HomeMy WebLinkAbout20A Geotech Report - Part 1 Geotechnical Investigation Report
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Client: The Lakes at Valley West Bozeman, LLC
P.O. Box 1113
Suite 179
Bozeman, Montana 59715
Project: The Lakes at Valley West Bozeman, Montana
Gallatin County
CR Project No: 014095CR
Date: October 17th, 2014
Introduction
The purpose of this report is to serve as a record of geotechnical information obtained through research,
observations, and laboratory testing for the above referenced project. Preliminary recommendations made within
are based upon this information as well as experience with similar projects in the area. The geotechnical
information presented within this report is to be used by the Client to make educated decisions regarding the
development of the subdivision. Recommendations for subgrade improvements of individual lots are subject to
change based on grade and soil conditions observed at the time of home construction.
Site Information
The property is a total of 63.6 acres and is situated between Aajker Creek on the west property boundary and
Baxter Creek along the east property boundary. There are two large ponds centrally located on the property that
each have a longitudinal axis exceeding 500-ft.
Figure 1 – Vicinity and Topographic Map circa 1987
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The vicinity map, topographic map, and legal description are given in Figure 1. The ponds do not appear on the
topographic map shown because they were constructed after its publishing.
Utilizing Google Earth’s geobrowser, chronological aerial images show that previously there was one large pond.
Between 2006 and 2009, earthwork activities created two ponds with a road constructed between them. Due to
the significant amount of earthwork performed on the property, the current topography differs greatly than the
1980’s topographic map shown in Figure 1. There are currently large berms along the north boundary of the
property and several large stockpiles of topsoil and gravels on the south portion of the property.
Definitions
To assist the reader in understanding site conditions at a point in time, several definitions have been prepared.
The terms include pre-development, development, and post-development grades. Other important terms and
definitions are listed below.
Pre-development grade: The topography of the property as observed during this investigation, prior to installation
of infrastructure or commencement of additional earthwork activities.
Specifically, this includes large berms located along the north side, low spots along the west side, and large
stockpiles of topsoil and gravels along the south boundary. The east side of the property is nearly the natural
topography with minimal disturbance to the ground. The attached soil bore logs are reflective of the pre-
development grade.
Development grade: The topography of the property after installation of infrastructure and general earthwork
activities.
Post-Development grade: The grades of the ground after homes are constructed and backfilled on a property.
Overburden/Spoils: Soils that are disturbed by construction activities; including soils that have been placed upon
undisturbed ground surfaces. Examples for this site are soils consisting of dark brown silt loam with organics, dark
brown sandy gravels, mottled silt, clay loam, and non-plastic sandy gravels.
Topsoil: Native soil material consisting of dark brown silt loam with a high amount of organics; usually undisturbed
ground’s first soil horizon. Topsoil remnants have been observed under spoils across the property.
Development Design: Recommendations pertaining to earthwork activities for the benefit of the Developer to
achieve development grade.
Lot subgrade improvements: Geotechnical recommendations given regarding the development of each residential
lot for the benefit of the Builder.
Structural Fill: Soil upon which structural elements such as footings, sonotubes, slabs, etc. may be constructed
upon. Two different types of material may be used as structural fill: mined on-site 4-inch minus pit run gravels
with no clay or less than 10% non-plastic fines; or imported 3-inch minus (well graded) pit run gravels with less
than 10% non-plastic fines.
Building footprint: The entire heated area of the house including covered porches.
Excavation footprint: The building footprint plus an additional 3-feet horizontal around the perimeter of the
building footprint.
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Site Research
Montana Bureau of Mines and Geology (MBMG)
Montana Bureau of Mines and Geology (MBMG) record the geological formation of the property as Qafo –
Alluvial-fan deposits, older than Qaf (Pleistocene). An alluvial fan is defined as an outspread, gently sloping mass
of alluvium deposited by a stream, esp. in an arid or semiarid region when a stream issues from a narrow canyon
onto a plain or valley floor. Viewed from above, it has the shape of an open fan, the apex being at the valley mouth
(Bates, 1984). Alluvium is material deposited by a stream or running water.
Figure 2 – MBMG Geological Map
Natural Resources Conservation Service (NRCS)
The Natural Resources Conservation Service (NRCS) records multiple soil units for the project. Suitability ratings
for dwellings with basements and without basements, risk of corrosion to both concrete and steel, and water
features reports can be found in the attachments. The majority of the soils mapped on-site have a high or
moderate risk for corrosion to steel. Therefore, buried metal is to be either stainless steel, epoxy coated, encased
in polyethylene wrap or have cathodic protection. Several of the soils on site have a moderate risk of corrosion to
concrete. All of the soil units mapped across the site have a parent material that is either loamy alluvium or
alluvium associated with stream terraces or alluvial fans.
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Figure 3 – NRCS Soil Units (See attached NRCS Data for more information)
Linear extensibility is a measurement of a soil’s shrink-swell potential and is considered low if the linear
extensibility is less than 3 percent, moderate for 3 to 6 percent, high if 6 to 9 percent, and very high if more than 9
percent. If linear extensibility is more than 3, shrinking and swelling can cause damage to buildings, roads, and
other structures. For the assigned soil units, the linear extensibility varies from 0.00 up to 5.9 depending on the
soil unit. It is recommended that the geotechnical engineer observe all newly exposed grounds at the time of
construction to determine if potentially sensitive soils exist in the area of interest. All soil units except units 448A
and 748A were listed on the NRCS National List of Hydric Soils under “Criterion 2”.
Groundwater
This is not a long term groundwater study; however, structural damage may occur when groundwater is not
considered during the design process. Groundwater is “loosely” defined by The American Geologic Institute as “all
subsurface water as distinct from surface water.” In this report, the term groundwater is to be reserved for large
water tables over reasonably large areas and basins, not to be confused with small weeps near the surface due to
surface waters. Groundwater is defined within this report to describe water in the ground that is much more
permanent, consistent, and uniform, not subject to change quickly in a short period of time or over a short
distance. Near surface conditions change quickly and will not remain constant across this site. Our opinion,
though conservative, prevents misinterpretation and better defines conditions.
Montana Groundwater Information Center (GWIC) Well Log ID 190942 is located in the vicinity. The soil profile
recorded for this well log consists of 3-feet of topsoil underlain by clay gravel that continued to 42-feet below
ground surface. From 42-feet to 60-feet, there was a horizon of clay. Static water was recorded at 3-feet below
ground surface.
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Groundwater located at or above the assumed foundation footing grade can impact foundation performance. It is
recommended that at least 2-feet separation is maintained between bottom of footing and groundwater elevation
for typical 16- or 18-inch wide footings. Groundwater was observed in most of the test holes excavated during the
geotechnical investigation. It was noted that groundwater appeared to equalize with the elevation of the ponds in
one test hole overnight. Groundwater monitoring wells have been installed to document peak run off but it can be
assumed that the ponds are reliable indicators of the depth to groundwater. Groundwater levels are shown in the
Soil Logs found in the Attachments at the end of this report. Groundwater monitoring is ongoing.
Geotechnical Investigation
A geotechnical investigation was performed on September 9th and 10th, 2014 by Andy Pilskalns, P.E. and Danae
Bray, E.I. of Castle Rock Geotechnical Engineering (CRGE). Mike Cooper and Cody Sabo of SIME were present to
operate equipment. Fifteen test holes were excavated across the property; see the Test Hole Maps in the
Attachments. The depth of the test holes varied from one to twelve feet. The location of the test holes were
determined by either the Client or CRGE. Generalization of the test holes are made within the report; see attached
bore logs and test hole maps for data pertaining to each test hole. Approximate test hole locations were
superimposed on an aerial image from 2005 to verify approximate previous cut and fill areas, see attached Test
Hole Map (2005).
Soils were visually classified utilizing the Unified Soils Classification System (USCS). The native soil profile consists
of dark brown silt loam topsoil with organics, USCS Symbol OL-ML, underlain by tan clay loam, USCS Symbol CL,
which was underlain by poorly graded native sandy gravels, USCS Symbol GP. The thickness of each horizon varied
but typically, the native gravels were at approximately 5-feet below the “native” ground surface. In several
locations across the site, spoils have been placed upon the native ground surface. In these areas, the depth to
native gravels is equal to the height of the undisturbed soils in addition to the height of the spoils. The native
sandy gravels are excellent load bearing material. In most cases, groundwater is found where the native sandy
gravel horizon is observed.
Imported fill material was observed in test holes excavated along the north and west portion of the property. The
fill material was found to be non-uniform and varied between silty loam, clay loam, and poorly graded gravels.
Some plastic and wood debris was also observed in this fill material. The depth of fill varied and it is recommended
that each lot is observed by the geotechnical engineer to determine how much imported fill has been placed. Test
hole depths were determined by the depth to groundwater. Groundwater was observed as shallow as 2-feet
below ground surface on the south end of the lot to 12-feet below ground surface on the north end of the lot. This
variation in elevation is due to the additional imported fill being placed on the north side of the property.
Laboratory Results
Samples were obtained from TH-14 located in the northwest portion of the property and from the stockpile of
gravels located on the south side of the property. One undisturbed thin-walled shelby tube sample and one bulk
sample was taken from TH-14 while two bulk samples were taken of the gravel stockpile.
The following testing procedures as established by the American Society of Testing & Materials (ASTM) were used:
Atterberg..........................................................ASTM D 4318
Proctor……………………………………………………..……ASTM D 698-07 Method A
Organic Content by Loss on Ignition………………ASTM D 2974
One Dimensional Consolidation Test……………..ASTM D 2435/D 2435M
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The Atterberg Limits Tests are three individual tests used to define soil characteristics. The tests are the Liquid
Limit Test (LL), the Plastic Limit Test (PL), and the Shrinkage Limit Test (SL). The Plasticity Index (PI) is defined as
the liquid limit minus the plastic limit and is used to categorize the sample as well as define strength parameters.
Table 1 – Sample Results
Sample
Location Liquid Limit Plasticity Index % Organic
Matter
USCS Symbol
TH-14 46 20 5.6 CL
O’Neill and Poormoayed, Army Corp of Engineers 1980, developed an expansive soils classification which is
summarized in Table 2. The limits indicate that the soil tested from the site have a low swell potential. The
amount of water within the soils needs to be near 46% for the soils to begin exhibiting liquid characteristics. This
amount is significantly greater than the amount found in the soils during the investigation. However, from
experience, the moisture content in the soils can increase significantly during spring runoff. Additionally, one
sample cannot be considered representative for the entire site. Soils with a slightly higher plasticity index have a
moderate swell classification and would be considered unsuitable for constructing upon.
Table 2 – Swell Classification
Liquid Limit Plasticity Index Swell (%) Classification
< 50 < 25 < 0.5 LOW
50 TO 60 25 - 35 0.5 – 1.5 MARGINAL
> 60 > 35 > 1.5 HIGH
Potential Swell = Vertical swell under the pressure equal to the overburden pressure
Summary of Research & Investigation
Observations completed during the geotechnical investigation correlate well with information published by the
NRCS and MBMG for this property. Additionally, historical aerial photographs confirm the areas of fill as once
being low spots or ponds. Overall, the depth to good load bearing gravels is favorable for development.
Additional auger drilling is recommended for grounds on the west side of the west pond that consist of gravel fill.
Due to the uncertainty about the fill, additional information will be needed. Drilling is recommended to ascertain
that imported fill has been properly placed and is both continuous and suitable for development.
Development Design
A site map divided into eight phases of development was provided to CRGE by the Developer. Development
Design and Geotechnical recommendations are given for the development of property to transition from pre-
development grade to development grade and finally to post-development grade. Figure 4 shows the eight phases
of planned development which in some cases, such as Phase 7, have been sub-divided to better delineate a
boundary. The recommendations given within are based on field observations and by utilizing the USGS
topographic map prepared with 20 foot contours. Discrepancies may exist concerning actual grades and elevations
from what has been generalized by field observations. The Developer plans on preparing current topographic
surveys for the property prior to development. It is recommended that we review the survey to ensure no large
discrepancies exist that may affect the proposed development design. Although an effort has been made to gain
greater understanding of the subsurface conditions across the property, it must be understood that not all
subsurface soils or conditions will be known until the site is unearthed.
