619 ELM PL.PDFIiiiiiiiii lill
11150
619 ELM PL
40
ADDRESS: 619 ELM PLACE
TAX ACCOUNT/PARCEL #: 00736400003000
BUILDING PERMIT (NEW STRUCTURE) #: BLD19870205
COVENANTS(RECORDED)FOR:
CRITICAL AREAS #: CRA20020022 DETERMINATION: Ej Conditional Waiver El Study Required Z Waiver
CRITICAL AREAS #: DETERMINATION: - 0 Conditional Waiver F1 Study Required F1 Waiver
DISCRETIONARY PERMIT #'S: PRD 1983-1, ADB 1983-88,
DRAINAGE PLAN DATED:
PARKING AGREEMENTS DATED:
EASEMENT(S) RECORD FOR:
PERMITS (OTHER - list permit #'s): BLD20020184, ENG20020076
PLANNING DATA CHECKLIST DATED: March 20, 2002
SCALED PLOT PLAN DATED: March 12, 2002.
SEWER LID FEE $:
LID #: ESR 279
SHORT PLAT FILE: P 1983-9
LOT: LOT 30
BLOCK: ELM PLACE BLK 000 D-00
SIDE SEWER AS BUILT DATED: July 2,1987
SIDE SEWER PERMIT(S) #: 07674
GEOTECH REPORT DATED: September, 1986
STREET USE/ENCROACHMENT PERMIT #:
FOR:
WATER METER TAP CARD DATED: NONE IN FILE AS OF September 10, 2008
OTHER:
7,
;:,7
U-
eJ
70
IT, Y* 0 F E D M 0 i�s RS�6/PRD
UCTION PERMIT APPLICATION
C NSTR
IA.t f1v 01 6VS IF�N, (jig F11r.
Homeland Homes Inc.
5 11, James 11,
ot I I I
Ednonds 1`17�. 20 3 fi-, 114 E.
J
Design Consultants 1,�I, CI ',�IA 1, --.1 F--- -.11.
toj-�
609 10th.
A Mukilteo 745-1,569
OA/
Homeland Homes Inc.
221 James St.
CITY
I TELL
Edmonds
7 5 2
SIAIE LICEN'�E .-UMBEA I,I.BEF f
n/a IW. A, 11 -U-- I
0-ME-LHI174 KE tic ...........
Legai L�ascription of hPropeoy -nicittde easenre,nts
shotiv 1) 5)
edworattac ourcuples
I �-i
1A.—I all C. f;."
10' 10V111C1
Z�y
114
njtL OF tva;-r, 70 BE -NE 1�11ACII PL-T P-1,
construct single fan
Lot #30: Plat of Elm Place.
y
N1.
Ku-BI.-
AMALIE NQN.AESIOFNTI�-L
Ej -VIC-NICIL
Ir-A:Illr-
0 1.,1,
11CAVITIF
[IiE..Us. 0. FILL
'FINC1.
Z�
SIDE SEWEII "ATER LINE
I .,U.E1Fi Cl IT.M11
we
Ll",�LLINU
7
ily hone --7-
P.1t
14
k.,, Ya:� 1,
TM.s W-5 vork :O.De done 0�. P:
An, Cw5I,LCI;oh 0.1 'he
B",ays. marquees, etc ) tvil! I
7;,MrIApp;,CjI,d,t-180Days
180 D.�s
Pe,rh I Li-t I YeB, - Proy,�ed Work is S
a'd
"A or. bei-31 T1 his Q, he, 5pous�. 0,
suctesscrs in Iteresi, FqiIeS to in�,110y. Oc.
h�nrh-, z. ti,e City of E07,onds, 'A'Sh. �:s 0111cial-.
