HomeMy WebLinkAboutStudies APPLICANT 10/15/2020Earth
Engineers,
Inc.
August 24, 2020
North Lake Property Management
Attn: Zack Reeves
36697 Goats Road
Springfield, Oregon 97478
4660 Main Street, Suite 100 • Springfield • OR 97478
Phone: 541.393.6340 • Fax 541.393.6385
Subject: Geotechnical Investigation Report
New Storage Facility
4155 E Street
Springfield, Oregon 97478
EEI Project No. 20-106-1
Dear Mr. Reeves:
www.earth-engineers.com
(P): 541.729.0045
Email: zrev80Oamail.com
Earth Engineers, Inc. (EEI) is pleased to transmit our attached Geotechnical Investigation
Report for the above referenced project. This report includes the results of our field
investigation, an evaluation of geotechnical factors that may influence the proposed
construction, geotechnical recommendations for the proposed structure, general site
development and the results of our water infiltration test.
We appreciate the opportunity to perform this geotechnical study and look forward to continued
participation during the design and construction phases of this project. If you have any
questions pertaining to this report, or if we may be of further service, please contact our office at
541.393.6340.
Sincerely,
Earth Engineers, Inc.
R 4 v-
Raymond V. Aliperti
Branch Manager
Attachment: Geotechnical Investigation Report
Gregg Thibeaux, P.E.
Geotechnical Engineer
Distribution (1 electronic copy):
Addressee
Aaron Broderick—Johnson Broderick Engineering—aarona be.us.com
GEOTECHNICAL INVESTIGATION REPORT
Geotechnical Investigation Report
New Storage Facility
4155 E Street
Springfield, Oregon 97478
EEI Project No. 20-106-1
Prepared for:
North Lake Property Management
Attn: Zack Reeves
36697 Goats Road
Spnngfield, Lane County, Oregon 97478
Prepared by:
Earth Engineers, Inc.
4660 Main Street, Suite 100
Springfield, Oregon 97478
Phone: 541.393.6340
Fax: 541.393.6385
EEI Report No. 20-106-1
August 24, 2020
Earth
Engineers,
Inc.
Prepared by:
Raymond V. Aliperti
Branch Manager
Reviewed by:
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EXPIRES: 06/30/20 Z Z
Greg Thibeaux, P.E.
Geotechnical Engineer
TABLE OF CONTENTS
Page No.
1.0 PROJECT INFORMATION.......................................................................................1
1.1 Project
Authorization.........................................................................................................
1
1.2 Project
and Site Description..............................................................................................
1
1.3 Purpose and Scope of Services........................................................................................
5
2.0 SUBSURFACE CONDITIONS..................................................................................7
2.1 Mapped Geology and Soils...............................................................................................
7
2.2 Subsurface Materials........................................................................................................
8
2.3 Groundwater Information.................................................................................................
10
2.4 Infiltration Test.................................................................................................................
10
2.5 Seismicity.........................................................................................................................
11
3.0 EVALUATION AND FOUNDATION RECOMMENDATIONS.................................14
3.1 Geotechnical Discussion..................................................................................................
14
3.2 General Site Preparation..................................................................................................
14
3.3 Structural Fill....................................................................................................................
15
3.4 Foundation Recommendations........................................................................................
16
3.5 Floor Slab Recommendations..........................................................................................
17
3.6 Pavement Recommendations..........................................................................................
18
4.0 CONSTRUCTION CONSIDERATIONS..................................................................20
4.1 Drainage and Groundwater Considerations.....................................................................
20
4.2 Moisture Sensitive Soils...................................................................................................
20
4.3 Excavations.....................................................................................................................
21
5.0 REPORT LIMITATIONS.........................................................................................22
APPENDICES:
Appendix A - Test Pit Logs
Appendix B - Soil Classification Legend
1.0 PROJECT INFORMATION
1.1 Pro act Authorization
1 of 22
Earth Engineers, Inc. (EEI) has completed a geotechnical investigation report for the proposed
new Storage Facility to be located at 4155 E Street in Springfield, Oregon (reference Figure 1
and 2 below). Our geotechnical services were authorized by Mr. Zack Reeves on July 7, 2020,
by signing EEI Proposal No. 20-P183, dated June 24, 2020.
1.2 Project and Site Description
Our understanding of the project is based on information provided by Mr. Aaron Broderick with
Johnson Broderick Engineering during a meeting on site on June 11, 2020 and in an email
dated June 23, 2020 which contained a site plan entitled: Site Plan, North Lake Property
Management, 4155 E Street, Springfield, OR 97478 and also marked Preliminary Not For
Construction 2020.04.20.
Briefly we understand the project will consist of construction of one single -story storage facility
along the south side of the property with a two-story office building attached on the west end.
The storage facility will be a pole type building measuring 35 feet north/south by 105 feet
east/west constructed on a concrete slab on grade. The office building will be wood -framed
construction and measure 35 feet north/south by 24 feet east/west. The office building will also
have a concrete slab on grade. In addition, future construction will include one single -story pole
type storage facility along the east side of the property measuring 25 feet east/west by 72 feet
north/south (reference Figure 3 below). The remaining portions of the site will be covered with
asphaltic concrete and a proposed rain garden for water infiltration is planned to be constructed
along E Street.
Currently, the subject site is relatively flat and level and is covered with tall grass, weeds and
blackberry bushes along the south property line. In addition, there are a few trees along the east
and west property lines. From elevations interpolated from Google Earth imagery, the subject
property is currently at about 475 feet above mean sea level.
The property is bordered by E Street to the north, the Arc of Lane County commercial building to
the east, a vacant lot to the south and a single family residential structure to the west.
We have not been provided with any maximum foundation loading from the project structural
engineer and have assumed that maximum isolated column loads, wall loads and floor loads will
not exceed 50 kips, 6 kips per linear foot and 250 pounds per square foot, respectively.
Finally, we assume that maximum cuts and fills will be limited to one to two feet, and have
assumed that the development will be constructed in accordance with the provisions of the 2014
Oregon Structural Specialty Code (2014 OSSC).
E Street Storage Facility Earth Engineers, Inc.
EEI Report No. 20.106.1 August 24, 2020
2 o122
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Figure 1: Site Vicinity Map (base map source: USGS Topo Map, httos://viewer.
nationalmao.aov).
E Street Storage Facility Earth Engineers, Inc.
EEI Report No. 20.106.1 August 24, 2020
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site along E Street.
E Street Storage Facility Earth Engineers.. Inc.
EEI Report No. 20-106-1 August 24. 2020
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E Street Storage Facility Earth Engineers, Inc.
EEI Report No. 20-106-1 August 24, 2020
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Figure 3: Site plan showing locations of proposed structures (base source by Johnson
Broderick Engineering entitled: Site Plan, North Lake Property Management, 4155 E Street,
Springfield, OR 97478, marked Preliminary Not for Construction, dated 2020.04.20).
