HomeMy WebLinkAboutGEO BLD2011-00037 - BLD Engineering / Geo-tech Reports - 1/18/2011 &U7,9041-0003 7
RECEDED
,'�:N 8 2011
MASON COUNTY,
GEOTECHNICAL REPORT
EVANS PROPERTY
SHELTON, WASHINGTON
PREPARED FOR
BRIAN EvANs
BY
ALL AMERICAN GEOTECHNICAL, INC.
OLYMPIA, WASHINGTON
OCTOBER 18, 2010
ALL AMERicAN GEOTECHNICAL, INC,
CONTACT INFORMATION
PREPARER INFORMATION
GTL PROJECT NUMBER: AAG 10-016
CONTACT: CURTIS D. CUSHMAN
ADDRESS: 8947 BUTTONWOOD LANE NE
OLYMPIA,WASHINGTON 98516
CELL: (360) 754-4612
FACSIMILE: (360)754-4848
EMAIL ADDRESS: CURTIS.CUSHMAN(ii,)COMCAST.NET
CLIENT INFORMATION
CLIENT: BRIAN EVANS
TELEPHONE: (503) 880-6512
E MAIL: BEVANS@PCCSTRUCTURALS.COM
BILLING ADDRESS: BRIAN EVANS
1221 9TH STREET
WEST LINE,OREGON 97068
SITE ADDRESS: 170 E ASH LANE
SHELTON,WASHINGTON 98584
121307500030
GPS LOCATION: N47 17' 08.89" W 122° 51' 39.64"
AAG10-016 8947 Buttonwood Lane NE,Olympia,WA 98516 2
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ALL AMERICAN GEOTECIINICALI, INC.
SCOPE OF UNDERSTANDING
BRUN EVANS
1221 9TH STREET
WEST LINNE,OREGON 97068
RE: GEOTECHNICAL REPORT
PROJECT: EVANS PROPERTY
170 E ASH LANE
SHELTON,WA
PARCEL#: 121307500030
10-18-2010
Dear Brian Evans:
As per your request, we have conducted a soils exploration, foundation evaluation, and slope stability analysis for
the above-mentioned parcel. The results of this investigation,together with our recommendations,are to be found
in the following report. We have provided three copies for your review and distribution.
A representative soil sample was previously taken on the site of the current residence in 1999 and the results will
be reused for this report. The overall view indm&there is
an ini1ppineabiv,,mat under much of the prope �.
The projected porch can be built,and a stair to the beach can be designed and is recommended.
sociate a fu t at can meet- our mg, testing (compaction,
asp'Q.halt, con e , and i pection needs. We appreciate this opportunity to be of service to you and we look
forward to working with you in the future. If you have any questions concerning the above items,the procedures
used,or if we can be of any further assistance please call us at the phone number listed below.
Respectfully Submitted,
GEOTECHNICAL TESTING LABORATORY
moo{
Vijay Chaudhary,E.I.T
Staff Engineer
T
E n Geologist
2439 //ems
Curtis D.Cushman,L.G.,L.E.G.
Senior Engineering Geologist
AAG10-016 8947 Buttonwood Lane NE,Olympia, WA 98516 3
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ALL AMERICAN GEOTECHNICALv INC.
TABLE OF CONTENTS
CONTACT INFORMATION 2
SCOPE OF UNDERSTANDING 3
INTRODUCTION 6
SITE CONDITIONS 8
SURFACE CONDITIONS 8
GEOLOGICALLY HAZARDOUS AREAS 9
LANDSLIDE HAZARD CLASSIFICATION 9
SEISMIC HAZARD CLASSIFICATION 10
EROSION HAZARD CLASSIFICATION 11
SITE SOILS 11
SITE GEOLOGY 12
SUBSURFACE EXPLORATIONS 13
SUBSURFACE CONDITIONS 13
SLOPE STABILITY AND ANALYSIS 14
SLOPE MODELS 16
RECOMMENDATIONS FOR BUILDING SETBACK 18
VEGETATIVE MANAGEMENT 18
RECOMMENDATIONS FOR EROSION CONTROL 19
SEPTIC IMPACT 20
RECOMMENDATIONS FOR SITE DRAINAGE 20
EARTHWORK 21
RECOMMENDATIONS FOR SITE PREPARATION 21
RECOMMENDATIONS FOR STRUCTURAL FILL 21
RECOMMENDATIONS FOR SUITABILITY OF ONSITE SOILS AS FILL 21
RECOMMENDATIONS FOR CUT AND FILL SLOPES 22
RECOMMENDATIONS FOR FOUNDATION SUPPORT 22
SEISMIC LIQUEFACTION HAZARD 23
GEOSEISMIC SETTING 23
LATERAL EARTH PRESSURES 23
RECOMMENDATIONS FOR FLOOR SLAB SUPPORT 24
RECOMMENDATIONS FOR RETAINING WALLS 24
RECOMMENDATIONS FOR RETAINING WALL ALTERNATIVES 24
CONCLUSIONS AND RECOMMENDATIONS 24
GENERAL 24
REPORT LIMITATIONS AND GUIDELINES FOR USE 26
CONTRACTORS ARE RESPONSIBLE FOR SITE SAFETY ON THEIR OWN CONSTRUCTION PROJECTS 26
READ THESE PROVISIONS CLOSELY 26
REFERENCES 27
APPENDIX 29
WELL LOG 30
VICINITY MAP 31
FiGuRE 2 SrrF PLAN Attached
AAG10-016 8947 Buttonwood Lane NE,Olympia,WA 98516 4
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ALL AMMUCAN G EO TECHNICALv INC,
FIGURE 3 EROSION CONTROL NOTES Attached
FIGURE 4 CRoss-SECTION Attached
AAG10-016 8947 Buttonwood Lane NE,Olympia,WA 98516 5
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ALL AMERICAN CEOTECIINICA LI, INC.
INTRODUCTION
This report summarizes the results of our geotechnical consulting services for the single family residence and
surrounding grounds built on the parcel herein described. The site is located above a bluff along a southeast-facing
hillside overlooking Case Inlet on Puget Sound in Mason County. The site is approximately 6.1 miles southeast of
Shelton, Washington. The location of the site is shown relative to the surrounding area on the Vicinity Map,
Figure 1
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Mason County GIS
Our understanding of the project is based on our discussions with the client. In general, a project for water flow
control may be needed to protect the property from erosional damage. French drains and some re-grading may be
required. In addition, some excavation would be required for a contemplated stairway to the shore, and possibly
for a proposed roof on a pre-existing porch. The approximate layout of the site is shown on the Site Plan,Figure 2.
The purpose of our services is to evaluate the surface and subsurface conditions at the site in order to satisfy the
requirements of the Mason County Critical Areas Ordinance, and as a basis for providing geotechnical
recommendations and design criteria for the project. Geotechnical Testing Laboratory is therefore providing
geologic and hydrogeologic services for the project. Specifically,our scope of services for this project includes the
following:
1. A review of the available geologic,hydrogeological and geotechnical data for the site area.
2. A geologic reconnaissance of the site area and surrounding vicinity.
3. Investigation and identification of shallow subsurface conditions at the site by characterizing the
exposed soil,reviewing published well logs,and sampling.
4. Comparison of site to published geologic maps, previous field investigations, and open file
reports. Inspection of aerial photographs to determine the geomorphology of the site.
5. Laboratory grain size for the soil samples collected from the site.
6. Evaluation of the landslide,erosion,and seismic hazards at the site per the Mason County Critical
Areas Ordinance regulations(as of January 1,2007).
