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HomeMy WebLinkAboutMiscKinkade Crossing
Preliminary Technical Information Report
August 26, 2015
Prepared for
Taylor Development
15 Lake Bellevue Drive, Suite 102
Bellevue, WA 98005
(425) 869-1300
Submitted by
ESM Consulting Engineers, LLC
33400 81h Avenue S, Suite 205
Federal Way, WA 98003
253.838.6113 tel
253.838.7104 fax
www.esmcivil.com
PRELIMINARY TECHNICAL INFORMATION REPORT
FOR
August 26, 2015
Approved By:
City of Renton
KINKADE CROSSING
Prepared for:
Taylor Development
15 Lake Bellevue Drive, Suite 102
Bellevue, WA 98005
Prepared by:
ESM Consulting Engineers, LLC
33400 81h Avenue S, Suite 205
Federal Way, WA 98003
Job No. 994-001-015
Date
TABLE OF CONTENTS
1. PROJECT OVERVIEW ...................................... . 1-1
2. CONDITIONS AND REQUIREMENTS SUMMARY.................................................. 2-1
3. OFF-SITE ANALYSIS................................................................................ . . .. ..... 3-1
4. FLOW CONTROL & WATER QUALITY FACILITY ANALYSIS AND DESIGN........ 4-1
5. CONVEYANCE SYSTEM ANALYSIS AND DESIGN. ················· 5-1
6. SPECIAL REPORTS AND STUDIES ....................................................................... 6-1
7. OTHER PERMITS............... ....................... 7-1
8. CSWPPP ANALYSIS AND DESIGN................................................ ....................... 8-1
9. BOND QUANTITIES, FACILITY SUMMARIES, AND DECLARATION OF
COVENANT ..... ... ... ... .. .. ... ... ... ... ... ... ... ... .. . ... .. ... ... ... ... ... . .. . .. ... ... . . ... .. . ... . ...... ... ... ... .. ... .. ... 9-1
10. OPERATIONS AND MAINTENANCE MANUAL 10-1
LIST OF FIGURES
1.1 Vicinity Map
1.2 Existing Site Conditions
1.3 Proposed Site Conditions
1.4 Soils Map
3.1 KCGIS Parcel Reports/Environmental Hazards
3.2 Drainage Complaint Map
3.3 Site Topography
3.4 Offsite Analysis Downstream Flowpath
3.5 Offsite Analysis Drainage System Table
4.1 Pond Tributary Area
1. PROJECT OVERVIEW
The proposed Kinkade Crossing Plat is a 17-lot plat located south of the intersection of
116th Ave SE and SE Petrovitsky Rd in the City of Renton, WA. The plat incorporates
one parcel numbered 322305-9303, which is zoned R-8. See Figure 1.1 for the Vicinity
Map.
The existing site consists of 1 single-family dwelling with associated driveway and
several detached sheds near the dwelling. The existing site is relatively flat (mean slope
of 5.5%, less than 10% max slopes on site) with a slope from the southwest to the
northeast corners of the project site. The pervious portions of the parcel are generally
pasture. See Figure 1.2 for the Existing Site Conditions.
The proposed 3.63 acre project site consists of 17 residential lots and 1 open space
tract. All 17 residential lots will have new single-family dwelling units. Those lots will be
5,000 square feet minimum and will be served by a new street from 1771h PL to 1161h
Ave SE and two hammerheads, with one shared access easement off of the south
hammerhead to provide access to lots 4-6. See Figure 1.3 for the Proposed Site
Conditions.
The stormwater detention and water quality treatment will be provided with a combined
detention/water quality pond in the storm drainage tract located in the northeast corner
of the site. The combined detention/water quality pond will discharge east to a proposed
stormwater conveyance system in 1161h Ave SE in the project's east frontage and
ultimately flow east along SE Petrovitsky Rd and enter Big Soos Creek. See Section 3
for the Level 1 Downstream Analysis.
According to the Geotechnical Engineering Report (GER) by The Riley Group, Inc.
(RGI), on July 08, 2015 and attached in Section 6, the soils onsite include loose to very
dense silty sand with gravel. See Figure 1.4 for the Soils Map.
Based on the City of Renton's Flow Control Application Map, the project site is in the
Flow Control Duration Standard (Forested Conditions, Level 2) area. The project will be
subject to Full Drainage Review per the City of Renton 2009 Surface Water Design
Manual Amendments and the 2009 King County Surface Water Design Manual (2009
KCSWDM). The City of Renton 2009 Surface Water Design Manual Amendment and
the 2009 KCSWDM will collectively be referred to as the "2009 Surface Water Design
Manual".
2
Figure 1.1
Vicinity Map
3
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Vicinity Map
Project Name: Kinkade Crossing
Project Address: 17709 116th Ave SE, Renton, WA 98058
lat/Long: 47.444184, -122.187074
S-T-R: 32-23N-5E
Data Source: BING Maps, City of Renton 0 750 1,500
1 inch = 1,500 feet
Figure 1.2
Existing Site Conditions
4
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Figure 1.3
Proposed Site Conditions
r 1 ·1. ----~. l;:q; I I-!,
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Figure 1.4
Soils Map
6
8
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561CB0
56108C
A
Soil Mao-King County Area. Washington
lK1nkade Crossing)
561170 561260 5613SC
561170 5612W '.:G13SO
M,;pSG)le: 1:3,82C fpnr1tcd ur1 A l;:mdsw~ (11" x 8S') sheet.
,o 100 200
---===------======Feec ~ = ~ ~
561~4C
~,,1440
Mete·-s
3oc,
Map prnJechon· W<0h Mercator Comer coordinates: WC,584 Euqe te:, lJTlv1 Zuric :01\ \VGS84
561530
$615JO
U'.,I),\ Natural Resources Web Soll Survey
National Cooperative Soil Survey ..-Conservation Service
' ;
s
~
S61G?O 561710 5611800 561189:J
'17"26'..s"N
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47°26'3l"N
561620 561710 561800 561890
' :;
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8/20/2015
Paqe 1 of 3
~
Soil Map-King County Area, Washington
(Kinkade Crossing)
MAP LEGEND
Area of Interest (AOI)
Area of Interest (AOI)
Soils
D Sorl Map Unit Polygons -Soil Map Unit Lines
II Soil Map Unit Points
Special Point Features
~
181
ill'i
0
X
0
A ..
* 0
0
V
+ :•:
.....
~
3'
I#
Natural Resources
Conservation Service
Blowout
Borrow Pit
Clay Spot
Closed Depression
Gravel Pit
Gravelly Spot
Landfill
Lava Flow
Marsh or swamp
Mine or Quarry
Miscellaneous Water
Perennial Water
Rock. Outcrop
Saline Spot
Sandy Spot
Severely Eroded Spot
Sinkhole
Slide or Slip
SodicSpot
a Spoil Area
0 Stony Spot
ffi Very Stony Spot
\{ Wet Spot
6 Other .. Special Line Features
Water Features
Streams and Canals
Transportation
+-H Rails -Interstate Highways
US Routes
Major Roads
Local Roads
Background • Aerial Photography
Web Soil Survey
National Cooperative Soil Survey
MAP INFORMATION
The soil surveys that comprise your AOI were mapped at 1 :24,000.
Warning: Soil Map may not be valid at this scale.
Enlargement of maps beyond the scale of mapping can cause
misunderstanding of the detail of mapping and accuracy of soil line
placement. The maps do not show the small areas of contrasting
soils that could have been shown at a more detailed scale.
Please rely on the bar scale on each map sheet for map
measurements.
Source of Map· Natural Resources Conservation Service
Web Soil Survey URL: http://websoilsurvey.nrcs.usda.gov
Coordinate System: Web Mercator (EPSG:3857)
Maps from the Web Soil Survey are based on the Web Mercator
projection, which preserves direction and shape but distorts
distance and area. A projection that preserves area, such as the
Albers equal-area conic projection, should be used if more accurate
calculations of distance or area are required.
This product is generated from the USDA~NRCS certified data as of
the version date(s) listed below .
Soil Survey Area: King County Area, Washington
Survey Area Data: Version 10, Sep 30, 2014
Soil map units are labeled (as space allows) for map scales 1 :50,000
or larger.
Date(s) aerial images were photographed: Aug 31, 2013-Jul 15,
2014
The orthophoto or other base map on which the soil lines were
compiled and digitized probably differs from the background
imagery displayed on these maps. As a result, some minor shifting
of map unit boundaries may be evident.
8120/2015
Paqe 2 of 3
Soil Map-King County Area, Washington Kinkade Crossing
Map Unit Legend
l Alderwood gravelly sandy loam, : 41.1 58.2%
i O to 8 percent slopes '
AgB
AgC
Totals for Area of Interest
Natural Resources
Conservation Service
I
Alderwood gravelly sandy lo~;,
B to 15 percent slopes
Web Soil Survey
National Cooperative Soil Survey
29.6
70.7
41.8%
100.0%
8120/2015
Page 3 of3
2. CONDITIONS AND REQUIREMENTS SUMMARY
Review of the 8 Core Requirements and 6 Special Requirements
This section describes how the project will meet the 2009 Surface Water Design
Manual's Core and Special Requirements.
Core Requirement No. 1 Discharge at the Natural Location
In the existing conditions, the site drains to the northeast, however the flows converge
about 200 feet downstream, at the intersection of SE Petrovitsky and 1161h Ave SE. In
the proposed condition, the combined detention/water quality pond will discharge east
on 1161h Ave SE, which is the natural discharge location for the project site.
Core Requirement No. 2 Off-site Analysis
A Level 1 Downstream Analysis was performed by ESM on June 22, 2015. See Section
3 for the offsite analysis.
Core Requirement No. 3 Flow Control
Based on the City of Renton's Flow Control Application Map, the project site is in the
Flow Control Duration Standard (Forested Conditions, Level 2) area. See Section 4 for
Flow Control Analysis and Calculations.
Core Requirement No. 4 Conveyance System
The stormwater drainage conveyance system will be sized as part of the final TIR to
convey the 25 year design storm event and to contain the 100 year design storm event.
Core Requirement No. 5 Erosion and Sediment Control
The proposed project will include clearing and grading for the 17 new single-family units,
open space tract, associated roadways, and pond area. Erosion and sediment controls
will be provided to prevent, to the maximum extent possible, the transport of sediment
from the project site to downstream drainage facilities, water resources, and adjacent
properties. The Temporary Erosion and Sedimentation Control (TESC) Plans will be
shown on the final construction plans and described in the final TIR.
Core Requirement No. 6 Maintenance and Operations
The Operations and Maintenance Manual will be provided as part of the final TIR.
Core Requirement No. 7 Financial Guarantees and Liability
All drainage facilities constructed or modified for projects will comply with the financial
guarantee requirements as provided in the City of Renton Bond Quantities Worksheet.
The Bond Quantities Worksheet, Facility Summaries, and Declaration of Covenant will
be provided as part of the final TIR.
Core Requirement No. 8 Water Quality
According to King County iMap, the project site requires Basic Water Quality. The site
does not meet the requirements for enhanced treatment in the 2009 Surface Water
Design manual. Treatment for the pollution generating surfaces will be provided by a
combined detention/water quality pond. See Section 4 for more information.
Special Requirement No. 1 Other Adopted Area-Specific Requirements
7
There are no master drainage plans, basin plans, salmon conservation plans,
stormwater compliance plans, flood hazard reduction plan updates, or shared facility
drainage plans for this project. Special Requirement No. 1 does not apply.
Special Requirement No. 2 Flood Hazard Area Delineation
There is no 100-year flood plain associated with a large body of water (i.e. lake or
stream) on the site or adjacent to the site. Special Requirement No. 2 does not apply.
Special Requirement No. 3 Flood Protection Facilities
The project lies outside any pre-defined flood plain. Special Requirement No. 3 does not
apply.
Special Requirement No. 4 Source Control
The project is a residential subdivision and is not subject to this requirement. Special
Requirement No. 4 does not apply.
Special Requirement No. 5 Oil Control
The project does not have a "high-use site characteristic" and is not a redevelopment of
a high-use site. Special Requirement No. 5 does not apply.
Special Requirement No. 6 Aquifer Protection Area
According to the "Groundwater Protection Areas in the City of Renton" map, the project
site is not in an Aquifer Protection Area. Special Requirement No. 6 does not apply.
3. OFF-SITE ANALYSIS
Task 1: Study Area Definition and Maps
Figure 1.2 shows the existing site conditions. Figure 3.4 shows the extent of offsite
analysis and the downstream flow path from the site.
Task 2: Resource Review
• Flow Control Map
According to the City of Renton Flow Control Application Map, the site is a Flow
Control Duration Standard (Forested Conditions) area.
• Soil Survey Map
According to the City of Renton Soil Survey prepared by City of Renton Public
Works Department on 01/09/2014, the geologic map of the area indicates that
the soil type on the project site is AgB: ALDERWOOD GRAVELLY SANDY
LOAM, 0 TO 6 PERCENT SLOPES. The GER indicates that the soils onsite
include loose to very dense silty sand with gravel. Further details and
descriptions can be found in the GER attached in Section 6.
King County iMap
According to the King County GIS Viewer (iMap ), the project is NOT in any of the
following areas:
o Streams & 100 year floodplains
o Erosion Hazard Areas
o Seismic Hazard Areas
o Landslide Hazard Areas
o Coal Mine Hazard Areas
o Wetlands
City of Renton 2009 Surface Water Manual Amendments
According to Reference 11-B in the City of Renton 2009 Surface Water Design
Manual Amendments, the project is NOT in any of the following areas:
o Aquifer Protection Areas
o Groundwater Protection Areas
Road Drainage Problems
None noted
Wetlands Inventory
There are no recorded wetlands on or near the site according to iMap and the
1990 King County Wetlands Inventory Notebooks.
• Migrating River Study
None noted
• Downstream Drainage Complaints
9
According to the information available on iMap, there have been no downstream
drainage complaints in the study area within the last 10 years.
to
Figure 3.1
KCGIS Parcel Report/Environmental Hazards
II
8/2112015 King County Districts and Development Conditions for parcel number 3223059303
tQ King County
King County Districts and Development Conditions for parcel 3223059303
Parcel number 3223059303 Drainage
Address Not Basin
Available Watershed
Jurisdiction Renton
_Zipcode 98058 ~I!',_
-----
l<roll_Map p,age 604 PLSS
Thomas Guide 656 and686 Latitude
page_ _Longitude
Electoral Districts
Voti_ng district _____________ ~N_!1_!:«J539
King County Council district District 5, Dave
Upthegrove
(206) 477-1005
Congressional district
Legislative district
School district
9
11
Renton #403
Soos Creek
Duwamish -Green
River
Duwarnish-GreenJ~\ _
NE -32 -23 -5
47.44465
-122.18632
-~--·····--··· --··
Fire district
Water district
Sewer district
Water & Sewer district
Parks & Recreation
district
Seattle school board district does not apply (not in
Seattle)
Hospital district
Rural library district
District Court electoral district Southeast
f<irig Countx p_lanning_~n<:l_c:ritic_al areas_<:lesigna_tions
King County zoning NA, check with
jurisdiction
None
um
Urban
does not apply
Soos Creek
_ None mapped
None mapped
Potential annexation area
Rural town?
Water servic" plannin8 area
Roads MPS zone
Transportation Concurrency
Management
does not apply
does not apply
does not apply
Soos Creek Water & Sewer
District
does not apply
Public Hospital District No. 1
Rural King County Library
System
does not 11 pp_ly
No
does not_ a_11ply
341
does not apply
No
No
None ma_11pe_d_
Development conditions
Comprehensive Plan
Urban Growth Area
Community Service Area
Community Planning Area
Coal mine hazards?
Erosion hazards?
Landslide hazards?
Seismic hazards?
_ None mapped _
Forest Production district?
Agricultural Production district?
Critical aquifer recharge area?
_ 1__D_D-year flood 11lain~---
Wetlands at this parcel?
__ None mapped __
None mapped __ _
Within the Tacoma Smelter Plume?
This report was generated on 8/21/2015 8:25:01 AM
Contact us at giscenter@kingcounty.gov.
© 2015 King County
http11www5.kirgcounty.gov/KCG1SReports/dd_report_print.aspx?PIN=3223059303
None mapped
20.1 ppm to 40.0 ppm
Estimated Ar.;enic Concentration in
1/1
Task 3: Field Inspection (Level 1 Inspection)
A Level 1 Downstream Analysis was completed by ESM Consulting Engineers in the
afternoon on 22 JUN 2015, when it was partly cloudy and 76°F. During the inspection it
was found that the project site appears to be located at a high point with no estimated
offsite areas draining to the property. Typical culverts were 12" CMP along the east
frontage and constricted from vegetation and litter. The edge of the asphalt pavement of
1161h Ave SE has eroded into the roadside ditch in some places along the east frontage
of the project site.
Task 4: Drainage Description and Problem Descriptions
According to iMap, the project site is in the Soos Creek (King County WRIA number: 9)
basin. Big Soos Creek is located to the north and east of the project site.
The project site's high point is the south-west corner which causes the existing site to
flow to the north and east boundaries. All flows on the east boundary flow into a roadside
ditch and enter the storm drainage system on 1161h Ave SE. All flows on the north
boundary enter the storm drainage system on SE 176th St. Some flows at the north-east
corner of the project site sheet flow onto the parcel adjacent to the project at the corner
of 1161h Ave SE and SE 1761h St. All of these flows converge in the storm drainage
system on SE 1761h St and flow along SE Petrovitsky Rd in a piped catch basin system
for about 1300 feet until they are discharged into Big Soos Creek.
Task 5: Mitigation of Existing or Potential Problems
All runoff from the site will be collected in a piped storm system and directed to the
proposed combined detention/water quality pond. From there, runoff will be discharged
at the Flow Control Duration Standard (Forested Conditions) into the existing storm
drainage system in 1161h Ave SE.
12
Figure 3.2
Drainage Complaint Map
13
King County iMap
:;:
Sortri Rnul!'; Kln',l C<1~nl'j
Pa1teli
Parcel,
Ero$1onlll!IUrd(!Sl90$A.0)'
Se1sm1~ hw:aro \1990 SAO)
landshdehaz:ard ('.990$AO)
Coal mine hua'd (1990 SAO)
c1au1
eiass 2 p111,rl!n~,a1
ti~u 2 salftlo~.d
clanJ
We~;md(1S90 SAO)
S!!nsrh'I! ,1rl!; nollCI! 011 ~Ile
res111en11al
Dra1niilil~ comdain~
Figure 3.3
Site Topography
15
;;
SUn:h Res~II'!, King Counr.,,
Parc!"!I
Parte!s
Figure 3.4
Offsite Analysis Downstream Flowpath
17
legend
S'i!arch Res\Jlts Kmg County
Parcel,;
Li1ke$ <'>rNJ l<1r~ nven,
St•eams
f~lj;l;f!(l
Dralnageb!IS<rnl
Symbol Drainage
Component Type,
Name and SIH
l)J*lh .. tlb#,Nllill,. ---~*· J)Ofld;Slze:!lamttler. .. ~--
(!) 11.· CMP
6) ,,z.· CMP
(J) •'-. C"'-.r'
(f) >."CMD
& C,.cJ.. R
® 1-.S'P'"' -"--~ .... ~
lp,:,...£.R-11~.-....
