HomeMy WebLinkAboutGEO2020-00020 for BLD2020-00275 - GEO Geological Review - 12/21/2019 � 0 2OZO - 6W2,0 ` ~ f 4 w
Z620 60arl RECEIVED
MAR 10 2020
PLANNING 615 W. Alder Street
Geotechnical Report
Final Vision Single Family Residence
251 nE
XXX Larson Blvd, Belfair
Parcel No. 12330-50-00092
Mason County, Washington
December 21, 2019
Project# 19238
Prepared For:
Final Vision, Inc.
PO Box 3118
Belfair, Washington 98528
Prepared By:
Envirotech Engineering
PO Box 984
Belfair, Washington 98528
Phone: 360-275-9374
PAL CLYpF ST
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f 43045.E
12/21/19
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MASON COUNTY Submittal Checklist
COMMUNITY SERVICES 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 is found not applicable,the report should explain the basis for the conclusion.
Note: Unless specifically documented, this report does not provide compliance to the International Residential
Code Sections R403.1.7 for foundations on or adjacent to slopes, Section R403.1.8 for expansive soils or section
1808.7.1 of the International Building Code Section for Foundations on or adjacent to slopes.
Applicant/Owner Final Vision Parcel# 12330-50-00092
Site Address XXX NE Larson Blvd
(1) (a) A discussion of general geologic conditions in the vicinity of the proposed development,
Located on page(s) 5
(b) A discussion of specific soil types,
Located on page(s) 6
(c) A discussion of ground water conditions,
Located on page(s) 7
(d) A discussion of the upslope geomorphology,
Located on page(s) 3
(e) A discussion of the location of upland waterbodies and wetlands,
Located on page(s) 3
(f) A discussion of history of landslide activity in the vicinity, as available in the referenced maps and
records.
Located on page(s) 8
(2) A site plan which identifies the important development and geologic features.
Located on Map(s) Site Plan—Appendix A
(3) Locations and logs of exploratory holes or probes.
Located on Map(s) Site Plan and Soil Logs(Appendix B)
(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) Site Plan
(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) Soil Profile(Appendix B)
(6) A description and results of slope stability analyses performed for both static and seismic loading
conditions.Analysis should examine worst case failures.The analysis should include the Simplified
Bishop's Method of Circles.The minimum static safety factor is 1.5,the minimum seismic safety
factor is 1.1,and the quasi-static analysis coefficients should be a value of 0.15.
Located on page(s) 9 Page 1 of37
7 a Appropriate restrictions on placement of drainage features
Located on page(s) 16
(b) Appropriate restrictions on placement of septic drain fields,
Located on page(s) 17
(c) Appropriate restrictions on placement of compacted fills and footings,
Located on page(s) 13- 15
(d) Recommended buffers from the landslide hazard areas shoreline bluffs and the tops of other slopes.
Located on page(s) 16
(e) Recommended setbacks from the landslide hazard areas shoreline bluffs and the tops of other slopes.
Located on page(s) 15
(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) 16
(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) 10
(10) An analysis of both on-site and off-site impacts of the proposed development.
Located on page(s) 12
(11) Specifications of final development conditions such as,vegetative management,drainage,erosion control, and
buffer widths.
Located on page(s) 17
(12) Recommendations for the preparation of structural mitigation or details of other proposed mitigation.
Located on page(s) 17
(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) Site Plan
I, Michael Staten, 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
PAL CLYDF Sr Report,dated December 21,2019,and entitled Final Vision
I&ASI,1(��� Single Family Residence, meets all the requirements of the
Mason County Resource Ordinance, Geologically Hazardous
Areas Section, is complete and true,that the assessment
'0P R 43045 demonstrates conclusively that the risks posed by the landslide
f sS�ovAL hazard can be mitigated through the included geotechnical
12/21/I design recommendations,and that all hazards are mitigated in
Disclaimer:Mason County does not such a manner as to prevent harm to property and public
certify the quality of the work done in health and safety.
this Geotechnical Report.
Page 2 of 2
TABLE OF CONTENTS
1.0 INTRODUCTION................................................................................................................................. 1
1.1 PROJECT INFORMATION.................................................................................................................... 1
1.2 PURPOSE OF INVESTIGATION AND SCOPE OF WORK........................................................................ 1
2.0 SURFACE CONDITIONS....................................................................................................................3
2.1 GENERAL OBSERVATIONS..................................................................................................................3
2.2 TOPOGRAPHY.....................................................................................................................................3
2.2.1 Upslope Geomorphology............................................................................................................3
23 SURFACE DRAINAGE..........................................................................................................................3
2.3.1 Upslope Water Bodies................................................................................................................3
2.4 SLOPE AND EROSION OBSERVATIONS...............................................................................................4
3.0 SUBSURFACE INVESTIGATION.....................................................................................................5
3.1 FIELD METHODS,SAMPLING AND FIELD TESTING...........................................................................5
3.2 GENERAL GEOLOGIC CONDITIONS................................................................................................... 5
3.3 SPECIFIC SUBSURFACE CONDITIONS................................................................................................. 7
3.3.1 Groundwater............................................................................................................................... 7
4.0 ENGINEERING ANALYSES AND CONCLUSIONS......................................................................8
4.1 SLOPE STABILITY...............................................................................................................................8
4.1.1 Slope Stability Analysis.............................................................................................................. 9
4.2 EROSION.............................................................................................................................................9
43 SEISMIC CONSIDERATIONS AND LIQUEFACTION..............................................................................10
4.3.1 Liquefaction..............................................................................................................................10
4.4 LANDSLIDE,EROSION AND SEISMIC HAZARDS CONCLUSIONS........................................................10
4.5 LATERAL EARTH PRESSURES...........................................................................................................10
4.6 ON-SITE AND OFF-SITE IMPACTS.....................................................................................................11
5.1 BUILDING FOUNDATION RECOMMENDATIONS.................................................................................12
5.1.1 Bearing Capacity.......................................................................................................................12
5.1.2 Settlement..................................................................................................................................13
5.1.3 Concrete Slabs-on-Grade..........................................................................................................13
5.2 EARTHWORK CONSTRUCTION RECOMMENDATIONS.......................................................................13
5.2.1 Excavation.................................................................................................................................13
5.2.2 Placement and Compaction of Native Soils and Engineered Fill...........................................14
5.2.3 Retaining Wall Backfill.............................................................................................................15
5.2.4 Wet Weather Considerations....................................................................................................15
5.2.5 Building Pads............................................................................................................................15
5.3 BUILDING AND FOOTING SETBACKS.................................................................................................16
5.4 SURFACE AND SUBSURFACE DRAINAGE...........................................................................................16
5.5 VEGETATION BUFFER AND CONSIDERATIONS.................................................................................16
5.6 TEMPORARY AND PERMANENT EROSION CONTROL.......................................................................16
5.7 SEPTIC DRAINFIELDS........................................................................................................................17
5.8 STRUCTURAL MITIGATION...............................................................................................................17
6.0 CLOSURE.............................................................................................................................................18
Appendix A-Site Plan
Appendix B-Soil Information
Appendix C-Slope Stability
Appendix D—Erosion Control
Appendix E—Drainage Details
1.0 INTRODUCTION
Envirotech Engineering (Envirotech) has completed a geotechnical investigation for a planned
single family residence located at XXX NE Larson Blvd, identified as parcel number 12330-50-
00092, Mason County, Washington. See the vicinity map on the following page for a general
depiction of the site location.
An initial geotechnical evaluation of the project was conducted by Envirotech on December 6,
2019. It was determined that slopes in excess of 40% with a vertical relief of at least 10 feet were
present within 300 feet of the planned development. Based on this site characteristic, the
proposed development will require a geotechnical report pursuant to Landslide Hazard Areas of
Mason County Resource Ordinance (MCRO) 17.01.100. During the site visit by Envirotech,
surface and subsurface conditions were assessed. After completion of the field work and
applicable project research, Envirotech prepared this geotechnical report which, at a minimum,
conforms to the applicable MCRO.
As presented herein, this report includes information pertaining to the project in this Introduction
Section; observations of the property and surrounding terrain in the Surface Conditions Section;
field methods and soil descriptions in the Subsurface Investigation Section; supporting
documentation with relation to slope stability, erosion, seismic considerations, and lateral earth
pressures in the Engineering Analyses and Conclusions Section; and, recommendations for
foundation, settlement, earthwork construction, retaining walls, erosion control, drainage, and
vegetation in the Engineering Recommendations Section.
1.1 Project Information
Information pertaining to the planned development of the project was provided by the proponent
of the property. The planned development consists of a I-or 2-story single family residence,new
on-site septic system, and other ancillary features typical of this type of development.
Approximate building footprint and other proposed features with relation to existing site
conditions are illustrated on the Site Map provided in Appendix A of this report.
1.2 Purpose of Investigation and Scope of Work
The purpose of this geotechnical investigation is to assess geological hazards, and evaluate the
project in order to provide geotechnical recommendations that should be implemented during
development. The investigation included characterizing the general project surface and
subsurface conditions, and evaluating the suitability of the soils to support the planned site
activities.