eth 0�'
a d arems Id. any an'l YI cla 'or da a Its
.1 I� S D111-1. T�—
Issu-2 of !his Or,—
It sha I ','of be "cled tC
In city oircinta-ce I
edify. a ve or rcd,,ce an, of a�,
I or -f I an-, v,ay jbC C.ty s ---ce rny ow-- I
A%':)L'4T
APPLJ�;ATJON APPROVAL
IF I hire.0y ac%nox:edgi Mat I have read - is a"o a " a
s correCt: Fine! !-I i .1 he
trtho,,Z�d .-t ( 1�, ovvne-. I ag.ee to Co-E, y ;'h LOY and
Sta�e j.,S nBI;,:at,hg �,. 3!,.ct on .,,C in co.ng tl-e ork -Iro,iZ TI,:I aol,' -Wior is not a pWrnit III
BEI -q,eby. o -11 te,e-pIOy0d.,n v-0- on or tt,f, Labor 5;q-1 by -�, Bo.!d,,, Ofi�c,a) or his
Cd d p 01 'he SI 01 %vaSh,nglon re:et ng !a Vlorfni- C.." pe'so. -d." are aid, and -ce,pt is
A
ATTENT11 11
IT IS UNI�ir"'I:UL TO USE OR OCaPY A E3U,LDING OR STRUCILIPZ
L:'�TIL A F NAL INS EC;TION KAS B::[:J %-ADE 4'n APPROVAL C,- 'cIcr
I p
A CEPT F;CA*.F Or' 017,11-)P�NCV WAS GEFN G-A'J'K� Ln`,G
pi"K ED-- GOLD - Ass ... c,
L-APTER a
A N
un
RM,
STZUCC. W. A"t4mteItu-z
PLAN
S C- LIZ-:- k ZO'
ARO^
J,
C6
E A
NOTES
s a I rbP,4� AAqr'z eeE�&-) PET -EIR r rFT
Y
FlZowr v.%,tzlD t-,ND 7-F-2-0 oeler 5 lvc- A&-W
FIE,
j2EAR— -/A.S?-DS FOP- G:LH f-LA� FLMNO�
Z�=-4EL0?tAB)JT (P.R.C>. 1-83)
APPROVED BY PLANNING
l=r)"awo's-
Voe� r=LNI TDL-A-C�C-: P,9.1> ?VZWIVE
-r44k-r �>Eir-iC5 MAY F-0�-P�04 tjPOtl -T44F
AP-EAS PI( MORG -r�4A��
RECEIVED
Cg3� r-oLjfZ-, l>zof>o;seD
(z) -rwo 77--E-r, A1�711CLC 17-
DEVELOPMENT SERVICES CTR.
CITY OF EDMONDS
52 6.,Qs> �3a,, #�-rmc-AED.
5q2EFT
FAF,
S' �*tel- 1 0 r- 'a
PLANNING DATA
SITE ADDRESS: �
PROJECT DESCRI
REDUCED SITE PLAN PROVIDED?: (Q / No
MAP PAGE: 1 0 & CORNER LOT: (Ye4% FLAG LOT: (Yes
C1 -52,
ZONINGi?tr-(p Py
3 D.- I—affICAL AREAS DETERMINATION #Q
LJ Study Required:
UWaiver
13 Conditional Waiver
PLAN CHK#:OLL- DE>_5
SEPA DETERMINATION:
Ll Fee
L3Checkl!St
U APO list w/ notarized form
U (Needed for 500 cubic yards of grading, Shoreline Area- site within 200 ft. of Puget Sound or Lake Ballinger)
Exempt
SETBACKS:
Required Setbacks:
— d Right Side-"h Rea**'
10 1 -9trM: 10' Left Si 9
Actual Setbacks:
-Street: 10' Left Side: Right Side: Rea
Street map checked for additional setback required? (Yes' No /3u
DETACHED STRUCTURES:
L3 ROCKERIES:
U FENCES/TRELLISES:
U BAY WINDOWS / PROJECTING MODULATION:
STAIRS / DECKS:
PARKING: Required: —Actual:
LOT AREA: 'a0 0 0
LOT COVEFMF=:
Calculations: Icnome,
BUILDING HEIGHT:
Datum Point:- t's Datum Elevation:
Maximum Aflowed: ___Actual Height:
A.D.U. CREATED?: Q /Yes)
SUBDIVISION:
LEGAL NONCONFORMING, LAND USE DETERMINATION ISSUED: (Yes
an eview B)r sia-
NewBPPlanningDataForm.DOC
CA File No:
Critic'a[-Areas;Check1i
Site Information (soils/ tqppgraphy/hydrol2gy/"`,_ eptation)
L6
1. Site Address/ Location;:; (p 4)' ELM PLACCE e!506�5, vy A�
-2. Property Tax Ac'c'o'u'ntN'umber: `7 A n C11(ne:) 1�5 C)�Co
Z
3._�,:�, AP',P'r 6xhinate Sipi..Sii6 Ucres -or s5uare feet):--`
.4. Is this site currently developed? yes; no.