7. Building setbacks determined from static and dynamic slope stability modeling.
AAG10-616 8947 Buttonwood Lane NE,Olympia,WA 98516 6
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8. Geotechnical recommendations for site grading including site preparation, subgrade preparation,
fill placement criteria (including hillside grading), temporary and permanent cut and fill slopes,
drainage,and typical erosion control measures(Figure 3).
The bluff on the southeast side of the property exceeds a slope of 40% and is greater in height than 10 feet.
Therefore, Mason County requires that a geotechnical report be prepared in accordance with the Critical Areas
Ordinance.
17.01.100E5 (1) -- A discussion of general geologic conditions, specific soil types, ground
water conditions, the upslope geomorphology and location of upland waterbodies and
wetlands, and history of landslide activity in the vicinity.
AAG10-016 8947 Buttonwood Lane NE,Olympia, WA 98516 7
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SITE CONDITIONS
SURFACE CONDITIONS
The current building is a single-family residence located in an area of sparse residential development in the Puget
Sound glacial upland along the western shore of Case Inlet. The site has a southeastern and eastern exposure. The
5-acre property is an elongated triangle with its apex to the west. Site elevations range from sea level up the 65-
foot high bluff to a flat which then rises gently to 120 feet in final elevation at the west end of the property. The
terrain rises to the west to a flat knoll under 150 feet high about 800 feet away and then slopes off in all directions.
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LOOKING SOUTHEAST
Curtis D Cushman conducted a site reconnaissance on October 1, 2010 and met with Mr. Evans and others. The
purpose of a site visit is to physically observe the property and adjacent properties in order to identify any
recognized geologic conditions. Photographs and visual observations were documented. Site-specific features
were noted. Samples were previously taken at the house location.
The western 3/4ths of the property is densely vegetated with secondary growth trees and vegetation common to the
Northwest. The residence is located on a platform generally sloping east and southeast. Here, there is a sparse
scattering of trees and a blanket of bark. Different varieties of mainly juvenile trees and other vegetation cover the
bluff. There are mature conifers along the edge of the bluff. At the time of the site visits,we observed no evidence
of active surface erosion. No evidence of deep-seated slope instability was observed onsite. Trees are
predominantly straight and vertical except at the bluff,where creep was obvious and one juvenile conifer appeared
to have toppled recently to a"leaner"position.
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Surface water flow was not observed onsite. The general topography of the site area indicates that drainage flows
toward the east and southeast. Some backflow may occur above the house, where there is a series of ponds tied
into culverts and other drains. There are no upland water bodies of note. The nearest wetlands are two small,
isolated ones, each over 1500 feet away.
17.01.100E5 (2) -- A site plan which identifies the important development and geologic
features.
A site plan is attached as Figure 2 at the end of this report.
17.01.1O0E5 (3) -- Locations and logs of exploratory holes or probes.
The location of the 1999 hole is beneath the current house.
17.01.1O0E5 (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.
The area of the present development, boundaries of the landslide hazard area, and associated buffers and setbacks
are demarcated on Figure 2 Site Plan at the end of this report. Appropriate geology is labeled on Figure 2 Site
Plan.
17.01.1O0E5 (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.
A cross-section is attached to this report as Figure 4 Cross-section. The cut and fill that may occur after the
writing of this report will only marginally affect the cross section.
GEOLOGICALLY HAZARDOUS AREAS
LANDSLIDE HAZARD CLASSIFICATION
The Mason County Critical Areas Ordinance(17.01.100A])defines a landslide hazard area as:
The following shall be classified as Landslide Hazard Areas:
a. Areas with any indications of earth movement such as debris slides, earthflows, slumps and rockfalls (see
figure F 100).
b.Areas with artificial oversteepened or unengineered slopes, i.e. cuts or fills.
c. Areas with slopes containing soft or potentially liquefiable soils.
d. Areas oversteepened or otherwise unstable as a result of stream incision, stream bank erosion, and
undercutting by wave action.
e. Slopes greater than 15%(8.5 degrees) and having the following:
i. Hillsides intersecting geologic contacts with a relatively permeable sediment overlying a relatively
impermeable sediment or bedrock(e.g. sand overlying clay); and
ii. Springs or groundwater seepage.
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f. Any area with a slope of forty percent or steeper and with a vertical relief of ten or more feet except areas
composed of consolidated rock. A slope is delineated by establishing its toe and top and measured by
averaging the inclination over at least ten feet of vertical relief.
The subject site meets the qualification of a landslide hazard area due to the adjacent slope that is greater than 40
percent and is more than 10 feet in vertical height(17.01.100A1f).
SEISMIC HAZARD CLASSIFICATION
The Mason County Critical Areas Ordinance(17.01.102A)defines a seismic hazard area as:
1.Areas susceptible to ground failure including the following:
a.Areas with mapped geologic faults until proven inactive;
b. Deep road fills and areas of poorly compacted artificial fill;
c.Areas with artificially steepened slopes(i.e. old gravel pits);
d. Postglacial stream, lake or beach sediments;
e. River deltas;
f.Areas designated as potential Landslide Hazard Areas;
g. Bluff areas; and
h.Areas underlain by potentially liquefiable soils.
2. The following criteria may be used as a guide by the County to indicate areas that have a higher likelihood of
meeting the classification criteria above:
a. Areas identified on the Coastal Zone Atlas of Washington, Volume 9, Mason County as Af, Qal, Qa2, Qvc,
Qls, Qos and Qp.
b.Areas identified on the Mason County Soil Survey Map as having slopes greater than 15 percent.
c. Faults identified on "Map Showing Known or Suspected Faults With Quaternary Displacement in the
Pacific Northwest", A.M. Rogers, T.J. Walsh, W.J. Kockelman and G.R. Priest, US Geologic Survey, 1996;
or described in "Active Faulting Investigations on the Canyon River Fault, Southern Olympic Range,
Washington", T.J. Walsh and KG. Neal, U.S. Geologic Survey, 1997.
d. Areas underlain by potentially liquefiable soils as shown in "Liquefaction Susceptibility Map of Mason
County, Washington"by Stephen P. Palmer, Sammantha L. Magsino,James L. Poelstra, Eric L. Bilderbacl,
Derek S. Folger, and Rebecca A. Niggemann, September 2004
This site qualifies as a seismic hazard area because the site is categorized as, "l.f. Areas designated as potential
Landslide Hazard Areas."
Beginning approximately 500 feet southwest of the property are a series of landslides that have been mapped as a
continuous feature for over a mile to Fudge Point. Many of these slumps were not seen by earlier mappers, and
these is no reason to consider them as occurring as one event or even being related. Most appear old. The location
of the current residence, as is similar to the north, appears more stable than the bluffs to the south,which is likely
due to the consolidated nature of the soils in the bluffs and lesser undercutting.
The nearest mapped fault of any consequence is the Tacoma Fault located approximately 15 miles to the north-
northeast of the site near Allyn.
This east-west trending feature is one of the numerous faults comprising the Cascadia Fault Zone and is considered
a potential hazard of considerable importance. However, the last activity of note was 1100 years ago, and any
further activity would be regional in scale. This means that risk is present, but the associated accelerations are
modeled in our slope stability program. Western Washington is seismically active, and any structures must be
built to applicable earthquake standards.
AAG10-016 8947 Buttonwood Lane NE,Olympia, WA 98516 10
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EROSION HAZARD CLASSIFICATION
The purpose of the Erosion Hazard Section (I7.01.104A) is to identify areas that present potential dangers to
public health and safety,and to prevent the acceleration of natural geological hazards, and to neutralize the risk to
the property owner from development activities.
