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Parcel #322353190040
9110 East SR 106
Union, Washington
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Submitted to:
Bubba and Lynn Vandling
9110 East SR 106
Union, Washington
31-96W
Submitted by:
E3RA, Inc.
PO Box 44840
Tacoma, Washington 98448
June 8, 2011
T11055
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TABLE OF CONTENTS RECEIVED
ED
JUL 2 1 2011
426 W. CEDAR Sr
F�'age No.
1.0 SITE AND PROJECT DESCRIPTION..................................................................................1
2.0 EXPLORATORY METHODS................................................................................................2
3.0 SITE CONDITIONS..............................................................................................................2
3.1 Surface Conditions ...................................................................................................2
3.2 Soil Conditions..........................................................................................................3
3.3 Groundwater Conditions...........................................................................................4
3.4 Seismic Conditions...................................................................................................4
3.5 Liquefaction Potential ..............................................................................................4
3.6 Slope Stability Analysis ............................................................................................4
4.0 CONCLUSIONS AND RECOMMENDATIONS.....................................................................5
4.1 Site Preparation........................................................................................................6
4.2 Concrete Foundations ..............................................................................................7
4.4 Structural Fill ............................................................................................................8
5.0 RECOMMENDED ADDITIONAL SERVICES .......................................................................9
6.0 CLOSURE..........................................................................................................................10
List of Tables
Table 1. Approximate Locations and Depths of Exploration........................................................................2
Table 2. Estimated Properties of On-site Soils for Stability Analysis...........................................................5
List of Figures
Figure 1. Topographic and Location Map
Figure 2. Site Plan
Figure 3. Geologic Cross Section A-A'
APPENDICIES
APPENDIX A
Soils Classification Chart and Key to Test Data........................................................................................A-1
Logof Test Hole TH-1 ...............................................................................................................................A-2
APPENDIX B
Slope Stability Analysis
PO Box 44840
Tacoma,WA 98448
253-537-9400
253-537-9401 Fax
E3RA
June 8,2011
T11055
Bubba and Lynn Vandling
9110 East SR 106
Union,Washington
c/o Sheldon Smith
CBay Consulting
3043 Center Street
Tacoma, WA,98409
Subject: Geotechnical Report
Parcel#322353190040
9110 East SR 106
Union,Washington
Dear Mr.and Mrs.Vandling:
E3RA is pleased to submit this Geotechnical Report for your residential site. The purpose of our Report
is to address Title 17 of Mason County Critical Areas Ordinances as they relate to landslide and erosion
hazards on the site.
Our scope of services is limited to surface observations, subsurface probes, geologic research, and letter
preparation. This report has been prepared for the exclusive use of Bubba and Lynn Vandling, and their
consultants, for specific application to this project in accordance with generally accepted geotechnical
practice.
1.0 SITE AND PROJECT DESCRIPTION
The project site is a 0.28 acre, irregularly-shaped parcel that is located on the south side of East SR 106
east of Union, Washington, as shown on our Topographic and Location Map (Figure 1). The site fronts
the state highway for a distance of 108'/z feet and extends away from the highway right of way (south)
about 93 feet. The site is bordered by open land to the south and east and by residences to the north and
west.
Currently a modular home,with decking on the north and east sides,occupies the central part of the site;a
detached garage occupies the northwest part of the site;a septic system occupies the east part of the site; a
rockery, comprised of two 4 foot high tiers, is located along the west boundary; and a 4 to 5 foot high
rockery occupies the south boundary area..
Plans call for the removal of the existing modular home and decks and replacement with,generally within
the old home footprint, a new two-story, 32 by 52 feet new, conventional, stick-built home with a joist
supported floor system. The new home will be located approximately 12 feet from a rockery located near
the toe of a steep slope. The existing septic system will be used for the new home. Roof runoff will be
directed to a drywell west of he planned new home. The attached Site Plan, Figure 2, approximates the
location of the existing septic system,rockeries,drywell,nearby slopes,and planned new residence.
June 8, 2011 ORA, Inc.
T11055/Vandling Geotechnical Report
2.0 EXPLORATORY METHODS
We observed site and subsurface conditions on May 25, 2011. Our evaluation program for the project
comprised the following elements:
• A surface reconnaissance of the site and nearby areas, including observation of native
soils exposed onsite and nearby offsite;
• Probing of soils in the vicinity of the planned construction;
• Hand excavation of an exploratory test hole in the vicinity of the planned construction,
and;
• A review of published geologic and seismologic maps and literature.
Table 1 summarizes the approximate functional location and termination depth of our probes and Figure 2
depicts the approximate their relative location.
TABLE 1
APPROXIMATE LOCATION AND DEPTH OF EXPLORATION
Exploration Functional Location Termination
Depth
TH-1 West of existing building 12 inches
3.0 SITE CONDITIONS
The following sections present our observations, measurements, findings, and interpretations regarding,
surface, soil,groundwater, seismic,liquefaction,and slope conditions.
3.1 Surface Conditions
The site is,for the most part,relatively level.A steep slope,with average grades we estimate at 65 percent
and which forms the south wall of the Hood Canal Basin, rises 400 to 500 feet from the south boundary
area. It appears that the southernmost 20 feet or so of the site was graded so that the toe of the slope was
moved somewhat to the south.
Slopes at the east boundary area of the site are moderately steep and rise to the east about 20 feet. Slopes
at the west boundary area, which are defended and supported by two 4 foot high rockeries, rise 8 or 10
feet to the west,to a neighboring,relatively level, residential site. Slopes are relatively level to the north,
across East SR 106,where a residential site extends north to the shoreline of Hood Canal.
Slopes on adjacent properties to the east and west are similar to those onsite in that the wall of the Hood
Canal Basin rises steeply to the south.
A ravine opens to the north from the steep south wall of Hood Canal,just southwest of the site. A rip-rap
lined ditch extends onto the southwest corner of the site from the ravine mouth. The ditch channels water
from the ravine north across the site during periods of heavy rainfall.
A small alluvial fan, apparently deposited a few years ago from flow from the ravine, spreads across a
portion of the southwest corner of the site. Alluvial fans are deposited during periods of severe rainfall.
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T11055/Vandling Geotechnical Report
According to the owner, the alluvial fan was deposited a few years ago, likely in early December, 2007,
when 10 inches or more rain fell in the general area over a two day period.
We observed,geomorpologically,that the most of the site is a small shoreline terrace that was eroded into
the wall of the Hood Canal Basin after the retreat of the last glacier to affect the area,the Vashon Glacier.
The steep slope to the south, the Hood Canal Basin wall, is comprised of well consolidated glacial
advance outwash deposits. These steep slopes were incised by glacial melt water, released from melting
of the Vashon Glacier, into ravines that open out to the north toward Hood Canal.The upland south of the
steep south wall of Hood Canal can be described as an upland glacial till plain with localized surficial
deposits of recessional glacial outwash.
We did not observe upland water bodies or wetlands near the site, nor does the wetland GIS layer of the
Mason County Viewer depict nearby wetlands.
No seeps, springs or other surface expressions of groundwater were observed on site. No streams,
channels,or other signs of surface flow were observed on the site,other than the rip-rap lined ditch on the
southwest part of the site. The ditch, and the area upslope from the ditch at the mouth of the ravine, was
dry during our site reconnaissance and likely flows only during periods of intense rainfall.
Vegetation onsite is comprised mostly of grass, although some ornamental shrubbery has been planted on
the east part of the site. Just south of the site, where have it appears that the toe of the steep slope to the
south has been graded out, vegetation consists of smaller cedars, firs, alders and maples which have
diameters of 14 inches or less. The remainder of the steep hillside near the site consists of a mature fir-
cedar forest that is typical of this part of the Pacific Northwest.
Slight sloughing appears to have occurred, within the last 30 years or so, on the lowermost 30 feet of the
steep slope immediately south of the site, where the toe of the slope was moved during original site
grading. As previously mentioned, a 4 to 5 foot high rockery has been constructed at the toe of the slope
there. No recent sloughing has occurred, and trees 14 inches or less in diameter are now growing there.
Most of the small trees in this area are bent at their bases, indication that slow soil creep is occurring.
Slow soil creep occurs only on the surface of the slope, in the upper few feet of soil, and does not signal
that slopes are deeply unstable.
We did not observe indicators of recent, ancient,or incipient landslides,such as seeps,hummocky terrain,
tension cracks, scarps,tilted trees,etc.,on the site or within a few hundred feet of the site.
The Coastal Zone Atlas classifies the site as S, Stable. The nearby slopes adjacent to the site are
classified as I, Intermediate. Intermediate slopes are generally over 15 percent in grade with no known
slope failures.