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During the field investigation, the following observations were made: The properties within phase 1, 2, & 3 had
overburden/spoils placed upon the (undisturbed) native ground surface. Phase 4 can be generalized as being
several feet lower in elevation than Phases 1, 2, & 3. Phase 7 is divided into two sections as the west half, denoted
as 7W and the east half, denoted as 7E. The ground elevation of 7W is lower than 7E. Imported fill was observed
in the excavated test hole TH-6 within Phase 7E. The imported fill is sandy gravels used to backfill the pond. The
extent of this fill material that was used in this vicinity was not determined. Therefore, it is recommended that
subgrade improvement recommendations for Phase 7E be considered independently of the surrounding phases
until further study is completed at a later time. Groundwater is very shallow in Phases 4, 7W, & 8 and therefore,
dewatering is recommended in these areas prior to modifying the pre-development grade. It is anticipated that
dewatering may not be necessary in Phases 1, 2, & 3. However, if groundwater becomes a problem, it must be
controlled so that it does not adversely affect earthwork activities. It is the responsibility of the Contractor to plan
and control all dewatering activities including permitting.
Figure 4- Geotechnical Recommendations for Development Organized by Phases
To prepare the property for development, it is recommended that Phases 1, 2, & 3 are first cleared of all
overburden/spoils. These soils may be stockpiled in Phases 4, 7W, & 8 only after the stockpile locations are
properly prepared. Stockpile sites in Phase 4, 7W, & 8 are to be dewatered and stripped of topsoil clay and
organics before placing spoils. Therefore, when the overburden is removed, the grounds will then be at
development grade with no additional work required. This will prevent reworking and moving spoils as little as
possible. It is recommended that spoils consisting of topsoil or having high amounts of organics be stockpiled
separately from non-organic fill.
Once the overburden has been removed from Phases 1, 2, & 3, this portion of the property can be prepared for
development according to the subgrade improvement recommendations given below. Phases 4, 7W, & 8 (low
areas), as mentioned above, will require dewatering prior to earthwork activities and stripping of the ground.
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Once the groundwater has been lowered in these areas, it is recommended that all organics and topsoil material is
removed. The Geotechnical Engineer is to be contacted to observe the ground conditions prior to covering with
spoils. Once the grounds have been approved by the Geotechnical Engineer, the overburden removed from Phase
1, 2, & 3 can be placed across Phase 4, 7W, & 8, as needed, so that the elevation of the low areas match
development grade of Phases 1, 2 & 3. In our opinion, based on existing grade, the development grade for Phases
5 & 6 will require minimal earthwork. Dewatering will be necessary for deeper excavation and installation of
utilities.
The previously discussed areas of cut and fill are to be stabilized through seeding of native vegetation or sodding to
prevent erosion. Stockpiled topsoil may be placed upon non-organic fill in areas that will not be constructed upon.
Development Design recommendations are not necessarily based on the currently planned chronological order of
development but rather based upon what is perceived to be the most efficient use of time and materials. It is
understood that developed will occur over time. It is recommended that despite the amount of time between
completing a particular phase that the Development Design recommendations are adhered to in the given
sequence of events.
Roadway Recommendations
All roadway areas are to be stripped of organics and topsoil and vertically over-excavated 24-inches. The area is to
then be made level, smooth, and compacted utilizing a 54 inch wide smooth drum compactor. The compacted
ground is to be covered with a continuous sheet of Mirafi 500X geotextile with 3-feet overlap end-to-end. Once
the geotextile is in place, it can be coved with 18-inches of base material defined as 6 inch minus pit run gravels
containing less than 10% non-plastic fines. On-site mined pit run gravels may be used as sub-base upon approval
by the Geotechnical Engineer. The pit run is to be compacted to 95% of the materials maximum dry density and +
1.5% of optimum moisture as determined by method ASTM D-698. The pit run is to be covered by 3 inches of
crushed base defined as 1 inch minus pit run gravels which is properly compacted. Finally, 3 inches of Hot Plant
Mix surface course is to be paced upon the compacted base.
Figure 5 – Typical Roadway Section
For areas in which native sandy gravels are within 24-inches of the existing ground surface, such as around the
southern portion of the property, the typical roadway section is not required. For shallow depths to native sandy
gravels or areas where sandy gravels are the ground surface it is recommended that the ground surface is stripped
of all overlying organics and topsoil and the native gravels are proofed rolled. The Geotechnical Engineer is to
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observe and approve the newly exposed ground. Once approved, 6-inch minus pit run gravels can be placed
within 6-inches of the final roadway grade. Once the sub-base has been properly placed, moisture conditioned,
and compacted, the recommendations pertaining to the crushed base and surface course, as shown in Figure 5,
are to be implemented. It is recommended that the Geotechnical Engineer is contacted to compliance test all
roadway material. If groundwater is an issue during road construction dewatering will be necessary.
Lot Subgrade Improvement Recommendations
Each lot is to be observed by the Geotechnical Engineer that prepared this report to verify conditions and revise
recommendations as necessary. It is the responsibility of the Builder to schedule site visits by the Engineer during
lot development.
Under no circumstance are structural or critical architectural elements such as footings, piers, sono-tubes, slabs
etc. to be constructed upon non-approved grounds, non-structural fill, topsoil, or clay soil. Critical architectural
elements outside of the structure will require alternative subgrade improvement consideration. Please plan the
designs with the Geotechnical Engineer.
The general allowable bearing capacity of the footings for single and two story buildings constructed upon
approved (by the Geotechnical Engineer) native well-graded sandy gravels or properly placed imported well-
graded pit run gravels (as define within this report) is 2,500 lb/ft2. The general allowable bearing capacity is based
on groundwater being a minimum 3 feet below bottom of footing.
The minimum footing dimensions, depth x width, for a two-story residential building is 8” x 18” and for a single
story residential building is 8” x 16”. For footing and stem wall type foundations, the bottom of the footing as
required by Montana State Code is to be protected by 4 feet of cover for 2-story buildings. The recommendations
include all critical architectural elements such as sono tubes, columns, piers and slabs unless some alternative
design consideration has been made.
Two types of foundations are recommended. A typical crawl-space type foundation is shown in Figure 6. If this
type of foundation is used, it is recommended that a sump pump and all related appurtenances are installed within
the crawl space to mitigate issues with groundwater. A typical concrete stem-wall with slab on grade is shown in
Figure 7. Under no circumstances are footings or other structural elements to be constructed upon material other
than structural fill or approved native gravels. Furthermore, structural fill must be used on the interior side of the
walls and placed within 12-inches of the height of exterior fill material being placed.
All structural fill is to be moisture conditioned to + 3% of the materials optimum moisture content. When using
structural fill, it must be free of clay or contain less than 10 % non-plastic fines. The Contractor will be responsible
referencing the attached laboratory tests which determine the maximum dry unit weight and optimum moisture
content of the “mined on site 4-inch minus pit run gravels” to be used as structural fill.
All fill is to be placed to the prescribed specifications given within. The Geotechnical Engineer is to be contacted
immediately if the ground is too wet to place and compact the imported structural fill. In areas with high
groundwater, it may be deemed appropriate to dewater and place 12 inches of 1-inch minus washed rock upon
the wet “in situ” gravels to create a moisture break before covering with pit run gravels. The 1 inch washed rock in
this case will be considered structural fill that will act as a vapor break so that structural fill can be placed upon the
gravels and compacted without liquefying the structural fill.
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Figure 6 – Foundation Plan – Typical Stem Wall with Crawl-Space
Figure 7 – Foundation Plan – Typical Stem Wall with Slab-on-Grade
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It is recommended that a minimum 18-inches of structural fill be placed upon the “in situ” gravels. For this report,
“in situ gravels” means native undisturbed gravels. In other words, it is recommended that all the topsoil and clay
over the native gravels be removed. The native gravels are to be compacted and then the entire excavation
footprint is to be brought up to grade with at least 18-inches of structural fill. The amount of fill is given as 18
inches but this can vary depending on height of finished floor above curb and other factors. It is recommended
that footings are not designed to be below the water table. If this is not possible, then the amount of fill may be
adjusted depending on height of the water table. Furthermore, a footing drain, as shown in Figure 7, may or may
not be necessary depending on the height of groundwater; this is to be determined for each individual site by the
Geotechnical Engineer.
The allowable bearing capacity of the footings constructed within groundwater will have to be determined based
on the depth of the bottom of footing below top of high groundwater. The structural engineer can share with our
office the determined linear weight of the building per square foot so that we can aid in determining the footing
size with regard to the water table. Insulating the interior or exterior of the foundation is recommended with 2-
inch thick Dow closed cell blue board, as shown in Figure 6 & 7.
Site Grading
All surfaces around the building site are to be designed such that gravity forces direct runoff away from all sides of
the building area both before and after construction. It is recommended that the building backfill and finished
grade slope away 5% on all sides of the building for a minimum of 20-feet. Upslope grading needs to divert surface
sheet-flow, runoff away from the building sites. All backfilling next to foundation walls is to utilize only hand-
operated tamping equipment to prevent excessive forces from destroying already constructed material. An
impermeable (soil) cap should cover the finished ground prior to the placement of topsoil to prevent the easy
absorption of moisture to the subsurface soils on which the building rests. All organics are to be stripped away
prior to placing any backfill. All on-site and run-on storm water is to be managed so as to not adversely affect the
site and foundation. The site is to be elevated so that the grading plan can be properly implemented.
Earthwork-Construction Materials
Utilizing Army Corp of Engineering tests results, it has been shown that the required density of newly placed fill (or
in this case newly exposed disturbed ground) can be achieved (100% maximum dry density). This is possible if the
pit-run type material is placed in 6-inch lifts or in this case, the ground is track packed then compacted by a smooth
drum vibratory roller (minimum 6 passes) with the vibratory equipment operating between 1-2 mile/hour vibrating
at 1200 vib/min. Large compactive forces are necessary to reduce settlement of the native surfaces and imported
pit run soils. One pass is defined as starting at point A, compacting to point B, and returning to point A. All soft
areas that deflect during compaction are to be removed and replaced with washed rock until firm. The subgrade
improvements will act as a stiff platform on which the building loads will be supported.
The sub-grade improvements are to ensure uniform compaction of materials, reduce settlement effects to within
tolerable limits, and to establish a durable working surface for spring and summer weather conditions. Revisions
to the grading plan that do not match the existing terrain and conditions should be reviewed by a Geotechnical
Engineer prior to submittal.
Application Percent Compaction
Wall Backfill 95
Structural Fill Under Slab 97
Structural Fill Under Footing 98
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The native silt soils are not well suited for engineered fill, and unless otherwise directed by the Geotechnical
Engineer, are not to be used as structural fill. If at any time the Contractor notices an extreme change in one or
more of the constituents that make up the approved structural fill soils, they are to contact the Geotechnical
Engineer immediately.
All newly exposed ground is to be proof rolled with a large high energy smooth drum compactor prior to the
placement of structural fill. Backfill around the foundation walls should not be placed until the slab or concrete
walls are adequately cured. No fill should be placed on “green” concrete. All backfill is to be placed in uniform lifts
no greater than 12 inches loose. The upper backfill around frost walls are to utilize only hand operated tamping
equipment next to the wall. Areas where backfill is used should be compacted to 95% of the material’s optimum
dry density, and lifts should not exceed 12-inches in thickness. Approved engineered fill used under the
foundation slab of the building should be compacted to 97% of the soils maximum dry density as defined by ASTM
D698. The moisture content of the “in situ” soils or imported soils is not to exceed + 3% the soils optimum density.
As mentioned, all structural fill is to be capped with a final 6-inch horizon of frost free material.
No recommendations are to occur on overly saturated ground, soft yielding soils, or over frozen soils. Severe
weather practices are to be adhered to. There are many severe weather practices that the Contractor is to apply if
adverse conditions exist during construction. Such as during the winter, the ground on which the foundation is
constructed must not be allowed to freeze. Construction benchmarks should be reviewed by the Engineer and
Architect overlooking certain aspects of construction reviewing progress and quality control. All sub-grades need
to be free of debris, ponded water, and all deleterious material. If construction takes place during the winter
months, good winter construction practices are to be adhered to.
The term "net bearing pressure" is defined as the ultimate pressure per unit area of the foundation that can be
supported by the soil in excess of the pressure caused by the surrounding soil at the foundation level. This is
assuming that the difference between the unit weight of the footing and the surrounding backfill is negligible. Real
loads are defined as the total of all dead plus frequently applied live loads. Total loads include all dead and live
loads, including seismic forces and wind.
Lastly, all rain gutter downspouts should discharge minimum 8-feet away from any side of the buildings. All
finished site grading should allow freestanding water to drain away from the building. Impermeable soils should
be used as finished cover (backfill) prior to the placement of topsoil to prevent the easy absorption of precipitation
around the building.
Seismic Consideration
Given the depth to groundwater and the presence of granular material, the property could experience liquefaction
in the event of a seismic event. It is recommended that the geotechnical engineer observe ground conditions
during all phases of earthwork activity to verify conditions and adjust recommendations as necessary. This is so
that the structural engineer may include geotechnical considerations and loading conditions to include protective
measures during the design process. Although no other geological hazards were observed during this
investigation, by keeping the Geotechnical Engineer involved during development additional observations can be
completed.
