BELC2014-1058 Preliminary Geotechnical InvestigationPRELIMINARY GEOTECHNICAL INVESTIGATION
FOUR RESIDENTIAL LOTS
NORTH OF AVENUE 58
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WEST OF MADISON'STREET
LA QUINTA, CALIFORNIA
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PRELIMINARY GEOTECHNICAL INVESTIGATION
FOUR RESIDENTIAL LOTS
NORTH OF AVENUE 58 &.WEST OF MADISON STREET
LA QUINTA, CALIFORNIA
Prepared for:
La Quinta Construction
78435 Hwy. 1 1 1, Suite C
La Quinta, CA 92253
Attn: Mr. Toby Lee
Prepared by:
.Southland Geotechnical, Inc.
79-607 Country Club Drive, Suite 5
Bermuda Dunes, California 92201
Report No. P00004
February, 2000
OUTWL4ND-
EOTE `PNIC4L=
March 6, 2000
La Quinta Construction
78435 Hwy. 111, Suite C
La Quinta, CA 92253
Attn: Mr. Toby Lee
Dear Mr. Lee:
FOUNDATION ENGINEERS AND MATERIALS
Preliminary Geotechnical Investigation
Four Residential Lots
North of Avenue 58 & West of Madison Street
La Quinta, California
SGI Report No. P00004
Southland Geotechnical, Inc. is pleased to submit this Geotechnical Report for the
proposed four residential lots to be located north of Avenue 58 and west of Madison
Street in La Quinta, California. Our geotechnical investigation was conducted in
response to your request for our services. The enclosed report describes the
investigation conducted and presents our professional opinions and recommendations
for geotechnical aspects of design and construction of the nro;ect
From a geotechnical engineering perspective, it is our opinion that the site is suitable
for the proposed development provided the recommendations contained in this report
are implemented in the design and construction of the project.
We appreciate the opportunity to provide our professional services. If you have any
question or comments regarding our findings, please call our office at (760) 360-0665.
Respectfully Submitted,
Southland Geotechnical, Inc.
Joseph R. Sidor, GE
Senior Geotechnical Engineer
Dist: (5) Addressee
Karl A. Harmon
Staff Geologist
780 NORTH FOURTH STREET - EL CENTRO. CALIFORNIA 92243 - (760) 370-3000
79-607 COUNTRY CLUB DRIVE, SUITE 5 - BERMUDA DUNES, CALIFORNIA 92201 - (760) 360-0665
5725 KEARNY VILLA ROAD. SUITE L - SAN DIEGO, CALIFORNIA 92123•• (619) 467-4900
TABLE OF CONTENTS
Page
Section 1 INTRODUCTION ................................ 1
1.1 Proposed Development ............................ 1
1.2 Purpose and .Scope of Work ........................ 1
1.3 Authorization ................................... 1
Section 2 METHODS OF INVESTIGATION ...................... 2
2.1
Field Exploration ................................ 2
2.2
Laboratory Testing ............................. 3
Section 3
FINDINGS ..................................... 4
3.1
Site Description ................................. 4
3.2
Subsurface Conditions ............................ 4
Section 4 CONCLUSIONS ................................. 6
4.1
General Conclusions ..............................
6
4.2
Specific Conclusions .............................
6
Section 5
RECOMMENDATIONS .............................
7
5.1
Site Preparation .................................
7
5.2
Removals .....................................
7
5.3
Subexcavation & Pre -wetting .......................
8
5.4
Temporary Excavations ............................
8
5.5
Compacted Fills .................................
8 ,
5.6
Trench and Structure Backfill ........................
9
5.7
Foundation Design ...............................
9
5.8
Slabs -On -Grade ..................................
10
5.9
Retaining Walls ..............:..................
10
5.10
Slopes .......................................
11
5.11
Soil Corrosivity.................................
11
5.12
Pavements ....................................
12
5.13
Seismic Design Criteria ............................
