Lake_Youngs-Perimeter_Dike_Liquefaction_Potential_Report_1985.pdf

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LAKE YOUNGS DAM

IMPROVEMENT PROJECT

PERIMETER DIKE

LIQUEFACTION POTENTIAL

REPORT #3E

Seattle Water Department

AUGUST 1985 ----~~~

Sf ~, EIWiCO

EBASCO SERVICES

INCORPORATED

JO~,ffDlflJ

LAKE YOUNGS DAM

IMPROVEMENT PROJECT

PERIMETER DIKE

LIQUEFACTION POTENTIAL

REPORT #3E

Seattle Water Department

AUGUST 1985

EBASCO

EBASCO SERVICES

INCORPORATED

EBASCO SERVICES INCORPORATED

10900 NE 8th Street. Bellevue. WA 98004-4405. (2061451 -4500

Mr. Syed Zaidi Seattle Water Department 821 Second Avenue Seattle, Washington 98104

Dear Syed:

August 23, 1985

SUBJECT: LAKE YOUNGS DAM IMPROVEMENT PROJECT

PERIMETER DIKE LIQUEFACTION POTENTIAL

EBAOCO

Transmitted herewith are ten (10) final copies of the "Perimeter Dike Liquefaction Potential" Report. In response to the comments received in your letter of July 24, 1985, the following is provided. The cost estimate of $40 mill i on for the water treatment facil ity is a rough estimate for a faci 1 ity designed to handle the inflow of approximately 250 mgd. Any further refine ments in cost would require at least a reconnaissance-level cost estimate which is beyond the present scope of the work. The plant will be the sand filtration type and include a sedimentation pond with flocculant or polymer addi ti on. The work of our subconsultant, Economi c and Engineeri ng Servi ces, is included in the "Inlet Dam and Honey Creek Diversion Predesign Report , " as it is more pertinent to that study. The description of the method of con struction and location of the dike replacement has been enhanced in the text.

If the lake level drawdown was limited to 486 feet, the costs would increase substantially to $6 million. This would include approximately $2 million for earthwork and $4 million for sheet pile cofferdams to allow construction to proceed in the dry.

I woul d 1 ike to acknowl edge Converse Consultants, for thei r contri buti on to the work effort covering both the field investigations and laboratory testing, and Engineering and Economic Services , for their contributions pertaining to the water treatment facility .

If you have any further questions, please contact Mike Pavone at 451-4592 .

DS/MK/ dl h/3960C Enclosures

Sincerely, E~~O SE~VICEt~ ~ IN~ORPORATED

/!J/~//I, Don Smith Project Manager

2127C

LAKE YOUNGS DAM IMPROVEMENT PROJECT

PERIMETER DIKE LIQUEFACTION POTENTIAL

FOR

SEATTLE WATER DEPARTMENT

BY

AUGUST. 1985

l.0 l.1 l.2 l.3 l.4

2.0 2.1 2.2 2.3 2.4

REFERENCES

APPENDIX

Figure No.

LAKE YOUNGS IMPROVEMENT PROJECT

PERIMETER DIKE LIQUEFACTION POTENTIAL

TABLE OF CONTENTS

SUMMARY

Introduction Scope Conclusions Reconmendations

DISCUSSION

Field Studies Laboratory Studies Liquefaction Potential Perimeter Dike Improvement Alternatives

LIST OF FIGURES

1 PERIMETER BORING LOCATION PLAN

2 PERIMETER BORINGS - GENERALIZED PROFILE

3 CLASS I EARTHQUAKE-LIQUEFACTION POTENTIAL

4 CLASS II EARTHQUAKE - LIQUEFACTION POTENTIAL

COPYRIGHT (c) 1985, CITY OF SEATTLE, SEATTLE WATER DEPARTMENT

2127C i

1.0 SUMMARY

SEATTLE WATER DEPARTMENT

LAKE YOUNGS PROJECT

PERIMETER DIKE LIQUEFACTION POTENTIAL

1.1 Introduction

This report summarizes the results of studies to assess the seismic stability of the Lake Youngs perimeter dikes. The study was prompted by potential impacts to the lake water quality resulting from an earthquake induced failure of these dikes. A preliminary cost estimate for upgrading the dikes is provided.

The seismic integrity of the perimeter dikes have been suspect for many years. They experienced earthquake damage in 1949 and 1965, and their integrity was questioned by Converse Consultants in their 1980 Report on Dike Reconnaissance, (Reference 1). In that study, Converse recommended that backup dikes be considered in areas where failure of the existing dikes would allow water to flow off Water Department property . This recommendation was accepted and implemented.

Renewed concern about the seismic stability of the perimeter dikes developed as a result of Ebasco predesign efforts at the Inlet Dam area. These studies concluded that Cascades Dam could fail during an earthquake and considerable expenditures would be required to construct the necessary project modifications to address the safety, as well as the water quality impacts of a

Cascades Dam failure. Thus prior to committing to an Inlet Dam project alternative which addresses the water quality and safety impacts due to a failure of Cascades Dam, the Water Department requested a limited study be performed to assess the seismic stability of the perimeter dikes and potential water quality impacts in the event of their failure.

?lnC 6/10/85 1 .

The assessment presented herein consists of a determination of the earthquake recurrence interval that would initiate a liquefaction failure of the dikes.

That recurrence interval is then compared to the Cascades Dam studies to develop a plan that is compatible with the entire project.

1.2 Scope

To assess the seismic stability of the Lake Youngs perimeter dikes, sixteen borings were drilled along the dike perimeter road. Standard penetration tests (SPT) were performed in each of the borings to retrieve samples for laboratory testing. The field SPT results together with the laboratory tests were correlated with empirical relationships to develop the strength available to resist earthquake loads. With the stresses induced by a given earthquake computed, safety factors against liquefaction were determined. This approach was used for the Class I earthquake (10,000 year recurrence interval), and the Class II earthquake (100 year recurrence interval).

As a result of these liquefaction analyses, a very preliminary concept for upgrading the dikes was developed, together with schedule and costs. In addition, an order-of-magnitude cost for a water treatment plant to remove suspended solids from the lake water resulting from a dike liquefaction was developed.

1.3 Conclusions

The results of this study confirm the initial subsurface interpretations presented in the Report on Dike Reconnaissance by Converse Consultants in 1980. Of the sixteen borings placed within the perimeter dikes, all exhibit lones of loose sandy materials. Though the borings are widely spaced it is probable that these lones are present at all dike sections. The thickness of these lones vary from a few feet to possibly greater than the maximum observed thickness of 12 feet.

In the event of liquefaction the materials comprising this lone, as well as perimeter road fill material above this zone would be introduced into the reservoir, and swampy areas downstream of the perimeter dikes would be inundated and become part of the reservoir. The SPT data and liquefaction 2127C &/10/85

-2-analysis of this loose zone indicates that liquefaction of these loose sandy materials under Class I (10,000 year) and Class II (100 year) earthquakes is probable. Therefore, the perimeter dikes are more likely to experience a liquefaction failure than the Cascades Dam, which was shown to require a 200-year recurrence earthquake to cause a failure.

Preliminary cost estimates to replace dike sections prone to liquefaction range from $1.5 million to $2 .0 million and require reservoir drawdown to elevation 480 for three to four months. An order-of-magnitude cost of a waste treatment facility would be approximately $40 million. However, operational and maintenance considerations would increase the cost significantly .

1.4 Recorrmendations

Public safety is not an issue in the event of an earthquake-induced failure of the Lake Youngs perimeter dikes . Therefore, to recommend a course of action for addressing the structural deficiencies of these dikes, capital costs, construction schedule and impacts on the operation of the project must be considered. Other technical considerations include the following:

2127C o The determination of the liquefaction potential of soil formations is not an exact science.

o The ability to predict with certainty the mode of dam response to the assumed earthquake events, (e.g., minor cracking, upstream slumping, crest subsidence, or complete flow slide), is difficult, if not impossible.

o The duration of time that the dam, or portion thereof stays in a liquefied state cannot be adequately predicted.

o The dikes have been subjected to major earthquakes in the past. While substantial cracking was observed along some of the dikes that may have been liquefaction-related, none of the dikes suffered complete failure .

&/10/85

- 3-

Considering all these factors it is recommended at this time that no special action be taken to upgrade the perimeter dikes . All the ·complete repair" solutions presented require considerable expenditures and, in the case of the dike reconstruction schemes, will require the lake to be drawn down for approximately 3 months to allow construction.

7177C 6/10/85 4 .

2.0 DISCUSSION

2.1 Field Studies

A total of sixteen boreholes were drilled through the perimeter dike crests and into the dense glacial foundation at locations shown in Figure 1.

