HomeMy WebLinkAboutGeological Assessment for GRD2008-00001 - GEO Geological Review - 5/6/2008 FR E C E I Vlf "l
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CCD - PLANNING
KENNETH NEAL & ASSOCIATES
CONSULTING ENGINEERING GEOLOGISTS
3314 Gibraltar Ct. S.E.,Olympia,WA 98501-3968
Telephone: (360)352-5125 Fax: (360)236-0201
e-mail: kengneal�aJaoLcom was
May 6,2008 a �o
MEMORANDUM
TO: Mason County Department of Community Development
ATTENTION: Robert D.Fink,AICP,Planning Manager Engineering Geolo t
100
FROM: Kenneth G.Neal,L.G.,L.E.G.,Principal Engineering Geologist c��sed
SUBJECT: Review Comments—GRD 2008-00001 KENNETH G. NEAL
"Geological Assessment for S & J Johnson Industrial Property, Parcel No.
12321 34 00030, Mason County, Washington, Mason County, Washington,"
report, dated April 9, 2008, to S & J Johnson, Inc., and "Geological
Assessment Addendum #1 for S&J Johnson Industrial Property, Parcel No.
12321 34 00030," letter, dated April 29, 2008, to S&J Johnson, LLC, both
written by Envirotech Engineering
The addendum letter was written to provide a site plan with a north arrow pointed in the correct direction
rather than east as shown on the site plan in the original report.
We recommend this assessment be approved, in that there was no evidence of slope movement or erosion
identified by the consultant. We did identify several deficiencies in the report that should be noted:
1. The soil classifications presented in the report on Page 6 do not match the percentages provided
with the soil descriptions. Both soils were described on Page 7 as having less than five percent
fines, giving them both Unified Soil Classifications of SP rather than SM.
2. The site plan appears to have been drafted at a larger sheet size and then reduced. This renders
the notations for the test pit locations barely visible, and the symbols used for test pit designation
invisible even under magnification.
3. The property lines on the site plan for the west half of the parcel are, with the exception of the
north property line, incorrectly scaled. Using the 1-inch equals 200-foot scale shown on the
drawing, the west property line measures 778 feet, not the 770.98 shown, and the south property
line measures 512 feet, not 517.18. The locations for building and drainfield placement shown
on this site plan should be considered suspect.
None of these issues adversely affects geotechnical considerations for site development.
If you have any questions, please call. I can most easily be reached on my cell phone at 360-280-6180.
2 copies submitted
KENNETH NEAL & ASSOCIATES
CONSULTING ENGINEERING GEOLOGISTS
3314 Gibraltar Ct.S.E.,Olympia,WA 98501-3968
Telephone: (360)352-5125 Fax: (360)236-0201
e-mail: kengnealaa aoGcom o{
May 6,2008 aye
MEMORANDUM
TO: Mason County Department of Community Development
ATTENTION: Robert D.Fink,AICP,Planning Manager n;inee ,9 , gist
100 x
FROM: Kenneth G.Neal,L.G.,L.E.G.,Principal Engineering Geologist
SUBJECT: Review Comments—GRD 2008-00001 KEN:NETH G. NEAL
"Geological Assessment for S & J Johnson Industrial Property, Parcel No.
12321 34 00030, Mason County, Washington, Mason County, Washington,"
report, dated April 9, 2008, to S & J Johnson, Inc., and "Geological
Assessment Addendum #1 for S&J Johnson Industrial Property, Parcel No.
12321 34 00030," letter, dated April 29, 2008, to S&J Johnson, LLC, both
written by Envirotech Engineering
The addendum letter was written to provide a site plan with a north arrow pointed in the correct direction
rather than east as shown on the site plan in the original report.
We recommend this assessment be approved, in that there was no evidence of slope movement or erosion
identified by the consultant. We did identify several deficiencies in the report that should be noted:
1. The soil classifications presented in the report on Page 6 do not match the percentages provided
with the soil descriptions. Both soils were described on Page 7 as having less than five percent
fines,giving them both Unified Soil Classifications of SP rather than SM.
2. The site plan appears to have been drafted at a larger sheet size and then reduced, This renders
the notations for the test pit locations barely visible,and the symbols used for test pit designation
invisible even under magnification.
