HomeMy WebLinkAboutSEPA E98-0029 - CITY OF TUKWILA / CITY HALL - PARKING LOT EXPANSIONCITY HALL PARKING
LOT EXPANSION
CONSTRUCT THREE PARKING
LOTS FOR CITY
HALL/MINOLTA/XEROX
& HOUSING AUTHORITY
15447 65T" AVE. S.
E98-0029
City of Tukwila John W. Rants, Mayor
Department of Community Development Steve Lancaster, Director
Notice of Decision
March 26, 1999
To: Applicant
Parties of Record
This notice is to confirm the decision reached by the Tukwila Board of Architectural
Review on Thursday, March 25, 1999. The Board of Architectural Review voted to
approve the design of the three parking lots and the landscaping plan based on the
findings and conclusion in the staff report dated March 18, 1999.
This letter is issued pursuant to the Permit Application Types and Procedures, Tukwila
Municipal Code Zoning Chapter, (18.104.170) on the following project and permit
approvals.
Project
File Number: L98-0089
Associated Files: E98-0029
Applicant: City of Tukwila
Request: Construct three separate parking lots totaling 90 stalls to serve
Tukwila City Hall/ Minolta Building; the Xerox Building and the
King County Housing Authority.
Location: 15447 65th Avenue South
SEPA Determination: DNS
Project materials including the application, any staff reports, and other studies related to
the permits are available forinspection at:
Tukwila Department of Community Development;
6300 Southcenter BL, Suite 100; Tukwila, WA 98188
Monday through Friday; 8:30 a.m. - 5:00 p.m.
The planner managing the project is Carol Lumb, who may be contacted at 431-3661 for
further information.
This decision may be appealed to the Tukwila City Council pursuant to TMC 18.104.010
E. by filing a Notice of Appeal within 14 calendar days from the date of the issuance of
this Notice of Decision (TMC 18.116.010). Information on the content of the Notice of
Appeal may be obtained from the Department of Community Development at the address
noted above.
c:\carol\citypkg\hotdec.doc
6300 Southcenter Boulevard, Suite #100 • Tukwila, Washington 98188 • (206) 431-3670 • Fax (206) 431-3665
I
AFFIDAVIT
fl Notice of Public Hearing
O Notice of Public Meeting
ElBoard of Adjustment Agenda
Packet
LiBoard of Appeals Agenda
Packet
flPlanning, Commission Agenda
Packet
0 Short Subdivision Agenda
Packet
OF DISTRIBUTION
hereby declare that:
0 Notice of Application for
Shoreline Management Permit
QShoreline Management Permit
wasdto each of the f sses on
4.1.4, lavavve
NDetermination of Non-
significance
0 Mitigated Determination of
Nonsignificance
Determination of Significance
and Scoping Notice
ONotice of Action
Official Notice
Other
0 Other
Name of Project r� Signature
File Number
i
I,
AFFIDAVIT OF DISTRIBUTION
VQJU 6)A-- hereby declare that:
Notice of Public Hearing` Determination of Non-
significance
Notice of Public Meeting
OBoard of Adjustment Agenda
Mitigated Determination of
Nonsignificance
Determination of Significance
Packet and Scoping Notice
OBoard of Appeals Agenda
Packet
OPlanning Commission Agenda
Packet
fShort Subdivision Agenda
Packet
O Notice of Application for
Shoreline Management Permit
Shoreline Management Permit
Notice of Action
Official Notice
Other
Other
was mailed to each of the following addresses on
Name of Pro j ectc3a'"'` Signature
File Number
City of Tukwila John W. Rants, Mayor
Department of Community Development Steve Lancaster, Director
MARCH 12, 1999
CITY OF TUKWILA
NOTICE OF HEARING
PROJECT INFORMATION
The City of Tukwila has filed an application for Design Review, Number L98-0089, to construct
three separate parking lots on a 3.2 acre site north of Tukwila City Hall, at 15447 65th Avenue
South. The parking lots are a 51 stall parking lot to supplement the existing City Hall and Minolta
parking lots, a 20 -stall parking lot for use by the Xerox building and a 20 -stall parking lot for the
King County Housing Authority (construction costs to be paid by the Housing Authority).
You are invited to comment on the project at a public hearing scheduled for March 25, 1999 at
7:00 p.m. before the Board of Architectural Review. The hearing will take place at City Hall in
City Council Chambers, 6200 Southcenter Blvd. To confirm the time and date before the hearing,
call the Department of Community Development at 431-3670. For further information on this
proposal, contact Michael Jenkins at 431-3685 or visit our offices at 6300 Southcenter Boulevard,
Suite #100, Monday through Friday, 8:30 a.m. to 5:00 p.m.
Permits applied for include:
• Design Review
Other known required permits include:
• SEPA Checklist
• Land Altering Permit
FILES AVAILABLE FOR PUBLIC REVIEW
The project files are available at the City of Tukwila. To view the files, you may request them at
the permit counter of the Department of Community Development (DCD), located at 6300
Southcenter Boulevard #100.
c:\carolkitypkg\pubnot.doc
6300 Southcenter Boulevard, Suite #100 • Tukwila, Washington 98188 • (206) 431-3670 • Fax (206) 431-3665
• •
CITY OF TUKWILA
DETERMINATION OF NONSIGNIFICANCE (DNS)
DESCRIPTION OF PROPOSAL:
CONSTRUCTION OF A 90 SPACE PARKING LOT
BY THE DEPARTMENT OF PUBLIC WORKS. PROJECT WILL
INCLUDE STORM DRAINAGE, LANDSCAPING AND
ILLUMINATION.
PROPONENT: CITY OF TwolIcIA,
LOCATION OF PROPOSALINCLUDING.STREET ADDRESS.,IP-,,A4V4
— -•
ADDRESS:,,15447,65-AV
PARCEL NO,:' -359700=6:11'20
SEC/TWN/RNG"::- •
LEAD AGENCY:; CITY OF.jUKWILAC FILE NO Et'C-0fl29
/
The City, has determined that. theproposal does not havea-pii-ob'able
signifiCant adv'erse impact_on th*en-Vironment. An enVironmental
impact.statement (EI) Is not-reduireOnlder RCW 43.216.00(2)(4.
This decision w3: made after review of-a'icOmplted envirOnMental;
checklist and other i-nforMatiol,onfyleAaith„,-the lead agency. Th,l's
information is a014able to.the,publi-c on-i-eoue.7.t.
;
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This determinatiOn is final:and signed1
-this': .-, dav o JAAALAT
,..
•
'4 •
Steve LancSter, ResponScible OfficJal
City of TukWiAa, J'20) 431.73670
6300 Southcente:c BouLevard
Tukwi ia. WA '981'38
, . .
,
_ .
Copies of the proced4retTfor SEPA ,appeals',are available with
..,
Department of Community,-.„DeVelapment. --- ,-.,-,
-_,
the
******
AFFIDAVIT
I,YTAIV-
ONotice
of Public Hearing
Notice of Public Meeting
EBoard of
Packet
fl Board of
Packet
fl Planning
Packet
Adjustment Agenda
Appeals Agenda
Commission Agenda
fShort Subdivision Agenda
Packet
OF DISTRIBUTION
hereby declare that:
.E Notice of Application for
Shoreline Management Permit
QShoreline Management Permit
determination of Non-
significance
Mitigated Determination of
Nonsignificance
Determination of Significance
and Scoping Notice
O Notice of Action
was mailed to each of the following
Name of Project Fj
File Number (2 (.
Official Notice
Other
Other
addresses on
3/0/?'f
q -ave
Signature
MEMORANDUM
March 4, 1999
To: Steve Lancaster, Director
Fm: Carol Lumb,ss� Planner
Re: Project File No. E98-0029: City Hall Parking Lot Expansion
Project Description:
Construct a 51 stall parking lot to supplement the existing City Hall parking lot, a 20 stall parking
lot for use by the Xerox Building and a 20 stall parking lot for the King County Housing Authority
on a 3.2 acre site north of City Hall.
Proponent:
City of Tukwila
Location:
15447 65th Avenue South
Date prepared:
February 19, 1999
Lead Agency:
City of Tukwila, Department of Community Development
Challenges to Document:
None
Other Agencies of Jurisdiction:
None
Recommendation:
Determination of Non -Significance (DNS)
City Hall Parking Lot
Determination of Nonsignificance
• •
Summary of Primary Impacts:
Earth
The site is characterized by steep slopes up to 80% in the western portion of the site
which have been classified as Class 3 Landslide Hazard. The geotechnical report by
Terra Associates states that based on the detailed site investigation and subsurface
explorations, the site is not a landslide hazard area. The soils are comprised of silly sand
and weathered bedrock. The environmental checklist estimates that approximately 2500
cubic yards of material will be excavated from the site and used as structural backfield
material if suitable. Approximately, 39% of the site will be covered with asphalt parking
areas and concrete sidewalks. Erosion control measures will be needed throughout
project construction to avoid sedimentation and erosion from the site. Straw or securely
anchored plastic sheeting will be used to cover exposed silly sands. Silt fences, straw
bale check dams and other standard erosion control measures will also be in place
throughout construction.
Air
Standard exhaust emissions from construction vehicles would result from construction
activities. When the project is completed, parking will be provided for 90 passenger
vehicles. Standard emissions from these vehicles will be present as a result of the
completed project.
Water
The project site is approximately 600 feet west of the Green River. No work will take
place over, in or adjacent to the River nor will any surface water be withdrawn or
diverted for this project. Storm water will be collected from impervious surfaces with
the use of catch basins and piped to a wet pond. Water will be discharged from the wet
pond to the City's stormwater drainage system. Standard road and automotive pollutants
found in storm water systems collected on the surface of the parking lot will enter the
storm system.. Some treatment/settling will occur in the wet pond.
