17-102938R
RECEIVED COMMUNITY DEVELOPMENT DEPARTMENT
33325 8`h Avenue South
JUN 2 U 2017 Federal Way, WA 98003-6325
CITY of 253-835-2607; Fax 253-835-2609
Federal Way CrrYOFFEDERAL WAY www.cityoffedei-alwU.com
COMMUNITY DEVELOPMENT
SHORELINE SUBSTANTIAL DEVELOPMENT PERMIT
EXEMPTION APPLICATION
File # 17— 1 029 3�� 'ac>
TO BE COMPLETED BY APPLICANT
Project Name: OgQRGH/Gg�, DE G/< .UA15 R PA,)M 1 JV
Project Address: J 1-3 (, 3 W Fo _ PLA(,+- or ,
Applicant: STEP R E m i,
Mailing Address: `0 S 01 2 (77 F 6 11Lci oTo
Phone
Number: 1 06) 6i� — 11 E-mail:
Description of Project:
The Churchill residence is a three story building with decks on all levels overlooking the water.
An unheated storage room is below the lowest deck. The decks and walkway changes were
permitted in 2007 by previous owners. This project is for underpinning the decks' and storage
room's foundations to mitigate further settlement. We suspect that these structures are
supported inadequately on existing gabions.
Meets the criteria for exemption under which section of* WAC 173-27-040:_-2=1) td
*Washington Administrative Code online: anos.leg.wa.gov
r
Applicant's Signature
Date
Bulletin #143 — March 25, 2013
1 of 2
k:\Handouts\Shoreline Exemption
TO BE COMPLETED BY STAFF
1) The proposed development is consistent with Section --;t � of WAC 173-27-040
and is therefore exempt from the Substantial Development Permit Process.
❑ No (explanatory narrative attached)
�
+ +
o�,}► � �Yl CGS 0 f VU caa p i r���`�
2) PropasT require * ff {,v C L
0
Yes Na
❑ C1 � Shoreline Variance
ElQ Shoreline Conditional Use
❑ Review, Approval or Permit by other State or Federal Agency
3) Proposal complies with applicable provisions of the City's Shoreline. Master Program.
C: Yes ❑ No Condition(s) attached: Q,' Yes ❑ No
4) In accordance with FWRC Section 15.05.130, this application is hereby:
Q/ Approved ❑ Denied
Director, Community & Economic Development
Distribu on: " n�� �iC i
/Ap licant (qjv+rA EVE ' U
p/ caner v
File
❑ Outside Agency
Bulletin # 143 —March 25, 2013
2 of 2
�rl2,; t1/7
Date
k:\Handouts\Shoreline Exemption
Ellisport
Engineerinq, Inc.
Scone of Work
Ellisport Engineering, Inc. was asked to investigate minor interior cracking and decks settlement
of the Churchill residence. For background information, we've included multiple geotech
reports, design drawings of the deck, and deck structural calculations.
We believe the deck settlement is due to the posts being founded on gabion rock baskets, which
are likely deforming and settling over time, and not on a proper foundation. Our drawings
propose installing pin piles or push piers under the existing storeroom stemwall and deck posts,
plus a new structural slab for the storeroom. Existing timber framing is adequate.
Besides the background deck and site information, we've provided drawings, general notes, and
structural calculations for permit submittal. We believe this work to be minor in impact and
hope that it can be accomplished through field inspections. We do recommend that the geotech
be on -site for observance of the piles' installation.
The information in this report generally conforms to the 2015 International Building Code.
Questions about this information should be addressed to the undersigned.
Stephen T. Kicinski, PE
Ellisport Engineering, Inc.
4
CITY OF 4A
Federal Way
Approval Conditions
Shoreline Exemption Approval
Federal Way Revised Code (FWRC) 15.05.130 `Shoreline Exemption'
Churchill Deck Underpinning File #17-102938-00-SH
The Planning Division has approved the attached shoreline substantial development permit exemption based
on the exemption provision from WAC 173-27-040(2)(d) `Emergency Construction', relevant code sections
of FWRC Chapter 15.05 Shoreline Management, approved site plan received June 20, 2017, and the
following conditions and recommendation.
Proposal
The applicant proposes to stabilize an existing single family home using pin-piles/underpinning to mitigate
further settlement.
Conditions of Approval
1. A qualified professional engineer shall be present on site to inspect clearing/grading activities
throughout construction in geologically hazardous area.
2. Geotechnical engineer of record to provide inspection report to the city per FWRC 15.10.160.4.c.
3. Soils may not be transported offsite to neighboring property, the public right-of-way, or into the
water. Install silt fence or other erosion control measures as deemed necessary by storm water
inspectors.
4. Geotechnical report to be reviewed by a third party consultant (it appears the prior reports were
not peer reviewed for the construction of several decks). If there are amendments requested by
AMEC Foster Wheeler, applicant shall incorporate them during construction due to the site
erosion (FWRC 15.10.160.4.b).
5. The applicant shall implement all recommendations in AMEC Foster Wheeler's third party
review memo dated August 3, 2017.
6. Shoreline improvements shall be limited to the scope of the submitted permit (installing pin -piles
and remove/replacing concrete slab).
