HomeMy WebLinkAboutGEO2020-00036 Geologically Hazardous Area - GEO General - 7/16/2020 2134692 MASON CO WA
07/1612020 10 19 AM NO10E
DIR COMM DEVELOPMENT #141688 Rec Fee. $103 50 Pages 1
IIIIII!I(Illi III IIII IIIIIII IIII{I IIII IIII IIIII IIIII i�llll III Illq Illll Illi!Ilil IIII
RETURN TO:
Dept. of Community Development
Attn: Marissa Watson, Planner
615 W. Alder St. Shelton,WA. 98584
NOTICE OF DEVELOPMENT WITHIN A GEOLOGICALLY HAZARDOUS AREA
Owner/Grantor: Kyle Quintero
Site Address: 30 NE Skipper Ct; Belfair,Wa 98528
Parcel No: 12330-51-00073
Legal Description: BEARDS COVE DIV 4 LOT:73
Grantee: the Public
This Notice to Title is to inform the property owner and subsequent property owners that_GE02020-
00036 was approved and issued by Mason County following the review of a Geotechnical
Report to determine slope stability within a mapped Geologic Hazard Boundary.The property owner
shall acknowledge the risks inherent in developing in a geologic hazard area and accept the
responsibility of any adverse effects which may occur to the subject property or other properties as a
result of the development.
The property owner agrees to hold Mason County harmless from and against any damage,loss or
liability due to the unpredictable nature of the Geologically H zar=Area
I
;
Dated this�day of ULY 2020.
Owner Signature
I certify that I know or have satisfactory evidence that &LL- (A)UZNTERi3 is the person
who appeared before me, and said person acknowledged that he/she signed this instrument and
acknowledged it to be his/her free and voluntary act for the uses and purposes therein mentioned in
this instrument.
AD I)r
Given under my hand and official seal this 14 day of A 2020.���P
=.`551oN
NOTARY PUBLIC in and f(the State of Washington = 209285 N'
's 4 o 5 Z
residing at V- A '; u',,'% �B�` ZO
My term expires
GEo ?,oZQ ��31P
Mason County Review Checklist
for a Geotechnical Report
Instructions:
This checklist is.intended to assist Stefft in.the review of a Geotechnical Report. The Geotechnical Report is reviewed
for completeness with respect to the Resource Ordinance. If an item is found to be not applicable,the Report should
explain the basis for the conclusion.The Report is also reviewed for clarity and consistency. If the drawings,
discussion, or recommendations are not understandable,they should be clarified. If they do not appear internally
consistent or consistent with the application or observations on site,this needs to be corrected or explained. If
resolution is not achieved with the author, staff should refer the case to the Planning Manager or.Director.
Applicant's Name: _0,01rikVo
Permifi#: �,�1�?�Q��� Parc #: J2��?V51 dd0-73
Date(s)of the Document(s)reviewed: f7l 'J�0
1. (a) A discussion f general geologic ondi ions in the vicinity of the proposed development,
OK? _ �o Comment:
(b) A discussion f specific soil types
OK?_ Comment:
(c).A discussion f ground water conditions
OK? Comment:
(d) A discussion of the upslope geomorphology
OK? �Comment:
(e) A discussion of the location of upland waterbodies and wetlands
OK? ✓ Comment:
(f) A discussionof history of landslide activity in the vicinity, as.available in the referenced maps and records.
OK? Comment:
2. A site plan that identifies the im.portant'development and geologic features.
OK? ✓ Comment:
3. Locations and logs of exploratory holes or probes.
OK? ✓ Comment:.
4, The area of the proposed development,the boundaries of the hazard, and associated buffers and setbacks shall
be delineated (top, both sides, and toe) on a geologic map of the site.
OK? ✓ Comment:
5. A minimum of one cross section at a scale which adequately depicts the subsurface profile, and which
incorporates the details of proposed grade changes.
OK? ✓ Comment:
6. A description and results of slope stability analyses performed for both static and seismic loading conditions.
Analysis should examine worst case failures.Tlie analysis should include the Simplified Bishop's Method of
Circles. The minimum static safety factor-is 1.5, the minimum seismic safety factor is 1.1 and the quasi-static
analysis 'ents should be a value of 0.15.
coe
OK? Comment:
7. (a) Appropriate restrictions on placement of drainage features
OK? 1,!Ll=Comment:
(b) Appropriate restrictions on placement of septic drain fields
OK? Comment:
(c) Appropriate restrictions on placement of compacted fills and footings.
OK? ✓ Comment:
Page 1 of 2 Form Effective June 2008
(d) Recommended buffers from the landslide hazard areas shoreline bluffs and the tops of other slopes.
OK? I Comment:
(e) Recommend d setbacks from the landslide hazard areas shoreline bluffs and the tops of other slopes.
OK?_ Z Comment:
8. Recommendations for the preparation of a detailed clearing and grading plan which specifically identifies
vegetation to be removed, a schedule for vegetation removal and replanting, and the method of vegetation
removal
OK?OK? Comment:
9. Recommendations for the preparation of a detailed temporary erosion control plan which identifies the specific
mitigating measures to be implemented during construction to protect the slope from erosion, landslides and
harmful construction methods.
OK? ✓ Comment:
10. An analysis of both on-site and off-site impacts of the proposed development.
OK? ✓Comment:
11. Specifications of final development conditions such as,vegetative management, drainage, erosion control, and
buffer widths.
OK? ✓ Comment:
12. Recommendations for the preparation of structural mitigation or details,of other proposed mitigation.
OK? %-�Comme'nt:
13. A site map drawn to sGaie showing the property boundaries, scale, north arrow, and the location and nature of
existing and proposed development on the site.
OK? - Comment:
Are the Documents signed and stamped? L°5S By,whom? �l
License#: �i7 _ License type:
FIRST REVIEW Approved ❑ Need more info.
If not approved, what is the next action/recommendation for further action?
� ✓' Gt •, Yo•l� l'Gv
Reviewed by. , on l L) Time spent in review: Zd✓A , n
SECOND REVIEW/ UPDATE ❑ Approved ❑ Need more info.
Reviewed by , on . Time spent in second review:
THIRD REVIEW/UPDATE ❑ Approved ❑ Need more info.
Reviewed by , on .Time spent in third review:
Disclaimer., Mason County does not certify the quality of the work done in this Geotechnical Report:
Page 2 of 2 Form Effective June 2008
�I�o 2Z020- M)SY
2-62-0 - bc"'3 RECEIVED
JUN 16 2020
PLANNING' 615 W. Alder Street
Geotechnical Report
Quintero Single Family Residence
30 NE Skipper Court, Belfair
Parcel No. 12330-51-00073
Mason County, Washington
April 6, 2020
Project#2045
Prepared For:
Kyle Quintero
Prepared By:
Envirotech Engineering
PO Box 984
Belfair, Washington 98528
Phone: 360-275-9374
S
4 -
I
� k 43045 . _�
MASON COUNTY
COMMUNITY SERVICES Geotechnical Report
Instructions:
This checklist must be submitted with a Geotechnical Report and completed,signed,and stamped by the licensed
professional(s)who prepared the Geotechnical Report for review by Mason County pursuant to the Mason County
Resource Ordinance. If an item is found not applicable,the report should explain the basis for the conclusion.
Note: Unless specifically documented, this report does not provide compliance to the International Residential
Code Sections R403.1.7 for foundations on or adjacent to slopes, Section R403.1.8 for expansive soils or section
1808.7.1 of the International Building Code Section for Foundations on or adjacent to slopes.
Applicant/Owner Kyle Quintero Parcel# 12330-51-00073
Site Address 30 NE Skipper Court
(1) (a) A discussion of general geologic conditions in the vicinity of the proposed development,
Located on page(s) 5
(b) A discussion of specific soil types,
Located on page(s) 6
(c) A discussion of ground water conditions,
Located on page(s) 7
(d) A discussion of the upslope geomorphology,
Located on page(s) 3
(e) A discussion of the location of upland waterbodies and wetlands,
Located on page(s) 3
(f) A discussion of history of landslide activity in the vicinity, as available in the referenced maps and
records.
Located on page(s) 8
(2) A site plan which identifies the important development and geologic features.
Located on Map(s) Site Plan—Appendix A
(3) Locations and logs of exploratory holes or probes.
Located on Map(s) Site Plan and Soil Lops(Appendix B)
(4) The area of the proposed development,the boundaries of the hazard,and associated buffers and
setbacks shall be delineated(top,both sides,and toe)on a geologic map of the site.
Located on Map(s) Site Plan
(5) A minimum of one cross section at a scale which adequately depicts the subsurface profile,and
which incorporates the details of proposed grade changes.
Located on Map(s) Soil Profile(Appendix B)
(6) A description and results of slope stability analyses performed for both static and seismic loading
conditions.Analysis should examine worst case failures.The analysis should include the Simplified
Bishop's Method of Circles.The minimum static safety factor is 1.5,the minimum seismic safety
factor is 1.1,and the quasi-static analysis coefficients should be a value of 0.15.
Located on page(s) 9 Page 1 of 37
(7) (a) Appropriate restrictions on placement of drainage features,
Located on page(s) 16
(b) Appropriate restrictions on placement of septic drain fields,
Located on page(s) 17
(c) Appropriate restrictions on placement of compacted fills and footings,
Located on page(s) 14
(d) Recommended buffers from the landslide hazard areas shoreline bluffs and the tops of other slopes.
Located on page(s) 17
(e) Recommended setbacks from the landslide hazard areas shoreline bluffs and the tops of other slopes.
Located on page(s) 15
(8) Recommendations for the preparation of a detailed clearing and grading plan which specifically identifies
vegetation to be removed, a schedule for vegetation removal and replanting,and the method of vegetation
removal.
Located on page(s) 16
(9) Recommendations for the preparation of a detailed temporary erosion control plan which identifies the specific
mitigating measures to be implemented during construction to protect the slope from erosion, landslides and
harmful construction methods.
Located on page(s) 10
(10) An analysis of both on-site and off-site impacts of the proposed development.
Located on page(s) 11
(11) Specifications of final development conditions such as,vegetative management,drainage,erosion control,and
buffer widths.
Located on page(s) 16- 17
(12) Recommendations for the preparation of structural mitigation or details of other proposed mitigation.
Located on page(s) 17
(13) A site map drawn to scale showing the property boundaries,scale,north arrow, and the location and nature
of existing and proposed development on the site.
