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Attached please find copies of
9 PERMIT BILLS OF SALE
99 RECEIPT COST DATA INVENTORY
LETTER OF SPECIAL BILLING EASEMENT(S)
STUB SERVICE AGREEMENT COPY OF AS-BUILT
PRECON NOTES
PRECON ATTENDEES
DRAINAGE REPORT
FQ MEMO-WATER BREAKDOWN
MAP WITH NEW MAINS AND VALVES
WE OTHER 27
.�
r
From: - —
Date:
C T&PRECONAISTFRM
iW-6884-0 9
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1
1
iGeotechnical Studies
Renton Technical College
Building A - Addition
Renton, Washington
November 1994
-27 a/&�76
1
i
Renton Technical College
3000 N.E. Fourth Street
Renton, Washington 98056-4195
i NNW
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1 SHANNON 6WILSON, INC.
GEOTECHNICAL AND ENVIRONMENTAL CONSULTANTS
400 N. 34th St. - Suite 100
P.O. Box 300303 --�-j ON
CITY�:2EA:T'02i
Seattle, Washington 981µ03 E c E I V �`
206.632 .8020 �i D F
E111
SHANNON 6WILSON, INC. F RBNKS
HANFORD
GEOTECHNICAL AND ENVIRONMENTAL CONSULTANTS ANCHORAGE
SAINT LOUIS
BOSTON
1 4
November 28, 1994 40
Renton Technical College
3000 N.E. Fourth Street
Renton, Washington 98056-4195
Attn: Mr. Jon Pozega
' RE: GEOTECHNICAL STUDIES, RENTON TECHNICAL COLLEGE,
BUILDING A - ADDITION, RENTON, WASHINGTON
' This report presents the results of subsurface explorations and geotechnical engineering
studies for the proposed addition to Building A at the Renton Technical College, Renton,
Washington. The purpose of this study was to evaluate subsurface conditions at the site and
to provide geotechnical recommendations for the design and construction of the proposed
' structure. Our work included excavating four test pits and performing laboratory and
engineering analyses to develop design recommendations.
aAuthorization for our work was provided orally by Mr. Jon Pozega on November 17, 1994.
' SITE AND PROJECT DESCRIPTION
' The project site is located on the campus of Renton Technical College in Renton,
Washington and is shown on the Vicinity Map, Figure 1. The proposed addition will be
' located adjacent to and north of the existing Building A (near the south end of the campus).
It will be a single-story, slab-on-grade structure with plan dimensions of roughly 65 by 100
' feet. The location of the addition is shown on the Site and Exploration Plan, Figure 2.
Parking will be provided along the north side of the building.
It is our understanding that until recently the area of the proposed addition had been
occupied by several mobile structures. These have been removed, and at the time of our
' field work the site was relatively level and generally lacking vegetation except near the south
edge which was grass covered. The area of the addition was also observed to be relatively
dry at this time as well.
W-6884-01
400 NORTH 34 T H STREET•SUITE 100
' P.O. BOX 300303
SEATTLE,WASHINGTON 98103
206.632.8020 FAX206.633.6777
' Renton Technical College SHANNON 6WILSON,INC.
Attn: Mr. Jon Pozega
November 28, 1994
Page 2
' FIELD EXPLORATIONS
Subsurface explorations at this site consisted of excavating four test pits (designated TP-1
through TP-4) using a rubber-tired backhoe. The approximate locations of the test pits are
shown on the Site and Exploration Plan, Figure 2. The locations were determined by taping
from existing features and should be considered approximate. Elevations of the test pits are
shown on the test pit logs.
' The test pits were excavated with a backhoe provided by the owner. They ranged in depth
from 5.5 to 7 feet. The test pit excavations were observed and located by an engineer from
our firm, who visually identified the exposed soils, obtained representative samples, and
compiled a log of each exploration. All samples were sealed in plastic bags to preserve the
' natural moisture content and were returned to our laboratory for additional testing and future
reference. Logs of the test pits are presented on Figures 3 through 6. Relative densities of
the soil presented on the test pit logs were estimated based on probing of the walls and floor
' of the excavations and the relative ease or difficulty in excavation. The test pits were
loosely backfilled with the excavated material upon completion of the explorations.
