BLD2024-0560+GEO REPORT+4.26.2024_3.26.37_PM+4222297NELSON GEOTECHNICAL
ASSOCIATES. INC.
BLD2024-0560
September 22, 2023
RECEIVED
Apr 30 2024
CITY OF EDMONDS
DEVELOPMENT SERVICES
DEPARTMENT
April Zepeda & Brian King
c/o Gerald Redding
Via Email: gredding@redarch.net
Geotechnical Engineering Evaluation
Redding Deck Remodel
1225 —11th Place North
Edmonds, Washington
NGA File No. 1462723
Dear April and Brian:
17311-135th Ave. N.E. Suite A-500
Woodinville, WA 98072
(425) 486-1669
www.nelsongeotech.com
This letter summarizes our opinions, evaluation, and recommendations regarding the deck
redevelopment project located at 1225 — 111h Place North in Edmonds, Washington, as shown on the
Vicinity Map in Figure 1. The parcel number for the property is 00606600000900.
INTRODUCTION
The property is square in shape and covers 0.23 acres in area. It is currently occupied by a single-family
residence. The property is bordered by 11th Place North to the east and by neighboring residential
properties to all other sides. Topographically, the site is gently sloping down from east to west and steeply
slopes down to the west on the western edge of the site. We understand the plans include demolishing
the existing deck and constructing a new deck on the west side of the residence. The City of Edmonds has
requested a geotechnical report to address the critical areas mapped within the site.
SCOPE
The purpose of this study is to explore and characterize the site surface and subsurface conditions within
the vicinity of the proposed deck replacement and provide geotechnical recommendations for site
development.
Geotechnical Engineering Evaluation
Redding Deck Remodel
Edmonds, Washington
Specifically, our scope of services included the following:
NGA File No. 1462723
September 22, 2023
Page 2
1. Reviewing available soil and geologic maps of the area as well as other relevant
geotechnical information, as provided.
2. Exploring the subsurface soil and groundwater conditions with hand tool explorations.
3. Mapping the conditions on the site slopes using shallow, hand -tool explorations where
necessary to construct geological cross sections and qualitatively evaluate slope stability.
4. Performing laboratory grain -size sieve analysis on soil samples, as necessary.
5. Determining presence of geological hazards within the site.
6. Providing recommendations for mitigation of geological hazards.
7. Providing general recommendations for site drainage and erosion control, as necessary.
8. Documenting the results of our findings, conclusions, and recommendations in a written
geotechnical letter.
SITE CONDITIONS
Surface Conditions
The property is square in shape and covers 0.23 acres in area. It is currently occupied by a single-family
residence. The property is bordered by 11th Place North to the east and by neighboring residential
properties to all other sides. Topographically, the site is gently sloping down from east to west and is
bordered to the west by a steep west -facing slope. We understand the plans include demolishing the
existing deck and constructing a new deck on the west side of the residence. We measured a cross-section
across the western slope using a hand-held clinometer and a tape measure. The western slope descends
at a gradient of 35 degrees (77.8 percent of slope). The slope is partially covered by grass yard areas as
well as landscaping vegetation, bushes, and young trees. Cross -Section A -A' is presented in Figures 3. We
did not surface water within the site or seepage emitting from site slopes at the time of our visit. We also
did not observe any sloughing or other indications of slope movement during our site visit on August 1,
2023.
NELSON GEOTECHNICAL ASSOCIATES, INC.
Geotechnical Engineering Evaluation
Redding Deck Remodel
Edmonds, Washington
Subsurface Conditions
NGA File No. 1462723
September 22, 2023
Page 3
Geology: The geologic units for this site are shown on The Geologic Map of the Edmonds East and Part of
the Edmonds West Quadrangles, Washington, by James P. Minard (USGS, 1983). The site is mapped as
advance outwash (Qva) with glacial till (Qvt) nearby. Advance outwash is described as well -sorted sand
and gravel deposited by streams issuing from advancing ice sheet. Glacial till is described as a compact
diamict of silt, sand and subrounded to well-rounded gravel. Our shallow explorations encountered silty
fine to medium sand with gravel consistent with the description of glacial till.