Plants
The site is primarily undeveloped and contains a variety of trees throughout the site
including alder, maple, aspen chestnut, apple, hazelnut, fir, cedar and holly,. A twenty -
foot wide landscape buffer will be installed on the north side of the site, as a buffer
between the parking lot and the residential development on the north. A landscaping
plan was submitted with the application. The landscaping plan provides trees along the
street providing access to the site from 65th Avenue South, trees as a screening buffer on
the perimeter of the parcel and landscaping throughout the parking lot. As many of the
existing trees as possible will be retained.
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2
City Hall Parking Lot
Determination of Nonsignificance
• •
Animals
Songbirds , crows and squirrels are the birds and animals observed on the site.
Neighbors have also observed raccoons on the site. No threatened or endangered species
are known to exist on the site. While wildlife habitat will be removed through the
construction of the parking lots, there will still be a majority of the site (61%) that will
remain undeveloped, either in its native state or as landscaped area, and available for
habitat.
Energy/Natural Resources
Electricity will be used to provide lighting in the parking lot. No other types of energy
are expected to be needed.
Environmental Health
Temporary noise impacts due to construction are anticipated.. Low level traffic noise
associated with cars in a parking lot would be present, generally during the working
hours of 7:00 a.m. to 6:00 p.m.
Land/Shoreline Uses
The site is vacant and zoned commercial. The remnants of an old building foundation
are located on the eastern portion of the site. Adjacent on the north and west and east are
residential development, with a City Park across 65th Avenue South. The existing City
Hall and Minolta Building are on the south side of the site. The current zoning
classification is Office. The current Comprehensive Plan designation is also Office. A
total of 91 parking stalls will provided in three separate lots to serve the City
Hall/Minolta Building, Xerox building and the King County Housing Authority.
Housing
Not applicable.
Aesthetics
The tallest structures on the site will be light poles to illuminate the parking area, which
will be approximately 12 feet tall. A 20 foot landscape border will be installed between
the project and the residential property lines on the north and west sides as a buffer. The
existing vegetation will be supplemented by tall and full form evergreen trees. The
foreground will be planted with mostly evergreen shrubs to soften the parking lot
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3
City Hall Parking Lot
Determination of Nonsignificance
• •
appearance. The landscaping will be balanced with the need to provide a safe
environment to park and leave vehicles.
Light/Glare
The parking lot will be lighted, as noted above with 12 -foot tall light poles The lights
will be directed in such a way that there will not be impacts off-site.
Recreation
Tukwila Park is located to the east of the site, across 65th Avenue South. Hazelnut Park
is located to the north at approximately South 147th Street and 59th Avenue South.
There is a trail along the Green/Duwamish River to the east. None of these recreational
facilities will be impacted by the proposed parking lot. .
Two picnic tables and two trash cans will be provided for use by City employees. The
tables will be built to Park Department standards and accessed by pedestrian paths.
Historic/Cultural Preservation
Not applicable.
Transportation
The site will be access by 65th Avenue South and through the City Hall and Minolta
Building parking lots. There is transit access on Southcenter Boulevard. The City Hall
parking lot addition is needed due to the use of many of the existing City Hall spaces by
District Court clients throughout the week. The 20 -stall parking lot for the Xerox
Building is proposed to replace an existing parking lot that is currently used by both
Xerox Building and City employees. The King County Housing Authority Parking Lot
addition is due to the current small size of its existing parking lot. The Housing
Authority would contract with the City to construct the lot and would reimburse the City
for the cost of construction. It is not anticipated that the parking lots will generate
additional trips. Up to four parking stalls in the existing Minolta parking lot will be
dedicated for car pool participants as part of the City's commute trip reduction program.
The Public Works Department has determined that the parking lot project is exempt
from the Traffic Concurrency Standards adopted in TMC 9.48. The exemption is based
on the fact that no change in use is proposed for either City Hall or the Minolta Building.
Additional parking space is needed at City Hall to accommodate the increase in
Municipal Court traffic; as a result, employee parking must be shifted to another site.
Additional parking is needed at the Minolta Building to accommodate the increase of
visitors to the Permit Center for Planning and Public Works related permits. In addition,
more City -owned vehicles are being parked at both City Hall and the Minolta Building
which then displaces both employees and visitors from parking.
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4
City Hall Parking Lot
Determination of Nonsignificance
• •
Public Services
The proposed parking lots are not expected to generate additional need for public
services.
Utilities
Utilities currently available at the site include electricity, natural gas, water, refuse
service, telephone, storm water and sanitary sewer. On-site storm drainage facilities will
be constructed which will connect to the off-site City of Tukwila storm drainage
facilities. No additional utilities are anticipated to be needed as a result of the parking lot
construction other than electricity for lighting.
Recommendation
Determination of Nonsignificance
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P UBLIC WORKS DEPT_
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CITY HALL PARKING LOT EXPANSION
FEBRUARY ALTERNATE #4
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City of Tukwila
Department of Public Works
January 22, 1999
Dear Resident/Property Owner:
RE: City Hall Parking Lot Expansion Project
OPEN HOUSE
John W Rants, Mayor
Ross A. Eamst, P. E., Director
We are continuing the design and permitting of the City Hall Parking Lot Expansion
project for the vacant lot north of 6300 and 6400 Southcenter Boulevard. A preliminary
design has been prepared and we would like to review that with you. An open house has
been scheduled for:
Wednesday, February 17, 1999
4:00 p.m. to 7:00 p.m.
Tukwila Public Works
6300 Southcenter Boulevard, Conference Room No. 5
This mailing is being sent to all residents and property owners within 500 feet of the
parcel boundary.
If you have any questions, please bring them to the open house, or feel free to call me at
(206) 433-0179.
Sincerely,
ida447-\
Bob Giberson, P.E.
Senior Engineer
file: 95-BG01-7
P:\projects\95bg01 \opnhaus.doc
6300 Southcenter Boulevard, Suite #100 • Tukwila, Washington 98188 • Phone: (206) 433-0179 • Fax (206) 431-3665
•
City of Tukvvila John W Rants, Mayor
Department of Community Development Steve Lancaster, Director
NOTICE OF APPLICATION
DATED JANUARY 11, 1999
The following applications have been submitted to the City of Tukwila Department of Community
Development for review and decision.
APPLICANT: City of Tukwila
LOCATION: 15447 65th Avenue South, Tukwila, WA
FILE NUMBERS: L98-0087, E98-0029
PROPOSAL: Construct a 90 -space expansion of City Hall parking lot, including
storm drainage, landscaping and lighting. The expanded parking lot
will connect the City Hall parking lot through to 65th Avenue South.
OTHER REQUIRED PERMITS: Land Altering, Storm Drainage, Tree Permit
These files can be reviewed at the Department of Community Development, 6300 Southcenter Blvd.,
#100, Tukwila, WA. Please call (206) 431-3670 to ensure that the file(s) will be available.
OPPORTUNITY FOR PUBLIC COMMENT
You can submit comments on this application. Due to an error in the original mailing, the comment
deadline has been extended. You must submit your comments in writing to the Department of
Community Development by 5:00 p.m. on Friday, February 5, 1999. A public meeting has been
scheduled for 4:00 - 7:00 p.m., Wednesday, February 17, 1999 at Tukwila City Hall, 6200
Southcenter Boulevard (see enclosed notice). This matter is also scheduled for a public hearing
before the Board of Architectural Review on March 25, 1999. If you are interested in attending the
hearing, please contact the Department at (206) 431-3670 to ensure that the hearing is still scheduled for
this date. If you cannot submit comments in writing by the cutoff date indicated above, you may still
appear at the hearing and give your comments on the proposal before the Planning Commission. If you
have questions about this proposal contact Carol Lumb, the Planner in charge of this file. Anyone who
submits written comments will become parties of record and will be notified of any decision on this
project.
APPEALS
You may request a copy of any decision by the Planning Commission on a project or obtain information
on your appeal rights by contacting the Department of Community Development at 431-3670. A
decision from the Planning Commission may be appealed to the City Council.
DATE OF APPLICATION:
NOTICE OF COMPLETE APPLICATION:
NOTICE OF APPLICATION POSTED:
c:\carol\citypkg\notapp2.doc
November 18, 1998
December 15, 1998
January 11, 1999
6300 Southcenter Boulevard Suite #100 • Tukwila, Washington 98188 • (206) 431-3670 • Fax (206) 431-3665
City of Tukwila
Department of Community Development
NOTICE OF APPLICATION
DATED JANUARY 11, 1999
John W. Rants, Mayor
Steve Lancaster, Director
The following applications have been submitted to the City of Tukwila Department of Community
Development for review and decision.
APPLICANT:
LOCATION:
FILE NUMBERS:
PROPOSAL:
City of Tukwila
15447 65th Avenue South, Tukwila, WA
L98-0087, E98-0029
Construct a 90 -space expansion of City Hall parking lot,
including storm drainage, landscaping and illumination. The
expanded parking lot will connect City Hall parking lot through
to 65th Avenue South.
OTHER REQUIRED PERMITS: Land Altering, Storm Drainage, Tree Permit
These files can be reviewed at the Department of Community Development, 6300 Southcenter
Blvd., #100, Tukwila, WA. Please call (206) 431-3670 to ensure that the file(s) will be available.
OPPORTUNITY FOR PUBLIC COMMENT
You can submit comments on this application. You must submit your comments in writing to
the Department of Community Development by 5:00 p.m. on January 25, 1999. This matter is
also scheduled for a public hearing on February 25, 1999. If you are interested in attending the
hearing, please contact the Department at (206) 431-3670 to ensure that the hearing is still
scheduled for this date. If you cannot submit comments in writing by the cutoff date indicated
above, you may still appear at the hearing and give your comments on the proposal before the
Planning Commission. If you have questions about this proposal contact Carol Lumb, the Planner
in charge of this file. Anyone who submits written comments will become parties of record and will
be notified of any decision on this project.
APPEALS
You may request a copy of any decision by the Planning Commission on a project or obtain
information on your appeal rights by contacting the Department of Community Development at
431-3670. A decision from the Planning Commission may be appealed to the City Council.
