HomeMy WebLinkAboutSEPA EPIC-334-86 - SCHNEIDER HOMES - MAPLETREE PARK SUBDIVISIONSCHNEIDER HOMES, INC.
MAPLETREE PARK
SUBDIVISION INTO 14
SINGLE FAMILY LOTS
SW CORNER INTERSECTION
OF 65T" AVE. S. & 151ST ST.
EPIC 334 -86
WAC 197 -11 -970
MITIGATED
DETERMINATION OF NONSIGNIFICANCE
Description of Proposal Mapletree Park Subdivision of 4.80 acres
into 14 single family lots of 12,000 square feet.
Proponent Schneider Homes. Inc.
Location of Proposal, including street address, if any NE 23 -23 -4
`southwest corner of the intersection of 65th Avenue S. and 151st Street
Lead Agency: City of Tukwila File No. EPIC- - 334 -86
The lead agency for this proposal has determined that it does not have a probable
significant adverse impact on the environment. An environmental impact statement
(EIS) is not required under RCW 43.21C.030(2)(c). This decision was made after
review of a completed environmental checklist and other information on file with the
lead agency. This information is available to the public on request.
C[ There is no comment period for this DNS
This DNS is issued under 197 -11- 340(2). Comments must be submitted by
July 23. 1986 . The lead agency will not act on this
proposal for 15 days from the date below.
Responsible Official Brad Collins
Position /Title Planning Director
Phone 433 -1845
Address 6200 Southcenter Boulevard, Tukwila, WA 98188
Date -7-1-8 Signature e' -7k Ct L
You may appeal this determination to the City Clerk at City Hall, 6200 Southcenter
Boulevard, Tukwila, WA 98188 no later than 10 days from the above date by written
appeal stating the basis of the appeal for specific factual objections. You may be
required to bear some of the expenses for an appeal.
Copies of the procedures for SEPA appeals are available with the City Clerk and
Planning Department.
FM.DNS
City of Tukwila
6200 Southcenter Boulevard
Tukwila Washington 98188
(206) 433 -1800
Gary L. VanDusen, Mayor
MITIGATION MEASURES
DNS FOR
MAPLETREE PARK
1. Native protection easement must remain open and in its natural state with a
fence erected along the west property line prior to final plat approval.
Maintenance for fence shall be contained in subdivision covenants.
2. Street and utilities must be constructed to minimum City standards, including
80 -foot diameter cul -de -sacs, and be dedicated to City upon completion and
approval of Public Works Department. Improvement will include street lights
and sidewalks.
3. An engineered grading plan for permit application and review will be required.
4. Retaining walls (no rockeries will be in excess of four (4) feet in height)
will be designed with assumed hydrostatic pressures and slope surcharge.
5. Stripped organics will be removed from the site during site preparation.
-CITY OF TUKWILA
CENTRAL PERMIT SYSTEM
•
CN - 8(o -i9 i
EPIC- 334 -8(0
FILE 810-31 -SUES
ENVIRONMENTAL REVIEW ROUTING FORM:
TO: Q BLDG -PLNG -d (] P.W. (j FIRE n POLICE (i P & R
PROJECT JC /YLucibt) Ff v � 61/Kb ,
LOCATION S lik) C o Vt•Q,t) S, I S I Sf/ oS b-Pitttauf. FILE NO.
DATE TRANSMITTED 61171 g(U 41ESRONSE REQUESTED BY .?//g
RESPONSE RECEIVED
STAFF COORDINATOR
THE ATTACHED ENVIRONMENTAL CHECKLIST WAS RECEIVED REGARDING THIS PROJECT. PLEASE
REVIEW AND COMMENT BELOW TO ADVISE THE RESPONSIBLE OFFICIAL REGARDING THE THRESHOLD
DETERMINATION. THE ENVIRONMENTAL REVIEW FILE IS AVAILABLE IN THE PLANNING DEPART-
MENT THROUGH THE ABOVE STAFF COORDINATOR. COMMENTS REGARDING THE PROJECT YOU WISH
CARRIED TO THE PLANNING COMMISSION, BOARD OF ADJUSTMENT, AND CITY COUNCIL SHOULD BE
MADE ON THE ATTACHED CENTRAL PERMIT SYSTEM ROUTING FORM.
ITEM COMMENT
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COMMENTS PREPARED BY 403
C.P.S. Form 11
CITY OF TUKWILA
CENTRAL PERMIT SYSTEM
•
• CN -8(0- 19
EPIC- 334 -S(o
FILE 810-31 -SUE
ENVIRONMENTAL REVIEW ROUTING FORM:
TO: Q BLDG 0 PLNG 0 P.W. L- .FIRES n POLICE n P & R
PROJECT oAt43 1 61/14b
LOCATION $ &) C crvu' 1) Si 1 S I Sf/ 6vs x}V S • c�1,I�LS�LQrf, FILE NO.
DATE TRANSMITTED 6// 7/g4) SRESPONSE_REQUESTED -BY (Dlo?4�gSo
RESPONSE RECEIVED
STAFF COORDINATOR
THE ATTACHED ENVIRONMENTAL CHECKLIST WAS RECEIVED REGARDING THIS PROJECT. PLEASE
REVIEW AND COMMENT BELOW TO ADVISE THE RESPONSIBLE OFFICIAL REGARDING THE THRESHOLD
DETERMINATION. THE ENVIRONMENTAL REVIEW FILE IS AVAILABLE IN THE PLANNING. DEPART-
MENT THROUGH THE ABOVE STAFF COORDINATOR. COMMENTS REGARDING THE PROJECT YOU WISH
CARRIED TO THE PLANNING COMMISSION, BOARD OF ADJUSTMENT, AND CITY COUNCIL SHOULD BE
MADE ON THE ATTACHED CENTRAL PERMIT SYSTEM ROUTING FORM.
ITEM COMMENT
1514%
GLA,C,P j//,.,. - .4.5A 6t4;,. drh-
DATE P ' /9, F6, COMMENTS PREPARED BY
C.P.S. Form 11
CITY OF TUKWILA
CENTRAL PERMIT SYSTEM
•
• CN -e(v-19 1
EPIC- 334.8(0
FILE s'to-31 -5UE
ENVIRONMENTAL REVIEW ROUTING FORM:
TO: 10 1M OBLDG4 J PLNG n P.W. n FIRE n POLICE (j P & R
PROJECT j4CIIAUJ LLAJ rTUYv1 -e.,0 � J'ylC, ,
LOCATION SW C Of {�I P.(1 S, S sf/ dos AV S (11AIaQIf, FILE NO.
( //77R)
STAFF COORDINATOR RESPONSE RECEIVED (.1ei3 /ii(o
DATE TRANSMITTED
IRESPONSE REQUtSTED'B'Y -:itORAMV
THE ATTACHED ENVIRONMENTAL CHECKLIST WAS RECEIVED REGARDING THIS PROJECT. PLEASE
REVIEW AND COMMENT BELOW TO ADVISE THE RESPONSIBLE OFFICIAL REGARDING THE THRESHOLD
DETERMINATION. THE ENVIRONMENTAL REVIEW FILE IS AVAILABLE IN THE PLANNING DEPART-
MENT THROUGH THE ABOVE STAFF COORDINATOR. COMMENTS REGARDING THE PROJECT YOU WISH
CARRIED TO THE PLANNING COMMISSION, BOARD OF ADJUSTMENT, AND CITY COUNCIL SHOULD BE
MADE ON THE ATTACHED CENTRAL PERMIT SYSTEM ROUTING FORM.
ITEM COMMENT
DATE l lo COMMENTS PREPARED BY
C.P.S. Form 11
CITY OF TUKWILA
CENTRAL PERMIT SYSTEM
•
CN -S(9-19
EPIC' 334 -8(0
FILE 5(-31 -SUE
ENVIRONMENTAL REVIEW ROUTING FORM:
TO: [] BLDG Q PLNG n P.W. n FIRE n POLICE INIFA &`'R
PROJECT ,}j()/(1/10-ti.c iYn_t43 + \j/44(, ,
LOCATION SW CDr{&PA) 5,1s1 S- t / (05 3v S • t14,tma ±. FILE NO.
o / / 7 /R(,
DATE TRANSMITTED
STAFF COORDINATOR
tRNI10NSE'REQ.UESTED BYE °' �' Nt ¢'
RESPONSE RECEIVED
THE ATTACHED ENVIRONMENTAL CHECKLIST WAS RECEIVED REGARDING THIS PROJECT. PLEASE
REVIEW AND COMMENT BELOW TO ADVISE THE RESPONSIBLE OFFICIAL REGARDING THE THRESHOLD
DETERMINATION. THE ENVIRONMENTAL REVIEW FILE IS AVAILABLE IN THE PLANNING DEPART-
MENT THROUGH THE ABOVE STAFF COORDINATOR. COMMENTS REGARDING THE PROJECT YOU WISH
CARRIED TO THE PLANNING COMMISSION, BOARD OF ADJUSTMENT, AND CITY COUNCIL SHOULD BE
MADE ON THE ATTACHED CENTRAL PERMIT SYSTEM ROUTING FORM.