3.2 Soil Conditions
Soils exposed in the hill side offsite to the south, about 30 feet upslope from the existing building, are
comprised of very dense sandy gravel with some silt. Soils in our shallow test hole west of the existing
building revealed dense sandy gravel with trace silt. Probing of soils near the existing building found
them to be firm and non-yielding at depths of less than 1 foot.
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June 8, 2011 E3RA, Inc.
T11055/Vandling Geotechnical Report
The Coastal Zone Atlas maps soils on the site as Qpg, Pleistocene gravel deposited before the arrival of
the Vashon Glacier. The same source maps soils in nearby slopes as Qa, Vashon advance outwash,
comprised of sand and gravel deposited in advance of the Vashon Glacier. Our test hole exploration, and
observation of soils exposed in the steep slope south of the site, corroborates the mapped stratigraphy. It
is our experience that pre-Vashon Pleistocene gravels are welded by oxidization and are more cohesive
than are non-oxidized gravel deposits.
The enclosed exploration log (Appendix A) provides a description of the soil strata encountered in our
test hole. Our interpretation of the soil stratigraphy on the site and the lower part of the slope to the south
is depicted in Geologic Profile A-A' (Figure 3).
33 Groundwater Conditions
No seeps, springs, or other surface expressions of groundwater were observed on the site or on the steep
slopes near the site. Because of the rapidly permeable nature of site soils, it is unlikely that groundwater
rises to levels that will be encountered during excavations for the new home.
3.4 Seismic Conditions
Based on our classification of onsite soils and our review of published geologic maps,we interpret the on
site soil conditions to correspond with class C, as defined by Table 1613.5.2 of the 2009 International
Building Code (IBC).
3.5 Liquefaction Potential
Liquefaction is a sudden increase in pore water pressure and a sudden loss of soil shear strength caused by
shear strains, as could result from an earthquake. Research has shown that saturated, loose sands with
fines (silt and clay) content less than about 20 percent are most susceptible to liquefaction. The glacial
deposits that underlie the site that comprise nearby slopes have been over-ridden by the Vashon glacier
and are too well consolidated to easily liquefy.
3.6 Slone Stability Analysis
We analyzed the slope stability under selected conditions. The following sections describe our method of
analysis and present our results.
Slope stability analyses typically involve five basic slope parameters: (1) location and shape of the
potential failure surface, (2) internal friction angle of the various soils, (3) cohesion of the various soils,
(4) density of the various soils, and (5) location of the piezometric groundwater surface. Once all five
parameters have been estimated,the critical slip surface and associated safety factor of a given slope can
be calculated. A critical slip surface is defined as the most likely surface along which a soil mass will
slide,and a safety factor is defined as the ratio of the sum of all moments resisting slope movement versus
the sum of all moments tending to cause slope movement. Consequently, a slope that possesses a safety
factor of 1 is on the verge of sliding, whereas a slope with a safety factor greater than 1 has some
resistance to sliding. According to standard geotechnical engineering practice,a static safety factor of 1.5
and a seismic safety factor of 1.1 are considered the desirable minimum values for most slopes, but 1.25
and 1.01,respectively,are often regarded as acceptable values.
Slope stability conditions for the project site were analyzed by means of Bishop Circular Analysis. All
calculations were performed utilizing the computer program WINSTABLE and are attached in
Appendix B.
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June 8, 2011 E3RA, Inc.
T11055/Vandling Geotechnical Report
Our site observations and geologic research indicate that the soils in the nearby steep slope consist of
sandy advance glacial outwash and soils underling the planned construction consist of pre-Vashon
gravels. Both soils have been glacially over-ridden,so are relatively stable with respect to slopes. We did
not see evidence that the two soil types just discussed are underlain by impermeable soils, which, in the
Puget Sound and Hood Canal region,can indicate a potential for unstable slopes.
Our estimated values of internal friction angle, cohesion, and density soils onsite and in the steep slope
south of the site are listed in Table 2. To model the foundation load applied by the residence,we applied
a vertical force of 2,000 pounds per square foot. We analyzed slope conditions generally along the
alignment of Geologic Profile A-A' (Figure 3).
Our analysis yielded a Seismic Factor of Safety of 1.21 and a Static Factor of Safety of 1.53.
TABLE 2
ESTIMATED PROPERTIES OF ON-SITE SOILS FOR STABILITY ANALYSIS
Soil Type Density Cohesion Internal Friction Angle
(pcl7 (psll (degrees)
Glacial Advance Outwash 125 50 42
Pleistocene Gravel 125 50 38
4.0 CONCLUSIONS AND RECOMMENDATIONS
Plans call for the construction of a new residence and garage approximately 25 feet from the top of a
moderately steep slope. We offer the following general geotechnical conclusions and recommendations
concerning this project.
• Landslide Hazards: In our opinion,based on our site observations,geologic research,and
our Slope Analysis, the site is globally stable. The planned new building will not
adversely affect slope stability on the site.
• Erosion Hazards: Grades in the area of construction are relatively level and well
consolidated, so present only a slight erosion hazard. Nonetheless, we recommend that a
silt fence be placed on the level, upland part of the site near top of the slope to the west.
Specific recommendations for silt fences are provided in the Section 4.1. The rip-rap
lined ditch appears to be sufficient to channel water as it emerges from the southwest
corner of the site after intense rainfall, but it should be monitored so that it is kept clear
and does not plug with alluvial deposits and debris.
• Foundation Sub es: Foundations should bear on medium dense or denser native soils,
which we are present within a foot or two of the surface of the site.
• Buffers and Setbacks: Current plans call for the south side of the planned home to be 12
feet or so from a rockery at the toe of the steep slope located just south of the site. In our
opinion,this setback is sufficient.
Because grades on the site are mostly level or moderate in grade, we do not recommend
vegetative buffers or other setbacks.
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June 8, 2011 E3RA, Inc.
T11055!Vandling Geotechnical Report
• Groundwater: Surface expressions of groundwater were not observed onsite. It is our
opinion that groundwater does not currently affect slope stability on site or nearby off
site,and,based on observations onsite and nearby offsite,that groundwater will not affect
the planned construction.
• Bearing_Soils: Firm bearing soils are within a foot or two of the surface in the vicinity of
the planned construction.
• Disposal of Collected Storm Water: Stormwater will be disposed of in a drywell located
west of the planned structure, away from slopes. In our opinion, the drywell is in a
favorable location for the disposal of storm water.
• Septic Drain Field Placement: An approved septic drain field is already in place east of
the planned construction.
• Onsite and Offsite Impact of Planned Development: Because the buildings will be
constructed on level terrain and because the site is underlain by firm, glacially over-
ridden granular soils,the impact to slope stability and to the potential for erosion, both
off site and on site will not be significant,provided our recommendations are followed.
• Clearing and Grading Plan: No clearing of vegetation is planned for the site nor is
significant grading, which will consist mostly of excavations for the foundation,planned.
We do not recommend a clearing and grading plan unless specifically called for by
Mason County, provided the recommendations in this report are followed. Bare soils
exposed during the construction process should be re-vegetated as soon as possible after
construction is complete.
The following sections present our specific geotechnical conclusions and recommendations concerning
site preparation, concrete foundations, and structural fill. The Washington State Department of
Transportation (WSDOT) Standard Specifications and Standard Plans cited herein refer to WSDOT
publications M41-10, 1996 Standard Specifications for Road, Bridge, and Municipal Construction, and
M21-01,Standard Plans for Road, Bridge, and Municipal Construction,respectively.
4.1 Site Preparation
Preparation of the project site should involve erosion control, temporary drainage, cutting, filling,
excavations,and subgrade compaction.
Erosion Control: Before new construction begins, an appropriate erosion control system should be
installed. This system should collect and filter all surface water runoff through silt fencing. We
anticipate a system of berms and drainage ditches around construction areas will provide an adequate
collection system. Silt fencing fabric should meet the requirements of WSDOT Standard
Specification 9-33.2 Table 3. In addition, silt fencing should embed a minimum of 6 inches below
existing grade. An erosion control system requires occasional observation and maintenance. Specifically,
holes in the filter and areas where the filter has shifted above ground surface should be replaced or
repaired as soon as they are identified.
Temporary Drainage: We recommend intercepting and diverting any potential sources of surface or
near-surface water within the construction zones before stripping of surficial organic soils begins.
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June 8, 2011 E3RA. Inc.
T11055/Vandling Geotechnical Report
Because the selection of an appropriate drainage system will depend on the water quantity, season,
weather conditions, construction sequence, and contractor's methods, final decisions regarding drainage
systems are best made in the field at the time of construction. Based on our current understanding of the
construction plans, surface and subsurface conditions, we anticipate that curbs, berms, or ditches placed
around the work areas will adequately intercept surface water runoff.
