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GEOTEST
Geotechnical EngineeringReport
Arlington Taco Bell
77XX 204 th Street N E
Arlington , Washington
Parcel No. 00847300000200
Client Name: Pacific Bells, LLC
Project Name: Granite Falls Taco Bell
Project Number: 00-252170-0
Date: September 30, 2025
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September 30, 2025
Project No. 10-252170-0
Pacific Bells, LLC
111 West 39m Street
Vancouver, Washington 98660
c/o: Albert Palacios
Anchor Point Management Group
Regarding: Geotechnical Engineering Report
Arlington Taco Bell
77XX 204th Street NE
Arlington, Washington
Parcel No. 00847300000200
Dear Albert:
As requested, Certerra Northwest LLC (formerly GeoTest Services, Inc.) is pleased to submit the following report
summarizing the results of our geotechnical evaluation for the proposed Taco Bell located at 77XX 20411 Street NE (Parcel
No. 00847300000200) in Arlington, Washington (see Vicinity Map, Figure 1). This report has been prepared in general
accordance with the terms and conditions established in our services agreement dated August 2711,2025 and authorized by
yourself.
We appreciate the opportunity to provide geotechnical services on this project and look forward to assisting you during the
construction phase. Should you have any further questions regarding the information contained within the report, or if we
may be of service in other regards, please contact the undersigned.
Respectfully, �00 A C
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Jeff Vanfossen Edwardo Garcia, P.E.
Geotechnical Technician Geotechnical Department Manager
Enclosure: Geotechnical Engineering Report
certerra.com 20527 6711 Avenue NE,Arlington,WA 98223 T.360.435.1141
CERTERRA
GEOTEST
TABLE OF CONTENTS
Purpose and Scope of Services.....................................................................................................................................1
ProjectDescription..........................................................................................................................................................1
SiteConditions ................................................................................................................................................................1
SurfaceConditions......................................................................................................................................................................2
SubsurfaceSoil Conditions........................................................................................................................................................2
GeneralGeologic Conditions.....................................................................................................................................................2
Groundwater.................................................................................................................................................................................3
WebSoil Survey..........................................................................................................................................................................4
GeologicHazards............................................................................................................................................................4
Seismic and Liquefaction Hazards............................................................................................................................................4
Conclusions and Recommendations .............................................................................................................................5
SitePreparation and Earthwork.................................................................................................................................................6
Filland Compaction.....................................................................................................................................................................6
Reuseof On-Site Soil — Existing Fill .....................................................................................................................................6
Reuseof On-Site Soil — Native Soil......................................................................................................................................7
ImportStructural Fill...............................................................................................................................................................7
Backfilland Compaction........................................................................................................................................................7
WetWeather Earthwork..............................................................................................................................................................7
SeismicDesign Considerations.................................................................................................................................................8
FoundationSupport.....................................................................................................................................................................8
Limited Overexcavation and Replacement..........................................................................................................................8
AllowableBearing Capacity...................................................................................................................................................8
FoundationSettlement...........................................................................................................................................................9
FloorSupport...............................................................................................................................................................................9
Foundationand Site Drainage...................................................................................................................................................9
Resistanceto Lateral Loads.....................................................................................................................................................10
Temporaryand Permanent Slopes.........................................................................................................................................10
Utilities.........................................................................................................................................................................................11
Pavement Subgrade Preparation............................................................................................................................................11
Light-Duty Flexible Pavement.............................................................................................................................................11
Heavy-Duty Flexible Pavement...........................................................................................................................................12
ConcretePavement..............................................................................................................................................................12
Stormwater Infiltration Potential ..............................................................................................................................................12
StormwaterTreatment.........................................................................................................................................................12
Geotechnical Consultation and Construction Monitoring ....................................................................................................13
Useof This Report.........................................................................................................................................................13
References.....................................................................................................................................................................14
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Purpose and Scope of Services
The purpose of this evaluation is to establish general subsurface conditions beneath the site from which conclusions and
recommendations pertaining to project design can be formulated. Our scope of services includes the following tasks:
• Exploration of soil and groundwater conditions underlying the site by advancing five Test Pit Explorations (TP-1
through TP-5)with a subcontracted tracked excavator to evaluate subsurface conditions.
• Perform a visual reconnaissance of the proposed development site and immediate vicinity to observe existing site
topographic and geologic conditions.
• Laboratory testing on representative samples to classify and evaluate the engineering characteristics of the soils
encountered.
• Provide a preliminary assessment of the on-site infiltration capability based on USDA textural classification and the
Stormwater Management Manual for Western Washington[Manual].
• Provide a written report containing a description of surface and subsurface conditions and exploration logs. Included
are findings and recommendations pertaining to site preparation and earthwork, including stripping depths,
subgrade preparation below the planned buildings, reuse of on-site soils, wet weather earthwork, and criteria for
selection, placement, and compaction of Structural Fill.
• Provide recommendations for foundation support of the planned structures including allowable bearing pressures,
bearing elevations, frost penetration depth, a discussion of potential foundation settlement (total and differential),
floor support, and general foundation design.
• Provide recommendations for lateral earth pressures including active and at-rest conditions, allowable passive soil
resistance, groundwater considerations, drainage recommendations, temporary and permanent slope inclinations,
and utilities.
• A discussion of the Seismic Site Class considerations based on the 2021 International Building Code (IBC).
• Provide an assessment of geologically hazardous areas per the City of Arlington Municipal Code (AMC), Chapter
20.93.600, Geologically Hazardous Areas.
• Provide recommendations for geotechnical monitoring, materials testing, and consultation during construction.
Project Description
We understand that there are plans to construct a new one-story Taco Bell restaurant with a drive-through and typical
parking/drive paths. Certerra anticipates that the new construction will utilize typical wood-framed construction with slab-
on-grade floors. Structural loads have not been provided to us but are expected to be relatively light and will utilize shallow
conventional foundations. Certerra does not expect that significant grading will be required to achieve final site grades.
A stormwater plan was not available at the time of this report. The infiltration of stormwater is expected as a project goal and
preliminary infiltration feasibility information is outlined later in this report.
Site Conditions
This section includes a description of the general surface and subsurface conditions observed at the project site during the
time of our field investigation. Interpretations of site conditions are based on the results and review of available information,
site reconnaissance, subsurface explorations, laboratory testing, and previous experience in the project vicinity.
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Surface Conditions
The project consists of one parcel (No. 00847300000200), 0.63-acres in size, just east of 7715 2041h Street NE Street in
Arlington, Washington. The project area is currently vacant and consists of a grassy field with occasional invasive weeds.
The subject parcel is generally flat with less than a few feet of topographic relief across the site. Similarly sized commercial
developments are to the east and west of the project area, while a large residential apartment complex is present to the
north and smaller single-family residences exist to the south.
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Images 1 (left)and 2(right): Surface conditions in the northern portion of the subject parcel and excavator used for Test Pit
excavations (Image 1 —facing north)and surface conditions in the southern portion of the subject parcel (Image 2—facing southeast).
Photos 1 and 2 were taken during our initial site visit on September 101h,2025.
Subsurface Soil Conditions
Subsurface conditions were explored by advancing five test pits (TP-1 through TP-5) with a subcontracted excavator and
operator on September 10th, 2025. The explorations were advanced to depths of between 10 and 12 feet below ground
surface (BGS). Approximate locations of these explorations have been plotted on the Site and Exploration Plan (Figure 2).
The on-site subsurface soils consisted of approximately 0.25 to 1 foot of Topsoil, which was comprised of loose, brown,
moist, gravelly, very silty sand with numerous organics. Underlying the topsoil at all locations, Certerra observed
Uncontrolled Fill to depths between approximately 3 and 5.25 feet BGS. The Uncontrolled Fill consisted of loose to medium
dense, light brown to brown, dry to damp, gravelly, very silty sand with orange mottling and occasional organics. In TP-2,
between 2.25 feet and 5.25 feet BGS, the Uncontrolled Fill consisted of dense, brown, moist, sandy gravels with trace
cobbles. Beneath the Uncontrolled Fill in all exploration locations, the soils consisted of loose/stiff, brown to dark brown,
damp, silty sands/sandy silts with orange mottling. Certerra interpreted these soils as Weathered Marysville Sand.
Unweathered Marysville Sand was encountered between depths of approximately 5 feet and 7 feet BGS and extended to
the termination depth of each exploration.The native Marysville Sand were comprised of medium dense/stiff, brown to blue-
gray, moist, very silty sand with interbeds of silt and occasional orange mottling.
General Geologic Conditions
Geologic information for the project site was obtained from the Geologic map of the Arlington West 7.5-minute quadrangle,
Snohomish County, Washington (Minard, 1985), published by the United States Geological Survey. This map indicates that
the project site is underlain by Vashon Drift Recessional Outwash consisting of the Marysville Sand Member(map unit Qvrm).
The Marysville Sand Member consists of mostly well-drained, outwash sand with minor amounts of gravel. The older
Arlington Gravel Member(map unit Qvra) of the Vashon Drift Recessional Outwash is also mapped northeast of the project
site, underlying the Marysville Sand. Deposits of the Arlington Gravel consist of mostly well-drained and stratified sand and
gravel deposits. Sediments of both soil types were deposited as valley fill by meltwater flowing south from the stagnating
and receding Vashon Glacier during the Pleistocene Epoch.
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Image 3(left)and Image 4(right): Subsurface conditions observed in TP-1 (left)and TP-3 (right) illustrating the Uncontrolled Fill
observed in the shallow subsurface soil conditions. Images 3 and 4 were taken on the September 101h,2025 site visit.
