CC - Geotech Report Construction Materials Testing &Special Inspection
ALLWEBT Geotechnical Engineering
Environmental Consulting
Test!i n g & Engineering Non-Destructive Testing
� Welder Certification
March 4, 2019
Randal S. Clarno
Shelburne Properties, LLC
c/o
Jesus Tovar
Criterion Land Management, LLC
7440 East Pinnacle Peak Road, Suite 142
Scottsdale, Arizona 85255
is@criterionland.com
RE: Geotechnical Evaluation
Shelburne South
East Amity Road
Meridian, Idaho
ALLWEST Project No. 519-052G
Mr. Clarno:
ALLWEST Testing & Engineering, Inc. (ALLWEST) has completed the authorized
geotechnical evaluation for the Shelburne South development 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 of 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 Shelburne Properties, LLC. If you have
any questions or need additional information, please do not hesitate to call us at (208)
895-7898.
Sincerely,
ALLWEST Testing & Engin ,
e
,3 9
14253
Adrian Mascorro, P.E. o
Area / Engineering Manager �OF Iov,
N+WA
255 North Linder Road, Ste. 100, Meridian, ID 83642
Phone: (208) 895-7898 + Fax: (208) 898-3959
Hayden, ID . Lewiston, ID • Meridian, ID • Spokane Valley, WA
www.allwesttesting.com
GEOTECHNICAL EVALUATION
SHELBURNE SOUTH
MERIDIAN, IDAHO
ALLWEST PROJECT NO. 519-052G
March 4, 2019
Prepared for:
Randal S. Clarno
Shelburne Properties
c/o
Jesus Tovar
Criterion Land Management, LLC
7440 East Pinnacle Peak Road, Suite 142
Scottsdale, Arizona
Prepared By:
ALLWEST Testing & Engineering, Inc.
255 North Linder Road, Suite 100
Meridian, Idaho 83642
Al LWEST
Testing & Engineering
WWW.ALLWESTTESTING.COM
TABLE OF CONTENTS
ALLWEST Project No. 519-052G
Shelburne South
Meridian, Idaho
Page
1.0 SCOPE OF SERVICES ........................................................................................ 1
2.0 PROJECT UNDERSTANDING.............................................................................2
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 .......................................................................3
5.1 Subsurface Soil Conditions ............................................................................... 3
5.2 Subsurface Water..............................................................................................4
6.0 LABORATORY TESTING ....................................................................................4
7.0 CONCLUSIONS AND RECOMMENDATIONS ....................................................4
7.1 Planning Considerations ...................................................................................4
7.2 Site Grading ...................................................................................................... 5
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
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Geotechnical Evaluation
Shelburne South
Meridian, Idaho
ALLWEST Testing & Engineering, Inc. (ALLWEST) has completed the authorized
geotechnical evaluation for the proposed Shelburne South development located in
Meridian, Idaho. The general location of the site 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 to provide opinions and recommendations with
respect to the proposed construction, relative to earthwork, utility construction,
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) Performed a site visit to observe site accessibility and to pre-mark exploration
locations to assist the utility notification company. Notified Idaho Digline to Pre-
mark underground utilities prior to our exploration.
2) Subcontracted a backhoe and operator to observe the excavation of 9
exploratory test pits on February 6, 2019. 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 a field seepage test within 6 test pits, and installed PVC pipes
within 6 select test pits, for potential 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 519-
052P dated January 15, 2019.
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2.0 PROJECT UNDERSTANDING
Based on our communication with you and review of the Conceptual Layout prepared
by T-O Engineers (dated September 24, 2018), we understand plans consist of an
approximate 19 acres residential development with associated infrastructure,
stormwater disposal facilities, and asphalt-paved roadways. 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.
An existing house residence with associated outbuilding (Williams lot) exists along
the northwest portion of the site. The residence will remain and be a part of the
overall subdivision development. The existing residence and outbuildings located
along the south edge of the site will be demolished as part of the development.
3.0 EVALUATION PROCEDURES
To complete this evaluation, we observed the excavation of 9 total test pits utilizing a
Case 580C excavator with a 3-foot-wide bucket. We obtained select soil samples for
laboratory testing, and installed slotted PVC pipes within select test pits for future
groundwater monitoring. The approximate locations of the test pits are shown on
Figure A-2 — Exploration Location Plan in Appendix A.