In order to fulfill the purpose of investigation, the geotechnical program completed for the
proposed improvements of the project include:
• Review project information provided by the project owner and/ or owner's
representative;
• Conduct a site visit to document the site conditions that may influence the construction
and performance of the proposed improvements of the project;
• Define general subsurface conditions of the site by observing subsoils within test pits
Envirotech Engineering Geotechnical Report
PO Box 984 page 1 Parcel 12330-50-00092
Belfair,Washington 98528 Mason County,Washington
Ph. 360-275-9374 December 21,2019
and/ or cut banks, review geological maps for the general area, research published
references concerning slope stability, and review water well reports from existing wells
near the project;
• Collect bulk samples,as applicable,at various depths and locations;
• Perform soils testing to determine selected index and/or engineering properties of the site
soils;
• Complete an engineering analysis supported by the planned site alterations, and the
surface and subsurface conditions that were identified by the field investigation, soil
testing,and applicable project research;and,
• Establish conclusions based on findings, and make recommendations for foundations,
drainage, slope stability, erosion control, earthwork construction requirements, and other
considerations.
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Vicinity Map from Mason County Website
Envirotech Engineering Geotechnical Report
PO Box 984 page 2 Parcel 12330-50-00092
Belfair,Washington 98528 Mason County,Washington
Ph. 360-275-9374 December 21,2019
2.0 SURFACE CONDITIONS
Information pertaining to the existing surface conditions for the project was gathered on
December 6, 2019 by a representative with Envirotech. During the site visit, the type of
geotechnical investigation was assessed, site features were documented that may influence
construction, and site features were examined that may be influenced by construction. This
Surface Conditions Section provides information on general observations, vegetation,
topography, drainage and observed slope/ erosion conditions for the project and surrounding
areas that may impact the project.
2.1 General Observations
Currently, the property is vacant. Vegetation on and near the project consists primarily of
secondary growth firs, madrona, blackberry, and other trees and shrubbery common to this area
of the Pacific Northwest. An aerial photo of the project and immediate vicinity is provided on the
following page.
2.2 Topography
The topographic information provided in this section was extrapolated from a public lidar source,
and incorporated observations and field measurements. Where necessary, slope verification
included measuring slope lengths and inclinations with a cloth tape and inclinometer. See the Site
Plan in Appendix A in this report for an illustration of general topography with respect to the
planned development.
Critical ascending slopes,with grades exceeding 40% appear to be within 300 feet of the planned
development.The maximum critical slope is approximately 60% with a vertical relief of about 30
feet.
Descending grades are generally located to the south of the planned development. These slopes
average 30%within 300 feet of the project.
2.2.1 Upslope Geomorphology
The upland area of the property and beyond is generally situated on a hillside of glacial
origin.
2.3 Surface Drainage
Runoff originating upslope of the development is mostly diverted away from the property by
accommodating topography. Excessive scour, erosion or other indications of past drainage
problems were not observed within the immediate vicinity of the planned development.
2.3.1 Upslope Water Bodies
There are no apparent water bodies or wetlands located upslope from the planned
development that would significantly influence the project.
Envirotech Engineering Geotechnical Report
PO Box 984 page 3 Parcel 12330-50-00092
Belfair,Washington 98528 Mason County,Washington
Ph. 360-275-9374 December 21,2019
2.4 Slope and Erosion Observations
The slope gradients near the project signal a potential landslide or erosion hazard area. Some
indicators that may suggest past slope movements include:
• Outwash of sediments near the bottom of the slope,
• Fissures, tension cracks, hummocky ground or stepped land masses on the face or top of
the slope,and parallel to the slope,
• Fine,saturated subsurface soils,
• Old landslide debris,
• Significant bowing or leaning trees,or,
• Slope sloughing or calving.
These slope instability indicators or other significant mass wasting on the property or within the
general vicinity of the project were not observed or discovered during research. Indications of
past landslides, current unstable slopes, deep-seated slope problems, or surficial slope failures
were not observed during the site visit.
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Aerial Photo from Mason County Website
Envirotech Engineering Geotechnical Report
PO Box 984 page 4 Parcel 12330-50-00092
Belfair,Washington 98528 Mason County,Washington
Ph. 360-275-9374 December 21,2019
3.0 SUBSURFACE INVESTIGATION
Information on subsurface conditions pertaining to the project was primarily gathered on
December 6, 2019 by a representative with Envirotech. Applicable information on field methods,
sampling, field testing, general geologic conditions, specific subsurface conditions, and results
from soil testing are presented in this section of the report. Appendix B of this report includes
pertinent information on subsurface conditions for the project, such as subsoil cross-section(s),
test pit log(s), and applicable water well report(s). Water well reports were utilized to estimate
ground water levels, and if sufficient, were used in identifying subsoil types. Applicable test pit
locations are depicted on the Site Plan provided in the appendix of this report.
3.1 Field Methods,Sampling and Field Testing
Information on subsurface conditions for the project was accomplished by examining soils within
test pits and/ or nearby banks extending to depths of up to 6 feet below the natural ground
surface. Information on subsurface conditions also included reviewing geological maps
representing the general vicinity of the project, and water well reports originating from nearby
properties.
Soil samples were not obtained from this project. Envirotech measured the relative density of the
near-surface in-situ soils by gauging the resistance of hand tools. Within testing locations, field
testing results generally indicated loose to medium dense soils in the upper 48 inches, and very
dense soils from 48 inches to the depth of terminus.
3.2 General Geologic Conditions
In general, soils at the project are composed of materials from glacial advances. The geologic
conditions as presented in the "Geologic Map of Washington," compiled by J. Eric Schuster,
2002 indicates Quaternary sediments, Qg. Quaternary sediments are generally unconsolidated
deposits, and dominantly deposited from glacial drift,including alluvium deposits.This project is
located within the Puget Lowland. Typically, "lower tertiary sedimentary rocks unconformably
overlie the Crescent Formation"as revealed in the Geologic Map. Initial sedimentary rocks were
formed from shales, sandstones and coal deposits from rivers. During the Quaternary period, the
Puget Lowland was covered by numerous ice sheets,with the most recent being the Fraser glacier
with a peak of approximately 14,000 years ago. Upon the glacial retreat, the landscape was
formed by glacial erosion glacial drift deposits.
The "Geologic Map of the Belfair 7.5-minute Quadrangle, Mason, Kitsap and Pierce Counties,
Washington'by Michael Polenz, Katelin Alldritt, Nicholas J. Heheman, Isablle Y. Sarikhan, and
Robert L.Logan,July 2009,provides the following caption(s)for the project area:
Envirotech Engineering Geotechnical Report
PO Box 984 page 5 Parcel 12330-50-00092
Belfair,Washington 98528 Mason County,Washington
Ph. 360-275-9374 December 21,2019
Vashou glacial ice-contact deposits—Sand,gravel,lodgment till.and
flow till,uunor silt and clay beds,tan to gray,variably sorted;loose to
compact;massive to well stratified;locally includes over-steepened beds
that typically reflect sub-ice flow.bW their dip may,along with
mall-scale shears,also have developed as collapse features or due to
gtaciotectonic and tectonic deforutation,formed in the presence of
meltwater alongside ice,generally toward the end of the glaciation,and is
thus comnonly accompanied by stagnant-ice features,such as kettles and
less-orderly huumwcky topography.eskers(also separately mapped as
sullut ut Qge),and subglactal or subaenal outwash channels Deposits and
norphologies that support conceptual association with both ice and
meltwater are common in the nap area and suggest that where unit Qgic is
mapped to the presence of fluted topography.it is conuuonly only a few
feet thick and locally could have been mapped as undifferentiated drift
(unit Qgd).Elsewhere,the utut may be over 100 it duck,Unit Qgtc also
includes poorly consolidated till conuuonly accompanied by underlying.
angular sand and noted as"sub-glacially reworked till'•by Laprade(2003)
(see Geologic setting).especially in fluted areas that lack dead-ice
features.See unit Qgo and Fig.4 for discussion of siuulanties between
to uts Qgic and Qgo(and its subtuuts Qgos.Qgof•acid Qgol).A
discrepancy between this snap and the Vaughn quadrangle to the south
resulted where Logan and Walsh(2007)napped undifferentiated
Quaternary deposits(taut Qu)because they lacked field exposures and
geomorphic signs of the dead-ice deposits that are apparent north of the
boundary.Dead-ice topography north of the boundary also reveals a sandy
deposit napped as unit Qgos by Logan mid Walsh(2007)to be a facies
within taut Qgic.Locally divided into
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Envirotech Engineering Geotechnical Report
PO Box 984 page 6 Parcel 12330-50-00092
Belfair,Washington 98528 Mason County,Washington
Ph. 360-275-9374 December 21,2019
3.3 Specific Subsurface Conditions
The following subsurface conditions are estimated descriptions of the project subgrade utilizing
information from the depth of penetration at all testing, sampling, observed and investigated
locations. Soils for this project were primarily described utilizing the Unified Soil Classification
System(USCS)and the Soil Conservation Service(SCS)descriptions.
The project is currently composed of native soils without indications of fill. Within test pit
locations, soils within the upper 6 feet of natural ground were generally observed to be poorly
graded sand (SP). These soils may extend to depths greater than 50 feet. This is based on nearby
well reports,site geology,and/or knowledge of the general area.
The relative densities of the soil within selected test pits are provided above in Section 3.1.
Expanded and specific subsurface descriptions, other than what is provided in this section, are
provided in the soil logs located in Appendix B of this report.
According to the "Soil Survey of Mason County," by the United States Department of
Agriculture, Soil Conservation Service, the site soils are described as Everett Gravelly Loamy
Sand, Eef with 5% - 15% slopes. The soil designations are depicted in the aerial photograph
below,and descriptions are provided in Appendix B of this report.
