectral Response Acceleration Parameters:
Short Period (SS) = 0.717g
1-Second Period (S1) = 0.222g
Site Coefficients and Adjusted MCE Spectral Response Acceleration Parameters:
SMS = 0.879g
SM1 = 0.479g
Design Spectral Response Acceleration Parameters:
SDS = 0.586g
SD1 = 0.319g
The seismic site class for this project is D.
Jonathan Stites – Geotechnical Investigation
February 25, 2025 Page 4 of 12
Foundation Recommendations
Based on the subsurface soils encountered in the exploratory excavations, it will be acceptable to utilize a
slab-on-grade with stem wall foundation as planned. Please find the following as general recommendations
for all foundation elements:
The foundation footings are to bear on the Poorly Graded Gravel with Sand and Cobbles or on
properly placed and compacted structural fill overlying this material.
If construction takes place during the colder months of the year, the subgrade must be protected
from freezing. This may require the use of insulating blankets and/or ground heaters
Allowable Bearing Capacity
The bearing capacity of a soil is defined as the ultimate pressure per unit area by the foundation that can
be supported by the soil in excess of the pressure caused by the surrounding soil at the footing level.
Bearing capacity is determined by the physical and chemical properties of the soil located beneath the
proposed structure’s footings and can also be influenced by the water table.
It is recommended that the loads from the proposed structure be transmitted to the Poorly Graded Gravel
with Sand and Cobbles or on properly placed and compacted structural fill overlying the Poorly Graded
Gravel with Sand and Cobbles. For this scenario it is recommended that an allowable bearing capacity of
2,500 pounds per square foot be used to dimension the foundation footings.
The allowable bearing capacity may be increased by one third for short term loading conditions such as
those from wind or seismic forces.
Settlement
While the soil at the site may be able to physically support the footings, it is also important to analyze the
possible settlement of the structure.
When a soil deposit is loaded by a structure, deformations within the soil deposit will occur. The total
vertical deformation of the soil at the surface is called total settlement. Total settlement is made up of two
components: elastic settlement and consolidation settlement. Elastic settlement is the result of soil
particles rearranging themselves into a denser configuration due to a load being imposed on them and
usually occurs during the construction process and shortly after. Consolidation settlement occurs more
slowly and over time as water within the pore spaces of a soil are forced out and the soil compresses as
the stress from the load is transferred from the water molecules to the soil particles. Consolidation
settlement is more of a concern with fine-grained soils with low permeability and high in-situ moisture
contents. The degree of settlement is a function of the type of bearing material, the bearing pressure of
Jonathan Stites – Geotechnical Investigation
February 25, 2025 Page 5 of 12
the foundation elements, local groundwater conditions, and in some cases determines the allowable
bearing capacity for a structures’ footings.
In addition to analyzing total settlement, the potential for differential settlement must also be considered.
Differential settlement occurs in soils that are not homogeneous over the length of the foundation or in
situations where the foundation rests on cut and fill surfaces. If the foundation rests on structural fill
overlaying properly compacted gravelly soils, differential settlement is expected to be well within tolerable
limits. Areas that have significantly more fill under the foundation footings (four feet of more) create greater
potential for differential settlement. In these cases the structural fill must be installed properly and tested
frequently. Compaction efforts and structural fill consistence are vital in minimizing differential settlement.
A settlement analysis based on conservative soil parameter estimates, the recommended allowable
bearing capacity, and the assumption that all recommendations made in this report are properly adhered
to, indicates the total and differential settlement are expected to be 1/2-inch or less. Structures of the type
assumed can generally tolerate this amount of movement, however, these values should be checked by a
licensed structural engineer to verify that they are acceptable.
Please note that the settlement estimates are based on loads originating from the proposed structure. If
additional loads are introduced, such as the placement of large quantities of fill, our office should be
contacted to re-evaluate the settlement estimates.
Lateral Pressures
Lateral pressures imposed upon foundation and retaining walls due to wind, seismic forces, and earth
pressures may be resisted by the development of passive earth pressures and/or frictional resistance
between the base of the footings and the supporting soils. If a foundation or retaining wall is restrained
from moving, the lateral earth pressure exerted on the wall is called the at-rest earth pressure. If a
foundation or retaining wall is allowed to tilt away from the retained soil, the lateral earth pressure exerted
on the wall is called the active earth pressure. Passive earth pressure is the resistance pressure the
foundation or retaining wall develops due to the wall being pushed laterally into the earth on the opposite
side of the retained soil. Each of these pressures is proportional to the distance below the earth surface,
the unit weight of the soil, and the shear strength properties of the soil.