4.0 SITE CONDITIONS
At the time of our field exploration, the site was undeveloped and contained surficial
grasses and vegetation. The site sloped down from south to north. Multiple existing
small ditches traversed the site. The site is bordered by undeveloped land to the
west, East Amity Road to the south, undeveloped land to the east, the Tenmile
Feeder Canal to the northeast, and undeveloped land to the north.
4.1 General Geologic Conditions
The geologic conditions at the site are mapped as Gravel of Gowen Terrace
consisting of sandy pebble and cobble gravel, 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 Aquic Torriorthents, Elijah silt loam, and Pipeline silt loam. The parent
materials are mixed alluvium, lacustrine deposits and/or loess, silty alluvium and/or
loess over sandy alluvium.
The soils encountered in the test pits are generally consistent with the NRCS and
geologic mapping.
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5.0 EXPLORATION AND SAMPLING
We observed the excavation of 9 total test pits at the approximate locations shown on
Figure A-2 — Exploration Location Plan. 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 disturbed soil samples from exploration locations. We also
installed slotted PVC pipes within 6 select 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 backfill should be re-excavated and compacted to a minimum of 95 percent of the
maximum dry density as determined by ASTM D 1557 (modified Proctor).
5.1 Subsurface Soil Conditions
The site typically contains 6 inches of surface roots and vegetation. The majority of the
site consists of surficial lean clay soils, overlying silty and sandy soils, which overly
gravel, sand, and silt soils.
Specific descriptions of the soil types observed during our field exploration follow:
Lean clay with sand (native) — At the ground surface, with exception of test pits TP-6
and TP-9, we observed native lean clay with sand to depths of 1'/4 to 3'/2 feet below
existing ground. The lean clay with sand appeared brown, stiff, and moist.
Sandy silt / silt with sand — Underlying lean clay with sand (except TP-2, TP-3, TP-5,
and TP-8), and at the ground surface within test pits TP-6 and TP-9, we observed
sandy silt or silt with sand to depths of 1% to 41/2 feet. The sandy silt and silt with sand
appeared tan, medium dense, and moist.
Poorly-graded sand with silt — Underlying sandy silt, silt with sand or lean clay, we
observed poorly-graded sand with silt to depths of 5 to 10 feet. Sand with silt
appeared brown, medium dense, moist, and select zones contained weak to moderate
calcium carbonate cementation.
Poorly-graded gravel with silt, sand and cobbles —Underlying silt with sand, we
observed poorly-graded gravel with silt, sand and cobbles to depths of 7'/2 to greater
than 13 feet. The gravel soils appeared tan, medium dense, and moist.
Detailed soil descriptions, depths and notes are presented on individual test pit logs in
Appendix B. 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 change
significantly from those observed, construction timing, plans and costs may change.
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5.2 Subsurface Water
At the time of exploration, we did not observe groundwater within test pits.
Groundwater in the area is primarily influenced by local irrigation and the nearby
Tenmile Feeder Canal. However, changes in precipitation, construction, and irrigation
may also impact the depth of groundwater on the site.
5.3 Seepage Testing
We performed field seepage testing within test pits TP-1, TP-2, TP-4, TP-5, TP-6,
and TP-9 at depths of 6 to 10 feet within poorly-graded sand with silt; poorly-graded
gravel with silt, sand and cobbles; and poorly-graded gravel with sand and cobbles.
We measured a field seepage rates of greater than 15 inches per hour (in/hr).
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) and California Bearing Ratio (ASTM D 1883).
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, pavements 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. Test pit locations,
and any other larger excavations, should be surveyed so that they may be located
prior to earthwork construction.
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7.2 Site 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.
7.3 Site Preparation
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 6 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 may 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 section 7.4 Subgrade
Stabilization.
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 6 inches and should be relatively free of sand and fines (silt
and clay). The first layer of cobble should be placed in a 12- to 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, non-disturbed subgrade with smooth surface. Loose/disturbed soil
should be removed prior to placement of geosynthetic reinforcement materials.