I?) ,-.. ..... c .. ~ .....
~ J...
Figure 3.5
Offsite Analysis Drainage System Table
OFF--&m ANALYSJS DRAINAG~ SYSttM TABLE
SURFACE WATER DESIGN MANUAL, CORE. REQUIREMENT #l
Subbasi• Name: Snbba:dn Numbtr:
°"''-Slopo Di•....,. .. _
Pot»ntlal Obsefvatlona of field
Component from site Problem& Problems inspector, reaoutc•
Dftcrio"°" disdtU"II reviewer or resident ---. ~1111.,1.UOII, ~Ut'dll<UipKl!y.~. ~~~~ -.deplh.t.,,...al1lllbllllw
r-JiA
~lioodng.hllrlllalllol"~ --~~~~-
C. .... L,,ul:; 0,, -s,.,.,. ,/ .. ,{,,-/,
!!_..._/ V>lc1' t: I \,,,.,,,,..;..,t.,.
(..,.f,u~r:: / ~.
~ .. ,;:.O,.t-._vi
i--, ".,__.,.,_(. I .-t,-.
h"ol•• ~-,i., •. J,.· :ll
5"60'
)""'<00'
19
Figure 3.6
Picture from Point #1 Looking north along 1161h Ave SE
20
Figure 3.7
Picture from Point #2 Looking north along 1161h Ave SE
'II' , .. ->,
The 12" CMP culvert was almost completely covered with vegetation
21
Figure 3.8
Picture from Point #3 Looking north. along 1161h Ave SE
The 12" CMP culvert was covered with vegetation under the driveway.
22
Flows from the ditch enter the culvert and are piped into the storm drain system from this
location. The culvert was covered with litter and vegetation.
23
Figure 3.10
Picture from Point #5 Looking west alon
24
Figure 3.11
Picture from Point #6 Looking east along SE 176th St (Petrovitsky)
The manhole cover shown in the crosswalk is estimated to be the point of convergence
between the 116th Ave SE and SE 176th St storm drains. From there it's piped to Big
Soos Creek.
25
Figure 3.12
Picture from Point #7 Looking east along SE 1761" St (Petrovitsky)
. ~~ '
The estimated discharge location of the project site's storm water, approximately 1300
feet downstream of the project site.
26
4. FLOW CONTROL & WATER QUALITY FACILITY ANALYSIS AND
DESIGN
4.1 Existing Site Hydrology
The existing site consists of 1 single-family dwelling with associated driveway and
several detached sheds near the dwelling. The existing site is relatively flat (mean slope
of 5.5%, less than 10% max slopes on site) with a slope from the southwest to the
northeast comers of the project site. The pervious portions of the parcel are generally
pasture.
According to the GER by RGI the soils onsite include loose to very dense silty sand with
gravel. See Figure 1.4 for the Soils Map. This report shows that the site is generally
underlain with Till soils, which are incapable of infiltration. Therefore Till soils are used in
the KCRTS model, with the predeveloped area being modeled as Till Forest.
Due to the existing site slope, the site will flow toward the northeast corner of the
property. These flows converge about 200 feet downstream of the project site at the
intersection of SE Petrovitsky and 116th Ave SE.
The predeveloped basin for the project site also includes the frontage improvements.
This area will be improved with a new sidewalk including curb and gutter.
TABLE 4.1
P D I dT re-eve ope ributary Area
SUBBASIN TOTAL AREA TILL FOREST IMPERVIOUS
{Ac) (Ac) (Ac)
Onsite Basin 3.52 3.52 0.00
Bvoass Basin 0.11 0.11 0.00
Offsite Basin 0.11 0 00 0.11
TOTAL 3.74 3.63 0.11
4.2 Developed Site Hydrology
The project will create 17 single family lots with associated roadway, sidewalk,
driveways, roof areas, landscaped yards, and a combined detention/water quality pond
adjacent to an open space tract. All 17 residence lots will have new single-family
dwelling units.
A portion of the frontage improvement area will bypass the pond and be treated as
bypass area. For more information, see Table 4.3 below and Figure 4.1.
The maximum impervious surface area allowed by the City of Renton Zoning Code 4-2-
11 QA for R-8 zoned lots is 65%. However, the site will utilize Flow Control BMP C2.9
Reduced Impervious Surface Credit, and reduce on-site allowable impervious area by
10%. Therefore, building rooftops and impervious areas (driveway, porch, patios) are
modeled as 55% impervious.
27
The combined detention/water quality pond is located in the north eastern corner of the
site. The combined detention/water quality pond will discharge to the east into the
existing 1161h Ave SE system, which is the site's natural discharge location.
TABLE4.2
eve ope on eame D dP dDt' dA rea
SUBBASIN .TOTAL AREA TILL GRASS IMPERVIOUS
(Ac). (Ac) (Ac) :;·i:~-,t
Onsite Basin 3.52 1.21 2.31
Offsite Basin 0.11 0.00 0.11
TOTAL 3.63 1.21 2.42
TABLE4.3
Developed Bypass Area
SUBBASIN TOTAL AREA TILL GRASS IMPERVIOUS
(Ac\ /Ac\ (Ac\
Bypass Basin 0.11 0.00 0.11
TOTAL 0.11 0.00 0.11
See Figure 4.1 for a visual representation of the Developed Tributary Area.
4.3 Performance Standards
Performance Standards for flow control design use the KCRTS Methodology with hourly
time steps as described in Section 4.4 below. Runoff files for the existing, proposed, and
bypass conditions were created using the historic KCRTS time series data sets for the
SeaTac Rainfall Region with a Correction Factor of 1.0.
The site requires basic water quality treatment. Water quality will be satisfied with a
wetpond, which will be located in the combined detention/water quality pond.
4.4 Flow Control System
The pond was sized per the requirements in the 2009 Surface Water Design Manual.
Per the City of Renton's Flow Control Application Map, the project site is in the Flow
Control Duration Standard (Forested Conditions, Level 2) area. This standard requires
the site to match the durations of high flows at their predevelopment levels for all flows
from one-half of the 2 year peak flow up to the 50 year peak flow.
The offsite flows being routed through the pond are not subject to flow control, therefore
the offsite flows will be added to the predeveloped and developed flows.
PreDevFT = PreDev (Onsite +Bypass)+ Offsite (Flow Through)
DevFT = Dev (Onsite) + Offsite (Flow Through)
28
The target flows are calculated as follows:
50% 2 year: 50% of the 2 year from PreDev (Onsite) + Offsite 2 year
50 year: PreDev 50 year + Offsite 50 year
The pond's inflow will be modeled using the DevFT time series and the pond's outflow
will be the RDout time series. This RDout time series plus the Bypass time series will
match the Flow Control Duration Standard (Forested Conditions, Level 2) at the Point of
Compliance 200 feet downstream of the project site.
KCRTS v6.0 was used to design the proposed pond. Procedures and design criteria
specified in the 2009 Surface Water Design Manual were followed for the hydrologic and
hydraulic modeling. The KCRTS pond sizing output is included at the end of this section.
The KCRTS output models the required detention volume as 47,175 cubic feet of
storage, with 8.50 feet of detention. The proposed pond provides 62,109 cubic feet of
storage, which results in a 24% factor of safety.
4.5 Water Quality Facility
The proposed water quality pond for Kinkade Crossing will use the 2009 Surface Water
Design Manual guidance for Basic Menu wetpond(s) that would be sized to a V8Na ratio
of 3.0, which will treat approximately 95 percent of all runoff.
A V8 Na = 3 is calculated by dividing the wetpond volume (V8 ) by the volume of runoff
(Va) from the mean annual storm. The sizing of wetponds is accomplished by
determining the acreage of pervious and impervious land. Runoff volumes from
pervious and impervious areas were determined by multiplying the acreage of each
category by the mean annual storm (0.47 inches). Runoff factors of 0.25 for till grass
areas, 0.10 for till forest areas and 0.90 for impervious areas were utilized. The sum
of these values is the total runoff volume (VR)-The required basin volume or the
volume of the wetpond is determined by multiplying the VR by 3.0.
VR rn G,ass = 1.21 Ac (Table 4.2) x 0.47 in. x 0.25/12 = 0.0118 Acre -feet
VR=lm;er,bus = 2.31 Ac (Table 4.2) x 0.47 in x 0.90/12 = 0.0814 Acre -feet
Total runoff volume VR = VR 1111 Grnss + VR lmpeMous = 0.0933 Acre -feet
Total basin volume Vs= 0.0933 x 3 = O 2798 Acre -feet= 12 189 cubic feet
Wetpond Volume provided= 14 549 cubic feet
The bypass area will not be able to be treated due to topography. The bypass area is
less than 5000 square feet and therefore will not require treatment in accordance with
Core Requirement #8 of the 2009 City of Renton Surface Water Design Manual.
Additionally, the wetpond will not have a till liner, as the existing soils are impermeable
till.
29
Figure 4.1
Pond Tributary Area
30
LEG_EN
-~au-
-----s-
--~·---·W· ---, •••••I
STORM
DETENTION RI
DETENTION Pl
WAT(R QUALi
WATER QUALi
NOTE:
ALL STRUCTl
480
470
460
450
I 1···""
440
PONDC
480 c-----,,--,--
470 i-----++---
450 I .....\, M:='.'.
4501 I.,__
Kinkade Crossing KCRTS Output
Offsite Land Use Condition: ST
0.00 0.00 0.000000
0.00 0.00 0.000000
0.00 0.00 0.000000
0.00 0.00 0.000000
0.00 0.00 0.000000
0.00 0.00 0.000000
0.00 0.00 0.000000
0.11 0.00 0.000000
OffsiteFT.tsf
ST 1.000000
Predeveloped Land Use Condition:
3.63 0.00
0.00 0.00
0.00 0.00
0.00 0.00
0.00 0.00
0.00 0.00
0.00 0.00
0.00 0.00
PreDev.tsf
ST 1.000000
[Al ADD Time Series
PreDevFT.tsf
2
OffsiteE'T.tsf
1.00000
PreDev.tsf
1. 00000
0.00000
0.00000
0.000000
0.000000
0.000000
0.000000
0.000000
0.000000
0.000000
0.000000
Flow Frequency Analysis
Time Series E'ile:PreDevFT.tsf
Project Location:Sea-Tac
Till Forest
Till Pasture
Till Grass
Outwash forest
Outwash Pasture
Outwash Grass
Wetland
Impervious
Till Forest
Till Pasture
Till Grass
Outwash Forest
Outwash Pasture
Outwash Grass
Wetland
Impervious
LogPearson III Coefficients
Mean= -0.982 StdDev= 0.224
Skew= -0.267
---Annual Peak E'low Rates--------E'low Frequency Analysis-------
Flow Rate Rank Time of Peak --Peaks Rank Return Prob
ICE'S) (CFS) Period
0.132 16 2/16/49 22:00 0.281 89.50 0.989
0.251 2 3/03/50 16:00 0.251 2 32.13 0. 969
0.248 3 2/09/51 18:00 0.248 3 19.58 0.949
0.090 33 1/30/52 8:00 0.239 4 14.08 0.929
0.069 43 1/18/53 19:00 0.236 5 10.99 0.909
0.093 28 1/22/54 20:00 0.200 6 9.01 0.889
0.159 11 2/07/55 21: 00 0.196 7 7.64 0.869
0.147 14 12/20/55 17: 00 0.175 8 6.63 0.849
0.122 18 12/09/56 14:00 0.169 9 5.86 0.829
0 .114 21 1/16/58 17: 00 0.169 10 5.24 0.809
0.093 29 1/24/59 1: 00 0 .159 11 4.75 0.789
0.175 8 11/20/59 21:00 0.156 12 4.34 0.769
0.092 31 2/24/61 15:00 0.148 13 3.99 0.749
0.063 44 1/02/62 22:00 0.147 14 3.70 0.729
0.083 37 12/15/62 2:00 0.141 15 3.44 0.709
0.097 26 1/01/64 14:00 0.132 16 3.22 0.690
0.070 41 11/30/64 7:00 0.124 17 3.03 0.670
0.085 36 1/05/66 16:00 0.122 18 2.85 0.650
0.169 9 1/19/67 14:00 0.121 19 2.70 0.630
0.102 22 2/03/68 22:00 0.118 20 2.56 0.610
0.101 23 12/03/68 17:00 0 .114 21 2.44 0.590
0.093 30 1/13/70 23:00 0.102 22 2.32 0.570
0.079 40 12/06/70 8:00 0.101 23 2.22 0.550
0.200 6 2/28/72 3:00 0.099 24 2.13 0.530
0.091 32 1/13/73 5:00 0.098 25 2.04 0.510
0.099 24 1/15/74 2:00 0.097 26 1. 96 0. 4 90
0.156 12 12/26/74 23:00 0.094 27 1. 89 0.470
0.098 25 12/02/75 20:00 0.093 28 1. 82 0.450
0.029 50 8/26/77 2:00 0.093 29 1. 75 0.430
0.089 34 12/10/77 17:00 0.093 30 1. 70 0.410
0.049 46 2/12/79 7:00 0.092 31 1. 64 0.390
0 .118 20 12/15/79 8:00 0.091 32 1. 59 0.370
0.080 39 12/26/80 0:00 0.090 33 1. 54 0.350
0.148 13 10/06/81 15:00 0.089 34 1. 49 0.330
0.121 19 1/05/83 8:00 0.086 35 1. 45 0.310
0.083 38 1/03/84 1:00 0.085 36 1. 41 0. 291
0.044 47 2/11/85 3:00 0.083 37 1. 37 0. 271
0 .196 7 1/18/86 20:00 0.083 38 1. 33 0.251
0 .169 10 11/24/86 4:00 0.080 39 1. 30 0.231
0.070 42 1/14/88 12:00 0.079 40 1. 27 0. 211
0.042 48 12/30/88 5:00 0.070 41 1.24 0.191
0.281 1 1/09/90 9:00 0.070 42 1. 21 0 .171
0.236 5 4/05/91 2:00 0.069 43 1.18 0.151