Am
7. Call the Public Works Storm Water division to schedule an, inspection to construction.
Prepared by: Leila Willoughby -Oakes, Associate Planner
17-102938-00-SH
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August 3, 2017
Project No. 5-917-17902-0
Ms. Leila Willoughby -Oakes
City of Federal Way
Community Development Department
33325 8th Avenue South
Federal Way, Washington 98003
Subject: Geotechnical Review of Documents
Churchill Residence
3136 SW 302nd Place
Federal Way, Washington
Dear Ms. Willoughby -Oakes:
amec 4V
foster
wheeler
This letter presents the results of our third -party review of geotechnical engineering reports and
related documents for the proposed improvements to the single family residence. At your request, we
reviewed the following documents:
Geotechnical Engineering Report dated November 9, 2016, prepared by GeoResources, LLC
(GeoResources);
• Three draft plans sheets for pin piles, not stamped or signed, dated April 1, 2017, by Ellisport
Engineering, Inc.; and
Deck Stability Assessment, dated April 23, 2004, by Associated Earth Sciences, Inc.
As outlined within the Third -Party Geotechnical Report Review letter dated October 26, 2016, from the
City of Federal Way Planning Division our review tasks were:
1. Review submitted documents for conformance to Federal Way Revised Code Article IV
Geologically Hazardous Areas Development.
2. Visit the site to observe conditions.
3. Provide written response as to whether or not we concur with GeoResources' findings and
conclusions.
4. Review resubmitted documents as necessary.
Amec Foster Wheeler
Environment & Infrastructure, Inc.
4020 Lake Washington Blvd, Ste 200
Kirkland, Washington 98033
(425) 368-1000 Phone
www.amecfw.com
\\Sea-fs1\WordProc\_Projects\17000s\17902 City of Federal Way\Review Letters\2017_08-03_Chruchill Res review letter_Sx.docx
Ms. Leila Willoughby -Oakes
City of Federal Way 14V
amee
August 3, 2017 foster
Page 2 of 4 wheeler -
SITE AND PROJECT DESCRIPTION
The project site is an existing single family residence located at the top of a coastal bluff. The house
steps down the slope with a daylight basement. Beyond the lowest floor there is a paved patio about
five feet wide and then the slope drops steeply down to the beach. The slope is armored/supported
with gabions and a concrete bulkhead. The site is considered a geologically hazardous area due to
the steep coastal bluff.
The proposed project is to install pin piles or helical piers to support a basement slab and a deck
which has experienced excessive deformation, both lateral movement and vertical settlement.
REVIEW COMMENTS
We agree with the concept of installing pin piles or helical piers to improve support of the structure;
however, more information is needed regarding the site conditions and cause of the damage. It is
important to document the existing conditions and the most likely causes of damage so that the
appropriate solution can be constructed to stabilize the structure and so that future monitoring can
verify stability. The additional information is needed to determine the extent of pile/pier support
needed and to understand the risk of damage in the future.
Provided below are requests for additional information. Our review and comments have been based
on the City of Federal Way critical area regulations and standard engineering geology and
geotechnical engineering practices in the Puget Sound region.
Geotechnical Engineering Report
1. Summarize the current damage to the structure; discuss the portions of the house that have
deformed, the direction and magnitude of deformation, and portion of the slope that has most
likely deformed.
2. Summarize how surface water is managed (or not managed) at the site.
3. Note that the AESI report concluded that the slope was stable and the basement slab and
deck were adequately supported. Also, from our interview with the current owner, we
understand deformation was not present at the time of purchase. Please provide opinions as
to why movement has occurred recently and not previously.
Ms. Leila Willoughby -Oakes
City of Federal Way
August 3, 2017
Page 3 of 4
amen
foster
wheeler
4. Provide a geologic cross-section of the house and bluff. Sheet 3 of the plans might provide a
sufficient base. Include the structure, the gabions, the bulkhead, the soil borings, interpreted
soil layers, interpreted groundwater, and interpreted zone of deforming soil.
5. Assess the condition of the gabions and bulkhead based on visual reconnaissance.
6. Comment on whether the landslide and groundwater seepage (observed during our site visit
on July 31, 2017) on the adjacent property to the north is related to the deformation of the
structure.
7. Analyze the global stability of the slope in the current conditions and after construction of the
piles/piers. Also analyze the seismic stability after construction.
8. Provide seismic design parameters to the structural engineer based on the current codes or
state the probability of exceedance of earthquake motion used for design.
9. Comment on whether the piles/piers will increase the loads on the gabions or the bulkhead
and if they will be stable.
Plan Sheet Review
1. The plan sheets should be stamped and signed by a professional engineer.
2. Include surface water drainage control features (roof drain tightlines, etc.) to reduce the risk of
erosion, settlement, and slope failure.
3. Include structural notes stating the design assumptions, including the design earthquake
loads.
4. The geotechnical engineer should review the latest plan sheets to confirm the geotechnical
recommendations contained within their report have been properly interpreted and
implemented.
Other Comments
1. We recommend GeoResources be on site during construction to monitor installation of the
piles/piers, temporary erosion and sediment control, confirm construction activities do not
adversely affect slope stability, and to check permanent erosion control and surface drainage
controls at the end of construction.
Ms. Leila Willoughby -Oakes
City of Federal Way
amec
August 3, 2017 foster
Page 4 of 4 wheeler
CLOSURE
We appreciate the opportunity to be of service. It should be noted that our scope of work for this third
party review was limited to a review of the documents supplied to us and a visit to the site. Our scope
did not include subsurface exploration or engineering analyses, nor does our review purport to verify
the accuracy of the geotechnical engineering results presented within the documents.
If you have any questions, please contact us at your convenience.
Sincerely,
Amec Foster Wheeler Environment & Infrastructure, Inc.
Todd D. Wentworth, P.E., L.G.