DATE OF APPLICATION:
NOTICE OF COMPLETE APPLICATION:
NOTICE OF APPLICATION POSTED:
c:\carol\citypkg\notapp.doc
November 18, 1998
December 15, 1998
January 11, 1999
l.Znn Cn..thnnntnr. An.11n11e1.4 Cr Si' #1nil - 7'..L.. di U7. hJ...r... 11o100 - ionht w01 o.4v) _ J..... ions) 4Or OL 6c
City of Tukwila
•
•
John W. Rants, Mayor
Department of Community Development Steve Lancaster, Director
NOTICE OF COMPLETE APPLICATION
DATED DECEMBER 15,1998
TO: Bob Giberson, Sens , igineer
FM: Carol Lumb, Assdc to Planner
RE: Proposed City Hall Parking Lot: File #s E98-0029 and L98-0087
Thank you for sending us the Coordinating Review memorandum regarding the parking
lot expansion. The comments from DCD on this project will come in the context of the
SEPA and permit review. Your application to construct a 90 -stall parking lot expansion to
the existing City Hall parking lot has been found to be complete on December 15, 1998
for the purposes of meeting state mandated time requirements. This project is subject to
environmental review (SEPA) and design review by the City's Board of Architectural
Review. I am the planner assigned to the project.
The next step in the review process is for you to install three notice boards in the
following locations: Southcenter Boulevard, in front of the Minolta Building, on 62n
Ave. South at the entrance to City Hall and on 65th Avenue South, where the parking lot
will exit, within 14 days of the date of this letter, no later than December 29, 1998. If you
did not receive information on how to install the sign with your application packet, please
let me know. You also must obtain a laminated copy of the Notice of Application to post
on the board. Please let me know when the sign is ready for installation so that I can
prepare the notice that you will post and that will be mailed out to the surrounding
property owners. After installing the sign with the laminated notice, please return the
signed Affidavit of Posting to our office. The 14 -day comment period on the parking lot
expansion begins when the site is posted and the Notice of Application has been sent out
to property owners within 500 feet of the site.
Just for your information, the Fire Department noted in its preliminary review of the
parking lot that the maximum grade for the road is 15%.
The determination that the application is complete does not preclude the ability of the City
to require that you submit additional plans or information, if in our estimation such
information is necessary to ensure the project meets the substantive requirements of the
City or to complete the review process. I will be contacting you soon to discuss this
project and the timing of the review of the project by the Board of Architectural Review.
If you wish to speak to me sooner, feel free to call me at 431-3661 or stop by my desk.
cc: Jack Pace, Planning Manager
c:\caro I\pkglot\com lete
6300 Southcenter Boulevard, Suite #100 • Tukwila, Washington 98188 • (206) 431-3670 • Fax (206) 431-3665
PRELIMINARY GEOTECHNICAL REPORT
Tukwila Parking Lot
15400 Block of 65th Avenue South
Tukwila, Washington
Project No. T-4110
Terra. Associates, Inc.
Prepared for:
City of Tukwila
c/o Roth and Hill Engineering Partners, Inc.
Bellevue, Washington
CITY OFTUKWILA September 29, 1998
NOV81998
PERMIT CENTER
ERRA ASSOCIAT S, Inc.
Consultants in Geotechnical Engineering, Geology
and
Environmental Earth Sciences
September 29, 1998
Project No. T-4110
City of Tukwila
c/o Mr. Mark Cole, P.E.
Roth and Hill Engineering Partners, Inc.
14450 NE 29th Place, Suite 101 -
Bellevue, Washington 98007
Subject: Preliminary Geotechnical Report
Tukwila Parking Lot
15400 Block'of 65th Avenue South
Tukwila, Washington.
Dear Mr. Cole:
As requested, we have conducted a preliminary geotechnical engineering study for the subject project.
The attached report presents our findings and recommendations for the geotechnical aspects of the
anticipated project design and construction.
Our field exploration indicates the site is generally underlain by variably thick layers of very dense silty
sand and moderately to completely weathered sandstone of the Renton Formation. Excavation depths
may be limited by the some of the less weathered rock due to excavation difficulty.
In our opinion, the subsurface conditions at the site are suitable for the planned parking lot construction,
provided the recommendations presented in this report are incorporated into project design and
construction. The competent nature of the on-site native soils and weathered rock indicates the site's
slopes are stable and, with proper grading, will not be impacted by the proposed construction.
12525 Willows Road, Suite 101, Kirkland, Washington 98034 • Phone (42)821.7.777
Mr. Mark Cole, P.E.
September 29, 1998
We appreciate the opportunity to be of service during this phase of the project. We trust the information
presented in this report is •.1,'ent for your current needs. If you have any questions or require
additional informatio
Sincerely yours,
TERRA ASSOC
9-29-93
Kevin P. Roberts, P.E.
Project Engineer
Tifeodore J. Schep P.E.
Principal Engine
KPR/TJS:dvp
Project No. T-4110
Page No. ii
TABLE OF CONTENTS
• Page
1.0 Project Description 1
2.0 Scope of Work 1
•
3.0 Site Conditions • 2
3.1 Surface 2
3.2 Soils 2
4.0 Geologic Hazards 3
4.1 Erosion 3
4.2 Landslide 3
•
5.0 Discussion and Recommendations / 3
5.1 General 3
5.2 Subgrade Preparation and Grading 4
5.3 Cut and Fill Slopes 6
5.4 Excavations 6
Retaining Walls 6
5.6 Drainage 7
5.7, . Utilities 7
5.8 Slope Stability 7.
5.9 Pavements 7
5.10 Environmental Checklist 8
.6:0 Additional Services 8
7.0 Limitations 8
Figures
Vicinity Map Figure 1
Exploration Location Plan Figure 2
Retaining Wall Drainage Detail Figure 3
Appendices
Field Exploration and Laboratory Testing Appendix A
Environmental Checklist
Appendix B
(i)
• •
Preliminary Geotechnical Report
Tukwila Parking Lot
15400 Block of 65th Avenue South
Tukwila, Washington
1.0 PROJECT DESCRIPTION
The project will consist of the construction of a parking lot in the 15400 Block of 65th Avenue South in Tukwila,
Washington. The location of the project site is shown on the Vicinity Map, Figure 1.
We were provided with two undated conceptual site plans prepared by the City of Tukwila Public Works
Department. The site plans show two alternate parking lot layouts (Alternates A and B). Each layout indicates
that construction will occur north and adjacent to existing parking areas east of City Hall. Access to the proposed
parking areas will be from the existing southern parking locations, and from a new access drive leading westward
to the site from 65th Avenue South.
Plans indicating proposed grading configurations are not available at this time. The presence of gentle to steep
slopes at the site indicates moderate grading will be required to establish parking lot grades.
The recommendations contained in this report are based on our current understanding of the project. Once project
drawings and specifications are made available, we should review them to verify that these preliminary
recommendations have' been properly interpreted in design, and to provide additional recommendations if
required.
2.0 SCOPE OF WORK -
On August 17, 1998, we excavated 9 backhoe test pits at the site to depths ranging between 5.0 and 10.5 feet
below existing surface grades: Using the information obtained from the subsurface exploration, we performed
analyses to develop preliminary geotechnical recommendations for project design and construction. Specifically,
this report addresses the following:
• Soil and groundwater conditions
• Subgrade preparation and grading
• General site stability
• Structural fill
• Cut and fill slopes
• Excavations
• Retaining walls
• Surface and subsurface drainage
• Pavement sections
• • September 29, 1998
Project No. T-4110
3.0 SITE CONDITIONS
3.1 Surface
The subject property is bounded to the west and south by office complexes. A residential property and 65th
Avenue South bound the site to the north and east, respectively.
The site is primarily undeveloped. A small City parking lot, accessed from adjacent southern parking areas, is
located in the central portion of the site. We noted remnants of a small structure's concrete slab and foundations
in the northeastern part of the site. Short rockeries are also present in this area, adjacent to a driveway accessing
the southeastern corner ofthe property.
The site is situated on an overall east -facing hillside. An approximately 20 -foot high, east -facing slope rises up
from 65th Avenue South to relatively flat terrain in the east -central part of the site. This slope shows an overall
inclination of 30 percent, with locally steeper parts standing at 80 percent. The site's central portion contains a
broad swale with side slopes ranging to a maximum inclination of approximately 40 percent. West of the swale,
the ground surface rises gradually to gently sloping areas in western site locations. An approximately 30 -foot
high (maximum) south -facing cut slope extends downward from the southwestern site corner to the adjacent, City
parking lot. All slopes were vegetated with shrubs and/or groundcover and showed no signs of significant erosion
or instability. In addition, no zones of emergent groundwater were observed on the slopes. •
At the time of our visit, we did not observe any standing or flowing water at the site. Vegetation primarily
consisted of short grasses- inthe open areas, shrubs, and a variety of scattered small to mature deciduous and
coniferous trees. -
3.2 Soils
Excavation of the test pits at the site revealed a 6- to 18 -inch thick layer of organic topsoil or surficial fill. All of
the test pits showed glacial till or till -like soils to depths ranging from 1.5 feet to 10.0 feet below existing site
grades. These soils consisted of very dense, silty fine to medium sand with gravel and gravelly silty sand. The
till soils contained variable amounts of, cobbles and, as shown by Test Pits TP -3, TP -5, and TP -7 through TP -9,
numerous small to large boulders. Test Pits. TP -1, TP -5, and TP -7 through TP -9 were terminated within the
glacial till.
In Test Pits TP -2 through TP -4 and TP -6, the glacial till or till -like soils were underlain by weathered sandstone
of the Renton Formation. In Test Pits TP -2 through TP -4, the sandstone was completely weathered to dense silty
sand. In Test Pits TP -3, TP -4, and TP -6, we encountered fractured, moderately to highly -weathered sandstone at
depths ranging from 1.5 feet to 8.5 feet. These test pits were terminated within the moderately to highly -
weathered sandstone due to practical backhoe refusal. No groundwater or caving of the test pit walls was noted
during excavation of the test pits.