0. 094 27 1/27/92 17:00 0.063 44 1.15 0 .131
0.086 35 3/22/93 23:00 0.060 45 1.12 0 .111
0.031 49 2/17/94 18:00 0.049 46 1.10 0.091
0.124 17 2/19/95 18:00 0.044 47 1. 08 0.071
0.239 4 2/09/96 1:00 0.042 48 1.05 0.051
0.141 15 1/02/97 6:00 0.031 49 1.03 0.031
0.060 45 10/30/97 7:00 0. 029 50 1.01 0. 011
Computed Peaks 0.312 100.00 0.990
Computed Peaks 0. 279 50.00 0.980
Computed Peaks 0.245 25.00 0. 960
Computed Peaks 0.198 10.00 0.900
Computed Peaks 0.188 8.00 0.875
Computed Peaks 0.162 5.00 0.800
Computed Peaks 0.107 2.00 0.500
Computed Peaks 0.071 1. 30 0.231
Developed Land Use Condition:
0.00 0.00 0.000000
0.00 0.00 0.000000
Dev.tsf
1. 21
0.00
0.00
0.00
0.00
2.30
0.00
0.00
0.00
0.00
0.00
0.00
ST 1. 000000
[A] ADD Time Series
DevFT.tsf
2
Dev.tsf
1. 00000 0.00000
OffsiteFT.tsf
1. 00000 0.00000
0.000000
0.000000
0.000000
0.000000
0.000000
0.000000
Flow Frequency Analysis
Time Series File:devft.tsf
Project Location:Sea-Tac
Till Forest
Till Pasture
Till Grass
Outwash Forest
Outwash Pasture
Outwash Grass
Wetland
Impervious
LogPearson III
Mean= -0.160
Skew=
Coefficients
StdDev= 0.107
0.449
---Annual Peak Flow Rates--------Flow Frequency Analysis-------
Flow Rate Rank Time of Peak --Peaks Rank Return Prob
(CFS) (CFS) Period
0.706 21 2/16/49 21: 00 1. 23 1 89.50 0.989
1. 15 2 3/03/50 16:00 1.15 2 32.13 0. 969
0.716 20 2/09/51 2:00 1.13 3 19.58 0.949
0.573 40 10/15/51 13:00 1. 13 4 14.08 0. 929
0.543 44 3/24/53 15:00 0.990 5 10.99 0.909
0.658 27 12/19/53 19:00 0.989 6 9.01 0.889
0.682 23 11/25/54 2:00 0.906 7 7.64 0.869
0.666 24 11/18/55 15:00 0.880 8 6.63 0.849
0.783 15 12/09/56 14:00 0.879 9 5.86 0.829
0.694 22 12/25/57 16:00 0.834 10 5.24 0.809
0.518 47 11/18/58 13:00 0. 813 11 4.75 0.789
0.666 25 11/20/59 5:00 0.810 12 4.34 0.769
0.591 36 2/14/61 21: 00 0.807 13 3.99 0.749
0.587 38 11/22/61 2:00 0.797 14 3.70 0. 729
0.589 37 12/15/62 2:00 0.783 15 3.44 0.709
0.662 26 12/31/63 23:00 0. 776 16 3.22 0.690
0.595 35 12/21/64 4:00 0.769 17 3.03 0.670
0.597 34 1/05/66 16:00 0.759 18 2.85 0.650
0.906 7 11/13/66 19:00 0.743 19 2.70 0.630
0.989 6 8/24/68 16:00 0.716 20 2.56 0. 610
0.544 43 12/03/68 16:00 0.706 21 2.44 0.590
0.601 33 1/13/70 22:00 0.694 22 2.32 0.570
0.572 41 12/06/70 8:00 0.682 23 2.22 0.550
0.880 8 2/27 /72 7:00 0.666 24 2.13 0.530
0.532 46 1/13/73 2:00 0.666 25 2.04 0.510
0.636 30 11/28/73 9:00 0.662 26 1. 96 0.490
0.834 10 12/26/74 23:00 0.658 27 1. 89 0.470
0.542 45 12/02/75 20:00 0.641 28 1. 82 0. 450
0.641 28 8/2 6/77 2:00 0.637 29 1. 75 0. 430
0.879 9 9/17 /78 2:00 0.636 30 1. 70 0.410
0.776 16 9/08/79 15:00 0.623 31 1. 64 0. 390
0.769 17 12/14/79 21:00 0.623 32 1. 59 0.370
0.813 11 11/21/80 11: 00 0.601 33 1. 54 0.350
1.13 3 10/06/81 0:00 0.597 34 1. 49 0.330
0.807 13 10/28/82 16:00 0.595 35 1. 45 0.310
0.637 29 1/03/84 1:00 0.591 36 1. 41 0. 291
0.553 42 6/06/85 22:00 0.589 37 1. 37 0.271
0.759 18 1/18/86 16:00 0.587 38 1. 33 0.251
0.990 5 10/2 6/86 0:00 0.577 39 1. 30 0.231
0.445 49 11/11/87 0:00 0.573 40 1. 27 0 .211
0.577 39 8/21/89 17:00 0.572 41 1. 24 0.191
1. 23 1 1/09/90 6:00 0.553 42 1. 21 0.171
1.13 4 11/24/90 8:00 0.544 43 1.18 0.151
0.623 32 1/27/92 15:00 0.543 44 1.15 0.131
0. 413 50 11/01/92 16:00 0.542 45 1.12 0.111
0.478 48 11/30/93 22:00 0.532 46 1.10 0. 091
0.623 31 11/30/94 4:00 0.518 47 1. 08 0.071
0. 797 14 2/08/96 10:00 0.478 48 1. 05 0.051
0.743 19 1/02/97 6:00 0.445 49 1. 03 0.031
0.810 12 10/04/97 15:00 0.413 50 1. 01 0. 011
Computed Peaks 1. 33 100.00 0.990
Computed Peaks 1. 21 50.00 0.980
Computed Peaks 1.10 25.00 0. 960
Computed Peaks 0.956 10.00 0.900
Computed Peaks 0.927 8.00 0.875
Computed Peaks 0.844 5.00 0.800
Computed Peaks 0.679 2.00 0.500
Computed Peaks 0. 571 1. 30 0.231
Bypass Land Use Conditions:
0.00 0.00 0.000000 Till Forest
0.00 0.00 0.000000 Till Pasture
0.00 0.00 0.000000 Till Grass
0.00 0.00 0.000000 Outwash Forest
0.00 0.00 0.000000 Outwash Pasture
0.00 0.00 0.000000 Outwash Grass
0.00 0.00 0.000000 Wetland
0.11 0.00 0.000000 Impervious
Bypass.tsf
ST 1.000000
Flow Frequency Analysis LogPearson III Coefficients
Time Series File:Bypass.tsf Mean= -1. 477 StdDev= 0.095
Project Location:Sea-Tac Skew= 0. 572
---Annual Peak Flow Rates--------Flow Frequency Analysis-------
Flow Rate Rank Time of Peak --Peaks Rank Return Prob
(CFS) (CFS) Period
0.033 20 2/16/49 21:00 0.054 1 89.50 0.989
0.048 6 3/03/50 16:00 0.053 2 32 .13 0. 969
0.032 25 2/09/51 2:00 0.050 3 19.58 0.949
0.029 33 10/15/51 13:00 0.050 14.08 0.929
0.027 43 3/24/53 15:00 0.049 5 10.99 0.909
0.031 28 12/19/53 19:00 0.048 6 9.01 0.889
0.033 22 11/25/54 2:00 0.045 7 7.64 0.869
0.033 24 11/18/55 15:00 0.043 8 6.63 0.849
0.036 15 12/09/56 14:00 0.041 9 5. 86 0.829
0.033 21 12/25/57 16:00 0.040 10 5.24 0.809
0.026 47 11/03/58 17:00 0.040 11 4.75 0.789
0.032 27 11/20/59 5:00 0.039 12 4.34 0.769
0.028 39 2/14/61 21:00 0.038 13 3.99 0.749
0.029 36 11/22/61 2:00 0.038 14 3.70 0.729
0.028 42 12/15/62 2:00 0.036 15 3.44 0.709
0.032 26 12/31/63 23:00 0.036 16 3.22 0.690
0.029 35 12/21/64 4:00 0.035 17 3.03 0.670
0.028 38 1/05/66 16:00 0.035 18 2.85 0.650
0.043 8 11/13/66 19:00 0.034 19 2.70 0.630
0.049 5 8/24/68 16:00 0.033 20 2.56 0.610
0.026 44 12/03/68 16:00 0.033 21 2.44 0. 590
0. 029 37 1/13/70 22:00 0.033 22 2.32 0.570
0.028 40 12/05/70 9:00 0.033 23 2.22 0.550
0.040 11 12/08/71 18:00 0.033 24 2.13 0.530
0. 026 45 1/13/73 2:00 0.032 25 2.04 0.510
0.029 34 11/28/73 9:00 0.032 26 1. 96 0. 490
0.038 13 12/26/74 23:00 0.032 27 1. 89 0.470
0. 026 46 11/13/75 19:00 0.031 28 1. 82 0.450
0.033 23 8/26/77 2:00 0.031 29 1. 75 0.430
0.045 7 9/17 /78 2:00 0.031 30 1. 70 0. 410
0.041 9 9/08/79 15:00 0.030 31 1. 64 0.390
0.036 16 12/14/79 21:00 0.030 32 1. 59 0.370
0.039 12 11/21/80 11: 00 0.029 33 1. 54 0.350
0.054 1 10/06/81 0:00 0.029 34 1. 49 0.330
0.040 10 10/28/82 16:00 0.029 35 1. 45 0.310
0.030 31 1/03/84 1:00 0.029 36 1. 41 0.291
0.028 41 6/06/85 22:00 0.029 37 1. 37 0.271
0.035 18 1/18/86 16:00 0.028 38 1. 33 0.251
0.050 3 10/26/86 0:00 0.028 39 1. 30 0.231
0.024 49 11/11/87 0:00 0.028 40 1. 27 0 .211
0.031 29 8/21/89 17:00 0.028 41 1.24 0.191
0.053 2 1/09/90 6:00 0.028 42 1.21 0.171
0.050 4 11/24/90 8:00 0.027 43 1.18 0.151
0.030 32 1/27 /92 15:00 0. 026 44 1.15 0.131
0.022 50 11/01/92 16:00 0. 026 45 1.12 0 .111
0.025 48 9/03/94 10:00 0. 026 46 1.10 0.091
0.031 30 11/30/94 4:00 0.026 47 1. 08 0.071
0.035 17 2/08/96 10:00 0.025 48 1. 05 0.051
0.034 19 1/02/97 6:00 0.024 49 1. 03 0.031
0.038 14 10/04/97 15:00 0.022 50 1. 01 0. 011
Computed Peaks 0.061 100.00 0.990
Computed Peaks 0.056 50.00 0.980
Computed Peaks 0.051 25.00 0. 960
Computed Peaks 0.045 10.00 0.900
Computed Peaks
Computed Peaks
Computed Peaks
Computed Peaks
0.043
0.040
0.033
0.028
Flows used for Target Duration Curve Calculation:
50% of 2 year PreDevFT.pks ~ 0.107 / 2 ~ 0.0535 CFS
-> First Interval Value~ 0.0535 CFS
50 year flow: 50 year PreDevFT.pks ~ 0.279
(50 year flow -First Interval Value) / 35
-> Interval Size~ 0.0064 CFS
0.0064 CFS
Retention/Detention Facility
Type of Facility: Detention Pond
Side Slope: 0.00 H: lV
Pond Bottom Length: 100.00 ft
Pond Bottom Width: 55.50 ft
Pond Bottom Area: 5550. sq. ft
Top Area at 1 ft. FB: 5550. sq. ft
0.127 acres
Effective Storage Depth: 8.50 ft
Stage O Elevation: 0.00 ft
Storage Volume: 47175. cu. ft
1.083 ac-ft
Riser Head:
Riser Diameter:
Number of orifices:
Orifice # Height
(ft)
1 0.00
2 5.30
3 7.20
8.50
12.00
3
Diameter
(in)
0.88
1. 50
1. 50
Top Notch Weir: None
Outflow Rating Curve: None
ft
inches
Full Head
Discharge
(CFS)
0.061
0.109
0.070
Pipe
Diameter
(in)
4. 0
4. 0
8.00
5.00
2.00
1. 30
Stage Elevation Storage Discharge Percolation
Area
(ft) (ft) (cu. ft) (ac-ft) (cfs) (cfs)
ft)
0.00 0.00 0. 0.000 0.000 0.00
5550.
0.01 0.01 56. 0.001 0.002 0.00
5550.
0.875
0.800
0.500
0.231
Surf
(sq.
0.02 0.02 111. 0.003 0.003 0.00
5550.
0.03 0.03 167. 0.004 0.003 0.00
5550.
0.04 0.04 222. 0.005 0.004 0.00
5550.
0.05 0.05 278. 0.006 0.005 0.00
5550.
0.06 0.06 333. 0.008 0.005 0.00
5550.
0.07 0.07 389. 0.009 0.006 0.00
5550.
0.24 0.24 1332. 0.031 0.010 0.00
5550.
0.41 0.41 2276. 0.052 0.013 0.00
5550.
0.57 0.57 3164. 0.073 0.016 0.00
5550.
0.74 0.74 4107. 0.094 0.018 0.00
5550.
0.91 0.91 5051. 0 .116 0.020 0.00
5550.
1. 07 1. 07 5939. 0.136 0.022 0.00
5550.
1. 24 1. 24 6882. 0.158 0.023 0.00
5550.
1. 41 1. 41 7826. 0.180 0.025 0.00
5550.
1. 57 1. 57 8714. 0.200 0.026 0.00
5550.
1. 74 1. 74 9657. 0.222 0.027 0.00
5550.
1. 91 1. 91 10601. 0.243 0.029 0.00
5550.
2.07 2.07 11489. 0.264 0.030 0.00
5550.
2.24 2.24 12432. 0.285 0.031 0.00
5550.
2.41 2.41 1337 6. 0.307 0.032 0.00
5550.
2.57 2.57 14264. 0.327 0.033 0.00
5550.
2.74 2.74 15207. 0.349 0.034 0.00
5550.
2.91 2.91 16151. 0. 371 0.035 0.00
5550.
3.07 3.07 17039. 0.391 0.036 0.00
5550.
3.24 3.24 17982. 0. 413 0.037 0.00
5550.
3.41 3.41 18926. 0.434 0.038 0.00
5550.
3.57 3.57 19814. 0.455 0.039 0.00
5550.
3.74 3.74 20757. 0. 477 0.040 0.00
5550.
3.91 3.91 21701. 0.498 0.041 0.00
5550.
4.07 4.07 22589. 0.519 0.042 0.00
5550.
4.24 4.24 23532. 0.540 0.043 0.00
5550.
4.41 4.41 24476. 0.562 0.044 0.00
5550.
4.57 4.57 25364. 0.582 0.044 0.00
5550.
4.74 4.74 26307. 0.604 0.045 0.00
5550.
4.91 4.91 27251. 0. 626 0. 046 0.00
5550.
5.07 5.07 28139. 0.646 0.047 0.00
5550.
5.24 5.24 29082. 0.668 0.048 0.00
5550.
5.30 5.30 29415. 0.675 0.048 0.00
5550.
5.32 5.32 29526. 0.678 0.048 0.00
5550.
5.33 5.33 29582. 0.679 0.050 0.00
5550.
5.35 5.35 29693. 0.682 0.052 0.00
5550.
5.36 5.36 29748. 0.683 0.055 0.00
5550.
5.38 5.38 29859. 0.685 0.060 0.00
5550.
5.39 5.39 29915. 0.687 0.065 0.00
5550.
5.41 5.41 30026. 0.689 0.068 0.00
5550.
5.43 5.43 30137. 0.692 0.070 0.00
5550.
5.59 5.59 31025. 0.712 0.082 0.00
5550.
5.76 5.76 31968. 0.734 0. 091 0.00
5550.
5.93 5.93 32 912. 0.756 0.099 0.00
5550.
6.09 6.09 33800. 0. 776 0.106 0.00
5550.
6.26 6.26 34743. 0.798 0.112 0.00
5550.
6.42 6.42 35631. 0.818 0 .117 0.00
5550.
6.59 6. 59 36575. 0.840 0.123 0.00
5550.
6.76 6. 76 37518. 0. 861 0.128 0.00
5550.
6.92 6.92 38406. 0.882 0.132 0.00
5550.
7.09 7.09 39350. 0.903 0 .137 0.00
5550.
7.20 7.20 39960. 0.917 0.140 0.00
5550.
7.22 7.22 40071. 0.920 0.141 0.00
5550.
7.23 7.23 40127. 0.921 0.142 0.00
5550.
7.25 7.25 40238. 0.924 0.145 0.00
5550.
7. 26 7. 26 4 02 93. 0.925 0.149 0.00
5550.
7.28 7.28 40404. 0.928 0.153 0.00
5550.
7.29 7.29 40460. 0. 929 0.159 0.00
5550.
7.31 7.31 40571. 0.931 0.163 0.00
5550.
7.33 7.33 40682. 0.934 0 .165 0.00
5550.
7.49 7. 49 41570. 0.954 0.180 0.00
5550.
7.66 7.66 42513. 0.976 0.193 0.00
5550.
7.82 7.82 43401. 0. 996 0.203 0.00
5550.
7.99 7.99 44345. 1. 018 0 .213 0.00
5550.
8.16 8.16 45288. 1. 040 0 .222 0.00
5550.
8.33 8.33 46232. 1. 061 0.231 0.00
5550.
8.49 8.49 47120. 1.082 0.239 0.00
5550.
8.50 8.50 47175. 1. 083 0.239 0.00
5550.
8.60 8.60 47730. 1. 096 0.552 0.00
5550.
8.70 8.70 48285. 1.108 1.120 0.00
5550.
8.80 8.80 48840. 1.121 1.850 0.00
5550.
8.90 8.90 49395. 1.134 2.650 0.00
5550.
9.00 9.00 49950. 1.147 2.940 0.00
5550.
9.10 9.10 50505. 1.159 3.200 0.00
5550.
9.20 9.20 51060. 1.172 3.430 0.00
5550.
9.30 9.30 51615. 1.185 3.660 0.00
5550.
9.40 9.40 52170. 1.198 3.870 0.00
5550.
9.50 9.50 52725. 1.210 4.060 0.00
5550.
9.60 9.60 53280. 1. 223 4.250 0.00
5550.
9.70 9.70 53835. 1. 236 4.430 0.00
5550.
9.80 9.80 54390. 1. 249 4.610 0.00
5550.
9.90 9.90 54945. 1. 261 4. 770 0.00
5550.
10.00 10.00 55500. 1. 274 4.930 0.00
5550.
10.10 10 .10 56055. 1. 287 5.090 0.00
5550.
10.20 10.20 56610. 1. 300 5.240 0.00
5550.
10.30 10.30 57165. 1. 312 5.380 0.00
5550.
10.40 10. 40 57720. 1. 325 5.530 0.00
5550.
