HomeMy WebLinkAboutStudies Applicant 9/12/2023 (2)Carlson Geotechnical Bend Office (541)330-9155Gp RL`S0
A division of Carlson Testing, Inc. Eugene Office (541) 345-0289
Phone: (503) 601-8250 Salem Office (503)589-1252
www.carlsontes[ino.cam
Tigard Office (503) 684-3460
Report of
Geotechnical Investigation & Infiltration Testing
Anytime Self Storage Springfield
High Banks Road & 52nd Street
Springfield, Oregon
CGT Project Number G2305919
Prepared for
Brandon Bennett
Signal Ventures
2538 NE Division Street
Bend, Oregon 97703
June 21, 2023
Office: 18270 SW Boones Ferry Road, Suite 6, Durham, Oregon 97224
Mailing: P.O. Box 230997, Tigard, Oregon 97281
Carlson Geotechnical Bend Office (541)330-9155
Eugene Office (541) 345-0289
A division of Carlson Testing, Inc. Salem Office (503) 589-1252
Phone: (503) 601-8250 Tigard Office (503)684-3460
wwa cadsontestinc.com
June 21, 2023
Brandon Bennett
Signal Ventures
2538 NE Division Street
Bend, Oregon 97703
Report of
Geotechnical Investigation & Infiltration Testing
Anytime Self Storage Springfield
High Banks Road & 52nd Street
Springfield, Oregon
CGT Project Number G2305919
Dear Brandon Bennett:
Carlson Geotechnical (CGT), a division of Carlson Testing, Inc. (CTI), is pleased to submit this report
summarizing the results of our geotechnical investigation and infiltration testing for the proposed Anytime
Self Storage Springfield project. The site is located southwest of the intersection of High Banks Road and
52n0 Street in Springfield, Oregon. We performed our work in general accordance with CGT Proposal
GP21-102, dated May 8, 2023. Written authorization for our services was received on May 9, 2023.
We appreciate the opportunity to work with you on this project. Please contact us at (503) 601-8250 if you
have any questions regarding this report.
Respectfully Submitted,
CARLSON GEOTECHNICAL
Ariana Tenold, G.I.T.
Geotechnical Project Manager
atenoldCdcarlsontestino.com
Doc ID: G:\GEOTECH\PROJECTS\2023 Projects\G2305919
Deliverables\Repad\62305919 Geotechnical Investigation.docx
Brad M. Wilcox, P.E., G.E.
Principal Geotechnical Engineer
bwilcox(ftarlsomesti nc.com
Anytime Self Storage Springfield\02305919 - GEO\008 -
Office: 18270 SW Boones Ferry Road, Suite 6, Durham, Oregon 97224
Mailing: P.O. Box 230997, Tigard, Oregon 97281
Anytime Self Storage Springfield
Springfield, Oregon
CGT Project Number G2305919
June 21. 2023
1.0
INTRODUCTION....................................................................................................................................4
SitePlan.................................................................................................................................................
1.1
Project Information...........................................................................................................................4
Figure 3
1.2
Scope of Services.............................................................................................................................4
Retaining Wall Surcharge Pressures......................................................................................................
2.0
SITE DESCRIPTION..............................................................................................................................5
2.1
Site Geology......................................................................................................................................5
2.2
Site Surface Conditions...................................................................................................................5
2.3
Subsurface Conditions....................................................................................................................5
3.0
SEISMIC CONSIDERATIONS...............................................................................................................7
3.1
Seismic Design.................................................................................................................................7
3.2
Seismic Hazards...............................................................................................................................7
4.0
CONCLUSIONS.....................................................................................................................................9
5.0
RECOMMENDATIONS..........................................................................................................................9
5.1
Site Preparation..............................................................................................................................
10
5.2
Temporary Excavations.................................................................................................................
11
5.3
Wet Weather Considerations.........................................................................................................
11
5.4
Structural Fill...................................................................................................................................
13
5.5
Shallow Foundations......................................................................................................................
15
5.6
Rigid Retaining Walls.....................................................................................................................
16
5.7
Floor Slabs......................................................................................................................................
18
5.8
Pavements.......................................................................................................................................
19
5.9
Additional Considerations.............................................................................................................21
6.0
RECOMMENDED ADDITIONAL SERVICES......................................................................................21
6.1
Design Review.................................................................................................................................21
6.2
Observation of Construction.........................................................................................................21
7.0
LIMITATIONS.......................................................................................................................................22
SiteLocation...........................................................................................................................................
Figure 1
SitePlan.................................................................................................................................................
Figure 2
SitePhotographs....................................................................................................................................
Figure 3
Retaining Wall Static & Seismic Pressure Distribution...........................................................................
Figure 4
Retaining Wall Surcharge Pressures......................................................................................................
Figure 5
Subsurface Investigation and Laboratory Testing............................................................................. Appendix A
Results of Infiltration Testing.............................................................................................................Appendix B
Carlson Geotechnical Page 3 of 22
Anytime Self Storage Springfield
Spingfieid, Oregon
CGT Propct Number G2305919
June 21, 2023
1.0 INTRODUCTION
Carlson Geotechnical (CGT), a division of Carlson Testing, Inc. (CTI), is pleased to submit this report
summarizing the results of our geotechnical investigation and infiltration testing for the proposed Anytime
Self Storage Springfield project. The site is located southwest of the intersection of High Banks Road and
521" Street in Springfield, Oregon, as shown on the attached Site Location, Figure 1.
1.1 Project Information
CGT developed an understanding of the proposed project based on review of project documents provided to
us in mid-March 2023 and late April 2023 and subsequent correspondence. Based on our review, we
understand the project will include:
• Construction of seven new self -storage buildings, designated Buildings A through F, at the approximate
2.7 -acre site. Although no architectural information has been provided, we anticipate the buildings will be
one- to two -stories, wood- and/or metal -framed, and incorporate slab -on -grade ground floors. No below -
grade levels (basements) are planned. We have assumed maximum column, continuous wall, and
uniform floor slab loads will be on the order of 30 kips, 2 kips per lineal foot (klf), and 250 pounds per
square foot (psf), respectively
• Construction of new, asphalt -surfaced drive lanes to access the storage buildings.
• Installation of underground utilities to serve the storage buildings.
• Although no stormwater management plans have been provided, we understand that, if conditions allow,
stormwater collected from new impervious areas of the site will be diverted, at least in part, to on-site
stormwater infiltration facilities. Design of the stormwater facilities will rest with others. As part of the
investigation, six infiltration tests were requested by the project civil engineer at maximum depths of 5
feet below ground surface (bgs).
• Although no grading plans have been provided, we anticipate permanent grade changes at the relatively
level site will be minimal, with maximum cuts and fills on the order of 3 feet in depth.
1.2 Scope of Services
Our scope ofwork included the following:
• Contact the Oregon Utilities Notification Center to mark the locations of public utilities within a 20 -foot
radius of our explorations at the site.
• Explore subsurface conditions at the site by observing the excavation of six test pits to depths of up to
about 10 feet below ground surface (bgs). Details of the subsurface investigation are presented in
Appendix A.
• Conduct six infiltration tests in the above mentioned test pits. Results of the infiltration testing are
presented in Appendix B.
• Classify the soils encountered in the explorations in general accordance with ASTM D2488 (Visual -
Manual Procedure).
• Provide a technical narrative describing surface and subsurface deposits, and local geology of the site,
based on the results of our explorations and published geologic mapping.
• Provide recommendations for the Seismic Site Class, mapped maximum considered earthquake spectral
response accelerations, and site seismic coefficients.
Carlson Geotechnical Page 4 of 22
Anytime Setl Storage Springfield
Springfield, Oregon
CGT Project Number G2305919
June 21, 2023
• Provide a qualitative evaluation of seismic hazards at the site, including earthquake -induced liquefaction,
landsliding, and surface rupture due to faulting or lateral spread.
• Provide geotechnical recommendations for site preparation and earthwork.
• Provide geotechnical engineering recommendations for use in design and construction of shallow
foundations, floor slabs, rigid retaining walls, and pavements.
• Provide this written report summarizing the results of our geotechnical investigation and
recommendations for the project.
2.0 SITE DESCRIPTION
2.1 Site Geology
Based on available geologic mapping' of the area, the site is underlain by Quaternary older alluvium (Coal).
The older alluvium consists of poody consolidated clay, silt, sand and gravel deposited by the Willamette and
McKenzie rivers. This unit includes lahars and tuffs, and is over hundred feet thick in the vicinity of the site.
The older alluvium is underlain by the Oligocene and Eocene Eugene Formation. The Eugene Formation
consists of tan to brown and white where weathered, thin bedded to massive, micaceous, locally tuffaceous
sandstone, siltstone, and minor volcaniclastic conglomerate beds. This unit is locally strongly cemented with
carbonate or iron oxide.
2.2 Site Surface Conditions
The site was bordered by High Banks Road to the north, a vacant grass field (and 52"d Street beyond) to the
east, Highway 126 to the south, and an established industrial property to the west. At the time of our field
investigation, the site was relatively level and was surfaced with short grasses, blackberry brambles, and
some trees. A billboard sign structure was present within the southwest portion of the site. Site layout and
surface conditions at the time of our field investigation are shown on the attached Site Plan (Figure 2) and
Site Photographs (Figure 3).
2.3 Subsurface Conditions
2.3.1 Subsurface Investigation & Laboratory Testing
Our subsurface investigation consisted of six test pits (TP -1 through TP -6) completed on June 9, 2023. The
approximate exploration locations are shown on the Site Plan, attached as Figure 2. In summary, the test
pits were excavated to depths of up to about 10 feet bgs. Details regarding the subsurface investigation, logs
of the explorations, and results of laboratory testing are presented in Appendix A. Subsurface conditions
encountered during our investigation are summarized below.
2.3.2 Subsurface Materials
Logs of the explorations are presented in Appendix A. The following describes each of the subsurface
materials encountered at the site.
Waker, George W. and Duncan, Robert A., 1989, Geologic Map of the Salem 1 degree by 2 degree Quadrangle, Western,
Oregon: U.S. Gedogical Sunrey, Miscellaneous Investigations Map Series, Map 1-1893, scale 1:250 DDD.
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CGT Pmpct Number G2305919
June 21, 2023
Undocumented Poorly Graded Gravel wth Siff and Sand Fill (GP Filll
Undocumented poorly graded gravel fill was encountered at the surface of TP -1 through TP -3.
Undocumented fill refers to materials placed without (available) records of subgrade conditions or evaluation
of compaction. The poorly graded gravel fill was typically brown, dry to moist, angular to rounded, up to
about 2 -inches in diameter, and contained various amounts of silt and sand. This soil extended to depths of
about 1 foot bgs.
Undocumented Elastic Siff Fill (MH Fill)
Underlying the gravel fill in TP -1 and TP -2 was undocumented elastic silt fill. This soil was typically dark
brown to brown with mottling, moist, exhibited medium plasticity, and contained various amounts of rounded
gravel up to 2 inches in diameter. This soil extended to depths of about 2%feet bgs.
Organic Soil (OL )
Encountered at the surface of TP -4 through TP -5 was organic soil (topsoil). This soil was typically brown,
dry, exhibited low plasticity, and contained abundant rootlets. The soil extended to depths of about '/,foot
bgs.
Elastic Silt, Sandy Elastic Silt (MH)
Underlying the undocumented fill in TP -1 through TP -3 and underlying the organic soil in TP -4 and TP -5 was
native elastic silt. This soil ranged from medium stiff to very stiff, was typically brown, moist, exhibited
medium to high plasticity, and contained various amounts of fine-grained sand and subrounded to rounded
gravel up to 1 -inch in diameter. This soil extended to the full depths explored in TP -1 and TP -2, about 10 feet
bgs, and extended to depths of about 3 to 9'/. feet bgs in TP -3 through TP -5.
Poorly Graded Gravel (GP)
Underlying the native silt in TP -3 through TP -5, and underlying the organic soil in TP -6 was native, poorly
graded gravel. This soil was typically medium dense to dense, brown, moist, subrounded to rounded, up to
4 -inches in diameter and contained various amounts of cobbles, no to trace medium plasticity silt and fine- to
coarse-grained sand. This soil extended to the full depths explored in TP -3 through TP -6, up to about 10 feet
bgs.
The native soils encountered during our subsurface investigation were consistent with the lower Clackamas
River terrace deposits described in Section 2.1.
2.3.3 Groundwater
Groundwater seepage was encountered at a depth of about 10 feet bgs within TP -6 on June 9, 2023.