1.3 Purpose and Scope of Services
The purpose of our services was to perform a geotechnical engineering evaluation of the
proposed building and paved areas. In order to provide geotechnical engineering
recommendations for the proposed structure(s), we performed a subsurface investigation on
July 7, 2020. We performed three test pits (TP -1 through TP -3) using a Takeuchi TB070 track
mounted excavator equipped with an 18 -inch -wide, toothed bucket that was supplied by our
client. The test pits were performed to depths of approximately 6 to 8 feet below the ground
surface.
E Street Storage Facility Earth Engineers, Inc.
EEI Report No. 20.106.1 August 24, 2020
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Grab samples were obtained in the test pits for laboratory testing. After completion of the field
investigation, we performed laboratory testing that included moisture content, particle size
analyses, and Atterberg Limits testing.
This report presents the following recommendations based on our subsurface investigation and
results of our laboratory testing:
• A discussion of subsurface conditions encountered including pertinent soil and rock
properties and groundwater conditions.
• 2019 OSSC seismic design criteria.
• Recommendations for the overall suitability of the in-situ soils for use as utility backfill
and structural fill.
• Structural fill requirements, including gradation and compaction.
• Geotechnical related recommendations for foundation design including allowable
bearing capacity, minimum footing dimensions and estimated total and differential static
settlements for perimeter footings and stem wall.
• Geotechnical related recommendations for slab -on -grade.
• Pavement section thickness recommendations for the proposed asphaltic concrete, and
concrete parking/drive areas, based on an assumed CBR value and assumed traffic
loading conditions.
• Wet and dry weather construction recommendations.
• Groundwater considerations.
• Result of our infiltration testing.
• Discussions on geotechnical issues that may impact the project.
E Street Storage Facility Earth Engineers, Inc.
EEI Report No. 20.106.1 August 24, 2020
2.0 SUBSURFACE CONDITIONS
2.1 Maimed Geoloav and Soils
7 of 22
The subject site lies within the Willamette Valley Geomorphic Province, east of the Coast Range
and west of the Cascade Mountains Geomorphic Provinces. The Willamette Valley Province is
regional lowland that extends from just south of Eugene, Oregon to Vancouver, British Columbia.
Wthin Oregon, this narrow alluvial plain is approximately 130 miles long and ranges from
approximately 20 to 40 miles wide (Orr and Orr, 1996). The province is drained by the Willamette
River, the longest north -flowing river in North America. Compressional forces attendant with uplift
of the Cascade and Coast Range Mountain Ranges during the Miocene and Pliocene epochs
(approximately 4 to 20 million years ago) depressed the Wllamette Valley. The bedrock lithology of
the Wllamette Valley in the vicinity of the subject site consists of the late Eocene aged
(approximately 35 million years ago) Eugene Formation, a generally well consolidated to lithified,
tuffaceous near -shore marine sedimentary rock that was gently folded during the geosynclinal
compressional period described above (Yeats at al., 1991).
Prior to deformation, low energy streams and lakes present within the southern Wllamette Valley
during the Pliocene epoch covered the Eugene Formation with fluvial and lacustrine deposits of
silts and clays to various depths. Wth the rapid uplift of the Cascade Mountains in the Pliocene
epoch, steepened stream gradients resulted in increased erosion of the Cascades and rapid
deposition of thick gravel layers that incised the soft fluvial and lacustrine deposits overlying the
Eugene Formation. Locally, fining upward sequences of rhythmite deposits from the Pleistocene
aged (approximately 2.6 million years ago) Missoula Floods are preserved that record up to 30
advance and retreat cycles of Lake Allison (Waitt, 1985), which filled the Wllamette Valley to a
depth of approximately 350 feet with each flooding event (Allen at al., 1986).
According to the Web Soil Survey's Soil Map - Lane County Area, Oregon (httalAvebsoilsurvev.
nres.usda.aov/aooNVebSoilSurvev.asox), the native soils in the vicinity of the project site consist of
the Coburg -Urban land complex and the Oxley -Urban land complex.
The Coburg -Urban land complex covers approximately 98 percent of the site. This material
typically forms stream terrace landforms with 0 to 3 percent slopes. The parent material of the
Coburg -Urban land complex is loamy alluvium over clayey alluvium. These soils typically do not
flood and are moderately well drained, with depth to a restrictive layer of greater than 80 inches
and depth to a water table of 18 to 30 inches. A typical soil profile for the Coburg -Urban land
complex is, from 0 to 18 inches — silty clay loam, from 18 to 53 inches — silty clay and from 53 to 65
inches — fine sandy loam.
The Oxley -Urban land complex covers approximately the southwest 2 percent of the site. This
material typically forms terrace landforms with 0 to 3 percent slopes. The parent material of the
Oxley -Urban land complex is mixed gravelly alluvium. These soils typically do not flood and are
typically somewhat poorly drained, with depth to a restrictive layer of greater than 80 inches and
depth to a water table of 6 to 18 inches. A typical soil profile for the Oxley -Urban land complex is,
E Street Storage Facility Earth Engineers, Inc.
EEI Report No. 20.106.1 August 24, 2020
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from 0 to 17 inches — gravelly silt loam, from 17 to 23 inches — gravelly clay loam, 23 to 41 inches —
very gravelly clay loam and from 41 to 60 inches — extremely gravelly sand loam.
2.2 Subsurface Materials
As mentioned above, the subsurface conditions for the proposed structure were explored with
three test pits (TP -1 through TP -3). The approximate locations of the test pits are shown on the
Test Pit Location Plan (reference Figure 4 below). The terminal depth of test pits TP -1 through
TP -3 was 6 to 8 feet below existing site grades. The test pits were loosely backfilled with the
excavated soils upon completion.
Disturbed "grab" soil samples were obtained during our subsurface exploration. Each sample
was marked and identified by date sampled, project name, project number, test pit number, and
sample depth. The samples were transported to our laboratory for visual identification and
laboratory testing. Samples not altered by laboratory testing will be retained for 90 days from the
date of this report.
Select soil samples were tested in the laboratory to determine material properties for our
evaluation. Laboratory testing was accomplished in general accordance with ASTM procedures.
The testing performed included moisture content tests (ASTM D2216), the amount of material in
the soils finer than the #200 sieve (ASTM D1140), and an Atterberg Limits test (ASTM D4318).
The test results have been included on the Test Pit Logs in Appendix A.
The materials encountered in test pits TP -1 through TP -3 may be divided into four general
strata, as described below:
FILL: The surface material at all three test pits was a mixture of fine-grained soil with some
gravel fill. The fill material extended to depths between 9 and 15 inches below existing grade at
locations of our test pits. The fill material visually appeared to be a mixture of clays and silts with
some rounded gravel and organics including some wood. Based on our observations during the
excavation of the test pits, the fill material was soft and easy to dig with the mini -excavator.