Page No. 2
• September 29, 1998
Project No. T-4110
The Geologic Map of the Des Moines Quadrangle, Washington, by Howard H. Waldron (1962) shows the site
geology mapped as Tertiary intrusive rocks. The variably -weathered sandstone observed at the site correlates
better with the Renton Formation (Ter) .mapped approximately one-fourth mile north of the site. In addition, the
glacial till noted in some of the test pits correlates with the "Ground moraine deposits (Qgt)" mapped one-eighth
mile west of the site.
The Test Pit Logs in Appendix A present more detailed descriptions of the subsurface conditions encountered.
The approximate test pit locations are shown on Figure 2.
4.0 GEOLOGIC HAZARDS
4.1 Erosion
The soils encountered on-site are classified as "Urban Land" (Ur) by the Soil Conservation Service (SCS)..
According to the classification, the erosion hazard of these soils is "slight to moderate." With the existing slope
gradients ranging up to 80 percent, the silty sand soils will have a high potential for erosion when exposed during
construction.
4.2 Landslide
The site contains slopes that are inclined in excess of 40 percent, as well as slopes ranging from 20 to 40 percent
that are underlain by relatively impermeable soils or bedrock. These areas are classified under City of Tukwila
Municipal Code. as "Class 3 Landslide Hazard" areas.
We contacted Tukwila. Public Works to inquire if any records exist of past soil instability on or adjacent to. the
site. A City representative indicated he was not aware of documented soil instability in the site's vicinity. During
our site visit, we did not observe any surface features indicating pastor current slope stability problems. Based on
these observations and information, the site geology, and site topography, it is our opinion that the site is not a
landslide hazard area.'
5.0 DISCUSSION AND RECOMMENDATIONS
5.1 General
Our subsurface exploration indicates that competent, glacially -derived soils and weathered rock underlie the site.
Accordingly, pavement sections constructed on the site may be supported on the silty sand'or weathered rock, or
on structural fill placed on these soils.
Page No. 3
• September 29, 1998
Project No. T-4110
At a depth of five feet, Test Pit TP -6 encountered hard, moderately -weathered sandstone that was very difficult to
excavate with a backhoe. Based on this, cut and fill depths for the project may be limited in some locations. The
contractor should expect some difficulty excavating the moderately -weathered material during grading operations.
Based on our field observations, we do not expect unusual difficulty in excavating the overlying completely to
highly weathered sandstone. However, because of its fines content and potential forlargeclasts, special attention
will be required during placement and compaction of this material as structural fill. If difficulties are encountered
during compaction of the weathered rock material, it may be more desirable to import soil to the site for use as
structural fill.
The following sections provide preliminary recommendations regarding the above issues and other geotechnical
design considerations. These recommendations should be incorporated into the final design drawings and
construction specifications.
5.2 Subgrade Preparation and Grading
To prepare the site for construction, all vegetation, organic surface soils, and other unsuitable materials should be
stripped and removed from the areas under construction. Surface stripping depths of 6 to 18 inches should be
expected to remove organic topsoil and existing surficial fill. Organic topsoil will not be suitable for use as
structural fill but may be used for limited depths in non-structural areas or for landscaping purposes.
Once clearing and ,grubbing operations are complete, cutand 'fill operations to establish desired grades can be
initiated. We recommend placing pavement sections on undisturbed surfaces of the native medium dense to very
dense silty sand, moderately to completely -weathered sandstone, or suitably compacted structural fill placed on
these materials. Prior to placing fill, we recommend proofrolling all exposed surfaces to determine if any isolated
soft and yielding areas are present. Proofrolling should also be performed in cut areas that will provide direct
support for new construction. A representative of Terra Associates, Inc., should observe all proofrolling
operations. We also recommend field evaluations at the time of construction to verify stable subgrades.
If excessively yielding areas are observed, they should be cut to a firm subgrade and filled to grade with structural
fill. In pavement areas, if the depth of excavation to remove unstable soils is excessive, use of geotextile fabric,
such as Mirafi 500X or equivalent, in conjunction with structural fill can be considered in order to limit the depth
of removal. In general, a minimum of 18 inches of clean, granular structural fill over the geotextile fabric should
establish a stable bearing surface.
Review of the conceptual site plan indicates fill placement may occur on sloping subgrades. Where fill is placed
on subgrades inclined at greater than 25 percent, we recommend benching and keying fill slopes into competent
native soils as shown on Figure 3.
Abundant small to large boulders were observed during excavation of several of the test pits. During grading, the
contractor should be prepared to remove them from site soils prior to reuse as structural fill.
Page No. 4
•
September 29, 1998
Project No. T-4110
Extreme care should be taken to ensure that exposed surfaces of the silty sand and weathered rock do not become
disturbed due to weather and construction traffic. It may be necessary to protect pavement area subgrades with a
layer of crushed rock to guard against soil degradation.
Laboratory sieve results indicate most of the on-site soils and weathered rock contain a relatively high fraction of
fines (silt and clay particles), which will make them particularly sensitive to moisture conditions. The ability to
use these materials from site excavations as structural fill will depend on their moisture content and the prevailing
weather conditions at the time of construction. Our field and laboratory results also show that the near -surface till
soils at the site are near their optimum moisture content. The results also show that the moisture contents increase
with depth in the till soils and completely weathered sandstone: Reuse of these deeper materials will likely entail
scarification and drying prior to compaction.
We anticipate the weathered and fractured sandstone at the site can be reused as structural fill. This material
contains variable amounts of silt as well as minerals that typically weather to clay. The presence of silt and clay
will influence its compactibility from the standpoint of sensitivity to moisture. Moreover, excavation of the
sandstone will likely produce large clasts of intact material that will need to be broken to smaller sizes to facilitate
placement and compaction as fill. To facilitate proper compaction of these soils, consideration should be given to
using a sheep's -foot roller. The feet will break up larger clasts and cause mixing of the clasts and clay; thereby
improving the homogeneity of the material and; thereby, its compaction.
If grading activities must take place during wet weather or on a wet subgrade, the owner should be prepared to use
wet weather structural fill. For this purpose, we recommend using a granular soil that meets the following
grading requirements:
U.S. Sieve Size
Percent Passing
- . 3 inches
100
• No. 4
75 maximum
No. 200
5 maximum*
*Based on the 3/4 -inch fraction.
Prior to use, Terra Associates, Inc., should examine and test all on-site or imported materials proposed for use as
structural fill.
Structural fill should be placed and compacted in accordance with City of Tukwila standards. At minimum, we
recommend that structural fill be placed in uniform loose layers not exceeding 12 inches and compacted to a
minimum of 95 percent of the soil's maximum dry density, as determined by ASTM Test Designation D-698
(Standard Proctor). The moisture content of the soil at the time of compaction should be within two percent of its
optimum, as determined by this standard. In non-structural areas or for backfill in utility trenches below a depth
of 4 feet, the degree of compaction can be reduced to 90 percent.
Page No. 5
5.3 Cut and Fill Slopes
September 29, 1998
Project No. T-4110
All permanent cut and fill slopes should be graded with a finish inclination of no greater than 2:1
(Horizontal:Vertical). All fill placed for embankment construction should meet the requirements for structural fill
as described in the Site Preparation and Grading section of this report. Structural fill slopes gradedto finish
inclinations steeper than 2:1 may be considered. However, it will be necessary to design and construct these
slopes using geogrid/geotextile reinforcement. We can provide design and construction recommendations for
steeper fill slope sections, if desired.
Once cleared of ' vegetative cover, the soils will be susceptible to surficial instability and erosion from.
concentrated surface water runoff if they are not suitably protected. During construction, soils exposed 'on
excavated slopes should be covered with straw or securely-anchoredplastic sheeting. Upon completion of
grading, slope faces should be appropriately vegetated or provided with other physical means to guard against
erosion.
5.4 Excavations
All excavations at the site associated with utility construction must be completed in accordance with Local, state,
or federal requirements. Based on current Occupational Safety Health Administration (OSHA) regulations, the
dense weathered sandstone and very dense till soils at the site would be classified as Group A. For temporary
excavations more than 4 feet in these materials, the side slopes should be completed with a gradient of .75:1 or
flatter. If there is insufficient room to complete the excavations in this manner, you may need to consider using
temporary shoring to support the excavations.
The above information is provided solely for the benefit of the owner and other design consultants, and should not
be construed to imply that Terra Associates, Inc., assumes responsibility for job site safety. It is understood that •
job site safety is the sole responsibility of the project contractor.
5.5 Retaining Walls
The earth pressures that develop on cantilevered (unrestrained) or restrained retaining walls will partly depend on
the quality of the wall backfill. We recommend placing and compacting wall backfill as structural fill.. Below
pavements, the backfill should be compacted to a minimum of 95 percent of its maximum dry unit weight; as
determined by ASTM Test Designation D-698 (Standard Proctor): In unimproved areas, the relative compaction
may be reduced to 90 percent. To prevent development of hydrostatic pressure, wall drainage must also be
installed. A typical recommended wall drainage detail is shown on Figure 4.
With wall backfill properly placed and compacted and drainage installed, unrestrained walls should be designed
for an active earth pressure imposed by an equivalent fluid weight of 35 pounds per cubic foot. (pcf) for horizontal
backfill and 50 pcf where the backfill is sloped to 2:1. At -rest earth pressures equivalent to fluids weighing 50 pcf
for horizontal backfill and 65 pcf for a 2:1 backslope may be used for restrained walls. Walls subject to traffic
surcharge should be designed for an additional wall height to two feet. .
Page No. 6
September 29, 1998
Project No. T-4110
The active earth pressure values given above assume that no other surcharge loads will act on the wall. If such
conditions exist, then the imposed loads must be included in the wall design. During construction, compaction of
backfill with a heavy roller that is too close to the wall could result in excessive wall pressures and damage to the
wall. To reduce the risk of damage to the wall due to compaction, backfill placed within five feet from the wall
should be compacted with hand -operated equipment.