Groundwater was not encountered within the depths explored in the remaining test pits. To determine
approximate regional groundwater levels in the area, we researched well logs available on the Oregon Water
Resources Department (OWRD)2 website for wells located within Section 28, Township 17 South, Range 2
West, Willamette Meridian. Our review indicated that groundwater levels in the area generally ranged from
about 11 to 15 feet bgs. It should be noted groundwater levels vary with local topography. In addition, the
groundwater levels reported on the OWRD logs often reflect the purpose of the well, so water well logs may
only report deeper, confined groundwater, while geotechnical or environmental borings will often report any
' Oregon Water Resources Depadmenl, 2023. Wel Log Records, accessed May 2023, frau OWRD web site:
html/aoos.w d state.or.uslapos/ow/well Ion/.
Carlson Geotechnical Page 6 of 22
Anytime Seff Storage Sprirgf ald
Spingfiefd, Oregon
CGT Propct Number G2305919
Juror 21, 2023
groundwater encountered, including shallow, unconfined groundwater. Therefore, the levels reported on the
OWRD well logs referenced above are considered generally indicative of local water levels and may not
reflect actual groundwater levels at the project site. We anticipate that groundwater levels will fluctuate due
to seasonal and annual variations in precipitation, changes in site utilization, or other factors Additionally, the
on-site, silt is conducive to formation of perched groundwater.
3.0 SEISMIC CONSIDERATIONS
3.1 Seismic Design
Section 1613.2.2 of the 2022 Oregon Structural Specialty Code (2022 OSSC) requires that the determination
of the seismic site class be in accordance with Chapter 20 of the American Society of Civil Engineers
Minimum Design Loads for Buildings and Other Structures (ASCE 7-16). We have assigned the site as Site
Class D ("Stiff Soil") based on geologic mapping and subsurface conditions encountered during our
investigation.
Earthquake ground motion parameters for the site were obtained in accordance with the 2022 OSSC using
the Seismic Hazards by Location calculator on the ATC website3. The site Latitude 44.05762818' North and
Longitude 122.9425914' West were input as the site location. The following table shows the recommended
seismic design parameters for the site.
Table 1 Seismic Ground Motion Values
Pammeter Value
Mapped Acceleration Parameters Spectral Acceleration, 0.2 second (S,) 0.641g
Spectral Acceleration, 1.0 second (Si) 0.3708
Coefficients Site Coefficient 0.2 second (FA) 1.287
(Site Class D) Site Coefficient, 1.0 second (Fv) 1.930
Adjusted MCE Spectral MCE Spectral Acceleration, 0.2 second (S.) 0.825g
Response Parameters MCE Spectral Acceleration, 1.0 second(Sut) 0.714g
Design Spectral Acceleration, 0.2 second(Sps) 0.550g
Design Spectral Response Accelerations
Design Spectral Acceleration, 1.0 second (Spt) 0.4768
Seismic Design Category (Risk Category II) D
Value determined from 2022 OSSC Table 1613.2.3(2).
3.2 Seismic Hazards
3.2.1 Liquefaction
In general, liquefaction occurs when deposits of loose/soft, saturated, cohesionless soils, generally sands
and silts, are subjected to strong earthquake shaking. If these deposits cannot drain quickly enough, pore
water pressures can increase, approaching the value of the overburden pressure. The shear strength of a
cohesionless soil is directly proportional to the effective stress, which is equal to the difference between the
overburden pressure and the pore water pressure. When the pore water pressure increases to the value of
the overburden pressure, the shear strength of the soil approaches zero, and the soil can liquefy. The
'
Applied! Technology Caundl (ATC), 2023. USGS sdsmic design perimeters detemined using'Seismio Hazards by Lcoaean;
aocesed June 2023, font the ATC website httos://hazard s.atcouncil.ora/.
Carlson Geotechnical Page 7 of 22
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CGT Pmpd Number G2305919
June 21, 2023
liquefied soils can undergo rapid consolidation or, if unconfined, can flow as a liquid. Structures supported by
the liquefied soils can experience rapid, excessive settlement, shearing, or even catastrophic failure.
For fine-grained soils, susceptibility to liquefaction is evaluated based on penetration resistance and
plasticity, among other characteristics. Criteria for identifying non -liquefiable, fine-grained soils are constantly
evolving. Current practice to identify non -liquefiable, fine-grained soils is based on moisture content and
plasticity characteristics of the soils'1'8. The susceptibility of sands, gravels, and sand -gravel mixtures to
liquefaction is typically assessed based on penetration resistance, as measured using SPTs, CPTs, or
Becker Hammer Penetration tests (BPTs).
The Oregon Department of Geology and Mineral Industries' Oregon Statewide Geohazards Viewer (H azVU)7
shows a moderate hazard for liquefaction at the site. The Oregon Hazard Explorer for Lifelines Program (O-
HELP)a show a very lav hazard for liquefaction for the site or immediate vicinity due to a M9.0 Cascadia
Subduction Zone earthquake.
Based on their plasticity characteristics and lack of saturated conditions, the native silty soils (MH) are
considered non -liquefiable. Due to their medium dense to better relative density, the native poorly graded
gravels (GP) are not considered liquefiable. Based on experience in the area of the site, we do not anticipate
liquefiable soil conditions exist below those explored as part of this assignment. Notwithstanding the
preceding, if the property owner wishes to further define the risk of liquefaction at the site, a quantitative
liquefaction triggering and settlement analysis could be performed. Such an analysis would require drilled
borings using powered drilling equipment and is outside the scope of this assignment, but could be
performed, upon request, for an additional fee.
3.2.2 Slope Instability
Due to the relatively level topography at and surrounding the site, the risk of slope instability at the site is
considered negligible. The proposed grading includes relatively minimal planned changes in site grades and
is not anticipated to significantly increase this risk.
3.2.3 Surface Rupture
3.2.3.1 Faugino
Although the site is situated in a region of the country with known active faults and historic seismic activity,
no known faults exist on or immediately adjacent to the site. Therefore, the risk of surface rupture at the site
due to faulting is considered negligible.
" Seed, R.B. et al., 2003. Recent Advances in Soil Liquefaction Engineering: A Unified and Consistent Frimevoik, Earthquake
Pngineenng Research Center Repot No. EERC 2993-96.
° Bmy, Jonathan 0., Sando, Roddfo B., st al., 2006. Liquefadion Susceptibility of Fine -Grained Soils, Journal of Geotechnical and
GeoemAronmental Engineering, Volume 132, Issue 9, September 2006.
° Idiiss, I.M., Boulanger, R W., 2008. Soil Liquefaction During Earthquakes, Earthquakes Engineering Research InstAute Monograph
MNO-12,
Oregon Department of Geology and Mineral Industries, 2923. Oregon Statewide Geohazards Viewer, accessed May 2923, from
DOGAMI web site: hdo://w.vv.oreoonoeoloov.om/subrT wrindex.hhn.
° Oregon Slate University College a Engineering, 2923. Oregon Hazard Explorer for Lifelines Program (O -HELP), accessed May
2023, fmrn O -HELP web site: hills://ohelo.oreconsiate.eduli ui-state=dialoo.
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CGT Pr*ct Number G2305919
June 21, 2023
3.2.3.2 Lateral Spread
Surface rupture due to lateral spread can occur on sites underlain by liquefiable soils that are located on or
immediately adjacent to slopes steeper than about 3 degrees (20HAV), and/or adjacent to a free face, such
as a stream bank or the shore of an open body of water. During lateral spread, the materials overlying the
liquefied soils are subject to lateral movement downslope or toward the free face. Given the lack of
liquefiable soils encountered and generally flat nature of the site and immediate vicinity, the risk of surface
rupture due to lateral spread is considered very lowto negligible
4.0 CONCLUSIONS
Based on the results of our field explorations and analyses, the site may be developed as described in
Section 1.1 of this report, provided the recommendations presented in this report are incorporated into the
design and development. Satisfactory subgrade support for planned shallow foundations, retaining walls,
floor slabs, and pavements can be achieved by the native, medium stiff to better, silty soils (MH), the native,
medium dense to dense, gravelly soils (GP), or structural fill that is properly placed and compacted on these
materials during construction. These soils were encountered at depths of 1/4 to 3 feet bgs within our
explorations.
As indicated above, we encountered undocumented fill in test pits TP -1 through TP -3 that extended to
depths of up to about 3 feet bgs. The existing fill materials encountered within those test pits were highly
variable in terms of relative consistency/density. Due to their highly variable consistency/density, it is evident
the existing fill materials were not placed in accordance with typical code requirements for structural fill. The
existing fill materials are not recommended for subgrade support of building foundations, floor slabs, or
pavements due to the inherent risk of (1) uneven subgrade response once loads are applied, and (2)
excessive, long-term, total and differential settlements. Where encountered at design subgrade elevations for
those features, CGT recommends the existing fill materials be removed and replaced with structural fill
placed and compacted in accordance with the recommendations provided in Section 5.4 below. The existing,
inorganic fill materials may be re -used as structural fill at the site as described in Section 5.4.1 of this report.
The near surface silty soils are susceptible to disturbance during wet weather. Trafficability of these soils
may be difficult, and significant damage to the subgrade could occur, if earthwork is undertaken without
proper precautions at times when the exposed soils are more than a few percentage points above optimum
moisture content. In the event that construction occurs during wet weather, CGT recommends that measures
be implemented to protect the fine-grained subgrade in areas of repeated construction traffic and within
foundation excavations. Geotechnical recommendations for wet weather construction are presented in
Section 5.3 of this report.
5.0 RECOMMENDATIONS
The recommendations presented in this report are based on the information provided to us, results of our
field investigation and analyses, laboratory data, and professional judgment. CGT has observed only a small
portion of the pertinent subsurface conditions. The recommendations are based on the assumptions that the
subsurface conditions do not deviate appreciably from those found during the field investigation. CGT should
be consulted for further recommendations if the design of the proposed development changes and/or
variations or undesirable geotechnical conditions are encountered during site development.
Carlson Geotechnical Page 9 of 22
Anytime Setl Storage Springfield
Springfield, Oregon
CGT Project Number G2305919
June 21, 2023
5.1 Site Preparation
5.1.1 Stripping
Existing vegetation, topsoil, rooted soils, and undocumented fill soils (GP -GM Fill, MH Fill) should be
removed from within, and for a minimum 5 -foot margin around, proposed building pad, structural fill, and
pavement areas. Based on the results of our field explorations, topsoil stripping depths are anticipated to be
on the order of A foot bgs. Based on the results of our field explorations, undocumented fill encountered at
the site extended to depths of up to about 3 feet bgs. These materials may be deeper or shallower at
locations away from the completed explorations. The geotechnical engineer's representative should provide
recommendations for actual stripping depths based on observations during site stripping. Stripped surface
vegetation and rooted soils should be transported off-site for disposal, or stockpiled for later use in
landscaped areas. Stripped, inorganic fill materials should be transported off-site for disposal, or may be
stockpiled for later use as structural fill as described in Section 5.4.1 of this report.
5.1.2 Grubbing
Grubbing of shrubs and trees should include the removal of the root mass and roots greater than %inch in
diameter. Grubbed materials should be transported off-site for disposal. Root masses from larger trees may
extend greater than 3 feet bgs. Where root masses are removed, the resulting excavation should be properly
backfilled with structural fill in conformance with Section 5.4 of this report.
5.1.3 Test Pit Backfills
The test pits conducted at the site were loosely backfilled during our field investigation. Where test pits are
located within finalized building, structural fill, or pavement areas, the loose backfill materials should be re -
excavated. The resulting excavations should be backfilled with structural fill in conformance with Section 5.4
of this report.
5.1.4 Existing Utilities & Below -Grade Structures
All existing utilities at the site should be identified prior to excavation. Abandoned utility lines beneath the
new buildings, pavements, and hardscaping features should be completely removed or grouted full. Soft,
loose, or otherwise unsuitable soils encountered in utility trench excavations should be removed and
replaced with structural fill in conformance with Section 5.4 this report. Buried structures (i.e. footings,
foundation walls, retaining walls, slabs -on -grade, tanks, etc.), if encountered during site development, should
be completely removed and replaced with structural fill in conformance with Section 5.4 of this report.
