17-104396CITY OF
t Federal Way
October 23, 2017
1FILE
CITY HALL
33325 8th Avenue South
Federal Way, WA 98003-6325
(253) 835-7000
www. cityofiederalway.. com
Jim Ferrell, Mayor
Craig Deaver cdeaver@cesnwinc.cona
C.E.S. NW Inc.
310 29"' Street NE, Suite 101
Puyallup, WA 98372
Re: File #17-104396-00-PC, PREAPPLICATION CONFERENCE SUMMARY
Federal Way 2-Lot BLA, *No Site Address*, Federal Way
Dear Mr. Deaver:
Thank you for participating in the preapplication conference with the City of Federal Way's Development
Review Committee (DRC) held October 12, 2017. We hope that the information discussed at that meeting
was helpful in understanding the general requirements for your project as submitted.
This letter summarizes comments given to you at the meeting by the members of the DRC. The members
who reviewed your project and provided comments include staff from the City's Planning and Building
Divisions and Public Works Department, and representatives from Lakehaven Utility District and South
King Fire and Rescue. Some sections of the Federal Way Revised Code (FWRC) and relevant information
handouts are enclosed with this letter. Please be advised, this letter does not represent all applicable
codes. in preparing your formal application, please refer to the complete FWRC and other relevant codes
for all additional requirements that may apply to your project.
The key contact for your project is Becky Chapin, 253-835-2641, becky.chapin@cityoffederaIway.com.
For specific technical questions about your project, please contact the appropriate DRC representative as
listed below. Otherwise, any general questions about the preapplication and permitting process can be
referred to your key contact.
PROJECT DESCRIPTION
The applicant proposes to relocate the interior boundary line of two single family lots. The site contains
Geologically Hazardous Areas (GHA) and the boundary line adjustment will create a buildable area for
future development of a single family residence.
MAJOR ISSUES
Outlined below is a summary of the major issues of your project based on the plans and information
submitted for preapplication review. These issues can change due to modifications and revisions in the
plans. These major issues only represent comments that the DRC consider most significant to your project
and do not include the majority of the comments provided. The major issues section is only provided as a
means to highlight critical requirements or issues. Please be sure to read the entire department comments
made in the next section of this letter.
N,lr. Deaver
October 23. 2017
Page 2
+ Planning Division
• For properties within 50 ft. of a geologically hazardous area, the City will regUlrc a geotechnical
report, which will be peer reviewed by the City's consultant at the applicant's expense.
■ A stream identified in the City's Stream Inventory is located on the northern lot.
• The applicant must establish a shared ingress/egress easement for access to both lots.
• Public Works Development Services Division
There are no stormwater requirements for the BLA. Building permits will be required to meet
stormwater requirements in place at the time an application is made.
DEPARTMENT COMMENTS
Outlined below are the comments made by the representatives of each department present at the
preapplication conference. Each section should be read thoroughly. If you have questions, please contact
the representative listed for that section.
COMMUNITY DEVFLOPMENT—PLANNING DIVISION
Becky Chapin, 253-835-2641, becky.chapin@cityoffederalway.com
1. General Zoning Regulations — The subject property is located in the RS 15.0-1 unit/15,000 square
feet zoning district. Detached dwelling units are a permitted use subject to the regulations of FWRC
19.200.010.
i) Setbacks — 20 ft. front, 5 ft. rear. Please note: per FWRC 19.05.160, 'property lines ' are those
defined by a recorded vehicular easement, and accordingly, setbacks are measured from them.
ii) Maximum Height — 35 ft. above Average Building Elevation (ABE)
ill) Parking— 2 per dwelling unit
ivy Lot Coverage — 60%; for flag lots and lot coverage refer to FWRC 19.1 10.020.
v) Minimum Lot Size — 15,000 sq. ft.
Meeting Follow -zip: During the meeting the issue that the southern lot would not meet the minimum
lot size requirement was brought up. The issue was discussed with Planning Manager Robert 'Doc'
Hansen for clarification and whether there are any options moving forward. Per the enclosed Memo
prepared by Doc, for this particular proposal, the area of a vehicular access easement can be credited
in the calculation of minimum lot area, as proposed.
vi) Driveway Width — 20 ft. width limitation within required front yards and may not locate within
five-foot side yard setbacks pursuant to FWRC 19.130.240.
2. Application — The proposal requires a Boundary Line Adjustment (BLA). Such applications are
reviewed for conformity with FWRC Title 18 'Subdivisions', FWRC 18.10 `Boundary Line
Adjustments', and FWRC 18.55 'Design Criteria'. A boundary line adjustment is subject to an
administrative review conducted by city staff with a final decision made by the Director of
Community Development.
3. Public Notice — Boundary line adjustments do not require public notice.
17-104396-00-K Dw 11),76631
Mr. Deaver
October 23. 2017
Pate 3
4. Land Use Review Timeframes — The Planning Division wiI I notify the applicant of complete
application status within 28 days of submittal pursuant to FWRC 19.10.040. If determined complete,
staff will issue a Letter of Complete Application. If the application is determined to be incomplete,
staff within 14 days of the applicant submitting additional information will notify the applicant
whether the application is complete or whether additional information is necessary.
Per FWRC 18.10.050, the Director must issue a decision on the land use and design components
within 120 days from the date of a complete application. The review timeframe is suspended at any
time that additional information is requested by the City. The applicant must submit requested
information within 180 days of the review completion letter issued by the city, unless an extension is
granted in writing pursuant to FWRC 19.15.050(2).
5. Access Easement— In general, all lots shall be accessed by a public street right-of-way. In certain
cases, lots may be accessed by an ingress/egress and utilities easement or alley subject to the
requirements established in the City of Federal Way public works development standards. The BLA
must provide an ingress/egress and utilities easement to service proposed lots.
6. Critical Areas — Land use and building permit approvals are subject to the provisions of FWRC
Chapter 19.145 `Enviromnentally Critical Areas. 'As part of the boundary line adjustment
application include all relevant information in reference to environmentally critical areas on the
drawing or exhibits submitted per FWRC 18.10.030. FWRC 18.55.020 states all lots should have
ample dimensions to provide a regular -shaped building that meets required setbacks. A BLA
approval is not permitted to create environmentally constrained lots requiring special permits to
encroach into critical area buffers. In other words, lots should be "turn -key' at the time of a building
perm it application.
Geologically Hazardous Areas
Proposed BLA contains geologically hazardous areas including erosion hazard and landslide hazard
areas. Pursuant to FWRC 19.145.220, if the applicant proposes to develop or conduct land surface
modifications within 50 feet of the critical area, the applicant must submit a geotechnical report to
the City's satisfaction.
Prior to or concurrent with submitting an application for BLA the Geotechnical Engineering Study,
prepared by Earth Solutions NW, LLC, must be formally submitted to the City for third party peer
review at the applicant's expense. A scope of work and cost estimate will be prepared by the City's
consultant and provided to the applicant. Following acceptance and payment of the cost estimate, the
City's consultant would be authorized to begin their formal review of the report.
Strear»s
The northern lot contains a stream identified in the City of Federal Way Stream Inventory. Buffer
widths shall be measured outward on a horizontal plane fi-om the ordinary high water mark or top of
bank if the ordinary high water mark cannot be identified:
(a) Type F stream — 100 feet.
(b) Type Np stream — 50 feet.
(c) Type Ns stream — 35 feet.
17-1 W 3IM-OU-IT Doc I D.7b63 1
Mr. Deaver
October 23. 2017
Page 4
Meeting Follow-up: if the applicant does not want to delineate and rate the stream at this time, then
the max buffer width of 100 feet must be depicted on a separate exhibit document to make sure the
buildable area is outside the stream buffer. A note must be placed on the drawing that states the
stream has not been delineated as part of this BLA; a critical areas report may be required if any
alterations are being proposed within the stream or stream buffer.
7. Recording — The City will record the boundary line adjustment at the expense of the applicant with
the King County Recorder's office upon land use approval. Recording of a boundary line adjustment
shall comply with FWRC 18.30.300 and 18.30.280. Prior to recording the BLA, all surveying and
monumentation must be complete. Development Services and Planning Department will review the
drawings prior to recording; paper drawings are now accepted.
8. Application Fees — As development fees change annually, please contact the Pen -nit Center at 253-
835-2607 or permitcenter@cityoffederalway.com, for an updated fee list prior to submitting your
application for a Boundary Line Adjustment, Residential Building Permits.
PUBLIC WORKS —DEVELOPMENT SERVICES DIVISION
Ann Dower, 253-835-2732, ann.dower@cityoffederalway.com
Land Use Issues — Stormwater
Surface water runoff control and water quality treatment will be required per the regulations in place at
the time a building pen -nit application is received. Currently, those are outlined in the 2016 King County
Surface Water Design Manual (KCSWDM) and the City of Federal Way Addendum to the 2016
KCSWDM. Stormwater runoff from all impervious area (roof, driveway, etc.) must be controlled,
typically with Best Management Practices (BMP's). If no BMP's are feasible, a flow control facility may
be required.
PUBLIC WORKS —TRAFFIC DIVISION
Erik Preston, 253-835-2744, erik.preston@cityoffederalway.com
1. Documentation of an access easement connecting the subject properties to public right-of-way (SR
509) must be provided. For safety reasons, the City would prefer that the subject properties share
access to SR 509 with neighboring properties to consolidate the number of access points. If
consolidated access is not feasible, then stand-alone access will be acceptable in a way that
maximizes center -center spacing between the driveways.
2. The proposed on -site access easement must align with the documented offsite access easement(s) to
provide a continuous access path to the right-of-way.
3, Driveways that serve only residential uses may not be located closer than 25 feet to any street
intersection or driveway. Separation distances shall be measured from centerline to centerline of
roadways and driveways.
-17-1043/0-00-1'(' n,,c 11) 76631
Mr. Deaver
October 23. 2017
Page 5
COMMUNITY DEVELOPMENT — BUILDING DIVISION
Peter Lawrence, 253-835-2621, peter.lawrence@cityoffederalway.com
2015 International Residential Code w/ applicable State amendments
2015 UPC w/ applicable State amendments
2015 WSEC w/ applicable State amendments
A complete building permit application and residential checklist is required. (Application and checklists
may be obtained on our web site at www.cityoffederalway.com.) More information can be obtained by
calling the Permit Center at 253-835-2607 or email pen-nitceiiter@cityoffederalway.com.
cityoffederalway.com.
Energy code compliance worksheets are required to be completed and included with your permit
application.
A wet stamp and signature is required on all sheets of plans and on the cover page of any calculations
submitted.
The information provided is based on limited plans and information. The comments provided are
not intended to be a complete plan review and further comments are possible at the time of building
permit plan review.
LAKEHAVEN WATER AND SEWER DISTRICT
Brian Asbury, 253-946-5407, BAsbury@)lakehaven.org
These properties are within the water service area of City of Tacoma.