5.6 Drainage
Final exterior grades should promote free and positive drainage away from site slopes at all times. To minimize
the potential for slope instability, it is essential that concentrated stormwater runoff be routed away from slopes or
properly tightlined to approved discharge points at the slope's toe.
The conceptual site plan shows a buried stormwater detention vault located at the southern terminus of 64th
Avenue South near the northern property line. We recommend routing stormwater from the vault to a suitable
discharge point.
5.7 Utilities
Utility pipes should be bedded and backfilled in accordance with American Public Works Association (APWA) or
City of Tukwila specifications. As a minimum, trench backfill, should be placed and compacted as structural fill
as described in the Subgrade Preparation and Grading section of this report.
5.8' Slope Stability
In general, the sloping soils and weathered rock at the site are stable with respect to static and seismic .loading.
This is due to the overall modest grades exhibited by the site's slopes, the relatively competent nature of the soils,
and the lack of groundwater. Based on our understanding of planned grading concepts, it is our opinion that there ._
will be no adverse impact to the current stability of the site slopes or those on adjacent properties. However, we
should review the final grading plan when it is available to complete a more detailed evaluation of the stability of
the site's soils in relation to placement of fill and other geotechnical considerations.
5.9 Pavements
Traffic loads on parking lot pavements will be relatively light, consisting primarily of those imposed by passenger
cars. Pavements should be constructed on subgrades prepared as described in the Subgrade Preparation and
Gradingsection of this report. Regardless of the degree of relative compaction achieved, the subgrade must be
firm and relatively unyielding before paving. Proofrolling the subgrade with heavy construction equipment
should be completed to verify this condition.
Page No. 7
• • September 29, 1998
Project No. T-4110
With a stable subgrade prepared as recommended, we recommend the following pavement sections:
• Two inches of asphalt concrete (AC) over four inches of crushed rock base (CRB).
• Two inches of AC over three inches of asphalt treated base (ATB)
The paving materials used should conform to the Washington State Department of Transportation (WSDOT)
specifications for Class B asphalt concrete, ATB, and CRB.
5.10 Environmental Checklist
We understand completion of a SEPA checklist is required for the project. Appendix B contains the completed
portion of the checklist entitled "B. Environmental Elements, 1. Earth."
6..0 ADDITIONAL SERVICES
Terra Associates, Inc., should review the final design and specifications in order to verify that earthwork and
foundation recommendations have been properly interpreted and incorporated into the project design and
construction. We should also provide geotechnical, services during construction in order to observe compliance
with the design concepts, specifications, and recommendations. This will also allow for design -changes if
subsurface conditions differ from those anticipated prior to the start of construction..
7.0 LIMITATIONS
We prepared this report in accordance with generally accepted geotechnical engineering practices. This report is
the property of Terra Associates, Inc., and is intended for specific application to the Tukwila Parking Lot project.
This report is for the exclusive use of City of Tukwila, Roth and Hill Engineering Partners, Inc., and their •
=$. authorized representatives. No other warranty, either expressed or implied, is.made.
The analyses and recommendations presented in this report are based upon data obtained from the test pits
excavated on-site. Variations in soil .conditions can occur, the nature .and extent of which may not become
• evident until construction. If variations appear evident, Terra Associates, Inc.; should be requested to reevaluate
the recommendations in this report prior to proceeding with construction.
Page No. 8
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REFERENCE:. THE
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WASHINGTON, PAGES
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4*- I .4.,,,,,,I •
686; 1998 EDITION.
.
. -
• VICINITY MAP , .. ,..
TUKWILA PARKING LOT
TUKWILA, WASHINGTON
TERRA -
itig.
•N
.5.5016fprizi • ASSOCIATES
Geotechnical
Proj. No. 4110.
Date SEPT. 1998
Figure 1
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APPROXIMATE SCALE
60 0 60
120 feet
LEGEND:
APPROXIMATE TEST PIT LOCATION
REFERENCE:
UNDATED SITE. PLAN PREPARED BY CITY
OF TUKWILA, CONTRACT No. 95—BG01,
ALTERNATE A.
TERRA
ASSOCIATES
' otechnical Consultants
EXPLORATION LOCATION PLAN
TUKWILA PARKING LOT
TUKWILA, WASHINGTON
Proj. No.4110
Dote SEPT. 1998
Figure 2
•
NEW STRUCTURAL FILL
MAXIMUM SLOPE GRADIENT: 2:1(H:V)
EXISTING
GRADE
•
SLOPE TO DRAIN
*xsx.
2 *41 ft t1/411
4%4
, s__Adski.N.w
••• • .1.. • •- . .
TYPICAL BENCH -
••••• -• •. • •
'1-: MAY REQUIRE SUBDRAIN IF SEEPAGE
' •••• CONDITIONS ARE INDICATED
, ....• • .
•. , •
- • GRADE- AFTER THE REMOVAL OF
TOPSOIL AND OTHER LOOSE SOILS
KEY CUT AND TOE DRAIN -
4" DIAMETER PERFORATED PIPE ENVELOPED
IN 1 cu. ft.. 3/4" DRAINAGE GRAVEL
NOT TO SCALE
NOTES:
1. SLOPE SHOULD. BE. STRIPPED QF TOPSOIL AND UNSUITABLE SOILS PRIOR TO PLACING ANY FILL.
2. , "BENCHES" SHOULD BE A MINIMUM OF 8 FEET WIDE. • •
3. "KEY" SHOULD BE 'MINIMUM. 2 FEET DEEP AND 10 FEET. WIDE, EXTENDING .THE FULL LENGTH OF
THE SLOPE FACE. • • .
4. FINAL SLOPE FACE SHOULD BE DENSIFIED BY COMPACTION.
'5. PLANT* OR HYDROSEED- SLOPE FACE TO REDUCE EROSION POTENTIAL. .
6. ALL STRUCTURAL FILL SHOULD BE COMPACTED TO 95% OF SOILS MAXIMUM DRY DENSITY PER
ASTM D-698 (STANDARD PROCTOR).
•
TERRA
ASSOCIATES
Geotechnical Consultants
GENERAL SLOPE FILL DETAIL
TUKWILA• PARKING LOT
TUKWILA, WASHINGTON
Proj.No. 4110
Date SEPT. 1998
Figure 3
•
12" MINIMUM WIDE
FREE—DRAINING GRAVEL
12"
•
SLOPE TO DRAIN
Oft—
/i. , /'S ,\
4" DIAMETER PVC
PERFORATED PIPE •
EXCAVATED SLOPE
(SEE REPORT FOR
APPROPRIATE
INCLINATIONS)
COMPACTED STRUCTURAL
BACKFILL
12" OVER THE PIPE
3" BELOW THE PIPE
NOT TO. SCALE
•
TERRA
" ASSOCIATES
Geotechnical Consultants
RETAINING WALL DRAINAGE DETAIL
TUKWILA PARKING LOT
TUKWILA, WASHINGTON ..
Proj. No. 4110
Date SEPT. 1998
Figure 4
• •
APPENDIX A
FIELD EXPLORATION AND LABORATORY TESTING
Tukwila Parking Lot
Tukwila, Washington
On August 17, 1998, we performed our field exploration at the site by excavating 9 test pits to depths ranging
from 5.0 to 10.5 feet below existing grades. The test pits were excavated with a rubber -tired backhoe.• The test
pit locations are shown on Figure 2. The test pit locations were approximately determined by pacing relative to
site boundaries, features, and adjacent test pits. Test pit elevations were interpreted from the provided conceptual
site plan. The Test Pit Logs are presented on Figures A-2 through A-6.
An engineer from our office maintained a log of each test pit as it was excavated, classified the soil conditions
encountered, and obtained representative soil samples. All soil samples were visually classified in accordance
with the Unified Soil Classification System shown on Figure A-1.
Representative soil samples obtained from the test pits were placed in sealed plastic bags and taken to our
laboratory for further examination and testing. . The moisture content of each sample was measured and is
reported on the Test Pit Logs. Grain size analyses were performed on three of the samples, the results of which
are presented on Figures A-7 and A-8.
Project No: T-4110
MAJOR DIVISIONS
LETTER
SYMBOL
TYPICAL DESCRIPTION
COARSE GRAINED SOILS
More than 50% material larger
than No. 200 sieve size
GRAVELS
More than
50% of coarse
fraction is
larger than No.
4 .sieve.
Clean
Gravels
(less than
5% fines)
GW
Well -graded gravels, gravel -sand mixtures, little or no
fines.
GP
Poorly graded gravels, gravel sand mixtures, little or
no fines.
Gravels
with fines
GM
Silty gravels, gravel -sand -silt mixtures, non plastic
fines.
GC
Clayey gravels, gravel -sand -clay mixtures, plastic fines.
SANDS
More than
50% of coarse
fraction is
smaller than
No. 4 sieve
Clean
• Sands
(less than
5% fines)
SW
Well -graded sands, gravelly sands, little or no fines.
SP
Poorly -graded sands or gravelly sands, little or no
fines.
Sands
with fines
SM
Silty sands, sand -silt mixtures, non -plastic fines.
SC
Clayey sands, sand -clay mixtures, plastic fines.
FINE GRAINED SOILS
More than 50% material
smaller than No. 200
sieve size
SILTS AND CLAYS
Liquid limit is less thaii 50%.
ML
Inorganic silts, rock flour, clayey silts with slight
plasticity.
CL
Inorganic clays of low to medium plasticity, (lean clay).
OL
Organic silts and organic clays of low plasticity.
SILTS AND CLAYS
Liquid limit is greater than 50%
MH
Inorganic silts, elastic.
CH
_
Inorganic clays of high plasticity, fat clays.
OH
Organic clays of high plasticity.
HIGHLY ORGANIC SOILS .
PT
Peat.