LABORATORY TESTING
All samples were returned to our laboratory in Seattle, where each was visually classified
and its moisture content was determined. Moisture content information is included on the
test pit logs and the visual classifications were incorporated into the soil descriptions given
' on these logs.
' SUBSURFACE CONDITIONS
' The results of the test pit explorations indicate that in the area of the proposed addition the
soil consists of a fill that has been placed over the native soils. The fill extends to a depth
of between 4 and 6 feet. In general, the upper 6 inches consists of an orange-brown silty
sand, with scattered gravel. This material was of a medium dense consistency. Below this
depth the fill consists of a slightly silty to silty, gravelly sand. This material was brown,
1 dark brown, and gray-brown in color, had a slightly mottled appearance, and was dense.
W-6884-01
' Renton Technical College SHANNON 6WILSON,INC.
Attn: Mr. Jon Pozega
November 28, 1994
Page 3
' Generally, at the four test pit locations the fill was observed to be relatively free of
deleterious material. We observed one small piece of asphalt in test pit TP-1 at a depth of
12 inches, a thin layer of cemented whitish soil in TP-3 roughly 6 inches below the ground
surface, a small diameter PVC pipe in TP-2 about 6 inches below the ground surface, and
several electrical cables in TP-4, approximately 18 inches below the ground surface. In test
' pit TP-2 scattered fine to 1-inch-diameter roots were observed to a depth of about 10 inches.
It is our understanding that the PVC pipe and electric cables had been installed to service the
' structures that had previously occupied the site, and the whitish cemented soil was probably
the result of plaster that had been dumped on the ground surface in the past.
Underlying the fill in test pits TP-1 and TP-3 an orange-brown silty sand with scattered
gravel was encountered. This material was dense to very dense in TP-1 and medium dense
' in TP-3. Also, in TP-1 at the contact between the fill and underlying soil, a thin
(approximately 2 to 3 inch thick) layer of dark brown silty sand was observed. This
material was also dense and may represent a buried topsoil layer. In test pits TP-2 and TP-4
tthe fill was underlain by very dense clean, gravelly sand.
' Groundwater seepage was not observed in any of the test pit explorations, nor were any wet
and/or marshy surficial areas observed at the time our field explorations were accomplished.
1
' RECOMMENDATIONS
The test pit explorations indicate that the existing fill that is present in the upper 4 to 6 feet
' at the site consists of soils that are relatively free of deleterious material and that appear to
have been placed and compacted in a satisfactory manner. In our opinion, this material
should provide suitable bearing for footings.
' It is recommended that the proposed addition be supported on spread footings bearing in the
dense fill soils. Footings founded in this material may be designed for an allowable soil
bearing pressure of 2 kips per square foot (ksf). Minimum footing widths should be 24
inches for individual column footings and 18 inches for continuous footings. Footings
should be founded at least 18 inches below the lowest adjacent grade. Footing subgrades
' should be evaluated during construction by an experienced geotechnical engineer or his
W-6884-01
Renton Technical College SHANNON&WILSON,INC.
Attn: Mr. Jon Pozega
November 28, 1994
Page 4
' representative to verify the presence of competent bearing soil and to determine that all
loosened, disturbed soils, and objectionable debris have been removed prior to placing
' concrete.
The allowable bearing pressure given could be increased by one-third for wind or earthquake
' loads.
' Assuming compliance with the above recommendations, we expect settlements to be less
than 3/4 inches, with differential settlements (between adjacent footings or over a 20 foot
span of continuous footing) less than 1/2 inch.
' Lateral forces due to wind and/or seismic forces would be resisted bYpassive earth pressure
' against the buried portions of structures and by friction against the bottom. In our opinion,
passive earth pressures in backfill could be estimated using an equivalent fluid pressure of
280 pounds per cubic foot (pcf). These values assume that the structures extend at least 18
' inches below the lowest adjacent grade, and the backfill around the structure is a compacted
granular fill. The above values include a factor-of-safety of 1.5.
We recommend that a coefficient of friction of 0.5 be used between cast-in-place concrete
and soil. An appropriate factor-of-safety should be used to calculate the resistance to sliding
' at the base of footings.
