HomeMy WebLinkAboutGEO2020-00079 - GEO Geological Review - 9/14/2020 MASON COUNTY
COMMUNITY SERVICES Geological Assessment
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Instructions:
This checklist must be submitted with a Geological Assessment and completed,signed,and stamped by the licensed
professional(s)who prepared the Geological Assessment 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 Jeff Keesler Parcel# 22325-44-91090
Site Address 1473 NE Mission Creek Road
(1) A discussion of the geologic conditions in the general vicinity of the proposed development,with geologic unit
designation based on referenced maps.
Located on page(s) 5
(2) (a) A discussion of ground water conditions,
Located on page(s) 6
(b) A discussion of the estimated depth to water,
Located on page(s) 6
(c) A discussion of the quantity of surface seepage,
Located on page(s) 6
(d) A discussion of the upslope geomorphology,
Located on page(s) 3
(e) A discussion of location of upland waterbodies and wetlands.
Located on page(s) 3
(3) The approximate depth to hard or dense,competent soil,e.g.glacial till or outwash sand.
Located on page(s) 5
(4) A discussion of any geomorphic expression of past slope instability(presence of hummocky ground
or ground cracks,terraced topography indicative of landslide block movement,bowed or arched trees
indicating downslope movement,etc).
Located on page(s) 4
(5) A discussion of the history of landslide activity in the vicinity,as available in the referenced maps and.
records.
Located on page(s) 8
(6) An opinion on whether the proposed development is within the landslide hazard area or its associated buffer or
setback and the potential for landslide activity at the site in light of the proposed development.
Located on page(s) 8
(7) A recommendation by the preparer whether a Geotechnical Report should be required to further evaluate site
conditions and the proposed development of the subject property.
Located on page(s) 11
(8) If the presence of a hazard is located within 300 feet of the proposed development,then the following are
delineated on a geologic map/site map:
(a) The area of proposed development,
Located on map(s) n/a
(b) The boundaries of the landslide hazard area(top,both sides,and toe),
Located on map(s) n/a
(c) The associated buffers(top,both sides,and toe),
Located on map(s) n/a
(d) Building or other setbacks(top,both sides,and toe),
Located on map(s) n/a
(9) 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(Appendix A)
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 Geological Assessment
dated July 23,2020 ,and entitled Keesler Single Family Residential Property ,meets all the
requirements of the Mason County Resource Ordinance,Geologically Hazardous Areas 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.
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Disclaimer:Mason County does not certify the quality of
the work done in this Geological Assessment.
Page 2 of 2
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Geological Assessment
Keesler Single Family Residential Property
1473 NE Mission Creek Road, Belfair
Parcel No. 22325-44-91090
Mason County, Washington
July 23, 2020
Project#20118
PLANNING
Prepared For:
Jeff and Miranda Keesler
1473 NE Mission Creek Road
Belfair, Washington 98528
Prepared By:
Envirotech Engineering
PO Box 984
Belfair, Washington 98528
Phone: 360-275-9374
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7/23/2020
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
2.3 SURFACE DRAINAGE..........................................................................................................................3
2.3.1 Upland Water Bodies.................................................................................................................3
2A SLOPE AND EROSION OBSERVATIONS...............................................................................................4
3.0 SUBSURFACE INVESTIGATION.....................................................................................................5
3.1 FIELD METHODS,SAMPLING AND FIELD TESTING...........................................................................5
3.2 GEOLOGIC CONDITIONS....................................................................................................................5
3.3 SPECIFIC SUBSURFACE CONDITIONS.................................................................................................5
3.3.1 Groundwater............................................................................................................................... 7
4.0 ENGINEERING CONCLUSIONS......................................................................................................8
4.1 LANDSLIDE HAZARDS.........................................................................................................................8
4.1.1 Landslides and Slope Stability Analysis....................................................................................9
4.1.2 Surface and Subsurface Drainage............................................................................................ 9
4.2 EROSION HAzARDS............................................................................................................................9
4.3 SEISMIC HAzARDs.............................................................................................................................10
4.4 OTHER CONSIDERATIONS.................................................................................................................10
5.0 CLOSURE.............».......................................................................».....................................................11
Appendix A-Site Plan
Appendix B-Soil Information
1.0 INTRODUCTION
Envirotech Engineering, PLLC. (Envirotech) has completed this geological assessment for a
residential property located at 1473 NE Mission Creek Road,identified as parcel number 22325-
44-91090 in Mason County, Washington. As presented herein, this assessment 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 soils descriptions in the
Subsurface Investigation Section; and, assessments for landslides, erosion, seismic hazards, and
other considerations in the Conclusions Section.
An initial geological/geotechnical evaluation of the project was conducted by Envirotech on July
14, 2020. It was determined that natural slopes between 15% and 40% were present within 300
feet of the project. Due to these slope grades, a geological assessment is required pursuant to
landslide hazard areas of the Mason County Resource Ordinance(MCRO).
During the evaluation and site visit by Envirotech, surface and subsurface conditions were
assessed in order to determine if further geotechnical studies are required.After completion of the
field work and applicable Project research,Envirotech prepared this geological assessment.
1.1 Project Information
Information pertaining to the project was provided by the proponent of the property, and
observations from a field visit by Envirotech.The proposed development is expected to consist of
a new single family residence, on-site septic system, and other ancillary features typical of this
type of development. Approximate site development with relation to existing site features are
illustrated in the Site Plan in Appendix A of this report.
1.2 Purpose of Investigation and Scope of Work
The purpose of this geological assessment was to evaluate the project in order to confirm that the
proposed development is outside of any landslide hazard area and its associated buffers and
setbacks as determined in the MCRO. The investigation included characterizing the general
project surface and subsurface conditions,and evaluating the suitability of the soils to support the
planned site development. In order to fulfill the purpose of investigation, the geological/
geotechnical program completed for the proposed improvements of the Project include:
• Review project information provided by the proponent of the project;
• Conduct a site visit to document the site conditions that may influence the construction
and performance of the proposed improvements;
• Define general subsurface conditions of the site by observing soils within test pit
excavations, review well logs from existing wells near the Project, and evaluate
geological and hazard maps depicting the site geology for the vicinity of the project;
• Perform soils testing,such as visual classifications,to determine selected index properties
of the soils;
• Complete an engineering assessment supported by planned site alterations and the surface
and subsurface conditions that were identified by the field investigation, soil testing,and
applicable project research;and,
• Establish engineering conclusions based on findings and anticipated development.
Envirotech Engineering Geological Assessment
PO Box 984 page 1 Parcel 22325-44-91090
Belfair,Washington 98528 Mason County,Washington
Ph. 360-275-9374 July 23,2020
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Envirotech Engineering Geological Assessment
PO Box 984 page 2 Parcel 22325-44-91090
Belfair,Washington 98528 Mason County,Washington
Ph. 360-275-9374 July 23,2020
2.0 SURFACE CONDITIONS
Information pertaining to the existing surface conditions for the project was gathered on July 14,
2020 by a representative with Envirotech.During the site visit,site features were documented that
may influence construction or reveal potential geological hazards. This Surface Conditions
Section provides information on general observations, vegetation, topography, drainage and
slope/erosion conditions for the project and surrounding areas.
2.1 General Observations
The property currently has an existing mobile home, driveway, other typical features and is
surrounded b residential development. The site is partially cleared. Vegetation on and near the
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property consists primarily of firs, maples, 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 for an illustration of the general slope indicators with respect to the planned
development.
Descending slopes exceeding 15% are located on and beyond the property. Average slope grades
are approximately 35% with a vertical relief of approximately 30 feet. The top of slope was
slightly over-steepened from a small amount of fill and brush.
2.2.1 Upslope Geomorphology
Ascending grades are generally located to the east of the planned development. This
slope is relatively minor within 300 feet of the Project, with no apparent slope grades of
at least 15%. The upland area of the property is situated on a hillside and crest.
Landforms are primarily of glacial origin with centuries of weathering overburden.
Additional geomorphology that is pertinent to both upslope and downslope areas are
provided in the Subsurface Investigation Section of this report.
2.3 Surface Drainage
The majority of the stormwater runoff originating upslope from the anticipated development is
expected to be minimal to moderate. Significant scour, erosion and sediment transport was not
apparent near the project where development is expected.Mission Creek is located near the slope
toe,and has normal scour.
2.3.1 Upland Water Bodies
There are no apparent water bodies or wetlands located upslope from the planned
development that would significantly influence the Project.