Areas in Mason County underlain by soils, which are subject to severe erosion when disturbed.
Such soils include, but are not limited to, those for which potential for erosion is identified in
the Soil Survey of Mason County, USDA Soil Conservation Service, 1960, or any subsequent
revisions or additions to this source. These soils include, but are not limited to, any occurrence
of River Wash ("Ra') or Coastal Beaches ("Cg') and the following when they occur on slopes
15%or steeper:
a.Alderwood gravelly sandy loam('Ac"and "Ad')
b. Cloquallum silt loam("Cd')
c. Harstine gravelly sandy loam ("Hb')
d. Kitsap silt loam ("Kc')
The soils at the residence site are mapped as Sinclair shotty loam, IS to 30 percent slopes (Sp). The area to the
west is all Sinclair shotty loam 5 to 15 percent slope (So). While not technically listed as hazard soils,these will
be considered as liable for potential erosion,as detailed below.
SITE SOILS
The Soil Survey of Mason County, Washington, USDA Soil Conservation Service(1960)has mapped the more
important coastal site soils as Sinclair shotty loam 15 to 30 percent slope(Sp). The Sinclair soils are described as
follows:
SINCLAIR SERIES
The Sinclair series consists of moderately well drained,brown. shotty soils on uplands.They have developed from
very compact Vashon gravelly glacial till in rainfall that ranges from 45 to 55 inches a year-the lowest in Mason
County. The vegetation is a forest, mainly excellent Douglas-fir mixed with cedar, maple, and alder. The
understory is a luxuriant growth of swordfern,Oregon-grape,vine maple, salal,and huckleberry. Compared to the
vegetation on drier adjacent soils,there is very little madrone and manzanita,but there is considerable cedar.
Surface drainage is moderately well established. Internal drainage is medium, except that it is restricted by the
cemented substratum. Sinclair soils are near Puget Sound on the eastern edge of Mason County and on the islands
of Case Inlet. They are commonly on lower slopes adjacent to the Harstine and Alderwood soils. They are grayer,
more finely textured, and more shotty, than either the Alderwood or the Marstine (sic) soils. In addition, the
underlying till, in most places,is more cemented.
Sinclair spotty loam, 15 to 30 percent slopes(Sp). -This soil occupies hilly areas and small canyons adjacent to
Puget Sound in association with other Sinclair soils. It differs from Sinclair shotty loam, 5 to 15 percent slopes, in
that it varies more in depth to the till and in the degree of cementation of till. In the canyons and on the steeper
slopes,small areas of Kitsap,Alderwood,or Harstine soils are included. Under natural conditions,the soil absorbs
moisture readily and runoff is slight. Erosion would be severe if large areas were cleared. Use and suitability.-
Nearly all this soil is in forest, but a few tracts are farmed along with Sinclair shotty loam, 5 to 15 percent slopes.
Trees grow well and respond to management.
The relevance of the soils will be further considered,below.
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SITE GEOLOGY
The site is generally situated within the Puget Sound glacial province. The existing topography, as well as the
surficial and shallow subsurface soils in the area, is the result of the most recent Vashon stade(stage)of the Fraser
glaciation that occurred between about 9,000 and 11,000 years ago, and weathering and erosion that has occurred
since. A description of the surficial soils is included in the"Site Soils"section of this report. In general,the units
are composed of glacial material.
The area consists of various continental glacial deposits with locally exposed pre-continental deposits lying
underneath. Because of the steepness of the bluffs locally,these are commonly undifferentiated in map-view(Qu).
The primary surface unit is the Vashon glacial till(Qgt),described as follows.
The Geologic Map of the Shelton 1:100,000 Quadrangle, Washington, by Logan (2003) describes the site as late
Wisconsinan(Pleistocene)glacial deposits. The glacial till(Qgt)is described as:
Till, late Wisconsinan (Pleistocene)—Unsorted, unstratified, highly compacted mixture of clay,
silt, sand, gravel, and boulders deposited by glacial ice of the Puget lobe; gray; may contain
interbedded stratified sand, silt, and gravel; sand-size fraction is very angular and contains
abundant polycrystalline quartz, which distinguishes this unit from alpine till; cobbles and
boulders are commonly striated and(or)faceted, although unweathered almost everywhere, may
contain cobbles or small boulders of deeply weathered granitic rock
The Geologic Map of the Vaughn 7.5-minute Quadrangle, Washington, by Logan and Walsh (2007) provides the
most recent mapping. It shows the extensive Qgt but also includes a geologic column from a nearby bluff. The
succession begins with the Qgt,it is underlain by the following:
Qgt-described above
Qpg-Pre-Vashon deposits of unknown age,coarse-grained
Qps-Pre-Vashon deposits of unknown age,fine-grained
These are lying on an even earlier thin layer of lacustrine sediments,themselves overlying a well-indurated earlier
glacial till.
The Qgt and Qpg are mapped as 20' thick, which is observable on-site. Thickness of the remaining units is not
seen due to vegetation. However, the 1999 report refers to "well compacted" sediments and that the "slope is
sound." The earlier data will be used to model the bluff and building location later in the text.
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SUBSURFACE EXPLORATIONS
Subsurface conditions at the site were evaluated by observing the exposed site soil,reviewing available well logs,
reviewing published reports and the 1999 GTL report which included sampling under the current residence.
The hand borings were accomplished at the time with a 4-inch diameter hand auger. Samples were obtained by
recovery from the auger. The GTL soils laboratory has the following certifications, accreditations, or
qualifications:
AASHTO American Association of State highway and Transportation Officials
AMRL AASHTO Materials Reference Laboratory
CCRL Cement and Concrete Reference Laboratory
ICC International Code Council
SUBSURFACE CONDITIONS
Beneath the soil horizons, the site is
underlain entirely by what appears to be y'
Vashon till,overlying competent pre-Vashon
soils. These units of mixed composition are :
locally very hard, but the degree of
induration varies. The exact subsurface
profile cannot be seen without a thorough `
investigation of the bluff, but the
observations from the visit and the earlier
report support a compact mass that shall be
modeled monolithically.
The nearest well found in the Ecology well rt .
search is a deep well with a static water table
of 95 feet on the Noble property at 100 Ash
Lane. This was drilled for a community well
and logged by a geologist.
Factors such as amount of rainfall, runoff, etc. affect the fluctuations in the groundwater levels. These factors
contribute to the shallow water and are not considered important to the overall geologic model. However,the
shallow water may be important to the drainage of a site. The surface water situation is not clear at this site
due to the use of matting and the presence of lined ponds. Thus, designers and contractors should take this
into account.
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SLOPE STABILITY AND ANALYSIS
The Coastal Zone Atlas, Volume 9, Mason County(MA-14) maps most of the site as Vashon glacial till(Q,t). This
is the same as the Qgt described in GEOLOGY, above. Foundation stability is described as "excellent." Seismic
stability is described as"good." The slope stability is described as"stable"except at the"unstable"bluff.
Evidence of significant recent erosion was observed onsite only locally at the bluffs, where water run-off has cut
some notches at the lip and degraded the bluff-face at the time of our investigation. Creep was present and
common at the bluff.
The near-surface soils are in a dense to very dense condition except at the ground surface. The surficial soils are
generally in a medium dense condition. These are hidden over much of the property by a fabric cover.
In general,the undisturbed native soils of the site consist of a mixture of variable amounts of sand, silt,and gravel.
These soil materials are in a dense condition except where they have been disturbed by weathering activity. No
evidence of deep-seated landslide activity or significant erosion was observed onsite at the time of our
investigation. Landslide activity was observed along the eastern coastal bluff.