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• A minimum weight 4-ounce, non-woven filter fabric should be placed on the
properly prepared subgrade. The geosynthetic reinforcement should be placed
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 to 18 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 once placed, should be statically
rolled. This section is considered the "bridge" section over soft subgrades.
• After the first "bridge" lift has been placed, the remaining fill material above the
"bridge" section should be compacted to structural fill criteria as noted in
section 7.7 Fill Placement & Compaction using vibratory compaction methods.
• Vibrations should be discontinued if it reduces the subgrade stability. If
compaction criteria is not met within the fill lift above the "bridge" section, the
"bridge" section thickness is not sufficient, and subgrade stabilization must be
attempted again with a greater "bridge" section.
The geotechnical engineer or a representative of the geotechnical engineer must 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 and/or soils containing vegetation or debris are only suitable for use in
non-structural landscape areas. Import materials should be granular soil free of
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organics, debris and other deleterious material and meet the following criteria. Import
materials should be approved by ALLWEST prior to delivery to the site.
Fill Type Recommendations
Site Grading, Maximum size <_ 6 inches;Structural Fill Retained on %4 inch Sieve < 30o ;
Liquid limit < 50%
Maximum size <_ 6 inches;
Granular Structural Fill, Retained on 3/4-inch Sieve < 30%;
Subbase Gravel Passing No. 200 Sieve <_ 15%; Non-plastic
Alternatively, meet ISPWC section 801 6 inches
Maximum size <_ 1 inches;
Crushed Base Course Retained on 3/4-inch Sieve < 10%;
Passing No. 200 Sieve < 10%; Non-plastic
Alternatively, meet ISPWC section 802 (Type 1)
Maximum size <_ 2 inches;
Utility Trench Backfill Retained on %-inch Sieve < 30%;
Passing No. 200 Sieve <_ 100 ; 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- to 12-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 Grading / Structural Fill / Pavements 95
Utility Trench Backfill 92
Base Course/ Subbase 95
* Proof-roll should be observed by a representative of the geotechnical engineer.
7.8 Utility Trenches
Support soil for underground utilities will likely consist of lean clay, poorly-graded
sand, or sandy silt soils. 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 Materials. The on-site soils may be difficult
to compact in utility trenches.
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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
Seepage Rate and Soils
During our investigation, we performed field seepage testing within poorly-graded
sand with silt and poorly-graded gravel with silt, sand and cobbles soils, where we
measured field seepage rates of greater than 15 in/hr. We also performed seepage
testing within non-cemented or non-calcium carbonate soils.
Where calcium carbonate cementation is noted on test pit logs (within sand, silt and
gravel soils), we do not recommend stormwater disposal be accomplished within
these calcium carbonate cemented soil layers. As such, stormwater facilities should
be excavated beyond the depth of cementation.
Based on our field seepage testing and observations, we recommend stormwater
disposal occur within non-cemented poorly-graded sand with silt or poorly-graded
gravel with silt, sand and cobbles, which vary in depth throughout the site. Refer to
individual test pit logs to determine depths of un-cemented suitable permeable soils.
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The following allowable design seepage rate may be utilized for stormwater disposal
on-site within non-cemented sandy and gravelly soils:
• Sandy & Gravelly soils (non-cemented)..........................................3 in/hr
Stormwater disposal facilities should be constructed a minimum of 1 foot into non-
cemented sandy or gravelly soils. Seepage beds 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,
and to ensure the separation/filter fabric has been properly installed.
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
370,000, respectively, which is equivalent to a traffic index (TI) of 6 and 8,
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. Based on the CBR test performed, it correlates to an
R-value of 5 for roadway design. We recommend the following pavement sections
based on subsurface conditions observed and local and/or collector roadways for
design.
Asphalt Aggregate Granular
Pavement Application Concrete Base Course Subbase
(inches) (inches) (inches)
Local Roadway 2.5 4 13
Collector Roadway 3 6 17
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.
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.
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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, tree roots, fill, and any other unsuitable soils.
• Observe subgrade proof-rolling prior to fill construction materials placement.
• Observe removal of disturbed soil and subgrade stabilization, if required.