Explorations: We visited the site on August 1, 2023, to explore the subsurface conditions within the
vicinity of the proposed deck replacement with three hand auger explorations extending to depths
ranging from 1.5 to 2.5 feet below the existing ground surface. The approximate locations of our
explorations are shown on the Schematic Site Plan in Figure 2. A geologist from Nelson Geotechnical
Associates, Inc. (NGA) completed the explorations, examined the soils and geologic conditions
encountered, and maintained logs of the explorations. The soils were visually classified in general
accordance with the Unified Soil Classification System, presented in Figure 4. The logs of our explorations
are presented as Figure 5. The following paragraph contains a brief description of the subsurface
conditions encountered in the explorations. For a detailed description of the subsurface conditions, the
hand auger logs should be reviewed.
In all of our explorations we encountered dark brown, fine to coarse sand with gravel, organics, roots, and
varying amounts of silt extending to depths in the range of 0.5 to 2.25 feet below the existing ground
surface, which we interpreted as undocumented topsoil. Underlying the topsoil we encountered light
gray, silty, fine to medium sand with gravel which we interpreted as glacial till soils at depth.
Hydrogeologic Conditions
We did not observe any seepage emitting from site slopes or groundwater within our explorations. If
groundwater were to be encountered within the site, we would interpret it to be perched water. Perched
water occurs when surface water infiltrates through less dense, more permeable soils and accumulates
on top of a relatively low permeability material. Perched water does not represent a regional
groundwater "table" within the upper soil horizons. Perched water tends to vary spatially and is
dependent upon the amount of rainfall. We would expect the amount of perched groundwater to
decrease during drier times of the year and increase during wetter periods.
NELSON GEOTECHNICAL ASSOCIATES, INC.
Geotechnical Engineering Evaluation NGA File No. 1462723
Redding Deck Remodel September 22, 2023
Edmonds, Washington Page 4
SENSITIVE AREA EVALUATION
Seismic Hazard
We reviewed the 2018 International Building Code (IBC) for seismic site classification for this project.
Since dense soils are interpreted to underlie the site at depth, the site best fits the IBC description for Site
Class D. Table 1 below provides seismic design parameters for the site that are in conformance with the
2018 IBC, which specifies a design earthquake having a two percent probability of occurrence in 50 years
(return interval of 2,475 years), and the 2008 USGS seismic hazard maps.
Table 1— 2018 IBC Seismic Design Parameters
Site Class
Spectral Acceleration
Spectral Acceleration
Site Coefficients
Design Spectral
at 0.2 sec. (g)
at 1.0 sec. (g)
Response
SS
S1
Parameters
Fa
Fv
Sos
SDI
r -7
D
1.293
0.456
1.000
null
0.862
null
The spectral response accelerations were obtained from the OSHPD Seismic Design Maps website (ASCE
7-16 data) for the project latitude and longitude.
Hazards associated with seismic activity include liquefaction potential and amplification of ground motion.
Liquefaction is caused by a rise in pore pressures in a loose, fine sand deposit beneath the groundwater
table. It is our opinion that the dense glacial deposits interpreted to underlie the site have a low potential
for liquefaction or amplification of ground motion.
Erosion Hazard
The criteria used for determination of the erosion hazard for affected areas include soil type, slope
gradient, vegetation cover, and groundwater conditions. The erosion sensitivity is related to vegetative
cover and the specific surface soil types, which are related to the underlying geologic soil units. The
Natural Resources Conservation Service (NRCS) of the City of Edmonds was reviewed. The soil in the
eastern portion of the site is mapped as Alderwood gravelly sandy loam 15 to 30 percent slopes and the
western portion of the site is mapped as Alderwood-Urban land complex, 8 to 15 percent slopes. The
erosion hazard for these soils are listed as severe and moderate, respectively in areas where soils are
exposed. It is our opinion that the erosion hazard for site soils should be low in areas where the site is not
disturbed, and vegetation remains in place.
Upon review of the Edmonds City Code (ECC) we have determine that site slopes meet the definition of
an erosion hazard area as defined in ECC 23.80.020. A due to their classification by the NRCS as having a
severe erosion hazard.
NELSON GEOTECHNICAL ASSOCIATES, INC.
Geotechnical Engineering Evaluation NGA File No. 1462723
Redding Deck Remodel September 22, 2023
Edmonds, Washington Page 5
Landslide Hazard/Slope Stability
The criteria used for evaluation of landslide hazards include soil type, slope gradient, and groundwater
conditions. The steep slopes within the site descend to the west at gradients of 35 degrees (77.8 percent
grade) and have a vertical relief of approximately 29 feet. Site slopes are vegetated with grass, shrubs,
scattered young to mature trees. We did not observe evidence of surficial sloughing or erosion at the
time of our visit on August 1, 2023. We also did not observe any seepage emitting from site slope while
we were on site.