Hyd Inflow Outflow Peak Storage
Stage Elev (Cu-Ft) (Ac-Ft)
1 0.72 0.23 8.31 8.31 46097. 1.058
2 0.80 0.22 8.14 8.14 45199. 1.038
3 1.23 0.21 7.90 7.90 43855. 1. 007
4 0.88 0 .17 7.44 7.44 41265. 0.947
5 0.77 0.17 7.37 7.37 40918. 0.939
6 1.13 0.13 6.70 6.70 37193. 0.854
7 0.83 0.04 4.41 4.41 24455. 0.561
8 0.66 0.04 2.95 2.95 16351. 0.375
Hyd R/D Facility Tributary Reservoir POC Outflow
Outflow Inflow Inflow Target Cale
1 0.23 0.03 ******** ******* 0.24
2 0.22 0.04 ******** ******* 0.23
3 0.21 0.05 ******** ******* 0.22
4 0 .17 0.04 ******** ******* 0.18
5 0.17 0.04 ******** ******* 0.18
6 0 .13 0.05 ******** 0.05 0.15
7 0.04 0.04 ******** ******* 0.07
8 0.04 0.03 ******** ******* 0.06
----------------------------------
Route Time Series through Facility
Inflow Time Series File:devft.tsf
Outflow Time Series File:rdout
POC Time Series File:dsout
Inflow/Outflow Analysis
Peak Inflow Discharge:
Peak Outflow Discharge:
1.23 CFS at 6:00 on Jan 9 in 1990
0.285 CFS at 20:00 on Feb 9 in 1951
Peak Reservoir Stage:
Peak Reservoir Elev:
8. 52 Ft
8. 52 Ft
Peak Reservoir Storage: 47258. Cu-Ft
1.085 Ac-Ft
Add Time Series:bypass.tsf
Peak Summed Discharge: 0. 291 CFS at 20: 00 on Feb 9 in 1951
Point of Compliance File:dsout.tsf
Flow Frequency Analysis
Time Series File:rdout.tsf
Project Location:Sea-Tac
---Annual
Flow Rate
(CFS)
0.044
0.100
0.285
0.039
0.089
0.047
0.044
0.125
0.046
0.084
0.044
0.186
0 .114
0.039
0. 071
0.100
0.115
0.048
0. 096
0.048
0.047
0.087
0.070
0.176
0.121
0.073
0.044
0.047
0.036
0.099
0.035
0.171
0.059
0.138
0.068
0.039
0.041
0.104
0.168
Peak Flow Rates---
Rank Time of Peak
39
17
1
44
22
34
36
11
35
24
37
5
15
46
26
18
14
30
20
31
33
23
27
6
12
25
38
32
48
19
49
7
29
10
28
45
41
16
8
2/22/49
3/05/50
2/09/51
2/04/52
1/18/53
1/07/54
2/08/55
1/06/56
2/26/57
1/17/58
1/24/59
11/21/59
11/24/60
12/24/61
11/30/62
11/19/63
12/01/64
1/07/66
12/13/66
1/20/68
12/11/68
1/27 /70
12/07 /70
3/06/72
12/26/72
1/18/74
12/27 /74
12/04/75
8/26/77
12/15/77
2/12/79
12/17/79
12/30/80
10/06/81
1/08/83
12/10/83
11/04/84
1/19/86
11/24/86
13: 00
6:00
20:00
7:00
21: 00
21:00
10:00
11:00
5:00
7:00
16:00
3:00
11:00
6:00
18:00
16:00
2:00
4:00
11:00
21:00
10:00
3:00
11: 00
22:00
6:00
18:00
12:00
4:00
7:00
18:00
18:00
20:00
22:00
18:00
3:00
19:00
8:00
0:00
8:00
LogPearson III Coefficients
Mean~ -1.118 StdDev~ 0.261
Skew~ 0.392
-----Flow Frequency Analysis-------
--Peaks --Rank Return Prob
(CFS) (ft) Period
0.285 8.51 1 89.50 0.989
0.227 8.25 2 32.13 0.969
0.208 7.90 3 19.58 0.949
0.189
0.186
0.176
0.171
0.168
0.163
0.138
0.125
0.121
0.116
0 .115
0 .114
0.104
0.100
0.100
0.099
0. 096
0.090
0.089
0.087
0.084
0.073
0.071
0.070
0.068
0.059
0.048
0.048
0.047
0.047
0.047
0.046
0.044
0.044
0.044
0.044
7.61
7.57
7.45
7.40
7.36
7.31
7 .11
6.66
6.54
6.38
6.35
6.33
6.05
5.95
5.95
5.92
5.87
5.75
5.73
5.69
5.62
5.47
5.44
5.43
5.41
5.38
5.30
5.18
5 .11
5.08
5.02
4.87
4. 59
4.48
4.42
4.37
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
14.08
10.99
9.01
7.64
6.63
5.86
5.24
4.75
4.34
3.99
3.70
3.44
3.22
3.03
2.85
2.70
2.56
2.44
2.32
2.22
2.13
2.04
1. 96
1. 89
1. 82
1. 75
1. 70
1. 64
1. 59
1. 54
1. 49
1. 45
1. 41
1. 37
1. 33
1. 30
0.929
0.909
0. 88 9
0.869
0.849
0.829
0.809
0.789
0. 769
0.749
0.729
0.709
0.690
0.670
0.650
0.630
0.610
0.590
0.570
0.550
0.530
0.510
0.490
0.470
0.450
0. 430
0.410
0.390
0.370
0.350
0.330
0.310
0.291
0. 271
0.251
0.231
0.044 40 12/10/87 8:00 0.044 4.37 40 1. 27 0 .211
0.040 42 11/05/88 22:00 0.041 3.93 41 1. 24 0.191
0.208 3 1/09/90 12:00 0.040 3.79 42 1. 21 0 .171
0.189 11/24/90 16:00 0.040 3.77 43 1.18 0.151
0.090 21 1/31/92 6:00 0.039 3.59 44 1.15 0 .131
0.038 47 1/26/93 4:00 0.039 3.58 45 1.12 0 .111
0.034 50 2/17 /94 22:00 0.039 3.57 46 1.10 0.091
0 .116 13 12/27 /94 7:00 0.038 3.38 47 1. 08 0. 071
0.227 2 2/09/96 3:00 0.036 3.09 48 1. 05 0.051
o. 163 9 1/02/97 12:00 0.035 2.97 49 1. 03 0.031
0.040 43 1/25/98 0:00 0.034 2.77 50 1. 01 0. 011
Computed Peaks 0.366 8.54 100.00 0.990
Computed Peaks 0. 296 8.52 50.00 0.980
Computed Peaks 0.235 8.42 25.00 0. 960
Computed Peaks 0.168 7.36 10.00 0.900
Computed Peaks 0.156 7.28 8.00 0.875
Computed Peaks 0.124 6.64 5.00 0.800
Computed Peaks 0.073 5.47 2.00 0.500
Computed Peaks 0.048 5.21 1. 30 0.231
Flow Frequency Analysis Log Pear son I II Coefficients
Time Series File:dsout.tsf Mean= -1.037 StdDev~ 0.206
Project Location:Sea~Tac Skew~ 0.672
---Annual Peak Flow Rates--------Flow Frequency Analysis-------
Flow Rate Rank Time of Peak --Peaks Rank Return Prob
(CFS) (CFS) Period
0.066 35 2/16/49 21:00 0.291 1 89 .50 0.989
0.104 19 3/05/50 4:00 0.238 2 32.13 o. 969
0.291 1 2/09/51 20:00 0.218 3 19.58 0.949
0.054 45 1/30/52 8:00 0.196 14.08 0.929
0. 096 21 1/18/53 19:00 0.193 5 10.99 0.909
0.062 39 12/19/53 19:00 0.183 6 9.01 0.889
0.069 31 11/25/54 2:00 0.178 7 7.64 0.869
0.133 11 1/06/56 9:00 0.173 8 6.63 0.849
0.070 30 12/09/56 14:00 0.167 9 5.86 0.829
0.087 24 1/17/58 6:00 0.164 10 5.24 0.809
0.065 36 1/26/59 20:00 0.133 11 4.75 0.789
0.193 5 11/21/59 1:00 0.129 12 4.34 0.769
0.126 13 11/24/60 8:00 0.126 13 3.99 0.749
0.054 46 12/22/61 17:00 0.123 14 3.70 0. 729
0.074 27 11/30/62 17:00 0.122 15 3.44 0.709
0.106 17 11/19/63 15:00 0.111 16 3.22 0.690
0.122 15 12/01/64 6:00 0.106 17 3.03 0.670
0.069 33 1/05/66 16:00 0.105 18 2.85 0.650
0.099 20 12/13/66 10:00 0.104 19 2.70 0.630
0.069 34 8/24/68 16:00 0.099 20 2.56 0.610
0.060 40 12/03/68 16:00 0. 096 21 2.44 0.590
0.091 23 1/27 /70 1:00 0.095 22 2.32 0.570
0. 072 28 12/07 /70 10:00 0.091 23 2.22 0.550
0.183 6 3/06/72 21:00 0.087 24 2.13 0.530
0.129 12 12/26/72 3:00 0. 076 25 2.04 0.510
0.076 25 1/18/74 16:00 0.074 26 1. 96 0. 490
0.074 26 12/26/74 23:00 0.074 27 1. 89 0.470
0.060 41 12/02/75 20:00 0.072 28 1. 82 0.450
0.065 37 8/26/77 2:00 0.071 29 1. 75 0.430
0.105 18 12/15/77 16:00 0.070 30 1. 70 0.410
0.051 48 9/08/79 15:00 0.069 31 1. 64 0.390
0.178 7 12/17 /79 19:00 0.069 32 1. 59 0.370
0.069 32 11/21/80 11:00 0.069 33 1. 54 0.350
0 .164 10 10/06/81 15:00 0.069 34 1. 49 0.330
0. 071 29 1/08/83 2:00 0.066 35 1. 45 0.310
0.057 44 1/03/84 1:00 0.065 36 1. 41 0 .291
0.054 47 11/03/84 11:00 0.065 37 1. 37 0.271
0 .111 16 1/18/86 21:00 0.065 38 1. 33 0.251
0.173 8 11/24/86 7:00 0.062 39 1. 30 0.231
0.059 43 12/09/87 16:00 0.060 40 1. 27 0. 211
0.060 42 11/05/88 14:00 0.060 41 1. 24 0.191
0.218 3 1/09/90 10:00 0.060 42 1. 21 0.171
0 .196 4 11/24/90 15:00 0.059 43 1.18 0.151
0.095 22 1/31/92 5:00 0.057 44 1. 15 0.131
0.048 49 3/22/93 22:00 0.054 45 1.12 0 .111
0.048 50 2/17 /94 18:00 0.054 46 1.10 0.091
0.123 14 12/27/94 5:00 0. 054 47 1. 08 0. 071
0.238 2 2/09/96 2:00 0.051 48 1. 05 0.051
0 .167 9 1/02/97 12:00 0.048 49 1. 03 0.031
0.065 38 10/04/97 15:00 0.048 50 1. 01 0. 011
Computed Peaks 0.347 100.00 0.990
Computed Peaks 0.285 50.00 0.980
Computed Peaks 0.232 25.00 0. 960
Computed Peaks 0.172 10.00 0.900
Computed Peaks 0.162 8.00 0.875
Computed Peaks 0.134 5.00 0.800
Computed Peaks 0.087 2.00 0.500
Computed Peaks 0.063 1. 30 0.231
Flow Duration from Time Series File:rdout.tsf
Cutoff Count Frequency CDF Exceedence Probability
CFS ?o
0.004 210961 48.165 48.165 51.835 0.518E+OO
0.012 69673 15.907 64. 072 35.928 0.359E+OO
0.020 56387 12.874 76.945 23.055 0.231E+OO
0.028 46826 10.691 87.636 12.364 0.124E+OO
0.036 31418 7.173 94.809 5.191 0.519E-01
0.044 16092 3.674 98.483 1. 517 0.152E-01
0.052 4543 1. 037 99.521 0. 479 0.479E-02
0.060 161 0.037 99.557 0.443 0.443E-02
0.068 140 0.032 99.589 0. 411 0.411E-02
0.076 308 0.070 99.660 0.340 0.340E-02
0.084 243 0.055 99.715 0.285 0.285E-02
0.092 242 0.055 99.770 0.230 0.230E-02
0.100 238 0.054 99.825 0.175 0.175E-02
0.108 170 0.039 99.863 0 .137 0.137E-02
0.116 173 0.039 99.903 0.097 0.970E-03
0.124 124 0.028 99.931 0.069 0.687E-03
0.132 92 0.021 99.952 0.048 0.477E-03
0.140 81 0.018 99.971 0. 029 0.292E-03
0.148 15 0.003 99.974 0.026 0.258E-03
0.156 5 0.001 99.975 0.025 0.247E-03
0.164 12 0.003 99.978 0.022 0.219E-03
0 .172 23 0.005 99.983 0.017 0. l 67E-03
0.180 16 0.004 99.987 0. 013 0 .130E-03
0.188 13 0.003 99.990 0.010 O.lOOE-03
0 .196 8 0.002 99.992 0.008 0.822E-04
0.204 8 0.002 99.994 0.006 0.639E-04
0.212 11 0.003 99. 996 0.004 0.388E-04
0.220 3 0.001 99.997 0.003 0.320E-04
0.228 8 0.002 99.999 0.001 0.137E-04
0.236 3 0.001 99.999 0.001 0.685E-05
0.244 1 0.000 100.000 0.000 0.457E-05
0.252 1 0.000 100.000 0.000 0.228E-05
0.260 0 0.000 100.000 0.000 0.228E-05
0.268 0 0.000 100.000 0.000 0.228E-05
0.276 0 0.000 100.000 0.000 0.228E-05
0.284 0 0.000 100.000 0.000 0.228E-05
Flow Duration from Time Series File:dsout.tsf
Cutoff Count Frequency CDF Exceedence Probability
CFS % %
0.004 210159 47.982 47.982 52.018 0.520E+OO
0.012 68803 15.708 63.690 36.310 0.363E+OO
0.020 55487 12.668 76.358 23.642 0.236E+00
0.029 46466 10.609 86. 967 13. 033 0.130E+OO
0.037 31587 7.212 94. 17 9 5.821 0.582E-01
0.045 16813 3.839 98.017 1.983 0.198E-01
0.053 5729 1. 308 99.325 0.675 0.675E-02
0.061 818 0.187 99.512 0.488 0.488E-02
0.069 290 0.066 99.578 0.422 0.422E-02
0.078 306 0.070 99.648 0.352 0.352E-02
0.086 265 0.061 99.708 0.292 0. 2 92E-02
0. 094 241 0.055 99.763 0.237 0.237E-02
0.102 231 0.053 99.816 0.184 0.184E-02
0 .110 180 0.041 99.857 0.143 0.143E-02
0 .118 164 0.037 99.895 0.105 0.105E-02
0.127 130 0.030 99. 924 0. 07 6 0.756E-03
0.135 104 0.024 99.948 0.052 0.518E-03
0.143 62 0.014 99.962 0.038 0. 377E-03
0.151 34 0.008 99.970 0.030 0.299E-03
0.159 17 0.004 99.974 0. 026 0.260E-03
0.167 14 0.003 99. 977 0.023 0.228E-03
0 .176 24 0.005 99.983 0.017 0.174E-03
0.184 15 0.003 99.986 0.014 0 .139E-03
0 .192 11 0.003 99.989 0. 011 0 .114E-03
0.200 11 0.003 99.991 0.009 0.890E-04
0.208 10 0.002 99.993 0.007 0.662E-04
0.216 8 0.002 99.995 0.005 0.479E-04
0.225 6 0.001 99.997 0.003 0.342E-04
0.233 4 0.001 99.997 0.003 0.251E-04
0.241 6 0.001 99.999 0.001 0.114E-04
0.249 2 0.000 99.999 0.001 0.685E-05
0.257 1 0.000 100.000 0.000 0.457E-05
0.265 1 0.000 100.000 0.000 0.228E-05
0.273 0 0.000 100.000 0.000 0.228E-05
0.282 0 0.000 100.000 0.000 0.228E-05
0.290 0 0.000 100.000 0.000 0.228E-05
Duration Comparison Anaylsis
Base File: predevft.tsf
New File: dsout.tsf
Cutoff Units: Discharge in CFS
-----Fraction of Time--------------Check of Tolerance-------
Cutoff Base New %Change Probability Base New %Change
0.053 0.77E-02 0.66E-02 -14.6 I 0.77E-02
0. 071 0.40E-02 0.41E-02 2.3 I 0.40E-02
0.088 0.22E-02 0.27E-02 24.0 I 0.22E-02
0.106 0.13E-02 0.16E-02 27.2 I 0 .13E-02
0.123 0. 77E-03 0.87E-03 12.7 I 0.77E-03
0.141 0.49E-03 0.39E-03 -20.0 I 0.49E-03
0.158 0.32E-03 0.26E-03 -18.6 I 0.32E-03
0 .176 0.21E-03 0 .17E-03 -21.3 I 0.21E-03
0.193 0.12E-03 0. llE-03 -11. 5 I 0.12E-03
0 .211 0.64E-04 0.64E-04 0.0 I 0.64E-04
0.228 0.37E-04 0.30E-04 -18.8 I 0.37E-04
0.246 0.14E-04 0.68E-05 -50.0 I 0.14E-04
0. 263 0.46E-05 0.23E-05 -50.0 I 0.46E-05
0.280 0.23E-05 0.23E-05 0.0 I 0.23E-05
Maximum positive excursion= 0.008 cfs I 9.2%)
occurring at 0.085 cfs on the Base Data:predevft.tsf
and at 0.093 cfs on the New Data:dsout.tsf
Maximum negative excursion= 0.005 cfs I -7.8%)
occurring at 0.061 cfs on the Base Data:predevft.tsf
and at 0.056 cfs on the New Data:dsout.tsf
Route Time Series through Facility
Inflow Time Series File:devft.tsf
Outflow Time Series File:rdout
POC Time Series File:dsout
Inflow/Outflow Analysis
Peak Inflow Discharge: 1.23
Peak Outflow Discharge: 0.285
Peak Reservoir Stage: 8.52
Peak Reservoir Elev: 8.52
Peak Reservoir Storage: 47258.