Detailed boring logs are presented in the Appendix. Boreholes were located in areas that experienced distress during previous earthquakes and just upstream of low-lying "wet" areas. The holes were advanced using a tricone roller bit and stabilized during drilling with drilling mud. Standard Penetration Tests

(SPT) were performed at 2-1/2 foot intervals.

A generalized profile consists of 1.5 to & feet of medium dense to dense sand and gravel road fill, 2 to 11 feet of very loose to loose sands or silty sands with varying quantities of gravel, and medium dense to very dense sands and silty sands with varying amounts of gravel (i.e ., glacial till). Sample recovery of loose materials proved difficult with the standard penetration sample spoon or with a driven shelby tube. Redrilling at selected locations using a thick walled ring sampler was necessary and met with some success in retrieving loose materials .

All sixteen borings had zones of loose, liquefaction-prone sandy materials, ranging in thickness from 2 to 11 feet . Borings P-3 and P-& registered penetration data less than 1 blow/foot and boring P-5 had an B- foot loose zone with blow counts ranging from 1 to 2 blows per foot .

Generalized subsurface profiles are shown in Figure 2, with abbreviated soil descriptions. Zones of loose and liquefaction -prone materials are shown shaded.

2.2 Laboratory Studies

The results of laboratory soils gradations are presented in the Appendix .

Soil materials consist of gravelly, silty sands. The silt content varies from

2121C &/10/85 -5-

8 to 3& percent and the gravel content from 4 to 54 percent. The mean gradation size (D50) for each gradation curve ranges from 0.2 mm to 0.9 mm, averaging 0.4 mm. More importantly, the silt size materials are probably similar if not identical to the glacial flour observed in the laboratory sedimentation tests performed for Cascades Dam (Reference 2).

2.3 Liquefaction Potential

The most recent paper by H. Seed and I. Idriss (Reference 3) addressing the evaluation of liquefaction potential provided the basis for the analysis performed for this study. Determination of representative liquefaction potential was based on data obtained from boring P-2. Boring P-2 was taken as having "average" SPT within "loose" sandy zones. At the boring P-2 location, the thickness of dike material is approximately 15 feet. Note that borings

P-3, P-5, P-&, P-ll, and P-15 had lower penetration data than boring P-2 ranging from less than one to two blOWs/foot, indicating essentially zero resistance to any seismic loading. Liquefaction analyses based on these data would be redundant.

For analysis purposes, dike crest and phreatic surface elevations were taken at 49& and 491, respectively. The phreatic surface at El. 491 corresponds to a water level near the upstream face of the dike.

Earthquake magnitudes and their associated return periods and accelerations used in the liquefaction analysis are as follows:

Magnitude Peak Horizontal Ground Acceleration Retu rn Pe ri od

Class I

7.0 0.39g 10,000 years

Class II

5.& 0.12g 100 years

This earthquake data was recently updated from seismicity studies performed by

Converse in 1980 . The details of the update are presented in the Inlet Dam and Honey Creek Diversion Predesign Report.

2127C &/10/85

The results of the liquefaction analysis based on the penetration data of boring P-2 is shown in Figures 3 and 4. Plotted on these figures are curves representing the soil strength under a given magnitude earthquake, the applied stresses induced by the same magnitude earthquake, and a plot of the factor of safety against liquefaction. Where the applied stresses are greater than the available strength , the factor of safety will be less than unity and one can expect liquefaction to occur. As seen in Figure 3, under Class I earthquake loads the entire 8-foot zone of loose materials can be expected to liquefy with the average factor of safety with respect to liquefaction on the order of

0.20. Under Class II loads the factors of safety remains unsatisfactory over a significant portion of the embankment height as shown in Figure 4. An average safety factor to resist the Class II loading is 0 .6.

2.4 Perimeter Dike Improvement Alternatives

Various alternative schemes and their associated costs were examined to improve or replace those dike sections (approximately 20,000 lineal feet) spread throughout the perimeter of the lake vulnerable to liquefaction failure. All alternatives examined require reservoir drawdown to approximately El . 480. Schemes which involved in situ dike improvement included chemical grouting, and vibro replacement . Vibro-replacement is the most technically feasible but is prohibitively expensive at approximately $4 million . Due to the percentage of silt size materials (up to 36 percent fines) the chemical grouting is only marginally feasible and are also very expensive (a minimum of $3 million). A scheme utilizing steel sheeting to prevent the dikes from slumping into the reservoirs is estimated to cost between $3 and $4 million .

Replacement of the liquefaction prone dike sections is technically feasible and the least expensive option examined. The method of drawing the lake down to El. 480, removing, and stockpiling the ensuing loose dike material with large earth-moving equipment and reconstructing the dikes with the original fill in a well-compacted state back in their original alignment. Estimated costs range from $1.5 million to $2 million, depending upon re-use of exi sting dike materials or hauling from on-site borrow sources.

2127C 8/21/85 -7-

REFERENCES

1. Report on Dike Reconnaissance, lake Youngs Reservoir - Reservoir Seismic

Slope Stability Analysis, Converse Consultants, September 30, 1980.

2. "Potential Impact of Cascades Dam Failure on the Water Quality in lake Youngs," Economic and Engineering Services, Inc., February 25, 1985.

3. "Evaluation of liquefaction Potential of Sand Deposits 8ased on Observations of Perfonmance in Previous Earthquakes," Seed and Idriss, October 1981 .

2127C 6/10/85 -8-

FIGURES

2127C 6/10/85 -9-

PROPERTY LINE 2

P-5

P -6

P- \ LAKE YOUNGS

RESERVOIR

p-g

N

SHADY LAKE

CASCADES

DAM

OUTLET

(SOUTH) ~

DAM

I"

L P-IO ",

L .. __ .~

00 800 0 1600 FEET

.~--~--~I--------~I

SCALE

SEATTLE WATER DEPARTMENT

LAKE YOUNGS

IMPROVEMENT PROJECT

PERIMETER DIKE BORING

LOCATION PLAN

FIGURE I

DEPTH IN

FEET P-I P- 2

01 SP\ o .... SPT

SAND &

:J ~L

I GRMEL

S~ 3q

3~ q

4S

8 2 t 3

10 -l 37 SILT Y

SAND

12--1 WI

~ ~ GR AVEL 2

14 -l

Ib ~ SI bD b7

H 20 1 bOI S 22 • bO/ 3

2~

2b

2 8

P- 3 P- ~ P- ~ P- b P- 7 P - 8 i--- SPT SP T t c:. .6.'"I!',) & SPT I SP T SPT SPT . .. ... • SPT

SAND & SAND & SAND

SILTY

.... GRAVEL GRAVEL

H • 2q ~ b I Lf +r.g:.\v~·1 18

GRAVEL

~ ;/+ ; SILTY II ~ 12 nb 20 10 '.:1""", 2b

3 / 2

SAND ~ ~ R MINOR ' SILTY q . / q

GRAVEL . ' GRAVE LLY

/' SAND

2 / /,% 8~ 3b

~ I""' 2 ~ CHI I"'I TD :£f" 2 / SILTY 1/ 21+ 7.jGRAVELlY GRAVELLY / SAND 3q

SAND

b 0 r ! SILTY SAND

2 2 ! 12 / LITTLE GRAVEL S7

3~ 3 ~ 83 t SI LT Y 10 1

~7 n SAND

8q

NOTE S :

I. S P T DAT A BLOWS/FT

2. SHAD ED AREAS DEPICT LOOSE.

LIQUEFACTION PR ONE DEPOSITS

3. R = REFUSAL

4. LI QUEFACTION ANALYS I S

BASED ON SPT DATA OF

BORING P-2

SAN D

GRAVEL

SAND

MI NOR

SILT &

GRAV EL

SEAT TLE WATER DEPARTMEN T

L AKE YOUNGS

IMPROVEMENT PROJECT

PERIMETER 80RINGS

GENERALIZED PROFI LE

,IOIJftE 2 A

EB ASCO SERVICES INCORPORATED

DEPTH p-q P-l0 P-II P-12 P-I ~ P-I b

IN FEET

P-14 P-I~

SPT SPT SPT SPT SPT SPT SPT SP T

0, SAND &

SAND & GRAVEL SAND

2 -I ~ I GRAVEL

41 SAND 46 SAND R SAND ~O SAND, Iq SAND GRAVEL

4 ~ & & & TR SILT, & R

GRAVEL GRAVEL GRAVEL GRAVEL MINOR SS

b J 2~ T 10 I~ II 8 0

GRAVEL GRAVEL

4~ 2 1

SILTY SILTY

SILTY ~ SILTY

8-1 4 ~SAND

SILTY SILTY 4 FI SAND SAND 6 SAND

SAND SAND SILTY

4 G:'VEL

12 MINOR 4 MINOR MINOR

MINOR MINOR SAND SILTY

~ GRAVEL GRAVEL 42 , GRAVEL

10.j 7 / GRAVEL 2 ,,', GRAVEL S MINOR 4 VI2, I SAND

6 GRAVEL S q

12 ~ 2~ t S H SS R

SILTY

SAND II H H

14 j 12 -+ & S8 28 -+ S6

GRAVEL

SILTY SAND 24

SAND q2 I~ MINOR

16~ 27.1

& SI LTY GRAVE L

2q GRAVEL SAND & 61 R S1

SI

18 ~

Rt

GRAVEL R

8 R

PEAT WI 4~ R

20~ SILTY SAND

b8

22 J ~4 R

24'j + SILTY 41 SAND

26 • WIGRAVEL

SS SEATTLE WATER DEPARTMENT

10J LAKE YOUNGS

IMPROVEMENT PROJECT

PERIMETER BORINGS

GENERALIZED PROFILE

FIGURE 2 B

EBASCO SERVICES IN CORPORATE D

e

I-

III

1&1 10 Z

II

N

:z:

I- 12 Q..