Based on the results of our sub-surface investigation and review of available geologic information, we anticipate
the upper 100 foot profile will be comprised of sedimentary deposits of stiff silt, sand, clays, or better. Therefore,
we recommend using Site Class "D" (stiff soil profile) as defined by the 2009 International Building Code for design.
Seismic calculations are made in accordance to general procedures as used/defined by the United State Geological
Survey (USGS), American Society of Civil Engineers Chapter 7, (ASCE 7) and 2009 International Building Code, (2009
IBC).
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The intermountain seismic belt is a zone with major ground shaking potential. The Bozeman area and surrounding
mountains are part of this seismic zone. Seismic activity is possible in the Greater Rocky Mountain Region, which
stretches from Canada to Utah with Bozeman in the middle. As mentioned Montana is subject to significant
seismic activity and the study site is located in the Intermountain Seismic Belt (ISB). Two of the largest recorded
earthquakes in the Northern Rocky Mountains occurred in the Centennial Seismic Belt, a part of the ISB. These
were the August 18th, 1959 Hebgan Lake, Montana, earthquake (M - 7.5), and the October 28, 1983 Borah Peak,
Idaho, earthquake (M - 7.3).
Earthquakes are defined by their magnitude and intensity as a quantitative measure of the energy released by the
earthquake. The highest magnitude values measured for any earthquake have been approximately 8.9.
Earthquakes greater than 8 are considered great earthquakes. Earthquake magnitudes are measured
logarithmically; for example, a magnitude 5 earthquake produces 10 times the wave amplitude of an earthquake
of magnitude 4. A moderate event would be an earthquake associated with a 10 percent probability of occurrence
within 50 years, whereas a severe earthquake corresponds to a 10 percent probability in 250 years.
Seismic research is ongoing and recent research has discovered an interesting new phenomenon characteristic of
seismic waves of line faults, super shear shockwaves, which are violent earthquake waves found to lead a P-wave
much like a supersonic envelope that engulfs an object at the onslaught of or reaching the speed of sound. This
information is given as an example to show that understanding of geologic events is continually evolving with
research. Site profile for seismic design is based on Latitude and Longitude.
Based on the latitude and longitude, various spectral response accelerations were obtained from a website offered
by the United States Geological Survey. Based on a 2 percent probability of exceedance in 50 years, the project
location has maximum 1.0 second spectral response acceleration, S1, of 0.214g percent of gravity and maximum
0.2 second spectral response acceleration, SS, of 0.737g.
Conclusion
The successful completion of the geotechnical engineering of this project is dependent on continued professional
geotechnical services to ensure the proper interpretation and intentions of the recommendations herein and to
observe the construction phases of the design (earthwork, foundation, site grading). Castle Rock Geotechnical
Engineering Inc. is not responsible for quality of “Others” work or interpretation of the recommendations,
furthermore no warranty, expressed or implied, is made. The recommendations made are based on the initial
geotechnical input and therefore to ensure that these are properly incorporated into the construction phases a
Geotechnical Engineer should remain involved with the project. This will reduce the potential for misinterpreting
the recommendations. If you have questions please feel free to contact our office at your convenience. I
appreciate the opportunity to work with you. We look forward to completing the compliance testing services of
this project for you.
Sincerely,
ANDY PILSKALNS P.E. / PRESIDENT
PROFESSIONAL GEOTECHNICAL ENGINEER
LICENSED - MONTANA, UTAH, COLORADO, IDAHO, WYOMING & HAWAII,
NEVADA, NORTH DAKOTA
CASTLE ROCK GEOTECHNICAL ENGINEERING INC.
1114 EAST BABCOCK
BOZEMAN, MONTANA 59715
C: (406) 539-8439 O: (406) 586-9533
www.castlerocker.com andy@castlerocker.com
Geotechnical Investigation Report
\\Central-Server1\Public\Jobs\JBS 2014\014095CR\GR - Lakes at Valley West.doc
14
Attachments:
NRCS Soil Data
Soil Bore Logs
Geotechnical Terminology Sheet
Laboratory Test Results
Test Hole Map (2014)
Test Hole Map (2005)
Map Unit Name—Gallatin County Area, Montana
(Lakes at Valley West)
Natural Resources
Conservation Service
Web Soil Survey
National Cooperative Soil Survey
6/2/2014
Page 1 of 350586605058750505884050589305059020505911050592005058660505875050588405058930505902050591105059200490600490690490780490870490960491050491140491230491320491410491500
490600 490690 490780 490870 490960 491050 491140 491230 491320 491410
45° 41' 11'' N 111° 7' 14'' W45° 41' 11'' N111° 6' 32'' W45° 40' 52'' N
111° 7' 14'' W45° 40' 52'' N
111° 6' 32'' WN
Map projection: Web Mercator Corner coordinates: WGS84 Edge tics: UTM Zone 12N WGS84
0 200 400 800 1200Feet
0 50 100 200 300Meters
Map Scale: 1:4,120 if printed on A landscape (11" x 8.5") sheet.
Map Unit Name
Map Unit Name— Summary by Map Unit — Gallatin County Area, Montana (MT622)
Map unit symbol Map unit name Rating Acres in AOI Percent of AOI
448A Hyalite-Beaverton
complex, moderately
wet, 0 to 2 percent
slopes
Hyalite-Beaverton
complex, moderately
wet, 0 to 2 percent
slopes
1.1 1.3%
509B Enbar loam, 0 to 4
percent slopes
Enbar loam, 0 to 4
percent slopes
6.0 7.3%
510B Meadowcreek loam, 0 to
4 percent slopes
Meadowcreek loam, 0 to
4 percent slopes
20.2 24.8%
511A Fairway silt loam, 0 to 2
percent slopes
Fairway silt loam, 0 to 2
percent slopes
1.0 1.2%
537A Lamoose silt loam, 0 to 2
percent slopes
Lamoose silt loam, 0 to 2
percent slopes
16.1 19.7%
748A Hyalite-Beaverton
complex, 0 to 4
percent slopes
Hyalite-Beaverton
complex, 0 to 4
percent slopes
37.3 45.7%
Totals for Area of Interest 81.6 100.0%
Description
A soil map unit is a collection of soil areas or nonsoil areas (miscellaneous areas)
delineated in a soil survey. Each map unit is given a name that uniquely identifies
the unit in a particular soil survey area.
Rating Options
Aggregation Method: No Aggregation Necessary
Tie-break Rule: Lower
Map Unit Name—Gallatin County Area, Montana Lakes at Valley West
Natural Resources
Conservation Service
Web Soil Survey
National Cooperative Soil Survey
6/2/2014
Page 3 of 3
Map Unit Composition
Hyalite and similar soils: 70 percent
Beaverton and similar soils: 20 percent
Minor components: 10 percent
Description of Hyalite
Setting
Landform: Stream terraces, alluvial fans
Down-slope shape: Linear
Across-slope shape: Linear
Parent material: Loamy alluvium
Typical profile
A - 0 to 5 inches: neutral, loam
Bt1 - 5 to 9 inches: neutral, clay loam
Bt2 - 9 to 17 inches: neutral, silty clay loam
2Bt3 - 17 to 26 inches: neutral, very cobbly sandy clay loam
3C - 26 to 60 inches: neutral, very cobbly loamy sand
Properties and qualities
Slope: 0 to 2 percent
Depth to restrictive feature: More than 80 inches
Natural drainage class: Well drained
Capacity of the most limiting layer to transmit water (Ksat):
Moderately high (0.20 to 0.57 in/hr)
Depth to water table: About 48 to 96 inches
Frequency of flooding: None
Frequency of ponding: None
Calcium carbonate, maximum in profile: 5 percent
Available water storage in profile: Low (about 4.4 inches)
Interpretive groups
Farmland classification: Farmland of local importance
Land capability classification (irrigated): 3e
Land capability classification (nonirrigated): 4e
Hydrologic Soil Group: C
Ecological site: Shallow to Gravel (SwGr) 15-19" p.z.
(R044XS354MT)
Description of Beaverton
Setting
Landform: Stream terraces, alluvial fans
Down-slope shape: Linear
Across-slope shape: Linear
Parent material: Alluvium
Typical profile
A - 0 to 5 inches: neutral, cobbly loam
Bt - 5 to 21 inches: neutral, very gravelly clay loam
Bk - 21 to 25 inches: moderately alkaline, very cobbly coarse sandy
loam
Map Unit Description---Gallatin County Area, Montana Lakes at Valley West
Natural Resources
Conservation Service
Web Soil Survey
National Cooperative Soil Survey
6/2/2014
Page 3 of 11
2Bk - 25 to 60 inches: moderately alkaline, extremely cobbly loamy
coarse sand
Properties and qualities
Slope: 0 to 2 percent
Depth to restrictive feature: More than 80 inches
Natural drainage class: Well drained
Capacity of the most limiting layer to transmit water (Ksat):
Moderately high to high (0.57 to 1.98 in/hr)
Depth to water table: About 48 to 96 inches
Frequency of flooding: None
Frequency of ponding: None
Calcium carbonate, maximum in profile: 15 percent
Salinity, maximum in profile: Nonsaline (0.0 to 2.0 mmhos/cm)
Available water storage in profile: Low (about 3.7 inches)
Interpretive groups
Farmland classification: Farmland of local importance
Land capability classification (irrigated): 4s
Land capability classification (nonirrigated): 6s
Hydrologic Soil Group: B
Ecological site: Shallow to Gravel (SwGr) 15-19" p.z.
(R044XS354MT)
Minor Components
Beaverton
Percent of map unit: 5 percent
Landform: Stream terraces, alluvial fans
Down-slope shape: Linear
Across-slope shape: Linear
Ecological site: Shallow to Gravel (SwGr) 15-19" p.z.
(R044XS354MT)
Meadowcreek
Percent of map unit: 5 percent
Landform: Stream terraces
Down-slope shape: Linear
Across-slope shape: Linear
Ecological site: Subirrigated (Sb) 15-19" p.z. (R044XS359MT)
509B—Enbar loam, 0 to 4 percent slopes
Map Unit Setting
Elevation: 4,400 to 6,000 feet
Mean annual precipitation: 15 to 19 inches
Mean annual air temperature: 37 to 45 degrees F
Frost-free period: 90 to 110 days
Map Unit Composition
Enbar and similar soils: 85 percent
Minor components: 15 percent
Map Unit Description---Gallatin County Area, Montana Lakes at Valley West
Natural Resources
Conservation Service
Web Soil Survey
National Cooperative Soil Survey
6/2/2014
Page 4 of 11
Description of Enbar
Setting
Landform: Flood plains
Down-slope shape: Linear
Across-slope shape: Linear
Parent material: Loamy alluvium
Typical profile
A - 0 to 22 inches: neutral, loam
Cg - 22 to 49 inches: moderately alkaline, sandy loam
2C - 49 to 60 inches: moderately alkaline, very gravelly loamy sand
Properties and qualities
Slope: 0 to 4 percent
Depth to restrictive feature: More than 80 inches
Natural drainage class: Somewhat poorly drained
Capacity of the most limiting layer to transmit water (Ksat):
Moderately high to high (0.57 to 1.98 in/hr)
Depth to water table: About 24 to 42 inches
Frequency of flooding: Rare
Frequency of ponding: None
Calcium carbonate, maximum in profile: 10 percent
Salinity, maximum in profile: Nonsaline (0.0 to 2.0 mmhos/cm)
Available water storage in profile: Moderate (about 8.8 inches)
Interpretive groups
Farmland classification: All areas are prime farmland
Land capability classification (irrigated): 3w
Land capability classification (nonirrigated): 3w
Hydrologic Soil Group: C
Ecological site: Subirrigated (Sb) 15-19" p.z. (R044XS359MT)
Minor Components
Nythar
Percent of map unit: 10 percent
Landform: Flood plains
Down-slope shape: Linear
Across-slope shape: Linear
Ecological site: Wet Meadow (WM) 15-19" p.z. (R044XS365MT)
Straw
Percent of map unit: 5 percent
Landform: Stream terraces
Down-slope shape: Linear
Across-slope shape: Linear
Ecological site: Silty (Si) 15-19" p.z. (R044XS355MT)
510B—Meadowcreek loam, 0 to 4 percent slopes
Map Unit Setting
Elevation: 4,200 to 5,950 feet
Map Unit Description---Gallatin County Area, Montana Lakes at Valley West
Natural Resources
Conservation Service
Web Soil Survey
National Cooperative Soil Survey
6/2/2014
Page 5 of 11
Mean annual precipitation: 12 to 18 inches
Mean annual air temperature: 39 to 45 degrees F
Frost-free period: 90 to 110 days
Map Unit Composition
Meadowcreek and similar soils: 85 percent
Minor components: 15 percent
Description of Meadowcreek
Setting
Landform: Stream terraces
Down-slope shape: Linear
Across-slope shape: Linear
Parent material: Alluvium
Typical profile
A - 0 to 11 inches: slightly alkaline, loam
Bg - 11 to 25 inches: neutral, silt loam
2C - 25 to 60 inches: neutral, very gravelly sand
Properties and qualities
Slope: 0 to 4 percent
Depth to restrictive feature: More than 80 inches
Natural drainage class: Somewhat poorly drained
Capacity of the most limiting layer to transmit water (Ksat):
Moderately high to high (0.57 to 1.98 in/hr)
Depth to water table: About 24 to 42 inches
Frequency of flooding: None
Frequency of ponding: None
Salinity, maximum in profile: Nonsaline to very slightly saline (0.0 to
4.0 mmhos/cm)
Available water storage in profile: Low (about 5.1 inches)
Interpretive groups
Farmland classification: Prime farmland if irrigated
Land capability classification (irrigated): 2e
Land capability classification (nonirrigated): 3e
Hydrologic Soil Group: C
Ecological site: Subirrigated (Sb) 15-19" p.z. (R044XS359MT)
Minor Components
Blossberg
Percent of map unit: 10 percent
Landform: Terraces
Down-slope shape: Linear
Across-slope shape: Linear
Ecological site: Wet Meadow (WM) 15-19" p.z. (R044XS365MT)
Beaverton
Percent of map unit: 5 percent
Landform: Stream terraces, alluvial fans
Down-slope shape: Linear
Map Unit Description---Gallatin County Area, Montana Lakes at Valley West
Natural Resources
Conservation Service
Web Soil Survey
National Cooperative Soil Survey
6/2/2014
Page 6 of 11
Across-slope shape: Linear
Ecological site: Shallow to Gravel (SwGr) 15-19" p.z.