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Soil Survey From USDA Natural Resources Conservation Service
3.3.1 Groundwater
From the water well report(s)and knowledge of the general area, permanent groundwater
is at least 100 feet directly below the property at the building pad location. Surface
seepage or perched groundwater at shallow depths was not observed on-site, nor
indicated on the well reports.
Envirotech Engineering Geotechnical Report
PO Box 984 page 7 Parcel 12330-50-00092
Belfair,Washington 98528 Mason County,Washington
Ph. 360-275-9374 December 21,2019
4.0 ENGINEERING ANALYSES AND CONCLUSIONS
The following section includes slope stability, erosion, seismic considerations, and impacts to
both on-site and off-site properties.
4.1 Slope Stability
Landslides are natural geologic processes, and structures near slopes possess an inherent risk of
adverse settlement, sliding or structural damage due to these processes. Geotechnical engineering
cannot eliminate these risks for any site with sloping grades because gravity is constantly
inducing strain on the sloping soil mass. Excessive wet weather and/ or earthquakes will
exacerbate these strains. Geotechnical engineering considers excessive wet weather and `design'
earthquakes in order to provide an acceptable factor of safety for developing on or near sloping
terrain with relation to current engineering protocol. These factors of safeties are based on
engineering standards such as defining engineering properties of the soil, topography, water
conditions, seismic acceleration and surcharges. Surface sloughing or other types of surficial
slope movements usually do not affect the deep-seated structural capability of the slope.
However, repeated surficial slope movements, if not repaired, may present a threat to the
structural integrity of the slope. If any slope movement arises,the slope should be inspected by an
engineer. Subsequently,maintenance may be required in order to prevent the possibility of further
surficial or deep seated slope movements that may be damaging to life and property.
According to the Resource Map from the Washington State Department of Natural Resources
(DNR), the project is not within terrain labeled `highly unstable' relating to soils. DNR labeled
portions of this project as medium and high slope instability with relation to slopes. A Resource
Map from the DNR Forest Practices Application Review System is provided below:
n . . p
E IN Project
sit
Soils
■ Hydnc sods
■ ,r o' Highly Unstable
NE
Erodible
No Data
_ No Data or Gravel Pots
Slope Stability-West
® Moderate Slope Instability
d 50 100R
1:2,257 N � � .High Slope Instability
r
Resource Map from Washington State Department of Natural Resources Website
Envirotech Engineering Geotechnical Report
PO Box 984 page 8 Parcel 12330-50-00092
Belfair,Washington 98528 Mason County,Washington
Ph. 360-275-9374 December 21,2019
4.1.1 Slope Stability Analysis
The Simplified Bishop Method, utilizing `STABLE' software, was used to analyze the
static stability of the site slopes. Seismic conditions were estimated utilizing worst case
scenario values from the static analysis,a quasi-static analysis coefficient of at least 0.15,
and applying the applicable values to STABLE software. Various radii's and center
points of the circle were automatically selected, and produced factor of safeties in a
graphical and tabular format. Worst case scenario values were used in the slope stability
analysis in regards to topography, surcharges, water content, internal friction and
cohesion of the site soils. STABLE software has been repeatedly checked with manual
calculations, and consistently proved to be a very conservative program. The following
soil properties were used in the analysis, and are based on observed conditions, known
geology, and/or published parameters:
Soil unit weight: 100 pcf
Angle of internal friction: 34 degrees
Cohesion: 0 psf
Based on the slope stability analysis, unacceptable factors of safety could be present on
and near the critical slope,but do not reflect conditions where development is expected to
occur. For this project, at the location of the proposed development, minimum factor of
safeties for static and dynamic conditions were estimated to be at least 1.5 and 1.1,
respectively. See the slope stability information in Appendix C for a depiction of
minimum factors of safety away from the project.
4.2 Erosion
Based on the USCS description of the project soils, the surface soils are considered moderately
erodible. According to the Resource Map from the Washington State DNR, as provided above,
the project is not within terrain labeled `highly erodible.' This project is not within an erosion
hazard area as defined by the MCRO. Erosion hazard areas are those with USDA SCS
designations of River Wash (Ra), Coastal Beaches (Cg), Alderwood Gravelly Sandy Loam on
slopes 15% or greater (Ac and Ad), Cloquallum Silt Loam on slopes 15% or greater (Cd),
Harstine Gravelly Sandy Loam on slopes 15% or greater (Hb), and Kitsap Silt Loam on slopes
15%or greater(Kc).
It is our opinion that minor erosion control recommendations provided in this report is sufficient
for the development of this project, and additional engineered erosion control plans are not
required. Temporary and permanent erosion control measures are required for site development.
Extents of temporary erosion control will mostly depend on the timeliness of construction,
moisture content of the soil,and amount of rainfall during construction. Soil erosion typical to the
existing site conditions and planned disturbance of the project include wind-borne silts during dry
weather, and sediment transport during prolonged wet weather. Sediment transport could be from
stormwater runoff or tracking off-site with construction equipment.
The Temporary and Permanent Erosion Control Section (Section 5.6) of this report consist of
specific erosion controls to be implemented. Additional erosion control information and
specifications may be found in the latest addition of the "Stormwater Management Manual for
Envirotech Engineering Geotechnical Report
PO Box 984 page 9 Parcel 12330-50-00092
Belfair,Washington 98528 Mason County,Washington
Ph. 360-275-9374 December 21,2019
Western Washington," prepared by the Washington State Department of Ecology Water Quality
Program.
4.3 Seismic Considerations and Liquefaction
There are no known faults beneath this project. The nearest Class `A' or Class `B' fault to this
property is the Tacoma Fault Zone, which is approximately 2 miles to the south of this project.
This information is based on the USGS Quaternary Fault and Fold Database for the United States.
Potential landslides due to seismic hazards have been considered, and are addressed in the Slope
Stability Analysis Section provided earlier in this report.
Soils immediately below the expected foundation depth for this project are generally Type D,
corresponding to the International Building Code (IBC) soil profiles. According to the IBC, the
regional seismic zone is 3 for this project. The estimated peak ground acceleration ranges from
0.50g to 0.60g.This estimation is based on the United States Geological Survey(USGS)National
Seismic Hazard project in which there is an estimated 2% probability of exceedance within the
next 50 years.
4.3.1 Liquefaction
The potential for liquefaction is believed to be low for this project. This is based,in part,
on the subsurface conditions such as soil characteristics and the lack of a permanent
shallow water table. Subgrade characteristics that particularly contribute to problems
caused from liquefaction include submerged, confined, poorly-graded granular soils (i.e.
gravel, sand,silt). Although gravel-and silt-sized soil particles could be problematic,fine
and medium grained sands are typically subjected to these types of seismic hazards. No
significant saturated sand stratifications are anticipated to be within the upper 50 feet of
the subsoil for this project.
4.4 Landslide,Erosion and Seismic Hazards Conclusions
DNR indicated historic landslide activity near the project.Mapped slope conditions,as delineated
by the Departments of Ecology and/or Natural Resources, were considered in our slope stability
assessment. Based on the proximity and severity of mapped delineations with respect to the
proposed development, results of the aforesaid slope stability analysis, observed surface
conditions, and other pertinent information, it is our opinion that the proposed development may
occur in accordance with the recommendations m s geotec c report.
4.5 Lateral Earth Pressures
Retaining walls may be utilized for this project. The lateral earth pressures exerted through the
backfill of a retaining wall are dependent upon several factors including height of retained soil
behind the wall, type of soil that is retained, degree of backfill compaction, slope of backfill,
surcharges,hydrostatic pressures,earthquake pressures,and the direction and distance that the top
of the wall moves. A structural or geotechnical professional should design retaining walls based
on specific conditions.
Envirotech Engineering Geotechnical Report
PO Box 984 page 10 Parcel 12330-50-00092
Belfair,Washington 98528 Mason County,Washington
Ph. 360-275-9374 December 21,2019
Soil parameters for the structural design of retaining walls may be estimated as 134 pounds per
cubic foot (pcf) and 110 pcf for engineered fill and native soils, respectively. The angle of
internal friction may be estimated as 36 degrees and 34 degrees for engineered fill and native
soils, respectively. These soil parameters are based on soil type and placement conforming to the
Earthwork Construction Recommendations Section in this report.
4.6 On-Site and Off-Site Impacts
From a geotechnical position, it is Envirotech's opinion that the subject property and adjacent
properties to the proposed development should not be significantly impacted if all
recommendations in this report are followed. This opinion is based on the expected site
eve opment, existing topography, existing nearby development, land cover, and adhering to the
recommendations presented in this report. Future development or land disturbing activities on
neighboring properties or properties beyond adjacent parcels that are upslope and/or downslope
from the subject property could cause problems to the subject property. For this reason, future
development or land disturbance near the subject property should be evaluated by a geotechnical
engineer.
Envirotech Engineering Geotechnical Report
PO Box 984 page 11 Parcel 12330-50-00092
Belfair,Washington 98528 Mason County,Washington
Ph. 360-275-9374 December 21,2019
5.0 ENGINEERING RECOMMENDATIONS
The following sections present engineering recommendations for the proposed improvements of
the project. These recommendations have been made available based on the planned
improvements as outlined in the Introduction Section of this report; general observations
including drainage and topography as recapitulated in the Surface Conditions Section; soil/
geologic conditions that were identified from the geotechnical investigation that is summarized in
the Subsurface Investigation Section; and, project research, analyses and conclusions as
determined in the Engineering Analysis and Conclusions Section. Recommendations for the
project that is provided herein, includes pertinent information for building foundations,earthwork
construction, building and/ or footing setbacks, drainage, vegetation considerations, and erosion
control.