There are existing sewer system facilities on the south side of this portion of SW Dash Point Rd that are
accessible to/for the properties. Future development of the properties, regardless of the outcome of the land
use action, will require Lakehaven Sewer Certificate(s) of Availability, and subsequent sewer service
connections.
SOUTH KING FIRE AND RESCUE
Gordon Goodsell, 253-946-7241, Gordon.goodsell@southkingfire.org
Water Supply:
Fire Flow:
A Certificate of Water Availabilio; including a hydraudic fire flow model* shall be requested from the water
district and provided at the time of building permit application.
Fire Hydrants:
Existing hydrant location meets standard for construction on these lots.
*A hydraulic fire flolr model is required where proposed residence including garages and covered areas
exceed 3600 square feet.
17-104;96-00-K Disc ID.76631
Mr. Deaver
October 23.2017
Page 6
Emergency Access:
Fire apparatus access roads shall comply with all requirements of Fire Access Policy 10.006
litt J/soutlikiiiafii-e_or,, DoctimentCentei-/HomeNiew/24.
Fire apparatus access roads shall be installed and made serviceable prior to and during the time of
construction.
Fire Sprinkler System:
Fire sprinkler requirements, if any, will be determined at the time of building permit application.
CLOSING
This letter reflects the information provided at the preapplication meeting and is intended to assist you in
preparing plans and materials for formal application. We hope you found the comments useful to your
project. We have made every effort to identify major issues to eliminate surprises during the City's
review of the formal application. The completion of the preapplication process in the content of this letter
does not vest any future project application. Comments in this letter are only valid for one year as per
FWRC 19.40.070 (4).
As you know, this is a preliminary review only and does not take the place of the full review that will
follow submission of a formal application. Comments provided in this letter are based on preapplication
materials submitted.
Modifications and revisions to the project as presented for this preapplication may influence and modify
information regarding development requirements outlined above. In addition to this preapplication letter,
please examine the complete FWRC and other relevant codes carefully. Requirements that are found in
the codes that are not addressed in this letter are still required for your project.
If you have questions about an individual comment, please contact the appropriate department
representative noted above. Any general questions can be directed towards the key project contact, Becky
Chapin, 253-835-2641. We look forward to working with you.
Sincerely,
Becky Chapin
Associate Planner
enc: Master Land Use Application
Boundary Line Adjustment Checklist
Memo from Robert "Doe' Hansen
Lakehaven Map
c: Terry Wise. mailk%terrywisere.com
Ann Dower. Senior Engineering Plans Reviewer
Erik Preston. Senior Traffic Engineer
Brian Asbury- Lakehaven Water & Sewer District
GordN2 Goodsell. South King Fire & ReSCUC
17-1 OJ ;06-on-IT Doe I D 7663 I
MEMORANDUM
CITY OF
.���� `� Community Development Department
DATE: October 23, 2017
FROM: Robert `Doc' Hansen, Planning Manager
SUBJECT: File #17-104396-00-PC, Lot Area Calculation Clarification
Federal Way 2-Lot BLA, *No Site Address*, Federal Way
The applicant proposes to relocate the interior boundary line of two single family lots. The proposed
revised lot line will create a lot that is less than the minimum lot size requirement for the Single Family
Residential (RS 15.0) zone, 15,000 square feet per dwelling unit. Considering the particular circumstances
of the lots involved in the BLA request, it is determined that the boundary line adjustment can be
approved based upon the following findings and conclusions.
The lot is long and narrow with only one corner providing access to the two lots involved in the
boundary line adjustment proposal. Access to both lots will be provided by a north -south
easement and the western line of the easement can, and shall be, considered the front property
line. Even with a 20-foot setback from the front property line established by the easement, and a
5-foot setback from the rear property line, the site will accommodate area for reasonable
residential development.
2. One purpose for the boundary line adjustment request is to avoid the hazardous, steep slope
decline on the northern lot. With the south line of the north lot involved readjusted southerly, the
lot becomes safer with any development on the lot. Any development upon the lot will still
require geotechnical analysis prior to issuance of any building permit to ensure protection from
erosion, landslide or seismic hazard per FWRC 19.145.230 and 19.145.240.
FWRC 19.05.120 defines "Lot w-ea" as "the minimum lot area per dwelling unit based on the
underlying zone. For single-family lots, the area of a vehicular access easement, private tract,
flagpole, or access panhandle shall not be credited in calculation of ininimum lot area." This can
be interpreted in one of two ways. First, it can be interpreted that all easements will not be used
to evaluate minimum lot size. It can also be interpreted that the area of vehicular access easement
will not be considered part of the required minimum lot size for the lot being accessed. With this
particular proposal using the second interpretation, the access through the southern lot can be
counted toward the minimum lot size since it provides access to the northern lot, which cannot
use the access tract towards its evaluation of lot size.
4. The proposal can be changed so that the southern lot becomes a flag lot extending north to the
northern property boundary of the north lot in the proposal. This would meet the first
interpretation identified in item 3, above, but would create a lot that would minimize maintenance
of the entire lot, and could result in future lot line interpretation dispute. The creation of such lots,
while legal, does not meet the intent of the Code authorizing the BLA to improve lot orientation.
Given these special circumstances of this particular lot, staff finds it appropriate to approve the proposed
BLA; the south lot meeting the lot area requirement and the north lot minimizing the hazardous situation.
CITY OF -"
Federal Way
October 12, 2017
9:00 a.m.
Pre -application Conference Sign in Sheet
COMMUNITY DEVELOPMENT REVIEW COMMITTEE
Project Name: Federal Way 2 Parcels - BLA
Parcel #'s 112103-9013 & 9038
File Number: 17-104396-00-PC
City Hall
Hylebos Room
NAME
DEPARTMENT / DIVISION
TELEPHONE NUMBER
1.
kC
Cl
2.
W
ASS
3.
(/J vvtQi�f �c¢ S
253 -93S- Z73Z
4.t'Isnw
s.
V- 6 7Z¢33
6.
3i �l- ly �IJ
LA-k�EOAvW w S
7-S3 -
12
�✓��� ��7
8.
/
9.
10.
11.
12.
r
Earth
Solutions
NW uc
Geotechnical Engineering
Geology
Environmental Scientists
Construction Monitoring
` 3 `@17
r
CITY OF FEDERAL WAY
GEOTECHNICAL ENGINEERING STUDY • " -'�"
PROPOSED SHORT PLAT �•.T . ' :y '
43XX SOUTHWEST DASH POINT ROAD
WAY WASHINGTON
FEDERAL '�;_ •-_ -
�il��•- ��li
ES-5321
r
3
PREPARED FOR
BLUE HAWAII INN, LLC
c/o C.E.S. NW, INC.
July 25, 201
Bogdan S. , G.I.T.
Staff Geologist
Keven D. Hoffmann, P.E.
Senior Project Engineer
K I . Campbell, P.E.
Principal
GEOTECHNICAL ENGINEERING STUDY
PROPOSED SHORT PLAT
43XX SOUTHWEST DASH POINT ROAD
FEDERAL WAY, WASHINGTON
ES-5321
Earth Solutions NW, LLC
1806 —136t' Place Northeast, Suite 201
Bellevue, Washington 98005
Phone: 426 449-4704 1 Fax: 426-449-4711
www.earthsolutionsnw.com
— Geotechnical Engineering Report
�,
Geotechnical Services Are Performed for
Specific Purposes, Persons, and Projects
Geotechnical engineers structure their services to meet the specific needs of
their clients. A geotechnical engineering study conducted for a civil engi-
neer may not fulfill the needs of a construction contractor or even another
civil engineer. Because each geotechnical engineering study is unique, each
geotechnical engineering report is unique, prepared solelyfor the client. No
one except you should rely on your geotechnical engineering report without
first conferring with the geotechnical engineer who prepared it. And no one
— not even you —should apply the report for any purpose or project
except the one originally contemplated.
Read the Full Report
Serious problems have occurred because those relying on a geotechnical
engineering report did not read it all. Do not rely on an executive summary.
Do not read selected elements only.
A Geotechnical Engineering Report Is Based on
A Unique Set of Project -Specific Factors
Geotechnical engineers consider a number of unique, project -specific fac-
tors when establishing the scope of a study. Typical factors include: the
client's goals, objectives, and risk management preferences; the general
nature of the structure involved, its size, and configuration; the location of
the structure on the site; and other planned or existing site improvements,
such as access roads, parking lots, and underground utilities. Unless the
geotechnical engineer who conducted the study specifically indicates oth-
erwise, do not rely on a geotechnical engineering report that was:
• not prepared for you,
• not prepared for your project,
* not prepared for the specific site explored, or
+ completed before important project changes were made.
Typical changes that can erode the reliability of an existing geotechnical
engineering report include those that affect:
• the function of the proposed structure, as when it's changed from a
parking garage to an office building, or from a light industrial plant
to a refrigerated warehouse,
■ elevation, configuration, location, orientation, or weight of the
proposed structure,
• composition of the design team, or
• project ownership.
As a general rule, always inform your geotechnical engineer of project
changes--ven minor ones --and request an assessment of their impact.
Geotechnical engineers cannot accept responsibility or liability for problems
that occur because their reports do not consider developments of which
they were not informed.
Subsurface Conditions Can Change
A geotechnical engineering report is based on conditions that existed at
the time the study was performed. Do not rely on a geotechnical engineer-
ing reportwhose adequacy may have been affected by: the passage of
time; by man-made events, such as construction on or adjacent to the site;
or by natural events, such as floods, earthquakes, or groundwater fluctua-
tions. Always contact the geotechnical engineer before applying the report
to determine if it is still reliable. A minor amount of additional testing or
analysis could prevent major problems.
Most Geotechnical Findings Are Professional
Opinions
Site exploration identifies subsurface conditions only at those points where
subsurface tests are conducted or samples are taken. Geotechnical engi-
neers review field and laboratory data and then apply their professional
judgment to render an opinion about subsurface conditions throughout the
Bile. Actual subsurface conditions may differ —sometimes significantly —
from those indicated in your report. Retaining the geotechnical engineer
who developed your report to provide construction observation is the
most effective method of managing the risks associated with unanticipated
conditions.
A Report's Recommendations Are Not Final
Do not overrely on the construction recommendations included in your
report. Those recommendations are not final, because geolechnical engi-
neers develop them principally from judgment and opinion. Geotechnical
engineers can finalize their recommendations only by observing actual
subsurface conditions revealed during construction. The geolechnical
engineer who developed your report cannot assume responsibility or
liability for the report's recommendations if that engineer does not perform
construction observation.
A Geotechnical Engineering Report Is Subject to
Misinterpretation
Other design team members' misinterpretation of geotechnical engineering
reports has resuIled in costly problems. Lower that risk by having your geo-
technical engineer confer with appropriate members of the design team after
submitting the report. Also retain your geotechnical engineer to review perti-
nent elements of the design team's plans and specifications. Contractors can
also misinterpret a geotechnical engineering report. Reduce that risk by
having your geotechnical engineer participate in prebid and preconstruction
conferences, and by providing construction observation.