Topsoil: The soil underlying the fill material described above was native, organic rich buried
topsoil layer consisting of silty clay/clayey silt and dark brown to black in color. The material was
generally moist and the organics visually appeared to be from grass, blackberry and tree roots.
up to 1/2 inch diameter in our test pits. Note: in the excavation for our infiltration test a tree root
approximately 3 inches in diameter was observed at approximately 18 inches below the
adjacent grade. The topsoil layer extended to depths ranging from 2 to 2-1/2 feet below existing
site grades at the exploration locations.
Sandy Lean Clay (CL): The soil underlying the topsoil layer classified as sandy lean clay (CL)
according to the Unified Soil Classification System (USCS) and the results of our laboratory
tests. The soil was red -brown in color and based on observed digging effort and pocket
penetrometer test results (unconfined compressive strength) of 1.5 to 2.5 tons per square foot,
E Street Storage Facility Earth Engineers, Inc.
EEI Report No. 20.106.1 August 24, 2020
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the layer varied in consistency from stiff to very stiff at the exploration locations. Based on
laboratory tests, moistures ranged from 26 to 34 percent. The sandy lean clay extended to
depths of 4 to 5 feet below existing site grades at the exploration locations.
Well -Graded Gravel with Silt and Sand: Underlying the sandy lean clay was well -graded
gravel with silt and sand (locally referred to as "bar -run" gravel). The gravels were gray in color,
moist, and based on the digging effort of the mini -excavator, medium dense to dense. The
gravels were typically sub -rounded to rounded and extended to maximum depths explored of 6
to 8 feet below existing site grades at the exploration locations.
The above subsurface description is of a generalized nature to highlight the major subsurface
stratification features and material characteristics. The test pit logs included in Appendix A at the
end of this report should be reviewed for specific information at specific locations. The test pit
logs include sample locations, soil and rock descriptions, stratifications, pocket penetrometer
(unconfined compressive strength) test results, and results of laboratory tests. The stratifications
shown on the logs represent the conditions only at the actual test pit locations. Variations may
occur and should be expected between locations. The stratifications represent the approximate
boundary between subsurface materials. the actual transition may be gradual.
The fill extent was estimated based on an examination of the soil samples, the presence of
foreign materials, field measurements, and the subsurface data. The fill encountered in test pit
TP -1 was approximately 9 inches thick and the fill encountered in test pits TP -2 and TP -3 was
approximately 15 inches thick. however, the explorations performed are not adequate to
accurately identify the full extent of existing fill across the entire subject property. Consequently,
the actual fill extent may be greater than that shown on the exploration logs and discussed
herein.
Photo 4: Test pit TP -1 showing the fill, topsoil, sandy lean clay and
well -graded gravel with silt and sand layers.
E Street Storage Facility Earth Engineers.. Inc.
EEI Report No. 20-106-1 August 24, 2020
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Figure 4: Site plan showing locations of test pits (TP -1 through TP -3) and Infiltration Test (IT -1)
in relation to the proposed structures (base source by Johnson Broderick Engineering entitled:
Site Plan, North Lake Property Management, 4155 E Street, Springfield, OR 97478, marked
Preliminary Not for Construction, dated 2020.04.20).
2.3 Groundwater Information
Static groundwater was not encountered at the time of digging in any of the test pits (TP -1
through TP -3) on July 7, 2020. It should be noted that water seepage should be expected in
subsurface excavations performed during the wet season. In addition, it is possible for the depth
of a groundwater table to vary at some future time depending upon the amount of irrigation on
the surrounding lots, and upon climatic and rainfall conditions.
E Street Storage Facility Earth Engineers, Inc.
EEI Report No. 20.106.1 August 24, 2020
11 of 22
2.4 Soil Infiltration Test Method and Results
On July 9, 10 and 14, 2020 we performed a soil infiltration test on site (IT -1). The test was
performed along the west portion in the general vicinity of where the proposed stormwater
facility will be as directed by our client (reference Figure 4 above). The infiltration test was
performed at a depth of 4 feet below existing site grades and was performed in the native, well -
graded gravel with silt and sand ('bar -run" gravels) stratum. The infiltration test was conducted
in accordance with the current City of Springfield Stormwater Quality Design Standards, which
references the City of Eugene Stormwater Management Manual - Encased Falling Head Test,
available at httos://www.eugene-or.gov/477/Stormwater-Management-Manual.
At the infiltration test location, a six inch diameter solid pvc pipe (stand pipe) was embedded
approximately three inches into the gravels at the bottom of the hole. We then filled the stand
pipe with a 12 -inch head of water for the initial pre-soaking trial. The 12 -inch head of water
completely infiltrated within 10 minutes (pre-soak trial was performed twice), therefore the
required four -hour -minimum pre-soak period was not required. According to the procedure
outlined in the City of Eugene Stormwater Management Manual (Appendix G) a minimum of
three trials is required at each location. Trials are to be conducted until the measured infiltration
rate between two successive trials does not increase and the percent change is minimal. A total
of seven trials were performed in IT -1. The average infiltration rate is then used to calculate the
unfactored infiltration rate (i.e. no Factor of Safety has been applied). Testing is conducted by
recording the time required for a 12 -inch head of water to infiltrate into the soil at 10 -minute
intervals for a total period of at least one hour or until all of the water has drained. The infiltration
test pit was loosely backfilled with the excavated soils upon completion. The final test result for
the test location (IT -1) is listed in Table 1 below.
Table 1: Infiltration Test Result
Infiltration
Trial Depth
Infiltration
Soil Stratum
Test
(feet)
Rate* (in/hr.)
Tested
Well -graded
IT -1
4
44
gravel with silt
and sand
*unfactored infiltration rate
2.5 Seismicity
In accordance with Section 1613.2.2 of the 2019 OSSC, we recommend a Site Class D (Stiff
Soil) for this site when considering the average of the upper 100 feet of bearing material
beneath the foundations. This recommendation is based on the results of our subsurface
investigation as well as our knowledge of the local geology. Inputting our recommended site
class, as well as the site latitude and longitude, into the Applied Technology Council (ATC) web -
based U.S. Seismic Design Maps tool available at httos://hazards.atcouncil.org, we obtained the
seismic design parameters shown in Table 2 below. The return interval is 2 percent probability
of exceedance in 50 years.
E Street Storage Facility Earth Engineers, Inc.
EEI Report No. 20.106.1 August 24, 2020
12 0122
Table 2: 2019 OSSC Seismic Design Parameter Recommendations
Parameter
Recommendation
Site Class
D
S,
0.649g
S,
0.375g
F.
