HomeMy WebLinkAboutGEO2015-00020 for BLD2015-00299 - GEO Geological Review - 4/22/2015 MASON COUNTY
DEPARTMENT OF COMMUNITY DEVELOPMENT
Planning Division
P O Box 279, Shelton,WA 98584
(360)427-9670
Geotechnical ReportReview Acceptance Letter
June 05, 2015
ERNIE CARINO
8310 E STATE ROUTE 106
UNION WA 98592
Case No.: GE02015-00020
Parcel No.: 322344300110
Proiect Description: GEO REPORT SUBMITTED FOR NEW DETACHED GARAGE (SEE
BLD2015-00299)
The Geotechnical Report for ERNIE CARINO has been received and reviewed by the Planning
Department. The report was prepared by Steve Morta dated 3/5/2015.
Based on the certification provided by the licensed engineer/geologist, the referenced
Geotechnical Report was prepared in general accordance with the requirements in the Mason
County Resource Ordinance, Landslide Hazard Areas 17.01.100.E.5. Mason County considers the
review valid until such time as scope of project, site conditions, and/or regulations change. Should
the scope of work, site conditions, and/or regulations change after the original review, then an
addendum from the original author of the report may be required to address these changes. The
report would only be re-reviewed if a permit for development were submitted after these changes
occur. Mason County does not certify the quality of the work done in this Geotechnical Report.
Please contact me at (360) 427-9670, ext. 365 if you have questions.
Sincerely,
Allan Borden
Land Use Planner
Mason County Planning Department
Comments:
6/5/2015 Page 1 of 1 GE02015-00020
M
Mason County Review Checklist
For a Geotechnical Report
Instructions:
This checklist is intended to assist Staff in the review of a Geotechnical Report. The Geotechnical Report
is reviewed for completeness with respect to the Resource Ordinance. If an item is found to be not
applicable, the Report should explain the basis for the conclusion. The Report is also reviewed for clarity
and consistency. If the drawings, discussion, or recommendations are not understandable, they should be
clarified. If they do not appear internally consistent or consistent with the application or observations on
site,this needs to be corrected or explained. If resolution is not achieved with the author, staff should
refer the case to the Planning Manager or Director.
Applicant's Name: C, "14 W w
Permit# 1! "k3�V�� WMq Parcel# y� / Lt �0 G �U
Date(s) of the Document(s)reviewed: 6 6
(1) (a)A discussion of general geologic conditions in the vicinity of the proposed development,
OK? Comment:
uro UoolUl I UI opt-.UMU SUIT types
t OK? Comment:
..(c) A discussion of ground water conditions. _
OK? Comment:
(d) A discussion of the upslope geomorphology
OK? Comment:
(e) A discussion of the location of upland waterbodies.and-wetlands
OK? Comment:
(f) A discussion of history of landslide activity in the activity in the vicinity as available in the
referenced maps and records
OK? Comment:
(2) A site p1jaTwhich identifies the important development and geologic features.
OK? jZ Comment:
(3) Locations find logs of exploratory holes or probes.
OK?_jLZ Comment:
(4) The area of t e proposed development, the boundaries of the hazard; and associated buffers and
setbacks all be delineated(top, both sides, and toe)on a geologic map of the site.
OK? V Comment.
(5) A minimum of one cross section at a scale which adequately depicts the subsurface profile, and
which into orates the details of proposed grade changes.
OK?__V Comment:
(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 s ety factor is 1.1. and the quasi-static analysis coeffients should be a value of 0.15.
OK? Comment:
(7) (a)Appropriate restrictions on placement of drainage features
OK? Comment:
(b) Appropriate restrictions on placement of septic drain fields
K? Comment:
40 c) Appropriate restrictions on placement of compacted fills and footings
OK? Comment:
(d) Recommended buffers from the landslide hazard areas shoreline bluffs and the.tops of other
slopes on the property.
Page 1 of 2 Form Effective June 2008
I
OK? Comment: -
(e) Recomm ded setbacks from the landslide hazard areas shoreline bluffs and the top
s of
others pes on the property. ;
OK? Comment:
(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 egetation removal.