III

z

0 .1 I

0.2 I

0.3 I

0 .4 0.5 ..

./ ""-- FACTOR OF SAFETY

wI RESPECT TO

LIQUEFACTION

CYCLIC STRESS RATIO

INDUCED BY CLASS I

M7. 0E.Q .

CYCLIC STRENGTH UNDER

M7.0E.Q.

CLASS I E.Q.

LIQUEFACTION POTENTIAL FROM

BORING P-2 PENETRATION DATA

SEATTLE WATER DEPARTMENT

LAKE YOUNGS

IMPROVEMENT PROJECT

CLASS I EARTHQUAKE

LIQUEFACTION POTENTIAL

FIGURE .,

EBAS CO SERVICES IN CORPORATE D

I W W U.

z

N

3:

I a..

W o

I I

FACTOR OF SAFETY

o 0.1 0.2 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0

4: - ..L z

CYCLIC STRENGTH

UNDER M5.6 E.Q.

CYCLI C STRESS

INDUCED BY

M 5.6 E.Q.

z

CLASS n E.G.

LIQUEFACTION POTENTIAL FROM

BORING P-2 PENETRATION DATA

I I I I

ZONE OF POTENTIAL

LIQUEFACTION DUE

TO CLASS n EARTHQUAKE

SEATTLE WATER DEPARTMENT

LAKE YOUNGS

IMPROVEMENT PROJECT

CLASS II EARTHQUAKE

LIQUEFACTION POTENTIAL

FIGURE 4

APPENDIX

BORING LOGS

GRADATIONS

PROPERTY LINE 7

'I

P -6 p-".\ LAKE YOUNGS

. \ RESERVOIR

N

SHADY LAKE

CASCADES

DAM

1'FL---_II ..... 00_--1.y ___ ---l1lJOO FEET

SCALE

SEATTLE _TER DEPMTMENT

LAKE YOUNGS

IMPROVEMENT PROJECT

PERIMETER DIKE lORING LOCATION nAN

Draw; ng 1

KEY TO SOIL SYMBOLS AND TERMS

n_s VUD II TMIS I£'OIT "01 OUtllll" SOILS ""Coaol" TO TIUI TUTUl[ 01 lUll Un:

DUTUIUnOIS AU 'UUAlL' II AceOlDutl IUTI! TME UIHfUQ SOIL CLASSlflt'TIOI SUUI .

ITIIIS DESCRI!1106 COOlITION. COIISISTEJICY MIl KAIIIESS

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WI. SIZE DISTRIBUTION

-cur

-I SIll I: M

:~ ,. ~ ·1 ~ .. _ .

IN » .. » • • • • • •• I' .. ); iii '" ..!!: r .. " .. u u Ii p~ DUooIIC1'D .... LoU....., Drawi ng 2

OA TE DRILLED, 2/4/85 SUMMARY: BORING NO. P-l ELEYATlON, 495.4 YI"I IU.II .. I? .... , ... t. Oil' I.f ,,,. LOC.TIOM 0' 'M'I 10 ••• 0 ."0 loT nUl: "Ill O' OI'H 'Me

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DESCfUPTlON SYMBOL MOISTURE CONSISTENCY «,"

1A 60/ .5 11

SANDY GRAVEL (Fill); gray-brown, fine to coarse, little silt, 17 subangul ar 2A 29

- 25

- 5

- 3X 3 SILTY SAND (Fill); brown, fine

2 to medium, 1 ittle gravel, trace

- 2 charcoal

5 - 4X 2

- 1

5A 1 SILTY SAND (Till); gray, fine to 2 medium, 1 ittle gravel

- 23

- 6A 42

- 1

- 7A 1

10 - 2

8A 20

- 24

- 1

- 9A 3

15 - 15 SAND; gray-brown, fine to coarse, 10 25 1 ittl e gravel, 1 ittl e sil t

- 26

- 21 -n 32

- 17 SILTY SAND (Till); gray, fine to

- 12 60/5" medium, trace gravel

- 1

Boring terminated at depth 20.9' Additional hole (P-1A) drilled 5' north of P-1 to obtain ring

, sample from 3' to 5' depth •

• A. 2~ 'plll-,poon .. tnpl.r

GW

SM

SM

SP

SM

B. '· O.D. thln-•• II.,mpl.r C. 3-1 / . " 0 .0 . II 2-1 / 2- 11"., ... -Att~'a. C - co"aoUutioll, OS - dirac. ''' •• r, O. 3-112- 0 .0 . • pllt barra' .. ",pia, X. ',mpla not raCO.lrad Q - •• aba, T - tn..Ia., P - Per.,.blllt., LAKE YOUNGS PERIMETER DI KE

King County, Washington

___________________ f~Q~r~E~B~AS CO Services, Inc.

~ Converse Consultants ~n-:~";':·~~~~":rtng moist very ~ 95 . dense

2/28/85

SL F

wet loose f-

~ 90 moist dense

485 =-'

I:-wet very dense b,-' 480 moist very dense p-' 475

Project No.

84- 5119-1 2

Drawing No.

DATE DR'LLED, 2/5/85 SUMMARY: BORING NO. P-2 ELEVAnON, 495.2

'U"U"4CI COIO'TtOl' IA T ,If'" A' OTltl' "OtA'flOI' ... o.n c .... o •• , ""' lOCUIO_ In. TOIl ........ 0. Of' " •• . Til' OATIl ••• , •• TI. "" 1 .... UrlC""O_ O. aCTUAL COIO IlIO"

'"COU""'O.

DESCAIPnON SYM.OL MOISTURE

GRAVELLY SAND (Fill); brown, fi ne SW moi st

- to coarse, trace si lt

1A 21

- 18 grades finer with less gravel

2A 7 2/ 28/85

6 SL

6 SAND (Fi ll) ; brown, fine to SP wet 5 - 3X 5 medium, trace silt, trace gravel

- 4

4B push

- 0 SA 1 1 ittl e gravel

2 2" diameter piece of bark at g '

6X 3 10 - 1

- 1 _ 7 X

- 6 .

- 3 8X 1

9A 11

- 17," SAND ; gray, medium to coarse, SP wet

1~ 1 ittl e gravel, trace silt

10 ~~ .

- 13

II 36

20 - 15· 12 60n" in terminated at de th 21.3 Bar g p Additional hole (P-2A) drilled 9' north of P-2 to obtain ring samples at 4'r.f,j·' •• ",B:.oJA' .... ,~d 12' -14' depths.

8. 3" 0 .0 . thln-•• II umpl., C. 3·' / 4" 0 .0 . .I 2 -1 / 2" Un., •• A - AU.n.-to. C - con,oIldaUOIt, DS - dirK' ,b"r.

D. 3-1 / 2" 0 .0 . • pllt bl",1 nmpl.r X . •• mple not 'lco"lrad 0 ..... ml, T - 'Mlilal, P - P.' ..... bllll'

CONSISTENCY

dense medi urn dense loose dense very dense

Project No.

l-

I-

I- I-

I- I-

I-l-

I-l- I-

I- I- 475

LAKE YOU NGS PERI METER DIKE

King County, Washington for EBASCO Servi ces, Inc.