13
Section 6 LIMITATIONS AND ADDITIONAL SERVICES ............. 14
6.1 Limitations .................................... 14
6.2 Additional Services ............................... 15
EXHIBITS
Plate
VicinityMap ........................................ 1
Site and Exploration Plan ............................... 2
Subsurface Logs ..................................... 3-7
Keyto Logs ............................. 8
Laboratory Test Results ..........................:..... 9-12
Four Residential Lots -La Quinta, CA SGI Project No.: P00004
Section 1
INTRODUCTION
1.1 Proposed Development
It is understood that the four lots are being planned for development of single family
residential structures. The structures will be one or two story, wood framed
construction with concrete slabs -on -grade. No grading plan was available at the time
of our investigation.- Based on site topography, it is also expected that design grading
will include cuts and fills to maximum depths of approximately 10 feet.
1.2 Purpose and Scope of Work
The purpose of our study was to prepare this geotechnical report containing our
findings and preliminary conclusions and recommendations for grading and design.
Our scope of work included the following tasks:
• Drill, log and sample five exploratory borings.
• Perform laboratory tests of soil samples obtained from the borings.
• Review pertinent geotechnical literature and publications with -respect to local
seismicity, faulting, groundwater and liquefaction.
• Evaluate the field, laboratory and literature data and prepare this Geotechnical
Investigation report.
1.3 Authorization
Authorization to proceed with this study was provided by written. agreement in
accordance with our proposal for professional services dated September 29, 1999.
Southland Geotechnical, Inc. Page 1
Four Residential Lots -La Quinta, CA SGI Project No.: P00004
Section 2
METHODS OF INVESTIGATION
2.1 Field Exploration
Our field exploration consisted of drilling five, 8 -inch diameter borings to depths
ranging from approximately 11 to 16 feet. The borings were drilled on February 10,
2000 using truck -mounted hollow stem auger drilling equipment. All borings were
backfilled with the excavated cuttings after completion of the drilling program. The
locations of the borings are shown on the Site and Exploration Plan, Plate 2. Boring
locations were established by paced or taped measurements relative to existing
landmarks and should be considered approximate.
Samples were retrieved using a 3 -inch O.D. split -spoon sampler or a 2 -inch O.D.
Standard Penetration Test (SPT) sampler. The samples were retrieved by driving the
sampler ahead of the auger tip at selected intervals. The rig was equipped with a 140 -
pound CME automatic hammer for conducting Standard Penetration Tests (SPT)
(ASTM D 1586). The number of blows required to drive the samplers into the soil were
o t e
logs is presented on Plate 8. The blow counts presented on the Boring logs have not
been- corrected for the effects of borehole diameter, over burden pressure, sampler
diameter or other factors.
A staff geologist observed and logged the borings during the field explorations. The
logs were -edited in final form after an examination of the retrieved samples and review
of the field and laboratory data.
The soils encountered were classified in accordance with the Unified Soil Classification
System. The stratification lines shown on the subsurface logs represent the
approximate boundaries between the various strata at the boring locations. However,
the transition from one stratum to another may be gradual.
Southland Geotechnical, Inc. Page 2
Four Residential Lots -La Quinta, CA SGl Proiect No.: P00004
2.2 Laboratory Testing
Laboratory tests were conducted on selected soil samples to aid in the classification
and evaluation of the physical characteristics and engineering properties of the soils.
The tests were conducted in general compliance with the procedures of the American
Society for Testing and Materials (ASTM) or other standardised methods. The
laboratory testing program consisted of the following tests:
• Moisture Content and Unit Dry Density
• Corrosivity Potential
• Hydrocollapse Potential
The laboratory test results are presented on the boring logs and on Plates 9 through
12 in the Exhibits sections of this report.
Southland Geotechnical, Inc. Page 3
Four Residential Lots -La Quinta, CA SG1 Project No.: P00004
Section 3
FINDINGS
3.1 Site Description
The project site consists of a square, ten acre parcel (APN 760-090-021 & 022)
located south of the PGA West Country Club in La Quinta, California.. Topography on
the site is irregular with total relief of 10 to 15 feet. While some vegetation in the
southern portion of the site has recently been removed, the majority ' of the site is
covered by a relatively dense growth of native brush, weeds and trees. The site is
bordered on the east by an existing ranch, the south by Avenue 58, vacant land to the
west and an existing block wall and the PGA West Country Club to the north.
3.2 Subsurface Conditions
Data from our investigation indicate that the site soils consist of loose to medium
dense, dry to slightly moist sand and silty sand (SP and SP -SM) and interbedded with
lenses of silt(ML). In-place dry densities of soil samples were found to vary from 98
to 106 pounds per cubic foot. The results of corrosivity testing indicated low soluble
sulfate content, moderate chloride content and low electrical resistivity. The results
of the corrosivity tests are shown on Plate 12.