' Footing subdrains consisting of slotted (or perforated), 4-inch-diameter, plastic pipe bedded
in washed 3/8-inch pea gravel should be installed around the perimeter of the structure. A
' detail is presented on Figure 7.
Wherever possible, surface storm water should be captured in strategically placed catch
' basins, and along with downspout water, conveyed from the site in a tightline. Surface and
downspout water should not flow onto the ground surface around the structure and should
' not be introduced into footing subdrain pipes.
A suitable subgrade for floor slabs or asphalt paving could be prepared at this site by
removing any surficial organics and compacting the exposed medium dense granular soils
with several passes of a heavy smooth-drum vibratory roller until a dense and unyielding
surface is achieved. Any soft or spongy areas revealed should be excavated and replaced
W-6884-01
Renton Technical College SHANNON&WILSON,INC.
Attn: Mr. Ion Pozega
November 28, 1994
' Page 5
with granular fill, then compacted and proof-rolling repeated. Also, if the test pit
explorations fall within this area, the loose backfill should be removed and replaced with a
densely compacted granular material.
Beneath floor slabs we recommend that a 6-inch-thick layer of washed pea gravel and a
' vapor barrier be placed as a capillary break. The vapor barrier could consist of plastic
sheeting placed on top of the gravel.
LIMITATIONS
The conclusions and recommendations contained in this report are based on the site
' conditions as they presently exist and assume that the explorations are representative of the
subsurface conditions throughout the site, i.e., the subsurface conditions are not significantly
different from those disclosed by the explorations. If, during construction, subsurface
rconditions different from those encountered in the explorations are observed or appear to be
present, we should be advised at once so that we can review these conditions and reconsider
' our recommendations where necessary. If there is a substantial lapse of time between the
submission of this report and the start of work at the site, or if conditions have changed due
to natural causes or construction activities at or adjacent to the site, it is recommended that
this report be reviewed to determine the applicability of the conclusions and
recommendations considering the changed conditions and time lapse.
' We recommend that we be retained to monitor the earthwork related portions of the
construction.
This report was prepared for the exclusive use of the Owner and Architect/Engineer in the
' design of the proposed facility. It should be made available for information of factual data
only, and not as a warranty of subsurface conditions, such as those interpreted from the
' exploratory logs and discussions of subsurface conditions included in this report.
Unanticipated soil conditions are commonly encountered and cannot be fully determined by
merely making explorations and taking samples. Such unexpected conditions frequently
require that additional expenditures be made to attain a properly constructed project.
Therefore, some contingency fund is recommended to accommodate potential extra costs.
W-6884-01
Renton Technical College SHANNON 6WILSON,INC.
Attn: Mr. Jon Pozega
November 28, 1994
Page 6
Shannon & Wilson, Inc. has prepared the attachment, "Important Information About Your
Geotechnical Engineering Report" to assist you and others in understanding the use and
limitations of our reports.
If you have any questions regarding our recommendations, please contact us at
(206) 632-8020.
' Sincerely,
SHANNON & WILSON, INC.
ySOHN
ot vrasy����C�
Reviewed by:
' NALL-n1 U
EXPIRES 411195
Michael J. Wolczko, P.E. Thomas M. Gurtowski, P.E.
' Senior Engineer Senior Associate
MJW:TMG/mjw
' Enclosures: Figure 1 - Vicinity Map
Figure 2 - Site and Exploration Plan
Figure 3 - Log of Test Pit TP-1
Figure 4 - Log of Test Pit TP-2
Figure 5 - Log of Test Pit TP-3
Figure 6 - Log of Test Pit TP-4
Figure 7 - Typical Footing Subdrainage Scheme
Important Information About Your Geotechnical Engineering Report
W6114-01.LT2/W 6884-1kd/dgw
W-6884-01
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' 0 1/4 1/2 1 Renton Technical College
Building A- Addition
' Scale in Miles Renton, Washington
NOTE VICINITY MAP
' Map adapted from USGS topographic November 1994 W-6884-01
map of Renton, WA quadrangle, dated
1949, photorevised 1968 and 1973. SHANNON &WILSON, INC. FIG. 1
' Geok)&mal and Environmental consultants
= Z
LV.+ITS CF
CENTRAL HEATING �
STAGING ARE APE
A
' I BUILDING 'C'
N
NEW EOLNP,
SEE —
EXISTT VA VA LIT I EXIST SIDEWALK .-0•
EXIST EOUP PAD �--�/
M EXIST TRAM SFOQKCR I U�1' 1 5
EXIST LANDSCAPING U LJ^, 2 TYP.V 4M2 CONC PAVING
TLO -_TOE IST CQ. S—CIV TO E 4t�.oC�
. '. ��C`TKO EX35T OQAm6 1
REMOVE EXIST PAVING.TYP REP .J •',
EXIST CS TO BE LACED.