Senior Associate
Ph.253-896-1011
Fx.253-896-2633
James and Sylvia Churchill
3136 SW 302"d PI
Federal Way, WA 98023
(253) 219-3955
sylvia.x.churchill@gmail.com
GeoResources,LLC
5007 Pacific Hwy. E., Ste 16
Fife, Washington 98424
November 9, 2016
Geotechnical Engineering Report
3136 SW 302"d PI
Federal Way, Washington
PN: 0121039083
DoclD: Churchill.SW302ndPI.RG
INTRODUCTION
We are pleased to submit this Geotechnical Engineering Report for new deep
foundation elements for the existing single family residence and deck located at 3136 SW
302"d Place in the Dumas Bay area of Federal Way, Washington (PN: 0121039083). The
general site location is shown on the Site Location Map, Figure 1.
Our understanding of the project is based on our communications with you, our
multiple site visits, including our -October 13, Z016 subsurface explorations, our literature
review and our understanding of the City of Federal Way tlevel6pment-regulations.
1111e understand that the deck and storage room below the deck are experiencing
settlement. To mitigate the settlement, we understand you have proposed to underpin
the existing foundation. The existing foundation elements and required modifications
lw,uId be supported with either helical anchors and/or small diameter pin piles -
SCOPE
The purpose of our services was to evaluate the surface and subsurface
conditions at the site as a basis for developing and providing geotechnical
recommendations and design criteria for the proposed pin piles and helical anchors.
Specifically, our scope of services for the project included the following:
1. Reviewing the available geologic, hydrogeologic and geotechnical data for the
site area;
2. Observing subsurface conditions by observing the exposed soils at the site and
by excavating a series qtLhree han sat the site to depths of
approximately 10 to 15 feet below existing grades;
3. Preparing a written Geotechnical Engineering Report summarizing our site
observations and conclusions, and our geotechnical recommendations and
design criteria for pin piles and helical anchors, along with the supporting data.
Churchill.SW302ndPI.RG
November 9, 2016
Page 2
SITE CONDITIONS
Surface Conditions
The site is located in the Dumas bay area of Federal Way at 3136 SW 302�d
Place (PN: 0121039083). The site is roughly rectangular in shape and according to King
County GIS, measures about 15 to 30 feet wide (northeast to southwest) by about 530 to
560 feet deep (northwest to southeast), and encompasses about 12,367 square feet
(0.28 acres). The site is bounded by existing residential development to the east and
west, SW 302"d Place to the south and by Dumas Bay of Puget Sound to the north.
According to topographic information obtained from King County public GIS data
and generally confirmed in the field, the site generally consists of a relatively flat upland
area and a steeply sloping shoreline bluff. The upland area slopes down to the
northwest from Southwest 302"d Place very gradually, on the order of 2 to 5 percent.
Approximately in line with the eastern extent of the residence, the site begins to slope
down to the northwest more steeply. Initially at about 35 percent, and steepening in the
area immediate behind the bulkhead to 55 to 60 percent. Total topographic relief across
the i eis-on-the-or4er-of-;35•to-60-feet_
The existing residence steps down the slope, and provides grade separation by
utilizing a daylight basement configuration along with gabion basket walls. The deck
extends out to the northwest and the lower portion of the deck is enclosed with a slab -
on -grade floor. The outermost deck supports appear to be founded on the upper -most
portion of the gabion baskets. The gabion baskets extend down the slope about 10 to
12 vertical feet. The toe of the slope is protected by an existing cast -in -place bulkhead.
The existing site configuration and topography is shown in the Site and Exploration Plan,
Figure 2.
Vegetation on the site consists of grass and some scattered mature deciduous
trees on the upland area, and a mixture of grass lawn and invasive ivy in the lower,
steeply sloping portion of the site.
Site Soils
The -USDA Natural Resource Conservation Service (NRCS) Web Soil Survey
maps the site as being underlain by Indianola loamy sand (Type InC) soils. The
Indianola soils are derived from sandy glacial outwash that form on slopes of 5 to 15
percent. They are iisted as having a "moderate" erosion hazard and are classified in
hydrologic soils group "A". An excerpt from the above -referenced map is included as
Figure 3.
Site Geology
The Geologic Map of the Poverty Bay 7.5-minute Quadrangle, Washington, Booth,
D.B., Waldron, H.H., and Troost, K.G., (2003) maps the site as being underlain by
recessional sandy lacustrine deposits (Qvrs). These soils were generally deposited near
the end of the Fraser Stade of the Vashon Glaciation, some 12,000 to 15,000 years ago.
The recessional and deposits consist of poorly sorted, lightly stratified mixtures of sand
and gravel that were deposited by meltwater streams and rivers emanating from the
retreating ice mass. They are typically encountered in a medium dense to dense condition
and are considered normally consolidated.
The map also indicates the site is stratigraphically underlain by older deposits of
pre -Olympia age. These deposits typically consist of glacial till and outwash deposits
that have been over -ridden by the ice mass associated with the more recent Vashon
glaciation. As such, they are typically encountered in a dense to very dense condition
Churchill.SW302ndPl. RG
November 9, 2016
Page 3
and exhibit high strength and low compressibility characteristics where undisturbed. An
excerpt of the above referenced map is included as Figure 4.
Subsurface Explorations
On October 13, 2016, a GeoResources geologist visited the site and excavated
three hand augers, logged the subsurface conditions, and obtained representative soil
samples. The locations of the hand auger borings were selected by GeoResources
personnel in the field based on existing site conditions and site access limitations. The
encountered soils were visually classified in accordance with the Unified Soil
Classification System (USCS) in general accordance with ASTM C: 2488, a copy of
which is attached as Figure A-1. Representative soil samples obtained from the hand
augers were placed in sealed plastic bags and taken to a laboratory for further
examination and testing as deemed necessary. The approximate location of each hand
auger hole is shown on the Site and Exploration Plan, Figure 2.
The hand auger logs, included in Appendix A, describe the vertical sequence of
soils encountered at each location, as well as the approximate groundwater depth, if
encountered.