3. The property lines on the site plan for the west half of the parcel are, with the exception of the
north property line, incorrectly scaled. Using the 1-inch equals 200-foot scale shown on the
drawing, the west property line measures 778 feet, not the 770.98 shown, and the south property
line measures 512 feet, not 517.18. The locations for building and drainfield placement shown
on this site plan should be considered suspect.
None of these issues adversely affects geotechnical considerations for site development.
If you have any questions, please call. I can most easily be reached on my cell phone at 360-280-6180.
2 copies submitted
Envirotech Engineering
74 NE Hurd Road,
Belfair, WA 98528
April 30, 2008
R CEIVED
Att. James Scholz 'yY i. 1 7(In-8 1
Mason County Department of Community Development
PO Box 279
Shelton, Washington 98584
RE: Geological Assessment Addendum for Parcel# 1232134 00030, Mason County,
Washington
Dear Mr. Scholz,
Envirotech Engineering (Envirotech) has completed comments and revisions to the
referenced geological assessment. Three original copies are enclosed.
Please contact Michael Staten at 360-275-9374 if you have any questions or require
additional information.
Yours Truly,
Envirotech Engineering
7w 5A;
Michael Staten, P.E.
Project Director
OFFICE: 360-275-9374 CELL: 360-689-6045
FAX: 360-275-4789
EMAIL: envirotech@geotechnicalinfo.com
Envirotech Engine Bring Qom,,
74 NE Hurd Road,
Belfair, WA 98528
April 29, 2008
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S&J Johnson, LLC.
PO Box 488
Belfair, Washington 98528
RE: Geological Assessment Addendum #1 for S&J Johnson Industrial Property, Parcel
No. 12321 34 00030, Mason County, Washington
Envirotech Engineering (Envirotech) has completed this geological assessment addendum
for the above referenced property. The original report, dated April 9, 2008, was prepared
by Envirotech (Project #0837). This addendum was prepared in order to provide
additional information requested by Keneth Neal & Associates concerning the project and
the aforementioned geological assessment.
The Site Plan in the original geological assessment depicts an incorrect north arrow and
title block. All directional observations provided in the original assessment provide correct
information. A revised Site Plan is attached to this addendum, and site features with
relation to the proposed development are shown on this Site Plan.
Envirotech is pleased to submit this addendum for the S&J Johnson industrial property.
This addendum provided corrections and/ or additional information concerning the
project. Conclusions and/ or recommendations did not change from the original geological
assessment. Please contact Michael Staten at 360-275-9374 if you have any questions,
comments, or require additional information.
Best Regards,
Envirotech Engineering
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EXPIRES JAN 10,2009
Michael Staten, P.E.
Project Manager
Envirotech Engineering Geological Assessment Addendum#1
Ph. 360-275-9374 Page I of 1 S&J Johnson Industrial Property
Fax 360-275-4789 Parcel 1232134 00030
April 30,2008
ATTACHMENTS
1. SITE PLAN
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PROJECT/ OWNER/ LOCATIONi
S&J J❑HNS❑N
GE❑L❑GICAL ASSESSMENT
SiJ JOHNSON, LLC
PARCEL NO 12321 34 00030
MASON COUNTY, WASHINGTON
ENGINEER
LEGEND ENVIROTECH ENGINEERING
2/* 74 NE HURD ROAD
SLOPE DIRECTION BELFAIR, WASHINGTON 98328
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RECEIVED
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MASON COUNTY
RECEIVED
Geological Assessment MAY 0 7 2008
for NICCD - PLANNING
S & J Johnson Industrial Property
Parcel No. 1232134 00030
Mason County, Washington
April 9, 2008
Project#0837
Prepared For:
S & J Johnson, Inc.