SEE avlL T 2 I --I
F ----J L IVILT.
------- - i I r--- _� i
I � U `
TY
�
TP-2 �g
{� A
I !t 1 TiP4 L���U PEMOVE EXIST
'yrr LEGEND
12EnaOoa a m
. AREA r't a / A151M o�Foc�issP TP-1 �'9 Test Pit Designation and
as N .', BuvAs — Approximate Location
MCCORMICK /1�: fj
�
EXISTING BUILDING 'A'
I I bw&4 ri B 4 A.viz Tv. `� sA j 0 30 60
_ r � '
�+DDITION AREA
I )" 65a35F �. Scale in Feet
r
F , 2
1•vf 251A2 b
FOR STRIPING o
- - - iyP3
�r TP-1 NOTE
This figure is based on 'Site Plan"
1 �ITI %� prepared by Waldron Pomeroy Smith
y� I/ REMOVE EXIST PAVING,TYP Foote & Akira Architects, dated 11-4-94.
L EXIST BOLLARD''TO REMAIN MAOVE EXIST CONC CLAPS.TYP
4 EXIST PENCE AND GATE TO REMAIN
+/ EXIST APNOLTIC CONC TO RFJMAN`-, sAwcLrr AND
12500vE EXIST
EXIST CUM Renton Technical College
TO REMAIN - Building A-Addition
j Renton, Washington
EXIS 7 PORTABLE B JILDING
NORTH SITE AND EXPLORATION PLAN
rNovember 1994 W-6884-01
SHANNON &WILSON,INC. FIG, 2
C*obdrical and Effam nta!Ca><arlla
SHANNON &WILSON, INC.
Geotechnical and Environmental Consultants JOB NO: W-6884-01 DATE: 11-18-94 LOCATION: See Site Plan
LOG OF TEST PIT TP-1 PROJECT: Renton Technical College-Building A Addition
" Sketch of NW Pit Side Surface Elevation: Approx. 331 Feet
SOIL DESCRIPTION o E
0
0 `ca 0 0 2 4 Horizontal Distance in Feet 8 10 12
29.6 S-1 0 1 . . . . . . . . i . . . . . . . . . . . . . . . . . . .
OMedium dense, orange-brown, silty : : : Small Piece • • • .
SAND, scattered gravel; moist; a . • • • . . . . of Asphalt : . ' • ' • • • • . . . • . • ' ' ' ' •
CID . . . . . . . . . . . . . . . . . . . . . . ? . . . . . . . . . ' . . . . . . . . .
. . . . : . . . . . . . . . . . . . . . . . . : . . . . . . . ; . . . . . . . . . ; . . . . . . . . .
m . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
rn
2 Dense, mottled, light brown, dark 8.5 S-2 2 .................... ........................e................................................ i
O :.................... ............. ........... ............................. ..
brown, and gray-brown, slightly : : : . . : . : . : . . : : . : . . : . . : :
silty to silty, gravelly SAND; moist; CZ
. . . . . . . . . . . . . . . . . . € . . . . . . . . . . . . . . . . . . . . . . . . . . .
O3 Dense, dark brown, silty SAND; I . : : : : : : :
moist; (Topsoil). 0 4 ................................................i..... .......................................�... 3 ._................................;..... :...:........:....:....:...._....: :........................I............... .._...................._.................
z . . . . . . . . . . . . . . . . . . . : . . . . . . . . . . . . . . . . . . . . . . . . . .
® Dense, orange-brown, silty SAND, 31.6 S-3 : : . . . . . . . . . . . • • . • O . . . . . . . . . . . . . . . . . . . . . . . . . . : :
scattered gravel; moist.