5.1.5 Subgrade Preparation — Building Pads & Pavements
After site preparation as recommended above, but prior to placement of structural fill and/or aggregate base,
the geotechnical engineer's representative should observe the exposed subgrade soils in order to identify
areas of excessive yielding through either proof rolling or probing. Proof rolling of subgrade soils is typically
conducted during dry weather using a fully -loaded, 10- to 12-cubio-yard, tandem -axle, tire -mounted, dump
truck or equivalent weighted water truck. Areas of limited access or that appear too soft or wet to support
proof rolling equipment should be evaluated by probing. During wet weather, subgrade preparation should be
performed in general accordance with the recommendations presented in Section 5.3 of this report. If areas
of soft soil or excessive yielding are identified, the affected material should be over -excavated to firm,
unyielding subgrade, and replaced with imported granular structural fill in conformance with Section 5.4.2 of
this report.
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5.1.6 Erosion Control
Erosion and sedimentation control measures should be employed in accordance with applicable City,
County, and State regulations.
5.2 Temporary Excavations
5.2.1 Overview
Conventional earthmoving equipment in proper working condition should be capable of making necessary
excavations for the anticipated site cuts as described earlier in this report. All excavations should be in
accordance with applicable OSHA and state regulations. It is the contractor's responsibility to select the
excavation methods, to monitor site excavations for safety, and to provide any shoring required to protect
personnel and adjacent improvements. A "competent person,' as defined by OR -OSHA, should be on-site
during construction in accordance with regulations presented by OR -OSHA. CGT's current role on the
project does not include review or oversight of excavation safety.
5.2.2 OSHA Soil Type
For use in the planning and construction of temporary excavations up to 10 feet in depth, an OSHA soil type
of "B" may be used for the silty soils (MH). Similarly, an OSHA soil type "C" should be used for the coarse-
grained soils (GP) encountered at depth at the site.
5.2.3 Utility Trenches
Temporary trench cuts should stand near vertical to depths of approximately 4 feet in the native, silty soils
(MH) and gravelly soils (GP) encountered near the surface of the site. If groundwater seepage undermines
the stability of the trench, or if sidewall caving is observed during excavation, the sidewalls should be
flattened or shored. Depending on the time of year trench excavations occur, trench dewatering may be
required in order to maintain dry working conditions. If groundwater is encountered, we recommend placing
trench stabilization material at the base of the excavations. Trench stabilization material should be in
conformance with Section 5.4.3.
5.2.4 Excavations Near Foundations
Excavations near footings should not extend within a 1 horizontal to 1 vertical (1 H:1 V) plane projected out
and down from the outside, bottom edge of the footings. In the event excavation needs to extend bel ow the
referenced plane, temporary shoring of the excavation and/or underpinning of the subject footing may be
required. The geotechnical engineer should be consulted to review proposed excavation plans for this design
case to provide specific recommendations.
5.3 Wet Weather Considerations
For planning purposes, the wet season should be considered to extend from late September to late June. It
is our experience that dry weatherworking conditions should prevail between early July and mid-September.
Notwithstanding the above, soil conditions should be evaluated in the field by the geotechnical engineer's
representative at the initial stage of site preparation to determine whether the recommendations within this
section should be incorporated into construction.
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5.3.1 Overview
Due to their fines content, the silty soils (MH) are susceptible to disturbance during wet weather. Traffcability
of these soils may be difficult, and significant damage to subgrade soils could occur, if earthwork is
undertaken without proper precautions at times when the exposed soils are more than a few percentage
points above optimum moisture content. For wet weather construction, site preparation activities may need to
be accomplished using track -mounted equipment, loading removed material onto trucks supported on
granular haul roads, or other methods to limit soil disturbance. The geotechnical engineer's representative
should evaluate the subgrade during excavation by probing rather than proof rolling. Soils that have been
disturbed during site preparation activities, or soft or loose areas identified during probing, should be over -
excavated to firm, unyielding subgrade, and replaced with imported granular structural fill in conformance
with Section 5.4.2.
5.3.2 Geotextile Seoaration Fabric
We recommend a geotextile separation fabric be placed to serve as a barrier between the prepared
subgrade and granular fill/base rock in areas of repeated or heavy construction traffic. The geotextile fabric
should meet the requirements presented in the current Oregon Department of Transportation (ODOT)
Standard Specification for Construction (ODOT SSC), Section 02320.
5.3.3 Granular Working Surfaces (Haul Roads & Staging Areas)
Haul roads subjected to repeated heavy, tire -mounted, construction traffic (e.g. dump trucks, concrete trucks,
etc.) will require a minimum of 18 inches of imported granular material. For light staging areas, 12 inches of
imported granular material is typically sufficient. Additional granular material, geo-grid reinforcement, or
cement amendment may be recommended based on site conditions and/or loading at the time of
construction. The imported granular material should be in conformance with Section 5.4.2 and have less than
5 percent material passing the U.S. Standard No. 200 Sieve. The prepared subgrade should be covered with
geotextile fabric (Section 5.3.2) prior to placement of the imported granular material. The imported granular
material should be placed in a single lift (up to 24 inches deep) and compacted using a smooth -drum, non -
vibratory roller until well -keyed.
5.3.4 Cement Amendment
It is sometimes less costly to amend near -surface, moisture -sensitive, fine-grained soils with Portland
cement than to remove and replace those soils with imported granular material. Successful use of soil
cement amendment depends on use of correct techniques and equipment, soil moisture content, and the
amount of cement added to the subgrade (mix design). We anticipate the on-site native silty soils (MH) are
conducive for cement amendment due to their generally medium plasticity and experience with similar soils.
The recommended percentage of cement is based on soil moisture contents at the time the work is
performed. Based on our experience, 3 percent cement by weight of dry soil can generally be used when the
soil moisture content does not exceed approximately 20 percent. If the soil moisture content is in the range of
25 to 35 percent, 4 to 6 percent by weight of dry soil is recommended. It is difficult to accurately predict field
performance due to the variability in soil response to cement amendment. The amount of cement added to
the soil may need to be adjusted based on field observations and performance.
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If cement amendment is considered, we recommend additional sampling, laboratory testing, and a mix
design be performed to determine the level of improvement in engineering properties (strength, stiffness) of
the on-site soils when blended with Portland cement. We recommend project scheduling allowfor a minimum
of 4weeks for this testing and design to be completed, prior to initiating cement amendment.
5.3.5 Footing Subgrade Protection
A minimum of 3 inches of imported granular material (crushed rock) is recommended to protect fine-grained
(silty), footing subgrades from foot traffic during inclement weather. The imported granular material should be
in conformance with Section 5.4.2. The maximum particle size should be limited to 1 inch. The imported
granular material should be placed in one lift over the prepared, undisturbed subgrade, and compacted using
non -vibratory equipment until well keyed.
Surface water should not be allowed to collect in footing excavations. The excavations should be draped
and/or provided with sumps to preclude water accumulation during inclement weather.
5.4 Structural Fill
The geotechnical engineer should be provided the opportunity to review all materials considered for use as
structural fill (prior to placement). Samples of the proposed fill materials should be submitted to the
geotechnical engineer a minimum of 5 business days prior their use on sites. The geotechnical engineer's
representative should be contacted to evaluate compaction of structural fill as the material is being placed.
Evaluation of compaction may take the form of in-place density tests and/or proof roll tests with suitable
equipment. Structural fill should be evaluated at intervals not exceeding every 2 vertical feet as the fill is
being placed.
5.4.1 On -Site Soils — General Use
5.4.1.1 Sily Soils (MH. MH Fill)
Re -use of these soils as structural fill may be difficult because these soils are sensitive to small changes in
moisture content and are difficult, if not impossible, to adequately compact during wet weather. We anticipate
the moisture content of these soils will be higher than the optimum moisture content for satisfactory
compaction. Therefore, moisture conditioning (drying) should be expected in order to achieve adequate
compaction. If used as structural fill, these soils should be free of organic matter, debris, and particles larger
than 4 inches. When used as structural fill, these soils should be placed in lifts with a maximum pre -
compaction thickness of about 8 inches at moisture contents within —1 and +3 percent of optimum, and
compacted to not less than 92 percent of the material's maximum dry density, as determined in general
accordance with ASTM D1557 (Modified Proctor).
5.4.1.2 Poorly Graded Grevels(GP. GP -GM Fill)
Re -use of the on-site, relatively clean, gravelly soils as structural fill is feasible, provided the materials are
kept clean of organics, debris, and particles larger than 4 inches in diameter. Re -use of the on-site native
gravels will likely require processing (removal) of large cobbles and should be factored. If reused as
structural fill, these materials should be prepared in general accordance with Section 5.4.2.
If the on-site materials cannot be properly moisture -conditioned and/or processed, we recommend using
imported granular material for structural fill.
' laborelory testing for moisture density relationship (Proctor) is required. Testsfrgradationmayberequired.
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5.4.2 Imported Granular Structural Fill —General Use
Imported granular structural fill should consist of angular pit or quarry run rock, crushed rock, or crushed
gravel that is fairly well graded between coarse and fine particle sizes. The granular fill should contain no
organic matter, debris, or particles larger than 4 inches, and have less than 5 percent material passing the
U.S. Standard No. 200 Sieve. For fine -grading purposes, the maximum particle size should be limited to 1%
inches. The percentage of fines can be increased to 12 percent of the material passing the U.S. Standard
No. 200 Sieve if placed during dry weather, and provided the fill material is moisture -conditioned, as
necessary, for proper compaction. Imported granular fill material should be placed in lifts with a maximum
thickness of about 12 inches, and compacted to not less than 95 percent of the material's maximum dry
density, as determined in general accordance with ASTM D1557 (Modified Proctor). Proper moisture
conditioning and the use ofvibratory equipment will facilitate compaction of these materials.
Granular fill materials with high percentages of particle sizes in excess of 1^/: inches are considered non -
moisture -density testable materials. As an alternative to conventional density testing, compaction of these
materials should be evaluated by proof roll test observation (deflection tests), where accepted by the
geotechnical engineer.
5.4.3 Trench Base Stabilization Material
If groundwater is present at the base of utility excavations, trench base stabilization material should be
placed. Trench base stabilization material should consist of a minimum of 1 foot of well -graded granular
material with a maximum particle size of 4 inches and less than 5 percent material passing the U.S. Standard
No. 4 Sieve. The material should be free of organic matter and other deleterious material, placed in one lift,
and compacted until well -keyed.
5.4.4 Trench Backfill Material
Trench backfill for the utility pipe base and pipe zone should consist of granular material as recommended by
the utility pipe manufacturer. Trench backfill above the pipe zone should consist of well -graded granular
material containing no organic matter or debris, have a maximum particle size of/. inch, and have less than
8 percent material passing the U.S. Standard No. 200 Sieve. As a guideline, trench backfill should be placed
in maximum 12 -inch -thick lifts. The earthwork contractor may elect to use alternative lift thicknesses based
on their experience with specific equipment and fill material conditions during construction in order to achieve
the required compaction. The following table presents recommended relative compaction percentages for
utility trench backfill.
Table 2 Utility Trench Backfill Compaction Recommendations
Backfill Zone Recommended Minimum Relative Compaction
Structural Areas' Landscaping Areas
90%ASTM D1557 or pipe 85%ASTM D1557 or pipe
Pipe Base and Within Pipe Zone manufacturer's recommendation manufacturer's recommendation
Above Pipe Zone 92%ASTM D1557 88%ASTM D1557
Within 3 Feet of Design Subgrade 95%ASTM D1557 90%ASTM D1557
+ Includes proposed buildings, pavement areas, structural fill areas, exterior hardscaping, etc.
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5.4.5 Controlled Low -Strength Material (CLSM)
CLSM is a self -compacting, cementitious material that is typically considered when backfilling localized
areas. CLSM is sometimes refened to as "controlled density fill" or CDF. Due to its flowable characteristics,
CLSM typically can be placed in restncted-access excavations where placing and compacting fill is difficult. If
chosen for use at this site, we recommend the CLSM be in conformance with Section 00442 of the most
recent, ODOT SSC. The geotechnical engineers representative should observe placement of the CLSM and
obtain samples for compression testing in accordance with ASTM D4832. As a guideline, for each day's
placement, two compressive strength specimens from the same CLSM sample should be tested. The results
of the two individual compressive strength tests should be averaged to obtain the reported 28 -day
compressive strength. If CLSM is considered for use on this site, please contact the geotechnical engineer
for site-specific and application-specific recommendations.