It is recommended that all foundation and retaining walls be backfilled with well-draining granular material.
Well-draining granular backfill has a more predictable behavior in terms of the lateral earth pressure exerted
on the foundation or retaining wall and will not generate expansive related forces. If backfill containing
significant quantities of clayey material is used, the seepage of water into the backfill could potentially
generate horizontal swelling pressures well above at-rest values. Additionally, seepage into a clayey
backfill material will also cause significant hydrostatic pressures to build up against the foundation wall due
to the low permeability of clay soils and will make the backfill susceptible to frost action.
Jonathan Stites – Geotechnical Investigation
February 25, 2025 Page 6 of 12
Subsurface walls that are restrained from moving at the top are recommended to be designed for an
equivalent fluid pressure of 70 pounds per cubic foot (pcf) (at-rest pressure); the equivalent fluid pressure
is the product of the retained soils unit weight and its coefficient of active or at-rest earth pressure. Any
subsurface walls that are allowed to move away from the restrained soil, such as cantilevered retaining
walls, are recommended to be designed for an equivalent fluid pressure of 55 pcf (active pressure). For
passive pressures, an equivalent fluid pressure of 275 pcf is recommended, and the coefficient of friction
between the cast-in-place concrete and the Poorly Graded Gravel with Sand and Cobbles is 0.5.
These recommended values were calculated assuming a near horizontal backfill and that a mix of the Lean
Clay, Undocumented Fill and Poorly Graded Gravel with Sand and Cobbles will be used as foundation wall
backfill. It is also assumed that the backfill will be compacted as recommended in this report. Also, please
note that these design pressures do not include a factor of safety and are for static conditions, they do not
account for additional forces that may be induced by seismic loading.
Subgrade Preparation and Structural Fill
In general, the excavation for the foundation must be level and uniform and continue down to the Poorly
Graded Gravel with Sand and Cobbles. If any soft spots or undocumented fill are encountered, they will
need to be removed and backfilled with structural fill. The excavation width must extend out from the
footing a minimum distance equal to one footing width or to a distance equal to ½ the height of the required
structural fill; for example, if 6 feet of structural fill is required, the excavation must extend outwards from
the foundation footings a minimum distance of 3 feet.
Structural fill is defined as all fill that will ultimately be subjected to structural loadings, such as those
imposed by footings, floor slabs, pavements, etc. The Poorly Graded Gravel with Sand and Cobbles may
be reused as structural fill, provided any cobbles larger than 6 inches in size are removed. Structural fill
may also be imported for this project, if needed. Imported structural fill is recommended to be a well
graded gravel with sand that contains less than 15 percent of material that will pass a No. 200 sieve and
that has a maximum particle size of 3.0 inches. Also, the fraction of material passing the No. 40 sieve shall
have a liquid limit not exceeding 25 and a plasticity index not exceeding 6. The gravel and sand particles
also need to be made up of durable rock materials that will not degrade due to moisture or the compaction
effort; i.e. no shale or mudstone fragments should be present.
Structural fill must be placed in lifts no greater than 12-inches (uncompacted thickness) and be uniformly
compacted to a minimum of 97 percent of its maximum dry density, as determined by ASTM D698.
Typically, the structural fill must be moisture conditioned to within + 2 percent of the materials optimum
moisture content to achieve the required density. It is recommended that the structural fill be compacted
with a large vibrating smooth drum roller. Please note that if a moisture-density relationship test
(commonly referred to as a proctor) needs to be performed for a proposed structural fill material to
determine its maximum dry density in accordance with ASTM D698, a sample of the material must be
delivered to this office a minimum of three full working days prior to density testing being needed.
Jonathan Stites – Geotechnical Investigation
February 25, 2025 Page 7 of 12
At no time should surface water runoff be allowed to flow into and accumulate within the excavation for
the foundation elements. If necessary, a swale or berm should be temporarily constructed to reroute all
surface water runoff away from the excavation. Excavation should not proceed during large precipitation
events.
If any of the foundation footings are found to be located on a test pit, the area will need to be excavated
down to the full depth of the test pit and structural fill be placed and compacted in controlled lifts as
described in this report to bring the area back up to the desired grade.