84-S119-12

II

1A 14

- 18

- 10

2A 18

- 13

5 - 3X 3

- 1 -_ 4B push

5X 1/18 '

10 - 6B push G 23.4

- 1

- 7X 1

- 1 . 8B push G 24 . 8

15 - 9A 9

- 13

- 10 17

- 17 -

- 17

11 20 - 27

• A. 2" Iplll-,poon •• ",ple, SUMMARY: BORING NO. P-3 ELEVATlOH, 495.3 '.11 IU •• "., ""L,II Oil'" AT Till LOC.TIOM 0' T." 101'110 ".0 &, , .. I fllIll 0' '"'LUll e;

.......... ' .. Cl COIIOI'IO., M"" II,nll AT 0' .... LOCATIO •••• o.on <: ..... QI AT ''''f LOCATlOIl

•• T. '". ' ...... 01 0' "" • . 'M' 'ATA '.IU.TIO 'I" I,", .. .,'CI.TIO" 0' ACTUA" eo .. CIITlO ••

DESC'UPTlON SY"BOL MOISTURE CONSISTENCY

GRAVEllY SAND (Fill); brown, fine SW moist dense to coarse, trace silt

SAND (Fill); brown, fine to SP wet . :g loose medium trace to some si lt, trace gravel 2/28/85 very loose

SAND; gray-brown, fine to medium SP wet dense thin layers of gray-brown silt, trace gravel

Boring terminated at depth 20.0'

8 . 3" 0 .0 . thln-waU .. mpl.r C. 3-' / 4" 0 .0 . 1II 2- 11 2" lin., .... A .. Atterb.ra. C .. COftIOUdatlofl, OS .. dlract ahear, O. 3-, 12" 0 .0 . Ipllt barral .. mpl.r X. ""'pl. not ,.co •• rad G .. gr" ml, T .. tn..lel, P .. p.r .. ublUty

Project No.

l-

I-

I-

I-

I-

I-

I- I-

LAKE YO UNGS PE RIME TER DI KE

King County, Washington for EBASCO Services . In c .

84- 5119-12

DATE DRILLED, 2! 5/ 85

- 15 lA 22

- 17

2A 7 5 - 4

. 2 3A 2

I

4B push

5X 2

10 - 2

6B pus h

- 2 7A 10

- 36 8A 60

- 9A 43

.. A. 2- .pllt-spoon .ampl., SUMMARY: BORING NO. P-4 ELEVATION , 495 .2

, .. , • • u ..... , .. ". ~ ••• 0011..' .' 'OI. LO c.aT lO" 0 ' , .,,' . 0 " . 0 • • 0 AT T OI ' " ., 0 1' 0"\.10.1. " 'I,I" \I., .. C I C O.C, Tl O., ."T 0'" " AT 0'01" LO C AT IO.' •• 0 ,la, C .... . OI AT lIOII , LOClotl O,"

. , TlO T il. "A •• 401 0' 1'11'1. TOI l OIlT . " ••••• T lO I .... '. "L'.'C""O. O' ACTUA L c o.on,o ll ' •• cou. t .. , o.

DESCRIPTION SY"'OL MOISTURE CONSISTENCY

SAND (F ill ) ; gray-b rown, fin e to SW moi st dense coarse , some gravel

2/ 28111 wet medi um dense

SAND (Fi l l); brown, fi ne t o SP wet very medium, t race silt , t race gravel 1 Dose roots, organ ics , 1 it tl e s ilt

SAND; gray , medi um to coa rse, SP wet very 1 i ttl e gravel dense t::

SILTY SAND (Till ) ; gray, fi ne to SM moist very medi um, trace gravel dense

Bori ng t ermi nated at dept h 18.5

B. 3- 0 .0 . t h'n- •• II ,,",pIe, C. 3- 1 / " " 0 .0 . • 2-1 / 2 "' ,In., .e A -Att,rbe, .. C " con.OIIdatlon, DS " dlract ahar, o . 3 - 1 / 2 - 0 .0 . split barral ,,",pl., X • •• mp~ nOI r,cov,rad Q .. .,ain ..... T .. trte."I. P .. par."bllll, Project No.

-I ' l-

I-l- 490 l-

I-

I-

I-

I- I-

I- I- 480 l- I-

I-

LAKE YO UNG S PERIMETER DIKE

Ki ng County, Washingt on for EBA SCO Serv ices , Inc.

84- 5119-12

Orawing No.

DAT E DRILLED, 2/5/85

o

- 11 _ lA 11

- 18

_ 2A 7

- 5 5

3 3X 1/1 2 '

- 4B push G 14 .2

- 3 _ 5A 1

- 1 10

_ 6X 1

- 1

7B push G 29 .0

- 5 _ 8A 4

- 8 15

- 6 _ 9A 16

_ 10

I ~~

• A. 2" 'plll-,poon ""'P~'

SUMMARY: BORING NO. P-5 £LEVAT'D. , 495 . 0

'Mil . U .... ., " ' PL I.' OILY AT T MI LO C ATI O_ 0' TMII 10"'.0 " "' AT T" I T' " ' 0 ' .aI U . I .C;

I"" ,,,," '''CI CO"OITlO" • • , .",.. AT O'M'I LOCA'IO" ....... , C •• 'GI ., 'M', Loe",..o_ wnll ' 01 . ' .... .. 01 O' TI.,. ' "' ,AU ....... "0 .. ,," "LI" CU ION 0 ' AC TUAl CO II O.,. IO".

DESCRIPTION SY".OL MOISTURE CONSISTENCY

SAND (Fi ll) ; gray-b rown, fin e to SW moist medi um coarse, litt l e si l t , litt l e gravel SM dense t race charcoal, till-like chun ks

2/28/85 sz.

SAND (All uvi um); gray-brown, fi ne SP wet very to med i um, l i t t l e sil t, some gravel loose grades cleaner to t race si l t SP grades f iner to some silt, 1 i t t l e gravel, t race organ i cs SP

SAND ; gray-brown, f ine to med i um , SP mo ist medi um trace gravel , t race si l t dense

., dense gray

Bo ring te rm i nated at depth 19.5'

1 . 3" 0 .0 . t hin- WIn •• mpl" C. 3-1 / .... 0 ,0 . • 2-1 / 2'" IM.r · ·A -AUeMrg. C - cona~Uoft. DS" direct s"'" 0 . 3 - 1 / 2 - 0 .0 . spli t barrel .,mpl'r X . •• mpla not recoy.rad Q - ..... ab., T - trlllalllt. P - P.' .... IIIUt)' •

Project No.

LAKE YOUNG S PERIMETER DIKE

King County, Washington for EBASCO Services, Inc.

84-5119- 12

Drawing No.

DUE ORILLEO, 2/6/85 SUMMARY: BORING NO. P- 6 ELEYAnON, 495.9 T " lt lue.AII 'I ....... "" • • o ln.'!' ., 'M' ,"OC A,..O. O. TIll ' 10.,.0 • • 0 .. ,. 1'"1 "'11 ' D. OI"~~ '.G

IU" U" "CI CO • • 'TlO •••• ,. 01",.1t . , 0"1' " ,-OCA' IO • • •• 0 •• , c .. . . Ot . T , .. , ' LOC ATIO.

W'T " ,II, ..... .. 01 0' fill' . 'I' ll' 0 "' ........ '.0 'I ... ' ."LlrIC. TIO_ 0' AC TU" .. COllll lftOIl • •• C;O UIITt .. O.

DES CAIPnON SYMeOL MOISTURE CONSISTENCY

SAND AND GRAVEL (Road Su rfacing) GW

21 GRAVELLY SAND (Fi ll ) ; mottl ed brown SW _ lA 25 & gray, f i ne t o coarse , l ittl e sil t 21 ·

· 2A 11 grades f ine r wi t h i ncreas i ng silt , 9 and 1 ess gravel

- SILTY SAND; brown , fine to coarse, SM

- 8 1 ittl e gravel

_ 3A 5 4 -o 4B push 10 -

0 SILTY SAND (All uv ium); brown, fin e SM to coa rse , trace gravel, trace

· 5X 1/24 ' G 20.9 organi cs

· 6X push , G 43 .2 15 -

6X push grades t o f ine

6X push - SILTY SAND (Till ); gray, f i ne to SM 30 medium, t race coar se sa nd and 7A 39

0 62 gravel

- 8A 23

Bo rlng t erml nated at dept h 21 .0 , Add it ional hole (P-6A) drill ed 8' south of P-6 to obta i n ring samp les at 10.5 ' to 12.5' , and 14' t o 16' depths •

• A. 2" .pln·,poon .ampler

• . , " 0 .0 . ,hln-wall umpler C. 3- 1/ 4" 0 .0 . II 2- 1/ 2" ,1ft" ··A -Attan..rg. C - consolidation. DS _ dlrlct eh •• r.

O. 3 - 1 12 " 0 .0 . • pllt barra' " "'pl., X. "Mpl. not rl eo".rad 0 - pain "" , T - triaxial, P - " rat.,blUlr moi st dense mo is t dense very medi um moi st dense 2/ 28/ 85

\l wet wet very l oose very very moi st dense

Project No.

I-f.

f.

f.

I- I- I-l-l- I-l-

I-

I-

LAK E YOUNGS PERIMETER DIKE

King County , Washi ngton for EBASCO Services . Inc .