X how is site develoved? P47AMMeb DaVSLZ�p EJJ-r SL b
6
5. Describe the general site"'iopograp*hy. Check all that apply.
Flat:- -,,.Iess.,than 5-feet elevation ch.an over entire site.
ge
Rolling: slopes on sit6:geheially"less than 1�% (a vertical rise of 10-feet over a horizontal
-feet).
distance *of 66
y: s opes present on site of more an'15 % and les 30% (a' vertical rise. of 10-feet
Hill th' s than
f
over a horizonwaistance of 33 td.66- e' 6 t).
Steep:... grades of greater than 30% present onSsite -`(a v'ertical,�.-irise of 10-feet over a horizontal
distance of less than 33-feet).
Other (pleas�:describe):
Depth:
6. Site contains areas: of year'round standing water- 1,10 Approx.
--A ep..:
7.',,.. Site contaihs,Aieas of seasonal standin D 'th
g water: pprox.
What season(s) of the year?
ay_:.` 00 of a water
8. Site1s M''the flo'o'd W* r "flo6d I course..
p am
9. Site contains a creek oran area where water.flows across the grounds surface? Flows are year-round?
Flows are seasonal? ----(What time� of year?
) /a," D
10. Site is primarily: forested meadow ;shrubs mixed R -E-C
urban landsciTi�d:(la wnsl-irubs ek)
-AAR 0 5 --K,21,
11. Obvious wetland is present on site: �30
Critical Areas Checklist.doc/3.19.2001
V ED
(P
City ofEdmon'ds-,
Development Service
Planning DivisiltEdifftl)
Phone: 425.771.0220.
Fax: 425.771.021AN 3 12.002
Date* Received:
City Receipt#:
'Critical Areas File
Critical Areas Checklist Fee:. $45.00
Date Mailed to ADDlicant:
The Critical Areas Checklist contained on this form is' to- A
property.,,pwner, or his/her authorized representative,,,
be filled out by any person' preparing a Development 'must fillouf the checklist, sign and date it, and submit it
Permit Application for the City of Edmonds prior to. to.the City. The City will,reviewAhe checklist, make a
his/her submittal of the application to the City. precursory site visit, and make a determination of the
The purpose of the Checklist is to enable City staff to subsequent steps necessary to complete a development
A U +U + -44 1 0-:+4 1 A - permit application.
VIM11111 11�; v;1 a11Y Fv L; a %,a %.;aa aLVI VL
may be, present on the subject property. The information
needed to complete the Checklist should be easily
available from, observations of the site or data available at
City Hall (Critical areas inventories, maps, or soil
surveys). RECEIVED
) AN 3 12002
Please submit a vicinity map, along with the signed copy
of this form to assist City staff in finding and locating the
s ecific piece of property 'described on this form. In
P,
addition, the applicant shall include other pertinent
information (e.g. site plan, topography map, etc.) or
studies in conjunction with this Checklist to assistant staff
in completing their preliminary assessment of the site.
.The undersigned applicant, andIr-iRelilitCRUEN', an assigns, in consideration on the processing of the application agrees
to release, indemnify, defend and hold the City of Edmonds harmless from any and all damages, including reasonable
attorney's fees, arising from any action or infraction based in 'whole or part upon false, misleading, inaccurate or
incomplete information furnished by the applicant, his/her/its agents or employees.