DEFINITION OF TERMS AND SYMBOLS
SAND or. GRAVEL
Standard Penetration
Density ' • Resistance in Blows/Foot
2" OUTSIDE DIAMETER SPLIT
I . SPOON SAMPLER
2.4" INSIDE DIAMETER RING SAMPLER
OR SHELBY TUBE SAMPLER
Y WATER LEVEL.(DATE)
Tr TORVANE READINGS, tsf
Pp PENETROMETER READING, tsf
DD DRY DENSITY, pounds per cubic foot
LL LIQUID LIMIT, percent
PI PLASTIC INDEX
N STANDARD PENETRATION, blows per foot
Very loose 0-4
Loose 4-10
Medium dense 10-30
. Dense 30-50.DATE)
Very dense >50
SILT or CLAY .
Standard Penetration.
Consistency Resistance in Blows/Foot
Very soft 0-2
Soft 2-4 .
Medium stiff 4=8
. Stiff 8-16
Very stiff 16-32
Hard >32
TERRA
ASSOCIATES
Geotechnical Consultants
UNIFIED SOIL CLASSIFICATION SYSTEM
TUKWILA PARKING LOT
TUKWILA, WASHINGTON •.
I.���\\\�
Proj. No. T-4110
Date SEPT. 1998
Figure A-1.
•
Logged by:. KPR
Date: 8/17/98
Depth
(ft.)
0
5
10
15
Test Pit No. TP -1
Soil Description
Approximate Elev. 127'
Moisture
Content
(0/0)
(8 inches Topsoil)
Light brown gravelly silty SAND with occasional cobbles, rare boulder,
clasts of sandstone, abundant roots to 2 feet, dense becoming very
dense, damp. Glacial Till. (SM)
7.3
8.7
8.6
Test pit terminated at 8.5 feet due to very difficult digging.
No groundwater or caving observed.
Loggedby: KPR
Date: 8/17/98
Depth
.(ft.)
0
5
Test Pit No. TP -2
Soil Description
Approximate Elev. 121.'
Moisture
Content
(0/0)
10-
15
Topsoil; brown organic silty very fine sand with abundant roots, damp.
(OLJSM)
Brown silty fine SAND with gravel, dense, damp. Glacial Till. (SM)
Yellow -tan mottled silty medium SAND, micaceous, dense, moist.
Renton Formation. (SM; completely weathered sandstone)
Increasingly difficult digging.'
10.4
8.3
17.8
Test pit terminated at 10.5 feet.
No groundwater or caving observed.
TERRA
ASSOCIATES
Geotechnical Consultants
TEST PIT LOGS
TUKWILA PARKING LOT
TUKWILA, WASHINGTON
Proj. No. • T-4110
Date SEPT. 1998
Figure A-2
Logged by: KPR
Date: 8/17/98
Depth
(ft.)
0
Test Pit No. -TP -3
Soil Description
Approximate Elev. 119'
Moisture
Content
(%)
Topsoil; with roots.
Brown silty fine SAND with gravel, dense, damp, with numerous boulders.
Glacial Till. (SM)
Yellow -tan mottled silty medium SAND, micaceous, dense, moist.
Renton Formation. (SM; completely weathered sandstone)
10-
15
Yellow -tan with orange oxidation, medium -grained SANDSTONE, highly
weathered, soft, moist. Renton Formation.
10.6
21.2
12.5
Test pit terminated at 10.5 feet due to difficult digging.
No groundwater or caving observed.
Logged by: KPR
Date: 8/17/98
. Depth
(ft.)
0
10.
15
Test Pit No. TP -4
Soil Description
Approximate Elev. 108'
Moisture
Content
(°/O)
Topsoil.
—Light brown silty very fine SAND with some gravel, roots, medium dense, damp.
Glacial Till. (SW
Yellow -tan to brown with orange oxidation silty medium SAND, dense,
moist. Renton Formation. (SM; completely weathered sandstone)
Yellow -tan with orange oxidation, medium -grained SANDSTONE, highly
weathered. soft. moist. Renton Formation.
Test pit terminated at 10.5 feet due to difficult digging.
No groundwater or caving observed.
8.3
43.7
10.2
TERRA
ASSOCIATES
Geotechnical Consultants
TEST PIT LOGS
TUKWILA PARKING LOT
TUKWILA, WASHINGTON
Proj. No. T-4110 I Date SEPT. 1998
Figure A-3
i
Logged by: KPR
Date: 8/17/98
Depth
(ft.)
0
10
15
Test Pit NofrP-5
Soil Description
Approximate Elev. 111'
Moisture
Content
(0/O)
FILL; brown -gray organic silty fine sand with gravel, loose, damp. (OUSM)
Tan to brown silty fine to medium SAND with gravel, cobbles, and
numerous 12 -inch to 24 -inch boulders, very dense, moist. Till -like. (SM)
17.1
9.7
Test pit terminated at 6 feet on large boulder.
No groundwater or caving observed.
Logged by: KPR
Date: 8/17/98
Depth
(ft.)
0
5
10
15
Test Pit No. TP -6
Soil Description
Approximate Elev. 105'
Moisture
Content
(opo)
(9 inches Topsoil) Brown silty very fine SAND with sandstone clasts, •
medium dense, damp. (SM)
Brown, fractured medium -grained SANDSTONE, sandy silt in matrix,
gravel to boulder -sized clasts, highly weathered, damp.
Renton Formation.
Becomes moderately weathered, hard, and fewer fractures.
8.0
7.9
Test pit terminated at 5 feet due to backhoe refusal.
No groundwater or caving observed.
TERRA
ASSOCIATES
Geotechnical Consultants
TEST PIT LOGS
TUKWILA PARKING LOT
TUKWILA, WASHINGTON
Proj. No. T-4110
Date SEPT. 19981 Figure A-4
Logged by: KPR
Date: 8/17/98
Depth
(ft.)
0
10
15
Test Pit No. P-7
Soil Description
Approximate Elev. 100'
Moisture
Content
(%1
Logged by: KPR
Date: 8/17/98
Depth
(ft.)
0
10
15
Test Pit No. TP -8
Soil. Description
Approximate Elev. 94'
Moisture
Content
(%)
Topsoil.
_
Light brown silty very fine SAND with some gravel, cobbles and
7.6
_
numerous 12 -inch to 30 -inch boulders, very large boulder in back
of test pit, very dense, moist. Glacial Till. (SM)
12.2
—
Becomes brown, moist and fine to medium -grained at 5 feet.
25.8
-
Difficult digging.
_
No groundwater seepage or caving observed. '.
-
•
23.6
_
Test pit terminated at 10 feet.
_
No groundwater or caving observed.
Logged by: KPR
Date: 8/17/98
Depth
(ft.)
0
10
15
Test Pit No. TP -8
Soil. Description
Approximate Elev. 94'
Moisture
Content
(%)
TERRA
ASSOCIATES
Geotechnical Consultants
TEST PIT LOGS
TUKWILA PARKING LOT
TUKWILA, WASHINGTON
Proj. No. T-4110
Date SEPT. 1998
Figure A-5
(6 inches Topsoil)
-
8.9
-
Light brown to brown silty fine to medium SAND with gravel, cobbles,
and 12 -inch to 30 -inch boulders, 4 to 5 -foot boulder in back of test pit,
very dense, damp to moist. Glacial Till: (SM)
12.2
17:1
_
Test pit terminated at 10 feet.
_
No groundwater seepage or caving observed. '.
TERRA
ASSOCIATES
Geotechnical Consultants
TEST PIT LOGS
TUKWILA PARKING LOT
TUKWILA, WASHINGTON
Proj. No. T-4110
Date SEPT. 1998
Figure A-5
•
Logged by: KPR
Date: 8/17/98
Depth
(ft.)
0
5
10
15
1
Test Pit No. TP -9
Soil Description
Approximate Elev. 84'
Moisture
Content
0/0
-
-
13 inches Topsoil.
Light brown silty fine SAND with some gravel, sandstone clasts, cobbles,
-
• and occasional boulders, very dense, moist. Glacial Till. (SM)
8.2
•
—
Becomes brown and fine to medium -grained at 5 feet.
11.0
-
. ' '
11.8
_
Test pit terminated at 10 feet.
_
No groundwater or caving observed.
_
.
TERRA
ASSOCIATES
Geotechnical Consultants
TEST PIT LOGS
TUKWILA PARKING LOT
TUKWILA, WASHINGTON ,
Proj. No. T-4110 Date SEPT. 1998 Figure A-6
+
0
0
to OZ (n
CD
100
90
80
-D
n 70
m.
,
-I 60
m
Z
7 50
40
G) 30
20
10
W N
0 0
SIEVE ANALYSIS
SIZE OF OPENING IN INCHES 1 . NUMBER OF MESH PER INCH, U.S. STANDARD
O
\\ \\\ \ \
N NJ -P. -P. CO N O -P.
N
O
O
0)
O
0
O
HYDROMETER ANALYSIS
00 0 0 0
O 0) -P. 41 N
GRAIN SIZE IN MM
0
o 0 .O 0 0
o 0 O o o
co TCA N
O
0
t 1 1
CO cn ' - W N
0 0 O 0 0 •.O
I t
1
I I
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— OD Q) .A W
11 t
GRAIN .SIZE IN MILLIMETERS
0 0 0 •
-A W N
000 00 b
O O O O O
co O -P. W N
10
20
m
•30 OT't
z
60 OD
70 m
80
90
100
0
O
COBBLES
COARSE 1 FINE
• GRAVEL
COARSE • 1 MEDIUM 1 FINE
SAND
Key
Test Pit
Number
Depth
(ft.)
USCS
Description
FINES
Moisture
Content (%)
LL
PL
•
0 .
TP -1
TP -2
2.0
6.0
SM
SM
gravelly silty SAND
silty SAND
o,
0
CD
N
P1
7-1
CD
CD
00
tO
co
Co
100
90
• 80
rn
n 70
m
z
60
rn
z
50
DJ
40
O 30
•
20
10
0
SIEVE ANALYSIS
SIZE OF OPENING IN INCHES 1 NUMBER OF MESH PER INCH, U.S. STANDARD
Cn
P W
C4 C.11�
N NJ -F. ' PCO N CO A -
•HYDROMETER ANALYSIS
GRAIN SIZE IN MM
N .