ITEM COMMENT
DATE cliff e,
COMMENTS PREPARED BY
C.P.S. Form 11
CITY OF TUKWILA •
CENTRAL PERMIT SYSTEM
• CN -S(9-191
EPIC- 334-8(0
FILE -to-31-SUE
ENVIRONMENTAL REVIEW ROUTING FORM:
TO: 0 BLDG Q PLNG , J P.W. Q FIRE �_':ie7POL:ICE1 n P R
PROJECT ;� ()1(1/10A141/1,...) f-fb V Lt0 � J4/1 ,
LOCATION SW CDYV1.j) 5, 151 Sf / 121-V S•lAtt.Sluf, FILE NO.
DATE TRANSMITTED
61/7/ gb
cRESPONSE- REQUESTED_.BY (0/4-1g-'(,)
STAFF COORDINATOR RESPONSE RECEIVED (ply 5/0'b
THE ATTACHED ENVIRONMENTAL CHECKLIST WAS RECEIVED REGARDING THIS PROJECT. PLEASE
REVIEW AND COMMENT BELOW TO ADVISE THE RESPONSIBLE OFFICIAL REGARDING THE THRESHOLD
DETERMINATION. THE ENVIRONMENTAL REVIEW FILE IS AVAILABLE IN THE PLANNING DEPART-
MENT THROUGH THE ABOVE STAFF COORDINATOR. COMMENTS REGARDING THE PROJECT YOU WISH
CARRIED TO THE PLANNING COMMISSION, BOARD OF ADJUSTMENT, AND CITY COUNCIL SHOULD BE
MADE ON THE ATTACHED CENTRAL PERMIT SYSTEM ROUTING FORM.
ITEM COMMENT
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15 L s i d-/Dr 6 gr./4- S
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DATE COMMENTS PREPARED BY
c7/-
C.P.S. Form 11
-b i
JUN 13 1986
CITY OF TOKW LA
PLANNING DEPT.
Purpose of Checklist:
ENVIRONMENTAL CHECKLIST
Control No. C:N 8(o- /9/
Epic File Ib. Ep/C- 334 -g
Feet /06, 6o Receipt No. j l,,
The State Environmental Fblicy Pct (SEPA), chapter 43.21C RC;W, 'requires all
governmental agencies to consider the environmental impacts of a proposal before making
decisions. An erry iron mental impact statement (EIS) must be prepared for all proposals
with probable significant adverse impacts on the quality of the environment. The
purpose of this checklist is to provide information to help you and the agency identify
impacts from your proposal (and to reduce or avoid impacts from the proposal, (if it
can be done) and to help the agency decide whether an EIS is required.
Instructions for Applicants:
This environmental checklist asks you to describe some basic information about your
proposal. GDverrmental agencies use this checklist to determine whether the
environmental impacts of your proposal are significant, requiring preparation of an
EIS. Answer the questions briefly, with the most precise information known, or give
the best description you can.
You must answer each question accurately and • carefully, to the best of your
knowledge. In most cases, you should be able to answer the questions from your own
observations or project plans without the need to hire experts. If you really do rot
know the answer, or if a question does not apply to your proposal, write "do not know"
or "does not apply". Complete answers to the questions now may avoid unnecessary
delays later.
Same questions ask about goverrrnental regulations, such as zoning, shoreline, and
landmark designations. Answer these questions. if you can. If you have problems, the
goverrmental agencies can assist you.
The checklist questions apply to all parts of your proposal, even if you plan In do
than pier a period of time or on different parcels of land. Attach any additional
information that will help describe your proposal or its environmental effects. The
agency to which you submit this checklist may ask you to explain your answers or
provide additional information reasonably related to determining if there may be
significant adverse impact.
Use of checklist for nonproj ect proposals:
Complete this checklist
answered "does not apply."
ACTIONS (Part D).
Fbr ronproj ect actions,
"applicant" , and "property
"affected geographic area,"
A. BACKGROUND
for nonproject proposals, even though questions may be
In ADDITION, canplete the SUPPLEMENTAL SHEET FOR NDNPRQJECT
the references in the checkl ist to the words "proj ect" ,
or site" should . be read as "proposal," "proposer," and
respectively.
1. Name of proposed project, if applicable: Mapletree Park
2. Name of applicant: Schneider Hones, Inc.
• •
3. Address and phone number of applicant and contact person:Applicant: Schneider
Homes, Inc., 6510 Southcenter Blvd., Tukwila, IAA., 98188, 248 -2471; Contact Person:
Jim Egge, Group Four, Inc., 19502 56th Ave. W., Lynnwood, VA., 98036, 775 -4581
4. Date checklist pared : June 1986
5. Agency requesting checklist: CITY OF TUKWILA
6. Proposed timing or schedule (including phasing, if applicable) : Fall 1986, subject
to market conditions.
7..Do you have any plans for future a3ditions, expansion, or further activity related
to or connected with this proposal? If yes explain. No.
8. List any env ironnental information you know about that has been prepared, or will
be prepared, directly related to this proposal. An environmental checklist and associ-
ated information was prepared for this site and the property to the south in November
1985.
9. Do you know whether applications are pending for governnental approvals of other
proposals directly affecting the property covered by your proposal? If yes explain.
None to our knowledge.
10. List any government approvals or permits that will be needed hor your proposal, if
known. Preliminary and final plat approval, sewer and water connections, grading per-
mit, building permits.
11. Give brief, complete description of your proposal, incluuing the proposed uses and
the size of the project and site. There are several questions later in this checklist
that ask you to describe certain aspects of your proposal. You do not need bo repeat
those answers on this page. (Lead agencies may modify this form to include alditional
specific information on project description.) The proposal is for a preliminary plat
of 14 lots on the 4.8 acre site.
12. Location of the proposal. Give sufficient information for a person to understand
the precise location of your proposed project, 'including a. street address, if any, and
.section, township, and range, if known. If a proposal would occur over a range of
area, provide the range or boundaries of the site(s) . Provide a legal description,
site plan, vicinity map, and topographic map, if reasonably available. While you
should submit any plans required by the agency, you are not required bo duplicate maps
or detailed plans submitted with any permit applications related to this checklist.
The site is generally located north of Southcenter shopping mall, in the southwest
quadrant of the S. 151st St. /65th Ave. S. intersection.
TO BE COMPLETED BY APPLICANT
B. ENVIRONMENTAL ELEMENTS
1. Earth
a. General description of the site (circle one): Fla , rollin
hilly, steep slopes, mountainous, other
b. What is the steepest slope on the site (approximate percent
slope)? Slopes of approximately 80% exist along the east slopes of
the ravine located along, the western boundary of the site.
c. What general types of soils are found on the site (for example,
clay, sand, gravel, peat, muck)? If you know the classification of
agricultural soils, specify them and note any prime farmland.
Based on the 1973 Soil Survey for King County, soils on -site are
predominately Urban Land (UR). Urban Land is•soil that has'been
modified by disturbance of the natural layers with additions of
fill material several feet thick.
d. Are there surface indications of history of unstable soils in the
immediate vicinity? If so, describe. No.
e. Describe the purpose, type,-and approximate quantities of any
filling or grading proposed. Indicate source of fill. Road and
building sites would be cleared; graded, filled and compacted as
necessary to achieve proper grade transition, drainage and struc-
tural stability. A balance between cut and fill operations would
be sought, thereby reducing the need to import fill materials.
EVALUATION FOR
AGENCY USE ONLY
EVALUNTION FOR
AGENCY USE ONLY
f. Gould erosion occur as a result of clearing, construction, or
• use? If so, generally describe. During construction, the potential
for increased erosion would be present. Following construction,
erosion potential would decrease when cleared areas become revege-
tated.
g. About that percent of the site will be covered with impervious
surfaces after project construction (for example, asphalt or
buildings)? Approximately 32% of the site would be covered with
impervious surfaces after project construction.
h. Proposed measures to reduce or control erosion, or other
impacts to the earth, if any: Temporary measures to control erosion
could include sedimentation ponds, filter fences and diversion
swales; permanent measures could include landscaping, piping and
armoring of outfall areas,.
2. Air
a. hat types of emissions to the air would result from the
proposal (i.e., dust, automobile, odors, industrial wood smoke)
.during construction and When the project is completed? If any,
generally describe and give approximate quantities if known.
During construction activities there would be increased exhaust and
dust particle emissions to the ambient air. Objectionable odors
e caus-. .y t o roo ing o omes or t o paving o streets.
After construction the principle. source of pollution would-be ex-
haust from vehicular traffic. The increase in automobiles associa-
te with`the development would contribute CO, NO and SO emissions
to t e - •ient air. Firep aces insta in omes wou
smoke to the ambient air.
b. Are there any off -site sources of emissions or odor that may
affect your proposal? If so, generally describe. Other residential
developments in the vicinity of the proposal Would be sources of
emissions and odors similar to those generated by, the proposal.
Exhaust from vehicular traffic on.adjacent roadways would be a con-
tinual source of air pollution..
wou
-•
contra
ute
c. Proposed measures to reduce or control emissions or other
impacts to air, if any: Should construction activities be under-
taken during dry , •-riods p- `eriodic watering, if deemed necessary,
woul. .- ..ert en. Automo•ile emissions Woul 'r ulat
Was }ngton State Department o Licensing.