CLYDFST PO Box 488 C�,Pti w,Asy, gT
Belfair, Washington 98528
Prepared By:
Envirotech Engineering �43045� ww�
74 NE Hurd Road �FSS/ 'ISTIE
Belfair, Washington 98528
Phone: 360-275-9374 F EXPIRES JAN 10,200s
Fax: 360-275-4789
TABLE OF CONTENTS
1.0 INTRODUCTION...........................................................................................................................1
1.1 PROJECT INFORMATION............................................................................................................... 1
1.2 PURPOSE OF INVESTIGATION........................................................................................................ 1
1.3 SCOPE OF WORK........................................................................................................................... 1
2.0 SURFACE CONDITIONS..............................................................................................................3
2.1 GENERAL OBSERVATIONS............................................................................................................ 3
2.2 TOPOGRAPHY...............................................................................................................................3
2.2.1 Upslope Geomorphology....................................................................................................... 3
2.2.2 Downslope Geomorphology.................................................................................................. 3
2.3 SURFACE DRAINAGE.....................................................................................................................4
2.4 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......................................................................................................................... 6
3.4 SOILS TESTING.............................................................................................................................6
3.4.1 Visual Classification............................................................................................................. 7
4.0 ENGINEERING CONCLUSIONS..................................................................................................8
4.1 LANDSLIDE HAZARDS................................................................................................................... 8
4.1.1 Septic Drainfield Impacts...................................................................................................... 9
4.1.2 Surface and Subsurface Drainage........................................................................................ 9
4.1.3 Off-site impacts................................................................................................................... 10
4.2 EROSION HAZARDS..................................................................................................................... 10
4.3 SEISMIC HAZARDS...................................................................................................................... 10
4.4 OTHER CONSIDERATIONS........................................................................................................... 11
5.0 CLOSURE..................................................................................................................................... 12
Appendix A- Site Plan
Appendix B - Soil Information
Soil Logs
Well Reports
1.0 INTRODUCTION
Envirotech Engineering (Envirotech) has completed this geological assessment for a
partially developed industrial property identified as parcel number 12321 34 00030
located in Mason County, Washington (Project). 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 and seismic hazards in the Conclusions Section.
An initial geological/geotechnical evaluation of the Project was conducted by Envirotech
without the property owner, on April 7, 2008. It was previously determined that slopes
between 15% and 40% were present within 300 feet of the planned development, and
subsequently will require a geological assessment 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. 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 property owner, S & J Johnson,
Inc., and general assumptions typical of this type of development. The Project is accessed
from NE Peninsula Place connecting State Highway 3. See the vicinity map on the
following page of this report. The new development is expected to consist of
approximately 32,700 cubic yards of grading for building pads, access and stormwater
management. Building construction is not anticipated at this time. However, buildings
will be part of the long range development of this parcel. Approximate site development
with relation to existing site features are illustrated in the Site Map in Appendix A.
1.2 Purpose of Investigation
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.
1.3 Scope of Work
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 Project owner/developer;
• Conduct a site visit to document the site conditions that may influence the
Envirotech Engineering Geological Assessment
Ph. 360-275-9374 page 1 Parcel 1232134 00030
Fax: 360-275-4789 Mason County, Washington
April 9,2008
i
construction and performance of the proposed improvements;
• Define the general subsurface conditions of the site by observing several existing
excavations within the Project, and review well logs from existing wells near the
Proj ect;
• Perform soils testing to determine selected index properties of the soils that
includes 2 visual classifications;
• 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.
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Envirotech Engineering Geological Assessment
Ph 360-275-9374 page 2 Parcel 1232134 00030
Fax:360-275-4789 Mason County,Washington
April 9,2008
a,
2.0 SURFACE CONDITIONS
Information pertaining to the existing surface conditions for the Project was gathered on
April 7, 2008 and prior visits by Michael Staten, geotechnical engineer with Envirotech.
During the site visit, site features were documented, soil samples were collected from
This Surface
selected locations, and near-surface soils were visually classified.
Conditions Section provides information on general observations, vegetation,
topography, drainage and slope/ erosion conditions for the Project and surrounding areas
that may impact the Project.
2.1 General Observations
i currently partially developed land as previously mentioned and
The Project s p y ,
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surrounded by commercial, industrial and residential development. A Navy railroad
ROW extends in a north-south direction through the middle of the property. A portion of
the property is used for construction materials such as sand and gravel, another area is
designated as a nursery, and another building used as a mechanic shop, staging and
storage. Vegetation on the property consists of firs, madronas, 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 Project is situated within and near moderate terrain. The topographic information
provided in this section was extrapolated from a public lidar source, and incorporated
observations and field measurements. See the Site Map in Appendix A for an illustration
of the general slope indicators with respect to the planned development.
