CC - Geotech ReportConstruction Materials Testing & Special Inspection
Geotechnical Engineering
ALLWEBT Environmental Consulting
Testing & Engineering Non -Destructive Testing
Welder Certification
January 12, 2018
Chad Hamel
Woodside Harris, LLC
1025 S. Bridgeway Place, Suite 290
Eagle, Idaho 83616
chamel(a)-boisehunterhomes.com
RE: Geotechnical Evaluation
Sky Mesa Commons
Meridian, Idaho
ALLWEST Project No. 517-69OG
Mr. Hamel:
ALLWEST Testing & Engineering, Inc. (ALLWEST) has completed the authorized
geotechnical evaluation for the proposed Sky Mesa Commons Subdivision to be located in
Meridian, Idaho. The purpose of this evaluation was to characterize subsurface soil
conditions at the site and provide geotechnical recommendations to assist planning,
design and construction for the proposed development. The attached report presents the
results of our field evaluation, laboratory testing and our recommendations.
We appreciate the opportunity to be of service to Woodside Harris, LLC. If you have any
questions or need additional information, please do not hesitate to call us at (208) 895-
7898.
Sincerely,
ALLWEST Testing & EngineorlinZ.Linc.
Im
® `14253
CSS
Adrian Mascorro, P.E. \!\�f
Engineering Manager 4�M
255 North Linder Road, Ste. 100, Meridian, ID 83642
Phone: (208) 895-7898 a Fax: (208) 898-3959
Hayden, ID a Lewiston, ID a Meridian, ID a Spokane Valley, WA
www.allwesttesting.com
GEOTECHNICAL EVALUATION
SKY MESA COMMONS
MERIDIAN, IDAHO
ALLWEST PROJECT NO. 517-6906
January 12, 2018
Prepared for:
Chad Hamel
Woodside Harris, LLC
1025 S. Bridgeway Place, Suite 290
Eagle, Idaho 83616
Prepared By:
ALLWEST Testing & Engineering, Inc.
255 North Linder Road, Suite 100
Meridian, Idaho 83642
WWW.ALLWESTTESTING.COM
TABLE OF CONTENTS
ALLWEST Project No. 517-69OG
Sky Mesa Commons Subdivision
Meridian, Idaho
Page
1.0 SCOPE OF SERVICES........................................................................................1
2.0 PROJECT UNDERSTANDING.............................................................................1
3.0 EVALUATION PROCEDURES............................................................................ 2
4.0 SITE CONDITIONS.............................................................................................. 2
4.1 General Geologic Conditions.............................................................................
2
4.2 General Soil Conditions.....................................................................................2
5.0 EXPLORATION AND SAMPLING.......................................................................2
5.1 Subsurface Soil Conditions...............................................................................
3
5.2 Subsurface Water..............................................................................................
3
6.0 LABORATORY TESTING....................................................................................
4
7.0 CONCLUSIONS AND RECOMMENDATIONS....................................................4
7.1 Planning Considerations...................................................................................4
7.2 Grading.............................................................................................................4
7.3 Site Preparation.................................................................................................5
7.4 Subgrade Stabilization......................................................................................
5
7.5 Excavation.........................................................................................................
6
7.6 Materials............................................................................................................6
7.7 Fill Placement and Compaction.........................................................................
7
7.8 Utility Trenches..................................................................................................
7
7.9 Wet Weather Construction................................................................................
8
7.10 Cold Weather Construction.............................................................................
8
7.11 Stormwater Disposal.......................................................................................
8
7.12 Asphalt Pavement...........................................................................................
9
8.0 ADDITIONAL RECOMMENDED SERVICES.....................................................10
9.0 EVALUATION LIMITATIONS..............................................................................10
Appendix A — Site Vicinity Map, Exploration Location Plan
Appendix B — Test Pit Logs, Unified Soil Classification System
Appendix C — Laboratory Test Results
Construction Materials Testing & Special Inspection
Geotechnical Engineering
ALLWEST Testing &Engineering Environmental Consulting
Non -Destructive Testing
Welder Certification
Geotechnical Evaluation
Sky Mesa Commons Subdivision
Meridian, Idaho
ALLWEST Testing & Engineering, Inc. (ALLWEST) has completed the authorized
geotechnical evaluation for the proposed Sky Mesa Commons Subdivision located in
Meridian, Idaho. The general location of the project is shown on Figure 1 — Site Vicinity
Map in Appendix A of this report. The purpose of this evaluation was to identify
subsurface soil conditions at the site and provide opinions and recommendations with
respect to the proposed construction, relative to earthwork, asphalt pavements, and
stormwater disposal. This report details the results of the field evaluation and presents
our recommendations to assist planning, design and construction.
1.0 SCOPE OF SERVICES
To complete our evaluation, we accomplished the following scope of services:
1) Notified Idaho Digline to pre -mark underground utilities at the site prior to
exploration.
2) Subcontracted a backhoe and operator to observe the excavation of 6 test pits
at the site on December 19, 2017. We visually described and classified soils
observed within the test pits referencing the Unified Soil Classification System
(USCS), and we logged the subsurface profiles. We obtained select disturbed
samples of the soils encountered within the test pits for laboratory testing.
