HomeMy WebLinkAboutRS_Geotechnical_Report_Testing_Lab_220218_v1Geotechnical Engineering Services
Fuel Cell Test Laboratory – DaVinci Laboratory
Renton, Washington
for
Blue Origin, LLC
February 18, 2022
Geotechnical Engineering Services
Fuel Cell Test Laboratory – DaVinci Laboratory
Renton, Washington
for
Blue Origin, LLC
February 18, 2022
17425 NE Union Hill Road Suite 250
Redmond, Washington 98052
425.861.6000
February 18, 2022 | Page i File No. 16933-001-33
Table of Contents
1.0 INTRODUCTION ................................................................................................................................. 1
2.0 PROJECT DESCRIPTION .................................................................................................................... 1
3.0 FIELD EXPLORATIONS AND LABORATORY TESTING ...................................................................... 1
3.1. Field Explorations .......................................................................................................................... 1
3.2. Laboratory Testing ........................................................................................................................ 1
4.0 PREVIOUS STUDIES .......................................................................................................................... 2
5.0 SITE CONDITIONS .............................................................................................................................. 2
5.1. Geology .......................................................................................................................................... 2
5.2. Surface Conditions........................................................................................................................ 2
5.3. Subsurface Conditions ................................................................................................................. 2
5.4. Groundwater Conditions ............................................................................................................... 3
6.0 CONCLUSIONS AND RECOMMENDATIONS ..................................................................................... 3
6.1. Earthquake Engineering ............................................................................................................... 3
6.1.1. Regional Seismicity ........................................................................................................... 4
6.1.2. 2018 IBC Seismic Design Information ............................................................................. 4
6.1.3. Liquefaction ....................................................................................................................... 5
6.1.4. Lateral Spread and Earthquake Induced Landsliding ..................................................... 6
6.2. Foundations Recommendations .................................................................................................. 6
6.3. Lateral Resistance ........................................................................................................................ 7
6.4. Earthwork ...................................................................................................................................... 7
6.4.1. Excavation Considerations ................................................................................................ 7
6.4.2. Subgrade Preparation ....................................................................................................... 7
6.4.3. Temporary Soil Cut Slopes ................................................................................................ 7
6.4.4. Structural Fill...................................................................................................................... 8
6.4.1. On-site Soils ....................................................................................................................... 9
6.4.2. Utility Considerations ........................................................................................................ 9
7.0 LIMITATIONS ..................................................................................................................................... 9
8.0 REFERENCES ................................................................................................................................. 10
February 18, 2022 | Page ii File No. 16933-001-28
LIST OF FIGURES
Figure 1. Vicinity Map
Figure 2. Site Plan
APPENDICES
Appendix A. Field Explorations
Figure A-1 – Key to Exploration Logs
Figure A-2 – Log of Boring
Appendix B. Laboratory Testing
Figures B-1 and B-2 – Sieve Analysis Results
Appendix C. Previous Explorations
Appendix D. Report Limitations and Guidelines for Use
February 18, 2022 | Page 1
File No. 16933-001-33
1.0 INTRODUCTION
This report presents the results of our geotechnical engineering services related to the Fuel Cell Test
Laboratory – DaVinci Laboratory for Blue Origin, LLC located at 1415 Maple Avenue SW in Renton,
Washington. The project site is shown relative to surrounding physical features on the Vicinity Map
(Figure 1) and the Site Plan (Figure 2).
Our services were completed in accordance with our proposal dated December 14, 2021. Our specific
scope for the geotechnical engineering services included:
■Reviewing previous explorations completed at and in the vicinity of the site as well as reviewing the
history of the site development;
■Completing one boring to characterize the subsurface conditions at the site;
■Completing geotechnical laboratory tests on samples collected from the boring;
■Performing analyses for seismic design and foundation support for the testing laboratory;
■Providing estimated static and seismic settlements; and
■Preparing this geotechnical design report.
2.0 PROJECT DESCRIPTION
We understand that a new testing lab will be constructed on the north side of the site using a
premanufactured “Dropbox” measuring roughly 37 feet in the east-west direction and 8 feet in the
north-south direction. A tower assembly will be constructed on the east side of the facility, extending about
20 feet above ground. We understand that the new structure will be relatively lightly loaded. The structure
is planned to be supported on a structural slab and the tower will be supported by a shallow base footing.
Hardscape improvements will be completed around the footprint of the premanufactured structure.
Historic loading on the site included topsoil stockpiles prior to construction of the existing warehouse on
the property in 1992, although the extent of the stockpiles is unknown.
3.0 FIELD EXPLORATIONS AND LABORATORY TESTING
3.1. Field Explorations
Subsurface conditions at the proposed laboratory location were evaluated by reviewing previous
explorations at the site completed by GeoEngineers in 2000, and by completing one boring (B-1) to a depth
of 51.5 feet beneath the footprint of the proposed laboratory. The approximate location of the explorations
are shown in Figure 2. A detailed description of the field exploration program and logs of the borings are
provided in Appendix A.
3.2. Laboratory Testing
Samples obtained from the boring were transported to our laboratory for additional classification and to
evaluate engineering properties. Representative samples were selected for moisture content testing,
February 18, 2022 | Page 2 File No. 16933-001-33
percent fines (material passing the U.S. No. 200 sieve) evaluation, and sieve analysis. Details of the
laboratory testing procedures are presented in Appendix B, Laboratory Testing.
4.0 PREVIOUS STUDIES
Our previous experience at the site includes geotechnical studies for others at the subject property. The
most recent study is summarized in our report titled “Report, Geotechnical Engineering Services, Renton
Switching Facility, Renton, Washington,” dated January 27, 2000. Test pits and borings were completed on
the property as part of these previous studies. These exploration locations are shown in Figure 2 and are
included in Appendix C.
5.0 SITE CONDITIONS
5.1. Geology
The project site is located at the northern end of the Green River Valley approximately 1/3 mile west of the
valley wall, about one mile east of the river and over two miles south of the south end of Lake Washington.
Published geologic information for the project vicinity includes a map titled “Geologic Map of King County”
(Booth, Troost & Wisher 2007). Subsurface soils are mapped as recent alluvium, which consists of
interlayered fine-grained sand and silt with occasional layers of organic silt and peat. The alluvial deposits
are as much as 150 to 300 feet thick in the central portion of the valley with less thickness near the valley
walls. The alluvium has moderate to high liquefaction potential, and often contain moderate to highly
compressible layers within the near-surface layers.
5.2. Surface Conditions
The site is currently occupied by a high-bay warehouse structure with parking and drive aisles on the north
and east. The proposed testing lab will be situated in the north portion of the existing parking area as shown
in Figure 2. Site grades are relatively level, varying from approximately Elevation 20 to 22 feet.