5.5 Shallow Foundations
5.5.1 Subgrade Preparation
Satisfactory subgrade support for shallow foundations can be obtained from the native, medium stiff to
better, silty soils (MH), the native, medium dense to dense, gravelly soils (GP), or new structural fill that is
properly placed and compacted on these materials during construction. The geotechnical engineer's
representative should be contacted to observe subgrade conditions prior to placement of forms,
reinforcement steel, or granular backfill (if required). If soft, loose, or otherwise unsuitable soils are
encountered, they should be over -excavated as recommended by the geotechnical representative at the time
of construction. The resulting over -excavation should be brought back to grade with imported granular
structural fill in conformance with Section 5.4.2. The maximum particle size of over -excavation backfill should
be limited to 1 V, inches. All granular pads for footings should be constructed a minimum of 6 inches wider on
each side of the footing for every vertical foot of over -excavation.
5.5.2 Minimum Footing Width & Embedment
Minimum footing widths should be in conformance with the current OSSC. As a guideline, CGT recommends
individual spread footings have a minimum width of 24 inches. For one- to two-story, light -framed buildings,
we recommend continuous wall footings have a minimum width of 12 and 15 inches, respectively. All
footings should be founded at least 18 inches belowthe lowest, permanent adjacent grade to develop lateral
capacity and for frost protection.
5.5.3 Bearino Pressure & Settlement
Footings founded as recommended above should be proportioned for a maximum allowable soil bearing
pressure of 2,500 pounds per square foot (psf). This bearing pressure is a net bearing pressure, applies to
the total of dead and long-term live loads, and may be increased by one-third when considering seismic or
wind loads. For foundations founded as recommended above, total settlement of foundations is anticipated
to be less than 1 inch. Differential settlements between adjacent columns and/or bearing walls should not
exceed V, inch. If an increased allowable soil bearing pressure is desired, the geotechnical engineer should
be consulted.
5.5.4 Lateral Capacity
A maximum passive (equivalent fluid) earth pressure of 150 pounds per cubic foot (pcf) is recommended for
design of footings cast neat into excavations in suitable native soil or confined by imported granular structural
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fill that is properly placed and compacted during construction. The recommended earth pressure was
computed using a factor of safety of 1%, which is appropriate due to the amount of movement required to
develop full passive resistance. In order to develop the above capacity, the following should be understood:
1. Concrete must be poured neat in excavations or the foundations must be backfilled with imported
granular structural fill,
2. The adjacent grade must be level,
3. The static ground water level must remain below the base of the footings throughout the year.
4. Adjacent floor slabs, pavements, or the upper 12-inch-depth of adjacent, unpaved areas should not be
considered when calculating passive resistance.
An ultimate coefficient of friction equal to 0.35 may be used when calculating resistance to sliding for footings
founded on the native silty soils described above. An ultimate coefficient of friction equal to 0.45 may be
used when calculating resistance to sliding for footings founded on the native coarse-grained soils (GP), or
on a minimum of 6 inches of imported granular structural fill (crushed rock) that is properly placed and
compacted during construction.
5.5.5 Subsurface Drainage
Recognizing the presence of fine-grained (silty) soils (MH) encountered near-surface within the majority of
the site, we recommend placing foundation drains at the exterior, base elevations of perimeter continuous
wall footings that are founded on these soils. Foundation drains should consist of a minimum 4-inch
diameter, perforated, PVC drainpipe wrapped with a non-woven geotextile filter fabric. The drains should be
backfilled with a minimum of 2 cubic feet of open graded drain rock per lineal foot of pipe. The drain rock
should also be encased in a geotextile fabric in order to provide separation from the surrounding fine-grained
soils. Foundation drains should be positively sloped and should outlet to a suitable discharge point. The
geotechnical engineer's representative should observe the drains prior to backfilling. Roof drains should not
be tied into foundation drains.
5.6 Rigid Retaining Walls
5.6.1 Footings
Retaining wall footings should be designed and constructed in conformance with the recommendations
presented in Section 5.5, as applicable.
5.6.2 Wall Drains
We recommend placing retaining wall drains at the base elevation of the heel of retaining wall footings.
Retaining wall drains should consist of a minimum 4-inch-diameter, perforated, HDPE (High Density
Polyethylene) drainpipe wrapped with a non-woven geotextile filter fabric. The drains should be backfilled
with a minimum of 2 cubic feet of open graded drain rock per lineal foot of pipe. The drain rock should be
encased in a geotextile fabric in order to provide separation from the surrounding soils. Retaining wall drains
should be positively sloped and should outlet to a suitable discharge point. The geotechnical engineer's
representative should be contacted to observe the drains prior to backfilling. Roof or area drains should not
be tied into retaining wall drains.
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5.6.3 Wall Backfill
Retaining walls should be backfilled with imported granular structural fill in conformance with Section 5.4.2
and contain less than 5 percent passing the U.S. Standard No. 200 Sieve. The backfill should be compacted
to a minimum of 90 percent of the material's maximum dry density as determined in general accordance with
ASTM D1557 (Modified Proctor). When placing fill behind walls, care must be taken to minimize undue
lateral loads on the walls. Heavy compaction equipment should be kept at least "H" feet from the back of the
walls, where "H" is the height of the wall. Light mechanical or hand tamping equipment should be used for
compaction of backfill materials within "H" feet of the back of the walls.
5.6.4 Desion Parameters & Limitations
For rigid retaining walls founded, backfilled, and drained as recommended above, the following table
presents parameters recommended for design.
Table 3 Design Parameters for Rigid Retaining Walls
Static
Seismic
Surcharge from
Modeled Backfill Equivalent
Equivalent
Uniform Load, q,
Retaining Wall Condition
Condition Fluid
Fluid Pressure
Acting on Backfill
Pressure (SA)'
(SAE) r1
Behind Retaining Wall
Not Restrained from Rotation Level (i=0) 28 pcf 36 pcf 0.22q
Restmined from Rotation Level (i=0) 50 pcf 50 pcf 0.38`q
Refer to the attached Figure 4 for a graphical representation of static and seismic loading conditions. Seismic resultant
force ads at 0.6H above the base of the wall.
' Seismic (dynamic) lateral loads were computed using the Mononobe-Okabe Equation as presented in the 1997 Federal
Highway Administration (FHWA) design manual. Static and seismic equivalent Fluid pressures are not additive.
The above design recommendations are based on the assumptions that:
The walls consist of concrete cantilevered retaining walls (p = 0 and 5 = 24 degrees, see Figure 4).
The walls are 10 feet or less in height.
The backfill is drained and consists of imported granular structural fill 38 degrees).
No point, line, or strip load surcharges are imposed behind the walls.
The grade behind the wall is level, or sloping down and away from the wall, for a distance of 10 feet or
more from the wall.
The grade in front of the walls is level or ascending for a distance of at least 5 feet from the wall.
Re-evaluation of our recommendations will be required if the retaining wall design criteria for the project vary
from these assumptions.
5.6.5 Surcharge Loads
Where present, surcharges from adjacent site features (i.e. buildings, slabs, pavements, etc.) should be
evaluated in design of retaining walls at the site. Methods for calculating lateral pressures on rigid retaining
walls from strip, line, and vertical point loads are presented on the attached Figure 5.
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67► Jflz-T&IFI-)
5.7.1 Subarade Preparation
Satisfactory subgrade support for slabs constructed on grade, supporting up to 150 psf area loading, can be
obtained from the native, medium stiff to better, silty soils (MH), the native, medium dense to dense, gravelly
soils (GP), or newstructural fill that is properly placed and compacted on these materials during construction.
The geotechnical engineer's representative should observe floor slab subgrade soils to evaluate surface
consistencies. If soft, loose, or otherwise unsuitable soils are encountered, they should be over -excavated as
recommended by the CGT geotechnical representative at the time of construction. The resulting over -
excavation should be brought back to grade with imported granular structural fill as described in
Section 5.4.2.
5.7.2 Crushed Rock Base
Concrete floor slabs should be supported on a minimum 6 -inch -thick layer of crushed rock (base rock).. Floor
slab base rock should consist of well -graded granular material (crushed rock) containing no organic matter or
debris, have a maximum particle size of/. inch, and have less than 5 percent material passing the U.S.
Standard No. 200 Sieve. Floor slab base rock should be placed in one lift and compacted to not less than
95 percent of the material's maximum dry density as determined in general accordance with ASTM D1557
(Modified Proctor). We recommend "choking" the surface of the base rock with sand just prior to concrete
placement. Choking means the voids between the largest aggregate particles are filled with sand, but does
not provide a layer of sand above the base rock. Choking the base rock surface reduces the lateral restraint
on the bottom of the concrete during curing. Choking the base rock also reduces punctures in vapor
retarding membranes due to foot traffic where such membranes are used.
5.7.3 Design Considerations
For floor slabs constructed as recommended, an effective modulus of subgrade reaction of 150 pounds per
cubic inch (pci) is recommended for the design of the floor slab. A higher effective modulus of subgrade
reaction can be obtained by increasing the base rock thickness. Please contact the geotechnical engineer for
additional recommendations if a higher modulus is desired. Floor slabs constructed as recommended will
likely settle less than %inch. For general floor slab construction, slabs should be jointed around columns and
walls to permit slabs and foundations to settle differentially.
5.7.4 Subgrade Moisture Considerations
Liquid moisture and moisture vapor should be expected at the subgrade surface. The recommended crushed
rock base is anticipated to provide protection against liquid moisture. Where moisture vapor emission
through the slab must be minimized, e.g. impervious floor coverings, storage of moisture sensitive materials
directly on the slab surface, etc., a vapor retarding membrane or vapor barrier below the slab should be
considered. Factors such as cost, special considerations for construction, floor coverings, and end use
suggest that the decision regarding a vapor retarding membrane or vapor barrier be made by the architect
and owner.
If a vapor retarder or vapor barrier is placed below the slab, its location should be based on current American
Concrete Institute (ACI) guidelines, ACI 302 Guide for Concrete Floor and Slab Construction. In some cases,
this indicates placement of concrete directly on the vapor retarder or barrier. Please note that the placement
of concrete directly on impervious membranes increases the risk of plastic shrinkage cracking and slab
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curling in the concrete. Construction practices to reduce or eliminate such risk, as described in ACI 302,
should be employed during concrete placement.
5.8 Is"ements
5.8.1 Subarade Preparation
Satisfactory subgrade support for pavements can be obtained from the native, medium stiff to better, silty
soils (MH), the native, medium dense to dense, gravelly soils (GP), or new structural fill that is properly
placed and compacted on these materials during construction. Pavement subgrade preparation should be
performed in general accordance with the recommendations presented in Section 5.1.6 of the referenced
report. Subgrade surfaces should be crowned (or sloped) for proper drainage in accordance with
specifications provided by the project civil engineer.
5.8.2 Traffic Classifications
Recognizing that traffic data has not been provided, CGT has considered four levels of traffic demand for
review and design of pavement sections. We modeled the following four design cases (traffic levels)
developed from the Asphalt Pavement Association of Oregon (APAO):
• APAO Level l (Very Ligtt): This design case considers typical average daily truck traffic (ADTT) of 1 per
day over 20 years. Among others, examples under this loading consist of passenger car parking stalls,
residential driveways, and seasonal recreational roads.
• APAO Level 11 (Ligtt): This design case considers typical ADTT of 2 to 7 per day over 20 years.
Examples under this loading consist of residential streets and parking lots of less than 500 stalls.
• APAO Level 111 (Low Moderate): This design case considers typical ADTT of 7 to 14 per day over 20
years. Among others, examples under this loading consist of urban minor collector streets and parking
lots with more than 500 stalls.
• APAO Level IV (Moderate): This design case considers typical ADTT of 14 to 35 per day over 20 years.
Among others, examples under this loading consist of urban minor arterial streets and residential streets
with bus routes.
We recommend the owner and design team review the traffic levels presented above and select those that
most accurately represent anticipated daily truck traffic for select new pavements.
5.8.3 Input Parameters
Design of the asphalt concrete (AC) pavement sections presented below were based on the parameters
presented in the following table, the American Association of State Highway and Transportation Officials
(AASHTO) 1993 "Design of Pavement Structures' manual, and pavement design manuals presented by
APAO and ODOT". If any of the items listed need revision, please contact us and we will reassess the
provided design sections.