• •-
• •
TO BE COMPLETED BY APPLICANT
3.Water
a. Surface:
EVALUATION FOR
AGENCY USE ONLY
1) .Is there any surface water body on or in the immediate
vicinity of the site (including year-round and seasonal
streams, saltwater, lakes, ponds, wetlands)? If yes,
describe type and provide nanes. If appropriate, state
What stream or river it flows into. A drainage .course collecting
water from northwest of the site daylights in the ravine area adja-
cent to the west property boundary.
2) Will the project require any work over, in, or a3j acent to
(within 200 feet) the described waters? If yes, please
describe and attach available plans. Yes, construction on Lots 3,
4, 5 and 6 could occur within 200 feet of the drainage course.
3) Estimate the amount of fill and dredge material that would
be placed in or removed from surface water or wetlands and
indicate the area of the site that would be affected. Indicate
the source of fill material. N/A
4) Will the proposal require surface water withdrawals or
diversions? Give general description, purpose, and approxi-
mate quantities, if known. No major surface water withdrawls or
diversions would be performed with the proposal.
5) Does the proposal lie within a 100 -year floodplain? if so,
note location on the site plan. No.
6. Des the proposal involve any discharges of waste material
to surface waters? If so, describe the type of waste and
anticipated volume of discharge. Through the construction of road-
ways and residences, the site's, natural runoff pattern would be
modified. Post development storm water runoff containing some
pollutants (primarily oil and debris washed from the road system)
would be collected by the storm drainage system. Restricted ori-
fice and catch basins with petroleum separators' would be installed
in the storm water system to control pollution of surface water.
The majority of the storm water from impervious surface§ on. site
would be detained in a pipe system and ultimately discharged into
the existing storm system to the east of the site. in 65th Ave. S.
-4-
TO BE COMPLETED BY APPLICANT EVALUATION FOR
AGENCY USE ONLY
b. Ground
• 1). Will ground water be withdrawn, or will water be discharged
to ground water? Give general description, purpose, and
approximate quantities if. known. Alteration to the direction or
rate of flow.of ground water due to roadway cut and fill should be
localized on -site only. Release of ground water onto adjacent pro-
perties should not vary from the present condition.
2) Describe waste material that will. be discharged into the
'ground from septic tanks or other sources, if any (for exanple:
Domestic sewage; industrial, containing the following chemi-
cals ; agricultural; etc) . Describe the general size of the
system, the number of such systems, the number of houses to
be served (if applicable) , or the number of animals or humans
the system(s) are expected to serve. There would be no major
sources of waste material to be discharged into the ground water,
since the proposal would be on sewers. •
c. Water Runoff (including storm water) :
1) Describe the source of runoff (including storm water) and
method of collection and disposal, if any (including quanti-
ties, if known) . Where will this water flow? Will this water
flow into other waters? If so, describe. Runoff from the proposal
would be generated by building roofs, driveways, sidewalks, patios
and roadways. This water would be collected and stored by the
storm drainage system and ultimately released into the existing
storm system to the east of the site in 65th Ave. S.
2) Could waste materials enter ground or surface waters? If so,
generally describe. Refer to Surface Water Response 6. Water solu-
able household and yard care products could also enter ground or
surface waters.
d.'Proposed measures to reduce or control surface, ground, and
runoff water impacts, if any: Refer to Surface Water Response 6.
TO BE COMPLETED BY APPLICANT
4. Plants
a. Check or circle
-X- deciduous tree:
-X- evergreen tree:
-X -shrub s
- X -grass
- -- pasture
- - -crop or grain
-X-wet soil plants:
other .
iype. s of
alde
Cf�r,(cedar
•
etation found on the site:
aspen, other
pine, other
cattail, buttercup, bullrush, skunk cabbage,
EVALUATION FOR
AGENCY USE ONLY
- -water plants: water lily, eelgrass, milfoil, other
- -other types of vegetation
b. at kind and anount of vegetation will be renoved or altered?
Approximately 43% of the vegetation on -site would be cleared for
building site, roadway and utility construction.
c. List threatened or endangered species known to be on or near
the site. None to our knowledge.
d. Proposed landscaping, use of native plants, or other measures
to preserve or enhance vegetation on the site, if any: Development
would reduce existing vegetation, although as much native vegeta-
tion as possible would be retained during construction. A 20 foot
native growth protection easement would be provided along the
site's western boundary, thereby protecting the existing drainage:
course. Private, yards would be landscaped with lawns and ornamen -.
tal and native plant species.
5. Animals
a. Circle any birds and animals which have been observed on or
near the site or are known to be on or near the site:
birds: hawk, heron, eagle,so birds,- others ......
mammals: deer, bear, elk, beaver, dther__pnall mammal.. .
fish: bass, salmon, trout, herring, shellfish, other....
b. List any threatened or endangered species known to be on or
near the site. None to our knowledge.
TO BE COMPLETED BY APPLICANT EVALUATION FOR
AGENCY USE ONLY
c. Is the site part of a migration route? If so, explain.
Not to our knowledge.
d. Proposed measures to preserve or enhance wildlife, if any:
Wildlife would be preserved by preserving as much existing ve-
getation as practical during construction. The 20-foot native
growth protection easement along -the sites western boundary
would preserve wildlife in the drainage course`area. Landscap-
ing of private yards could include some native species.
6. Energy and Natural Resources
a. What kinds of energy (electric, natural gas, oil, wood stove,
solar) will be used to meet the completed project's energy
needs? Describe whether it will be used for heating , .
manufacturing, etc. Electricity and natural gas would be the
primary , sources of energy for the proposal, and would-be used
forheating, ~lighting and other miscellaneous household pur-
poses. Woodburning and passive solar gain would be secondary
sources of heat.
b. Would your project affect the potential use of solar energy by
adjacent properties? If so, generally describe. No.
c. What kinds of energy conservation features are included in . the
plans of this proposal? List other proposed measures to reduce
or control energy impacts, if any: Energy conservation features
would be per the_Energy Code and the choice of the individual
residents.
7. Environmental Health
a. Are there any environmental health hazards, including exposure
to toxic chenicals, risk of fire and explosion, spill, or
' hazardous Haste, that could occur as a result of this proposal?
Not to our knowledge.
1) Describe special emergency services that might be required.
No special emergency services would be required by the
proposal.
2) Proposed measures to reduce or control environmental health
hazards, if any: None proposed . ,
• •
PD BE COMPLETED BY APPLICANT EVALUATION FOR
ACENCY USE ONLY
b. H ise
1) What types of noise exist in the area Which may affect your
project (for example: traffic, aircraft, equipment, operation,
other)? Noise from adjacent roadways and residential develop-
ments could have an impact on the development.
2) What types and levels of noise would be created by or
associated with the project on a short-term or a long -term
basis (for example: traffic, construction, operation, other)?
Indicate that hours noise would cane from the site. Noise
levels would be intermittently high throughout construction,
but should be limited to normal waking hours. After construc-
tion, residential activity and traffic noise'created by daily
vehicular trips would increase the ambient noise level.
3) Proposed measures to reduce or control noise impacts, if any:
Houses could be set back from potential noise sources_and exis-
ting perimeter vegetation could be retained and enhanced with
additional plantings to provide aesthetic and acoustic control.
8. Land and Shoreline Use
a. What is the current use of the site and adjacent properties?
The site is currently occupied by a single family residence.
Properties to the north and south are in large parcel, single
family ownerships; to the west is a short plat and Sunwood
Condominiums; to the east are Maple Crest Apartments, Parkview
Apartments and Canyon Estates Condominiums.
b. Has the site been used for agriculture? Is so, describe. No.
c. Describe any structures on the site. A single family residence.
d. Will any structures be demolished? If so, what? Yes, the
single family residence.
e. What is the current caning classification of the site? R -1 -12.0
f. What is the current comprehensive plan designation of the site?
Low density residential.
-8-
TO BE COMPLETED BY APPLICANT EVALZJATIONS FOR
AGENCY USE ONLY
g. If applicable, what is the.current shoreline master program
designation of the site? N/A
h. Bas any part of the site been classified as an "environ-
mentally sensitive" area? If so, specify.. No.
i. Approximately how many people would reside or work in the
completed project? Approximately 44 people (14 lots x 3.1
people /unit).
j. Approximately how many people would the canpleted project
displace? One family.
k. Proposed measures to avoid or reduce displacement impacts,
if any: None proposed.
1. Proposed measures to ensure the proposal is. compatible with
existing and projected lard uses and plans, if any: The propo-
sal is in conformance with the existing zoning and comprehen-
sive plan designations.
9. Sousing
a. Approximately how many units would be provided, if, any? In-
dicate whether high, middle, or low - income housing.
Fourteen middle income houses are proposed.
b. ' Approx imately how many units, if any, would be eliminated?
Indicate whether high, middle, or low- income housing.
One low income housing unit would be removed.
c. Proposed measures to reduce or control housing impacts, if
any: Refer to Land Use Response L. Observance of building set-
backs and height limitations and provision of additional land-
scaping, particularly in the perimeter areas, would ?urther re-
duce the housing impacts.
• •
TO. BE COMPLETED BY APPLICANT EUALLIATION FOR
AGENCY USE ONLY
10. Aesthetics
a. What is the tallest height of any proposed structure(s), not
including antennas; what is the principal exterior building
material(s) proposed /? The tallest height of any proposed struc-
ture is two stories. Woodsiding would be the principle exterior
building material.
b. What views in the immediate vicinity would be altered or ob-
structed? None.
c. Proposed measures to reduce or control aesthetic impacts, if
any: Refer to Housing Response C.