Envirotech Engineering Geological Assessment
PO Box 984 page 3 Parcel 22325-44-91090
Belfair,Washington 98528 Mason County,Washington
Ph. 360-275-9374 July 23,2020
2.4 Slope and Erosion Observations
The existing moderate slopes 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 or naturally 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.
The above mentioned indicators, or other signs of 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 Geological Assessment
PO Box 984 page 4 Parcel 22325-44-91090
Belfair,Washington 98528 Mason County,Washington
Ph. 360-275-9374 July 23,2020
3.0 SUBSURFACE INVESTIGATION
Information on subsurface conditions pertaining to the project was gathered during research and a
site reconnaissance. The site visit was accomplished on July 14, 2020 by a representative with
Envirotech. Specific information on field methods, sampling, field testing, subsurface conditions,
and results from soil testing are presented in this section of the report. Appendix B has pertinent
information on subsurface conditions for the Project,including test pit log(s)representative of the
site soils,and water well report(s)originating from the subject property and/or nearby properties.
3.1 Field Methods,Sampling and Field Testing
Information on subsurface conditions for the Project was accomplished by probing anticipated
foundation areas with hand tools, and observing soils within test pit excavations and/ or earth
cuts. Information on subsurface conditions also included reviewing geological maps within the
Project vicinity, and water well reports originating from nearby properties. No soil samples were
collected for this Project.Envirotech measured the relative density of the in-situ soils by gauging
the resistance of hand tools.
3.2 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. Hehemann, Isablle Y. Sarikhan,
and Robert L.Logan,July 2009,provides the following caption(s)for the project area:
Vashoa recessional oum-ash--Gravel and sand:locally includes silt or
clay;tan to gray;rounding and sorting diverse.but most commonly
subrou nded and moderately sorted.stratified and loose.ranges from a few
feet to a few tens of feet thick-but may locally exceed 100 0 along Misuon
Creel:deposited by Vashon meltwater in outaash channels or isolated
basins:genrall}al •less compact than adsauce oumash(unit Qga).but in
some exposures difficult to distinguish from unit Qga where not separated
by till:stratigraphically overlies till Most deposits of this unit are
ice-proximal and difficult to separate from unit Qgic.locally resulting in
gradational boundaries and poor distinction between units Qgic and Qgo
(and subtnnts).This difficulty is illustrated.for instance.by a"leaping"
out ash channel(Fig.2).Locally dnided into:
Envirotech Engineering Geological Assessment
PO Box 984 page 5 Parcel 22325-44-91090
Belfair,Washington 98528 Mason County,Washington
Ph. 360-275-9374 July 23,2020
�, nusinul—Silt,sand,and gravel;clasts typically well rotmded;typically
well sorted and loose:stratified to massively bedded:deposited in streams
and adjacent banks.The sediment source is most commonly reworked
recessional outuash.ablation till.advance oanti ash.and(or)
glaciolactmsh me deposits.but may meiude lodgment till.nonglacial
deposits,and bedrock.Exposures locally resemble the unit's sediment
source units.a particularly notable feature in the Umon River valley.
where the unit is mostly derived from glaciolacustrine and(or)ice-contact
deposits(units Qgof and Qgic).Shear-suave velocity profiles confirm.
however.that unit Qa forms a more(liver se deposit than unit Qgof and at
least some deposits of unit QVc(Fee.4). Subunit Qoa is older alluvium
that resembles unit Qa in every sway but forms elevated relict terraces.
Most appear to be tied to an elevated base level that prevailed prior to a
local base-level louviimg events)(see discussion of elevated terraces
under Structure).Rliere unit Qoa is correctly identified along the lower
reaches of streams that are graded to sea level the age of unit Qoa should
not exceed about 6.000 years because prior to that.sea level was
significantly tower.which likely resulted in an erosional setting that
precluded deposition of alluvnnu As mapped.the unit is generalh
Holocene but may locally include some unrecognized recessional outvwash
ten aces(unit Qgo)and other late Pleistocene deposits.A map boundary
mismatch with the Vaughn quadrangle to the south resulted where Logan
and INalsh(2007)humped unit Qoa into unit Qa.Elsewhere.the contact
between trait Qa(this map)and units Qgt and Qaf(Vaughn quadrangle)
runs so close to the map boundary that map scale did not permit separating
the eeologic boundaries from the map boundary.
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 described utilizing the Unified Soil Classification System
(USCS). Using the USCS in conjunction with estimated relative densities and other anticipated
engineering properties of the soil, susceptibility for potential landslides, erosion and seismic
hazards may be assessed.
The project is primarily composed of undisturbed, native soils, without indications of substantial
fill. Competent bearing soils were encountered at 12 inches below the existing native ground
surface in locations where the ground was probed. For engineering purposes, these native soils
consist of distinguishable layers,as presented below.
Soils within the upper 3 feet of natural ground were observed to be primarily poorly graded
gravel with sand(GP). Soils below the upper GP layer were observed to be a fine sand(SP)to a
depth of 5 feet.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(SCS),the site soils are described as Everett very gravelly
sandy loam, Et„ with 8% - 15% slopes. See the soil map below, and the applicable SCS soil
profile(s)in Appendix B of this report.
Envirotech Engineering Geological Assessment
PO Box 984 page 6 Parcel 22325-44-91090
Belfair,Washington 98528 Mason County,Washington
Ph. 360-275-9374 July 23,2020
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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 50 feet below the current ground surface. Surface seepage or perched
groundwater at shallow depths was not observed on-site, nor indicated on the well
reports. However, some seasonal groundwater is expected to flow directly above the
hardpan on occasion.
Envirotech Engineering Geological Assessment
PO Box 984 page 7 Parcel 22325-44-91090
Belfair,Washington 98528 Mason County,Washington
Ph. 360-275-9374 July 23,2020
4.0 ENGINEERING CONCLUSIONS
The following sections present engineering assessments and conclusions concerning the project.
These conclusions have been made available based on the planned construction activities as
outlined in the Introduction Section of this report; general observations of drainage and
topography as summarized in the Surface Conditions Section; and, soil conditions that were
identified by the field investigation and soils testing as outlined in the Subsurface Investigation
Section. Conclusions for the Project that is provided herein, includes pertinent information for
landslide,erosion and seismic hazards.
4.1 Landslide Hazards
For the planned development, as provided in the Introduction Section of this report, it is
Envirotech's opinion that the proposed development is not subjected to or cause adverse impacts
to a landslide hazard area or its associated buffer or setback as defined in the MCRO. This
conclusion is based on the contents provided in this report.
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.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, excessive and/or repeated surficial slope
movements, if not repaired, may represent a threat to the structural integrity of the slope.
Maintenance of the slope should be completed if the situation does arise in order to prevent the
possibility of further surficial or deep seated slope movements that may be damaging to life or
property.
According to the Department of Natural Resources (DNR) "LHZ—Final A-1 Map —Landslide
Inventory—Mason Watershed,by Sarikhan,et. al.,May 2007,"previous landslide activity is not
recorded near the project. Per the Resource Map from DNR, the Project is not within terrain
labeled `highly unstable' or `highly erodible' relating to soils. DNR labeled portions of this
project as medium to high slope instability with relation to slopes. This delineation is primarily
dependent upon slopes and convergence. Secondly, lithology and precipitation are modeled
within this delineation. In summary, this designation is based on mapping without field
observations or knowledge of the specific site geology or soils. A resource map from DNR is
provided below:
Envirotech Engineering Geological Assessment
PO Box 984 page 8 Parcel 22325-44-91090
Belfair,Washington 98528 Mason County,Washington
Ph. 360-275-9374 July 23,2020
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Map from Washington State Department of Natural Resources Website
4.1.1 Landslides and Slope Stability Analysis
Past landslide activity or high slope instability indicators near the proposed development
was not revealed during the project research.In addition,detrimental landslide activity or
potential high landslide indicators were not observed during the site visit as outlined in
the Surface and Subsurface Conditions Sections of this report. Due to these factors, and
existing/proposed conditions,a slope stability analysis was not deemed necessary for this
project. Considering the planned construction as summarized in the Introduction Section
of this report; the aforementioned surface and subsurface conditions for the project; the
slope stability assessment provided herein; and the Engineering Conclusions provided
later in this report, it is our opinion that the project is not within a landslide hazard area,
and that the proposed site alterations will not encourage a landslide hazard.
4.1.2 Surface and Subsurface Drainage
This project does not appear to experience significant subsurface drainage or surface
runoff. It is our opinion that groundwater or surface drainage is not a limiting factor for
this Project.