Our onsite explorations indicate that the encountered subsurface soil conditions are generally in accordance with the
mapped deposits. It should be noted that the published soil types are representative of regional conditions and some
variation between onsite soils and mapped geologic units should generally be anticipated. The native soils encountered in
our explorations are consistent with soils that we have encountered on nearby projects. For the purposes of this report,
Certerra has referred to the native soils as Marysville Sand.
According to the Geologic Information Portal and Dragovich et al. (2003) illustrate that the Darrington-Devils Mountain Fault
Zone and smaller Mt. Washington Fault Zone are mapped to the north of the project site approximately 10.5 miles and 7.5
miles, respectively. The Darrington-Devils Mountain Fault Zone is described as a broad, northwest-trending right-lateral to
oblique-slip fault zone and the Mt. Washington Fault Zone is described as right-lateral strike-slip antithetic faults.According
to the same resource, there are not mapped landslides or alluvial fans near the project site.
Groundwater
Groundwater associated with the regional groundwater table was not encountered during our explorations. However,
perched water conditions were encountered in our exploration locations at depths of 11 and 12 feet BGS.The perched water
was observed within the native Marysville Sand soils.
We expect perched groundwater conditions to develop at the project site during the wet season and/or following periods of
extended precipitation. Perched water conditions occur above the regional groundwater table in the unsaturated zone and
typically occur when loose, more permeable soil is underlain by denser, less permeable soil.The vertical movement of water
through loose soils is restricted once a dense or less permeable soil is encountered at depth. Perched water conditions
typically develop in the wet season (November through April) or after extended periods of rainfall.
The groundwater conditions reported on the exploration logs are for the specific locations and dates indicated and therefore
may not be indicative of other locations and/or times. Groundwater levels are variable and groundwater conditions will
fluctuate depending on local subsurface conditions, precipitation, and changes in on-site and offsite use.
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Based on a review of publicly available well log data from the Washington Department Ecology Well Log Viewer,the regional
water table in the vicinity of the project area appears to be at depths of generally 20 and 30 feet BGS in the vicinity of the
site.
Web Soil Survey
According to the United States Department of Agriculture(USDA) Natural Resource Conservation Service(NRCS) Web Soil
Survey website, one relevant soil unit is present on the subject property. Please refer to Table 1 below for general
characteristics of the mapped site soils. Based on their erosion "K" factor assigned by the NRCS, the soils present on-site
are considered to have a moderate susceptibility to erosion with a value of 0.28. The value of the erosion factor"K" ranges
from 0.02 to 0.69; the higher the value, the more susceptible the soil is to sheet and rill erosion by water. Mapped site soils
are generally consistent with the soils observed during our explorations. However, the soil's vulnerability to sheet and rill
erosion are considered low based on the gentle slope inclination that is present within the proposed area of development.
In our opinion, erosion may be managed during and following construction using conventional best management practices.
SymbolTable I - USDA NRCS Soil Classifications
Map Unit
Map Unit Name Norma loam
Soil Description Ashy loam to sandy loam
Landform Drainageways, depressions
Parent Material Alluvium
Land Capability 5w
Classification
Erosion K Factor, 0.28
Whole Soil
Geologic Hazards
As the subject property is located within the City of Arlington, Certerra reviewed Chapter 20.93 Part V (Geologically
Hazardous Areas) of the Arlington Municipal Code (AMC). Since the subject property is relatively flat with minor elevation
gradients, it is Certerra's opinion that the subject property does not contain hazards pertaining to erosion or landslides (i.e.,
not an Erosion Hazard or Steep Slope Hazard). However, the subject property is mapped as having a low to moderate
susceptibility to liquefaction. This is addressed in the next section.
Seismic and Liquefaction Hazards
Based on a review of information obtained from the Washington State Department of Natural Resources Geologic Information
Portal, the subject site is classified as having a low to moderate liquefaction susceptibility. However, this map only provides
an estimate of the likelihood that the soil will liquefy as a result of an earthquake and is meant as a general guide to delineate
areas prone to liquefaction.
Liquefaction is defined as a significant rise in porewater pressure within a soil mass caused by earthquake-induced cyclic
shaking. The shear strength of liquefiable soils is reduced during large and/or long duration earthquakes as the soil
consistency approaches that of semi-solid slurry. Liquefaction can result in significant and widespread structural damage if
not properly mitigated. Deposits of loose, granular soil below the groundwater table are most susceptible to liquefaction.
Damage caused by foundation rotation, lateral spreading, and other ground movements can result from soil liquefaction.
The site is underlain by native, medium-dense, very gravelly, sandy soils. Certerra did not encounter the regional
groundwater table during our explorations, and a review of local well log data suggests that it is more than 20 feet BGS in
the vicinity of the site. Due to these factors, it is Certerra's opinion that the potential for liquefaction underlying the subject
property is low. Thus, it is our opinion that the site does not require mitigations to address liquefaction concerns.
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Ground Response -
Liquefaction Susceptibility ---
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Moderate
Low to moderate
Low
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Very low
Bedrock Project Location
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Ice
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Image 5. Map showing liquefaction hazard susceptibility.Yellow depicts"low to moderate"susceptibility in the vicinity of the subject
property. (Source:Washington Geologic Information Portal.)
Based on our findings, we generally agree with the mapped designation. Please keep in mind that the Pacific Northwest
region is seismically active. In addition to the nearby faults discussed above, large Cascadia subduction zone earthquakes
with possible magnitudes of 8 or 9 could produce ground shaking events with the potential to significantly impact the subject
property regardless of the topography or subsurface conditions. Cascadia subduction zone earthquakes have occurred 6
times in the last 3,500 years with the most recent taking place in 1700, approximately 325 years ago. They have been
determined to have an average recurrence interval of approximately 300 to 700 years (Atwater and Haley, 1997).
Conclusions and Recommendations
Based on the evaluation of the data collected during this investigation, it is our opinion that the subsurface conditions at the
site are suitable for the proposed development, provided the recommendations contained herein are incorporated into the
project design.
As previously mentioned,the site is generally flat and is underlain by loose Uncontrolled Fill soils, medium dense Marysville
Sand with variable amounts of gravel and silty interbeds. The fill soils extended between 3 and 5.25 feet BGS in the
explorations within the vicinity of the proposed building locations. Firm and unyielding Marysville Sand soils are, in our
opinion, suitable for foundation support.
If encountered, existing fill, deleterious materials, organics, and loose/unsuitable portions of native soil (if remedial
compaction is infeasible) should be removed from areas below foundations to expose suitable undisturbed Marysville Sand.
Alternatively, foundations may be supported by Structural Fill over suitably prepared native soils.
Due to the depths of Uncontrolled Fill encountered at the project site, full removal of these soils underlying floor slabs and
pavement areas may not be financially favorable. As such, Certerra is providing a limited overexcavation and replacement
option detailed below. It should be noted that the Owner must accept that an increased risk of differential settlement,
pavement distress, and other forms of settlement induced damage may occur from the soils underlying these areas.
This report provides preliminary findings to be used for conceptual design purposes by the Stormwater Designer. Based on
the conditions encountered during our subsurface investigation, we expect that stormwater infiltration is feasible, but may
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require subsequent investigation, monitoring, and/or additional explorations to fully develop stormwater management
concepts.
Site Preparation and Earthwork
The portions of the site proposed for foundation(s),floor slabs, pavement, and/or sidewalk development should be prepared
by removing existing pavements, topsoil, deleterious material, and significant accumulations of organics. Based on our
explorations, Certerra anticipates between 3 and 5.25 feet of removal at most locations for foundation areas to expose native
Marysville Sand soils. Finished site grades have not been established, so it is currently unknown if the project will be graded
or what finished building elevations will be.
Certerra recommends that Uncontrolled Fill be removed from all foundation areas. Prior to placement of any foundation
elements or Structural Fill, the exposed subgrade under all areas to be occupied by soil-supported foundations should be
observed to confirm suitability. If found unsuitable, the subgrade soils should be recompacted to a firm and unyielding
condition. Verification of compaction can be accomplished through proof rolling with a loaded dump truck, large self-
propelled vibrating roller, or similar piece of equipment applicable to the size of the excavation. The purpose of this effort is
to identify loose or soft soil deposits so that, if feasible, the soil distributed during site work can be recompacted. Then
foundation areas may receive Structural Fill backfilled and compacted as outlined in the Fill and Compaction section of this
report.
It is Certerra's opinion that the option with the least amount of risk for post-construction settlement is to remove existing fill
from the building footprint area. Alternatively, the Owner may elect to overexcavate at least 2 feet below the planned
foundation and floor slab areas, then backfill and compact Structural Fill as outlined in the Fill and Compaction section of
this report. Prior to placement and compaction of Structural Fill,the Uncontrolled Fill soils exposed below the overexcavated
area should be compacted to firm and unyielding conditions. If these soils are unable to be compacted to a firm and
unyielding condition, then a geotextile fabric should be used to bridge the soils between the Uncontrolled Fill and new
Structural Fill.
Proof rolling should be carefully observed by qualified geotechnical personnel. Areas exhibiting significant deflection,
pumping, or over-saturation that cannot be readily compacted should be overexcavated to firm soil. Alternatively, Dynamic
Cone Penetrometers or soil probing by a qualified Certerra representative can confirm firm and unyielding conditions if a
proof roll cannot be performed. Overexcavated areas should be backfilled with compacted granular material placed in
accordance with subsequent recommendations for Structural Fill. During periods of wet weather, proof rolling could damage
the exposed subgrade. Under these conditions, qualified geotechnical personnel should observe subgrade conditions to
determine if proof rolling is feasible.