6 ................_..................................................:.........:............. .......................................... ........................................: ...................................................._....................................
8 ........................._..........._.............................:................._ .......................................... :.._:.._:............................................................................................................:...............
10 _................_............_. ............................................................._...................._........ .......................................... ..........................................
In . . . . . . : : :
12 . . . . . . . . . . . . . : : . . . . . . . . . . . . . . . . . . . . . . . .
SHANNON &WILSON, INC.
Geotechnical and Environmental Consultants JOB NO: W-6884-01 DATE: 11-18-94 LOCATION: See Site Plan
LOG OF TEST PIT TP-2 PROJECT: Renton Technical College - Building A Addition
CD a Sketch of SW Pit Side Surface Elevation: Approx. 331 Feet
SOIL DESCRIPTION o o E a Horizontal Distance in Feet
CZ° v `° 00 2 4 6 8 10 12
22.8 S-1 0 1 . : : : : : : . . 1 . . . . . . . . . . . . . . . . . .
OMedium dense, orange-brown, : : : : : : . . . . . . . . . . : :
silt gravelly SAND; moist; mixed : 1/2" Diameter : :Some Roots Down to 10"
y g y . . . . . . . . PVC Pipe . . . . . . . . . . . . . . . -Fine to 1"Diameter . . . .
with dark brown, organic, silty . . . . . . . . . : . . . . . . . . . . . . . . . . . . . . . .
SAND; (Fill). °' . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
0 2 ..... .......................................................................................f............................................ ........................... .............................................t................................................
.
O ....i...».... ..
ODense, brown, slightly silty to silty, 10.6 S-2 • . . . . . . : : : : • • • • • • •
gravelly SAND; moist; (Fill). CU
. . . . . . . . . . . . . . . . . . .
® Very dense, gray-brown, dark o : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : :
brown and black, silty, fine : . . . . . . . . € • • . . . • . . • . • • • . • .
SAND/fine sandy SILT; moist; 0 23.5 S-3 4 -- - g _
....»..._....................................._............ ................_..... ........_................_............. ............._................ »....................
iron-oxide staining; (Fill). Z . . . . . . . . . . : . . . . . . . . . . . . . . . . . . . . . . . . . . .
® Very dense, brown, clean, gravelly : : : : : : : : : : : : : . . . . . . . . . : : : : : . . . . : : : : : : : : : : : : : : : : :
SAND; moist. . . . . . . . . . . . . . . . . . . 3 . . . . . . . . . . . . . . . . . .
8.6 S-4 6 ....:...........................................;...... .............................................................................................................................. _............»......._..._.y......................»........................
e....» ....
. . . . i . . . . . . . . . . . . . . . . . . . . .
8 ...»........»....................................................................._...... .__.._..._.._........_.. .._......._ ......................................_ ........................................................._..._.............................._
10 ....................._...... ............................... ......................................... _...».......-......................... .......».................................... ..........................................
n
12 . . . . . . . . . . . . . . . . . .
SHANNON &WILSON, INC.
Geotechnical and Environmental Consultants JOB NO: W-6884-01 DATE: 11-18-94 LOCATION: See Site Plan
LOG OF TEST PIT TP-3 PROJECT: Renton Technical College- Building A Addition
� �, �' Sketch of SW Pit Side Surface Elevation: Approx. 332 Feet
SOIL DESCRIPTION o c E CL Y
v CL 0 0 2 4 Horizontal Distance in Feet8_0 8 10 12
0 . . . . . . . . 1 . . . .
OMedium dense, orange-brown, Cemented Seam
silty, gravelly SAND; moist; (Fill). a . • • • • • . • . . . • . . • • ` • . . . . . . . . € . • . . . . . . . . . .
. . . . . . . . : . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -1"Thick
Z (Plaster?)
2O Dense, mottled brown and : : : : : . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
gray-brown, slightly silty, gravelly 2 ...... .......................................................................-............-?.......................:........:....:..................................................a............... .....:-................:... ...:-......._................_......-:._.
SAND; moist; (Fill). — . . . . . : : : : : : : . : : : : : . . . . . . . . . . . . . .
O3 Medium dense, orange-brown, silty : : : : : : : : : : : : : : : : : : 2 : : : : : : : :
SAND, scattered gravel; moist.