5.3. Subsurface Conditions
Based on our review of the previous explorations and the boring completed as a part of this study,
subsurface soils at the proposed testing laboratory and tower location consist of surficial fill overlying
alluvial deposits. Medium dense to dense sand and gravel was encountered below the alluvium at a depth
of about 23 feet in the current boring. Specific subsurface conditions encountered in boring B-1 are
described below.
We encountered 4 inches of surficial asphalt concrete overlying medium dense to dense silty sand with
gravel fill to a depth of approximately 7 feet in boring B-1. Beneath the fill the underlying alluvium consists
of an upper layer of medium dense grading to loose sand to a depth of approximately 18 feet. A 5-foot-thick
layer of medium stiff sandy silt was encountered between a depth of about 18 to 23 feet where the soils
transitioned to medium dense sand and gravel to the depth explored (51.5 feet).
February 18, 2022 | Page 3 File No. 16933-001-33
5.4. Groundwater Conditions
The groundwater level was observed at approximately 5.5 feet below the ground surface (bgs) at the time
of drilling. Groundwater conditions should be expected to fluctuate as a function of season, precipitation,
and other factors.
6.0 CONCLUSIONS AND RECOMMENDATIONS
The boring completed within the proposed testing laboratory area encountered deposits of loose sand with
a layer of compressible silt at depth. Based on the presence of the surficial medium dense to dense fill
overlying the alluvium and the anticipated lightly loaded testing facility (less than about 200 pounds per
square foot [psf] areal loading), we estimate post-construction static settlements of less than 1 inch.
Structures supported at grade at this site are at risk of settlement if a large earthquake resulted in
liquefaction of the underlying saturated sandy soils. The owner should understand that the type of
foundation systems planned for the laboratory and tower are susceptible to damage if liquefaction induced
settlement occurs. Structures should be evaluated and designed for life safety and prevention of collapse
by the structural engineer for the design earthquake.
A summary of primary geotechnical considerations for the proposed laboratory structure and tower is
provided below. The summary is presented for introductory purposes only and should be used in
conjunction with the complete recommendations presented in this report.
■ The site soils are susceptible to seismically induced liquefaction. We estimate that liquefaction
settlement could be in the range of 6 to 9 inches during the design earthquake based on the boring
completed within the footprint of the planned laboratory.
■ We understand the “Dropbox” laboratory will be founded on a slab, and the tower will be founded on a
4-foot-thick block foundation. Assuming an area floor load of less than 200 psf for the laboratory, and
an allowable soil bearing load of 2,500 psf for the block footing, we estimate that the foundations could
experience ½ to 1 inch of static post-construction settlement. These estimates assume subgrade
improvements will be completed as described below.
■ We recommend that the new slab and tower foundation be founded on a minimum of 18 and 24 inches
of structural fill, respectively. Based on the subsurface conditions encountered in the boring, the
existing fill may be suitable and should be evaluated during excavation. All structural fill should be
compacted to at least 95 percent of the maximum dry density (MDD) per ASTM D 1557.
■ Passive resistance should be evaluated using an equivalent fluid density of 300 pounds per cubic
foot (pcf) where footings are surrounded by structural fill compacted to at least 95 percent of MDD.
This value should be reduced to 225 pcf where footings are constructed against existing fill soils.
■ The on-site silty sand fill is moisture sensitive and will only be suitable for reuse as structural fill during
periods of dry weather.
6.1. Earthquake Engineering
GeoEngineers evaluated the site for seismic hazards including liquefaction, lateral spreading, fault rupture
and earthquake induced landsliding. Our evaluation indicates that the site has a low risk of lateral
February 18, 2022 | Page 4 File No. 16933-001-33
spreading, fault rupture and earthquake induced landsliding. However, our analyses indicate that the site
has a moderate to high risk of liquefaction during a design level earthquake as recommended in the 2018
International Building Code (IBC) and American Society of Civil Engineers (ASCE) 7-16. The liquefaction
hazard and building code site coefficients are presented below.
6.1.1. Regional Seismicity
The Puget Sound region is located at the convergent continental boundary known as the Cascadia
Subduction Zone (CSZ), which extends from mid-Vancouver Island to Northern California. The CSZ is the
zone where the westward advancing North American Plate is overriding the subducting Juan de Fuca Plate.
The interaction of these two plates results in three potential seismic source zones: (1) a shallow crustal
source zone, (2) the Benioff source zone, and (3) the CSZ interplate source zone.
The shallow crustal source zone is used to characterize shallow crustal earthquake activity within the North
American Plate at depths ranging from 3 to 19 miles bgs. The Seattle Fault Zone is considered a shallow
crustal source zone. The most recent major earthquake on the Seattle Fault Zone is estimated to have
occurred about 1,100 years ago. The site is located far from the Seattle Fault Zone.
The Benioff source zone is used to characterize intraplate, intraslab or deep subcrustal earthquakes.
Benioff source zone earthquakes occur within the subducting Juan de Fuca Plate at depths between 20
and 40 miles. In recent years, three large Benioff source zone earthquakes occurred that resulted in some
liquefaction in loose alluvial deposits and significant damage to some structures. The first earthquake,
which was centered in the Olympia area, occurred in 1949 and had a Richter magnitude of 7.1. The second
earthquake, which was centered between Seattle and Tacoma, occurred in 1965 and had a Richter
magnitude of 6.5. The third earthquake, which was located in the Nisqually valley north of Olympia, occurred
in 2001 and had a Richter magnitude of 6.8.
The CSZ interplate source zone is used to characterize rupture of the convergent boundary between the
subducting Juan de Fuca Plate and the overriding North American Plate. The depth of CSZ earthquakes is
greater than 40 miles. No earthquakes on the CSZ have been instrumentally recorded; however, through
the geologic record and historical records of tsunamis in Japan, it is believed that the most recent CSZ
event occurred in 1700.
6.1.2. 2018 IBC Seismic Design Information
The 2018 IBC references the 2016 version of Minimum Design Loads for Buildings and Other Structures
(ASCE 7-16) for the Site Class determination and the development of seismic design parameters. The loose
to medium dense granular soils below the water have moderate to high liquefaction potential, thus the site
falls under Site Class F per ASCE 7-16 Section 20.3.1. Site response analysis is required for Site Class F
sites per Section 11.4.8; however, Section 20.3.1 provided an exception for structures that have a
fundamental period of vibration equal to or less than 0.5 seconds, whereby the site class may be
determined in accordance with Section 20.3 and the corresponding site coefficients determined based on
mapped seismic parameters in Section 11.4.4. The values presented below assume that the proposed
structure will have a fundamental period of vibration equal to or less than 0.5 seconds.
