HomeMy WebLinkAboutEisenbeis Block 99 - Geotechnical Engineering Services - 1999.01.15J
Geo
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Madrona Medical partners
c/o Rigby Architects
5327 West Mercer Way
Mercer Island, Washington 9g040
Attention: Doug Rigby
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January 15, 1999
Consulting Engineers
and Geoscientists
Offices in \.Vashington.
0regon, and AIaska
Report
Geotechni cal Engineering Servicesfroposed Medical Clinic Building
lOth Avenue and Sherid- Au.nu-"Port Tor.vnsend, Washington
File No. 7174-001-00
rhis report presents the resurts "lTll:i,y;]';,i-ineering services ror the proposedmedical clinic building to be located at IOth Avenue and sheridan Avenue in port Townsend,washington' our services have been completed in general accordance with the scope presented
;:#J?;:i'#-'December lt' lees our services were authorized by Doug Rigby on
we understand that the proposed project includes two phases of construction. The first phasewill include construction of an appro*i,nor.ty 7,500 square foot crinic buirding on the south harfof the property' The second phase will be an addition on the north half of the property connectedto the structure contpleted during the first phase. we also understand that the proposed two-storybuilding will include lvood-frante construction with an on-grade floor srab. The rower floor revelwill day-light to the east' The building will therefore incruJe retaining wars on the west side, andportions of the north and south sides, of the structure.
The purpose of our services ,, ," 0"";;o;5gn .rit.ri" for geotechnicat aspects of theproposed project. our specific scope of services incrudes the fouowing tasks:l' Explore subsur ce soil and ground water conditions by excavating five test pits to depths of5.5 to 7 feet using a rubber_tired backhoe. "J v'rvsv4''E 'vs rc
2' Evaluate pertinent physical and engineering characterisiics of foundation soirs based onlaboratory testing performed on samples obtained from the test pits. The raboratory testingGeoEngineers, lgpnsists of moisture content determinations.
Plaza 600 Building
600 Srewart Sr., S uite l2l5
Seartle, WA 98101
'l'elephone (206) I zs_267 4
FrLr (206) 728.27 32
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Printed on recycled paper
Madrona Medical partners
January 15, 1999
Page 2
3' Develop recomrnendations for site prepaiation and earthrvork, incruding evaruating thesuitability of the on-site soils for use as structurar fiil and recommendations for pracementand compaction of structural fill.4'
#::il:ommendations
for temporarv cut slopes, and permanenr cut and fiil sropes, as
5' Develop recommendations for shallow foundation support. This includes recommendationsto reduce the risk of post-construction settlement and for lateral resistance.6' Provide lateral earth pressure values for design of berow-gr"o;*;,lr;;retaining strucrures,including a coefficient of base friction to resist taterar forces.7. Provide recommendations for support of on_grade floor slabs.8' Provide recommendations for temporary and permanent drainage improvements. This
;:*:;JHHir::,,::: for a berow_,rou "op'r""'i** and moisture rerarder, and
9' Prepare a written report presenting our concrusions and recommendations together withsupporting field and laboratory data.
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The site is bordercd by IOth Avenue to the south, I lth Avenue to the north, sheridan Avenueto the west and cleveland Avenue to the east. The site location is shown on flie vicinity Map,Figure l' An existing single-family residence and dctached garage/srrop building with a grassedyard area are located on the south portion of the site. A driveway provides o"..rr1o the residencefrom sheridan Avenue and l0th Avenue. The garage/shop is accessed from the driveway offoflotlr Avenue' The ground surface slopes down to the east, from about Elevation 204 arongSheridan Avenue to about Elevation 195 along the right-of-way for creverand Avenue. Theseelevations are based on an assumed datunr presented on the site survey by wood surveying, Inc.of Port Townsend, washington (filed for record December 4, I99g). Based on the ground surfaceconditions we expect that up to two feet of fill is likely present around the north side of theresidence and the north and east sides of the garage/shop buirding. The site is currentry vegetatedwith a grass yard area around the single-family residence and along much of the south portion ofthe site' and willow' blackberrit', ,olol and scattered madrona and conifers in trre undeveropednorth portion of the site' The site and surrounding area are shown on the site pran, Figure 2.