OK? V Comment:
(9) Recommendations for the preparation of a detailed temporary erosion control plan which
identifies the s ecific mitigating measures to be implemented during construction to protect the
slope from osion, landslides and harmful construction methods.
OK? Comment:
(10) An analysis both on-site and off-site impacts of the proposed development.
OK? 1Z Comment:
(11) Specification of final development conditions such as, vegetative management, drainage,
erosion co rol, and buffer widths.
OK? Comment:
(12) Recommendagons for the preparation of structural mitigation or details of other proposed
mitigation. /
OK? �/Comment:
(13) A site map rawn to scale showing the property boundaries, scale, north arrow, and the location
and natur of existing and proposed development on the site.
OK? Comment:
Are the Documents signed a d stamped? .
Type #of License: � ��
..
If not approved, what is the next action/recommendation for further action?
Reviewed by , on
Time spent in review:
SECOND REVIEW/ UPDATE:
Reviewed by on
Time spent in second review:
THIRD REVIEW/ UPDATE:
Reviewed by , on
Time spent in third review:
Disclaimer: Mason County does not certify the quality of the work done in this Geological Assessment
Page 2 of 2 Form Effective June 2008
• . �ED 2oc� - D� ZC7 � /7
- . -�,�I cl 20�5 • C�Z�i�
GEOTECHNICAL ENGINEERING REPORT FOR
DETACHED 28' x 28 DOUBLE CAR GARAGE
8310 E. SR-1067, UNION, MASON COUNTY, WA
98592 PLANNING
(Parcel #: 32234-43-00110) RECEIVED
APR 2 2 2015
426 W, CEDAR ST
Prepared for: Ernest Carino
1584 McNeil St. #200
Dupont, WA 98327
(360) 686-6165
Prepared by: MET Engineering, PLLC
1018 E. Wishkah St.
Aberdeen, WA 98520
(360) 310-0270 b
(360) 289-0958 c
(360) 861-8493 f
Contact: Steven P. Morta, P.E.
e-mail: Smortana,aol.com
oWAS 0'�'T
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30 ER�o
SIGNAL ECG`
March 5, 2015
• 2 17
Mar. 5,2015
Page 1 of 4
MET ENGINERING, PLLC
To: Ernest Carino
1584 McNeil St.#200
Dupont,WA 98327
(253)686-6165 c, EJCarino43@yahoo.com
Subject: GEOTECHNICAL ENGINEERING REPORT FOR PROPOSED 28' x 28'
DETACHED GARGE Located at 8310 E.SR-106,Union,Mason County WA
(Parcel#:32234-43-00110)
Introduction
On Friday February 20,2015 this geotechnical engineer registered in the State of Washington as
a Professional Engineer was on site to perform a soils and slope stability investigation of the
relatively steep slopes within 300 feet of the property. This report will discuss the overall long
term stability of the general area including the addition of an 8"thick concrete retaining wall that
will be made part of the south wall of the proposed 28'x 28' detached garage.
Digital color photographs were taken of the surrounding area located on the south side of Hood
Canal including the 2:1 (H:V)slopes on the right hand sand of the proposed garage. An existing
riprap retaining wall was observed on the south side of the proposed building site which helping
to hold back and reinforce the toe of the 2:1 slope. A detailed slope stability analysis has been
included in this geotechnical engineering report as well as digital color photographs that were
taken of the trees and the adjacent properties. Conclusions and recommendations will be
provided at the end of this report.
General Description of the Area
The proposed building site for the 28' x 28' detached garage is located on the south side of SR-
106 at the base of a forested hillside while the actual residence was constructed on the north side
of SR-106. A septic drainfield is located on the uphill side of the south parcel which is typical
for the Hood Canal region.
The hillside is fully forested with 60 to 80 year old firs. There also appears to be a plateau
located approximately 30 to 40' up the toe of the slope which increases long term slope stability.