Weathering,erosion,and the resultant sloughing and shallow landsliding are natural processes that can affect steep
slope areas. Instability of this nature is typically confined to the upper weathered or disturbed zone, which has
been disturbed and has a lower strength. Any bluff unprotected by vegetation will be attacked by rainfall,both by
impact and drainage. The toe of the bluff is likewise exposed to wave and storm erosion.
Significant weathering typically occurs in the upper 2 to 3 feet and is the result of oxidation, root penetration,
wet/dry cycles,and freeze/thaw cycles. Encouraging vegetation and discouraging runoff from the steep slopes can
reduce erosion in steep slope areas such as this.
A mat of material designed to discourage and eliminate natural growth has seriously altered the surface area of
this property and will contribute to bluff erosion if not corrected. This mat covers a large surface area and laps
around tree-trunks. The exact area is not known,or if the mat is continuous. But it is extensive. Although the mat
is covered by bark that ranges from 0 to 3 (±) inches thick, it slopes in large measure toward the bluff. The only
vegetation, outside of scattered trees, is where water has imponded and allowed enough rooting for weeds and
opportunistic species to take hold. The material appears impermeable and, if so,water will flow down to the bluff
where it will overflow the lip and cause damage. In fact,a half-log weighted with rock appears to be a water-break
at a point where water would flow over the bluff at the tight line(from roof drains?)descending down the bluff.
There is the possibility that the material is somewhat permeable,permitting some infiltration into the soil below. I
could not tell if this were so at the time of the visit. However, it appears the previous owners sought to maximize
the clear areas but avoid lawn and garden maintenance by this expedient. If impermeable, remediation, including
removal of much of the mat,will be required.
Remediation and enhanced erosion control recommendations for the property are provided in the "Erosion
Control"section of this report.
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17.01.100E5 (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.
Slope stability was modeled using the GeoStudio 2007 program (version 7.16) in both static and dynamic
conditions (Ca = 0.15). "Static" condition refers to an "as is" state of a given slope. "Dynamic" puts seismic
acceleration into the model for earthquake conditions.
Factors of safety were determined using Bishop, Ordinary, and Janbu methods. The site was modeled in a
monolithic layer. The parameters used in this modeling were based on the report prepared on September 3, 2009
and our experience with the surroundings and the types of materials encountered on site. The parameters are
provided in the modeling itself.
Under static conditions,the slope generally showed susceptibility to deep-seated stable to deep-seated and shallow
failure. See Figure 4 for the cross-sections. Under dynamic loading (Ca=0.15), the 3328 computations
demonstrated that the slope is safe and not susceptible to a deep-seated movement. The following are the Factors
of Safety(FoS)attained for the section with respect to its current topographical representation.
Section Factor of safe (Static) Factor of safe (Dynamic)
AA' 1.50 1 1.10
These calculated Factors of Safety meet the requirements set forth by Mason County that is, 1.50 for static and 1.1
for dynamic loading scenarios. Based on our slope models representing critical slopes at the subject site, it is
apparent that the building site is not susceptible to damage by deep-seated movements or instability.
AAG10-016 8947 Buttonwood Lane NE,Olympia,WA 98516 15
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SLOPE MODELS
EVANS PROPERTY
SLOPE MODEL AA'
STATIC '
FoS: 1.50 • • •
120 • • • •
„0 • ' •
100 - EXTG. BUILDING • •' .
•
80 •
C70 • •
Name: Qgt •
w Unit Weight: 128 pcf
Cohesion: 80 psf
20 Phi: 37
10
0
,80 _ 220 240 M 290 �O120o
Distance
AAG10-016 8947 Buttonwood Lane NE,Olympia, WA 98516 16
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ALL AMERICAN GLOTECHNICAL, INC.
EVANS PROPERTY '•
SLOPE MODEL AA' •• .
DYNAMIC
FoS: 1.10 '
EXTG. BUILDING
Name: Qgt
Unit Weight: 128 pcf
Cohesion: 80 psf
Phi: 37 °
Distance
AAG10-016 8947 Buttonwood Lane NE, Olympia, WA 98516 17
Phone#: (360)481-6677 Fax#: (360) 754-4848
ALL AMERICAN GEOTECHNIC L, INC.
17.01.100E5 (7) -- Appropriate restrictions on placement of drainage features, septic drain
fields and compacted fills and footings, including recommended buffers and setbacks from
the landslide hazard areas.
Please see below and the Earthwork section of this report.
RECOMMENDATIONS FOR BUILDING SETBACK
The following is for future development.
The building setback may be measured from
the bottom of the footing to the face of the
steep slope in accordance with the
International Building Code (1805.3.1), see
figure to right.
The existing building does satisfy the
minimum required setback as per the se`ha`�
International Building Code.
The existing setback is 60-feet from the top
of the slope.
17.01.100E5(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.
VEGETATIVE MANAGEMENT
Some specific vegetation recommendations are located elsewhere in the report (such as Erosion Control below).
These recommendations are specific to this site
The bluff needs to be protected where vegetation is absent. Temporary nets of jute or similar material may be used
to anchor seedlings or other plants.
If it is determined the matted area described above is draining over the bluff, at least a partial removal should be
undertaken,with the exposed ground secured by lawn or native vegetation.
A revegetation plan should be in place before removal of the fabric. Native species should be considered as the
primary vegetation in areas away from lawn and ornamental plantings, such as the bluff. Do not plant ivy or other
aggressive non-native species. Shallow rooted species, such as grass, should be planted closer than 10 feet from
-underground drainages, septic drainfields and their associated drains,etc.
AAG 10-016 8947 Buttonwood Lane NE,Olympia,WA 98516 18
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ALL A MERICAN GEOTECHNICALI, INC,
Densely rooted evergreen shrubs are preferable than tree species on slopes greater than 15% gradient. Tall trees
may become unstable in wet soils under high wind conditions. Clearing of vegetation must be done to prevent
subsequent erosion by immediate measures to control erosion.
In the upper areas of the property,trees may be replanted. This includes within the 50 foot vegetation buffer, but
for reasons of bluff safety,these should be minimized in the area near the lip.
Conifers should not be topped. The choice of vegetation and the planting locations and maintenance advice should
be provided with the assistance of a professional horticulturist/arborist.
17.01.100E5 (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.
RECOMMENDATIONS FOR EROSION CONTROL
If it is determined that the mat is impermeable, it should be removed and the exposed soil planted with lawn or
native plants. The mat may be retained where water backflows into pre-existing ditches and ponds. All water flow
toward the bluff must be discouraged, with drains or channels intercepting surface water and redirecting it by
tightline to the beach below. The discharge of this and any other tightline should be dispersed by rocks to prevent
beach erosion. Landscaping around the site is permissible, but understory growth on bluffs should be encouraged
as much as possible as a deterrent to erosion.
We believe that mature and large juvenile trees may be removed from the landslide hazard area under the
condition that the stumps be retained in place and non-invasive native vegetation be immediately planted to help
secure the bluff from erosion. Other existing vegetation on the bluff shall be left undisturbed except as needed for
beach access described below. We also believe that trees currently surrounded by the mat have that material
removed to expose the soil above the roots. It is our opinion these procedures can be done with minimal impact on
the erosion potential of the site. We recommend that the site be evaluated by a licensed professional arborist or
horticulturalist experienced in native plants and tree thinning.
Temporary and permanent erosion control measures should be implemented and maintained during remediation to
limit the additional influx of water to exposed areas and protect potential receiving waters. Revegetation should
occur immediately following any construction.