• Conduct compaction testing of fill 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/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
Shelburne South development 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
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Non-Destructive Testing
Welder Certification
Appendix A
Site Vicinity Map
Exploration Location Plan
ALLWEST
Testing & Engineering
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Figure A-2 - Exploration Location Plan
ALLWEST Geotechnical Evaluation
Testing & Engineering Shelburne South
Meridian, Idaho
255 N. Linder Road, Suite 100 Client: Shelburne Properties, LLC
Meridian, Idaho 83642 Project No.: 519-052G
Phone: (208) 895-7898 Fax: (208) 898-3959 Date: March 2019
Appendix B
Test Pit Logs
Unified Soil Classification System (USCS)
ALLWEST
Testing & Engineering
ALLWEST TESTING&ENGINEERING,INC. DATE STARTED: 2/6/2019 TEST PIT 1
DATE FINISHED: 2/6/2019 EXCAVATOR: CASE 580C
MERIDIAN,IDAHO OPERATOR:Steve Just
EXCAVATION METHOD:3-ft wide bucket
GEOTECHNICAL SECTION COMPANY:Just Dig'It Exc.
TEST PIT LOG LOGGER: Sikha Neupane
WEATHER:Sunny
PROJECT:519-052G NOTES:See Figure A-2 in Appendix A for approximate test pit location.
Shelburne South
LATITUDE(DEGREES):N 43°33'40.86" (43.56135°)
= LONGITUDE(DEGREES):W-116°20'21.9408" (-116.339428°) W
F U U �
o j TOTAL DEPTH: 13' o-
0
DESCRIPTION W U) NOTES
Lean CLAY with sand(Native); brown,stiff, moist Significant roots and vegetation observed to 6
inches.
1 Passing No.200 sieve=84%
BG Moisture content=27.4%
Atterberg limits: LL=37,PL= 19, PI =18
J
U
2
3
Sandy SILT;tan,medium dense, moist BG Passing No.200 sieve=59%
Moisture content= 10.6%
4—
Poorly-graded SAND with silt;brown,medium dense, moist
5
d
BG
g Field seepage test performed at 6 feet.
Field seepage rate= 19 in/hr
Poorly-graded SAND with silt and gravel;brown,medium dense,
moist
7
8 d
y
9
Poorly-graded GRAVEL with sand and cobbles;tan,medium
dense,moist °
1 0
O
1 a O
°
0
Q
1 °�
0
Q
°
1 Test pit terminated at 13 feet.
Perforated PVC pipe installed to 13 feet.
1
WATER LEVELS
a WHILE EXCAVATING
Y AT COMPLETION
1 AFTER EXCAVATING Sheet 1 of 1
ALLWEST TESTING&ENGINEERING,INC. DATE STARTED: 2/6/2019 TEST PIT 2
DATE FINISHED: 2/6/2019 EXCAVATOR: CASE 580C
MERIDIAN,IDAHO OPERATOR:Steve Just
EXCAVATION METHOD:3-ft wide bucket
GEOTECHNICAL SECTION COMPANY:Just Dig'It Exc.
TEST PIT LOG LOGGER: Sikha Neupane
WEATHER:Sunny
PROJECT:519-052G NOTES:See Figure A-2 in Appendix A for approximate test pit location.
Shelburne South
LATITUDE(DEGREES):N 43°33'44.226" (43.562285°)
= LONGITUDE(DEGREES):W-116°20'25.7964" (-116.340499°) W
F U U �
o j TOTAL DEPTH: 12' o-
0
DESCRIPTION W U) NOTES
Lean CLAY with sand(Native); brown,stiff, moist Significant roots and vegetation observed to 6
inches.
1 v
2 Poorly-graded SAND with silt;tan with white mottling,dense,
moist,weak to moderate cementation
gG Passing No.200 sieve= 11%
Moisture content= 13.3%
3
4
d
5
6
7
Poorly-graded GRAVEL with silt,sand and cobbles;tan,medium
dense,moist °
8 o Field seepage test performed at 8 feet.
Field seepage rate=>20 in/hr
0
� O
9IQ
d °
0
1 0
0
°
1 Poorly-graded GRAVEL with sand and cobbles;tan,medium
a dense,moist °
� o
Q
1 Test pit terminated at 12 feet.
Perforated PVC pipe installed to 12 feet.