0,O O O O O 01
O O O
b o b b
0 0 O 0 0
CO 0) -P. W
b
O
b
IC
I 1
L
III
I L
I I
11
I 1 I I
1 1
1I I
O O . 0 0 O O O •
O•
O O O
COBBLES
CO•
COARSE J FINE
GRAVEL
W N •- 00 'co W N b b
co O)
GRAIN SIZE IN MILLIMETERS
COARSE 1 MEDIUM 1 FINE
SAND
-P. W N
bbo bb b
O O O O O
co Q) -P W N
FINES
0
10
20
2:1
rn •
30 rn
z
40 c)
O
D
Z7
50 U
m
60 CO
70 E
c)
80
90
100
O
O
Key
Test Pit
Number
Depth.
(ft.)
USCS
Description
Moisture
Content (%)
LL
PL
•
TP -8
5.0
SM
silty SAND with gravel
.,
TO BE COMPLETED BY APPLIC•
B. ENVIRONMENTAL ELEMENTS
1. Earth
a. General descriptionof the site (circle one): Flat,
rolling, hilly, steep slopes, mountainous, other
steep slopes
b. What isthe steepest slope on the site (approximate
percent slope)? 80
c. Whatgeneral types of soilsare
found
o . the site
te
(for example, clay, sand, gravel, peat,
you know the classification of agricultural soils,
specify them and note any prime farmland.
silty sand (Ur)
d. Are there surface indications or history of unstable
soils in the immediate vicinity? If so, describe.
no
e. Describe thepurpose, type,:.and approximate quanti-
ties of any filling or grading proposed: Indicate
source of fill. •
Grades may be raised in portions of the site
•for parking'lot construction_
f. Could erosion .occur as a result of clearing,
construction, or use? 'If so, generally describe.
Yes.- High erosion potential exists for.exposed
silty sands if not suitably prntPr-
g. About what percent of the site will be covered with
impervious surfaces after project construction (for
example, asphalt or buildings)?
Evaluation for
Agency Use Only
•
h. Proposed measures to reduce or control erosion, or
other impacts to the earth, if any:
Straw or securelv-anchored plastic sheeting.
2. Air
a. What 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.
b. Are there any off-site sources of emissions or odor
that may affect your proposal? If .so, generally
describe.
c. Proposed measures'to reduce or control emissions or
other impacts to air, if any:
3. Water
a. Surface:
.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_ names. If appropriate, state what
stream or river it flows into.
Evaluation for
Agency Use Only
CITY OPTUKWILA
Department of Community Development
6300 Southcenter Boulevard, Tukwila, WA 98188
Telephone: (206) 431-3670
•
RECEIVED
CITY OF TUKWILA
N O V 1 8 1998
PERMIT CENTER
SEPA APPLICATION CHECKLIST
FOR STAFF USE.ONLY
Planner::'.
Receipt.,Number.
File Number: 6 -go .:0492,1
Cross-reference files:;
Applicant notified: of ihcompletesapplication:'
`Applicant,notifie
of complete application
Notice of;application ,issue d:.:
A. NAME OF PROJECT/DEVELOPMENT:
C -Hall f a rk 404-- pivlsirn
C44/ Pro j ec+ ivo 95 -gGo 1
B. LOCATION OF PROJECT/DEVELOPMENT: (address and accessors parcel'number(s))
1544
•
12A -P' -c t_ No. 3511 D0o3a--o
Quarter: WE- Section: 2-3 Township: 2 --;Ai Range: 4-e-
(This information may be found on your tax statement)
C. PROJECT DESCRIPTION:
Con s-h"vcf- qD •- 5 j Ce pct rk; r►c Jot vi c Ivctri
5-ivrivt dvaivlae- /and crap; vmfterkoo
D. APPLICANT:
NAME: B 01) G ber50n
ADDRESS: 63&C Sou4-Ac Blvd.) S'vs 190
PHONE: 433 —6 (1 R ( d 1(031)
SIGNATURE:1g5'
DATE: •
CITY TUKWILA •
Department of Community Development
6300 Southcenter Boulevard, Tukwila, WA 98188
Telephone: (206) 431-3670
ENVIRONMENTAL REVIEW (SEPA) APPLICATION
SUBMITTAL REQUIREMENTS
To submit for SEPA review, provide the items listed above to the Planning Division at 6300
Southcenter Boulevard, Room 100.
17( 6 copies of the completed and signed environmental checklist.
You may use the City's pre-printed form or you may re -type the questions on your
computer. If you choose to re -type the form into your computer, be sure to do so
accurately. Mistakes or omissions will increase the review time.
17( 6 sets of the full size plans needed to clearly describe the proposed action.
One set of plans reduced to 8.5" x 11".
DECEIVED
171 Four copies of supporting studies. Cs of I s repo (4) CITY OF TUKWILA
N O V 1 8 1998
01 One copy of the checklist application.
11 One set of mailing labels for all properties 500' from the subject property. (See address
label worksheet.)
PERMIT CENTER
❑ $325 filing fee.
COMPLETING THE CHECKLIST
The checklist contains several pages of questions which you are asked to answer. It covers a
comprehensive set of topics. As a result, several of the questions may not apply to your project.
If a particular question does not apply, simply write N/A underneath. HOWEVER, be aware that
many questions apply despite appearing not to. Care needs to be taken in reading and answering
the questions to ensure the appropriate response is provided.
It is important that accurate and clear information be provided. You may not know all of the
answers. Answer each question to the best of your ability. If we find an answer to be insufficient,
the City may contact you to ask for more information.
Sometimes, after reviewing the checklist, the City will ask you provide additional studies or
information. Commonly requested information includes traffic analysis, site topography, soils
studies and tree surveys.
•
ENVIRONMENTAL CHECKLIST
CITY OF TUKWILA
PURPOSE OF CHECKLIST:
The State Environmental Policy Act (SEPA), Chapter 43.21C RCW, requires all govemmental
agencies to consider the environmental impacts of a proposal before making decisions. An
environmental 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.
Govemmental 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 not 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.
Some questions ask about govemmental regulations, such as zoning, shoreline, and landmark
designations. Answer these questions if you can. If you have problems, the govemmental
agencies can assist you.
The checklist questions apply to all parts of your proposal, even if you plan to do them over 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 NONPROJECT PROPOSALS:
Complete this checklist for nonproject proposals, even though questions may be answered
"does not apply". IN ADDITION, complete the SUPPLEMENTAL SHEET FOR NONPROJECT
ACTIONS (Part D).
For nonproject actions, the references in the checklist to the words "project", "applicant", and
"property or site" should be read as "proposal°, "proposer, and "affected geographic area,"
respectively.
CITY OF TUKWILA PARKING LOT PERMIT
11. Give brief, complete description of your proposal, including 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 to repeat those answers
on this page. Section E requires a complete description of the objectives and alternatives
of your proposal and should not be summarized here.
CONSTRUCT A 90 -SPACE PARKING LOT ON A PARCEL ADJACENT TO, AND NORTH OF, TUKWILA
CITY HALL. APPROXIMATELY 1.25 ACRES OF THE APPROXIMATELY 3.2 ACRE SITE WILL BE
PAVED. ACCESS FOR 70 OF THE PARKING SPACES WILL BE PROVIDED OFF 65TH AVENUE
SOUTH AND FROM THE EXISTING CITY HALL PARKING LOT. 20 SPACES WILL BE ALLOCATED TO
XEROX CORPORATION AND WILL BE ACCESSED ONLY FROM THE EXISTING XEROX PARKING LOT.
ILLUMINATION WILL BE INSTALLED FOR SECURITY AND SAFETY LIGHTING. A STORM DETENTION
POND WILL BE CONSTRUCTED TO PROVIDE STORM WATER CONTROL FOR QUALITY AND.
QUANTITY.
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 to duplicate maps or detailed plans
submitted with any permit applications related to this checklist.
THE PROPOSED PROJECT IS IMMEDIATELY NORTH OF TUKWILA CITY HALL, XEROX
CORPORATION AND THE KING COUNTY HOUSING AUTHORITY IN THE 15400 BLOCK OF 65TH
AVENUE SOUTH IN TUKWILA, WASHINGTON. THE PARCEL NUMBER IS 359700-0320 AND THE
PARCEL IS LOCATED IN SECTION 23, TOWNSHIP 23 NORTH, RANGE 4 EAST, W.M., IN KING
COUNTY, WASHINGTON. THE LEGAL DESCRIPTION OF THE SITE IS ATTACHED AS APPENDIX B. A
VICINITY MAP IS INCLUDED AS APPENDIX C. A SITE PLAN SHOWING THE PROPOSED PROJECT
AND SITE TOPOGRAPHY IS INCLUDED WITH THIS CHECKLIST AS APPENDIX D.
13. Does the proposal lie within an area designated on the City's Comprehensive
Land Use Policy Plan Map as environmentally sensitive?
YES. THE AREA HAS BEEN MAPPED AS A "CLASS 3 LANDSLIDE HAZARD" AREA BY THE CITY OF
TUKWILA. A GEOTECHNICAL REPORT BY TERRA ASSOCIATES, INC. STATES THAT, BASED ON
DETAILED SITE INVESTIGATION AND SUBSURFACE EXPLORATIONS, "IT IS OUR OPINION THAT THE
SITE IS NOT A LANDSLIDE HAZARD AREA."
B. ENVIRONMENTAL ELEMENTS
1. Earth
a. General description of the site (underline one): Flat, rolling, hilly,
steep slopes, mountainous, other.
STEEP SLOPES
• •
b. What is the steepest slope on the site (approximate percent
slope)?
material.