Fill and Compaction
Structural Fill used to obtain final elevations for footings and soil-supported floor slabs must be properly placed and
compacted. In most cases, suitable, non-organic, predominantly granular soil may be used for fill material provided the
material is properly moisture conditioned prior to placement and compaction, and the specified degree of compaction is
obtained. Material containing topsoil, wood, trash, organic material, or construction debris is not suitable for reuse as
Structural Fill and should be properly disposed offsite or placed in non-structural areas.
Soils containing more than approximately 5 percent fines are considered moisture sensitive and are difficult to compact to
a firm and unyielding condition when over the optimum moisture content by more than approximately 2 percent. The
optimum moisture content is that which allows the greatest dry density to be achieved at a given level of compactive effort.
Reuse of On-Site Soil—Existing Fill
Existing fill soils were observed to extend between 3 and 5.25 feet BGS in our explorations. The existing fill soils contained
indications of refuse and/or organic debris. Fill containing refuse, debris, or organics should be segregated and removed
from the site. It should be noted that the existing fill also contained elevated fines content and are considered moisture
sensitive. Silty soil should only be reused if it can be placed at or near optimum moisture contents.
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Reuse of On-Site Soil—Native Soil
It is our opinion that the native Marysville Sand is suitable for reuse as Structural Fill when placed at or near optimum
moisture contents and if allowed for in the project plans and specifications. It should be noted that the native soils contained
restrictive layers with elevated fines contents and are considered moisture sensitive. Based on our experience, it will be
difficult to achieve industry standard levels of compaction when using these soils during wet weather, wet site conditions, or
when encountering shallow perched water. As such, we recommend that these soils only be utilized as Structural Fill during
extended periods of dry weather and site conditions. We recommend that any native soils reused under structural elements
be free of significant organic content and/or other deleterious material.
We recommend that any Uncontrolled Fill soils containing deleterious material and native soils not properly moisture
conditioned, and/or any onsite soil containing significant organic content be limited to non-structural areas or be disposed
of offsite.
Import Structural Fill
Certerra recommends that imported Structural Fill consist of clean, well-graded sandy gravel, gravelly sand, or other
approved naturally occurring granular material (pit run)with at least 30 percent retained on the No.4 sieve, or a well-graded
crushed rock. Structural Fill for dry weather construction may contain up to 10 percent fines (that portion passing the U.S.
No. 200 sieve) based on the portion passing the U.S. No. 4 sieve. The use of an imported fill having more than 10 percent
fines may be feasible, but the use of these soils should generally be reviewed by the design team prior to the start of
construction.
Imported Structural Fill with less than 5 percent fines should be used during wet weather conditions. Due to wet site
conditions, soil moisture contents could be high enough that it may be difficult to compact even clean imported select
granular fill to a firm and unyielding condition. Soils with an over-optimum moisture content should be scarified and dried
back to a suitable moisture content during periods of dry weather or removed and replaced with drier Structural Fill.
Backfill and Compaction
Structural Fill should be placed in horizontal lifts. The Structural Fill must measure 8 to 10 inches in loose thickness and be
thoroughly compacted. All Structural Fill placed under load bearing areas should be compacted to at least 95 percent of the
maximum dry density,as determined using test method ASTM D1557.The top of the compacted Structural Fill should extend
outside all foundations and other structural improvements a minimum distance equal to the thickness of the fill. We
recommend that compaction be tested after placement of each lift in the fill pad.
Wet Weather Earthwork
Fine grained Uncontrolled Fill and native soils are particularly susceptible to degradation during wet weather due to the high
percentage of fines. As a result, it may be difficult to control the moisture content of site soils during the wet season. If
construction takes place during wet weather, Certerra recommends that Structural Fill consist of imported, clean, well-
graded sand or sand and gravel as described above. If fill is to be placed or earthwork is to be performed in wet conditions,
the Contractor may reduce soil disturbance by:
• Limiting the size of areas that are stripped of topsoil and left exposed
• Accomplishing earthwork in small sections
• Limiting construction traffic over unprotected soil
• Sloping excavated surfaces to promote runoff
• Limiting the size and type of construction equipment used
• Providing gravel `working mats' over areas of prepared subgrade
• Removing wet surficial soil prior to commencing fill placement each day
• Sealing the exposed ground surface by rolling with a smooth drum compactor or rubber-tired roller at the end of
each working day
• Providing up-gradient perimeter ditches or low earthen berms and using temporary sumps to collect runoff and
prevent water from ponding and damaging exposed subgrades
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Seismic Design Considerations
The Pacific Northwest is seismically active, and the site could be subject to movement from a moderate or major earthquake.
Consequently, moderate levels of seismic shaking should be accounted for during the design life of the project, and the
proposed structure should be designed to resist earthquake loading using appropriate design methodology.
For structures designed using the seismic design provisions of the 2021 International Building Code, the Marysville Sand
underlying the site is classified as Site Class D according to ASCE 7-22. The Structural Engineer should select the
appropriate design response spectrum based on Site Class D soil and the geographical location of the proposed
construction.
Foundation Support
Continuous or isolated spread footings founded on proof-rolled, undisturbed, medium dense native soils or on properly
compacted Structural Fill placed directly over undisturbed native soil can provide foundation support for the proposed
improvements. We recommend that qualified geotechnical personnel confirm that suitable bearing conditions have been
reached prior to placement of Structural Fill or foundation formwork.
To provide proper support, Certerra recommends that existing topsoil, existing fill, and/or loose/soft upper portions of the
native soil be removed from beneath the building foundation area(s) or be replaced with properly compacted Structural Fill
as described in the Fill and Compaction section of this report. Localized overexcavation, if necessary, can be backfilled to
the design footing elevation with lean concrete, or foundations may be extended to bear on undisturbed native soil. In areas
requiring overexcavation to competent native soil, the limits of the overexcavation should extend laterally beyond the edge
of each side of the footing a distance equal to the depth of the excavation below the base of the footing. If lean concrete is
used to backfill the overexcavation, the limits of the overexcavation need only extend a nominal distance beyond the width
of the footing. In addition, Certerra recommends that foundation elements for the proposed structure(s) bear entirely on
similar soil conditions to help prevent differential settlement from occurring. As previously mentioned, Uncontrolled Fill soils
were encountered below the anticipated building footrprint and complete removal may be cost prohibitive.
Continuous and isolated spread footings should be founded 18 inches, minimum, below the lowest adjacent final grade for
freeze/thaw protection.The footings should be sized in accordance with the Structural Engineer's prescribed design criteria
and seismic considerations.
Limited Overexcavation and Replacement
Uncontrolled Fill soils exist on the property.These soils were encountered within our explorations, extending between 3 and
5.25 feet BGS.The depth of this fill, however, could vary across the site. If left in place and not mitigated,the existing fill soils
will increase the risk of post-construction settlements.
In lieu of removing the entirety of the uncontrolled native fill soils below the footprint of the building, Certerra recommends
removal of at least 24 inches of the existing fill below the bottom-of-foundation elevation and floor slab areas.After removal,
the exposed subgrades should be compacted to a firm and unyielding condition with a vibratory Ho-Pac compactor, drum
roller, or similar high-energy compaction equipment. After compacting the exposed soils to a firm and unyielding condition,
improved areas should be backfilled to foundation grades with properly placed and compacted Structural Fill.
Allowable Bearing Capacity
Assuming the above foundation support criteria are satisfied, continuous or isolated spread footings founded directly on firm
and unyielding native soils, on compacted Structural Fill placed directly over firm and unyielding native soils, or on a prism
of Structural Fill overlying remedially densified, firm and unyielding soil may be proportioned using a net allowable soil
bearing pressure of 2,500 pounds per square foot (psf).
The"net allowable bearing pressure" refers to the pressure that can be imposed on the soil at foundation level.This pressure
includes all dead loads, live loads, the weight of the footing, and any backfill placed above the footing. The net allowable
bearing pressure may be increased by one-third for transient wind or seismic loads.
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Foundation Settlement
Settlement of shallow foundations depends on foundation size and bearing pressure, as well as the strength and
compressibility characteristics of the underlying soil. If construction is accomplished as recommended and at the maximum
allowable soil bearing pressure, Certerra estimates the total settlement of building foundations to be less than one inch under
static conditions. Differential settlement between two adjacent load-bearing components supported on competent soil is
estimated to be less than one half the total settlement.
Floor Support
Conventional slab-on-grade floor construction is feasible for the planned site improvements. Floor slabs may be supported
on properly prepared native subgrade, on properly placed and compacted Structural Fill placed over prepared native soil,
or on a prism of 2 feet of Structural Fill overlying suitably firm soil. Prior to placement of the Structural Fill, the underlying
soil should be proof-rolled as recommended in the Site Preparation and Earthwork section of this report.
Certerra recommends that interior concrete slab-on-grade floors be underlain with at least 6 inches of clean, compacted,
free-draining gravel.The gravel should contain less than 3 percent passing the U.S. Standard No. 200 sieve(based on a wet
sieve analysis of that portion passing the U.S. Standard No. 4 sieve). The purpose of this gravel layer is to provide uniform
support for the slab, provide a capillary break, and act as a drainage layer. To help reduce the potential for water vapor
migration through floor slabs, a continuous 10-mil minimum thick polyethylene sheet with tape-sealed joints should be
installed below the slab to serve as an impermeable vapor barrier. The vapor barrier should be installed and sealed in
accordance with the manufacturer's instructions.