(R044XS354MT)
511A—Fairway silt loam, 0 to 2 percent slopes
Map Unit Setting
Elevation: 4,100 to 4,950 feet
Mean annual precipitation: 12 to 18 inches
Mean annual air temperature: 39 to 45 degrees F
Frost-free period: 90 to 110 days
Map Unit Composition
Fairway and similar soils: 85 percent
Minor components: 15 percent
Description of Fairway
Setting
Landform: Stream terraces
Down-slope shape: Linear
Across-slope shape: Linear
Parent material: Loamy alluvium
Typical profile
A - 0 to 15 inches: moderately alkaline, silt loam
Cg - 15 to 46 inches: moderately alkaline, silt loam
2Cg - 46 to 60 inches: neutral, sand
Properties and qualities
Slope: 0 to 2 percent
Depth to restrictive feature: More than 80 inches
Natural drainage class: Somewhat poorly drained
Capacity of the most limiting layer to transmit water (Ksat):
Moderately high to high (0.57 to 1.98 in/hr)
Depth to water table: About 24 to 42 inches
Frequency of flooding: None
Frequency of ponding: None
Calcium carbonate, maximum in profile: 15 percent
Salinity, maximum in profile: Nonsaline to very slightly saline (0.0 to
3.0 mmhos/cm)
Available water storage in profile: High (about 9.1 inches)
Interpretive groups
Farmland classification: Prime farmland if irrigated
Land capability classification (irrigated): 4e
Land capability classification (nonirrigated): 4e
Hydrologic Soil Group: C
Ecological site: Subirrigated (Sb) 9-14" p.z. (R044XS343MT)
Map Unit Description---Gallatin County Area, Montana Lakes at Valley West
Natural Resources
Conservation Service
Web Soil Survey
National Cooperative Soil Survey
6/2/2014
Page 7 of 11
Minor Components
Blossberg
Percent of map unit: 10 percent
Landform: Terraces
Down-slope shape: Linear
Across-slope shape: Linear
Ecological site: Wet Meadow (WM) 15-19" p.z. (R044XS365MT)
Meadowcreek
Percent of map unit: 5 percent
Landform: Stream terraces
Down-slope shape: Linear
Across-slope shape: Linear
Ecological site: Subirrigated (Sb) 15-19" p.z. (R044XS359MT)
537A—Lamoose silt loam, 0 to 2 percent slopes
Map Unit Setting
Elevation: 4,000 to 5,000 feet
Mean annual precipitation: 12 to 18 inches
Mean annual air temperature: 39 to 45 degrees F
Frost-free period: 90 to 110 days
Map Unit Composition
Lamoose and similar soils: 85 percent
Minor components: 15 percent
Description of Lamoose
Setting
Landform: Stream terraces
Down-slope shape: Linear
Across-slope shape: Linear
Parent material: Alluvium
Typical profile
A - 0 to 9 inches: moderately alkaline, silt loam
Bg - 9 to 27 inches: neutral, silt loam
2C - 27 to 60 inches: neutral, very gravelly loamy sand
Properties and qualities
Slope: 0 to 2 percent
Depth to restrictive feature: More than 80 inches
Natural drainage class: Poorly drained
Capacity of the most limiting layer to transmit water (Ksat):
Moderately high to high (0.57 to 1.98 in/hr)
Depth to water table: About 12 to 24 inches
Frequency of flooding: None
Frequency of ponding: None
Salinity, maximum in profile: Nonsaline to very slightly saline (0.0 to
3.0 mmhos/cm)
Map Unit Description---Gallatin County Area, Montana Lakes at Valley West
Natural Resources
Conservation Service
Web Soil Survey
National Cooperative Soil Survey
6/2/2014
Page 8 of 11
Available water storage in profile: Low (about 5.8 inches)
Interpretive groups
Farmland classification: Farmland of local importance
Land capability classification (irrigated): None specified
Land capability classification (nonirrigated): 5w
Hydrologic Soil Group: B/D
Ecological site: Wet Meadow (WM) 9-14" p.z. (R044XS349MT)
Minor Components
Bonebasin
Percent of map unit: 10 percent
Landform: Terraces
Down-slope shape: Linear
Across-slope shape: Linear
Ecological site: Wet Meadow (WM) 15-19" p.z. (R044XS365MT)
Meadowcreek
Percent of map unit: 5 percent
Landform: Stream terraces
Down-slope shape: Linear
Across-slope shape: Linear
Ecological site: Subirrigated (Sb) 9-14" p.z. (R044XS343MT)
748A—Hyalite-Beaverton complex, 0 to 4 percent slopes
Map Unit Setting
Elevation: 4,350 to 6,150 feet
Mean annual precipitation: 15 to 19 inches
Mean annual air temperature: 39 to 45 degrees F
Frost-free period: 90 to 110 days
Map Unit Composition
Hyalite and similar soils: 70 percent
Beaverton and similar soils: 20 percent
Minor components: 10 percent
Description of Hyalite
Setting
Landform: Stream terraces, alluvial fans
Down-slope shape: Linear
Across-slope shape: Linear
Parent material: Loamy alluvium
Typical profile
A - 0 to 5 inches: neutral, loam
Bt1 - 5 to 9 inches: neutral, clay loam
Bt2 - 9 to 17 inches: neutral, silty clay loam
2Bt3 - 17 to 26 inches: neutral, very cobbly sandy clay loam
3C - 26 to 60 inches: neutral, very cobbly loamy sand
Map Unit Description---Gallatin County Area, Montana Lakes at Valley West
Natural Resources
Conservation Service
Web Soil Survey
National Cooperative Soil Survey
6/2/2014
Page 9 of 11
Properties and qualities
Slope: 0 to 4 percent
Depth to restrictive feature: More than 80 inches
Natural drainage class: Well drained
Capacity of the most limiting layer to transmit water (Ksat):
Moderately high (0.20 to 0.57 in/hr)
Depth to water table: More than 80 inches
Frequency of flooding: None
Frequency of ponding: None
Calcium carbonate, maximum in profile: 5 percent
Available water storage in profile: Low (about 4.4 inches)
Interpretive groups
Farmland classification: Farmland of local importance
Land capability classification (irrigated): 3e
Land capability classification (nonirrigated): 4e
Hydrologic Soil Group: C
Ecological site: Shallow to Gravel (SwGr) 15-19" p.z.
(R044XS354MT)
Description of Beaverton
Setting
Landform: Stream terraces, alluvial fans
Down-slope shape: Linear
Across-slope shape: Linear
Parent material: Alluvium
Typical profile
A - 0 to 5 inches: neutral, cobbly loam
Bt - 5 to 21 inches: neutral, very gravelly clay loam
Bk - 21 to 25 inches: moderately alkaline, very cobbly coarse sandy
loam
2Bk - 25 to 60 inches: moderately alkaline, extremely cobbly loamy
coarse sand
Properties and qualities
Slope: 0 to 4 percent
Depth to restrictive feature: More than 80 inches
Natural drainage class: Well drained
Capacity of the most limiting layer to transmit water (Ksat):
Moderately high to high (0.57 to 1.98 in/hr)
Depth to water table: More than 80 inches
Frequency of flooding: None
Frequency of ponding: None
Calcium carbonate, maximum in profile: 15 percent
Salinity, maximum in profile: Nonsaline (0.0 to 2.0 mmhos/cm)
Available water storage in profile: Low (about 3.7 inches)
Interpretive groups
Farmland classification: Farmland of local importance
Land capability classification (irrigated): 4s
Land capability classification (nonirrigated): 6s
Map Unit Description---Gallatin County Area, Montana Lakes at Valley West
Natural Resources
Conservation Service
Web Soil Survey
National Cooperative Soil Survey
6/2/2014
Page 10 of 11
Hydrologic Soil Group: B
Ecological site: Shallow to Gravel (SwGr) 15-19" p.z.
(R044XS354MT)
Minor Components
Turner
Percent of map unit: 5 percent
Landform: Stream terraces
Down-slope shape: Linear
Across-slope shape: Linear
Ecological site: Silty (Si) 15-19" p.z. (R044XS355MT)
Hyalite
Percent of map unit: 5 percent
Landform: Stream terraces, alluvial fans
Down-slope shape: Linear
Across-slope shape: Linear
Ecological site: Shallow to Gravel (SwGr) 15-19" p.z.