4.2 Erosion Hazards
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
Envirotech Engineering Geological Assessment
PO Box 984 page 9 Parcel 22325-44-91090
Belfair,Washington 98528 Mason County,Washington
Ph. 360-275-9374 July 23,2020
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).
Temporary and/ or permanent erosion control measures may be required for any site when land
disturbance is involved. 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 conditions and planned disturbance of this Project include wind-borne silts during dry
weather, and sediment transport during prolonged wet weather. Sediment transport of disturbed
soils could be from stormwater runoff or tracking off-site with construction equipment. Although
an engineered erosion control plan is not warranted for this project, Best Management Practices
(BMP's) should be employed during and after construction. Ordinary BMP's includes silt
fencing,protection of drainage outlets and vegetating denuded areas.
Erosion control information and specifications may be found in the applicable "Stormwater
Management Manual for Western Washington,"prepared by the Washington State Department of
Ecology Water Quality Program.
4.3 Seismic Hazards
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.
There are no known faults beneath this project.The nearest Class `A' or `B' fault to this property
is the Tacoma Fault Zone. This fault is a Class `A', and is located approximately 5 miles to the
south of the Project. This information is supported by the USGS Quaternary Fault and Fold
Database for the United States.
The potential for liquefaction and other earthquake induced hazards are believed to be low for
this project. This is based on subsurface conditions such as soil characteristics and the lack of a
permanent and substantial shallow water table. Subgrade characteristics that particularly
contribute to problems caused by seismic events include submerged and confined, poorly-graded
granular soils. Although gravel- and silt-sized soil particles could be problematic, fine and
medium grained sands are typically subjected to these types of seismic hazards.
4.4 Other Considerations
It is our understanding that the home will be over 30 feet from the top of slope. If this is not the
case,Envirotech should be notified in order to provide additional recommendations due to the fill
soil. Conclusions in this report are based on the type and location of the anticipated development,
and existing on-site and off-site conditions. Site development that significantly deviates from the
anticipated improvements presented in this report, or nearby development that influences this
Project may require geotechnical design recommendations.
Envirotech Engineering Geological Assessment
PO Box 984 page 10 Parcel 22325-44-91090
Belfair,Washington 98528 Mason County,Washington
Ph. 360-275-9374 July 23,2020
5.0 CLOSURE
Based on the project information 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. Therefore, it is recommended that
Envirotech is promptly notified if project and subsurface conditions found on-site are not as
presented in this report so that we can re-evaluate our recommendations.
This report presents a geological/geotechnical assessment, and is intended only for the owner,or
owners' representative. Furthermore, this report is only valid for the project information and
location described herein.
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 Smith,M.S. Michael Staten,P.E.
Staff Geologist Geotechnical Engineer
Envirotech Engineering Geological Assessment
PO Box 984 page 11 Parcel 22325-44-91090
Belfair,Washington 98528 Mason County,Washington
Ph. 360-275-9374 July 23,2020
APPENDIX A
SITE PLAN
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SCALE- L INCH=50 FEE
0 50
APPROXIMATE
TOP OF SLOPE
EXISTING
DRIVEWAY
31%±
A=-
r^mrLY
PO
34%±
PO
PROPERTY LINE
4%±
Spit
TPL
PROPOSED DRAINFIELD
PROJECT/ OWNER/UXATIDFY
SINGLE FAMILY PROPERTY
GEOLOGICAL ASSESSMENT
KEESLER
1413 HE KISS=PAEEAI fM
LS1LOFE U CM4T3RE �
WEZE F�LTl)EACIliEF RT'Dr-lRff--Ail.AMC,'Cn PARCEL +-W=
ET760iTPOLOMM rRIN A PL OLIC LIDAA 7AXWCE A 40C AFT$iM14ZATE FNmF C'aP117 %M1i MWM
!t UMMFA2 UN TNITS x:TS 7L.0 WOiE NUT A'ILT5K-7 AT A LT!'LXZ;,, '4iLPf11
inLRVEYM LOC;TUPM IF 317E FFAnAt"MIX&L!OL3 tA—t'a1111Z&Pk-.Y.=9ES'I KXTM0M Al SMW7. OiVOtQIEG1 EI'8'S11Q!/NO
EV HE:WM RELATMH 7o T`E PKf'E7V! Lucl Iq amECH
MAT BF ',-Ann n IN TW RWWIS TW OIWJ LtUft ANM ...s+.. %LEK lbxx%liu
NE001007A-M YAOW➢FA IN THE anl`rT l;ulkL .,-FO MM"AL. r,FFiv, KLiAm WA*036TOR 2L
A4F_1A=mx lrmj OM IPFMFIC FFATIM THFT M,4Y Fa'() Mfi= �x'a79rga7�
rOFFD�DFF flasE Y LM M niM SITET, rs.7�aLa Tfj rExl Pr SITE PLAN
APPENDIX B
SOIL INFORMATION
TEST PIT LOG
TEST PIT NUMBER TP-1
PROJECT: SFR Geological Assessment DATE OF LOG: 07/14/2020
PROJECT NO: 20118 LOGGED BY: MCS
CLIENT: Keesler EXCAVATOR: NIA
LOCATION: Parcel 22325-44-91090 DRILL RIG: None
Mason County,Washington ELEVATION: N/A
INITIAL DEPTH OF WATER: N/A FINAL DEPTH OF WATER: NIA
SOIL STRATA, STANDARD PENETRATION TEST
DEPTH SAMPLERS USCS DESCRIPTION LL PI DEPTH N CURVE
AND TEST DATA 10 30 50
0
o GP Poorly graded GRAVEL with SAND
00
t 001
0
0
z 00
00
0
3 SP Fine SAND
4
5
Excavation terminated at approxirnatey
5,0 feet
6
7
8
9
10
No Groundwater Encountered ENVIROTECH ENGINEERING
Ttus information pertains only to this bwmg and should not be Geotechnical Engineering
interpreted as beng mdicitve of the entne ate
Map Unit Description.Everett very gravelly sandy loam.8 to 15 percent slopes--Mason III
County.Washmgton
Mason County. Washington
Eh—Everett very gravelly sandy loam. 8 to 15 percent slopes
Map Unit Setting
National map unit symbol: 21162b
Elevation. 30 to 900 feet
Mean annual precipitation: 35 to 91 mches
Mean annual air temperature: 48 to 52 degrees F
Frost-free period. 180 to 240 days
Farmland classification: Farmland of statewide importance
Map Unit Composition
Everett and similar soils: 80 percent
Mina'components: 20 percent
Estimates are based on observations,descriptions,and transects of
the mepunit.
Description of Everett
Setting
Landform: Karnes,eskers,moraines
Landform positron(two-dimensional): Shoulder,footslope
Landform position(three-dimensional): Crest,base slope
Down-slope shape: Convex
Across-slope shape: Convex
Parent material.' Sandy and gravelly glacial outwash
Typical profile
Ot-0 to f inches: slightly decomposed plant material
A-t to 3 inches: very gravelly sandy loam
Bw-3 to 24 inches: very gravelly sandy loam
Cl-24 to 35 inches: very gravelly loamy sand
C2-35 to 60 inches: extremely cobbly coarse sand
Proper ies and qualities
Slope. 8 to 15 percent
Depth to restrictive feature: More than 80 inches
Natural drainage class: Somewhat excessively drained
Capacity of the most limiting layer to transmit water(Ksat). High
(1.98 to 5.95 in/hr)
Depth to water table: More than 80 inches
Frequency of flooding: None
Frequency of ponding: None
Available water storage in profile Low(about 3.2 inches)
Interpretive groups
Land capability classification(irrigated): None specified
Land capability classification(nonirngated): 4s
Hydrologic Soil Group: A
r stzt Natural ReseUFCBa Web Soil Survey 7r22r2020
Conservation Service National Cooperative Soil Survey Page 1 of 2
Map Und Description:Everett very gravelly sandy loam,8 to 15 percent slopes—Mason
County,Wastnngton
Forage suitability group: Droughty Soils(G002XN402WA),
Droughty Soils(G002XF403WA),Droughty Soils
(G002XS401 WA)
Hydnc soil rating: No
Minor Components
Alderwood
Percent of neap unit: 10 percent
Landform Ridges,hills
Landform position(two-dimensional): Shoulder
Landform position(three-dimensional) Nose slope,talf
Down-slope shape. Linear,convex
Across-slope shape: Convex
Hydric soil rating: No
Indianola
Percent of map unit: 10 percent
Landform: Eskers,kames,terraces
Landform position(three-dimensional): Riser
Down-slope shape: Linear
Across-slope shape: Linear
Hydric soft rating No
Data Source Information
Soil Survey Area: Mason County,Washington
Survey Area Data: Version 16,Jun 4,2020
i� Natural Resources Web Soil Survey 7/22r2020
+i Conservation Service National Cooperative Soil Survey Page 2 of 2
711
WATER WELL REPORT
ECOLOGY nryNY 1'wPY•Ecol a.2-..w•owan.3'Capp•draw C I R R F.N I
Notice of Intent No.W 249645
ConstructioWDecommissbnrK incirck)
X Construction Unique Ecology Well ID Tag No.ALH 618
Decommission ORIGINAL/NSTALLAT ION Water Right Permit No.