Upon review of Edmonds City Code (ECC) we have determined that the steep slopes on the west side of
the property meet the definition of a landslide hazard area as outlined in ECC 23.80.020.13, due to the
having inclinations steeper than 40 percent and a height of more than 10 feet. The competent glacial soils
interpreted to form the core of the site slope have high internal strength and are considered stable with
respect to deep-seated slope failures. However, the loose surficial soils on and near the slope have
potential to experience shallow sloughing failures, which could be triggered by intense rainfall or a seismic
event. Proper site grading and drainage as well as slope maintenance, as recommended in this letter,
should help maintain current stability conditions.
CONCLUSIONS AND RECOMDATIONS
General
It is our opinion from a geotechnical standpoint that the proposed deck replacement feasible. Our
explorations in the vicinity of the proposed decks indicated there was 0.5 to 2.25 feet of loose topsoil
underlain by medium dense or better native glacial till soils. These soils should provide adequate support
for foundation loads. We should note that deeper areas of loose or unsuitable soils may be encountered
in unexplored areas of the site. if these conditions are encountered in footing areas they will require over
excavation. We recommend that the replacement deck foundations consist of 12-inch diameter Sonotube
foundations embedded a minimum of one foot into medium dense or better native till soils.
At the time of our site visit the western slope below the existing residence did not exhibit indications of
recent slope instability. We interpreted that the core of the site slope consists of native dense soils, which
are considered stable with respect to deep-seated slope movements. There is a potential for shallow
erosional events to occur within the loose near -surface soils. The proposed setback for the new deck is
approximately 34 feet from the top of the steep slopes. In our opinion this set back should be adequate
to protect the new deck from any failures originated within the steep slopes. Provided the new deck
foundations are constructed per our recommendations, including proper foundation embedment, the
proposed development should not negatively impact slope stability or neighboring properties.
NELSON GEOTECHNICAL ASSOCIATES, INC.
Geotechnical Engineering Evaluation NGA File No. 1462723
Redding Deck Remodel September 22, 2023
Edmonds, Washington Page 6
Under no circumstance should water be allowed to concentrate on or flow over site slopes. Water that is
currently directed below the deck should be collected and routed to a suitable discharge point, away from
the slope.
Earthwork associated with the proposed deck foundation should be minor. However, the soils
encountered on this site are considered moisture -sensitive and may disturb easily when wet. To lessen
the potential impacts of construction on the slopes and to reduce cost overruns and delays, we
recommend that foundation preparation take place during dry weather, if possible. If earthwork takes
place during wet weather, additional expenses and delays should be expected. These extra expenses
could include additional erosion control and temporary drainage measures to protect the slope.
Excavation spoils should be kept away from the slope or hauled off site. Vegetation on the slope should
not be disturbed. Any areas within the site where vegetation is disturbed should be replanted as soon as
reasonably possible.
Erosion Control and Slope Protection
Best Management Practices (BMPs) should be used to control erosion where exposed soils or disturbed
areas are encountered. Erosion control measures may include diverting surface water away from exposed
soils/excavations and the steep site slopes. If any vegetation is removed from the area above the slope,
silt fences or straw bales should be erected to prevent muddy water from flowing over the site slopes.
Disturbed areas should be replanted with vegetation and the vegetation should be maintained until it is
established. Under no circumstances should runoff be allowed to concentrate on the slope either during
construction or after construction has been completed.
Protection of the slope areas should be performed as required by the City of Edmonds. Specifically, we
recommend that the site slopes not be disturbed or modified through placement of any fill or removal of
the existing vegetation. No material of any kind, such as excavation spoils, lawn clippings, debris, and soil
stockpiles, should be placed on or near the slope. The exposed soils underlying the deck should be
protected from erosion. This could be accomplished by placing jute netting across the area or filter fabric
overlain by a thin layer of crushed rock. Any sloping areas disturbed grading activities should be planted
as soon as practical to reduce the potential for erosion. The new vegetation should be maintained until
it is established. Replacement of vegetation should be performed in accordance with the City of Edmonds
code. Under no circumstances should water be allowed to concentrate on the slopes. We recommend
NGA be retained to review final erosion control measures implemented after the fill is removed.
NELSON GEOTECHNICAL ASSOCIATES, INC.