(R044XS354MT)
Data Source Information
Soil Survey Area: Gallatin County Area, Montana
Survey Area Data: Version 17, Dec 10, 2013
Map Unit Description---Gallatin County Area, Montana Lakes at Valley West
Natural Resources
Conservation Service
Web Soil Survey
National Cooperative Soil Survey
6/2/2014
Page 11 of 11
Engineering Properties–Gallatin County Area, Montana
Map unit symbol and
soil name
Pct. of
map
unit
Hydrolo
gic
group
Depth USDA texture Classification Fragments Percentage passing sieve number—Liquid
limit
Plasticit
y indexUnifiedAASHTO>10
inches
3-10
inches
4 10 40 200
In Pct Pct Pct
448A—Hyalite-
Beaverton complex,
moderately wet, 0 to
2 percent slopes
Hyalite 70 C 0-5 Loam CL-ML A-4 0 0-10 95-100 90-100 75-95 55-75 25-30 5-10
5-9 Clay loam, loam, silty
clay loam
CL A-6 0 0-10 90-100 85-100 75-90 60-80 30-35 10-15
9-17 Clay loam, silty clay
loam, gravelly
loam
CL, GC,
SC
A-6 0 0-15 65-95 60-90 55-80 40-75 30-35 10-15
17-26 Very cobbly sandy
clay loam, very
cobbly sandy
loam, extremely
cobbly sandy loam
GM, SM A-1, A-2 0 30-55 35-65 30-60 20-50 10-25 20-35 NP-10
Engineering Properties---Gallatin County Area, Montana Lakes at Valley West
Natural Resources
Conservation Service
Web Soil Survey
National Cooperative Soil Survey
6/3/2014
Page 4 of 8
Engineering Properties–Gallatin County Area, Montana
Map unit symbol and
soil name
Pct. of
map
unit
Hydrolo
gic
group
Depth USDA texture Classification Fragments Percentage passing sieve number—Liquid
limit
Plasticit
y indexUnifiedAASHTO>10
inches
3-10
inches
4 10 40 200
In Pct Pct Pct
26-60 Very cobbly loamy
sand, very cobbly
sand, extremely
cobbly coarse
sand
GM, GP-
GM,
SM, SP-
SM
A-1 0 30-55 35-65 30-60 15-40 5-15 —NP
Beaverton 20 B 0-5 Cobbly loam CL-ML,
SC-SM
A-4 0 15-30 75-95 70-90 60-80 45-65 25-30 5-10
5-21 Very cobbly clay
loam, very cobbly
sandy clay loam,
very gravelly clay
loam
GC, GC-
GM,
SC, SC-
SM
A-2, A-4,
A-6
0 20-40 45-70 40-60 35-55 20-40 25-35 5-15
21-25 Very cobbly coarse
sandy loam
GM, GP-
GM,
SM, SP-
SM
A-1 0 25-50 30-75 20-65 10-50 5-15 —NP
25-60 Extremely cobbly
loamy coarse
sand, extremely
gravelly sand, very
cobbly loamy sand
GM, GP-
GM,
SM, SP-
SM
A-1 0 25-50 30-75 20-65 10-50 5-15 —NP
509B—Enbar loam, 0
to 4 percent slopes
Enbar 85 C 0-22 Loam CL-ML A-4 0 0 80-100 75-100 60-85 50-75 20-30 5-10
22-49 Loam, sandy loam CL-ML,
ML
A-4 0 0 80-100 75-100 60-85 50-75 20-30 NP-10
49-60 Very gravelly sandy
loam, very gravelly
loamy sand,
extremely gravelly
sandy loam
GM, GP-
GM
A-1, A-2 0 0-10 25-60 15-50 10-40 5-30 15-25 NP-5
Engineering Properties---Gallatin County Area, Montana Lakes at Valley West
Natural Resources
Conservation Service
Web Soil Survey
National Cooperative Soil Survey
6/3/2014
Page 5 of 8
Engineering Properties–Gallatin County Area, Montana
Map unit symbol and
soil name
Pct. of
map
unit
Hydrolo
gic
group
Depth USDA texture Classification Fragments Percentage passing sieve number—Liquid
limit
Plasticit
y indexUnifiedAASHTO>10
inches
3-10
inches
4 10 40 200
In Pct Pct Pct
510B—Meadowcreek
loam, 0 to 4 percent
slopes
Meadowcreek 85 C 0-11 Loam CL-ML A-4 0 0 95-100 90-100 70-95 50-75 20-30 5-10
11-25 Loam, sandy loam,
silt loam
CL-ML,
SC-SM
A-4 0 0 95-100 90-100 70-90 40-75 20-30 5-10
25-60 Very gravelly sand,
extremely gravelly
sand, very gravelly
loamy sand
GP, GP-
GM
A-1 0 0-10 25-45 15-35 10-25 0-10 0-19 NP
511A—Fairway silt
loam, 0 to 2 percent
slopes
Fairway 85 C 0-15 Silt loam CL-ML A-4 0 0 100 100 90-100 70-90 20-30 5-10
15-46 Silt loam, loam, silty
clay loam
CL, CL-
ML
A-4, A-6 0 0 100 100 85-100 60-90 25-40 5-15
46-60 Sand, gravelly loamy
sand, very gravelly
sand
GP-GM,
SM, SP,
SP-SM
A-1, A-2 0 0-10 40-100 30-100 20-60 0-15 —NP
537A—Lamoose silt
loam, 0 to 2 percent
slopes
Lamoose 85 B/D 0-9 Silt loam CL, CL-
ML
A-4, A-6 0 0 80-100 75-100 70-95 55-90 25-35 5-15
9-27 Loam, silt loam,
gravelly loam
CL, CL-
ML, GC,
GC-GM
A-2, A-4,
A-6
0 0 55-100 50-100 45-95 30-85 25-35 5-15
27-60 Very gravelly loamy
sand, very gravelly
sand, extremely
gravelly sand
GM, GP,
GP-GM
A-1 0 0-20 25-55 20-50 10-40 0-15 0-14 NP
Engineering Properties---Gallatin County Area, Montana Lakes at Valley West
Natural Resources
Conservation Service
Web Soil Survey
National Cooperative Soil Survey
6/3/2014
Page 6 of 8
Engineering Properties–Gallatin County Area, Montana
Map unit symbol and
soil name
Pct. of
map
unit
Hydrolo
gic
group
Depth USDA texture Classification Fragments Percentage passing sieve number—Liquid
limit
Plasticit
y indexUnifiedAASHTO>10
inches
3-10
inches
4 10 40 200
In Pct Pct Pct
748A—Hyalite-
Beaverton complex,
0 to 4 percent slopes
Hyalite 70 C 0-5 Loam CL-ML A-4 0 0-10 95-100 90-100 75-95 55-75 25-30 5-10
5-9 Clay loam, loam, silty
clay loam
CL A-6 0 0-10 90-100 85-100 75-90 60-80 30-35 10-15
9-17 Clay loam, silty clay
loam, gravelly
loam
CL, GC,
SC
A-6 0 0-15 65-95 60-90 55-80 40-75 30-35 10-15
17-26 Very cobbly sandy
clay loam, very
cobbly sandy
loam, extremely
cobbly sandy loam
GM, SM A-2, A-1 0 30-55 35-65 30-60 20-50 10-25 20-35 NP-10
Engineering Properties---Gallatin County Area, Montana Lakes at Valley West
Natural Resources
Conservation Service
Web Soil Survey
National Cooperative Soil Survey
6/3/2014
Page 7 of 8
Engineering Properties–Gallatin County Area, Montana
Map unit symbol and
soil name
Pct. of
map
unit
Hydrolo
gic
group
Depth USDA texture Classification Fragments Percentage passing sieve number—Liquid
limit
Plasticit
y indexUnifiedAASHTO>10
inches
3-10
inches
4 10 40 200
In Pct Pct Pct
26-60 Very cobbly loamy
sand, very cobbly
sand, extremely
cobbly coarse
sand
GM, GP-
GM,
SM, SP-
SM
A-1 0 30-55 35-65 30-60 15-40 5-15 —NP
Beaverton 20 B 0-5 Cobbly loam CL-ML,
SC-SM
A-4 0 15-30 75-95 70-90 60-80 45-65 25-30 5-10
5-21 Very cobbly clay
loam, very cobbly
sandy clay loam,
very gravelly clay
loam
GC, GC-
GM,
SC, SC-
SM
A-2, A-4,
A-6
0 20-40 45-70 40-60 35-55 20-40 25-35 5-15
21-25 Very cobbly coarse
sandy loam
GM, GP-
GM,
SM, SP-
SM
A-1 0 25-50 30-75 20-65 10-50 5-15 —NP
25-60 Extremely cobbly
loamy coarse
sand, extremely
gravelly sand, very
cobbly loamy sand
GM, GP-
GM,
SM, SP-
SM
A-1 0 25-50 30-75 20-65 10-50 5-15 —NP
Data Source Information
Soil Survey Area: Gallatin County Area, Montana
Survey Area Data: Version 17, Dec 10, 2013
Engineering Properties---Gallatin County Area, Montana Lakes at Valley West
Natural Resources
Conservation Service
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6/3/2014
Page 8 of 8
Report—Physical Soil Properties
Physical Soil Properties–Gallatin County Area, Montana
Map symbol
and soil name
Depth Sand Silt Clay Moist
bulk
density
Saturated
hydraulic
conductivity
Available
water
capacity
Linear
extensibility
Organic
matter
Erosion
factors
Wind
erodibility
group
Wind
erodibility
indexKwKfT
In Pct Pct Pct g/cc micro m/sec In/In Pct Pct
448A—Hyalite-
Beaverton
complex,
moderately
wet, 0 to 2
percent
slopes
Hyalite 0-5 -40--38-18-23- 27 1.10-1.20 4.00-14.00 0.18-0.19 0.0-2.9 2.0-4.0 .32 .32 3 6 48
5-9 -34--37-25-30- 35 1.30-1.40 1.40-4.00 0.16-0.19 3.0-5.9 1.0-3.0 .32 .32
9-17 -17--53-25-30- 35 1.30-1.40 1.40-4.00 0.12-0.17 3.0-5.9 1.0-3.0 .37 .37
17-26 -61--19-15-20- 25 1.50-1.60 1.40-4.00 0.03-0.08 0.0-2.9 0.5-1.0 .10 .28
26-60 -79--17-0- 5- 10 1.60-1.70 42.00-141.00 0.02-0.04 0.0-2.9 0.0-0.5 .05 .24
Beaverton 0-5 -39--37-20-24- 27 1.20-1.40 4.00-14.00 0.14-0.16 0.0-2.9 1.0-3.0 .15 .24 3 7 38
5-21 -34--37-25-30- 35 1.40-1.60 4.00-14.00 0.08-0.10 0.0-2.9 0.5-1.0 .10 .32
21-25 -67--19-10-14- 18 1.55-1.75 42.00-141.00 0.03-0.04 0.0-2.9 0.0-0.5 .05 .17
25-60 -84--11-0- 5- 10 1.55-1.75 42.00-141.00 0.03-0.04 0.0-2.9 0.0-0.5 .02 .05
509B—Enbar
loam, 0 to 4
percent
slopes
Enbar 0-22 -40--38-18-23- 27 1.15-1.35 4.00-14.00 0.16-0.20 0.0-2.9 3.0-5.0 .28 .28 4 6 48
22-49 -66--15-18-19- 27 1.35-1.55 4.00-14.00 0.14-0.18 0.0-2.9 0.5-1.0 .20 .20
49-60 -84-- 4-5-12- 18 1.50-1.70 14.00-42.00 0.04-0.05 0.0-2.9 0.0 .02 .02
Physical Soil Properties---Gallatin County Area, Montana Lakes at Valley West
Natural Resources
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6/3/2014
Page 4 of 6
Physical Soil Properties–Gallatin County Area, Montana
Map symbol
and soil name
Depth Sand Silt Clay Moist
bulk
density
Saturated
hydraulic
conductivity
Available
water
capacity
Linear
extensibility
Organic
matter
Erosion
factors
Wind
erodibility
group
Wind
erodibility
indexKwKfT
In Pct Pct Pct g/cc micro m/sec In/In Pct Pct
510B—
Meadowcree
k loam, 0 to 4
percent
slopes
Meadowcreek 0-11 -41--37-18-22- 25 1.20-1.40 4.00-14.00 0.18-0.20 0.0-2.9 2.0-5.0 .24 .24 3 6 48
11-25 -20--54-18-26- 27 1.20-1.40 4.00-14.00 0.13-0.15 0.0-2.9 1.0-3.0 .37 .37
25-60 -96-- 2-0- 3- 5 1.20-1.50 141.00 0.02-0.03 0.0-2.9 0.0-0.5 .02 .02
511A—Fairway
silt loam, 0 to
2 percent
slopes
Fairway 0-15 -26--53-15-21- 27 1.20-1.40 4.00-14.00 0.18-0.22 0.0-2.9 2.0-5.0 .24 .24 4 4L 86
15-46 -21--55-18-24- 30 1.20-1.40 4.00-14.00 0.16-0.20 0.0-2.9 1.0-2.0 .43 .43
46-60 -94-- 1-0- 5- 10 1.20-1.50 42.00-141.00 0.03-0.04 0.0-2.9 0.5-1.0 .02 .02
537A—
Lamoose silt
loam, 0 to 2
percent
slopes
Lamoose 0-9 -22--55-18-23- 27 1.10-1.20 4.00-14.00 0.17-0.21 0.0-2.9 4.0-6.0 .28 .28 3 6 48
9-27 -22--55-18-23- 27 1.15-1.30 4.00-14.00 0.15-0.18 0.0-2.9 2.0-4.0 .20 .37
27-60 -79--17-0- 5- 10 1.60-1.75 42.00-141.00 0.02-0.03 0.0-2.9 0.0-0.5 .05 .15
Physical Soil Properties---Gallatin County Area, Montana Lakes at Valley West
Natural Resources
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Page 5 of 6
Physical Soil Properties–Gallatin County Area, Montana
Map symbol
and soil name
Depth Sand Silt Clay Moist
bulk
density
Saturated
hydraulic
conductivity
Available
water
capacity
Linear
extensibility
Organic
matter
Erosion
factors
Wind
erodibility
group
Wind
erodibility
indexKwKfT
In Pct Pct Pct g/cc micro m/sec In/In Pct Pct
748A—Hyalite-
Beaverton
complex, 0 to
4 percent
slopes
Hyalite 0-5 -40--38-18-23- 27 1.10-1.20 4.00-14.00 0.18-0.19 0.0-2.9 2.0-4.0 .32 .32 3 6 48
5-9 -34--37-25-30- 35 1.30-1.40 1.40-4.00 0.16-0.19 3.0-5.9 1.0-3.0 .32 .32
9-17 -17--53-25-30- 35 1.30-1.40 1.40-4.00 0.12-0.17 3.0-5.9 1.0-3.0 .37 .37
17-26 -61--19-15-20- 25 1.50-1.60 1.40-4.00 0.03-0.08 0.0-2.9 0.5-1.0 .10 .28
26-60 -79--17-0- 5- 10 1.60-1.70 42.00-141.00 0.02-0.04 0.0-2.9 0.0-0.5 .05 .24
Beaverton 0-5 -39--37-20-24- 27 1.20-1.40 4.00-14.00 0.14-0.16 0.0-2.9 1.0-3.0 .15 .24 3 7 38
5-21 -34--37-25-30- 35 1.40-1.60 4.00-14.00 0.08-0.10 0.0-2.9 0.5-1.0 .10 .32
21-25 -67--19-10-14- 18 1.55-1.75 42.00-141.00 0.03-0.04 0.0-2.9 0.0-0.5 .05 .17
25-60 -84--11-0- 5- 10 1.55-1.75 42.00-141.00 0.03-0.04 0.0-2.9 0.0-0.5 .02 .05
Data Source Information
Soil Survey Area: Gallatin County Area, Montana
Survey Area Data: Version 17, Dec 10, 2013
Physical Soil Properties---Gallatin County Area, Montana Lakes at Valley West
Natural Resources
Conservation Service
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6/3/2014
Page 6 of 6
Corrosion of Concrete—Gallatin County Area, Montana
(Lakes at Valley West)
Natural Resources
Conservation Service
Web Soil Survey
National Cooperative Soil Survey
6/2/2014
Page 1 of 350586605058750505884050589305059020505911050592005058660505875050588405058930505902050591105059200490600490690490780490870490960491050491140491230491320491410491500
490600 490690 490780 490870 490960 491050 491140 491230 491320 491410
45° 41' 11'' N 111° 7' 14'' W45° 41' 11'' N111° 6' 32'' W45° 40' 52'' N
111° 7' 14'' W45° 40' 52'' N
111° 6' 32'' WN
Map projection: Web Mercator Corner coordinates: WGS84 Edge tics: UTM Zone 12N WGS84
0 200 400 800 1200Feet
0 50 100 200 300Meters
Map Scale: 1:4,120 if printed on A landscape (11" x 8.5") sheet.