11. Light and Glare
a. What type of light or glare will the proposal produce. What
time of day would it mainly occur? The.proposal would produce light
from automobile headlights, street lighting and Fiome lighting pri-
marily at night.
b. Gould 1 ight or glare fran the finished proj ect be a . safety •
hazard or interfere with views? Not to our knowledge. Night light-
ing could actually promote project safety.
c. What existing off -site source of light or glare may affect your
proposal? Lights from adjacent residential developments and road-
ways could affect the proposal.
d. Proposed measures to reduce or control 1 ight and glare impacts,
if any: Units could be sited to avoid having lights from internal
and adjacent roadways and from surrounding development shine into
living areas.
12. Recreation
a. What designated and informal recreation opportunities are in
the inmed fate vicinity? Tukwila Park is located approximately two
blocks southeast of the,site. Fort Dent Park is northeast of the
site on the east bank of the Green River. School playfields are
located one block northwest of the site. City of Tukwila trail #4
passes adjacent to the site's western property line.
TO BE COMPLETED BY APPLICANT EVALUATION FOR
AGENCY USE ONLY
b. Hbuld the proposed project displace any existing re-
creational uses? If so, describe. The proposal would displace the
existing informal and illegal recreation associated with undevel-
oped lands.
c. Proposed measures to.reduce or control impacts on recreation,
• including recreation opportunities to be provided by the project
or appl icant , if any: None proposed.
13. Historic and Cultural Preservation
a. Are there any places or objects listed on, or proposed for na-
tional, state or local preservation registers known to be on Or
next to the site? If so, generally describe.
None to,our knowledge.
b. Generally describe any.landmarks or evidence of historic,
archaeological, scientific or cultural importance }mown to be on or
next to the site. None to our knowledge.
c. Proposed measures to reduce or control impacts, if any: N/A
14. Transportation
a. Identify public streets and highways serving the site and des-
cribe proposed access to the existing street system. Shaw on site
plans, if any. Access to the site would be from the north via S.
151st St., a collector arterial. No access to individual lots -
would be allowed from S. 151st St. or from 65th Ave. S.
b. Is the site currently served by public transit. If not, what is
the approximate distance to the nearest transit stop? Local public
transit runs on S. 151st St. and 65th Ave. S. Bxpress transit,
transfer points and park -and -rides are located to the south of ,the
site on Southcenter Blvd.
c. Fbw many parking spaces would the canpleted project have? How
many would the proj ect eliminate? Off - street parking would be ac-
commodated by driveways.
d. Will the proposal require any new roads or streets, or improve-
ments to existing roads or streets, not including driveways? If
sD, generally describe (indicate whether public or private) .
The proposal would require construction of approximately 550 lineal
feetof private roadway including two cul-d-sacs.
'10 BE COMPLETED BY APPLICANT EVALUATION FOR
AGENCY USE ONLY
e. Will the project use (or occur in the immediate vicinity of)
water, rail, or air transportation? If so, generally describe.
The project should not generate any extraordinary, use of water,
rail or air transportation.
f. Fbw many vehicular trips per day would be generated by the com-
pleted project? If known, indicate when peak volunes would occur.
Assuning 10 average daily trip ends, per the 1982 I.T.E. Trip Gen-
eration Report, the proposal would generate approximately 140 ADT.
Peak volumes would generally coincide with morning and evening com-
mute times.
g. Proposed measures to reduce or control transportation impacts,
if any: None proposed.
15. Public Services
a. Would the proj ect result in an increased need for public ser-
vice (for ecample: fire protection, police protection, health
care, schools, other)? If so, generally describe. The proposal
would place additional demands on existing public services.
b. Proposed measures to reduce or control direct impacts on pub-
lic services, if any. None proposed.
16. Utilities
a ..Cir-c- util ies c .ently-availab
natyral_aas water efuse serves
septic system, other.
b. Describe the utilities that are proposed for the project, the
utility providing the service, and the general construction
activities on the site or in the immediate vicinity which might be
needed. Refer to. preliminary plat map for a list of utility purvey-
ors. A11 utilities would be available to the proposal_ with the ex-
tension of existing lines.
C. SIGNATURE
The above answers are true and
ledge. I under stand that t
make its decisio%
• Signature : f`� G �;
Date Submitted •
oanplete to the bes -oir my know-
re ling than to
TO BE COMPLETED BY. APPLIT
E. SUPPLEMENTAL SHEET FOR ALL PROJECT AND NON PROJECT
PROPOSALS
The objectives and the alternative means of reaching the
objectives for a proposal will be helpful in reviewing the
aforegoing items of the Environmental Checklist. This
information provides a general overall perspective of the
proposed action in the context of the environmental infor-
mation provided and the submitted plans, documents, suppor-
tive information, studies, etc.
1. What are the objective(s) of the proposal? mn p rn vid e
single family detached hoiic n for the axes ac-
cording to the density and r,ther provisj.on6 al
lowed by the site's zoning and r,ompzehensive plan
designation.
Evaluation for
Agency Use Only
2. What are the alternative means of accomplishing these
objectives? Alternative means of accompliah-t.ng 11 -his
• objective could include development at nther rlPn'sities.
Higher density development would res1,ire rezone,
however.
3. Please compare the alternative means and indicate the
preferred course of action: The prnpnsa 1 is tho pro -
ferred course of action since it is not in conflict
with the existing zoning, comprehensiue plan desig-
nation and land use in the area
.11: EWE
JUN 13 1986
GITY OF TU$ WiLA
PLANNING DEPT.
Evaluation for
Agency Use Only
4. Does the proposal conflict with policies of the Tukwila
Comprehensive Land Use Policy Plan? If so, what poli-
cies of the Plan? No.
Proposed measures to avoid or reduce the conflict(s)
are: None proposed.
-23-
RECENED
CRY OF =M8,
JAN 161986
moan DEGI6):
GEOTECHNICAL ENGINEERING STUDY
SCHNEIDER HOMES, INC.
MAPLETREE VILLAGE
TUKWILA, WASHINGTON
E -2739
FOR
SCHNEIDER HOMES, INC.
Earth
Consultants Inc.
Professional Personnel
Schneider Homes, Inc.
c/o Group Four, Inc.
19502 -56th Avenue West
Lynnwood, Washington 98036
Attention: Mr. Jim Egge
Gentlemen:
January 8, 1986
E -2739
We are pleased to submit herewith our report entitled "Geotech-
nical Engineering Study, Schneider Homes, Inc., Mapletree Village,
Tukwila, Washington. ". This report presents the results of our
field exploration, laboratory tests, analysis and engineering
judgement. The purpose and scope of our study was outlined in our
proposal dated September 5, 1985.
This report has been prepared for specific application to this
project in accordance with generally accepted geotechnical
engineering practices for the exclusive use of Schneider Homes,
Inc. and their representatives. No other warranty, expressed or
implied, is made. We recommend that this report, in its entirety,
be included in the project contract documents for the information
of the contractor. The following sections of this report describe
our study and contain recommendations regarding foundation design
criteria, earthwork considerations, and site drainage.
PROJECT DESCRIPTION
At the time our study was performed, the site and proposed
building locations were as shown schematically on the Test Pit
Location Plan, Plate 2.
Based on discussions with you, and details shown on the Site
Development Plan and Grading Plan prepared by Group Four, Inc., we
understand that twenty three (23) one or two story buildings
containing seventy (70) single - family housing units will be
constructed. Access to the development will be provided by
construction of South 152nd Street and 64th Avenue South.
Schneider Homes, Inc.
January 8, 1986
E-2739
Page 2
If any of the above development criteria change, we should be
'consulted to review the recommendations contained in this report.
In any case, it is recommended that Earth Consultants, Inc. (ECI)
provide a general review of the final design.
SITE CONDITIONS
Surface
The approximately ten acre site is located north of the
Southcenter Shopping Mall at the southwestern intersection of 65th
Avenue South and South 151st Street in Tukwila, Washington. Two
structures exist on the otherwise wooded hilltop site. The
northeast structure is presently occupied where as the structure
located in the southeastern corner is abandoned.
The site is characterized by relatively high ground in the
north, central and eastern portions and low wet boggy ground in
the west and southern areas. Surface water drainage from adjacent
high areas to the north enters the site near the northwestern
corner, creating a seasonal stream with associated ponding
throughout the low ground of the western portion of the site.
This stream flow exits the site near the southwestern corner via a
culvert. The southern low ground apparently collects only surface
runoff from the site. This area drains slowly through a swale
extending to the south between existing residences.
The high ground is dominated by three rock knobs or peaks
about twenty (20) feet in height that extend across the property
center from northwest to southeast. The remainder of the high
ground is flat lying to gently sloping.
The northcentral part of the site has been cleared of trees
and now has a secondary growth of blackberry brush, grasses and
weeds. The remainder of the site is covered with trees consisting
of alder, maple, fir and cedar. Low areas contain abundant
willow, alder, vine maple and cottonwood trees. Marsh areas have
a growth of buttercup, reeds and skunk cabbage.
Subsurface
The site was explored by excavating twelve (12,) test pits and
a trench at the locations shown on Plate 2. Logs of the test
pits, Plates 4 through 11, present a detailed description of the
conditions encountered at each location explored. A description
of the field exploration methods and laboratory testing program is
included in this report following the Discussion and
Recommendations section. Following is a generalized description
of the subsurface conditions encountered.