In arid climactic regions granular soil have a potential to collapse upon wetting.
Hydrocollapse could be caused by landscape irrigatiori, rainfall runoff, and leaking or
broken utility lines. Hydrocollapse is commonly mitigated by removing the sensitive
soil beneath the proposed structures. Standard geotechnical engineering practice in
this area is to test for collapse potential that may result in immediate settlement of the
soil upon wetting. Collapse potential testing on selected soil samples (see Plates 7,8
and 9) indicates 0.4% to 4.2°x6 collapse upon inundation. This amount of collapse
potential is considered a slight to moderate risk for the proposed structures.
Southland Geotechnical, Inc. Page 4
Four Residential Lots -La Quinta, CA SGi Project No.: P00004
No groundwater was encountered in any of the exploratory borings to the maximum
depths attained at 16.5 feet. Based on information obtained from the Coachella Valley
Water District, water level monitoring of a well located approximately '/2 mile to the
north-northwest indicates groundwater at a depth greater, than 100 feet.
Southland Geotechnical, Inc. Page 5
Four Residential Lots -La Quinta, CA SGI Project No.: P00004
Section 4
CONCLUSIONS
4.1 .General Conclusion
Based on the results of our investigation, it is our opinion that the proposed
development is geotechnically feasible and that the impact of the constraints discussed
in this study can be suitably mitigated.
4.2 Specific Conclusions
• The site soils, in their present condition, are relatively loose and variable
in density and subexcavation and replacement as compacted fill will be
necessary to provide a more uniform, less compressible and higher
strength soil subgrade for support of the proposed structures.
• The site soils exhibit a slight to moderate potential for collapse when
inundated. The effects of hydrocollapse can be mitigated by
subexcavation and compaction during grading. .
• The potential for soil liquefaction at the site is considered low due to the
absence of shallow groundwater.
Southland Geotechnical, Inc. Page 6
-La Quinta, CA
Four Residential Lots SGI Project No
Section 5
RECOMMENDATIONS
5.1 Site Preparation
All debris or vegetation such as grass, shrubs, trees or weeds should be removed from
the construction area. Any root balls should be completely excavated. Organic
strippings should be hauled from the site and not be incorporated into any engineered
fills. All trash, construction debris, concrete slabs, old pavements, landfill and buried
obstructions (such as old foundations, septic tanks, seepage pits, wells, and utility
lines) should be located by the grading contractor and removed under the observation
of the geotechnical engineer. Any excavations resulting from site preparation should
be dish -shaped to the lowest depth of disturbance and backfilled with engineered fill
as described in Section 5.4.
5.2 Removals
The upper existing soils, because of their variable density and moderate potential for
hydrocollapse, are considered unsuitable in their present state for support of the
structures, pavements and hardscape. Removals in the building pad areas should be
.made to a minimum depth of three feet below the existing surface and to at least five
feet laterally beyond the structure' perimeter: Removals in the. pavement and
hardscape areas should be made to a minimum depth of two feet below the existing:
` surface: Removals will also assist in locating buried man-made features, including non-
engineered,fill, that will also require removal. Actual depths and extent of removals
should be determined by the soil engineer during grading. Removed soil, free of
concentration of vegetation or other deleterious materials, may be used as compacted
fill.
Southland Geotechnical, Inc. Page 7
Four Residential Lots -La auinta, CA SGI Project No.: P00004
5.3 Subexcavation & Pre -wetting
In addition to the removal recommendations described in Section 5.2, building areas
should be subexcavated to a minimum depth of three feet below footing base elevation
and to at least five feet laterally beyond the building perimeter.
To reduce the potential for soil hydrocollapse, all structures should be underlain with
soil that has been moistened to near optimum moisture content to a minimum distance
of six feet below footing base elevation. This may be accomplished by flooding,
sprinkling or with moisture conditioned, compacted fill.
5.4 Temporary Excavations
Temporary excavations for footing and utility excavations less than about three feet
deep in moistened native soils may stand nearly vertical for short duration. Dry "or
excavations deeper than about three feet should be sloped no steeper than 1:1
(horizonta1:vertical). Soil slopes should be kept moist, but not saturated, to reduce the
potential of raveling or sloughing Any excavations over 5 feet in depth will require
shoring or slope inclinations in conformance to CAL/OSHA standards for Type C soil.