2.2.1 Upslope Geomorphology
Ascending grades are located to the east of the planned development. These
slopes are generally 10 to 15 percent. Structural fill with approximate 2:1
inclinations exist for the railroad foundation, and the existing building/ parking
foundation. There are no apparent natural water bodies or wetlands located
upslope from the planned development. A retention pond is located to the east of
the railroad, and the railroad embankment serves as a dam with a culvert for
overflow.
2.2.2 Downslope Geomorphology
Descending grades of up to approximately 25% exist near the west property line
in the middle of the property. To the west, this slope ranges from 20% to 25%
with a vertical relief of nearly 200 feet.
Envirotech Engineering Geological Assessment
Ph. 360-275-9374 page 3 Parcel 1232134 00030
Fax: 360-275-4789 Mason County, Washington
April 9,2008
2.3 Surface Drainage
The majority of the stormwater runoff originating upslope from the anticipated
development is expected to be minimal due to the railroad embankment directing water to
the retention pond. Surface water to the east of the railroad appears to mostly sheet flow
towards the west. Excessive scour, erosion or other indications of past drainage problems
were not observed at or near the planned development.
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.
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
Ph. 360-275-9374 page 4 Parcel 1232134 00030
Fax:360-275-4789 Mason County,Washington
April 9,2008
3.0 SUBSURFACE INVESTIGATION
Information on subsurface conditions pertaining to the Project was gathered during
research and site visits on February 26, and April 7, 2008 by Michael Staten,
geotechnical engineer 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 two test pit logs representative of the site soils, and one water well
report.
3.1 Field Methods, Sampling and Field Testing
Information on subsurface conditions for the Project was accomplished by observing
soils within several existing test pit excavations of up to approximately 7 feet below the
existing ground surface. Information on subsurface conditions also included reviewing
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. Field testing results generally indicated loose to medium dense soils in the
upper 12 inches, medium dense soils from 12 inches to 30 inches below natural ground,
and medium dense to dense soils within the testing locations from 30 inches below
natural ground to the depth of terminous.
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.
As previously mentioned, the Project is located in the Puget Lowland with sedimentary
rocks dominated by glacial drift. The NRCS soil type is of the Indianola series, and
according to soil mapping, is considered loamy sand.
3.3 Specific Subsurface Conditions
The following subsurface conditions are estimated descriptions of the Project subgrade
Envirotech Engineering Geological Assessment
Ph. 360-275-9374 page 5 Parcel 1232134 00030
Fax: 360-275-4789 Mason County, Washington
April 9,2008
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 composed of mostly native soils beneath an organic/ soil mixture of about
6 to 8 inches, with indications of borrowed fill. The fill beneath existing building and
parking areas are reportedly structural fill. The fill beneath the railroad tracks that divide
the property is assumed to be structural fill. For engineering purposes, these native soils
consist of distinguishable layers, as presented below.
Soils within the upper 3 to 4 feet of natural ground are primarily moist, loose to medium
dense brown poorly graded sand with gravel (SM) and few silts. Gravels are primarily
well-graded, and subrounded. Sand content was primarily fine to medium, and the fines
content exhibited none to low plasticity.
Soils beginning at 3 feet to 4 feet below the ground surface to an unknown depth is
medium dense to dense, moist, brown poorly graded sand with gravel (SM). Gravel
content is primarily subrounded and coarse. Sand content was primarily medium. Only a
trace of fine soils were exhibited within this strata.
According to the well reports, the sand and gravel soils may extend to depths of over 140
feet below the ground surface.
3.3.1 Groundwater
From the water well report and knowledge of the general area, permanent
groundwater is expected to be greater than 100 feet directly below the property
near the existing building pad location. Seepage or other perched groundwater
was not observed or indicated on the well report. Overall, the upper subsoil
consists of a high permeable stratification due to the soil classification and
relative density.