Based on the subsurface data from the borings completed in the northwest corner of the site (including the
recently completed boring within the footprint of the laboratory) and the boring completed in the southeast
corner of the site, the site is best classified as Site Class D and Site Class E, respectively. Per ASCE 7-16
February 18, 2022 | Page 5 File No. 16933-001-33
Section 11.4.8, a ground motion hazard analysis or site-specific response analysis is required to determine
design ground motions for structures on Site Class D sites with S1 greater than or equal to 0.2g (where g
represents gravitational acceleration); and for structures on Site Class E sites with SS greater than or equal
to 1.0g and S1 greater than or equal to 0.2g. The mapped SS and S1 values for this site are 1.441g and
0.491g, respectively; therefore, these provisions apply.
Alternatively, the parameters listed in Table 1 below may be used to determine the design ground motions
provided Exception 2 and Exceptions 1 and 3 of Section 11.4.8 is used for Site Class D and Site Class E,
respectively. Using Exception 2 for Site Class D, the seismic response coefficient (Cs) is determined by
Equation (Eq.) (12.8-2) for values of T≤1.15TS, and taken as equal to 1.5 times the value computed in
accordance with either Eq. (12.8-3) for TL≥T>1.5Ts or Eq. (12.8-4) for T>TL, where T represents the
fundamental period of the structure and TS=0.62 seconds. Using Exceptions 1 and 3 for Site Class E, Fa is
taken as the value for Site Class C (equal to 1.2), and T is less than or equal to TS and the equivalent static
force procedure is used for design. T represents the fundamental period of the structure and the
fundamental period of the structure and TS=0.63 seconds.
We recommend the use of the following 2018 IBC parameters for short period spectral response
acceleration (SS), 1-second period spectral response acceleration (S1) and seismic coefficients (FA and FV)
for the project site.
TABLE 1. 2018 IBC DESIGN PARAMETERS
2018 IBC Parameter1 Value
Soil Profile Type D E
Short Period Spectral Response Acceleration, SS (g) 1.441 1.441
1-Second Period Spectral Response Acceleration, S1 (g) 0.491 0.491
Seismic Coefficient, FA 1.00 1.203
Seismic Coefficient, FV 1.812 2.224
Peak Ground Acceleration (g) 0.613 0.613
Site Amplification Factor for PGA, Fpga 1.1 1.1
TS (sec) 0.62 0.63
Notes:
1. Parameters developed based on latitude 47.467249 and longitude -122.222469 using the Applied Technology Council (ATC)
Hazards online tool (https://hazards.atcouncil.org/).
2. This value is only valid if the structural engineer utilizes Exception 2 of Section 11.4.8 (ASCE 7-16).
3. Per ASCE 7-16 Section 11.4.8 Exception 1.
4. For calculating TS only.
6.1.3. Liquefaction
Liquefaction refers to a condition where vibration or shaking of the ground, usually during earthquakes,
causes development of excess pore water pressures in saturated soils and subsequent loss of strength in
a soil unit so affected. The increased pore water pressure may temporarily meet or exceed soil overburden
pressures to produce conditions that allow soil and water to flow, deform, or erupt from the ground surface.
Ground settlement, lateral spreading and/or sand boils may result from liquefaction. Structures, such as
buildings and other site facilities, supported on or within liquefied soils may suffer foundation settlement
February 18, 2022 | Page 6 File No. 16933-001-33
or lateral movement that can be damaging. In general, soils that are susceptible to liquefaction include
loose to medium dense sand to silty sand and soft to stiff sandy silt, which are below the groundwater level.
Based on deep explorations in the site area, the loose to medium dense sand deposits and medium stiff
sandy silt below the water table in the upper 30 to 50 feet are susceptible to liquefaction during a design
earthquake. We evaluated the liquefaction potential of the site soils using the Simplified Procedure (Idriss
and Boulanger 2008). The Simplified Procedure is based on comparing the cyclic resistance ratio (CRR) of
a soil layer (the cyclic shear stress required to cause liquefaction) to the cyclic stress ratio (CSR) induced
by an earthquake. The factor of safety against liquefaction is determined by dividing the CRR by the CSR.
Liquefaction hazards, including settlement and related effects, were evaluated when the factor of safety
against liquefaction was calculated as less than 1.
Estimated ground settlement resulting from earthquake-induced liquefaction was analyzed using empirical
procedures by Tokimatsu and Seed (1987) that relate settlement to the boring data. Liquefaction potential
of the site soils was evaluated using a peak ground acceleration adjusted for site effects, (PGAM = PGA*Fpga)
consistent with the American Society of Civil Engineers (ASCE) 7-16 approach.
Analysis of the boring data indicates that there is a potential for liquefaction within the upper sand and
sandy silt deposits. Liquefaction-induced free-field ground settlement of the potentially liquefiable zones is
estimated to be on the order of 6 to 9 inches for the design-level earthquake, with most of the settlement
occurring in the upper 30 feet. Lesser amounts of settlement from liquefaction could be experienced
after an earthquake with a magnitude less than the design-level earthquake. The magnitude of
liquefaction-induced ground settlement will vary as a function of the characteristics of the earthquake
(earthquake magnitude, location, duration and intensity) and the soil and groundwater conditions.
Liquefaction-induced settlement typically occurs in a non-uniform fashion.
We recommend that the structure be designed for life safety and prevention of collapse and that the
structural engineer evaluate the impact of the estimated liquefaction induced settlement on the integrity
of the structural components.
6.1.4. Lateral Spread and Earthquake Induced Landsliding
The site soils have a low risk of lateral spread due to the flat topography at the site and the distance from
the Green River (about 1 mile west). The site soils also have a low risk of earthquake induced landsliding
given the flat topography.
6.2. Foundations Recommendations
We recommend that the slab constructed to support the laboratory and the shallow foundation supporting
the tower be founded on an 18- and 24-inch-thick pad of properly compacted structural fill, respectively.
The zone of structural fill should extend laterally beyond the edges of the slab and foundation a horizontal
distance at least equal to the thickness of the fill or a minimum of 2 feet where possible. A representative
from our firm should observe the subgrade and excavations prior to placement of structural fill. Based on
the conditions encountered in the boring, the existing fill appears suitable provided it can be compacted to
the minimum standard following excavation.
An allowable soil bearing value of 2,500 psf may be used for the tower footing supported on a zone of
structural fill as described above. The allowable soil bearing value applies to the total of dead and long-
February 18, 2022 | Page 7 File No. 16933-001-33
term live loads and may be increased by up to one-third for wind or seismic loads. Lateral resistance for
overturning loads is provided in the following section.
A subgrade modulus of 100 pounds per cubic inch (pci) may be used for design of the structural slab. We
recommend a 4- to 6-inch-thick base course layer be placed in the upper portion of the 18-inch-thick
structural fill layer to provide uniform support.