The American Concrete Institute (ACI) guidelines suggest that the slab may either be poured directly on the vapor barrier
or on a granular curing layer placed over the vapor barrier depending on construction conditions. Certerra recommends
that the Architect or Structural Engineer specify if a curing layer should be used. If moisture control within the building is
critical, we recommend a representative of Certerra observe the vapor barrier to confirm that joints and penetrations have
been properly sealed. A Subgrade Modulus (k) of 200 pounds per cubic inch (pci) is recommended for use in the design of
concrete slab elements placed on suitably compacted near-surface soils and Structural Fill.
Exterior concrete slabs-on-grade, such as sidewalks, may be supported directly on undisturbed native soil or on properly
placed and compacted Structural Fill; however, long-term performance will be enhanced if exterior slabs are placed on a
layer of clean, durable, well-draining granular material.
Foundation and Site Drainage
Positive surface gradients should be provided adjacent to the proposed building to direct surface water away from the
building and toward suitable drainage facilities. Roof drainage should not be introduced into the perimeter footing drains but
should be separately discharged directly to the stormwater collection system or similar municipality-approved outlet.
Pavement and sidewalk areas, if present, should be sloped and drainage gradients should be maintained to carry surface
water away from the building towards an approved stormwater collection system. Surface water should not be allowed to
pond and soak into the ground surface near buildings or paved areas during or after construction. Construction excavations
should be sloped to drain to sumps where water from seepage, rainfall,and runoff can be collected and pumped to a suitable
discharge facility.
To reduce the potential for groundwater and surface water to seep into interior spaces, Certerra recommends that an exterior
footing drain system be constructed around the perimeter of new building foundations as shown in the Conceptual Footing
and Wall Drain Section (Figure 3)of this report.The drain should consist of a perforated pipe measuring 4 inches in diameter
at minimum, surrounded by at least 12 inches of filtering media. The pipe should be sloped to carry water to an approved
collection system.
The filtering media may consist of open-graded drain rock wrapped in a nonwoven geotextile fabric such as Mirafi 140N (or
equivalent) or wrapped with a graded sand and gravel filter. For foundations supporting retaining walls, drainage backfill
should be carried up the back of the wall and be at least 12 inches wide. The drainage backfill should extend from the
foundation drain to within approximately 1 foot of the finished grade and consist of open-graded drain rock containing less
than 3 percent fines by weight passing the U.S.Standard No.200 sieve(based on a wet sieve analysis of that portion passing
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the U.S. Standard No. 4 sieve). The invert of the footing drainpipe should be placed at approximately the same elevation as
the bottom of the footing or 12 inches below the adjacent floor slab grade, whichever is deeper, so that water will be
contained.This process prevents water from seeping through walls or floor slabs. The drain system should include cleanouts
to allow for periodic maintenance and inspection.
Please understand that the above recommendations are intended to assist the Design engineer and/or Architect in
development of foundation and site drainage parameters and are based on our experience with similar projects in the area.
The final foundation and site drainage plan that will be incorporated into the project plans is to be determined by the design
team.
Resistance to Lateral Loads
The lateral earth pressures that develop against retaining walls will depend on the method of backfill placement, degree of
compaction, slope of backfill, type of backfill material, provisions for drainage, magnitude and location of any adjacent
surcharge loads,and the degree to which the wall can yield laterally during or after placement of backfill. If the wall is allowed
to rotate or yield so the top of the wall moves an amount equal to or greater than about 0.001 to 0.002 times its height (a
yielding wall), the soil pressure exerted comprises the active soil pressure. When a wall is restrained against lateral
movement or tilting (a nonyielding wall), the soil pressure exerted comprises the at rest soil pressure. Wall restraint may
develop if a rigid structural network is constructed prior to backfilling or if the wall is inherently stiff.
Certerra recommends that yielding walls under drained conditions be designed for an equivalent fluid density of 35 pounds
per cubic ft (pcf), for Structural Fill and native soils in active soil conditions. Nonyielding walls under drained conditions
should be designed for an equivalent fluid density of 55 pcf, for Structural Fill and native soils in at-rest conditions. The
design of walls should include appropriate lateral pressures caused by surcharge loads located within a horizontal distance
equal to or less than the height of the wall. For uniform surcharge pressures, a uniformly distributed lateral pressure equal
to 35 percent and 50 percent of the vertical surcharge pressure should be added to the lateral soil pressures for yielding
and nonyielding walls, respectively. Certerra also recommends that a seismic surcharge of 8*H psf be included where H is
the wall height. The seismic surcharge should be modeled as a rectangular distribution with the resultant applied at the
midpoint of the wall.
Passive earth pressures developed against the sides of building foundations, in conjunction with friction developed between
the base of the footings and the supporting subgrade,will resist lateral loads transmitted from the structure to its foundation.
For design purposes,the passive resistance of well-compacted fill placed against the sides of foundations is equivalent to a
fluid with a density of 250 pcf. The recommended value includes a safety factor of about 1.5 and is based on the assumption
that the ground surface adjacent to the structure is level in the direction of movement for a distance equal to or greater than
twice the embedment depth. The recommended value also assumes drained conditions that will prevent the buildup of
hydrostatic pressure in the compacted fill. Retaining walls should include a drain system constructed in general accordance
with the recommendations presented in the Foundation and Site Drainage section of this report. In design computations,
the upper 12 inches of passive resistance should be neglected if the soil is not covered by floor slabs or pavement. If future
plans call for the removal of the soil providing resistance,the passive resistance should not be considered.
An allowable coefficient of base friction of 0.35, applied to vertical dead loads only, may be used between the underlying
imported granular Structural Fill and the base of the footing. If passive and frictional resistance are considered together, one
half the recommended passive soil resistance value should be used since larger strains are required to mobilize the passive
soil resistance as compared to frictional resistance. A safety factor of about 1.5 is included in the base friction design value.
Certerra does not recommend increasing the coefficient of friction to resist seismic or wind loads.
Temporary and Permanent Slopes
The Contractor is responsible for construction slope configurations and maintaining safe working conditions, including
temporary excavation stability. All applicable local, state, and federal safety codes should be followed. All open cuts should
be monitored during and after excavation for any evidence of instability. If instability is detected,the Contractor should flatten
the side slopes or install temporary shoring.
Temporary excavations in excess of 4 feet should be shored or sloped in accordance with Safety Standards for Construction
Work Part N, WAC 296-155-66403. Temporary unsupported excavations in the Uncontrolled Fill and Marysville Sand soils
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encountered at the project site are classified as a Type C soil according to WAC 296-155-66401 and may be sloped as steep
as 1.5:1 (Horizontal: Vertical). All soils encountered are classified as Type C soil in the presence of groundwater seepage.
Flatter slopes or temporary shoring may be required in areas where groundwater flow is present and unstable conditions
develop.
Temporary slopes and excavations should be protected as soon as possible using appropriate methods to prevent erosion
from occurring during periods of wet weather.
Certerra recommends that permanent cut or fill slopes be designed for inclinations of 2H:1V or flatter. Permanent cuts or
fills used in detention ponds, retention ponds,or earth slopes intended to hold water should be 3H:1 V or flatter.All permanent
slopes should be vegetated or otherwise protected to limit the potential for erosion as soon as practical after construction.
Utilities
Utility trenches must be properly backfilled and compacted to reduce cracking or localized loss of foundation, slab, or
pavement support. Excavations for new shallow underground utilities are expected to be placed within Uncontrolled Fill or
native soils.
Trench backfill in improved areas(beneath structures, pavements,sidewalks,etc.)should consist of Structural Fill as defined
in the Fill and Compaction section of this report. Outside of improved areas, trench backfill may consist of reused material
provided the backfill can be compacted to the project specifications. Trench backfill should be placed and compacted in
general accordance with the recommendations presented in the Fill and Compaction section of this report.
Surcharge loads on trench support systems due to construction equipment, stockpiled material, and vehicle traffic should
be included in the design of any anticipated shoring system. The Contractor should implement measures to prevent surface
water runoff from entering trenches and excavations. In addition, vibration as a result of construction activity and traffic may
cause caving of the trench walls.
The Contractor is responsible for trench configurations. All applicable local, state, and federal safety codes should be
followed. All open cuts should be monitored by the Contractor during excavation for any evidence of instability. If instability
is detected, the Contractor should flatten the side slopes or install temporary shoring. If groundwater or groundwater
seepage is present, and the trench is not properly dewatered, the soil within the trench zone may be prone to caving,
channelling, and running. Trench widths may be substantially wider than under dewatered conditions.
Pavement Subgrade Preparation
Selection of a pavement section is typically a choice relative to a higher initial cost and lower long-term maintenance, or a
lower initial cost with more frequent maintenance. For this reason, we recommend that the Owner participates in the
selection of the proposed pavement sections planned for the site. Site grading plans should include provisions for sloping
of the subgrade soils in proposed pavement areas, so that passive drainage of the pavement section(s) can proceed
uninterrupted during the life of the project. The proposed pavement areas should be prepared as indicated in the Site
Preparation and Earthwork section of this report. If existing fill is exposed after initial site stripping and it cannot be remedially
compacted to the requirements for Structural Fill, limited overexcavation and replacement with Structural Fill should occur.