Do Not Redraw the Engineer's Logs
Geotechnical engineers prepare final boring and testing logs based upon
their interpretation of field logs and laboratory data. To prevent errors or
omissions, the logs included in a geotechnical engineering report should
neverbe redrawn for inclusion in architectural or other design drawings.
Only photographic or electronic reproduction is acceptable, but recognize
that separating logs from the report can elevate risk.
Give Contractors a Complete Report and
Guidance
Some owners and design professionals mistakenly believe they can make
contractors liable for unanticipated subsurface conditions by limiting what
they provide for bid preparation. To help prevent costly probtems, give con-
tractors the complete geotechnical engineering report, but preface it with a
clearly written letter of transmittal. In that letter, advise contractors that the
report was not prepared for purposes of bid development and that the
report's accuracy is limited; encourage them to confer with the geotechnical
engineer who prepared the report to modest fee may be required) and/or to
conduct additional study to obtain the specific types of information they
need or prefer. A prebid conference can also be valuable. Be sure contrac-
tors have sufficient time to perform additional study. Only then might you
be in a position to give contractors the best information available to you,
while requiring them to at least share some of the financial responsibilities
stemming from unanticipated conditions.
Read Responsibility Provisions Closely
Some clients, design professionals, and contractors do not recognize that
geotechnical engineering is far less exact than other engineering disci-
plines. This lack of understanding has created unrealistic expectations that
have led to disappointmei its, claims, and disputes. To help reduce the risk
of such outcomes, geotechnical engineers commonly include a variety of
explanatory provisions in their reports. Sometimes labeled "limitations"
many of these provisions indicate where geotechnical engineers' responsi-
bilities begin and end, to help others recognize their own responsibilities
and risks. Read these provisions closely. Ask questions. Your geolechnical
engineer should respond fully and frankly.
Geoenvironmental Concerns Are Not Covered
The equipment, techniques, and personnel used to perform a geoenviron-
mentai study differ significantly from those used to perform a geotechnical
study. For that reason, a geotechnical engineering report does not usually
relate any geoenvirorimental findings, conclusions, or recommendations;
e.g., about the likelihood of encountering underground storage tanks or
regulated contaminants. Unanticipatedenvironmental problems have led
to numerous project failures. If you have not yet obtained your own geoen-
vironmental information, ask your geotechnical consultant for risk man-
agement guidance. Do not rely on an environmentai report prepared for
someone else.
obtain Professional Assistance To Deal with Mold
Diverse strategies can be applied during building design, construction,
operation, and maintenance to prevent significant amounts of mold from
growing on indoor surfaces. To be effective, all such strategies should be
devised for the express purpose of mold prevention, inleg rated into a com-
prehensive plan, and executed with diligent oversight by a processional
mold prevention consultant. Because just a small amount of water or
moisture can lead to the development of severe mold infestations, a num-
ber of mold prevention strategies focus an keeping building surfaces dry.
While groundwater, water intiitration, and similar issues may have been
addressed as part of the geotechnical engineering study whose findings
are conveyed in -this report, the geotechnical engineer in charge of this
project is not a mold prevention consultant; none of the services per-
formed in connection with the geotechnical engineer's study
were designed or conducted for the purpose of mold preven-
tion. Proper implementation of the recommendations conveyed
in this report will not of itself he sufficient to prevent mold from
growing in or on the structure involved.
Rely, on Your ASFE-MemberGeotechncial
Engmeer for Additional Assistance
Membership in ASFFiThe Best People on Earth exposes geotechnical
engineers to a wide array of risk management techniques that can be of
genuine benefit €ar everyone involved with a construction project. Confer
with you ASFE-member geotechnical engineer far more information.
ASFE
The Elsa r6/rr*a �A foriR
8811 Colesville Road/Suite G106, Silver Spring, MD 20910
Telephone:3011565-2733 Facsimile:301/589-2017
e-mail: info@asfe.org www.asfe.org
Copyrlgh12004 by ASFE. Inc. Duplication. reproduction, or copylrig or this document, in whole Orin part, by any means whatsoever. is stricllyprohibited. except rvlth ASFE's
specific written permission. Excerpting, quoting, or otherwise extracting wording from this document is parmined only with the express. writren permission of ASFE, and only for
purposes of scholarly research or book taweW. Only members of ASFE may use this document as a complement to or as an element of a geolechnical engineering report Any other
firm, individual, or other entity that so uses this document without being an ASFE member could he committing negligent or intentional (fraadulear) misrapresentallon.
IGER06045,0M
July 25, 2017
ES-5321
Blue Hawaii Inn, LLC
c/o C.E.S. NW, Inc.
310 — 29th Street Northeast, Suite 101
Puyallup, Washington 98372
Attention: Ms. Rachel Mattock
Dear Ms. Mattock:
Earth
{ Solutions
NW«C
Earth Solutions NW LLC
Geotechnical Engineering
• ConstrUCLion Monitoring
• Environmental Science
Earth Solutions NW, LLC (ESNW) is pleased to present this report titled "Geotechnical
Engineering Study, Proposed Short Plat, 43XX Southwest Dash Point Road, Federal Way,
Washington". Based on the results of our investigation, the proposed residential development
is feasible from a geotechnical standpoint. Our study indicates the site is underlain primarily by
advance outwash and transitionary glacial till deposits. During our subsurface exploration
completed on June 28, 2017, groundwater seepage was not encountered at the test pit
locations. Nonetheless, it is our opinion the contractor should be prepared to discrete zones of
groundwater seepage during construction.
In our opinion, the proposed residential structures may be constructed on conventional
continuous and spread footing foundations bearing upon competent native soil, recompacted
native soil, or new structural fill. In general, competent native soil suitable for support of
foundations will likely be encountered within the upper two to three feet of existing grades.
Where loose or unsuitable soil conditions are exposed at foundation subgrade elevations,
compaction of soils to the specifications of structural fill, or overexcavation and replacement
with suitable structural fill, will be necessary.
At this time, given the predominance of relatively clean sands across the site, infiltration may be
feasible from a geotechnical standpoint. Final site designs and/or grading plans, however, may
affect infiltration feasibility. With respect to the existing topography, base elevations of
proposed infiltration facilities should be designed so that stormwater does not infiltrate either
into a geologically hazardous area (GHA) or onto adjacent properties. The in -situ density of the
native sands should also be considered, as dense soils typically have a reduced infiltration
capacity. ESNW can provide further evaluation of, and recommendations for, stormwater
infiltration design and related feasibility during the appropriate phase of design.
Based on our field observations and testing, we recommend a 15-foot buffer be incorporated
into the plans. The buffer should be measured from the top of the steep slope (see Plate 2 for
an approximate delineation). In addition, we recommend a five-foot structural buffer setback
feet be incorporated into final designs. The structural buffer setback should be measured from
the edge of the GHA buffer.
i,w5-'136th Place N.E., Suite 201 • Bellevue, ANA 98005 • (425) 449-4704 • FAX (425) 449-4711
Blue Hawaii Inn, LLC
c/o C.E.S. NW, Inc.
July 25, 2017
ES-5321
Executive Summary — Page 2
Pertinent geotechnical recommendations are provided in this study. We appreciate the
opportunity to be of service to you on this project. If you have questions regarding the content
of this geotechnical engineering study, please call.
Sincerely,
EARTH SOLUTIONS NW, LLC
Keven D. Ho mann, P.E.
Senior Project Engineer
Earth Solutions NW, LLC
Table of Contents
ES-5321
PAGE
INTRODUCTION...... ........................................
General..................................................................................... 1
Pro'ect Description ................................................................ 2
SITECONDITIONS............................................................................. 2
Surface..................................................................................... 2
Subsurface............................................................................... 3
Topsoiland Fill............................................................. 3
NativeSoil ....................... .............................................. 3
Geologic Setting ................................... 3
Groundwater............................................................................ 4
GEOLOGICALLY HAZARDOUS AREAS ASSESSMENT ................. 4
Erosion Hazard Area.— ........................................................... 4
Landslide Hazard Area ................................................... 5
Buffer and Setback Distances ................................................ 6
DISCUSSION AND RECOMMENDATIONS.................... ....................
6
....
6
General.... .............................................................................
Site Preparation and Earthwork .............................................
7
Temporary Erosion Control .........................................
7
Stripping........................................................................
7
Excavations and Slopes ...............................................
8
In -situ and Imported Soils ............................................
8
Subgrade Preparation ......................................
.........
9
Structural Fill .......................................
9
Foundations.............................................................................
9
10
SeismicDesign ........................................................................
10
Slab -on -Grade Floors.............................................................
RetainingWalls.......................................................................
11
11
Drainage...................................................................................
12
Infiltration Feasibility....................................................
Utility Support and Trench Backfill........................................
12
LIMITATIONS.............................................................................
Services
I........
13
13
Additional ................................................................
Earth Solutions NW, LLC
GRAPHICS
Plate 1
Plate 2
Plate 3
Plate 4
APPENDICES
Appendix A
Appendix B
Table of Contents
Continued
ES-5321
Vicinity Map
Test Pit Location Plan
Retaining Wall Drainage Detail
Footing Drain Detail
Subsurface Exploration
Test Pit Logs
Laboratory Test Results
Earth Solutions NW, LLC
GEOTECHNICAL ENGINEERING STUDY
PROPOSED SHORT PLAT
43XX SOUTHWEST DASH POINT ROAD
FEDERAL WAY, WASHINGTON
ES-5321
INTRODUCTION
General
This geotechnical engineering study (study) was prepared for the proposed residential
development to be constructed along the north side of Southwest Dash Point Road,
approximately 650 feet northeast of the intersection with 44th Avenue Southwest, in Federal
Way, Washington. The purpose of this study was to develop geotechnical recommendations
for the proposed prosect. The scope of services for completing this study included the following:
In Completing test pits for purposes of characterizing site soil conditions;
• Completing laboratory testing of soil samples collected at the test pit locations;
• Conducting engineering analyses, and;
■ Preparation of this report.
The following documents and maps were reviewed as part of preparing this study:
Civil Site Plans, prepared by C.E.S. NW, Inc., dated May 10, 2017;
• Geologic Map of the Tacoma 1:100,000-scale Quadrangle, Washington, prepared by J.
Eric Schuster et al., dated November 2015;
• Topographic Survey, prepared by O'Hare Land Surveying, dated May 18, 2011;
• City of Federal Way, Washington (City), Critical Areas Map, dated May 2016;
■ Chapter 19.145 of the Federal Way Revised Code (FWRC), and;
Web Soil Survey (WSS) online resource, maintained by the Natural Resources
Conservation Service (NRCS) under the United States Department of Agriculture
(USDA).
Earth Solutions NW, LLC
Blue Hawaii Inn, LLC
c/o C.E.S. NW, Inc.