1. Oregon Department of Transportation (ODOT) Pavement Design Guide, January 2019.
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Table 4 Input Parameters Used in AC Pavement Design
Input Parameter
Design Valuer
Input Parameter
Design Value'
Pavement Design Life
20 years
Resilient
Modulus
Silty Soils (MH)4
Crushed Aggregate Bases
5,000 psi
20,000 psi
Annual Percent Growth 0 percent
Serviceability
4.2 initial, 2.5 terminal
Structural
Coefficients
Crushed Aggregate Base
Asphalt
0.10
0.42
Reliability2 75 percent
Standard Deviation
0.49
Vehicle Traffics
(range in
ESALs)
APAO Level I (Very Light)
APAO Level 11 (Light)
APAO Level III (Low Moderate)
APAO Level IV (Moderate)
Up to 10,000
Up to 50,000
Up to 100,000
Up to 250,000
Drainage Factors 10
--- --
--- --
I Ifairy ofthe above parameters are incorrect, please contact us so thatwe may revise our recommendations, ifwarranted.
s Value based on guidelines presented in Sectan 5.3 of the 2019 ODOT Pavement Design Guide and APAO manual.
s Assumes good drainage away from pavement, base, and subgrade is achieved by proper crowning of subgrades.
4 Values based on experience with similar soils prepared as recommended in this report
s ESAL = Total 18 -Kip equivalent single ale had. Traffic levels taken from Table 3.1 of APAO manual. If an increased traffic load is
estimated, please contact us so that we may refine the traffic loading and revise our recammendabons, ifwarramed.
5.8.4 Recommended Minimum Sections
The following table presents the minimum AC pavement sections for various traffic loads indicated in the
preceding table, based on the referenced AASHTO procedures.
Table 5 Recommended Minimum Asphalt Concrete Pavement Sections
Matarlal APAO Traffic Loading
Laval Level 11 Level III Laval IV
Asphalt Pawment(lnches) 3 3% 4 41A
Crushed Aggregate Base (inches)r a 10 10 11
Subgrade Sails Prepared in conformance with Section 5.1.5 of this report
Nates: Thicknesses shown assume drvweathercanstruction. A thickergranular subbase section maybe required in wet conditions in
order to support construction traffic and pratedthe subgrade. Refer to Secfian 5.3 of the main report for addifianal discussion
5.8.5 AC Pavement Materials
We recommend pavement aggregate base consist of dense -graded aggregate in conformance with Section
02630.10 of the most recent State of Oregon, Standard Specifications for Highway Construction (ODOT
SSC), with the following additional considerations. We recommend the material consist of crushed rock or
gravel, have a maximum particle size of 1% inches, and have less than 5 percent material passing the U.S.
Standard No. 200 Sieve. Aggregate base should be compacted to not less than 95 percent of the material's
maximum dry density as determined in general accordance with ASTM D1557 (Modified Proctor).
We recommend asphalt pavement consist of Level 2, %inch, dense -graded HMAC in conformance with the
most recent ODOT SSC. Asphalt pavement 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).
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5.9 Additional Considerations
5.9.1 Drainage
Subsurface drains should be connected to the nearest storm drain, on-site infiltration system (to be designed
by others) or other suitable discharge point. Paved surfaces and grading near or adjacent to the buildings
should be sloped to drain away from the buildings. Surface water from paved surfaces and open spaces
should be collected and routed to a suitable discharge point. Surface water should not be directed into
foundation drains or retaining wall drains.
5.9.2 Expansive Potential
Moderate to high plasticity elastic silt (MH) was encountered within TP -1 through TP -5, and is anticipated to
be moderately susceptible to potential shank -swell behavior. Provided the recommendations presented
above are followed during construction, and perimeter foundation and retaining wall drains are installed as
recommended above, the potential for expansive behavior of this soil to occur following construction of the
buildings should be mitigated to an acceptable level.
6.0 RECOMMENDED ADDITIONAL SERVICES
6.1 Design Review
Geotechnical design review is of paramount importance. We recommend the geotechnical design review
take place prior to releasing bid packets to contractors.
6.2 Observation of Construction
Satisfactory earthwork, foundation, floor slab, and pavement performance depends to a large degree on the
quality of construction. Sufficient observation of the contractor's activities is a key part of determining that the
work is completed in accordance with the construction drawings and specifications. Subsurface conditions
observed during construction should be compared with those encountered during subsurface explorations,
and recognition of changed conditions often requires experience. We recommend that qualified personnel
visit the site with sufficient frequencyto detect whether subsurface conditions change significantly from those
observed to date and anticipated in this report. We recommend geotechnical engineer's representative
attend a pre -construction meeting coordinated by the contractor and/or developer. The project geotechnical
engineer's representative should provide observations and/or testing of at least the following earthwork
elements during construction:
• Site Stripping & Grubbing
• Subgrade Preparation for Shallow Foundations, Retaining Walls, Structural Fills, Floor Slabs, and
Pavements
• Compaction of Structural Fill, Retaining Wall Backfill, and Utility Trench Backfill
• Compaction of Base Rock for Floor Slabs and Pavements
• Compaction of Asphalt Concrete for Pavements
It is imperative that the owner and/or contractor request earthwork observations and testing at a frequency
sufficient to allow the geotechnical engineer to provide a final letter of compliance for the earthwork activities.
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MA 41.I I k CA d1-1" K
We have prepared this report for use by the owner/developer and other members of the design and
construction team for the proposed development. The opinions and recommendations contained within this
report are forwarded to assist in the planning and design process and are not intended to be, nor should they
be construed as, awarranty of subsurface conditions.
We have made observations based on our explorations that indicate the soil conditions at only those specific
locations and only to the depths penetrated. These observations do not necessarily reflect soil types, strata
thickness, or water level variations that may exist between or away from our explorations. If subsurface
conditions vary from those encountered in our site explorations, CGT should be alerted to the change in
conditions so that we may provide additional geotechnical recommendations, if necessary. Observation by
experienced geotechnical personnel should be considered an integral part ofthe construction process.
The owner/developer is responsible for ensuring that the project designers and contractors implement our
recommendations. When the design has been finalized, prior to releasing bid packets to contractors, we
recommend that the design drawings and specifications be reviewed by our firm to see that our
recommendations have been interpreted and implemented as intended. If design changes are made, we
request that we be retained to review our conclusions and recommendations and to provide a written
modification or verification. Design review and construction phase testing and observation services are
beyond the scope of our current assignment, but will be provided for an additional fee.
The scope of our services does not include services related to construction safety precautions, and our
recommendations are not intended to direct the contractor's methods, techniques, sequences, or
procedures, except as specifically described in our report for consideration in design.
Geotechnical engineering and the geologic sciences are characterized by a degree of uncertainty.
Professional judgments presented in this report are based on our understanding of the proposed
construction, familiarity with similar projects in the area, and on general experience. Within the limitations of
scope, schedule, and budget, our services have been executed in accordance with the generally accepted
practices in this area at the time this report was prepared; no warranty, expressed or implied, is made. This
report is subject to review and should not be relied upon after a period of three years.
Carlson Geotechnical Page 22 of 22
ANYTIME SELF STORAGE- SPRINGFIELD, OREGON FIGURE 1
Project Number G2305919 Site Location
-
s
r y
1 ,
USGS Topographic base map created with The National Map, 2023, at Latitude: 44.05762818' North
T� hfps://viewer.nationalmap.gm/adwnced-Nemd Longitude: -122.9425914' West
® 1 Inch = 2,000 feet
wuaazw
o�a�. Township 17 South, Range 2 West, Section 28, Willamette Meridian 0 2000 4000
ANYTIME SELF STORAGE - SPRINGFIELD, OREGON
FIGURE 2
Project Number G2305919
Site Plan
3
„
a
�..�
„TP/IT-4
— 2
Sq
1
9
..
TPAT-
6
,
h
LEGEND 1 Inch = 50 Feet
SPIT-�
Test pit exploration with Infiltration Testing. _ _ _ 0 50 100
I I Approximate property line, as NOTES: 2021 aerial image from ESRI World Imagery Basemap,
osc Q Orientation of site photographs shown on Figure 3 I —/ understood by CGT 2023.Two4teotekration contours(NAVDaa) based on 2016
DOGAMI lidar data, processed in OGIS 3.2.2 and ESRI ArcGIS
o,.a�MT Pro 2.5.0. Locations noted are approximate.
ANYTIME SELF STORAGE - SPRINGFIELD, OREGON FIGURE 3
Project Number G2305919 Site Photographs
Photograph 1
Photograph 2
Photograph 3
Photograph 4
See Figure 2 for approximate photograph locations and drections. Photographs were taken at the fime of our fieMuork.
ANYTIME SELF STORAGE - SPRINGFIELD, OREGON FIGURE 4
Project Number G2305919 Retaining Walls
STATIC LOADING CONDITIONS
-- -------------v--- --PACUSA)(H)
H
�
SEISMIC LOADING CONDITIONS
0.6H____
y � i
J,
SA =Active lateral equivalent fluid pressure (IhAt)*
SbA=Active lateral earth pressure (static) at the bottom of wall (lbfl[�
SAE =AcWetotal (static+seismic) equivalent fluid pressure (lb/ r
= Slope of bacldill, relative to horizontal (degrees)"
3 = Slope of back of wall, relative to vertical (degrees)"
��// i
('A)(SAE- SA)(H)
PA = CA)(S�(H)
Sm = (S�(H)
PA = Static active thrustforce acting at H/3 from bottom of retaining wall (INft)
PE = Dynamic active thrustfarce acting at 0.6H from bottom of retaining wall (lbq
S= Angle from normal of back ofwall(degrees). Based on friction developing
behveen wall and backfiir*
Notes
16�1G7�T�y 1. Uniform pressure distribution of seismic loading is based on empirical evaluations [Sherif at al, 1982 and Whitman, 1990].
2. Placement of seismic resultant force at 0.6H is based on wall behavior and model test results [Whitman, 1990].
sm cm -e so
ANYTIME SELF STORAGE - SPRINGFIELD, OREGON I FIGURE 5
Project Number G2305919 Retaining Wall Surcharge
STRIP LOAD PARALLEL TO WALL' LINE LOAD PARALLEL TO WALL2
[<—X=m H
Ct Strip Load, q
Line Load, OL
Z=nH Form <0.4
R aL 0.2n
ah ah ah H (0.16+n2)2
H H
For no > 0.4
GIS 1.28m2n
.h— (2.)] ah H (m2+n2)2
H
VERTICAL POINT LOAD2
All
�X=mH---Cd
Point Load, 0p
ah
For m < 0.4
0p 0.2Bn2
ah H2 (0.16+n2)3
Form > 0.4
Olp 1.77m2n2
ah H2 (m2+n2)3
Section A- A
ah 0p
B
dh
o—X=mH-0I
dh = ah cost (1.1 0)
Notes: 1. Das, Principles afGeatechnical Engineering, 1990 Edition.
rT,y 2. NAVFAC Design Manual 7.06.
sm cm-ees°
Refer to the referenced design manuals for additional guidance. Contact CGT inhere are any questions With modeling surcharge loads.
Carlson Geotechnical Bend Office (541)330-9155Gp RL`S0
A division of Carlson Testing, Inc. Eugene Office (541)345-0289
Phone: (503) 601-8250 Salem Office (503)589-1252
www.carlsontes[ino.cam
Tigard Office (503) 684-3460
Appendix A: Subsurface Investigation and
Laboratory Testing
Anytime Self Storage Springfield
High Banks Road
Springfield, Oregon
CGT Project Number G2305919
June 21, 2023
Prepared For.
Brandon Bennett
Signal Ventures
2538 NE Division Street
Bend, Oregon 97703
Prepared by
Carlson Geotechnical
ExplorationKey.....................................................................................................................................
Figure Al
SoilClassification..................................................................................................................................
Figure A2
ExplorationLogs.........................................................................................................................Figures
A3—A8
Office: 18270 SW Boones FerryRoad, Suite 6, Durham, Oregon 97224
Mailing: P.O. Box 230997, Tigard, Oregon 97281
Appendix A: Subsurface Investigation and Laboratory Testing
Anytime Seff Storage Springfield
Spnngfieid, Oregon
CGT Pr*ct Number G2305919
June 21, 2023
A.1.0 SUBSURFACE INVESTIGATION
Our field investigation consisted of six test pits completed at the site on June 9, 2023. The exploration
locations are shown on the Site Plan, attached to the geotechnical report as Figure 2. The exploration
locations shown therein were determined based on measurements from existing site features (property
corners, etc.) and are approximate. Surface elevations indicated on the logs were estimated based on the
topographic contours (by others) shown on the referenced Site Plan and are approximate. The attached
figures detail the exploration methods (Figure Al), soil classification criteria (Figure A2), and present detailed
logs of the explorations (Figures A3 through A8), as discussed below.
A.1.1 Test Pits
CGT observed the excavation of six test pits (TP -1 through TP -6) at the site to depths of about 5 to 10 feet
bgs. The test pits were excavated using a Bobcat 341 mini -excavator provided and operated by our
excavation subcontractor, Doug Shepherd's Dirtworks of Keizer, Oregon. The test pits were loosely
backfilled with the excavated materials upon completion.