1. 085
Add Time Series:bypass.tsf
CFS at 6:00 on
CFS at 20:00 on
Ft
Ft
Cu-Ft
Ac-Ft
0.053
0. 071
0.088
0.106
0.123
0.141
0.158
0 .176
0.193
0. 211
0.228
0.246
0.263
0.280
Jan
Feb
Peak Summed Discharge: 0.291 CFS at 20:00 on Feb
0.051
0.072
0. 096
0.113
0.126
0.136
0.148
0.169
0.190
0. 211
0.222
0.237
0 .260
0.290
9 in 1990
9 in 1951
9 in 1951
Point of Compliance File:dsout.tsf
Flow Frequency Analysis
Time Series File:rdout.tsf
Project Location:Sea-Tac
LogPearson III Coefficients
Mean= -1.118 StdDev= 0.261
Skew= 0.392
-4.2
1. 2
9.0
7.0
2.1
-3.6
-6.6
-3.7
-1. 8
0.3
-2.8
-3.3
-1. 0
3.5
---Annual Peak Flow Rates--------Flow Frequency Analysis-------
Flow Rate Rank Time of Peak --Peaks --Rank Return Prob
(CFS) (CFS) (ft) Period
0.044 39 2/22/49 13:00 0.285 8.51 89.50 0.989
0.100 17 3/05/50 6:00 0.227 8.25 2 32.13 0. 969
0.285 1 2/09/51 20:00 0.208 7.90 3 19.58 0.949
0.039 44 2/04/52 7:00 0.189 7.61 4 14.08 0.929
0.089 22 1/18/53 21:00 0.186 7.57 5 10.99 0.909
0.047 34 1/07/54 21:00 0.176 7.45 6 9.01 0.889
0.044 36 2/08/55 10:00 0 .171 7.40 7 7.64 0.869
0.125 11 1/06/56 11:00 0.168 7.36 8 6.63 0.849
0.046 35 2/26/57 5:00 0.163 7.31 9 5. 8 6 0.829
0.084 24 1/17/58 7:00 0.138 7 .11 10 5.24 0.809
0.044 37 1/24/59 16:00 0.125 6.66 11 4.75 0.789
0.186 5 11/21/59 3:00 0.121 6.54 12 4.34 0.769
0 .114 15 11/24/60 11: 00 0.116 6.38 13 3.99 0.749
0.039 46 12/24/61 6:00 0.115 6.35 14 3.70 0. 729
0.071 26 11/30/62 18:00 0.114 6.33 15 3.44 0.709
0.100 18 11/19/63 16:00 0.104 6.05 16 3.22 0.690
0 .115 14 12/01/64 2:00 0.100 5.95 17 3.03 0.670
0.048 30 1/07/66 4:00 0.100 5.95 18 2.85 0.650
0. 096 20 12/13/66 11: 00 0.099 5.92 19 2.70 0.630
0.048 31 1/20/68 21:00 0. 096 5.87 20 2.56 0.610
0.047 33 12/11/68 10:00 0.090 5.75 21 2.44 0.590
0.087 23 1/27 /70 3:00 0.089 5.73 22 2.32 0.570
0.070 27 12/07 /70 11: 00 0.087 5.69 23 2.22 0.550
0.176 6 3/06/72 22:00 0.084 5.62 24 2.13 0.530
0.121 12 12/26/72 6:00 0.073 5.47 25 2.04 0.510
0.073 25 1/18/74 18:00 0.071 5.44 26 1. 96 0.490
0.044 38 12/27 /74 12:00 0.070 5.43 27 1. 89 0.470
0.047 32 12/04/75 4:00 0.068 5.41 28 1. 82 0.450
0.036 48 8/26/77 7:00 0.059 5.38 29 1. 75 0.430
0.099 19 12/15/77 18:00 0.048 5.30 30 1. 70 0.410
0.035 49 2/12/79 18:00 0.048 5.18 31 1. 64 0.390
0 .171 7 12/17/79 20:00 0.047 5 .11 32 1. 5 9 0.370
0.059 29 12/30/80 22:00 0.047 5.08 33 1. 54 0.350
0.138 10 10/06/81 18:00 0.047 5.02 34 1. 4 9 0.330
0.068 28 1/08/83 3:00 0.046 4.87 35 1. 45 0.310
0.039 45 12/10/83 19:00 0.044 4. 59 36 1. 41 0. 291
0.041 41 11/04/84 8:00 0.044 4. 48 37 1. 37 0 .271
0.104 16 1/19/86 0:00 0.044 4.42 38 1. 33 0.251
0.168 8 11/24/86 8:00 0.044 4.37 39 1. 30 0.231
0.044 40 12/10/87 8:00 0.044 4.37 40 1. 27 0. 211
0.040 42 11/05/88 22:00 0.041 3.93 41 1. 24 0.191
0.208 3 1/09/90 12:00 0.040 3.79 42 1. 21 0.171
0.189 4 11/24/90 16:00 0.040 3.77 43 1. 18 0.151
0.090 21 1/31/92 6:00 0.039 3.59 44 1.15 0.131
0.038 47 1/26/93 4:00 0.039 3.58 45 1.12 0.111
0.034 50 2/17/94 22:00 0.039 3.57 46 1.10 0.091
0.116 13 12/27/94 7:00 0.038 3.38 47 1.08 0.071
0.227 2 2/09/96 3:00 0.036 3.09 48 1. 05 0.051
0 .163 9 1/02/97 12:00 0.035 2.97 49 1. 03 0.031
0.040 43 1/25/98 0:00 0.034 2.77 50 1.01 0. 011
Computed Peaks 0.366 8.54 100.00 0.990
Computed Peaks 0. 296 8.52 50.00 0.980
Computed Peaks 0.235 8.42 25.00 0. 960
Computed Peaks 0.168 7.36 10.00 0.900
Computed Peaks 0 .156 7.28 8.00 0.875
Computed Peaks 0.124 6.64 5.00 0.800
Computed Peaks 0.073 5.47 2.00 0.500
Computed Peaks 0.048 5.21 1. 30 0.231
Flow Frequency Analysis LogPearson III Coefficients
Time Series File:dsout.tsf Mean= -1.037 StdDev~ 0.206
Project Location:Sea-Tac Skew~ 0. 672
---Annual Peak Flow Rates--------Flow Frequency Analysis-------
Flow Rate Rank Time of Peak --Peaks Rank Return Prob
(CFS) (CFS) Period
0.066 35 2/16/49 21:00 0.291 1 89.50 0.989
0.104 19 3/05/50 4:00 0.238 2 32.13 0. 969
0. 291 1 2/09/51 20:00 0.218 3 19.58 0.949
0.054 45 1/30/52 8:00 0.196 4 14.08 0.929
0. 096 21 1/18/53 19:00 0.193 5 10.99 0.909
o. 062 39 12/19/53 19:00 0.183 6 9.01 0.889
0.069 31 11/25/54 2:00 0.178 7 7.64 0.869
0.133 11 1/06/56 9:00 0.173 8 6.63 0.849
0.070 30 12/09/56 14:00 0.167 9 5.86 0. 829
0.087 24 1/17/58 6:00 0.164 10 5.24 0.809
0. 065 36 1/26/59 20:00 0.133 11 4.75 0.789
0.193 5 11/21/59 1:00 0.129 12 4.34 0.769
0.126 13 11/24/60 8:00 0.126 13 3.99 0.749
0.054 46 12/22/61 17:00 0.123 14 3.70 0.729
0.074 27 11/30/62 17:00 0.122 15 3.44 0.709
0.106 17 11/19/63 15:00 0.111 16 3.22 0.690
0.122 15 12/01/64 6:00 0.106 17 3.03 0.670
0.069 33 1/05/66 16:00 0.105 18 2.85 0.650
0.099 20 12/13/66 10:00 0.104 19 2.70 0.630
0.069 34 8/24/68 16:00 0.099 20 2.56 0.610
0.060 40 12/03/68 16:00 0. 096 21 2.44 0.590
0.091 23 1/27 /70 1:00 0.095 22 2.32 0.570
0.072 28 12/07 /70 10:00 0.091 23 2.22 0.550
0.183 6 3/06/72 21:00 0.087 24 2.13 0.530
0.129 12 12/26/72 3:00 0.076 25 2.04 0.510
0.076 25 1/18/74 16:00 0.074 26 1. 96 0.490
0.074 26 12/26/74 23:00 0.074 27 1. 89 0.470
0.060 41 12/02/75 20:00 0.072 28 1. 82 0.450
0.065 37 8/26/77 2:00 0.071 29 1. 75 0. 430
0.105 18 12/15/77 16:00 0.070 30 1. 70 0.410
0.051 48 9/08/79 15:00 0.069 31 1. 64 0.390
0.178 7 12/17/79 19:00 0.069 32 1. 59 0.370
0.069 32 11/21/80 11: 00 0.069 33 1. 54 0.350
0 .164 10 10/06/81 15:00 0.069 34 1. 49 0.330
0.071 29 1/08/83 2:00 0.066 35 1. 45 0.310
0.057 44 1/03/84 1:00 0.065 36 1. 41 0.291
0.054 47 11/03/84 11: 00 0.065 37 1. 37 0.271
0 .111 16 1/18/86 21:00 0.065 38 1. 33 0.251
0.173 8 11/24/86 7:00 0.062 39 1. 30 0.231
0.059 43 12/09/87 16:00 0.060 40 1. 27 0 .211
0.060 42 11/05/88 14:00 0.060 41 1. 24 0.191
0.218 3 1/09/90 10:00 0.060 42 1. 21 0.171
0 .196 4 11/24/90 15:00 0.059 43 1.18 0.151
0.095 22 1/31/92 5:00 0.057 44 1.15 0 .131
0.048 49 3/22/93 22:00 0.054 45 1.12 0.111
0.048 50 2/17/94 18:00 0.054 46 1.10 0.091
0.123 14 12/27/94 5:00 0.054 47 1. 08 0.071
0.238 2 2/09/96 2:00 0.051 48 1. 05 0.051
0.167 9 1/02/97 12:00 0.048 49 1. 03 0.031
0.065 38 10/04/97 15:00 0.048 50 1. 01 0. 011
Computed Peaks 0.347 100.00 0.990
Computed Peaks 0.285 50.00 0.980
Computed Peaks 0.232 25.00 0. 960
Computed Peaks 0.172 10.00 0.900
Computed Peaks 0.162 8.00 0.875
Computed Peaks 0.134 5.00 0. 800
Computed Peaks 0.087 2.00 0.500
Computed Peaks 0.063 1. 30 0.231
Flow Duration from Time Series File:rdout.tsf
Cutoff Count Frequency CDF Exceedence Probability
CFS % s
0.004 210961 48.165 48.165 51.835 0.518E+OO
0.012 69673 15.907 64.072 35.928 0.359E+OO
0.020 56387 12.874 76.945 23.055 0.231E+00
0.028 46826 10.691 87.636 12.364 0.124E+OO
0.036 31418 7.173 94.809 5.191 0.519E-01
0.044 16092 3.674 98.483 1.517 0.152E-01
0.052 4543 1.037 99.521 0.479 0.479E-02
0.060 161 0.037 99.557 0.443 0.443E-02
0. 068 140 0.032 99.589 0. 411 0.411E-02
0.076 308 0.070 99.660 0.340 0.340E-02
0.084 243 0.055 99.715 0.285 0.285E-02
0.092 242 0.055 99.770 0.230 0.230E-02
0.100 238 0.054 99.825 0.175 0.175E-02
0.108 170 0.039 99.863 0.137 0.137E-02
0.116 173 0.039 99.903 0.097 0.970E-03
0.124 124 0.028 99.931 0.069 0.687E-03
0.132 92 0.021 99.952 0.048 0.477E-03
0.140 81 0.018 99.971 0.029 0.292E-03
0.148 15 0.003 99.974 0. 026 0.258E-03
0.156 5 0.001 99.975 0.025 0.247E-03
0. 164 12 0.003 99.978 0.022 0.219E-03
0.172 23 0.005 99.983 0.017 0.167E-03
0.180 16 0.004 99.987 0.013 0.130E-03
0.188 13 0.003 99.990 0. 010 O.lOOE-03
0.196 8 0.002 99.992 0.008 0.822E-04
0.204 8 0.002 99.994 0.006 0.639E-04
0.212 11 0.003 99. 996 0.004 0.388E-04
0.220 3 0.001 99.997 0.003 0.320E-04
0.228 8 0.002 99.999 0.001 0.137E-04
0.236 3 0.001 99.999 0.001 0.685E-05
0.244 1 0.000 100.000 0.000 0.457E-05
0.252 1 0.000 100.000 0.000 0.228E-05
0.260 0 0.000 100.000 0.000 0.228E-05
0.268 0 0.000 100.000 0.000 0.228E-05
0.276 0 0.000 100.000 0.000 0.228E-05
0.284 0 0.000 100.000 0.000 0.228E-05
Flow Duration from Time Series File:dsout.tsf
Cutoff Count Frequency CDF Exceedence Probability
CFS % %
0.004 210159 47.982 47.982 52.018 0.520E+00
0.012 68803 15.708 63.690 3 6. 310 0.363E+OO
0.020 55487 12.668 76.358 23.642 0.236E+00
0. 029 46466 10.609 86. 967 13.033 0.130E+OO
0.037 31587 7 .212 94. 17 9 5.821 0.582E-01
0.045 16813 3.839 98.017 1.983 0.198E-01
0.053 5729 1. 308 99.325 0.675 0.675E-02
0.061 818 0.187 99.512 0. 488 0.488E-02
0.069 290 0.066 99.578 0. 422 0.422E-02
0.078 306 0.070 99.648 0.352 0.352E-02
0.086 265 0. 061 99.708 0. 292 0.292E-02
0.094 241 0.055 99. 763 0.237 0.237E-02
0.102 231 0.053 99.816 0.184 0.184E-02
0 .110 180 0.041 99.857 0.143 0.143E-02
0 .118 164 0.037 99.895 0.105 0.105E-02
0.127 130 0.030 99.924 0.076 0.756E-03
0.135 104 0.024 99.948 0.052 0.518E-03
0.143 62 0.014 99. 962 0.038 0.377E-03
0.151 34 0.008 99.970 0.030 0.299E-03
0 .159 17 0.004 99.974 0.026 0.260E-03
0.167 14 0.003 99.977 0.023 0.228E-03
0.176 24 0.005 99.983 0.017 0.174E-03
0.184 15 0.003 99.986 0.014 0.139E-03
0.192 11 0.003 99.989 0.011 0 .114E-03
0.200 11 0.003 99.991 0.009 0.890E-04
0.208 10 0.002 99.993 0.007 0.662E-04
0.216 8 0.002 99.995 0.005 0.479E-04
0.225 6 0.001 99.997 0.003 0.342E-04
0.233 4 0.001 99.997 0.003 0.251E-04
0.241 6 0.001 99.999 0.001 0 .114E-04
0.249 2 0.000 99.999 0.001 0.685E-05
0.257 1 0.000 100.000 0.000 0.457E-05
0.265 1 0.000 100.000 0.000 0.228E-05
0.273 0 0.000 100.000 0.000 0.228E-05
0.282 0 0.000 100.000 0.000 0.228E-05
0.290 0 0.000 100.000 0.000 0.228E-05
Duration Comparison Anaylsis
Base File: predevft.tsf
New File: dsout.tsf
Cutoff Units: Discharge in CFS
-----Fraction of Time--------------Check of Tolerance-------
Cutoff Base New %Change Probability Base New %Change
0.053 0.77E-02 0.66E-02 -14.6 I 0.77E-02 0.053 0.051 -4.2
0.071 0.40E-02 0.41E-02 2.3 I 0.40E-02 0.071 0.072 1.2
0.088 0.22E-02 0.27E-02 24.0 0.22E-02 0.088 0. 096 9.0
0.106 0.13E-02 0.16E-02 27.2 0.13E-02 0.106 0 .113 7.0
0.123 0.77E-03 0.87E-03 12.7 0. 77E-03 0.123 0.126 2.1
0.141 0.49E-03 0.39E-03 -20.0 0.49E-03 0.141 0 .136 -3.6
0.158 0.32E-03 0.26E-03 -18.6 0.32E-03 0.158 0.148 -6.6
0 .176 0.21E-03 0.17E-03 -21. 3 0.21E-03 0 .176 0.169 -3.7
0.193 0.12E-03 0.llE-03 -11. 5 0.12E-03 0.193 0.190 -1. 8
0 .211 0.64E-04 0.64E-04 0.0 0.64E-04 o. 211 0 .211 0.3
0.228 0.37E-04 0.30E-04 -18.8 0.37E-04 0.228 0.222 -2.8
0.246 0.14E-04 0.68E-05 -50.0 0.14E-04 0.246 0.237 -3.3
0 .263 0.46E-05 0.23E-05 -50.0 0.46E-05 0.263 0.260 -1. 0
0.280 0.23E-05 0.23E-05 0.0 0.23E-05 0.280 0.290 3.5
Maximum positive excursion = 0.008 cfs I 9.2%)
occurring at 0.085 cfs on the Base Data:predevft.tsf
and at 0.093 cfs on the New Data:dsout.tsf
Maximum negative excursion = 0.005 cfs I -7.8%)
occurring at 0.061 cfs on the Base Data:predevft.tsf
and at 0.056 cfs on the New Data:dsout.tsf
/()-_., . . ·
g 8 " "' ---0-'c:~o---t"""'c:-·o ___ o"""'c:--o---g""'r--o---c:""'r_o ___ a+o_-o---t0+.-o--oo-·+-o ~
5. CONVEYANCE SYSTEM ANALYSIS AND DESIGN
The stormwater drainage conveyance system will be sized to convey the 25 year design
storm event and to contain the 100 year design storm event. A detailed Conveyance
System Analysis and Design will be provided with the final TIR.
31
6. SPECIAL REPORTS AND STUDIES
Following are the reports and studies referenced for the proposed development
Geotechnical Engineering Report, by The Riley Group, Inc., dated July 08, 2015
32
••• l~-
RILEYGROUP
GEOTECHNICAL ENGINEERING REPORT
PREPARED BY:
THE RILEY GROUP, INC.
17522 BOTHELL WAY NORTHEAST
BOTHELL, WASHINGTON 98011
PREPARED FOR:
NORDIC RIDGE, LLC
15 LAKE BELLEVUE DRIVE, SUITE 102
BELLEVUE, WASHINGTON 98005
RGI PROJECT No. 2015-097
NORDIC RIDGE PLAT
17709 116TH AVENUE SOUTHEAST
RENTON, WASHINGTON
JULYS, 2015
Corporate Office
17522 Bothell Way Northea5t
Bothell, Washington 98011
Phone 425.415.0551 + Fax 425.415.0311
www.riley-group.com
July 8, 2015
Mr. Kevin O'Brien
Nordic Ridge, LLC
15 Lake Bellevue Drive, Suite 102
Bellevue, Washington 98005
••• ll.
RILEYGROUP
Subject: Geotechnical Engineering Report
Nordic Ridge Plat {Wells Property)
17709 116th Avenue Southeast
Renton, Washington
RGI Project No. 201S-097
Dear Mr. O'Brien:
As requested, The Riley Group, Inc. (RGI) has performed a Geotechnical Engineering
Report {GER) for the Nordic Ridge Plat located at 17709 116th Avenue Southeast, Renton,
Washington. Our services were completed in accordance with our proposal PRP201S-157
dated June 15, 2015 and authorized by Mr. Jeffrey Hamilton the CFO for Nordic Ridge, LLC
on June 16, 2015. The information in this GER is based on our understanding of the
proposed construction, and the soil and groundwater conditions encountered in the test
pits completed by RGI at the site on July 1, 2015.
RGI recommends that you submit the project plans and specifications to RGI for a general
review so that we may confirm that the recommendations in this GER are interpreted and
implemented properly in the construction documents. RGI also recommends that a
representative of our firm be present on site during portions of the project construction
to confirm that the soil and groundwater conditions are consistent with those that form
the basis for the engineering recommendations in this GER.
If you have any questions or require additional information, please contact us.
Respectfully submitted,
ERIC L _WOODS
Eric L. Woods, LG
Project Geologist
Tacoma, Washington
Phone 253.565.0552
Kristina M. Weller, PE
Senior Project Engineer
Corporate Office
17522 Bothell Way Northeast
Bothe/J, Washington 98011
Phone425.415.0551 + Fax425.415.0311
www.riley-group.com
Kennewick, Washington
Phone 509.586.4840
Geotechnical Engineering Report
Nordic Ridge Plat, Renton, Washington
July 8, 2015
RGI Project No. 2015-097
TABLE OF CONTENTS
1.0 INTRODUCTION .. , .. , ... , ..... , ............................................................................................................... I
2.0 PROJECT DESCRIPTION ............................................................................................................... 1
3.0 FIELD EXPLORATION AND LABORATORY TESTING .......................................................... 1
4.0
5.0
3.1 FIELD EXPLORATION ................................................................................................................................... 1
3.2 LABORATORY TESTING ................................................................................................................................ 2
SITE CONDITIONS ........................................................................................................................... 2
4.1 SURFACE ..................................................................................................... . . ............................. 2
4.2 GEOLOGY ................................................................................................................................................ 2
4.3 SOIL.S ...................................................................................................................................................... 2
4.4 GROUNDWATER ....................................................................................................................................... 3
4.5 SEISMIC CONSIDERATIONS.......... . ....................................................................................................... 3
4.6 GEOLOGIC HAZARD AREAS ......................................................................... 4
DISCUSSION AND RECOMMENDATIONS ................................................................................. 4
5.1 GEOTECHNICAL CONSIDERATIONS................................. ......................................... . ............... 4
5.2 EARTHWORK ............................................................................................................................................ 4
5.2.1 Erosion and Sediment Control .................................................................................................... 4
5.2.2 Stripping ....................................................................................................................................... 5
5.2.3 Excavations.. . ........................................................................................................ 6
5.2.4 Site Preparation ..
5.2.5 Structural Fill
5.2.6 Cut and Fill Slopes ..
5.2.7 Wet Weather Construction Considerations
5.3 FOUNDATIONS ...... .
5.4 RETAINING WALLS ..
5.4.1 Cast-In-Place Walls.
5.5 SLAB-ON-GRADE CONSTRUCTION
5.6 DRAINAGE .................... .
5.6.1 Surface.
S.6.2 Subsurface ...................................................... .
S.6.3 Infiltration ........................................................ .
5.7 UTILITIES .........................................................•........
5.8 PAVEMENTS ............................................................ .
. ........................................................ 6
.............................................................. 7
. ............................................................... 9
........................ 9
. ........................................... 9
. ........... 10
.. ............ 10
.......... 11
. ........................................... 11
. ....... 11
. .... 12
. ......... 12
. ............ 12
. ........ 12
6.0 ADDITIONAL SERVICES .............................................................................................................. 13
7.0 LIMITATIONS ................................................................................................................................. 13
LIST OF FIGURES AND APPENDICES
Figure 1 ..................................................................................................................... Site Vicinity Map
Figure 2 ................................................................................................ Geotechnicol Exploration Plan
Figure 3 .................................................................................. Typical Retaining Wall Drainage Detail
Figure 4 ................................................................................................... Typical Footing Drain Detail
Appendix A .......................................................................... Field Exploration and Laboratory Testing
Geotechnical Engineering Report
Nordic Ridge Plat Renton, Washington
Executive Summary
July 8, 2015
RGI Project No. 2015-097
This Executive Summary should be used in conjunction with the entire Geotechnical
Engineering Report (GER) for design and/or construction purposes. It should be
recognized that specific details were not included or fully developed in this section, and
the GER must be read in its entirety for a comprehensive understanding of the items
contained herein. Section 7.0 should be read for an understanding of limitations.
RGl's geotechnical scope of work included the advancement of eight test pits to
approximate depths of six to eight feet below existing site grades.
Based on the information obtained from our subsurface exploration, the site is suitable
for development of the proposed project. The following geotechnical considerations were
identified:
Soil Conditions: The soils encountered during field exploration include loose to very
dense silty sand with gravel.
Groundwater: No groundwater seepage was encountered during our subsurface
exploration. However, iron oxide staining was observed at 3 to 4 feet indicating a perched
seasonal groundwater table over the top of dense glacial till layer.
Foundations: Foundations for the proposed building may be supported on conventional
spread footings bearing on medium dense to dense native soil or structural fill
Slab-on-grade: Slab-on-grade floors and slabs for the proposed building can be supported
on medium dense to dense native soil or structural fill.