We estimate static post-construction settlements on the order of ½ to 1 inch for foundations supported as
recommended above.
6.3. Lateral Resistance
The soil resistance available to resist lateral loads is a function of the frictional resistance which can
develop on the base of foundation elements, and the passive resistance which can develop on the face of
below-grade elements of the structure as these elements tend to move into the soil. Passive resistance
should be evaluated using an equivalent fluid density of 300 pcf where footings are surrounded by
structural fill compacted to at least 95 percent of MDD, as recommended. The structural fill should extend
out from the face of the foundation for a distance equal to at least two and one-half times the depth of the
foundation element. The passive resistance should be reduced to 225 pcf if the footing is poured directly
against existing fill or if the zone of structural fill does not extend out the distance specified above. These
values also assume the ground surface in front of the footing will be level for a horizontal distance equal to
at least two times the depth of the footing. If soils adjacent to footings are disturbed during construction,
the disturbed soils must be recompacted, otherwise the lateral passive resistance value must be reduced.
Resistance to passive pressure should be calculated from the bottom of adjacent paving, or below a depth
of 1 foot where the adjacent area is unpaved. Frictional resistance can be evaluated using 0.4 for the
coefficient of base friction against footings which are underlain by structural fill. The above passive
resistance and coefficient of friction values incorporate a factor of safety of about 1.5.
6.4. Earthwork
6.4.1. Excavation Considerations
Shallow excavations will likely encounter medium dense to dense fill consisting of silty sand with gravel.
We anticipate these soils can be excavated with conventional excavation equipment, such as trackhoes or
dozers. Debris, cobbles and/or boulders may be encountered where fill soils are present, and the contractor
should be prepared to deal with these during construction.
6.4.2. Subgrade Preparation
Based on the block footing depth and recommended 2-foot excavation for foundation support, we
anticipate that groundwater may be encountered at the base of the excavation if construction occurs during
the wet season. We anticipate that the groundwater can be handled during construction by sump pumping,
as necessary. All collected water should be routed to suitable discharge points.
6.4.3. Temporary Soil Cut Slopes
All temporary cut slopes must comply with the provisions of Title 296 Washington Administrative Code
(WAC), Part N, “Excavation, Trenching and Shoring.” The contractor performing the work has the primary
responsibility for protection of workers and adjacent improvements.
February 18, 2022 | Page 8 File No. 16933-001-33
We recommend temporary cut slope inclinations of 1H:1V (horizontal to vertical) in the existing fill and
1.5H:1V in the underlying alluvial deposits. Some caving/sloughing of the cut slopes may occur at this
inclination. The inclination may need to be flattened by the contractor if significant caving/sloughing occurs.
These cut slope recommendations apply to fully dewatered conditions. For open cuts at the site, we
recommend that:
■ No traffic, construction equipment, stockpiles or building supplies be allowed at the top of the cut
slopes within a distance of at least 5 feet from the top of the cut;
■ Exposed soil along the slope be protected from surface erosion using waterproof tarps or plastic
sheeting;
■ Construction activities be scheduled so that the length of time the temporary cut is left open is reduced
to the extent practicable;
■ Erosion control measures be implemented as appropriate such that runoff from the site is reduced to
the extent practicable;
■ Surface water be diverted away from the excavation; and
■ The general condition of the slopes be observed periodically by GeoEngineers to confirm adequate
stability.
Because the contractor has control of the construction operations, the contractor should be made
responsible for the stability of cut slopes, as well as the safety of the excavations. The contractor should
take all necessary steps to ensure the safety of the workers near slopes.
6.4.4. Structural Fill
Fill placed to support structures, pavements and sidewalks is specified as structural fill as described below:
■ All fill placed to achieve slab grade, backfill utility trenches, and under footings should be placed as
structural fill. Where import fill is required, we recommend the fill consist of gravel borrow as specified
in Section 9-03.14(1) of the 2022 Washington State Department of Transportation (WSDOT) Standard
Specifications, with the additional restriction that the fines content be limited to no more than 5 percent
if placed during wet weather. The on-site soils contain greater fines content. These soils will be suitable
during dry conditions provided they can be compacted to the minimum standard.
■ Structural fill placed as crushed surfacing base course below pavements should conform to
Section 9-03.9(3) of the 2022 WSDOT Standard Specifications.
■ Bedding for utilities should conform to Section 9-03.12(3) of the 2022 WSDOT Standard Specifications.
6.4.4.1. Fill Placement and Compaction Criteria
Structural fill should be placed in loose lifts not exceeding 12 inches in thickness. Each lift should be
conditioned to the proper moisture content and compacted to the specified density before placing
subsequent lifts. Structural fill should be compacted to the following criteria:
■ Structural fill placed below the slab and tower foundation should be compacted to 95 percent of the
MDD estimated in general accordance with ASTM International (ASTM) D 1557.
February 18, 2022 | Page 9 File No. 16933-001-33
■ Structural fill placed in pavement or sidewalk areas, including utility trench backfill, should be
compacted to 90 percent of the MDD estimated in general accordance with ASTM D 1557, except that
the upper 2 feet of fill below final subgrade should be compacted to 95 percent of the MDD.
■ Structural fill placed as crushed rock base course below pavements should be compacted to
95 percent of the MDD estimated in general accordance with ASTM D1557.
We recommend that a representative from our firm be present during placement of structural fill. Our
representative will evaluate the adequacy of the subgrade soils and identify areas needing further work,
perform in-place moisture-density tests in the fill to evaluate if the work is being done in accordance with
the compaction specifications, and advise on any modifications to procedure that may be appropriate for
the prevailing conditions.
6.4.1. On-site Soils
We anticipate that the on-site existing fill soils range from crushed rock to sand and gravel with variable silt
content. The existing fill soils may require moisture-conditioning in order to meet the required compaction
criteria. Because of the fines content, existing fill will only be suitable for reuse during dry weather following
moisture conditioning. Any excavated fill or native soils consisting of silt will not be suitable for reuse as
structural fill.
6.4.2. Utility Considerations
In general, trench excavation, pipe bedding, and trench backfilling should be completed using the general
procedures described in Section 7 of the 2022 WSDOT Standard Specifications or other suitable
procedures specified by the project civil engineer.
Utility pipes should be bedded in sand and/or smooth rounded gravel, such as specified in WSDOT Standard
Specification 9-03.12.(3). Additionally, we recommend that the pipe be covered with bedding material to
at least 1 foot above the pipe. This bedding material should be lightly tamped into place. Backfill placed
above the bedding material shall consist of structural fill quality material as discussed in Section 5.3.4.