If there should be a slide in the future,most of the slide material will rest on this relatively wide
plateau area.
There are residences on both the east and west sides of the property and the residential
structures appear to be stable with no signs of any structural damage or cracking from the uphill
slopes. Furthermore, no creeks, streams or seeps were observed on the property. An existing 5
foot high 2 to 3 man quarry rock retaining wall was constructed at the base of the slope with no
1018 E.Wishkah St.,Aberdeen,Washington 98520
(360)289-0958 Bus,(360)861-8493 Fax,(800)590-0958 Toll Free
Smorta@AOL.com
Mar. 5,201.5
Page 2 of 4
MET ENGINERING, PLLC
signs of leaning. It appears that this quarry rock retaining wall has been in place for over 15 to
20 years and helps to anchor the toe of the 2:1 slope.
Geology
Most of the Pacific Northwest area had been covered with extensive glaciers that advanced and
receded at least four times in the last 10,000 to 40,000 years ago leaving sands, silts,and smooth
gravels during the last recession. Also, prior to this period there had existed an inland sea that
existed a few million years ago and left compacted silt and sand deposits. A good example of
this deposit from the inland sea is seen on the north side of SR-12 as one is entering the city of
Aberdeen, WA. This near vertical face consists of very dense clay silt that had been compacted
by the pressure of the seawater. Upon closer examination 12"to 24"nodules can be seen in the
cut face which is the result of deposition from the inland sea. The region around and within
Puget Sound is the remnants of this inland sea which at one time extended all the way up into
Canada and now this northwest region has been identified as the Salish region in recognition of
the native American tribes in this Pacific NW region.
Due to the tectonic plate contact between the Pacific and North American tectonic plate, the
North American plate continues to rise as the Pacific plate continues to slide underneath it. The
region along the Washington State, Oregon, and California coastline is called the subduction
zone which is the primary reason why there has been a number of earthquakes along this fault
zone and is normally called the "Ring of Fire"which includes New Zealand, Japan,Alaska, the
West Coast of the U.S., and Chile in South America. In addition, remnants of volcanoes such as
Mt. Baker, Mt. Rainier, Mt. St. Helens, Mt. Adam and Mt. Hood all lie along this subduction
zone.
Soils
The native insitu soils consists of very gravelly sandy loam which originates from glacial
deposition that occurred over 10,000 years ago. The rocks and cobbles are mostly smooth and
round due to the grinding action of the retreating glaciers.
The soils have been identified by the Natural Resource Conservation Service in their Web Soil
Survey as Alderwood gravelly sandy loam,30 to 50 percent slopes(Ad). A geoprobe was used to
determine the allowable soil bearing capacity of at least 1500 pounds per square foot(psf)which
is more than sufficient to support a 28'x 28' detached garage.
Slope Stability
A slope stability analysis for the uphill side of the residence was completed using the Simplified
Bishop's Method of Circles with the detailed calculations incorporating soil and slope
parameters such as slope height, angle of slope, density of the soil, soil cohesion, as well as the
internal friction angle of the silty loam soil. Reference is made to engineering Sheet 2.0. The
resulting safety factor for the slope stability analysis for the static case was 1.3026 and since this
1018 E.Wishkah St.,Aberdeen,Washington 98520
(360)289-0958 Bus,(360)861-8493 Fax,(800)590-0958 Toll Free
Smorta@AOL.com
7
Mar. 5, 1015
Page 3 of 4
MET ENGINERING, PLLC
value is less than then the normally accepted value of 1.500, the slope was considered unstable.
Similarly, for the quasi-static case, i.e.,the seismic case, the resulting factor of safety resulted in
1.0809 and since this was less than the normally accepted value of 1.100,this too was considered
unsatisfactory,and,therefore,the slope was considered unstable.