Geotechnical Engineering Evaluation NGA File No. 1462723
Redding Deck Remodel September 22, 2023
Edmonds, Washington Page 7
Site Preparation and Grading
After erosion control measures are implemented, site preparation should consist of stripping the topsoil,
undocumented fill and/or loose soils from foundation areas and other structural areas, to expose medium
dense or better native bearing soils. The stripped soil should be removed from the site or stockpiled for
later use as a landscaping fill. Based on our observations, we anticipate stripping depths of 1.5 to 3.25
feet, depending on the specific locations. However, additional stripping may be required if areas of deeper
undocumented fill and/or loose soil are encountered in unexplored areas of the site.
After site stripping, if the exposed subgrade is deemed loose, it should be compacted to a non -yielding
condition and then proof -rolled with a heavy rubber -tired piece of equipment. Areas observed to pump
or weave during the proof -roll test should be reworked to structural fill specifications or over -excavated
and replaced with properly compacted structural fill or rock spalls. If loose soils are encountered in the
pavement areas, the loose soils should be removed and replaced with rock spalls or granular structural
fill. If significant surface water flow is encountered during construction, this flow should be diverted
around areas to be developed, and the exposed subgrades should be maintained in a semi -dry condition.
If wet conditions are encountered, alternative site stripping and grading techniques might be necessary.
These could include using large excavators equipped with wide tracks and a smooth bucket to complete
site grading and covering exposed subgrade with a layer of crushed rock for protection. If wet conditions
are encountered or construction is attempted in wet weather, the subgrade should not be compacted as
this could cause further subgrade disturbance. In wet conditions, it may be necessary to cover the exposed
subgrade with a layer of crushed rock as soon as it is exposed to protect the moisture sensitive soils from
disturbance by machine or foot traffic during construction. The prepared subgrade should be protected
from construction traffic and surface water should be diverted around areas of prepared subgrade.
Structure Setbacks
Uncertainties related to building along steep slopes are typically addressed by the use of building setbacks.
The purpose of the setback is to establish a "buffer zone" between the structure and the top of the slope
so that ample room is allowed for normal slope recession during a reasonable life span of the structure.
In a general sense, the greater the setback, the lower the risk of slope failures to impact the structure.
From a geological standpoint, the setback dimension is based on the slope's physical characteristics, such
as slope height, slope gradient, soil type, and groundwater conditions. Other factors such as historical
slope activity, rate of regression, and the type and desired life span of the development are important
considerations as well. We understand the proposed structure will be constructed close to the top of site
slopes.
NELSON GEOTECHNICAL ASSOCIATES, INC.
Geotechnical Engineering Evaluation NGA File No. 1462723
Redding Deck Remodel September 22, 2023
Edmonds, Washington Page 8
Based upon the conditions described above, it is our opinion that the potential for shallow sloughing -type
failures exists on the steeper site slopes, while the potential for deep-seated failures is considered low.
In our opinion the proposed setback of 34-feet from the top of the steep slope should provide adequate
separation from the slope, in the event of shallow failures during a reasonable life span of the structure.
We should be retained to review final structure locations and to observe foundation excavations prior to
placing forms. Any proposed development within the setback area should be the subject of a specific
geotechnical evaluation. Under no circumstances should water be allowed to concentrate on the slopes,
during or after construction.
Deck Foundations
We recommend the new deck be supported on sonotubes extending below the surface. Our soil
explorations indicated competent native soils should be encountered at depths in the range of 0.5 to 2.25
feet below existing grade; however, this could be deeper in unexplored areas of the site. Deck foundations
should extend through any loose undocumented fill encountered and be founded in competent native
soils. We recommend deck foundations be supported on 12-inch minimum diameter sonotubes extending
a minimum 24 inches below the existing ground surface but no less than 1-foot embedded into competent
native soils. The sonotubes should be analyzed for design soil bearing pressure of 1500 pounds per square
foot (psf).
A passive earth pressure of 150 pounds per cubic foot should be utilized in designing the deck foundations
along the below grade portions of the deck foundations. Using the above passive pressure, the upper 1-
foot of soil should be neglected in the design. We anticipate the embedded sonotube foundations should
provide adequate protection from shallow erosional slide activity as well as vertical and lateral loading
thresholds. If during structural design passive earth pressure is not sufficient to support the planned loads,
we recommend grouted tieback anchors be utilized to pick up lateral loads for each planned sonotube
foundation. We should be retained to review final plans and inspect the bottom of hole subgrade prior
to placing the sonotube foundation.