By my signature, I certify that the information and , exhibits herewith submitted are true and correct to the best of my
knowledge and that I am authorized to file this application on- the behalf of the owner as listed below.
SIGNATURE OF APPLIcANT/AGENT. DATE /— 3 /— 4) 2—
Property Owner's Authorization
By my signature, I certify that I have authorized the above Applicant/Agent to apply for the subject land use application,
and grant my permission for the public officials and the staff of the City of Edmonds to enter the subject property for the
purposes of inspection and posting attendant to this application.
SIGNATURE OF OWNER DATE 0 2—
Owner/Applitant:
R Q-L-
Name
& V Ci r--- L \,^ P t-IN, C-�
Street Address
11—==,kAomps
city State zip
Applicant Representative:
Name
Street Address
City State Zip
Telephone: 4'Z57- G-72- c)-82-a Telephone:
Email address (optional):
Email Address (optional):
Critical Areas Checklist.doe/3.19.2001
docritical Areas Checklisf� CA File No:
Site Information (soils/ topography/ hydrology/y.egetation)
1. Site Address/ Location: 614) EL�A PLACIE B-2KAnklis vyA� Lo-T
2. Property Tax Account Number: -7--2,g�, 4: nC73Q?'J'-NCXn!:pC0,4
3. Approximate Site Size (acres or square feet):
4. Is this site currently developed? Y, yes; no.
If yes; how is site developed? PL-Mmeb -pm eti-r (2 r-b
5. Describe the general site topography. Check all that apply.
Y, Flat: less than 5-feet elevation change over entire site.
Rolling: slopes on site :generally less than 15% (a vertical rise of 10-feet over a horizontal
distance of 66-feet).
Hilly: slopes present on site of more than 15% and less than 30% ( a vertical rise of 10-feet
over a horizontal distance of 33 to 66-feet).
Steep: grades of greater than 30% present on'site"fa vertical rise of 10-feet over a horizontal
distance of less than 33-feet).
Other (please describe):
6. Site contains areas of year-round standing water: o Approx. Depth:
7. Site contains areas of seasonal standing water: c3 Approx. Depth:
What season(s) of the year?
8. Site is in the floodw�ay V30 floodplain Of a water course.
9. Site contains a creek or an area where water flows across the grounds surface? Flows are year-round?
M 0 . __ Flows are seasonal? . - - . (What time of year?
10. Site is primarily: forested ;meadow ;shrubs mixed
urban landscaped (lawnshrubs etc)
11. Obvious wetland is present on site: V3 o
WAIYE
,:D
Critical Areas Checklist.doc/3.19.2001
STREET FILE
SUBSURFACE EXPLORATION AND
GEOTECHNICAL ENGINEERING REPORT
ELM PLACE,l LOTS 30,31,32536
Edmonds, Washington
PREPARED FOR
The Homeland Company
PROJECT NO. 8608-24
SEPTEMBER 1986
ASSOCIATEO
EARTH
zAr.al C,..C.S. INC
903 - 5th Avenue, Kirkland, Washington 98033
(206) 827-7701
SUBSURFACE EXPLORATION AND GEOTECHNICAL ENGINEERING REPORT
ELM PLACE RESIDENTIAL DEVELOPMENT
EDMONDS, WASHINGTON
1. PROJECT AND SITE CONDITIONS
1.0 INTRODUCTION
This report presents the results of our subsurface exploration, geologic,
and geotechnical engineering study for lot nos. 30, 31, 32, and 36 in the
Elm Place Residential Development in Edmonds, Washington. The proposed lot
locations and approximate locations of the explorations accomplished for
this study are presented on the Site and Exploration Plan, Figure 1. In the
event that any changes in the nature, design or location of the structures
are planned, the conclusions and recommendations contained in this report
should be reviewed and modified or verified as necessary.
1.1 Purpose and Scope
The purpose of this study was to provide subsurface data to be utilized in
the design and development of the above mentioned project. Our field study
included excavat ' ion of 5 exploration pits and performing geologic studies to
assess the type, thickness, distribution and physical properties of the
subsurface soils. Engineering studies were also conducted to determine the
type(s) of suitable foundation(s), allowable bearing pressures, and drainage
considerations. This report summarizes our current field work and offers
development recommendations based on our present understanding of the
project.