Located on Map(s) Site Plan
I, Michael Staten,hereby certify under penalty of perjury that I am a civil engineer licensed in the State of Washington
with specialized knowledge of geotechnical/geological engineering or a geologist or engineering geologist licensed in
the State of Washington with special knowledge of the local conditions. I also certify that the Geotechnical
A4 cu by S Report,dated April 6,2020,and entitled Quintero Single
0 i�'j T�r Family Residence, meets all the requirements of the Mason
County Resource Ordinance,Geologically Hazardous Areas
Section, is complete and true,that the assessment
r, k a304 � r demonstrates conclusively that the risks posed by the landslide
��;I�ftF�/`
�:Ssv hazard can be mitigated through the included geotechnical
4�C,�20 design recommendations,and that all hazards are mitigated in
Disclaimer:Mason County does not such a manner as to prevent harm to property and public
certify the quality of the work done in health and safety.
this Geotechnical Report.
Page 2 of 2
TABLE OF CONTENTS
1.0 INTRODUCTION.................................................................................................................................1
1.1 PROJECT INFORMATION.................................................................................................................... 1
1.2 PURPOSE OF INVESTIGATION AND SCOPE OF WORK........................................................................ 1
2.0 SURFACE CONDITIONS....................................................................................................................3
2.1 GENERAL OBSERVATIONS.................................................................................................................. 3
2.2 TOPOGRAPHY..................................................................................................................................... 3
2.2.1 Upslope Geomorphology............................................................................................................ 3
2.3 SURFACE DRAINAGE..........................................................................................................................3
2.3.1 Upslope Water Bodies................................................................................................................ 3
2.4 SLOPE AND EROSION OBSERVATIONS...............................................................................................4
3.0 SUBSURFACE INVESTIGATION.....................................................................................................5
3.1 FIELD METHODS,SAMPLING AND FIELD TESTING...........................................................................5
3.2 GENERAL GEOLOGIC CONDITIONS...................................................................................................5
3.3 SPECIFIC SUBSURFACE CONDITIONS.................................................................................................7
3.3.1 Groundwater............................................................................................................................... 7
4.0 ENGINEERING ANALYSES AND CONCLUSIONS......................................................................8
4.1 SLOPE STABILITY............................................................................................................................... 8
4.1.1 Slope Stability Analysis.............................................................................................................. 9
4.2 EROSION............................................................................................................................................10
4.3 SEISMIC CONSIDERATIONS AND LIQUEFACTION..............................................................................10
4.3.1 Liquefaction..............................................................................................................................11
4.4 LANDSLIDE,EROSION AND SEISMIC HAZARDS CONCLUSIONS........................................................11
4.5 LATERAL EARTH PRESSURES...........................................................................................................11
4.6 ON-SITE AND OFF-SITE IMPACTS.....................................................................................................11
5.1 BUILDING FOUNDATION RECOMMENDATIONS.................................................................................12
5.1.1 Bearing Capacity.......................................................................................................................12
5.1.2 Settlement..................................................................................................................................13
5.1.3 Concrete Slabs-on-Grade..........................................................................................................13
5.2 EARTHWORK CONSTRUCTION RECOMMENDATIONS.......................................................................13
5.2.1 Excavation.................................................................................................................................13
5.2.2 Placement and Compaction of Native Soils and Engineered Fill...........................................14
5.2.3 Retaining Wall Backfdl.............................................................................................................15
5.2.4 Wet Weather Considerations....................................................................................................15
5.2.5 Building Pads............................................................................................................................15
5.3 BUILDING AND FOOTING SETBACKS.................................................................................................15
5.4 SURFACE AND SUBSURFACE DRAINAGE...........................................................................................16
5.5 VEGETATION BUFFER AND CONSIDERATIONS.................................................................................16
5.6 TEMPORARY AND PERMANENT EROSION CONTROL.......................................................................17
5.7 SEPTIC DRAINFIELDS........................................................................................................................17
5.8 STRUCTURAL MITIGATION...............................................................................................................17
6.0 CLOSURE.............................................................................................................................................18
Appendix A-Site Plan
Appendix B-Soil Information
Appendix C-Slope Stability
Appendix D—Erosion Control
Appendix E—Drainage Details
1.0 INTRODUCTION
Envirotech Engineering (Envirotech) has completed a geotechnical investigation for a planned
single family residence located at 30 NE Skipper Court, identified as parcel number l 2330-51-
00073, Mason County, Washington. See the vicinity map on the following page for a general
depiction of the site location.
An initial geotechnical evaluation of the project was conducted by Envirotech on March 25, 2020.
It was determined that slopes in excess of 40% with a vertical relief of at least 10 feet were
present within 300 feet of the planned development. Based on this site characteristic, the
proposed development will require a geotechnical report pursuant to Landslide Hazard Areas of
Mason County Resource Ordinance (MCRO) 17.01.100. During the site visit by Envirotech,
surface and subsurface conditions were assessed. After completion of the field work and
applicable project research, Envirotech prepared this geotechnical report which, at a minimum,
conforms to the applicable MCRO.
As presented herein, this report includes information pertaining to the project in this Introduction
Section; observations of the property and surrounding terrain in the Surface Conditions Section;
field methods and soil descriptions in the Subsurface Investigation Section; supporting
documentation with relation to slope stability, erosion, seismic considerations, and lateral earth
pressures in the Engineering Analyses and Conclusions Section; and, recommendations for
foundation, settlement, earthwork construction, retaining walls, erosion control, drainage, and
vegetation in the Engineering Recommendations Section.
1.1 Project Information
Information pertaining to the planned development of the project was provided by the proponent
of the property. The planned development consists of a 1-story single family residence, and other
ancillary features typical of this type of development. Approximate building footprint and other
proposed features with relation to existing site conditions are illustrated on the Site Map provided
in Appendix A of this report.
1.2 Purpose of Investigation and Scope of Work
The purpose of this geotechnical investigation is to assess geological hazards, and evaluate the
project in order to provide geotechnical recommendations that should be implemented during
development. The investigation included characterizing the general project surface and
subsurface conditions, and evaluating the suitability of the soils to support the planned site
activities.
In order to fulfill the purpose of investigation, the geotechnical program completed for the
proposed improvements of the project include:
• Review project information provided by the project owner and/ or owner's
representative;
• Conduct a site visit to document the site conditions that may influence the construction
and performance of the proposed improvements of the project;
• Define general subsurface conditions of the site by observing subsoils within test pits
Envirotech Engineering Geotechnical Report
PO Box 984 page 1 Parcel 12330-51-00073
Belfair,Washington 98528 Mason County,Washington
Ph. 360-275-9374 April 6,2020
and/ or cut banks, review geological maps for the general area, research published
references concerning slope stability, and review water well reports from existing wells
near the project;
• Collect bulk samples,as applicable,at various depths and locations;
• Perform soils testing to determine selected index and/or engineering properties of the site
soils;
• Complete an engineering analysis supported by the planned site alterations, and the
surface and subsurface conditions that were identified by the field investigation, soil
testing, and applicable project research; and,
• Establish conclusions based on findings, and make recommendations for foundations,
drainage, slope stability, erosion control, earthwork construction requirements, and other
considerations.
N , .
Project
Y
Belfair
r.
u
300
1n u
Vicinity Map from Mason County Website
Envirotech Engineering Geotechnical Report
PO Box 984 page 2 Parcel 12330-51-00073
Belfair,Washington 98528 Mason County,Washington
Ph. 360-275-9374 April 6,2020
2.0 SURFACE CONDITIONS
Information pertaining to the existing surface conditions for the project was gathered on March
25, 2020 by a representative with Envirotech. During the site visit, the type of geotechnical
investigation was assessed, site features were documented that may influence construction, and
site features were examined that may be influenced by construction. This Surface Conditions
Section provides information on general observations, vegetation, topography, drainage and
observed slope/ erosion conditions for the project and surrounding areas that may impact the
project.
2.1 General Observations
Currently, the property has an existing mobile home, onsite septic, and existing driveway.
Vegetation on and near the project consists primarily of secondary growth firs, alders, and other
trees and shrubbery common to this area of the Pacific Northwest. An aerial photo of the project
and immediate vicinity is provided on the following page.
2.2 Topography
The topographic information provided in this section was extrapolated from a public lidar source,
and incorporated observations and field measurements. Where necessary, slope verification
included measuring slope lengths and inclinations with a cloth tape and inclinometer. See the Site
Plan in Appendix A in this report for an illustration of general topography with respect to the
planned development.
Critical descending slopes, with grades exceeding 40% appear to be within 300 feet of the
planned development. The maximum natural critical slope is approximately 43% with a vertical
relief of about 15 feet.The slope has been over-steepened from fill sidecast over the hillside.
Ascending grades are generally located to the north of the planned development.These slopes are
relatively minor within 300 feet of the project, with no apparent slope grades of at least 15%.
2.2.1 Upslope Geomorphology
The upland area of the property and beyond is generally situated on a hillside of glacial
origin.
2.3 Surface Drainage
Runoff originating upslope of the development is mostly diverted away from the property by
accommodating topography. Excessive scour, erosion or other indications of past drainage
problems were not observed within the immediate vicinity of the planned development.
2.3.1 Upslope Water Bodies
There are no apparent water bodies or wetlands located upslope from the planned
development that would significantly influence the project.
Envirotech Engineering Geotechnical Report
PO Box 984 page 3 Parcel 12330-51-00073
Belfair,Washington 98528 Mason County,Washington
Ph. 360-275-9374 April 6,2020
2.4 Slope and Erosion Observations
The slope gradients near the project signal a potential landslide or erosion hazard area. Some
indicators that may suggest past slope movements include:
• Outwash of sediments near the bottom of the slope,
• Fissures, tension cracks, hummocky ground or stepped land masses on the face or top of
the slope, and parallel to the slope,
• Fine, saturated subsurface soils,
• Old landslide debris,
• Significant bowing or leaning trees,or,
• Slope sloughing or calving.
Leaning trees were obseerved on the slope. Other slope instability indicators or 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
w.
ti
t V.-A
Aerial Photo from Mason County Website
Envirotech Engineering Geotechnical Report
PO Box 984 page 4 Parcel 12330-51-00073
Belfair,Washington 98528 Mason County,Washington
Ph. 360-275-9374 April 6,2020
3.0 SUBSURFACE INVESTIGATION
Information on subsurface conditions pertaining to the project was primarily gathered on March
25, 2020 by a representative with Envirotech. Applicable information on field methods, sampling,
field testing, general geologic conditions, specific subsurface conditions, and results from soil
testing are presented in this section of the report. Appendix B of this report includes pertinent
information on subsurface conditions for the project, such as subsoil cross-section(s), test pit
log(s), and applicable water well report(s). Water well reports were utilized to estimate ground
water levels, and if sufficient, were used in identifying subsoil types. Applicable test pit locations
are depicted on the Site Plan provided in the appendix of this report.