The hand augers excavated as part of this evaluation indicate the subsurface
conditions at specific locations only, as actual subsurface conditions can vary across the
site. Furth rmore the nature and extent of any such variation would not become eviden
Subsurface Conditions
Our hand auger explorations encountered relatively uniform subsurface conditions
that generally confirmed the mapped stratigraphy. Hand auger explorations in the lower
portion of the site (HA-1 and HA-2) generally encountered a few inches of paver sand
overlying 2 to 3 feet of orange -brown gravelly sand with some silt and cobbles that
appeared to be in a medium dense, moist condition. We interpret these upper soils as fill
material placed in previous stages of the site's development. Below the upper fill soils,
and below the topsoil horizon in hand auger HA-3, our hand augers encountered yellow -
gray grading to gray gravelly sand that appeared to be in a medium dense, moist to wet
condition to the full depth explored. We interpret these gravelly sands as recessional
outwash soils, consistent with the mapped stratigraphy in the site area.
t
Groundwater Conditions
Groundwater seepage was not observed in any of the hand auger holes at the time
of excavation nor was any groundwater seepage observed daylighting on the shoreline
bluff. We anticipate fluctuations in the local groundwater levels will occur in response to
precipitation patterns, off -site construction activities, and site utilization.
CONCLUSIONS AND RECOMMENDATIONS
Based on the results of our data review, site reconnaissance and subsurface
exploration program, it is our opinion that helical anchors and pin piles could be used for
the underpin the existing settling foundation. The deepened foundation under pinning
should provide the necessary long term support for the structure, provided it is properly
designed and installed. Pertinent conclusions and geotechnical recommendations
Churchill. SW302ndPI.RG
November 9, 2016
Page 4
regarding the design and construction of the proposed development are presented
below.
Foundation Support
The existing foundation likely consists of conventional spread footings. The
existing foundation elements experiencing settlement could be underpinned with pin
piles, helical anchors or some combination of both. Our recommendations for helical
anchors and pin piles are presented below. Completing deep auger borings was not in
our current scope for this project and therefore SPT blow counts have not been obtained
for this site. All conclusions for final refusal depths of the deep foundations are
estimates only and could be confirmed with test elements if desired. A minimum
embedment of 8 feet is recommended for either system. Refusal should be achieved in
native soils, not the gabion basket backfill.
Helical Anchors
Helical anchors (such as the proprietary systems offered by AB Chance and
Atlas Systems) typically consist of a square or circular shaft (1.5-inch square is typical)
with and 8 to 12- inch diameter helix located at the leading edge. The helix is rotated and
is advanced into the soil like a screw. similar to soil augers common[y used for drilling.
The anchors can be used either in tension or compression and either as underpinning for
foundations or tiebacks for walls. Depending on the capacity required, one or more
helices may be located along the shaft, typically at about 3-foot intervals. The smallest
helix is the one at the tip of the anchor, with the sizes becoming progressively larger.
Helical anchors are screwed into the ground with rotary -type torque motor until
refusal conditions are met. Refusal is typically defined as achieving a specific torque
'thatcorresponbs'to-a-specinc-coTrprersive-�:,.-Edity.PmL
it is typically attached to the structural member it will support using an off the shelf bracket
and tightened to remove the slack from the system.
The lateral capacity of the piling may be taken as the horizontal vector of the
axial pile capacity. The capacity of the anchor in uplift (tension) is related to the torsion
resistance encountered as the anchor is installed. Torque monitoring of individual
anchors is completed as the anchors are installed using a shear pin that shears once the
design load (torque) is achieved.
We recommend that the anchors be designed having a maximum allowable
compressive axial design load of 25 kips. Design loads between 10 and 30 kips are
typical depending on the configuration of the helices and the soils. Anchors should be
spaced a minimum distance of three times the largest helix diameter measured from the
edges of the helices.
The torque required to achieve the design load is typically provided by the anchor
manufacturer based on their testing data. We estimate the depth required to achieve the
desired torque will likely be greater than the depths achieved by our subsurface
explorations. We recommend at least one compression load test be performed in
accordance with the ASTM Quick load test for piles. It should be noted that glacial soils in
the Seattle area often have large gravel, cobbles and boulders that may impede the
installation of helical piles and the contractor should be prepared to mitigate this condition.
Pin Piling
As proposed, pin piling for the project will likely consist of 2-inch diameter,
Schedule-80 steel pipes that are driven into the underlying soils to refusal. Individual
pipe segments typically range from about 5 to 21 feet long and are successively joined
Church111.SW302ndPI.RG
November 9, 2016
Page 5
with external threaded couplings, internal slip couplings, or butt welds as pile driving
progresses.
Regardless of diameter or installation method, we recommend that each pin pile
be driven to a point of refusal during sustained driving. Refusal for 2-inch pin piling is
based on less than one inch of penetration during one minute of sustained driving using
a g0-pound pneumatic hammer. We anticipate that the pin piles will meet refusal in the
underlying sands but may require installation to depths significantly in excess of the
depth of our subsurface explorations; however, because refusal depths are difficult to
predict and because soil conditions could vary significantly across the site, the contractor
should be prepared for variable pile lengths. Also, it may be necessary to modify pile
layouts if rocks or other obstructions are encountered during pile driving.
When refusal has been achieved, the pin piles can be cut to a predetermined
height or elevation. A structural engineer should be responsible for designing the
reinforced steel and foundation elements, including the connection to the existing
foundation. The minimum pile spacing (center to center) should be 6 times the pile
diameter. For corrosion we recommend either galvanized or schedule 80 piles. The
maximum length for 2 inch
In our opinion, a properly installed 2-inch diameter pin piling driven to refusal (as
defined above) will provide the following allowable axial capacities.