Notkc oflntent Number
PROPOSED USE: ■Dnneaw Q�ndurid ❑LMriapd Property Owner Name Barbara Loodenback
ply_k WM iM M A*kam e14,�iR�S.cf�1Ld
"Mwasam a illhk Cww Mw
M wawwr []>waatland dA/ta h tad Q ftvm
nlElnllolslsltmrf .� __.IL ts,t.r s!>oMITIAM .araM am
QiIMfNLL'E1t39tlatrAA.B Saf1L-Q CJrtt au'kc
taYtaI ?I_ .__w U-U- tsrso _ t .x _. ._ trsfrPlv4lti•Via: . P _=
padtsEaTb ,�ara aaadlel.-_�.� aim 6= Tim P;amd Na.OU46t4 l
Wwadians LjVkV
F7=!
meataft alli% mmo% rtsrsw.dwatitiad Aawtdnaa
ho,"Jit b_k naaLtagsa�_--Ma:%n a I `seon inns®iloir+lar)a�ir.s�w
tnaA SROlfO
wsaaft;JL_+L2ff ati _a assOr �t —` 35
ar." ""•IstaMa it. ss tL OsAtetawaenilis�r Is >d
la.INrsawprb►. v, L�„ sre arP..an.e
Mznnals pkced iam n w _ a
sa,f.�a sad: p ves 0 No 7o-ha dnpll7 20
N.ieriel uuJmsed Betonde
W.nv wr.ra IWAMa Mbk wain! i1 V. ®R me .
type nt wwq t ._.- _.. 'Rph n t m.la �.-_ -•-.• _ �,.Q--
•pWsk'serat'kkekrvr's Naala .�.:..� .' .
NIR1alLNRiR uws.siwoaaurarawmesemsnK _.__._.._i
soft assl t� awsasaptatao awa .-._--
' aa.aia.Farara.�a.�..J►Wr«aasair uae -
Arr�a.awk.anweawdy kaR.ahnl.wS
WILL TESTS.,n,.wdow.n.moot wren kvd is 1+and btlaw Mw lesd ,
W as a pomp w.r male' ❑ Yn ❑No If ye;by whomn
Ywld._plhrn.wwL _It&..down after —ha
Yield a ilmr w.b n 4n.y—ner Ar.
TLYC_Laa,Ma,1Y E,rloawrM.c.fLs`®nit
d1�1�.1arMlala'sis W�Ap i31lMS ems°{W 7I►V lL6ffi.�Ia�RM M�
Nanlrllra �-
!�ter•taw� M�llasial��•+Y�ffia/RI Iss
�dNLEtta •_,isaaatltMnfit�utaa a+�r aaa. ._
'Fh:4,M1a9saa„„�•^w,ll�ta t� i ..a
�Ttz ohtrs-�.A Mnal�lial faamiaf rs vat A 7ia 1 f11CZt�G
WELL CORSTRI.KTOKCENTIFTCAT10N:I construcaed and/or accept responsibilk-ro,comM tion of this weft,and Its compl'ttmce wKS all t¢'ashington ur.0
consovclion slarldafds Matena'.s used and the information reported above am trot to my best kmwleJle and beiwf.
pordicrpEntim rOTfio t Name(P—)Matillenro.pen INdhngcompmy Davis Drilling
UrJla/GnawreerlTrautee Slsno we ' Adimsa 740 NE Davis Farm Rd.
TlnTausmrwLfaaiosMa ckxuft 4 WA 9b�
:F-rimem omwil Llsawwaxe
ECY OSO.1-20(Rev Odrrid)lfyoa Med 1lua dorw m m as alrena*forma,pima ta!!fit Warer ktiowaa Program of 360-d07.66M
Pei—u wok i.A—'ks,—all 711 few Waskiftian Re/m•Smhe Persona wlri a apretR dr'.abilny tan toff 877.833.6311.
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).
Temporary and/or permanent erosion control measures may be required for any site when land
disturbance is involved. 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 conditions and planned disturbance of this Project include wind-borne silts during dry
weather, and sediment transport during vrolonged wet weather. Sediment transport of disturbed
r
5.0 CLOSURE
Based on the project information 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. Therefore, it is recommended that
Envirotech is promptly notified if project and subsurface conditions found on-site are not as
presented in this report so that we can re-evaluate our recommendations.
This report presents a geological/geotechnical assessment,and is intended only for the owner,or
owners' representative. Furthermore, this report is only valid for the project information and
location described herein.
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 Smith,M.S. Michael Staten,P.E.
Staff Geologist Geotechnical Engineer
Envirotech Engineering Geological Assessment
PO Box 984 page 11 Parcel 22325-44-91090
Belfair,Washington 98528 Mason County,Washington
Ph. 360-275-9374 July 23,2020
APPENDIX A
SITE PLAN
tis
SCALE, 1 INCH=50 FEE
0 25 50
APPROXIMATE
TOP OF SLOPE
EXISTING
DRIVEWAY
31%±
L
PO
PROPOSED SINGLE
PO FAMILY RESIDENCE
34%±
L
PO
PROPERTY LINE
4%±
L
30%+
T.,
PROPOSED DRAINFIELD
PROJECT/OWNER/LOCATII7N
SINGLE FAMILY PROPERTY
GEOLOGICAL ASSESSMENT
KEESLER
1473 ME VJUION CREBL Rll
I RIVE VCIW t VEAE F$LTI NEMIAW RY OM`,1I10TEM AW C8 RMcl.1 t' ik-71890
E nwmA1Rn rm A RME LIDAR 9DL1R➢CC VHEDS AFf3dWgIATC PVAKN=4" yAlww=
P.'R>PF FOM ON THIS=Tr-'LAM VL L NUT PWVAL@ AY A L M LL�� T*
RYIVEM LWkTllU DF ATTE FE AN.ATIM3 A GEOLMIA1_ XAMIRFACE
j TMKZ AS 7HDVti HENE.VTTH FkELhTTDH TOHE 1'TROr�LMU P111X�4 ENiRIE�IR1
OX 204
"JOT IF WAIF? w 1w F%WX fw am=w�mIm ...�..SLM'r ipntycT111R � VR�ID[TOro
urcool3ormw r4rm Be91 TW fEOTrj3fm:L!�mC W AL IEM7 t�
ma
10.4E ON gPaA 7x AIM 4P MM 9,10MA E FEATIMEi 7HAT WAY PO FQ= �A
OFFOFFm�rrr aLEar 'ao°iT�I aaT " Y TFt I-Ert Pr SITE PLAN
APPENDIX B
SOIL INFORMATION
TEST PIT LOG
TEST PIT NUMBER TP-1
PROJECT: SFR Geological Assessment DATE OF LOG: 07/14/2020
PROJECT NO: 20118 LOGGED BY: MCS
CLIENT: Keesler EXCAVATOR: N/A
LOCATION: Parcel 22325-44-91090 DRILL RIG: None
Mason County,Washington ELEVATION: N/A
INITIAL DEPTH OF WATER: N/A FINAL DEPTH OF WATER: NIA
STANDARD PENETRATION TEST
SOIL STRATA,
DEPTH SAMPLERS USCS DESCRIPTION LL PI CURVE
AND TEST DATA DEPTH N 10 30 50
0
O GP Poorly graded GRAVEL with SAND
00
t 00
0
0
2 00
00
0
3 SP Fine SAND
4
5
Excavation terminated at approximately
5 0 feet
6
7
8
9
10
No Groundwater Encountered ENVIROTECH ENGINEERING
This infonnabon pertains only to this boring and should not be Geotechnical Engineering
interpreted as being rndrerin a of the entire site.
Map Unit Description:Everett very gravelly sandy loam,8 to 15 percent slopes--Mason
County,Washington
Mason County, Washington
Eh—Everett very gravelly sandy loam,8 to 15 percent slopes
Map Unit Setting
National map unit symbol: 2t62b
Elevation 30 to 900 feet
Mean annual precipitation: 35 to 91 inches
Mean annual air temperature: 48 to 52 degrees F
Frost-free period: 180 to 240 days
Farmland classification. Farmland of statewide importance
Map Unit Composition
Everett and similar soils: 80 percent
Minor components: 20 percent
Estimates are based on observations,descriptions,and transects of
the mapunit.