3.1 Field Methods,Sampling and Field Testing
Information on subsurface conditions for the project was accomplished by examining soils within
test pits and/ or nearby banks extending to depths of up to 4 feet below the natural ground
surface. Information on subsurface conditions also included reviewing geological maps
representing the general vicinity of the project, and water well reports originating from nearby
properties.
Soil samples were not obtained from this project. Envirotech measured the relative density of the
near-surface in-situ soils by gauging the resistance of hand tools. Within testing locations, field
testing results generally indicated loose to medium dense soils in the upper 48 inches, and very
dense soils from 48 inches to the depth of terminous.
3.2 General Geologic Conditions
In general, soils at the project are composed of materials from glacial advances. The geologic
conditions as presented in the "Geologic Map of Washington," compiled by J. Eric Schuster,
2002 indicates Quaternary sediments, Qg. Quaternary sediments are generally unconsolidated
deposits, and dominantly deposited from glacial drift, including alluvium deposits. This project is
located within the Puget Lowland. Typically, "lower tertiary sedimentary rocks unconformably
overlie the Crescent Formation."as revealed in the Geologic Map. Initial sedimentary rocks were
formed from shales, sandstones and coal deposits from rivers. During the Quaternary period, the
Puget Lowland was covered by numerous ice sheets,with the most recent being the Fraser glacier
with a peak of approximately 14,000 years ago. Upon the glacial retreat, the landscape was
formed by glacial erosion glacial drift deposits.
The "Geologic Map of the Belfair 7.5-minute Quadrangle, Mason, Kitsap and Pierce Counties,
Washington"by Michael Polenz, Katelin Alldritt, Nicholas J. Heheman, Isablle Y. Sarikhan, and
Robert L.Logan,July 2009,provides the following caption(s)for the project area:
Envirotech Engineering Geotechnical Report
PO Box 984 page 5 Parcel 12330-51-00073
Belfair,Washington 98528 Mason County,Washington
Ph. 360-275-9374 April 6,2020
ashon}glacial ice-cool act dcptnih SOW.gravel,lodglitcnt fill.and
ilia till,nunor,th.will:ht beds,tan to gray,variably%orted.Itw,e to
:oulpiwt;rrias,lte 14.ttcll,trluli d,ht ally includes over-sicelviled beds
that typically rvtl,:l sub•+ce flott,but their dip ouiy,along t,lilt
sutall-%:ale%hear%.Am,tune dct eloped a%:ollap%e features ar due to
gl.ua>tcountc aril teotait:deltwuwtton,(omial to the prrun4:c of
inellwatcr alonpwide ice,generally toward the cmd of the glaciauoi,and i%
thus commonly a::ouipanted by stagnant-ice(catures,such as kculc%.tikl
less-txderl)hutninlK kI topography.esker%l,tlur separately nwpprd a,
suhunn(,)gc).and suh})Lictal tx suhaerial oumash:haluich.Ikp,),lt,.uld
morphologic,that,upp oft conceptual a%saK lilt on tt uh Itutil we'Ind
owltm.ater aic:onunon in the ithip area and"ligg:st ilut vdwre liilit Ogle it.
inappcd in tlw pros,nec o(lluted topogwithy,it is conrnoily only a few
feet thick And hKally could hair been niapp4A a%undill'crentiated drill
tuna dgd) I l,cwhcrc.the unit t►uy he oscr fix)it thi:i, i lilt Ogic a(xo
Includes p,atll) :.msolklatcd till%muss"(tnly acctanpanl:d ht underlytr%
angular,And and noted as"%uh-glacially reworked till' by t.apiade(2W3)
tsee(ieologit;Selling).cspr:tally in fluted area,dill I,l:k dead-we
katur:N tiec unu Qgo aiwl i lg J tiudiscussion of uuitluntics lvttt:yn
unit%(,jgic and Ugo t and 11,,ubullits Ql)-Als,(j)lif,otul Qgol) A
discrepancy ht•nttln du%asap end file%aughn quadrangle to tilt,ouill
resulted tahcrc I ogfn full%kabh t aNl"1 imip ped undilCvn'niiatcd
Ouftelnary dqu"lls lumt t lu1 Ktau,:then Lacked field etpx),ures and
getanotpfw,signs of the dead-t:c dcl osa,th:u ate apparent north tit the
btutndart D-ad-i:c topography north at the lxrlind in ilixt rote:d,a sandy
depw.il misplvd A%unit Offos by Logan ind kkahh 92041?)to he.t t,icic,
%viihin unit Qptc.Locally divided into;
Project
/� „rp, � � r� j, 4�✓lJ �t Y
LO
/qr:
l ell r k
0// 1 Aa \ ,cram
rb (l w w >a
00, QV
All Om Din
' 1 ,
uw
09o --
y
ox
�f 1
,
f
d w.r .' 'Y--,r
Geological Map Department of Natural Resources Washington State
Envirotech Engineering Geotechnical Report
PO Box 984 page 6 Parcel 12330-51-00073
Belfair,Washington 98528 Mason County,Washington
Ph. 360-275-9374 April 6,2020
3.3 Specific Subsurface Conditions
The following subsurface conditions are estimated descriptions of the project subgrade utilizing
information from the depth of penetration at all testing, sampling, observed and investigated
locations. Soils for this project were primarily described utilizing the Unified Soil Classification
System(USCS) and the Soil Conservation Service(SCS)descriptions.
The project is currently composed of native soils with indications of fill. Except for the 3 foot
area from the top of slope, the fill was measured to be dense. Proper benching of the fill material
is unknown, and most likely did not occur due to the age of the development. Within test pit
locations, soils within the upper 3 feet of natural ground were generally observed to be moist,
brown silty sand with gravel (SM). The relative densities of the soil within selected test pits are
provided above in Section 3.1. Expanded and specific subsurface descriptions, other than what is
provided in this section,are provided in the soil logs located in Appendix B of this report.
According to the "Soil Survey of Mason County," by the United States Department of
Agriculture, Soil Conservation Service, the site soils are described as Everett Gravelly Sandy
Loam, Eef with 5% - 15% slopes. The soil designations are depicted in the aerial photograph
below, and descriptions are provided in Appendix B of this report.
9
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 directly below the property at the building pad location. Surface seepage
or perched groundwater at shallow depths was not observed on-site, nor indicated on the
well reports.
Envirotech Engineering Geotechnical Report
PO Box 984 page 7 Parcel 12330-51-00073
Belfair,Washington 98528 Mason County,Washington
Ph. 360-275-9374 April 6,2020
4.0 ENGINEERING ANALYSES AND CONCLUSIONS
The following section includes slope stability, erosion, seismic considerations, and impacts to
both on-site and off-site properties.
4.1 Slope Stability
Landslides are natural geologic processes, and structures near slopes possess an inherent risk of
adverse settlement, sliding or structural damage due to these processes. Geotechnical engineering
cannot eliminate these risks for any site with sloping grades because gravity is constantly
inducing strain on the sloping soil mass. Excessive wet weather and/ or earthquakes will
exacerbate these strains. Geotechnical engineering considers excessive wet weather and `design'
earthquakes in order to provide an acceptable factor of safety for developing on or near sloping
terrain with relation to current engineering protocol. These factors of safeties are based on
engineering standards such as defining engineering properties of the soil, topography, water
conditions, seismic acceleration and surcharges. Surface sloughing or other types of surficial
slope movements usually do not affect the deep-seated structural capability of the slope.
However, repeated surficial slope movements, if not repaired, may present a threat to the
structural integrity of the slope. If any slope movement arises, the slope should be inspected by an
engineer. Subsequently, maintenance may be required in order to prevent the possibility of further
surficial or deep seated slope movements that may be damaging to life and property.
According to the Coastal Zone Atlas of Mason County, Washington, the project is within and
near terrain labeled `Stable' and `Intermediate' regarding potential landslide activity.
Descriptions of these mapping units may be found in the aforesaid Atlas. A Stability Map from
the Coastal Zone Atlas for the general area of this project is provided below:
N
Project
Y�.
I
f
11 Ct�Stable
G 9 R,9 Intermediate
O 6 y Modified
O Fal+" ;' My.-UMeea IV Unstable
Unstable(old slide)
Il _._.--- 1 /nu ,<.V Unstable!recent slide',
Map from Washington State Department of Ecology Website
Envirotech Engineering Geotechnical Report
PO Box 984 page 8 Parcel 12330-51-00073
Belfair,Washington 98528 Mason County,Washington
Ph. 360-275-9374 April 6,2020
According to the Resource Map from the Washington State Department of Natural Resources
(DNR), the project is not within terrain labeled `highly unstable' relating to soils. DNR labeled
portions of this project as medium and high slope instability with relation to slopes. A Resource
Map from the DNR Forest Practices Application Review System is provided below:
N ■
i
Project
i
Soils
Hydric Soils
Highly Unstable
Highly Erodible
■ No Data or Gravel Pits '
® Slops Stability-West
11.2 25,o t 00tt Moderate Slope Instability
. High Slope!nstability '
Resource Map from Washington State Department of Natural Resources Website
4.1.1 Slope Stability Analysis
The Simplified Bishop Method, utilizing `STABLE' software, was used to analyze the
static stability of the site slopes. Seismic conditions were estimated utilizing worst case
scenario values from the static analysis, a quasi-static analysis coefficient of at least 0.15,
and applying the applicable values to STABLE software. Various radii's and center
points of the circle were automatically selected, and produced factor of safeties in a
graphical and tabular format. Worst case scenario values were used in the slope stability
analysis in regards to topography, surcharges, water content, internal friction and
cohesion of the site soils. STABLE software has been repeatedly checked with manual
calculations, and consistently proved to be a very conservative program. The following
soil properties were used in the analysis, and are based on observed conditions, known
geology,and/or published parameters:
Upper 3 feet soil depth
Soil unit weight: 100 pcf
Angle of internal friction: 36 degrees
Cohesion: 0 psf
Envirotech Engineering Geotechnical Report
PO Box 984 page 9 Parcel 12330-51-00073
Belfair,Washington 98528 Mason County,Washington
Ph. 360-275-9374 April 6,2020
Based on the slope stability analysis, unacceptable factors of safety could be present on
and near the critical slope,but do not reflect conditions where development is expected to
occur. For this project, at the location of the proposed development, minimum factor of
safeties for static and dynamic conditions were estimated to be at least 1.5 and 1.1,
respectively. See the slope stability information in Appendix C for a depiction of
minimum factors of safety away from the project.