Erosion control measures should include, but not be limited to, silt fences, berms, and swales with ground
cover/protection in exposed areas. Typical erosion control notes and a silt fence detail are included on Figure 2
Site Plan. No re-contouring of the site is anticipated.
AAG 10-016 8947 Buttonwood Lane NE,Olympia,WA 98516 19
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AU, A W R I C AN C E®TECHNICAL,, INC.
17.01.100E5 (10) An analysis of both on-site and off-site impacts of the proposed
development.
SEPTIC IMPACT
Septic pre-exists and poses no problems
Water is provided by an off-site community water system.
17.01.100E5 (11) Specifications of final development conditions such as, vegetative
management, drainage, erosion control, and buffer widths.
Please refer to the Building Setback, Vegetative Management, Figure 2 and Figure 3 for this section. The 50 foot
vegetation buffer can be maintained if care is taken to replace some mature and juvenile trees with native plants
that hold the soil well and the original tree roots are retained in place.
RECOMMENDATIONS FOR SITE DRAINAGE
All ground surfaces, pavements, and sidewalks should be sloped away from the residence and associated
structures. Surface water runoff should be controlled by a system of curbs, berms, drainage swales, and/or catch
basins, and tight lined into the appropriate drainage facilities. We recommend that conventional roof drains be
installed on the proposed porch. Footing drains shall be installed for the porch if new footings are required. The
roof drain should not be connected to the footing drain. For footing drains, the drain invert should be below the
bottom of the footing. Use of pre-existing footing will eliminate the need for new footing drains.
Typical drainage control measures are included on Figure 3. Use of existing drainages is preferred. Onsite
irrigation to lawn areas shall be minimized.
The soils described above should provide adequate drainage,but topsoil may be needed. Bark is abundant.
17.01.100E5 (12) -- Recommendations for the preparation of structural mitigation or
details of other proposed mitigation.
No structural mitigation is predicted for this project. The existing footprint of the patio area will support the load
of a roof as long as it is properly designed for drainage. In addition, using a notch in the lip of the bluff near the
northern edge of the property, a staircase can be erected, as long as it is anchored at the top and at the bottom,
possibly on a future bulkhead. The addition of landings secured to the bluff and designed by an engineer should
not increase the instability of the bluff. The top landing can be secured by pin-piles set back from the bluff so a
slab can be constructed, cantilevered toward the bluff, for example. Free-standing zig-zag stairs with secured
landings are a possible design solution. Figure 2 shows a straight stairway which may be possible.
AAG 10-016 8947 Buttonwood Lane NE,Olympia,WA 98516 20
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ALL AMERICAN GEOTECHNICAL, INC,
17.01.100E5 (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.
A site plan is attached as Figure 2 Site Plan at the end of this report.
EARTHWORK
Little site preparation is anticipated. The following are general guidelines.
RECOMMENDATIONS FOR SITE PREPARATION
The Gravelly Sand tested from onsite is suitable for re-use as structural fill.
Where placement of fill material is required, the exposed subgrade areas should be proof-rolled to a firm and
unyielding surface prior to placement of any fill. Over-excavation in any building area should be backfilled with
structural fill,compacted to the density requirements described in the"Structural Fill"section of this report.
If structural fill is needed,we recommend that a member of our staff evaluate the exposed subgmde conditions
RECOMMENDATIONS FOR STRUCTURAL FILL
All fill material should be placed as structural fill. In general,the structural fill should be placed in horizontal lifts
of 8 inches to allow adequate and uniform compaction of each lift. Fill should be compacted to at least 95 percent
of MDD(maximum dry density as determined in accordance with ASTM D-1557)to grade.
The final appropriate lift thickness will depend on the fill characteristics and compaction equipment used. We
recommend that our field representative evaluate the appropriate lift thickness during construction. Material
placed for structural fill should be free of debris, organic matter, trash, and cobbles greater than 6 inches in
diameter. The moisture content of the fill material should be adjusted as necessary for proper compaction.
RECOMMENDATIONS FOR SUITABILITY OF ONSITE SOILS AS FILL
Onsite soils may be considered for use as structural fill only if industry standards are satisfied. Fill material
requirements are found on page 9-26 to 9-30 of the WSDOT Standard Specifications 2010. In general, a native
soil (sand, silt, and gravel) encountered on a site must have less than 10 percent fines (material passing the US
No.200 sieve)to be suitable for use as structural fill.
AAG 10-016 8947 Buttonwood Lane NE,Olympia,WA 98516 21
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ALL AMERICAN GEOTECHNICAL,, INC.
RECOMMENDATIONS FOR CUT AND FILL SLOPES
No cut-and-fill slopes are anticipated. The following is for completeness.
All job site safety issues and precautions are the responsibility of the contractor providing services and/or work.
The following cut/fill slope guidelines are provided for planning purposes.
Temporary cut slopes may be necessary. As a general guide, temporary slopes of 1.5 to 1 (horizontal to vertical)
or flatter may be used for temporary cuts in the upper few feet of the glacially consolidated soils, if present, that
are weathered to a loose/medium-dense condition. Temporary slopes of 1 to 1 or flatter may be used in
unweathered dense to very dense sand and gravel.
These guidelines assume that,all surface loads are kept at a minimum distance of at least one half the depth of the
cut away from the top of any slopes and that significant seepage is not present on the slope face(due to recent rain
events). Flatter cut slopes will be necessary where significant raveling or seepage occurs.
Surface drainage should be directed away from all slope faces. Straw, hay, or jute matting shall be used to cover
the exposed soils until permanent vegetation is established. All slopes should be seeded as soon as practical to
facilitate the development of a protective vegetative cover,or otherwise protected.
RECOMMENDATIONS FOR FOUNDATION SUPPORT
At this moment no construction outside the deck roof is proposed at the site. The following are the general
guidelines for any future constructions. The bearing capacity is provided based on the native glacial till materials.
If the material encountered during subgrade excavation is not consistent to the described one we should be notified
prior to any further construction.
Where foundation elements are located near slopes between 5 and 30 percent, the footings should be located a
minimum of 2 times the footing width from the slope face (horizontally), and founded in medium dense or denser
native soils or properly prepared structural fill. We recommend the footing depth should be at least 12-inches and
we recommend a minimum width for isolated and continuous wall footings to meet IBC 2006.
Footings founded as described above can be designed using a net allowable soil bearing capacity of 3000 psf
(pounds per square foot)for combined dead and long-term live loads in areas of medium dense to dense soils.
The weight of the footing and any overlying backfill may be neglected. The allowable bearing value may be
increased by one-third for transient loads such as those induced by seismic events or wind loads.
We estimate that settlements of footings designed and constructed as recommended will be less than 1 inch,for the
anticipated load conditions, with differential settlements between comparably loaded footings of'/2 inch or less.
Most of the settlements should occur essentially as loads are being applied. However, uncorrected disturbance of
the foundation subgrade during construction could result in larger settlements than predicted.
AAG10-016 8947 Buttonwood Lane NE,Olympia,WA 98516 22
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ALL l MERICAN GEOTECHNIC LI, INC.
SEISMIC LIQUEFACTION HAZARD
The following geologic excerpts are from the available resources governing seismic liquefaction susceptibility of
the subject site.
The Liquefaction Susceptibility Map of Mason County, Washington by Palmer, Magsino, Poelstra, Bilderback,
Folger,and Niggemann(September 2004)maps the site area as having a very low liquefaction potential.
Soil liquefaction is an episode in which saturated, cohesionless, or granular soils experience a significant drop in
strength due to additional build-up of pore water pressure during cyclic loading such as that induced by
earthquakes.