We provide further detail for removal depths of unsuitable soil and subgrade preparation recommendations in the Foundation
Support and Slab on Grade support sections of this report.
Light-Duty Flexible Pavement
Certerra anticipates that asphalt pavement will be used for new passenger vehicle access drives and parking areas. We
recommend that a standard, or`light duty,' pavement section consist of 2.5 inches of /z-inch HMA asphalt above 6 inches of
crushed surfacing base course (CSBC) meeting criteria set forth in the Washington State Department of Transportation
(WSDOT) Standard Specification 9-03.9[3] Crushed Surfacing Base Course.
Certerra is available to further consult, review, and/or modify our pavement section recommendations based on further
discussion and/or analysis with the project team/owner.The above pavement sections are initial recommendations and may
be accepted and/or modified by the site Civil Engineer based on the actual finished site grading elevations and/or the owner's
preferences.
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Heavy-Duty Flexible Pavement
The drive-thru lane and/or areas that will be accessed by more heavily loaded vehicles,emergency access vehicles,garbage
trucks, and similar vehicles will require a thicker asphalt section and should be designed using a paving section consisting
of 3 inches of Class 1/2-inch HMA asphalt surfacing above 6 inches of CSBC meeting criteria set forth in WSDOT Standard
Specification 9-03.9[3].
Concrete Pavement
Concrete pavements could be used for access and drive areas. Design of concrete pavements is a function of concrete
strength, reinforcement steel, and the anticipated loading conditions for the roads. For design purposes, a vertical modulus
of subgrade reaction of 200 pounds per cubic inch(pci)should be expected for concrete roadways constructed over properly
placed and compacted Structural Fill. Certerra expects that concrete pavement sections, if utilized, will be at least 6 inches
thick and be founded on a minimum of 6 inches of compacted CSBC. The design of concrete pavements will need to be
performed by a Structural Engineer. Certerra recommends that subgrade soils supporting concrete pavement sections
include minor grade changes to allow for passive drainage away from the pavement.
Certerra is available to further consult, review, and/or modify our pavement section recommendations based on further
discussion and/or analysis with the project team/Owner.The above pavement sections are initial recommendations and may
be accepted and/or modified by the site Civil Engineer based on the actual finished site grading elevations and/or the
Owner's preferences.
Stormwater Infiltration Potential
Based on the presence of predominantly granular materials at depth, it is our opinion that the on-site infiltration of stormwater
is feasible for this project site. Please note that there are thin silt interbeds that exist between 4 and 8 feet below existing site
grades. These silt interbeds are expected to have negative effects on infiltration. As such, Certerra recommends that the
bottom of facilities be extended through existing fill soils and silt interbeds, and be founded in the granular Marysville Sand
that exists at depths of about 8 feet below existing site grades. If desired, shallower facilities may be constructed as long as
excavated "slot trenches" are extended from the bottom of the facility and through the silt lenses that exist between 4 and
8 feet below existing site grades. Slot trenches, if utilized, should be backfilled with C33 Sand, or similar high-permeability,
predominately granular materials that will hydraulically connect the infiltration facility to the receptor soils at depth.
Provided that infiltration facilities are extended to predominantly granular soil at approximately 8 feet below existing site
grades, a preliminary, corrected infiltration rate of 0.5 inches per hour may be assumed for the design of these facilities.
Please note that this rate is representative of siltier soils in the unit with a correction factor. Laboratory analysis of collected
soil samples indicates some areas with clean sands and gravels are expected to have infiltration rates greater than 0.5 inches
per hour. The location and depths of proposed infiltration facilities are currently unknown. As such, designing a facility to a
higher infiltration rate at an unknown location and with an unknown facility depth presents moderate amounts of risk to the
Owner. If desired, a field performance test (Pilot Infiltration Testing) can be performed for an additional fee and upon the
completion of Civil Design services. It will be logistically challenging to perform a Pilot Infiltration Test at approximately 8 feet
below existing site grades, but such a test can be performed if it becomes necessary and if a faster infiltration rate is needed
for the design.
At the time of this report, a specific infiltration facility design is not available. As such, it should be expected that multiple
iterations may be needed to initially size facilities and then determine the necessity of reductions to the presented infiltration
rate to account for groundwater mounding.
Stormwater Treatment
The stormwater facilities on-site may require some form of pollutant pretreatment with an amended soil prior to on-site
infiltration or offsite discharge. The reuse of on-site topsoil is often the most sustainable and cost-effective method for
pollutant treatment purposes. Cation exchange capacities,organic contents,and pH of site subsurface soils were also tested
to determine possible pollutant treatment suitability.
Cation exchange capacity, organic content, and pH tests were performed by Northwest Agricultural Consultants on three
soil samples collected from the project site. A summary of the laboratory test results is presented in Table 2 below.
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Cation Exchange Capacity, TABLE 2
Organic
Test Pit C
Depth apacity Content pH
ID (ft) J=LqJJ
iigrams)
TP-1 0.25 Topsoil 16.9 6.69 5.8
TP-2 0.25 Topsoil 28.9 12.04 5.5
TP-3 5.0 Marysville Sand 16.3 3.48 6.2
Suitability for onsite pollutant treatment is determined in accordance with SSC-6 of the Manual. Soils with an organic content
of greater than or equal to 1 percent and a cation exchange capacity of greater than or equal to 5 meq/100 grams are
characterized as suitable for stormwater treatment. Based on the results shown in Table 2, topsoil is suitable for stormwater
treatment. However, reduced rates of infiltration should be anticipated in the Marysville Sand soils due to these soils'elevated
silt contents.
On-site soils can be amended by mixing higher silt content soils or adding mulch (or other admixtures)to elevate the cation
exchange capacity and organic contents. On-site amended soil requires additional testing to confirm compliance with
ecological regulations. Certerra is available to perform additional laboratory testing as part of an expanded scope of services
if the soil is to be amended. Alternatively, the owner may elect to import amended soils with the desired properties for
planned treatment facilities.
Geotechnical Consultation and Construction Monitoring
Certerra recommends that we be involved in the project design review process. The purpose of the review is to verify that
the recommendations presented in this report are understood and incorporated in the design and specifications.
We also recommend that geotechnical construction monitoring services be provided. These services should include
observation by Certerra personnel during Structural Fill placement, compaction activities and subgrade preparation
operations to confirm that design subgrade conditions are obtained beneath the areas of improvement.
Periodic field density testing should be performed to verify that the appropriate degree of compaction is obtained. The
purpose of these services is to observe compliance with the design concepts, specifications, and recommendations of this
report. In the event that subsurface conditions differ from those anticipated before the start of construction, Certerra
Services would be pleased to provide revised recommendations appropriate to the conditions revealed during construction.
Certerra is available to provide a full range of materials testing and special inspection during construction as required by the
local building department and the International Building Code. This may include specific construction inspections on
materials such as reinforced concrete, reinforced masonry,wood framing and structural steel. These services are supported
by our fully accredited materials testing laboratory.
Use of This Report
Certerra Services has prepared this report for the exclusive use of Pacific Bells, LLC and their design consultants for specific
application to the design of the proposed development located on Parcel No. 00847300000200 in Arlington, Washington.
Use of this report by others is at the user's sole risk. This report is not applicable to other site locations. Our services are
conducted in accordance with accepted practices of the geotechnical engineering profession; no other warranty, express
or implied, is made as to the professional advice included in this report.
Our site explorations indicate subsurface conditions at the dates and locations indicated. It is not warranted that these
conditions are representative of conditions at other locations and times. The analyses, conclusions, and recommendations
contained in this report are based on site conditions to the limited depth and time of our explorations, a geological
reconnaissance of the area,and a review of previously published geological information for the site. If variations in subsurface
conditions are encountered during construction that differ from those contained within this report, Certerra should be
allowed to review the recommendations and, if necessary, make revisions. If there is a substantial lapse of time between
certerra.com 20527 67"Avenue NE,Arlington,WA 98223 13
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submission of this report and the start of construction, or if conditions change due to construction operations at or adjacent
to the project site, we recommend that we review this report to determine the applicability of the conclusions and
recommendations contained herein.
The earthwork Contractor is responsible to perform all work in conformance with all applicable WISHA/OSHA regulations.
Certerra Services, Inc. is not responsible for job site safety on this project, and this responsibility is specifically disclaimed.
Attachments: Figure 1 Vicinity Map
Figure 2 Site and Exploration Plan
Figure 3 Typical Footing and Wall Drain Section
Figure 4 Soil Classification System and Key
Figure 5—7 Test Pit Exploration Logs
Figure 8—9 Grain Size Test Data
Attachment NW Agricultural Consultants Test Results
Attachment Report Limitations and Guidelines for its Use (4 Pages)
References
American Society of Civil Engineers,(2017). Minimum design loads and associated criteria for buildings and other structures:
ASCE/SEI 7-16. Reston,Virginia: American Society of Civil Engineers.
American Society for Testing and Materials (ASTM). Standard Practice for Classification of Soils for Engineering Purposes
(Unified Soil Classification System). ASTM D2487— 17el.
American Society for Testing and Materials (ASTM). Standard Practice for Description and Identification of Soils (Visual-
Manual Procedures).ASTM D2488— 17el.
American Society for Testing and Materials(ASTM). (2017).ASTM D6938, Standard Methods for In-Place Density and Water
Content of Soil and Soil-Aggregate by Nuclear Methods.
American Society for Testing and Materials (ASTM). Standard Test Methods for Laboratory Compaction Characteristics of
Soil Using Modified Effort. ASTM D1557— 12el.