4.2 Erosion
Based on the USCS description of the project soils, the surface soils are considered moderately
erodible. According to the Resource Map from the Washington State DNR, as provided above,
the project is not within terrain labeled `highly erodible.' This project is not within an erosion
hazard area as defined by the MCRO. Erosion hazard areas are those with USDA SCS
designations of River Wash (Ra), Coastal Beaches (Cg), Alderwood Gravelly Sandy Loam on
slopes 15% or greater (Ac and Ad), Cloquallum Silt Loam on slopes 15% or greater (Cd),
Harstine Gravelly Sandy Loam on slopes 15% or greater (Hb), and Kitsap Silt Loam on slopes
15% or greater(Kc).
It is our opinion that minor erosion control recommendations provided in this report is sufficient
for the development of this project, and additional engineered erosion control plans are not
required. Temporary and permanent erosion control measures are required for site development.
Extents of temporary erosion control will mostly depend on the timeliness of construction,
moisture content of the soil, and amount of rainfall during construction. Soil erosion typical to the
existing site conditions and planned disturbance of the project include wind-borne silts during dry
weather, and sediment transport during prolonged wet weather. Sediment transport could be from
stormwater runoff or tracking off-site with construction equipment.
The Temporary and Permanent Erosion Control Section (Section 5.6) of this report consist of
specific erosion controls to be implemented. Additional erosion control information and
specifications may be found in the latest addition of the "Stormwater Management Manual for
Western Washington," prepared by the Washington State Department of Ecology Water Quality
Program.
4.3 Seismic Considerations and Liquefaction
There are no known faults beneath this project. The nearest Class `A' or Class `B' fault to this
property is the Tacoma Fault Zone, which is less than 2 miles to the southeast of this project.This
information is based on the USGS Quaternary Fault and Fold Database for the United States.
Potential landslides due to seismic hazards have been considered, and are addressed in the Slope
Stability Analysis Section provided earlier in this report.
Soils immediately below the expected foundation depth for this project are generally Type D,
corresponding to the International Building Code (IBC) soil profiles. According to the IBC, the
regional seismic zone is 3 for this project. The estimated peak ground acceleration ranges from
0.50g to 0.60g. This estimation is based on the United States Geological Survey(USGS) National
Seismic Hazard project in which there is an estimated 2% probability of exceedance within the
next 50 years.
Envirotech Engineering Geotechnical Report
PO Box 984 page 10 Parcel 12330-51-00073
Belfair,Washington 98528 Mason County,Washington
Ph. 360-275-9374 April 6,2020
4.3.1 Liquefaction
The potential for liquefaction is believed to be low for this project. This is based, in part,
on the subsurface conditions such as soil characteristics and the lack of a permanent
shallow water table. Subgrade characteristics that particularly contribute to problems
caused from liquefaction include submerged, confined, poorly-graded granular soils (i.e.
gravel, sand, silt). Although gravel- and silt-sized soil particles could be problematic,fine
and medium grained sands are typically subjected to these types of seismic hazards. No
significant saturated sand stratifications are anticipated to be within the upper 50 feet of
the subsoil for this project.
4.4 Landslide,Erosion and Seismic Hazards Conclusions
DNR did not indicate historic landslide activity near the project. Mapped slope conditions, as
delineated by the Departments of Ecology and/ or Natural Resources, were considered in our
slope stability assessment. Based on the proximity and severity of mapped delineations with
respect to the proposed development, results of the aforesaid slope stability analysis, observed
surface conditions, and other pertinent information, it is our opinion that the proposed
development may occur in accordance with the recommendations in this geotechnical report.
4.5 Lateral Earth Pressures
Retaining walls may be utilized for this project. The lateral earth pressures exerted through the
backfill of a retaining wall are dependent upon several factors including height of retained soil
behind the wall, type of soil that is retained, degree of backfill compaction, slope of backfill,
surcharges,hydrostatic pressures,earthquake pressures, and the direction and distance that the top
of the wall moves. A structural or geotechnical professional should design retaining walls based
on specific conditions.
Soil parameters for the structural design of retaining walls may be estimated as 134 pounds per
cubic foot (pcf) and 118 pcf for engineered fill and native soils, respectively. The angle of
internal friction may be estimated as 36 degrees and 32 degrees for engineered fill and native
soils, respectively. These soil parameters are based on soil type and placement conforming to the
Earthwork Construction Recommendations Section in this report.
4.6 On-Site and Off-Site Impacts
From a geotechnical position, it is Envirotech's opinion that the subject property and adjacent
properties to the proposed development should not be significantly impacted if all
recommendations in this report are followed. This opinion is based on the expected site
development, existing topography, existing nearby development, land cover, and adhering to the
recommendations presented in this report. Future development or land disturbing activities on
neighboring properties or properties beyond adjacent parcels that are upslope and/or downslope
from the subject property could cause problems to the subject property. For this reason, future
development or land disturbance near the subject property should be evaluated by a geotechnical
engineer.
Envirotech Engineering Geotechnical Report
PO Box 984 page 11 Parcel 12330-51-00073
Belfair,Washington 98528 Mason County,Washington
Ph. 360-275-9374 April 6,2020
5.0 ENGINEERING RECOMMENDATIONS
The following sections present engineering recommendations for the proposed improvements of
the project. These recommendations have been made available based on the planned
improvements as outlined in the Introduction Section of this report; general observations
including drainage and topography as recapitulated in the Surface Conditions Section; soil/
geologic conditions that were identified from the geotechnical investigation that is summarized in
the Subsurface Investigation Section; and, project research, analyses and conclusions as
determined in the Engineering Analysis and Conclusions Section. Recommendations for the
project that is provided herein, includes pertinent information for building foundations, earthwork
construction, building and/ or footing setbacks, drainage, vegetation considerations, and erosion
control.
5.1 Building Foundation Recommendations
Recommendations provided in this section account for the site development of a typical one- or
two-story, single family residential structure. The recommended allowable bearing capacities and
settlements as presented below, consider the probable type of construction as well as the field
investigation results by implementing practical engineering judgment within published
engineering standards. Evaluations include classifying site soils based on observed field
conditions and soil testing for this project. After deriving conservative relative densities, unit
weights and angles of internal friction of the in-situ soils, the Terzhagi ultimate bearing capacity
equation was utilized for determining foundation width and depth. Foundation parameters
provided herein account for typical structural pressures due to the planned type of development.
A structural analysis is beyond the scope of a geotechnical report, and a structural engineer may
be required to design specific foundations and other structural elements based on the soil
investigation. Stepped foundations are acceptable, if warranted for this project. Continuous,
isolated, or stepped foundations shall be horizontally level between the bottom of the foundation
and the top of the bearing strata. The frost penetration depth is not expected to extend beyond 12
inches below the ground surface for this project under normal circumstances and anticipated
design features.
5.1.1 Bearing Capacity
Existing in-situ soils for this project indicates that the structure can be established on
shallow, continuous or isolated footings. Foundations shall be established on relatively
undisturbed native soil that is competent and unyielding. Alternatively, foundations may
be constructed on selective re-compacted native soil or compacted engineered fill as
described in the Earthwork Construction Recommendations Section of this report.
For a bearing capacity requirement of no more than 1500 psf, a minimum continuous
footing width of 15 inches shall be placed at a minimum of 12 inches below the existing
ground surface atop unyielding soils except where setback encroachment is warranted.
Per recommendations provided later in this report, a 20 ft setback from the top of slope is
needed for stability of the home. Foundations located at 8 feet to 14 feet from the top of
slope shall be extended 4.5 feet below the existing ground surface atop unyielding,
undisturbed soils. Foundations located within 14 feet to 20 feet from the top of slope shall
be founded at least 2.5 feet below the existing ground surface. Depth shall be measured
Envirotech Engineering Geotechnical Report
PO Box 984 page 12 Parcel 12330-51-00073
Belfair,Washington 98528 Mason County,Washington
Ph. 360-275-9374 April 6,2020
from the downhill side of the foundation excavation.For a columnar load of no more than
3 tons, a circular or square isolated foundation diameter or width shall be at least 24
inches. Foundation recommendations are made available based on adherence to the
remaining recommendations that are provided in this report. Alterations to the
aforementioned foundation recommendations may be completed upon a site inspection by
a geotechnical engineer after the foundation excavation is completed.
5.1.2 Settlement
Total and differential settlement that a structure will undergo depends primarily on the
subsurface conditions, type of structure, amount and duration of pressure exerted by the
structure, reduction of pore water pressure, and in some instances, the infiltration of free
moisture. Based on the expected native soil conditions, anticipated development, and
construction abides by the recommendations in this report, the assumed foundation
system may undergo a maximum of 1.0 inch total settlement, and a maximum differential
settlement of 0.75 inch.
5.1.3 Concrete Slabs-on-Grade
Interior slabs, if utilized, should be supported on a minimum of 4 inches of compacted
coarse, granular material (Retained on U.S. Sieve #10 or greater) that is placed over
undisturbed, competent native subgrade or engineered fill per the Earthwork
Recommendations Section below.
The recommendations for interior concrete slabs-on-grade as presented herein are only
relevant for the geotechnical application of this project. Although beyond the scope of
this report, concrete slabs should also be designed for structural integrity and
environmental reliability. This includes vapor barriers or moisture control for mitigating
excessive moisture in the building.
5.2 Earthwork Construction Recommendations
Founding material for building foundations shall consist of undisturbed native soils to the
specified foundation depths. Compacted engineered fill, or selective re-compacted native soils
may be used to the extents provided in this Earthwork Construction Recommendations Section.
The following recommendations include excavations, subgrade preparation, type of fill, and
placement of fill for building foundations.
5.2.1 Excavation
Excavation is recommended to remove any excessive organic content or other deleterious
material, if present, beneath foundations and to achieve appropriate foundation depth.
Additional sub-excavation will be required for this project if the soils below the required
foundation depth are loose, saturated, not as described in this report, or otherwise
incompetent due to inappropriate land disturbing, or excessive water trapped within
foundation excavations prior to foundation construction. All soils below the bottom of the
excavation shall be competent, and relatively undisturbed or properly compacted fill. If
these soils are disturbed or deemed incompetent, re-compaction of these soils below the
Envirotech Engineering Geotechnical Report
PO Box 984 page 13 Parcel 12330-51-00073
Belfair,Washington 98528 Mason County,Washington
Ph. 360-275-9374 April 6,2020
anticipated footing depth is necessary. Excavations shall be completely dewatered,
compacted, and suitable before placement of additional native soil, engineered fill or
structural concrete.