7.0 LIMITATIONS
We have prepared this report for the exclusive use of Blue Origin LLC. and their authorized agents for the
proposed Fuel Cell Test Laboratory – DaVinci Laboratory in Renton, Washington. The data and report should
be provided to prospective contractors for their bidding or estimating purposes, but our report, conclusions
and interpretations should not be construed as a warranty of the subsurface conditions.
Within the limitations of scope, schedule and budget, our services have been executed in accordance with
generally accepted practices in the field of geotechnical engineering in this area at the time this report was
prepared. No warranty or other conditions, express or implied, should be understood.
Please refer to Appendix D, Report Limitations and Guidelines for Use, for additional information pertaining
to use of this report.
February 18, 2022 | Page 10 File No. 16933-001-33
8.0 REFERENCES
Applied Technology Council, “Hazards by Location, Seismic” accessed via: https://hazards.atcouncil.org/#/
on February 14, 2022.
Booth, D.B, Troost, K.A,, and Wisher, A. P. 2007. “Geologic Map of King County.”
GeoEngineers, Inc., 2000, “Report, Geotechnical Engineering Services, Renton Switching Facility, Renton,
Washington,” dated January 27, 2000.
Idriss, I.M. and Boulanger, R.W. (2008), “Soil Liquefaction During Earthquakes.” Earthquake Engineering
Research Institute (EERI), Monograph MNO-12.
International Building Code, 2018, “International Building Code.”
Tokimatsu, K. and Seed, H.B. (1987). “Evaluation of Settlement in Sands due to Earthquake Shaking,”
Journal of Geotechnical Engineering, ASCE, Vol. 113, No. 8, August 1987, pp. 861-878.
Washington Administrative Code (WAC), Title 296, Part N, “Excavation, Trenching and Shoring.”
Washington State Department of Transportation, 2022, “Standard Specifications for Road, Bridge and
Municipal Construction.”
FIGURES
Spri
ngbrookCr
eekS W 1 6th St
Boeing
Longacres
Industrial Park
SW 5 t h P lShattuckAveSSW 7th St S 7th St
167
Sprin
g
b
r
ookCreekPa nther Creek ShattuckAveSPowellAveSWLindAveSWS 1 4 t h S t
SW 19th St
S W 1 0 t h S t
RaymondAveSWSW 16th St
OakesdaleAveSWS W G r a d y W a y
167
405
Lower Talbot
Hill Park
Lake Street
Park
S 5th St
S 6th St
S G radyW ayTalbotRdSMorrisAveS515
Thomas
Teasdale Park
SITE
Vicinity Map
Figure 1
Fuel Cell Test Laboratory – DaVinci Laboratory
Renton, Washington
3
Alpine Lakes
Wilderness
Kent
Tacoma
Seattle
1,000 1,0000
Feet
Data Source: ESRI
Notes:
1. The locations of all features shown are approximate.2. This drawing is for information purposes. It is intended to assist inshowing features discussed in an attached document. GeoEngineers, Inc.cannot guarantee the accuracy and content of electronic files. The masterfile is stored by GeoEngineers, Inc. and will serve as the official record ofthis communication.
Projection: NAD 1983 UTM Zone 10N
P:\16\16933001\GIS\16933001_Project\16933001_Project.aprx\1693300133_F01_VM Date Exported: 01/19/22 by ccabrera
Highway 405
Maple Ave SWB-1
TP-5 B-2
TP-2
TP-6
TP-4
TP-3
B-1
TP-1
Figure 2
Fuel Cell Test Laboratory - DaVinci Laboratory
Renton, Washington
Site Plan
P:\16\16933001\CAD\33\Geotech Report\1693300133_F02_Site Plan.dwg TAB:F02 Date Exported: 01/28/22 - 12:51 by gregisterB-1 Boring by GeoEngineers, Inc., 2022
W E
N
S
Notes:
1.The locations of all features shown are approximate.
2.This drawing is for information purposes. It is intended to assist in showing
features discussed in an attached document. GeoEngineers, Inc. cannot
guarantee the accuracy and content of electronic files. The master file is stored
by GeoEngineers, Inc. and will serve as the official record of this communication.
Data Source: Background from Huitt-Zollars dated 01/25/2022.
Projection: Washington State Plane, North Zone, NAD83, US Foot
Feet
0
Legend
40 40
Proposed Testing Lab
Proposed 20-Foot Tall Tower
B-1 Boring by GeoEngineers, Inc., 2000
TP-1 Test Pit by GeoEngineers, Inc., 1991
APPENDICES
APPENDIX A Field Explorations
February 18, 2022 | Page A-1 File No. 16933-001-33
APPENDIX A
FIELD EXPLORATIONS
We explored subsurface soil and groundwater conditions at the site by advancing one boring, B-1, to a
depth of 51.5 feet on January 17, 2022. The boring was drilled at the approximate location shown in Figure
2 using track-mounted equipment owned and operated by Advance Drill Technologies, Inc.
The boring was continuously monitored by a geotechnical engineer from our firm who examined and
classified the soils encountered, obtained representative soil samples, and observed groundwater
conditions. Our representative maintained a detailed log of the boring. Disturbed samples of the
representative soil types were obtained using a 2-inch outside diameter standard penetration test (SPT)
split-spoon sampler.
The soils encountered in the test boring were typically sampled at 2.5-foot vertical intervals for the first 10-
and 5-foot vertical intervals for the remaining depth with the SPT split-spoon sampler through the full depth
of the explorations. SPT samples were driven with a standard 140-pound hammer in accordance with ASTM
International (ASTM) D 1586. During the test, a sample is obtained by driving the sampler 18 inches into
the soil with a hammer free-falling 30 inches. The number of blows required for each 6 inches of penetration
is recorded. The Standard Penetration Resistance (“N-value”) of the soil is calculated as the number of
blows required for the final 12 inches of penetration (blows per foot). This resistance, or N-value, provides
a measure of the relative density of granular soils and the relative consistency of cohesive soils.
Soils encountered in the boring were visually classified in general accordance with the system described in
Figure A-1. A key to the boring log symbols is also presented in Figure A-1. A log of the boring is presented
in Figure A-2. The exploration log is based on our interpretation of the field and laboratory data and indicate
the various types of soils and groundwater conditions encountered. They also indicate the depths at which
these soils or their characteristics change, although the change might actually be gradual. If the change
occurred between samples, it was interpreted. The SPT boring was backfilled in general accordance with
procedures outlined by the Washington State Department of Ecology.