3) Performed field seepage testing within select test pits, and installed slotted PVC
pipes within the 6 test pits observed, for future groundwater monitoring.
4) Performed laboratory tests on select soil samples to assess some of the soil
engineering properties and characteristics.
5) Reviewed the results of the field evaluation and laboratory testing with respect
to the proposed construction.
6) Performed engineering analyses and prepared recommendations to assist
project planning, design and construction.
7) Prepared this report.
We provided our services in general accordance with our geotechnical proposal (517-
690P), dated December 11, 2017.
2.0 PROJECT UNDERSTANDING
Based on communication with you, we understand plans for the approximate 18 -acre
portion of the overall site will consist of a subdivision development with single-family
residential homes. The development will include associated infrastructure, asphalt
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Sky Mesa Commons Subdivision Page 2
Meridian, Idaho
paved roadways, and stormwater disposal facilities. We did not review a preliminary
grading plan for the site, but we anticipate cut and fill for the site to be 2 feet or less.
3.0 EVALUATION PROCEDURES
To complete this evaluation, we observed the excavation of 6 test pits on December
19, 2017, utilizing a Case 580C excavator with a 3 -foot -wide bucket. The approximate
locations of the test pits are shown on Figure A-2 — Exploration Location Plan in
Appendix A of this report. We obtained select soil samples for laboratory testing, and
installed slotted PVC pipes within every test pit for future groundwater monitoring.
4.0 SITE CONDITIONS
At the time of our field exploration, the site was undeveloped and consisted of a grass
sod field. The site was bordered by East Taconic Drive to the north, and agricultural
land to the west, south, and east.
4.1 General Geologic Conditions
The geologic conditions at the site are mapped as Sandy Alluvium of Side -Stream
Valleys and Gulches consisting of medium to coarse sand interbedded with silty fine
sand and silt, with some clay and calcium carbonate, on the "Geologic Map of the Boise
Valley and Adjoining Area, Western Snake River Plain, Idaho", prepared by Othberg
and Stanford, 1992.
4.2 General Soil Conditions
The USDA Natural Resources Conservation Service (NRCS) has mapped the soil on
the property as Xeric Haplocalcids, Power silt loam, and Purdam silt loam of stream
terraces and lava plains. The parent materials are mixed alluvium, loess and/or
lacustrine deposits consisting of loam, silt loam, silty clay loam, sandy loam, cemented
material, and/or gravelly sand.
The soils encountered in the test pits are generally consistent with the NRCS and
geologic mapping.
5.0 EXPLORATION AND SAMPLING
We observed the excavation of 6 total test pits at the approximate locations shown on
Figure A-2 — Exploration Location Plan. Woodside Harris, LLC (Woodside Harris) had
the test pits surveyed and pre -staked, based on predetermined exploration locations
between ALLWEST and Woodside Harris. Woodside Harris also coordinated that the
exploration areas were stripped of grass sod before our site exploration, to limit
disturbance to existing grass sod.
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Sky Mesa Commons Subdivision
Meridian, Idaho
ALLWEST Project No. 517-69OG
Page 3
We visually described, classified and logged the soil conditions observed in the test
pits in general accordance with ASTM D 2487 and D 2488. We obtained select
disturbed soil samples from exploration locations. We also installed slotted PVC pipes
in all test pits for future groundwater monitoring.
At the conclusion of the field evaluation, the test pits were loosely backfilled with
excavated soil to approximate ground surface elevations. The backfill will densify with
time. If test pits are located below proposed structure, pavement or flatwork areas, the
test pit backfill should be re -excavated and compacted to a minimum of 95 percent of
the maximum dry density as determined by ASTM D1557 (modified Proctor).
5.1 Subsurface Soil Conditions
The majority of the site consists of approximately 3 inches of moderate roots and
vegetation at the surface. Surficial soil consists of lean clay soil, overlying sandy silt
which was overlying poorly -graded sand with gravel.
Specific descriptions of the soil types observed during our field exploration follow:
Lean clay (native) — We observed lean clay with sand to depths of 13/ to 3 feet. The
clay with sand soil appeared brown, very stiff to hard, and moist.
Sandy silt — Underlying clay with sand soil, we observed sandy silt to depths of 41/2 to 8
feet. The sandy silt appeared tan, medium dense, and moist.
Poorly -graded sand with gravel — Underlying sandy silt, we observed poorly -graded
sand with gravel to test pit termination depths of 91/2 to 13 feet. The poorly -graded sand
with gravel appeared tan, medium dense, and moist to saturated.
Detailed soil descriptions, depths, and notes are presented on individual test pit logs in
Appendix B of this report. The descriptive soil terms used on the test pit logs and in this
report can be referenced by the USCS. A copy of the USCS is also included in Appendix
B. The subsurface conditions may vary between exploration locations. Such changes
in conditions may not be apparent until construction. If the subsurface conditions do
change significantly from those observed, the construction timing, plans and costs may
change.
5.2 Subsurface Water
At the time of exploration, we observed groundwater within each test pit observed, with
exception of test pit TP -5. Where encountered, groundwater was observed at
approximately 7 to 10% feet below existing ground surface. However, changes in
irrigation, precipitation, site grading, and other factors may also impact the depth to
groundwater. Fluctuations in the groundwater levels should be expected. Refer to
individual test pit logs in Appendix B for groundwater levels at the time of exploration.