NELSON GEOTECHNICAL ASSOCIATES, INC.
Geotechnical Engineering Evaluation
Redding Deck Remodel
Edmonds, Washington
NGA File No. 1462723
September 22, 2023
Page 9
Site Drainage
We do not anticipate that the new decks will significantly alter drainage patterns at the site. Adequately
spaced decking on joist framing should not concentrate runoff from the deck. If the decking is tightly
spaced and will concentrate runoff from the decks, the water should be collected in gutters and
downspouts and be directed away from the slope. We should be retained to evaluate the drainage plans.
The soil below the deck should be covered with erosion control matting. All runoff generated on this site,
including roof downspouts, yard and footing drains, and hard surfaces, should be collected and routed
into permanent discharge system at the bottom of the slope or an existing, approved system. Under no
circumstances should water be allowed to flow uncontrolled over the slopes. All existing drainage
systems should be inspected and maintained such that no water is allowed to reach the slope. Water
should not be allowed to collect in any area where foundations are to be constructed.
USE OF THIS LETTER
This letter has been prepared for April Zepeda and Brian King and associated agents, for use in the
planning and design of the proposed deck developments on this site only. The scope of our work does
not include services related to construction safety precautions and our recommendations are not
intended to direct the contractors' methods, techniques, sequences, or procedures, except as specifically
described in our letter. There are possible variations in subsurface conditions between the explorations
and also with time. Our letter, conclusions, and interpretations should not be construed as a warranty of
subsurface conditions. A contingency for unanticipated conditions should be included in the project
budget and schedule.
We recommend that NGA be retained to provide monitoring and consultation services 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 differ from
those anticipated, and to evaluate whether or not deck support installation complies with our
recommendations. We should be contacted a minimum of one week prior to construction activities.
All people who own or occupy homes on or near hillsides should realize that landslide movements are
always a possibility. The landowner should periodically inspect the slope, especially after a winter storm.
If distress is evident, a geotechnical engineer should be contacted for advice on remedial/preventative
measures. The probability that landsliding will occur is substantially reduced by the proper maintenance
of drainage control measures at the site. Therefore, the homeowner should take responsibility for
performing such maintenance.
NELSON GEOTECHNICAL ASSOCIATES, INC.
Geotechnical Engineering Evaluation
Redding Deck Remodel
Edmonds, Washington
NGA File No. 1462723
September 22, 2023
Page 10
Within the limitations of scope, schedule and budget, our services have been performed in accordance
with generally accepted geotechnical engineering practices in effect in this area at the time this letter was
prepared. No other warranty, expressed or implied, is made. Our observations, findings, and opinions
are a means to identify and reduce the inherent risks to the owner.
NELSON GEOTECHNICAL ASSOCIATES, INC.
Geotechnical Engineering Evaluation
Redding Deck Remodel
Edmonds, Washington
NGA File No. 1462723
September 22, 2023
Page 11
We appreciate the opportunity to provide service to you on this project. If you have any questions or
require further information, please call.
Sincerely,
NELSON GEOTECHNICAL ASSOCIATES, INC.
Faith K. Stelter
Staff Geologist I
Sarah L. Dunn, GIT
Project Geologist
.2023
Khaled M. Shawish, PE
Principal Engineer
SLD:FKS:KMS:dy
Five Figures Attached
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Vicinity Map
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Site Plan
LEGEND
HA-1
• — Property line _�_ Number and approximate
location of hand auger
A A' Approximate location
of cross-section
Reference: Site plan based on field measurements, observations, and aerial parcel map review.