Pavements: The following pavement sections are recommended in accordance with the
preferred section in the King County Road Design and Construction Standards -2007:
}-For Residential Streets: 2 inches of Class Y, inch Hot Mix Asphalt (HMA) over 4
inches of Class% or 1 inch HMA
••• ll-nu cvrinn11n,,
Geotechnical Engineering Report
Nordic Ridge Plat, Renton, Washington
1.0 Introduction
July 8, 2015
RGI Project No. 2015-097
This Geotechnical Engineering Report (GER) presents the results of the geotechnical
engineering services provided for the Nordic Ridge Plat in Renton, King County,
Washington. The purpose of this evaluation is to assess subsurface conditions and
provide geotechnical recommendations for the construction of a residential plat. Our
scope of services included field explorations, laboratory testing, engineering analyses, and
preparation of this GER.
The recommendations in the following sections of this GER are based upon our current
understanding of the proposed site development as outlined below. If actual features
vary or changes are made, RGI should review them in order to modify our
recommendations as required. In addition, RGI requests to review the site grading plan,
final design drawings and specifications when available to verify that our project
understanding is correct and that our recommendations have been properly interpreted
and incorporated into the project design and construction.
2.0 Project description
The project site is located at 17709 116th Avenue Southeast in Renton, Washington. The
approximate location of the site is shown on Figure 1.
The site is currently occupied by a single family residence with outbuildings and pasture
areas. We understand it is proposed to construct a residential development on the site
with access roadways, underground utilities and storm water facilities.
At the time of preparing this GER, building plans were not available for our review. Based
on our experience with similar construction, RGI anticipates that the proposed residences
will be supported on perimeter walls with bearing loads of two to four kips per linear
foot, and a series of columns with a maximum load up to 70 kips. Slab-on-grade floor
loading of 250 pounds per square foot (psf) are expected.
3.0 Field Exploration and Laboratory Testing
3.1 FIELD EXPLORATION
On July 1, 2015, RGI observed the excavation of eight test pits. The approximate
exploration locations are shown on Figure 2.
Field logs of each exploration were prepared by the geologist that continuously observed
the excavation. These logs included visual classifications of the materials encountered
during drilling as well as our interpretation of the subsurface conditions between
samples. The test pits logs included in Appendix A represent an interpretation of the field
••• I~-
R1LEYGRouP
Geotechnicaf Engineering Report
Nordic Ridge Plat, Renton, Wa5hington
July 8~ 2015
RGI Project No. 2015-097
logs and include modifications based on laboratory observation and analysis of the
samples.
3.2 LABORATORY TESTING
During the field exploration, a representative portion of each recovered sample was
sealed in containers and transported to our laboratory for further visual and laboratory
examination. Selected samples retrieved from the test pits were tested for moisture
content and grain size analysis to aid in soil classification and provide input for the
recommendations provided in this GER. The results and descriptions of the laboratory
tests are enclosed in Appendix A.
4.0 Site Conditions
4.1 SURFACE
The subject site is an irregular-shaped parcel of land approximately 3.63 acres in size. The
site is bound to the north by Southeast Petrovitsky Road and residential property, to the
east by 116th Avenue Southeast and residential property, to the south by residential
property, and to the west by Southeast 177th Place and residential property.
The site contains a single-family residence and several out-buildings in the central portion
of the property, with the remainder of the site vegetated by grass. Several medium-
diameter trees are located around the residence and in the southern portion of the
property. Small-diameter trees ring a fenced off pasture in the northern portion of the
site. The site slopes generally northeast at gradients of about 10 percent with an
elevation change across the site of approximately 30 feet.
4.2 GEOLOGY
Review of the Geologic Map of the Renton Quadrangle, King County, Washington, by D. R.
Mullineaux (1965) indicates that the soil in the project vicinity is mapped as Ground
moraine deposits (Qgt}, which is light to dark gray, nonsorted, nonstratified mixture of
clay, silt, sand, and gravel deposited by glacial ice. The deposit is generally very stiff and
impermeable, often resulting in poorly drained bogs developing in relatively flat area. The
deposit is usually 1 to 2 meters thick, but locally can be as much as 25 meters. These
descriptions are generally similar to the findings in our field explorations.
4.3 SOILS
The soils encountered during field exploration include loose to very dense silty sand with
gravel. The soil generally becomes denser with depth .
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Geotechnical Engineering Report
Nordic Ridge Plat, Renton, Washington
July 8, 2015
RGI Project No. 2015-097
More detailed descriptions of the subsurface conditions encountered are presented in
the test pits included in Appendix A. Sieve analysis was performed on three selected soil
samples. Grain size distribution curves are included in Appendix A.
4.4 GROUNDWATER
No groundwater seepage was encountered during our subsurface exploration. However,
iron oxide staining was observed at 3 to 4 feet indicating a perched seasonal groundwater
table over the top of dense glacial till layer.
It should be recognized that fluctuations of the groundwater table will occur due to
seasonal variations in the amount of rainfall, runoff, and other factors not evident at the
time the explorations were performed. In addition, perched water can develop within
seams and layers contained in fill soils or higher permeability soils overlying less
permeable soils following periods of heavy or prolonged precipitation. Therefore,
groundwater levels during construction or at other times in the future may be higher or
lower than the levels indicated on the logs. Groundwater level fluctuations should be
considered when developing the design and construction plans for the project.
4.5 SEISMIC CONSIDERATIONS
Based on the 2012 International Building Code (IBC), RGI recommends the follow seismic
parameters for design.
Site Soil Class 1
Site Latitude
Site Longitude
Table 1 2012 IBC
Parameter
Short Period Spectral Response Acceleration, Ss (g)
1-Second Period Spectral Response Acceleration, S, (g)
Adjusted Short Period Spectral Response Acceleration, SMs (g)
Adjusted 1-Second Period Spectral Response Acceleration, SM1 (g)
i
-~-
I
Value
C'
47.44399° N
122.18701° W
1.386
0.517
1.386
0.672
1. Note: In general accordance with Chapter 20 of ASCE 7. Th~-Site ciaSs is-based on the average characteristics of the upper 100 feet
of the subsurface profile.
2. Note: The 2012 IBC and ASCE 7 require a site soil profile determination extending to a depth of 100 feet for seismic site
classification. The current scope of our services does not include the required 100 foot soil profile determination. Test pits extended to
a maximum depth of 8 feet, and this seismic site class definition considers that very dense soil continues below the maximum depth of
the subsurface exploration. Additional exploration to deeper depths would be required to confirm the conditions below the current
depth of exploration.
• •• ·~-RILEYGROUP
Geotechnicol Engineering Report
• Nordic Ridge Plat, Renton, Washington
4 July 8, 2D15
RGI Project No. 2015-097
Liquefaction is a phenomenon where there is a reduction or complete loss of soil strength
due to an increase in water pressure induced by vibrations from a seismic event.
Liquefaction mainly affects geologically recent deposits of fine-grained sands that are
below the groundwater table. Soils of this nature derive their strength from intergranular
friction. The generated water pressure or pore pressure essentially separates the soil
grains and eliminates this intergranular friction, thus reducing or eliminating the soil's
strength.
RGI reviewed the results of the field and laboratory testing and assessed the potential for
liquefaction of the site's soil during an earthquake. Since the site is underlain by glacial
till, RGI considers that the possibility of liquefaction during an earthquake is minimal.
4.6 GEOLOGIC HAZARD AREAS
Regulated geologically hazardous areas include erosion, landslide, earthquake, or other
geological hazards. Based on the definition in the King County Code, the site does not
contain geologically hazardous areas.
5.0 Discussion and Recommendations
5.1 GEOTECHNICAL CONSIDERATIONS
Based on our study, the site is suitable for the proposed construction from a geotechnical
standpoint. Foundations for the proposed building can be supported on conventional
spread footings bearing on medium dense to dense native soil or structural fill. Slab-on-
grade and pavements can be similarly supported.
Detailed recommendations regarding the above issues and other geotechnical design
considerations are provided in the following sections. These recommendations should be
incorporated into the final design drawings and construction specifications.
5.2 EARTHWORK
The earthwork for the project is expected to include mass grading to achieve lot and
roadway grades, excavating the detention pond, installing underground utilities and
preparing roadway subgrades.
5.2.1 EROSION AND SEDIMENT CONTROL
Potential sources or causes of erosion and sedimentation depend on construction
methods, slope length and gradient, amount of soil exposed and/or disturbed, soil type,
construction sequencing and weather. The impacts on erosion-prone areas can be
reduced by implementing an erosion and sedimentation control plan. The plan should be
designed in accordance with applicable city and/or county standards .
••• ·~-RILEYGROUf>
Geotechnicaf Engineering Report
• Nordic Ridge Plat, Renton, Washington
July 8, 2015
RGI Project No. 2015·097
RGI recommends the following erosion control Best Management Practices (BMPs):
r Scheduling site preparation and grading for the drier summer and early fall
months and undertaking activities that expose soil during periods of little or no
rainfall
r Retaining existing vegetation whenever feasible
r Establishing a quarry spall construction entrance
r Installing siltation control fencing or anchored straw or coir wattles on the
downhill side of work areas
r Covering soil stockpiles with anchored plastic sheeting
r Revegetating or mulching exposed soils with a minimum 3-inch thickness of straw
if surfaces will be left undisturbed for more than one day during wet weather or
one week in dry weather
r Directing runoff away from exposed soils and slopes
r Minimizing the length and steepness of slopes with exposed soils and cover
excavation surfaces with anchored plastic sheeting (Graded and disturbed slopes
should be tracked in place with the equipment running perpendicular to the slope
contours so that the track marks provide a texture to help resist erosion and
channeling. Some sloughing and raveling of slopes with exposed or disturbed soil
should be expected.)
r Decreasing runoff velocities with check dams, straw bales or coir wattles
r Confining sediment to the project site
)"" Inspecting and maintaining erosion and sediment control measures frequently
(The contractor should be aware that inspection and maintenance of erosion
control BMPs is critical toward their satisfactory performance. Repair and/or
replacement of dysfunctional erosion control elements should be anticipated.)
Permanent erosion protection should be provided by reestablishing vegetation using
hydroseeding and/or landscape planting. Until the permanent erosion protection is
established, site monitoring should be performed by qualified personnel to evaluate the
effectiveness of the erosion control measures. Provisions for modifications to the erosion
control system based on monitoring observations should be included in the erosion and
sedimentation control plan.
5.2.2 STRIPPING
Stripping efforts should include removal of pavements, vegetation, organic materials, and
deleterious debris from areas slated for building, pavement, and utility construction. The
test pits encountered six to eight inches of topsoil and rootmass. Deeper areas of
stripping may be required in forested or heavily vegetated areas of the site .
••• ·~-RILEYGROUP
Geotechnical Engineering Report
Nordic Ridge Plat, Renton, Washington
5.2.3 EXCAVATIONS
July 8, 2015
RGI Project No. 2015-097
All temporary cut slopes associated with the site and utility excavations should be
adequately inclined to prevent sloughing and collapse. The site soils consist of medium
dense to very dense silty sand with gravel.
Accordingly, for excavations more than 4 feet but less than 20 feet in depth, the
temporary side slopes should be laid back with a minimum slope inclination of lH:lV
(Horizontal:Vertical). The slope inclination may be increased to 3/4H:1V in the very dense
till. If there is insufficient room to complete the excavations in this manner, or
excavations greater than 20 feet in depth are planned, using temporary shoring to
support the excavations should be considered. For open cuts at the site, RGI
recommends:
> No traffic, construction equipment, stockpiles or building supplies are allowed at
the top of cut slopes within a distance of at least five feet from the top of the cut
> Exposed soil along the slope is protected from surface erosion using waterproof
tarps and/or plastic sheeting
> Construction activities are scheduled so that the length of time the temporary cut
is left open is minimized
> Surface water is diverted away from the excavation
> The general condition of slopes should be observed periodically by a geotechnical
engineer to confirm adequate stability and erosion control measures
In all cases, however, appropriate inclinations will depend on the actual soil and
groundwater conditions encountered during earthwork. Ultimately, the site contractor
must be responsible for maintaining safe excavation slopes that comply with applicable
OSHA or WISHA guidelines.
5.2.4 SITE PREPARATION
RGI anticipates that some areas of loose or soft soil will be exposed upon completion of
stripping and grubbing. Proofrolling and subgrade verification should be considered an
essential step in site preparation. After stripping, grubbing, and prior to placement of
structural fill, RGI recommends proofrolling building and pavement subgrades and areas
to receive structural fill. These areas should moisture condition and compacted to a firm
and unyielding condition in order to achieve a minimum compaction level of 95 percent
of the modified proctor maximum dry density as determined by the American Society of
Testing and Materials 01557-09 Standard Test Methods for Laboratory Compaction
Characteristics of Soil Using Modified Effort (ASTM D1557).
Proofrolling and adequate subgrade compaction can only be achieved when the soils are
within approximately ± 2 percent moisture content of the optimum moisture content.
Soils which appear firm after stripping and grubbing may be proofrolled with a heavy
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Geotechnicol Engineering Report
Nordic Ridge Plat, Renton, Washington
July 8, 2015
RGI Project No. 2015-097
compactor, loaded double-axle dump truck, or other heavy equipment under the
observation of an RGI representative. This observer will assess the subgrade conditions
prior to filling. The need for or advisability of proofrolling due to soil moisture conditions
should be determined at the time of construction. In wet areas it may be necessary to
hand probe the exposed subgrades in lieu of proofrolling with mechanical equipment.
Subgrade soils that become disturbed due to elevated moisture conditions should be
overexcavated to reveal firm, non-yielding, non-organic soils and backfilled with
compacted structural fill. In order to maximize utilization of site soils as structural fill, RGI
recommends that the earthwork portion of this project be completed during extended
periods of warm and dry weather if possible. If earthwork is completed during the wet
season (typically November through May) it will be necessary to take extra precautionary
measures to protect subgrade soils. Wet season earthwork will require additional
mitigative measures beyond that which would be expected during the drier summer and
fall months.
5.2.5 STRUCTURAL FILL
Once stripping, clearing and other preparing operations are complete, cuts and fills can
be made to establish desired lot and roadway grades. Prior to placing fill, RGI
recommends proof-rolling as described above. RGI recommends fill below the foundation
and floor slab, behind retaining walls, and below pavement and hardscape surfaces be
placed in accordance with the following recommendations for structural fill.
The suitability of excavated site soils and import soils for compacted structural fill use will
depend on the gradation and moisture content of the soil when it is placed. As the
amount of fines (that portion passing the U.S. No. 200 sieve) increases, soil becomes
increasingly sensitive to small changes in moisture content and adequate compaction
becomes more difficult or impossible to achieve. Soils containing more than about 5
percent fines cannot be consistently compacted to a dense, non-yielding condition when
the moisture content is more than 2 percent above or below optimum. Optimum
moisture content is that moisture that results in the greatest compacted dry density with
a specified compactive effort.
Non-organic site soils are only considered suitable for structural fill provided that their
moisture content is within about two percent of the optimum moisture level as
determined by ASTM D1557. Excavated site soils may not be suitable for re-use as
structural fill depending on the moisture content and weather conditions at the time of
construction. If soils are stockpiled for future reuse and wet weather is anticipated, the
stockpile should be protected with plastic sheeting that is securely anchored. Even during
dry weather, moisture conditioning (such as, windrowing and drying) of site soils to be
reused as structural fill may be required. Even during the summer, delays in grading can
occur due to excessively high moisture conditions of the soils or due to precipitation. If
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RILEYGROUP'
Geotechnicol Engineering Report
Nordic Ridge Pfat, Renton, Washington
July 8, 2015
RGI Project No. 2015-097
wet weather occurs, the upper wetted portion of the site soils may need to be scarified
and allowed to dry prior to further earthwork, or may need to be wasted from the site.
The site soils are moisture sensitive and will not be useable for will in wet weather. If
grading operations take place in the summer and fall months, it should be feasible to
moisture condition and compact the native soil. If on-site soils are or become unusable, it
may become necessary to import clean, granular soils to complete site work that meet
the grading requirements listed in Table 2 to be used as structural fill.
Table 2 Structural Fill Gradation
4 inches 100
I
No. 4 sieve j--75 percent
------------
5 percent*
----
No. 200 sieve
•Ba~d on minus 3/4 inch fraction.
Prior to use, an RGI representative should observe and test all materials imported to the
site for use as structural fill. Structural fill materials should be placed in uniform loose
layers not exceeding 12 inches and compacted as specified in Table 2. The soil's maximum
density and optimum moisture should be determined by ASTM D1557.
Table 3 Structural Fill Compaction ASTM 01557
Minimum Moisture Content . Location Material Type · ' Compahion ··· .. . Rarig,f.
Percentage
Foundations On-site granular or approved 95 +2 -2
--------imported fill S?ils: t----
On-site granular or approved I I
Retaining Wall Backfill imported fill soils: I
92
!
+2 -2
'
i On-site granular or approved 95 ' +2 -2 Slab-on-grade
------·-imported fill soils:
General Fill (non-On-site soils or approved 90 +3 -2
_st_r_u_ct_u_r_a_l _a_re_a_s~) __ --+_1_m_p_o_rt_e_d fill soils: JJ~ -I :: I
Pavement -Subgrade On-site gr:n~;ar or a;proved 95 ~2 ' _2 and Base Course imported fill soils:
---------
Placement and compaction of structural fill should be observed by RGI. A representative
number of in-place density tests should be performed as the fill is being placed to confirm
that the recommended level of compaction is achieved .
••• ·~-RILEYGROUP
Geotechnico/ Engineering Report
Nordic Ridge Plot, Renton, Washington
5.2.6 CUT AND FILL SLOPES
July 8, 2015
RGI Project No. 2015~097
All permanent cut and fill slopes (except interior slopes of detention pond) should be
graded with a finished inclination no greater than 2H:1V. The interior slopes of the
detention pond must be graded with a slope gradient no steeper than 3H:1V. Upon
completion of construction, the slope face should be trackwalked, compacted and
vegetated, or provided with other physical means to guard against erosion.
Final grades at the top of the slopes must promote surface drainage away from the slope
crest. Water must not be allowed to flow in an uncontrolled fashion over the slope face. If
it is necessary to direct surface runoff towards the slope, it should be controlled at the
top of the slope, piped in a closed conduit installed on the slope face, and taken to an
appropriate point of discharge beyond the toe of the slope. All fill placed for slope
construction should meet the structural fill requirements as described in Section 5.2.5.
5.2. 7 WET WEATHER CONSTRUCTION CONSIDERATIONS
RGI recommends that preparation for site grading and construction include procedures
intended to drain ponded water, control surface water runoff, and to collect shallow
subsurface seepage zones in excavations where encountered. It will not be possible to
successfully compact the subgrade or utilize on-site soils as structural fill if accumulated
water is not drained prior to grading or if drainage is not controlled during construction.
Attempting to grade the site without adequate drainage control measures will reduce the
amount of on-site soil effectively available for use, increase the amount of select import
fill materials required, and ultimately increase the cost of the earthwork phases of the
project. Free water should not be allowed to pond on the subgrade soils. RGI anticipates
that the use of berms and shallow drainage ditches, with sumps and pumps in utility
trenches, will be required for surface water control during wet weather and/or wet site
conditions.