Clearing and Stripping: After surface and near-surface water sources have been controlled, any sod,
topsoil,and root-rich soil should be stripped from the building area. Stripping is best performed during a
period of dry weather
Site Excavations and Utility Trenches: Based on our explorations, we expect that excavations will
encounter medium dense to dense gravelly soils. Conventional backhoes and excavators should be
adequate for the excavation of site soils.
Dewatering: We do not anticipate that groundwater would be encountered during site excavations.
Onsite Soils: We offer the following evaluation of these on-site soils in relation to potential use as
structural fill:
• Surficial Organic Soils: Sod,topsoil, and forest duff are not suitable for use as structural
fill under any circumstances, due to their high organic content. Consequently, these
materials can be used only for non-structural purposes,such as in landscaping areas.
• Pleistocene Pre-Vashon Gravel: The sandy, gravelly soils that underlie the site can be
reused as structural fill, provided any particles larger than 6 inches are removed and any
significant organics are removed.
Temporary Cut Slopes: All temporary cut slopes in site soils should be no steeper than V/z H:1 V, and
should conform to Washington Industrial Health and Safety Act(WISHA)regulations.
Subgrade Compaction: Subgrade soils probed during our reconnaissance were firm and non-yielding.
Generally, we recommend that any localized zones of looser soils observed within subgrades be
compacted to a density commensurate with the surrounding soils. Any pumping soils observed within a
subgrade should be overexcavated and replaced with a suitable structural fill material.
Permanent Slopes: All permanent cut slopes and fill slopes should be adequately inclined to reduce
long-term raveling, sloughing, and erosion. We generally recommend that no permanent slopes be
steeper than 2H:1 V. For all soil types, the use of flatter slopes (such as 21/2H:l V) would further reduce
long-term erosion and facilitate re-vegetation.
Slope Protection: A hardy vegetative groundcover should be established as soon as feasible, to further
protect any bare sloped areas from the potential from runoff water erosion. Alternatively, permanent
slopes could be armored with quart'spalls or a geosynthetic erosion mat.
4.2 Concrete Foundations
Conventional spread footings or column footings could provide adequate support for the planned new
building,in our opinion. We offer these general recommendations.
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June 8, 2011 ORA, Inc.
T11055/Vandling Geotechnical Report
Footing Depths and Widths: For frost and erosion protection, the bases of all exterior footings should
bear at least 18 inches below adjacent outside grades, whereas the bases of interior footings need bear
only 12 inches below the surrounding slab surface level. To reduce post-construction settlements,
continuous(wall)and isolated(column)footings should be at least 18 and 24 inches wide,respectively.
Bearing Subgrades: Footings should bear on medium dense or denser, undisturbed native soils which
have been stripped of surficial organic soils, or on properly compacted structural fill which bears on
undisturbed native soils which have been stripped of surficial organic soils. Firm bearing soils will likely
be found within a foot or two of the surface.
In general,before footing concrete is placed,any localized zones of loose soils exposed across the footing
subgrades should be compacted to a firm, unyielding condition, and any localized zones of soft,organic,
or debris-laden soils should be overexcavated and replaced with suitable structural fill.
Subgrade Observation: All footing subgrades should consist of firm, unyielding,native soils or structural
fill materials compacted to a density of at least 95 percent (based on ASTM:D-1557). Footings should
never be cast atop loose,soft, or frozen soil, slough, debris,existing uncontrolled fill,or surfaces covered
by standing water.
Bearing Pressures: In our opinion, for static loading, footings that bear on properly prepared subgrades
can be designed for a maximum allowable soil bearing pressure of 2,000 psf. A one-third increase in
allowable soil bearing capacity may be used for short-term loads created by seismic or wind related
activities.
Footing Settlements: Assuming that subgrades are prepared as outlined above and that any structural fill
soils used an are compacted to a medium dense or denser state, we estimate that total post-construction
settlements of properly designed footings bearing on properly prepared subgrades will not exceed 1 inch.
Differential settlements for comparably loaded elements may approach one-half of the actual total
settlement over horizontal distances of approximately 50 feet.
Footing Backfill: To provide erosion protection and lateral load resistance, we recommend that all
footing excavations be backfilled on both sides of the footings and stemwalls after the concrete has cured.
Either imported structural fill or non-organic onsite soils can be used for this purpose, contingent on
suitable moisture content at the time of placement. Regardless of soil type,all footing backfill soil should
be compacted to a density of at least 90 percent(based on ASTM:D-15 5 7).
Lateral Resistance: Footings that have been properly backfilled as recommended above will resist lateral
movements by means of passive earth pressure and base friction. We recommend using an allowable
passive earth pressure of 250 psf for the gravelly soils onsite and an allowable base friction coefficient of
0.35
43 Structural Fill
The term "structural fill" refers to any placed under foundations, retaining walls, slab-on-grade floors,
sidewalks, pavements, and other structures. Our comments, conclusions, and recommendations
concerning structural fill are presented in the following paragraphs.
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June 8, 2011 E3RA, Inc.
T11055 /Vandling Geotechnical Report
Materials: Typical structural fill materials include clean sand, gravel, pea gravel, washed rock, crushed
rock, well-graded mixtures of sand and gravel (commonly called "gravel borrow" or "pit-run"), and
miscellaneous mixtures of silt, sand,and gravel. Recycled asphalt,concrete,and glass,which are derived
from pulverizing the parent materials, are also potentially useful as structural fill in certain applications.
Soils used for structural fill should not contain any organic matter or debris, nor any individual particles
greater than about 6 inches in diameter.
Fill Placement: Clean sand, gravel, crushed rock, soil mixtures, and recycled materials should be placed
in horizontal lifts not exceeding 8 inches in loose thickness,and each lift should be thoroughly compacted
with a mechanical compactor.
Compaction Criteria: Using the Modified Proctor test(ASTM D-1557)as a standard,we recommend that
structural fill used for various onsite applications be compacted to the following minimum densities:
Fill Application Minimum Compaction
Footing subgrade and bearing pad 95 percent
Foundation and subgrade wall backfill 90 percent
Slab-on-grade floor subgrade and subbase 95 percent
Subgrade Observation and Compaction Testing: Regardless of material or location, all structural fill
should be placed over firm,unyielding subgrades prepared in accordance with the Site Preparation section
of this report. The condition of all subgrades should be observed by geotechnical personnel before filling
or construction begins. Also, fill soil compaction should be verified by means of in-place density tests
performed during fill placement so that adequacy of soil compaction efforts may be evaluated as
earthwork progresses.
Soil Moisture Considerations: The suitability of soils used for structural fill depends primarily on their
grain-size distribution and moisture content when they are placed. As the "fines" content (that soil
fraction passing the U.S. No. 200 Sieve) increases, soils become more sensitive to small changes in
moisture content. Soils containing more than about 5 percent fines (by weight) cannot be consistently
compacted to a firm, unyielding condition when the moisture content is more than 2 percentage points
above or below optimum. For fill placement during wet-weather site work,we recommend using "clean"
fill, which refers to soils that have a fines content of 5 percent or less (by weight) based on the soil
fraction passing the U.S.No.4 Sieve.
5.0 RECOMMENDED ADDITIONAL SERVICES
Because the future performance and integrity of the structural elements will depend largely on proper site
preparation, drainage, fill placement,and construction procedures, monitoring and testing by experienced
geotechnical personnel should be considered an integral part of the construction process. Consequently,
we recommend that E3RA be retained to provide the following post-report services:
• Review all construction plans and specifications to verify that the design criteria
presented in this report have been properly integrated into the design;
• Prepare a letter summarizing all review comments(if required by Mason County);and
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June 8, 2011 ORA, Inc.
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• Prepare a post-construction letter summarizing all field observations,inspections,and test
results(if required by Mason County).
6.0 CLOSURE
The conclusions and recommendations presented in this report are based, in part,on the explorations that
we observed for this study;therefore, if variations in the subgrade conditions are observed at a later time,
we may need to modify this report to reflect those changes. Also, because the future performance and
integrity of the project elements depend largely on proper initial site preparation, drainage, and
construction procedures, monitoring and testing by experienced geotechnical personnel should be
considered an integral part of the construction process. E3RA is available to provide geotechnical
monitoring of soils throughout construction.
We appreciate the opportunity to be of service on this project. If you have any questions regarding this
report or any aspects of the project,please feel free to contact our office.
Sincerely,
E3RA,Inc.
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JIG DETACHED -- 12' �
(2) 700 G
E (896 SF.)
GAL
SEPTIC TANKS
TEST HOLE L❑CATI❑NS `'+' N
TH-1 .
OC LOCATIONS
PIT L❑ TH-1 2`-4 ��1 T AX LANDSCAPIN"
P-1 W 8 ROCKERY/KEYSTONE
8 NEIGHBORING RES. 3-
TIGHTLINE TO
DRY�f EXISTING HOME & DECK
IN E L 15` TO BE REMOVED
EXISTING T ROCKERIES �. S (01
11201 .