. . . . : . . . . . . . . . i . . . . . . . . . . . . . . . . . . . . . . . . . . .
� 9.2 S-1 .
o . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4 ..................... ........._................................................ ........................................: ..._.._.._........_.:_.......: ......................_......._......: ......................................-:o . . . . . . . . . . . . . . . .
z . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6 ..........................._......._..........p...._... . . . . . . .....'. ......................... ........................_.............................»..................._......
14.5 S-2 : : : : : : : : : . . . " . . . . . . . . . . . . . . . . . . . . . . . .
8 .............................................................................................. :........................................ ............................_...........................................................................................................
10 _.:.....:.....:.....................:...._:....:....:._.:....:....:....:....:....: :....:....:....:...:....:....:....:....: :....:....:....:..........................._ :....._......:....:....:....:......_: _ ..........................................
T ....(.... ....... ... '
12 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SHANNON &WILSON, INC.
Geotechnical and Environmental Consultants JOB NO: W-6884-01 DATE: 11-18-94 LOCATION: See Site Plan
LOG OF TEST PIT TP-4 PROJECT: Renton Technical College - Building A Addition
° Sketch of West Pit Side Surface Elevation: Approx. 332 Feet
ca-
SOIL DESCRIPTION o c E C
0 cn Horizontal Distance in Feet
° 0 0 2 4 6 8 10 12
14.9 S-1 0 1 . . . . . . . .
. . . . . . .
Sod overlying medium dense,
. . . . . : . . . . . . . . .
orange-brown, silty, gravelly SAND; . . . . . . . i . • • . . . . . . : . . . . . . . . . . . . . . . . . . . . . . . . .
moist; (Fill). : : : : : : : : : . . . . . . . . . . : : . . . . . . . . . . . . . .
Aluminum Wire
20 Dense, mottled, brown and dark 3 2 ............. ................................:...._..................................._......_............. ........................ ..........................................i.................._.............-:.........
brown, silty, gravelly SAND; moist; _0 . . • . . . . . . . . . . . .
(Fill). c . . . . . . . . . . . . . . . . : : : . . . . . . : : : : : : : :
8.5 S-2 : 20 : . . . . .
(D
O3 Very dense, brown, clean, gravelly o • • • •
SAND; moist. Z : : : : . : : : : : : : : : : : : : : : : : :
4 ................._........... ...............i.............................................._i.-..-..._.........................._......................... ...:.................................................._................ _............_......
6 :....: . . . . . ..._...................._............: ......................................... .......................................
g . . . . . . . . . : . . . . . . . . . : :....:....:....:....:....:_..:....:...: ..........-....:....:....:........: :.....:....:...._......._..._..._...................r_..............................................}.................................................... _.....
10 ......................_...................... .......................................... ..................................................................-.........................._............_.........................._....
r.............................................
12 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Top of Floor Slab
' Located Slightly Higher
Than Outside Grade
Sloped to Drain Vapor
Away From Structure Barrier
Floor Slab
p• p ° O o ° Q• ° ° o o O O
' Pavement or 9"to 12"of Tamped, po°o, 1 D•• ;o' °: o a0o Drainage ' °, ° 4„° °
Impervious Soil or Topsoil ° ° ' °• ° o C. ° Sand&Gravel
Weep Holes o°°- 24 or Pea Gravel Min.oD
1 y
(See Note 1) ° Min.°°0e °o:°• •o•; •o o,• o
° • p
° O-0° O O v
O° a
O ° °
• °°'o e ° o Oo 0 00 0 ° ° ° ° °°
°°O
6"Min. Cover of Washed •o ° • •°•,
Pea Gravel or Drainage °° •o•° p ° o Spread or °o
Sand&Gravel ••o ° •° •o o Continuous °o
(On All Sides of Pipe) ° 2"to 4'; o Footing °
Subdrain Pipe
' Not to Scale
' MATERIALS
1. Washed Pea Gravel : 3/8"to
No. 8 Sieve Size NOTES
2. Drainage Sand&Gravel with 1. Drainage gravel beneath floor slab
the Following Specifications: should be hydraulically connected to
' subdrain pipe. Use of 2"dia.weep holes
%Passing as shown is one applicable method.