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5.3 Seepage Testing
ALLWEST Project No. 517-69OG
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We performed field seepage testing in test pit TP -4 within the poorly -graded sand with
gravel at a depth of 9 feet. We measured a field seepage rate of greater than 30 inches
per hour (in/hr) within the sand with gravel soil. The sand with gravel soil contained
consistent properties throughout the site. Refer to Section 7.11 Stormwater Disposal
for Stormwater disposal recommendations.
6.0 LABORATORY TESTING
We performed laboratory testing to supplement field classifications and to assess
some of the soil engineering properties and parameters. The laboratory tests
conducted included moisture content (ASTM D 2216), gradation (ASTM D 1140), and
Atterberg limits (ASTM D 4318). Laboratory test results are summarized in Appendix
C. The laboratory test results are also summarized on exploration logs in Appendix B.
7.0 CONCLUSIONS AND RECOMMENDATIONS
The following recommendations are presented to assist with planning, design and
construction of the proposed development, relative to earthwork and infrastructure
development. These recommendations are based on our understanding of the
proposed construction, the conditions observed within exploration locations, laboratory
test results, and engineering analysis. If the scope of construction changes, or if
conditions are encountered during construction that differ from those described herein,
we should be notified so we can review our recommendations and provide revisions,
if necessary.
7.1 Planning Considerations
If ALLWEST's exploratory test pits are located below future structures, pavement or
flatwork areas, those loose backfill soil areas should be re -excavated and replaced
with compacted soil, as required in this report. Contingencies should be made during
earthwork site grading, prior to any fill placement, to ensure any loose test pit backfill
areas are over -excavated and replaced with compacted fill soil.
We observed roots and vegetation to depths of 3 inches. Surficial soil with heavy roots
should be stripped prior to any fill placement or construction. Any stripped topsoil
containing organics, vegetation, roots, or unsuitable fill material, should be stockpiled
separately and only used as landscape fill, or discarded off-site.
7.2 Grading
We have assumed cut and fill for site grading to be 2 feet or less. We should be notified
if actual site grading varies significantly from this stated information.
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7.3 Site Preparation
ALLWEST Project No. 517-69OG
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Prior to conducting site grading, surficial soil containing vegetation, roots and organics,
should be removed below proposed pavement areas, and any other development
areas. We anticipate approximately 3 inches of site stripping will be required for the
majority of the site to remove farmland vegetation and roots. However, this depth may
vary and will not be fully known until construction.
After site stripping, and prior to placing site grading fill, the exposed subgrade should
be proof -rolled with a minimum 5 -ton vibratory roller, to confirm subgrade stability. This
will also assist in identifying any soft or loose soil zones associated with previous test
pit excavations on-site. If the subgrade is observed to significantly deflect/pump, it
should be over -excavated to firm, non -yielding soil and replaced with properly
compacted fill, or stabilized as recommended in the following Subgrade Stabilization
section.
7.4 Subgrade Stabilization
If the subgrade is observed to pump or deflect significantly during grading, it should be
stabilized prior to placement of fill. The subgrade may be stabilized using either
crushed, angular cobble, or with geosynthetic reinforcement in conjunction with
imported granular structural fill. The required thicknesses of crushed cobble or
structural fill (used in conjunction with geosynthetic reinforcement) will be dependent
on the construction traffic loading which is unknown at this time. Therefore, a certain
degree of trial and error may be required during construction to verify the
recommended stabilization section thicknesses.
If crushed, angular cobble is selected to stabilize the subgrade, it should have a
maximum particle size of 8 inches and should be relatively free of sand and fines (silt
and clay). The first layer of cobble should be placed in an 18 -inch -thick loose lift and
trafficked with tracked and vibratory drum compaction equipment until it is observed to
densify. If vibratory compaction destabilizes the subgrade, it should be discontinued. If
cobble is placed in a confined excavation, it should be mechanically densified from
outside the excavation with vibratory compaction equipment.
If geosynthetic reinforcement is selected, it should consist of Tensar TX -160 or
equivalent. Alternatives to Tensar TX -160 should be approved by the geotechnical
engineer prior to use on site. The following recommendations are provided for
subgrade stabilization using geosynthetic reinforcement.
• Geosynthetic reinforcement materials should be placed on a properly prepared
subgrade with smooth surface. Loose and disturbed soil should be removed
prior to placement of geosynthetic reinforcement materials.
A minimum weight 4 -ounce, non -woven filter fabric should be placed on the
properly prepared subgrade. The geosynthetic reinforcement should be placed
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directly on top of the filter fabric. The filter fabric and geosynthetic reinforcement
should be unrolled in the primary direction of fill placement and should be over-
lapped at least 3 feet.
• The geosynthetic materials should be pulled taut to remove slack.
Construction equipment should not be operated directly on the geosynthetic
materials. Fill should be placed from outside the excavation to create a pad to
operate equipment on. We recommend a minimum of 12 inches of structural fill
be placed over the geosynthetic reinforcement before operating construction
equipment on the fill. Low pressure, track -mounted equipment should be used
to place fill over the geosynthetic reinforcement.
Fill placed directly over the geosynthetic reinforcement should be properly
moisture conditioned prior to placement and should meet the structural fill
criteria in the table in section 7.6 Materials.