1.2 Authorization
Written authorization to proceed with this study was granted by Mr. Marty
Spadafora of The Homeland Company on 27 August 1986. Our study was
accomplished in general accordance w,ith our scope of work letter dated the
ame. This report has been prepared for the exclusive use of The Homeland
3mpany, and their agents, for specific application to this project in
:cordance with generally accepted geotechnical engineering and engineering
?ology practices. No other warranty, expressed or implied, is made. our
1
observations, findings, and conclusions are a means to identify and reduce
risks. Such risks are inherent to development on or near slopes; it should
be understood that slope,stability cannot be guaranteed.
2.0 PROJECT AND SITE DESCRIPTION
This report was completed with an understanding that one to two-story single
family residences with conventional wood -frame construction will be built on
the previously referenced lots. Daylight basements are planned for the
houses on lot nos. 30, 31, and 32. No basement is planned on lot no. 36.
The properties were situated near the west central portion of the Elm Place
Residential Development,. which is located to the southeast of the
intersection of Elm Street and 6th Avenue South in Edmonds, Washington.
Lots 30, 31, and 32, which are adjacent to each other, are approximately 40
feet by 60 feet and are situated to the southwest of a northwest -southeast
trending paved roadway. They are located on a hillside dipping downward to
the southwest with an approximate slope of 5H:lV (horizonta I :vertical).
This slope continues until a small pond, with a diameter on the order of 20
feet, is encountered just beyond the lot property lines. A rockery had been
p 1 aced around the perimeter of the pond. A 1 arge amount of f i I I has been
placed on these lots creating a steeper slope near the pond (1H:2V) and a
generally level area near the center of the lots. Total elevation change
across lots 30 and 31 was on the order of 10 to 15 feet. Lot 32 had an
elevation change of about 10 feet.
Lot 36, which is approximately 50 feet by 60 feet, is situated immediately
south of lots 30 through 32 and the pond. This lot was relatively level
except near the north toward the pond. At the time of our study, a large
fill pile was located on this lot.
3.0 SUBSURFACE EXPLORATION
our field stu - dy included excavating a series of 5 exploration pits to gain
information about the site. The various types of soils as wel 1 as the
depths where the soils or characteristics of the soils changed are indicated
on the exploration logs presented in the Appendix. The depths indicated on
the logs where soil conditions changed May represent gradational changes
between soil types in the field. Our exploration pits were approximately
located in the field by taping and pacing from known site features shown on
the site plan given to us by The Homeland Company (undated).
2
The conclusions and recommendations presented in this report are based on
the exploration pits completed for this study. The number, location, and
depth of the explorations were completed within site and proposal
constraints. Because of the nature of exploratory work below ground,
extrapolation of subsurface condit ions between -field explorations is
necessary. It should be noted that differing subsurface conditions may
sometimes be present due to the random nature of deposition and the
alteration of topography by past grading and/or filling. The nature and
extent of any variations between the field explorations may not become ful ly
evident until construction. If variations are observed at that time, it may
be necessary to reevaluate specific reconinendat ions in this report and make
appropriate changes.
3.1 Exploration Pits
Our field study included excavating a series of 5 exploration pits with a
tractor -mounted backhoe. Each of the pits penetrated between 10-1/2 and 14-
112 feet below present ground surface and permitted direct, visual
observation of subsurface conditions. The materials encountered in the
exploration pits were studied and classified in the field by a geotechnical
engineer or engineering- geologist. Al I exploration pits were-backfi I led
immediately after examination and logging. Selected samples were then
transported to our laboratory for testing as necessary.
4.0 SUBSURFACE C014DITIONS
Subsurface conditions on the lots were inferred from field explorations
accomplished for this study, visual reconnaissance of the site, and review
of applicable geologic literature. As shown on the field logs, tile
exploration holes generally encountered fill materials overlying natural
deposits.