SITE DESCRIPTIONSURFACE CONDITIONS
SUBSURFACE CONDITIONSExplorations
Subsurface conditions were explored by excavating five test pits at the site on Decemb er 23,1998 using a rubber-tired backhoe owned and operated by Lindsey Excavating of port Townsend,washington' Locations of the explorations were determined in the field by measuring distancesfrom prope4y boundaries and site features. Ground surface elevations were estimated from
GeoEngineers
File No. 7174{01{0-l 130
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Madrona Medical partners
January 15, 1999
Page 3
Laboratory Testing
Soil Conditions
Ground Water
topographic information given on the site survey deveroped by wood surveying, Inc. and datedDecember 4' r99g. The locations of the test pits are shorvn in Figure 2.The test pit excavations lvere continuously monitored by a geotechnical engineer from ourfirm rvho examined and classified the soils encountered, obtainea representative soit sampres,observed ground water seepage conditions and prepared a detailed log of each exploration. soilswere classified in general accordance with the classification system described in Figure 3.The test pit logs are presented in Figures 4 through 6. These logs are based on ourinterpretation of the field and laboratory data and indicate the various types of soirs en-countered.They also indicate the depths at rvhich the soils or their characteristics change. The densitiesnoted on the test pit logs are based on the difficulty of digging and our experience and judgment.
The soil sanrples obtai.ed from the test pits rvcre fi:rtrrer examined in our laboratory.Moisture content deternrinatiotls rvere made on serected sampres for correlation purposes. Theresults of these deterrninations are presented in Figure 7.
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In general' the subsurface soil conditions are consistent across the site. An upper rayer oftopsoil and rootmass about 3 to 6 i'ches thick overlies shallow thicknesses of fill material nearthe existing structures and native soil elscwhere. we did not excavate test pits in the yard areawhere fill is evident' However, based on our observation of the fiil srope arong the north and eastsides of the garage/shop building we expect that up to 2 to 3 feet of roose to medium dense sirtysand with graver comprises the fi, on th; soutrr portion of trre site.The original topsoil and rootritass layer encountered in undeveloped portions of the site, isabout 6 inches thick' Generally, glacial till consisting of medium dense to dense silty sand withgravel and occasional cobbles was encou'tered below the topsoir and rootmass in the test.pits.The glacial till grades to very dense at depths ranging from about 3 to 5 feet in test pits Tp-2
ffi-ir;.Tl*f" '"t' pits TP-l the glacial till remained dense to the botrom of the test pit at a
No ground water seepage was observed in the test pit explorations. we expect the groundwater at the site to vary as a function bf season, precipitation, and other factors and perchedground water may be present during extended periods of wet weather.
GENERAL coNcLUStoNs AND RECOMMENDATTONS
It is our opinio' that the site may be satisfactoriry deveroped as proposed using sharowfoundations supported on the medium dense to very dense glacial till soils encountered in theexplorations' oron properly compacted structural fill. Fill is present in the south portion of the
GeoEngineers
File No. 7174{OI{0-l t30
Madrona Medical Partners
January 15, 1999
Page 4
site around the existing residence and garage/shop building. We recommend that all existing fill
in the south portion of the site, and elsewhere if encountered during site grading, be removed
from the building area and be replaced with properly compacted structural fill as necessary to
achieve design grades.
We expect that perched ground water will likely be encountered in the near surfuce soils
during excavation if the grading rvork is undertaken during extended periods of wet weather. It
lvill be necessary for the contractor to use appropriate construction techniques to reduce the risk
of disturbing the bottonr of footing excavations during site earthrvork.
SITE PREPARATION AND EARTHWORK
General
We recommend that site preparation and earthwork be completed during the normally dry
season of the year (genbrally June through September) as the on-site soils are moisture sensitive
and will be diffrcult to work with during extended periods of wet weather.
In preparing the site for corrstruction, building and paved areas should be cleared of
vegetation and stripped to remove roots. We expect that the depth of stripping will generally be
about 6 inches, but areas of greatcr stripping dcpths may be present. The stripped material may
be reused in landscape areas or disposed of offsite.
We expect that the native soil encountercd in our test pits can be excavated witlt conventional
earthwork equipurent. It rrray be necessary, holvever. to rip the very dense glacial till in the
deeper portions of the building and utility excavations.
Temporary and Permanent Slopes
We expect cuts up to about 6 to 8 feet high may be required along the west portion of the
building area to establish the proposed building subgrade elevation. For planning purposes, we
recommend that the sides of tenlporary excavations in the dense to very dense glacial till be
sloped no steeper than lH:lV (horizontal to vertical). Flatter slopes, no steeper than l-l/2H:lV,
will be necessary in the overlying medium dense soil. The final configuration for temporary
excavation slopes should be evaluated during construction.