1
1
WATER LEVELS
a WHILE EXCAVATING
Y AT COMPLETION
1 AFTER EXCAVATING Sheet 1 of 1
ALLWEST TESTING&ENGINEERING,INC. DATE STARTED: 2/6/2019 TEST PIT 3
DATE FINISHED: 2/6/2019 EXCAVATOR: CASE 580C
MERIDIAN,IDAHO OPERATOR:Steve Just
EXCAVATION METHOD:3-ft wide bucket
GEOTECHNICAL SECTION COMPANY:Just Dig'It Exc.
TEST PIT LOG LOGGER: Sikha Neupane
WEATHER:Sunny
PROJECT:519-052G NOTES:See Figure A-2 in Appendix A for approximate test pit location.
Shelburne South
LATITUDE(DEGREES):N 43°33'46.8432" (43.563012°)
= LONGITUDE(DEGREES):W-116°20'23.7984" (-116.339944°) W
F U U �
o j TOTAL DEPTH: 12' o-
0
DESCRIPTION W U) NOTES
Lean CLAY with sand(Native); brown,stiff, moist Significant roots and vegetation observed to 6
inches.
J
U
1
Poorly-graded GRAVEL with silt,sand and cobbles;tan,very
2 dense,moist,weak to moderate cementation °
0
3
DG
4 °
0
c�
IL °
c�
0
5 ....end of cementation at 5 feet
0
6 °
0
°
O
7
°
Silty SAND with gravel; brown,medium dense, moist,induration
8
BG Passing No.200 sieve=33%
Moisture content= 13.2%
9
y
1
1 Sandy SILT; brown,dense, moist
BG Passing No.200 sieve=56%
Moisture content=25%
1 Test pit terminated at 12 feet.
WATER LEVELS
a WHILE EXCAVATING
Y AT COMPLETION
T AFTER EXCAVATING Sheet 1 of 1
ALLWEST TESTING&ENGINEERING,INC. DATE STARTED: 2/6/2019 TEST PIT 4
DATE FINISHED: 2/6/2019 EXCAVATOR: CASE 580C
MERIDIAN,IDAHO OPERATOR:Steve Just
EXCAVATION METHOD:3-ft wide bucket
GEOTECHNICAL SECTION COMPANY:Just Dig'It Exc.
TEST PIT LOG LOGGER: Sikha Neupane
WEATHER:Sunny
PROJECT:519-052G NOTES:See Figure A-2 in Appendix A for approximate test pit location.
Shelburne South
LATITUDE(DEGREES):N 43°33'49.6764" (43.563799°)
= LONGITUDE(DEGREES):W-116°20'26.124" (-116.34059°) W
F U U �
o j TOTAL DEPTH: 13' o-
0
DESCRIPTION W U) NOTES
Lean CLAY with sand(Native); brown,stiff, moist Significant roots and vegetation observed to 6
inches.
J
1 L) Passing No.200 sieve=79%
RG/BK Moisture content=26.4%
Atterberg limits: LL=35,PL= 19, PI =16
Sandy SILT;tan,medium dense, moist CBR=5.0
2
BG
Poorly-graded SAND with silt;tan,dense,moist,weak to
3 moderate cementation
4 ai
5 Poorly-graded GRAVEL with silt,sand and cobbles;tan,dense,
moist,weak to moderate cementation
0
6 ....end of cementation at 6 feet °
0
Field seepage test performed at 6-1/2 feet.
° Field seepage rate=>20 in/hr
7 0
c?
a o
C9
O
8
0
O
9 °
0
0
1 Silty SAND with gravel;tan,dense, moist,induration
1
y
1
1 Test pit terminated at 13 feet.
Perforated PVC pipe installed to 13 feet.
1
WATER LEVELS
a WHILE EXCAVATING
Y AT COMPLETION
1 AFTER EXCAVATING Sheet 1 of 1
ALLWEST TESTING&ENGINEERING,INC. DATE STARTED: 2/6/2019 TEST PIT 5
DATE FINISHED: 2/6/2019 EXCAVATOR: CASE 580C
MERIDIAN,IDAHO OPERATOR:Steve Just
EXCAVATION METHOD:3-ft wide bucket
GEOTECHNICAL SECTION COMPANY:Just Dig'It Exc.
TEST PIT LOG LOGGER: Sikha Neupane
WEATHER:Sunny
PROJECT:519-052G NOTES:See Figure A-2 in Appendix A for approximate test pit location.