PROPOSED REPLACEMENT H(
w E EXISTING WELL 3 BDRM SFR (52'x32')
A'
PROJECT: 9110 E SR-106
Union, Washington
E3RA inc.
NOTE: PO Box 44840 SHEET TITLE: Site and Exploration Plan
BOUNDARY AND TOPOGRAPHY ARE BASED ON 20 0 20 60 Tacoma, WA 98448 DESIGNER: CRL JOB NO.T11055
MAPPING PROVIDED TO E3RA BY CBAY 253-537-9400
AND OBSERVATIONS MADE IN THE FIELD. THE 253-537-9401 fax DRAWN BY: CRL SCALE: 1" = 20
INFORMATION SHOWN DOES NOT CONSTITUTE A FIELD CHECKED BY: JEB FIGURE-2
SURVEY BY E3RA. www.e3ra.com
DATE: May 31, 2011 FILE: T11055.dwg
A 500 A'
160
140
120 _
i
100
80 I I
1
60
40
ADVANCED OUPA ASH
PROPOSED HOUSE 125 pcf, Cohesion = 50, 42°
20
PLIESTOCENE GRAVEL TH-1
f
125 ` cf, Cohesion = 50, 380
0 50 100 150 200 250 300 350 400 780
PROJECT: 9110 E SR-106
E3RA Inc. Union, Washington
PO Box 44840 SHEET TITLE: Geologic Profile
Tacoma, WA 98448 DESIGNER: CRL JOB NO.T11055
253-537-9400 DRAWN BY: CRL SCALE: As Shown
253-537-9401 fax '
WWW.e3ra.com CHECKED BY: JEB FIGURE:3 II
DATE: May 31, 2011 FILE: T11055.dwg
APPENDIX A
LOG OF SOIL TEST HOLE
Test Hole Log— Bubba and Lynn Vandling Tl 1055
Depth (feet) Material Description
Test Pit TH-1
Location: West of planned building
Approximate ground surface elevation: 10 to 15 feet
0.0 — 1.0 Medium Dense to dense,damp to moist,light brown,sandy GRAVEL with
some/trace silt (Pre-Vashon Gravel)(GP-GM).
Test pit terminated at 1 foot
No groundwater encountered
Logged on 5/25/11 by FER
A-1
APPENDIX B
Slope Stability Analysis
Geometry and Boundary Conditions
Problem: T11055 Vandling
850
800
750
700
650
600 3
�M1
550
500
450
400
L=2000
350- 1 2 4
300
0 100 200 300 400 500 600 700 800
(Scale in Feet)
Geometry and Boundary Conditions
Problem: T11055 Vandling Static - FS Min = 1 .526
850
800
750
700
650
600 3
550
500
450
400
L=2000
350 2 4
300
0 160 260 300 400 500 600 700 800
(Scale in Feet)
Geometry and Boundary Conditions
Problem: T11055 Vandling Static - FS Min = 1 .526
850
800
750
A
F
700
650 `r
.� 10.
600 3
550
500
s-
450 �0(1 t
400
L=2000
350
4
300
0 100 200 300 400 500 600 700 800
(Scale in Feet)
result.out
** PCSTABL6 **
by
Purdue university
1
--slope stability Analysis--
simplified janbu, simplified Bishop
or spencers Method of slices
Run Date:
Time of Run:
Run By:
Input Data Filename: run.in
Output Filename: result.out
Unit: ENGLISH
Plotted output Filename: result.put
PROBLEM DESCRIPTION T11055 Vandling Static
BOUNDARY COORDINATES
3 Top Boundaries
4 Total Boundaries
Boundary x-Left Y-Left x-Right Y-Right soil Type
No. (ft) (ft) (ft) (ft) BeloW Bnd
1 0.00 315.00 225.00 316.00 1
2 225.00 316.00 226.00 320.00 2
3 226.00 320.00 780.00 800.00 2
4 225.00 316.00 780.00 316.00 1
1
ISOTROPIC SOIL PARAMETERS
2 Type(s) of Soil
Soil Total Saturated Cohesion Friction Pore Pressure Piez.
Type unit wt. Unit Wt. Intercept Angle Pressure Constant surface
No. (pcf) (pcf) (psf) (deg) Param. (psf) No.
1 125.0 125.0 50.0 38.0 0.00 0.0 0
2 125.0 125.0 50.0 42.0 0.00 0.0 0
1 '
BOUNDARY LOAD(S)
1 Load(s) Specified
Page 1
result.out
Load x-Left x-Right intensity Deflection
No. (ft) (ft) (psf) (deg)
1 160.00 210.00 2000.0 0.0
NOTE - Intensity Is specified AS A uniformly Distributed
Force Acting on A Horizontally Projected surface.
1
A Critical Failure surface searching Method, using A Random
Technique For Generating Circular surfaces, Has Been specified.
400 Trial Surfaces Have Been Generated.
20 surfaces Initiate From Each of 20 Points Equally spaced
Along The Ground Surface Between x = 210.00 ft.
and x = 210.10 ft.
Each Surface Terminates Between x = 350.00 ft.
and x = 780.00 ft.
unless Further Limitations were imposed, The Minimum Elevation
At which A Surface Extends Is Y = 0.00 ft.
20.00 ft. Line Segments Define Each Trial Failure surface.
1
Following Are Displayed The Ten Most Critical Of The Trial
Failure surfaces Examined. They Are ordered - Most critical
First.
* Safety Factors Are Calculated By The Modified Bishop Method
Failure surface specified By 41 Coordinate Points
Point x-Surf Y-Surf
No. (ft) (ft)
1 210.07 315.93
2 230.00 314.28
3 249.98 313.43
4 269.98 313.41
5 289.97 314.20
6 309.90 315.82
7 329.75 318.24
8 349.49 321.47
9 369.08 325. 51
10 388.49 330.35
Page 2
result.out
11 407.68 335.97
12 426.63 342.37
13 445.29 349. 55
14 463.65 357.48
15 481.68 366.15
16 499.33 375.56
17 516.58 385.68
18 533.40 396.49
19 549.77 407.99
20 565.65 420.14
21 581.03 432.93
22 595.86 446.34
23 610.14 460.35
24 623.83 474.93
25 636.92 490.05
26 649.37 505.70
27 661.18 521.84
28 672.32 538.46
29 682.76 555.51
30 692.50 572.98
31 701.52 590.83
32 709.80 609.04
33 717.33 627. 56
34 724.10 646.38
35 730.09 665.47
36 735.30 684.78
37 739.71 704.28
38 743.32 723.95
39 746.13 743.76
40 748.12 763.66
41 748.66 772.85
circle center at x = 260.6 ; Y = 802.4 and Radius, 489.1
��- 1.526
Individual data on the 43 slices
Water water Earthquake
Force Force Force Force Force Surcharge
slice width weight Top Bot Norm Tan Hor ver Load
No. (ft) (lbs) (lbs) (lbs) (lbs) (lbs) (lbs) (lbs) (lbs)
1 14.9 1220.8 0.0 0.0 0.0 0.0 0.0 0.0 0.0
2 1.0 418.7 0.0 0.0 0.0 0.0 0.0 0.0 0.0
3 4.0 3645.4 0.0 0.0 0.0 0.0 0.0 0.0 0.0
4 20.0 45627.4 0.0 0.0 0.0 0.0 0.0 0.0 0.0
5 20.0 90051.4 0.0 0.0 0.0 0.0 0.0 0.0 0.0
6 20.0 132288.4 0.0 0.0 0.0 0.0 0.0 0.0 0.0
7 19.9 172061.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0
8 1.5 14665.1 0.0 0.0 0.0 0.0 0.0 0.0 0.0
9 18.3 194451.9 0.0 0.0 0.0 0.0 0.0 0.0 0.0
10 19.7 243232.1 0.0 0.0 0.0 0.0 0.0 0.0 0.0
11 19.6 274210.7 0.0 0.0 0.0 0.0 0.0 0.0 0.0
12 19.4 301888.2 0.0 0.0 0.0 0.0 0.0 0.0 0.0
13 19.2 326131.1 0.0 0.0 0.0 0.0 0.0 0.0 0.0
14 18.9 346837.5 0.0 0.0 0.0 0.0 0.0 0.0 0.0
15 18.7 363939.1 0.0 0.0 0.0 0.0 0.0 0.0 0.0
16 18.4 377400.3 0.0 0.0 0.0 0.0 0.0 0.0 0.0
Page 3
result.out
17 18.0 387218.5 0.0 0.0 0.0 0.0 0.0 0.0 0.0
18 17.7 393424.8 0.0 0.0 0.0 0.0 0.0 0.0 0.0
19 17.3 396081.5 0.0 0.0 0.0 0.0 0.0 0.0 0.0
20 16.8 395284.9 0.0 0.0 0.0 0.0 0.0 0.0 0.0
21 16.4 391161.6 0.0 0.0 0.0 0.0 0.0 0.0 0.0
22 15.9 383869.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0
23 15.4 373592.8 0.0 0.0 0.0 0.0 0.0 0.0 0.0
24 14.8 360544.8 0.0 0.0 0.0 0.0 0.0 0.0 0.0
25 14.3 344966.3 0.0 0.0 0.0 0.0 0.0 0.0 0.0
26 13.7 327119.7 0.0 0.0 0.0 0.0 0.0 0.0 0.0
27 13.1 307288.7 0.0 0.0 0.0 0.0 0.0 0.0 0.0
28 12.5 285781.5 0.0 0.0 0.0 0.0 0.0 0.0 0.0
29 11.8 262917.2 0.0 0.0 0.0 0.0 0.0 0.0 0.0
30 11.1 239033.4 0.0 0.0 0.0 0.0 0.0 0.0 0.0