Permanent cut and fill slopes should be inclined.no steeper than 3H:lV. Permanent slopes
should be planted or hydroseeded as soon as practicable after grading. We recommend that all
fill be placed as structural fill, as described below.
Subgrade Preparation
We recommend that the native soils exposed by stripping within the planned building and
paved areas'be proofrolled by heavy rubber-tired equipment or a roller if site preparation is done
during dry weather. During wet weather, the exposed areas should be probed to determine the
extent of soft soils. Any soft areas which are encountered during proofrolling or probing should
be removed and replaced with compacted structural fill.
CieoEngineers File No. 7174-001'00'1 130
Madrona Medical partners
January 15, I999
Page 5
AII existing building foundation, slabs and utilities shourd be removed during initial siteil::ilr;.;,ffi"ff:j:il,?,,il".' subgrade erevation that are created during this process
we also recommend that the upper one foot of the native soil exposed at subgrade elevation
;r'#Tifilr:""t*tnt areas be compacted to at reast 95 percent of maximum dry density (per
AII fill placed in pavement, footing and floor slab subgrade areas and to construct permanentfill slopes should be praced as structurar fiil.
ev grve dru Lu constl
on-site excavated soil consisting of silty sand with gravel (glacial till) may be considered foruse as structural fill only for placement during periods Jp.orong"d dry weather, provide that thesoil can be conditioned to the proper moisture content for achieving adequate compaction. [n ouropinion' this will likely be possible if construction takes prace during the normary dry season ofthe year (generally June through September).
Imported structural fill should consist of sand and graver containing ress than 5 percent fines(material passing thc No. 200 sieve) by weight relative to the fraction passing the 3/4_inch sieve.Soil containing rocks larger tha' 6 i'ches in size or debris such as organic soirs, roots, wood,asphalt and concrete fragments srrourd be excruded fro'r structurar fiil.Structural fill should be placed in loose lifts not exceeding g inches in thickness andcompacted to at least 95 percent of tlre maximum dry density as determined by the
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method' Permanent slopes in structural firs shourd be estabrished at no
we recommend that a representative from GeoEngineers, Inc. be present during structural fillplacement to observe the work and per:form in-place density tests to evaluate whether or not thespecified compaction is being achieved.
FOUNDATION SUPPORT
we recommend that the planned clinic building be supported on spread footings founded onthe medium dense to very dense silty sand with graver encountered in our exprorations, or onproperly compacted structural fill extending down to these soils. where structural fill is placed toachieve design grade for footings, the zone of structurar fiil shourd extend beyond the faces of thefooting a distance at least equar to the thickness of the structurar fir.we expect the exposed bearing surfaces in footing excavations will become softened,Ioosened or disturbed if not """futly protected frorn exposure to moisture and constructionactivities' Therefore' lve recomntend that the footing excavations be made during periods of dryweather and that all footing excavations be examined by a representative of our firm prior toforming footings or placing structural steel.
Structural Fill
GeoEngineers
File No. 7l7441l4}-t t3O
Madrona Medical Partners
January 15, 1999
Page 6
We recommend minimunr rvidths of 16 inches and 24 inches for continuous and isolated
spread footings, respectively. The depth of embedment for all exterior footings should be at least
24 inches below lowest adjacent finished grade. Interior footings should be founded at least
12 inches below adjacent grade or the bottom of the floor slab. For foundations designed and
constructed as recommended, an allowable bearing pressure of 3,000 pounds per square foot (psf)
may be used. This value applies to the total of dead and long-term live loads exclusive of the
weight of the footing and any overlying backfill.
We estimate that postconstruction settlement of footings founded on the medium dense to
very dense glacial till rvill be less than l/2 inch. The postconstruction settlement of footings
founded on properly compacted structural fill may range from l/2 to I inch, depending on the
actual foundation loads and the thickness of fill beneath the footings. Marimum differential
settlement along 25 feet of continuous footing or betrveen adjacent comparably loaded isolated
cotumn footings should bs less than l/2 inch. We expect that most of the footing settlement will
occur as loads are applied.
BELOW.GRADE WALLS AND RETAINING STRUCTURES
The following recommendations should be used for the design of below-grade walls which
are intended to act as retaining structures and for other retaining structures that are used to
achieve grade changcs.