Sieve Size by Weight
1-1/2" 100 2. If floor slab is located below outside
3/4" 90 to 100 grade, place washed pea gravel or
1/4" 75 to 100 drainage sand and gravel against wall
(18"min.out from wall)extending from
' No.8 65 to 92 pea gravel zone shown above up to
No.30 20 to 65 pavement or impervious zone.
No. 50 5 to 20
No. 100 0 to 2
(by wet sieving) (non-plastic)
' SUBDRAIN PIPE
Renton Technical College
4" minimum diameter perforated or slotted, Building A- Addition
concrete, metal,or plastic;tight joints;sloped to Renton, Washington
' drain (4"/100' min.slope);provide clean-outs.
TYPICAL FOOTING
Perforated pipe holes(3/16"to 1/4"dia.)to be SUBDRAINAGE SCHEME
in lower half of the pipe with lower quarter
segment unperforated for water flow. November 1994 W-6884-01
Slotted pipe to have 1/8" maximum width slots. SHANNON&WILSON, INC.
' Geotechnical and Environmental Consultants FIG• 7
W-6884-01
SHANNON & WILSON, INC. Attachment to Report Page 1 of 2
Geotechnical and Environmental Consultants Dated: November 28, 1994
' To: Renton Technical College
Attn: Mr. Jon Poze�ra
Important Information About Your Geotechnical Engineering/
iSubsurface Waste Management (Remediation) Report
' GEOTECHNICAL SERVICES ARE PERFORMED FOR SPECIFIC PURPOSES AND PERSONS.
Consulting geotechnical engineers prepare reports to meet the specific needs of specific individuals A report prepared for a civil
engineer may not be adequate for a construction contractor or even another civil engineer. Unless indicated otherwise, your consultant
prepared your report expressly for you and expressly for purposes you indicated. No one other than you should apply this report
for its intended purpose without first conferring with the consultant. No party should apply this report for any purpose other than
that originally contemplated without first conferring with the geotechnical engineer/geoscientist.
' AN ENGINEERING REPORT IS BASED ON PROJECT-SPECIFIC FACTORS.
' A geotechnical engineering/subsurface waste management (remediation) report is based on a subsurface exploration plan designed
to consider a unique set of project-specific factors. Depending on the project, these may include: the general nature of the structure
and property involved; its size and configuration; its historical use and practice; the location of the structure on the site and its
orientation;other improvements such as access roads, parking lots, and underground utilities;and the additional risk created by scope-
of-service limitations imposed by the client. To help avoid costly problems, have the consulting engineer(s)/scientist(s)evaluate how
any factors which change subsequent to the date of the report, may affect the recommendations. Unless your consulting geotechnical/
civil engineer and/or scientist indicates otherwise,your report should not be used: 1)when the nature of the proposed project is changed
(for example, if an office building will be erected instead of a parking garage, or if a refrigerated warehouse will be built instead of
an unrefrigerated one, or chemicals are discovered on or near the site); 2) when the size, elevation, or configuration of the proposed
project is altered; 3) when the location or orientation of the proposed project is modified; 4) when there is a change of ownership;
or 5)for application to an adjacent site. Geotechnical/civil engineers and/or scientists cannot accept responsibility for problems which
may occur if they are not consulted after factors which were considered in the development of the report have changed.
SUBSURFACE CONDITIONS CAN CHANGE.
' Subsurface conditions may be affected as a result of natural changes or human influence. Because a geotechnical/waste management
engineering report is based on conditions which existed at the time of subsurface exploration, construction decisions should not be
based on an engineering report whose adequacy may have been affected by time. Ask the geotechnical/waste management consultant
to advise if additional tests are desirable before construction starts. For example, groundwater conditions commonly vary seasonally.
' Construction operations at or adjacent to the site and natural events such as floods, earthquakes, or groundwater fluctuations may also
affect subsurface conditions and, thus, the continuing adequacy of a geotechnical/waste management report. The geotechnical/civil
engineer and/or scientist should be kept apprised of any such events, and should be consulted to determine if additional tests are
necessary.
MOST GEOTECHNICAL RECO1k1 ENDATIONS ARE PROFESSIONAL JUDGMENTS.