Surcharge loads of stockpiled soils or construction materials should be set back from
the top of. the slope a minimum distance equal to the height of the slope.
5.5 Compacted Fills
After site preparation, removals and subexcavation and prior to placing fill, the ground
surface should be scarified to a depth of 12 inches, moisture conditioned to near
optimum and compacted to 90 percent or more of the maximum dry density, as
determined by ASTM D1557.
On site soils should serve as suitable material provided they are free of concentrations
of organic matter or other deleterious materials. All imported fill soils (if required)
Southland Geotechnical, Inc. Page 8
Four Residential Lots -La Quinta, CA SGI Project No.: PO
should be non -expansive, granular soils meeting the USCS classifications of SM, SP,
or SW with a maximum rock size of 3 inches and 5 to 20% passing the No. 200 sieve.
Imported fill soils should be approved by the soils engineer before hauling to the site.
Fill should be placed in lifts no greater than 8 inches in loose thickness and compacted
at optimum moisture +/- 2% to a minimum of 90% of ASTM D1557 maximum dry
density in the building pads and to a minimum of 90% in all other areas.
All site preparation and fill placement should be observed and tested by a
representative of a qualified geotechnical engineering firm. This is emphasized during
the excavation and scarification process to detect any undesirable materials or
conditions such as soft areas or artificial fills that may be encountered in the
construction area.
5.6 Trench and Structure Backfill
Backfill soils should be placed in layers not more than eight inches in thickness and
compacted to 90 percent of the maximum density obtainable by the ASTM
Designation D1557 method of compaction. The soils encountered in the excavations
will be suitable for use as trench backfill. Precautions should be taken in the
compacting of the backfill to avoid damage to the pipes and structures. The moist
density of the compacted backfill may be assumed to be 120 pounds per cubic foot
for design considerations.
5.7 Foundation Design
The proposed structures may be supported on continuous and/or isolated spread
footings founded at least 18 inches below the lowest adjacent final grade and having .
P minimum width .of 12. inches for wall footings and 30 inches for column footings.
Footings for buildings and retaining walls may be designed for an allowable soil bearing
pressure of 2000 pounds per square foot. This bearing value may be increased by one-
third for wind and seismic loading.
Southland Geotechnical, Inc. Page 9
�. Four Residential Lots -La Quinta, CA SGI Project No.: P00004
The minimum steel reinforcement for foundations should be determined by the
structural engineer.
An allowable passive earth pressure value of 250 pounds per square foot per foot of
depth may be used for the sides of footings. The top 18 -inches of embedment should
not be considered in computing passive resistance unless the adjacent area is confined
by a slab or pavement. A friction coefficient of 0.35 may be assumed between the
soil and concrete. Passive pressure and friction values may be combined without
reduction.
Planters adjacent to the buildings should be avoided as much as possible unless they
are leak -proofed or lined and landscape water is designed to drain away from the
buildings (positive drainage).
5.8 Stabs -On -Grade
Concrete slabs -on -grade and independent flatwork (sidewalks and patios) should be a
minimum of 4 -inches thick and bear on a minimum of 12 incheG of compacted fill
Floor slabs to receive moisture sensitive floor coverings should be underlain by a 2 -inch
minimum thickness sand base and a plastic membrane of at least 10 mil thickness.
Slab thickness and reinforcement requirements should be as specified by the structural
engineer.
5.9 Retatning Walls
Retaining walls should be designed to resist the soil pressure imposed by the
surrounding soil mass. Walls which are unrestrained at the top and have level and well
drained backfiil may be designed for an assumed earth pressure equivalent to that
exerted by a fluid weighing not less than 35 pounds per cubic foot for existing site
soils.
Southland Geotechnical, Inc. Page 10
Four Residential Lots -La Quinta, CA SGi Project No.: P00004
Any applicable construction and seismic surcharges should be added to the above
pressures. If imported soil, sloping backfill or restrained walls are proposed, the soil
engineer should be contacted to develop applicable lateral pressure parameters. At
least twelve inches in width of granular material with a sand equivalent of 30 or
greater should be used for the backfill behind the walls. Water pressure should be
prevented from build-up behind retaining walls by employment of slotted weep holes,
outlet drain pipes through the walls, or any approved back -drain system. The upper
eighteen inches of retaining wall backfill should consist of relatively impervious
compacted soil.