3.4 Soils Testing
The soil samples obtained at the Project site during the field investigation were preserved
and transported for possible laboratory testing. Visual classification of soils was
performed in the field. The following soil tests were performed in accordance with the
American Standards for Testing and Materials(ASTM):
2 Visual Classifications (ASTM D2488)
Envirotech Engineering Geological Assessment
Ph. 360-275-9374 page 6 Parcel 1232134 00030
Fax: 360-275-4789 Mason County, Washington
April 9, 2008
3.4.1 Visual Classification
The general results from the visual classification are presented above in the
Subsurface Conditions Section at depths of up to 7 feet below the natural ground
surface. Specifically, soils within the upper 3 to 4 feet in many test pits consisted
of approximately 35% gravel, 60% sand-sized soils, and less than 5% silts. Soils
below the previously referenced strata consisted mostly of about 20% gravel, 80%
sands, and 0% to a trace of silts. Minor variations observed during the visual
classification of particle size content (i.e. gravel, sand, fines), or isolated pockets
within the soil stratification were insignificant in relation to the overall
engineering properties of the soil.
Envirotech Engineering Geological Assessment
Ph. 360-275-9374 page 7 Parcel 1232134 00030
Fax: 360-275-4789 Mason County,Washington
April 9,2008
4.0 ENGINEERING CONCLUSIONS
The following sections present engineering assessments and conclusions concerning the
proposed development of the Project. These conclusions have been made available based
on the planned improvements 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
Landslides and erosion are natural processes, and structures near slopes possess an
inherent risk of adverse settlement, sliding or structural damage due to these processes.
These risks cannot be eliminated for any site with moderate to steep sloping grades.
Geotechnical and geological engineering provides an acceptable factor of safety for
building near sloping site conditions. These factor of safeties are based on engineering
judgment, and engineering standards accumulated from years of academic and
professional research by individuals in the field of geotechnical and geological
engineering.
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. With appropriate drainage and erosion control provisions for this
Project during and after construction, it is unlikely that this Project will experience
excessive surficial movements. However, 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.
It is Envirotech's opinion that the proposed development is not within 300 feet of a
landslide hazard area or its associated buffer or setback as defined in the MCRO.
According to the Resource Map from the Washington State Department of Natural
Resources (DNR), the Project is not within terrain labeled `highly unstable' or `highly
erodible' relating to soils. In addition, DNR did not indicated previous landslide activity
near the Project. DNR labeled portions of this project as medium and 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
on the following page of this report.
Past landslide activity near the proposed development was not revealed during the Project
Envirotech Engineering Geological Assessment
Ph. 360-275-9374 page 8 Parcel 1232134 00030
Fax: 360-275-4789 Mason County, Washington
April 9, 2008
research. In addition, detrimental landslide activity was not observed during the site visit
as outlined in the Surface Conditions Section of this report. Considering the planned
construction as summarized in the Introduction Section of this report, it is our opinion
that the proposed site alterations will not encourage a landslide hazard.
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4.1.1 Septic Drainfield Impacts
The approximate locations of the planned septic drainfields are presented on the
Site Plan in Appendix A of this report. The drainfields are not expected to
adversely influence moderate slopes within the vicinity of the septic components.
This determination is partly based on the behavior and characteristics of the
Project soils under saturated conditions, in addition to the relatively moderate
grades located immediately upslope and downslope from the proposed drainfield
locations.
4.1.2 Surface and Subsurface Drainage
This Project does not appear to experience significant subsurface drainage or
Envirotech Engineering Geological Assessment
Ph. 360-275-9374 page 9 Parcel 1232134 00030
Fax: 360-275-4789 Mason County, Washington
April 9, 2008
surface runoff. It is our opinion that groundwater or surface drainage is not a
limiting factor for slope stability for this Project. This is based on the deep, high
permeable soils, topography, and the immediate planned development.
4.1.3 Off site impacts
Potential off-site impacts are limited for this Project. It is Envirotech's opinion
that adjacent properties, both upslope and downslope from the planned site
alterations, should not be negatively impacted. Existing stable slopes, good
stormwater collection systems downslope from the property, and anticipated
stable slopes after construction does not warrant off-site concerns for this Project.
4.2 Erosion Hazards
Based on the USCS description of the Project soils, the upper soils are considered to have
a low erodibility factor. However, due to the excessive earthmoving operation for this
Project, temporary and/ or permanent erosion control measures are warranted. The type
and extents of erosion control should be provided in the stormwater management plan.
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
7 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 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. Significant `submerged and confined' sand stratifications are not
anticipated to be within the upper 50 feet of the subsoils.