Measured groundwater level in exploration,well, or piezometer
Measured free product in well or piezometer
Distinct contact between soil strata
Approximate contact between soil strata
Contact between geologic units
SYMBOLS TYPICAL
DESCRIPTIONS
GW
GP
SW
SP
SM
FINEGRAINED
SOILS
SILTS ANDCLAYS
NOTE: Multiple symbols are used to indicate borderline or dual soil classifications
MORE THAN 50%RETAINED ONNO. 200 SIEVE
MORE THAN 50%PASSINGNO. 200 SIEVE
GRAVEL
ANDGRAVELLYSOILS
SC
LIQUID LIMITLESS THAN 50
(APPRECIABLE AMOUNTOF FINES)
(APPRECIABLE AMOUNTOF FINES)
COARSEGRAINEDSOILS
MAJOR DIVISIONS GRAPH LETTER
GM
GC
ML
CL
OL
SILTS AND
CLAYS
SANDS WITHFINES
SANDANDSANDY
SOILS
MH
CH
OH
PT
(LITTLE OR NO FINES)
CLEAN SANDS
GRAVELS WITHFINES
CLEAN GRAVELS
(LITTLE OR NO FINES)
WELL-GRADED GRAVELS, GRAVEL -SAND MIXTURES
CLAYEY GRAVELS, GRAVEL - SAND -CLAY MIXTURES
WELL-GRADED SANDS, GRAVELLYSANDS
POORLY-GRADED SANDS, GRAVELLYSAND
SILTY SANDS, SAND - SILT MIXTURES
CLAYEY SANDS, SAND - CLAYMIXTURES
INORGANIC SILTS, ROCK FLOUR,CLAYEY SILTS WITH SLIGHTPLASTICITY
INORGANIC CLAYS OF LOW TOMEDIUM PLASTICITY, GRAVELLYCLAYS, SANDY CLAYS, SILTY CLAYS,LEAN CLAYS
ORGANIC SILTS AND ORGANIC SILTYCLAYS OF LOW PLASTICITY
INORGANIC SILTS, MICACEOUS ORDIATOMACEOUS SILTY SOILS
INORGANIC CLAYS OF HIGHPLASTICITY
ORGANIC CLAYS AND SILTS OFMEDIUM TO HIGH PLASTICITY
PEAT, HUMUS, SWAMP SOILS WITHHIGH ORGANIC CONTENTSHIGHLY ORGANIC SOILS
SOIL CLASSIFICATION CHART
MORE THAN 50%OF COARSEFRACTION RETAINEDON NO. 4 SIEVE
MORE THAN 50%OF COARSEFRACTION PASSINGON NO. 4 SIEVE
SILTY GRAVELS, GRAVEL - SAND -SILT MIXTURES
POORLY-GRADED GRAVELS,GRAVEL - SAND MIXTURES
LIQUID LIMIT GREATERTHAN 50
Continuous Coring
Bulk or grab
Direct-Push
Piston
Shelby tube
Standard Penetration Test (SPT)
Contact between soil of the same geologicunit
Material Description Contact
Graphic Log Contact
NOTE: The reader must refer to the discussion in the report text and the logs of explorations for a proper understanding of subsurface conditions.Descriptions on the logs apply only at the specific exploration locations and at the time the explorations were made; they are not warranted to berepresentative of subsurface conditions at other locations or times.
Groundwater Contact
Blowcount is recorded for driven samplers as the number ofblows required to advance sampler 12 inches (or distance noted).See exploration log for hammer weight and drop.
"P" indicates sampler pushed using the weight of the drill rig.
"WOH" indicates sampler pushed using the weight of thehammer.
Key to Exploration Logs
Figure A-1
Sampler Symbol Descriptions
ADDITIONAL MATERIAL SYMBOLS
SYMBOLS
Asphalt Concrete
Cement Concrete
Crushed Rock/Quarry Spalls
Topsoil
GRAPH LETTER
AC
CC
SOD Sod/Forest Duff
CR
DESCRIPTIONS
TYPICAL
TS
No Visible SheenSlight SheenModerate SheenHeavy Sheen
Laboratory / Field Tests
2.4-inch I.D. split barrel / Dames & Moore (D&M)
%F%GALCACPCSDDDSHAMCMDMohsOCPMPIPLPPSATXUCUUVS
Sheen Classification
NSSSMSHS
Percent finesPercent gravelAtterberg limitsChemical analysisLaboratory compaction testConsolidation testDry densityDirect shearHydrometer analysisMoisture contentMoisture content and dry densityMohs hardness scaleOrganic contentPermeability or hydraulic conductivityPlasticity indexPoint lead testPocket penetrometerSieve analysisTriaxial compressionUnconfined compressionUnconsolidated undrained triaxial compressionVane shear
Rev 01/2022
Attempted to push Shelby tube; Shelby tubecollapsed, no recoveryGroundwater observed at approximately 5½ feetat time of drilling
Driller started adding mud to control heave
Very easy drilling
Moderate drill chatter
15
5
5
50
7
6
9
15
13
28
45
9
10
Approximately 4 inches of asphalt concrete pavement
Gray silty fine to coarse sand with gravel (mediumdense, moist) (fill)
Gray silty fine to coarse sand with gravel (dense,moist)
Gray silty fine to coarse sand with gravel (dense, wet)
Gray fine to coarse sand with gravel (medium dense,wet) (alluvium)
Gray fine to medium sand with occasional organicmatter (loose, wet)
Grayish brown sandy silt (medium stiff, wet)
Gray well-graded fine to coarse gravel with silt andsand (dense, wet)
Gray fine to coarse sand with silt and gravel (mediumdense to very dense, wet)
1
2SA
3MC
4SA
5
6%F
7%F
8SA
9SA
6
18
7
18
18
18
18
8
16
30
40
19
16
5
5
34
28
AC
SM
SM
SM
SP
SP
ML
GW-GM
SP-SM
Notes:
51.5 JQS
CWM Advance Drill Technologies,Inc.Hollow-stem Auger
Deidrich D-50 TurboDrillingEquipmentAutohammer140 (lbs) / 30 (in) Drop
WA State Plane NorthNAD83 (feet)1296805173547
20NAVD88
Easting (X)Northing (Y)
Start TotalDepth (ft)
Logged By
Checked By
End
Surface Elevation (ft)Vertical Datum
Drilled
HammerData
SystemDatum
Driller DrillingMethod
See "Remarks" section for groundwater observed
1/17/20221/17/2022
Note: See Figure A-1 for explanation of symbols.Coordinates Data Source: Horizontal approximated based on Site Survey. Vertical approximated based on Google Earth.