The fill material should be properly compacted. Care should be taken with the
use of vibratory compaction equipment. Vibration should be discontinued if it
reduces the subgrade stability.
A representative of ALLWEST should be on-site during subgrade stabilization to verify
our recommendations are followed and to provide additional recommendations, as
needed.
7.5 Excavation
Excavation of the on-site soil can be accomplished with typical excavation equipment.
We recommend excavations greater than 4 feet deep be sloped no steeper than 1.5:1
(horizontal to vertical). Alternatively, deeper excavations may be shored or braced in
accordance with OSHA specifications and local codes. Regarding trench wall support,
the site soil is considered Type C soil according to Occupational Safety and Health
Administration (OSHA) guidelines. Ultimately, the contractor is responsible for site
safety, excavation configurations and following OSHA guidelines.
7.6 Materials
Stripped soils are only suitable for use in non-structural landscape areas. Import
materials should be granular soil free of organics, debris and other deleterious material
and meet the following recommendations. Import materials should be approved by
ALLWEST prior to delivery to the site.
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Fill Type
Recommendations
Subgrade
Maximum size <_ 6 inches;
Site Grading
Retained on 3% -inch Sieve < 30%;
Utility Trench Backfill
Liquid limit < 50%
Base Course/ Subbase
Maximum size <_ 6 inches;
Granular Structural Fill and
Retained on 3% -inch Sieve < 30%;
Subbase Gravel
Passing No. 200 Sieve <_ 15%; Non -plastic
Alternatively, meet ISPWC section 801 6 inches)
Maximum size:5 1 inches;
Retained on 3% -inch Sieve <010%;
Crushed Base Course
Passing No. 200 Sieve < 10%; Non -plastic
Alternatively, meet ISPWC section 802 (Type 1)
Maximum size <_ 2 inches;
Retained on 3% -inch Sieve <30%;
Utility Trench Backfill
Passing No. 200 Sieve:5 10%; Non -plastic
Alternatively, meet ISPWC section 305 (Type 1)
7.7 Fill Placement and Compaction
Fill should be placed in lift thicknesses which are appropriate for the compaction
equipment used. Typically, 8 -inch -thick loose -lifts are appropriate for typical rubber tire
and steel drum compaction equipment. Lift thicknesses should be reduced to 4 inches
for hand -operated compaction equipment. Fill should be moisture conditioned to within
2 percentage points of the optimum moisture content prior to placement to facilitate
compaction. Fill should be compacted to the following percentages of the maximum
dry density as determined by ASTM D 1557 (modified Proctor).
Fill Area
Compaction
Subgrade
Proof -roll*
Site Gradin / Structural Fill / Pavements
95
Utility Trench Backfill
95
Base Course/ Subbase
95
* Proof -roll should be observed by a representative OT HLLvvca i
7.8 Utility Trenches
Support soil for underground utilities will likely consist of lean clay with sand, sandy silt,
or poorly -graded sand with gravel. It is our opinion these soils should generally provide
adequate support for utilities. Consideration should be given to backfilling utility trench
excavations in pavement areas with imported fill which meets the recommendations
provided in section 7.6 above. The on-site soils may be difficult to compact in utility
trenches. If utility pipe support soils are soft or yielding at the time of construction,
excavation of the support soils and replacement with a more competent structural fill
may be necessary. If support soils yield at the time of construction, we should be
notified in order to observe these soils and provide additional recommendations, if
necessary.
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7.9 Wet Weather Construction
We recommend earthwork for this site be scheduled for the drier seasons of the year.
If construction is undertaken in wet periods of the year, it will be important to slope the
ground surface to provide drainage away from construction. If construction occurs
during or immediately after excessive precipitation, it may be necessary to over -
excavate and replace saturated subgrade soil which might otherwise be suitable.
The on-site clayey and silty soils are sensitive to disturbance when wet. If these soils
become wet and unstable, we recommend construction traffic is minimized where
these soils are exposed. Low ground pressure (tracked) equipment should be used to
minimize disturbance. Soft and disturbed subgrade areas should be excavated to
undisturbed soil and backfilled with structural fill.
In addition, it should be noted the on-site soils tend to have notable adhesion when
wet and may be easily transported off-site by construction traffic.
7.10 Cold Weather Construction
The on-site soils are considered to be frost susceptible. If site grading and construction
are anticipated during cold weather, we recommend good winter construction practices
be observed. Snow and ice should be removed from excavated and fill areas prior to
additional earthwork or construction. Pavement and flatwork portions of the
construction should not be placed on frozen ground; nor should the supporting soils be
permitted to freeze during or after construction. Frozen soils should not be used as fill.
7.11 Stormwater Disposal
During our investigation, we performed field seepage testing within test pit TP -4 within
poorly -graded sand with gravel, at a depth of 9 feet. We measured a field seepage rate
of greater than 30 in/hr within sand with gravel soil.