A.1.2 In -Situ Testing
A.1.2.1 Pocket Penetrometer Tests
Pocket penetrometer readings were generally taken at approximate !/,foot intervals in the upper four feet of
each test pit. The pocket penetrometer is a hand-held instrument that provides an approximation of the
unconfined compressive strength of cohesive, fine-grained soils. The correlation between pocket
penetrometer readings and the consistency of cohesive, fine-grained soils is provided on the attached
Figure A2. Pocket penetrometer readings were not collected in the test pits where coarse-grained material
was encountered.
A.1.2.2 Infiltration Tests
CGT performed six infiltration tests at the site within test pitsTP-1 through TP -6, at a depth of about 5 feet
bgs. Details regarding the test procedure and results of the tests are presented in Appendix B.
A.1.3 Material Classification & Sampling
Representative disturbed (grab) samples of the soils encountered were obtained at select intervals within the
test pits. A qualified member of CGT's geological staff collected the samples and logged the soils in general
accordance with the Visual -Manual Procedure (ASTM D2488). An explanation of this classification system is
attached as Figure A2. The grab samples were stored in sealable plastic bags and transported to our soils
laboratory for further examination and testing. Our geotechnical staff visually examined all samples in order
to refine the initial field classifications.
A.1.4 Subsurface Conditions
Subsurface conditions are summarized in Section 2.3 of the geotechnical report. Detailed logs of the
explorations are presented on the attached exploration logs, Figures A3 through A8.
A.2.0 LABORATORY TESTING
Laboratory testing was performed on samples collected in the field to refine our initial field classifications and
determine in-situ parameters. Laboratory testing included the following:
Carlson Geotechnical Page A2 of A3
Appendix A: Subsurface Im,estigation and Laboratory Testing
Anytime SeB Storage Springfield
Spnngfieid, Oregon
CGT Protect Number G2305919
June 21, 2023
• Ten moisture content determinations (ASTM D2216).
• Six percentage passing the U.S. Standard No. 200 Sieve tests (ASTM D1140).
• One Atterberg limits (plasticity) test (ASTM D4318).
Results of the laboratory tests are shown on the exploration logs.
Carlson Geotechnical Page A3 of A3
ANYTIME SELF STORAGE- SPRINGFIELD, OREGON
FIGURE Al
Exploration Key
Project Number G2305919
PL ---- L�
Atterberg limits (plasticity) test results (ASTM D4318): PL = Plastic Limit, LL = Liquid Limit, and MC= Moisture Content
MC
(ASTM D2216)
❑ HNES CONTENT(°.t}
Percentage passing the U.S. Standard No. 200 Sieve (ASTM Of 140)
SAMPLING
\j GRAB
Grab sample
'BULK
Bulk sample
Standard Penetration Test (SPT) consists of driving a 2 -inch, outside -diameter, split -spoon sampler into the undis-
SPT
turbed formation with repeated blows of a 140 -pound, hammer falling a vedical distance of 30 inches (ASTM D1586).
The number of blows (N -value) required to drive the sampler the last 12 inches of an 18 -inch sample interval is used to
characterize the soil consistency or relative density. The drill rig was equipped with an cat -head or automatic hammer to
conduct the SPTs. The observed N -values, hammer efficiency, and N60 are noted on the boring logs.
[7
Modified California sampling consists of 3 -inch, outside -diameter, split -spoon sampler (ASTM G3550) driven similarly to
N MC
the SPT sampling method described above. A sampler diameter correction factor of 0.44 is applied to calculate the equiv-
alent SPT N60 value per Lacroix and Ham, 1973.
LI CORE
Rock Coring interval
SH
Shelby Tube is a 3 -inch, inner -diameter, thinwalled, steel tube push sampler (ASTM D1587) used to collect relatively
undisturbed samples of fine-grained soils.
Wildcat Dynamic Cone Penetrometer (WDCP) test consists of driving 1.1 -inch diameter, steel rods with a 1.4 -inch
diameter, cone tip into the ground using a 35 -pound drop hammer with a 15 -inch free -fall height. The number of blows
WDCP
required to drive the steel rods is recorded for each 10 centimeters (3.94 inches) of penetration. The blow count for each
interval is then converted to the corresponding SPT N60 values.
Dynamic Cone Penetrometer (DCP) test consists of driving a 20 -millimeter diameter, hardened steel cone on 16-
DCP
millimeter diameter steel rods into the ground using a 10 -kilogram drop hammerwith a 460-millimeterfree-fall height. The
depth of penetration in millimeters is recorded for each drop ofthe hammer.
POCKET
Pocket Penetrometer test is a handheld instrument that provides an approximation of the unconfined compressive
PEN. (tsf)
strength in tons per square foot (tsf) of cohesive, fine-grained soils.
CONTACTS
Observed (measured) contact between soil or rock units.
---
Inferred (approximate) contact between soil or rock units.
— —
Transitional (gradational) contact between soil or rock units.
ADDITIONAL NOTATIONS
Itaim
Notes drilling action or digging effort
{ Braces }
Interpretation of material origintgeologic formation (e.g. { Base Rock} or { Columbia River Basalt})
All measurements are approximate.
6M 815
ANYTIME SELF STORAGE - SPRINGFIELD, OREGON
FIGURE A2
Soil Classification
Project Number G2305919
Classification of Terms and Content
Grain Sim
us ....
NAME: Group Name and Symbol
Fines <CMO (0.075 mm)
Relative Density or Consistency
Fine 4M0 -p pgQ5mm)
Color
Sand Modum M-MO(2mm)
Moisture Content
Coarse #10-A(4I5 mm)
Plasticity
A-
Fire p4 - 0.I5 inch
Gravel
Other Constituents
Other Grain Shape, Approximate Gradation
Coarse inch -3 inches
Cobbles Stu 12 inches
Organics, Cement, Structure, Oa«etc.
Geologic Name or Formation
Boulders > 12 inches
-Gained (Granular) Soils
Coarse
Relative Density
Minor Constituents
SPT
percent
N�Value Densiy
by Volume DescriptorExanpk
0-4 Very Loose
0-5% `Trace s pat of soil description Inc. sift"
4-10 Loose
10-M Medal Deme
5-15% With"as pad of group name VOORLY GRADED SAND WITH SILT"
W-50 Dmse
15-48% Meder to group name SILTYSAND"
>50 Very Dense
Fine -Grained (Cohesive) Soils
SPT Toaene tsf Pocket Pen tsf Consistency Manual Penetration Test
Nei
Minor Constituents
Shear Strength Unconfined
<2 <013 <0.25 May Son Thumb penetrates more than 1 inch
Percent
2-4 0.13-0.25 0.25-050 Son Thumb penetrates about 1 inch
by Volume Descriptor Example
0-5% irace"as pad of soil description Yrerefine-graireasand'
4-8 0.25-0.50 050-L00 Medium Stiff Thumb penetrates eboat Y. inch
8-15 (LED -1.00 L00-200 Stiff Thumb penetrates less ten/, in ch
5-15% Sonni pad of soil description-somefine-graireasan
15-M 1.00-2.00 200-400 Very Stiff Reaaiy indented by thumbnal
15-30% Wiffil insider group name SILTWITH SAND"
>30 >200 >400 Herd Dilficulto indent b thumbreil
30-49% Mociffierto group name %ANDYSLT'
Moisture Content
Structure
Dry: Absence of moisture, costs, dyto the touch
SiratNed Alternating layers of materiel « color >fi mm thick
Motet: Leaves moisture on hand
Lamiwted Alternating layers< 6 mm thick
Wet: Visible tee water, likely from below water table
Fissured: Breaks along cathode fracture planes
Plasticity DryStrength Dilatancy Toughness
Slickensiaea: Stdatea, polished, or glossy fracture planes
Blocky. Cohesroe soil that can be broken down into small angular lumps
ML
Non to Low Non to Low Slowto Rapid Low, can t roll
which resist further breakdown
CL
Lowto Medium Medium to High Noneto Slow Medium
MH
Medium to High Lowto Medium None to Slox Lox to Medium
Lenses: Has small pockets of different soils, note thickness
CH
Meaiumto High High to Very High None High
Homogeneous: Same color and appearance Nrougndut
Visual -Manual Classification
Major DNiaone Group Typical Nemes
Symbols
Clean
GW Well -graded gravels and gravel mixtures,INleormaFes
Coarse
Cxmets. 50%«moxa
Gravels
Go Poorly -graded gavels and graveysana mixtures, Mk orro Fes
Signed
mfersden
M pb 4sma.
Gravels
CHA By gavels, grevebNsandimatures
Soils:
with Fines
GC Ctayeygrevels, greveysendldsy matures
M«etha
50%retaneaclean
sw Well-grackodsoundsand gavelN senb,Mk«ne Fes
on No. 200
Sands: Morethen
Sends
SP PoodygaRE sends and gravelly sands, M.. Fes
5Ne
Sends
SM Say sails, sacWsiX matures
sieve
sievng
e
No.4 sieve
SC Clayey sands, sandiclay mixtures
with Fines
M. Inorganic silts, rock flour, clayey sib
ft. -Grained
Sift anti Clays
Sift
Inorganic clays of low N medium plank ,leen days
Soils:
Low Plasticity Fines
Q Organic soil of low plasticity
50 %or more
Passes N.
tat NOIgaaL sifts, clayey sib
200Sieve
Si and Ctays
High Plasticity Fires
C!1 Inorganic clays of high plasticity, fat clays
011 organic sat of medium to high plasticity
Higaty Organic Soils
PT Peal meB, acl ether highly organic soils
References'
LT�'L
ASTM D2487StandafdPractice for C�ssificationofSoils far Engineering Purposes (Unified Soil Classifica4onS)¢ten)
ASTMD2488 Standard Practice fbiesaiption andldenfiicafion of Soils (VisuaWanualProcedure)
maspr-nm
Teaagi K., and Peck, R.B., 184$ Soil Mechanics in Engineering Practice, John why& Sons.
FIGURE A3
ply
Carlson Geotechnical
A Umsion &Carlson Testing, Inc.
Test Pit TP -1
www cadsontesting.com
PAGE 1 OF 1
CLIENT Brandon
Bennet
PROJECT NAME
AnNime Se I Storage Springtdd
PROJECT NUMBER G2W5919
PROJECT LOCATON
High Banks Road - SpmgBaH Oregon
DATE STARTED
(IMM GRg1ND ELEVATION 4921t
ELEVATION DATUM See Figure 2
W THEIR
Sunnv
80°F SURFACE Graven Fl
WGGED EY AET
REVIENED BV BMW
E%CAVATION CONTRACTOR Doug Shepherd iDut er s
SEEPAGE —
EOItFMEW Bobcat M1 excavalcr
GROUNDWATER DURING DRILLING --
E%CAVATION METHOD 24 nch lotlhetl bucket
GROUNDWATER AFTER E%CAVATION —
w
w
r
AWOCPN.VALUEA
0^
Z�
3
t�m
a(Q�j
Sc
p
u
MATERIAL DESCRIPTION
Z
W
u
Wp
Y
j a
PL LL
�!
j
O.
5§
MCJ
hu
0
J
0
4
U
z
8
❑ FINES CONTENT (%) ❑
0
0 20 40 80 80100
Glp
POORLY GRADED GRAVEL WTH SILT FILL
GM
Baovm, dry to moist, angular to ronnded up to
FILL
2 -inches in diameter
ELASTIC SILT RLL: Brown With gray and orange
moll mcg, medium plasticity, trace rounded
4'0
gravel up to 2 -inches in diameter.
490
MH
2
3]5
RAE
100
FILL
1
2.0
3.0
ELASTIC SILT: Very diff, brown, most, high
plasticity, some fine-grained send.
2.5
488
4
2.]5
With fine-grained sand below 5 feet bgs.
• as
RA
100
2
488
MH
8
489
8
RA
100
3
as
482
10
• Test pit terminated at 10 feet bgs.
• R-1 ,as performed within the test pit at a depth
d 5 fed bgs. See Appendix B for test results. Test
480
pit extended beyond that depth following
completion dtesting.
• No groundwater or caring encountered.
• Test pit loosely backfilled with excavated material
upon completion.
478
FIGURE A4
ply
Carlson Geotechnical
A Uvision &Carlson Testing, Inc.