5.2.2 Placement and Compaction of Native Soils and Engineered Fill
For engineered fill or disturbed native soils that will be utilized as fill material directly
beneath foundations, observation and/ or geotechnical testing is required prior to
foundation construction. The following placement and compaction requirements are
necessary. For disturbed native soils or engineered fill beneath foundations, limits of
compacted or re-compacted fill shall extend laterally from the bottom edge of the
foundation at a rate of one horizontal foot for each foot of compacted or re-compacted fill
depth beneath the foundation. See the illustration below.
F❑❑TING
COMPACTED
NATIVE S❑ILS
OR ENGINEERED I
FILL
Tlit
UFIDISTIRHED Std-MRA
Both engineered fill and native soils used as compacted fill should be free of roots and
other organics, rocks over 6 inches in size, or any other deleterious matter. Because of
moisture sensitivity, importing and compacting engineered fill may be more economical
than compacting disturbed native soils. Engineered fill shall include having the soils
retained on the No. 4 sieve crushed (angular), and should consist of the following
gradation:
U.S. Standard Sieve %Finer(by weight)
6" 100
3" 60— 100
No.4 20—60
No. 200 0- 8
Table 1
Particle Size Distribution of Engineered Fill
Compaction shall be achieved in compacted lifts not to exceed 6 inches for both native
soils and engineered fill,respectively. Each lift should be uniformly compacted to at least
95% of the modified Proctor maximum dry density (ASTM D 1557) and within 3% of
optimum moisture content. Each lift surface should be adequately maintained during
construction in order to achieve acceptable compaction and inter-lift bonding. Temporary
earth cuts and temporary fill slopes exceeding 4 feet in height should be limited to a slope
of 2:1 (horizontal:vertical). Utility trenches or other confined excavations exceeding 4
feet should conform to OSHA safety regulations. Permanent cut and fill slopes shall be
limited to a slope of 2:1, unless otherwise approved by an engineer.
Envirotech Engineering Geotechnical Report
PO Box 984 page 14 Parcel 12330-51-00073
Belfair,Washington 98528 Mason County,Washington
Ph. 360-275-9374 April 6,2020
5.2.3 Retaining Wall Backfill
Native soils may be used as retaining wall backfill for this project if the total wall height
is 4 feet or less and the recommendations below are followed. Native soils for retaining
walls exceeding 4 feet in height must be approved by the local authority or evaluated by
an engineer. Backfill may consist of engineered fill, as presented in this report, or borrow
material approved by a geotechnical engineer. Compaction of these materials shall be
achieved in compacted lifts of about 12 inches. Each lift should be uniformly compacted
to at least 85%, and no more than 90% of the modified Proctor maximum dry density
(ASTM D 1557). If pavement or building loads are planned to be located within retaining
wall backfill, then 90% compaction is required. In addition, heavy construction
equipment should be at a distance of at least '/2 the wall height. Over-compaction and
limiting heavy construction equipment should be prevented to minimize the risk of excess
lateral earth pressure on the retaining structure. Envirotech recommends that retaining
wall backfill is compacted with light equipment such as a hand-held power tamper. If
clean, coarse gravel soils are utilized as engineered fill, and surcharges will not influence
the retaining wall, compaction may be achieved by reasonably densifying granular soils
with construction equipment.
5.2.4 Wet Weather Considerations
Due to the types of subsurface soils, additional provisions may be required during
prolonged wet weather. Every precaution should be made in order to prevent free
moisture from saturating the soils within excavations. If the bottom of excavations used
for footing placement changes from a moist and dense/hard characteristic as presented in
this report to muck or soft, saturated conditions, then these soils become unsuitable for
foundation bearing material. If this situation occurs, a geotechnical engineer should be
notified, and these soils should be completely removed and replaced with compacted
engineered fill or suitable native material as presented in this section.
5.2.5 Building Pads
Building pads for this project, if utilized, shall be constructed per the fill placement and
compaction recommendations as presented above. Both engineered fill and native soils
may be used for building pads. Building pad slopes shall be no steeper than 2:1 for both
compacted engineered fill and re-compacted native soils used as fill. Building pad fill
shall be "keyed"into the existing subgrade to a depth of at least 2 feet below the existing
ground surface. The term "keyed," as used here, implies that the interface between the
building pad and subgrade is horizontally level. Alternatively, building pads may be
keyed into the subgrade to the above specified depth, and stepped. Stepped fill should be
keyed into the subgrade at a minimum width of 10 feet. All footings shall be located at
least 5 feet away from the top of the engineered fill slope.
5.3 Building and Footing Setbacks
Provided that assumptions relating to construction occur and recommendations are followed as
presented in this report, the factor of safety for slope stability is sufficient for a 20 feet footing
Envirotech Engineering Geotechnical Report
PO Box 984 page 15 Parcel 12330-51-00073
Belfair,Washington 98528 Mason County,Washington
Ph. 360-275-9374 April 6,2020
setback from the face of the nearby descending slopes exceeding 40%. See the figure below and
the Site Plan in Appendix A for an illustration of the setbacks.
STRUCTURE
TOP OF
SLOPE SLOPE
FACE� _
SETBACK I F❑❑TING
The required setback may be reduced by mitigation. See the foundation section provided earlier
in this report for foundation depths in order to reduce the setback.
5.4 Surface and Subsurface Drainage
Positive drainage should be provided in the final design for all planned residential buildings.
Drainage shall include sloping the ground surface, driveways and sidewalks away from the
project structures. All constructed surface and subsurface drains should be adequately maintained
during the life of the structure. If drainage problems occur during or after construction, additional
engineered water mitigation will be required immediately. This may include a combination of
swales,berms, drain pipes, infiltration facilities, or outlet protection in order to divert water away
from the structures to an appropriate protected discharge area. Leakage of water pipes, both
drainage and supply lines, shall be prevented at all times.
If impervious thresholds are exceeded per the prevailing agency code, then engineered
stormwater management plans are required for this project. The drainage engineer must
coordinate with a geotechnical engineer for input with relation to slope stability prior to
submitting drainage plans. If stormwater management plans are not required for this project, then
the following recommendations should be followed.
y
�t`For this project,we recommend that infiltration is avoided in order to maintain slope stability. We
recommend that an above ground outlet is located beyond the toe of the critical slope. An energy
dissipater is required at the outlet. Driveway runoff may be dispersed above ground.
Recommended outlet locations are delineated on the Site Plan in Appendix A, and drainage
details are provided in Appendix E of this report.
5.5 Vegetation Buffer and Considerations
For this project, we believe that a detailed clearing and grading plan is not warranted unless the
prevailing agency thresholds are exceeded, and basic vegetation management practices should be
adhered to.
Vegetation Buffer—Vegetation shall not be removed from the face of the critical slope or within
a distance of 5 feet beyond the top of the slope. However, any tree deemed hazardous to life or
property shall be removed. If tree removal is necessary, then stumps and roots shall remain in
Envirotech Engineering Geotechnical Report
PO Box 984 page 16 Parcel 12330-51-00073
Belfair,Washington 98528 Mason County,Washington
Ph. 360-275-9374 April 6,2020
place, and the underbrush and soil shall remain undisturbed as much as possible. Any disturbed
soil shall be graded and re-compacted in order to restore the terrain similar to preexisting
conditions and drainage patterns. See the Site Plan in Appendix A of this report for a depiction of
the vegetation buffer.
5.6 Temporary and Permanent Erosion Control
Erosion control during construction should include minimizing the removal of vegetation to the
least extent possible. Erosion control measures during construction may include stockpiling
cleared vegetation, silt fencing, intercepting swales, berms, straw bales, plastic cover or other
standard controls. Although other controls may be used, if adequate, silt fencing is presented in
this report as the first choice for temporary erosion control. Any erosion control should be located
down-slope and beyond the limits of construction and clearing of vegetation where surface water
is expected to flow. If the loss of sediments appears to be greater than expected, or erosion
control measures are not functioning as needed, additional measures must be implemented
immediately. See Appendix D for sketches and general notes regarding selected erosion control
measures. The Site Plan in Appendix A depicts the recommended locations for erosion control
facilities to be installed as necessary.
Permanent erosion control is necessary if substantial vegetation has not been established within
disturbed areas upon completion of the project. Temporary erosion control should remain in place
until permanent erosion control has been established. Permanent erosion control may include
promoting the growth of vegetation within the exposed areas by mulching, seeding or an
equivalent measure. Selected recommendations for permanent erosion control are provided in
Appendix D. Additional erosion control measures that should be performed include routine
maintenance and replacement, when necessary, of permanent erosion control, vegetation,
drainage structures and/or features.
5.7 Septic Drainfields
Septic drainfields were considered in our geotechnical evaluation. This includes septic drainfields
with relation to the observed soil conditions, expected vegetation removal, and existing and
proposed topography. Based on the aforesaid parameters, the septic drainfields are not expected
to adversely influence critical slopes. This is also based on compliance with all recommendations
in this report.
,5.8 Structural Mitigation
With respect to landslide alleviation or slope improvements, structural mitigation is necessary for
this project due to encroachment of the 20 foot sloe setback. See the various foundation depths
r � r r
for slope mitigation located Section 5.1.1 of this report.
Envirotech Engineering Geotechnical Report
PO Box 984 page 17 Parcel 12330-51-00073
Belfair,Washington 98528 Mason County,Washington
Ph. 360-275-9374 April 6,2020
6.0 CLOSURE
Based on the project information provided by the owner, the proposed development, and site
conditions as presented in this report, it is Envirotech's opinion that additional geotechnical
studies are not required to further evaluate this project.
Due to the inherent natural variations of the soil stratification and the nature of the geotechnical
subsurface exploration, there is always a possibility that soil conditions encountered during
construction are different than those described in this report. It is not recommended that a
qualified engineer performs a site inspection during earthwork construction unless fill soils will
influence the impending foundation. However, if native, undisturbed subsurface conditions found
on-site are not as presented in this report,then a geotechnical engineer should be consulted.
This report presents geotechnical design guidelines, and is intended only for the owner, or
owners' representative, and location of project described herein.This report should not be used to
dictate construction procedures or relieve the contractor of his responsibility.
Any and all content of this geotechnical report is only valid in conjunction with the compliance of
all recommendations provided in this report. Semantics throughout this report such as `shall,'
`should' and `recommended' imply that the correlating design and/or specifications must be
adhered to in order to potentially protect life and/ or property. Semantics such as `suggested' or
`optional' refer that the associated design or specification may or may not be performed, but is
provided for optimal performance. The recommendations provided in this report are valid for the
proposed development at the issuance date of this report. Changes to the site other than the
expected development, changes to neighboring properties, changes to ordinances or regulatory
codes, or broadening of accepted geotechnical standards may affect the long-term conclusions
and recommendations of this report.