5.1 Building Foundation Recommendations
Recommendations provided in this section account for the site development of a typical one- or
two-story, single family residential structure. The recommended allowable bearing capacities and
settlements as presented below, consider the probable type of construction as well as the field
investigation results by implementing practical engineering judgment within published
engineering standards. Evaluations include classifying site soils based on observed field
conditions and soil testing for this project. After deriving conservative relative densities, unit
weights and angles of internal friction of the in-situ soils, the Terzhagi ultimate bearing capacity
equation was utilized for determining foundation width and depth. Foundation parameters
provided herein account for typical structural pressures due to the planned type of development.
A structural analysis is beyond the scope of a geotechnical report, and a structural engineer may
be required to design specific foundations and other structural elements based on the soil
investigation. Stepped foundations are acceptable, if warranted for this project. Continuous,
isolated, or stepped foundations shall be horizontally level between the bottom of the foundation
and the top of the bearing strata. The frost penetration depth is not expected to extend beyond 12
inches below the ground surface for this project under normal circumstances and anticipated
design features.
5.1.1 Bearing Capacity
Existing in-situ soils for this project indicates that the structure can be established on
shallow, continuous or isolated footings. Foundations shall be established on relatively
undisturbed native soil that is competent and unyielding. Alternatively, foundations may
be constructed on selective re-compacted native soil or compacted engineered fill as
described in the Earthwork Construction Recommendations Section of this report.
For a bearing capacity requirement of no more than 1500 psf, a minimum continuous
footing width of 15 inches shall be placed at a minimum of 12 inches below the existing
ground surface atop unyielding soils. For a columnar load of no more than 3 tons, a
circular or square isolated foundation diameter or width shall be at least 24 inches.
If step foundations are utilized, the downhill side of the home shall have a foundation
depth of at least 2 feet from the top of existing ground surface to the bottom of the
footing on the downslope side of the foundation. If basements are planned or the home is
Envirotech Engineering Geotechnical Report
PO Box 984 page 12 Parcel 12330-50-00092
Belfair,Washington 98528 Mason County,Washington
Ph. 360-275-9374 December 21,2019
otherwise benched into the hillside, standard foundation depths are permissible.
Foundation recommendations are made available based on adherence to the remaining
recommendations that are provided in this report. Alterations to the aforementioned
foundation recommendations may be completed upon a site inspection by a geotechnical
engineer after the foundation excavation is completed.
5.1.2 Settlement
Total and differential settlement that a structure will undergo depends primarily on the
subsurface conditions, type of structure, amount and duration of pressure exerted by the
structure, reduction of pore water pressure, and in some instances, the infiltration of free
moisture. Based on the expected native soil conditions, anticipated development, and
construction abides by the recommendations in this report, the assumed foundation
system may undergo a maximum of 1.0 inch total settlement,and a maximum differential
settlement of 0.75 inch.
5.1.3 Concrete Slabs-on-Grade
Interior slabs, if utilized, should be supported on a minimum of 4 inches of compacted
coarse, granular material (Retained on U.S. Sieve #10 or greater) that is placed over
undisturbed, competent native subgrade or engineered fill per the Earthwork
Recommendations Section below.
The recommendations for interior concrete slabs-on-grade as presented herein are only
relevant for the geotechnical application of this project. Although beyond the scope of
this report, concrete slabs should also be designed for structural integrity and
environmental reliability. This includes vapor barriers or moisture control for mitigating
excessive moisture in the building.
5.2 Earthwork Construction Recommendations
Founding material for building foundations shall consist of undisturbed native soils to the
specified foundation depths. Compacted engineered fill, or selective re-compacted native soils
may be used to the extents provided in this Earthwork Construction Recommendations Section.
The following recommendations include excavations, subgrade preparation, type of fill, and
placement of fill for building foundations.
5.2.1 Excavation
Excavation is recommended to remove any excessive organic content or other deleterious
material, if present, beneath foundations and to achieve appropriate foundation depth.
Additional sub-excavation will be required for this project if the soils below the required
foundation depth are loose, saturated, not as described in this report, or otherwise
incompetent due to inappropriate land disturbing, or excessive water trapped within
foundation excavations prior to foundation construction.All soils below the bottom of the
excavation shall be competent, and relatively undisturbed or properly compacted fill. If
these soils are disturbed or deemed incompetent, re-compaction of these soils below the
anticipated footing depth is necessary. Excavations shall be completely dewatered,
Envirotech Engineering Geotechnical Report
PO Box 984 page 13 Parcel 12330-50-00092
Belfair,Washington 98528 Mason County,Washington
Ph. 360-275-9374 December 21,2019
compacted, and suitable before placement of additional native soil, engineered fill or
structural concrete.
5.2.2 Placement and Compaction of Native Soils and Engineered Fill
For engineered fill or disturbed native soils that will be utilized as fill material directly
beneath foundations, observation and/ or geotechnical testing is required prior to
foundation construction. The following placement and compaction requirements are
necessary.
For disturbed native soils or engineered fill beneath foundations, limits of compacted or
re-compacted fill shall extend laterally from the bottom edge of the foundation at a rate of
one horizontal foot for each foot of compacted or re-compacted fill depth beneath the
foundation. See the illustration below.
FOOTING
COMPACTED
NATIVE SOILS
OR ENGINEERED t
FILL. 1
_71 U.VLt:S7URBE� SUBGR !
Both engineered fill and native soils used as compacted fill should be free of roots and
other organics, rocks over 6 inches in size, or any other deleterious matter. Because of
moisture sensitivity, importing and compacting engineered fill may be more economical
than compacting disturbed native soils. Engineered fill shall include having the soils
retained on the No. 4 sieve crushed (angular), and should consist of the following
gradation:
U.S. Standard Sieve %Finer(by weight)
6" 100
Y 60— 100
No.4 20—60
No.200 0-8
Table 1
Particle Size Distribution of Engineered Fill
Compaction shall be achieved in compacted lifts not to exceed 6 inches for both native
soils and engineered fill,respectively.Each lift should be uniformly compacted to at least
95% of the modified Proctor maximum dry density (ASTM D 1557) and within 3% of
optimum moisture content. Each lift surface should be adequately maintained during
construction in order to achieve acceptable compaction and inter-lift bonding.
Temporary earth cuts and temporary fill slopes exceeding 4 feet in height should be
limited to a slope of 2:1 (horizontal:vertical). Utility trenches or other confined
excavations exceeding 4 feet should conform to OSHA safety regulations. Permanent cut
Envirotech Engineering Geotechnical Report
PO Box 984 page 14 Parcel 12330-50-00092
Belfair,Washington 98528 Mason County,Washington
Ph. 360-275-9374 December 21,2019
and fill slopes shall be limited to a slope of 2:1, unless otherwise approved by an
engineer.
5.2.3 Retaining Wall Backfill
Native soils may be used as retaining wall backfill for this project if the total wall height
is 4 feet or less and the recommendations below are followed. Native soils for retaining
walls exceeding 4 feet in height must be approved by the local authority or evaluated by
an engineer. Backfill may consist of engineered fill,as presented in this report,or borrow
material approved by a geotechnical engineer. Compaction of these materials shall be
achieved in compacted lifts of about 12 inches. Each lift should be uniformly compacted
to at least 85%, and no more than 90% of the modified Proctor maximum dry density
(ASTM D 1557).If pavement or building loads are planned to be located within retaining
wall backfill, then 90% compaction is required. In addition, heavy construction
equipment should be at a distance of at least '/2 the wall height. Over-compaction and
limiting heavy construction equipment should be prevented to minimize the risk of excess
lateral earth pressure on the retaining structure. Envirotech recommends that retaining
wall backfill is compacted with light equipment such as a hand-held power tamper. If
clean, coarse gravel soils are utilized as engineered fill, and surcharges will not influence
the retaining wall, compaction may be achieved by reasonably densifying granular soils
with construction equipment.
5.2.4 Wet Weather Considerations
Due to the types of subsurface soils, additional provisions may be required during
prolonged wet weather. Every precaution should be made in order to prevent free
moisture from saturating the soils within excavations. If the bottom of excavations used
for footing placement changes from a moist and dense/hard characteristic as presented in
this report to muck or soft, saturated conditions, then these soils become unsuitable for
foundation bearing material. If this situation occurs, a geotechnical engineer should be
notified, and these soils should be completely removed and replaced with compacted
engineered fill or suitable native material as presented in this section.
5.2.5 Building Pads
Building pads for this project, if utilized, shall be constructed per the fill placement and
compaction recommendations as presented above. Both engineered fill and native soils
may be used for building pads. Building pad slopes shall be no steeper than 2:1 for both
compacted engineered fill and re-compacted native soils used as fill. Building pad fill
shall be"keyed"into the existing subgrade to a depth of at least 2 feet below the existing
ground surface. The term "keyed," as used here, implies that the interface between the
building pad and subgrade is horizontally level. Alternatively, building pads may be
keyed into the subgrade to the above specified depth, and stepped. Stepped fill should be
keyed into the subgrade at a minimum bench width of 8 feet. All footings shall be
located at least 5 feet away from the top of the engineered fill slope.