5.3 FOUNDATIONS
Following site preparation and grading, the proposed building foundation can be
supported on conventional spread footings bearing on dense native soil or structural fill.
Loose, organic, or other unsuitable soils may be encountered in the proposed building
footprint. If unsuitable soils are encountered, they should be overexcavated and
backfilled with structural fill.
Perimeter foundations exposed to weather should be at a minimum depth of 18 inches
below final exterior grades. Interior foundations can be constructed at any convenient
depth below the floor slab. Finished grade is defined as the lowest adjacent grade within
5 feet of the foundation for perimeter (or exterior) footings and finished floor level for
interior footings.
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Geotechnico/ Engineering Report
Nordic Ridge Plot, Renton, Washington
10
Table 4 Foundation Design
Allowable Bearing Capacity-Structural Fill
Friction Coefficient
Passive pressure (equivalent fluid pressure) !
Minimum foundation dimensions ,
1. psf = pounds per square foot
2. pd= pounds per cubic foot
July 8, 2015
RGI Project No. 2015-097
2,500 psf1
0.30
250 pcf2
-----------~---
Columns: 24 inches
Walls: 16 inches
The allowable foundation bearing pressures apply to dead loads plus design live load
conditions. For short-term loads, such as wind and seismic, a 1/3 increase in this
allowable capacity may be used. At perimeter locations, RGI recommends not including
the upper 12 inches of soil in the computation of passive pressures because they can be
affected by weather or disturbed by future grading activity. The passive pressure value
assumes the foundation will be constructed neat against competent soil or backfilled with
structural fill as described in Section 5.2.5. The recommended base friction and passive
resistance value includes a safety factor of about 1.5.
With spread footing foundations designed in accordance with the recommendations in
this section, maximum total and differential post-construction settlements of 1 inch and
1/2 inch, respectively, should be expected.
5.4 RETAINING WALLS
If retaining walls are needed for the future residences or within the detention pond, RGI
recommends cast-in-place concrete walls be used. If grade changes are necessary in lot or
landscape areas, modular block walls can be used. RGI can provide design for modular
block walls once the configuration and height of the walls has been determined.
5.4.1 CAST-IN-PLACE WALLS
The magnitude of earth pressure development on retaining walls will partly depend on
the quality of the wall backfill. RGI recommends placing and compacting wall backfill as
structural fill. Wall drainage will be needed behind the wall face. A typical retaining wall
drainage detail is shown in Figure 3. The perforated pipe shown in the detail may be
replaced with 2 inch diameter weep holes through the wall at 10 foot centers
approximately 6 inches above the wetpond or finished landscape surface for walls in the
detention pond or landscape areas .
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Geotechnicol Engineering Report
Nordic Ridge Plot, Renton, Washington
11 July 8, 2015
RGI Project No. 2015-097
With wall backfill placed and compacted as recommended, and drainage properly
installed, RGI recommends using the values in the following table for design.
Table 5 Retaining Wall Design
! Allowable Bearing Capacity -Structural Fill I
Active Earth Pressure (unrestrained walls)
At-rest Earth Pressure (restrained walls)
2,500 psf
35 pcf
50 pcf
For seismic design, an additional uniform load of 7 times the wall height (H} for
unrestrained walls and 14H for restrained walls should be applied to the wall surface.
Friction at the base of foundations and passive earth pressure will provide resistance to
these lateral loads. Values for these parameters are provided in Section 5.3.
5.5 SLAB-ON-GRADE CONSTRUCTION
Once site preparation has been completed as described in Section 5.2, suitable support
for slab-on-grade construction should be provided. RGI recommends that the concrete
slab be placed on top of medium dense native soil or structural fill. Immediately below
the floor slab, RGI recommends placing a four-inch thick capillary break layer of clean,
free-draining sand or gravel that has less than five percent passing the U.S. No. 200 sieve.
This material will reduce the potential for upward capillary movement of water through
the underlying soil and subsequent wetting of the floor slab. Where moisture by vapor
transmission is undesirable, an 8-to 10-millimeter thick plastic membrane should be
placed on a 4-inch thick layer of clean gravel.
For the anticipated floor slab loading, we estimate post-construction floor settlements of
1/4-to 1/2-inch.
5.6 DRAINAGE
5.6.1 SURFACE
Final exterior grades should promote free and positive drainage away from the building
area. Water must not be allowed to pond or collect adjacent to foundations or within the
immediate building area. For non-pavement locations, RGI recommends providing a
minimum drainage gradient of 3 percent for a minimum distance of 10 feet from the
building perimeter. In paved locations, a minimum gradient of 1 percent should be
provided unless provisions are included for collection and disposal of surface water
adjacent to the structure.
• •• . , ..
RILEYGROUP
Geotechnicaf Engineering Report
Nordic Ridge Plat, Renton, Washington
5.6.2 SUBSURFACE
12 July 8, 2015
RGI Project No. 2D15-D97
RGI recommends installing perimeter foundation drains. A typical footing drain detail is
shown on Figure 4. The foundation drains and roof downspouts should be tightlined
separately to an approved discharge facility. Subsurface drains must be laid with a
gradient sufficient to promote positive flow to a controlled point of approved discharge.
5.6.3 INFILTRATION
The site soils consist of weathered glacial till underlain by very dense unweather glacial
till. Iron oxide staining was observed at the interface of the unweathered till indicative of
a shallow seasonal perched groundwater table. Based on the soil conditions the site is not
suitable for infiltration.
5.7 UTILITIES
Utility pipes should be bedded and backfilled in accordance with American Public Works
Association (APWA) specifications. For site utilities located within the right-of-ways,
bedding and backfill should be completed in accordance with King County specifications.
At a minimum, trench backfill should be placed and compacted as structural fill, as
described in Section 5.2.5. Where utilities occur below unimproved areas, the degree of
compaction can be reduced to a minimum of 90 percent of the soil's maximum density as
determined by the referenced ASTM D1557.
As noted, soils excavated on site will not be suitable for use as backfill material in wet
weather. Imported structural fill meeting the gradation provided in Table 2 may be
necessary for trench backfill. The native soils should be suitable for use as backfill
material in the summer and fall months in dry weather, however moisture condition of
the soils should be expected.
5.8 PAVEMENTS
Pavement subgrades should be prepared as described in Section 5.2 and as discussed
below. Regardless of the relative compaction achieved, the subgrade must be firm and
relatively unyielding before paving. The subgrade should be proofrolled with heavy
construction equipment to verify this condition.
With the pavement subgrade prepared as described above, RGI recommends the
following pavement sections in accordance with the preferred section in the King County
Road Design and Construction Standards -2007:
~ For Residential Streets: 2 inches of Class Y, inch Hot Mix Asphalt (HMA) over 4
inches of Class% or 1 inch HMA
The asphalt paving materials used should conform to the Washington State Department
of Transportation (WSDOT) specifications for HMA surfacing .
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Geotechnica/ Engineering Report
Nordic Ridge Pfat, Renton, Washington
13 July 8, 2015
RGI Project No. 2015-097
Long-term pavement performance will depend on surface drainage. A poorly-drained
pavement section will be subject to premature failure as a result of surface water
infiltrating into the subgrade soils and reducing their supporting capability.
For optimum pavement performance, surface drainage gradients of no less than 2
percent are recommended. Also, some degree of longitudinal and transverse cracking of
the pavement surface should be expected over time. Regular maintenance should be
planned to seal cracks when they occur.
6.0 Additional Services
RGI is available to provide further geotechnical consultation throughout the design phase
of the project. RGI should review the final design and specifications in order to verify that
earthwork and foundation recommendations have been properly interpreted and
incorporated into project design and construction.
RGI is also available to provide geotechnical engineering and construction monitoring
services during construction. The integrity of the earthwork and construction depends on
proper site preparation and procedures. In addition, engineering decisions may arise in
the field in the event that variations in subsurface conditions become apparent.
Construction monitoring services are not part of this scope of work. If these services are
desired, please let us know and we will prepare a cost proposal.
7.0 Limitations
This GER is the property of RGI, Nordic Ridge, LLC, and its designated agents. Within the
limits of the scope and budget, this GER was prepared in accordance with generally
accepted geotechnical engineering practices in the area at the time this GER was issued.
This GER is intended for specific application to the Nordic Ridge Plat project in Renton,
Washington, and for the exclusive use of Nordic Ridge, LLC and its authorized
representatives. No other warranty, expressed or implied, is made. Site safety, excavation
support, and dewatering requirements are the responsibility of others.
The scope of services for this project does not include either specifically or by implication
any environmental or biological (for example, mold, fungi, bacteria) assessment of the
site or identification or prevention of pollutants, hazardous materials or conditions. If the
owner is concerned about the potential for such contamination or pollution, we can
provide a proposal for these services.
The analyses and recommendations presented in this GER are based upon data obtained
from the test exploration performed on site. Variations in soil conditions can occur, the
nature and extent of which may not become evident until construction. If variations
appear evident, RGI should be requested to reevaluate the recommendations in this GER
prior to proceeding with construction .
••• ·~-RILEYGROUP
Geotechnical Engineering Report
Nordic Ridge Plat, Renton, Washington
14 July 8, 2015
RGI Project No. 2015-097
It is the client's responsibility to see that all parties to the project, including the designers,
contractors, subcontractors, are made aware of this GER in its entirety. The use of
information contained in this GER for bidding purposes should be done at the contractor's
option and risk.
• •• ·~-RILEYGROUP
USGS, 1994, Renton, Washington
7.S-Minute Quadrangle
I I • Corporate Office
17522 Bothell Way Northeast I ~. Bothell, Washington 98011
RILEYGROUP Phone: 425.415.0551
Fax: 425.415.0311
Approximate Scale: 1"=1000'
0 500 1000
Nordic Ridge Plat (Wells Property)
RGI Project Number
2015-097
Site Vicinity Map
2000
Figure 1
Date Drawn:
07/2015
Address: 17709 116th Avenue Southeast, Renton, Washington 98058
,"------" ----'"""·-
.111!
TP-5
L
.111!
TP-6
.111!
TP-7
.111! = Test Pit Location by RGI on 07 /01/15
.111!
TP-4
··1a•
TP-8
!
.111!
TP-1
+
.1
i
Approximate Scale: 1"=100'
Drawn from ESM Consulting Engineers LLC, Preliminary Plat Plan PP-01. o 50 100
I I • Corporate Office
17522 Bothell Way Northeast I l .. Bothell, Washington 98011
Nordic Ridge Plat (Wells Property)
RGI Project Number
2015-097
Geotechnical Exploration Plan
A
200 N
Figure 2
Date Drawn:
07/2015
RILEYGROUP ::;":~;!~;~~i:si Address: 17709 116th Avenue Southeast, Renton, Washington 98058
12" Minimum Wide l e<-Orai,i,g:
Filter Fabric Material
I I • Corporate Office
17522 Bothell Way Northeast I l • Bothell, Washington 98011
RILEYGROUP ~=:t4·~;!~;~~i:si
Slope to Drain
Perforated Pipe
Not to Scale
Nordic Ridge Plat (Wells Property)
Excavated Slope
(See Report for
Appropriate
lncliniations)
Compacted Structural
Backfill (Native or Import)
Figure 3
RGI Project Number
2015-097
Retaining Wall Drainage Detail Date Drawn:
07/2015
Address: 17709 116th Avenue Southeast, Renton, Washington 98058
I I • Corporate Office
17522 Bothell Way Northeast I ~ • Bothell, Washington 98011
RILEYGROUP :::t:~;!~;~~J:51
...
..
Compacted
Structural
Backfill
4" Perforated Pipe
3/4" Washed Rock or Pea Gravel
Not to Scale
Nordic Ridge Plat (Wells Property)
Filter Fabric
RGI Project Number
2015-097
Typical Footing Drain Detail
Figure 4
Date Drawn:
07/2015
Address: 17709 116th Avenue Southeast, Renton, Washington 98058
Geotechnicaf Engineering Report
Nordic Ridge Plat, Renton, Wa5hington
APPENDIX A
July 8, 2015
RGI Project No. 2015-097
FIELD EXPLORATION AND LABORATORY TESTING
On July 1, 2015, RGI performed field explorations using a rubber tired backhoe. We
explored subsurface soil conditions at the site by observing the excavation of eight test
pits to a maximum depth of 8 feet below existing grade. The test pits locations are shown
on Figure 2. The test pits locations were approximately determined by measurements
from existing property lines and paved roads.
A geologist from our office conducted the field exploration and classified the soil
conditions encountered, maintained a log of each test exploration, obtained
representative soil samples, and observed pertinent site features. All soil samples were
visually classified in accordance with the Unified Soil Classification System (USCS).
Representative soil samples obtained from the explorations were placed in closed
containers and taken to our laboratory for further examination and testing. As a part of
the laboratory testing program, the soil samples were classified in our in house laboratory
based on visual observation, texture, plasticity, and the limited laboratory testing
described below.
Moisture Content Determinations
Moisture content determinations were performed in accordance with ASTM D2216-10
Standard Test Methods for Laboratory Determination of Water (Moisture) Content of Soil
and Rock by Mass (ASTM D2216) on representative samples obtained from the
exploration in order to aid in identification and correlation of soil types. The moisture
content of typical sample was measured and is reported on the test pits Logs.
Grain Size Analysis
A grain size analysis indicates the range in diameter of soil particles included in a
particular sample. Grain size analyses was determined using D6913-04{2009) Standard
Test Methods for Particle-Size Distribution (Gradation) of Soils Using Sieve Analysis (ASTM
D6913) on three of the samples.
• •• ·~-l'HI r::vrnnnn,
Project Name: Nordic Ridge Plat II • Test Pit No.: TP-1
Project Number: 2015-097 I ... Sheet 1 of 1
Client: Nordic Ridge, LLC RILEYGROUP
Date(s) Excavated: 7/1/2015 Logged By ELW Surface Conditions: Grass
Excavation Method: Backhoe Bucket Size: N/A Total Depth of Excavation: 8 feet bgs
Excavator Type: Rubber Tire Backhoe Excavating Contractor: Harbor Point Approximate
Excavatina Sutiace Elevation
Groundwater Level: Not Encountered ~:~:!~~) Grab Compaction Method Bucket
Test Pit Backfill: Cuttings Location 17709116th Avenue Southeast, Renton, Washington
~ ~
J t 0
~ t 0,
w 3 C ~ f-z
0 w j1 en 0
~ ~ <a ~ en ic
a. ~ u a.
j1 w en I'! MATERIAL DESCRIPTION REMARKS AND OTHER TESTS Ul 0 en en :, C)
-0 TPSL Topsoil rB Brown silty SAND with some gravel, loose to medium
dense, moist
I 16% moisture, 24% fines
SM Gray silty SAND with some gravel. medium dense to
dense, moist (Weathered Till)
I 16% moisture
I-Iron oxide staining
-5-SM Gray silty SAND with some gravel, dense to very dense,
moist (Glacial Till)
] -Becomes very dense
10% moisture
Test Pit terminated at 8'
-10
The Rile Grou y p, Inc.
17522 Bothell Way NE, Bothell, WA 98011
Project Name: Nordic Ridge Plat
Project Number: 2015-097
I I a Test Pit No.: TP-2
I~-s t RILEYGROUP heet 1 o 1
Client: Nordic Ridge, LLC
Date{s) Excavated: 7/1/2015
Excavation Method: Backhoe
Excavator Type: Rubber Tire Backhoe
Groundwater Level: Not Encountered
Test Pit Backfill: Cuttings
~ ID a
~ J 1 t C,
ID 0
C ~ >-z ..J
0 ID ID Cl) u
~ £ g ! Cl) :2
0. ~ () 0.
.9! ID Cl) ~
w 0 Cl) Cl) ::, CJ
-0 TPSL
SM
SM
I
SM
-,-
I
-10
Logged By ELW
Bucket Size: NIA
Harbor Point
Excavating Contractor: Excavatina
Surface Conditions: Grass
Total Depth of Excavation: 7 feet bgs
Approximate
Swface Elevation
Compaction Method Bucket
Location 17709116th Avenue Southeast, Renton, Washington
MATERIAL DESCRIPTION REMARKS AND OTHER TESTS
Topsoil
Brown silty SAND with trace gravel. loose to medium
dense, moist
Gray silty SAND with some gravel, medium dense to
dense, moist (Weathered Till)
14% moisture
-Iron oxide staining
Gray silty SAND with some gravel, very dense, moist
(Glacial Till)
I--
11 % moisture
Test pit terminated at 7'
The Riley Group, Inc.
17522 Bothell Way NE, Bothell, WA98011
Project Name: Nordic Ridge Plat ••• Test Pit No.: TP-3
Project Number: 2015-097 ·~-Sheet 1 of 1
Client: Nordic Ridge, LLC RILEYGROUP
Date{s) Excavated: 7/112015 Logged By ELW Surface Conditions: Grass
Excavation Method: Backhoe Bucket Size: N/A Total Depth of Excavation: 7 feet bgs
Excavator Type: Rubber Tire Backhoe Excavating Contractor: Harbor Point Approximate
Excavatina Surface Elevation
Groundwater Level: Not Encountered t~~:!~;} Grab Compaction Method Bucket
Test Pit Backfill: Cuttings Location 17709116th Avenue Southeast, Renton, Washington
'di .ll 0
,!!!, ;; .~ ~ t "' 0
C ,!!!, f-z ..,
0 ~ .QI Cl) u .. .c Q Cl) ~ "' ~ ~ g-g u
Cl) ~ MATERIAL DESCRIPTION REMARKS AND OTHER TESTS UJ 0 Cl) Cl) ::, " -0 TPSL Topsoil
SM Brown silty SAND with trace gravel, loose lo medium
dense, moist
IT 11 % moisture
SM Gray silty SAND with some gravel, medium dense to
dense, moist (Weathered Till)
I 14% moisture
Iron oxide staining
SM Gray silty SAND with some gravel, very dense, moist
-5-
(Glacial Till) -
I 10% moisture
f---
Test Pit terminated at 7'
-10
Ril ,oo The eyG p, '"'· 17522 Bothell Way NE, Bothell, WA 9801 i
Project Name: Nordic Ridge Plat II • Test Pit No.: TP-4
Project Number: 2015-097 .... Sheet 1 of 1
Client: Nordic Ridge, LLC RILEYGROUP
Date(s) Excavated: 7/1/2015 Logged By ELW Surface Conditions: Grass
Excavation Method: Backhoe Bucket Size: NIA Total Depth of Excavation: 7.5 feet bgs
Excavator Type: Rubber Tire Backhoe Excavating Contractor:
Harbor Point Approximate
Excavatina Surface Elevation
Groundwater Level: Not Encountered t~~:=(~} Grab Compaction Method Bucket
Test Pit Backfill: Cuttings Location 17709116th Avenue Southeast, Renton, Washington
~ w 0 J E ,!!!, ~ ~ E .3 C ,!!!, 1--iii 0 Q) .91 0
~ ~ l Cf) ~ ~ f l; C. u I'! w Cf) MATERIAL DESCRIPTION REMARKS AND OTHER TESTS w 0 Cf) Cf) ::, C)
-0 TPSL Topsoil
SM Brown silty SAND with trace gravel, loose to medium
dense, moist
I 9% moisture
SM Gray silty SAND with some gravel, dense, moist
(Weathered Till)
Iron oxide staining
I 15%, moisture
-,-----.., Gray silty SAND with some gravel, very dense, moist
(Glacial Till)
I 12% moisture
Test Pit terminated at 7.5'
-10
TheRil G= ey p, '"'· 17522 Bothell Way NE, Bothell, WA98011
Project Name: Nordic Ridge Plat II • Test Pit No.: TP-5
Project Number: 2015-097 I ~-Sheet 1 of 1
'Client: Nordic Ridge, LLC RILEYGROUP
Date(s) Excavated: 7/1/2015 Logged By EL W Surface Conditions: Grass
Excavation Method: Backhoe Bucket Size: N/A Total Depth of Excavation: 6.5 feet bgs
Excavator Type: Rubber Tire Backhoe Excavating Contractor: Harbor Point Approximate
Excavatina Surface Elevation
Groundwater level: Not Encountered t:~!~~l Grab Compaction Method Bucket
Test Pit Backfill: Cuttings Location 17709116th Avenue Southeast, Renton, Washington
~ w
,1i ~ 0
~ .; t "' 0
C ~ f--z .J
0 ID ID (/) " .. £ ] l (/) :g_ "' > 0. 0
ID " "' (/) ~ MATERIAL DESCRIPTION REMARKS AND OTHER TESTS uJ 0 (/) (/) :::, (!) -a TPSL Topsoil
SM Brown silty SAND with trace gravel, loose to medium
dense, moist
] 9% moisture
SM Gray silty SAND with some gravel. dense, moist
(Weathered Till)
] -lron oxide staining
11 % moisture
SM Gray silty SAND with trace gravel, very dense, moist
-(Glacial Till) -,-a ....