1.281
F„
null
Sw (=S,*F,)
0.831g
S„ (=S,`F„)
null
SDS (=2t3`S,S)
0.554g
Design PGA (=SDS X2.5)
0.222g
MCE, PGA
0.307g
Fes,
1.293
PGA, ffp❑ x MCEe PGA)
0.397g
Note: Site Latitude = 44.0507720°, Site Longitude = -122.964639°
Per Section 11.4.8 of ASCE 7-16 a site-specific seismic site response analysis is required for
structures on Site Class D and E sites with S, greater than or equal to 0.2g. The S, value for
this site is greater than 0.2g as shown in Table 2 above. Therefore, a site response analysis is
required as part of the design phase (which we have not performed). However, Section 11.4.8
does provide an exception for not requiring a site response analysis (reference Sections
11.4.8.1, 11.4.8.2 and 11.4.8.3). The project Structural Engineer should determine if the
proposed buildings will meet any of the exceptions—if the buildings do not meet the exception
requirements then EEI should be retained to perform a site-specific site response analysis.
We understand a Supplement 1, dated December 12, 2018, has been issued for ASCE 7-16 to
correct some issues in the original publication. One of the corrections in Supplement 1 pertains
to Table 11.4-2 (Table 3 below) for determining the value of the Long -Period Site Coefficient,
Fv, which is then used to calculate the value of TS. The TS value is needed for one of the
exceptions in Section 11.4.8. Wthout the correction in Supplement 1, it would not be possible
to determine Fv and calculate T,. Based on Supplement 1, the Fv value may be determined from
the following corrected table (Table 3 below).
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EEI Report No. 20.106.1 August 24, 2020
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Table 3: Lona -Period Site Coefficient. FV (corrected Table 11.4-2 in ASCE 7-16).
Note: use linear Interpolation Tor intermediate values or J,.
'See requirements for site-specific ground motions in Section 11.4.8. These values of Fv
shall be used only for calculation of Ts.
In accordance with Section 1613.3.2 of the 2019 OSSC, we have included the following
evaluation of potential geologic and seismic hazards including slope instability, liquefaction, and
surface rupture due to faulting or lateral spreading.
The risk of slope instability on the subject property is considered low because there are no
slopes on the site. A review of the State of Oregon's online landslide map (SLIDO-4.0) shows
that the subject property is mapped in a low landslide risk hazard area.
In our professional opinion, the risk of liquefaction on the subject property is low when
considering the site geology and the consistency of the native "Bar Run" gravels encountered.
As part of our background research we visited the Oregon HazVu Statewide Geohazards web -
based Viewer available at hftps://qis.dogami.oregon.gov/mapsthazvu/. According to the viewer,
the site is not mapped within the Effective FEMA 100 year Flood plain.
The risk of earthquake surface rupture on the subject property is considered low due to the lack
of mapped faults at or near the site based on our review of the United States Geological
Survey's web site and Interactive Fault Map at http://earthguake.usgs.gov/hazards/qfaults/map.
It should be noted that it is possible for faults to be present, which are not currently mapped.
E Street Storage Facility Earth Engineers, Inc.
EEI Report No. 20.106.1 August 24, 2020
Mapped Risk -Targeted Maximum Considered Earthquake (MCR)Spectral
Response Acceleration Parameter at 1-s Period
Site Class
S,<=0.1
I S,<=0.2
S,<=0.3
I S,<=0.4
S,<=0.5
S,<=0.6
A
0.8
0.8
0.8
0.8
0.8
0.8
B
0.8
0.8
0.8
0.8
0.8
0.8
C
1.5
1.5
1.5
1.5
1.5
1.4
D
2.4
2.2'
2.0'
1.9'
1.8'
1.7'
E
4.2
3.3'
2.8'
2.4'
2.2'
2.0'
F
See Section
11.4.8
See Section
11.4.8
See Section
11.4.8
See Section
11.4.8
See Section
11.4.8
See Section
11.4.8
Note: use linear Interpolation Tor intermediate values or J,.
'See requirements for site-specific ground motions in Section 11.4.8. These values of Fv
shall be used only for calculation of Ts.
In accordance with Section 1613.3.2 of the 2019 OSSC, we have included the following
evaluation of potential geologic and seismic hazards including slope instability, liquefaction, and
surface rupture due to faulting or lateral spreading.
The risk of slope instability on the subject property is considered low because there are no
slopes on the site. A review of the State of Oregon's online landslide map (SLIDO-4.0) shows
that the subject property is mapped in a low landslide risk hazard area.
In our professional opinion, the risk of liquefaction on the subject property is low when
considering the site geology and the consistency of the native "Bar Run" gravels encountered.
As part of our background research we visited the Oregon HazVu Statewide Geohazards web -
based Viewer available at hftps://qis.dogami.oregon.gov/mapsthazvu/. According to the viewer,
the site is not mapped within the Effective FEMA 100 year Flood plain.
The risk of earthquake surface rupture on the subject property is considered low due to the lack
of mapped faults at or near the site based on our review of the United States Geological
Survey's web site and Interactive Fault Map at http://earthguake.usgs.gov/hazards/qfaults/map.
It should be noted that it is possible for faults to be present, which are not currently mapped.
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EEI Report No. 20.106.1 August 24, 2020
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3.0 EVALUATION AND FOUNDATION RECOMMENDATIONS
3.1 Geotechnical Discussion
The primary geotechnical factors influencing the proposed construction are the following:
• The presence of undocumented fine-grained fill to depths of up to 15 inches below
existing site grades and organic rich topsoil to depths of up to 30 inches below
existing site grades. We do not recommend supporting the proposed building
foundations, floor slabs or pavements directly on these soils.
In our opinion, it is acceptable to construct the proposed building and pavements on the subject
property, provided the recommendations in this report are followed as outlined below.
3.2 General Site Preoaration
Prior to the start of any earthwork, the test pit locations performed for our subsurface investigation
should be located, excavated to their bottoms, and backfilled with granular structural fill in properly
compacted lifts, under the observation of a representative of the Geotechnical Engineer.
As noted in Section 3.1 above, we do not recommend supporting the proposed building
foundations, floor slabs or pavements directly on either the undocumented fill material or the
organic rich topsoil layer encountered at the site. Where these materials are under structurally
improved areas, they should be removed and replaced with properly compacted structural fill as
described in Section 3.3 below.
Any vegetation, roots, and any other deleterious soils should be stripped and removed from
beneath structurally improved areas.
After stripping and excavating to the proposed subgrade level, as required, the building pad
subgrade areas should be observed by a representative of the Geotechnical Engineer and
proofrolled with a fully loaded tandem axle dump truck. If the subgrade cannot be accessed with
a dump truck to perform a proofroll, then the subgrade will need to be evaluated by a
representative of the Geotechnical Engineer by soil probing. Structural fill, as described in
Section 3.3 below, should be placed on the prepared subgrade after it has been proofrolled or
soil probed. Soils that are observed to be soft or are otherwise judged to be unsuitable should
be undercut and replaced with properly compacted structural fill.