July 25, 2017
Pro'ect Description
ES-5321
Page 2
We understand the site will be developed into a residential subdivision comprised of two single-
family residential lots and related infrastructure improvements. At the time of report
submission, specific grading, stormwater, and building load plans were not available for review;
however, based on our experience with similar developments, the proposed residential
structures will likely be two to three stories in height and constructed using relatively lightly
loaded wood framing supported on conventional foundations. Perimeter footing loads will likely
be about 1 to 2 kips per lineal foot (klf). Slab -on -grade loading is anticipated to be
approximately 150 pounds per square foot (psf).
We anticipate grade cuts and fills of about five to eight feet will be necessary to achieve the
majority of finish grade elevations. Retaining walls and/or rockeries may be incorporated into
final designs to accommodate grade transitions, where necessary. Stormwater will likely be
managed by conventional methods, with infiltration used to the extent feasible.
If the above design assumptions are incorrect or change, ESNW should be contacted to review
the recommendations provided in this report. ESNW should review final designs to confirm that
appropriate geotechnical recommendations have been incorporated into the plans.
SITE CONDITIONS
Surface
The subject site is located on the north side of Southwest Dash Point Road, about 650 feet
northeast of the intersection with 44th Avenue Southwest, in Federal Way, Washington. The
approximate location of the subject property is illustrated on the Vicinity Map (Plate 1). The
rectangular property is comprised of two adjoined tax parcels (King County Parcel Nos.
112103-9013 and -9038) totaling approximately one acre.
The property is bordered to the north, west, and east by single-family residences and
associated open space, and to the south by Southwest Dash Point Road. The site is currently
undeveloped, and vegetation consists primarily of mature trees and a relatively thick brush
understory. Grades descend from south to north, with approximately 80 feet of elevation
change across the property (average gradients of 25 to 35 percent). The Dumas Creek flows
through the northern half of the property prior to discharging into Puget Sound. No
development is proposed north of Dumas Creek, and a 60-foot stream buffer has been
incorporated into the plans.
Earth Solutions NW, LLC
Blue Hawaii Inn, LLC
c/o C.E.S. NW, Inc.
July 25, 2017
Subsurface
ES-5321
Page 3
A representative of ESNW observed, logged, and sampled five test pits, excavated at
accessible site locations, on June 28, 2017 using a mini trackhoe and operator retained by our
firm. The test pits were completed for the purposes of assessing soil and groundwater
conditions. The approximate locations of the test pits are illustrated on the Test Pit Location
Plan (Plate 2). Please refer to the test pit logs provided in Appendix A for a more detailed
description of subsurface conditions. Representative samples collected at the test pit locations
were analyzed in accordance with both Unified Soil Classification System (USCS) and United
States Department of Agriculture (USDA) methods and procedures.
Topsoil and Fill
In general, topsoil was encountered within the upper 8 to 12 inches at the test pit locations.
The topsoil was characterized by light brown color, the presence of fine organic material, and
small root intrusions. Based on our field observations, we estimate topsoil will be encountered
with an average thickness of 8 to 10 inches across the site.
Fill was not encountered at test pit locations during our fieldwork. However, areas of fill may
exist in proximity to improvements adjacent to the site. Where encountered during construction,
ESNW can evaluate fill deposits (as necessary).
Native Soil
Underlying topsoil, native soils were encountered primarily as medium dense to dense, poorly
graded sand with or without silt (USCS: SP-SM and SP) and dense to very dense, silty sand
with gravel (SM). Soil relative density generally increased with depth. In general, native soils
were observed primarily in a medium dense to dense and moist condition, extending to the
maximum exploration depth of approximately 12 feet below the existing ground surface (bgs).
Geologic Setting
The referenced geologic map resource identifies the site as underlain predominately by
advance outwash deposits (Qga). As described on the geologic map resource, advance
outwash deposits are characterized as compact sand and pebbles deposited by advancing
glaciers.
The referenced WSS resource indicates the site is underlain primarily by Alderwood gravelly
sandy loam (Map Unit Symbol: AgC) in the northern half of the property and Alderwood and
Kitsap soils (Map Unit Symbol: AkF) in the southern half of the property. The Alderwood series
consists of soils formed in glacial drift and outwash. The Alderwood and Kitsap series consists
of soils formed in glacial till plains.
Based on our field observations, on -site soils generally correlate with a transitionary geologic
setting between advance outwash and glacial till. It is noted that glacial till is mapped to the
south and west of the subject site.
Earth Solutions NW, LLC
Blue Hawaii Inn, LLC
c/o C.E.S. NW, Inc.
July 25, 2017
Groundwater
ES-5321
Page 4
During our subsurface exploration completed on June 28, 2017, groundwater seepage was not
observed at the test pit locations. In our opinion, while significant groundwater seeps are not
likely to be encountered during construction, perched groundwater seepage should be
anticipated within site excavations. Seepage rates and elevations fluctuate depending on many
factors, including precipitation duration and intensity, the time of year, and soil conditions. In
general, groundwater flow rates are higher during the wetter, winter months.
GEOLOGICALLY HAZARDOUS AREAS ASSESSMENT
Based on our review of FWRC Chapter 19.05.070 and the referenced City critical areas map,
the site features the following geologically hazardous areas (GHAs): erosion hazard and
landslide hazard. A review of the identified GHAs is provided in this assessment.
Erosion Hazard Area
The FWRC defines erosion hazard areas as "those areas defined by the USDA NRCS as
having a moderate to severe, or severe to very severe, rill and inter -rill erosion hazard due to
natural agents such as wind, rain, splash, frost action, or stream flow." Such areas include the
following soil groups when occurring on slopes of 15 percent of greater: Alderwood-Kitsap
(AkF), Alderwood gravelly sandy loam (AgD), Kitsap silt loam (KpD), Everett (EvD), and
Indianola (InD).
As outlined in the Geologic Setting section of this study, Alderwood and Kitsap series soils are
mapped within the site. These soils are typically associated with moderate to high erosion
hazard potential, especially during the wetter, winter months. Provided appropriate temporary
and permanent erosion and sediment control (ESC) measures are incorporated into final
designs, however, erosion potential can be adequately mitigated both during and after
construction. Site -specific ESC measures are typically prepared by the project civil engineer
during the appropriate phase of design. No evidence of either shallow or deep-seated slope
instability was observed during our June 2017 site reconnaissance.
Earth Solutions NW, LLC
Blue Hawaii Inn, LLC
c/o C.E.S. NW, Inc.
July 25, 2017
Landslide Hazard Area
ES-5321
Page 5
The FWRC defines landslide hazard areas as "those areas potentially subject to episodic
downslope movement of a mass of soil or rock" including, but not limited to, the following areas:
a) Any area with a combination of:
i) Slopes greater than 15 percent;
ii) Permeable sediment, predominantly sand and gravel overlying relatively
impermeable sediment or bedrock, and;
iii) Springs or groundwater seepage.
b) Any area that has shown movement during the Holocene epoch, or that is underlain by
mass wastage debris of that epoch.
c) Any area potentially unstable as a result of rapid stream incision, stream bank erosion, or
undercutting by wave action.
d) Any area located in a ravine or on an active alluvial fan, presently or potentially subject to
inundation by debris flows or flooding.
e) Those areas mapped as Class U (unstable), UOS (unstable old slides), and URS
(unstable recent slides) by the Department of Ecology's Coastal Zone Atlas.
f) Areas designated as quaternary slumps, earthflows, mudflows, lahars, or landslides on
maps published by the United State Geological Survey or Washington State Department
of Natural Resources.
g) Slopes having gradients greater than 80 percent, subject to rockfall during seismic
shaking.
h) Any area with a slope of 40 percent or steeper and with a vertical relief of 10 or more
feet, except areas composed of consolidated rock.
Based on our review and field observations, it is our opinion the site, specifically the steep
slope, is appropriately identified within a landslide hazard area. This opinion is based primarily
on a portion of the steep slope possessing a gradient of 40-or-more percent over at least 10
feet of vertical relief.
Earth Solutions NW, LLC
Blue Hawaii Inn, LLC
c/o C.E.S. NW, Inc.
July 25, 2017
ES-5321
Page 6
Our site reconnaissance and review of local geologic mapping indicates that the steep slope is
comprised of advanced outwash transitioning to consolidated glacial till -like deposits. It is
common for lateral migration of groundwater along the transition between weathered and
unweathered (dense) soils to cause surficial slumps. During our June 2017 site
reconnaissance, however, no evidence of recent slope instability was observed. Based on our
review and field observations, it is our opinion that the slope exhibits good slope stability
characteristics.
Buffer and Setback Distances
Based on our field observations, it is our opinion a reduced buffer (from the standard buffer of
50 feet) is appropriate from a geotechnical standpoint, This opinion is based on the presence
of competent, medium dense to dense native deposits on the steep slope and the absence of
indications that shallow and deep-seated slumps and/or failures occur (or have previously
occurred) on the slope.
From a geotechnical standpoint, we recommend a 15-foot buffer be incorporated into the plans.
The buffer should be measured from the top of the steep slope, which is defined as the distinct
topographic break that separates slopes inclined at less than 40 percent from slopes inclined at
40 percent or more (see Plate 2 for an approximate delineation). In addition, we recommend a
five-foot structural buffer setback feet be incorporated into final designs. The structural buffer
setback should be measured from the edge of the GHA buffer. A total structural setback of 20
feet, as measured from the delineated steep slope break, should be incorporated into the plans.
DISCUSSION AND RECOMMENDATIONS
General
Based on the results of our investigation, construction of the proposed residential lots is feasible
from a geotechnical standpoint. The primary geotechnical considerations associated with the
proposed development include foundation support, slab -on -grade subgrade support, and the
suitability of using on -site soils as structural fill.
In our opinion, the proposed residential structures may be constructed on conventional
continuous and spread footing foundations bearing upon competent native soil, recompacted
native soil, or new structural fill. In general, competent native soil suitable for support of
foundations will likely be encountered within the upper two to three feet of existing grades.
Where loose or unsuitable soil conditions are exposed at foundation subgrade elevations,
compaction of soils to the specifications of structural fill, or overexcavation and replacement
with suitable structural fill, will be necessary.
Earth Solutions NW, LLC
Blue Hawaii Inn, LLC
c/o C.E.S. NW, Inc.
July 25, 2017
ES-5321
Page 7
At this time, given the predominance of relatively clean sands across the site, infiltration may be
feasible from a geotechnical standpoint. Final site designs and/or grading plans, however, may
affect infiltration feasibility. With respect to the existing topography, base elevations of
proposed infiltration facilities should be designed so that stormwater does not infiltrate either
into a GHA or onto adjacent properties. The in -situ density of the native sands should also be
considered, as dense soils typically have a reduced infiltration capacity. ESNW can provide
further evaluation of, and recommendations for, stormwater infiltration design and related
feasibility during the appropriate phase of design.