Earth Consultants, Inc.
Schneider Homes, Inc.
January 8, 1986
E -2739
Page 3
Soils at the site consist of highly weathered bedrock under-
lying the upland area and thick accumulations of peat, alluvial
clays, silts and sands underlying the low ground. In general, two
different types of rock formation were encountered on the site.
The most prevalent rock type encountered on the site is
sedimentary in origin. It is weak to moderately cemented and
highly weathered to approximately ten feet in depth. Grain sizes
range from siltstone and fine sandstone in the northern part of
the site, as demonstrated by Test Pits TP -1, TP -2, TP -3 and TP -11,
to coarse sandstones and boulder conglomerates found in Test Pits
TP -6, TP -7, TP -10 and TP -12. In the coarser materials many of the
pebbles were entirely weathered to soil and even the boulders had
numerous concentric weathering rinds. Within the weathered fine
fraction only a brown unit color and some iron staining on bedding
planes and joints were observed. These types of bedrock are
comparable to the glacially consolidated soils of the region.
The second rock type is of igneous origin and is described as
a porphyritic andesite. It was encountered in Test Pits TP -4 and
TP -5 and the test trench. Surficial exposure of the andesite
corresponds with the hill peaks and trends west by northwest
across the site. Test pit and trench observations indicate a
layer of approximately thirty five (35) to forty (40) feet in
thickness, tilted toward the southwest at approximately 30 to 35
degrees from the horizontal. Weathering in this unit is highly
irregular and is dependent on the joint or fracture density.
The two marshy areas adjacent to the western and southern
property boundaries contain peat and soft organic soils to depths
of twelve (12) feet or more. Underlying the organic soils are
saturated silty sand and gravel layers as encountered in Test Pits
TP -8 and TP -9.
Groundwater
Groundwater seepage levels observed while excavating are shown
on the test pit logs. The groundwater level is not static, thus
one may expect fluctuations in the level depending on the amount
of rainfall, surface water runoff, and other factors. Generally
the water level is higher in the wetter winter months.
Some seepage may be expected into excavations in permeable
soil layers, especially during wet weather.
DISCUSSION'AND RECOMMENDATIONS
General
A site development diagram and grading plan were received, on
November 6, 1985. These documents indicate a multi - family
Earth Consultants, Inc.
Schneider Homes, Inc.
January 8, 1986
E -2739
Page 4
development comprised of seventy (70) units in groups of two to
four units. In general, units located at the western (Units 1
through 18) and southern (Units 19 through 34) margin of the
development will be located primarily on fills extending over
existing peat deposits. Based on the proposed finished floor
elevations, fill will vary from five (5) to twenty eight (28) feet
in depth. Exceptions to these generalizations occur at Units 1
and 2 with four feet of cut (4'C) and one foot of fill (1'F),
Units 9 through 11 with 17'C and 28'F, Units 31 and 32 with 8'C
and 5'F and Units 33 and 34 with 10'C and 0'F.
Similarly, units located near the interior, northern and
eastern margin of the development will be founded primarily on cut
sections up to thirty (30) feet in depth. Exceptions occur at
Units 35 and 36 (23'C, 5'F), Units 45 through 47 (2'C, 11'F) and
Units 48 through 50 (7'C, 13'F). In addition, most of the planned
roadways will be located in cuts up to twenty six (26) feet in
depth. Cut excavations will occur for the most part in soil
materials or relatively soft, weakly cemented sedimentary rock).
The soil and soft rock are expected to be rippable and normally
excavated using customary equipment and techniques. .Excavations
in the vicinity of the three rock peaks, trending west by
northwest across the site, will occur in hard igneous rock
described as a porphyritic adesite. ECI's interim report, dated
October 7, 1985, expressed the belief that the upper fifteen (15.)
to twenty (20) feet of andesite would be rippable with heavy
equipment on a relatively large working face. Depending upon the
tightness and spacing of joints in the hard rock mass, excavations
below fifteen (15) feet or on small working faces, such as utility
trenches, may encounter difficulty. Based on the grading plan,
hard andesite excavations are expected for site grading,
foundations, buried utilities and access roadways at Units 37
through 42, 52 and 53. A potential for similar hard rock
conditions also exists for Units 9, 10, 11, 35, 36, 43, 44 and 51.
The low marshy areas adjacent to the west and south property
boundaries will be partially covered by fill supporting housing
units and the South 152nd Street roadway. Peat and soft organic
soil deposits in these areas will be subject to vertical and
lateral displacements as a result of loads imposed by the fill.
ECI's interim report suggested three potential procedures for the
placement of the required fill materials. The first and most
positive .procedure would entail the removal of all soft organic
deposits prior to the placement of any overlying fill. Based on
the proposed grading plan and assuming a maximum depth of twelve
(12) feet, we estimate that approximately 34,000 cubic yards of
material would be removed and replaced by this option.
Excessive settlements in the compressible soils _can be reduced
by pre- loading the marshy areas with fill material. Fill would be
Earth Consultants, Inc.
Schneider Homes, Inc.
January 8, 1986
E -2739
Page 5
placed to a height of three to four feet above planned finished
grade elevation and allowed to settle for a period presently
estimated to be from two to three months. Actual settlement times
would be determined by monitoring the rate and magnitude of
movements. Maximum settlement for twelve (12) feet of organic
soils under the maximum fill depth of twenty six (26) feet is .
estimated to be on the order of four feet. Erection of any
structures, roadways or buried utilities would be delayed until
the risk of substantial damage has been reduced to limits
acceptable by the owner. The pre - loading scheme has been widely
used for similar deposits in the Puget Sound area but does carry a
greater degree of risk than "removal of the organic soils.
A third alternative for treatment of the soft organics is
based on their displacement by a mud -wave action during the
placement of fill. This procedure requires that the materials
being displaced experience shear failure due to loading imposed by
the new fill. The leading edge of fill is advanced as the soft
soils fail and are laterally displaced. Our general experience
indicates that fill heights of ten (10) to fifteen (15) feet may
be necessary to initiate and maintain the failure mechanism. The
success of this technique is largely dependent upon the
composition and texture of the materials being displaced. In
peaty and organic soils, both characteristics will vary widely
throughout the deposits and as a result, the mud -wave technique
must be planned in association with and closely monitored by an
experienced geotechnical engineer. Provisions should be readily
available for modifications to the procedure based on the observed
performance. The major risks of this procedure occur from
entrapment of compressible soil pockets within the fill and the
uncertainty of complete ,,displacement below the fill.
Theoretically, the quantity of displaced and fill materials should
be nearly equal to the removal procedure quantities. The fill
should be monitored for several weeks after completion before
structures or facilities are erected.
Site Preparation and General Earthwork
The building and pavement areas should be stripped and cleaned
of all slabs, trees, existing utilities, debris and any other
deleterious material. In general, a stripping depth from six (6)
to twenty four (24) inches will be required except in rock and
marsh areas. Stripped materials should be removed from the site
or stockpiled for later use in landscaping, if desired. The
stripped materials should not be mixed with any materials to be
used as structural fill. Structural fill is defined as any fill
material placed under buildings, roadways, slabs, pavements, or
any other load bearing areas.
Earth Consultants, Inc.
Schneider Homes, Inc.
January 8, 1986
E -2739
Page 6
Following the stripping operation, the exposed ground surface
should be proofrolled. All proofrolling should be performed under
the observation of a representative of ECI. Soil in any loose or
soft areas should be removed and replaced with structural fill to
a depth that will provide a stable base for overlying fill or
structures.
Hill side slopes steeper than 4:1 (Horizontal:Vertical) should
be properly benched prior to the placement of any overlying fill
material. The vertical depth of benching should be equal to or
greater than the compacted thickness of the fill lift or layer.
The horizontal bench surface should have an outward slope of less
than 5 percent. A 6:1 (H:V) transition from cut to fill section
should be provided for the upper twelve (12) inches of fill
supporting structures or roadways and in buried utility trenches.
All fill materials should be placed in horizontal lifts or
layers not exceeding twelve (12) inches in compacted thickness
unless adequate compactive effort for thicker lifts can be
demonstrated to the satisfaction of the geotechnical engineer.
Fill lifts less than twelve (12) inches may be necessary to
achieve the required compaction density. The moisture content of
fill materials should not vary more than 5 percentage points from
the optimum moisture content determined by the' laboratory
compaction test standard.
Structural fill under floor slabs and footings should be
compacted to a minimum density equal to or: greater than 95 percent
of the maximum dry density determined in-accordance with ASTM Test
Designation D -1557 (Modified Proctor). Fill under pavements and
walks should be compacted to 90 percent of the maximum density
except for the top twelve (12) inches which should be compacted to
95 percent of the maximum density.
At the time of our exploration, the moisture content of
on -site soils was near the optimum moisture content and could be
used as structural fill provided that grading operations are
conducted during relatively dry weather.. However, the on -site
soils contain a significant amount of fine material smaller than
the No. 200 sieve size and thus, are moisture sensitive.