84-5119-12

Drawing No.

DATE DRILLED, 2/ 6/85

lA 9

- 5

5 - 2A 5 5 .

30 3A 60/5 ' -

- 4A ~~ 10

• A. 2~ ,plll-,poon .. ",pier

SUMMARY: BORING NO. P-7 ELEVATION, 496.1

" ..... u .......... "' •• OMU aT ,. ... ," OC.TlOM 01' , ... , 1011.0 •• 0 AT '"' T'.' 01' .II/,.lIM '

IU',,,I'.CI COMOITIO •••• ,. 0'."1 ., OTlI" "oeaTtO •••• 0 .n C .... o •• , tM'f LOC.flO.

w,,, .. ,ot, "."IUt. 0' " ••• Till .AtA ."1.1'10 'I" "."LI,.'CATIO. O' ACTUAL C:OIIOlt,O", I.COu.n.OIO.

DESCRIPTION SYMBOL MOISTURE CONSISTENCY

SAND AND GRAVEL (Road Surfacing) GW

SILTY SAND (Till Fill?); gray, fi ne SM moist medium to medium, trace gravel, trace dense roots and organics /28/8

5l grades cl eaner, coarser brown and gray, little silt wet

SILTY SAND (Weath. Till); gray- SM wet very brown, f ine to coarse, with gravel den se

Boring terminated at depth 10.5'

B. 3· 0 .0 . • tl ln-•• llumpl., C. 3-' / 4" 0 .0 . • 2-1 / 2·'ln" ··A -AttwMrs. C - COftloMdlitkm. DS - .... ect ~".

D. 3-' 12- 0 .0 . split birr.' •• mpl., X. ""'pl. "ot ',co".r,d Q - ... _ aaze, T - tn. ..... p - P,,."blllt, Project No.

f-f-f-f-f-f-f-f-f-f-f-

LAKE YOUNGS PERIMETER DIKE

King County, Washington for EBASCO Serv ices , Inc.

84-5119-12

DrawIng No.

DUE OR'LLEO, 2/6/85

. 7 l A 9

- 9

5 - 2X 15

. 11

- 3X 5

- 4

- 4A 18

18 10

- 5A 15

- 6A 25

.. A. 2" .plll-.poon •• mpl., SUMMARY: BORING NO. P-8 nOVATION , 495.3

.U • • UII' ''CI co.ooTlOII, • • U 01" 111 .. , OTII ' " "DC.TlOII' •• 0 II., C'" IIIOf A' Till ' LOC ATI O.

WIT II T"I , • • , &O( O' TI • • . T" I OA' .. ... .. 1 11 ' .0 I . " ,'."\.1"1 C A'IOII 0' AC TUAL CO.OllIO", IIlC:OUII TI.'D.

DESCAIPnON SYMBOL MOISTURE CONSISTENCY

SAND AND GRAVEL (Road Surfac inq) GW

SILTY SAND (F ill ?) ; mott l ed gray & SM moi st medium brown , f ine to coa rse, some gravel dense

2/ 28/ 85 5Z...

wet l oose

SILTY SAND (Ti ll ); gray-brown, SM very dense f i ne to medium, littl e gravel moist

Bo r ing t erminated at depth 15.5'

B. 3" 0 .0 . t hln- .,II .. mpl" C. 3- 1' '' - O.D. JI 2-1 / 2-1.,.., . ". - A.tt~.r .. C - co",oUdaUon. o s _ dl'~t eMlar, D. 3-' 12 " 0 .0 . • pllt blr, ,' .. mpl" X. ""'pl. not 'Ico • • r,d Q - .... In "" , T - tn. . .... p - p.rm.,bllll)'

EAkt 9UUNGg PtKiMt itK bikt Project No.

f-f-f-f-f-f-f-f-f-f-f-f-f-f-f-f-

King County, Washington f or EBASCO Servi ces , In c.

84- 5119-12

@ Converse Consultants Gootechnlcal Englneertng Ind Applt.d SClene ..

D.TE DRILLED, 2/6/85

lA

5 - 2A

- 3A ·4X

10 - 5A

- 6A

15 - 7A

8A

20 - 9A

60/5 '

- 101 60/5'

SUMMARY: BORING NO. P-9 ELEv.nON, 495.9 T'", .u ..... Y ...... LI •• OILT "' 'II. LOCATIOII 0' 1'1111 1011110 4.0 AT Ttl. ,.tln 0' OIl'LUIIC;

au.aU"ACt COII'ITI •• ' •• , 0''',., AT 0'".1 LOCATI •• ' ... , ... , CIII ..... AT , •• , LOCATIO_

."M 'N ......... 0101' TI.' . TlII' •• ,. ""1.11":0 II " ..... I..,II:.TIO. 0' ACTUAl COIIOITIOII'

'.COUII'IIII".

DESCRIPTION SYMBOL MOISTURE CONSISTENCY

SAND AND GRAVEL (Road Surfacing)

GRAVELLY SAND (Fill); brown, fine to coarse, 1 ittl e sil t grades coarser with increasing gravel

SANOY GRAVEL; gray-brown, trace silt

1 ittle silt

GW

SW

GW

:sAND ; mottled orange & gray, f i ne SW to coarse, some gravel, 1 ittl e silt t race organ i c s

SILTY SAND (Till); gray, fine to medium, trace gravel

SM

moist

~/28/85 Sl...

wet wet very moist dense medium dense loose medium dense very dense moi st L: very dense

• • . 2- •• 111-0.00 ...... ,.' ~or1ng termlnateu aL UepLII Lt.'! •• t., .v.

Impervlou •••• 1 1 . 3- D.O. thin-wail .. mpl.r C. 3-1 / 4· 0 .0 . • 2-1 / 2"11"" •• ,. -Att.~r .. C - COftlolldeUon., OS _ dlrKt ...... r.

D. 3-' 12- 0 .0 . Ipllt barral .. mpl., X. "mple not r,co".rad G - .,.an .u., T - trlaallli. P - p.r ••• bllll, pl. lome Ie' lip

ProJect No.

f-f-f-f- 480

LAKE YOUNGS PERIMETER DI KE

King County, Washington for EBASCO Serv i ces, Inc.

84-5119-12

DrawIng No.

1 1

DATE DRILLED, 2/6/85

· 16 1A 14 - 14 ·

5 ~ 2A 6

3B pusr

4A 2

10 - 5B pust

_ 6A 4 ,

- 7

- 7B pusr

15 -

0 6 _ 8A 7 0 21 E

_ 9A c 0 6C

15 - 10 31 20

~4

SUMMARY: BORING NO. P-IO ELEVATION, 495.5

fl"l .1,1 .... , .""\.Ie. OIlU AT Tltl LOCATION O' Til" 1011110 ... NO AT 'MI "III 0' Da,u",,, 1", •• UII,"el COIICIIT'O"" ... , 0 .. ". AT 01'11.111 LOCATIO., •• 0 •• " CMA"OI .T 'M'f LOC."OIl

.". T"I ...... 01 0' TI., . '"' ''''A .11.1'."0 II .. ' •• "\.I"C."OII 0' ACTUIoL COllonIO", ,IICOUII' .. IO .

DESCRIPTlON SYMBOL MOISTURE CONSISTENCY

SAND AND GRAVEL_(Road Surfacina) GW moist ~ dense

SAND (Fill); brown, fine to coarse, SW moist medium some gravel, trace organics, little dense silt

:z 2/28/85 wet loose gray-brown, silty SM

SILTY SAND (Alluvium); dark brown, SM wet loose fine to medium, little gravel, tl'ace root s, organics

SILTY SAND (Weath. Till) ; gray , SM very dense fine to coarse, little gravel moist

SILTY SAND (Till); gray, fine to SM moist very coarse, trace gravel dense

Boring termlnated at depth 21.0' Additional hole (P-10A) drilled 7' south of P-10 to obtain ring sample at 8' to 10', and 10' to 12' depths •

• A. 2- .plll-,poon •• mpl., I . 3" 0 .0 . thin-wIll .. mpl.r C. 3-1 / 4" 0 .0 . • 2-1 / 2"'1"., •• A -AH....,., ... C _ cOflt,oIlct.tlOft. DS _ cPrec:t ..... , .

0 . 3-1 / 2 " O.D . • pllt barr.' umpl., X. umpl, "ot flCOWlr,d Q - grain -'z., T - triaxial, P" parm •• blllty

Project No.

I-

I-

I-

I- I-

I-

I- I- I-

I- I- I-

LAKE YO UN GS PERIMETER DIKE

King Cou nty, Washington fo r EBASCO Servi ces , Inc .

84-5119-12

Drawing No.