This study has been prepared for the exclusive Use of Blue Hawaii Inn, LLC and their
representatives. No warranty, expressed or implied, is made. This study has been prepared in
a manner consistent with the level of care and skill ordinarily exercised by other members of the
profession currently practicing under similar conditions in this area.
Site Preparation and Earthwork
Initial site preparation activities will consist of installing temporary erosion control measures,
establishing grading limits, and performing clearing and site stripping. Subsequent earthwork
activities will involve mass site grading and related infrastructure improvements.
Temporary Erosion Control
Prior to the installation of either initial or final pavement sections, temporary construction
entrances and drive lanes, consisting of at least six inches of quarry spalls, should be
considered to both minimize off -site soil tracking and provide a stable access entrance surface.
Geotextile fabric may also be considered underlying the quarry spalls for greater stability of the
temporary construction entrance. Erosion control measures should consist of silt fencing
placed around the site perimeter. Soil stockpiles should be covered or otherwise protected to
reduce soil erosion. In no circumstance should soil stockpiles be placed on or near steep slope
areas. Temporary approaches for controlling surface water runoff should be established prior
to beginning earthwork activities. Additional Best Management Practices (BMPs), as specified
by the project civil engineer and indicated on the plans, should be incorporated into
construction activities.
Stripping
Topsoil was encountered generally within the upper 8 to 12 inches of existing grades at the test
pit locations. ESNW should be retained to observe site stripping activities at the time of
construction so that the degree of required stripping may be assessed. Over -stripping should
be avoided, as it is unnecessary and may result in increased project development costs.
Topsoil and organic -rich soil is neither suitable for foundation support nor for use as structural
fill. Topsoil and organic -rich soil may be used in non-structural areas, if desired.
Earth Solutions NW, LLC
Blue Hawaii Inn, LLC
c/o C.E.S. NW, Inc.
July 25, 2017
Excavations and Slopes
ES-5321
Page 8
Excavation activities are likely to expose both loose to medium dense, upper outwash and
dense glacial deposits at depth. Provided appropriate methods of sloping and shoring (as
necessary) for the excavations are incorporated into the design and construction, overall
stability of site excavations is anticipated to be good. Based on the soil conditions observed at
the test pit locations, the following allowable temporary slope inclinations, as a function of
horizontal to vertical (H:V) inclination, may be used. The applicable Federal Occupation Safety
and Health Administration (OSHA) and Washington Industrial Safety and Health Act (WISHA)
soil classifications are also provided:
Loose and medium dense soils 1.5H:1V (Type C)
• Areas containing groundwater seepage 1.5H:1 V (Type C)
Dense soils 1 H:1 V (Type B)
If desired during construction, steeper temporary slope inclinations within undisturbed, dense to
very dense native deposits may be feasible based on the soil and groundwater conditions
exposed within the excavations. Steeper inclinations may be considered, and must be
subsequently evaluated, by ESNW at the time of construction.
Permanent slopes should be planted with vegetation to enhance stability and to minimize
erosion, and should maintain a gradient of 2HAV or flatter. The presence of perched
groundwater may cause localized sloughing of temporary slopes due to excess seepage forces.
An ESNW representative should observe temporary and permanent slopes to confirm the slope
inclinations are suitable for the exposed soil conditions and to provide additional excavation and
slope recommendations as necessary. If the recommended temporary slope inclinations
cannot be achieved, temporary shoring may be necessary to support excavations.
In -situ and Imported Soils
From a geotechnical standpoint, on -site soils may be suitable for use as structural fill. On -site
soils are moisture sensitive, and successful use of on -site soils as structural fill will largely be
dictated by the moisture content at the time of placement and compaction. Remedial
measures, such as soil aeration and/or cement treatment (where approved by the local
jurisdiction or utility district), may be necessary as part of site grading and earthwork activities.
If the on -site soils cannot be successfully compacted, the use of an imported soil may be
necessary. In our opinion, a contingency should be provided in the project budget for export of
soil that cannot be successfully compacted as structural fill if grading activities take place during
periods of extended rainfall activity. Soils with fines contents greater than 5 percent typically
degrade rapidly when exposed to periods of rainfall.
Earth Solutions NW, LLC
Blue Hawaii Inn, LLC
c/o C.E.S. NW, Inc.
July 25, 2017
ES-5321
Page 9
Imported soil intended for use as structural fill should consist of a well -graded, granular soil with
a moisture content that is at (or slightly above) the optimum level. During wet weather
conditions, imported soil intended for use as structural fill should consist of a well -graded,
granular soil with a fines content of 5 percent or less (where the fines content is defined as the
percent passing the Number 200 sieve, based on the minus three -quarter -inch fraction).
Subgrade Preparation
Foundation and slab subgrade surfaces should be compacted in -situ to a minimum depth of
one foot below the design subgrade elevation. Uniform compaction of the foundation and slab
subgrade areas will establish a relatively consistent subgrade condition below the foundation
and slab elements. ESNW should observe the compacted subgrade areas prior to placing
formwork. Supplementary recommendations for subgrade improvement may be provided at the
time of construction; such recommendations would likely include further mechanical compaction
effort and/or overexcavation and replacement with suitable structural fill.
Structural Fill
Structural fill is defined as compacted soil placed in foundation, slab -on -grade, and roadway
areas. Fill placed to construct permanent slopes and throughout retaining wall and utility trench
backfill areas is considered structural fill as well. Soils placed in structural areas should be
placed in loose lifts of 12 inches or less and compacted to a relative compaction of 90 percent,
based on the laboratory maximum dry density as determined by the Modified Proctor Method
(ASTM D1557). For soil placed in utility trenches underlying structural areas, compaction
requirements are dictated by the local city, county, or utility district, and are typically specified to
a relative compaction of at least 95 percent. The upper 12 inches of pavement subgrade areas
should also be compacted to a relative compaction of at least 95 percent.
Foundations
In our opinion, the proposed residential structures may be constructed on conventional
continuous and spread footing foundations bearing upon competent native soil, recompacted
native soil, or new structural fill. In general, competent native soil suitable for support of
foundations will likely be encountered within the upper two to three feet of existing grades.
Where loose or unsuitable soil conditions are exposed at foundation subgrade elevations,
compaction of soils to the specifications of structural fill, or overexcavation and replacement
with suitable structural fill, will be necessary. Provided the foundations will be supported as
prescribed, the following parameters may be used for design:
Allowable soil bearing capacity 2,500 psf
• Passive earth pressure 300 pcf (equivalent fluid)
■ Coefficient of friction 0.40
Earth Solutions NW, LLC
Blue Hawaii Inn, LLC
c/o C.E.S. NW, Inc.
July 25, 2017
ES-5321
Page 10
A one-third increase in the allowable soil bearing capacity may be assumed for short-term wind
and seismic loading conditions. The above passive pressure and friction values include a
factor -of -safety of 1.5. With structural loading as expected, total settlement in the range of one
inch and differential settlement of about one-half inch is anticipated. The majority of settlement
should occur during construction, as dead loads are applied.
Seismic Design
The 2015 International Building Code recognizes the American Society of Civil Engineers
(ASCE) for seismic site class definitions. In accordance with Table 20.3-1 of the ASCE
Minimum Design Loads for Buildings and Other Structures manual, Site Class D should be
used for design.
The referenced liquefaction susceptibility map indicates the subject site maintains "low to very
low" liquefaction susceptibility. Liquefaction is a phenomenon where saturated or loose soils
suddenly lose internal strength and behave as a fluid. This behavior is in response to
increased pore water pressures resulting from an earthquake or other intense ground shaking.
In our opinion, site susceptibility to liquefaction may be considered low. The relatively
consistent densities of the native soils and the absence of a uniformly established, shallow
groundwater table were the primary bases for this consideration.
Slab -on -Grade Floors
Slab -on -grade floors for the proposed residential structures should be supported on well -
compacted, firm and unyielding subgrades. Where feasible, native soils exposed at the slab -
on -grade subgrade levels can likely be compacted in -situ to the specifications of structural fill.
Unstable or yielding subgrade areas should be recompacted, or overexcavated and replaced
with suitable structural fill, prior to slab construction.
A capillary break consisting of a minimum of four inches of free -draining crushed rock or gravel
should be placed below the slabs. The free -draining material should have a fines content of 5
percent or less (where the fines content is defined as the percent passing the Number 200
sieve, based on the minus three -quarter -inch fraction). In areas where slab moisture is
undesirable, installation of vapor barriers below the slabs should be considered. If a vapor
barrier is to be utilized, it should be a material specifically intended for use as a vapor barrier
and should be installed per the specifications of the manufacturer.
Earth Solutions NW, LLC
Blue Hawaii Inn, LLC
c/o C.E.S. NW, Inc.
July 25, 2017
Retaining Walls
ES-5321
Page 11
Retaining walls must be designed to resist earth pressures and applicable surcharge loads.
The following parameters may be used for design:
Y Active earth pressure (yielding condition)
At -rest earth pressure (restrained condition)
Traffic surcharge (passenger vehicles)
Passive earth pressure
• Coefficient of friction
• Seismic surcharge
" Where appficable
Where H equals the retained height (in feet)
35 pcf (equivalent fluid)
55 pcf
70 psf (rectangular distribution)'
300 pcf (equivalent fluid)
0.40
6H psf**
The above design parameters are based on a level backfill condition and level grade at the wall
toe. Revised design values will be necessary if sloping grades are to be used above or below
retaining walls. Additional surcharge loading from adjacent foundations, sloped backfill, or
other relevant loads should be included in the retaining wall design.
Retaining walls should be backfilled with free -draining material that extends along the height of
the wall and a distance of at least 18 inches behind the wall. The upper 12 inches of the wall
backfill may consist of a less permeable soil, if desired. A perforated drainpipe should be
placed along the base of the wall and connected to an approved discharge location. A typical
retaining wall drainage detail is provided on Plate 3. If drainage is not provided, hydrostatic
pressures should be included in the wall design.
Draina e
Discrete zones of perched groundwater seepage should be anticipated in site excavations
depending on the time of year grading operations take place, particularly within deeper
excavations for lots and utilities. Temporary measures to control surface water runoff and
groundwater during construction would likely involve interceptor trenches and sumps. ESNW
should be consulted during preliminary grading to identify areas of seepage and to provide
recommendations to reduce the potential for instability related to seepage effects.
Finish grades must be designed to direct surface drain water away from structures and slopes.
Water must not be allowed to pond adjacent to structures or slopes. In our opinion, foundation
drains should be installed along building perimeter footings. A typical foundation drain detail is
provided on Plate 4.
Earth Solutions NW, LLC
Blue Hawaii Inn, LLC
c/o C.E.S. NW, Inc.
July 25, 2017
Infiltration Feasibility
ES-5321
Page 12
As indicated in the Subsurface section of this study, native soils encountered during our
fieldwork were characterized primarily as advance outwash (relatively clean sands) atop glacial
till -like deposits (dense silty sand). According to the results of USDA textural analyses
performed on representative soil samples, the relatively clean sands and silty sands further
classify primarily as slightly gravelly sand and slightly gravelly sandy loam, respectively.