Corrosion of Concrete
Corrosion of Concrete— Summary by Map Unit — Gallatin County Area, Montana (MT622)
Map unit symbol Map unit name Rating Acres in AOI Percent of AOI
448A Hyalite-Beaverton
complex, moderately
wet, 0 to 2 percent
slopes
Low 1.1 1.3%
509B Enbar loam, 0 to 4
percent slopes
Low 6.0 7.3%
510B Meadowcreek loam, 0 to
4 percent slopes
Moderate 20.2 24.8%
511A Fairway silt loam, 0 to 2
percent slopes
Low 1.0 1.2%
537A Lamoose silt loam, 0 to 2
percent slopes
Low 16.1 19.7%
748A Hyalite-Beaverton
complex, 0 to 4
percent slopes
Low 37.3 45.7%
Totals for Area of Interest 81.6 100.0%
Description
"Risk of corrosion" pertains to potential soil-induced electrochemical or chemical
action that corrodes or weakens concrete. The rate of corrosion of concrete is based
mainly on the sulfate and sodium content, texture, moisture content, and acidity of
the soil. Special site examination and design may be needed if the combination of
factors results in a severe hazard of corrosion. The concrete in installations that
intersect soil boundaries or soil layers is more susceptible to corrosion than the
concrete in installations that are entirely within one kind of soil or within one soil
layer.
The risk of corrosion is expressed as "low," "moderate," or "high."
Rating Options
Aggregation Method: Dominant Condition
Component Percent Cutoff: None Specified
Tie-break Rule: Higher
Corrosion of Concrete—Gallatin County Area, Montana Lakes at Valley West
Natural Resources
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6/2/2014
Page 3 of 3
Corrosion of Steel—Gallatin County Area, Montana
(Lakes at Valley West)
Natural Resources
Conservation Service
Web Soil Survey
National Cooperative Soil Survey
6/2/2014
Page 1 of 350586605058750505884050589305059020505911050592005058660505875050588405058930505902050591105059200490600490690490780490870490960491050491140491230491320491410491500
490600 490690 490780 490870 490960 491050 491140 491230 491320 491410
45° 41' 11'' N 111° 7' 14'' W45° 41' 11'' N111° 6' 32'' W45° 40' 52'' N
111° 7' 14'' W45° 40' 52'' N
111° 6' 32'' WN
Map projection: Web Mercator Corner coordinates: WGS84 Edge tics: UTM Zone 12N WGS84
0 200 400 800 1200Feet
0 50 100 200 300Meters
Map Scale: 1:4,120 if printed on A landscape (11" x 8.5") sheet.
Corrosion of Steel
Corrosion of Steel— Summary by Map Unit — Gallatin County Area, Montana (MT622)
Map unit symbol Map unit name Rating Acres in AOI Percent of AOI
448A Hyalite-Beaverton
complex, moderately
wet, 0 to 2 percent
slopes
Moderate 1.1 1.3%
509B Enbar loam, 0 to 4
percent slopes
Moderate 6.0 7.3%
510B Meadowcreek loam, 0 to
4 percent slopes
High 20.2 24.8%
511A Fairway silt loam, 0 to 2
percent slopes
High 1.0 1.2%
537A Lamoose silt loam, 0 to 2
percent slopes
High 16.1 19.7%
748A Hyalite-Beaverton
complex, 0 to 4
percent slopes
Low 37.3 45.7%
Totals for Area of Interest 81.6 100.0%
Description
"Risk of corrosion" pertains to potential soil-induced electrochemical or chemical
action that corrodes or weakens uncoated steel. The rate of corrosion of uncoated
steel is related to such factors as soil moisture, particle-size distribution, acidity,
and electrical conductivity of the soil. Special site examination and design may be
needed if the combination of factors results in a severe hazard of corrosion. The
steel in installations that intersect soil boundaries or soil layers is more susceptible
to corrosion than the steel in installations that are entirely within one kind of soil or
within one soil layer.
The risk of corrosion is expressed as "low," "moderate," or "high."
Rating Options
Aggregation Method: Dominant Condition
Component Percent Cutoff: None Specified
Tie-break Rule: Higher
Corrosion of Steel—Gallatin County Area, Montana Lakes at Valley West
Natural Resources
Conservation Service
Web Soil Survey
National Cooperative Soil Survey
6/2/2014
Page 3 of 3
Dwellings With Basements—Gallatin County Area, Montana
(Lakes at Valley West)
Natural Resources
Conservation Service
Web Soil Survey
National Cooperative Soil Survey
6/2/2014
Page 1 of 650586605058750505884050589305059020505911050592005058660505875050588405058930505902050591105059200490600490690490780490870490960491050491140491230491320491410491500
490600 490690 490780 490870 490960 491050 491140 491230 491320 491410
45° 41' 11'' N 111° 7' 14'' W45° 41' 11'' N111° 6' 32'' W45° 40' 52'' N
111° 7' 14'' W45° 40' 52'' N
111° 6' 32'' WN
Map projection: Web Mercator Corner coordinates: WGS84 Edge tics: UTM Zone 12N WGS84
0 200 400 800 1200Feet
0 50 100 200 300Meters
Map Scale: 1:4,120 if printed on A landscape (11" x 8.5") sheet.
Dwellings With Basements
Dwellings With Basements— Summary by Map Unit — Gallatin County Area, Montana (MT622)
Map unit
symbol
Map unit name Rating Component
name (percent)
Rating reasons
(numeric
values)
Acres in AOI Percent of AOI
448A Hyalite-
Beaverton
complex,
moderately
wet, 0 to 2
percent slopes
Somewhat
limited
Hyalite (70%)Large stones
(0.02)
1.1 1.3%
Beaverton (20%)Large stones
(0.20)
Beaverton (5%)Large stones
(0.21)
Meadowcreek
(5%)
Depth to
saturated zone
(0.99)
509B Enbar loam, 0 to
4 percent
slopes
Very limited Enbar (85%)Flooding (1.00)6.0 7.3%
Depth to
saturated zone
(0.99)
Nythar (10%)Flooding (1.00)
Depth to
saturated zone
(1.00)
Shrink-swell
(0.50)
510B Meadowcreek
loam, 0 to 4
percent slopes
Somewhat
limited
Meadowcreek
(85%)
Depth to
saturated zone
(0.99)
20.2 24.8%
Beaverton (5%)Large stones
(0.64)
511A Fairway silt loam,
0 to 2 percent
slopes
Somewhat
limited
Fairway (85%)Depth to
saturated zone
(0.99)
1.0 1.2%
Meadowcreek
(5%)
Depth to
saturated zone
(0.99)
537A Lamoose silt
loam, 0 to 2
percent slopes
Very limited Lamoose (85%)Depth to
saturated zone
(1.00)
16.1 19.7%
Bonebasin (10%)Flooding (1.00)
Depth to
saturated zone
(1.00)
Meadowcreek
(5%)
Flooding (1.00)
Depth to
saturated zone
(0.99)
Dwellings With Basements—Gallatin County Area, Montana Lakes at Valley West
Natural Resources
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6/2/2014
Page 3 of 6
Dwellings With Basements— Summary by Map Unit — Gallatin County Area, Montana (MT622)
Map unit
symbol
Map unit name Rating Component
name (percent)
Rating reasons
(numeric
values)
Acres in AOI Percent of AOI
748A Hyalite-
Beaverton
complex, 0 to 4
percent slopes
Somewhat
limited
Hyalite (70%)Large stones
(0.02)
37.3 45.7%
Beaverton (20%)Large stones
(0.20)
Hyalite (5%)Large stones
(0.02)
Totals for Area of Interest 81.6 100.0%
Dwellings With Basements— Summary by Rating Value
Rating Acres in AOI Percent of AOI
Somewhat limited 59.6 73.0%
Very limited 22.0 27.0%
Totals for Area of Interest 81.6 100.0%
Dwellings With Basements—Gallatin County Area, Montana Lakes at Valley West
Natural Resources
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6/2/2014
Page 4 of 6
Dwellings Without Basements—Gallatin County Area, Montana
(Lakes at Valley West)
Natural Resources
Conservation Service
Web Soil Survey
National Cooperative Soil Survey
6/2/2014
Page 1 of 550586605058750505884050589305059020505911050592005058660505875050588405058930505902050591105059200490600490690490780490870490960491050491140491230491320491410491500
490600 490690 490780 490870 490960 491050 491140 491230 491320 491410
45° 41' 11'' N 111° 7' 14'' W45° 41' 11'' N111° 6' 32'' W45° 40' 52'' N
111° 7' 14'' W45° 40' 52'' N
111° 6' 32'' WN
Map projection: Web Mercator Corner coordinates: WGS84 Edge tics: UTM Zone 12N WGS84
0 200 400 800 1200Feet
0 50 100 200 300Meters
Map Scale: 1:4,120 if printed on A landscape (11" x 8.5") sheet.