The services described in this report were prepared under the responsible charge of Michael
Staten, a professional engineer with Envirotech. Michael Staten has appropriate education and
experience in the field of geotechnical engineering in order to assess landslide hazards,
earthquake hazards,and general soil mechanics.
Please contact Michael Staten at 360-275-9374 if you have any questions, comments, or require
additional information.
Sincerely,
Envirotech Engineering
Jessica Smith,M.S. Michael Staten,P.E.
Staff Geologist Geotechnical Engineer
Envirotech Engineering Geotechnical Report
PO Box 984 page 18 Parcel 12330-51-00073
Belfair,Washington 98528 Mason County, g Washington
Ph. 360-275-9374 April 6,2020
APPENDIX A
SITE PLAN
SCALE, 1 INCH s 50 FEEI
0 25 50
PROPOSED SINGLE FAMILY
RESIDENCE EXISTING DRIVEWAY
5 FT VEGETATION
REMOVAL BUFFER FROM EXISTING DRAINFIELD
TOP OF CRITICAL SLOPE A
APPR❑XIMATE TOE OF
CRITICAL SLOPE 20 FT C❑NSTRUCTI❑N
EXCEEDING 40% ;'s SETBACK FROM TOP OF
CRITICAL SLOPE
------APPR❑XI'4ATE TOP
SETBACK MAC Ft BE OF CRITICAL LOPE
FNCRnA-H=Il PF ~-23I3 EXCEEDING 407
GEOTECHNICAL REPORT
WITH DEEPER FOUNDATIONS �0
TIGHTLINE ROOF
PROPERTY LINE RUNOFF TO POINT
r 2�� BEYOND SLOPE TOE,
9• / SEE DRAINAGE
DETAILS,
?Ral_C"t QYiR1EP.i LOpATIOIu
EEQCYMV MM3L NRY RE REJBUM FW Rn WE.SE'FE.RAL UrA7.G= :SIWiLE FAMILY RESL11MrE
A&LEP' ML Aim RLFWMTrr&a HAY r_U-"My At UWL-QETi IN IKE GEOT'ECHNTCAL REPEL-
m.lrrf lWMAL ar�oFeT.
2 Mwns.Da VEM NIT r! ]MtiEI!t!'k LII.'k En'_Alm iNIRVE7IIS. 4119-31I]
CJNT'UkS WERE EXTRAPOLATED FR7N A PUa x LIM OURM PC 70 RE 51tWD4 C'
PdUW rW4TFA FIELD MFAylIRFWWS AS EFiPI.AQW1 IN T-F VnTF—>-NIM. I,FGF('AID PNLEI.le=-81-1YIR72
k'-P[AT.
B 3CJNDAKIES VEBE MaT PNUPAMM 7Y A LIII[EFM BURY"%LOCATMNS
OF SITE FFATURES TH%T ARE ROM FERE. SIGH+S 'OP OF SL�Ef,TL'f '{-.yt. T ipsy.. ClpgTppL, iMaV ENAINEERD�
G' B_'�DPM VATER FEM191ETf�ETE„�VI-H RELATMN TO THE PRCMTY ro IN%4
LINES MUST BF YERITICO BY TF.E[INNER F6:CONMFImfilYFS IN THE --a. BL.7PE IF MATOI FELFAtR, YASFMIYiT[MI 4Y'.JAB
GEQIELYML:AL REPORT PAIVIDE%ET3ACUS.BLMRS,'IEPIHS. ETC. VITH DEVA y 9376
RELATMN TO 6EOLOGI6 FEATUMIL V7T PROMPT' LIKM THM GEMMM .�-w—* STRS V4 cm9r fAt
FLATLM MAY BE LMATEC ON THE SUBJECT PROPM'f OR NCGHaCK46 TF-10 TEST PIT STTE PLAN
R rxs.
APPENDIX B
SOIL INFORMATION
VO)Ttt1L NO NORRDUTA.SCAR
DCW-4e c'6T
D w x so
PROP❑SED H❑USE
EXISTING GRADE
9%t
�� 21it
MEDIUM DENSE SILTY SAND
WITH GRAVEL (SM)
SECTION A-A
PROJECT/OWNER/ LOCATIM
SINGLE FAMILY RESIDENCE
GEOTECHNICAL REPORT
OUINTERO
PARCEL 1233D-31-00073
NOTES MASON COUNTY,VASHO CTIN
1)NINM GRADE CHANCES REQUIRED IN ORDER TO ACHIEVE ENLINEER,
POSITIVE DRAINAGE ENVIOXTECH ENGINEERING
2)THE SOIL PROFILE IS ACCURATE POR THE DEPTH Cf BELFAERPO DOx 90�
THE OBSERVED TEST PITS AT THE SPECIFIED LOCATIONS, 360-275 VASNDILTaI 98528
LOVER DEPTHS ARE RASED ON SITE GEOLOGr, 360-273-937�
WELL LOG(S).AND/OR EXPERIENCE IN THE GENERAL AREA
SOIL PROFILE
TEST PIT LOG
TEST PIT NUMBER TP-1
PROJECT: Quintero Geotechnical Report DATE OF LOG: 3125/2020
PROJECT NO: 2045 LOGGED BY: RJM
CLIENT: Kyle Quintero EXCAVATOR: N/A
LOCATION: 30 NE Skipper Court DRILL RIG: None
Mason County. Washington ELEVATION: NA
INITIAL DEPTH OF WATER: N;A FINAL DEPTH OF WATER: N A
SOIL STRATA, STANDARD PENETRA?ION TEST
DEPTH SAMPLERS USCS DESCRIPTION LL PI CURVE
AND TEST DATA DEPTH N 10 30 50
0
SM Medium brown,moist.medium dense
SILTY SAND with GRAVEL Gravel is
primarily well-graded and subrounded
Sand Is mostly medium No plasticity
2
3
Excavation terminated at approximately 3
feet
4
5
r,
7
8
4
10
No Groundwater Encountered ENVIROTECH ENGINEERING
This inlormatron pertains onry to rh-s Doting and shOLO rat be Geotec hnical Engineering
interpreted as being meficfive or the entire site
Map Unit Description Everett gravelly loamy sand.5 to 15 percent slopes---Mason County.
Washington
Mason County, Washington
Ee—Everett gravelly loamy sand, 5 to 15 percent slopes
Map Unit Setting
National reap unit symbol 2hk7
Elevation 50 to 500 feet
PAean annual precipitation 55 to 90 inches
P4ean annual air temperature 48 to 50 degrees F
Frost-free period 160 to 180 days
Farmland classification Farmland of statewide importance
Map Unit Composition
Everett and similar soils. 100 percent
Estimates are based on observations,descriptions,and tansects of
the mapunit.
Description of Everett
Setting
Landfeam: Terraces
Parent material Glacial outwash
Typical profile
H 1-0 to 7 inches. gravelly ashy loamy sand
H2-7 to 21 inches: extremely gravelly sand
H3-21 to 60 inches. very gravelly sand
Properties and qualities
Slope 5 to 15 percent
Depth to restnctive feature More than 80 inches
Natural drainage class. Somewhat excessively drained
Capacity of the most hiiiiting layer to transmit water(Ksat) High to
very high(5 95 to 19,98 in/hr)
Depth to water table More than 80 inches
Frequency of flooding. None
Frequency of pondnrg: None
Available water storage in profile Very low(about 2.5 inches)
Interpretive groups
Land capability classification(irrigated): None specified
Land capability classification(nonrrngatecl) 4s
Hydrologic.`moil Group A
Forage suitability group Droughty Sods(G002XN402WA)
Hydric soil rating. No
Data Source Information
Sod Survey Area. Masai County,Washington
Survey Area Data Version 15,Sep 16,2019
.t,i Natural Resources Web Soil Survey 4/512020
r Conservation Service National Cooperative Soil Survey Page I of 1
File Original WO First Copy w Nonce of Intent VMW
Depamnentof Ecology WATER WELL REPORT UNIQUE WELL LD.t _A 1�4
Sated CopyOwrer■Copy 1(77"� STATE OF WASHINGTON
There Copy onlleh copy Water Right Permit No. N/A
(1)OWNER: Name SHANNQ16, M-10NY HUBERT _ , Address 240 MISSION CREEK RD,BELFAIR.WA 98626
(2)LOCATION OF WELL: County MASON NW,yf4 -AE_ tf/SK 30 t 23 N R M Will.
(2a)STREET ADDRESS OF WELL-ne.."addresal .__..��LfrSNt�
--- 114 MANOR RD
Q TAX PARCEL NO. 222133090071
ix (3)PROPOSED USE: IE Domesuc Industrial 'MOk" 110)WELL LOG_or DECOMMISSIONING PROCEDURE DESCRIPTM
tfgatlon Test Well OOlaf Dr color.Ghrsasr,saedntaMel aaa sawara.aMMe suit aria
DeWaw rlree of ae essential ar such stakes parrsteYa.wo all Iasi are uey air sun p
altbeYat IrseYYraaWarephrarae.
(4)TYPE OF WORK: Owners number of well elf more tnanane)
X New Well Manned ---- -. _.
to Deepened i_1Dug (�Bmad WN SAND ._. _ __.__..—.-- ._,.0
Recandmorled []Cebe ( iDrmn OWN SANG AND CLAY 37
De sonar ($IRpary LJefts; BROWN CLAY AND SAID 37
0 (S►DIMENSIONS: Diameterorwad _SIX N4hN BROWN SAND AND CLAY
C DnRed 160 feat Depth ofcomplewWAN 141 _R. BROWN SAND WIB _
0 BROWN CLAY AND SAbQ
is (6)CONSTRUCTION DETAILS:
R Casing Installed:
X Welded �_ 'Dom MCIn ♦1j IL 10
R —'
Plans,"a '%11- R
u.oswtx.- "ERtert.*oe 1RM R
4: Tpp2 of Fue7al mow. _
GwitifalRI IV _ _!_.ie_IV >L
/d�M11O,
/NAIIMW"s.. 1L>r i
' laue.halt i1a i
sewenrr V4.r,% WttaPaeEoeNlle_131 _ ---___--
M.rwacharers Name JOHNSON
RType STa9±LESS_STEEL
0 Diem. 6 Skit size 16 from 131 Lb 1K 1L
Olam S Sal eat BLNKfrom US a as 141 R
ammmimp~ M oft 1N 0 S1Milp
O1MINt1ushown
M1Aodulfgdoe
aswww,arwwA�',� � 11nMifiNIM. ,,,,tIL S7N�/IYMl� ,.1st
s1.lerstMl �,� a esa�taroe vas 4 *a Z ca"TMOM aGwArlm
Mc alcN gIr ISM1N 3a w arAL.nN ii aft Dole,
� I constructed ensiles accept responLD,uly,for ronatruclmn d this wan.and its
` Artesian wow a convened by LMnpWn[a wen on WashingtOA well CAntINc1ion standards Mererials used
I� ICaD.valve.M[I are Ise information rep
orted ported spore are true to my past knowledge and Delel
0 (9)WELL TESTS'Drawdown is amount water ievet is lowered Mbw soap betel Type or Prm1 Name NICHOLAa-r6_ERN.BT. License No 2147
U Was a pump teal made? _f Yet!X,No ayes by whom? IL� �N 0 1,
yield gal"in with n drawdown after nrs W enaa Yield gal/m rt with n drawdown aMr �. Trainee Name Lie No
4— �_---...—.