The primary slope stabilization mitigation measure is to build into the south side of the garage
wall an 8" thick concrete wall so that the garage would be protected in case of a slide. It is
recommended that this built-in concrete retaining wall continue along the entire south wall of the
garage or 28 feet. This will complement the 2 to 3 man rock retaining wall that is helping to
anchor the toe of the existing slope
Up Slope Conditions
As mentioned earlier, there was a plateau approximately 25 to 30' upslope and then it leveled
out onto a plateau which increases slope stability. In case there is a slide this plateau will
prevent most, if not all, the slide material from coming in contact with the 28' x 28' garage
below.
The uphill slopes were heavily vegetated with 60 to 80 year old firs which increases long term
slope stability through their extensive root systems. Through the process of evapotranspiration,
the root help to remove excess moisture from the soils since they absorb water and evaporate this
moisture out throughout the branches. The upland geomorphology came about through the
deposition of glacial till soils that during the last glacial advance and recession that occurred over
10,000 years ago.
There were no signs of any creeks, streams, wetlands or seeps that could potentially cause a
slide due to saturated soil condition if the creeks or streams should overflow their banks due to
extensive long duration storm events.
Conclusions and Recommendations
1. It is recommended that at least half of the south wall of the 28' x 28' detached garage be
constructed of an 8" thick concrete wall which would also serve as a retaining wall in
case there should be a slide. This concrete wall would then protect the main structure
from damage. The ends of the concrete wall can be further stabilized with a 4'wing wall
that is perpendicular to the main wall that increases long term stability of the wall.
Another 4' perpendicular wall can also be constructed at the midpoint of the retaining
wall for further reinforcement.
2. The existing 2 to 3 man quarry rock retaining wall located on the south side of the
proposed garage can stay since it is helping to anchor the toe of the 2:1 slope. There
were no signs of the rock wall leaning or any other signs of distress on this rock wall that
appears to have been constructed to make room for a building site.
1018 E.Wishkah St.,Aberdeen,Washington 98520
(360)289-0958 Bus,(360)861-8493 Fax,(800)590-0958 Toll Free
Smorta@AOL.com
S/q
Mar. 5,2015
Page 4 of 4
MET ENGINERING, PLLC
3. The existing trees on the uphill slopes should be preserved and left undisturbed since
they significantly help to increase overall slope stability through their extensive root
systems.
4. The downspouts for the 28' x 28' garage need to be directed at least 10' away from the
structure in the direction of SR-106 which is approximately 40 to 50' away. Thus,most
if not all of the downspout runoff should have percolated back into the ground prior to
reaching the drainage ditch along the south side of SR-106.
5. It is recommended that at least 3' of working space be maintained on the south wall of
the garage. Thus, if there should be a slide event,that there would be at least a 3' space
where soils can collect and settlement, thus, minimizing any impact on the south side
garage wall. In addition the 8" thick concrete wall built into the garage wall will also
minimize any damage to the garage structure itself.
6. Footings for the 8"thick concrete retaining wall shall be compacted with a jumping jack
or equivalent to ensure a non-yielding flat surface prior to forming for the retaining wall
footing.
7. The on-site and off-site impacts of the proposed 28' x 28' detached garage is minimal
since the building site has ah-eady been cleared and leveled and ready to build.
8. It is the conclusion of this geotechnical engineer, that if the recommendations are
followed in this geotechnical engineering report, that the likelihood of a slide event can
be kept to a minimum.
This geotechnical engineering report has been prepared per accepted geotechnical engineering
standards. Any questions or comments can be addressed by e-mail at Smorta@aol.com or by
calling this engineer at(360)289-0958.
11k4e,4 cS
EN P.
Respectfully, of WAsy���,'�
�O 30758 <v�
Steven P. Morta, P.E. Ss��NALE�G`��
i
1018 E.Wishkah St.,Aberdeen,Washington 98520
(360)289-0958 Bus,(360)861-8493 Fax,(800)590-0958 Toll Free
Smorta@AOL.com
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This is the location of Ernest Carino's Hood Canal residence at 8318 SR-106,Union,
WA with a parcel 432234-43-00103
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This parcel is located on the south side of 8311 E. R-106 Union, A with r p S , U o , W th a parcel
number of 32234-43-00110. The actual residence is located on the Hood Canal
waterfront at 8311 E. SR-106, Union, WA with a parcel number of 32234-43-0010.3.