Positive drainage should be provided behind below-grade walls and retaining structures by
placing a zone of clean (less than 3 percent passing the No. 200 sieve), medium to coarse sand
with fine gravel against the wall. This drainage zone should be at least 18 inches thick, as
measured horizontally from the wall. A perforated drain pipe should be placed at the base of the
drainage zone, as discussed below under Drainage Considerations.
Lateral earth pressures for design of below-grade walls and retaining structures should be
evaluated using an equivalent fluid density of 35 pounds per cubic foot (pcf). This value assumes
the adjacent ground surface is level, the backfill is compacted, as recommended below, behind
the wall and that the wall is free to rotate outrvard at the top. If the ground surface behind the
wall is sloped at an inclination steeper than 3H:lV, an equivalent fluid density of 50 pcf should
be used to determine design lateral pressures. If surface loads such as parking areas are located
close to the walls (a distance of less than one half the lvall height) additional surcharge loads on
the walls should be considered.
Zones of lvall backfill not supporting structural elements should be compacted to between 90
and 92 percent of maximum dry density. Compaction to between 93 and 95 percent of maximum
dry density will be needed where the backfill supports structural elements such as slabs or
driveways. Heavy conrpaction equipment should not be operated within 5 feet of below-grade
walls or retaining structures to avoid overstressing the rvalls. Fland-operated equipment should be
used in this zone.
CeoEngineers Filc No. 7174-00140-l 130
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Madrona Medical Partners
January 15, 1999
Page 7
Lateral loads can be resisted by friction on the base of the footings and passive resistance on
the face of the footings or embedded portions of foundation elements. Frictional resistance
should be determined using a value of 0.35 for the coefficient of friction. Passive resistance
should be determined using an equivalent fluid density of 300 pcf, provided the footings are
either poured neat (i.e., rvithout forming) directly against undisturbed native soils or that granular
backfill placed adjacent to the footings is compacted to at least 95 percent maximum dry density
(per ASTM D-1557). The above values include a factor of safety of about 1.5.
FLOOR SLAB SUPPORT
The medium dense to very dense silty sand with gravel. encountered in our explorations, or
properly compacted structural fill, will provide satisfactory support for on-grade floor slabs. As
discussed above in the Subgrade Preparation section of this report, we recommend that the upper
one foot of the subgrade be compacted to at least 95 percent of ma,ximum dry density. A base
course layer of imported clean rvashed drain rock at least 6 inches thick should be placed to
provide unifornr support and form a capillary break beneath the slab.
We recommend that a vapor rctarder be installed bclow the floor slab to reduce the potential
for migration of moisture into slabs where moisture-scnsitive floor coverings will be used. This
vapor barrier may consist of a sheet of polyethylene overlain by 2 inches of fine to medium sand
with less thur 3 percent passing the No. 200 sieve.
We estimate that settlenrents of less than 2 inches will occur for the anticipated floor slab
Ioads (less than 75 psf). provided the floor slab is supported as recommended.
DRAINAGE CONSI DERATIONS
A permanent subsurface drainage system should be installed around the perimeter of the
clinic building. The subsurface drainage system should consist of 4-inch diameter, rigid,
perforated, smooth-walled polyvinyl chloride (PVC) drain pipe installed around the entire
foundation, and located at the base of the exterior wall footings. A subsur:face drainage system
should also be installed at the base of the drainage zone behind all retaining walls. The drain pipe
should be surrounded by at least a 6-inch thickness of clean (less than 3 percent passing the
No. 200 sieve) medium to coarse sand with fine gravel. This 6-inch thickness of sand and gravel
should be enclosed in a geote,rtile intended for drainage purposes to prevent the migration of soil
into the perforated drain pipe. The drain pipe should be connected by a non-perforated tightline
system sloped to drain to an appropriate disposal point.
Permanent drainage systems should intercept surface water runoffat the top and./or bottom of
cut and fill slopes to prevent it from flolving in and uncontrolled manner across the site. The
finished ground surface adjacent to building should be sloped so that surface water runoff flows
away from the structure. Roof drains should be tightlined to an appropriate discharge point and
should not be connected to the footing or wall drains.