T2Si Pit TP -2
www cadsontesting.com
PAGE 1 OF 1
CLIENT Brandon
Bennet
PROJECT NAME
AnNime Se I Storage Springtcd
PROJECT NUMBER G2W5919
PROJECT LOCATION
High Banks Road - SpmgBeH Oregon
DATE STARTED
(IMM GROUND EI- VATB]N 4921t
ELEVATB]N DATUM See Figure 2
WEATHER
Sunnv
80°F SURFACE Graven FI
LOGGED EY AET
RMENED BV BMW
EKCAVAMN CONTRACTOR Doug Shepherd Oiriwxrks
SEEPAGE —
EQUI ME NT Bobcat M1 excavator
GROUNDWATER DURING DRILLING --
E%CAVATB]NMETHOD 24Nnch lotlhetl bu&d
GROUNDWATERAFTERE%CAVATIM —
w
w
r
AWOCPN.VALUEA
0^
Z�
3
t
�m
a(Q�j
Sc
p
u
MATERIAL DESCRIPTION
Z
W
u
Wp
Y
j a
PL LL
�!
j
O.
5§
1�
hu
J
0
J
0
4
U
8
z
U
8
)...
❑ FINES CONTENT (%) ❑
0
0 20 40 80 80100
POORLY GRADED GRAVEL W SILT FILL
GP-
Brown, must, subronnded to rounded up to
GM
2 -inches in diameter, or edium plashoy, sit foes.
FILL
1.0
ELASTIC SILT RLL: Dark brown with red! and
p&RA-E
100
black moling, must, medium plasticity, trace
490
MH
angular gravel up to 1 -inch in clam star
2
1
275
FILL
325
2.0
SARDY ELASTIC SILT: Stif to very diff brown,
moist, medium plasticity, with foe -grained send.
20
488
4
2.5
• O
100
2
2
ze
488
MH
8
RAE
100
3
n
484
8
482
10
• Test pit terminated a110 feet bgs.
• IT -2 w as performed within the test plat a depth
of 5 feet bgs. See Appendix B for test results. Test
480
pit extended beyond that depth following
completion oftesting,- No groundwater or coming
encountered,
• Test pit loosely backfilled with excavated material
upon completion.
478
FIGURE A5
ply
Carlson Geotechnical
A Uvision of Carlson Testing, Inc.
Test Pit TP-3
www cadsontesting.com
PAGE 1 OF 1
CLIENT Brandon
Bennet
PROJECT NAME
AnNime Se I Storage hringfeld
PROJECT NUMBER G2W5919
PROJECT LOCATION
High Banks Road - Sgmgfield Oregon
DATE STARTED
61923 GR131ND ELEVATION 4921t
ELEVATION DATUM See Figure 2
W THEIR Sunnv
8WF SURFACE Graven Fl
WGGED BY AET
RIMENED BV BMW
EKCAVATION CONTRACTOR Doug Sheghed Oiriwaks
SEEPAGE —
EQUIPMENT Bobca1341 excavator
GROUNDWATER DURING DRILLING --
EKCAVATIONMETNOD 24Nnch boched bu&d
GROUNDWATERAFTEREI(CAVATION —
w
w
r
AWOCPNa VALUEA
0^
Z�
3
t�m
a(Q�j
Sc
p
u
MATERIAL DESCRIPTION
Z
W
u
Wp
Y
j a
PL LL
�!
j
O.
5§
MCJ
hu
0
J
0
4
U
z
8
❑ FINES CONTENT (%) ❑
0
0 20 40 60 80100
GP
POORLY GRADED GRAVEL WTN SILT FILL
GM
Broom, mdsb, subron died to rounded up to
FILL
2-inches in diam eter, in edium plasticity sit foes.
ELASTIC SILT: Very stiffto had, brown, moist,
medium plasticity, trace black flecks, brace orange
4'S
mol trace fine-grained sand.
log,
490
2
4.5
225
4.0
3j��
pLORAE
100
4.5
488
4
4.5
Withfine-gained sand below5feetbgs
MAE
100
MH
2
a:
486
Traceweathered rockfmgments below Tfeetbgs,
6
finable under hand pressure.
4848
RAE
A
100
43
3
as
482
GP
POORLY GRADED GRAVEL WIN SANG
rlense, brown, moist, subronn led to
10
lMedium
ronnded, up to 34nches in diameter, with
foe-grained send, some medium plasticity sit
foes.
• Test pt terminated! x110 feel bile
480
• R-3 was pertormed within the test pt at a depth
of 5 feet bgs. See Appendix B for test results. Test
pit extended beyond that depth following
completion oftesting.
• No groundwater or caving encountered.
• Test pt loosely backfilled with excavated material
upon completion.
478
FIGURE A6
P•���y
Carlson Geotechnical
A Umsion of Carlson Testing, Inc.
Test Pit TPS
www cadsontesting.com
PAGE 1 OF 1
CLIENT Brantl.
Bennet
PROJECT NAME
MNime Se I Storage Springteld
PROJECT NUMBER G2W5919
PROJECT LOCATION
Hinh Banks Road - SprinoaeH Oreo.
DATE STARTED
6MM GRg1ND ELEVATION 4921t
ELEVATION DATUM See Haure 2
W THEIR Sunnv
8WF SURFACE Sol
LOGGED BY AET
RIMENEDBY BMW
EKCAVATION CONTRACTOR D.o Shepherd Oftt a .
SEEPAGE —
EQUI ME NT Bobcat 341 excavalcr
GROUNDWATER DURING DRILLING --
EKCAVATIONMETHOD 24Nnch lotlhetl bucket
GROUNOWATERAFTERE%CAVATION —
w
w
r
AWOCPNa VALUEA
0^
Z�
3
t�m
a(Q�j
Sc
p
u
MATERIAL DESCRIPTION
Z
W
u
Wp
Y
j a
PL LL
�!
j
O.
5§
MCJ
w
0
J
0
4
p
8
z
p
8
)V
❑ FINES CONTENT (%) ❑
(9
0
0 20 40 60 80100
OL
ORGANC SOIL Brown, dry, low plalicily,
abundanlroollels.
0.]5
ELASTIC SILT WTH SAND: Veryband,,
moist, high plasticity, with fine-grained sand, some
2.5
submuntletl to rounded gavel up to 1 -inch in
diameter
3.0
- - - -
4911
MH
2
3.0
R1A
100
3.5
_
1
4.0
488
4
4.0
POORLY GRADED GRAVEL W TH COBBLES
° ',°
PND SAND: Medium dense to dense, brain,
D
moist, submuntletl to rounded, up to 4in±es in
O
diameter, doth fine -to coarse-grained sand, some
m ediu in plasticity silt fines.
t
RA
D
Tracesil andsomecaving below5feetbgs.
2
100
J
o
O
486
° Q°
6
D
O
GP
3A
100
484
OD
8
O
I I
O
I I
482
°
10
• Tesl pit terminated at 10 feet bgs.
• R-4. ped.med within the test plat a depth
of 5 feet bgs. See Appendix B for test results. Test
480
pit extended beyond that depth following
completion oftesting.
• Caving encountered below 6 feet bgs.
• No groundwater encountered,
• Test pit loosely backfilled wlh excavated material
upon completion.
478
FIGURE A7
P•���y
Carlson Geotechnical
A OMsion of Carlson Testing, Inc.
T2Si Pit TP -5
www cadsontesting.com
PAGE 1 OF 1
CLIENT Brandon
Bennet
PROJECT NAME
Anytime Se I Storage Springfield
PROJECT NUMBER G2W5919
PROJECT LOCATION
High Banks Road - SpmgfieH Oregon
DATE STARTED
6MM GRCIU D ELEVATION 494t
ELEVATION DATUM See Figure 2
WEATHER Sunny
80°F SURFACE Sol
LOGGEDEY AET
REVIENEDBY BMW
MCAVATION CONTRACTOR Dong Shepherd Oftt k.
SEEPAGE -
EpUFM3NT Bobca1841 excavalar
GROUNDWATER DURING MILLING --
MCAVATIONMETHOD 24Nnch lotlhetl bucket
GROUNOWATERAFTERE%CAVATION -
w
w
r
AWOCPN.VALUEA
0^
Z�
3
t�m
a(Q�j
Sc
p
u
MATERIAL DESCRIPTION
Z
W
u
Wp
Y
j a
PL LL
�!
J
j
O.
5§
MCJ
w
0
0
4
p
8
z
p
8
)V
❑ FINES CONTENT (%) ❑
0
0 20 40 60 80100
—
OL
OC SOIL: Brown, dry, low plalicily,
abundenlroollels.
ELASTIC SILT GRAVEL: Medium stf,,
brown, mcis1, high plasticity, wtih su bmunded to
rounded gavel up to 2 -inches in diameter,
MH
492
POORLY GRADED GRAVEL: Medium claws, —
2
broom, moist, subrounded to rounded up to
D
&inches in diameter, some medium plasticity sit
490
O
fines, somefne-to coarse-grained sand.
4
D
RA
100
O
With coarse-grained sand, trace silt fines
I
4%f
below 4'/z feet bgs.
1
a '.
100
oOD2AE
i
A
°
488
6
O
GP
OD
D
486
O C
8
100
oO
9A
°
484
10
• Test pit terminated at 10feet bgs.
• IT -5 was performed within the test pit at a depth
d 5 feet bgs. See Appendix B for test results. Test
482
pit extended beyond that depth following
completion dtesting.
• No caong or groundwater encountered.
• Test pit loosely backfilled with excavated material
upon completion.
480
FIGURE A8
P•���y
Carlson Geotechnical
A OMsion of Carlson Testing, Inc.
Test Pit TP -6
www cadsontesting.com
PAGE 1 OF 1
CLIENT Brandon
Bennet
PROJECT NAME
AnNime Se I Storage Springterd
PROJECT NUMBER G2W5919
PROJECT LOCATION Hinh Banks Road - SprinpflelE Oreeon
DATE STARTED
61923 GRg1ND 110-11111 491 It
110-1111i DATUM See Haure 2
V T11ER Sunnv
8WF SURFACE Sol
LOGGEDEY AET RIMENEDBY BMW
EI(CAVATNN CONTRACTOR Dcuu Shepherd OHwaks
SEEPAGE -
EQUIPMENT Bobcat 391 excavalor
Q GROUNDWATER DURNG MILWG 10.O fi / E. 481.0 fi
EI(CAVATNN ME fill 24 nch lotlhetl bucket
GROUNDWATER AFTER EXCAVATION -
w
w
r
AWOCPN.VALUEA
0^
Z�
3
t�m
a(Q�j
Sc
p
u
MATERIAL DESCRIPTION
Z
W
u
Wp
Y
j a
PL LL
�!
j
O.
5§
MCJ
w
0
J
0
4
p
8
z
p
8
)V
❑ FINES CONTENT (%) ❑
0
0 20 40 60 80100
—
OL
ORGANIC SOIL: Brown, tlry,low plaicity,
dentrootlets.
POORLY GRADED GRAVEL V SANG
490
OD
Medium tlerae, brown, or oisl, subround etl to
rwntletl up to 3 m±es in diam star, with fine -lo
medium grainetl sand, son e in edium p laslbily all
foes.
OD
2
OD
488
100
ODpLORAE
OD
Trace sift below 4 feet bgs,
486
D
O
GP
RA
2
100
OD
6
RAE
100
I ncreased in oislure and fn e -to coarse -gain etl
D
sand below 6 feet bgs.
fj
3
s
o
O
489
8
482
OD
100
DRA
a
O
10
4
• Teel pit lerminaletl al 10 feel bgs.
• IT -6 vas performetl All the lest pit at a depth
480
of5feet bgs. See Appendix B for test results. Test
pit extended beyond that depth following
completion oftesting.
• Groundwater observed at 10 feel bgs.
• No caving encountered,
• Test pit loosely backfilled with excavated material
upon completion.
478
Carlson Geotechnical
Bend Office
(541)330-9155Gp
RL`S0
Eugene Office
(541)345-0289
A Division of Carlson Testing, Inc.
Salem Office
(503) 589-1252
If
Phone: (503) 601-8250
Tigard Office
(503)684-3460
w .cadsontesting.com
Appendix B: Results of Infiltration Testing
Anytime Self Storage Springfield
High Banks Road
Springfield, Oregon
CGT Project Number G2305919
June 21, 2023
Prepared For.