Site exploration and testing identifies actual surface and subsurface conditions only at those points where samples are taken. The data
were extrapolated by your consultant who then applied judgment to render an opinion about overall subsurface conditions The actual
interface between materials may be far more gradual or abrupt than your report indicates. Actual conditions in areas not sampled
may differ from those predicted in your report. While nothing can be done to prevent such situations, you and your consultant can
' work together to help minimim their impact. Retaining your consultant to observe subsurface construction operations can be particu-
larly beneficial in this respect.
A REPORT'S CONCLUSIONS ARE PRELIMINARY.
The conclusions contained in your geotechnical engineer's report are preliminary because they must be based on the assumption that
' conditions revealed through selective exploratory sampling are indicative of actual conditions throughout a site. Because actual
Page 2 of 2
subsurface conditions can be discerned only during earthwork,you should retain your geotechnical engineer to observe actual conditions
and to finalize conclusions. Only the geotechnical engineer who prepared the report is fully familiar with the background information '
needed to determine whether or not the report's recommendations based on those conclusions are valid and whether or not the
contractor is abiding by applicable recommendations. The geotechnical engineer who developed your report cannot assume
responsibility or liability for the adequacy of the report's recommendations if another party is retained to observe construction.
THE GEOTECHNICAL ENGINEERING/SUBSURFACE WASTE MANAGEMENT (REMEDIATION) REPORT IS
SUBJECT TO MISINTERPRETATION.
Costly problems can occur when other design professionals develop their plans based on misinterpretation of a geotechnical ,
engineering/subsurface management(remediation)report. To help avoid these problems, the geotechnical/civil engineer and/or scientist
should be retained to work with other project design professionals to explain relevant geotechnical, geological, hydrogeological and '
waste management findings and to review the adequacy of their plans and specifications relative to these issues.
BORING LOGS AND/OR AIONITORPgG WELL DATA SHOULD NOT BE SEPARATED FROM THE
ENGINEERING/WASTE MANAGEMENT REPORT. '
Final boring logs developed by the geotechnical/civil engineer and/or scientist are based upon interpretation of field logs (assembled
by site personnel), field test results, and laboratory and/or office evaluation of field samples and data. Only final boring logs and '
data are customarily included in geotechnical engineering/waste management reports. These final logs should not, under any
circumstances, be redrawn for inclusion in architectural or other design drawings, because drafters may commit errors or omissions
in the transfer process.
To minimize the likelihood of boring log or monitoring well misinterpretation,contractors should be given ready access to the complete '
geotechnical engineering/waste management report prepared or authorized for their use. If access is provided only to the report
prepared for you, you should advise contractors of the report's limitations, assuming that a contractor was not one of the specific '
persons for whom the report was prepared and that developing construction cost estimates was not one of the specific purposes for
which it was prepared. While a contractor may gain important knowledge from a report prepared for another party, the contractor
should discuss the report with your consultant and perform the additional or alternative work believed necessary to obtain the data
specifically appropriate for construction cost estimating purposes. Some clients hold the mistaken impression that simply disclaiming
responsibility for the accuracy of subsurface information always insulates them from attendant liability Providing the best available
information to contractors helps prevent costly construction problems and the adversarial attitudes which aggravate them to a
disproportionate scale.
READ RESPONSIBILITY CLAUSES CLOSELY.
Because geotechnical engineering/subsurface waste management (remediation)is based extensively on judgment and opinion, it is far
less exact than other design disciplines This situation has resulted in wholly unwarranted claims being lodged against geotechnical/
waste management consultants. To help prevent this problem, geotechnical/civil engineers and/or scientists have developed a number '
of clauses for use in their contracts, reports and other documents. These responsibility clauses are not exculpatory clauses designed
to transfer the engineer's or scientists liabilities to other parties; rather, they are definitive clauses which identify where the engineer's
or scientist's responsibilities begin and end. Their use helps all parties involved recognize their individual responsibilities and take
appropriate action. Some of these definitive clauses are likely to appear in your report, and you are encouraged to read them closely. '
Your engineer/scientist will be pleased to give full and frank answers to your questions
The preceding paragraphs are based on information provided by the '
ASFE/Association of Engineering Firms Practicing in the Geosciences, Silver Spring, Maryland
2/94