When fine-grained soils are exposed, it is not uncommon for construction equipment to severely
disturb the upper one to two feet of the subgrade during initial phases of site clearing and
grubbing, especially if site preparation work is performed during wet weather. This may result in
the need for undercutting and replacement of the disturbed soils if care is not taken by the
contractor to protect the moisture sensitive soils. The contractor may also need to construct
temporary construction roads to protect the subgrade soils from becoming disturbed. If fine -
E Street Storage Facility Earth Engineers, Inc.
EEI Report No. 20.106.1 August 24, 2020
15 of 22
grained soils are exposed and repeated construction traffic is anticipated, we recommend
covering these areas with 18 to 24 inches of coarse gravel underlain by a geotextile fabric to
prevent soil contamination of the rock and to protect the underlying subgrade.
3.3 Structural Fill
We recommend structural fill consist of imported crushed rock gravel or in-place crushed rock
gravel provided the material is relatively clean, free of deleterious materials (i.e. organics) and
has a maximum particle size of 3 to 4 inches. We do not recommend the use of the in-place
fine-grained sandy lean clay soils encountered in our subsurface explorations as structural fill
due to the over -optimum in-situ moisture condition and due to the fact that these soils will likely
be difficult to properly moisture condition, especially if earthwork construction takes place in the
wet season (generally October through June).
If crushed rock gravel is imported to the site, it should be relatively well graded and have a
maximum particle size of 1-% inches. Structural fill materials should be free of organics or other
deleterious materials, be relatively clean (i.e. less than 5 percent soil passing the U.S. #200
sieve), well graded, and have a liquid limit less than 45 and plasticity index less than 25.
All structural fill should be compacted to a minimum of 95 percent of the maximum dry density
as determined by the Modified Proctor. The Modified Proctor can either be the ASTM D1557 or
AASHTO T180 test methods. When placed, the lift thickness should generally not exceed 12
inches prior to compacting. The type of compaction equipment used will ultimately determine
the maximum lift thickness. In addition, we recommend that the structural fill be placed within +/-
2 percent of the optimum moisture for that material.
A representative of the Geotechnical Engineer should approve any selected granular fill material
before importing it to the site. Each lift of compacted engineered fill should be evaluated by a
representative of the Geotechnical Engineer prior to placement of subsequent lifts. The fill
should extend horizontally outward beyond the exterior perimeter of the building and pavement
areas at least five feet and three feet, respectively, prior to sloping.
Where fills are constructed on slopes steeper than 5H: 1V, the slope should be benched prior to
fill placement. Level benches should be a minimum of four feet wide laterally and should be cut
into the slope for no more than every five feet of vertical rise. The placement of structural fill
should begin at the base of the slope. All benches should be inspected by a representative of
the Geotechnical Engineer and approved prior to placement of structural fill lifts. If evidence of
seepage is observed in the bench excavations, a supplemental drainage system may need to
be designed and installed to prevent hydrostatic pressure buildup behind the fill. Fill and cut
slopes and disturbed natural soil slopes should be graded no steeper than 2H: 1V. Areas of the
slope which are not disturbed may be left at their current grade. Given the current grades at the
project site, fill benches are not anticipated to be necessary.
E Street Storage Facility Earth Engineers, Inc.
EEI Report No. 20.106.1 August 24, 2020
16 of 22
3.4 Foundation Recommendations
Based on the soils encountered in our test pits, an assumed maximum column load of 50 kips for
the proposed office building, the results of our laboratory testing, and our current understanding of
the project, it is our professional opinion that the proposed foundations forthe office building should
be supported on at least 8 inches of propedy compacted granular structural fill, as described in
Section 3.3 above, overlying the native, stiff to very stiff, sandy lean clay (CL) soils encountered in
our explorations.
We recommend footings be designed for a maximum net allowable soil bearing pressure of 2,500
pounds per square foot (psr) when bearing on at least 8 inches of propedy compacted granular
structural fill overlying the native, stiff to very stiff sandy lean clay (CL) stratum.
The width of the granular structural fill beneath the footing should be equal to the footing width
plus the thickness of the granular structural fill.
We recommend the proposed pole foundations (typically 18 or 24 inch diameter) for the storage
buildings bear directly on the native, medium dense to dense well -graded gravel with silt and sand
that was encountered between 4 and 5 feet below existing site grades or on a concrete pad
overlying the native, medium dense to dense well -graded gravel with silt and sand. We
recommend that the backfill adjacent to the pole foundations be concrete designed for a minimum
of 2,500 psi compressive strength at 28 days. If structural fill is used as backfill adjacent to the pole
foundations, then the structural fill should be placed and mechanically compacted in accordance
with Section 3.3 above. The backfill should be placed up to the bottom of either the slab or footing
grade, whichever applies.
The allowable soil bearing pressure is based on dead load plus design live load. The allowable
soil bearing pressure recommended above can be increased by one-third for short term wind or
seismic loads. Minimum dimensions of 24 inches for isolated column footings and 18 inches for
continuous wall footings should be used to minimize the possibility of a local bearing capacity
failure.
The foundation excavations should be observed by a representative of the Geotechnical
Engineer prior to steel or concrete placement to assess that the foundation materials are
capable of supporting the design loads and are consistent with the materials discussed in this
report. Unsuitable soil zones encountered at the bottom of the foundation excavations should be
removed to the level of suitable soils or properly compacted structural fill as directed by the
Geotechnical Engineer. Cavities formed as a result of excavation of unsuitable soil zones
should be backfilled and compacted with structural fill in accordance with Section 3.3 above.
Exterior footings and foundations in unheated areas should be located at a depth of at least 12
inches below the final exterior grade to provide adequate frost protection. If the building is to be
constructed during the winter months or if the foundation soils will likely be subjected to freezing
temperatures after foundation construction, then the foundation soils should be adequately
E Street Storage Facility Earth Engineers, Inc.
EEI Report No. 20.106.1 August 24, 2020
17 of 22
protected from freezing. Surface run-off water should be permanently drained away from the
foundation excavations and not allowed to pond.
Lateral frictional resistance between the base of footings and the subgrade can be expressed as
the applied vertical load multiplied by a coefficient of friction of 0.35 for concrete foundations
bearing directly on crushed rock gravel. In addition, lateral loads may be resisted by passive
earth pressures based on an equivalent fluid density of 300 pounds per cubic foot (pcf) for
footings poured "neat' against in-situ soils, or properly backfilled with structural fill. These are
ultimate values - we recommend a factor of safety of 1.5 be applied to the equivalent fluid
pressure, which is appropriate due to the amount of movement required to develop full passive
resistance.
Provided our recommendations above are followed, we do not anticipate that total and
differential settlement will exceed the typical values of 1 inch and %-inch, respectively.