Allowable Value
Design Parameter 2-inch-diameter
Static Compressive Capacity 4,000 pounds
Transient Compressive Capacity 6,000 pounds
LIMITATIONS
We have prepared this limited report for The Churchill's and other members of
the design team for use in evaluating a portion of this project. The data used in
preparing this report may be provided to prospective contractors. Our report, conclusions
and interpretations are based on data from others, our subsurface explorations and limited
site reconnaissance, and should not be construed as a warranty of the subsurface
conditions.
Variations in subsurface conditions are possible between the explorations and may
also occur with time. A contingency for unanticipated conditions should be included in the
budget and schedule. Sufficient monitoring, testing and consultation should be provided
by our firm during construction to confirm that the conditions encountered are consistent
with those indicated by the explorations, to provide recommendations for design changes
should the conditions revealed during the work differ from those anticipated, and to
evaluate whether earthwork and foundation installation activities comply with contract
plans and specifications.
The scope of our services does not include services related to environmental
remediation, construction safety precautions, plan review or construction monitoring as
required by the City of Federal Way. Our recommendations are not intended to direct the
contractor's methods, techniques, sequences or procedures, except as specifically
described in our report for consideration in design. Plan review and construction
monitoring services can be provided on a time and materials basis at your request.
If there are any changes in the loads, grades, locations, configurations or type of
facilities to be constructed, the conclusions and recommendations presented in this report
Churchill.SW302nd PI. RG
November 9, 2016
Page 6
may not be fully applicable. If such changes are made, we should be given the
opportunity to review our recommendations and provide written modifications or
verifications, as appropriate.
♦
Within the limitations of scope, schedule and budget, our services have been
executed In accordance with generally accepted practices in this area at the time this
report was prepared. No other conditions, express or implied, should be understood.
Respectfully submitted,
GeoResources LLC
s
Seth Mattos, GIT
Geotechnical Staff
Keith S. Schembs, LEG
Principal
%L6
STM:KSS:DCB/stm
DocID: Churchill. SW302ndPI.RG
Enclosures: Figure 1 — Site Location Map
Figure 2 — Site and Exploration Plan
Figure 3-- NRCS Soils Neap
Figure 4— USG Geologic Map
Appendix A -- Subsurface Explorations
bHER �l
w
S0o4p (�
slaNAl. y/9 d
Dana C. Biggerstaff, PE
Senior Geotechnical Engineer
Federal Way }
`i
i
Approximate Site Location
(map created from King County Public GIS)
,W++
6
GeoResources, LLC
5007 Pacific Highway East, Suite 16
Fife, Washington 98424
Phone: 253-896-1011
Fax: 253-896-2633
Not to Scale
Site Location Map
Proposed Foundation Improvements
3136 SW 302"d Pi
Federal Way, Washington
PN: 0121039083
Doc ID: Churchill.SW302ndPI.F I November 2016 Figure 1
Approximate Site Location
(map created from King County Public GIS)
GeoResources, LLC
5007 Pacific Highway East, Suite 16
Fife, Washington 98424
Phone: 253-896-1011
Fax: 253-896-2633
Not to Scale
Site & Exploration Plan
Proposed Foundation Improvements
3136 SW 302"d PI
Federal Way, Washington
PN: 0121039083
Doc ID: Churchill.SW302ndPI.F I November 2016 1 Figure 2
Approximate Site Location
Map created from Web Soil Survey (http://websoilsurvey.sc.egov.usda.gov/AppMebSoilSurvey.aspx)
Hydrologic
Soil
Soil Name
Parent Material Slopes Erosion Hazard
Soils Group
Type
A
Cb
InC
Coastal Beaches
Indianola loamy sand
-
Sand outwash 5 to 15 Moderate A
5
Not to Scale
NRCS Soils Map
GeoResources, LLC
Proposed Foundation Improvements
5007 Pacific Highway East, Suite 16
3136 SW 302nd PI
Fife, Washington 98424
Federal Way, Washington
Phone: 253-896-1011
PN: 0121039083
Fax: 253-896-2633
Doc ID: Churchill.SW302ndR.F November 2016 Figure 3
Urn
apag t ,'
T7310 — dls�
114
QI - dV ,A,V 9 ava Q
r
r .� �..
rs w.S -r -----
y� ,,, _ 1
�r die ;
Va k
QIS
Approximate Site Location
An excerpt from the Geologic Map of the Poverty Bay 7.5-minute Quadrangle, Washington, Booth, D.B.,
Waldron, H. H., and Troost, K. G., 2003
-Q firs Recessional sandy lacustrine deposits
QDoa Glacial deposits of pre -Olympia age
j GeoResources, LLC
5007 Pacific Highway East, Suite 16 I
Fife, Washington 98424
Phone: 253-896-1011
Fax: 253-896-2633
Not to Scale
USGS Geologic Map 1
Proposed Foundation Improvements
3136 SW 302A PI
Federal Way, Washington
PN: 0121039083
Doc ID: Churchill.SW302ndPI.F November 2016 Figure 4
Appendix A
Subsurface Explorations
SOIL CLASSIFICATION SYSTEM
GROUP
GROUP NAME
MAJOR
DIVISIONS
l
GRAVEL CLEAN
SYMBOL
GW
WELL -GRADED GRAVEL, FINE TO COARSE
GRAVEL
GRAVEL
GP
POORLY -GRADED GRAVEL
COARSE
GRAINED
More than 50%
SOILS
Of Coarse Fraction GRAVEL
GM
SILTY GRAVEL
Retained on WITH FINES
No. 4 Sieve
GC
CLAYEY GRAVEL
SAND
CLEAN SAND
SW
WELL -GRADED SAND, FINE TO COARSE SAND
More than 50%
Retained on
SP
POORLY -GRADED SAND
No. 200 Sieve
More than 50%
Of Coarse Fraction
SAND
SM
SILTY SAND
Passes
WITH FINES
No. 4 Sieve
SILT AND CLAY
INORGANIC
SC
ML
CLAYEY SAND
SILT
FINE
CL
CLAY
GRAINED
ORGANIC
OL
SOILS
Liquid Limit
Less than 50
ORGANIC SILT, ORGANIC CLAY
SILT AND CLAY INORGANIC MH SILT OF HIGH PLASTICITY, ELASTIC SILT
More than 50%
CH CLAY OF HIGH PLASTICITY, FAT CLAY
Passes
No. 200 Sieve Liquid Limit
50 or more ORGANIC OH ORGANIC CLAY, ORGANIC SILT
HIGHLY ORGANIC SOILS PT I PEAT
NOTES:
i . Field classification is based on visual examination of soil
in general accordance with ASTM D2488-90.