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UNIFIED SOIL CLASSIFICATION SYSTEM
GROUP
MAJOR DIVISIONS
GROUP NAME
SYMBOL
CLEAN
GW
WELL -GRADED, FINE TO COARSE GRAVEL
COARSE-
GRAVEL
GRAVEL
GP
POORLY -GRADED GRAVEL
GRAINED
MORE THAN 50 %
GRAVEL
GM
SILTY GRAVEL
OF COARSE FRACTION
RETAINED ON
SOILS
NO.4 SIEVE
WITH FINES
GC
CLAYEY GRAVEL
SAND
CLEAN
SW
WELL -GRADED SAND, FINE TO COARSE SAND
SAND
SP
POORLY GRADED SAND
MORE THAN 50 %
RETAINED ON
MORE THAN 50 %
NO. 200 SIEVE
OF COARSE FRACTION
SAND
SM
SILTY SAND
PASSES NO. 4 SIEVE
WITH FINES
SC
CLAYEY SAND
FINE -
SILT AND CLAY
ML
SILT
INORGANIC
GRAINED
LIQUID LIMIT
CL
CLAY
LESS THAN 50 %
SOILS
ORGANIC
OL
ORGANIC SILT, ORGANIC CLAY
SILT AND CLAY
MH
SILT OF HIGH PLASTICITY, ELASTIC SILT
INORGANIC
MORE THAN 50 %
PASSES
LIQUID LIMIT
CH
CLAY OF HIGH PLASTICITY, FAT CLAY
NO. 200 SIEVE
50 % OR MORE
ORGANIC
OH
ORGANIC CLAY, ORGANIC SILT
HIGHLY ORGANIC SOILS
PT
PEAT
NOTES:
1) Field classification is based on visual SOIL MOISTURE MODIFIERS:
examination of soil in general
accordance with ASTM D 2488-93. Dry - Absence of moisture, dusty, dry to
the touch
2) Soil classification using laboratory tests
is based on ASTM D 2488-93. Moist - Damp, but no visible water.
3) Descriptions of soil density or Wet - Visible free water or saturated,
consistency are based on usually soil is obtained from
interpretation of blowcount data, below water table
visual appearance of soils, and/or
test data.
Project Number
nELSOn GEOTEnninl_
No.
Date
Revision
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ASSOCIATES, inc
ui " 135th"°e CA Wenatchee Office
17311-1351h Ave. NE, A-500 105 Palouse
Figure 4
Woodinville, WA 98072 Wenatchee, WA 98801
98
www.nelsongeoiech.com (425) 486-1669 / Fax 481-2510 (509) 665-7696 / Fax: 665-7692
LOG OF EXPLORATION
DEPTH (FEET) USCS SOIL DESCRIPTION
HAND AUGER
ONE
0.0-0.5 GRASS UNDERLAIN BY BROWN -GREY, FINE TO MEDIUM SAND WITH SILT, ROOTS,
AND GRAVEL (LOOSE TO MEDIUM DENSE, DRY TO MOIST) (FILL)
0.5 - 1.5 SM LIGHT GREY, SILTY, FINE TO MEDIUM SAND WITH GRAVEL
(MEDIUM DENSE TO DENSE, MOIST)
SAMPLES WERE NOT COLLECTED
GROUNDWATER SEEPAGE WAS NOT ENCOUNTERED
HAND AUGER CAVING WAS NOT ENCOUNTERED
HAND AUGER MET REFUSAL AT 1.5 FEET
HAND AUGER
TWO
0.0- 1.0 LANDSCAPING UNDERLAIN BY DARK BROWN TOPSOIL
1.25 - 2.25 DARK GREY -BROWN, SILTY, FINE TO COARSE SAND WITH ORGANICS, ROOTS,
GRAVEL, AND IRON OXIDE STAINING (LOOSE TO MEDIUM DENSE, MOIST) (FILL)
2.25-2.5 SM LIGHT GREY, SILTY, FINE TO MEDIUM SAND WITH GRAVEL (MEDIUM DENSE TO
DENSE, MOIST)
SAMPLES WERE NOT COLLECTED
GROUNDWATER SEEPEGE WAS NOT ENCOUNTERED
HAND AUGER CAVING WAS NOT ENCOUNTERED
SAMPLES WERE NOT COLLECTED
HAND AUGER
THREE
0.0-0.5 GRASS UNDERLAIN BY BROWN -GREY, FINE TO MEDIUM SAND WITH SILT, ROOTS,
AND GRAVEL (LOOSE TO MEDIUM DENSE, DRY TO MOIST) (FILL)
0.5 - 1.5 SM LIGHT GREY, SILTY, FINE TO MEDIUM SAND WITH GRAVEL
(MEDIUM DENSE TO DENSE, MOIST)
SAMPLES WERE NOT COLLECTED
GROUNDWATER SEEPAGE WAS NOT ENCOUNTERED
HAND AUGER CAVING WAS NOT ENCOUNTERED
HAND AUGER MET REFUSAL AT 1.5 FEET
DJO:ABT NELSON GEOTECHNICAL ASSOCIATES, INC.
FILE NO 1462723
FIGURE 5