Dwellings Without Basements
Dwellings Without Basements— Summary by Map Unit — Gallatin County Area, Montana (MT622)
Map unit
symbol
Map unit name Rating Component
name (percent)
Rating reasons
(numeric
values)
Acres in AOI Percent of AOI
448A Hyalite-
Beaverton
complex,
moderately
wet, 0 to 2
percent slopes
Somewhat
limited
Hyalite (70%)Large stones
(0.02)
1.1 1.3%
Beaverton (20%)Large stones
(0.20)
Beaverton (5%)Large stones
(0.21)
509B Enbar loam, 0 to
4 percent
slopes
Very limited Enbar (85%)Flooding (1.00)6.0 7.3%
Nythar (10%)Flooding (1.00)
Depth to
saturated zone
(1.00)
Shrink-swell
(0.50)
510B Meadowcreek
loam, 0 to 4
percent slopes
Not limited Meadowcreek
(85%)
20.2 24.8%
511A Fairway silt loam,
0 to 2 percent
slopes
Not limited Fairway (85%)1.0 1.2%
Meadowcreek
(5%)
537A Lamoose silt
loam, 0 to 2
percent slopes
Somewhat
limited
Lamoose (85%)Depth to
saturated zone
(0.98)
16.1 19.7%
748A Hyalite-
Beaverton
complex, 0 to 4
percent slopes
Somewhat
limited
Hyalite (70%)Large stones
(0.02)
37.3 45.7%
Beaverton (20%)Large stones
(0.20)
Turner (5%)Shrink-swell
(0.00)
Hyalite (5%)Large stones
(0.02)
Totals for Area of Interest 81.6 100.0%
Dwellings Without Basements— Summary by Rating Value
Rating Acres in AOI Percent of AOI
Somewhat limited 54.4 66.7%
Not limited 21.2 26.0%
Very limited 6.0 7.3%
Totals for Area of Interest 81.6 100.0%
Dwellings Without Basements—Gallatin County Area, Montana Lakes at Valley West
Natural Resources
Conservation Service
Web Soil Survey
National Cooperative Soil Survey
6/2/2014
Page 3 of 5
Water Features–Gallatin County Area, Montana
Map unit symbol and soil
name
Hydrologic
group
Surface
runoff
Month Water table Ponding Flooding
Upper limit Lower limit Surface
depth
Duration Frequency Duration Frequency
Ft Ft Ft
448A—Hyalite-Beaverton
complex, moderately wet,
0 to 2 percent slopes
Hyalite C —January ————None —None
February ————None —None
March ————None —None
April ————None —None
May 4.0-8.0 >6.0 ——None —None
June 4.0-8.0 >6.0 ——None —None
July 4.0-8.0 >6.0 ——None —None
August 4.0-8.0 >6.0 ——None —None
September ————None —None
October ————None —None
November ————None —None
Water Features---Gallatin County Area, Montana 014095CR
Natural Resources
Conservation Service
Web Soil Survey
National Cooperative Soil Survey
10/9/2014
Page 4 of 10
Water Features–Gallatin County Area, Montana
Map unit symbol and soil
name
Hydrologic
group
Surface
runoff
Month Water table Ponding Flooding
Upper limit Lower limit Surface
depth
Duration Frequency Duration Frequency
Ft Ft Ft
December ————None —None
Beaverton B —January ————None —None
February ————None —None
March ————None —None
April ————None —None
May 4.0-8.0 >6.0 ——None —None
June 4.0-8.0 >6.0 ——None —None
July 4.0-8.0 >6.0 ——None —None
August 4.0-8.0 >6.0 ——None —None
September ————None —None
October ————None —None
November ————None —None
December ————None —None
509B—Enbar loam, 0 to 4
percent slopes
Enbar C —January ————None Brief Rare
February ————None Brief Rare
March ————None Brief Rare
April 2.0-3.5 >6.0 ——None Brief Rare
May 2.0-3.5 >6.0 ——None Brief Rare
June 2.0-3.5 >6.0 ——None Brief Rare
July 2.0-3.5 >6.0 ——None Brief Rare
Water Features---Gallatin County Area, Montana 014095CR
Natural Resources
Conservation Service
Web Soil Survey
National Cooperative Soil Survey
10/9/2014
Page 5 of 10
Water Features–Gallatin County Area, Montana
Map unit symbol and soil
name
Hydrologic
group
Surface
runoff
Month Water table Ponding Flooding
Upper limit Lower limit Surface
depth
Duration Frequency Duration Frequency
Ft Ft Ft
510B—Meadowcreek loam,
0 to 4 percent slopes
Meadowcreek C —January ————None —None
February ————None —None
March ————None —None
April 2.0-3.5 >6.0 ——None —None
May 2.0-3.5 >6.0 ——None —None
June 2.0-3.5 >6.0 ——None —None
July ————None —None
August ————None —None
September ————None —None
October ————None —None
November ————None —None
December ————None —None
Water Features---Gallatin County Area, Montana 014095CR
Natural Resources
Conservation Service
Web Soil Survey
National Cooperative Soil Survey
10/9/2014
Page 6 of 10
Water Features–Gallatin County Area, Montana
Map unit symbol and soil
name
Hydrologic
group
Surface
runoff
Month Water table Ponding Flooding
Upper limit Lower limit Surface
depth
Duration Frequency Duration Frequency
Ft Ft Ft
511A—Fairway silt loam, 0 to
2 percent slopes
Fairway C —January ————None —None
February ————None —None
March ————None —None
April 2.0-3.5 >6.0 ——None —None
May 2.0-3.5 >6.0 ——None —None
June 2.0-3.5 >6.0 ——None —None
July ————None —None
August ————None —None
September ————None —None
October ————None —None
November ————None —None
December ————None —None
Water Features---Gallatin County Area, Montana 014095CR
Natural Resources
Conservation Service
Web Soil Survey
National Cooperative Soil Survey
10/9/2014
Page 7 of 10
Water Features–Gallatin County Area, Montana
Map unit symbol and soil
name
Hydrologic
group
Surface
runoff
Month Water table Ponding Flooding
Upper limit Lower limit Surface
depth
Duration Frequency Duration Frequency
Ft Ft Ft
537A—Lamoose silt loam, 0
to 2 percent slopes
Lamoose B/D —January ————None —None
February ————None —None
March ————None —None
April 1.0-2.0 >6.0 ——None —None
May 1.0-2.0 >6.0 ——None —None
June 1.0-2.0 >6.0 ——None —None
July 1.0-2.0 >6.0 ——None —None
August ————None —None
September ————None —None
October ————None —None
November ————None —None
December ————None —None
Water Features---Gallatin County Area, Montana 014095CR
Natural Resources
Conservation Service
Web Soil Survey
National Cooperative Soil Survey
10/9/2014
Page 8 of 10
Water Features–Gallatin County Area, Montana
Map unit symbol and soil
name
Hydrologic
group
Surface
runoff
Month Water table Ponding Flooding
Upper limit Lower limit Surface
depth
Duration Frequency Duration Frequency
Ft Ft Ft
748A—Hyalite-Beaverton
complex, 0 to 4 percent
slopes
Hyalite C —January ————None —None
February ————None —None
March ————None —None
April ————None —None
May ————None —None
June ————None —None
July ————None —None
August ————None —None
September ————None —None
October ————None —None
November ————None —None
Water Features---Gallatin County Area, Montana 014095CR
Natural Resources
Conservation Service
Web Soil Survey
National Cooperative Soil Survey
10/9/2014
Page 9 of 10
Water Features–Gallatin County Area, Montana
Map unit symbol and soil
name
Hydrologic
group
Surface
runoff
Month Water table Ponding Flooding
Upper limit Lower limit Surface
depth
Duration Frequency Duration Frequency
Ft Ft Ft
December ————None —None
Beaverton B —January ————None —None
February ————None —None
March ————None —None
April ————None —None
May ————None —None
June ————None —None
July ————None —None
August ————None —None
September ————None —None
October ————None —None
November ————None —None
December ————None —None
Data Source Information
Soil Survey Area: Gallatin County Area, Montana
Survey Area Data: Version 17, Dec 10, 2013
Water Features---Gallatin County Area, Montana 014095CR
Natural Resources
Conservation Service
Web Soil Survey
National Cooperative Soil Survey
10/9/2014
Page 10 of 10
Project:Lakes at Valley West
Project Location:Bozeman, MT
Project Number:014095CR
Log of Boring TH-1
Date(s)
Drilled 9-9-2014
Drilling
Method Excavator
Drill Rig
Type Cat 325BL
Groundwater Level
and Date Measured 9'8"
Borehole
Backfill spoils
Logged By DB
Drill Bit
Size/Type
Drilling
Contractor SIME
Sampling
Method(s)
Location Northeast portion of property (east of Laurel Pkwy)
Checked By AP
Total Depth
of Borehole 9'8"
Approximate
Surface Elevation
Hammer
Data
Material TypeOL-ML
GP
CL
GP
REMARKS AND OTHER TESTSGraphic LogMATERIAL DESCRIPTION
Topsoil
Gravel Bar
tan clay loam
sandy gravels
groundwater at 9'8"; bottom of pit.
Installed 12' perforated pipe groundwater
monitoring well. Relative ConsistencyDepth (feet)0
5
10
15
20
25
30 Sample TypeSampling Resistance blows/6"Z:\Jobs\JBS 2014\014095CR\borings.bg4[CRTemplate.tpl]Sheet 1 of 1
Project:Lakes at Valley West
Project Location:Bozeman, MT
Project Number:014095CR
Log of Boring TH-2
Date(s)
Drilled 9-9-2014
Drilling
Method Excavator
Drill Rig
Type Cat 325BL
Groundwater Level
and Date Measured Not Observed
Borehole
Backfill spoils
Logged By DB
Drill Bit
Size/Type
Drilling
Contractor SIME
Sampling
Method(s)
Location Northeast portion of property (east of Laurel Pkwy)
Checked By AP
Total Depth
of Borehole 5'
Approximate
Surface Elevation
Hammer
Data
Material TypeFill
OL-ML
CL
GP
REMARKS AND OTHER TESTSGraphic LogMATERIAL DESCRIPTION
Topsoil & gravels fill
topsoil
Tan clay loam;
p-test = 30 and minimal penetration; very
stiff.
native sandy gravels Relative ConsistencyDepth (feet)0
5
10
15
20
25
30 Sample TypeSampling Resistance blows/6"Z:\Jobs\JBS 2014\014095CR\borings.bg4[CRTemplate.tpl]Sheet 1 of 1
Project:Lakes at Valley West
Project Location:Bozeman, MT
Project Number:014095CR
Log of Boring TH-3
Date(s)
Drilled 9-9-2014
Drilling
Method Excavator
Drill Rig
Type Cat 325BL
Groundwater Level
and Date Measured 12'
Borehole
Backfill spoils
Logged By DB
Drill Bit
Size/Type
Drilling
Contractor SIME
Sampling
Method(s)
Location Northeast portion of property (west of Laurel Pkwy)
Checked By AP
Total Depth
of Borehole 12'
Approximate
Surface Elevation
Hammer
Data
Material TypeFill
OL-ML
CL
GP
REMARKS AND OTHER TESTSGraphic LogMATERIAL DESCRIPTION
Sandy gravels
Dark black silt loam topsoil
tan clay loam
sandy gravels
groundwater at 12'; bottom of pit.Relative ConsistencyDepth (feet)0
5
10
15
20
25
30 Sample TypeSampling Resistance blows/6"Z:\Jobs\JBS 2014\014095CR\borings.bg4[CRTemplate.tpl]Sheet 1 of 1
Project:Lakes at Valley West
Project Location:Bozeman, MT
Project Number:014095CR
Log of Boring TH-4
Date(s)
Drilled 9-9-2014
Drilling
Method Excavator
Drill Rig
Type Cat 325BL
Groundwater Level
and Date Measured 11'10"
Borehole
Backfill spoils
Logged By DB
Drill Bit
Size/Type
Drilling
Contractor SIME
Sampling
Method(s)
Location North portion of property (west of Laurel Pkwy)
Checked By AP
Total Depth
of Borehole 11'10"
Approximate
Surface Elevation
Hammer
Data
Material TypeFill
OL-ML
CL
GP
REMARKS AND OTHER TESTSGraphic LogMATERIAL DESCRIPTION
Marbled fill; pockets of topsoil mixed with
sandy gravels.
Dark Black silt loam topsoil
tan clay loam
sandy gravels
Groundwater at 11'10", bottom of pit.Relative ConsistencyDepth (feet)0
5
10
15
20
25
30 Sample TypeSampling Resistance blows/6"Z:\Jobs\JBS 2014\014095CR\borings.bg4[CRTemplate.tpl]Sheet 1 of 1
Project:Lakes at Valley West
Project Location:Bozeman, MT
Project Number:014095CR
Log of Boring TH-5
Date(s)
Drilled 9-9-2014
Drilling
Method Excavator
Drill Rig
Type Cat 325BL
Groundwater Level
and Date Measured 11'8"
Borehole
Backfill spoils
Logged By DB
Drill Bit
Size/Type
Drilling
Contractor SIME
Sampling
Method(s)
Location North portion of property (west of Laurel Pkwy)
Checked By AP
Total Depth
of Borehole 11'8"
Approximate
Surface Elevation
Hammer
Data
Material TypeFill
REMARKS AND OTHER TESTSGraphic LogMATERIAL DESCRIPTION
Fill consisting of loamy gravels with
organics; marbled with tan clay loam.
groundwater @ 11'8", bottom of pit.