47 5 onE DRILLED, 2/7 / 85 SUMMARY: BORING NO. P-ll ELEVATION, 495.3 1'IU' . ....... . " ...... u •• 0111.' .t "I' ," OC A" IOII O. , ... "1'11 0 ... , 10" " ... TI •• 0 ' 'l'U. llle ..... . u.r AC' COIIOITIOI •• " ., 1 " "111 A' 0'. '" LOC ATIO'" •• , . '" t ll .. . en AT Til l ' LOCIITlO Il II . T II Til l .. . .... 0. 0 ' '1111 . f ll' OA,& .. . .... T •• 'I •• '.'Url CA,.. O. 0' .C. 'I,I& L COII O,TlO.'

DESCRIPTION sy .. eOL IIOISTURE CONSISTENCY

SAND AND GRAVEL (Road Surfaci ng) GW

17 SILTY SAND (Fill) ; brown, f i ne to SM sl ig ht l y dense

- lA 20 coa rse, 1 itt l e t o. some gravel mo i st 21 f-

P/ 21 / 8~ 14 wet \l med i urn f-

- 2A 9 dense f-4 f-

- 3B push G 18.4 occas ional organics (bark, wood very chi ps ) loose f-f-

1 f-4X 1 f-- 1 10 5B push f-gray f-23 SILTY SAND (Weath. Till ); mottl ed SM moi st dense t o f-- 6A 22 , gray and t an, f i ne t o coarse, very f-21 trace gravel dense f-

25 f-

- 7A 32

60 15 f-

- ~ 20

- 8A 16

Bo ring t erminat ed at dept h 18.0' --

• A. 2- 'pllt-,poon ,.",pla, 8 . 3- 0 .0 . tlllfl-•• " "l'I'Ipl. r C. 3 - 1 / 4" 0 .0 . I: 2- 1/ 2" ..... ' •• A -Atterberg. C '" cOMoIkIaUon. DS", direct abe."

D. 3- 1/ 2 - 0 .0 . 'pllt ba, r.' ""'pl. , X. ""'p" ftot reeo".,.d Q ..... ..... T ... tria ..... po ... "nn_.bllll, LAKE YOUNGS PERIMETER DIKE

King County, Washington f or EBASCO Services, Inc .

Project No.

84-5119- 12

DrawIng No.

DATE DRILLED, 2/7 /85 SUMMARY: BORING NO. P-12 ELEVATION, 494.9

, ..... ., ..... , ..... 6.1 •• OMU AT ntl Loca"o_ 0' 'M.I "" ....... AT T"I T.II. 0' '"ILlI" e:

IU.'UI'ACI COI.'TlO ..... , 0.",. AT 0"1'111 "OC .. "O ..... 0 .'" e .... ol AT lMI, LOC""OIl

""" ,,,. ' ...... 0. 0' Ttili . 'M' •• ,& ....... TlO 1I.t. 1'."\.I"C .. TlO_ 0' &Cl"AL COIIO,,,O .. , .lIeo".'.II.O.

DESCRIPTION SYM.OL MOISTURE CONSISTENCY

SAND AND GRAVEL (Road Surfacing) GW dense

- lA 25 SILTY SAND (Fill); gray-brown, SM slightly dense

· 21 fine to coarse, little to some mOi~~ gravel 2/28/8, 10 wet medi um _ 2A 8 dense 3 · SJLTY SAND; (Fill); mottled gray, SM wet loose

36 push brown, & tan, fine to coarse, trace to li tt le gravel, occasional

- charcoa l

4A 1

10 - 5X 4

66 pust 24 SILTY SAND; (Fill); gray, fin e to SM very dense

- 7A 24 coarse, little gravel, occasional moi st

· 13 organ ic pocket

· 11 _ 8A 11 medium

· 4 dens e 15

- 5

- 4 _ 9X

5 loose

4 PEAT; dark brown, slightly fibrous Pt very medium 10 9 7 moist stiff

(Cont i nued)

• A. 2 - Iplil-ipoon ""'1"1"

B. 3" 0 .0 . thln-w." .. ",pi" C. 3-1 / 4· 0 .0 . x 2-1 / 2· ..... ' •• It -Att~ C - c-.oIkI,Uoft,. DS - direct D. 3-1 / 2" O.D. Ipllt blrre' .,,,,ple, X. "mp~ not r'co".red 0 - ....... tk., T - tN .. ~I. P - p.r ••• blllt, Projeci No.

-I.

"r-,,"r-f-f-f-f-f-f-f-f-f-

- 475

LAKE YOUNGS PERIMETER DI KE

Ki ng County, Washington f or EBASCO Services . In c .

84- 5119-12

~ Converse Consultants :n,,:=~!:~~~,=~ng

DATE DRILLED, 2/ 7/85

10 6

11 6

- 16

- IV 24

27 - 25 -

131 ~ 23

SUMMARY: BORING NO. P-12 ELEVA.TION:

1'." .It ..... , ... ·PLl •• O.U AT T., LOCATIOtt 0' 'M'I ~J1.~~F .. : 1, Til. TIM' 0' DI'LL'I e;

IU.,U'."'''' COIOITlO., ."T 0'"'' AT O'ot'l LOCATIO.' ........ , e"",ol "T , ••• LOCatIO" WITII ,16' " ..... "01 O' 1".'. T.' 'AT .. ""'.1t'10 II " I'.I'LI'. ,..1,"0_ D • . U:TU"L co"on,o", ."COIt'''''''.

DESCRIPTION SYM.OL MOISTURE CONSISTENCY

PEAT (Cont.) Pt SILTY SAND; gray-brown, fine to SM very medi um medium, trace gravel, occ. charcoal moist dense

SILTY SAND (Weath. Till); mottled SM moist very bl:own and gray, ftne to coarse, dense little gravel c.;

Boring terminated at depth 26.5' f-f-f-

470 , f-f-f-r r r r f-

• A. 2" .pl"~.poon •• mpl., f, :;::::::' ... 1 8 . 3" 0 .0 . t"lft~ •• 1I .. mpl.r C. 3·1 / 4" 0.0 • • 2·1 / 2" ..... ' ... A. -Attar1Mrg. C - conaoHdlitiOfto DS - INrI,.t ,h •• " 0 . 3-1 / 2" 0 .0 . • pllt blrrl'umpl,r X ...... pl. ftot raco".,.ct Q - wain .u., T - trta ..... p. "r""'blllly

LAKE YOU NGS PERIMETER DIKE

King County, Washington for EBASCO Services , Inc.

~ Converse Consultants Geolechnlcll Engl_rtng Ind Applied Selin ...

(] piezometer tip

Project No.

84-5119-12

DrawIng No.

14 (Cont.)

OA" 00ILLOO,2/7 185

17 -_ lA 41 34/3 '

5 - 17 _ 2A 14

- 3 . 4 _ 3C

4A 1

- 3

2 10 5A 2

- 3

6A 24

- 34

- 19 15 _ 7A 29

_ 8A 27

.. A. 2- .plll-spoon •• rnpler

SUMMARY: BORING NO.P-13 ELEVATION, 495.5

" .... I "' ••• ' " I.HLlII 01110.1' , .. f ,. .... LOCATIOII 0' TMI' 101'1' •• 0 AT Till " ... O' .1'LUlle;

IU"""ilCI COII"TlO., •• , 011'.1 AT 01'." LOCIl1'l0.' •• 0 .... ell •• " .T 'M" Loe .. "o_

." .. 1'1" " ....... 0' 1'1.,. '"' OAU. ' ••••• T.O ' I .. ' •• 'LI" CATtOIl 0' ACTUAL COIIOITIO"

'"COUI" "O.

SYMBOL MOISTURE CONSISTENCY

SAND AND GRAVEL (Road Surfacing) GW

SILTY SAND (Fill); brown-gray, SM moist very little to some gravel dense

2/28/~ \7 t-sIrTY SAND ; (Fi ll ); gray-brown, SM very loose fine to coarse, lit t le gravel , moist occasional organics very with dark brown organic silty sand wet l oose 1 ayers

SILTY SAND (Unweath. Till); gray- SM moist very brown, fine to coa rse, trace gravel dense with fine to medium sand len ses

SAND; brown, fine to medium, trace SPI wet dense gravel, occasional till chunks SM

Bor ing terminated at depth 19.0'

8 . 3· O.D. thin-Will Slrnpl,r C. 3-1 ' .. ... O.D. a 2-1 / 2-1." ··A -AHertMro. C - COftloUclaUoft, DS - -...ct ~.,.

0 . 3-1 / 2- 0 .0 . Ipllt bl"" "",pi" X ...... p .. not '.co .... r.d G - ..... aka, t - tn. .... , p - ",....bl ... ' r", :;:::~::I , .. , o plezom, t., tip

Project No.

t-t-r t-

LAKE YOUNGS PERIMETER DIKE

King County, Washington for EBASCO Serv ices, Inc.