Envirotech Engineering Geological Assessment
Ph. 360-275-9374 page 10 Parcel 1232134 00030
Fax: 360-275-4789 Mason County, Washington
April 9,2008
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 a qualified engineer observes and documents the
construction, or 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
Michael Staten, P.E.
Geotechnical Engineer
Envirotech Engineering Geological Assessment
Ph. 360-275-9374 page 12 Parcel 1232134 00030
Fax: 360-275-4789 Mason County, Washington
April 9,2008
r
APPENDIX A
SITE PLAN
SCALE- 1 INCH 200 FEET
00
F�
l�
XISTING ACCESS ROAD
(NE PENINSULA PLACE)
APPRX. \ \ EXISTING
NURSERY
EXISTING SCALE FUSE 2
i
o✓
RE EN��
EXISTIp
RETEN ION
POND
"�rN
•EXISTI N 21, U.S. NAVAL RR ROW
DRALNFIEL 48'
to
DR�AINF LA' EXISTING XISTING L=619.45' R=1229.57'
EXISTBUILDING j CENTERLINE
BUILDDC PROP13SED.1 PRO-=EDP
PARKING PAD Pw
ELEV.-266.0 ELEV-239D
PROPOSED EXISTING 2-1 FILL
DRAINFIELD SLOPES (SEE REPORT)
> PROPOSED 3
BUILDING 83 r
PAD h
ELEV.-24L0
OD OD o a O
y�6g�{ y� O
w
CD 1*P2 _ W n
IJ m
1W
V
ID
n
BUD_DDG H
APPROXIMATE PAD
LOCATION OF ,� ELEv.-224D PROPOSEn
4DFT UTILITY/
AND ACCESS PROPOSED
RETENTION
D POND
ETEN I@! .N
OND ......_
RTY LINE
91
770.98' N 00.57'03'E
PROJECT/ OWNER/ LOCATION,
H❑LMES
GE❑L❑GICAL ASSESSMENT
DAVID HOLEMS
PARCEL NO 22223 51 02057
MASON COUNTY, WASHINGTON
ENGINEER-
LEGEND ENVIROTECH ENGINEERING
27# 74 NE HURD ROAD
_ SLOPE DIRECTION BELFAIR, WASHINGTON 98526
TPI e TEST PIT 360-275-9374
SITE PLAN
APPENDIX B
SOIL INFORMATION
TEST NT LOG
TEST Pff NUMBER TP-1
PROJECT: Industrial Site Geological Assessment DATE OF LOG: 02/26/2008
PROJECT NO: 0837 LOGGED BY: MACS
CLIENT: S&J Johnson EXCAVATOR: N/A
LOCATION: Parcel 1232134 00030 DRILL RIG: None
Mason County,Washington ELEVATION: N/A
INITIAL DEPTH OF WATER: N/A FINAL DEPTH OF WATER: N/A
sTANDNW PENETMTM TEST
STRATA,
DEPTH solL SAMPLERS uses DESCRIPTION LL PI DEPTH N CURVE
AND TEST DATA 10 30 50
0
SP Brawn,moist,loose to medium dense
POORLY GRADED SAND with GRAVEL
and few slits.Gravel Is welHpuded and
1 subrounded.Sand Is primarily mdium.
None to Low plastidty.
Medium Dense
Density Increases with depth
3
Medium sand only
4
5
Excavation terminated at approxdrtelely
52 feet
6
7
8
9
=10
No Groundwater Encountered ENVIROTECH ENGINEERING
Th*M m on pwtaha a*to M ba ft era Mxx&nor be Geotschnical Engineering
lnlerpreerd es eehp(r►dcNJre dme erMlne eMa.