Envirotech Engineering Geotechnical Report
PO Box 984 page 15 Parcel 12330-50-00092
Belfair,Washington 98528 Mason County,Washington
Ph. 360-275-9374 December 21,2019
5.3 Building and Footing Setbacks
Due to potential debris flow, the building location should have a minimum setback from
the local ascending slope toe equal to '/z the slope height. The toe of the ascending slope
is delineated as a grade break in which the ascending slope is in excess of 40%.
Envirotech recommends the building setback to be at least 15 feet from the toe of the
nearby ascending slope. See the Site Plan in Appendix A for an illustration of the
setbacks.
5.4 Surface and Subsurface Drainage
Positive drainage should be provided in the final design for all planned residential buildings.
Drainage shall include sloping the ground surface, driveways and sidewalks away from the
project structures. All constructed surface and subsurface drains should be adequately maintained
during the life of the structure. If drainage problems occur during or after construction, additional
engineered water mitigation will be required immediately. This may include a combination of
swales,berms,drain pipes,infiltration facilities,or outlet protection in order to divert water away
from the structures to an appropriate protected discharge area. Leakage of water pipes, both
drainage and supply lines, shall be prevented at all times.
If impervious thresholds are exceeded per the prevailing agency code, then engineered
stormwater management plans are required for this project. The drainage engineer must
coordinate with a geotechnical engineer for input with relation to slope stability prior to
submitting drainage plans. If stormwater management plans are not required for this project,then
the following recommendations should be followed.
For this project, we recommend that infiltration is avoided in order to maintain slope stability,
and that roof downspout dispersion on splash blocks are employed. Recommended drainage
details are provided in Appendix E of this report.
5.5 Vegetation Buffer and Considerations
For this project, we believe that a detailed clearing and grading plan is not warranted unless the
prevailing agency thresholds are exceeded, and basic vegetation management practices should be
adhered to.
Vegetation Buffer—Vegetation shall not be removed from the face of the critical slope.However,
any tree deemed hazardous to life or property shall be removed. If tree removal is necessary,then
stumps and roots shall remain in place, and the underbrush and soil shall remain undisturbed as
much as possible. Any disturbed soil shall be graded and re-compacted in order to restore the
terrain similar to preexisting conditions and drainage patterns. See the Site Plan in Appendix A of
this report for a depiction of the vegetation buffer.
5.6 Temporary and Permanent Erosion Control
Erosion control during construction should include minimizing the removal of vegetation to the
least extent possible. Erosion control measures during construction may include stockpiling
cleared vegetation, silt fencing, intercepting swales, berms, straw bales, plastic cover or other
Envirotech Engineering Geotechnical Report
PO Box 984 page 16 Parcel 12330-50-00092
Belfair,Washington 98528 Mason County,Washington
Ph. 360-275-9374 December 21,2019
standard controls. Although other controls may be used, if adequate, silt fencing is presented in
this report as the first choice for temporary erosion control. Any erosion control should be located
down-slope and beyond the limits of construction and clearing of vegetation where surface water
is expected to flow. If the loss of sediments appears to be greater than expected, or erosion
control measures are not functioning as needed, additional measures must be implemented
immediately. See Appendix D for sketches and general notes regarding selected erosion control
measures. The Site Plan in Appendix A depicts the recommended locations for erosion control
facilities to be installed as necessary.
Permanent erosion control is necessary if substantial vegetation has not been established within
disturbed areas upon completion of the project.Temporary erosion control should remain in place
until permanent erosion control has been established. Permanent erosion control may include
promoting the growth of vegetation within the exposed areas by mulching, seeding or an
equivalent measure. Selected recommendations for permanent erosion control are provided in
Appendix D. Additional erosion control measures that should be performed include routine
maintenance and replacement, when necessary, of permanent erosion control, vegetation,
drainage structures and/or features.
5.7 Septic Drainfields
Septic drainfields were considered in our geotechnical evaluation.This includes septic drainfields
with relation to the observed soil conditions, expected vegetation removal, and existing and
proposed topography. Based on the aforesaid parameters, the septic drainfields are not expected
to adversely influence critical slopes.This is also based on compliance with all recommendations
in this report.
5.8 Structural Mitigation
With respect to landslide alleviation or slope improvements, structural mitigation is not necessary
for this project. This determination is based on the anticipated improvements of the project,
engineering conclusions,and compliance with all recommendations provided in this report.
Envirotech Engineering Geotechnical Report
PO Box 984 page 17 Parcel 12330-50-00092
Belfair,Washington 98528 Mason County,Washington
Ph. 360-275-9374 December 21,2019
6.0 CLOSURE
Based on the project information provided by the owner, the proposed development, and site
conditions as presented in this report, it is Envirotech's opinion that additional geotechnical
studies are not required to further evaluate this project.
Due to the inherent natural variations of the soil stratification and the nature of the geotechnical
subsurface exploration, there is always a possibility that soil conditions encountered during
construction are different than those described in this report. It is not recommended that a
qualified engineer performs a site inspection during earthwork construction unless fill soils will
influence the impending foundation. However, if native,undisturbed subsurface conditions found
on-site are not as presented in this report,then a geotechnical engineer should be consulted.
This report presents geotechnical design guidelines, and is intended only for the owner, or
owners' representative, and location of project described herein.This report should not be used to
dictate construction procedures or relieve the contractor of his responsibility.
Any and all content of this geotechnical report is only valid in conjunction with the compliance of
all recommendations provided in this report. Semantics throughout this report such as `shall,'
`should' and `recommended' imply that the correlating design and/or specifications must be
adhered to in order to potentially protect life and/or property. Semantics such as `suggested' or
`optional' refer that the associated design or specification may or may not be performed, but is
provided for optimal performance. The recommendations provided in this report are valid for the
proposed development at the issuance date of this report. Changes to the site other than the
expected development, changes to neighboring properties, changes to ordinances or regulatory
codes, or broadening of accepted geotechnical standards may affect the long-term conclusions
and recommendations of this report.
The services described in this report were prepared under the responsible charge of Michael
Staten, a professional engineer with Envirotech. Michael Staten has appropriate education and
experience in the field of geotechnical engineering in order to assess landslide hazards,
earthquake hazards,and general soil mechanics.
Please contact Michael Staten at 360-275-9374 if you have any questions, comments, or require
additional information.
Sincerely,
Envirotech Engineering
Jessica Legarza,M.S. Michael Staten,P.E.r(,
Staff Geologist Geotechnical Engineer
Envirotech Engineering Geotechnical Report
PO Box 984 page 18 Parcel 12330-50-00092
Belfair,Washington 98528 Mason County,Washington
Ph. 360-275-9374 December 21,2019
APPENDIX A
SITE PLAN
SCALE 1 INCH - 80 FEET
0 20 40 80
APPROXIMATE TOP OF SLOPE
EXCEEDING 40%
APPROXIMATE TOE OF SLOPE
EXCEEDING 40%
6
15 FT CONSTRUCTION
SETBACK FROM TOE 13F
CRITICAL SLOPE
2A0 �•
\X
2� _`� / �• / BUILDABLE AREA
I y�
TPI
�I I
I
I I
16•t I
I r�+
le
1 +,
+
�P 8
OPERTY LINE
A49T LtwTlvn 1V- EV PIDWU Pk flag*T'&6fKQ'-Lm:Al P;n �]rif,L� �:+��T�� RESIDENCE
:*:V-4;?Et. W4-1:�L:r nrAT.v rs MA)A en111LU -4 E41" aHE-a IN THE GE❑TECHNICAL REPORT
is'-Diq-UU ft F.`WOIti-.
�.:��4'WWE L-T7iQ ClOi W46'pRE2 7"f A 1-1fX71
2[G LAMB SUliv'C`tiM, i•f.JRL ~_t-1 INC
CONTOURS WERE EXTRAPOLATED FROM A PUBLIC LIDAR SOURCE, AND XXX LARSEN BLVD
INCORPORATED FIELD MEASUREMENTS AS EXPLAINED 1N THE GEOTECHNICAL LEGEND PARCEL 12330-50-00092
REPORT. MASON COUNTY, WASHINGTON
3, BOUNDARIES WERE NOT PREPARED BY A LICENSED SURVEYOR. LOCATIONS TEMPORARY ENGINEER
OF SITE FEATURES THAT ARE SHOWN HERE, SUCH AS TOP W SLOPES, TIE +++EROSION CDNTRDL ENVIROTECH ENGINEERING
OF SLOOPES,WATER FEATURES, ETC.., WITH RELATION TO THE PROPERTY PO BOX-04
Ltd AAT ZE VEW=V THC 0010L KC=0ftT=S IN THE NO IM F: ABOD'AnU BkL1"AYt,KArKOW'10N WAW
"mr::3 ww-Mi]�w PWVIW Q�X1H1'ym 1CrC.w1w
0:I ATLUi TU MMUgr PRAT116'A. T FlOW"LV THIR 3 +'wry++* CUML iA %6 97%R,OFi
MATUM Y x►,DCAA"M OM TNL iJUW FROM IV 0R=240exa TtRr PtT S=TE PLAN
APPENDIX B
SOIL INFORMATION
vENTICAL AM HO IZ04TAL sEALE-
I VCH N FEET
�M
EXISTING
GRADE
NE LARS❑N
BLVD
SSA PR❑POSED
HMSE
MEDIUM DENSE TO DENSE
POORLY GRADED SAND (SP)
SECTION A-A
N1�.gi.Tl OVHER/ LOCATIIlw
Sly ,-- FAMILY RESIDENCE
GEOTECHNICAL REPORT
FDP-V2EN DC
NOTES- aW Y ON
)) MINOR GRADE CHANGES REOLGRED IN ORDER TO ACHIEVE QWaMEW D4WEERINC
POSITIVE DRAINAGE
2) THE SOIL PROFILE IS ACCURATE FOR THE DEPTH OF P )i!N<TON 98529
04
THE ODSERVED TEST PITS AT THE SPECIFIED LOCATIONS.