Based on our field seepage testing and observations, and consistent soil properties of
the sand with gravel, we recommend stormwater disposal occur within poorly -graded
sand with gravel, encountered at depths of greater than 9Y2 feet below existing ground
surfaces. The following allowable design seepage rate may be utilized for stormwater
disposal on-site:
• Poorly -graded sand with gravel 8 in/hr
Stormwater disposal facilities should be constructed a minimum of 1 foot into poorly -
graded sand with gravel. Seepage disposal facilities may consist of sand windows (or
chimneys) to reach permeable soils. Seepage beds or sand windows should be "burrito
wrapped" or otherwise maintain a separation/filter fabric between native fine-grained
soils and drain rock/filter sand to help prevent fine soil migration into drainable/filtering
media. ALLWEST should observe stormwater disposal facility subgrades, to establish
if suitable receiving soil is encountered, to confirm the recommended seepage rate,
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and to ensure the separation/filter fabric has been properly installed. Refer to test pit
logs in Appendix A for soil contact depths.
We observed groundwater at the time of exploration within test pits at approximate
depths of 7 to 10% feet. Refer to individual test pit logs in Appendix B for measured
depths to groundwater at the time of exploration. We installed vertical PVC pipes within
all test pits for future groundwater monitoring.
The appropriate vertical setbacks from base of stormwater disposal facility to seasonal
high groundwater should be maintained. We recommend groundwater monitoring be
accomplished, to assist stormwater disposal design, within installed PVC pipes during
seasonal snow melt and irrigation season (March to October) to confirm groundwater
depths. ALLWEST is currently contracted to perform groundwater monitoring on a
monthly basis. We will monitor groundwater levels until we are instructed to cease
monitoring.
7.12 Asphalt Pavement
Prior to pavement section construction, the subgrade should be prepared as
recommended in section 7.3 Site Preparation. Local and collector roadways should be
designed for a 20 -year Equivalent Single Axle Load (ESAL) of 33,000 and 120,000,
respectively, which is equivalent to a traffic index (TI) of 6 and 7, respectively. If actual
traffic conditions are different than what is stated, we should be notified so that we may
modify our pavement section design.
The following flexible asphalt pavement section design is provided based on the Idaho
Transportation Department (ITD) design methodology, utilizing Ada County Highway
District (ACHD) substitution ratios. Majority of the site roadway subgrade will consist of
lean clay soil, and therefore an assumed R -value of 5 should be utilized for pavement
section design. Based on this assumption, we recommend the following pavement
sections be utilized for subdivision roadway construction for local and collector roadways.
The following table presents these pavement sections.
Base course and subbase should conform to the material recommendations as noted
in this report, and should be placed over a properly prepared subgrade. The subgrade,
subbase, and base course surfaces should slope at no less than 2 percent away from
the crown of the roadway to help reduce the potential for surface water infiltration into
the underlying pavement subgrade.
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Asphalt
Aggregate
Granular
Pavement Application
Concrete
Base Course
Subbase
(inches)
(inches)
(inches)
Local Roadway
2.5
4
13
Collector Roadway
3
6
13
Base course and subbase should conform to the material recommendations as noted
in this report, and should be placed over a properly prepared subgrade. The subgrade,
subbase, and base course surfaces should slope at no less than 2 percent away from
the crown of the roadway to help reduce the potential for surface water infiltration into
the underlying pavement subgrade.
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Asphalt concrete pavement should be compacted to minimum of 92 percent of the Rice
density. Crack maintenance on pavements should be performed at a minimum of every
3 years, or when cracking is evident. Crack sealing will help reduce surface water
infiltration into the supporting soils.
8.0 ADDITIONAL RECOMMENDED SERVICES
To maintain continuity and efficiency, we recommend ALLWEST be retained to provide
observations and testing throughout construction. As an independent testing
laboratory, ALLWEST can document the recommendations included in this report are
properly implemented, provide quality control testing and observe earthwork for
conformance to project specifications. As a minimum, we recommend the following
testing and observations be provided by ALLWEST:
• Observe removal of vegetation, topsoil, tree roots, fill, and any other unsuitable
soils.
• Observe proof -rolling of subgrade prior to placement of fill or construction
materials.
• Observe removal of disturbed soil and subgrade stabilization, if required.
• Conduct compaction testing of fill placed for site grading, utilities, and pavement
areas.
• Observe stormwater disposal facility subgrades for depths and receiving soils,
as well as observe separation/filter fabric installation.
• Observe placement of and test asphalt for compaction, oil content and
gradation.
If we are not retained to provide the recommended construction observation and
testing services, we cannot be responsible for soil engineering related construction
errors or omissions.
9.0 EVALUATION LIMITATIONS
This report has been prepared to assist the planning, design and construction of the
proposed Sky Mesa Commons Subdivision located in Meridian, Idaho. Our services
consist of professional opinions and conclusions made in accordance with generally
accepted geotechnical engineering principles and practices in our local area at the time
this report was prepared. This acknowledgement is in lieu of all warranties either
expressed or implied.
The following plates complete this report:
Appendix A — Site Vicinity Map, Exploration Location Plan
Appendix B — Test Pit Logs, Unified Soil Classification System
Appendix C — Laboratory Test Results
Construction Materials Testing & Special Inspection
Geotechnical Engineering
ALLWEBT Testing &Engineering Environmental Consulting
Non -Destructive Testing
Welder Certification
Appendix A
Site Vicinity Map
Exploration Location Plan
ALLWEST
Testing & Engineering
E. TACONIC DRIVE
XP -3
Legend
E] Approximate location of test pit observed by ALLWEST.