Please note that our subsurface investigation was limited to the areas explored. At a minimum,
we recommend that during construction we observe all footing and floor slab excavations to
observe that the material is similar to what we observed during our subsurface investigation
and, subsequently, similar to the material our recommendations are based on.
3.5 Floor Slab Recommendations
For the purposes of this report, we have assumed that maximum floor slab loads will not exceed
150 psf. In order to provide uniform subgrade reaction beneath floor slabs, we recommend
supporting floor slabs on a minimum of 12 inches of properly compacted granular structural fill
(as outlined in Section 3.3 above) overlying the native, stiff to very stiff sandy lean clay (CL)
stratum.
Prior to placing the structural fill, the exposed subgrade surface should be prepared as
discussed in Section 3.2 and then proofroll tested with a fully loaded, dual axle dump truck in
order to identify any unstable areas that should be removed prior to structural fill placement. The
proofroll should be observed by a representative of the Geotechnical Engineer. If the subgrade
cannot be accessed with a dump truck, then the subgrade will need to be visually evaluated by
a representative of the Geotechnical Engineer by soil probing. If fill is required, the structural fill
should be placed on the prepared subgrade after it has been proofrolled or soil probed.
The structural fill should provide a capillary break to limit migration of moisture through the slab.
If additional protection against moisture vapor is desired, a moisture vapor retarding membrane
may also be incorporated into the design. Factors such as cost, special considerations for
construction, and the floor coverings suggest that decisions on the use of vapor retarding
membranes be made by the project design team, the contractor and the owner.
E Street Storage Facility Earth Engineers, Inc.
EM Report No. 20.106.1 August 24, 2020
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3.6 Pavement Recommendations
Our scope of services included evaluating the surface soils for the specific purpose of a detailed
pavement analysis. Using the AASHTO method of flexible pavement design, the following design
parameters have been assumed:
• An assumed California Bearing Ratio (CBR) value of 5 for the sandy lean clay (CL) stratum
that underlies the proposed new parking and driveway pavement areas.
• A pavement life of 20 years.
• A terminal serviceability (Pt) of 2 (i.e. poor condition).
• A regional factor (R) of 3.0.
• An assumed 18,000 -pound equivalent single axle load (ESAL) of:
5 per day for automobile parking areas (light duty) and 50 per day for automobile drive
lanes (heavy duty).
• An assumed average weight of 6,000 pounds per car was used in our calculations.
Table 4: Asphaltic Concrete - Recommended Minimum Thicknesses (inches)
Table 5: Portland Cement Concrete - Recommended Minimum Thicknesses (inches)
Pavement Materials
Parking
Drive Lanes
Pavement Materials
Areas (Light
(heavy duty)
Crushed Aggregate Base Course (underlain by
Duty)
8
Asphaltic Concrete
3
3
Crushed Aggregate Base Course (underlain by
10
12
Mirafi 500X geotextile fabric or equivalent)
Table 5: Portland Cement Concrete - Recommended Minimum Thicknesses (inches)
Pavement Materials
Car Parking
Driveway
Areas
Portland Cement Concrete
5
5
Crushed Aggregate Base Course (underlain by
6
8
Mirafi 500X geotextile fabric or equivalent)
The project Civil Engineer should review our assumptions to confirm they are appropriate for the
anticipated traffic loading.
After the site has been prepared in accordance with Section 3.2 of this report, the pavement
subgrade should be proofrolled with a fully loaded dual axle dump truck. Areas found to be soft or
yielding under the weight of a dump truck should be overexcavated as recommended by the
Geotechnical Engineer's representative and replaced with additional base course.
The geotextile fabric should be placed over a smooth subgrade and should be placed with no
wrinkles. The fabric should be overlapped a minimum of 18 inches. Construction equipment should
not be permitted to travel directly on the geotextile fabric.
The base course should consist of structural fill as described in Section 3.3 of this report. The
E Street Storage Facility Earth Engineers, Inc.
EEI Report No. 20.106.1 August 24, 2020
10 of 22
base course should be moisture conditioned to within 2 percent of optimum and compacted to a
minimum of 95 percent of a modified Proctor as outlined in Section 3.3.
Asphaltic concrete materials
should be compacted to
at least 91 percent of
the material's
theoretical maximum density
as determined in general
accordance with ASTM
D2041 (Rice
Specific Gravity).
Water should not be allowed to pond behind curbs and saturate the base course. In down grade
areas, base course should extend through the slope to allow any water entering the base course a
path to exit.
E Street Storage Facility Earth Engineers, Inc.
EEI Report No. 20.106.1 August 24, 2020
20 of 22
4.0 CONSTRUCTION CONSIDERATIONS
EEI should be retained to provide observation and testing of construction activities involved in
the foundation, earthwork, and related activities of this project. EEI cannot accept any
responsibility for any conditions that deviate from those described in this report, nor for the
performance of the foundations, if not engaged to also provide construction observation for this
project.
4.1 Drainage and Groundwater Considerations
Water should not be allowed to collect in the foundation excavations or on prepared subgrades for
the floor slab during construction. Positive site drainage should be maintained throughout
construction activities. If groundwater is encountered, a system of sumps and pumps may be
required to keep footing excavations drained until the footing is placed to prevent softening of the
subgrade soils. Undercut or excavated areas should be sloped toward one comer to facilitate
removal of any collected rainwater, groundwater, or surface runoff. The site grading plan should be
developed to provide rapid drainage of surface water away from the building and pavement areas
and to inhibit infiltration of surface water around the perimeter of the building and beneath the floor
slab. The grades should be permanently sloped away from building areas. Stormwater runoff
should be piped (tightlined) to an approved on-site private system or public storm drain system.
4.2 Moisture Sensitive Soils
The upper fine-grained soils encountered at this site are expected to be sensitive to
disturbances caused by construction traffic and to changes in moisture content. During wet
weather periods, increases in the moisture content of the soil can cause significant reduction in
the soil strength and support capabilities. In addition, fine-grained soils that become wet may be
slow to dry and thus significantly retard the progress of grading and compaction activities.
The surface soils at this site, if wet, may be prone to rutting when driven over by vehicles.
Additionally, it is not uncommon for construction equipment to severely disturb the upper 1 to 2
feet of the subgrade during initial phases of site clearing, grubbing, demolition, etc., especially if
site preparation work is performed during wet weather, as is currently planned by the project
team. This may result in the need for undercutting and replacement of the disturbed soils if care
is not taken by the contractor to protect the moisture sensitive soils. The contractor may also
need to construct temporary construction roads. If fine-grained soils are exposed and repeated
construction traffic is anticipated, we recommend covering these areas with 18 to 24 inches of
coarse gravel underlain by a geotextile fabric to prevent soil contamination of the rock and to
protect the underlying subgrade.
E Street Storage Facility Earth Engineers, Inc.