Compaction and grading operations will be difficult if the soil
moisture exceeds the optimum moisture content. Therefore, unless
the moisture content can be controlled, it may be necessary to
import granular soil for structural fill. Natural moisture
contents can be reduced by aeration in dry weather and by using
lime or cement stabilization. Ideally, structural fill which is
to be . placed in wet weather should consist of a granular material
with a maximum particle size of three inches and no more than 5
percent fine material passing the No. 200 sieve.
Earth Consultants, Inc.
Schneider Homes, Inc..
January 8, 1986
Foundations
E -2739
Page 7
The proposed structures may be supported on conventional conti-
nuous and spread footings 'bearing on at least one foot of
structural fill or recompacted native soil. Overexcavation of
soil and rock in cut sections below the footings should be
required to decrease the magnitude of differential settlements.
Fill placed under footings should extend outwards from the edge of
the footings on a 1:2 (H:V) slope. Exterior footings should be
bottomed at a minimum depth of eighteen (18) inches below the
lowest adjacent outside finish grade. Interior footings may be at
a depth of twelve (12) inches below the top of the slab. Footings
bearing on structural fill as recommended may be designed for a
bearing pressure of twenty five hundred (2500) pounds per square
foot (psf). Continuous and individual spread footings should have
minimum widths of twelve (12) and eighteen (18) inches,
respectively. A one -third increase in the above bearing pressures
may be used when considering short term wind or seismic loads.
Excluding the effects of soft organic deposits below the fill,
it is anticipated that total settlements of footings founded on a
maximum of twenty eight (28) feet of fill will be about 2.7
inches. Footings founded within twelve (12) inches of the rock
surface will demonstrate negligible settlements. Therefore, .
maximum differential settlements on the order of two and one -half
inches may be possible. Continuous footings located in cut -fill
transition zones should be considered for additional reinforcement
to reduce the possibility of structural damage due to differential
settlement.
Lateral loads due to wind or seismic forces may be resisted by
friction between the foundations and the supporting compacted fill
subgrade or by passive earth pressure on the foundations. For the
latter, the foundations must be poured "neat" against the existing
soil or backfilled with a compacted fill meeting the requirements
of .structural fill. A frictional coefficient of 0.35 may be used
between the structural foundation concrete and the supporting
subgrade. The passive resistance of undisturbed natural soils and
well compacted fill may be taken as equal to the pressure of a
fluid having a density of three hundred fifty (350) pounds per
cubic foot (pcf).
We recommend that drains be placed around all perimeter foot-
ings. The drains should be constructed with a four inch diameter
perforated pipe bedded and covered with free draining gravel. The
drains should have a positive gradient towards suitable discharge
facilities. The footing drainage system should not be tied into
the roof drainage system until the drains are tightlined well away
from the building. The footing excavation should be backfilled
with granular soil except for the top foot which should be
backfilled with a relatively impermeable soil such as silt, clay
Earth Consultants, Inc.
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January 8, 1986
E -2739
Page 8
or topsoil. Alternatively, the surface can be sealed with asphalt
or concrete pavements.
Slab -on -Grade Floors
Slab -on -grade floors may be supported on the compacted
structural fill.' Disturbed native soils should be recompacted or
replaced with structural fill. A subgrade reaction modulus of two
hundred (200) pounds per cubic inch may be used for slabs bearing
on the specified structural fill. The slab should be provided
with a minimum of four inches of free draining sand or gravel as a
capillary barrier. We also recommend that a vapor barrier, such
as 6 mil plastic membrane, be placed beneath the slab to reduce
water vapor transmission through the slab and the resultant
moisture accumulation. Two inches of sand may be placed over the
membrane for protection during construction and to aid in curing
of the concrete.
Retaining and Foundation Walls
Retaining and foundation walls should be designed to resist
lateral earth pressures- imposed by the soils retained by these
structures. Walls that are designed to yield an amount equal to
at least 0.002 times the wall height can be designed to resist the
lateral earth pressure imposed by an equivalent fluid with a unit
weight of forty (40) pcf. If walls are to be restrained at the
top from free movement, a uniform force of one hundred (100) psf
should be added to the equivalent fluid pressure force. For
calculating the base resistance to sliding, we recommend using a
passive pressure equivalent to that exerted by a fluid having a
density of three hundred fifty (350) pcf and a coefficient of 0.35
for frictional resistance.
The wall pressures apply only for a maximum wall height of ten
feet. It is assumed that no hydrostatic pressures act behind the
wall and that no surcharge slopes or loads will be placed above
the walls. If surcharges are to be applied they should be added
to the above lateral pressures.
Retaining and foundation walls should be backfilled with
compacted free - draining granular soils. The wall backfill should
contain no more than 5 percent silt or clay sized particles and no
particles greater than four inches in diameter. The percentage of
particles passing the No. 4 sieve should be between 25 and 70
percent. Alternatively, a geotextile drainage product such as
Miradrain may be used. We recommend the use of footing drains at
the base of all retaining wall footings. The footing drains
should be surrounded by at least six inches of one inch minus
washed rock, and provided with a positive gradient towards
suitable discharge facilities. The pipe invert should be at least
Earth Consultants, Inc.
Schneider Homes, Inc.
January 8, 1986
E -2739
Page 9
as low as the bottom of the footing. For retaining walls, other
than basement walls, weepholes can be used. The weepholes should
be as low as possible to maintain drainage behind the walls. When
weepholes are provided, all backfill within eighteen (18) inches
of the weephole should consist of one inch minus washed rock.
Excavations and Slopes
In no case should excavation slopes be steeper or higher than
the limits specified in local, state and national government
safety regulations. Temporary cuts greater than five feet in
height should have an inclination no steeper than 1.5:1 (H:V). As
an alternate to .open cuts, temporary shoring can be used in
conjunction with vertical cuts. Detailed criteria for shoring
systems can be developed later, if needed.
All permanent cut and fill slopes should be inclined no
steeper than 2:1 (H:V). These recommendations are applicable to
slopes with a maximum height of thirty (30) feet. If higher
slopes are anticipated, ECI should be contacted to review the
design and construction criteria. It is also recommend that ECI
examine all excavated slopes to evaluate actual exposed
conditions. Supplementary recommendations can be developed, if
needed, to improve stability, including flattening of slopes or
installation of surface or subsurface drains. In any case, water
should not be allowed to flow uncontrolled over the top or down
the face of any slopes.
All permanently exposed slopes should be seeded with an
appropriate species of vegetation to reduce erosion and improve
stability of the surficial layer of soil.
Site Drainage
Groundwater was encountered only in test pits excavated in low
areas of the site. However, it has been our experience that
groundwater levels can change significantly due to changes in
precipitation, surface drainage alteration or other factors. If
seepage is encountered in any excavation, the water should be
drained away from the site by the use of ditches, perforated pipe,
or by pumping from sumps at the low point of the excavation.
Appropriate locations for subsurface drains, if needed, can be
established during grading operations by a representative of ECI,
at which time the seepage areas, if present, may be more clearly
defined.
The site surface and all excavations should be graded so that
surface water is directed off the site and away from the tops of
slopes. Water should not be allowed to stand in any area where
Earth Consultants, Inc.
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January 8, 1986
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Page 10
buildings, slabs, or pavements are to be constructed. During
construction, loose surfaces should be sealed at night by
compacting the surface soils to reduce infiltration rates. Final
site grades should allow for drainage away from the building
foundations. We suggest that the ground be sloped 3 percent for a
distance of at least ten feet away from the buildings except in
areas that are to be paved.
Pavement Areas
All parking and roadway areas may be supported on native soils
or existing fills provided these soils can be compacted to 95
percent of maximum density and are stable at the time of construc-
tion. Additional structural fill and /or geotextile fabric may be
needed to stabilize soft, wet or unstable areas. In most
instances twelve (12) inches of granular fill will stabilize the
subgrade except for very soft areas where additional fill could be
required. The upper twelve (12) inches. of pavement subgrade
should be compacted to at least 95 percent of the maximum density.
Below this level a compactive effort of 90 percent will be
adequate. The minimum pavement section for lightly loaded traffic
and parking areas should consist of three inches of asphalt
concrete (AC) over four inches of crushed rock base (CRB) or three
inches of asphalt treated base (ATB). Heavier loaded areas may
require thicker sections. ECI will be pleased to assist you in
developing appropriate pavement sections or specifications for
heavy traffic zones, if needed.
FIELD EXPLORATION AND LABORATORY TESTING
Our field exploration was performed on September 11, 13, 16,
and 24, 1985. The subsurface conditions were explored by
excavating twelve (12) test pits to a maximum depth of sixteen
(16) feet below the existing surface at the approximate locations
shown on Plate 2.
The locations of the test pits were approximately determined
by measurement from survey located features. Elevations of test
pits were approximately determined by comparison with contour map.
The locations and elevations of the test pits should be considered
accurate only to the degree implied by the method used.
The field exploration was continuously monitored by an engi-
neering geologist from our firm who classified the soils
encountered, maintained a log of each test pit, obtained
representative bulk soil samples and observed pertinent site
features. Soils were classified visually in the field according
to the Unified Soil Classification System which is presented on
Plate 3, Legend. The consistency of the soil was estimated based
on torvane and penetrometer tests, the effort required to excavate
Earth Consultants, Inc.
Schneider Homes, Inc.
January 8, 1986
E -2739
Page 11
the soil, the stability of the trench walls and other factors.