5.10 Slopes
Slopes should be constructed generally no steeper than 3(H):1(V) to permit easy
landscape maintenance and provide erosional stability from wind or rain while
unprotected without landscape cover. Slopes with a 2(H):1(V) side slopes are
permitted provided it is recognized that such slopes are more prone to erosion and do
not permit landscape maintenance by motorized riding equipment, and require
landscape cover to retard erosion.
5.11 Soil Corrosivity
Sel_ected samples of soil from he site were chemically anaiyzed,andfiound to have low
concentrations of sulfates and moderate concentrations of chlorides. 7Cgnsequently,
concrete -in contact with native: soih may contain Type II or, Type V cement with e ;
maximum water/cement ratio of 0.50 (by weight): A minimum concrete cover of three
inches should be provided around steel reinforcement or embedded components
(anchor bolts, hold downs, etc.) exposed to native soil or landscape water to 18 inches
above grade. The above recommendations should be verified with sampling and
testing for soil corrosivity during grading when the- actual soils to be in contact with
concrete are exposed.
Southland Geotechnical, Inc. Page 11
Four Residential Lots -La Quinta, CA SGl Project No.: P00004
Resistivity tests of selected samples of native soil indicates a very severe potential for
metal loss due to electrochemical corrosion processes. Corrosion protection of steel
pipes can be achieved by using epoxy corrosion inhibitors or asphaltic coatings,
cathodic protection, or encapsulating with densely consolidated concrete. For
additional recommendations concerning protection due to the electrochemical corrosion
processes at the site, the services of a corrosivity engineer should be sought.
5.12 Pavements
Pavements may be designed according to CALTRANS or other acceptable methods.
Since no traffic loadings were provided, we have assumed traffic index for
comparative evaluation. Maintenance of proper drainage is necessary to prolong the
service life of the pavements. Based on the current State of California CALTRANS
methods, an estimated R -Value of 50 for the subgrade soil and assumed traffic index,
r- thefollowing table provides preliminary recommended pavement sections. The R -value
should be verified by sampling and testing during grading operations when the actual
subgrade soils will be exposed and the owner or design engineer should decide the
appropriate traffic index for the navementa
Southland Geotechnical, Inc. Page 12
Four Residential Lots -La Quinta, CA SGI Project No.: P00004
PRELIMINARY RECOMMENDED PAVEMENTS SECTIONS
Minimum R -Value Subgrade Soils - 50 (assumed)
Traffic
Flexible Pavements
Asphaltic
Aggregate
Index
Concrete
Base
(assumed)
Thickness
Thickness
(in.)
(in.)
15.0
[3.0
14:0
Notes:
1) Aggregate base should be Caltrans Class 2 (3/4 in. maximum), compacted to a minimum of
95% of ASTM D1557 maximum dry density.
2) All pavements should be placed on 6 inches of moisture conditioned, subgrade compacted to
a minimum of 95% of ASTM 131557 maximum dry density.
5.13 Seismic Design Criteria
This site is subject to moderate to strong ground shaking due to potential fault
movements along the San Andreas fault which is a Type A fault located at a distance
of 13 km. Engineered design and earthquake -resistant construction are the common
solutions to increased safety and development of seismic areas. Seismic design
factors using the 1997 edition of the Uniform Building Code are recommended as
follows:
Soil Profile Type: Sp
Near Source Factor Ne: 1.0
Near Source Factor NV: 1.1
Seismic Source Type: A
Southland Geotechnical, Inc. Page 13
Four Residential Lots -La Duinta, CA SGI Project No.: P00004
Section 6
LIMITATIONS AND ADDITIONAL SERVICES
6.1 Limitations
The recommendations and conclusions within this report are based on current
information regarding subject development. The conclusions and recommendations of
this report are invalid if:
► The structural loads change from those stated or the structures are
relocated.
► The Additional Services section of this report is not followed.
► This report is used for adjacent or other property.
> Changes of grade or groundwater occur between the issuance of this
report and construction other than those anticipated in this report.
► Any other change is implemented, which materially alters the project
We have based our findings and conclusions on selected points of field exploration,
laboratory testing, and our understanding of the proposed project. Our analysis of data
and the recommendations presented herein are based on the assumption that soil
conditions do not vary significantly from those found at specific exploratory locations.