2. Soil classification using laboratory tests is based on
ASTM D2487-90.
3. Description of soil density or consistency are based on
interpretation of blow count data, visual appearance of
soils, and or test data.
GeoResources, LLC
5007 Pacific Highway East, Suite 16
Fife, Washington 98424
Phone: 253-896-1011
Fax: 253-896-2633
SOIL MOISTURE MODIFIERS:
Dry- Absence of moisture, dry to the touch
Moist- Damp, but no visible water
Wet- Visible free water or saturated, usually soil is
obtained from below water table
USCS Classification System
Proposed Foundation Improvements
3136 SW 302nd PI
Federal Way, Washington
PN: 0121039083
Doc ID: Churchill.SW302ndPI.F November 2016 l Figure A-1
TOTAL DEPTH: 14.6
TOP ELEVATION:
LATITUDE:
LONGITUDE:
0
5
7.5
paver
DRILLING METHOD: LOGGED BY: STM
DRILLING COMPANY: HAMMER TYPE:
DRILL RIG: Hand Au er HAMMER WEIGHT:
NOTES: North access stairs, by stora a room door
TEST RESULTS
Plastic Limit 1 Liquid Limit
0 t 2 % Water Content • 3 c a�
DRILLING a o o
SOIL DESCRIPTION NOTES @ %Fines (<0.075mm) o m v
with some silt occasional cobble and roots
(loose to medium dense, moist)(fill?)
allow -gray sand with some silt (loose to
medium dense, moist)(weathered outwash
sand?)
ray sandy gravel (medium
moist)(outwash)
gray
10
2.5
15
CompletedOct 13, 2016
NOTES
1. Refer to log key for definition of symbols, abbreviations and codes
2. USCS designation is based on visual manual classification
and selected lab testing
3. Groundwater level, if indicated, is for the date shown and may vary
4. N.E. = Not Encountered
5. ATD = At the Time of Drilling
Penetration - ♦ (blows per foot)
Proposed Foundation Improvements
302rid PI
Federal Wav, WA
LOG OF BORING HA-1
JOB: Churchlll.SW302ndPl snout 9 of r
GeaResources. LLC I FCC.
TOTAL DEPTH: 4.5
TOP ELEVATION:
LATITUDE:
LONGITUDE:
DRILLING METHOD:
_ DRILLING COMPANY:
_ DRILL RIG:
NOTES:
SOIL DESCRIPTION
o �
0 ray paver
5
(loose, moist)(fill?)
moist)(outwash)
5- f CompletedOctober 13. 2016
7.5
10
2.5
15
DRILLING
NOTES
NOTES
1. Refer to log key for definition of symbols, abbreviations and codes
2. USCS designation is based on visual manual classification
and selected lab testing
3. Groundwater level, if indicated, is for the date shown and may vary
4. N.E. = Not Encountered
5. ATD = At the Time of Drilling
Proposed Foundation Improvements
302nd PI
Federal Way, WA
LOG OF BORING HA-2
JOB: Churchill.SW302ndPl Sheet , or ,
GeoResources LLC FIG.
TOTAL DEPTH: _
TOP ELEVATION:
LATITUDE:
LONGITUDE:
c
0
aai >
o �
u�
0
2.5
5
7.5
10
2.5
15
NOTES
10.5
SOIL DESCRIPTION
DRILLING METHOD:
DRILLING COMPANY:
DRILL RIG: _
NOTES: _
range- rown gravelly sand with some
(loose to medium dense, moist) (fill?)
medium dense, moist) (weathered outwash)
(outwash)
CompletedOctober 13, 2016
DRILLING
NOTES
1. Refer to log key for definition of symbols, abbreviations and codes
2. USCS designation is based on visual manual classification
and selected lab testing
3. Groundwater level, if indicated, is for the date shown and may vary
4. N.E. = Not Encountered
5. ATD = At the Time of Drilling
_ LOGGED BY: STM
HAMMER TYPE:
HAMMER WEIGHT:
Side and near to of slope
TEST RESULTS
Plastic Limit Liquid Limit
a -6 % Water Content ■ oco
o
E E % Fines (<0.075mm) O m 0
U) N
Penetration - ♦ (blows per foot)
Proposed Foundation Improvements
302nd PI
Federal Way, WA
LOG OF BORING HA-3
JOB: Churchill.SW302ndPl Shaer 1 ar r
r`nnQacnl trr_c_ I_LC FIG.
Ellisport
m
endix —
20501 81" Ave. S_iV
Vdslloni WA 08070
(206) 463-531 1 (phone;
1206) 463-2578 (fah)
anail(tt.ellislx).rtetigiiicerI r��?.e.��i:
nal Deck Dest
Ellisport
Engineering, Inc.