84-5119-12

~ Converse Consultants ~n":=::~~~~=~nv Drawing No.

DUE DRILLED, 2/7 -8/85

o lA 14 50 -

12 -

- 2A 5

- 34

- 3C 2

- 2

- 2

- 4A 1 - 2 -

1 -

- 5X 1

4 10

- 6A

16 - 23 -

- 7 A 12 -

15 -

- 14

8A 13 1R

• A. , .. 'pllt-spoon umpl., SUMMARY: BORING NO. P-14 ELEVATION, 494.9

"It •• " •• "., """LlI. O.~, AT Till LOC"TIOII 01' 1' •• ' 101'1Ier. ... O"T Till Till' 0' O'"LLIIU:;

.UII\HI'ACI COIIDlTIO" II'" 0' ....... T 0'''.1 LOCATION' .11. II", C"".OI At "~"' LOCATION WITII nil ' ..... 0. 0' Till' . '"' 0., ••••••• '.0 I' .. "."UI'I C."'OIl 0' AC:TUAL eOIlOI"O'"

'.COUIII''''O.

DESCRIPTION SY"'Ol MOISTURE CONSISTENCY

SAND AND GRAVEL (Road Surfacing) GW

SILTY SAND (Fill); gray and brown, SM moist very fine to coarse, trace gravel, occ. dense organic pocket

SILTY SAND; dark brown, organic, SM wet very fine to coarse, trace grave I, occ. ::z loose sandy silt layer 2/28/ 85

SILTY SAND (Till); gray, fine to SM moist dense coarse, trace to I ittl e gravel, with fine sand lense

SAND; gray & brown, fin e to coarse, SP wet dense trace silt and gravel, occasional till chunk

Boring terminated at depth 17.0' e . 3· O.D. ttlln-WIII .. mpl.r C . 3-1 / 4" O.D. a 2-1 / 2" nft., "." -AttlMHrg, C" c ... o8d.Uoft., DS" dffecl D. '-1 / 2" 0 .0 . • pllt blrret .. mp~r X. ""'p" ftot "co •• r.d Q - If. we, T - trilla .... p .. "r .... blllty

Project No.

f-f-f-f-f-

LAK E YOUNGS PERIMETER DIKE

King County, Washington f or EBASCO Servi ces , Inc.

84- 5119-12

~ Converse Consultants !-:=~.~~'!';=rtna Drawing No.

DUE DR'LLED, 2/ 8/ 85

· 16 _ 1A 10

2A n 55

5 -

· 3 _ 3C 2

· 1

1/12' 4A 1

- 10 10

SA 17

6A 26

28 15

7A 31 60/5"

• A. 2" .pllt·.poon .. ",pie, SUMMARY: BORING NO. P-15 ELEVATION, 495.3

'1I •• II.'Ae. COIID.TKJ •• "'" .,.'.11 AT on'l. "OCl"O.' ".0 ... , C".1I01 A' nil' LOColTlOtf

• ,TII Till ' ...... 01 0' nil • . T., IIAT" ' ••••• ,.0 " " II.'LI'" C.flOII 0'- .. CT ..... l COllonIO.' '"COlllln .. :O.

CONSISTENCY DESCRIPTION SYM.OL MOISTURE

SAND AND GRAVEL (Road Surfacing) GW dense

SILTY GRAVEllY SAND (Fill); gray- SM very medi urn brown, fine to coarse moist dense

2/28/~ wet very dense

I-

SILTY SAND; dark brown, fi ne to SM wet very l-coarse, little gravel loos e I-l-l- I-

SILT All) SAND ; red-brown, fine to ML/ wet very I-coarse sand SM loose I-

SILTY SAND (Unweath. Till); gray- SM moist very I-brown, fine to coarse, trace to dense 1 ittl e gravel

1 ess silty lense at depth 13' r r r

Boring terminated at depth 16.4' l- I-e . 3- O.D. thln-""" .. ",pl., C. 3-1 / 4 " 0.0 . .I 2-1 / 2"un.r •• ", -AtteJb.,a. C - con,oUd,tlOfl, DS _ dirK D. 3- 1 12 " 0 .0 . 'pllt b."., .. "'pier X. ""'pl. not recovered G - • ..,. liz., T - ...... lel, P - iM,,,, •• blllty

LAK E YOUNGS PERIMETER DI KE

King County, Was hi ngton f or EBASCO Serv i ces , Inc.

Project No.

84-5119-12

-CLAY '1'" SILT '/'" SAND '1: GRAVR :1

'" FINE , I-MEOIUM ,1 COARSE FINE , I-COARSE ,

SIEVE SIZE NUMBER 270 200 140 100 60 40 20 10 4 *" *" I" I lh" 2" 3"

100 ~'l"ll:" I}' T;'I' 'TI Trm~'J: l-r' T'T' nil!' T' j:l:-n\Ti 7:1;1i['1 ITlr' J:' :C'~I~~' ''''''''''mr11 '''p1Tm' '1; nl11

, I; ' .'. .', I ,·, ' I ! 1 ,I , ; I: :; , I I , I I l ' 1'1 I :-- " I i I I Ll I 'I 1 : 1 ' . I ·1 ' 1 I ' ! ", '; 1 I' 'I' ! 'I I ~ I " ~ , I ~' ,I It I U I ~ - _·-t ,':-' :- I -r-t-t, ' ,---I : -~- ._-' -- --:-h ';--1 -1;- /"'<-':_-1- '--' 1 f-',711 I t : i:l ' iii Ii:: I" I ! 1 'I ' i : : 1 i I ! I 1'1 ' I ' II ": , '; : '1' 1 I I ' ~ 'I i :1 ' w . I ' L "I " I, II' ~ I "I I' I / I ' ~ ; :/./. Ilf- I ! ' '4' , ! iI: 'm' ' h > 80 - -rt-.;-, .-' , ,_._-.L.._ ' ;....-- -1 --- '.'- '- ----'----t- 'I'~ I'...l" --' - __ ._. _L_ .. _ ' ~-'--II-+fr-- ' ' L , '--'-H w I I ' . , ' ; I ' I ' " " I r ' 'f I ' I ' , I , ' ' I 1' 1 ' ,I' 1 I I

~ ' _- ~ ..L'-Li. ! I:J~~ __ ~ __ .J_: ___ tJ~_i L.L ~ .iIJ I I I l_~_r I ~ iii! : 1: 11 , ·1 ' o z ~ 60 - - ;'-! "':-+ --r-'j-ri I ' '----1-.. - :---' ''-I-L'rt!: r: l - 1. ': .. ..:. .. 'I-rttttt-'--I----: --or', Ll ' - I ' -I i 'm' - ,- , til ' 1 I 1 ' I r I I! I, I I 1 I . , I ' 1 I' I / 1 I" I w l ' I' I I I , ' I , I :" I : ' .' ! , I : " t ! ' • • I ' I I ' '! I ' 1 I I t j ,~ 0:: ' J' , r: ! . I I -:, " Ii' I :, : [ I . I I '" ' , , , : I ' ! I ~ --;- I"~--:-r-'I I I ~I::' ~i--~-··-· I .. - I '-i-c l-i- I -i·· - I I-~d-H--~ .. --~·T---I ---.. -·Ttl--_rlt I~"I u : ; , ; i I I' Wi I 1 . ' I I ',' 'I: : II :: ,: ! I : II : I ; : : II; . ' t 4+' I I ; , Z '.....::.J I , [JI I ' " / 11* ' , I ' rl+I ' t ~ ' ...L( ' ~ ' I~ ' ' ~ 40 - :. ! J~+~-( I ' I-[:--;~--:--~~: ' : ,-- :'/ --1:-' --+11 I: ,- :-- , --.-+-- --, :; I: \..-, - I ' 1 ~ i, i ; : '1 , . ~ -' .' I : : I: :1' II III ' r :'1 I i I[ 'I 1111 : I : j":! ; , ' Il l ! ' ,: I \ '

. I .. , ' ,'; li ' J....., i , ' t-l ' "" .J.j-J~J

U - r t j I.. ... I I I : ; ,I / : I I " .' . tI l! I I I · ;

0:: . . I" .: I i': : " , .. , ., i yl ' I!', I I ! ::, 1 I '[ [' I '. ; i 'I a.. ----...--- : ~ -.-~.--- --1 ITHL_t_~ -*--1--,..-- -t- t • I t- 1--. .-W ; I I . i'; . i " . 'I ''i' , r ": 'r ' i' ' i I ' ft· ,- i' '. , I ' i .. I .. ! : I , I ' [ ,: " , ' ' : . I ii , II I ' ! i : I :. I · · · · . " ' , . I. , ,. .. , I ' I I II ' , I I I I ' I , , . I" I" .. I' I I i I I , , : I ' I" , I , j I . . :' , I I ,. . ..... . 0 ' ' . . , ... , I .1,., .. , I "" . , . , . I ,'. .