4.1 Stratigraphy
Fill soils (those not naturally placed) were encountered in all exploration
pits. The fil 1 ranged in thickness from 7 feet in EP-4 to 13-1/2 feet in
EP-3. As noted on the exploration logs, the fil 1 general ly consisted of
loose to medium dense, moist, brown, silty, gravelly, fine to medium sand
with organics and large amounts of rubble and debris. These materials
probably originated from cut and fill operations on this and nearby sites.
Placement and compaction of the fil 1 materials was apparently not
documented. The specific nature, extent, and uniformity of such materials
3
are therefore uncertain and unpredictable. During the digging of the
exploration pits, I to 2 feet of caving off of the sides of the pits was
quite common.
Natural soils beneath the fill materials consisted for the most part of
medium dense to dense, saturated, gray, gravelly, medium to coarse sands
local ly overlain by 1 foot of an old topsoi I horizon. These sediments are
interpreted to be glacial drift derived from the Vashon Stade of the Fraser
Glaciation which was in this area approximately 15,000 years ago.
4.2 Hydrology
Ground water seepage was encountered in some of our exploration pits at the
time of our field study. The depth of seepage ranged from 10 feet to 14
feet. All of the coarse sands and gravels at the base of the exploration
pits were in a wet or saturated condition and probably represent the current
site water table. In exploration pi.ts 2 through 5, these sa.nds produced
free standing water. The existence of a pond adjacent to the lots is a good
indication that the local water table is not deep. Other shallower seepages
were located near an old topsoil layer and in the fi 11. These seeps
represent water that has temporarily migrated to or been stored at these
locations.
4
11. DESIGN RECO14MENDATIOIIS
5.0 INTRODUCTIO14
our exploration indicates that the lots in question (nos. 30, 31, 32, and
36) appear to be suitable for the proposed residential development. Due to
the extensive quantities of uncontrolled fill placed on the lots, the
bearing stratum is 8 to 14 feet below existing ground surface. Therefore, a
deep seated foundation system wil I be required for building support.
6.0 SITE PREPARATION
The placement and grading of the fil I on the lots has general ly prepared the
lots for residential construction with deep seated foundations. Excavation
of the basement areas should be undertaken with care since- the fi I I soils
are in a loose condition in many areas. Temporary cut slopes should not
exceed 1H:1V (horizontal :vertical). Even at this angle, some sloughing
should be anticipated. Excavated material stockpiled on site will be suject
to erosion and should be protected.
7.0 FOUNDATIONS
Due to the presence of 8 to 14 feet of uncontrolled fill and old topsoil in
the areas of our exploration pits, it wil I be necessary to support the
buildings on deep seated foundations which bear on the underlying, natural,
medium dense to dense, grey, gravelly sands. Several alternative foundation
designs may be utilized as discussed below.
7.1 Drilled -in Piers
Dril led -in concrete piers wil I provide suitable foundation support if
extended through the fi I I and embedded a minimum of 6 feet into the
underlying natural soils. Piers with a diameter of 14 inches and properly
reinforced wil I be capable of supporting loads on the order of 8 tons per
pier. The actua I depth and load carrying capacity of each pier wi I I be
adjusted in the f ield during i nsta I I at ion by the Engineering
Geologist/Geotechnical Engineer.
The utilization of this foundation system requires that the soils will stay
open after auger withdrawal while concrete is being placed. If the holes
wi 11 not stay open, it may be necessary to case the ho I es. In addition, if
excess water seeps into the hole during and immediately following augering,
it may be necessary to use a flexible drop chute or concrete pump with hose
Lo the bottom of the hole to assure that the water is adequately displaced.
Based on observations during our field exploration, it is our opinion that
the augered holes will generally stay open, although a few may need casing.
Water seepage near the bottom of the holes may present minor problems
especially with the downslope piers.