Arlington (WA) Municipal Code—Chapter 20.93 Part V(Geologically Hazardous Areas), June 4, 2025. Retrieved September
2025.
Atwater, B.F., and Haley, E. H., (1997) Recurrence Intervals for Great Earthquakes of the Past 3,500 Years at Northeastern
Willapa Bay, Washington. USGS Survey Professional Paper 1576.
Gariepy, D., Graul, C. Heye, A., Howie, D., Labib, F. & Song, K. (n.d.) 2019. Stormwater Management Manual for Western
Washington (2019 SMMWW) (pp. 1-1108) (United States, Washington Department of Ecology).
International Building Code (IBC), 2021. International Code Council.
Snohomish County Planning and Development Services. PDS Map Portal. (n.d.) Retrieved from
https://gismaps.snoco.org/Htm15Viewer/index.htmI?viewer=pdsmapportal in September 2025.
Minard. J.P., 1985, Geologic map of the Arlington West 7.5-minute quadrangle, Snohomish County, Washington: U.S.
Geological Survey MF-1740, scale 1:24,000.
USDA Web Soil Survey. (August 31, 2021). Retrieved September 2025, from
https.Ilwebsoilsurvey.sc.egov.usda.govIAppIWebSoilSurvey aspx.
certerra.com 20527 67"Avenue NE,Arlington,WA 98223 14
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Washington Administrative Code (WAC). (2020). WAC 296-155-6640, Retrieved September 2025, from
https://app.leg.wa.gov/wac/default.aspx?cite=296-155-66403.
Washington State Department of Natural Resources - Online Web Services. Washington Geologic Information Portal.
Retrieved in September 2025.
certerra.com 20527 6711 Avenue NE,Arlington,WA 98223 15
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Date: 9-15-2025 By: JV Scale: As Shown Project
VICINITY MAP 25-2170
CERTERRAARLINGTON TACO BELL Figure
GEOTEST PARCEL No.00847300000200
ARLINGTON,WASHINGTON
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Date:9-15-2025 By: JV Scale: As Shown Project
SITE AND EXPLORATION PLAN 25-2170
CERTERRA ARLINGTON TACO BELL Figure
GEOTEST PARCEL No.00847300000200
ARLINGTON,WASHINGTON
CONCEPTUAL FOOTINGS WITH INTERIOR SLAB-ON-GRADE
' ' < Typical Framing
Compacted Low-Permeability Soil
(12 inch minimum)
Floor Slab
or Pavement •,•,',' , , , , , , , , , , , , , , , ,
(2 inch minimum)
. . . . . . . . . . . . . . . . . . .
, , , , , , , , , , , , , , , , ,
Slope to drain away
Vapor Barrier
from structure.
•.f:f:f:f:f:f:;:f:;:f:f:f:f. . f f.;: .;.
_ — — ',',',' ti'ti•ti•ti•ti•ti•ti•ti•ti•ti•ti•ti•ti•ti•ti ti•ti•ti•ti•ti•ti•ti•ti•ti•ti•ti•ti•ti•ti•
— r•r•r•r•r•r•1•r•r•r•r•r•r•r• 1•r•r•r•r•r•r•r•r•1•r•r•r•r•1
•+•+•�• ti.ti.ti.ti.ti.ti.ti.ti.ti.ti.ti.ti.ti.ti.ti. .ti.ti.ti.ti.ti.ti.ti.ti.ti.ti.ti.ti•tilti.l
Gravel Capillary Break
minimum,typically clear crushed)
Suitable Soil
/ +,+,+• .
•,•,• •. •. Free Draining Sand
+ +' and Gravel Fill
Approved Non-woven
Geotextile Filter Fabric + + + + + + + +
(18 inch minimum fabric lap) ' ' '
Suitable Soil
Drainage Material
(Drain Rock or Clear
Crushed Rock w/no fines) Appropriate Waterproofing
Applied to Exterior of Wall
Four Inch Diameter,Perforated,Rigid PVC Pipe
(Perforations oriented down directed to suitable discharge)
Notes:
Footings should be properly buried for frost protection in accordance with International Building
Code or local building codes (Typically 18 inches below exterior finished grades).
This figure is not intended to be representative of a design. This figure is intended to present
concepts that can be incorporated into a functional foundation drain designed by a Civil Engineer. In
all cases, refer to the Civil plan sheet for drain details and elevations.
This footing drain detail may need to be modified from this conceptual drawing to fit the dimensions
of the planned footing and slab configuration.
Date:9-15-2025 By: JV Scale: None Project
CONCEPTUAL FOOTING & WALL DRAIN SECTION 25-2170
CERTERRA ARLINGTON TACO BELL
1 GEOTEST PARCEL No.00847300000200 Figure
ARLINGTON,WASHINGTON 3
Soil Classification System
Uscs
MAJOR GRAPHIC LETTER TYPICAL
DIVISIONS SYMBOL SYMBOL DESCRIPTIONS(')(2)
GRAVEL AND CLEAN GRAVEL o o o°o;o GW Well-graded gravel;gravel/sand mixture(s);little or no fines
GRAVELLY SOIL (Little or no fines) o,6 o�?o GP Poorly graded gravel;gravel/sand mixture(s);little or no fines
O 'N ° ° .
m y
.a (More than 50%of
coarse fraction retained GRAVEL WITH FINES GM Silty gravel;gravel/sand/silt mixture(s)
M a)W E o on No.4 sieve) (Appreciable amount of
z o N fines) GC Clayey gravel;gravel/sand/clay mixture(s)
o
w SAND AND CLEAN SAND SW Well-graded sand;gravelly sand;little or no fines
CO c;t SANDY SOIL (Little or no fines)
QSP Poorly graded sand;gravelly sand;little or no fines
O 2 (More than 50%of
U_ m coarse fraction passed SAND WITH FINES SM Silty sand;sand/siltmixture(s)
through No.4 sieve) (Appreciable amount of
fines) SC Clayey sand;sand/clay mixture(s)
Inorganic silt and very fine sand;rock flour;silty or clayey fine
f6 ��', SILT AND CLAY ML sand or clayey silt with slight plasticity
.N Inorganic clay of low to medium plasticity;gravelly clay;sandy
0 E N (Liquid limit less than 50) C�' clay;silty clay;lean clay
W ° o
z o z QL Organic silt;organic,silty clay of low plasticity
O C N
� 0ca0
C�7 r� SILT AND CLAY MH Inorganic silt;micaceous or diatomaceous fine sand
CH Inorganic clay of high plasticity;fat clay
LL 5 E (Liquid limit greater than 50)
OH Organic clay of medium to high plasticity;organic silt
HIGHLY ORGANIC SOIL PT Peat;humus;swamp soil with high organic content
GRAPHIC LETTER
OTHER MATERIALS SYMBOL SYMBOL TYPICAL DESCRIPTIONS
PAVEMENT AC Or PC Asphalt concrete pavement or Portland cement pavement
ROCK RK Rock(See Rock Classification)
WOOD WD Wood,lumber,wood chips
DEBRIS O O O Dg I Construction debris,garbage
Notes: 1. Soil descriptions are based on the general approach presented in the Standard Practice for Description and Identification of Soils(Visual-Manual Procedure),
as outlined in ASTM D 2488.Where laboratory index testing has been conducted,soil classifications are based on the Standard Test Method for Classification
of Soils for Engineering Purposes,as outlined in ASTM D 2487.
2. Soil description terminology is based on visual estimates(in the absence of laboratory test data)of the percentages of each soil type and is defined as follows:
Primary Constituent: >50%-"GRAVEL,""SAND,""SILT,""CLAY,"etc.
Secondary Constituents: >30%and<50%-"very gravelly,""very sandy,""very silty,"etc.
>12%and<30%-"gravelly,""sandy,""silty,"etc.
Additional Constituents: > 5%and<12%-"slightly gravelly,""slightly sandy,""slightly silty,"etc.
< 5%-"trace gravel,""trace sand,""trace silt,"etc.,or not noted.
Drilling and Sampling Key Field and Lab Test Data
SAMPLE NUMBER&INTERVAL SAMPLER TYPE
Code Description Code Description
Sample Identification Number a 3.25-inch O.D.,2.42-inch I.D.Split Spoon PP=1.0 Pocket Penetrometer,tsf
b 2.00-inch O.D.,1.50-inch I.D.Split Spoon TV=0.5 Torvane,tsf
Recovery Depth Interval c Shelby Tube PID=100 Photoionization Detector VOC screening,ppm
1� 14-- Sample Depth Interval d Grab Sample W=10 Moisture Content,%
J e Other-See text if applicable D=120 Dry Density,pcf
Portion of Sample Retained 1 300-lb Hammer,30-inch Drop -200=60 Material smaller than No.200 sieve,%
for Archive or Analysis 2 140-lb Hammer,30-inch Drop GS Grain Size-See separate figure for data
3 Pushed AL Atterberg Limits-See separate figure for data
4 Other-See text if applicable GT Other Geotechnical Testing
Groundwater CA Chemical Analysis
L7 Approximate water elevation at time of drilling(ATD)or on date noted. Groundwater
ATD levels can fluctuate due to precipitation,seasonal conditions,and other factors.