Irrespective of gravel content, the fines contents of the native slightly gravelly sand and the
slightly gravelly sandy loam were about 4 to 6 percent and 38 to 40 percent, respectively, at the
tested locations.
At this time, given the predominance of relatively clean sands across the site, infiltration may be
feasible from a geotechnical standpoint. Final site designs and/or grading plans, however, may
affect infiltration feasibility. With respect to the existing topography, base elevations of
proposed infiltration facilities should be designed s❑ that stormwater does not infiltrate either
into a GHA or onto adjacent properties. The in -situ density of the native sands should also be
considered, as dense soils typically have a reduced infiltration capacity. Ultimately, from a
geotechnical standpoint, conventional methods of stormwater management, e.g., dispersion,
detention, and connecting to an existing stormwater collections system, may prove more
practicable.
At the appropriate stage of design, ESNW should provide further evaluation of, and
recommendations for, stormwater infiltration design and related feasibility. In -situ testing should
be completed to both definitively assess the feasibility for site infiltration and provide design
infiltration rates, as needed. Additionally, should infiltration be pursued, ESNW should be
retained to perform supplementary subsurface exploration during the wet season to observe
groundwater flow volumes and elevations (which may affect infiltration feasibility).
Utility Support and Trench Backfill
In our opinion, on -site soils will generally be suitable for support of utilities. Remedial measures
may be necessary in some areas to provide support for utilities, such as ❑verexcavation and
replacement with structural till and/or placement of geotextile fabric. Groundwater seepage
may be encountered within utility excavations, and caving of trench walls may occur where
groundwater is encountered. Depending on the time of year and conditions encountered,
dewatering, as well as temporary trench shoring, may be necessary during utility excavation
and installation.
On -site soils may be suitable for use as structural backfill throughout utility trench excavations
provided the soil is at (or slightly above) the optimum moisture content at the time of placement
and compaction. Moisture conditioning of the soils may be necessary at some locations prior to
use as structural fill. Each section of the utility lines must be adequately supported in the
bedding material. Utility trench backfill should be placed and compacted to the specifications of
structural fill as previously detailed in this report, or to the applicable specifications of the City or
other responsible jurisdiction or agency.
Earth Solutions NW, LLC
Blue Hawaii Inn, LLC
c/o C.E.S. NW, Inc.
July 25, 2017
LIMITATIONS
ES-5321
Page 13
The recommendations and conclusions provided in this study are professional opinions
consistent with the level of care and skill that is typical of other members in the profession
currently practicing under similar conditions in this area. A warranty is neither expressed nor
implied. Variations in the soil and groundwater conditions observed at the test pit locations may
exist and may not become evident until construction. ESNW should reevaluate the conclusions
provided in this study if variations are encountered.
Additional Services
ESNW should have an opportunity to review final project plans with respect to the geotechnical
recommendations provided in this report. ESNW should also be retained to provide testing and
consultation services during construction.
Earth Solutions NW, LLC
-IF'
_
Z t 41•y., x '4+ � s
PAAIIr TWIN
q ES
ds _ w * _:i !'i ':1G': ^ !�'tr r''•- 4 :r, -'_ Y Yc'�Y': � -
1[!S - 1 •'v 4+ ,` �} x 7• :�'f tl t - •+ ' " -�kj it i1 �1 Vr
5 041-
� t { :r Aelf•
'rt. Y V r. rr to r■
* :�e1n t01v SKr ..SW x 320ry
r #r
i� .W F/ak" RTA.- FdRti' •#! 51 {~:� i c Ck73 GQI� 1
+r �'rnu«r
s ,•� ` v g� y 41�-
CY4Y9 Y • �� .S s7
'
Jr }1
ht.�"
r ►' „ `�
e5y -1. Ci I,R „JI%
Si y p1
Y—Y! tswl th+Re Hnxis �e ps + r
r '+Srkkin
E!">iW ��jei1 �? tii J4• ..F 'JI[a r'r,*{,. CY L. •� {,,�� t '���
Fj�
r SBRi] 4 an. •, dtlttsrtl v r�rt - 46
OIL- N.
'!F MLA
wr
t- .� ' I x _ s� � • y� �
v
I1+. r-
�yx, r;;r;�rr►
rts•Silr�-
fr'es
ua.�+Yo - 7�,qk C•.:, ..,� � � �. � .tile ;7 .0 -�
iE r }S6t� +r P_--S�S'M � `���t` t, Ea .� iJl$• ;�.S, it *�
d0k
Sin' nr4Ar
H i E ilrOAf `i S St i l; :t!� s
_ sl tic
J.
Reference:
King County, Washington
Map 744
By The Thomas Guide
Rand McNally
32nd Edition
NOTE: This plate may contain areas of color. ESN1N cannot be
responsible for any subsequent misinterpretation of the information
resulting from black & white reproductions of this plate.
J
Earth
Solutions
NW LLc
S,
i
Vicinity Map
Dash Point 2-Lot
Federal Way, Washington
Drwn. MRS I Date 07/10/2017 Proj. No. 5321
Checked BST Date July 2017 Plate 1
i
i
i
IF
I
LEGEND
TP-1 Approximate Location of
— ■ — ESNW Test Pit, Proj. No.
J i ES-5321, June 2017
Subject Site
i
Existing Building
I 1 ! Dumas Creek
TP-2� _ I — i (Delineated by Others)
i TP-3
' Approximate Top of
— — — 40% Slope
I �—
I I TP-4 House
t I I
1 TP-51 {T
I
House �
l
I
1 �
1
\\
NOTE: The graphics shown on this plate are not intended for design
purposes a preclse scale measurements, but only to illustrate the
approximate test locations retative to the approximate locations of
existing and ! or proposed site features. The information illustrated
is largely based on data provided by the client at the time of our
study. ESNW cannot be responsible for subsequent design changes
or interpretation of the data by others.
0
1 "=100'
Earth
Solutions
NW ruc
NORTH
50 100 200
—1 Scale in Feet
Test Pit Location Plan
Dash Point 2-Lot
Federal Way, Washington
NOTE: This plate may contain areas of color. ESNW cannot be Drwn. MRS Date 07/21 /2017 Proj. No. 5321
responsible for any subsequent misinterpretation of the information
resulting from black & white reproductions of this plate. Checked BST Date July 2017 Plate 2
r
NOTES:
18" Min.
o 0 O o o o 0 O VO O
0o 0 o do o .0o0
0
0 o O O0 0 00 0 0 000 o
Oo 0 00000 o 0 0 000
0 0 o
a Poo o0 o�,,0 00
0 0'. aoo qo 0 o0 8 0
oo O O o
o O o
o 0000-
oo c
0 oo o oo 0 oo oo 0
0o 00 o 0o 0000°o c o
00 000 0 00 o Oo o�
0 0 0 o o 0
00 0 O o 0 00 000 oO o
O q q `0 o O 00 Q 0 CY
o
08`oo�000 �0
a o 0 o c 0 oo o 0 0 00 0
O o
o o o 0 00
0opo oo V 0 o 0o
0 o 0
o 00 0 0 0 0
0 000 0 0 00 0 0 00 0& � v
o g o 0 O000 00 .r0wo� 0
0 0 0 o 0 a7ia-rfd•J�
• Free Draining Backfill should consist
of soil having less than 5 percent fines.
Percent passing #4 should be 25 to
75 percent.
■ Sheet Drain may be feasible in lieu
of Free Draining Backfill, per ESNW
recommendations.
• Drain Pipe should consist of perforated,
rigid PVC Pipe surrounded with 1"
Drain Rock.
LEGEND:
0 �o p Free Draining Structural Backfill
_ � o
M
1 inch Drain Rock
Structural
Fill
Perforated Drain Pipe
(Surround In Drain Rock)
SCHEMATIC ONLY - NOT TO SCALE
NOT A CONSTRUCTION DRAWING
Earth
Solutions
NW L�c
RETAINING WALL DRAINAGE DETAIL
Dash Point 2-Lot
Federal Way, Washington
Drwn. MRS
Date 07/11/2017
Proj. No.
5321
Checked BST
Date July 2017
Plate
3
Perforated Rigid Drain Pipe
(Surround with 1" Rock)
NOTES:
* Do NOT tie roof downspouts
to Footing Drain.
• Surface Seal to consist of
12" of less permeable, suitable
soil. Slope away from building.
SCHEMATIC ONLY - NOT TO SCALE
NOT A CONSTRUCTION DRAWING
LEGEND:
Surface Seal; native soil or
other low permeability material.
ti•1•t•ti•
r•r•r•r•
t•4•t•'L•
1" Drain Rock
FOOTING DRAIN DETAIL
Dash Point 2-Lot
Federal Way, Washington
Drwn. MRS
Date 07/11/2017
Proj. No. 5321
Checked BST
Date July 2017
Plate 4
Appendix A
Subsurface Exploration
Test Pit Logs
ES-5321
Subsurface conditions at the subject site were explored on June 28, 2017 by excavating five
test pits using a mini trackhoe and operator retained by our firm. The approximate locations of
the test pits are illustrated on Plate 2 of this study. The test pit logs are provided in this
Appendix. The test pits were advanced to a maximum depth of approximately 12 feet bgs.
The final logs represent the interpretations of the field logs and the results of laboratory
analyses. The stratification lines on the logs represent the approximate boundaries between
soil types. In actuality, the transitions may be more gradual.
Earth Solutions NW, LLC
Earth Solutions N V1✓LLC
SOIL CLASSIFICATION CHART
SYMBOLS
TYPICAL
MAJOR DIVISIONS
DESCRIPTIONS
GRAPH
I LETTER
CLEAN
' �� ��
GW
WELL -GRADED GRAVELS, GRAVEL -
SAND MIXTURES, LITTLE OR NO
GRAVEL
GRAVELS
�,
FNES
AND
°lVa ayOv
POORLY -GRADED GRAVELS,
GRAVELLY
SOILS
(LITTLE OR NO FINES)
0 0Qo D
GP
GRAVEL- SAND MIXTURES, LITTLE
C3,0
OR NO FINES
COARSE
°
GRAINED
GRAVELS WITH
GM
SILTY GRAVELS, GRAVEL - SAND -
SOILS
MORE THAN 50%
FINES
D
SILT MIXTURES
OF COARSE
a
FRACTION
RETAINED ON NO.
4 SIEVE
(APPRECIABLE
G`+
CLAYEY GRAVELS, GRAVEL - SAND -
AMOUNT OF FINES)
CLAY MIXTURES
CLEAN SANDS
SW
WELL -GRADED SANDS, GRAVELLY
MORE THAN 50%
SAND
SANDS, LITTLE OR NO FINES
OF MATERIAL IS
AND
SP
POORLY -GRADED SANDS,
GRAVELLY SAND, LITTLE OR NO
LARGER THAN
NO.200 SIEVE
SANDY
SOILS
SIZE
LITTLE OR NO FINES)
([><
FINES
SANDS WITH
SM
SILTY SANDS, SAND - SILT
MORE THAN 50%
FINES
MIXTURES
OF COARSE
FRACTION
PASSING ON NO.