Based on our review of the subsurface conditions, we conclude that the site soils are only mildly susceptible to
liquefaction. The soils are in a dense enough condition and are not cohesionless. Shaking of the already dense soil
is not apt to produce a denser configuration and subsequently excess pore water pressures are not likely to be
produced, thereby reducing the liquefaction potential considerably. This is in agreement with the mapped
liquefaction susceptibility of the area as quoted above
The Site Class Map of Mason County, Washington by Palmer, Magsino, Bilderback, Poelstra, Folger, and
Niggemann (September 2004) maps the inland portion of the site area as site class C. Site class C is a very stiff
soil or soft rock.
GEOSEISMIC SETTING
According to the Seismic Zone Map of the United States contained in the 2006 International Building Code(IBC),
the project site is located where the maximum spectral response acceleration is 45 percent of gravity(g).
We recommend following seismic factors for design purposes.
• Site Class: C(stiff soil)
• Spectral response acceleration, short period(Sms): 1.16g(Fa= 1.05)
• Spectral response acceleration, 1-second period(SM,): 0.70g(F,= 1.55)
LATERAL EARTH PRESSURES
Lateral loads may be resisted by friction on the bases of footings and floor slabs and as passive pressure on the
sides of footings. An allowable coefficient of friction of 0.40 may be used to calculate friction between the
concrete and the underlying native soil. We recommend the following be used to determine the lateral earth
pressures considering the onsite gravel with silty sand:
• 0(soil friction angle) 37 degrees
• Ko(at rest earth pressure coefficient) 0.40
• Ka(active earth pressure coefficient) 0.25
• Kp(passive earth pressure coefficient) 4.00
• y(soil unit weight) 128 pcf
AAG10-016 8947 Buttonwood Lane NE,Olympia,WA 98516 23
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ALL AMERICAN CEO ECHNICALI, INC.
RECOMMENDATIONS FOR FLOOR SLAB SUPPORT
This section is included for future development.
Before the placing of any concrete floors or pavements on the site,or before any floor supporting fill is placed,the
subgrade should be proof rolled to confirm that the subgrade contains no soft or deflecting areas. Areas of
excessive yielding should be excavated and backfilled with structural fill.
Any additional fill used to increase the elevation of the floor slab should meet the requirement for structural fill.
Structural fill should be placed in layers of not more than 12 inches in thickness, at moisture contents at or above
optimum, and compacted to a minimum density of 95 percent of the maximum dry density as determined by
ASTM designation D-1557.
A granular mat should be provided below the floor slabs. This should be a minimum of four inches in thickness
and properly compacted. The mat should consist of sand or a sand and gravel mixture with non-plastic fines. The
material should all pass a 3/4 inch sieve and should contain less than 10 percent passing the #200 sieve. Because
groundwater can be expected to be at shallower depths during the winter months, a moisture barrier should be
placed beneath all floor slabs.
RECOMMENDATIONS FOR RETAINING WALLS
No retaining walls are anticipated. Information is available on request.
RECOMMENDATIONS FOR RETAINING WALL ALTERNATIVES
Not applicable.
CONCLUSIONS AND RECOMMENDATIONS
GENERAL
Based on the results of our site reconnaissance, subsurface observations, and our experience in the area, it is our
opinion that the site is suitable for development of a roof over the pre-existing concrete deck. We also conclude
that eventually, the client should consider building a bulkhead to protect the base of the bluff and provide a
construction platform for a stairway. The minimum amount of soil removal for such a project should not create a
hazard to the bluff,but caution should be taken to make as little disturbance as possible.
As the yard facing the bluff is currently covered in fabric and bark, the 50 foot vegetation buffer will not be
disturbed by construction of a roof over the existing deck. A waiver can be requested from the County if needed.
Likewise, if a satisfactory engineering solution for a stairway is developed,a platform located at the location cited
above will not injure protective vegetation in the 50 foot zone.
It is our opinion that a stairway on the bluff face should be considered,as it will provide not only beach access but
also a means to inspect and maintain the bluff. The minimal cutting back of vegetation will be paid back in future
ability to help control erosion.
The project will cause no significant environmental impact for the life of the project if guidelines are followed.
AAG 10-016 8947 Buttonwood Lane NE,Olympia,WA 98516 24
Phone#: (360)481-6677 Fax#: (360)754-4848
ALL AMERICAN GEOTECHNICAL, INC.
We recommend that earthwork and construction involving earthwork be undertaken during favorable weather
conditions. This is especially true of removal of the mat,if needed. A French drain or similar capture drain should
be installed below the residence to capture and divert surface flow.
Conventional construction equipment may be utilized for work at the site except close to the edge of the bluff.
Conventional spread footings may be utilized at the site for support of the deck roof if necessary. A vapor barrier
is recommended for all slabs-on-grade.
Revegetation should be done as per recommendations in the text,above.
AAG10-016 8947 Buttonwood Lane NE,Olympia,WA 98516 25
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ALL AMEWAN GEOTECHNIC L,, INC,,
REPORT LimrrATIONS AND GUIDELINES FOR USE
We have prepared this report for the exclusive use of Mr. Brian Evans and his authorized agents for this property
in Mason County, Washington. Site inspections, research, and mapping have culminated in this report. This
report is intended to meet the requirements of the Mason County Critical Areas Ordinance. This report does not
specify setbacks for: line-of-sight setbacks, FWHCA setbacks, eagle tree setbacks, wetland setbacks, or property
line setbacks. Within the limitations of scope, schedule, and budget, our services have been executed in
accordance with generally accepted practices in the field of geotechnical engineering in this area at the time this
report was prepared. No warranty or other conditions,expressed or implied,should be understood.
CONTRACTORS ARE RESPONSIBLE FOR SITE SAFETY ON THEIR OWN CONSTRUCTION PROJECTS
Our geotechnical recommendations are not intended to direct the contractor's procedures, methods, schedule or
management of the work site. The contractor is solely responsible for job site safety and for managing
construction operations to minimize risks to onsite personnel and to adjacent properties.
READ THESE PROVISIONS CLOSELY
Some clients, design professionals, and contractors may not recognize that the geoscience practices(geotechnical
engineering or geology) are far less exact than other engineering and natural science disciplines. This lack of
understanding can create unrealistic expectations that could lead to disappointments, claims and disputes.
Geotechnical Testing Laboratory includes these explanatory"limitations"provisions in our reports to help reduce
such risks. Please confer with Geotechnical Testing Laboratory if you are unclear how these"Report Limitations
and Guidelines for Use"apply to your project or site.
The equipment, techniques, and personnel used to perform an environmental study differ significantly from those
used to perform a geotechnical or geologic study and vice versa. For that reason, geotechnical engineering or
geologic reporting does not usually relate any environmental findings,conclusions or recommendations;e.g.,about
the likelihood of encountering underground storage tanks or regulated contaminants. Similarly, environmental
reports are not used to address geotechnical or geologic concerns regarding a specific project.
AAG 10-016 8947 Buttonwood Lane NE,Olympia,WA 98516 26
Phone#: (360)481-6677 Fax#:(360)754-4848
ALL AMERICAN C EOTECHNIC L, INC.
REFERENCES
MAPS
DeLorme 3-D TopoQuads(2002),Source Data USGS,Yarmouth,Maine.
Derkey, Hehemann, and Alldritt (2009), Geologic Map of the Mason Lake 7.5-minute Quadrangle, Mason County,
Washington, published by Washington State Department of Natural Resources.