Foundation Wall Backfill
Approved backfill material should be placed and compacted between the foundation wall and the edge of
the excavation. The organic soil shall not be used as foundation wall backfill. The Lean Clay, Poorly Graded
Gravel with Sand and Cobbles and Undocumented Fill encountered during the field investigation are all
suitable for reuse as foundation wall backfill along the exterior of the foundation in areas that will not have
concrete or asphalt pavements, provided they are not too moist and any cobbles larger than 6 inches in
size are removed. Structural fill is recommended as foundation wall backfill in all areas that will support
concrete slabs-on-grade or asphalt paving improvements.
The foundation wall backfill shall be placed in uniform lifts and be compacted to a minimum of 95 percent
of the material’s maximum dry density, as determined by ASTM D698. The foundation wall backfill will
need to be compacted with either walk behind compaction equipment or hand operated compaction
equipment in order to avoid damaging the foundation walls. If walk behind compaction equipment is used
lifts should not exceed 8-inches (loose thickness) and if hand operated compaction equipment is used lifts
should not exceed 4-inches (loose thickness).
Interior Slabs-on-Grade
For any interior slabs-on-grade, it is recommended that the excavation continue down through the
Undocumented fill, Organic soil and Lean Clay to the Poorly Graded Gravel with Sand and Cobbles or to a
depth of 6 inches below the proposed bottom of slab elevation, whichever is deeper. If needed structural
fill can then be placed and compacted to within 6 inches of the bottom of slab elevation.
For all interior concrete slabs-on-grade, preventative measures must be taken to stop moisture from
migrating upwards through the slab. Moisture that migrates upwards through the concrete slab can
damage floor coverings such as carpet, hardwood and vinyl, in addition to causing musty odors and mildew
growth. Moisture barriers will need to be installed to prevent water vapor migration and capillary rise
through the concrete slab.
Capillarity is the result of the liquid property known as surface tension, which arises from an imbalance of
cohesive and adhesive forces near the interface between different materials. With regards to soils, surface
Jonathan Stites – Geotechnical Investigation
February 25, 2025 Page 8 of 12
tension arises at the interface between groundwater and the mineral grains and air of a soil. The height of
capillary rise within a given soil is controlled by the size of the pores between the soil particles and not the
size of the soil particles directly. Soils that have small pore spaces experience a higher magnitude of
capillary rise than soils with large pore spaces. Typically, soils composed of smaller particles (such as silt
and clay) have smaller pore spaces.
In order to prevent capillary rise through concrete slabs-on-grade it is recommended that 6 inches of ¾-
inch washed rock (containing less than 10 percent fines) be placed and compacted once the excavation for
the slab is complete. The washed rock has large pore spaces between soil particles and will act as a
capillary break, preventing groundwater from migrating upwards towards the bottom of the slab.
Water vapor is currently understood to act in accordance with the observed physical laws of gases, which
state that the water vapor will travel from an area of higher concentration to that of a lower concentration
until equilibrium is achieved. Because Earth contains large quantities of liquid water, water vapor is
ubiquitous in Earth’s atmosphere, and, as a result, also in soils located above the water table (referred to
as the vadose zone). Typically, the concentration of water vapor in the vadose zone is greater than that
inside the residence. This concentration difference may result in an upward migration of water vapor from
the vadose zone through the concrete slab-on-grade and into the building.
In order to prevent this upward migration of water vapor through the slab, it is recommended that a 15-mil
extruded polyolefin plastic that complies with ASTM E1745 (such as a Stego Wrap 15-mil Vapor Barrier)
be installed. The vapor barrier should be pulled up at the sides and secured to the foundation wall or footing.
Care must be taken during and after the installation of the vapor barrier to avoid puncturing the material,
and all joints are to be sealed per the manufacture’s recommendations.
Once the excavation for any interior slabs-on-grade is completed as described in the first paragraph of this
section, and the ¾ inch washed rock and moisture barriers have been properly installed, it will be
acceptable to form and cast the steel reinforced concrete slab. It is recommended that interior concrete
slabs-on-grade have a minimum thickness of 4 inches, provided the slab reinforcement is designed by a
licensed structural engineer.
Exterior Slabs-on-Grade
For exterior areas to be paved with concrete slabs such as sidewalks and/or patios, it is recommended
that, at a minimum, the Undocumented Fill and Organic Soil be removed. The subgrade then needs to be
compacted to a minimum of 95 percent of its maximum dry density, as determined by ASTM D698. Then
for non-vehicular traffic areas, a minimum of 6 inches of ¾-inch minus rock needs to be placed, and 4
inches of 4000 pounds per square inch (psi) concrete placed over the ¾-inch minus rock. For areas with
vehicular traffic, a minimum of 9 inches of ¾-inch minus rock should be placed, followed by 6 inches of
4000 psi concrete.