31 10.4 214480.3 0.0 0.0 0.0 0.0 0.0 0.0 0.0
32 9.7 189619.1 0.0 0.0 0.0 0.0 0.0 0.0 0.0
33 9.0 164813.1 0.0 0.0 0.0 0.0 0.0 0.0 0.0
34 8.3 140434.6 0.0 0.0 0.0 0.0 0.0 0.0 0.0
35 7.5 116855.2 0.0 0.0 0.0 0.0 0.0 0.0 0.0
36 6.8 94446.2 0.0 0.0 0.0 0.0 0.0 0.0 0.0
37 6.0 73574.1 0.0 0.0 0.0 0.0 0.0 0.0 0.0
38 5.2 54597. 5 0.0 0.0 0.0 0.0 0.0 0.0 0.0
39 4.4 37865.5 0.0 0.0 0.0 0.0 0.0 0.0 0.0
40 3.6 23716.3 0.0 0.0 0.0 0.0 0.0 0.0 0.0
41 2.8 12471.1 0.0 0.0 0.0 0.0 0.0 0.0 0.0
42 2.0 4434.2 0.0 0.0 0.0 0.0 0.0 0.0 0.0
43 0.5 295.2 0.0 0.0 0.0 0.0 0.0 0.0 0.0
Failure surface specified By 40 coordinate Points
Point X-Surf Y-Surf
No. (ft) (ft)
1 210.04 315.93
2 229.97 314.26
3 249.96 313.44
4 269.96 313.47
5 289.94 314.34
6 309.86 316.06
7 329.70 318.63
8 349.41 322.03
9 368.95 326.27
10 388.30 331.33
11 407.42 337.21
12 426.26 343.90
13 444.81 351.38
14 463.03 359.64
15 480.88 368.67
16 498.32 378.44
17 515.34 388.95
18 531.90 400.17
19 547.96 412.08
20 563.51 424.66
21 578.51 437.89
22 592.93 451.75
23 606.75 466.20
24 619.95 481.23
25 632. 50 496.81
26 644.37 512.90
27 655.55 529.48
28 666.02 546. 53
29 675.75 564.00
Page 4
result.out
30 684.74 581.87
31 692.95 600.10
32 700.39 618.67
33 707.03 637. 53
34 712.87 656.66
35 717.89 676.02
36 722.08 695.58
37 725.44 715.29
38 727.96 735.13
39 729.63 755.06
40 729.69 756.41
circle center At X = 259.4 ; Y = 784. 5 and Radius, 471.2
1. 526
1
Failure surface Specified By 35 coordinate Points
Point X-surf Y-surf
No. (ft) (ft)
1 210.02 315.93
2 229.95 314.27
3 249.94 313.58
4 269.93 313.86
5 289.89 315.12
6 309.77 317.35
7 329. 51 320.54
8 349.08 324.69
9 368.42 329.78
10 387.49 335.82
11 406.24 342.77
12 424.63 350.63
13 442.62 359.38
14 460.15 368.99
15 477.21 379.44
16 493.73 390.71
17 509.68 402.77
18 525.03 415.60
19 539.73 429.16
20 553.76 443.41
21 567.07 458.34
22 579.65 473.89
23 591.45 490.04
24 602.45 506.74
25 612.62 523.96
26 621.95 541.65
27 630.40 559.78
28 637.96 578.29
29 644.60 597.16
30 650.33 616.32
31 655.11 635.74
32 658.94 655.37
33 661.81 675.16
34 663.71 695.07
35 663.91 699.42
Page 5
i
Iresult.out
circle center At X = 254.1 ; Y = 724.2 and Radius, 410.6
1.527
Failure surface specified By 36 coordinate Points
IPoint X-surf Y-surf
No. ft ft
C ) C )
1 210.10 315.93
2 230.03 314.26
3 250.02 313. 53
4 270.02 313.76
5 289.98 314.93
6 309.87 317.05
7 329.63 320.11
8 349.23 324.11
9 368.61 329.03
10 387.74 334.87
11 406.57 341.61
12 425.06 349.23
e 13 443.17 357.72
I 14 460.85 367.07
15 478.07 377.24
16 494.79 388.22
I 17 510.97 399.98
18 526.57 412. 50
19 541.56 425.74
20 555.90 439.68
21 569.56 454.28
22 582.52 469. 51
23 594.74 485.35
24 606.19 501.74
25 616.85 518.67
26 626.70 536.07
27 635.71 553.93
28 643.86 572.19
I 29 651.14 590.82
30 657.52 609.78
31 662.99 629.01
32 667.55 648.49
I 33 671.17 668.16
34 673.86 687.98
35 675.61 707.90
36 675.67 709.61
Icircle center At X = 255.3 ; Y = 734.6 and Radius, 421.1
1. 528 �--
1
IFailure surface specified By 32 Coordinate Points
I Page 6
� I
result.out
14 463.88 356.13
15 481.97 364.66
16 499.70 373.91
17 517.04 383.87
18 533.97 394.53
19 550.45 405.86
20 566.46 417.85
21 581.97 430.47
22 596.95 443.72
23 611.39 457.56
24 625.26 471.97
25 638.53 486.93
26 651.18 502.42
27 663.20 518.41
28 674.56 534.87
29 685.25 551.77
30 695.24 569.10
31 704.52 586.81
32 713.08 604.89
33 720.90 623.30
34 727.97 642.01
35 734.28 660.99
36 739.81 680.21
37 744.56 699.63
38 748.52 719.24
39 751.68 738.99
40 754.05 758.85
41 755.60 778.78
42 755.61 778.86
circle center At x = 262.3 ; Y = 807.3 and Radius, 494.1
1.529 �--
1
Failure surface specified By 31 coordinate Points
Point X-Surf Y-Surf
No. (ft) (ft)
1 210.07 315.93
2 230.00 314.25
3 249.99 313.65
4 269.98 314.15
5 289.92 315.75
6 309.74 318.44
7 329.38 322.20
8 348.79 327.04
9 367.90 332.93
10 386.66 339.86
11 405.01 347.81
12 422.90 356.75
13 440.28 366.66
14 457.08 377. 50
15 473.27 389.25
16 488.79 401.86
17 503. 59 415.31
18 517.64 429. 55
Page 8
result.out
19 530.88 444.53
20 543.29 460.22
21 554.82 476.56
22 565.43 493.51
23 575.10 511.02
24 583.80 529.03
25 591.50 547.49
26 598.17 566.34
27 603.81 585.53
28 608.38 605.00
29 611.88 624.69
30 614.30 644. 55
31 615.14 657.16
circle center At x = 250.8 ; Y = 678.7 and Radius, 365.1
��- 1.529
Failure surface specified By 34 coordinate Points
Point x-surf Y-surf
No. (ft) (ft)
1 210.08 315.93
2 230.01 314.24
3 250.00 313. 53
4 270.00 313.81
5 289.96 315.08
6 309.83 317.33
7 329.57 320.56
8 349.12 324.77
9 368.44 329.93
10 387.48 336.05
11 406.20 343.10
12 424.55 351.07
13 442.47 359.93
14 459.94 369.67
15 476.91 380.26
16 493.33 391.67
17 509.17 403.89
18 524.38 416.87
19 538.93 430.59
20 552.79 445.01
21 565.92 460.10
22 578.28 475.82
23 589.86 492.13
24 600.61 509.00
25 610.51 526.37
26 619.55 544.21
27 627.69 562.48
28 634.92 581.13
29 641.21 600.11
30 646.56 619.38
31 650.95 638.90
32 654.38 658.60
33 656.82 678.45
34 657.98 694.28
Page 9
result.out
circle Center At X = 254.4 ; Y = 717.8 and Radius, 404.3
1.529
1
Failure surface specified By 25 Coordinate Points
Point X-Surf Y-Surf
No. (ft) (ft)
1 210.09 315.93
2 230.02 314.28
3 250.02 314.01
4 269.99 315.14
5 289.83 317.65
6 309.45 321. 54
7 328.75 326.78
8 347.64 333.36
9 366.02 341.23
10 383.82 350.35
11 400.94 360.70
12 417.29 372.21
13 432.81 384.83
14 447.41 398. 50
15 461.02 413.15
16 473.58 428.71
17 485.03 445.11
18 495.31 462.27
19 504.38 480.10
20 512.18 498. 51
21 518.68 517.43
22 523.85 536.75
23 527.66 556.38
24 530.10 576.23
25 530.50 583.83
circle center At X = 243.8 ; Y = 601.3 and Radius, 287.4
1.530
Failure surface specified By 30 Coordinate Points
Point X-surf Y-surf
No. (ft) (ft)
1 210.01 315.93
2 229.93 314.22
3 249.92 313.64
4 269.92 314.19
5 289.85 315.86
6 309.65 318.65
7 329.27 322.56
8 348.63 327.56
Page 10
result.out
9 367.68 333.65
10 386.36 340.80
11 404.60 349.00
12 422.36 358.21
13 439.56 368.40
14 456.16 379.55
15 472.11 391.62
16 487.36 404. 57
17 501.84 418.36
18 515.53 432.94
19 528.38 448.27
20 540.33 464.30
21 551.37 480.98
22 561.45 498.26
23 570.54 516.07
24 578.61 534.37
25 585.63 553.10
26 591.59 572.19
27 596.46 591. 59
28 600.23 611.23
29 602.89 631.05
30 604.17 647.65
Circle Center At X = 250.3 ; Y = 668.1 and Radius, 354.5
1.530
1
Y A X I S F T
0.00 176.00 352.00 528.00 704.00 880.00
x0.00 +---------+------- +---------+---------+---------+
176.00 +
- 11/
- 1
- 19. .