Dragovich, Logan, Walsh,and Schasse(2002),Geological Map of Washington-Northwest Quadrant(Geological Map GM-
50),published by Washington State Department of Natural Resources.
Logan(2003), Geologic Map of the Shelton 1:100,000 Quadrangle, Washington, (Open file report 2003-15),by published by
Washington State Department of Natural Resources.
Noble and Molenaar(1970), Geologic Map of Southeastern Mason County, Washington, Water Supply Bulletin 29, Plate 1,
Published by Washington State Department of Water Resources
Palmer, Magsino, Poelstra, Bilderback, Folger, and Niggemann (September 2004), The Liquefaction Susceptibility Map of
Mason County, Washington, published by Washington State Department of Natural Resources.
Palmer, Magsino, Bilderback, Poelstra, Folger, and Niggemann (September 2004), The Site Class Map of Mason County,
Washington,published by Washington State Department of Natural Resources.
Rogers, A. M., Walsh, T. J., Kockelman, W. J., and Priest, G. R. (1996), Map showing known or suspected faults with
quaternary displacement in the Pacific Northwest, published by U.S. Geological Survey OFR 91-441-0, Plate 1,
scale 1:2,000,000.
Smith, Carson(1977), Relative Slope Stability of the Southern Hood Canal Area, Washington, prepared in cooperation with
the Washington Department of Natural Resources Division of Geology and Earth Resources;and, Department of the
Interior United States Geological Survey.
Dragovich, Logan, Walsh, and Schasse(2002), Geological Map of Washington-Northwest Quadrant(Geological Map GM-
50),published by Washington State Department of Natural Resources.
Walsh(1997), The Canyon River fault, an active fault in the southern Olympic Range, Washington: Washington Geology, v.
25,no.4,p.21-24,published by U.S.Geological Survey.
Washington State Department of Ecology (1979), Coastal Zone Atlas of Washington, Volume 9, published by Washington
State Department of Ecology.
PUBLICATIONS
Ambrose(1981),Simplified Design of Building Foundations,Table 2.5,pages 48-57,published by John Wiley&Sons,Inc.
ASTM International(2005),Annual Book of Standards 2005, Section 4, Volume 4.08,published by ASTM International,West
Conshohocken,Pennsylvania.
Bloom(1991),Geomorphology,published by Prentice-Hall,Inc., Upper Saddle River,New Jersey.
Gallagher, Patricia M. (October 27, 2000), Passive Site Remediation for Mitigation of Liquefaction Risk, Dissertation
submitted to the Faculty of the Virginia Polytechnic Institute and State University,Virginia.
AAG 10-016 8947 Buttonwood Lane NE,Olympia,WA 98516 27
Phone#: (360)481-6677 Fax#: (360)754-4848
ALL AMERICAN C EOTECHNICALI, INC.
International Code Council,Inc.(2006),2006 International Building Code,published by International Code Council,Inc.
Kollmorgen Instruments Corporation (1994), Munsell Soil Color Charts (1994 Revised Edition), published by Macbeth
Division of Kolhmorgen Instruments Corporation,New Windsor,New York.
McCarthy(1993),Essentials of Soil Mechanics and Foundations,published by Prentice-Hall,Inc.,Upper Saddle River,New
Jersey.
Moffit(1992),Surveying 91*Edition,published by Harper Collins,New York,New York.
Ness,Fowler, Parvin(1960),The Soil Survey of Mason County, Washington, USDA Soil Conservation Service,in cooperation
with the United States Department of Agriculture, and Washington Agricultural Experimental Station, and the Soils
Conservation Service.
Parks, Neal, Koloski, Laprade, Molinari, Butler, and Lorentson (November 2006), Guidelines for Preparing Engineering
Geology Reports in Washington, published by Washington State Geologist Licensing Board,Olympia,Washington.
Prakash(1981),Soil Dynamics,Figure 6.3,page 173,published by McGraw-Hill,Inc.
Sowers(1979),Introductory Soil Mechanics and Foundations:Geotechnical Engineering,Macmillan Publishing Co.,Inc.
Washington State Department of Transportation(WSDOT)(2005),Standard Specifications for Road Bridge, and Municipal
Construction 2006 M41-10,prepared by WSDOT Engineering Publications,P.O.Box 47408,Olympia,Washington.
WE13SFFES
Mason County Government Information Services
(http://www.co.mason.wa.us)
Mason County Codes,Ordinances,and Regulations
(http://www.co.mason.wa.us/code)
Puget Sound Lidar Consortium
(http://pugetsoundlidar.ess.washington.edu/lidardata/index.html)
Slope Stabilization Erosion Control Using Vegetation A Manual of Practice for Coastal Bluff
(http://www.ecy.wa.gov/biblio/9330.html)
Vegetation Management Guide for Puget Sound Bluff Property Owners
(http://www.ecy.wa.gov/biblio/9331.htm1)
United States Department of Agriculture Natural Resource Conservation Service
(http://soildatamart.nres.usda.gov)
Washington Administrative Code
(http://apps.leg.wa.gov/wac/)
Washington Department of Ecology
(http://apps.ecy.wa.gov/welflog)
(https://fortress.wa.gov/ecy/Coastalatlas/viewer.htm)
AAG10-016 8947 Buttonwood Lane NE,Olympia,WA 98516 28
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ALL AMERICAN G ®TECHNICALI, INC.
APPENDIX
AAG 10-016 8947 Buttonwood Lane NE,Olympia, WA 98516 29
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ALL AMERicAN G-EOTECHNICAL,, INC,
WELL LOG
rtla fMOnal and Mrst Copy with WATER WELL REPORT Application No. .._........
DepartmMt OC Ecology - -
Seeond CaDY-Owner-a Cop? !
Third Copy-DlYller'a Copy�� �( A/ STATE OF WASEMNGTON Permit N4.:L.
(1) OWNER: Nime.-�/-.fl�+K._l+La. L�.�t�r�.......__.....__.._-_-._ Addrer
}; (2) LOCATION OF WELL: county--../_tle4-1 See-39 T.;; .L.i.,R./Ww.M-
0 Geul _and distance fram aecuon or subdivision cornerjlrt)117 E f Z S W GO/
(3) PROPOSED USE: DomaCvrta-7tc,a' Industrial ❑ ifunlefpat D (10) WELL LOG:
W
Irrigation ❑ Test well fl Other ❑ Formation:Damribe by color,charectsr si.-e of materat sad stricture,and
shoe thickne»of aquift*s and the kind and%stars of the moterlal is each
astratum penetrated,r h at[east one entry for each change of formation.
(4) TYPE OF WORK: uwner's number of well - -
(lf more than one).... __ MATERIAL FROM TO
New well Method:Dug ❑ Bored ❑
N Deepened ❑ Cable)K Driven O "-'t---.-----.- --
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(S) DIMENSIONS: Olameter ofinch-
0 _p well_... ..-.._-....._.. _�-(Le,I/A
Drilled..........L..7�.p._.-..ft. Depth of completed well_....jx ._.--.ft. -
-II (6) CONSTRUCTION DpE�TAILS: "— T—- -" -
ft-e Casing installed: Dram.ices .1Z.-ft.to l3 _
Threaded❑ ._..l(2_"Dlam.Loa-l../-1.n.to 13y ft. —_-
wwelded A' fj Dlam.ltoa fa-n.to ..f_ --
d
Perforations: Yes❑ N,!,W Psi 12 40�--A
� Type of perforator used......__-_____._..........._......._..__--.._.._
SIZE of perforations __.. in.by
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0 ..__.....---........perforatiom from_._.�._..tt.m--.------ft.
perforations from_ -.ft.to_.—....._..-..-ft.