Jonathan Stites – Geotechnical Investigation
February 25, 2025 Page 9 of 12
Exterior slabs that will be located adjacent to the foundation walls need to slope away from the structure
at a minimum grade of 2 percent and should not be physically connected to the foundation walls. If they
are connected, any movement of the exterior slab will be transmitted to the foundation wall, which may
result in damage to the structure.
Site Grading
Surface water should not be allowed to accumulate and infiltrate the soil near the foundation. Proper site
grading will ensure surface water runoff is directed away from the foundation elements and will aid in the
mitigation of excessive settlement. Please find the following as general site grading recommendations:
Finished grade must slope away from the building a minimum of 5 percent within the first 10 feet,
in order to quickly drain ground surface and roof runoff away from the foundation walls. Please
note that in order to maintain this slope; it is imperative that any backfill placed against the
foundation walls be compacted properly. If the backfill is not compacted properly, it will settle and
positive drainage away from the structure will not be maintained.
Permanent sprinkler heads for lawn care should be located a sufficient distance from the structure
to prevent water from draining toward the foundation or saturating the soils adjacent to the
foundation or adjacent to any paving improvements.
Rain gutter down spouts are to be placed in such a manner that surface water runoff drains away
from the structure and any paving improvements.
All roads, walkways, and architectural land features must properly drain away from all structures
and paving improvements. Special attention should be made during the design of these features
to not create any drainage obstructions that may direct water towards or trap water near the
foundation or paving improvements.
Asphalt Paving Improvements
For areas to be paved with asphalt, it is recommended that, as a minimum, the Undocumented fill and
Organic Soil be removed. The native subgrade then needs to be compacted at ± 2 percent of its optimum
moisture content to 95 percent of its maximum dry density. Following compaction of the native subgrade
a layer of separation geotextile shall be installed (such as a Mirafi 160N), followed by a 12-inch layer of
compacted 6-inch minus gravel, followed by a 6-inch layer of compacted 1-inch minus road mix. Both
gravel courses must be compacted at ± 2 percent of their optimum moisture content to 95 percent of their
maximum dry density. A 3-inch-thick layer of asphalt pavement can then be placed and compacted over
this cross-section.
It is recommended that following compaction of the native subgrade, a loaded dump truck or other heavy
piece of equipment should be driven over it to determine the stability of the subgrade. If any isolated soft
Jonathan Stites – Geotechnical Investigation
February 25, 2025 Page 10 of 12
spots are found, these areas should be sub-excavated and replaced with compacted fill. If widespread
unstable conditions are present (i.e. significant rutting or pumping is observed) the sub-base component
of the road section will need to be increased and a geotextile may also be required, especially if moisture
related issues are the cause of the instability. In severe cases, geogrid may also be required.
If asphalt paving is to be placed on foundation wall backfill, it is imperative that the backfill be compacted
to a minimum of 95 percent of its maximum dry density, as determined by ASTM D698. The backfill must
be placed in uniform lifts and be compacted as described in the foundation wall backfill section of this
report.
Underground Utilities
We recommend specifying non-corrosive materials or providing corrosion protection due to the presence
of clay soils at the site.
It is recommended that ¾-inch minus gravel be used as a bedding material, where bedding material is
defined as all material located within 6 inches of the utility pipe(s). The bedding material should be
thoroughly compacted around all utility pipes. Trench backfill shall be compacted to a minimum of 95
percent of its maximum dry density in paved or landscaped areas and a minimum of 97 percent of its
maximum dry density beneath foundation footings. Backfilling around and above utilities should meet the
requirements of Montana Public Works Standard Specifications.
Construction Administration
The foundation is a vital element of a structure; it transfers all of the structure’s dead and live loads to the
native soil. It is imperative that the recommendations made in this report are properly adhered to. A
representative from IMEG should observe the construction of any foundation or drainage elements
recommended in this report. The recommendations made in this report are contingent upon our
involvement. If the soils encountered during the excavation differ than those described in this report or any
unusual conditions are encountered, our office should be contacted immediately to examine the conditions,
re-evaluate our recommendations and provide a written response.