Shelburne South
LATITUDE(DEGREES):N 43°33'52.7616" (43.564656°)
= LONGITUDE(DEGREES):W-116°20'28.8888" (-116.341358°) W
F U U �
o j TOTAL DEPTH: 10.5' o-
0
DESCRIPTION W U) NOTES
Lean CLAY with sand(Native); brown to tan,stiff, moist Significant roots and vegetation observed to 6
inches.
1
J
U
BG
2—
Poorly-graded SAND with silt;tan,dense,moist,weak to
3 moderate cementation
4-
5-
6-
7—
Poorly-graded GRAVEL with silt,sand and cobbles;tan,dense,
moist,weak to moderate cementation °
8 ...end of cementation at 8 feet o
c�
IL
°
O
9 Poorly-graded GRAVEL with sand and cobbles;tan,dense,moist
0
Q
1 ° Field seepage test performed at 10 feet.
o Field seepage rate=>30 in/hr
Test pit terminated at 10-1/2 feet.
1
1
1
1
WATER LEVELS
a WHILE EXCAVATING
Y AT COMPLETION
1 AFTER EXCAVATING Sheet 1 of 1
ALLWEST TESTING&ENGINEERING,INC. DATE STARTED: 2/6/2019 TEST PIT 6
DATE FINISHED: 2/6/2019 EXCAVATOR: CASE 580C
MERIDIAN,IDAHO OPERATOR:Steve Just
EXCAVATION METHOD:3-ft wide bucket
GEOTECHNICAL SECTION COMPANY:Just Dig'It Exc.
TEST PIT LOG LOGGER: Sikha Neupane
WEATHER:Sunny
PROJECT:519-052G NOTES:See Figure A-2 in Appendix A for approximate test pit location.
Shelburne South
LATITUDE(DEGREES):N 43°33'47.826" (43.563285°)
= LONGITUDE(DEGREES):W-116°20'31.038" (-116.341955°) W
F U U �
o j TOTAL DEPTH: 13' o-
0
DESCRIPTION W U) NOTES
SILT with sand(Native);tan to brown,medium dense,moist Significant roots and vegetation observed to 12
inches.
1
BG
2—
Poorly-graded SAND with silt;tan,dense,moist
3-
4-
5-
6— T
IL
y
Field seepage test performed at 6-1/2 feet.
Field seepage rate=21 in/hr
7
8
9
1 Silty SAND with gravel;tan,dense, moist,induration
1
y
1
1 Test pit terminated at 13 feet.
Perforated PVC pipe installed to 13 feet.
1
WATER LEVELS
a WHILE EXCAVATING
Y AT COMPLETION
1 AFTER EXCAVATING Sheet 1 of 1
ALLWEST TESTING&ENGINEERING,INC. DATE STARTED: 2/6/2019 TEST PIT 7
DATE FINISHED: 2/6/2019 EXCAVATOR: CASE 580C
MERIDIAN,IDAHO OPERATOR:Steve Just
EXCAVATION METHOD:3-ft wide bucket
GEOTECHNICAL SECTION COMPANY:Just Dig'It Exc.
TEST PIT LOG LOGGER: Sikha Neupane
WEATHER:Sunny
PROJECT:519-052G NOTES:See Figure A-2 in Appendix A for approximate test pit location.
Shelburne South
LATITUDE(DEGREES):N 43°33'44.8128" (43.562448°)
= LONGITUDE(DEGREES):W-116°20'28.8528" (-116.341348°) W
F U U �
o j TOTAL DEPTH: 13' o-
0
DESCRIPTION W U) NOTES
Lean CLAY with sand(Native); brown,stiff, moist Significant roots and vegetation observed to 6
inches.
U
1
Sandy SILT;tan to brown,medium dense, moist
2 Poorly-graded SAND with silt;brown,medium dense, moist,
weak to moderate cementation
BG
3
4
d
y
5
6
7 Poorly-graded SAND with silt and gravel;brown,medium dense,
moist,weak to moderate cementation
8-
9—
Poorly-graded GRAVEL with silt and sand;tan,dense,moist
0
1 0
DG
0
IQ
1
d 0
DG
1 0
DG
0
1 Test pit terminated at 13 feet.
Perforated PVC pipe installed to 13 feet.