Scone of Work
Ellisport Engineering, Inc. was asked to investigate minor interior cracking and decks settlement
of the Churchill residence. For background information, we've included multiple geotech
reports, design drawings of the deck, and deck structural calculations.
We believe the deck settlement is due to the posts being founded on gabion rock baskets, which
are likely deforming and settling over time, and not on a proper foundation. Our drawings
propose installing pin piles or push piers under the existing storeroom stemwall and deck posts,
plus a new structural slab for the storeroom. Existing timber framing is adequate.
Besides the background deck and site information, we've provided drawings, general notes, and
structural calculations for permit submittal. We believe this work to be minor in impact and
hope that it can be accomplished through field inspections. We do recommend that the geotech
be on -site for observance of the piles' installation.
The information in this report generally conforms to the 2015 International Building Code.
Questions about this information should be addressed to the undersigned.
Stephen T. Kicinski, PE
Ellisport Engineering, Inc.
2
PRE -BUILT CONDITIONS - BONIFACE RESIDENCE
(PHOTOGRAPH WAS TAKEN BEFORE MARCH 2001)
BONIFACE RESIDENCE
DECK RECONFIGURATION
3136 SW 302nd PLACE
FEDERAL WAY, WA. 98003
DATE 5/11/04
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CITY OF
t Federal Way
July 10, 2017
Ms. Sylvia Churchill
3136 SW 302nd Place
Federal Way, WA 98023
s vi , u rc� i .cam
CITY HALL
33325 8th Avenue South
Federal Way, WA 98003-6325
(253) 835-7000
www. cityofiederalway. com
Jim Ferrell, Mayor
FILE
Re: File #17-103247-00-AD; GEOTECHNICAL PEER REVIEW ESTIMATE
Churchill Residence Settlement Repair/Pin Piles — 3136 SW 302nd Place, Federal Way
Dear Ms. Churchill:
As a condition of the single-family building permit approved as an emergency shoreline exemption, the
applicant must pay for the services of a qualified professional engineer retained by the city to review the soils
report and other relevant information (Federal Way Revised Code [FWRC] 15.10.160[4] [b]). Enclosed please
find the consultant task authorization form and invoice, which includes a scope of work, to review the
Geotechnical Engineering Report (3136 SW 302nd Place, Federal Way) prepared by GeoResources, LLC
(November 9, 2016). The report is limited in scope and does not explain the settlement event and does not
contain a slope stability analysis.
When authorized by you, the city will set up an account to be funded by you and drawn down as the third -
party peer review work is performed by AMEC Foster Wheeler (AMEC). If any funds are not used, they will
be returned to you. Please submit a check in the amount of $3,000.00, made payable to the City of Federal
Way; and sign and return the enclosed in order (with the fee) for the review to begin. Additional report
reviews and subsequent revisions may require supplemental fees and authorization. Following the receipt of
the form and fees, the project planner will authorize AMEC to begin their review.
City technical review comments are subject to change if the city's consultant requires building plan or
geotechnical report revisions. If you have any questions regarding this letter, or the required third -party
geotechnical review, please contact me at 253-835-2644, or lg d n.xvilloughb_�-makes a`tlroffederalway.com.
Sincerely,
t C ' f.7
Leila Willoughby -Oakes
Associate Planner
enc: Task Authorization
Invoice
Mic 17-103247-00-AD Doc. I.D. 76158
CITY OF
�. Federal Way
July 7, 2017
Mr. Todd D. Wentworth, PE, LG
Amec Foster Wheeler Environment & Infrastructure
11810 North Creek Parkway North
Bothell, WA 98011
todd.wentworth ameefw.com
C p3taq -�- -
Re: File #17-x%mr==00-AD; THIRD PARTY GEOTECHNICAL REPORT REVIEW
Churchill Residence Repair/Pin Piles, 3136 SW 302"d Place, Federal Way
Dear Mr. Wentworth:
CITY HALL
33325 8th Avenue South
Federal Way, WA 98003-6325
(253) 835-7000
www. cltyoffederalway.. com
Jim Ferrell, Mayor
Please find the enclosed task authorization form for the abovementioned parcel and related building
permit and shoreline exemption applications 17-102938 -SU and 17-102564-00-SF. The Community
Development Department requests the application undergo a third -party geotechnical report review
pursuant to the agreed terms of the on -call contract to proceed with application processing. Please review
the scope of work contained in the task authorization form, enter the task cost on page 2 of the document,
and return it to the city by email and the signed original by mail. Following the deposit of funds by the
applicant/agent, staff will provide authorization to proceed with the scope of work.
For the purposes of expediting review timelines the city requests the proposed tasks are completed by July
10, 2017. The Planning Division has deemed the repair emergency construction pursuant to Washington
Administrative Code (WAC) 173-27-040(2)(d).
Please contact the me at 253-835-2644, or lei la.wiIlough b -oakes ci offederalwa .coin if you have
any questions regarding this task or the proposed scope.