If construction and site grading take place during cold weather, it is recommended that appropriate winter
construction practices be observed. All snow and ice shall be removed from cut and fill areas prior to site
grading taking place. No fill should be placed on soils that are frozen or contain frozen material. No frozen
soils can be used as fill under any circumstances. Additionally, Concrete should not be placed on frozen
soils and should meet the temperature requirements of ASTM C 94. Any concrete placed during cold
weather conditions shall be protected from freezing until the necessary compressive strength has been
attained. Once the footings are placed, frost shall not be permitted to extend below the foundation
footings, as this could heave and crack the foundation footings and/or foundation walls.
Jonathan Stites – Geotechnical Investigation
February 25, 2025 Page 11 of 12
It is the responsibility of the contractor to provide a safe working environment with regards to excavations
on the site. All excavations should be sloped or shored in the interest of safety and in accordance with
local and federal regulations, including the excavation and trench safety standards provided by the
Occupational Safety and Health Administration (OSHA).
Report Limitations and Guidelines for Use
This report was prepared to be used exclusively by Jonathan Stites for commercial improvements to be
constructed on Lots 4-6, Block 20 of the Baxter Meadows Subdivision Phase 2A in Bozeman, Montana. All
of the work was performed in accordance with generally accepted principles and practices used by
geotechnical engineers and geologists practicing in this or similar localities. This report should not be used
by anyone it was not prepared for, or for uses it was not intended for. Field investigations and preparation
of this report was conducted in accordance with a specific set of requirements set out by the client, which
may not satisfy the requirements of others. This report should not be used for nearby sites or for structures
on the same site that differ from the structures that were proposed at the time this report was prepared.
Any changes in the structures (type, orientation, size, elevation, etc.) proposed for this site must be
discussed with our company for this report to be valid.
The recommendations made in this report are based upon data obtained from test pits excavated at the
locations indicated on the attached Test Pit Location Map. It is not uncommon that variations will occur
between these locations, the nature and extent of which will not become evident until additional
exploration or construction is conducted. These variations may result in additional construction costs, and
it is suggested that a contingency be provided for this purpose. If the soils encountered during the
excavation differ than those described in this report or any unusual conditions are encountered, our office
should be contacted immediately to examine the conditions and re-evaluate our recommendations and
provide a written response. This report is valid as a complete document only. No portion of this report
should be transmitted to other parties as an incomplete document. Misinterpretation of portions of this
report (i.e. test pit logs) is possible when this information is transmitted to others without the supporting
information presented in other portions of the report.
The scope of our investigation did not include an environmental assessment for determining the presence
or absence of hazardous or toxic materials on the site. If information regarding the potential presence of
hazardous materials on the site is desired, please contact us to discuss your options for obtaining this
information. If any questions arise with regards to any aspects of this report, please contact us at your
convenience to avoid misinterpretation. Costly mistakes due to misinterpretation of geotechnical reports
can usually be avoided by a quick phone call. If you have any questions or if you need further assistance
with your project, please contact the undersigned.
GC
OL
CL
GP
0.8
2.0
4.5
6.5
0 TO 0.83 FEET: UNDOCUMENTED FILL; (GP-GC); dark brown; moist; soft.
0.83 TO 2 FEET: ORGANIC SOIL; (OL); black; moist; very soft.
2 TO 4.5 FEET: LEAN CLAY; (CL); tan to grayish white; moist to very moist; very moist and
gleyed starting at a depth of 3.0 feet..
4.5 TO 6.5 FEET: POORLY GRADED GRAVEL WITH SAND AND COBBLES; (GP); dark
brown; moist to saturated.
Bottom of test pit at 6.5 feet.
NOTES
GROUND ELEVATION
LOGGED BY Michael J. Welch, P.E.
EXCAVATION METHOD Bobcat E88
EXCAVATION CONTRACTOR Elevation Excavating GROUND WATER LEVELS:
DATE STARTED 10/24/24 COMPLETED 10/24/24
AT TIME OF EXCAVATION 6.50 ft
AFTER EXCAVATION ---
AT END OF EXCAVATION ---DEPTH(ft)0.0
2.5
5.0 SAMPLE TYPENUMBERPAGE 1 OF 1
TEST PIT NUMBER TP1
PROJECT NUMBER 24006453.00
CLIENT Jonathan Stites
PROJECT LOCATION Lots 4-6 Blk 20 Baster Meadows PH 2A
PROJECT NAME Geotechnical Investigation
GENERAL BH / TP / WELL - GINT STD US.GDT - 2/24/25 12:15 - \\FILES\ACTIVE\PROJECTS\2024\24006453.00\DESIGN\CIVIL\GEOTECHNICAL\TEST PIT LOGS.GPJU.S.C.S.GRAPHICLOGMATERIAL DESCRIPTION