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The trees on the slope were growing near vertical indicating long term slope
stability. If the slope was incrementally moving downward the tree trunks would be
curved to compensate for the downward movement and eventually be pistol butted.
These trees are 60 to 80 years indicating that the slopes have been stable for at least
that long.
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The 4-1/2' high riprap retaining wall can be seen in the lower half of the photograph
above and was constructed to help anchor the toe of the slope. The rock retaining
wall also provides a building site for the 28' x 28' detached garage. Reference is
made to Engineering Sheet 1.0 which shows the overall siteplan and the location of
the detached garage.
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Report—Map Unit Description
Mason County,Washington
Ad—Alderwood gravelly sandy loam,30 to 50 percent slopes
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Map Unit Setting
i National map unit symbol:2t626
J 1r I. Elevation:0 to 1,000 feet
" ~ - - •,- .Mean annual precipitation:20 to 60 inches
�r ,Mean annual am temperature:46 to 52 degrees F
fv Frost-free period:160 to 240 days
Farmland classrication:Not prime farmland
- Map Unit Composition
A ,x 41der"vood and similar sods:80 percent
Minor components:20 percent
Estimates are based on obser✓ations,descriptions,and transects of
" the mapunit.
Description of Alderwood
Setting
Landform:Ridges,hills
Landform position(two-dimensional):Backslope
r Landform positron(three-dimensional):Side slope,nose slope,talf
Down-slope shape:Linear,convex
5 t 4cross-slope shape:Convex
_ Parent material:Glacial drift and/or glacial outwash over dense
,. >. glaciomarine DEPOSITS
Typical profile
4-0 to 7 inches:gravelly sandy loam
awl-7 to 21 inches:very gravelly sandy loam
Bw2-21 to 30 inches:very gravelly sandy loam IiI
" Bg-30 to 35 inches:very gravelly sandy loam
t 2Cd1-35 to 43 inches:very gravelly sandy loam
2Cd2-43 to 59 inches:very gravelly sa
Properties and qualities ,
Slope:30 to 50 percent t
Depth to restrctive feature:20 to 39 inc: d
Natural drainage class:Moderately well `8
Capacity of the most limiting layer to tri �.
low to moderately low(0.00 to 0.06 I
Depth to water table:About 18 to 37 inc ;
Frequency of flooding:None
Frequency of pondmg:None v
4variatle rater storage in profile:very i
Interpretive groups v
Land capabrbt,classification(irrigated): o
Land capability elassrfication(nonrrrigate
Hydrologic Sod Group:B
Minor Components
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N.W OVERALL SITEPLAN FOR 28'x 28'DETACHED GARAGE N.E. /
PROPERTY PARCEL#32234-43-00110 PROPERTY l ��
CORNER SR-106 RIGHT-OF-WAY CORNER
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116 FEET (NORTH PROPERTY LINE)
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RESPECT TO SR-106.
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IDENTIFIED. A BACKYARD SETBACK CAN THEN BE
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ALLOWABLE SOIL BEARING CAPACITY S d
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ALLOWABLE SOIL BEARING CAPACITY 10 5
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DETACHED
GARAGE
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ooOjooC o 80 0 0 2:1 H: SLOPE ON THIS SIDE SPACE FOR GARAGE $v
NALti� 20' �o o o c o o c - #1 ( )
o� o o o°G o �C o° o y o '��° o 28'x 28'GARAGE (REFER TO CROSS-SECTION AA-AA) w
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Slope Stability Calculations (Simplified Bishop's Method of Circles)
25 ft 31
Rotational Failure 14otto scale(NTs)
Plane
i
Alpha=42:41 deg
(90%slope)
1. Compute factor of safety(FS)against sliding-Static Case(Ref: "Stability Charts for Uniform Slopes"by
Radoslaw L. Michalowski, F.ASCE) - "Journal of Geotechnical and Geoenvironmental Engineering",April 2002.