However, it is possible that variations in soil conditions could exist between and
beyond the exploration points.or that groundwater elevations may change. These
conditions may require additional studies, consultation, and possible design revisions.
This report was prepared according to the generally accepted, geotechnical*engineering
standards of practice that existed in Riverside County at the time the report was
prepared. No warranty, expressed or implied, is made in connection with our services.
Southland Geotechnical, Inc. Page 14
Four Residential Lots -La Quinta, CA SGI Project No.: P00004
Because of potential changes in the Geotechnical Engineering Standards of Practice,
this report should be considered invalid after two years from the report date without
a review of the validity of the findings and recommendations by our firm.
The client has responsibility to see that all parties to the project including, designer,
contractor, subcontractor and future owners are made aware of this entire report.
6.2 Additional Services
The recommendations made in this report are based on the assumption that an
adequate program of tests and observations will be conducted during construction to
verify the field applicability of subsurface conditions and compliance of the
recommendations that are the basis of this report. Because of our experience and
familiarity with the project, we recommend that Southland Geotechnical be retained.
as the geotechnical consultant to provide the tests and observations. The geotechnical
engineering firm providing tests and observations should assume the responsibility of
geotechnical engineer of record.
These tests and observations should include, but not necessarily be limited to the
following:
► Observation and testing by the geotechnical consultant of record during
site clearing, grading, excavation, placement of fills, building pad and
subgrade preparation, and backfilling of utility trenches;
► Observation of foundation excavations and reinforcing steel before
concrete placement;
► Consultation as may be required during construction.
Southland Geotechnical, Inc. Page 15
Pour Residential Lots -La Quinta, CA SGI Project No.: P00004
In addition, we should review the project plans and specifications• to check for
compatibility with our recommendations and conclusions. Additional information
concerning the scope and cost of these services can be obtained from our office.
EJ
Southland Geotechnical, Inc. Page 16
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Project No: P00004 Site and Exploration Map
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2
CLIENT: Affordable Building Systems METHOD OF EXCAVATION: CME 55 W/ Autohammer
PROJECT: Four Residential Lofts DATE OSSERVED.2/10/00
LOCATION:See Site & Exploration Plan LOGGED BY: K. Harmon
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. CLIENT: Affordable Building Systems METHOD OF EXCAVATION: CME 55 W/Autohammer
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Plate
P00004
=
4
• CLIENT: Affordable Building Systems METHOD OF EXCAVATION: CME 55 W/Autohammer
PROJECT: Four Residential Lots DATE OBSERVED 2/10/00
LOCATION:See Site & Exploration Plan LOGGED BY: K. Harmon
LOG OF BORING B-3
zw
$
SHEET _1_ OF _1
it
.F.
2
W
Z
IL
d
DESCRIPTION OF MATERIAL
w ~
~
u
u
o
a.UJ
> C
oi
I@
o u
m
i
.
d
•:s;; s
:•{:tt{t
ti?tt; .t
2 .t_.s•,1
SAND (SP / SP-SM): Light gray, loose, dry, fine grained
:t
?t ?t ?t
3 ?t
•tt •tt-�5
•trL:t
• c ?t?t
SAND (SP-SM): Light olive-gray, medium dense,
4.3
105.
•,t:,s: t
27
slightly moist, fine to medium grained
ti?ti
:%:•ti= ti
'r= -
L•,t
r r.. •S
.r:r:•
{1?L?L
8 .tr:
9
•�
s?i
•;
r} r}.
t•,1
12
-Fine to very fine grained
: S • Sr2
12
%tt• t:.
•N",S•.t
?t: Lrr 1
3
13-
14
14
t::•
1
S=.LJ'l
44
-Dense, dry to slightly moist, fine grained
1.0
1041
:: Jr• t ti
rs
.
17 'L t
�r•:•s
::ti zi?i
18
?ti sr s
19 :{:srti
20
s
22
-Medium dense, silt lense @ 21.5 ft.