A 352.00 + 15. . . . . .
- 119. . . . . .
- .139. . . . .
- 11599. . . . .
- .11399. . .
12359999.
x 528.00 + .11350. .99.99.
- .1133550. . . . . .
- .612335557000. .
- . .11.3333555575
- . .1124.33333.8
- .61112. .44333.
I 704.00 + . .6111122. . . .
. .661111112.
Page 11
result.out
- . . . . .6611.
s 880.00 +
1056.00 +
F 1232.00 +
T 1408.00 +
Page 12
Geometry and Boundary Conditions
Problem: T11055 Vandling Seismic - FS Min = 1 .206
850
800
750
700
650
600 3
550
500
450
400
L=2000
350 _ 1 2 4
300
r
0 100 200 360 400 560 660 700 800
(Scale in Feet)
Geometry and Boundary Conditions
Problem: T11055 Vandling Seismic - FS Min = 1 .206
850
800
750 i
700
650 4 r
600 3
550 (( f ,
500 '^
1
450 '%'
400
L=2000
350 1 2 4
Aft
300
0 100 260 300 400 500 600 700 800
(Scale in Feet)
result.out
*� PCSTABL6
by
Purdue University
1
--slope stability Analysis--
Simplified janbu, simplified Bishop
or spencers Method of slices
Run Date:
Time of Run:
Run By:
Input Data Filename: run.in
Output Filename: result.out
Unit: ENGLISH
Plotted output Filename: result.plt
PROBLEM DESCRIPTION T11055 Vandling Seismic
BOUNDARY COORDINATES
3 Top Boundaries
4 Total Boundaries
Boundary x-Left Y-Left x-Right Y-Right Soil Type
No. (ft) (ft) (ft) (ft) BeloW Bnd
1 0.00 315.00 225.00 316.00 1
2 225.00 316.00 226.00 320.00 2
3 226.00 320.00 780.00 800.00 2
4 225.00 316.00 780.00 316.00 1
1
ISOTROPIC SOIL PARAMETERS
2 Type(s) of soil
Soil Total saturated Cohesion Friction Pore Pressure Piez.
Type Unit Wt. Unit Wt. Intercept Angle Pressure Constant Surface
No. (pcf) (pcf) (psf) (deg) Param. (psf) No.
1 125.0 125.0 50.0 38.0 0.00 0.0 0
2 125.0 125.0 50.0 42.0 0.00 0.0 0
1
BOUNDARY LOAD(S)
1 Load(s) Specified
Page 1
result.out
Load x-Left x-Right Intensity Deflection
No. (ft) (ft) (psf) (deg)
1 160.00 210.00 2000.0 0.0
NOTE - Intensity Is Specified As A uniformly Distributed
Force Acting on A Horizontally Projected Surface.
A Horizontal Earthquake Loading Coefficient
OfO.150 Has Been Assigned
A vertical Earthquake Loading Coefficient
OfO.000 Has Been Assigned
Cavitation Pressure = 0.0 (psf)
1
A Critical Failure surface searching Method, using A Random
Technique For Generating Circular surfaces, Has Been specified.
400 Trial surfaces Have Been Generated.
20 surfaces Initiate From Each of 20 Points Equally spaced
Along The Ground surface Between x = 210.00 ft.
and x = 210.10 ft.
Each surface Terminates Between x = 350.00 ft.
and x = 780.00 ft.
unless Further Limitations were Imposed, The Minimum Elevation
At which A surface Extends Is Y = 0.00 ft.
20.00 ft. Line Segments Define Each Trial Failure surface.
1
Following Are Displayed The Ten Most Critical of The Trial
Failure surfaces Examined. They Are ordered - Most Critical
First.
* * safety Factors Are Calculated By The Modified Bishop Method
Failure surface Specified By 41 Coordinate Points
Point x-Surf Y-Surf
No. (ft) (ft)
Page 2
result.out
1 210.07 315.93
2 230.00 314.28
3 249.98 313.43
4 269.98 313.41
5 289.97 314.20
6 309.90 315.82
7 329.75 318.24
8 349.49 321.47
9 369.08 325.51
10 388.49 330.35
11 407.68 335.97
12 426.63 342.37
13 445.29 349.55
14 463.65 357.48
15 481.68 366.15
16 499.33 375.56
17 516.58 385.68
18 533.40 396.49
19 549.77 407.99
20 565.65 420.14
21 581.03 432.93
22 595.86 446.34
23 610.14 460.35
24 623.83 474.93
25 636.92 490.05
26 649.37 505.70
27 661.18 521.84
28 672.32 538.46
29 682.76 555.51
30 692.50 572.98
31 701.52 590.83
32 709.80 609.04
33 717.33 627. 56
34 724.10 646.38
35 730.09 665.47
36 735.30 684.78
37 739.71 704.28
38 743.32 723.95
39 746.13 743.76
40 748.12 763.66
41 748.66 772.85
circle center At x = 260.6 ; Y = 802.4 and Radius, 489.1
��- 1.206
Individual data on the 43 slices
water water Earthquake
Force Force Force Force Force Surcharge
slice width weight Top Bot Norm Tan Hor ver Load
No. (ft) (lbs) (lbs) (lbs) (lbs) (lbs) (lbs) (lbs) (lbs)
1 14.9 1220.8 0.0 0.0 0.0 0.0 183.1 0.0 0.0
2 1.0 418.7 0.0 0.0 0.0 0.0 62.8 0.0 0.0
3 4.0 3645.4 0.0 0.0 0.0 0.0 546.8 0.0 0.0
4 20.0 45627.4 0.0 0.0 0.0 0.0 6844.1 0.0 0.0
5 20.0 90051.4 0.0 0.0 0.0 0.0 13507.7 0.0 0.0
6 20.0 132288.4 0.0 0.0 0.0 0.0 19843.3 0.0 0.0
Page 3
result.out
7 19.9 172061.0 0.0 0.0 0.0 0.0 25809.2 0.0 0.0
8 1.5 14665.1 0.0 0.0 0.0 0.0 2199.8 0.0 0.0
9 18.3 194451.9 0.0 0.0 0.0 0.0 29167.8 0.0 0.0
10 19.7 243232.1 0.0 0.0 0.0 0.0 36484.8 0.0 0.0
11 19.6 274210.7 0.0 0.0 0.0 0.0 41131.6 0.0 0.0
12 19.4 301888.2 0.0 0.0 0.0 0.0 45283.2 0.0 0.0
13 19.2 326131.1 0.0 0.0 0.0 0.0 48919.7 0.0 0.0
14 18.9 346837.5 0.0 0.0 0.0 0.0 52025.6 0.0 0.0
15 18.7 363939.1 0.0 0.0 0.0 0.0 54590.9 0.0 0.0
16 18.4 377400.3 0.0 0.0 0.0 0.0 56610.0 0.0 0.0
17 18.0 387218. 5 0.0 0.0 0.0 0.0 58082.8 0.0 0.0
18 17.7 393424.8 0.0 0.0 0.0 0.0 59013.7 0.0 0.0
19 17.3 396081.5 0.0 0.0 0.0 0.0 59412.2 0.0 0.0
20 16.8 395284.9 0.0 0.0 0.0 0.0 59292.7 0.0 0.0
21 16.4 391161.6 0.0 0.0 0.0 0.0 58674.2 0.0 0.0
22 15.9 383869.0 0.0 0.0 0.0 0.0 57580.4 0.0 0.0
23 15.4 373592.8 0.0 0.0 0.0 0.0 56038.9 0.0 0.0
24 14.8 360544.8 0.0 0.0 0.0 0.0 54081.7 0.0 0.0
25 14.3 344966.3 0.0 0.0 0.0 0.0 51744.9 0.0 0.0
26 13.7 327119.7 0.0 0.0 0.0 0.0 49068.0 0.0 0.0
27 13.1 307288.7 0.0 0.0 0.0 0.0 46093.3 0.0 0.0
28 12.5 285781. 5 0.0 0.0 0.0 0.0 42867.2 0.0 0.0
29 11.8 262917.2 0.0 0.0 0.0 0.0 39437.6 0.0 0.0
30 11.1 239033.4 0.0 0.0 0.0 0.0 35855.0 0.0 0.0
31 10.4 214480.3 0.0 0.0 0.0 0.0 32172.1 0.0 0.0
32 9.7 189619.1 0.0 0.0 0.0 0.0 28442.9 0.0 0.0
33 9.0 164813.1 0.0 0.0 0.0 0.0 24722.0 0.0 0.0
34 8.3 140434.6 0.0 0.0 0.0 0.0 21065.2 0.0 0.0
35 7.5 116855.2 0.0 0.0 0.0 0.0 17528.3 0.0 0.0
36 6.8 94446.2 0.0 0.0 0.0 0.0 14166.9 0.0 0.0
37 6.0 73574.1 0.0 0.0 0.0 0.0 11036.1 0.0 0.0
38 5.2 54597. 5 0.0 0.0 0.0 0.0 8189.6 0.0 0.0
39 4.4 37865.5 0.0 0.0 0.0 0.0 5679.8 0.0 0.0
40 3.6 23716.3 0.0 0.0 0.0 0.0 3557.4 0.0 0.0
41 2.8 12471.1 0.0 0.0 0.0 0.0 1870.7 0.0 0.0
42 2.0 4434.2 0.0 0.0 0.0 0.0 665.1 0.0 0.0
43 0.5 295.2 0.0 0.0 0.0 0.0 44.3 0.0 0.0
Failure surface specified By 40 Coordinate Points
Point x-surf Y-surf
No. (ft) (ft)