From Figure 3"Stability charts for uniform slopes"the following parameters are known for Alderwood gravelly
sandy loam soils:
c(cohesion)=200 psf, gamma(insitu unit density)=135 pcf, H(height of slope)=25 ft,
phi(internal friction angle)=29 deg, then
c/[gamma x H x tan(phi)]=200/(135 x 25 x tan 29)=0-1069
Then for a 42 deg(90%)slope from Fig. 3:
FS/tan(phi)=FS/tan(29)=2.35 or, FS=Factor of Safety Against Sliding= 1.3026<1.500 NOT OKAY
Mitigation Measure Design into the south wall of the detached garage an 8"thick concrete wall to protect from slides.
2. Compute factor of safety(FS)against sliding-Quasi-Static(seismic)Case(Ref: "Stability Charts for Uniform Slopes"
by Radoslaw L. Michalowski, FASCE) - "Journal of Geotechnical and Geoenvironmental Engineering",April 2002.
From Figure 4"Stability charts for uniform slopes"the following parameters are known for Alderwood gravelly
sandy loam soils:
c(cohesion)=200 psf, gamma(insitu unit density)= 135 pcf, H(height of slope)=25 ft,
phi(internal friction angle)=29 deg, then ��N P.MC
wasyr �T
c/[gamma x H x tan(phi)]=200/(135 x 25 x tan 29)=0.1069
Then for a 42 deg slope(90%slope)from Fig.4 for a quasi-static analysis coefficient of 0.1:
F/tan(29)=2.15 or FS=Factor of Safety= 1.1918 30758 q`L�
GISTER�
For a quasi-static analysis coefficient of 0.2: �SSjONALti�G
F/tan(29)= 1.75 or FS=Factor of Safety=0.9700
Asa result,for a quasi static analysis coefficient of 0.15,the Factor of Safety,FS=(1.1918+0.9700)/2= 1.0809<1.100 NOT OKA
Mitigation Measure: Design into the south wall of the detached garage an 8"thick concrete wall to protect from slides.
Slope Stability Analysis for Property Located at
8310 E. SR-106, Union,WA, (Parcel#32234-43-00110) Prepared by: MET Engineering,PLLC,1018 E.VVystdcah St,Aberdeen,VVA 98520
1 (360)289-0958, (800)590-0958,(360)861-8493 fax,Smorta@aol.com
Prepared for:Ernest Carino,1584 McNeil St.#200
Dupoont,WA 98327,(253)686-6165 c. Mar.5,2015 Site Visit on Fri.2-20 2015 SHEET 2.0
at 10:00 am
Mason County Department of Community Development
Submittal Checklist For a Geotechnical Report
Instructions: --- —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 L�l` P_�S f 6,ri&, 0 Parcel# ' Z
Site Address Cf ��� �. W-106 _1j7/vita)
J(1) (a)A discussion of general geologic conditions in the vicinity of the proposed development,
Located on page(s) /
(b) A discussion of specific soil types
Located on page(s) 2
(c) A discussion of ground water conditions
Located on page(s) 3
(d) A discussion of the upslope geomorphology
Located on page(s)�R
(e) A discussion of the location of upland waterbodies and wetlands
Located on page(s) j
(f) A discussion of history of landslide activity in the activity in the vicinity. as available in the
referenced maps and recF rds
Located on page(s) > E�h__IhCe
(2) A site plan which identifies the important development and geologic features.
Located on Maps)�7 ��icfPrii? r T f
(31 Locations and logs of exploratory holes or probes.
Located on Map(s)
J
(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) C�a iYIe ywt A 6)
(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)—_ f PG t/_ O
(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 coeffients should be a value of 0.15.
Located on page(s)��Gfi�b jh 4 0
r
(7) (a)Appropriate restrictions on placement of drainage features
Located on page(s) / 24-e i yp
(b) Appropriate restrictions on placement of septic drain fields
Located on page(s) CC,j'G 0 C/ wolf,?Id
(c) Appropriate restrictions on dacement compacted fills and footings
Located on page(s) 7-
Page 1 of 2 Form Effective June 2008
Disclaimer: Mason County does not certify the quality of the work done in this Geotechnical Report.