Note: Slotted PVC pipes installed in all test pits observed.
F
Figure A-2 — Exploration Location Plan
^LLWEST Geotechnical Evaluation
Testing & Engineering Sky Mesa Commons
Meridian, Idaho
255 N. Linder Road, Suite 100 Client Name: Woodside Harris, LLC
Meridian, Idaho 83642 Project No.: 517-69OG
Phone: 208-895-7898 Fax: 208-898-3959 Date: January 2018
L I
XP -3
Legend
E] Approximate location of test pit observed by ALLWEST.
Note: Slotted PVC pipes installed in all test pits observed.
F
Figure A-2 — Exploration Location Plan
^LLWEST Geotechnical Evaluation
Testing & Engineering Sky Mesa Commons
Meridian, Idaho
255 N. Linder Road, Suite 100 Client Name: Woodside Harris, LLC
Meridian, Idaho 83642 Project No.: 517-69OG
Phone: 208-895-7898 Fax: 208-898-3959 Date: January 2018
Test Pit Logs
Unified Soil Classification System (USCS)
DATE STARTED: 12/19/2017
TEST PIT 1
ALLWEST TESTING & ENGINEERING, INC.
DATE FINISHED: 12/19/2017
EXCAVATOR: CASE 580C
MERIDIAN, IDAHO
OPERATOR: Steve Just
EXCAVATION METHOD: 3 -ft wide bucket
GEOTECHNICAL SECTION
COMPANY: Just Dig'It Exc.
LOGGER: Isaac Rede
TEST PIT LOG
WEATHER: Cloudy, Cold
PROJECT: 517-69OG
NOTES: See Figure A-2 in Appendix A for approximate test pit location.
Sky Mesa Commons
LATITUDE (DEGREES): N 43°33'11.3292" (43.553147°)
O
W
LONGITUDE (DEGREES): W -116°21'33.6924" (-116.359359°)
W
TOTAL DEPTH: 9'
a
i
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<
NOTES
DESCRIPTION
Lean CLAY with sand; brown, very stiff to hard, moist
Moderate roots and vegetation observed from
0 to 3 inches
Pocket penetrometer = 3.5 to 4.5 tsf
BG
Passing No. 200 sieve = 80%
1
Moisture content = 25.4%
Atterberg limits: LL = 36, PL = 18, PI = 18
2
Sandy SILT; tan, medium dense, moist
BG
Passing No. 200 sieve = 50%
Moisture content = 26.7%
3—
.....calcium carbonate to weak cementation observed from 2 to 5
..... calcium
feet
4-
5—
5Poorly-graded
Poorly-graded SAND with gravel; tan, medium dense, moist to
saturated
6-
7 -
d
U)
8-
9—
Test pit terminated at 9 feet due to caving conditions.
Slotted PVC pipe installed to 9 feet.
10--
1 T-
1 2-
13-
1
-T5-
WATER LEVELS
7'
-V WHILE EXCAVATING
3 AT COMPLETION
Sheet 1 of 1
Y AFTER EXCAVATING
ALLWEST TESTING & ENGINEERING, INC.
DATE STARTED: 12/19/2017
TEST PIT 2
EXCAVATOR: CASE 580C
DATE FINISHED: 12/19/2017
MERIDIAN, IDAHO
OPERATOR: Steve Just
EXCAVATION METHOD: 3 -ft wide bucket
GEOTECHNICAL SECTION
COMPANY: Just Dig'It Exc.
LOGGER: Isaac Rede
TEST PIT LOG
WEATHER: Cloudy, Cold
PROJECT: 517-69OG
NOTES: See Figure A-2 in Appendix A for approximate test pit location.
Sky Mesa Commons
$
LATITUDE (DEGREES): N 43°33'10.8756" (43.553021°)
O
a
LONGITUDE (DEGREES): W-116'21'26.4528" (-116.357348°)
W
j
TOTAL DEPTH: 9.5'
a
a
X
<
NOTES
DESCRIPTION
Lean CLAY with sand; brown, very stiff to hard, moist
Moderate roots and vegetation observed from
0 to 3 inches
Pocket penetrometer = 3.5 to 4.5 tsf
J
U
1
Sandy SILT; tan, medium dense, moist
2—
.....calcium carbonate observed from 1-3/4 to 5 feet
..... calcium
4-
5—
5.....moderate
..... moderate cementation observed from 5 to 6 feet
6—
Poorly-graded SAND with gravel; tan, medium dense, moist to
saturated
7
a
8 _
9
Test pit terminated at 9-1/2 feet due to caving conditions.
Slotted PVC pipe installed to 9-1/2 feet.
10-
1
12-
13-
11
12f-
-T5'—
WATER LEVELS
8'
SZ WHILE EXCAVATING
Y AT COMPLETION
Sheet1 of 1
7 AFTER EXCAVATING
ALLWEST TESTING & ENGINEERING, INC.
DATE STARTED: 12/19/2017
TEST PIT 3
EXCAVATOR: CASE 580C
DATE FINISHED: 12/19/2017
MERIDIAN, IDAHO
OPERATOR: Steve Just
EXCAVATION METHOD: 3 -ft wide bucket
GEOTECHNICAL SECTION
COMPANY: Just Dig'lt Exc.