EEI Report No. 20.106.1 August 24, 2020
21 of 22
4.3 Excavations
In Federal Register, Volume 54, No. 209 (October 1989), the United States Department of
Labor, Occupational Safety and Health Administration (OSHA) amended its "Construction
Standards for Excavations, 29 CFR, part 1926, Subpart P". This document and subsequent
updates were issued to better insure the safety of workmen entering trenches or excavations. It
is mandated by this federal regulation that excavations, whether they be utility trenches,
basement excavations or footing excavations, be constructed in accordance with the new OSHA
guidelines. These regulations are strictly enforced and if they are not closely followed, the owner
and the contractor could be liable for substantial penalties. The contractor is solely responsible
for designing and constructing stable, temporary excavations and should shore, slope, or bench
the sides of the excavations as required to maintain stability of both the excavation sides and
bottom. The contractor's "responsible person", as defined in 29 CFR Part 1926, should evaluate
the soil exposed in the excavations as part of the contractor's safety procedures. In no case
should slope height, slope inclination, or excavation depth, including utility trench excavation
depth, exceed those specified in local, state, and federal safety regulations. We are providing
this information solely as a service to our client. EEI does not assume responsibility for
construction site safety or the contractor's compliance with local, state, and federal safety or
other regulations.
E Street Storage Facility Earth Engineers, Inc.
EM Report No. 20.106.1 August 24, 2020
22 of 22
5.0 REPORT LIMITATIONS
As is standard practice in the geotechnical industry, the conclusions contained in our report are
considered preliminary because they are based on assumptions made about the soil, rock, and
groundwater conditions exposed at the site during our subsurface investigation. A more
complete extent of the actual subsurface conditions can only be identified when they are
exposed during construction. Therefore, EEI should be retained as your consultant during
construction to observe the actual conditions and to provide our final conclusions. If a different
geotechnical consultant is retained to perform geotechnical inspection during construction then
they should be relied upon to provide final design conclusions and recommendations, and
should assume the role of geotechnical engineer of record, as is the typical procedure required
by the governing jurisdiction.
The geotechnical recommendations presented in this report are based on the available project
information, and the subsurface materials described in this report. If any of the noted information
is incorrect, please inform EEI in writing so that we may amend the recommendations presented
in this report, if appropriate, and if desired by the client. EEI will not be responsible for the
implementation of its recommendations when it is not notified of changes in the project. Once
construction plans are finalized and a grading plan has been prepared, EEI should be retained
to review those plans, and modify our existing recommendations related to the proposed
construction, if determined to be necessary.
The Geotechnical Engineer warrants that the findings, recommendations, specifications, or
professional advice contained herein have been made in accordance with generally accepted
professional geotechnical engineering practices in the local area. No other warranties are
implied or expressed. This report has been prepared for the exclusive use of the client, North
Lake Property Management, for the specific application to the design and construction of the
proposed new Storage Buildings and associated pavements to be located at 4155 E Street in
Springfield, Oregon. EEI does not authorize the use of the advice herein nor the reliance upon
the report by third parties without prior written authorization by EEI.
E Street Storage Facility Earth Engineers, Inc.
EEI Report No. 20.106.1 August 24, 2020
APPENDICES
E Street Storage Facility Earth Engineers.. Inc.
EEI Report No. 20-106-1 August 24. 2020
APPENDIX A -
TEST PIT LOGS
E Street Storage Facility Earth Engineers.. Inc.
EEI Report No. 20-106-1 August 24. 2020
Appendix A: Test Pit TP -1
Earth
Shed 1 ort
Engineers,
North Properly Management Report Number: 20-106-1
Client: NaLake Pro
Prgee: New Storage Buildings Excavation Contractor Client
I11C
Site Address: 4155 E Street, Springfield, Oregon W477 Excavation Method: Mini -Excavator
Locdion or Ted HE WN, 35W,ASE properly cane Equipment: Takeuchi T870,18" wide toothed bucker
Ode Excavated: 7l7/2020 Approximate Elevation (ft ms1): 475
Logged By: Ray Alipeli
Ulthology,
Sampling
Data
e
- —
Geologic Oeapiplion or
v `mNin
4
Remarks;
E
L E
Soil and Rock Strata
E
"`
u c
or o
v
IS i
V
w
d`o
o
0
Fill -mixture offine-grdned silty claylclayey sill with
Easy
Approximatdyginches thick
rounded gravels, brown, mast, soft, some roots up to 12"
diameter
1
S
Topsoil - dark broken to black, all dill organics
Easy
ineud ing grass pods and some tree roots up 1012"
diameter
2.0
30
2
SWdy Isar Clay (CL) - red-0pown, mast, dm
Mod.
3
1.75
67
28
4
5
0 •
We11-graded a rawl witlr sill art sad (locally repeated
0
to as'bar-run" Walsall) - gray, mast, dense to say dense
Hard
0 .
6
0'
•0•
o -
•0•
7
O0•
0 -
0•
0 -
B
g
0-
I
12
13
14
5
Nates: Test pit terminated at an approximate depth of 8 feet below existing ground surface. Groundwater was not encountered at the lime of our exploration.
Test pit was loosely backfilled with excavated soil on July 7, 2020. Approximate elevation based on Google Earth. Mod. - Moderate.
Appendix A: Test Pit TP -2
Earth
Shed 1011
Engineers,
Client: Nath Lake Properly Management Report Number: 20-106-1
Protect: New Storage euddngs Excavation Contractor Client
I11C
Site Addressed 4155 E Sired, Springfield, Oregon W477 Excavation Method: Mini -Excavator
Localion aTed Pit: WN, 35W,ASE property sonar Equipment: Takeuchi T870,18" wide toothed bucket
Ode Excavded: 7l7/2020 Approximate Elevation q: cost: 475
Logged! By: Ray Aliparli
lihology
Sampling
Data
ec
—
Geologic Description of
—a
e
RemarksSoil
E
and Rock Strata
E 2
mo
u c
o
orE
c
F E
.0
ry
0
Fill -mixture offine-grained silty clay/clayey silt with
EasyApproximately
15inchee
rounded gravels, brown, molal, soft, some roots up to 1/2"
Ihid
diameter
1
Topsoil- dark brown to blactc, model, stiff, organics
Easy
including grass mals
2-
~
2.0
NJ
Sandy leen Clay (CL) - red4rown, mast, diff
Mod.
3 —
4
1.5
85
35
29
29
Pladaty loiter = 10
5
0
Wel I -graded Gravel with will anal sand )Incally retained
Hard
o•
un"
to as "bar-rgravel) - gray, mad, dense to wry dense
0 .
6
0'
•0•
o -
•0•
.0•
o -
0•
0 -
B
g
0
1
12
13
14
5
Notes Test pit terminated at an approximate depth of 8 feet below existing ground surface. Groundwater was not encountered at the time of our exploration.