21 .,.t
End of Boring @ 21.5 ft.
j
I
j
No groundwater encountered
j
Project No:
Plate
ourHLAND
P00004
�_
CLIENT: Affordable Building Systems METHOD OF EXCAVATION: CME 55 W/ Autohammer
PROJECT: Four Residential Lots DATE OBSERVED 2/10/00
LOCATION:See Site & Exploration Plan LOGGED BY: K. Harmon
LOG OF BORING B-4
�
E
Z
0
c
SHEET _i_ OF _1
�
2
g
IL
IL
LL
0.
t
DESCRIPTION OF MATERIAL
d
e
Z
a
u
m
a
SURFACE ELEV. +1-
•tr?::.
:Lfsi 5:
Siti:s:J1
2
SAND (SP -SM): Olive, loose to medium dense,
slightly moist, fine grained
3
4
'1 I •• L-
•ti•:1r::
5
t. •. •
•t -t -L
23
2.0
101.
6
5 Vii•:,
:SSSt:.
7
Lts;•Lti
}:
9
.ti, ti al
iiiztt•
'
10
:i r,•Sr
11
.2-!
s:'•6tS
11
-Three inch silt layer @ 11 ft.
12
r°doi{
13
S:tt?i
14
r:irij.
ti. ryjt
T'ts'
15
it ri
•s:
r
:: it•
rL•t
21
-Medium dense, slightly moist to moist, fine grained
3.1
98.1
16
17
End of Boring @ 16.5 ft.
No groundwater encountered
1a
19-
9202122
20-
21-
22
Project No:
*HLANLU-)
Plate
P00004
IIC�-
6
. CLIENT: Affordable Building Systems METHOD OF EXCAVATION: CME 55 W/Autohammer
PROJECT: Four Residential Lots DATE OBSERVED 2/10/00
LOCATION:See Site & Exploration Plan LOGGED BY: K. Harmon
LOG OF BORING B-5
o
W
o
CLm
o
SHEET 1_ OF _1
m
x
o
ei
M
„
3
d
x
DESCRIPTION OF MATERIAL
d
5
7u
o;
t
x
CL
5
3
P,
m -A
o
a
SURFACE ELEV. +/-
0 o
u`
ix
c
a i;
a
o.
d
SANDY SILT/ SILTY.SAND (ML / SM): Olive, loose, 'moist
1
2-
3-
8
SANDY SILT (ML): Olive, medium dense, slightly moist
to moist, fine grained
4
5
25
SAND (SP-SM)): Olive, medium dense, slightly moist,
2.9
105.
=l ;Lr1
fine grained
7
r L LL
�L•�S?5
grit �1:
.•r•s:
•s•Ttia
SttS: 1L
t t :
�•tr•.'%•
10
-Slightly moist, fine to very fine grained
11
:S �StL•
••S ;1
12
113-No
groundwater encountered
14-
41817
16-
17-
119-
19202122Project
.20-
21-
22-
ProjectNo:
Plate
P00004
HLAND ,
*TECI•B�IICA
7
A.
200 4 10 4
US Standard Series Sieve
VeryLoose 0-4
Loose 4.10
Medium Dense 10-30
3!4' a 12"
Clear Square Openings
clays a Plastic Sms
StrertathBlovvsAt
DEF1NMON OF TERMS
PRIMARY OMSIONS
SYMBOLSI
SECONDARY OMSIONS
Soft
Gravelsp
a
GW
Well graded gravels, gravel -sand mbdums, little or no fines
4 8
8-16
Clean
2A -4A
16-32
Hard
T_
:•:
GP
Poody graded gravels, or gravel -sand mbdures, little or no fines
gravels Peas than
More than half
GM
Silty gravels, gravel -sand -silt mcdures, non -plastic fines
Coarse 9relo� sa
of coarse
fraction is Gravel
GC
Clayey gravels, gravel -sand -clay mbdures, plastic fines
More than half of
larger than wf h fines
Nm 4 sieve
Sands Clean sands (lessµ
SW
Well graded sands, gravelly sands. We or no fines
material is larger
.4 T_;,
SP
Poorly graded sands or gravelly sands, little or no fines
than No. 200 sieve
than 5% fines)
More than hall
SM
Silty sands, sand -slit mbdures, non-plastle tures
of coarse
fraction is Sands
("
[
Clayey sands, sand -clay mbdures, plastic fines
smaller than with finesSC
Slits and clays
ML
Inorganic silts, clayey sift wth slight plasticity
CL
Inorganic da • of low to medium plasticity,
r9 � P tY. 9+avelY. sandy, or lean days
Fine grained sols
Liquid ![mitis •
�I;IIOL
Organic sits and organic clays of low plasticity
More than half of
less than 50%
material is smaller
Silts and days
MH
Inorganic silts, micaceous or diatomaceous silly sails. elastic silts
CH
Inorganic clays of high plasticity, fat clays
than No. 200 sieve
Liquid limit is
more than 50%
OH
Organic clays of medium to high plasticity, organic sifts
Highly organic soils
r�Vtitry
PT
Peat and other highly organic sots
GRAIN SIZES
Silts and Clays
Sand
Gravel Cobbles
Boulders
Fine I Medium Coarse
I Fine Coarse
200 4 10 4
US Standard Series Sieve
VeryLoose 0-4
Loose 4.10
Medium Dense 10-30
3!4' a 12"
Clear Square Openings
clays a Plastic Sms
StrertathBlovvsAt
Very soft
0.0.25
0-2
Soft
02"S
24
Firm
CNN
0.S1.0
11.0 24
4 8
8-16
Very Stiff
2A -4A
16-32
Hard
Over 4.0
Over 32
Number of blows of 140 lb. hammer falling 30 Inches to drive a 2 Inch O.D. (13/8 in. ID.) split spoon (ASTM D1586).