Sheet 1 of 2Project Number:
Project Location:
Project:
16933-001-33
Log of Boring B-1
Figure 2
Fuel Cell Test Laboratory - DaVinci Laboratory
Renton, Washington
Date:2/16/22 Path:\\GEOENGINEERS.COM\WAN\PROJECTS\16\16933001\GINT\1693300133.GPJ DBLibrary/Library:GEOENGINEERS_DF_STD_US_JUNE_2017.GLB/GEI8_GEOTECH_STANDARD_%F_NO_GWREMARKS
FinesContent (%)MoistureContent (%)FIELD DATA
MATERIALDESCRIPTION
Sample NameTestingRecovered (in)IntervalBlows/footCollected SampleDepth (feet)0
5
10
15
20
25
30
35 Graphic LogGroupClassificationElevation (feet)151050-5-10-15
6
4
12
16
Gray fine to medium sand with occasional gravel(dense, wet)
10SA
11
12
13%F
10
18
18
18
35
26
50
42
SP
Sheet 2 of 2Project Number:
Project Location:
Project:
16933-001-33
Log of Boring B-1 (continued)
Figure 2
Fuel Cell Test Laboratory - DaVinci Laboratory
Renton, Washington
Date:2/16/22 Path:\\GEOENGINEERS.COM\WAN\PROJECTS\16\16933001\GINT\1693300133.GPJ DBLibrary/Library:GEOENGINEERS_DF_STD_US_JUNE_2017.GLB/GEI8_GEOTECH_STANDARD_%F_NO_GWREMARKS
FinesContent (%)MoistureContent (%)FIELD DATA
MATERIALDESCRIPTION
Sample NameTestingRecovered (in)IntervalBlows/footCollected SampleDepth (feet)35
40
45
50 Graphic LogGroupClassificationElevation (feet)-20-25-30
APPENDIX B Laboratory Testing
February 18, 2022 | Page B-1 File No. 16933-001-33
APPENDIX B
LABORATORY TESTING
Soil samples obtained from the boring were transported to our laboratory and evaluated to confirm or
modify field classifications, as well as to evaluate engineering properties of the soil samples.
Representative samples were selected for laboratory testing consisting of moisture content testing, percent
fines (material passing the U.S. No. 200 sieve) evaluation, and sieve analysis. The tests were performed in
general accordance with test methods of the ASTM International (ASTM) or other applicable procedures.
Moisture Content
Moisture contents were completed in general accordance with ASTM D 2216 and D 2937 for representative
samples obtained. The results of these tests are presented on the exploration log in Appendix A at the
depths at which the samples were obtained.
Percent Passing U.S. No. 200 Sieve (%F)
Selected samples were “washed” through the No. 200 mesh sieve to estimate the relative percentages of
coarse and fine-grained particles in the soil. The percent passing value represents the percentage by weight
of the sample finer than the U.S. No. 200 sieve. These tests were conducted to verify field descriptions
and to estimate the fines content for analysis purposes. The tests were conducted in accordance with
ASTM D 1140, and the results are shown on the exploration log at the respective sample depths.
Sieve Analyses
Sieve analyses were performed on selected samples in general accordance with ASTM C 136. The wet sieve
analysis method was used to determine the percentage of soil greater than the U.S. No. 200 mesh sieve.
Results of the sieve analyses are presented in Figures B-1 and B-2.
0
10
20
30
40
50
60
70
80
90
100
0.0010.010.11101001000PERCENT PASSING BY WEIGHT GRAIN SIZE IN MILLIMETERS
U.S. STANDARD SIEVE SIZE
2”
SAND SILT OR CLAYCOBBLESGRAVEL
COARSE MEDIUM FINECOARSEFINE
Boring Number
Depth
(feet)Soil Description
B-1
B-1
B-1
B-1
2.5
7.5
25
30
Silty fine to coarse sand with gravel (SM)
Fine to coarse sand with gravel (SP)
Well-graded fine to coarse gravel with silt and sand (GW-GM)
Fine to coarse sand with silt and gravel (SP-SM)
Symbol
Moisture
(%)
9
13
9
10
3/8”3”1.5”#4 #10 #20 #40 #60 #1003/4”Figure B-1Sieve Analysis ResultsFuel Cell Test Laboratory –DaVinci Laboratory Renton, Washington 16933-001-33 Date Exported: 01/28/2022
Note:This report may not be reproduced,except in full,without written approval of GeoEngineers,Inc.Test results are applicable only to the specific sample on which they were
performed,and should not be interpretedas representativeof any other samples obtainedat othertimes,depths or locations,or generatedby separate operations orprocesses.
Thegrain size analysis results wereobtainedingeneral accordancewith ASTM C136.GeoEngineers 17425NE UnionHillRoad Ste 250,Redmond,WA 98052
#2001”#140
0
10
20
30
40
50
60
70
80
90
100
0.0010.010.11101001000PERCENT PASSING BY WEIGHT GRAIN SIZE IN MILLIMETERS
U.S. STANDARD SIEVE SIZE
2”
SAND SILT OR CLAYCOBBLESGRAVEL
COARSE MEDIUM FINECOARSEFINE
Boring Number
Depth
(feet)Soil Description
B-1 35 Fine to coarse sand with silt and gravel (SP-SM)
Symbol
Moisture
(%)
12
3/8”3”1.5”#4 #10 #20 #40 #60 #1003/4”Figure B-2Sieve Analysis ResultsFuel Cell Test Laboratory –DaVinci Laboratory Renton, Washington 16933-001-33 Date Exported: 01/28/2022
Note:This report may not be reproduced,except in full,without written approval of GeoEngineers,Inc.Test results are applicable only to the specific sample on which they were
performed,and should not be interpretedas representativeof any other samples obtainedat othertimes,depths or locations,or generatedby separate operations orprocesses.
Thegrain size analysis results wereobtainedingeneral accordancewith ASTM C136.GeoEngineers 17425NE UnionHillRoad Ste 250,Redmond,WA 98052
#2001”#140
APPENDIX C Previous Explorations
APPENDIX D Report Limitations and Guidelines for Use
February 18, 2022 | Page D-1 File No. 16933-001-33
APPENDIX D
REPORT LIMITATIONS AND GUIDELINES FOR USE1
This appendix provides information to help you manage your risks with respect to the use of this report.
Geotechnical Services Are Performed for Specific Purposes, Persons and Projects
This report has been prepared for the exclusive use of Blue Origin LLC and their authorized agents. This
report may be made available to prospective contractors for their bidding or estimating purposes, but our
report, conclusions and interpretations should not be construed as a warranty of the subsurface conditions.
This report is not intended for use by others, and the information contained herein is not applicable to other
sites.
GeoEngineers structures our services to meet the specific needs of our clients. For example, a geotechnical
or geologic study conducted for a civil engineer or architect may not fulfill the needs of a construction
contractor or even another civil engineer or architect that are involved in the same project. Because each
geotechnical or geologic study is unique, each geotechnical engineering or geologic report is unique,
prepared solely for the specific client and project site. Our report is prepared for the exclusive use of our
Client. No other party may rely on the product of our services unless we agree in advance to such reliance
in writing. This is to provide our firm with reasonable protection against open-ended liability claims by third
parties with which there would otherwise be no contractual limits to their actions. Within the limitations of
scope, schedule and budget, our services have been executed in accordance with our Agreement with the
Client and generally accepted geotechnical practices in this area at the time this report was prepared. This
report should not be applied for any purpose or project except the one originally contemplated.