Description of Everett
Setting
Landform: Karnes,eskers,moraines
Landform positron(two-dimensional), Shoulder,footslope
Landform position(three-dmensional): Crest,base slope
Down-slope shape: Convex
Across-slope shape: Convex
Parent material: Sandy and gravelly glacial outwash
Typical profile
Oi-0 to 1 inches: slightly decomposed plant material
A-1 to 3 inches. very gravelly sandy loam
Bw-3 to 24 inches. very gravelly sandy loam
Cl-24 to 35 inches: very gravelly loamy sand
C2-35 to 60 inches: extremely cobbly coarse sand
Properties and qualities
Slope. 8 to 15 percent
Depth to restrictive feature: More than 80 inches
Natural drainage class Somewhat excessively drained
Capacity of the most limiting layer to transmit water(Ksat). High
(1.98 to 5.95 in/hr)
Depth to water table: More than 80 inches
Frequency of flooding: None
Frequency of ponding: None
Available water storage in profile Low(about 3.2 inches)
Interpretive groups
Land capability ciassification(irrigated): None specified
Laird capability classification(noninrigated): 4s
Hydrologic Soil Group: A
i Wn Natural Resources Web Soil Survey 7712__
i Conservation Service National Cooperative Sal Survey Page 1 of 2
Map Unit Description:Everett very gravelly sandy loam,8 to 15 percent siopes---Mason
County.Washington
Forage suitability group Droughty Soils(G002XN402WA),
Droughty Soils(0002XF403WA),Droughty Soils
(G002XS401 WA)
Hydric soil rating: No
Minor Components
Alderwood
Percent of map unit 10 percent
Landform: Ridges,hills
Landform position(two-dimensional): Shoulder
Landform position(three-dimensional) Nose slope,talf
Down-slope shape Linear,convex
Across-slope shape: Convex
Hydre soil rating: No
Indianola
Percent of map unit 10 percent
Landform: Eskers,kames,terraces
Landform position(three-dimensional) Riser
Down-slope shape: Linear
Across-slope shape: Linear
Hydric soil rating No
Data Source Information
Soil Survey Area. Mason County,Washington
Survey Area Data: Version 16,Jun 4,2020
i sim Natural Resources Web Sod Survey 7r22r2020
i Conservation Service National Cooperative Sal Survey Page 2 of 2
WATER WELL REPORT
ECOCOLY odMdillr ca",Etaklly,2"o'vy...7"eavy•Aelw CURRENT j
ConsfauctionlDecoraaaaaisabn("a'in circle)
NoticeoflndentNo.W 249645
X Construction Unique Ecology Well ID Tag No.ALH 618
Decommission ORIGINAL INSTALLA77ON Water(tight Permit No.
Notice o(Intent Number
raorostous[ tbmettrc []Ina at.,l ❑A1nacalwl 1 Pmpen Ow,`sr Name Barbara Loudenback
�Y'R(:a...r.. ❑iwa y,.Y ❑� j Wail Sasses Addaeaa is AS M Caeak.LtrS
tflMIIIdWDala t?ar,®Maaoavadaas4QPaaaat tSsealter CW ails' C." gull
llYueaaU 'r3 ttwnaa;Xtiarad r7os ❑OLIN and LavAwx_:xu4sF as*
1e61,a•SIMRTXN Ikl«'07 aSit
an
Lt11tWtYs.3:ItBIEICex`!►>aY LditiLvng La Lug La Milksm
l.us_g L! L+mdd grlai8w
4 IL T=elArcA No. ;123ZWW11
igEe�le`I�are lYeai�Ae�raiSai�IMr,areErirfal aeia�teS mt Aagta/d
fir izfs Y.eelri.r�ei Ilwa L• a °d°"yaN"�'Irs`ie'eIE1aw1.>�Is •lr�u�l �awair•ikas,ga
fnl� momIrlrle
1dloAatledlalMieei 2
:yen Rd�■1� gte81111a
gfea. fts"M ilia. Im g ataTiY 4
Gb_ __--_---moosr !te ; Ne11rt1afaamamA3 de111r li 9}
teraMlpeee•pwgalE' Yn Y vrr Naa d®a.aibnd
lsla<riilt placed Ban it.to
S.,f—Saal: ❑a Yes ❑No "I o who deph?L0__a.
,l.u.�il owsi is sd Bctonile
Did am araa tassel avaugle water+. -_—I!n [] No _
eUnh'dmfsa6tWtW �—•.• �.—�
•au9ar>V1ba1RWaYW'aN#9M ' :.,,..dam. _�. �.
typa" ..Its•. -..
}aMURUlLari6atlMalYlrltlalFaa�aat
alatbataA l� t1WtWt+galwd f>.a ._. _.._�
` r,laa,.r.rtaa-----..patr*talaalaaa tra _
Aweian.awa aawradNd y fa+►."dew de.S
WELL TESTS:rkawdown is amoam wrier Iced it k—W Odow watw•kad ,
Wasapampww nude, ❑ Yn ❑No Ilycr.aY whom+ __
Y.W. P11—.wwh fl rhewdown vfler _ht
Y.M.—gdlmm.with_ fl Jay.d�wn oacr hr..
TIgC gttaaaLtaagiW
&,alra+.emaca/A,w ,aaa
Katsr!6 Rt8 taifatiavfaeaaletaafAmtatY 1 '
Ttaaa zod 'Er vfdv%.:a1 Thas YWGa1N.
wbrTA24 gyunihi6vAbs BardlaAe8ar1 leg
.+pats . atAta�re�Y>V .tip eaa
A 4�.Vi4s.—sson Abe
ea,w treetaot+xre wav*n daatlht mag C 1M K 35a i TNiuS/7fl C'Asolpie�d 6]nIR
WELL COWS71mlfTIRM CERTIEICa♦TIM:1 rotWrucied andtor accept respom;*A p•ror cnnstrucdon or thts weft.and its compliance mth ell Wazhingrnn-Wl
consirttcuon standazds Materials used a nd dw information reported above arc true to my lest ktwwledge and beimf.
0IhtllciD bitimeer❑Trainee Name(a—)Man ennmgsen Drdhng Company Davislhilling
Drilkr/GngmeerlRanec Stgrtalwe Aw,css 340 NE Davis Farm Rd.
Dn'AeraeuelameLbianaft �7 C*'31+%ft errs WA 9f7><
tFTRAfmDaitlat'laul NC
DAVIM110M Oer W62011 I
ECt 030.1-20(Rn ftW8j 1f)aa Bred Ow docwnasm in m aftenaar)brmo,pleats sad/the Water Rmwert Program as 36r,407-66W0
Pertetu with Aaansq low em call 711 for WaaskgVi s Rehn.Serrke Persana with a speech desabrAry can toll 877.833-6341.
(6) An opinion on whether the proposed development is within the landslide hazard area or its associated buffer or
setback and the potential for landslide activity at the site in light of the proposed development.
Located on page(s) 8
TABLE OF CONTENTS
1.0 INTRODUCTION.................................................................................................................................
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
2.3 SURFACE DRAINAGE..........................................................................................................................3
2.3.1 Upland Water Bodies.................................................................................................................3
2A SLOPE AND EROSION OBSERVATIONS...............................................................................................4
3.0 SUBSURFACE INVESTIGATION.....................................................................................................5
3.1 FIELD METHODS,SAMPLING AND FIELD TESTING.............................................................I.............5
3.2 GEOLOGIC CONDITIONS....................................................................................................................5
3.3 SPECIFIC SUBSURFACE CONDITIONS.................................................................................................6
3.3.1 Groundwater............................................................................................................................... 7
4.0 ENGINEERING CONCLUSIONS......................................................................................................8
4.1 LANDSLIDE HAzARnc.........................................................................................................................8
4.1.1 Landslides and Slope Stability Analysis....................................................................................9
4.1.2 Surface and Subsurface Drainage............................................................................................ 9
4.2 EROSION HAZARDS............................................................................................................................9
4.3 SEISMIC HAZARDs.............................................................................................................................10
4.4 OTHER CONSIDERATIONS.................................................................................................................10
5.0 CLOSURE.................».................................».................................................»....................................11
Appendix A-Site Plan
Appendix B-Soil Information
1.0 INTRODUCTION
Envirotech Engineering, PLLC. (Envirotech) has completed this geological assessment for a
residential property located at 1473 NE Mission Creek Road,identified as parcel number 22325-
44-91090 in Mason County, Washington. As presented herein, this assessment 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 soils descriptions in the
Subsurface Investigation Section; and, assessments for landslides, erosion, seismic hazards, and
other considerations in the Conclusions Section.