LOGGER: Isaac Rede
TEST PIT LOG
WEATHER: Cloudy, Cold
PROJECT: 517-69OG
NOTES: See Figure A-2 in Appendix A for approximate test pit location.
Sky Mesa Commons
LATITUDE (DEGREES): N 43°33'7.9956" (43.552221 °)
O
aw.
LONGITUDE (DEGREES): W-116'21'28.4832" (-116.357912°)
U
wUj
=
TOTAL DEPTH: 9.5'
aJ
W
<
NOTES
DESCRIPTION
Lean CLAY with sand; brown, very stiff, moist
Moderate roots and vegetation observed from
0 to 3 inches
Pocket penetrometer = 2.5 to 3.5 tsf
1
�
2
Sandy SILT; tan, medium dense, moist
3
.....calcium carbonate observed from 2 to 4 feet
_j
4
.....moderate cementation observed from 4 to 4-1/2 feet
Poorly -graded SAND with gravel; tan, medium dense, moist to
saturated
5
8
7
a
u)
8 -
-
9
Test pit terminated at 9-1/2 feet due to caving conditions.
Slotted PVC pipe installed to 9-1/2 feet.
1
1
1
19-
1
WATER LEVELS
8'
-V WHILE EXCAVATING
3 AT COMPLETION
Sheet 1 of 1
t AFTER EXCAVATING
ALLWEST TESTING & ENGINEERING, INC.
DATE STARTED: 12/19/2017
TEST PIT 4
EXCAVATOR: CASE 580C
DATE FINISHED: 12/19/2017
MERIDIAN, IDAHO
OPERATOR: Steve Just
EXCAVATION METHOD: 3 -ft wide bucket
GEOTECHNICAL SECTION
COMPANY: Just Dig'It Exc.
LOGGER: Isaac Rede
TEST PIT LOG
WEATHER: Cloudy, Cold
PROJECT: 517-69OG
NOTES: See Figure A-2 in Appendix A for approximate test pit location.
Sky Mesa Commons
LATITUDE (DEGREES): N 43°33'6.768" (43.55188°)
O
LU
IL
LONGITUDE (DEGREES): W-116'21'33.9084" (-116.359419°)
U
IL
TOTAL DEPTH: 13'
a
IL
NOTES
DESCRIPTION
Lean CLAY with sand; brown, very stiff, moist
Moderate roots and vegetation observed from
0 to 3 inches
Pocket penetrometer = 2.5 to 3.5 tsf
1
U
Sandy SILT; tan, medium dense, moist
2
3-
4-
45678
5-
6-
7-
8--
Poorly -graded SAND with gravel; tan, medium dense, moist to
saturated
Field seepage test performed at 9 feet.
9
Field seepage rate = > 30 in/hr
1
CL
U
1
1
1
Test pit terminated at 13 feet.
Slotted PVC pipe installed to 13 feet.
1
WATER LEVELS
0.75'
V WHILE EXCAVATING
3 AT COMPLETION
Sheet 1 of 1
M AFTER EXCAVATING
ALLWEST TESTING & ENGINEERING, INC.
DATE STARTED: 12/19/2017
TEST PIT 5
EXCAVATOR: CASE 580C
DATE FINISHED: 12/19/2017
MERIDIAN, IDAHO
OPERATOR: Steve Just
EXCAVATION METHOD: 3 -ft wide bucket
GEOTECHNICAL SECTION
COMPANY: Just Dig'It Exc.
LOGGER: Isaac Rede
TEST PIT LOG
WEATHER: Cloudy, Cold
PROJECT: 517-69OG
NOTES: See Figure A-2 in Appendix A for approximate test pit location.
Sky Mesa Commons
$
LATITUDE (DEGREES): N 43°33'4.5108" (43.551253°)
O
a
LONGITUDE (DEGREES): W-116'21'33.9696" (-116.359436°)
U
TOTAL DEPTH: 13'
a
a
<
NOTES
DESCRIPTION
Lean CLAY with sand; brown, very stiff to hard, moist
Moderate roots and vegetation observed from
0 to 3 inches
1
U
BG
Passing No. 200 sieve = 71 %
Moisture content = 23.7%
Atterberg limits: LL = 40, PL = 13, PI = 27
2
Sandy SILT; tan, medium dense, moist
3
BG
Passing No. 200 sieve = 55%
Moisture content = 29.7%
.....calcium carbonate to weak cementation observed from 2-1/2
4
to 5 feet
J
5-
6—
.....moderate cementation observed from 5 to 7 feet
7
Poorly -graded SAND with gravel; tan, medium dense, moist
8
9—
1
a.
�
1
1
13—
Test pit terminated at 13 feet.
Slotted PVC pipe installed to 13 feet.
1
WATER LEVELS
SZ WHILE EXCAVATING
Q AT COMPLETION
Sheet 1 of 1
L AFTER EXCAVATING
DATE STARTED: 12/19/2017
TEST PIT 6
ALLWEST TESTING & ENGINEERING, INC.
DATE FINISHED: 12/19/2017
EXCAVATOR: CASE 580C
MERIDIAN, IDAHO
OPERATOR: Steve Just
EXCAVATION METHOD: 3-ft wide bucket
GEOTECHNICAL SECTION
COMPANY: Just Di g` It Exc.