Y.ad gal Aran.with It drawdown user his Onung Comp0.C%O
--
Recovery data time been at zero when pump turned off)(water level measured _.--
nbrn well top to ware.level, (Sig
s gnedl 2147
C Txne Water Levaf Time Water Level Time Water Level
C` _ __. - __-_ _ _- Address PO BOX 2227 BELFAIR WA._4952t_ —_
R _—. — — _ _ -- — Contractors
0 R"'strauon No TOPDODCO54RA Dale,1f1SCt004 ro
— -- ---
Banter test 10 gal tints with 10 R.rUttardowt star 1 his (USE ADDITIONAL SHEETS IF NECESSARY)
QI Aatett gal shin with stem set as it for nrs
Artesnan now,
Ecology is an Equal Opportunity and Affrrmstrm Actin employer For
).._ --- g p m Dae 3/11/2004 special accommodation needs.contact the Water Resources Program a1
TemperaNfe of water Was a chem"I analyses made?t_;Yp..X NO (360)407.6600. The TDD number is(360)407-6006
APPENDIX C
SLOPE STABILITY
1 . O O
1 10
1 . =0
1 . 30
40
1 . 5
1 . 60
r 1 . 70
1 . 80
190
. 00
Fr _ j«=._t. Quintmro Repert
=Lf I Dynamic Analysis
Analysis alzhop
0 0 0 0 0 0 0 0 0 0
0 H N m 7Lf) to r ro 0) 0
o
'J I
u h
N•rI
M V N
s
♦ o �
d � lgE
♦ II
u r1•�I
d' 44
•n
u u 4
i N �dG;
APPENDIX D
EROSION CONTROL
GEOTEXTILE FABRIC
WRAP AROUND TRENCH
TO AT LEAST ENTIRE
BOTTOM OF TRENCH
BEFORE PLACING GRAVEL 2'x2'x5' WOOD POST OR
12' DEEP, 8' WIDE TRENCH EQUIVALENT OR BETTER
FILLED WITH 3/4' TO 1 1/2'
WASHED GRAVEL OR VEGETAT N
es ri
DIRECTIOX OF EXISTING
WATER FLOW or GROUND SURFACE
Ira R
SILT FENCE - CROSS SECTION
N.T.S.
2'x2' WOOD POST (TYP) GEOTEXTILE FABRIC
OR EQUIVALENT OR BETTER AND WIRE MESH
@ 6 FT MAX. O.C. -�
e.
EXVTINU rl
EiROJND SiRFACE
K!Me T
12' DEEP, W VIDE
TRENCH FILLED VrTH 1rr
3/4' M 1 1/2' a FT
WASHED GRAVEL OR VEG L
BOTTOM EXTENTS OF
GEOTEXTILE FABRIC SILT FENCE - DETAIL
N.T.S.
PROVIDE FULL WIDTH
3/4 IN TO 1 1/ I`bo FT INGRESS/EGRESS
CRUSHED GRAVEL
PLACED AT 6 IN
MINIMUM DEPTH
WELL-DRAINED
SOILS
-0.02 IN/MIN FULL LENM
R=25 FT MIN
4 —
ArrrtS ROAD
STABILIZED CONSTRUCTION ENTRANCE
N.T.S.
UZWONd 3 L JO SMO 9NIW310 3HL wOdJ 3dOISNAM a31vMl 38 TMMS S33N3J IMS'
33MJJ 1VS 3H1 wObJ 3d0'lsdn QNV Si
311 JO 3NI1 3H1 MUN 1331S SINL Nil S'IIY131 3LL ILL 9NIOM33V a31YAVOX3 38 TWHS HON381 V'
'03Sn St 9NLOWS 1SOd MOM ONY 'c1N3WVlLA3NOW) 31b1VJ bMIU HLON3b1S-vdlX
JI 02LVWWIM 38 AVM NS34 3MA 3111 'LUTALn03 d0 39nvD ►TX.2X.2 38 11V11S HS3W 3bam '
RWMW 3Hl W0 A-Mnj3S YIUMt
OW'133 6 WHI NO 9VV130'31L NS a3LYMK SNid33 LV 333Y1d QNY 03:':VdS 38 I-WS :LM.
•1NY3Vd
NI 1•0 MSE'N1a SM SWA 3IL M S3'WWIS.I"MIT 83W31SVJ 38 lIV 49 '1POVJ 1GLLlIA DbYONYl9
'iSOd 311❑1 SON3 HID
lY 03RUSv.A AT3Yn;M3S MNV dVI--;kko H3Nt-8 WnQ11Ti5 V Hilt-, IUW Ahoadns V IV AIND 3t3Alaw
a3=1&31 IlVHS 3UlVJ 93L-U'AVVSS333X+32W SlKMr A UMW M 35n 0MAV Dl 40IMN H
A NI%M ail Ol 1nO TOi!SnwNtlNw Y M 33S1�1d 21 Tme Tl"u bl VU V IIL UM'
SGNYONYIS Alwm TW3 AW NO .fdS" MM AMU 3HL
'WWM L13139VWMd b3LVAMUMS.ail NI 33.1MA NEW 32 TMl!3dA1 XaavJ aLTA 31[1Y31It39
23NU I'D
'33N3J 111S V►►JnadHi M AlEIUVJ NOliN3138 1N3WMM V M NIVba INNS MRVA
HSVA QNv AM0l 03HSnd3 H11A 03d3A03 V3bV NV NO 3NOa 31 IIVHS 9NMVA MHl '133b1S a3AVd V Sa31N3 3131H3A 3M1
3MJ39 JJO 03SIlH 36 TWHS ST33HA 3H1 'S133HA 31JD43A 3H1 wObJ Unw 3H1 3Ap13M ATJ1vn03Qv LIMN S303 QYd Mi A'►
'aVd 3H1 JO N0113NnJ d3dabd NIYINIVN 01 ATIVOIQOld3d a300V 38 TNHS 9306 1YNM.LlUaY•e
'S31IS lVI3b3HWD3 TWWS QNv MINXOSM AVWVJ-319NIS WJ
a3AD040V 31 AVM MW b311YWS. •V30Y=3093 QNV SS349Ni 313Ik31\3W1 JO KLMA TTU 31 TIMIS HLMA VMS 039NA SI9
M 387M I NOU MM HIIA IM19'AU 133.1 HIPS 9NOl LTM M at* =Ml&V=M IMM 1Y 39 TMO No:AJOb 3H1 'P
M"NQLl13S eNOIlb"JJJT 31K 4WJWlt.MV11.5 9="M i EL FM T HLIA M%38U-4101
38 4 Wa'INM GSM ntlifltl.3 31DWS -MICAM30''AJ HJK l of V1 STW O AANYM KM 9 M H"JHI*36 Ti'!NS IVIIl91VN')
3'YNY IN3 HMI-t 41MW 0IMURVIL
W"931G*#A 3 L OL Els81a' ,v f3Wig1*4 V llaH::73' %,M!L Ol 4 7LL sn 430*0 431s1 WIk M.'tADV3iM't
"DWIGM 60 JMQOIOS 93SOdO6e eA'*.Vfv49 e3dONd OL'kLktbdM%3N 3SIAb3HLU AVM 1V111 191X3 SNML 4NM
N3M W'L3A AMAISSMX3 ST 30VbJ9'lS 3H1 QHl 'M.LIQ%03 AQ9nw tO N32MbJ V NI 3'W4A a33Vld 31 LGN TP"'=S Gj'E
931N3A3dd 31 1SnN S311d)KWS Wtl1 ON04OV31 1N3NIQ3S'NMV3S AM NI'2
'TE
N3dVW 9M T 83MAW N33ALM A Qva(33LAM 03AGddd d3H10 M DNIMA03 31LSVld NUA>03ZIIWVIS 3N T M15 313
d)MS It
1N3 PY"W 3'ld43a1S
'a3MURvls M 43133LObd A13LVIedOde
N338 SVH V3dV 3NVI 03NOlLN3W3MJV Sv 3141 v N3ns 1Uhn 3SV30 A MLVM3wN
T?MS 'A11AI13V 11181NO3 1N3WIQ3S QNV NMSOd3(13AObddv LOJ 1d33X3'3IS
NO A13AI13Y NOI13nb1SNO3 TN''a3bV313 N338 9NIAVH b3LW SAVa 9 a3ZI38v1
A131Y1bdOdddw N331 ION SYH M a:L33LBbdNn sMv►pb 03)18W Al3A1L3 19N
ION V3dV ONVI ANT 1"U 1N3A3 ail NI'S3Al3SW3NL JO(INV NI b3AC 31vn03Q
SV 03AMA 36 SON lum ":L3'SOMd 1113)D.03S 'sdv?a lkadnx 'nNLIN31 I L
3WW11 3 hJ 9 M TMM 1.718'L2=MID=JJ012N1 30AYJLL02 � Al3AiJ.3li mm 11A JI 23RM111IJ0 MD owdo I'[33R
T1V'l!Q'y?1iNl'CAl1Y1W 3lLL NO T1QIa)i3OO AUMA LMM HME 112LA IIAYR�R yM UM"U31'.WTAMVN 1lOIQHIn'p��11LQn=UM
No
WA'MOM W K6M 7187A''n H=XX M HIKU V MVJM 3A2I;1xUAidd T3A2�331 xv�13Y118 Me'M.L�Ul�.13Vtr"I
=A'nU''*W3:LY1Q'3 d 3N1 Dl SM MOM 30 TMM SEd=X V
ow AIRS 149M AVM AD"'AM 1VR Yt3113LM20>it 3112-i{I
Mwal :BN af, '.ai 0'7)ANtl01 aw"M-1 3.1 l>A 4u.R 22L1M30 LN;.IFG33S OON4=063 M AM 03L3a3NM IO N d=1l w)f 1cC81!3