1 210.04 315.93
2 229.97 314.26
3 249.96 313.44
4 269.96 313.47
5 289.94 314.34
6 309.86 316.06
7 329.70 318.63
8 349.41 322.03
9 368.95 326.27
10 388.30 331.33
11 407.42 337.21
12 426.26 343.90
13 444.81 351.38
14 463.03 359.64
15 480.88 368.67
16 498.32 378.44
17 515.34 388.95
18 531.90 400.17
19 547.96 412.08
Page 4
result.out
20 563.51 424.66
21 578.51 437.89
22 592.93 451.75
23 606.75 466.20
24 619.95 481.23
25 632.50 496.81
26 644.37 512.90
27 655. 55 529.48
28 666.02 546.53
29 675.75 564.00
30 684.74 581.87
31 692.95 600.10
32 700.39 618.67
33 707.03 637.53
34 712.87 656.66
35 717.89 676.02
36 722.08 695. 58
37 725.44 715.29
38 727.96 735.13
39 729.63 755.06
40 729.69 756.41
circle center At x = 259.4 ; Y = 784.5 and Radius, 471.2
��- 1.206
1
Failure surface specified By 35 coordinate Points
Point x-surf Y-surf
No. (ft) (ft)
1 210.02 315.93
2 229.95 314.27
3 249.94 313.58
4 269.93 313.86
5 289.89 315.12
6 309.77 317.35
7 329.51 320.54
8 349.08 324.69
9 368.42 329.78
10 387.49 335.82
11 406.24 342.77
12 424.63 350.63
13 442.62 359.38
14 460.15 368.99
15 477.21 379.44
16 493.73 390.71
17 509.68 402.77
18 525.03 415.60
19 539.73 429.16
20 553.76 443.41
21 567.07 458.34
22 579.65 473.89
23 591.45 490.04
24 602.45 506.74
25 612.62 523.96
26 621.95 541.65
Page 5
result.out
27 630.40 559.78
28 637.96 578.29
29 644.60 597.16
30 650.33 616.32
31 655.11 635.74
32 658.94 655.37
33 661.81 675.16
34 663.71 695.07
35 663.91 699.42
Circle Center At X = 254.1 ; Y = 724.2 and Radius, 410.6
-�- 1.207 **_
Failure surface specified By 36 Coordinate Points
Point X-surf Y-surf
No. (ft) (ft)
1 210.10 315.93
2 230.03 314.26
3 250.02 313.53
4 270.02 313.76
5 289.98 314.93
6 309.87 317.05
7 329.63 320.11
8 349.23 324.11
9 368.61 329.03
10 387.74 334.87
11 406.57 341.61
12 425.06 349.23
13 443.17 357.72
14 460.85 367.07
15 478.07 377.24
16 494.79 388.22
17 510.97 399.98
18 526.57 412. 50
19 541. 56 425.74
20 555.90 439.68
21 569. 56 454.28
22 582.52 469.51
23 594.74 485.35
24 606.19 501.74
25 616.85 518.67
26 626.70 536.07
27 635.71 553.93
28 643.86 572.19
29 651.14 590.82
30 657. 52 609.78
31 662.99 629.01
32 667. 55 648.49
33 671.17 668.16
34 673.86 687.98
35 675.61 707.90
36 675.67 709.61
Circle Center At X = 255.3 ; Y = 734.6 and Radius, 421.1
Page 6
result.out
1.208
1
Failure surface specified By 32 coordinate Points
Point X-Surf Y-Surf
No. (ft) (ft)
1 210.01 315.93
2 229.94 314.26
3 249.93 313.66
4 269.93 314.14
5 289.87 315.70
6 309.69 318.33
7 329.35 322.02
8 348.78 326.77
9 367.92 332. 56
10 386.72 339.37
11 405.13 347.18
12 423.10 355.98
13 440.56 365.73
14 457.47 376.41
15 473.78 387.99
16 489.44 400.42
17 504.41 413.69
18 518.64 427.74
19 532.10 442.53
20 544.74 458.04
21 556.52 474.20
22 567.41 490.97
23 577.39 508.30
24 586.42 526.15
25 594.47 544.46
26 601. 52 563.17
27 607.56 582.24
28 612. 56 601.60
29 616.50 621.21
30 619.39 641.00
31 621.20 660.92
32 621.26 662.46
circle center At X = 251.1 ; Y = 684. 5 and Radius, 370.9
�-- 1.208 **_
Failure surface Specified By 42 coordinate Points
Point X-Surf Y-Surf
No. (ft) (ft)
1 210.01 315.93
2 229.94 314.22
3 249.92 313.31
Page 7
result.out
4 269.92 313.21
5 289.90 313.93
6 309.85 315.45
7 329.71 317.77
8 349.46 320.90
9 369.08 324.83
10 388. 51 329.54
11 407.74 335.04
12 426.73 341.31
13 445.45 348.35
14 463.88 356.13
15 481.97 364.66
16 499.70 373.91
17 517.04 383.87
18 533.97 394.53
19 550.45 405.86
20 566.46 417.85
21 581.97 430.47
22 596.95 443.72
23 611.39 457.56
24 625.26 471.97
25 638. 53 486.93
26 651.18 502.42
27 663.20 518.41
28 674. 56 534.87
29 685.25 551.77
30 695.24 569.10
31 704. 52 586.81
32 713.08 604.89
33 720.90 623.30
34 727.97 642.01
35 734.28 660.99
36 739.81 680.21
37 744.56 699.63
38 748.52 719.24
39 751.68 738.99
40 754.05 758.85
41 755.60 778.78
42 755.61 778.86
circle center At x = 262.3 ; Y = 807.3 and Radius, 494.1
1.208
1
Failure surface specified By 31 coordinate Points
Point x-surf Y-surf
No. (ft) (ft)
1 210.07 315.93
2 230.00 314.25
3 249.99 313.65
4 269.98 314.15
5 289.92 315.75
6 309.74 318.44
7 329.38 322.20
8 348.79 327.04
Page 8
result.out
9 367.90 332.93
10 386.66 339.86
11 405.01 347.81
12 422.90 356.75
13 440.28 366.66
14 457.08 377. 50
15 473.27 389.25
16 488.79 401.86
17 503. 59 415.31
18 517.64 429.55
19 530.88 444.53
20 543.29 460.22
21 554.82 476. 56
22 565.43 493. 51
23 575.10 511.02
24 583.80 529.03
25 591.50 547.49
26 598.17 566.34
27 603.81 585.53
28 608.38 605.00
29 611.88 624.69
30 614.30 644.55
31 615.14 657.16
Circle Center At x = 250.8 ; Y = 678.7 and Radius, 365.1
1.209
Failure surface specified By 34 coordinate Points
Point x-surf Y-Surf
No. (ft) (ft)
1 210.08 315.93
2 230.01 314.24
3 250.00 313.53
4 270.00 313.81
5 289.96 315.08
6 309.83 317.33
7 329. 57 320.56
8 349.12 324.77
9 368.44 329.93
10 387.48 336.05
11 406.20 343.10
12 424.55 351.07
13 442.47 359.93
14 459.94 369.67
15 476.91 380.26
16 493.33 391.67
17 509.17 403.89
18 524.38 416.87
19 538.93 430.59
20 552.79 445.01
21 565.92 460.10
22 578.28 475.82
23 589.86 492.13
24 600.61 509.00
25 610.51 526.37
Page 9
result.out
26 619. 55 544.21
27 627.69 562.48
28 634.92 581.13
29 641.21 600.11
30 646. 56 619.38
31 650.95 638.90
32 654.38 658.60
33 656.82 678.45
34 657.98 694.28
Circle Center At X = 254.4 ; Y = 717.8 and Radius, 404.3
1.209
1
Failure surface specified By 25 Coordinate Points
Point X-surf Y-surf
No. (ft) (ft)
1 210.09 315.93
2 230.02 314.28
3 250.02 314.01
4 269.99 315.14
5 289.83 317.65
6 309.45 321.54
7 328.75 326.78
8 347.64 333.36
9 366.02 341.23
10 383.82 350.35
11 400.94 360.70
12 417.29 372.21
13 432.81 384.83
14 447.41 398.50
15 461.02 413.15
16 473.58 428.71
17 485.03 445.11
18 495.31 462.27
19 504.38 480.10
20 512.18 498.51
21 518.68 517.43
22 523.85 536.75
23 527.66 556.38
24 530.10 576.23
25 530.50 583.83
Circle Center At X = 243.8 ; Y = 601.3 and Radius, 287.4
=* 1.209 **_
Failure surface specified By 30 Coordinate Points
Point X-Surf Y-surf
Page 10
result.out
No. (ft) (ft)
1 210.01 315.93
2 229.93 314.22
3 249.92 313.64