Arlington Taco Bell Figure
rEOTEST /1
CERTERRA Parcel No. 00847300000200 Soil Classification System and Key
Arlington, Washington u1 A
f G
TP-1
SAMPLE DATA SOIL PROFILE GROUNDWATER
o
E— I.a E 0 Excavation Method. Tracked Excavator
T
Z `� _ N Ground Elevation(ft). -134
t a� v v o t
E.
c E i N Excavated By: E&D Excavating,Inc./JV
0 = d SMJ \ Loose,brown,dry,gravelly,very silty SAND —
with numerous organics(Topsoil) ____ /
SM \ org— � p � —J Groundwater not encountered.
2 Medium dense,brown,dry,silty SAND with
occasional organics,orange mottling
= d (Uncontrolled Fill) —
SM Certerra observed an increase in silt content /
4 = d \below2.5feet.-------------/
--- —
Medium dense,dark brown,damp,very
silty SAND(Weathered Marysville Sand)
6 SM Mm dense to Te nse,brown,damp,silty,
= d ediu very gravelly SAND with orange mottling,
trace cobbles(Weathered Marysville Sand) —J-
8 = d SW Medium dense to dense,orange brown,
moist,very gravelly SAND with orange
10 d W=5
mottling(Marysville Sand)
GS
Excavation terminated at planned depth.
Test Pit Completed 09/10/25
Total Depth of Test Pit=10.0 ft.
12
TP-2
SAMPLE DATA SOIL PROFILE GROUNDWATER
o
E a -6 Excavation Method. Tracked Excavator
_ 7- �,
Y N
aj `� Ground Elevation(ft). —135
t v v o
a) EN Excavated By: E&D Excavating, Inc./JV
0 = d SMJ Loose,brown,dry,gravelly,very silty SAND —
SM \with numerous organics(Topsoil) /
------ — — -----j Groundwater not encountered.
2 Medium dense,brown,dry,slightly gravelly,very
silty SAND with numerous organics
= d o:o GP (Uncontrolled Fill) —______ _
--�
o O Dense,brown,moist,sandy GRAVEL with
4 60 trace cobbles(Uncontrolled Fill)
0 0.
= d W=28 — — -- — — -- —————
SM Loose to medium dense,dark brown to
6 = d W S 7 SW black,slightly gravelly,silty SAND(Weathered /
GS _ \Marysville Sand)
= d ML \ Dense,brown,moist,very gravelly SAND /
8 with trace cobbles(Marysville Sand) /
Loose to stiff,blue-gray,moist,sandy SILT
SM \`(Silty Interbed within Marysville Sand)--
10 d Medium dense,blue-gray-brown,damp,
Test Pit Completed 09/10/25 gravelly,very silty SAND(Marysville Sand)
Total Depth of Test Pit=10.0 ft. Excavation terminated at planned depth.
12
Notes: 1.Stratigraphic contacts are based on field interpretations and are approximate.
2.Reference to the text of this report is necessary for a proper understanding of subsurface conditions.
3.Refer to"Soil Classification System and Key"figure for explanation of graphics and symbols.
4.Approximate elevations obtained from Carropo interactive web portal.
Arlington Taco Bell Figure
i EOTEST CERTERRA Parcel No. 00847300000200 Log of Test Pits
1 G
Arlington, Washington
TP-3
SAMPLE DATA SOIL PROFILE GROUNDWATER
o
E— a E 0 Excavation Method. Tracked Excavator
T
j `� N Ground Elevation(ft). —135
s a� v v 0 t
v c E i N Excavated By: E&D Excavating,Inc./JV
0 = d SMJ \ Loose,brown,dry,gravelly,very silty SAND —
= d SM \with numerous organics(Topsoil)
2 Medium dense,dark brown,dry to damp,
slightly gravelly,very silty SAND with
= d occasional organics(Uncontrolled Fill)
4
ML Stiff,dark brown,damp,very sandy SILT
= d SM with orange mottling(Weathered Marysville Sand)
= d W=22 Stiff,brown to gray-brown,damp,very silty
GS SAND with orange mottling(Marysville Sand)
8
s d 0,6. GP Medium dense to dense,brown,very sandy
o. GRAVEL with orange mottling,minor silt
10 °o seams(Marysville Sand)
°o Slight groundwater seepage encountered at
W=11 0.0. Certerra observed an increase in moisture 11.0 ft.
12 d GS content,increase in silt content,and the
color transition to blue gray below 11 feet.
Test Pit Completed 09/10/25 Excavation terminated at planned depth.
14 Total Depth of Test Pit=12.0 ft.
TPA
SAMPLE DATA SOIL PROFILE GROUNDWATER
o
E a o Excavation Method. Tracked Excavator
Y N
aj v Ground Elevation(ft). —134
v O t
v N Excavated By: E&D Excavating, Inc./JV
o cn 06 V) F C7 �
0 = d SM Loose,brown,dry,gravelly,very silty SAND
SM th numerous organics(Topsoil)____—_—
2 = d SM Loose,light brown,dry,silty,very gravelly
SAND with occasional organics /^
= d (Uncontrolled Fill) -----------/
4 Medium dense,dark brown,dry to damp,
slighty gravelly,very silty SAND with
= d ML \`occasional organics(Uncontrolled Fill)----/^
6 ML \ Stiff,brown to dark brown,damp,slightly
\ sandy SILT with orange mottling(Weathered /
= d W=30 \ Marysville Sand) /
8 GS T 7'077 PP=1.5 tsf /
= d
°'o \Medium stiff to stiff,blue-gray,damp,sandy /
10 R SILT(Silty Interbed within Marysville Sand) /
= d o°. ------------------
o.O. Medium dense,orange-brown,damp to � Slight groundwater seepage encountered at
12 0 0 moist,slightly silty,sandy GRAVEL with - 11.5 ft.
orange mottling(Marysville Sand)
Test Pit Completed 09/10/25 Excavation terminated at planned depth.
14 Total Depth of Test Pit=12.0 ft.
Notes: 1.Stratigraphic contacts are based on field interpretations and are approximate.
2.Reference to the text of this report is necessary for a proper understanding of subsurface conditions.
3.Refer to"Soil Classification System and Key"figure for explanation of graphics and symbols.
4.Approximate elevations obtained from Carropo interactive web portal.
Arlington Taco Bell Figure
i CERTERRA GEOTEST Parcel No. 00847300000200 Log of Test Pits
1
Arlington, Washington
TP-5
SAMPLE DATA SOIL PROFILE GROUNDWATER
o
E— a E 0 Excavation Method. Tracked Excavator
T
Z 76 _ N
aj Ground Elevation(ft). -133
t v v o t
v c E i N Excavated By: E&D Excavating,Inc./JV
in Ln co
0 = d SM Loose,brown,dry,gravelly,very silty SAND
= d SM _withnummerousorganics(T_opsoil)__----j—
2 = d Loose,light brown,dry,silty,gravelly SAND
with occasional organics(Uncontrolled Fill)
= d Certerra observed an increase in silt content
4 below 2 feet.
= d W=22 ML Certerra observed orange mottling below 3
GS \feet.----------------J
6 Medium stiff to stiff,dark brown,damp,
sandy SILT with orange mottling(Weathered
= d W=6 0. GP Masville Sand
8 GS °.°. �—ry ry— )------------�
Medium dense,dark brown,damp,very
= d D°° sandy GRAVEL with orange mottling
10 D06 (Marysville Sand)
3.0
°o slight groundwater seepage encountered at
12 = d °o = 11.8 ft.
Excavation terminated at planned depth.
Test Pit Completed 09/10/25
14 Total Depth of Test Pit=12.0 ft.
Notes: 1.Stratigraphic contacts are based on field interpretations and are approximate.
2.Reference to the text of this report is necessary for a proper understanding of subsurface conditions.
3.Refer to"Soil Classification System and Key"figure for explanation of graphics and symbols.
4.Approximate elevations obtained from Carropo interactive web portal.