381 lw l A
'bM_.'l=3LII)- Mme)MEUS-vt 2 11t>&""I N7Hlth A3xIVMY19 NO am=38:IN."V �yy'1 Hmi ;TMIEL
?wz a60 mogi im 93Am No G3,35 u 3Q alildi? lflT4d101.8 nLM 311 11*1 li3AM G)d10M il3)110 11W NOUV13O3f+Rf.1al. AO VAMG
BIfiS s13Yle1rJ 3H1 �NIlMld"I AO:Mt(*3-0 3H1°J20Md N'L SI ILRALUW IYOtig;1',LS,
d."1-P,3N OL.3 L'T3I'W.�rtlil 1lOJ C35f1 V(71:91H."aCY`.c�l. 101." 3IW.3WKA IMn NO -M'TRW TWI I L"RWIM,!QIWM 1
:'"OS�-M •S3IlIlC"crYJ -[%LA I lX3KM3M NW H07=3 TIY JO MWa3b 9W 3MaP AWN
A33 3 W M1fAM 31 11YKA ML'VAL1m'd A-rW AO 3HL VM A*3t,3 31M0 1
I V39JUMUii A8 0392 o3 39 TAd NO-VW?N2'If13 IV7IIM 1V Orw'Sl'h3«3 VW14 ll31JV 1131V013MOU SmLrIL.Wd 1Q0118:11?13RW3id3
s
TW WXV3M 3LL JO 3211 MA M�M 3t iMOJC N:NP,SlnW NaMM3 llV M HUL7-%-t&M 3NL Wi 10I3i0d=X TMit MITI
K NO 2N OMM V3L.JY ATUViT W EMI 39 TYdM S)N1RYM V 3Hi'Sj--[ 3+a min4 ! v 1.AY31 lY MA mg it
rMP3I AWIVANIMM 02 RNll.MV3W lM3kO'M%M 31I3 min b a 93LUALN IMII1�1LSNO3 1VHL3HL
Mffr MSOdX3 W1IA SV3W-17V M 23rWY 3t 0`rM WOMW'2
383V did SaNnOd W31d3
OOOT JO 31Vd V Iv a3tlddv 38 OTaHS QNV '3SLTLnIM:)b38IJ NYHL d3LYl ON AB Q3llvLSNI 38 1Snw"313 'S13mvil NMSOb3 '9NI1Sv0WA 38 Ol a3aN3WWO33b 38V 9NIN31nw sm 03Sn SlVlb3lvw I'9N7113N '9ND0710+ SY N3nS IGAM aNrMo M QMU31 3AI1vNdMl8ISSION St NM.LvZIlI1v1S 1N3NvMd 1VHL 1N3A3 3HL NI WIAMM AiVS9NIH3lnW 3AM(IN03 3bv SNMilaNO3 ITIN3WOWAN3 3LL QNV LN3004 SI L3H1N0113IdNp3 IVOISAHd N31A 31AU 38 IIIA T MCU30 a31dv 9NIUUM
(SN3d3b Wnr KUldl) ILL ST lsn9nY QNY 'sT AVM M T MJbYW(SMIb3d 91QAG'rMJ 3HL 9Nldna U3HMJb
06 96 Ot a3A013 H31na 31I4A 36 IWHS SV38v UVIRLSIO 3SIA83H10 M U3bV3"13 JO 9NIH3lnw UNY 9NIZClIId
(13)134 'MMVHS 'd3NNV8 'Nt%MS3NVr) '9NIQ33S 'A1Nn03 3H1 A8 03ADbddv 3SIAb3Ull SS3lNn NOLL3V J0 NV
(vlvinwwaD Ybenb V3n1S3J) a3A0bddV 3HI bad b3NO0S bO of b3QHM1 OS A8 "313 'IV12131VW DNINIVbQ 33b
08 L6 01, 31S3J 9NIA3H3 'S13XNV18 NOISOM3'9NI1331S 3ILSYld "All 3N '9NI1{3lnw JO 3Sn 3H1 H9n0b
06 86 D► (wnaaimrnw wonoj) 3Ab ivnNNY 03MISVIS AMIVIb.ObddV 38 iSnW 038bn1SID 3SIA23H10 b0 03MY3M S
06 M O; (Y8'N SELSOaW d6103d I-W 'Nvld'1>Id1NOD 1V3NI03S &W NMSO83 341 NI U3EA13ds SI NMVZIIIIV
3LVIQ3HWI SS3111'8V3A N3AM V M OE dMW3ld3S NVH1 U31YI 13N A
ou cX) (%)lbM3A A8 3NvN 036SUSI0 3SIAb31410 b0 Q3MUM N333 94IAVH d31JY'33ZrlMviS 3SLs8
YN1ww9 Allan SHOIADJEWd 31 M d3AM 3A11331i1dd 31VIN"ddV 3AI3338 NV3 Sv ONVI H:)rA SV A
Dl a31IWLl 38 ASTW'b3AWJ GWlOWJ 23H1D dO NMLV'1313A 9NILSIX3.! 1YA
'WIXIN 833S 31VNb31-N 33AObddV A1N M Y NO '1081NM 3HL 9Mn-UNI Awl JO w8v3l3 3FU -- (CC d38w31d3S na{1 ; AYN)hO5Y3S A
MOMW MU 3MILL'NW M335 G3OO/�Qt 91QAOT11d 3HL 3Q1
'ISO WU3A IW 53MOR WIVA M IN 374M 04A.L 7'�pTW NILP a311(3WO1:V 31 M-W L" iM-WLL UWO3rd3%13 3
ATNE33M=CWM 36 RTM 3LIAVW 33>IRI.VOf3iMQJ'*I AO 1 MMIS 39L M U JJ 813R3M3L'.A33=U AMM OMW33 I&SKKIN W381nl1
.171371dm ILL SN)MCr=1311 31 M 3W 3M3ZrKLV 3 19 H91107M1L IPW JO 3 WOO 311 tPWM 3�l 1MI LA3a,'NI'34 A-M TIM 30.0
-4"•AW=3=3L TM=CM 3L1 A i Vft ��o�1IWk 2VVW 411AKfY88 NITJ1 Lf>�.CtT"Ir k-Eh `LI
W TJIill S W If L1 ROM M OU39 10lWfk�SM V 3M 1SOM MAMY 93VCt1W TV*AO-M 11MLW MU3"1 341 4"(33MU SM''
"MUZA ti JMK!LL L:OLLOl d ON glum V M31YdI7a1"a �AUKUN A ON 310M 4W'8311AI13Ni 1
M ANB�i SY 221ANX M{YM aVUG MW MC[M7AM M 32 RNA"T�M MIUM99/s JO Q3aiQU MM 3ANH 1(30^@4T3fi IlY
TM W MMUM L6M!T AM M321U13S MMMIIE WN EM IV
-jow NU 221111M 0i JD AW 311L 1V 33a-kkM WLIM TOa=M7I Mkt '
39 G"M m"a'Aa'm MIMC W VxV3 ag71 LN�RI'3ii Y
114";FL LLL�NO Y381'?1YWa A�4M 3AY17 SWJW Until all lllhTl 3.
gxmwm IYd3M 1-W M8MJL131�ZWAMti 83IIAOTOJ MI AJ3l 31 TMN2=a(m IINN'Y3LL1mvi'1DY1)=Lm7lkmm MN(Atsm -rw
'XNAM'IX 31U Al?WJ HLIA WMA 39 '1'MO 9M MOR MU Sb '12YSA�731 Jl'a3NIIV O N A-MVXMQ CAW Jim 03LL 'I
WSW 1l13KMA OhV%K JV311G liA9l 137 A3 A TWM=xA30 mJv SWJTII7YJ I L.IMY1 MOM Sw NID201MG 11w'
"=93 4M.3MIM '1L33M01 LNMMU Md HZV SMWM '8$1TCIMJ-DNIL1 i 1M3AW3S"V t6m"u-r*uuxm T7111dD TMi
MVLNIT J"IM rW.OM M-43:4 T7*IM TbMW 3 UM 4 ?AL"WIM"3l1%UVYNI'M''^'t}Y!l 31Hf"M"ll M OL.I ANd 1N-W
1b Pk:OH:1 E?/S1f31"R.'(lh'ff3 14t3+Qi133 IPC:Y b[IIS;m3 Ath4,X.W31 3H1 tll!OH^'
[c3dD'LS 'N�m1'aS�S
+4`3100 lolllfMpc M]<Man lH(Tdl1;i'Ji1
APPENDIX D
DRAINAGE DETAILS
HOUSE
DRAIN, SEE
RMF DOWNSPOUT
CONNECTMN
DETAIL SOLID
LID GROUND
SURFACE
2%MIN
2Y,MIN
4' DIA.MI
SOLID PVC FINE MESH
SCREEN 6' SOLID PIPE
PE
CATCH BASIN ANC�R
<YARD DRAIN) rANCHOED PIPE
PER TIGHTLI
DETAILS J
ROOF DRAINAGE DETAILS 4�f
N.T.S. �SJ,°q'VCy
J�
STEEL CLAMPS (TYP)
CORRUGATED TIGHTLINE 10 rT MIN SPACING 112 INCH DIAMETER
6-INCH MIN, DIAMETER SECURELY FASTENED TO PIPE
LEVEL SECTION
3FT DIFFUSER TEE
TWO4 S OOT ANC r I
ANCHORS (TYP), `III`` NOTE4
N4 REBAR OR 1. IT IS STRONGLY SUGGESTED TO
EQUIVALENT 3 R MIN UTILIZE A HEAT WELDED HIGH DENSITY
pOLYE7HYLE%E(MOPE)PIPE IN LEU EF
en7ALIGA'IEL RLAcnt Pm
C v PLASII=?O't 13 Gts x maw,
VUMCTMK 131-AWAALY),AND
-mlm ar n>rrAn i A� IfA1VIE.w"DZ 1 ,
3 HOLE ITIM TEA SHALL LE 1 B CH FOP
N.T.I. 6-PL-H TEES,AND 2 INCHES FUR IL-IMCH
TEES.
4.HOLE SPACING SHALL BE EQUAL TO
(L5 x MOLE DIAMETER).
5. DIAMETER OF TEE SHALL EQUAL
DIAMETER OF TIGHTLINE PIPE.
NO HOLES OPPOSITE
PIPE
0
0 o°° DRILL HOLES
o o°° IN FRONT HALF
°o ° IS TEE ONLY
\ 3 rT
ENERGY DT SIPATI�TAII'Z
NJ.&