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GeoEngineers File No. 7174-001-00-1 130
Madrona Medical Partners
January 15, 1999
Page 8
LIMITATIONS
We have prepared this report for use by Madrona Health Partners and Rigby Architects for
development of the site as proposed. Our report should be provided to prospective contractors for
bidding purposes, but our conclusions and interpretations should not be construed as a warranfy
of the subsurface conditions.
The project was in the design development stage at the time this report was prepared. We
expect that further consultation regarding specific design elements will be necessary. When the
design has been finalized, \ve recommend that GeoEngineers be retained to review the final
design drawings and specifications to see that our recommendations have been interpreted and
implemented as intended.
Our scope does not include services related to construction safety precautions and our
recommendations are not intended to direct the contractor's methods, techniques, sequences or
procedures, except as specifically described in our report for consideration in design.
There are possible variations in subsurface conditions between the locations of explorations.
Variations may also occur with tinre. A contingency for unanticipated conditions should
therefore be included in the project budget and schedule. Sufficient monitoring, testing and
consultation should be provided by our firnr during construction to confirm that the conditions
encountered are consistent with those indicated by the explorations, to provide recommendations
for design changes should the conditions revealed during the work differ from those anticipated,
and to evaluate whether or not earthwork and foundation installation activities comply with the
contract plans and specifications.
Within the limitations of scope, schcdule and budget, our services have been executed in
accordance with generally accepted practiccs in this area at the time the report w:rs prepared. No
other conditions, express or implied, should be understood.
We appreciate the opportunity to be of service to you. If you have any questions concerning
this report or if we can providc services, please call.
Respectfu I ly submitted,
P.E.
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P:\7001o799\7 I 7400 I \00\Finals\7 t7 400 l0O Reporr.doc
Attachments
Three copies submitted
26693
EXPIFES
GeoEngineers File No. 717.t-001{0-l 130
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EXPLANATION
Note: 1. The locotions of oll feotures2. Dotum is qssumed.
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Reference: Survey entiUed "Lots 1 -4 &Jefferson County, Woshington
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SITE PLAN
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MAJOR DIVISIONS
GROUP
SYMBOL GROUP NAME
COARSE
GRAINED
SOILS
More Than
50% Ratained
on No. 200
Sieve
GRAVEL
More Than 50%
of Coarse Fraction
Retained on
No. 4 Sieve
CLEAN GRAVEL GW WELL€RAOEO GRAVEL. FINE TO COARSE GRAVEL
GP POORLY€RADED GRAVEL
GRAVEL WITH
FINES
GM SILTY GRAVEL
GC CLAYEY GRAVEL
SAND
More Than 50% of
Coarse Fraction
Passes No. 4 Sieve
CLEAN SAND SW WELL.GRAOED SAND, FINE TO COARSE SAND
SP POORLY€RADED SAND
SANO WITH
FINES
SM SILry SANO
sc CLAYEY SAND
FINE
GRAINEO
sotLs
More Than
50% Passes
No. 200 Sieve
SILT AND CLAY
Liquid Limit
Less Than 50
INORGANIC
ML SILT
CL CLAY
ORGANIC OL ORGANIC SILT, ORGANIC CLAY
SILT ANO CLAY
Liquid Limit
50 or More
INORGANIC
MH SILT OF HIGH PLASTICITY. ELASTIC SILT
CH CLAY OF HIGH PLASTICIry, FAT CLAY
ORGANIC OH ORGANIC CLAY, ORGANIC SILT
HIGHLY ORGANIC SOILS PT PEAT
SOIL CLASSIFICATION SYSTEM
NOTES SOIL MOISTU RE MODIFIERS:
Dry - Absence of moisture, dusty, dry to the touchField classification is based on visual examination of soil
in general accordance with ASTM D2488-9O.
2.Soil classilication using laboratory tests is based on
ASTM 02487-90.
Moist - Oamp, but no visible water
3. Descriptions ofsoil density or consistency are based on
intorpretation of blow count data, visual appearance of
soils, and/or test data.
Wet Visible free watet or saturated, usually soil is obtained
ftom below water table
Geo SflEngineers
SOIL CLASSIFICATION SYSTEM
FIGURE 3
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DEPTH BELOW
GROUND SURFACE
(feetlt
SOIL GROUP
CLASSIFICATION
SYMBOL DESCRIPTION
0.0 - 0.5
0.5 - 2.0
SM
SM
SM
TEST PIT 1
Approximate surface elevation: 196 feet
Dark brown silty sand with roots floose, moist) (topsoil)
Brown silty fine sand with occasional gravel (medium dense,
moist)
Grades to
Light brown silty fine to medium sand with gravel and
occasional cobbles (dense, dry)
Test pit completed at 7.0 feet below ground surface on
t2/23198
No ground water seepage observed.