7.2 Auger Cast -In -Place Piles
Cast -in -place concrete piling (Augercast TM) may also be used for foundation
support. We recommend that the placement of all piles be accomplished by a
contractor' experienced in their installation. The actual total length of
each pile may be adjusted in the field based on required capacity and
conditions encountered during drilling. Since completion of the pile takes
place below ground, the judgement and experience of the Geotechnical
Engineer must be used as a basis for determining the required depth and
acceptability of each pile. Consequently, use of the presented pile
capacities in the design requires that all piles be inspected by a qualified
Geotechnica) Engineer or Engineering Geologist from our firm who can
interpret and collect the installation data and examine the contractor's
operations. Associated Earth Sciences, Inc. acting as the owner's field
representative, would determine the required lengths of pi les and keep a
record of the same.
AugercastTM pi I es with a minimum diameter of 14 inches wi 11 be capabl e of
supporti ng 15 tons per pi I e when embedded a mi nimurn of 3 f eet i n to tile
under I ying natura I , grave 11 y sand sediments.
Although this type of installation is usually significantly more expensive
than dr i 11 ed- in piers, i t e I iminates the need for cas ing or concrete pumps
due to caving or water conditions.
7.3 Rock Trenches
The third presented foundation alternative for this site is rock trenches.
This system also has the advantage of being relatively low cost and can be
performed by the general contractor. Rock trenches have been utilized with
6
favorable success in many soil types around the Puget Sound area. The
trenches should have a minimum width of 4 feet and be excavated down to the
medium dense to dense, natural soils. Because of the potential for caving,
the actual trench width may be greater than specified. It would be
appropriate to backfill the trenches as the excavation proceeds to minimize
cav ing. The use of a larger, track -mounted backhoe with the teeth covered
will greatly speed trench excavation over the use of a conventional, rubber -
tired backhoe.
To determine when suitable bearing has been achieved and to verify proper
rock placement, the Geotechnical Engineer/Engineering Geologist must be
present on a ful 1-time basis during footing trench excavation and backfil 1.
A pump may be required to control seepage so that the bearing level can be
visually determined. After the bearing stratum has been reached, the trench
may be backfil led. We recommend the use of 1 to 2 inch size, crushed rock
for backfil 1. The crushed rock must be tamped into place to achieve a
tightly -packed mass; this may be done with either a "Hoepac" type compactor
mounted on the backhoe or with the bucket of the backhoe itself. Staging
areas should be maintained so that the rock is not contaminated by mud prior
to placement in the trench. Equipment access to trench locations should
also be maintained.
Spread footings may be used for building support when founded on rock
trenches properly constructed and bearing on the lower sands. Masonry
fireplaces are settlement sensitive and should be supported by the lower
sands as we] 1. . Footings which bear on approved rock trenches may be
designed for an allowable bearing pressure of 2,000 psf including both dead
and live loads. Perimeter footings should be buried at least 18 inches into
the surrounding soil for frost protection. Interior foot'ings need only
extend 12 inches below adjacent grade. However, a] I footings or rock
trenches must penetrate to the prescribed bearing. stratum and no footing
should be founded in or above loose, organic, or existing fil I soils. In
addition, al 1 footings should have a minimum width of 14 inches.
Al I of the above given design loads may be increased by one-third for short
term wind or seismic loading.
Anticipated settlement of footings founded on pile or pier foundations
should be less than I inch. For footings founded on rock trenches, the
settlement should be on the order of 112 inch. However, disturbed material
not removed from footing trenches prior to concrete placement could result
in increased settlements.
7
8.0 FLOOR SUPPORT
Slab -on -grade floors are not recommended for these lots due to potential
settlement problems associated with the extensive thickness and variability
of the fill soils. Crawlspace type construction with internal footings
founded on piles, piers or rock trenches will minimize problems associated
with the sites and should be the preferred construction method. Tile soi I
be low the f 1 oor system shou 1 d be covered with a vapor barrier to reduce
potential dampness. Adequate ventilation must be provided to prevent the
buildup of methane gas below the structures.