4 269.92 314.19
5 289.85 315.86
6 309.65 318.65
7 329.27 322. 56
8 348.63 327.56
9 367.68 333.65
10 386.36 340.80
11 404.60 349.00
12 422.36 358.21
13 439.56 368.40
14 456.16 379.55
15 472.11 391.62
16 487.36 404.57
17 501.84 418.36
18 515.53 432.94
19 528.38 448.27
20 540.33 464.30
21 551.37 480.98
22 561.45 498.26
23 570.54 516.07
24 578.61 534.37
25 585.63 553.10
26 591.59 572.19
27 596.46 591. 59
28 600.23 611.23
29 602.89 631.05
30 604.17 647.65
circle center At x = 250.3 ; Y = 668.1 and Radius, 354.5
1.210
1
Y A x I S F T
0.00 176.00 352.00 528.00 704.00 880.00
x 0.00 +---------+------- +---------+---------+---------+
176.00 +
- 11/
- 1
- 19. .
A 352.00 + 15. . . . . .
- 119. . . . . .
- .139. . . . .
11599. . . . . .
Page 11
result.out
.11399. . . . . . .
- 12359999.
X 528.00 + .11350. .99.99.
- .1133550. . . . . .
- .612335557000. .
- . .11.3333555575
- . .1124.33333.8
- .61112. .44333.
I 704.00 + . .6111122. . . .
- . .661111112.
. . . . .6611.
S 880.00 +
1056.00 +
F 1232.00 +
T 1408.00 +
Page 12
TO BE KEPT IN "F HE
EIV T
` CouhtO*artment of Community Development ED
��121
Submittal Checklist For a Geotechnical Report 2011
426 W. ('Fn
Instructions: AjR
ST=
This checklist must be submitted with a Geotechnical Report and completed, signed, and stamped by the
licensed professional(s)who prepared the Geotechnical Report for review by Mason County pursuant to
the Mason County Resource Ordinance. If an item found to be not applicable, the report should explain
the basis for the conclusion.
Applicant/Owner: Bubba and Lynn Vandling Parcel#322353190040
Site Address: 9110 East SR 106,Union,Washington
(1) (a)A discussion of general geologic conditions in the vicinity of the proposed development,
Located on page(s)3,4
A discussion of specific soil types
Located on page(s) 5
(b) A discussion of ground water conditions
Located on page(s) 5, 7
(c) A discussion of the upslope geomorphology
Located on page(s) 3, 4
(d) A discussion of the location of upland waterbodies and wetlands
Located on page(s)4
(e) A discussion of history of landslide activity in the activity in the vicinity, as available in the
referenced maps and records
Located on page(s) 4
(2) A site plan which identifies the important development and geologic features.
Located on Map(s) Fig. 2
(3) Locations and logs of exploratory holes or probes.
Located on Map(s) Fig. 2, Appendix A
(4) The area of the proposed development, the boundaries of the hazard, and associated buffers and
setbacks shall be delineated (top, both sides, and toe)on a geologic map of the site.
Located on Map(s) Fig. 2
(5) A minimum of one cross section at a scale which adequately depicts the subsurface profile, and
which incorporates the details of proposed grade changes.
Located on Map(s) Fig. 3
(6) A description and results of slope stability analyses performed for both static and seismic loading
conditions. Analysis should examine worst case failures.The analysis should include the
Simplified Bishop's Method of Circles. The minimum static safety factor is 1.5, the minimum
seismic safety factor is 1.1. and the quasi-static analysis coefficients should be a value of 0.15.
Located on page(s) 5, 6, Appendix B
(7) (a)Appropriate restrictions on placement of drainage features
Located on page(s) 7
(b) Appropriate restrictions on placement of septic drain fields
Located on page(s) N/A
(c) Appropriate restrictions on placement of compacted fills and footings
Located on page(s) 7, 8, 9
Page 1 of 2 Form Effective June 2008
Disclaimer: Mason County does not certify the quality of the work done in this Geotechnical Report.
(d) Recommended buffers from the landslide hazard areas shoreline bluffs and the tops of other
slopes on the property.
Located on page(s) 7
(e) Recommended setbacks from the landslide hazard areas shoreline bluffs and the tops of
other slopes on the property.
Located on page(s)7
(8) Recommendations for the preparation of a detailed clearing and grading plan which specifically
identifies vegetation to be removed, a schedule for vegetation removal and replanting, and the
method of vegetation removal.
Located on page(s)7
(9) Recommendations for the preparation of a detailed temporary erosion control plan which
identifies the specific mitigating measures to be implemented during construction to protect the
slope from erosion, landslides and harmful construction methods.
Located on page(s)7, 8
(10) An analysis of both on-site and off-site impacts of the proposed development.
Located on page(s)7
(11) Specifications of final development conditions such as, vegetative management, drainage,
erosion control, and buffer widths.
Located on page(s)6, 7, 8
(12) Recommendations for the preparation of structural mitigation or details of other proposed
mitigation.
Located on page(s) 7, 8, 9, 10
(13) A site map drawn to scale showing the property boundaries, scale, north arrow, and the location
and nature of existing and proposed development on the site.
Located on Map(s) Fig. 2
/rIV"6fl,�410 hereby certify under penalty of
perjury that I am a civil engineer ticensed in the State of Washingfon with specialized knowledge of
geotechnical/geological engineering or a geologist or engineering geologist licensed in the State of
Washington with special knowledge of the local conditions. I also certify that the Geotechnical
Report, dated , and entitled Geotechnical Report Parcel#322353190040 meets all the
requirements of-We e ason County Resource Ordinance, Landslide Hazard Section, is complete and true,
that the assessment demonstrates conclusively that the risks posed by the landslide hazard can be
mitigated through the included geotechnical design recommendations, and that all hazards are mitigated
in such a manner as to prevent harm to property and public health and safety. (Signature and Stamp)
�e O� YV a s
E in ^ng Se
71 O
1 Sed Geo�
Fred Ernest Renneba m
Page 2 of 2 Form Effective June 2008
Disclaimer: Mason County does not certify the quality of the work done in this Geotechnical Report.