Logs of the individual test pits are presented on Plates 4 through
11, Test Pit Logs. The final logs represent our interpretations
of the field logs and the results of the laboratory examination
and test of field samples. The stratification lines on the logs
represent the approximate boundary between soil types. In
actuality, the transition may be gradual.
Representative soil samples were placed in closed containers
and returned to our laboratory for further examination and test-
ing. Visual classifications were supplemented by index tests such
as Atterberg Limits on representative samples.
LIMITATIONS
Our recommendations and conclusions are based on the site
materials observed, selective laboratory testing, analyses and
engineering judgement. The conclusions and recommendations are
professional opinions derived in accordance with current standards
of practice. No warranty is expressed or implied.
The recommendations submitted in this report are based upon
the data obtained from the test pits. Soil and groundwater
conditions between test pits may vary from those encountered by
the test pits. The .nature and extent of variations between test
pits may not become evident until construction. If variations
then appear, ECI should be allowed to reevaluate the recommenda-
tions of this report prior to proceeding with the construction.
Additional Services
It is recommended that ECI provide a general review of the
final design and specifications to verify that the earthwork and
foundation recommendations have been properly interpreted and
implemented in the design and in the construction specifications.
It is also recommended that Earth Consultants, Inc. be
retained to provide geotechnical services during construction.
Because of the nature of this project and the the soil conditions,
ECI does not accept responsibility for the performance of the
foundation or earthwork unless we are retained to review the
construction drawings and specifications, and to provide
construction observation and testing services. This is to observe
compliance with the design concepts, specifications or rec-
ommendations and to allow design changes in the event subsurface
conditions differ from those anticipated prior to the start of con-
struction.
Earth Consultants, Inc.
Schneider Homes, Inc.
January 8, 1986
E -2739
Page 12
The following plates . are attached and complete this report:
Plate 1 Vicinity Map
Plate 2 Test Pit Location Plan
Plate 3 Legend
Plates 4 through 11 Test Pit Logs
Plate 12 Atterberg Limits
Respectfully submitted,
LTANTS, INC.
oran, P.E.
Project - . -- ager
` `.
14691 �, _ .: a Ro• S. Levinson, P. E.
/S� "��i " 11 President
ilfe
JJM /RSL /tm = s, ONAL lit •
cc: Schneider Homes, Inc.
Attn:. Gerald Schneider
Earth Consultants, Inc.
Reference :
King County / Mop 41
By Thomas Brothers Maps
Doted 1986
Earth
Consultants
GEOTECHNICAL ENGINEERING &GEOLOGY
Vicinity ; Map
Proposed Multi Family Residences
Tukwila, Washington
Proj. No. 2739 1Date Nov '85
Plate
151 st STREET
Approximate Scale
40 80 160ft.
Proposed Building
Reference :
Site Plan
By Group Four, Inc.
Undated
145 (50 150
60 155 150 145
GEOTECHNICAL ENGINEERING b GEOLOGY
Test Pit Location Plan
Proposed Multi Family Residences
Tukwila, Washington
Proj. No. 2739 Date Nov. '85 Plate
MAJOR • DIVISIONS
GRAPH
SYMBOL
LETTER
SYMBOL
TYPICAL. DESCRIPTION
Coarse
Grained
Soils
•
More Than
50% Material
Larger Than
No. 200 Sieve
Size
Gravel
And
Gravelly
Soils
More Than
50% Coarse
Fraction
Retained On
No. 4 Sieve
Clean Gravels
(little or no fines)
�;° •4,° •o •°
`'.09 p'e e°e.e°
--
GW
9W
Well- Graded Gravels, Gravel -Sand
Mixtures, Little Or No Fines
• •x::0::0::
• • �• ' • • •
GP
gp
Poorly - Graded Gravels, Gravel-
Sand Mixtures, Little Or No Fines
Gravels With
Fines ( appreciable
amount of fines)
GM
gm
Silty Gravels, Gravel -Sand-
Silt Mixtures
0
GC
Clayey Gravels, Gravel- Sand -
Clay Mixtures
Sand
And
Sandy
Soils
More Than •
50% Coarse
Fraction
Passing No.4
Sieve
Clean Sand
(little or no fines)
0 **0°0•3:.°:
o 0° o
:0:: 0 0
SW
SW
Well- Graded Sands, Gravelly
Sands, Little Or No Fines
,• ... . Q �•t.
:. ;;:• •
••' ••
♦'•�•••�••�-
SP
Sp
Poorly- Graded Sands, Gravelly
Sands, Little Or No Fines
Sands With
Fines (appreciable
amount of fines)
SM
Sm
Silty Sands, Sand - Silt Mixtures
y ��'
�J>
,'
SC
SC
Clayey Sands, Sand Clay Mixtures
Fine
Grained
Soils
More Than
50% Material
Smaller Than
No. 200 Sieve
Size
Silts Liquid Limit
And • Less Than 50
Clays
ML
ml
Inorganic Silts & Very Fine Sands, Rock Flour,Silty-
Clayey Fine Sands; Clayey Silts w/ Slight Plasticity
%��
CL
CI
Inorganic Clays Of Low To Medium Plasticity,
Gravelly Clays, Sandy Clays, Silty Clays, Lean
I �
I I I
I I
I
OL
OI
Organic Silts And Organic
Silty Clays Of Low Plasticity
Silts Liquid Limit
And Greater Than 50
Clays
I
MH
mh
Inorganic Silts, Micaceous Or Diatomaceous Fine
Sand Or Silty Soils
-
CH •
Ch
Inorganic Clays Of High
Plasticity, Fat Clays.
f /////
OH
Oh
Organic Clays Of Medium To High
Plasticity, Organic Silts .
Highly Organic Soils
..� s
pT
pt
Peat, Humus, Swamp Soils
With High Organic Contents
Topsoil
..,..
Humus And Duff Layer
Fill
►••••�•�•••••• •
Highly Variable Constituents
The Discussion In The Text 01 This Report Is Necessary For A Proper Understanding
Of The Nature 01 The Material Presented In The Attached Logs
Notes :
Dual symbols are used to indicate borderline soil classification. Upper
case letter symbols designate sample classifications based upon lab -.
oratory testing; lower case letter symbols designate classifications not
verified by laboratory testing.
I 2 "0.D. SPLIT SPOON SAMPLER
2.4" I.D. RING SAMPLER OR
II SHELBY TUBE SAMPLER
P SAMPLER PUSHED
4- SAMPLE NOT RECOVERED
2 WATER LEVEL (DATE)
aWATER OBSERVATION WELL
C TORVANE READING, tsf
qu PENETROMETER READING, tsf
W MOISTURE, percent of dry weight
pcf DRY DENSITY. pounds per cubic ft.
LL LIQUID LIMIT, percent
PI PLASTIC INDEX
Earth ;OA
Consultants Inc.
GEOTECHNICAL ENGINEERING & GEOLOGY
LEGEND
Proj. No. 2739 ID8sept.t85 I 3
Depth
(ft.)
0
5
10
15
Logged By. FC
Date 9/11/85
USCS
TEST PIT
Soil Description
Elev..1nn±
W
1961
Earth 414)
Consultants Inc.
•GEOTECNNICAL ENGINEERING & GEOLOGY
TEST PIT LOGS
PROPOSED MULTI FAMILY RESIDENCE
TUKWILA, WASHINGTON
Proj. Na. 2739 1 Date Sept. '85
Plate 4
-
Depth
(ft.)
0
10
Logged By FC
Dais 9/11/85
USCS
TEST PIT
Soil Description
Elev. 1701
15 F�
20
Tan silty organic TOPSOIL
r
Tan to mottled orange sandy SILT in layers,
plastic, moist, soft
Tan sandy SILTSTONE, occasional coal fragments,
highly weathered, closely jointed with black
stains on joint faces
Test pit terminated at 16 feet below existing grade. No ground-
water seepage encounted during excavation.
GEOTECHNICAL ENGINEERING & GEOLOGY
TEST PIT LOGS
PROPOSED,MULTI FAMILY RESIDENCE
TUKWILA, WASHINGTON
Proj. No. 2739 ' Date Sept. ' 85 IPhde 5
Logged ®y' FC
Date 9/11/85
Depth
(ft.) USCS
0
5
10
15
TEST PIT NO.
Elev. 172±
Soil Description
GEOTECHNICAL ENGINEERING & GEOLOGY
TEST PIT LOGS
PROPOSED MULTI FAMILY RESIDENCE
TUKWILA_, WASHINGTON
Proj. No.2739
Date Sept : ' 85 Fats 6
Tan silty organic TOPSOIL �-
1-
iml
sm
Tan silty SAND to sandy-SILT with gravel and
occasional boulders, moist, dense, (highly
weathered mudstone)
Tan °to gray.SILTSTONE, thin beddled, occasional
fossil clam or organic fragments, moderate to`"
little weathered, closely fractured with no..
stains on joints below 9 feet
: - -_'
i
Test Pit terminated at 15 feet below existing grade. No ground-
water seepage encountered during excavation.
•
GEOTECHNICAL ENGINEERING & GEOLOGY
TEST PIT LOGS
PROPOSED MULTI FAMILY RESIDENCE
TUKWILA_, WASHINGTON
Proj. No.2739
Date Sept : ' 85 Fats 6
Depth
(ft.)
o
5
10
15
0
5
10
15
Logged By FC
Date
9/11/85
USCS
TEST PIT NO.