15'8" perforated groundwater monitoring well
installed.
p-test @ 6' = 20; over 6" of penetration. Relative ConsistencyDepth (feet)0
5
10
15
20
25
30 Sample TypeSampling Resistance blows/6"Z:\Jobs\JBS 2014\014095CR\borings.bg4[CRTemplate.tpl]Sheet 1 of 1
Project:Lakes at Valley West
Project Location:Bozeman, MT
Project Number:014095CR
Log of Boring TH-6
Date(s)
Drilled 9-9-2014
Drilling
Method Excavator
Drill Rig
Type Cat 325BL
Groundwater Level
and Date Measured 5'0"
Borehole
Backfill spoils
Logged By DB
Drill Bit
Size/Type
Drilling
Contractor SIME
Sampling
Method(s)
Location west-central portion of property (just east of Westgate Ave)
Checked By AP
Total Depth
of Borehole 5'0"
Approximate
Surface Elevation
Hammer
Data
Material TypeOL-ML
GP
REMARKS AND OTHER TESTSGraphic LogMATERIAL DESCRIPTION
silt loam topsoil with organics
fill consisting of tightly packed gravels in
clay loam matrix.
groundwater @ 5'; bottom of pit. Relative ConsistencyDepth (feet)0
5
10
15
20
25
30 Sample TypeSampling Resistance blows/6"Z:\Jobs\JBS 2014\014095CR\borings.bg4[CRTemplate.tpl]Sheet 1 of 1
Project:Lakes at Valley West
Project Location:Bozeman, MT
Project Number:014095CR
Log of Boring TH-7
Date(s)
Drilled 9-9-2014
Drilling
Method Excavator
Drill Rig
Type Cat 325BL
Groundwater Level
and Date Measured 4'6"
Borehole
Backfill spoils
Logged By DB
Drill Bit
Size/Type
Drilling
Contractor SIME
Sampling
Method(s)
Location southwest portion of property (west of Westgate Ave)
Checked By AP
Total Depth
of Borehole 4'6"
Approximate
Surface Elevation
Hammer
Data
Material TypeOL-ML
GP
GP
REMARKS AND OTHER TESTSGraphic LogMATERIAL DESCRIPTION
dark silt loam topsoil
Brown sandy gravels
gravels in olive grey clay loam matrix
groundwater @ 4'6"; bottom of pit at 5'Relative ConsistencyDepth (feet)0
5
10
15
20
25
30 Sample TypeSampling Resistance blows/6"Z:\Jobs\JBS 2014\014095CR\borings.bg4[CRTemplate.tpl]Sheet 1 of 1
Project:Lakes at Valley West
Project Location:Bozeman, MT
Project Number:014095CR
Log of Boring TH-8
Date(s)
Drilled 9-9-2014
Drilling
Method Excavator
Drill Rig
Type Cat 325BL
Groundwater Level
and Date Measured 3'6"
Borehole
Backfill spoils
Logged By DB
Drill Bit
Size/Type
Drilling
Contractor SIME
Sampling
Method(s)
Location southwest portion of property (west of Westgate Ave)
Checked By AP
Total Depth
of Borehole 4'
Approximate
Surface Elevation
Hammer
Data
Material TypeGP
REMARKS AND OTHER TESTSGraphic LogMATERIAL DESCRIPTION
Tightly packed sandy gravels; 6" of
rootstock.
groundwater at 3.5'; bottom of pit at 4'. Relative ConsistencyDepth (feet)0
5
10
15
20
25
30 Sample TypeSampling Resistance blows/6"Z:\Jobs\JBS 2014\014095CR\borings.bg4[CRTemplate.tpl]Sheet 1 of 1
Project:Lakes at Valley West
Project Location:Bozeman, MT
Project Number:014095CR
Log of Boring TH-9
Date(s)
Drilled 9-9-2014
Drilling
Method Excavator
Drill Rig
Type Cat 325BL
Groundwater Level
and Date Measured 5'8"
Borehole
Backfill spoils
Logged By DB
Drill Bit
Size/Type
Drilling
Contractor SIME
Sampling
Method(s)
Location southeast portion of pond (east of Laurel Pkwy)
Checked By AP
Total Depth
of Borehole 5'8"
Approximate
Surface Elevation
Hammer
Data
Material TypeOL-ML
GP
REMARKS AND OTHER TESTSGraphic LogMATERIAL DESCRIPTION
dark silt loam topsoil; rootstock to 2'
sandy gravels
groundwater @ 5'9"; bottom of pit. Zone of
moisture observed up to 3' b.g.s Relative ConsistencyDepth (feet)0
5
10
15
20
25
30 Sample TypeSampling Resistance blows/6"Z:\Jobs\JBS 2014\014095CR\borings.bg4[CRTemplate.tpl]Sheet 1 of 1
Project:Lakes at Valley West
Project Location:Bozeman, MT
Project Number:014095CR
Log of Boring TH-10
Date(s)
Drilled 9-9-2014
Drilling
Method Excavator
Drill Rig
Type Cat 325BL
Groundwater Level
and Date Measured 5'8"
Borehole
Backfill spoils
Logged By DB
Drill Bit
Size/Type
Drilling
Contractor SIME
Sampling
Method(s)
Location southeast portion of property (west of Laurel Pkwy)
Checked By AP
Total Depth
of Borehole 5'8"
Approximate
Surface Elevation
Hammer
Data
Material TypeOL-ML
CL
REMARKS AND OTHER TESTSGraphic LogMATERIAL DESCRIPTION
dark silt loam topsoil; rootstock to 6'
tan clay loam
sandy gravels
groundwater @ 7', bottom of pit.
Installed 9' perforated groundwater
monitoring well. Relative ConsistencyDepth (feet)0
5
10
15
20
25
30 Sample TypeSampling Resistance blows/6"Z:\Jobs\JBS 2014\014095CR\borings.bg4[CRTemplate.tpl]Sheet 1 of 1
Project:Lakes at Valley West
Project Location:Bozeman, MT
Project Number:014095CR
Log of Boring TH-11
Date(s)
Drilled 9-10-2014
Drilling
Method Excavator
Drill Rig
Type Cat 325BL
Groundwater Level
and Date Measured 9'5"
Borehole
Backfill spoils
Logged By DB
Drill Bit
Size/Type
Drilling
Contractor SIME
Sampling
Method(s)
Location northwest portion of property (east of Westgate Ave, edge of berm)
Checked By AP
Total Depth
of Borehole 9'5"
Approximate
Surface Elevation
Hammer
Data
Material TypeFill
Fill
CL
GP
REMARKS AND OTHER TESTSGraphic LogMATERIAL DESCRIPTION
fill consisting of gravelly spoils; wood and
trash debris observed.
fill consisting of loam with gravels;
p-test exceeds scale, very stiff to hard
consistency.
tan clay loam;
p-test = 0; easily penetrated, soft
consistency.
sandy gravels
groundwater @ 9'5", bottom of pit. Relative ConsistencyDepth (feet)0
5
10
15
20
25
30 Sample TypeSampling Resistance blows/6"Z:\Jobs\JBS 2014\014095CR\borings.bg4[CRTemplate.tpl]Sheet 1 of 1
Project:Lakes at Valley West
Project Location:Bozeman, MT
Project Number:014095CR
Log of Boring TH-12
Date(s)
Drilled 9-10-2014
Drilling
Method Excavator
Drill Rig
Type Cat 325BL
Groundwater Level
and Date Measured 4'0"
Borehole
Backfill spoils
Logged By DB
Drill Bit
Size/Type
Drilling
Contractor SIME
Sampling
Method(s)
Location northweast portion of property (nearly in line of action of Westgate Ave)
Checked By AP
Total Depth
of Borehole 4'0"
Approximate
Surface Elevation
Hammer
Data
Material TypeOL-ML
CL
GP
REMARKS AND OTHER TESTSGraphic LogMATERIAL DESCRIPTION
brown loam topsoil
grey lean clay loam; stiff consistency, near
optimum moisture content
sandy gravels
groundwater @ 4', bottom of pit. Relative ConsistencyDepth (feet)0
5
10
15
20
25
30 Sample TypeSampling Resistance blows/6"Z:\Jobs\JBS 2014\014095CR\borings.bg4[CRTemplate.tpl]Sheet 1 of 1
Project:Lakes at Valley West
Project Location:Bozeman, MT
Project Number:014095CR
Log of Boring TH-13
Date(s)
Drilled 9-10-2014
Drilling
Method Excavator
Drill Rig
Type Cat 325BL
Groundwater Level
and Date Measured surface
Borehole
Backfill spoils
Logged By DB
Drill Bit
Size/Type
Drilling
Contractor SIME
Sampling
Method(s)
Location northweast portion of property (in sag spot)
Checked By AP
Total Depth
of Borehole 1'
Approximate
Surface Elevation
Hammer
Data
Material TypeGP
REMARKS AND OTHER TESTSGraphic LogMATERIAL DESCRIPTION
sandy gravels
groundwater at surface. Relative ConsistencyDepth (feet)0
5
10
15
20
25
30 Sample TypeSampling Resistance blows/6"Z:\Jobs\JBS 2014\014095CR\borings.bg4[CRTemplate.tpl]Sheet 1 of 1
Project:Lakes at Valley West
Project Location:Bozeman, MT
Project Number:014095CR
Log of Boring TH-14
Date(s)
Drilled 9-10-2014
Drilling
Method Excavator
Drill Rig
Type Cat 325BL
Groundwater Level
and Date Measured 9'
Borehole
Backfill spoils
Logged By DB
Drill Bit
Size/Type
Drilling
Contractor SIME
Sampling
Method(s)
Location northern portion of property (between Westgate Ave & Laurel Pkwy)
Checked By AP
Total Depth
of Borehole 9'
Approximate
Surface Elevation
Hammer
Data
Material TypeFill
CL
GP
REMARKS AND OTHER TESTS
sampled 5gal. bucket of black loam fill material at 4.5'
4.5' to 5' thin-wall sample taken. Graphic LogMATERIAL DESCRIPTION
fill material consisting of silt loam marbled
with lean clay; no gravels.
p-test not uniform, voids exist;
p-test @ 40" b.g.s = 15 to 20
p-test @ 67" = 15
tan clay loam
p-test @ 8' = 10
6" minus sandy gravels Relative ConsistencyDepth (feet)0
5
10
15
20
25
30 Sample TypeSampling Resistance blows/6"Z:\Jobs\JBS 2014\014095CR\borings.bg4[CRTemplate.tpl]Sheet 1 of 1
Project:Lakes at Valley West
Project Location:Bozeman, MT
Project Number:014095CR
Log of Boring TH-15
Date(s)
Drilled 9-10-2014
Drilling
Method Excavator
Drill Rig
Type Cat 325BL
Groundwater Level
and Date Measured 2'
Borehole
Backfill spoils
Logged By DB
Drill Bit
Size/Type
Drilling
Contractor SIME
Sampling
Method(s)
Location northern portion of property (between Westgate Ave & Laurel Pkwy)
Checked By AP
Total Depth
of Borehole 2'
Approximate
Surface Elevation
Hammer
Data
Material TypeOL-ML
GP
REMARKS AND OTHER TESTSGraphic LogMATERIAL DESCRIPTION
dark silt loam topsoil
gravels in grey clay matrix.
groundwater @ 2', bottom of pit. Relative ConsistencyDepth (feet)0
5
10
15
20
25
30 Sample TypeSampling Resistance blows/6"Z:\Jobs\JBS 2014\014095CR\borings.bg4[CRTemplate.tpl]Sheet 1 of 1
Project:Lakes at Valley West
Project Location:Bozeman, MT
Project Number:014095CR
Key to Log of Boring
Material TypeREMARKS AND OTHER TESTSGraphic LogMATERIAL DESCRIPTION Relative ConsistencyDepth (feet)Sample TypeSampling Resistance blows/6"1 2 3 4 5 6 7 8
COLUMN DESCRIPTIONS
1 Depth (feet): Depth in feet below the ground surface.
2 Material Type: Type of material encountered.
3 Graphic Log: Graphic depiction of the subsurface material
encountered.
4 MATERIAL DESCRIPTION: Description of material encountered.
May include consistency, moisture, color, and other descriptive
text.
5 Sampling Resistance blows/6": Number of blows to advance driven
sampler six inches beyond seating interval using the hammer
identified on the boring log.
6 Sample Type: Type of soil sample collected at the depth interval
shown.
7 Relative Consistency: Relative consistency of the subsurface
material.
8 REMARKS AND OTHER TESTS: Comments and observations
regarding drilling or sampling made by driller or field personnel.
FIELD AND LABORATORY TEST ABBREVIATIONS
CHEM: Chemical tests to assess corrosivity
COMP: Compaction test
CONS: One-dimensional consolidation test
LL: Liquid Limit, percent
PI: Plasticity Index, percent
SA: Sieve analysis (percent passing No. 200 Sieve)
UC: Unconfined compressive strength test, Qu, in ksf
WA: Wash sieve (percent passing No. 200 Sieve)
MATERIAL GRAPHIC SYMBOLS
Lean CLAY, CLAY w/SAND, SANDY CLAY (CL)AF
Poorly graded GRAVEL (GP)
TYPICAL SAMPLER GRAPHIC SYMBOLS
Auger sampler
Bulk Sample
3-inch-OD California w/
brass rings
CME Sampler
Grab Sample
2.5-inch-OD Modified
California w/ brass liners
Pitcher Sample
2-inch-OD unlined split
spoon (SPT)
Shelby Tube (Thin-walled,
fixed head)
OTHER GRAPHIC SYMBOLS
Water level (at time of drilling, ATD)
Water level (after waiting)
Minor change in material properties within a
stratum
Inferred/gradational contact between strata
?Queried contact between strata
GENERAL NOTES
1: Soil classifications are based on the Unified Soil Classification System. Descriptions and stratum lines are interpretive, and actual lithologic changes may be
gradual. Field descriptions may have been modified to reflect results of lab tests.
2: Descriptions on these logs apply only at the specific boring locations and at the time the borings were advanced. They are not warranted to be representative
of subsurface conditions at other locations or times.Z:\Jobs\JBS 2014\014095CR\borings.bg4[CRTemplate.tpl]Figure B-1
Sheet 1 of 1