LOGGER: Isaac Rede
TEST PIT LOG
WEATHER: Cloudy, Cold
PROJECT: 517-69OG
NOTES: See Figure A-2 in Appendix Afor approximate test pit location.
Sky Mesa Commons
LATITUDE (DEGREES): N 43033'3.9744" (43.551104°)O
a
LONGITUDE (DEGREES): W -116°21'25.02" (-116.35695°)
U
W
U)
TOTAL DEPTH: 10'
a
a
<
NOTES
DESCRIPTION
Lean CLAY with sand; brown, stiff to very stiff, moist
Moderate roots and vegetation observed from
0 to 3 inches
Pocket penetrometer = 1.5 to 3 tsf
1
BLK
2-
3
Sandy SILT; tan, medium dense, moist
.....calcium carbonate observed from 3 to 4 feet
4—
Poorly-graded SAND with gravel; tan, medium dense, moist to
saturated
5-
6-
67
7—
U)
U)
8 -
-
9
10--
Test pit terminated at 10 feet due to caving conditions.
Slotted PVC pipe installed to 10 feet.
1
1
1
1
WATER LEVELS
8'
Q WHILE EXCAVATING
Z AT COMPLETION
Sheet 1 of 1
7 AFTER EXCAVATING
Unified Soil Classification System
MAJOR DIVISIONS
SYMBOL
TYPICAL NAMES
Well -Graded Gravel,
CLEAN
GW
Gravel -Sand Mixtures.
GP
Poorly -Graded Gravel,
GRAVELS
Gravel -Sand Mixtures.
GRAVELS
Silty Gravel,
GRAVELS
GM
Gravel -Sand -Silt Mixtures.
COARSE
WITH FINES
Clayey Gravel,
GRAINED
GC
Gravel -Sand -Clay Mixtures,
SOILS
Well -Graded Sand,
CLEAN
SW
Gravelly Sand.
SP
Poorly -Graded Sand,
SANDS
Gravelly Sand.
SANDS
Silty Sand,
SANDS
SM
Sand -Silt Mixtures.
SC
Clayey Sand,
WITH FINES
Sand -Clay Mixtures.
Inorganic Silt,
ML
Silty or Clayey Fine Sand.
SILTS AND CLAYS
Inorganic Clay of Low to
CL
Medium Plasticity,
LIQUID LIMIT
Sandy or Silty Clay.
LESS THAN 50%
Organic Silt and Clay of Low
FINE
OL
Plasticity.
GRAINED
Inorganic Silt, Elastic Silt,
SOILS
MH
Micaceous Silt,
SILTS AND CLAYS
Fine Sand or Silt.
Inorganic Clay of High Plasticity,
LIQUID LIMIT
CH
Fat Clay.
GREATER THAN 50%
Organic Clay of Medium to High
OH
Plasticity.
Peat, Muck and Other Highly
Highly Organic Soils
PT
Organic Soils.
ALLWEST
Testing & Engineering
Appendix C
Laboratory Test Results
ALLWEST
Testing & Engineering
Tahle C-1 - Summary of Laboratory Test Results
Test
Pit No.
Depth
(Feet)
Moisture
Content
N
Gradation
Gravel Sand
Silt(
Atterberg Limits
Liquid Plasticity
Limit Index
Sample Classification
USCSClay
( )
1
0.5-1
25.4
20
80
36 18
Lean CLAY with sand CL
1
2.5-3 '
26.7
50
50
Sandy SILT ML
5
1-1.5
23.7
29
71
40 27
Lean CLAY with sand CL
5
3-3.5
29.7
45
55
Sandy SILT ML
Table C-1
255 N. Linder Road, Suite 100 • Meridian, Idaho 83642 • (208) 895-7895 • Fax (208) 898-3959
www.allwesttesting.com
This report may not be reproduced, except in full, without the permission of ALLWEST Testing and Engineering, Inc.
,
i
,
,
,
i
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,
r
,
LIQUID AND PLASTIC LIMITS TEST REPORT
60
,
Dashed line indicates the approximate
,
----- CL -ML
i
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Lipper limit boundary for natural soils
u u
I-1 ®I° r-1
50
40
d
X
Ci W
n
z
W
E U 30
c 1—
W
J
06
d
C
20
W
J
J
10
0
c
0
N
0
P
N 0
0 10 20 30 40 50 60
70 80 90 100 110
z
LIQUID LIMIT
0
MATERIAL DESCRIPTION
LL
PL
PI
%<#40
%<#200
USCS
3 ®
Lean Clay with sand
36
18
18
80%
CL
Lean Clay with sand
40
13
27
--
71%
CL
X
X
N
O
Project No. 517-69OG Client: Woodside Harris, LLC
Remarks:
a)
Project: Sky Mesa Commons
®Location: TP-1 Depth: 0.5-1'
s
■Location: TP-5 Depth: 1-1.5'
tf
0
a
ALLWEST TESTING & ENGINEERING
�
Meridian Idaho
Figure C-1
,
i
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,
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,
'
'
,
,
----- CL -ML
i
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�
u u
I-1 ®I° r-1
Tested By: J. Varozza Checked By: I. Rede