12% moisture, 35% fines
Test Pit terminated at 6.5'
-10
The Riley Group, Inc.
17522 Bothell Way NE. Bothell, WA98011
Project Name: Nordic Ridge Plat II • Test Pit No.: TP-6
Project Number: 2015-097 I ... Sheet 1 of 1
Client: Nordic Ridge, LLC RILEYGROUP
Date(s) Excavated: 7/1/2015 Logged By ELW Surface Conditions: Grass
Excavation Method: Backhoe Bucket Size: NIA Total Depth of Excavation: 6 feet bgs
Excavator Type: Rubber Tire Backhoe Excavating Contractor: Harbor Point Approximate
Excavatina Surface Elevation
Groundwater Level: Not Encountered ~:~~~~) Grab Compaction Method Bucket
Test Pit Backfill: Cuttings Location 17709116th Avenue Southeast, Renton, Washington
~ "' 0
~ _g ~ t 0,
"' 0
C ~ .... z -'
0 '" ~ <f) 0
~ ~ I f <f) t 0. (.) i" '" <f) REMARKS AND OTHER TESTS w 0 <f) <f) ::, " MATERIAL DESCRIPTION
-0 TPSL Topsoil 11-· .. -··----·-~·-dense, moist
I 11 % moisture
~ Gray silty SAND with some gravel, medium dense to
dense, moist (Weathered Till)
I I-Iron oxide staining
12% moisture
SM Gray silty SAND with some gravel, very dense. moist
-,-I ,... (Glacial Till) -
12% moisture
Test Pit terminated at 6'
-10
The Rile Groo y P. '"'· 17522 Bothell Way NE, Bothe!!, WA 98011
Project Name: Nordic Ridge Plat
Project Number: 2015-097
I I • Test Pit No.: TP-7 !LE~G9 Sheet 1 of 1
Client: Nordic Ridge, LLC
Date(s} Excavated: 7/112015
Excavation Method: Backhoe
Excavator Type: Rubber Tire Backhoe
Groundwater Level: Not Encountered
Test Pit Backfill: Cuttings
~ " ~ a
~ § t "' a, 0
~ ~ ... z __,
i .91 .91 "' u
~ a. "' ! a. ~ ~ 0
.91 " "' i5 UJ 0 "' "' ::,
TPSL
Logged By ELW
Bucket Size: NIA
Harbor Point
Excavating Contractor: Excavatino
Surface Conditions: Grass
Total Depth of Excavation: 8 feet bgs
Approximate
Surface Elevation
Compaction Method Bucket
Location 17709 116th Avenue Southeast, Renton, Washington
MATERIAL DESCRIPTION
Topsoil
Brown silty SAND with trace gravel, loose to medium
dense, moist
Gray silty SAND with some gravel, medium dense to
dense. moist (Weathered Till)
Iron oxide staining
Gray silty SAND with some gravel, very dense, moist
(Glacial Till)
Test Pit terminated at 8'
REMARKS AND OTHER TESTS
10% moisture
10% moisture, 20% fines
12% moisture
10,--'--'---'---'---'---------------------'-----------
The Riley Group, Inc.
17522 Bothell Way NE, Bothell, WA 98011
Project Name: Nordic Ridge Plat
Project Number: 2015-097
I I • Test Pit No.: TP-8
• , .. s f RILEYGROUP heet 1 o 1
Client: Nordic Ridge, LLC
Date(s) Excavated: 7/112015
Excavation Method: Backhoe
Excavator Type: Rubber Tire Backhoe
Groundwater Level: Not Encountered
Test Pit Backfill: Cuttings
'$' :;;
" I 0
,1s '$' ! 0,
C ,1s .... z .3
0 _g, _g, (/) 0
~ ~ (/) :c " ~ ~ "-~ u "-
" (/) ~
w 0 (/) (/) ::, C)
TPSL
Logged By ELW
Bucket Size: NIA
Harbor Point Excavating Contractor: Excavatin
Surface Conditions: Grass
Total Depth of Excavation: 6.5 feet bgs
Approximate
Surface Elevation
Compaction Method Bucket
Location 17709 116th Avenue Southeast, Renton, Washington
MATERIAL DESCRIPTION
Topsoil
Brown silty SAND with trace gravel. loose to medium
dense, moist
Brown silty SAND with some gravel, medium dense to
dense, moist (Weathered Till)
Iron oxide staining
Gray silty SAND with some gravel, very dense, moist
(Glacial Till)
Test Pit terminated at 6.5'
REMARKS AND OTHER TESTS
9% moisture
13% moisture
11% moisture
10~~-~--~~-------------------~---------~
The Riley Group, Inc.
17522 Bothell Way NE, Bothell, WA 9801 t
Project Name: Nordic Ridge Plat
Project Number: 2015-097
Client: Nordic Ridge, LLC
1i;' :;;
0
~ 1i;' ! 1 I _§'
C ~ z
0 w ;!! U) 0
~ ~ Q U) :g_
C. u
Key to Logs ••• ·~-RILEYGROUP Sheet 1 of 1
~ ji ~ !" w U)
w 0 U) U) :::, " MATERIAL DESCRIPTION REMARKS AND OTHER TESTS
w L?..I d w l.§..1 l.§..1 w
COLUMN DESCRIPTIONS
Depth (feet): Depth in feet below the ground surface. ~ Elevation (feet): Elevation (MSL, feet).
Sample Type: Type of soil sample collected at the depth interval
shown.
[fil uses Symbol: uses symbol of the subsurface material.
[fil Graphic Log: Graphic depiction of the subsurface material
encountered.
[r] MATERIAL DESCRIPTION: Description of material encountered.
[!] Sample Number: Sample identification number.
FIELD AND LABORATORY TEST ABBREVIATIONS
CHEM: Chemical tests to assess corrosivity
COMP: Compaction test
CONS: One-dimensional consolidation test
LL: liquid limit, percent
MATERIAL GRAPHIC SYMBOLS
• Silty SAND (SM)
TYPICAL SAMPLER GRAPHIC SYMBOLS
~ Auger sampler
~ Bulk Sample
lfl 3-inch-OD California w/ !!I brass rings
GENERAL NOTES
rn CME Sampler
1-·
I_ L Grab Sam pie
12.5-inch-OD Modified
California w/ brass liners
May include consistency, moisture, color, and other descriptive
text
[!) REMARKS AND OTHER TESTS: Comments and observations
regarding drilling or sampling made by driller or field personnel.
Pl: Plasticity Index, percent
SA: Sieve analysis (percent passing No. 200 Sieve)
UC: Unconfined compressive strength test, Ou, in ksf
WA: Wash sieve (percent passing No. 200 Sieve)
~ Pitcher Sample
~ 2-inch-OD unlined split
~ spoon (SPT)
IV1 Shelby Tube (Thin-walled, rJ fixed head)
OTHER GRAPHIC SYMBOLS
'v Water level {at time of drilling, ATD)
----? Water level {after wa1t1ng)
Minor change in material properties within a
stratum
--lnferred/gradational contact between strata
-? -Queried contact between strata
1: Soil classifications are based on the Unified Soil Classification System. Descriptions and stratum lines are interpretive, and actual lithologic changes may be
gradual. Field descriptions may have been modified to reflect results of lab tests.
2: Descriptions on these logs apply only at the specific boring locations and at the time the borings were advanced. They are not warranted to be representative
of subsurface conditions at other locations or times.
The Riley Group, Inc
17522 Bothell Way NE, Bothell, WA 98011
THE RILEY GROUP, INC.
17522 Bothell Way NE
Both<(II, WA 98011
PROJECT TITLE
PROJECT NO.
TECH/TEST DATE ELW
GRAIN SIZE ANALYSIS
ASTM 0421, 0422, 01140, 02487, 06913
Nordic Ridge Plat SAMPLE ID/TYPE
2015-097 SAMPLE DEPTH
7/1/2015 DATE RECEIVED
PHONE: {425) 415-0551
FAX: (425) 415-0311
TP-1 I
2' I
7/1/2015 I
WATER CONTENT {Delivered Moisture) Total Weight Of Samgle Used For Sieve Corrected For H}'.groscogic Moisture
Wt Wet Soil & Tare (gm) (wl) 391.8 Weight Of Sample (gm)
Wt Dry Soil & Tare (gm) (w2) 339.2 Tare Weight (gm)
Weight ofTare (gm) (w3) 15.6 (W6) Total Dry Weight (gm)
Weight of Water (gm) (w4=wl-w2) 52.6 SIEVE ANALYSIS
Weight of Dry Soil (gm) (w5=w2-w3) 323.6 Cumulative
Moisture Content (%) (w4/w5)*100 16 WtRet (Wt-Tare) (%Retained) % PASS
+Tare f!wt ret[w6j•100} (100-%ret)
% COBBLES 0.0 12.0" 15.6 0.00 0.00 100.00
% CGRAVEL 0.0 3.0" 15.6 0.00 0.00 100.00
% F GRAVEL 19.1 2.5"
% CSAND 9.4 2.0"
%MSAND 19.1 1.5" 15.6 0.00 0.00 100.00
% FSAND 28.6 1.0"
% FINES 23.8 0.75" 15.6 0.00 0.00 100.00
%TOTAL 100.0 0.50"
0.375" 51.9 36.30 11.22 88.78
DlO(mm) § #4 77.4 61.80 19.10 80.90
D30(mm) #10 107.9 92.30 28.52 71.48
D60(mm) #20
Cu #40 169.7 154.10 47.62 52.38
Cc #60
#100 240.9 225.30 69.62 30.38
#200 262.1 246.50 76.17 23.83
PAN 339.2 323.60 100.00 0.00
12· 3" 2" 1".75" .375" #4 #10 #20 #40 #60 #100 #200
% 100 ,, l I "-i 90
I I I I I I 80 -r------I -~ I ~" I 'I p 70 I ------I I -....... I ! ' A 60 I I 'I s so I-"'I-.. 1 ! 40 s 30 '-ii
I I I I 20
N 10 I I I i I
0 I I I 1
G
1000 100 10 1 0.1 0.01
Grain size in millimeters
DESCRIPTION Silty SAND with some gravel
uses SM
Prepared For: Reviewed By: KMW
Nordic Ridge, LLC
••• ••• RILEYGROUP
339.2 I
15.6 I
323.6 I
cobbles
coarse gravel
coarse gravel
coarse gravel
coarse gravel
coarse gravel
fine gravel
fine gravel
fine gravel
coarse sand
medium sand
medium sand
fine sand
fine sand
fine sand
fines
silt/clay
I
-
I
0.001
THE RILEY GROUP, INC.
17522 Bothell Way NE
Bothe,11, WA 98011
PROJECT TITLE
PROJECT NO.
TECH/TEST DATE ELW
GRAIN SIZE ANALYSIS
ASTM D421, D422, D1140, D2487, D6913
Nordic Ridge Plat SAMPLE ID/TYPE
2015-097 SAMPLE DEPTH
7/1/2015 DATE RECEIVED
PHONE: {425) 415-0551
FAX: {425) 415-0311
TP-5
5•
7/1/2015
I
I
I
WATER CONTENT (Delivered Moisture) Total Weight Of Samgle Used For Sieve Corrected For Hygroscogic Moisture
Wt Wet Soil & Tare (gm) (wl)
Wt Dry Soil & Tare (gm) (w2)
Weight ofTare (gm) (w3)
Weight of Water (gm) (w4=wl-w2)
Weight of Dry Soil (gm) (w5=w2-w3)
Moisture Content(%) (w4/w5)'100
% COBBLES 0.0
% CGRAVEL 7.0
% FGRAVEL 4.5
% CSAND 3.0
% M SAND 10.7
% F SAND 40.3
% FINES 34.S
% TOTAL 100.0
DlO(mm) ~ D30(mm)
D60(mm)
Cu
Cc
,,-,. ,. 1"75"
% 100 c--90 ->--
80
p 70
A 60
s so
40
~
s 30 r-----
I 20
N 10
G 0
1000 100
DESCRIPTION Silty SAND with trace gravel
uses SM
Prepared For:
Nordic Ridge, l.LC
490.4 Weight Of Sample (gm)
439.0 Tare Weight (gm)
15.4 (W6) Total Dry Weight (gm)
51.4 SIEVE ANALYSIS
423.6 Cumulative
12 WtRet (Wt-Tare) {%Retained} % PASS
+Tare {[wt ret{w6J•100} (100-%retl
12.0" 15.4 0.00 0.00 100.00
3.0" 15.4 0.00 0.00 100.00
2.5"
2.0"
1.5" 15.4 0.00 0.00 100.00
1.0"
0.75" 45.0 29.60 6.99 93.01
0.50"
0.375" 56.9 41.50 9.80 90.20
#4 64.0 48.60 11.47 88.53
#10 76.6 61.20 14.45 85.55
#20
#40 122.0 106.60 25.17 74.83
#60
#100 257.1 241.70 57.06 42.94
#200 292.9 277.50 65.51 34.49
PAN 439.0 423.60 100.00 0.00
375" #4 #10 #20 #40 #60 #100 #200
! -i
i ~ i i
I i
I "
-rt
I I..._ I
! I l ------I
--
11 I j
--! I
10 1 0.1 O.Ql
Grain size in millimeters
Reviewed By: KMW
••• . , ..
RILEYGROUP
439.0 I
15.4 I
423.6 I
cobbles
coarse gravel
coarse gravel
coarse gravel
coarse gravel
coarse gravel
fine gravel
fine gravel
fine gravel
coarse sand
medium sand
medium sand
fine sand
fine sand
fine sand
fines
silt/clay
I
i
---1
:
I
I
0.001
THE RILEY GROUP, INC.
17522 Bothell Way NE
Both<;II, WA 98011
PROJECT TITLE
PROJECT NO.
TECH/TEST DA TE ELW
GRAIN SIZE ANALYSIS
ASTM D421, D422, D1140, D2487, D6913
Nordic Ridge Plat SAMPLE ID/TYPE
2015-097 SAMPLE DEPTH
7/1/2015 DATE RECEIVED
PHONE: {425) 415-0551
FAX: (425) 415-0311
TP-7 I
4' I
7/1/2015 I
WATER CONTENT (Delivered Moisture! Total Weight Of Sam12le Used For Sieve Corrected For Hygrosco~ic Moisture
Wt Wet Soil & Tare (gm) (wl) 329.5 Weight Of Sample (gm) 300.7
Wt Dry Soil & Tare (gm) (w2) 300.7 Tare Weight (gm) 15.6
Weight ofTare (gm) (w3) 15.6 (W6) Total Dry Weight (gm) 285.1
Weight of Water (gm) (w4=wl-w2) 28.8 SIEVE ANALYSIS
Weight of Dry Soil (gm) (w5=w2-w3) 285.1 Cumulative
Moisture Content (%} (w4/w5)*100 10 WtRet (Wt-Tare) !%Retained} %PASS
+Tare f!wt retlw6j"100} (100-%ret)
% COBBLES 0.0 12.0" 15.6 0.00 0.00 100.00 cobbles
% CGRAVEL 12.1 3.0" 15.6 0.00 0.00 100.00 coarse gravel
% F GRAVEL 13.3 2.5" coarse gravel
%CSAND 7.4 2.0" coarse gravel
% MSAND 17.4 1.5" 15.6 0.00 0.00 100.00 coarse gravel
% F SAND 29.5 1.0" coarse gravel
% FINES 20.3 0.75" 50.0 34.40 12.07 87.93 fine gravel
% TOTAL 100.0 0.50" fine gravel
0.375" 68.3 52.70 18.48 81.52 fine gravel
DlO(mm) § #4 87.9 72.30 25.36 74.64 coarse sand
D30(mm) #10 109.0 93.40 32.76 67.24 medium sand
D60(mm) #20 medium sand
Cu #40 158.7 143.10 50.19 49.81 fine sand
Cc #60 fine sand
#100 223.S 207.90 72.92 27.08 fine sand
#200 242.8 227.20 79.69 20.31 fines
PAN 300.7 285.10 100.00 0.00 silt/clay
12· 3• ,. 1".75" .375" .. "10 #20 1140 #60#100 #200
% 100 I I I I
90 l ' I
I --.... ! I i I 80 I i,1 f-I p 70 I I 1--
60 I ~ --1 ------~ J j A I I
s 50 !· I r--I 40 ----,r " I -1--s 30
I 20
I I
----I ----I
• I I I ; I +t--N 10 I I I I
G 0
1000 100 10 1 0.1 0.01 0.001
Grain size in millimeters
DESCRIPTION
uses
Prepared For:
Nordic Ridge, LLC
Silty SAND with some gravel
SM I
Reviewed By: KMW
••• llWI
RILEYGROUP
I
I
I
7. OTHER PERMITS
The National Pollutant Discharge Elimination System (NPDES) permit will be prepared
with the final construction plans.
This project will also require the following permits:
Building Permits
Clearing & Grading Permits
33
8. CSWPPP ANALYSIS AND DESIGN
CSWPPP analysis and design will be provided with final engineering.
34
9. BOND QUANTITIES, FACILITY SUMMARIES, AND DECLARATION OF
COVENANT
Bond Quantities, Facility Summaries, and Declaration of Covenant will be provided in the
final TIR.
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10. OPERATIONS AND MAINTENANCE MANUAL
The Operations and Maintenance Manual will be provided in the final TIR.
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