No caving observed.
Disturbed soil sample obtained at 3.5 feet.
2.0 - 7.0
0.0 - 0.25
0.25 - 6.0
SM
SM
TEST PIT 2
Approximate surf'ace elevation: 199 f'eet
Dark brown silty sand (loose, moist) (topsoil)
Brown silty fine to medium sand with gravel (dense, dry-
moist)
Grades to very dense at 5.0 feet
Test pit complete<l at 6.0 feet below grouncl surface on
12123198 due to practical refusal
No ground water seepage observed.
No caving observed.
THE DEPTHS ON THE TEST PIT LOGS. ALTHOUGH SHOWN TO O.I FOOT, ARE BA.SED ON AN AVERAGE OF
MEASTJREMENTS ACROSS THE TEST PTT AND SHOULD BE CONSIDERED ACCURATE TO O'5 FOOT.
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LOG OF TEST PITS
FIGURE 4
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DEPTH BELOW
GROUND SURFACE
(feet)r
0.0 - 0.75
0.75 - 1.0
1.0 - 5.5
0.0 - 0.5
0.5 - 2.0
2.0 - 6.0
SOIL GROUP
CLASSIFICATION
SYMBOL
THE DEPTI{S ON THE TEST PIT LOGS. ALTHOUGH SHOWN
MEASI'REMENTS ACROSS THE TEST PIT AND SHOULD BE CONSID
LOG OF TEST PITS
DESCRIPTION
Approx imate surface ;T::;r' r*,
Dark brown silty fine sand with roots (loose, moist)
(topsoil)
Red brown silty fine sand with occasional gravel (medium
dense, moist)
Light brown silty trne to medium sand with gravel (dense,
dry-moist)
Grades to very dense at 3'0 feet
Test pit completed at 5.5 f'eet below grouncl surface on
1212'3/98 due to practical refusal
No ground water seepage observed.
No caving observed.
Disturbed soil sample obtained at 4.0 feet.
TEST PIT 4
Approximate surface elevation: 202 feet
Dark hrown silty finc sancl with roots (loose, moist)
(topsoil)
Brown silty fine sand to silty gravel (medium dense, moist)
Light brown silty fine to medium sand with gravel (dense,
dry-moist)
Grartes to very dense at 3.5 feet
Test pit completed at 6.0 f'eet below ground surface on
12123198 due to practical refusal
No ground water seepage observed.
No caving observed.
Disturbed soil sample obtained at 1.5 feet.
TO O.I FOOT, ARE BASED ON AN AVERAGE OF
ERED ACCURATE TO 0.5 FOOT.
SM
SM
SM
SM
SM/GM
SM
LOG OF TEST PITS
FIGURE 5#z EngineersGeo
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DEPTH BELOW
GROUND SURFACE
(feetll
SOIL GROUP
CLASSIFICATION
SYMBOL DESCRIPTION
0.0 - 0.5
0.5 - 2.5
SM
SM
SM
TEST PIT 5
Approximate surface elevation: 196 feet
Dark brown silty fine sand with roots (loose, moist) (topsoil)
Brown silty line to medium sand with occasional gravel
(medium dense, moist)
Light brown silty fine to medium sand with gravel (dense,
dry-moist)
Grades to very dense at 4.0 feet
Test pit completed at 6.5 feet below ground surface on
12123198 due to practical refusal
No ground water seepage observed.
No caving observed.
2.5 - 6.5
I THE DEFTHS ON THE TEST PIT LOGS. ALTHOUGH
MEASUREMENTS ACROSS THETEST PIT AND SHOULD BE
SHOWN TO O.I FOOT, ARE BASED ON AN AVERAGE OF
CONSIDERED ACCURATETO 0,5 FOOT.
Engineers
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LOG OF TEST PITS
FIGURE 6
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MOISTURE CONTENT DATA
* Refer to test pit logs for colnplete soil description.
Test Pit
Number
Depth of
Sample (feet)
Soil
Gtassification'
Moisture
Content (%)
I
J
4
4
4
1.5
SM
SM
GM
4
'7
6
RE CONTENT DATAMOISTU
FIGURE 7
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