7/
7
(d) Recommended buffers from the landslide hazard areas shoreline bluffs and the tops of other
slopes on the pro rty
Located on page(s) . D
(e) Recommended settlacks from fhe landslide hazard areas shoreline bluffs and the tops of
other slopes on the property.
Located on page(s) �i' mill . �l�f/, D
(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)
(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) S;-fe C, Ad cle6ere01
(10) An analysis of both on-site and off-site impacts of the proposed development.
Located on page(s) �Z �s"r 7
(11) Specifications of final development conditions such as, vegetative management,drainage,
erosion control, and buffer widths.
Located on page(s)
(12) Recommendations for the preparation of structural mitigation or details of other proposed
mitigation.
Located on page(s) �pJP�Cf21r�U [�` ��'!��� 04W,-/ir{e- Ykf� WiJ'i5 U-)c�jr/
(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) Sheet j O
hereby certify under penalty of
perjury that I am a civil engineer licensed in the State of Washington 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=�j Zd/�'and entitled ooCopn�f
`7"?5r ZP ;6 Zd- L}e4Z'C_L'1 rs ru u meets all the requirements of the Mason
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)
Cot1 P.Al
wA.S11
TcZ
p ,pF30758�p av' .
CISTE�
�`rSIONA'L
Page 2 of 2 Form Effective June 2008
Disclaimer: Mason County does not certify the quality of the work done in this Geotechnical Report.
r
N.W OVERALL SITEPLAN FOR 28'x 28'DETACHED GARAGE N,E,
PROPERTY (PARCEL#32234-43-00110) PROPERTY 4jr (/
CORNER SR-106 RIGHT-OF-WAY -- — CORNER
116 FEET (NORTH PROPERTY UNE) -
1C. N
'A 1
RP�Np1GV --- REFE TO PARCEL MAPFOR F o
110� �pE OFT R PROPERTY V ON
NTOPER TH `-
u
RESP CT TO SR-106.
to
_ "v
I fV
NOTE: ONCE PROPERTY C DRNERS HAVE BEEN FOUND THEN b
THE EAST PROPE LINE CAN BE LOCATED AND
IDENTIFIED. ABA KYARD SETBACK CAN THEN BE
ESTABLISHED.
P.tiff)
WASq�N T7
6j� P
514 yr OZ a
❑ LIGHT BROWN ALDER GRAVELLY SAND LOAM(Ad) A"A 30758
WITH 2 TO 3"DIAMETERS DOTH ROCKS ANDA 1500 PSF
ALLOWABLE SOIL BEARIN CAPACITY FSS/ONAL t 6
N
DARK BRONM ALDE OGRAVELLY SAhetQAM(Ad) LL
WITH 3 TO 4'SMOOTH CC PSF 18 8
ALLOWABLE SOIL BEARIN CAP C�
DRIVEWAY
FROM SR-106
•��V�V � v 9
2x � OL
� DETACHED
zo GARAGE 2_0 115— G 2
N,A DATUM •.7J y�s
ELEVATION _
Qc� TYPICALCR—SECTION AI AA
7� 50 + 8"CONCRETE WALL
WITH 4'WALL SUPPORTS FA C
Z SOIL r3d I s
III i
$2
30 MAINTAIN MIN.3'BUFFER m
FROM TOE OF SLOPE c
S� - - - - - - - - - - -- (DUE TO LIMITED AVAILABL x
20' �sr 2:1(H:V)SLOPE ON THIS SIDE SPACE FOR GARAGE)
2V x 2V GARAGE (REFER TO CROSS-SECTION AA-AA) n
� haw
a'n
,B �EO 26 I'S - 0002o N
B'x iG OHGD w
ON WEST SIDE o
V o�
1B0' qY lYY TO' iV
a