GC
OL
CL
GP
1.0
2.2
4.8
6.8
0 TO 1 FEET: UNDOCUMENTED FILL; (GP-GC); dark brown; moist; soft.
1 TO 2.2 FEET: ORGANIC SOIL; (OL); black; moist; very soft.
2.2 TO 4.83 FEET: LEAN CLAY; (CL); tan to grayish white; moist to very moist; very moist
and gleyed starting at a depth of 3.0 feet..
4.83 TO 6.83 FEET: POORLY GRADED GRAVEL WITH SAND AND COBBLES; (GP); darkbrown; moist to saturated.
Bottom of test pit at 6.8 feet.
NOTES
GROUND ELEVATION
LOGGED BY Michael J. Welch, P.E.
EXCAVATION METHOD Bobcat E88
EXCAVATION CONTRACTOR Elevation Excavating GROUND WATER LEVELS:
DATE STARTED 10/24/24 COMPLETED 10/24/24
AT TIME OF EXCAVATION 6.83 ft
AFTER EXCAVATION ---
AT END OF EXCAVATION ---DEPTH(ft)0.0
2.5
5.0 SAMPLE TYPENUMBERPAGE 1 OF 1
TEST PIT NUMBER TP2
PROJECT NUMBER 24006453.00
CLIENT Jonathan Stites
PROJECT LOCATION Lots 4-6 Blk 20 Baster Meadows PH 2A
PROJECT NAME Geotechnical Investigation
GENERAL BH / TP / WELL - GINT STD US.GDT - 2/24/25 12:15 - \\FILES\ACTIVE\PROJECTS\2024\24006453.00\DESIGN\CIVIL\GEOTECHNICAL\TEST PIT LOGS.GPJU.S.C.S.GRAPHICLOGMATERIAL DESCRIPTION
GC
OL
CL
GP
1.3
2.4
5.0
7.3
0 TO 1.25 FEET: UNDOCUMENTED FILL; (GP-GC); dark brown; moist; soft.
1.25 TO 2.41 FEET: ORGANIC SOIL; (OL); black; moist; very soft.
2.41 TO 5 FEET: LEAN CLAY; (CL); tan to grayish white; moist to very moist; very moistand gleyed starting at a depth of 3.5 feet..
5 TO 7.33 FEET: POORLY GRADED GRAVEL WITH SAND AND COBBLES; (GP); dark
brown; moist to saturated.
Bottom of test pit at 7.3 feet.
NOTES
GROUND ELEVATION
LOGGED BY Michael J. Welch, P.E.
EXCAVATION METHOD Bobcat E88
EXCAVATION CONTRACTOR Elevation Excavating GROUND WATER LEVELS:
DATE STARTED 10/24/24 COMPLETED 10/24/24
AT TIME OF EXCAVATION 7.33 ft
AFTER EXCAVATION ---
AT END OF EXCAVATION ---DEPTH(ft)0.0
2.5
5.0 SAMPLE TYPENUMBERPAGE 1 OF 1
TEST PIT NUMBER TP3
PROJECT NUMBER 24006453.00
CLIENT Jonathan Stites
PROJECT LOCATION Lots 4-6 Blk 20 Baster Meadows PH 2A
PROJECT NAME Geotechnical Investigation
GENERAL BH / TP / WELL - GINT STD US.GDT - 2/24/25 12:15 - \\FILES\ACTIVE\PROJECTS\2024\24006453.00\DESIGN\CIVIL\GEOTECHNICAL\TEST PIT LOGS.GPJU.S.C.S.GRAPHICLOGMATERIAL DESCRIPTION
REVISIONS DATE DESCRIPTION No 1143 STONERIDGE DRIVE, SUITE 1 BOZEMAN, MONTANA JONATHAN STITES LOTS 4-6, BLOCK 20 BAXTER MEADOWS PHAE SA BOZEMAN, MONTANA TEST PIT LOCATION MAP IMEG No. 24005453.00 Drawn By: MJW Checked By: Date: 2.25.2025 A-1 Sheet 1 of 1 N Map Source: Google Earth