LOVER KPT14S ARE RASED ON SITE GEOLOGY,
WELL LMS),AND/OR EXPERIENCE IN THE GENERAL AREA.
SOIL PROFILE
TEST PIT LOG
TEST PIT NUMBER TP-1
PROJECT: Final Vision Geotechnical Report DATE OF LOG: 12/06/2019
PROJECT NO: 19238 LOGGED BY: RJM
CLIENT: Final Vision Inc EXCAVATOR: N/A
LOCATION: XXX NE Larson Blvd DRILL RIG: None
Mason County,Washington ELEVATION: N/A
INITIAL DEPTH OF WATER: WA FINAL DEPTH OF WATER: N/A
SOIL STRATA, STANDARD PENETRATION TEST
DEPTH SAMPLERS USCS DESCRIPTION LL PI CURVE
AND TEST DATA DEPTH N 10 30 50
0
SP Poorty graded SAND
1
2
3
4
5
6
Excavation terminated at approximately 6
feet
7
8
9
10
No Groundwater Encountered ENVIROTECH ENGINEERING
Thn Mvmsbon pertans orgy to tns boring and snarl not be Geotechnical Engineering
lnfirpek d as being mdia6ve of the entire m*
Map Unit Description:Everett gravelly loamy sand,5 to 15 percent slopes---Mason County.
Washington
Mason County, Washington
Ee—Everett gravelly loamy sand, 5 to 15 percent slopes
Map Unit Setting
National map unit symbol. 2hk7
Elevation 50 to 500 feet
Mean annual precipitatiwl 55 to 90 inches
Mean annual air temperature_ 48 to 50 degrees F
Frost-free period 160 to 180 days
Farmland classification Farmland of statewide importance
Map Unit Composition
Everett and sundar soils 100 percent
Estimates are based al observations,descnpbans,and tra/sects of
the Inapunit.
Description of Everett
Setting
Landform Terraces
Parent material Glacial outwash
Typical profile
H I -0 to 7 inches gravelly ashy loamy sand
H2-7 to 21 inches, extremely gravelly sand
H3-21 to 60 inches very gravelly sand
Properties and qualities
Slope 5 to 15 percent
Depth to restnetive feature More than 80 inches
Natural drainage class Somewhat excessively drained
Capacity of the most limiting layer to transmit water(Ksat) High to
very high(5.95 to 19.98 inthr)
Depth to water table. More than 80 inches
Frequency of flooding None
Frequency of podding None
Available water storage in profile Very low(about 2.5 inches)
Interpretive groups
Land capability classification(irrigated). None specified
Land capability classification(nonirigated)- 4s
Hydrologic Soil Group A
Forage suitability group Droughty Soils(G002XN402WA)
Hydnc sod rating No
Data Source Information
Soil Survey Area Mason County,Washington
Survey Area Data: Version 15,Sep 16,2019
tt� Natural Resources Web Soil Survey i2f8m5
Conservation Service National Cooperative Sad Survey Page 1 of t
File Original and F,Ml copy corm Notice of Intent WF
Department of E.Viogy WATER WELL REPORT UNIQUE WELL 10 8 AKR414
5—nd Copy D-Owner'.Copy 1'7" STATE OF WASHINGTON
Third Copy Millers copy 5� Water Right permit NO N/A
0,��YWIJLR-"l—I SHANNON 1,NIR IONT AW.-v 211ft%j"j;K -0. -ELF�Aflj,V.4KIR -0- -
,e WINN 'a
'fAXT1AJ---:FI W) 1 L j?1
(3)PROPOSED USE: Industrial Munaryr (10)WELLLOO orDECOMMMIONING PROCEDURE DEG
triglit— Teat Well othe", F.—
QI DdW star nears a thearelarl nests+straaru o.n.am.con r tsar are ererylar carer ettattaa
.1.110naellan,
14)TYPE OF WORK: Ownw.ri—b., f—11(if more Irian one)
x New Well Method .--WTERLAL FRM TO
Deepened 'Dug Bored BROWN SAND
Reconditioned :cai Dn— BROWN SAND AND CLAY 10 37
X!Rotary jetted BROWN CLAY AND SAND 37 1125
0 (5)DRAENSIONS: six —h--BROWN SAND AND CLAY VVFFP,!.$-_,-- in
r- 0miled 160 feel1).PM ot�ompknw.011 141 f! BROWN SAND WIS
0 BROWN CLAY ANDSAli
(6)CONSTRUCTION DETAILS: _1—
ru Calling Installed:
E IX Welded 6. Man,from, +1,5 R to to I
Lin.,nstafto D—from It to IL
o •Threaded "Do.from R 10 IL
i-
r- parfonirlIgnil 12ym 00N@
yllk TM o4pa"Micamw____ —
saw I Its
A
Tit"I-* '1A'PW'I "";m
ft"f JOHN"
Mo 't�o TJ!L
6 W kwt I�' v" ! ft
#I v as _j L
I,— IL It* IL
Lr--�M Eggs U am ff
IL
111771.1 rq_1 v 14 1 1
lm
taw tat ZYM Ewa U 1b MW 01111M u fi
MJ1"1-?`ftd,AMA
Lu t:WAA-t0-00VVMuMWA&~ CN.X-F*--
"X*M do Ill
(?)PUMP-, Iftrufaloww'Navine
0 Type HP
z ($)WATER LEVELS' Lana-wrfacoel."lion aboals mean seat lerel a WO'k Slay"V109004 .'l C-4-6 311112005. .19
S1.1-c sew,
--22— 34111 WELL CONSTRUCTION CERTIFICATION:
An.s—press— Iti.per.0-0—1h Dot. I r,csnsmuasd andw accept respionswirry hu-ramiucluon of this well.and sits
>s Artesian water is controlled by (Cap..I.,at,) pcimoialnce with&it wa,thingion well_ttmidibn standard, M.1-1,used
0
C" and(me information reported above 11e true to my best knowledge and belief
.6 (9)WELL TESTS:0-0—m—wnt..I«level hi lowered below slats,ewi Type orP"t Name NICHOLA3 J.ERNS? U-nse No
was a pump lest made? __�Y"IX�N. I Yet by~? il—ewd DrilleallErg-1 2147
Yield get Mmm wilt It dravidoom after n"
LIJ Yield gal"m wOn It Mrs I-me.Name I.,cans*No
0
yield gal'r—wan M drawd,own after hr. CmIl.g C—PMAP2�DR�4JNQ CO.
R.comamydt.(hme
Iran well top to isvwye" (S19nd) III License No 2147
ETime Wale,L..1 T Walker Lewi Time WSW Level
Ad""PMX 2227 BELFAIR WA-98528
Conl1iiii",
CL R"WhIfleas 100 TOPDOJDC054RA Date 3/1512004
Date of test
O B..W,1"! 10 gainmin—Mlit 10 e.dnapwa Off _I hr. (USE ADDITIONAL SHEETS IF NECESSARY)
Aat.sl "Imm with stem set at IL far ets
ja ECdM is FA EQual OPPWui and arn0 Aflmliva ACAIM ornplum.Fat
ql#rll. ads *I"wtpilmnaftft nrwM,tweem"waw Rewoo"ts%O -At
TonnVerem of volix wee&dda,"analiplai mew elver&%a (w 4w4m The I,RR ftobw IF mm 407 em.
APPENDIX C
SLOPE STABILITY
1 . O O
1 . 1 O
1 . 2O
1 . 3 O
1 . 40
1 . 50
1 . 60
1 . 70
1 . 80
1 . 90
. 00
956
P jact F,:L I- Visit>n project
Darr- -* e+ Static Analysis
Analysis _ Bishop
$TAMI.C,2002 MZ A&A-lor_w• I.ra
1 . 0 0
1 . 1 0
I = 0
-L 30
1 . 40
1 . 50
1 . 60
I . 70
1 . 80
o 1 . 90
n . 00
r->.r(Z)j 4a, tt Final ± .s :L ri Pr j act
--k t ak:E:L I eq DynaLmic Analysis
Analysis Bishop
APPENDIX D
EROSION CONTROL
GEOTEXTILE FABRIC
WRAP AROUND TRENCH
TO AT LEAST ENTIRE
BOTTOM OF TRENCH
BEFORE PLACING GRAVEL 2'x2'x5' WOOD POST OR
12' DEEP, 8' WIDE TRENCH EQUIVALENT OR BETTER
FILLED WITH 3/4' TO 1 1/2'
WASHED GRAVEL OR VEGETATION
It zs F.
DIRECTl1K OF — EXISTING
WATER FLOW it GROUND SURFACE
as rt .
SILT FENCE — CROSS SECTION
N.T.S.