1
WATER LEVELS
a WHILE EXCAVATING
Y AT COMPLETION
1 AFTER EXCAVATING Sheet 1 of 1
ALLWEST TESTING&ENGINEERING,INC. DATE STARTED: 2/6/2019 TEST PIT 8
DATE FINISHED: 2/6/2019 EXCAVATOR: CASE 580C
MERIDIAN,IDAHO OPERATOR:Steve Just
EXCAVATION METHOD:3-ft wide bucket
GEOTECHNICAL SECTION COMPANY:Just Dig'It Exc.
TEST PIT LOG LOGGER: Sikha Neupane
WEATHER:Sunny
PROJECT:519-052G NOTES:See Figure A-2 in Appendix A for approximate test pit location.
Shelburne South
LATITUDE(DEGREES):N 43°33'42.2892" (43.561747°)
= LONGITUDE(DEGREES):W-116°20'27.1176" (-116.340866°) W
F U U �
o j TOTAL DEPTH: 10.5' o-
0
DESCRIPTION W U) NOTES
Lean CLAY with sand(Native); brown,stiff, moist Significant roots and vegetation observed to 6
inches.
BG
1
Poorly-graded SAND with silt;brown,medium dense, moist,
weak to moderate cementation
2-
3-
4-
5
6-
7—
Poorly-graded SAND with silt and gravel;tan, medium dense,
y
moist
d
y
9 Poorly-graded GRAVEL with silt,sand and cobbles;tan to brown,
dense,moist
c? o
a.
1 � °
0
Test pit terminated at 10-1/2 feet.
1
1
1
1
WATER LEVELS
a WHILE EXCAVATING
Y AT COMPLETION
1 AFTER EXCAVATING Sheet 1 of 1
ALLWEST TESTING&ENGINEERING,INC. DATE STARTED: 2/6/2019 TEST PIT 9
DATE FINISHED: 2/6/2019 EXCAVATOR: CASE 580C
MERIDIAN,IDAHO OPERATOR:Steve Just
EXCAVATION METHOD:3-ft wide bucket
GEOTECHNICAL SECTION COMPANY:Just Dig'It Exc.
TEST PIT LOG LOGGER: Sikha Neupane
WEATHER:Sunny
PROJECT:519-052G NOTES:See Figure A-2 in Appendix A for approximate test pit location.
Shelburne South
LATITUDE(DEGREES):N 43°33'40.9428" (43.561373°)
= LONGITUDE(DEGREES):W-116°20'31.0452" (-116.341957°) W
F U U �
o j TOTAL DEPTH: 10' o-
0
DESCRIPTION W U) NOTES
SILT with sand(Native);tan, medium dense, moist Significant roots and vegetation observed to 6
inches.
1
BG
Poorly-graded SAND with silt;brown,medium dense, moist,
2 weak to moderate cementation
3
4-
5-
6—
All
Poorly-graded GRAVEL with silt,sand and cobbles;tan,dense,
moist
� o
C9
g a ° Field seepage test performed at 8 feet.
0
Field seepage rate=>20 in/hr
0
9 Poorly-graded GRAVEL with sand and cobbles;tan to brown,
dense,moist °
0
a. Q
1
0
Test pit terminated at 10-1/2 feet.
Perforated PVC pipe installed to 10-1/2 feet.
1
1
1
1
—75 WATER LEVELS
a WHILE EXCAVATING
Y AT COMPLETION
T AFTER EXCAVATING Sheet 1 of 1
Unified Soil Classification System
MAJOR DIVISIONS SYMBOL I TYPICAL NAMES
Well-Graded Gravel,
CLEAN GW Gravel-Sand Mixtures.
GRAVELS GP Poorly-Graded Gravel,
GRAVELS Gravel-Sand Mixtures.
Silty Gravel,
COARSE GRAVELS GM Gravel-Sand-Silt Mixtures.
GRAINED WITH FINES GC Clayey Gravel,
SOILS Gravel-Sand-Clay Mixtures.
Well-Graded Sand,
CLEAN SW Gravelly Sand.
SANDS SP Poorly-Graded Sand,
SANDS Gravelly Sand.