9.0 PASSIVE RESISTANCE AND FRICTION FACTORS FOR GRADE BEAMS
To obtain passive resistance against lateral translation, the grade beams
must be backfil led with structural fill compacted to 95 percent of the
Modified Proctor Maximum Density using ASTM:D 1557 as the standard. If
grade beams are placed on grade and then backfilled, the top of the backfill
must be horizontal and extend outward from the beam for a minimum lateral
distance equal to three times the height of the backf i 11 , before tapering
down to grade. With backfill placed as discussed, beams may be designed for
passive resistance against lateral translation using an equivalent fluid
equal to 250 pounds per cubic foot (pcf). This value includes a factor of
safety equal to 3 in order to minimize the amount of movement necessary to
generate passive resistance. The friction coefficient for grade beams will
be minimal on the organic fill.
10.0 LATERAL WALL PRESSURES
Al 1 backfil I behind walls or around foundation units should be placed as per
our recommendat ions for structural fil I and as described in this section of
the report. Backfil led wal ls which are free to yield laterally at least 0.1
percent of their height, may be designed using an equivalent fluid equal to
35 pounds per cubic foot (pcf). Ful ly restrained rigid (basement -type)
wal ls which cannot yield should be designed for an equivalent fluid of 50
pcf.
The lateral pressures presented above are based on the conditions of a
uniform, horizontal backfil 1 consisting of free -draining sand and gravel,
compacted to 90 percent of maximum density using ASTM:D 1557 as the
standard. A h i gher degree of compact i on i s not recommended as th i s wi 1 1
N
N�
I
J
0 0
increase the pressure acting on the wall. Surcharges from adjacent
footings, heavy construction equipment, vehicles or sloping ground must be
added to the above values. Perimeter footing drains should be provided for
al I retaining wal Is as discussed under Section 11.0, Drainage
Considerations.
If the onsite soils are used for backfill, an equivalent fluid equal to 54
pcf should be used for the yielding condition. Since the wall will be
restrained prior to backfil ling, it should be designed for an equivalent
fluid equal to 72 pcf where onsite soil wil 1 be used for backfil 1. These
values do not include hydrostatic pressures. Because onsite fill materials
are not free -draining, it is imperative that proper drainage be provided so
that hydrostatic pressures do not develop against the wal 1. This wi I I
involve installation of a blanket drain using imported gravel ful 1-height
against the walls. If a structure is below the water table, it must be
designed for hydrostatic uplift and lateral pressures as well as soil
pressures*. In this case, restrained walls should be designed using an
equivalent fluid equal to 90 pcf to account for soil and water pressures.
11.0 DRAINAGE CONSIDERATIONS
Al I retaining and footing wal Is should be provided with a drain at the
footing elevation (unless supported on rock trenches). Rock trenches [nay be
used as footing drains if they daylight or can drain by gravity away from
the building. Drains should consist of perforated pipe enclosed in a pea
gravel, sand -free trench. They'should be constructed with sufficient
gradient to al low gravity discharge away from the building. Roof and
surface runoff should not discharge into the footing drain system but should
be handled by a separate tightline drain. In planning, exterior grades
adjacent to wal Is should be sloped downward away from the structure to
achieve surface drainage.
We are available to provide geotechnical engineering and monitoring services
during constriuction. The integrity of the foundation depends on proper site
preparation and construction procedures, and engineering decisions may have
to be inade in the field in the event that localized variations in subsurface
conditions become apparent.
Thank you for this opportunity to be of service. We trust our findings,
conclusions and recoinnendat ions will be helpful in the successful completion
Z
of your project. Should you have any questions or require further
assistance, please fee-1 free to contact us.
Sincerely,
ASSOCIATED EARTH SCIENCES, INC.
G,jry AAFlowers, P.G.
Principal
Gary T.Robdell, P.E., P.G.
Principal
GAF/jaw
8608-24A
L 0
y4;
§
P
10NAL
10
I
0
ZI 141 3 T
Ap/0 E P- -5
POId
ale:
50
"'N
-50
ER I
;51
EP-2
.3Z
ER 9
.00�
//o-
. /1100,
O"e- - ---�2�6
-20
I � le 700 1
Figure 1: Site and Exploration Plan
Elm Place
Lots 30, 31, 32, and 36
Edmonds, Washington
8608-24 lAugust 1986