4 SIEVE
(APPRECIABLE
S`+
CLAYEY SANDS, SAND -CLAY
AMOUNT OF FINES)
MIXTURES
INORGANIC SILTS AND VERY FINE
ML
SANDS, ROCK FLOUR, SILTY OR
CLAYEY FINE SANDS OR CLAYEY
SILTS WITH SLIGHT PLASTICITY
SILTS
INORGANIC CLAYS OF LOW TO
FINE
LIQUID LIMIT
CL
MEDIUM PLASTICITY, GRAVELLY
GRAINED
CLAYSAND LESS THAN 50
CLAYS, LEAN CLAYS CLAYS,CLAYS, SANDY SILTY
SOILS
OL
ORGANIC SILTS AND ORGANIC
—
SILTY CLAYS OF LOW PLASTICITY
MORE THAN 50%
INORGANIC SILTS, MICACEOUS OR
OF MATERIAL IS
MH
DIATOMACEOUS FINE SAND OR
SMALLER THAN
SILTY SOILS
NO.200 SIEVE
CH
INORGANIC CLAYS OF HIGH
SIZE
SILTS
LIQUID LIMIT
AND
GREATER THAN50
PLASTICITY
CLAYS
OH
CLAYS OF MEDIUM TO
HIGH PLASTICITY, ORGANIC SILTS
HIGH
HIGHLY ORGANIC SOILS
PT
PEAT, HUMUS, SWAMP SOILS WITH
HIGH ORGANIC CONTENTS
DUAL SYMBOLS are used to indicate borderline soil classifications.
The discussion in the text of this report is necessary for a proper understanding of the nature
of the material presented in the attached logs.
Earth Solutions N"---�
1805 - 136th Plac, c., Suite 201
Bellevue, Washington 98005
Telephone: 425-449-4704
Fax: 425-449-4711
CLIENT Blue Hawaii Inn. LLC c/o C.F.S. NW. Inc_
PROJECT NUMBER ES-5321
DATE STARTED 6/28/17 u COMPLETED 6/28117
EXCAVATION CONTRACTOR NW Excavating _—
EXCAVATION METHOD
LOGGED BY BST CHECKED BY KDH
NOTES Depth of Topsoil & Sod 12": ivy_
TEST PIT NUMBER TP-1
PAGE 1 OF 1
PROJECT NAME Dash Point 2-Lot
PROJECT LOCATION Federal Wa Washington
GROUND ELEVATION 114 ft TEST PIT SIZE
GROUND WATER LEVELS:
AT TIME OF EXCAVATION —
AT END OF EXCAVATION —
AFTER EXCAVATION ---
w
�W
U
_
a
w Co
TESTS
a 0
MATERIAL DESCRIPTION
uj �-
a 2
vi
qo_ -1
Q z
c7
co
0
Light brown TOPSOIL
TPSL,,
, ,
-roots to 2'
Tan poorly graded SAND, medium dense, damp (Advance outwash)
MC = 3.80%
SP
-trace gravel
MC = 43.10% r 1 44.0
Fines = 33.50% Tan silty SAND with gravel, dense, moist (Glacial till)
[USDA Classification: slightly gravelly fine sandy LOAM]
-becomes gray, increasing grain size
SM
-weakly cemented
MC = 19.70% -iron oxide staining
iF
110.01
-becomes very dense 105.5
MC = 12.80% _ ss_ _
Test pit terminated at 8.5 feet below existing grade. No groundwater encountered during
excavation. No caving observed.
Bottom of test pit at 8.5 feet.
J
J
yL
}
1
L
33
Earth Solutions N' TEST PIT NUMBER TP-2
1805 - 136th Plact. .-c., Suite 201 PAGE 1 OF 1
Bellevue, Washington 98005
Telephone: 425-449-4704
qWM Fax: 425-449-4711
CLIENT Blue Hawaii Inn. LLC c(o C.E.S. NW, Inc_ PROJECT NAME _Dash Point 2-Lot
PROJECT NUMBER ES-5321 PROJECT LOCATION Federal Way. _
DATE STARTED 6/28/17 COMPLETED 6/28/17 ^ GROUND ELEVATION 118 ft TEST PIT SIZE
EXCAVATION CONTRACTOR NW E)mvating GROUND WATER LEVELS:
EXCAVATION METHOD AT TIME OF EXCAVATION
LOGGED BY BST CHECKED BY KDH AT END OF EXCAVATION
NOTES Depth. of To soil & Sod 10": brambles AFTER EXCAVATION
w
a- �
Co
TESTS
O
M z
C9
0
!Tps�
,
MC = 11.60%
MATERIAL DESCRIPTION
Light brown TOPSOIL
-roots to 2'
Tan poorly graded SAND, medium dense, damp (Advance outwash)
-trace gravel
117
SP
MC = 7.10%
Fines = 4.50% [USDA Classification: slightly gravelly SAND]
5 -becomes dense, moist
-becomes gray, increasing grain size
MC = 16.00% _ &0 112
Fines = 38.20% Tan silty SAND with gravel, dense, moist (Glacial till)
[USDA Classification: slightly gravelly sandy LOAM]
SM -iron oxide staining
-weakly cemented
B 5 -becomes gray, very dense ius
MC = 13.30% Test pit terminated at 8.5 feet below existing grade. No groundwater encountered during
excavation. No caving observed.
r
Bottom of test pit at 8.5 feet_
Earth Solutions N1
1805 - 136th Place . cL, Suite 201
Bellevue, Washington 98005
Telephone: 425-449-4704
Fax: 425-449-4711
CLIENT Blue Hawaii Injl LLC cio C.E.S. NW, lnc.
PROJECT NUMBER E8-5321
DATE STARTED 6128117
COMPLETED 6/28/17
EXCAVATION CONTRACTOR
MM EXMVabn
EXCAVATION METHOD
_.
LOGGED BY BST
CHECKED BY KDH
NOTES Depth of Topsoil & Sod 12�ferns _
w
}Cr
U
a
�
TESTS
vUi
O
ov
2z
ca
TEST PIT NUMBER TP-3
PAGE 1 OF 1
PROJECT NAME Dash Point 2-Lot
PROJECT LOCATION Federal Way, Washington
GROUND ELEVATION 126 ft TEST PIT SIZE
GROUND WATER LEVELS:
AT TIME OF EXCAVATION
AT END OF EXCAVATION =
AFTER EXCAVATION
Light brown TOPSOIL
MATERIAL DESCRIPTION
r Ole -roots to 1.5'
1.0
�j Tan poorly graded SAND with silt, medium dense, moist (Advance outwash)
SP-
MC = 4.20%
Fines = 5.40% SM [USDA Classification: slightly gravelly SAND]
4.5
Tan poorly graded SAND, dense, moist
5 MC = 6.40%
SP
-becomes gray, increasing grain size
1i) MC = 9.10%�_J_�u.uTest
pit terminated at 10.0 feet below existing grade. No groundwater encountered
during excavation. No caving observed.
Bottom of test pit at 10.0 feet.
Earth Solutions N' } TEST PIT NUMBER TP-4
1805 - 136th Place ...E., Suite 201 PAGE 1 OF 1
MWBellevue, Washington 98005
Telephone: 425-449-4704
Fax: 425-449-4711
CLIENT Blue Hawaii InnLLC cio C.E.S. NW. Inc. PROJECT NAME Dash Point 2-Lot _
PROJECT NUMBER ES-=1 PROJECT LOCATION Federal Way, Washington
DATE STARTED 6/28/17 COMPLETED fi/28/17 GROUND ELEVATION 128 it TEST PIT SIZE
EXCAVATION CONTRACTOR NW Excavating GROUND WATER LEVELS:
EXCAVATION METHOD _ AT TIME OF EXCAVATION
LOGGED BY BST _ CHECKED BY KDH AT END OF EXCAVATION
NOTES Depth of TO ail & Sod 8": fems AFTER EXCAVATION -
w
}
66
a iK
W 0°
TESTS
U
a
MATERIAL DESCRIPTION
o..
2z
C7
a
S
..
Light brown TOPSOIL
D.B
Tan poorly graded SAND with silt, medium dense, damp (Advance outwash)
-roots to 1.5'
-trace gravel
-
MC = 4.30%
SP-
SM
MC = 10.80% Tan poorly graded SAND, dense, moist
Fines = 4.40% [USDA Classification: slightly gravelly SAND]
FV
SP
-becomes gray, increasing grain size
MC = 6.20% Test pit terminated at 12.0 feet below existing grade. No groundwater encountered
during excavation. No caving observed _17:� Bottom of test pit at 12.0 feet.
CY
116.0
Earth Solutions NI
1805 - 136th Place m.E., Suite 201
MWBellevue, Washington 98005
Telephone: 425-449-4704
Fax: 425-449-4711
CLIENT Blue Hawaii Inn LLC rl0 C.E.S_ NW. Inc.
PROJECT NUMBER ES-5321
DATE STARTED 6/28/17 COMPLETED 6/28/17
EXCAVATION CONTRACTOR NW Excavation
EXCAVATION METHOD
LOGGED BY BST CHECKED BY KDH _
NOTES Depth of Taasoil & Sod 8": fems
w
o-
v
a x
TESTS
C3
O
2 z
D
(9
a
TEST PIT NUMBER TP-5
PAGE 1 OF 1
PROJECT NAME Dash Paint 2-Lot
PROJECT LOCATION Federal Wa Washin tyn
GROUND ELEVATION 136 ft TEST PIT SIZE
GROUND WATER LEVELS:
AT TIME OF EXCAVATION
AT END OF EXCAVATION —
AFTER EXCAVATION
MATERIAL DESCRIPTION
$
` os
—` ^` Light brown TOPSOIL
_
Tan poorly graded SAND with silt, medium dense, damp (Advance outwash)
-roots to 2.5'
MC = 5.80% -trace gravel
SP-
SM
MC = 8.10%
5
MC = 9.80%
SP
10
MC = 10.70%
Tan poorly graded SAND, dense, moist
-becomes gray, increasing grain size
Test pit terminated at 10.5 feet below existing grade. No groundwater encountered
during excavation. No caving observed.
Bottom of test pit at 10.5 feet.
Appendix B
Laboratory Test Results
ES-5321
Earth Solutions NW, LLC
Earth Solutions NI _C
1805 - 136th PL N.E., Suite 201
Bellevue, WA 98005
Telephone: 425-449-4704
Fax: 425-449-4711
CLIENT Blue Hawaii Inn, LLC cla C.E.S. NW, Inc
PROJECT NUMBER ES-5321
,"RAIN SIZE DISTRIBUTION
PROJECT NAME Dash Point 2-Lot _
PROJECT LOCATION Federal Way,Washington
HE
IN
I
iiii
01
INN
1111
IN
ME
1111
0
IN
!I1
1
i
I
in
111
110
11
0
INS
I
111
Sol
I
IINI
0
IN11
11111
ME
I! Now
H
1111
NONE
1111
IIN
MEN
III
I
III
mumollull
COBBLES
en
Z Specimen Identification
`�' • 1
TP-1 4.00ft.
m
TP-2 4.00ft.