TEST RT LOG
TEST Pof NUMBER TP-2
PROJECT: Industrial Site Geological Assessment DATE OF LOG: 02/26/2008
PROJECT NO: 0837 LOGGED BY: MCS
CLIENT: S&J Johnson EXCAVATOR: N/A
LOCATION: Parcel 1232134 00030 DRILL RIG: None
Mason County,Washington ELEVATION: N/A
INITIAL DEPTH OF WATER: N/A FINAL DEPTH OF WATER: N/A
solL STRATA.
sri NWO PENETMronr TEU
DEPTH SAMPLERS USCS DESCRIPTION LL PI DEPTH ICURVE
AND TEST DATA N 10 30 50
SP Brown,moist,loose tD medNm dense
POORLY GRADED SAND wkh GRAVEL
Gravel Is mostly ooarse and subrounde&
1 Sand Is primarily medium.
Medium Dense
Density Increases with depth
3
Decreasing gravel,
Increasing medium sand
4
5
8 -
E=gwW n terminated at q)proximabely 6
feet
7
8
9
110
No Groundwater Encmuntensd ENVIROTECH ENGINEERING
rwt brbMMWDn pwtsr►a 0*s'MYa borht and aba&nor be Geotechnical Enginwdng
hdwp►asd as bent ixgm of e»w0v Alta.
Start card 013092
File Original and rind Copy with Appil"tion No.
Departin"t of,r=,copy WATER WELL REPORT
Second copy—
Thtrd Copy-Driller's Copy ffAIR (W WASM79OWN Peradt No.
j (I) OWNER: Name.-Continetal Floral Greens_-__......... Add....&Y.3.-NQr01 .9.f-.30f air WA.985Mg.
..
T. 23N..vt....1W w.m.
(2) LOCATION OF WELL. county .... ......
Sawing and disteivem free emetbe or mbdkv%-Mn___
(3) PROPOSED USE: Desmedw a loduatrist 13 "O"Pal 13 (10) WELL 'AG:
jee:J)ewroe co1w cleeperser, an as mentema And scrueem".40011
DTWadm 13 ?*A WeU 0 00— a
Zrw add ean..1 a-
'd lent me an"for am*chmme of foroudba.
owner's umber of W80 ram TO
(4) TV OF WORK: 1,j man nbm eme)- -
Mar won CK lilcumd: 13--
IN Drivel,
jewnrate 0 85
0 becoadMomed Rub"13 JOUM 0
r- (5) DnUCNMNS: mummew 91 wou
m — m]0 mawa.. 222-.-.. _.n. Depm emd _ --
-S-m- od A VMMI with mater_
E (6) coNsTRucTw ,&-x MTAU
CuSiM Fim smd & silts-Vidi mAter- to 190-.—
Threaded from_ ft.
Weld" IL sm4 with water 190 222__
Perferademiim rw a No m
Type of paterahm mood - Silts bdth 1611mm clay 729 2
0 a=at in.by
Clse. ft.
9L to ft.
Sere"m Ties m no a
mmw_Xook
T;q.__staJn1ass ,- uma
ri mmm .___5_ma mite 42-_ Pro-212__&to fL _j=_
Mum -------- SW im- ---trm---ft to fL ir
Gravel pocksk Yes o N.ID stme,ago-v a m I
Gravel pieced Erma
Surface Seel: Twat mou Towbot
material Used in emd_Betcuite_ -------low
Did a03P MMMM eootatn uwtta.bie Mart You(3 M&CL
Type of _aja Daplb of mbuft---
Method Of mosim strata
(7) PUMP:
Type:..--
(9) WATER LEVELS:
static W.W ___118 __ .._.gL boo.*W ce well DM.-
Artellum PrefiNUMM- per momm back
AT1221AD water Is cowtron"by
M WELL TESTS: is npA
N Lowered below ataua level Work amtmL---
C Was a VRDW tsa mesda? Yea 0 NOZ) U Yes.IMY I I
Yield: _gmLAMbL MOM fL-drawdown ever bra. MLL DRELIJUM STATEMOMT6.
Tbim Wdl Well drilled MY jwftdktbm and this man in
trom to the bed of my k=--.. and belief.W
C. Recovery data Man :=IPMW "Usad 0M C EM kvd"red nom w=lo . ...........
Time w4rwr LAMM9 Time wager Lead rilme MOM Level (Perma dram.or corporation) f7mm or prW)
Ral f Ai-r IJA CJR528
Addkoa
............... ........ -V
Date Of zo;j-.. -, .......................
Bmumr bat -AL-492114ftftwatt--
Arlemim r4w__
Temperelum ej waver— We,a Omeal=&agaftak mom Tea[) we CK Licallilill 1600M........ Dale
I USZ ADDITIONAL=XM Er NZCXWARY)
ECY OW 1-20