.005 .01 .05 0.1 05 10 5.0 10.0 50.0

• P- 3, 5-6 , depth 9'-11'

• P- 3, 5-8, dep t h 1 2~ ' -14~ '

PARTICLE DIAMETER IN MILLIMETERS

GRAIN-SIZE DISTRIBUTION CHART

Projecl No.

84- 5119-1 2

LAKE YO UNGS PERIMETE R DIKE

King County, Was hington for EBASCO Ser vices , In c .

----==-----------------.:..------~----- Drawing No.

@ Converse Consultants Geotechnical Englne.rlng .nd Applied Sclenc •• 18

-CLAY _lot: SILT _lot: SAND -I: GRAVEl: :1 ot: FINE .I-MEDIUM _I COARSE FINE " I-COARSE •

SIEVE SIZE NUMBER 270 200 140 100 60 40 20 10 4 ¥a" 'j4 " I" 1%" 2" 3"

100 . : . , , ' , I ' I I I ' I ' UjJI ' I I . . ,.. - . I . !" ", , , I ' , • I I 1 I

! 1' 1 ! ! , I " ' ! 1 i : I I I I ! i II I I : I' 'I I ' ' " , I :' , I, i I I I ! , ., .,' I ·' , " ' " ' I ' I' " I ' . ,' I I: I I ,:/ , ,I I ' I ·.1 I. I: I I ; I I I : ' " " I I I ! I I' j " I I ! I

~ -'-,FT'-,'r' 'I i - r-L-LI· i :_-C-~" :I I -~ I-~·~r .. -t-il l-7" J;tili;I"'1 ; ' -I;~Tj -I-' i ,.17, I +Hj.::-l -;I 'I ~' " I I I ' I I' I' ,. I 'I r' , 'r 1 1 I " . I j I ~ I ~~' ++' I 11 -+J w .... . I ' !' r , . I I 1 ' I , I ' . I r . I , I , i

> 80 - - ,- '1 ' :- I ;....!._ .. - -t- .. :..! . _- - -~-. --:.- . . : .•. -. ,~.: tt--' -.......... . ,-' !::Y' ~/-. " : ' -- -, IJJ " '" 1 . " 1 I I I '" 1 I I 1 1 " '" I ,I I ' I I " I iii !· .. · , ' I. . ' " I' I " J J I 'I I ' l ; ! i' " I , ; 1 rlHft" 1 ~I . " . I I! r I I I, , , , . I ! 1

~ --:i N, . i-t- i-' I ~i ll t l - c - j h- r:~ : ~')~i~IHf ;11

-! I' ~ I :1: 1.

:1 o : ' , 1

11 , " ' " , "I : I I! ! H#' [' ''''''-: " 11,, I, ' 1 ~ 60 - ': , ; ;~-"'i I ,- I I Il.:--t-.... · I' -'1-it l-1-~r'-'~- -!l · " ~ "n · v--r-'I-' --, , ~" Ir ' 'I I ' ! I ~ r:-I ;-r-r I w J I I , . I ! 1 ! I , I I I I I ' ( V ! I I I , ' , I 1. 1: Il ;

'j , , ' I I 1- . I i I .. I I ' I ' I ' II: ,I , ,, I I '" [' ! I ' i I ' /' ',I,' , :;. " I ,i '~I g , -~-~ 7"1"7-1-, Ii'! ,.-1-- __ ;. -' " I·; - : I;":-I-I~t· : -·t ,·t·~ ! -~-~""":"'-'- '- IT I, I i - I~-t I ' U " Itffi ~'; ' '1" /' 'I L ,I , ' 'I' :,.1 ,' . , I • • , . ' ,! ' I·, t " I 1

~ 40 --;- :._L.:-L; . I. ,_ -1.:-1 .. -1-' II.tff, ; __ I_.L I / __ .:... I ... ~_~,L I ,... . ..... __ ,_ I _...:. .~_ I~' Ii ~ I 1_: ':.,.: 11_11,' I , i' l I I I , . I ,. , H I 1 /t' " 1 I " , , l " " :-1~1 I 'I '1 , f- I' :" 'I ' ! :, i ' I U; I ,', I I I' I ' , ill' ; 1 ' 1' "

! i I I 1 " .. 1 f ' , ,! 1 ' 'I " I ', I : , : f I, I ffi i-;':"r-J ' , ' f ~ .. L.:_.~ _' .. 1 . .:... ' : ry~J .. - ----'- T Ti' 1 -~-_ ___ ~ L,_ .. ~...I i UJ~ ~ , .: I" 1.1 ' 1, " I ' I' ,: ! ~' , I " I ' I I ! ' ,, ' I ,. , , 1

'1 1 l1. ' I"·· '''! I ' ,: 1 , , I 1 1 ' I I I , i" .. ; . I I" ! ! 1 i Ii ! " I · I I " J! 1 I ! ~ 20 .... ' 1I''':'n I ! i I , IL1t~ ._-ffiIIJ I.2J " . ,,' If_;...1 ! I, II II ml" I I

IJJ " " '1

1 I' II 1 " '1" I I I "'l 'rtrTl 'T]' :m'm' ffi' I I : I U j" _to! . , t I I I' I, ," : i : j I, : : !.! I I' : ! ' t I ! I I 0:: . . .. . i l ' . I '" I , I : ! t ! !! II i : i i , 1

IJJ ' I' ;" " [ , : Hfl '-I I " , . , ' I ' ttHH" a. ~ +-~.- ."- ' _ _ .. "C - -

I' i i ~ rrl,lll : ' : ;ifT ,,: " I: t I, i: II i , !: I I J. . L. j .• t. 1 : I '. ,; l I I .! ' . :

o : .. ! I' J I I ' .. ' J..I . I" . . I I I " ;

.005 .01 .05 0.1 0.5 1.0 5.0 10.0 50.0

• P- 5, 5- 4, depth 7'- 9 '

• P .. 5, 5- 7, depth 12'-14'

PARTICLE DIAMETER IN MILLIMETERS

GRAIN-SIZE DISTRIBUTION CHART

LAKE YOU NGS PERI METE R DI KE

King County, Washingt on f or EBASCO Serv ices , Inc.

(!) Converse Consultants Geolechnlcal Englneertng

.nd Applied Sclenc.s

Project No.

84- 5119 .. 12

-CLAY -1-- SILT -,-- SAND -I: GRAVEL :1

-- FINE - I-MEDIUM -I COARSE FINE , I-COARSE -

270 200 140 100 60 40 20 10 4 W 'A" 1" Ph" 2" 3"

100 , 1 I 'I I ' '

SIEVE SIZE NUMBER

. . l . 1 ,I 'I , I : I , I I ' I ' T I r I I r t I

I " . :. ! -, , , ; I I , I 'I ' : ' I : I " , I' " I I , ' ! I I' I ' , , ' , ' I " I' , ,1 ,,1 1 " "'1 , "1'1 "" II II ~ I I H-t1 w .:...1 ~" . II ~- -I--L-L";' -:-- I ,L l I 0 1 ' - I -...:--t "· ; -" ' I-~ --':'·j-!...;-;-----~---' _l_ I L.r-~ om: ' ; , , N ''' ''I I ' 'I' ' I ' I ' I ' " , ' " I ' , I I '/1 I ' I" " , Ui : I " , " . , 'I :: , ' : I , , , " I ' I I ': : !,;, I ' , I " I '

, J i ' ! i ' 1' \ ' I ' I '/ ' ' I " I I I " I !,.-1', 'I' I I II I I 't I I ~w 80 ~ 4--+-: "'1-1- -- ..:~ , ~ ", ·;I .. --I---L -:....~~-__ __ L.:..L..-__ , __ .~ __ L_Ll I~ -"I'-HI ;" -:-1:"'" --: 1 . t· · , I , , , I . . I ' j I . , 7) t· \, Ul- :, I' " I : , ! I , ' I

J

'I ;/ J ,. . J I 1[, : I 'J ';,/' ' , 1' 1: , I 'lJi I 'JI I , , I ' I ' ' I' . , It' I " I ' ,.. . .; , I I . , I " , , . I I ' ~ ,:", - ',-l~~~ , ~.-L..:., ,_:_. __ ,~ .. __ .' _____ -' 1 _ _ ; _ : --:--lL ,L.-- /.. , __ ,' '-~_:.J..j I . L i i : !_,_'

- ,'1'1 1 "1 1 ,,, " " 11'1" '1 I' I I ' II " I " ~"I I '…