Soil Description
Elev. 1851
W
(96)
TOPSOIL
Tan to gray ANDESITE, porphyritic, deeply
weathered, closely fractured with a spacing
of 1" to 6" to total penetration of brown stain
on joint faces
r
Test Pit terminated at 5 feet below existing grade. No groundwater
-:seepage encountered during excavation.
Logged By FC
Date 9/11/85
TEST PIT NO.��
E lev. 1951
Thin tan TOPSOIL
-Tan to orange ANDESITE, porphyritic, deeply
weathered, spheroidal into boulders and sandy
SILT, closely jointed with deep stain penetration,
less weathering below 4 feet
Test Pit terminated at 5 feet below existing grade. No groundwater
seepage encountered during excavation.
MIN
Earth '00
Consultants Inc.
•GEOTECHNICAL ENGINEERING & GEOLOGY
TEST PIT LOGS
PROPOSED MULTI FAMILY RESIDENCE
TUKWILA, WASHINGTON
Proj. No. 2739
Date Sept. ' 85
Plate 7
Depth
(ft.1
0
10
15
5
10
15
•
Logged By FC
Date 9/13/85
USCS
TEST PIT
Soil Description
EIev. 165±
W
(%)
Thin TOPSOIL layer
Tan silty SAND with gravel bedded fine to medium
sand, fine gravel with occasional cobbles dry
to slightly moist, dense, highly weathered
sandstone
Alternating layers of small gravel conglomerate
and fine to .medium grained sandstone, all very
highly weathered, some pebbles reduced to iron
oxide below 5 feet
Test Pit terminated at 13 feet below existing grade. No ground -
waterHseepage encountered during excavation.
Logged By FC
Date 9/13/85
TEST PIT
Elev. . 145±
Earth 41010;11/
Consultants Inc.
•,GEOTECHNICAL ENGINEERING & GEOLOGY
TEST PIT LOGS - .
PROPOSED MULTI FAMILY RESIDENCE
TUKWILA, WASHINGTON
Proj. No. 2739 IDatesept.'85 -Plate 8
Brown silty organic TOPSOIL
r
1
ml
Tan to mottled orange SILT, plastic, contains
some -gravel, wet, stiff
—,,•,,
Gp
Tan to gray sandy gravel containing boulders
'i"
and clay, fine to coarse sands,. boulders to 2',
.
wet, very dense
.4—
* •
.4
V
.
`.'TestiPit terminated at 8 feet below existing grade. Minor ground-
-
: water water encountered at 6 feet during excavation.
—
; I
Earth 41010;11/
Consultants Inc.
•,GEOTECHNICAL ENGINEERING & GEOLOGY
TEST PIT LOGS - .
PROPOSED MULTI FAMILY RESIDENCE
TUKWILA, WASHINGTON
Proj. No. 2739 IDatesept.'85 -Plate 8
Depth
(ft.)
0
5
10
15
10
15
Logged By FC
Date 9/13/85
USCS
TEST PIT
Soil Description
Elev. 142±
W
(96)
..77e7,..4
-
- - w
■
�.
pt
Brown PEAT, slightly fibrous, wet, soft.
Ash layer at 1'
-j
r.
•••
.�.
i:s��
sm
-.
-
J
"1
.•
sp
Gray SAND, thin bedded fine to medium grained
sand with occasional'thin layers of silt,
saturated, loose
_
';Test Pit terminated at 13 feet below existing grade.
seepage encountered at 8 feet during excavation.
A.
Groundwater,
Logged By FC
Date 9/13/85
TEST PIT NO. g
Elev. 142±
�-`_
-r-:-..t7
k
0.._
�"
"' -'-
M._
-7
, pt
Brown PEAT, slightly fibrous, contains abundant
fine gravel, wet, soft
Ash layer at 1'
-j
r.
•••
.�.
i:s��
sm
-.
Gray silty SAND with gravel, fine to medium
sand, fine to coarse gravel, occasional cobbles,
wet, medium dense
becomes dense to very dense at 12 feet
r
'iTest'Pit terminated at 13 feet below existing grade. Minor
groundwater seepage encountered at 12 feet during excavation.
•GEOTECHNICAL ENGINEERING .A GEOLOGY
TEST PIT LOGS
PROPOSED MULTI FAMILY RESIDENCE
TUKWILA, WASHINGTON
Proj. No. 2739
Date Sept. '85
Plate 9
Depth
(ft.)
0
10
15
Legged By FC
Date 9/13/85
USCS
TEST PIT NO. Al2...
Soil bescription
Elev. ...120±
(%)
Tari silty organic TOPSOIL
sm
Tan silty SAND with gravel, bedded, fine.to
Coarse sand, fine gravel, occasional cobbles,
dry to slightly moist, very dense
(highly weathered conglomeritic. sandstone)
becomes moist at 11 feet
coarser gravel below 13'
1
Test Pit terminated at 14 feet below existing grade. No ground-
water seepage encountered .during excavation.
Earth
Consultants Inc.
GEOTECHNICAL ENGINEERING & GEOLOGY
TEST PIT LOGS
PROPOSED MULTI FAMILY RESIDENCE
TUKWILA, WASHINGTON
Proj. No. 2739 1 Date Sept. '85 'Plate 10
By — C
Date 9/24/85
Depth .
(ft.)
5
10
15
0
5
10
15
USCS
TEST PIT NO. 11
Soil Description
EIev.
W
(%)
Dark brown organicTOPSOIL
ch
Tan to gray sandy CLAY, plastic, wet, stiff
becoming dense
ONO
SIM
Test'Pit terminated at 4 feet below existing grade. No groundwater
seepage encountered during excavation.
Logged By FC
Date 9/24/85
TEST PIT NO. 12
EIev. 165±
Earth 0/
Consultants hoc.
•GEOTECHNICAL ENGINEERING & GEOLOGY .
TEST PIT LOGS
PROPOSED MULTI FAMILY RESIDENCE
TUKWILA, WASHINGTON
Proj. No. 2739 . I Date Sept.85 Plate 11
«1
Tan silty organic TOPSOIL
f
:'''"
.,:
_c
:
•
•
•
.
sm
Tan to orange silty SAND with gravel and
occasional cobbles, dry to moise, dense to very
dense
Few rounded boulders at 4 feet
—
Test Pit terminated at 9 feet below existing grade. No ground
water seepage encountered during excavation.
Earth 0/
Consultants hoc.
•GEOTECHNICAL ENGINEERING & GEOLOGY .
TEST PIT LOGS
PROPOSED MULTI FAMILY RESIDENCE
TUKWILA, WASHINGTON
Proj. No. 2739 . I Date Sept.85 Plate 11
I00
x 60
W
G
Z
E
1- 40
`—A -Line
CL-ML
g)®
,0
20
40
LIQUID UMIT
80
Key
Boring/
lest Pit
Depth
(ft)
Soil Classification
USCS
L.L.
P.L..
P1.
Natural
Water
Content
•
1
5
Gray clay, very plastic
CH
57
27
30
57.4
Earth 440*
Consultants Inc.
GEOTECHNICAL ENGINEERING & GEOLOGY
Atterberg Limits Test Data
PROPOSED MULTI FAMILY RESIDENCE
TUKWILA, WASHINGTON
Proj. No.2739 I Date Sept.' 85 1Plate 12
"CITY OF TUKWILA - Planning Dep anent
APPLICATION TIMETABLE CHECKLIST
Project Schneider Homes, Inc. File #(s) 86 -31 -SUB
Location SW corner S. 151 St /65 Av S. intersection
Pre - application meeting date
Pre -app. #
SEPA # EPIC -334 86
Control # CN -86 -191
100.00 (EPIC)
Date application received 6/13/86 Fees $190.00 (SUB) 'Receipt # 1865
Kroll page 334E Qtr- Sec- Twp -Rng 23 -23 -4 NE Tax Lot #
GENERAL INFORMATION
Request
Subdivision
Description of project Single family detached residential subdivision - 14 lots
APPLICATION INFORMATION
Contact Person Jim Egge Phone 77(v�
Address Zip
Property Owner Gerald Schneider
Phone
Address Zip
Contract Purchaser Phone
Address Zip
PUBLIC NOTICE REQUIREMENTS /DEADLINES
Notice publication deadline 7/11/86 Date published 7/13/86
Notice to property owners deadline 7/14/86 Date mailed
Notice posted on property deadline Date posted
3 notices posted on property
Notice of Shoreline app. deadline n/a 1st notice published
30 day comment period ends - 2nd notice published
ENVIRONMENTAL REVIEW
Comment period: X Yes No 15 day deadline from action 7/10/86
Date routed Due back All comments received
Additional information required
Date submitted
Date routed Due back All comments received
DNS issued v4litigated DNS issued EIS required Date 7/WV,
BOARD OF ADJUSTMENT /PLANNING COMMISSION
Meeting date(s) 7/24/86 Date of final action
Approved Approved with conditions Denied
Conditions
Appeal deadline Appealed: Yes No
Shoreline Permit sent to DOE Date DOE received
30 day appeal period ends
CITY COUNCIL Transmittal deadline: 8/4/86 Next regulat meeting: 8/18/86
Hearing date assigned
Results of Hearing
Ordinance or Resolution assigned
(23 /ATC)
Effective date
LAND USE MAP UPDATED ZONING MAP UPDATED