2'x2' WOOD POST (TYP) GEOTEXTILE FABRIC
OR EQUIVALENT OR BETTER AND WIRE MESH
@ 6 FT MAX. O.C.
s Fr VA Fr
EXISTING --
GROJND 5*WFALE
12- DEEP, W WIDE
FT
TRENCH FILLED WITH 1
3/4' TO 1 1/I"
WASHED GRAVEL OR VEG TI
BOTTOM EXTENTS OF
GEOTEXTILE FABRIC SILT FENCE — DETAIL
N.T.S.
PROVIDE FULL WIDTH
3/4 IN TO 1 1/2_UN2o rT r INGRESS/EGRESS
CRUSHED GRAVEL
PLACED AT 6 IN
MINIMUM DEPTH
WELL—DRAINED
SOILS
—0.02 IN/MIN Full LENGTH
R=25 FT MIN
4
ACCESS ROAD
STABILIZED CONSTRUCTION ENTRANCE
N.T.S.
k-ZW EPMJ174 NBTE5-
NFk4. FOTF.SN
`EE.LIN'_,FOR PAW SLIPEY
.:J01LB THE TEFTO''A;,V V:Z'IU4 At,F SECARJNT TU0T{".OL HILASUITES>]U IN W
H&5.E MOM I-00M TO LE R44EY.JATE lk VJ':';i��IRL4rlllk,THE I43FNTAA4,11Ik F,.AEFME SEEUBY,TY.D"TAI L NEENLO'twfk.'E N4"d3F CaNTAL
HILL"IBETALL ARMORIAL EMAL74 40 SEDIUMEW CWTUL FAMETIEB. MEASII.S"A)CH AS MDZNT TIDNIRA ,MTERCE?TOIL CRIES.
ALL EKIDIII AM SE MENT=KTB3 FAU TIES A"Win=SHILL DE .VALk:�, LE`%EL .'.T'REPI':E'M AND SEUENT 741tSLS.
vvii=DA[LT om DIEOIATtLi waTA11E0,IF Ham'. Z.THE MEB NEk SH PLL ICE rll R WITH FAMILY FM IrAWALE,
ALL G=bt AND:IFVEMT:MTAML FACD- Ei ARM WVJ=SHALL IE LEFT INFtLIOVD4 S..(t'FALE Ri7YEI•EI8145.PERFW A ALL WERAMM '
'E UNTIL THE M' :LDPE M'`EAF. HAVE IM PEWjlENTLY STATOLVER OPK rVv°CR.DL'X:LAH:?U THE A-WE
%�£EYIEI tTiECOAtEYU,ATRINfi,AX SHTM BELOW',AMID nULD HE
E,+TIIXMN(210=31.WOTFZ, N)PP'LTEI AT THE PLATE_OF LX-4 PTIIAOLS --V k.CW-
-L?lm DEL.+;}"LStemo XCTI9EESt MAY_ANIB Co.TD7Kh u WELL
All fOlEA1S VHBCH HAAR,TI•EN ffiTBrF1'En OF VE'MATM tHIE L.iF:'T, RE>VIE I�r 15P,,T3w AMUTHEe Rf!:WE*"m 04 t1EG£IiaFY lr TU
TIIEIiFF.ACTMETS&MR VTETME MHO FTItTM VOAHI U MR�A7'EO A FM rFf Ar u IMTE'.:T THE ',TOT -:T-,AWr,',C,
THE:LN=f lUTIUM 11113",ALL DITATILI0111311 ARAM NAST BE ti StiEY kEV?: �LfJITED P.ETYEEP I4a,.E1AKk I ME Y P-1.'01,
7IrAlujm PL VL7N�OE#M11 ANT=1% TF�� ML ORAL OF THE SEED'AEI VILL FE K:£IESaMr tares.
TIAEwIN= TD THE TUE UpTFAIG faV=,)"TTLE.>, .RE t147,LLEAA i 1A::Tly_
VZ♦L MY X ACM"ASU MtSM TM ItOHOit OF&MM THUM G,FEk`PLI EW1 AW TO DE A.SED A(51IJI'7T0: TO `.:I"LIE;:T
7SEASON!
HOWEVER,SF 4 MAY MBE WHEIIE t IT li IM THE IRIMWT OF kEl2IWD41a:.THD�I.AMOUNTS SNnLD 1/E -011141'El!, EaM£C1:.LL;BUT HCIET ALM IE W-404DITED WITH HRILFI*Ml IETTW Ax1ALEMT TO VATM'WtXT:W. vETLAMUD..
AM40M TTIEATklB1T.
LIETHEF[L13RNONG.47LUkAi61ED WEI KF.ILRE FOR ICROM!
(MAY I THRQ SEPTEMBER 33) -- THE CLEARING OF LAND.INCLUDING THE CVNTRUL. OR A COUNTY APPRIIVEC ALTERNATE SEED MIXTURF
VAL OF EXISTING VEGETATION OR OTHER GRULAD COVER, MUST BE LINITLII TO
NLY AS HJCH LAND AS CAN RECEIVE APPRIYRIATE PROTECTIVE COVER OR BE PRO-PGRTIUHS PURITY GERMINATID
TIERVISE STAIIL]ZEO,AFTER HAVING BEEN CLEARED OR OTHERWISE DISTURBED NAME BY WEIGHT(k) ('/.A (k
Y NO LATER THAN SE.rCMIBER 30 IF A GIVEN YEAR.UNLESS IMMEDIATE
TABILIIATICN IS SPECIFIED IN TIE EROSION AND SEDIMENT CMTR13L PLAN.ALL RrDTOP (ACRIISTIS ALBA' A 92 93
REAS CLEARED DR OTHERWISE DISTURBED MUST BE APPROPRIATELY STABILRED ANNUAL RYE (LOLIUM MULTIFLERUM) 40 90 90
ROUGH THE USE OF MULCH$NG, NETTING, PLASTIC SHEETING,MSE34 BLANKETS, CHEWING FESUE AC 97 80
PEE DRAINING MATERIAL, ETC., BY SEPTEMBER 30 OR SOONER PER THE APPROVED (FESTUCA RUBRA COMMUTATA)
AN OF ACTION UNLESS OTHERWISE APPROVED BY THE COUNTY, SEEDING, (JAMESTOWN, BANNER, SHADGM, KUKET)
RTIL77ING AND MULCHING Or CLEARED OR OTHERWISE DISTURBED AREAS SHALL HE WHITE DUTCH CLOVER 1C 96 90
RFORMED DURING THE FOLLOWING PERIODS.MARCH 1 M MAY 15, AND AUGUST 1J TO (TRIFOLIUM REPENS)
EMBER L SEEDING AFTER OCTOBER 1 WILL BE DONE WHEN PHYSICAL COMPLETMN
THE PROJECT IS IMMINENT AND THE ENVDRDMENTAL CONDITIONS ARE CONDUCIVE MULCHING
SATISFACTORY GROWTH IN THE EVENT THAT PERANENT STABILIZATION IS NOT
OSSIBLE.AN ALTERNATIVE METHOD OF GROUND COVER, SUCH AS MULCHING,NETTING.L MATERIALS USED FOR MULCHING ARE RECOMMENDED TO BE WOOD
ASTIC SHEETING, EROSION BLANKETS, ETC., MUST BE INSTALLED BY NO LATER THAN FIBER CELLULOSE, AND SHOULD BE APPLIED AT A RATE IF 1000
EPTEMBER 30. P13UNDS PER ACRE,
2.MULCH SHOULD BE APPLIED IN ALL AREAS WITH EXPOSED SLOPES
'a THE EVLIMT TH}1 ODHCIA(CTIUN AIOTrVlTIES OR U 14LA YITL➢EVULUP IT REATEW 744'1 217 :HClk0UNrALAER'fOEALA
-TIYITIE3 AHE MSi:AHnMM FMt AT LEAST• MALC JTrA DAM THE a Ap1CHG-4:UtUU BE GS£D 3704pIIATELY AFTEIR VEDDIG IF?f
--.1fEI2.KOT1Yl?ACTUR SI.MLL lE KWUMCME FOR TTf DITXTD]!13F ALL ER0110N AREAS VKICH CMBKIT DE SEEDED IEo+YJBE OF'THE FEM[k ALL
S b&C TT CCF(rK L FACILITIEZ 011'Ati ATMY AFTER iTTiil ENLNTR.A*D AT AREAS CFT7IJaRm Y.L m OWL IE tDYERCD B11 Ntl4'FNIEk 6.
AST UNC'.E EVLtY VEER THE OVMEIV COIT11401I11 SHALL ME NOWMSI$1 ETIN
RE M`3MTEMBMMRS An WINO OF ALL E111011ON MO SEODnT=CTTm FM;ILITDL';. 7T]°5014.,"
ET W-ABO( [OLTUAC14 f THR'J APXL 3It—UH SITES NONERE UMff THETA To L TWMIL'SHOLXD BE LREO FO THI;MELEL'T AC TU HM*I-Y
?-t'rM ACTIVITY IS IN POICONNE99. THE 0.E0I14G Or LAWL VACLS WW, THE DCAM F'V=SOILS.