N/A
4) Will the proposal require surface water withdrawals or
diversions? Give general description, purpose, and
approximate quantities if known.
NO.
5) Does the proposal lie within a 100 -year floodplain? If so,
note location on the site plan.
NO.
6) Does the proposal involve any discharges of waste
materials to surface waters? If so, describe the type of waste
and anticipated volume of discharge.
NO.
b. Ground:
1) Will groundwater be withdrawn, or will water be
discharged to groundwater? Give general description,
purpose, and approximate quantities if known.
NO.
2) Describe waste material that will be discharged into the
ground from septic tanks or other sources, if any (for example:
Domestic sewage; industrial, containing the following
chemicals . . .; 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.
NONE.
c. Water Runoff (including storm water):
1) Describe the source of runoff (including storm water) and
method of collection and disposal, if any (include quantities, if
known). Where will this water flow? Will this water flow into
other waters? If so, describe.
STORM WATER WILL BE COLLECTED FROM IMPERVIOUS SURFACES WITH
THE USE OF CATCH BASINS AND PIPED TO A WET POND. WATER WILL BE
DISCHARGED FROM THE WET POND TO THE CITY STORMWATER
DRAINAGE SYSTEM.
2) Could waste materials enter ground or surface waters? If
so, generally describe.
YES. STANDARD ROAD AND AUTOMOTIVE POLLUTANTS FOUND IN STORM
WATER SYSTEMS COLLECTED ON THE SURFACE OF THE PARKING LOT
WILL ENTER THE STORM SYSTEM. SOME TREATMENT/SETTLING WILL
OCCUR IN THE WET POND.
APPROXIMATELY THE WEST 100 FEET OF THE SITE WILL BE LEFT
UNDISTURBED. THIS AREA CONTAINS EXISTING TREES, SHRUBS AND
GROUNDCOVER THAT WILL ACT AS THE BUFFER FOR THE RESIDENTIAL
IPROPERTIES TO THE WEST.
5. Animals
a. Underline 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, SONGBIRDS, other CROWS.
chickadees
mammals: deer, bear, elk, beaver, other SQUIRRELS
fish: bass, salmon, trout, herring, shellfish, other.
b. List any threatened or endangered species known to be on or
near the site.
NONE KNOWN.
C. Is the site part of a migration route? If so, explain.
UNKNOWN.
d. Proposed measures to preserve or enhance wildlife, if any:
LANDSCAPE IMPROVEMENTS.
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 WILL BE USED FOR PARKING LOT LIGHTING.
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:
NONE.
7. Environmental Health
a. Are there any environmental health hazards, including exposure
to toxic chemicals, risk of fire and explosion, spill, or hazardous
waste, that could occur as a result of this proposal? If so,
describe.
NO.
1) Describe special emergency services that might be
required.
NONE.
2) Proposed measures to reduce or control environmental
health hazards, if any:
NONE.
b. Noise:
1) What types of noise exist in the area which may affect
your project (for example: traffic, equipment, operation,
other)?
NONE.
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 what hours noise would come from the site.
LOW-LEVEL TRAFFIC NOISE ASSOCIATED WITH CARS IN A PARKING LOT WOULD BE
PRESENT, GENERALLY DURING WORKING HOURS OF 7 AM TO 6 PM.
3) Proposed measures to reduce or control noise impacts, if any:
NONE.
8. Land and Shoreline Use
a. What is the current use of the site and adjacent properties?
SITE IS VACANT COMMERCIAL. NEIGHBORING PROPERTIES ARE CITY HALL, OFFICE
BUILDINGS, CONDOMINIUMS, A CITY PARK AND SINGLE FAMILY RESIDENCES.
b. Has the site been used for agriculture? If so, describe.
ONLY RESIDENTIAL GARDENING AND FRUIT TREES.
c. Describe any structures on the site.
REMNANTS OF AN OLD BUILDING FOUNDATION WERE DISCOVERED ON THE SITE.
d. Will any structures be demolished? If so, what?
THE OLD FOUNDATION WILL BE REMOVED.
e. What is the current zoning classification of the site?
"O" OFFICE PARK.
f. What is the current comprehensive plan designation of the site?
O -OFFICE.
g. If applicable, what is the current shoreline master program
designation of the site?
OUTSIDE SHORELINE ZONE.
h. Has any part of the site been classified as an "environmentally
sensitive" area? If so, specify.
YES. THE AREA HAS BEEN MAPPED AS A "CLASS 3 LANDSLIDE HAZARD"
AREA BY THE CITY OF TUKWILA. A GEOTECHNICAL REPORT BY TERRA
ASSOCIATES, INC. STATES THAT, BASED ON DETAILED SITE INVESTIGATION
AND SUBSURFACE EXPLORATIONS, "IT IS OUR OPINION THAT THE SITE IS
NOT A LANDSLIDE HAZARD AREA."
i. Approximately how many people would reside or work in the
completed project?
NONE. PARKING WOULD BE PROVIDED FOR 90 PASSENGER VEHICLES.
j. Approximately how many people would the completed project
displace?
NONE.
k. Proposed measures to avoid or reduce displacement impacts, if
any:
NONE.
1. Proposed measures to ensure the proposal is compatible with
existing and projected land uses and plans, if any:
FOLLOWING GUIDELINES FOR DESIGN REVIEW, AS REQUIRED BY RE -ZONE COVENANT.
9. Housing
a. Approximately how many units would be provided, if any?
Indicate whether high, middle, or low income housing.
N/A
b. Approximately how many units, if any, would be eliminated?
Indicate whether high, middle, or low-income housing.
N/A
. •
' . •
12. Recreation
' a. What designated and informal recreational opportunities are in
the immediate vicinity?
TUKWILA PARK IS LOCATED TO THE EAST ACROSS 65TH AVENUE SOUTH. HAZELNUT PARK
IS LOCATED TO THE NORTH AT APPROXIMATELY SOUTH 147TH STREET AND 59TH AVENUE
SOUTH. FOSTER GOLF COURSE IS LOCATED TO THE NORTH ALONG INTERURBAN AVENUE.
' FORT DENT PARK IS LOCATED TO THE NORTHEAST, ACROSS THE GREEN RIVER. THE GREEN
RIVER TRAIL RUNS ALONG THE BANKS OF THE GREEN RIVER NEARBY. SOUTHCENTER MALL
UES TO THE SOUTH ACROSS INTERSTATE 405.
b. Would the proposed project displace any existing recreational
uses? If so, describe.
NO.
c. Proposed measures to reduce or control impacts on recreation,
' including recreation opportunities to be provided by the project or
applicant, if any:
NO.
13. Historic and Cultural Preservation
a. Are there any places or objects listed on, or proposed for,
national, state, or local preservation registers known to be on or
' next to the site? If so, generally describe.
UNKNOWN.
b. Generally describe any landmarks or evidence of historic,
archaeological, scientific, or cultural importance known to be on
or next to the site.
NONE.
' c. Proposed measures to reduce or control impacts, if any:
NONE.
14. Transportation
a. Identify public streets and highways serving the site, and describe
proposed access to the existing street system. Show on site
plans, if any.
' ACCESS WILL BE PROVIDED DIRECTLY OFF 65TH AVENUE SOUTH. ADDITIONAL SITE ACCESS
WILL BE THROUGH THE EXISTING TUKWILA CITY HALL PARKING LOT.
b. Is site currently served by public transit? If not, what is the
approximate distance to the nearest transit stop?
' YES.
' c. How many parking spaces would the completed project have?
How many would the project eliminate?
services, if any.
NONE.
16. Utilities
a. Underline utilities currently available at the site: electricity, natural
gpi, water, refuse service, telephone, sanitary sewer, 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.
ONSITE STORM DRAINAGE FACILITIES WILL BE CONSTRUCTED WHICH WILL CONNECT TO THE
OFFSITE STORM DRAINAGE FACILITIES.
C. SIGNATURE
The above answers are true and complete to the best of my knowledge. I understand that the
lead agency is relying on them to make its decision.
Signature:
Bob Giberson, P.E., Senior Engineer
Date Submitted:
• •
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 foregoing items of the
' Environmental Checklist. This information provides a general overall
perspective of the proposed action in the context of the
environmental information provided and the submitted plans,
' documents, supportive information, studies, etc.
1. What are the objective(s) of the proposal?
Appendix B
Legal Description of Proposed Parking Lot Site
Lot 17 of the Plat of Interurban Addition to Seattle;
LESS that portion lying northerly of the following described line:
Beginning at the Southwest corner of said Lot 17;
Thence North 210 feet;
Thence North 89°47'00" East to the westerly margin of 65th Avenue South,
all lying within Section 23, Township 23 North, Range 4 East, W.M. in King
County, Washington
F:\ 98\ 005\ DOCS\ SEPAPPA.DOC
•
Appendix C
Vicinity Map
0
APPENDIX A
Distribution List
RETAINING
WALL (UP)
flRUD(D
CGMC, OJ B
N. ols 9/13/09
I MOWS u/0/2000
UE3IC WORICS1 LE'11'77.
*ENGINEERING+ STREETS*WATER* Skw1sR* PARKS' BUILDING•.
CITY HALL PARKING LOT EXPANSION
CONTRACT,iNO. 95-BO01
Re No 98=005
WI 1"=30''
PLANT SCHEDULE.
SYMBOL PLANT NAME
PLANTING NOTES
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City of Tukwila
Public Works Dept.
City Hall
Parking Lot
Expansion ..
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R.W. Thorpe
& Associates, Inc.
710 Hogs Building •
/05 Sema Avenue
Seattle Washington 98104 .
Telephone: 209.924.8239
Fax 208.825.0390
E-Ma9: plannIng5rMa.mn . ..
,PRE GENNARY
iUBJF.CT.TO REVISION`
SECTION- PARKING STALL AND PLANTING ISLAND
Not to Scale.
SECTION- PLANTER ISLAND LANDSCAPING -
Not to Scale
RWTA JOB NO. 510798.
Preliminary
Planting:,
Plan
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