An initial geological/geotechnical evaluation of the project was conducted by Envirotech on July
14, 2020. It was determined that natural slopes between 15% and 40% were present within 300
feet of the project. Due to these slope grades, a geological assessment is required pursuant to
landslide hazard areas of the Mason County Resource Ordinance(MCRO).
During the evaluation and site visit by Envirotech, surface and subsurface conditions were
assessed in order to determine if further geotechnical studies are required.After completion of the
field work and applicable Project research,Envirotech prepared this geological assessment.
1.1 Project Information
Information pertaining to the project was provided by the proponent of the property, and
observations from a field visit by Envirotech.The proposed development is expected to consist of
a new single family residence, on-site septic system, and other ancillary features typical of this
type of development. Approximate site development with relation to existing site features are
illustrated in the Site Plan in Appendix A of this report.
1.2 Purpose of Investigation and Scope of Work
The purpose of this geological assessment was to evaluate the project in order to confirm that the
proposed development is outside of any landslide hazard area and its associated buffers and
setbacks as determined in the MCRO. The investigation included characterizing the general
project surface and subsurface conditions,and evaluating the suitability of the soils to support the
planned site development. In order to fulfill the purpose of investigation, the geological/
geotechnical program completed for the proposed improvements of the Project include:
• Review project information provided by the proponent of the project;
• Conduct a site visit to document the site conditions that may influence the construction
and performance of the proposed improvements;
• Define general subsurface conditions of the site by observing soils within test pit
excavations, review well logs from existing wells near the Project, and evaluate
geological and hazard maps depicting the site geology for the vicinity of the project;
• Perform soils testing,such as visual classifications,to determine selected index properties
of the soils;
• Complete an engineering assessment supported by planned site alterations and the surface
and subsurface conditions that were identified by the field investigation, soil testing, and
applicable project research;and,
• Establish engineering conclusions based on findings and anticipated development.
Envirotech Engineering Geological Assessment
PO Box 984 page 1 Parcel 22325-44-91090
Belfair,Washington 98528 Mason County,Washington
Ph. 360-275-9374 July 23,2020
N i
A f
_ f
Z
s: Project � h "�
f iY
Seffair
•i"ill`%r'1 � f
— i
yi' f
n
s
ref f
f 3:
Betas t' f
Jtab Fae.. /
N �
i
tmi
LL
Vicinity Map from Mason County Website
Envirotech Engineering Geological Assessment
PO Box 984 page 2 Parcel 22325-44-91090
Belfair,Washington 98528 Mason County,Washington
Ph. 360-275-9374 July 23,2020
2.0 SURFACE CONDITIONS
Information pertaining to the existing surface conditions for the project was gathered on July 14,
2020 by a representative with Envirotech.During the site visit,site features were documented that
may influence construction or reveal potential geological hazards. This Surface Conditions
Section provides information on general observations, vegetation, topography, drainage and
slope/erosion conditions for the project and surrounding areas.
2.1 General Observations
The property currently has an existing mobile home, driveway, other typical features and is
surrounded by residential development. The site is partially cleared. Vegetation on and near the
property consists primarily of firs, maples, 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 for an illustration of the general slope indicators with respect to the planned
development.
Descending slopes exceeding 15% are located on and beyond the property. Average slope grades
are approximately 35% with a vertical relief of approximately 30 feet. The top of slope was
slightly over-steepened from a small amount of fill and brush.
2.2.1 Upslope Geomorphology
Ascending grades are generally located to the east of the planned development. This
slope is relatively minor within 300 feet of the Project, with no apparent slope grades of
at least 15%. The upland area of the property is situated on a hillside and crest.
Landforms are primarily of glacial origin with centuries of weathering overburden.
Additional geomorphology that is pertinent to both upslope and downslope areas are
provided in the Subsurface Investigation Section of this report.
2.3 Surface Drainage
The majority of the stormwater runoff originating upslope from the anticipated development is
expected to be minimal to moderate. Significant scour, erosion and sediment transport was not
apparent near the project where development is expected.Mission Creek is located near the slope
toe,and has normal scour.
2.3.1 Upland Water Bodies
There are no apparent water bodies or wetlands located upslope from the planned
development that would significantly influence the Project.
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2.4 Slope and Erosion Observations
The existing moderate slopes 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 or naturally 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.
The above mentioned indicators, or other signs of 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.
N
t � �!
}
Aerial Photo from Mason County Website
Envirotech Engineering Geological Assessment
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Belfair,Washington 98528 Mason County,Washington
Ph. 360-275-9374 July 23,2020
3.0 SUBSURFACE INVESTIGATION
Information on subsurface conditions pertaining to the project was gathered during research and a
site reconnaissance. The site visit was accomplished on July 14, 2020 by a representative with
Envirotech. Specific information on field methods, sampling,field testing, subsurface conditions,
and results from soil testing are presented in this section of the report. Appendix B has pertinent
information on subsurface conditions for the Project,including test pit log(s)representative of the
site soils,and water well report(s)originating from the subject property and/or nearby properties.
3.1 Field Methods,Sampling and Field Testing
Information on subsurface conditions for the Project was accomplished by probing anticipated
foundation areas with hand tools, and observing soils within test pit excavations and/ or earth
cuts. Information on subsurface conditions also included reviewing geological maps within the
Project vicinity, and water well reports originating from nearby properties. No soil samples were
collected for this Project.Envirotech measured the relative density of the in-situ soils by gauging
the resistance of hand tools.
3.2 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. Hehemann, Isablle Y. Sarikhan,
and Robert L.Logan,July 2009,provides the following caption(s)for the project area:
♦ashon recessional outwash--Gravel and sand;locally includes silt or
clay.tan to gray:rounding and sorting divwse.but most commonly
subrounded and moderately sorted:stratified and loose.ranges from a few
feet to a few teas of feet thick but may locally mceed 100 ft along:4fission
Creek:deposited by Vashon meltwater m oumash channels or isolated
basins;generally less compact than adsance outwash(unit Qga).but in
some exposures difficult to distinguish from unit Qga where not separated
by till:stratigraphically o%whes till.Most deposits of this twit are
ice-proxmal and difficult to separate from unit Qgic.locally resulting in
gradational boundaries and poor distinction between units Qgic and Qgo
(and subunits).This difficulty is illustrated for instance.by a"leaping"
outwash channel(Fig.2).Locally dnided into:
Envirotech Engineering Geological Assessment
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Belfair,Washington 98528 Mason County,Washington
Ph. 360-275-9374 July 23,2020
a �uvium—Silt,sand.and graveL clasts typically well rounded:typically
O y
well sorted and loose:stratified to massiveh-bedded.deposited in stream:,
and adjacent banks.The sediment source is most commonly reworked
recessional outwash ablation till,advance ouhsash and(or)
glaciolacustrine deposits.but may include lodgment till.nouglacial
deposits.and bedrock.Exposures locally resemble the umt's sediment
source units,a particularly notable feature in the Union River valle%.
where the unit is mostly derived from glaciolacustrine and(or)ice-contact
deposits(units Qgof and Qgic).Shear-cave velocih profiles confirm-
however.that trait Qa forms a more diverse deposit than unit Qgof and at
least some deposits of unit Qgic(Fig.4). Subunit Qoa is older alluviums
that resembles trait Qa in every way bin forms elevated relict terraces-
Most appear to be tied to an elevated base level that pievaded prior to a
local base-level lowering events)(see discussion of elevated terraces
under Structure).Where unit Qoa is correctly identified along the tower
reaches of streams that are graded to sea level the age of unit Qoa should
not exceed about 6.000 years because prior to that,sea level was
significantly lower,which likely resulted in an erosional setting that
precluded deposition of alluvium,As mapped,the unit is generally
Holocene but may locally include some unrecognized recessional ournash
terraces(unit Qgo)and other late Pleistocene deposits.A map boundary;
mismatch with the Vaughn quadrangle to the south resulted where Logan
and%lMsh(2007)limped unit Qoa into unit Qa.Elsei%bere.the contact
between unit Qa(this map)and traits Qgt and Qaf(Vaughn quadrangle)
iv as so close to the map boundary that map scale did not permit separating
the geologic boundaries from the map boundary
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 described utilizing the Unified Soil Classification System
(USCS). Using the USCS in conjunction with estimated relative densities and other anticipated
engineering properties of the soil, susceptibility for potential landslides, erosion and seismic
hazards may be assessed.