VIDV&OF EXIfT916 VELETATIUM MUM WWA WQuBW CLOVER,SHALL BE LIMITEE Z TOPSOIL 01DULD BE PUREED ON SLOPES KIT EYLFEM%M
Ai :4"LAM AREA AS nM DE tOINSRED OR STAYILTIE'B WITHIN E4 HIDU.S'S IN 3 STkaPH"lll.i AEiC 'STfJCKPILIMi OM-3T7E..'lIIL^o SHALL IBLY WE
EYEMT A l33TE It O IS H�ELIOTED AMaf tp E7U411M AiND SEDOIEMRi PFRIUTTEL IT 73%SOIL M FRIAILE WO LIIWY L AA,SAW LOML
TFF-SITE A tIERV'ETA SILT LCWK .WtY CLAY LOAD.,,MAY LOW.
L CLFhO'S Ill ZCFTL=M AREAL SHALL RECEIVE AFFIRDIM LATE PAUTECTIVE 4.STRIA G SHALL BE CCWD=,TO THE TMHEAUTE CZRf%TO=TVBR
OR]E OTHE WM ITAOMLIPM SM'JI AR WA,f#(IIE..METTIN%RA"r.. aw-mi A I= TO 1FJO 0I.11 ITltlrnkI OE°LH DC room.WI
E1TNM KAAHIETS,.FREE p""MATERIAL.ETC,.V O 3 MY&AFTER]EMH HBFT WAW DEPEX ►1:IN THE PAgrD!YLm Sm,ALL
VM IlEEAI LIEAVED OR IITHERVAE BII E=Ell W!QT lEUV ACTIVELY VOTED. TIVRFACE fA9MVF COMTRlt1 BTII CTJREI SHALL>F Ba Pil 71ffTIRE
"Lpqsa
T FENCING. SEUIMENT TRAPS. SLTIIMENT PLIN",ETC., WILL f BE Vxwrl)AS 1701
MY
DEQUATE COVER IN AND OF THEMSELVES.IN THE EVENT THAT ANY LAND AREA NOT
NG ACTIVELY WORKED REMAINS UNPROTECTED OR HAS NOT BEEN APPROPRIATELY
TABILIZED S DAYS AFTER HAVING BEEN CLEARED, ALL CONSTRUCTION ACTIVITY ON
HE SITE, EXCEPT FOR APPROVED ERUSION AND SEDIMENT CONTROL ACTIVITY, SMALL
MFEDIATELY CEASE UNTIL SUCH A TIME AS AFOREMENTIONED LAND AREA HAS BEEN
PPRUPRIATELY PRQIECTED OR STABILIZED.
STOCKPILE MANAGEMENT
1.STOCKPILE SHALL BE STABILIIID(WITH PLASTIC COVERING OR OTHER APPROVED DEVICE)DAILY BETWEEN NOVEMBER 1 AND MARCH
3L
P.IN ANY SEASOI. SEDIMENT LEACHING FROM STOCK PIES MUST BE PREVENTED,
I TOPSOIL SHALL NOT BE PLACED WHILE IN A FRO7EN OR MUDDY CONDITION,WHEN THE SUBGRADE IS ExCESSIvELY WET OR MEN
CONDITIONS EXIST THAT MAY OTHERWISE BE DETRIMENTAL TO PROPER GRADING O PROPOSED SODDING OR SEEDING
AREVHM-ETTABLffiHEL CFATC'04 THE AMiAt TO BE TOPFOI.EE .MIN.K MAMMTA➢RT ArT.001IN.5 TO THE WffOA0 M.AR'6
ITAIILELED CORDT14,ALTIDN D4rr%4ICE
L MATMEAL SHALL BE 4 W14 TO A INCH OvARH VALLT a TO n WN FIX PESI'DENTIAL SPtCLE FAMILY LUTZ AMD MAY BE
TOP-1119010 WITH 1 INCH TO?INCH ROCK, (STATE 3TArANIM ^..PE!:FIC:Ai[D1TD.:.EErION
t THE:ROM PAD SMALL A AT LEAST HE ]ITCHES THL'1t A"39 FEET LOW 4W FIST FOR SITE&ATH LEU T4 M I ACRE OF
ASTIR KO SUILi. WIDTH SHALL BE FULL VIDTH OF THE VEHICLE INGRESS AND EIWESS AREA.SMALLER PAD$ MAY TE APPROVE➢
FOR SINGLE-FAMILY RESIDENTIAL AND SMALL COMMERCIAL SITES.
3.ADDITIONAL ROCK SHALL BE ADDED PERIODICALLY TU MAINTAIN PROPER FLNCT113N [IF THE PAD.
4.IF THE PAD DOES NOT ADEQUATELY REMOVE THE MUD FROM THE VEHICLE WHEELS, THE WHEELS SHALL BE HOSED OFF BEFORE
THE VEHICLE ENTERS A PAVED STREET. THE WASHING SHALL BE DONE ON AN AREA COVERED WITH CRUSHED ROCK AND WASH
WATER SHALL DRAIN TO A SEDIMENT RETENTION FACILITY OR THROUGH A SILT FENCE.
[LT FENCE
GEUTYXTILE FILTER FABRIC TYPE SHALL BE PER SPECIFIED IN THE'STURW&TER MANAGEYENT 94"L
IN 'It PLIGLT SULW1 BASIN,' UN APP'LICABLL C"" STANDARDS
,GEOTL'XTILE FILTER FABRIC SHALL K PURCHASED IN A CONTINJOUS 001 CUT TO THE LENGTH OF
.H BARRIER M AVOID USE OF .HINT&IF JOINTS ARE NECESSARY, FILTER FABRIC SHALL BE VL=FD
OGETEEIY ONLY AT A SUPPORT POST VITH A MINIMUM 6-INCH OVERLAP AND SECURELY FASTENED AT
H EMI£ TO THE POST.
S
TANDARD FILTER FABRIC SHALL 8E FASTENED 1MSHN'G 1'STAPLES OF FIE MIRES tMUE R)N3S1 A IN
SHALL BE SPACED AND PLACED AT DEPTHS INDICATED IN THE.DETAILS ON THIS SHEET,AND
SECURELY INTO THE CJHOIAID,MESH SWILL BE 2'X2'XIA GAUGE OR EQUIVILENT, ME WIRE MESH MAY BE ELIMINATED IF
TRENGTH FILTER FABRIC (MUNOrLAMENT), AND CLOSER POST SPACING IS USED,
SHALL BE EXCAVATED ACCORDING TO THE DETAILS ON THIS SHEET ALONG THE LINE EF THE
ND UPSLOPE FROM THE SILT FENCE,
FENCES SHALL BE LOCATED DOWNSLOPE FROM THE CLEARING LIMITS OF THE PROJECT.
APPENDIX D
DRAINAGE DETAILS
HOUSE
ROOF DOWNSPOUT
SERVES UP T❑
700 SF OF ROOF
SO FT MIN
VEGETATED
FLOW PATH
DOWNSPOUT
EXTENSION
ROOF DOWNSPOUT AND SPLASH BLOCK DETAILS
N.T.S.
GEO Z0,?4/- aovZJ
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: rt tLa l V i Zr'b-P
Permit#: TT711720W—oa27 5 Parcel* 12 3 3v- Sa — 0009 2
Date(s)of the Document(s)reviewed: U Zo vzo
1. (a) A discussion o eneral geologic conditions in the vicinity of the proposed development,
OK? Comment:
(b) A discussion o specific soil types
OK? Comment:
(c) A discussion of ground water conditions
OK? ✓ Comment:
(d) A discussion of he 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 vicinity, as available in the referenced maps and records.
OK? ✓• Comment:
2. A site plan that identifies the im.portant'development and geologic features.
OK? ✓Comment:
3. Locations and logs of exploratory holes or probes.
OK?_,/Comment:
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.
OK?�_Comment:
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.
OK?_�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 safety factor is 1.1 and the quasi-static
analysis coeffients should be a value of 0.15.
OK? Z_Comment:
7. (a) Appropriate restrictions on placement of drainage features
OK? /_Comment:
(b) Appropriate strictions on placement of septic drain fields
OK? V Comment:
(c) Appropriate restrictions on placement of compacted fills and footings.
OK?_�_Comment:
Page 1 of 2 Form Effective June 2008
(d) Recommended buffers from the landslide hazard areas shoreline bluffs and the tops of other slopes.
OK? �/ Comment:
(e) Recommended setbacks from the landslide hazard areas shoreline bluffs and the tops of other slopes.
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 vegetation
removal.OK? ✓/Comment:
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.
OK? Comment:
10. An analysis of both on-site and off-site impacts of the proposed development.
OK? ✓ Comment:
11. Specifications of final development conditions such as, vegetative management, drainage, erosion control, and
buffer widths
OK? Comment:
12. Recommendations for the preparation of structural mitigation or details of other proposed mitigation.
OK?_�Comment:
13. A site map drawn to scale showing the property boundaries, scale, north arrow, and the location and nature of
existing and p oposed development on the site.
OK? Comment:
Are the Documents signed and stamped? By,whom? iC
License Li ense type: �
FIRST REVIEW Approved ❑ Need more info.
If not approved, what is the next action/recommendation for further action?
Reviewed by , on O v 2-1). Time spent in review:
SECOND REVIE / UPDATE ❑ Approved ❑ Need more info.
Reviewed by , on . Time spent in second review:
THIRD REVIEW/UPDATE ❑ Approved ❑ Need more info.
Reviewed by , on .Time spent in third review:
Disclaimer. Mason County does not certify the quality of the work done in this Geotechnical Report.
Page 2 of 2 Form Effective June 2008