A Geotechnical Engineering or Geologic Report Is Based on a Unique Set of Project-Specific
Factors
This report has been prepared for the Fuel Cell Test Laboratory – DaVinci Laboratory project in
Renton, Washington. GeoEngineers considered a number of unique, project-specific factors when
establishing the scope of services for this project and report. Unless GeoEngineers specifically indicates
otherwise, do not rely on this report if it was:
■ Not prepared for you,
■ Not prepared for your project,
■ Not prepared for the specific site explored, or
■ Completed before important project changes were made.
For example, changes that can affect the applicability of this report include those that affect:
■ The function of the proposed structure;
■ Elevation, configuration, location, orientation or weight of the proposed structure;
1 Developed based on material provided by ASFE, Professional Firms Practicing in the Geosciences; www.asfe.org .
February 18, 2022 | Page D-2 File No. 16933-001-33
■ Composition of the design team; or
■ Project ownership.
If important changes are made after the date of this report, GeoEngineers should be given the opportunity
to review our interpretations and recommendations and provide written modifications or confirmation, as
appropriate.
Subsurface Conditions Can Change
This geotechnical or geologic report is based on conditions that existed at the time the study was performed.
The findings and conclusions of this report may be affected by the passage of time, by manmade events
such as construction on or adjacent to the site, or by natural events such as floods, earthquakes, slope
instability or groundwater fluctuations. Always contact GeoEngineers before applying a report to determine
if it remains applicable.
Most Geotechnical and Geologic Findings Are Professional Opinions
Our interpretations of subsurface conditions are based on field observations from widely spaced sampling
locations at the site. Site exploration identifies subsurface conditions only at those points where subsurface
tests are conducted or samples are taken. GeoEngineers reviewed field and laboratory data and then
applied our professional judgment to render an opinion about subsurface conditions throughout the site.
Actual subsurface conditions may differ, sometimes significantly, from those indicated in this report. Our
report, conclusions and interpretations should not be construed as a warranty of the subsurface conditions.
Geotechnical Engineering Report Recommendations Are Not Final
Do not over-rely on the preliminary construction recommendations included in this report. These
recommendations are not final, because they were developed principally from GeoEngineers’ professional
judgment and opinion. GeoEngineers’ recommendations can be finalized only by observing actual
subsurface conditions revealed during construction. GeoEngineers cannot assume responsibility or liability
for this report's recommendations if we do not perform construction observation.
Sufficient monitoring, testing and consultation by GeoEngineers should be provided during construction to
confirm that the conditions encountered are consistent with those indicated by the explorations, to provide
recommendations for design changes should the conditions revealed during the work differ from those
anticipated, and to evaluate whether or not earthwork activities are completed in accordance with our
recommendations. Retaining GeoEngineers for construction observation for this project is the most
effective method of managing the risks associated with unanticipated conditions.
A Geotechnical Engineering or Geologic Report Could Be Subject to Misinterpretation
Misinterpretation of this report by other design team members can result in costly problems. You could
lower that risk by having GeoEngineers confer with appropriate members of the design team after
submitting the report. Also retain GeoEngineers to review pertinent elements of the design team's plans
and specifications. Contractors can also misinterpret a geotechnical engineering or geologic report. Reduce
that risk by having GeoEngineers participate in pre-bid and preconstruction conferences, and by providing
construction observation.
February 18, 2022 | Page D-3 File No. 16933-001-33
Do Not Redraw the Exploration Logs
Geotechnical engineers and geologists prepare final boring and testing logs based upon their interpretation
of field logs and laboratory data. To prevent errors or omissions, the logs included in a geotechnical
engineering or geologic report should never be redrawn for inclusion in architectural or other design
drawings. Only photographic or electronic reproduction is acceptable, but recognize that separating logs
from the report can elevate risk.
Give Contractors a Complete Report and Guidance
Some owners and design professionals believe they can make contractors liable for unanticipated
subsurface conditions by limiting what they provide for bid preparation. To help prevent costly problems,
give contractors the complete geotechnical engineering or geologic report, but preface it with a clearly
written letter of transmittal. In that letter, advise contractors that the report was not prepared for purposes
of bid development and that the report's accuracy is limited; encourage them to confer with GeoEngineers
and/or to conduct additional study to obtain the specific types of information they need or prefer. A pre-bid
conference can also be valuable. Be sure contractors have sufficient time to perform additional study. Only
then might an owner be in a position to give contractors the best information available, while requiring them
to at least share the financial responsibilities stemming from unanticipated conditions. Further, a
contingency for unanticipated conditions should be included in your project budget and schedule.
Contractors Are Responsible for Site Safety on Their Own Construction Projects
Our geotechnical recommendations are not intended to direct the contractor’s procedures, methods,
schedule or management of the work site. The contractor is solely responsible for job site safety and for
managing construction operations to minimize risks to on-site personnel and to adjacent properties.
Read These Provisions Closely
Some clients, design professionals and contractors may not recognize that the geoscience practices
(geotechnical engineering or geology) are far less exact than other engineering and natural science
disciplines. This lack of understanding can create unrealistic expectations that could lead to
disappointments, claims and disputes. GeoEngineers includes these explanatory “limitations” provisions in
our reports to help reduce such risks. Please confer with GeoEngineers if you are unclear how these “Report
Limitations and Guidelines for Use” apply to your project or site.
Geotechnical, Geologic and Environmental Reports Should Not Be Interchanged
The equipment, techniques and personnel used to perform an environmental study differ significantly from
those used to perform a geotechnical or geologic study and vice versa. For that reason, a geotechnical
engineering or geologic report does not usually relate any environmental findings, conclusions or
recommendations; e.g., about the likelihood of encountering underground storage tanks or regulated
contaminants. Similarly, environmental reports are not used to address geotechnical or geologic concerns
regarding a specific project.
February 18, 2022 | Page D-4 File No. 16933-001-33
Biological Pollutants
GeoEngineers’ Scope of Work specifically excludes the investigation, detection, prevention or assessment
of the presence of Biological Pollutants. Accordingly, this report does not include any interpretations,
recommendations, findings, or conclusions regarding the detecting, assessing, preventing or abating of
Biological Pollutants and no conclusions or inferences should be drawn regarding Biological Pollutants, as
they may relate to this project. The term “Biological Pollutants” includes, but is not limited to, molds, fungi,
spores, bacteria, and viruses, and/or any of their byproducts.
If Client desires these specialized services, they should be obtained from a consultant who offers services
in this specialized field.