The project is primarily composed of undisturbed, native soils, without indications of substantial
fill. Competent bearing soils were encountered at 12 inches below the existing native ground
surface in locations where the ground was probed. For engineering purposes, these native soils
consist of distinguishable layers,as presented below.
Soils within the upper 3 feet of natural ground were observed to be primarily poorly graded
gravel with sand(GP). Soils below the upper GP layer were observed to be a fine sand(SP)to a
depth of 5 feet.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(SCS),the site soils are described as Everett very gravelly
sandy loam, Eh, with 8% - 15% slopes. See the soil map below, and the applicable SCS soil
profile(s)in Appendix B of this report.
Envirotech Engineering Geological Assessment
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Belfair,Washington 98528 Mason County,Washington
Ph. 360-275-9374 July 23,2020
r
44 4ef Ink,
410,
INC.
O ® 1D M1
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 50 feet below the current ground surface. Surface seepage or perched
groundwater at shallow depths was not observed on-site, nor indicated on the well
reports. However, some seasonal groundwater is expected to flow directly above the
hardpan on occasion.
Envirotech Engineering Geological Assessment
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4.0 ENGINEERING CONCLUSIONS
The following sections present engineering assessments and conclusions concerning the project.
These conclusions have been made available based on the planned construction activities as
outlined in the Introduction Section of this report; general observations of drainage and
topography as summarized in the Surface Conditions Section; and, soil conditions that were
identified by the field investigation and soils testing as outlined in the Subsurface Investigation
Section. Conclusions for the Project that is provided herein, includes pertinent information for
landslide,erosion and seismic hazards.
4.1 Landslide Hazards
For the planned development, as provided in the Introduction Section of this report, it is
Envirotech's opinion that the proposed development is not subjected to or cause adverse impacts
to a landslide hazard area or its associated buffer or setback as defined in the MCRO. This
conclusion is based on the contents provided in this report.
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.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, excessive and/or repeated surficial slope
movements, if not repaired, may represent a threat to the structural integrity of the slope.
Maintenance of the slope should be completed if the situation does arise in order to prevent the
possibility of further surficial or deep seated slope movements that may be damaging to life or
property.
According to the Department of Natural Resources (DNR) "LHZ—Final A-1 Map— Landslide
Inventory—Mason Watershed,by Sarikhan,et. al., May 2007,"previous landslide activity is not
recorded near the project. Per the Resource Map from DNR, the Project is not within terrain
labeled `highly unstable' or `highly erodible' relating to soils. DNR labeled portions of this
project as medium to high slope instability with relation to slopes. This delineation is primarily
dependent upon slopes and convergence. Secondly, lithology and precipitation are modeled
within this delineation. In summary, this designation is based on mapping without field
observations or knowledge of the specific site geology or soils. A resource map from DNR is
provided below:
Envirotech Engineering Geological Assessment
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Belfair,Washington 98528 Mason County,Washington
Ph. 360-275-9374 July 23,2020
N tl•Wr
11P/1-
H C
f� % w■
■�'i+. ^aR, AIR w■'R, ��' .
a
Rw
R
n
4�
• ii"iJ Project
AL
i
l �
• � / 1 1 �.Rar� �r,.v
r-iy Soils 5
a.r Ja a—
1 /•� Hydnc Sods
• 'w Highly Unstable
• � 1 ■7 I.
[AHiyhly Erodible
•f / ■. /u■/ i R No Data or Gravel Pits
` ■why/• \�. i R./ Slope Stability-West
a•a R■ R ■ EJ la;derate slope Instao,w,
50d ■ ■ High Slope Instability
t:9,028
Map from Washington State Department of Natural Resources Website
4.1.1 Landslides and Slope Stability Analysis
Past landslide activity or high slope instability indicators near the proposed development
was not revealed during the project research.In addition,detrimental landslide activity or
potential high landslide indicators were not observed during the site visit as outlined in
the Surface and Subsurface Conditions Sections of this report. Due to these factors, and
existing/proposed conditions,a slope stability analysis was not deemed necessary for this
project. Considering the planned construction as summarized in the Introduction Section
P J g
of this report; the aforementioned surface and subsurface conditions for the project; the
slope stability assessment provided herein; and the Engineering Conclusions provided
later in this report,it is our opinion that the project is not within a landslide hazard area,
and that the proposed site alterations will not encourage a landslide hazard.
4.1.2 Surface and Subsurface Drainage
This project does not appear to experience significant subsurface drainage or surface
runoff. It is our opinion that groundwater or surface drainage is not a limiting factor for
this Project.
4.2 Erosion Hazards
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
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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 eater .
Z�' (Kc)
Temporary and/or permanent erosion control measures may be required for any site when land
disturbance is involved. 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 conditions and planned disturbance of this Project include wind-borne silts during dry
weather, and sediment transport during prolonged wet weather. Sediment transport of disturbed
soils could be from stormwater runoff or tracking off-site with construction equipment. Although
an engineered erosion control plan is not warranted for this project, Best Management Practices
(BMP's) should be employed during and after construction. Ordinary BMP's includes silt
fencing,protection of drainage outlets and vegetating denuded areas.
Erosion control information and specifications may be found in the applicable "Stormwater
Management Manual for Western Washington,"prepared by the Washington State Department of
Ecology Water Quality Program.
4.3 Seismic Hazards
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.
There are no known faults beneath this project.The nearest Class `A' or V fault to this property
is the Tacoma Fault Zone. This fault is a Class `A', and is located approximately 5 miles to the
south of the Project. This information is supported by the USGS Quaternary Fault and Fold
Database for the United States.
The potential for liquefaction and other earthquake induced hazards are believed to be low for
this project. This is based on subsurface conditions such as soil characteristics and the lack of a
permanent and substantial shallow water table. Subgrade characteristics that particularly
contribute to problems caused by seismic events include submerged and confined, poorly-graded
granular soils. Although gravel- and silt-sized soil particles could be problematic, fine and
medium grained sands are typically subjected to these types of seismic hazards.
4A Other Considerations
It is our understanding that the home will be over 30 feet from the top of slope. If this is not the
case,Envirotech should be notified in order to provide additional recommendations due to the fill
soil. Conclusions in this report are based on the type and location of the anticipated development,
and existing on-site and off-site conditions. Site development that significantly deviates from the
anticipated improvements presented in this report, or nearby development that influences this
Project may require geotechnical design recommendations.
Envirotech Engineering Geological Assessment
PO Box 984 page 10 Parcel 22325-44-91090
Belfair,Washington 98528 Mason County,Washington
Ph. 360-275-9374 July 23,2020
5.0 CLOSURE
Based on the project information 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. Therefore, it is recommended that
Envirotech is promptly notified if project and subsurface conditions found on-site are not as
presented in this report so that we can re-evaluate our recommendations.
This report presents a geological/geotechnical assessment, and is intended only for the owner,or
owners' representative. Furthermore, this report is only valid for the project information and
location described herein.
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 Smith,M.S. Michael Staten,P.E.