Brandon Bennett
Signal Ventures
2538 NE Division Street
Bend, Oregon 97703
Prepared by
Carlson Geotechnical
Office: 18270 SW Scones Ferry Road, Suite 6, Durham, Oregon 97224
Mailing: P.O. Box 230997, Tigard, Oregon 97281
Appendix B: intimation Testing
Anytime SeB Storage Springfield
Springfield, Oregon
CGT Pr*ct Number G2305919
June 21, 2023
B.1.0 INTRODUCTION
The project civil engineer Mr. Jack Mitchell, P.E., of Ashley & Vance Engineering, requested infiltration
testing at six locations at depths of about 5 feet bgs on a site map provided to CGT. The location of the
infiltration tests are shown on the Site Plan attached to the main report as Figure 2.
B.2.0 TEST PROCEDURE
Six infiltration tests (IT -1 through IT -6) were performed in general accordance with the 1980 EPA falling head
percolation test procedure (as allowed in Section 4.16.3 of the City of Springfield's 2012 stormwater manual).
The tests were performed within the prepared test pits (TP -1 through TP -6), which were advanced to the
infiltration test depth (5 feet bgs) using a Bobcat 341 mini -excavator with a 18 -inch -wide toothed bucket.
Once the test pits were advanced to the infiltration test depth in TP -1 through TP -3, a 6 -inch diameter PVC
pipe was pushed about 6 inches into the soil at the test depth to obtain a proper seal between the PVC pipe
and surrounding soils. An approximate 2 -inch layer of clean gravel was placed within the test pipe to prevent
scouring the soil with water during testing. In TP -4 through TP -6 the presence of coarse-grained gravelly
soils (GP -GM) inhibited pushing the PVC pipe into the subsurface material. As an alternative, each PVC pipe
was seated in small prepared holes and granular bentonite was used around its base to create a proper seal.
In TP -1 through TP -3, the test pipes were filled with about 12 inches of water, and the soils were allowed to
soak for 4 hours in accordance with the test method. After the soaking period, the water level within the test
pipes was adjusted to 6 inches above the gravel and the drop in water level was recorded at 30 -minute
intervals over 3 to 4 trials. Measurements were taken with a tape measure from a fixed point (top of pipe)
and recorded to the nearest one -sixteenth of an inch.
We attempted to soak the subsurface soils in TP -4 through TP -6 by pouring an approximate 12 -inch column
of water into the pipe. The water infiltrated into the subsurface materials in less than 10 minutes. This was
repeated a second time with similar results; therefore, we immediately proceeded with the infiltration test in
general accordance with the test method. We poured about 6 inches of water into the pipe and recorded the
time required for the water to completely infiltrate into the subsurface materials during each trial. We
administered three to four trials in each infiltration test.
B.3.0 INFILTRATION TEST RESULTS
The following tables present the raw data that we observed from the infiltration tests.
Carlson Geotechnical Page B2 of B5
Appendix B: Infiltration Testing
Anytime Seff Storage Springfield
Springfield, Oregon
CGT Protect Number G2305919
June 21, 2023
Table 131 Results of Infiltration Test IT -1
tttmm
jAmilii Sd Staa¢-Spdrgleld
Dde
61912D23
Exllsalm NunMr.
TP 1
Ted Mal
Ercased FdliMHeM
I.Diarela ipe:
6mineis
Irfilhdim Ted D:
5 bd
S dl a Falreim ted deph
MH
see a plormm log for deal
Presebwam Stat Tim is
7:30 AM
Presawam Notes:
Waw alrledtopipe Wiximally very Msbmanhin Rini
P resauram Erd ime
11 54A
Herd Duirg Presauafart
-12 inches
TimeRemains
imelinerval
Measwement
Dray in Wile level
I41twan Res—
1:81 PM
(Mirxfes)
(iricMs)'
(ochres)
(inchres per haul
11:54PM
--
37 5l8
—
Weler aQuted b povide 6 ish head
WabawI.1edbpovide6irch Mal
1224AM
30
41 18
3 12
7
— 4038
1225PM
—
38
265 PM
30 42 12
Wand alusbd b provide 6 irch Mal
1255PM
30
41
3
6
1255PM
--
3818
2
4
Webxalusldbpovide6iehteal
1:25 PM
30
41
2 718
5 314
' Measured b newest 1116 inch
"Values cdculeed as raw (ufactaed) rates.
Table B2 Results of Infiltration Test IT -2
Lmmm
ArryEme Seff Sbrage-Spingleld
Dao
6'N2D23 Ex plareim NurnMc TP2
TestMal
Ercased FdliMHeed
I.Dianda dPips
6bcMs Iraltrdm Test Deptic Steel
S dl a Falreim ted deph MH
see a datum bg for deal
Preselwa7m Stat Tim is 82D AM
Presalraim Nobs:
Wee alded b pipe agrme imakely mey hos b marlin lNrch Mal
PI
H eel Dsirg P resauafoe-12irches
TimeR
imelaeri Measuemet
Dmpin Waelevd
Irilhmm Ras"
ma s
(Misles) (ircMs)'
(bcMs)
Qrc Fes per Ms)
1231 PM
-- 40318
—
Weler aQutedb provide 6 inch Ford
1:81 PM
30 43 78
3 12
7
1:83 PM
— 4012
—
Weler aQuted b povide 6 ish head
1:33PM
30 43 18
2 SB
5 114
1.35PM
— 4038
—
Weer aQusbd b provide 6 ish head
265 PM
30 42 12
2 1B
4 114
286 PM
— 1 40 SB
1 —
Webr aQusbd b provide 6 ieh head
236 PM
30 42 SB
2
4
"Mase el b newest 1116 irch
•• Vdlcs adcdebd se rsv(ufw" relies.
Carlson Geotechnical Page B3 of B5
Appendix B: Infiltration Testing
Anytime SeB Storage Springfield
Springfield, Oregon
CGT Pro/ect Number G2305919
Jura, 21, 2023
Table B3 Results of Infiltration Test IT -3
tttabort
Anytime SeffStaage-Spcngleld
iDar
ww2023
Exdormm N urnbec TP3
TestMdhod
Encased Faling HeM
Inner Diameter d Pipe:
6ictes
i9lhmm Test Depr 5fea
S dl a n6lmm betcla r
IMH
see. plormm log br email
P resibormm Stat ima
840 AM
Presalrmm Nobs:
Waa arced to pipe apirmimaely every hour to machin 12 -inch Mad
P resibormm End ime:
1245 PM
Head During Presahffion,
-12 inches
fine
imeldavaI
Measurement
Dmp in Waaleia
IrSal Ren^
Remaks
(Messe)
(ictesp
(aches)
(1 -has pa Fdr)
1246PM
--
59
—
Waler a4usted to provide 6 inch head
1:16PM
30
59 114
114
112
1:17PM
—
58 58
—
Wal,.4usrd b povide 6 inch head
1:47 PM
30
58 78
114
112
1:47 AM
—
5378
—
Waba*slldbpovide6ichhead
217 AM
30
5918
114
112
" Meauree b neaat 1116 itch
"Values cacubbe as rav (urfabred) rasa
Table B4 Results of Infiltration Test IT -4
Trial Number Time Interval Initial Head' Final Head' Drop in Water Level Raw Infiltration Rate2
(seconds) (inches) (inches) (inches) (inches(hour)
1 1 6 0 6 21,600
10,800
3 2 6 0 6 10,800
' Measured to nearest l/lrimh using a measuring tape and top of pipe as a fixed datum.
0 Calculated infiltration rates do not include any safety or correction factors and are rounded to the nearest 1incNhour.
'Subsurface material consisted ofrelatWly clean poorly graded gravel (G P) see test pit lug for additional information.
Carlson Geotechnical Page B4 of B5
Appendix B: Infiltration Testing
Anytime SeB Storage Springfield
Springfield, Oregon
CGT Pr*ct Number G2305919
June 21, 2023
Table B5 Results of Infiltration Test IT -5
Table B6 Results of Infiltration Test IT -6
Trial Number Time Interval Initial Head' Final Head' Drop in Water Level Raw Infiltration Rater
(seconds) (inches) (inches) (inches) (inchesthour)
1 47 6 0 6 459
2 52 6 0 6 415
3 54 6 0 6 400
' Measured to nearest 1/16 -inch using a measuring tape and top of pipe as a fired datum.
r Calculated infiltration rates da not include any safety or correction factors and are rounded to the nearest l irmwhour.
'Subsurface material consisted of relathrely clean poorly graded graeel (GP) see test pi log for additional information.
B.4.0 DISCUSSION
As detailed above, observed infiltration rates varied significantly across the site and is attributable to the
presence of varying subsurface materials at the test depths. Raw (unfactored) infiltration rates in the silty
soils (MH) in TP -1 through TP -3 varied from a/: to 5a/. inches per hour. Raw (unfactored) infiltration rates in
the poorly graded gravel (GP) in TP -4 through TP -6 varied from 65 to 10,800 inches per hour.
With regard to the test locations at TP -4 and TP -6, we recommend the raw infiltration rate be assigned as
100 inches per hour as means to add some conservatism in the design. In the event a larger infiltration rate
is desired, we recommend an increased scale of testing be performed using a larger volume of water
delivered from a steady water source (e.g. water truck, fire hydrant, etc.).
Please note the above infiltration rates do not include any safety or correction factors. We recommend the
stonnwater infiltration system designer consult the appropriate design manual in order to assign appropriate
safety/correction factors to calculate the design infiltration rate for the proposed infiltration systems Once
the design is completed, we recommend the infiltration system design (provided by others) and location be
reviewed by the geotechnical engineer. If the location and/or depth of the systems) change from what was
indicated at the time of our fieldwork, additional testing maybe recommended.
Carlson Geotechnical Page B5 of B5
lacdm'. AMSme SerSrorade-Sinndleid
pat
BIw2023 Explordon Number TP3
Test Mdbd Ercased F9ing Heal
Imo Dimderdpw
Birches I rdltatlon Ted Deem 15fed
Sol eiMtrafonsrdepk IGP
see espbmlonlcgforde0i
Presa52ton Sta Tme 212PM
Presmraoon Nolan;
12-imMsdw4 added Wbemdb ues i[dmnedmWinunderl0
mines. InmasenMescme ImNseaingdpiNisbdiwedbhwe
dteed NelTstdan
PrembrafonEMTme 226PM
Heal Dumg Pnsabmfon WA
Time
Tmelrrenal Measurme6
Drop in Wale lead
Ir6trSm Rat'
Reade
(Mines) (inchesy
(inches)
(inahmpehord
230 PM
— 6
—
Water adpsted to provide 6 inch red
r
2'.S PM
5% 0
6
63 Ll
2N PM
— 6
West adiiii to provide 6 inch red
r
IV PM
&U 0
6
0114
243 PM
— 6
West adysad to provide 6 inch red
r
246 PM
SS 0
6
66 ]IB
Memurel to nearest 1116 inch
"Vdues aalculdel are res (urrtecbred) rates.
Table B6 Results of Infiltration Test IT -6
Trial Number Time Interval Initial Head' Final Head' Drop in Water Level Raw Infiltration Rater
(seconds) (inches) (inches) (inches) (inchesthour)
1 47 6 0 6 459
2 52 6 0 6 415
3 54 6 0 6 400
' Measured to nearest 1/16 -inch using a measuring tape and top of pipe as a fired datum.
r Calculated infiltration rates da not include any safety or correction factors and are rounded to the nearest l irmwhour.
'Subsurface material consisted of relathrely clean poorly graded graeel (GP) see test pi log for additional information.
B.4.0 DISCUSSION
As detailed above, observed infiltration rates varied significantly across the site and is attributable to the
presence of varying subsurface materials at the test depths. Raw (unfactored) infiltration rates in the silty
soils (MH) in TP -1 through TP -3 varied from a/: to 5a/. inches per hour. Raw (unfactored) infiltration rates in
the poorly graded gravel (GP) in TP -4 through TP -6 varied from 65 to 10,800 inches per hour.
With regard to the test locations at TP -4 and TP -6, we recommend the raw infiltration rate be assigned as
100 inches per hour as means to add some conservatism in the design. In the event a larger infiltration rate
is desired, we recommend an increased scale of testing be performed using a larger volume of water
delivered from a steady water source (e.g. water truck, fire hydrant, etc.).
Please note the above infiltration rates do not include any safety or correction factors. We recommend the
stonnwater infiltration system designer consult the appropriate design manual in order to assign appropriate
safety/correction factors to calculate the design infiltration rate for the proposed infiltration systems Once
the design is completed, we recommend the infiltration system design (provided by others) and location be
reviewed by the geotechnical engineer. If the location and/or depth of the systems) change from what was
indicated at the time of our fieldwork, additional testing maybe recommended.
Carlson Geotechnical Page B5 of B5