Test pit was loosely backfilled with excavated soil on July 7, 2020. Approximate elevation based on Google Earth. Mod. = Moderate.
Appendix A: Test Pit TP -3
Earth
Shed 1 all
Engineers,
Client: Nath Lake Properly Management Report Number: 20-106-1
Prgecl: New Storage eudtlngs Excavation Contractor Client
I11C
Site Address: 4155 E Street, Springfield, Oregoo W477 Excavation Method: Mini -Excavator
Localim plied Rd: SON, 35W aSE properly para Equipment: Takeuchi T870,18" wide toothed bucket
Ode Excavated: 7l7/2020 Approximate Elevation (ft rust: 475
Logged By: they Aliperli
Lithology
Sampling
Data
e
-
-
- d
Geologic Description of@@�
_
Nin
ro
4
Remarks
Soil and Rock Strata
E
��
oN.
_
q' -
O5
1 en
1010
sic
.4.E
0
Fill - mixture offine-grained silty clay/clayey silt with
Easy
Approximately 15inphes
rounded gravels, brown, moial, soft, some roots up to 1/2"
thick
diameter
1
Topsoil- dark brown to blade, moist, stiff, organics
� y
including grass apple
2-
~
2.0
22
Samly leen Clay (CL) -reit-0rawn, mend, diff
Mod.
3
2.5
39
4Well-graded
Gravel with all arid!sand (locally referred
Hand
0.
to as"bar-run" gravel) - gray, m dial dense to very dense
.O•
5
O'
•O•
O•
•O•
B
O•
7
8
0
0
1
12
13
14
5
Notes'. Test pit terminated at an approximate depth of 6 feet below existing ground surface. Groundwater was not encountered at the time of our exploration.
Test pit was loosely backfilled with excavated soil on July 7. 2020. Approximate elevation based on Google Earth. Mad. = Moderate.
APPENDIX B -
SOIL CLASSIFICATION LEGEND
E Street Storage Facility Earth Engineers.. Inc.
EEI Report No. 20-106-1 August 24. 2020
APPENDIX B: SOIL CLASSIFICATION LEGEND
APPA RENT CONSISTENCY OF COHESIVE SOILS IPECK, HANSON& THORNBURN 1974, AASNTO 1988
Descriptor
SPT Nm
blowslfoot •
Pocket Penetrometer,
Qp Itsf)is
Torvane
Field Approximation
Very Safi
< 2
<0.25
< 0.12
Easily penetrated several inches by fist
Soft
2-4
0.25-0.50
0.12-0.25
Easily penetrated several inches by thumb
Medium Stiff
5-8
0.50-1.0
0.25-0.50
Penetrated several inches by thumb w/moderateeffort
Stiff
9-15
1.0-2.0
0.50-1.0
Readily indented by thumbnail
Very Stiff
16-30
2.0-4.0
1.0-2.0
Indented by thumb but penetrated only with great effort
Hard
> 30
> 4.0
> 2.0
Indented by thumbnail with difficulty
`Using SPTN¢ is considered a crude approximation for cohesivesails.
APPARENT DENSITY OF COHESIONLESS
SOILS AAswo19BB
Descriptor
SPT Nm Value (blowstfoet)
Very Loose
0-4
Loose
5-10
Medium Dense
11-30
Dense
31-50
Very Dense
> 50
PERCENT OR PROPORTION OF SOILS
ASTM 132488-08
Descriptor Criteria
Trace Particles are present but estimated < 5%
Few 5-10%
Little 15-25%
Some 30-45%
Mostly 50-100%
Percentages are estimated to nearest 5% in the field.
Use 'about" unless percentages are based on
laboratory testing.
MOISTURE
(ASTM 13248808)
Descriptor
Criteria
> 12 inches
Absence of moisture, dusty, dry to the touch, well
Dry
below optimum moisture content (per ASTM
%inch to 3 inches
No.4 sieve to%inch
D698 or D1557
Moist
Damp but no visible water
Passing No. 200 slew 0.075mm)
Visible free water, usually soil is below water
Wet
table, well above optimum moisture content (per
Siltyravels and ravel -sand -silt mixtures
ASTM D698 or D1557
SOIL PARTICLE SIZE
ASTM 132488-08
Descriptor
Size
Boulder
> 12 inches
Cobble
3 to 12 inches
Gravel - Coarse
Fine
%inch to 3 inches
No.4 sieve to%inch
Sand - Coarse
Medium
Fine
No. 10to Na. 4siewe 4.75mm)
No. 40 to No. 10 slew 2mm)
No. 200 to No. 40 sieve (.425mm)
Silt and Clay ('fines")
Passing No. 200 slew 0.075mm)
GRAPHIC SYMBOL LEGEND
® GRAB Grab sample
SPT Standard Penetration Test 2° OD),ASTM Of 586
Engineers, ST I I Shelby Tube, ASTM 131587(pushed)
jnc DM I Dames and Moore ring sampler 3.25' OD and 140 -pound hammer
CORE I Rackcoring
UNIFIED SOIL CLASSIFICATION SYSTEM [ASTM 1324118
Major Division
Group
Symbol
Description
Coarse
Grained
Soils
Gravel (50% or
an Na. eve)
on No. 4slew)
Clean
GravelGP
GW
Well -graded ravels and ravel -sand mixtures little or no fines
Poorly graded gravels and ravel -sand mixtures, little or no fines
Gravel
with fines
GM
Siltyravels and ravel -sand -silt mixtures
GC
Clayey ravels andgravel-sand-clay mixtures
(mare than
50% retained
on #200
sieve)
Sand (> 50%
passing No. 4-g.nd
sieve)Silty
Clean
sand
SW
ra
Well -graded sands and ravel) sands, little or no fines
SP
Pood raded sands and gravelly sands little or no fines
with fines
SM
sands and sand -silt mixtures
SC
Clayey sands and sand -clay mixtures
Fine Grained
Soils
Silt and Clay
(liquid limit < 50)
ML
I Ina anic silts, rack fiourand clayeysilts
CL
Ina anic clays of low -medium plasticity,gravelly, sandy &lean clays
OL
I Orrianic silts and organic silty clays of low plasticity
(50% ormare
passing#200
sieve)
Silt and Clay
(liquid limit>50)
MH
Ina anicsilts andcla a silts
CH
Inorganic clays or highplasticity,fat clays
OH
I Organic clays etmedium to high plasticity
Highly
Organic Soils
PT
I Peat, muck and other highly organic sails
GRAPHIC SYMBOL LEGEND
® GRAB Grab sample
SPT Standard Penetration Test 2° OD),ASTM Of 586
Engineers, ST I I Shelby Tube, ASTM 131587(pushed)
jnc DM I Dames and Moore ring sampler 3.25' OD and 140 -pound hammer
CORE I Rackcoring