......._............perforations from-_...--.ft to_-_._.__.._.__fL
lTf Screens: Y-X No❑ 1 d
•'' Manufacturer'.Name..-I-da-5ply --....__ ..�
Type...Y__^..S41TX_.... M1e�Ota/1
Diem.&M-_Slot else -trma c'i-t=l-..fc.to g.
Slot.Iz60_4-4?&OMM 4Zk..ft.to
r Gravel packed: Yea❑ NoX Siesof gravel: IY/OELX seer fi�_�e
Gravel placed from... .1t.b.. ft,
Surface Seal: Yes>' No O n�a To what depth?- f_��/l/b_
Material used is seal....GE�tdMTdGeJtC�RItfLr.�--- --
2j Did any strata contain unusable water? Yes❑ Nqn _ AID -
Type of water?.....___--_..-.-_--.._Depth of strata
O idethod of sealing strata of_._-
z
(7) PUMP: Manufacturer's Naar n l"
O Type: .-..-..............--
(9) WAT Land surface elevation
QC above meaq xxaaSSl1--evel
T Static level ..J. 1..y_ ... n.below Mp.uiS�1 Data.-f9
O Artesian preaeure ........It..per square inch
._-
OArtesian water to controlledSEP
0 __ --
UJ 9 WELL TESTS: Drawdown Is amount water level Is — ---
( ) lowered below static level work started._._ 9 P-O ettd...._..r _...__,19. P
rF _
0 tvas a Pump test made? Yes No❑ It yes•by whom?-_GSIfCA�E
y Yield: O [al./min.with 1(,.!�2 n_�draw�docw�rt after rjhra. WELL DR$6V$t$c.S7'ISTBMENQJI2 C—E
CA[C T S /O[�G �� This well was drilled under my jurisdiction and this report is
„ true to the beat of my knowledge and belief.
L+ Recovery data (time token as zero when pump turned off) (water level
s" measured from well top to water level) 77
R L NAME.ST..D/.Q -.D��.C�.E..-J�R./.�L./..(Yl�f.....��..._......
Q Time Water Laves I Ttme Water Leesl Time Wets► inea (Vbraon.firm,or corporation) (Type or pelat)
..LP___........._Rs�r ._..'LQ-.Zr ---.. ..F.l.. ...... ._......__......__..r.._. Address.. r......WL1.-- --.................................... ---...-.........
Al...........9s..y.-.r
Sailer th---_ ft.dra down attar....._...-._lies. e�afOl off./lr (will Ort
Artesian flow_...._.».-__.__-.-._._._.-_..g.pm. Date....__.__..-.....�--- //�,( Q (�
Temperature of water_-.._.was a chemical analysis snadef Yes` tgo D License No.........1�C.7...V._-..........__.Date....._!. -.....-_..._..... 19.Q.V
(IISE ADDIITIO'NAL SHEETS M NECESSARY)
8.F.No.7336-OS--f Rev.1.71). j
AAG10-016 8947 Buttonwood Lane NE,Olympia,WA 98516 30
Phone#:(360)481-6677 Fax#: (360)754-4848
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1/2 INCH MINIMUM DIAMETER STEEL ROD
(STRAP)CLAMPED SECURELY TO PIPE
/MAN/ CORRUGATED TIGHTLINE 4 INCH
=`_ ooRR MUM MINIMUM,6 INCH SUGGESTED
-'. ,'`�`�.}�^.j._his. .. }• ♦�it�-�A�.
>av� ..n..�'t�"•-i^ .::,t]. i<: :y�..y:% T:V._.sa..
•"R':T sf��::.S:::a.•:;� .__:•.:.C'..•:.^..'.'S:ifs :c�•:y:+.�.r•'.:«.w
•iar�a)riyt tea,..
TIGHTLINE ANCHORED WITH TWO,
3 FOOT REBAR LENGTHS OR BOLTS.
FLARE END SECTION
QUARRY SPALL
OR ENERGY =`'•'Y `= :� ar;=�
�+^.tw'r't'�-:.:.tr\:w,'k^`.eii-�i�.!•. 'aa •f' i-..'`'�12'•;�y=;Y>^._,.
DISPERSION DEVICE
GRASS-LINED SWALE SHOULD BE A
MINIMUM ONE FOOT WIDE AT THE
BOTTOM AND ONE FOOT DEEP WITH
A MAXIMUM SLOPE OF 5 PERCENT.
MINIMUM 4 FEET
LEVEL SECTION
GEOTEXTILE FABRIC
I
1
I
Geotechnical Testing Laboratory
ceooedmkal seMces 10017 ft—w s1.sw FIGURE 3
OV10k WA W512
�r�igServices ��i544 e12 Ndfasxde DRAINAGE DETAILS
CROSS-SECTION AA'
(NORTHWEST-SOUTHEAST)
140 . . . . . . . . . . . ....... .... . . . . ... . .. . . .. ... . .. .. ....... .. . . . . . ... ..�. . . . -�.P. . . . . .�.�P`\`O. . .... .. . ..... .... ..,.... ... .. . . . .. .
130 . . .. . . .. .. . . .. .. . . .. .. ... �G. . . . . . . .``.h�'� 0. . . . . . . . .. .. ... .. . .. .... .. . . .. .. . .. . .. ...
120 ................_.........._............_...._........................_..........................}.._.._.._........_..__.............._......--_.._.._.._.........................�J.........,........_................_.._...... ............_.........................................--_.._....
110 j.. .. .. . . .. .. . . . . .. . . . . . . .. .. . .. . .. . . . . . .. .. . . .. . .. . .. .. ... . . . .. . .. . . .. .. . . .. . . .. .1
100 .. . .. .... .. .. .. .. .. . . .. . . .. .. .. ... . . . . . . . . . . .. .. . .. . .. .. . . . . . . .. . . .. . .. . .. . � .. .. ... ... . .. . . .. . . .. .
90 .. . .. . . . . . .. .... .. .. .. . . . . . . . . . . . . .. . ... . . . . . . . . . . .. . . .. . .. . .. . I
Ii . . .. .. . ... .. . . .. . . . . .. . . . . a
80 . . .. . . . . . �. ... . . . . . . . .. . . .. . .. . .. ..I. . .. .. ... . .. . .. . .. . . .. .. . . . . .
70 __--- ............................................:..............I
. .... . ......._.._...... ..........._ __.._..__.._.._........- .._...._..__ III ._.._.. - - - ...._......_...._..__...._..__......_
6o Qgt . . . . . . . . . . . .. .. .
A
50 . .. . ... .. .. .. . . . . . .. .. . . . . �o. . . . . . . .. .. ..�. . .. .. .. . ... ... . ... . .. .. . . .. .i
lei
40 . .. . . . . . . . . . . .F, c. . . .. ..I. . .. .. . ... .. ... .... . .. .. . ... .
30 . .. . . . . .. . . . I . .. .. . . .. .. . . . .. . .. .. ... . ..
20 _.._................._......................_................_..__.._.._........ _................_.._............. ........_......_.._.._........_................ ............._Q.g......_.........ti ..................---...._................_...:....................._.._...................._..
T
10 . . . . . . . . . . . . . . . .... ...... . .. . . . ... . .. .. . . . . . .. .... . . .
r
0 150 1100 1150 200 250 1300 1350 400
All American Geotechnical 8947 Buttonwood Lane NE
Olympia,WA 98516 FIGURE 4
Phone:(360)481-6677 SCALE
ill=so' CROSS-SECTIONS
Geotechnical Services Fax:(360)754-4848