Arlington Taco Bell Figure
1 CERTERRA GEOTEST I
Parcel No. 00847300000200 Log of Test Pits 7
1
Arlington, Washington
U.S.SIEVE OPENING IN INCHES I U.S.SIEVE NUMBERS I HYDROMETER
6 4 3 2 1.5 1 1/23/8 3 6 810 1416 20 30 40 50 60 100 140 200
100
90
80
70
60
T
Q
50
ii
c
U
a 40
30
20
10
0
100 10 1 0.1 0.01 0.001
Grain Size in Millimeters
Cobbles Gravel Sand Silt or Clay
coarse fine coarse medium fine
Point Depth Classification ILL PL PI C,� Cu
• TP-1 10.0 Very gravelly SAND (SW) 1.05 10.67
m TP-2 5.3 Slightly gravelly,silty SAND (SM)
A TP-2 6.0 Very gravelly SAND (SW) 1.91 27.00
* TP-3 6.5 Very silty SAND (SM)
O TP-3 12.0 Very sandy GRAVEL (GP) 0.94 16.55
Point Depth D D D D D %Coarse %Fine %Coarse %Medium %Fine %Fines
p 90 60 50 30 10 Gravel Gravel Sand Sand Sand
0 TP-1 10.0 17.66 6.472 4.478 2.033 0.607 7.7 40.8 21.9 23.5 4.0 2.1
m TP-2 5.3 3.909 0.383 0.254 0.091 0.0 8.2 7.9 21.3 35.3 27.3
A TP-2 6.0 14.724 6.055 4.162 1.612 0.224 0.0 46.9 20.3 16.3 12.1 4.4
* TP-3 6.5 0.906 0.249 0.095 0.0 0.0 1.3 26.7 24.0 48.0
O TP-3 12.0 18.736 6.951 4.781 1.653 0.42 9.6 40.6 17.0 22.7 8.1 2.0
C,; = D3o2/(D60* D1o) To be well graded: 1 < C,< 3 and
CG = D6o/D10 C, > 4 for GW or C, > 6 for SW
Arlington Taco Bell Figure
1 .TE.T RA Parcel No. 00847300000200 Grain Size Test Data f GEOTEST 4
Arlington, Washington 8
U.S.SIEVE OPENING IN INCHES I U.S.SIEVE NUMBERS I HYDROMETER
6 4 3 2 1.5 1 34 1/23/8 3 6 810 1416 20 30 40 50 60 100 140 200
100
90
80
70
60
T
Q
ii50
c
U
a 40
30
20
10
0
Itit: --
100 10 1 0.1 0.01 0.001
Grain Size in Millimeters
Cobbles Gravel Sand Silt or Clay
coarse fine coarse medium fine
Point Depth Classification ILL PL PI Cc C,
• TP-4 7.5 Sandy SILT (ML)
m TP-5 5.0 Very sandy SILT (ML)
A TP-5 7.5 Very sandy GRAVEL (GP) 0.80 27.00
Point Depth D D D D D %Coarse %Fine %Coarse %Medium %Fine %Fines
p 90 60 50 30 io Gravel Gravel Sand Sand Sand
• TP-4 7.5 0.0 0.0 0.7 2.1 3.9 93.3
m TP-5 5.0 0.561 0.111 0.0 0.0 0.8 13.2 31.0 55.0
A TP-5 7.5 15.336 6.889 4.447 1.188 0.255 0.0 48.8 15.1 18.8 13.8 3.4
C, = D3o2/(D60" D1o) To be well graded: 1 < C,< 3 and
CG = D6o/D10 C, > 4 for GW or C, > 6 for SW
Arlington Taco Bell Figure
1 CERTERRA Parcel No. 00847300000200 Grain Size Test Data ^
1 G EOTEST
Arlington, Washington
Northwest Agricultural
Consultants
24SA9936
Report: 74327-1 509.7817450 www^wagc^m lab@nwag.mm GEOTEST SERVICES INC
Date: 2025-09-11 741 MARINE DR
Project Name: Arlington Taco Bell BELLINGHAM,WA 98225
Project Number: 10-252170-0
Sample Sulfate pH Resistivity OM CEC Chloride Moisture Sand Silt Clay Class
ID ma/kci S.U. ohm-m % me /100 mg/kg % % % %
TP-1 @ 0.25' 5.8 6.69 16.9
TP-3 @ 0.25' 5.5 12.04 28.9
TP-3 @ 5.0' 6.2 3.48 16.3
Analyte Sulfate pH Resistivity OM CEC Chloride Moisture Sand Silt Clay Class
Method SM-4500 SO4 E SM 4500-H+B SM 2510 B ASTM D2974 EPA 9081 ASTM D512 Gravimetric Hydrometer Hydrometer Hydrometer Hydrometer
1 CERTERRA
1 GEOTEST
REPORT LIMITATIONS AND GUIDELINES FOR ITS USE '
Subsurface issues may cause construction delays, cost overruns, claims, and disputes. While you cannot eliminate all such
risks, you can manage them. The following information is provided to help:
Geotechnical Services are Performed for Specific Purposes, Persons, and Projects
At Certerra our geotechnical engineers and geologists structure their services to meet specific needs of our clients. A
geotechnical engineering study conducted for a civil engineer may not fulfill the needs of an owner,a construction contractor
or even another civil engineer. Because each geotechnical engineering study is unique, each geotechnical engineering
report is unique, prepared solely for the client. No one except you should rely on your geotechnical engineer who prepared
it.And no one—not even you—should apply the report for any purpose or project except the one originally contemplated.
Read the Full Report
Serious problems have occurred because those relying on a geotechnical engineering report did not read it all. Do not rely
on an executive summary. Do not read selected elements only.
A Geotechnical Engineering Report is Based on a Unique Set of Project-Specific Factors
Certerra's geotechnical engineers consider a number of unique, project-specific factors when establishing the scope of a
study. Typical factors include: the clients goals, objectives, and risk management preferences; the general nature of the
structure involved its size, and configuration; the location of the structure on the site; and other planned or existing site
improvements, such as access roads, parking lots, and underground utilities. Unless Certerra, who conducted the study
specifically states otherwise, do not rely on a geotechnical engineering report that 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.
Typical changes that can erode the reliability of an existing geotechnical engineering report include those that affect:
• the function of the proposed structure,as when it's changed,for example,from a parking garage to an office building,
or from a light industrial plant to a refrigerated warehouse,
• elevation, configuration, location, orientation, or weight of the proposed construction,
• alterations in drainage designs; or
• composition of the design team;the passage of time; man-made alterations and construction whether on or adjacent
to the site; or by natural alterations and events, such as floods, earthquakes or groundwater fluctuations; or project
ownership.
Always inform Certerra's geotechnical engineer of project changes—even minor ones—and request an assessment of their
impact. Geotechnical engineers cannot accept responsibility or liability for problems that occur because their reports do
not consider developments of which they were not informed.
Subsurface Conditions Can Change
This geotechnical or geologic report is based on conditions that existed at the time the study was performed. Do not rely
on the findings and conclusions of this report, whose adequacy may have been affected by: the passage of time; by man-
made events, such as construction on or adjacent to the site; or by natural events, such as floods, earthquakes, or
1 Information in this document is based upon material developed by ASFE,Professional Firms Practicing in the Geosciences(asfe.org)
f CERTERRA
f GEOTEST
groundwater fluctuations. Always contact Certerra before applying the report to determine if it is still relevant. A minor
amount of additional testing or analysis will help determine if the report remains applicable.
Most Geotechnical and Geologic Findings are Professional Opinions
Our site exploration identifies subsurface conditions only at those points where subsurface tests are conducted or samples
are taken. Certerra's engineers and geologists review field and laboratory data and then apply their professional judgment
to render an opinion about subsurface conditions throughout the site. Actual subsurface conditions may differ—sometimes
significantly — from those indicated in your report. Retaining Certerra who developed this report to provide construction
observation is the most effective method of managing the risks associated with anticipated or unanticipated conditions.
A Report's Recommendations are Not Final
Do not over-rely on the construction recommendations included in this report. Those recommendations are not final,
because geotechnical engineers or geologists develop them principally from judgment and opinion. Certerra's geotechnical
engineers or geologists can finalize their recommendations only by observing actual subsurface conditions revealed during
construction. Certerra cannot assume responsibility or liability for the report's recommendations if our firm does not perform
the construction observation.
A Geotechnical Engineering or Geologic Report may be Subject to Misinterpretation
Misinterpretation of this report by other design team members can result in costly problems. Lower that risk by having
Certerra confer with appropriate members of the design team after submitting the report. Also, we suggest retaining
Certerra to review pertinent elements of the design teams plans and specifications. Contractors can also misinterpret a
geotechnical engineering report. Reduce that risk by having Certerra participate in pre-bid and preconstruction
conferences, and by providing construction observation.
Do not Redraw the Exploration Logs
Our geotechnical engineers and geologists prepare final boring and testing logs based upon their interpretation of field logs
and laboratory data. To prevent errors of omissions,the logs included in this report should never be redrawn for inclusion in
architectural or other design drawings. Only photographic or electronic reproduction is acceptable; but recognizes that
separating logs from the report can elevate risk.
Give Contractors a Complete Report and Guidance
Some owners and design professionals mistakenly 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 report, but preface it with a clearly written letter of transmittal. In that letter, consider advising the
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 Certerra 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 you be in a position to give contractors the best information available,while requiring them to at least
share some of the financial responsibilities stemming from unanticipated conditions. In addition, it is recommended that a
contingency for unanticipated conditions be included in your project budget and schedule.
Read Responsibility Provisions Closely
Some clients, design professionals, and contractors do not recognize that geotechnical engineering or geology is far less
exact than other engineering disciplines. This lack of understanding can create unrealistic expectations that can lead to
disappointments, claims, and disputes. To help reduce risk, Certerra includes an explanatory limitations section in our
f CERTERRA
f GEOTEST
reports. Read these provisions closely. Ask questions and we encourage our clients or their representative to contact our
office if you are unclear as to how these provisions apply to your project.
Environmental Concerns Are Not Covered in this Geotechnical or Geologic Report
The equipment, techniques, and personnel used to perform an environmental study differ significantly from those used to
perform a geotechnical or geologic study. 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 containments, etc. If you have not yet obtained your own environmental information, ask your
geotechnical consultant for risk management guidance. Do not rely on environmental report prepared for some one else.
Obtain Professional Assistance to Deal with Biological Pollutants
Diverse strategies can be applied during building design, construction, operation, and maintenance to prevent significant
amounts biological pollutants from growing on indoor surfaces. Biological pollutants includes but is not limited to molds,
fungi, spores, bacteria and viruses. To be effective, all such strategies should be devised for the express purpose of
prevention, integrated into a comprehensive plan, and executed with diligent oversight by a professional biological pollutant
prevention consultant. Because just a small amount of water or moisture can lead to the development of severe biological
infestations, a number of prevention strategies focus on keeping building surfaces dry. While groundwater,water infiltration,
and similar issues may have been addressed as part of this study, the geotechnical engineer or geologist in charge of this
project is not a biological pollutant prevention consultant;none of the services preformed in connection with this geotechnical
engineering or geological study were designed or conducted for the purpose of preventing biological infestations.