0
Z A
TP-2 6.00ft.
o *
TP-3 3.00ft.
T o
TP-4 6.00ft.
a Specimen Identification
N •
TP-1 4.0ft.
LU
o m
TP-2 4.0ft.
w
TP-2 6.0ft.
Z *,
TP-3 3.0ft.
91 e l TP-4 6.0ft.
SILT OR CLAY
coarse I fine coarse medium I fine
Classification
USDA: Tan Slightly Gravelly Fine Sandy Loam. USCS: SM.
USDA: Tan Slightly Gravelly Sand. USCS: SP.
USDA: Gray Slightly Gravelly Sandy Loam. USCS: SM.
USDA: Tan Slightly Gravelly Sand. USCS: SP-SM.
USDA: Tan Slightly Gravelly Sand. USCS: SP.
D100 D60 D30 D10 ILL PL PI
19 0.239
4.75 0.361 0.222 0.138
9.5 0.198
9.5 0.372 0.21 0.11
4.75 0.383 0.258 0.156
Cc I CU
0.99 1 2.62
1.08 3.38
1.11 2.45
%Silt %Clay
33.5
4.5
38.2
5.4
4.4
Report Distribution
ES-6321
EMAIL ONLY Blue Hawaii Inn, LLC
c/o C.E.S. NW, Inc.
310 — 29t' Street Northeast, Suite 101
Puyallup, Washington 98372
Attention: Ms. Rachel Mattock
Earth Solutions NW, LLC
CEOS'NWInc.
Civil Engineering & Surveying
September 12, 2017
RECEIVE
SEP 12 2017
CITY OF FEDERAL. WAY
GOMMUNITY DEVELOPMENT
City of Federal Way
Department of Community Development
33325 81h Ave South
Federal Way, WA 98003
RE: Federal Way 2 lots Pre -Application Request (CES #17067)
Dear Sir or Madam:
3 l0 29`h St. NE, Suite 101
Puyallup, WA 98372
Phone: (253) 848-4282
Fax: (253) 848-4278
This letter serves as a request for a pre -application meeting regarding potential land use
of parcels 1121039013 and 1121039038 located along SW Dash Point Road, Federal
Way, Washington. Both parcels are currently vacant land and are zoned RS 15, allowing
for 15,000 sf lots. The proposed project is a Boundary Line Adjustment to create a
buildable area on the northern parcel.
The northern portion of parcel 1121039038 contains a stream and an Erosion Hazard
Area. A geotechnical report has been prepared on the parcels. Our included site plan
shows the geologic hazard area measured from the top of the 40% slope. There is a 15-
foot geologic hazard buffer from this line, and a 5-foot structural setback from the buffer.
This allows the potential building envelope to be 20-feet from the top of slope. Our site
plan shows the above -mentioned lines, as well as the adjusted lot line south. The adjusted
lot line decreases the size of the southern parcel to 15,061 sf, which meets the minimum
lot size for the RS 15 zone.
Our site plan was designed using the following setbacks:
+ Minimum Lot Size: 15,000 sf
• Minimum Front Yard Setback: 20-feet
• Minimum Rear Yard Setback: 5-feet
+ Minimum Side Yard Setback: 5-feet
We look forward to meeting with staff and bringing this project to fruition. Please
contact us x�4th t�eting date, time and location upon scheduling.
CES NW, Inc
10/5/2017
Planning
Find Parcel Find Address Print
Results t+
Clear NJ
2 C 1121039038(1)
IJ 1121039038
CFW Intranet
cfwgisweb/Planning Map Set/Default.aspx
11
31005
112103 9116
RS 31015
I O.V
31,025
i121039i1
3110.7
12103,911,
31117
112103 9114
IL
0390B-2
Minor 0
RS15,0
RS15.0
http://cfwgisweb/Planning°/.20Map°/`2OSetIDefault.aspx 1/1
CIT
A�k Federal Way
October 3, 2017
Rachel Mattock
C.E.S. NW, Inc.
310 29"' Street NW, Suite 101
Puyallup, WA 98372
rmattock&(evntivinc. com
33325 8th AvenueF1 L- Fout
Federal Way, WA 98003-6325
(253) 835-7000
www. cityoffederalway. com
Jim Ferrell, Mayor
RE: File #17-104396-00-PC; Preapplication Conference Scheduled
Federal Way 2-Lot 13.LA, Parcel #'s 112103-9013 & 112103-9038, Federal Way
Dear Ms. Mattock:
The Community Development Department is in receipt of your preapplication conference request. The
application has been routed to members of the Development Review Committee and a meeting with the
project applicant has been scheduled as follows:
9:00 a.m. — Thursday, October 12, 2017
Hylebos Conference Room
Federal Way City Hall, 2"d Floor
33325 8"' Avenue South
Federal Way, WA 98003
We look forward to meeting with you. Please coordinate directly with anyone else you would like to
attend the meeting as this will be the only notice sent by the department. If you have any questions
regarding the meeting, please contact me at becky.chapinRwcitvoffederalway.com, or 253-835-2641.
Sincerely,
14 r
Becky Cha i
Associate Planner
Doc I D 70627
CITY OF FEDERAL WAY
COMMUNITY DEVELOPMENT DEPARTMENT
DEVELOPMENT REVIEW COMMITTEE TRANSMITTAL
DATE: October 3, 2017
TO: Cole Elliott, Development Services Manager
Peter Lawrence, Plans Examiner
Rick Perez, City Traffic Engineer
Brian Asbury, Lakehaven Water & Sewer District
Chris Cahan, South King Fire & Rescue
FROM:
Becky Chapin — Associate Planner
FOR DRC MTG. ON. Sorry about the quick turnaround time, this preapp came in a few weeks ago
and I was working with applicant to potentially cancel. Applicant would like
to move forward with the meeting.
October 5, 2017 — Internal meeting at 10:00am, email me if you don't have
comments or can't make it.
October 12, 2017, 9:00am - with applicant
FILE NUMBER(s): 17-104396-00-PC
RELATED FILE NOS.: None
PROJECT NAME: FEDERAL WAY 2-LOT BLA
PROJECTADDRESS: *NO SITE ADDRESS*
ZONING DISTRICT: RS 15.0
PROJECT DESCRIPTION. Proposed boundary line adjustment for single family site.
LAND USE PERMITS.
PROJECT CONTACT.
MATERIALS SUBMTfTED:
Preapplication Conference
Rachel Mattock
CES NW, Inc.
310 29`h St NE, Suite 101
Puyallup, WA 98372
■ Master Land Use Application
• Site Plan
• Project Narrative
• Geotechnical Report
Becky Chapin
From: Becky Chapin
Sent: Friday, September 29, 2017 10:02 AM
To: 'rmattock@cesnwinc.com'
Subject: Federal Way 2 Lots
Hi Rachel,
I wanted to follow-up with you regarding the Not BLA Preapplication Conference you submitted to the City. We briefly discussed the
issues earlier this week. A preapplication is not required for a BLA and based on the limited scope of the project, there won't be many
comments the City can provide.
The main issue is providing access to the property, the property appears to be land locked and direct access to SW Dash Point is not
shown. Frontage improvements are not required for a BLA, and any access easement to the back lot is typically private. The applicant
will have to show how they have access to Dash Point when submitting a BLA application. If you would like to discuss the access
easement or access requirements, you can contact Ann Dower, Senior Engineering Plans Reviewer, directly at 253-835-2732. This
may be a better solution than spending the money on a preapplication conference.
You will need to show the stream and buffer on the BLA drawing. Also, the geotechnical report will need to be peer reviewed by the
City consultant at the applicant's expense. We can start the process by sending the submitted geotech report to our consultant for a
task authorization/cost estimate. If you agree to the cost estimate provided by our consultant we can begin peer review of the report.
From there, the applicant can then submit the BLA application for review.
I can continue the preapplication conference and get something on the schedule for October 12, or cancel the BLA and refund the
money. Or I can cancel the preapplication and the funds can be used for the BLA when it's submitted. Either way, we will need to peer
review the geotechnical report. I will not do anything with the report until I hear from you. Please let me know how you would like to
proceed.
Thanks,
Becky Chapin
Associate Planner
._ � eedelralway
33325 81h Avenue South
Federal Way, WA 98003-6325
Phone:253-835-2641 Fax: 253-835-2609
www.citvoffedera Iway.co m
RECEIVES.
SE P 12 2017 MASTER LAND USE APPLICATION
DEPARTMENT OF COMMUNITY DEVELOPMENT
C11Y OF FEDERAL WAY ` 33325 8'h Avenue South
CITY OFVZ*�4�,L COMMUNITY DEVELOPMENT Federal Way, WA 98003-6325
Federal Way 253-835-260 t Fax 253-835-2609
www.cilvuflcdcraht ay._corn
com
APPLICATION NO(s) 1 i — Date 1 - 162- / 7 _
Project Name
Federal Way 2 lots BLA
Property Address/Location
Parcel Number(s)
The property is accessed off of Dash Point Road.
1121039013 and 1121039038
Project Description Pre-ApRlication meeting request fora potential BoundaLy Line Adjustment for future sin le -
family development.
PI FARE. PRINT
Type of Permit Required
Annexation
Binding Site Plan
Boundary Line Adjustment
Comp Plan/Rezone
Land Surface Modification
Lot Line Elimination
X_ Preapplication Conference
Process I (Director's Approval)
Process fI (Site Plan Review)
Process III (Project Approval)
Process IV (Hearing Examiner's Decision)
Process V (Quasi -Judicial Rezone)
Process VI
SEPA w/Project
SEPA Only
Shoreline: Variance/Conditional Use
Short Subdivision
Subdivision
Variance: Commercial/Residential
Required Information
RS 15 Zoning Designation
SF - Med Dens Comprehensive Plan Designation
Value of Existing Improvements
Value of Proposed Improvements
International Building Code (IBC):
Occupancy Type
Construction Type
Applicant
Name: CES NW, Inc
Address: 310 29th ST NE, Suite 101
City/State: Puyallup, WA
Zip: A253-848-4
8372
Phone: Fax: Email: com
Signature:
Agent (ifdif'er than Applicant)
Name:
Address-
City/State:
City/State:
Zip:
Phone:
Fax:
Email:
Signature:
Owner
Name: Blue Hawaii Investments, LLC
Address: 42-117 Old Kalanianaole Road
City/State: Kailua, HI
Zip: 96734
Phone:
Fax:
Email: les@2h2ohana.com
Signature:
Bulletin #003 —January 1, 2011 Page I of 1 k:\Handouts\Master Land Use Application