Staff Geologist Geotechnical Engineer
Envirotech Engineering Geological Assessment
PO Box 984 page 11 Parcel 22325-44-91090
Belfair,Washington 98528 Mason County,Washington
Ph. 360-275-9374 July 23,2020
APPENDIX A
SITE PLAN
A
SCALE, 1 INCH=50 FEE
0 25 50
APPROXIMATE
TOP OF SLOPE
EXISTING
DRIVEWAY
31%±
L
ASINGLE
PO
34%±
L
PO
PROPERTY LINE
4%±
30�+
TPI
PROPOSED DRAINFIELD
PROJECT/ OWNER/LOCATIDN
SINGLE FAMILY PROPERTY
GEOLOGICAL ASSESSMENT
KEESLER
1173 HEKIWON U EEK 08
lOT�DCX4T3K A1E8 FSLII XE.A31IU RT DrfVI�AW CA pArga BESE!F 90
Enw.-doirm rwN A PLwLIC LID"ImjK£Wow AP69DPRIATE @Mm Cmuff,YAIDQ( m
}11
-4Jl ."ON INV Xa E:"LAM MEN P$tt PWVJL4 3Y A L Ti Ll:brmil_1IlV YDR.LIC.A.TIIM DF XTE MAnAlE3 ANC 6ID1.30CSA_,/3Ul WAGE
3=MATIMM 64$MWY HERE,bfM KELATTDIH 71I TiE POOMM LMM EMYINANECH ENNOWEIONIS
A-I%T YEF MJFIF]VV TW fMfV,TIE A1lRJ.=10 AND _ 44-3Lw'I'lXM'Mt AO 46
ffcnw)ThmA-mw P::XNnYFA IN TFf I�E•OTEC K IMAL/SAL rdmvy $LFi'F.L.17..VA3HD3f70h1
AAF.AP-rF,DX rP'YrIM'.0 KC 3d rUM K,113I'BADE FFATLKE%7FM.T RAi Po PR03C Slfi1r0;75-9aY4
:AE LDI'A p DN PNC DFF TFE PDII.^1",AR3 AN%nT WUZTXXADLsr
1RSED O%F DF P%0VtrY LAU SHOW OX TIO SITE.", Tmo TEST Pl' SITE FLAN
APPENDIX B
SOIL INFORMATION
TEST PIT LOG
TEST PIT NUMBER TP-1
PROJECT: SFR Geological Assessment DATE OF LOG: 07/14/2020
PROJECT NO: 20118 LOGGED BY: MCS
CLIENT: Keesler EXCAVATOR: NIA
LOCATION: Parcel 22325-44-91090 DRILL RIG: None
Mason County,Washington ELEVATION: N/A
INITIAL DEPTH OF WATER: N/A 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
O GP Poorly graded GRAVEL with SAND
oa
o0
0
0
2 00
LOOC
3 SP Fine SAND
4
5
Excavation terminated at approximately
5 0 feet
6
7
8
9
10
No Groundwater Encountered ENVIROTECH ENGINEERING
This information pertains only to this banng and show not be Geotechnical Engineering
interpreted as being indicitive of the entire site
Map Unit Descnplan Everett very gravelly sandy loam,8 to 15 percent slopes---Mason
Count,.Washington
Mason County. Washington
Eh—Everett very gravelly sandy loam. 8 to 15 percent slopes
Map Unit Setting
National map unit symbol. 2t62b
Elevation 30 to 900 feet
Mean annual rep ftation. 35 to 91 inches
P A
Mean annual air temperature: 48 to 52 degrees F
Frost-free period: 180 to 240 days
Farmland classification: Farmland of statewide importance
Map Unit Composition
Everett and similar soils: 80 percent
Minor components: 20 percent
Estimates are based on observations,descriptions,and transects of
the mapunit.
Description of Everett
Setting
Landfonn. Karnes,eskers,moraines
Landform position(two-dimensional): Shoulder,footslope
Landform position(three-dimensionai): Crest,base slope
Down-slope shape: Convex
Across-slope shape: Convex
Parent material. Sandy and gravelly glacial outwash
Typical profile
Oi-0 to 1 inches: slightly decomposed plant material
A-1 to 3 inches: very gravelly sandy loam
Ow-3 to 24 inches.' very gravelly sandy loam
Cl-24 to 35 inches: very gravelly loamy sand
C2-35 to Winches: extremely oDbbiy coarse sand
Properties and qualities
Slope: 8 to 15 percent
Depth to restrictive feature: More than 80 inches
Natural drainage class: Somewhat excessively drained
Capacity of the most limning layer to transmit water(Ksat). High
(1.98 to 5.95 inthr)
Depth to water table: More than 80 inches
Frequency of flooding. None
Frequency of ponding: None
Available water storage in profile Low(about 3.2 inches)
Interpretive groups
Land capability classification(irrigated): None specified
Land capability classification(noninigated). 4s
Hydrologic Soil Group. A
t si" Natural Resources W'eb Soil Survey 722R020
i Conservation service National Cooperative Sod Survev Page 1 or 2
II
Map Unit Description:Everett very gravelly sandy loam,8 to 15 percent sbpes—Mason
County,Washington
Forage suitability group: Droughty Soils(G002XN402WA),
Droughty Soils(G002XF403WA),Droughty Soils
(G002XS401WA)
Hydnc soil rating: No
Minor Components
Alderwood
Percent of map unit 10 percent
Landform: Ridges,hills
Landform position(two-dimensional). Shoulder
Landform position(three-dimensional). Nose slope,talf
Down-slope shape. Linear,convex
Across-slope shape. Convex
Hydnc sal rating: No
Indianola
Percent of map unit. 10 percent
Landform: Eskers,kames,terraces
Landform position(three-dimensional) Rises
Down-slope shape: Linear
Across-slope shape: Linear
Hydnc sal rating: No
Data Source Information
Soil Survey Area. Mason County,Washington
Survey Area Data: Version 16,Jun 4,2020
i v)A Natural Resources Web Sal Survey 7122rMO
�� Conservation Service National Cooperative Sal Survey Page 2 Of 2
Q WATER WELL REPORT
jEa&Y Gr4onalaf ca"-sty 2"cgq•owtwr,IwumFy-dAaer C1 R R P NT
.�.�... Notice of Intent No.W 249645
ConsftWilonlDecommisabn(Yin circle)
0 Construction Unique Ecology Well ID Tag No.ALH 618
pewrnTission ORIGINAL INSTALLATION Water Right Permit No.
Noticc o0rifent Number
IrlloMslD use: ■t mK ❑Indum,al QpMuiaptl Property Owner Name Barbara Loodenback --�
r_Iaea GaagwwYdell Nwathi;zase ale +wan Geerd.Sld
IIVs 1Mt1om0=1 8mairetwtfJl"ea*-we �#11(Ys!
M univwl c afaasim" maw. C oft 0 al.
F tumlbo.._M_V4,t .:A SwV_ .A3_.r oOs*
am
LSAMDriL'ilr4allRt'An.S I,elGtLwTag Lilt Lrc��ltr'�Rx:
an tl.ls .:
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�fl' � Yaraitpi raat ss aL omaeirlaagYfY aftMttlaa� talirYrtlr�reteltArp
ilttslili� ETA b 9%,m Katie tom!_ ll i�lsl/1N�1T)
gstoiaraM1111� 'IfA�ItL �g __
Y
7!a g1�11g 1� IIW1Y Sadr
llts� aaar.� _,,ti..�—.L �as tEeneeua . .t 1� s
(ram 1.1at>m Ir. SLID A
drawNlwbryaebok ova lb
Surface SeJ: Yn ❑No T.Mr depthT (�___a
fN4 my ara.contain u nbk wat«t n Y. [�]No
ryyla,4•w+Mi'T �,�_.. __ "cJaNttRtaaW a�� .-�- _.. _ _ .__..W-
s#eA+lmrewd�.mtaaell
•/taWa:yfdMtraatM'S Idaatp -
tvATtatttRIIa:IsidarasatdwrlrYavartsoa.w:e+ed r.._._...�.IL
�iia rartC��l._....-....,...,..._._i bekw hfi arwvv thva �.. ._._.__.
rom*ioe µvaaea,,,__,�,la Farrrarao Sells tape
Aneaiea w.Ne il.amnrwd ty (eoRwM,ate.) _.__.___��
WELL TESTS:fxawdmvn n amomt weer Iavd is lowered bebw swic level
avne a Pu P tea ovwk' ❑ Yes ❑No If ys1 by whom' —�
Vwtd. pl ltron.waQ _n hrwdown M« _M+.
Ywid. aallmN.with a.thawdown.lk, _h,. _/\r
TWAL_Fetei4.+Y e,dsaiw etmaM.—aY
�tarP�al�,�t�trFR11t>�id��tt�
35e.a TlldRLfY/ 1:� YES vfRtrx F•1ath(�0�
-
.g��g1i4 iFlieb.tdia�,�-•tdlalaa�l 111a
ftngre ,�rtant av>?',ra• ,.t. L4P WL -
LTw.«#siawaotaie�,� a: ard:+tdaittttteritttttlrl 1J van K 14
WEEL CERTTFlCAT1UN:f constrtrcied andWf xcctx fesponlDdhy fbr comarmilon of Tlifs welt.and fts campliame With all WJsittngton weft
construction siandwds Materials used and the information reported above are true to my beat knowledge and belief.
1]DnvletpEngitw C1Tmnee Namc(e,.,)Man temmngsen Driving Compmy Davis Drilling
Dr11Ia/GnginetflTfatmC Signature_ ess AdM 340 NE Davis Farm Rd.
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EC7 050-I-So(Rev oaAs)Ifyoa med this docuixent in an alrenaa format,please call the Water Reaowces foram as JIML4074W,
Permnt with Many less can coif 71I for WasMnytrm Rr*Service Persons with a speech dlsabdgv can call 977-83"34I.