Silty Sand,
SANDS SM Sand-Silt Mixtures.
WITH FINES Sc Clayey Sand,
Sand-Clay Mixtures.
ML Inorganic Silt,
SILTS AND CLAYS Silt or Clayey Fine Sand.
Inorganic Clay of Low to
LIQUID LIMIT CL Medium Plasticity,
LESS THAN 50% Sandy or Silty Clay.
FINE OL Organic Silt and Clay of Low
GRAINED Plasticity.
SOILS Inorganic Silt, Elastic Silt,
SILTS AND CLAYS MH Micaceous Silt,
Fine Sand or Silt.
LIQUID LIMIT CH Inorganic Clay of High Plasticity,
GREATER THAN 50% Fat Clay.
OH Organic Clay of Medium to High
Plasticity.
Highly Organic Soils PT Peat, Muck and Other Highly
Organic Soils.
ALLWEST
Testing & Engineering
Appendix C
Laboratory Test Results
ALLWEST
Testing & Engineering
Table C-1: Summary of Laboratory Test Results
Moisture Gradation Atterberg Limits
Test Depth Content Liquid Plasticity CBR Sample Classification
Pit No. (Feet) N Gravel Sand Silt/Clay Limit Index (USCS)
N M) N M M)
1 1 - 1.5 27.4 16 84 37 18 Lean CLAY with sand CL
1 3.5-4 10.6 41 59 Sandy SILT (ML)
2 2.5 - 3 13.3 89 11 Poorly-graded SAND with silt SP-SM
3 8.5- 9 13.2 67 33 Silty SAND (SM)
3 11.5 - 12 25.0 44 56 Sandy SILT (ML)
4 1 - 1.5 26.4 21 79 35 16 5.0 Lean CLAY with sand (CL)
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.
LIQUID AND PLASTIC LIMITS TEST REPORT
60
Dashed line indicates the approximate
upper limit boundary for natural soils
50
�0
' G
40
U
C �
X
W
N- Z_
'
v 30
c F-
LU C/) '
Q i
J /
a: 20
H Off/
H
W
,
J /
J
Q 10
0 ;
c
L-ML ML or OL MH or OH
0
0 10 20 30 40 50 60 70 80 90 100 110
LIQUID LIMIT
0 MATERIAL DESCRIPTION LL PL PI %<#40 %<#200 USCS
• Lean Clay with sand 37 19 18 84% CL
c■ Lean Clay with sand 35 19 16 79% CL
CD
U
X
U
U
U
7
O
` Project No. 519-052G Client: Shelburne Properties,LLC Remarks:
aD Project: Shelburne South
c *Location: TP-1 Depth: 1-1.5'
■Location: TP-4 Depth: 1-1.5'
0
a ALLWEST TESTING & ENGINEERING
D
Meridian Idaho Figure C-1
Tested By: J.Varozza Checked By: S. Neupane
California Bearing Ratio
ASTM D 1883
Project: Shelburne South Project No.: 519-052G
Client: Shelburne Properties, LLC Location: TP-4 @ 1-2 ft
Date Tested: 2/25/2019 Compaction Method: ASTM D1557
Tested By: J. Varozza / C. Downes Classification: Lean Clay with sand (CL)
100
90
80
70
Q- 60
c
0
a 50 PSI @ 0.1 inch penetration= 50
c
0
L 40
30
20
10
0
0 0.1 0.2 0.3 0.4 0.5
Penetration(inches)
CBR @ 0.1 Inch Penetration: 5.0 Maximum Dry Unit Weight(pcf): 109
Swell (%): 3.3 Optimum Water Content (%): 14.1
Dry Unit Weight Before Soak(pcf): 98.8 Remold of Max. Dry Unt Wgt (%): 91
Water Content Before Soak(%): 15.3
Water Content After Soak, Top 1 Inch (%): 31.3
Surcharge (psf): 75
Immersion Period (hrs): 96
Reviewed By: Isaac Rede
Figure: C-2
►LLIET
Testing & Engineering
255 N Linder Rd,Suite 100•Meridian,ID 83642•(208)895-7898•Fax(208)898-3959
www.allwesttesting.com
This report shall not be reproduced except in full without the permission of ALLW EST Testing Engineering, Inc.