Sincerely,
Leila Willoughby -Oakes
Associate Planner
enc: Task Authorization
Background Documents
od
Ann Dower, Senior Engineering Plans Examiner
Peter Lawrence, Plans Examiner
Churchill Residence/Foundation Repair Geotechnical Peer Review Letter
CITY OF
Federal Way
GEOTECIINICAL CONSULTANT PEER REVIEW
Date: July 5, 2017
Consultan : . Todd Wentworth
AMEC Foster Wheeler
Project: Churchill Residence/Foundation Repair
3136 SW 302"d Place
Parcel # 012103-9083
File No.: 17-1031247-00-AD
Related Files: 17-102938-00-SH; 17-102564-00-SF
Zoning: RS 7.2
Applicant: James & Sylvia Churchill
3136 SW 302°d Place
Federal Way, WA 98023
5y€via.x.churchill[gmail com
Ellisport Engineering, Inc. (Consultant)
20501 81". Ave. SW
Vashon, WA 98070
206-463-5311
City Staff. Leila Willoughby -Oakes, Associate Planner
Community Development Department
33325 8th Avenue South
Federal Way, WA 98003
253-835-2644 1 Lei la.Wiliou hb -Oakes ci offederalwa .com
Description: Proposal
The applicant proposes to address building settlement issues and underpin the
existing foundation for a single family home located in the 50 ft. shoreline setback.
The proposal includes helical anchors and/or small diameter pin piles.
The city requests AMEC evaluate the existing 2"w and P door deck loads, as the
current proposal is within 25 ft. of an erosion hazard area. The subject property is
increasingly impacted by wave run-up resulting in shoreline erosion.
17-103247-00-AD
Doc. I.D.
Property History —Code Violations
The city issued a code violation on the subject property (city file no. 04-103452-00-
VO) for a remodel/addition of a 2°d floor 125 sq. ft. deck and like size deck on the
third level. The enclosed voluntary correction agreement and deck stability
assessment outline improvements performed without permits in 2003.
■ Review submitted study and background materials for compliance with
Scope of Work: Federal Way Revised Code (FWRC) Article IV. Geologically Hazardous
Areas Development
• Perform site visit to confirm conditions;
• Prepare a letter of findings and conclusions as to whether or not AMEC
Foster Wheeler concurs with GeoResources, LLC report;
• Review of resubmitted documents as necessary:
Documents Provided • Geotechnical Engineering Report, 3136 SW 302" d Pl. prepared by
for Review: GeoResources, LLC (dated November 9, 2016)
• Pin pile/Push Piers plan -set prepared by Ellingsport Engineering, Inc.
(dated June 19, 2017)
• Site Photos
Historical • Deck Stability Assessment, 3136 SW 302°d Place prepared by Associated
Documents: Earth Sciences, Inc. (dated April 23, 2004)1
• Voluntary Correction Agreement Letter (city file no.04-103452-00-VO)
Task Cost: Provide task cost estimate by July 10, 2017
Not to exceed $ 3 a a without a prior written amendment to this Task
Authorization.
The total task amount completed by city staff after the third party consultant returns
this form. All spaces are to be completed including the total work estimate, on the
grounds that the estimate has been approved by the Project Planner.
t lG 2--9(7-
Way (Project Planner, Leila Willoughby -Oakes) Oale
I-S79 -7 171
City Consultant (Todd Wentworth, AMEC Foster Wheeler) Date
Ct.M.lcl_lkI�4 4.
Project ProponYnt/Agent (Sylvia C. Churchill)
1 Requested by the city for site improvements made without a building permit.
-I -1$ - F)
Date
17-103247-00-AD Doc 1 D.
Leila Willoughby -Oakes
From: Leila Willoughby -Oakes
Sent: Wednesday, July 05, 2017 5:09 PM
To: 'Wentworth, Todd D'
Cc: Robert Hansen
Subject: Churchill Peer Review (Parcel: 012103 9083
Attachments: 20170705170710.pdf, 20170705170647.pdf, 20170705170619.pdf
Hi Todd,
We are seeking a quick turn -around for a peer review for an emergency underpinning of a deck on the Puget Sound.
FWRC 15.10.160 applies and it will undergo construction per WAC 173-27-040(2) ( e). I am pulling the archived files as
the property had unpermitted decks (2"d and 3rd floor) added in the early 2000's.
Any technical comments you have on testing or BMPs would need to implemented by GeoResources during
construction. If there are no issues, a signed and stamped memo would be requested for the file. The report and prior
reports are attached.
Would you be able to give me a quote by tomorrow or Friday?
Let me know if you have any questions/your schedule.
Thanks again,
Leila
L. Willoughby -Oakes
Associate Planner
Fe" ielrai Way
33325 8th Avenue South
Federal Way, WA 98003-6325
Phone:253/835-2644 Fax: 253/835-2609
w ww.c ityoff ede ra I way.com
CITY OF FEDERAL WAY
COMMUNITY DEVELOPMENT
rADnnD-r
FLOOR PLAN
1/4" = V-0"
• - MIN 2" 0 PIN PILE/PUSH PIER
DRIVEN TO REFUSAL
GEOTECH OBSERVATION REQUIRED
rat 4i cC
SECTION/3
General Notes
No. I Revision/Issue I Date
Firm Name and Address
ELLISPORT ENGINEERING, INC.
20501 81 st Ave SW
Vashon, WA 98070
206.463.5311 - phone
206.463.2578 - fax
Project Name and Address
CHURCHILL RESIDENCE
3136 SW 302nd Place
Federal Way, WA 98003
CCH
ject Sheet
URCHILL RES.
Date
19 JUN EEngin�eer
DrafterDSD
-- - - --701
-- - - -60'
- - - - --501
- - 40'
-- - - - - --301
- - - - - --201
- —10'
0'
SECTION
1/4" = V-0"
General Notes
No. I Revision/Issue I Date
Firm Name and Address
ELLISPORT ENGINEERING, INC.
20501 81 st Ave SW
Vashon, WA 98070
206.463.5311 - phone
206.463.2578 - fax
Project Name and Address
CHURCHILL RESIDENCE
13136 SW 302nd Place
Federal Way, WA 98003
r
ject Sheet
HURCHILL RES.
pDrafter
UN 2017
Engineer
STK