'• Unconfined compressive sbengih In tonsts L as determined by laboratory testing or apprordmated by the Standard
Penetration Test (ASTM D1586), Pocket Penetrometer, Torvane, or visual observation.
Type of Samples:
Ring Sample Standard Penetration Test I ShelbyTube I* Bulk (Hag) Sample
Drilling Notes -
1. Sampling and Blow Counts
Ring Sampler - Number of blows per foot of a 140 lb. hammer falling 30 inches.
Standard Penetration Test - Number of blows per foot.
ShelbyTube - Three (3) inch nominal diameter tube hydraulically pushed.
Z P. P. - Pocket Penetrometer (tonsla.f.).
3. NR =No recovery.
4. GWiT a Ground Water Table observed @ specified time
ND
Plate
Project No: P00004 Key to Logs 8
M.
^,
COLLAPSE POTENTIAL TEST (ASTM D5333)
2
!
f
0
-1
iUVAter
-2
collapse
tentiai . '�ir(Slignt'
-3
r
l�
�-4
L
-5
-6ca
I
ani -7
I
a -8
s
-9
,
Silty Sand (SM)
-10 8-1 @ 15t
-12
i
-13
I
l
-14
.!
0.1- 1
*10
100
Pressure (ksQ
Results of Test:
Initial
Final
Dry Density, pef:
93.3
95.0
Water Content, %:
2.5
26.9
Void Ratio, e:
0.773
0.742
Saturation, %:
8.7
96.0
#M HL4ND
Wr
Collapse Potential
Plate
Project No: P00004
Test Results
9
gum
ue�
■� i
WON
MENEM
11111111111
Hill
0 1
Milli
Sand (SP -SM)
10110HIMEHIM111NI
I--_
COLLAPSE POTENTIAL TEST (ASTM D5333)
2
1
0
-1
-2
-3
-4
d
_ -5
c
tz
mc -6
U
c-7
a�
U
d
a _8
-9
-10 Sift (ML)
&5@2.58
I
Pressure (kso
'10
Results of Test:
Initial
Final
Dry Density, pcf:
65.9
100
Water Content, %:
26.1
Results of Test:
Initial
Final
Dry Density, pcf:
65.9
67.1
Water Content, %:
26.1
49.0
Void Ratio, e:
1.509
1.465
Saturation, %:
45.8
88.7
IHLAND _
TE�FaN�=
Project No: P00004
Collapse Potential
Test Results
Plate
1I
•
SOUTHLAND GEOTECHNICAL INC.
CLIENT: Affordable. Building Services
PROJECT: Fddt:Residential Lots
JOB NO: 'fl00004`
DATE: 02/18/00
--------------------------------------------
SOIL CHEMICAL ANALYSES
Boring: B-1
B-1
Sample Depth, ft: 1 to 4
0 to 2
pH: 7.9
8.3
Resistivity (ohm -cm): 380
225
Chloride (CI), ppm: 450
580
Sulfate (SO4), ppm: 235
580
Note: Tests performed by Soil & Plant Laboratory and Consultants
----------------
of Bermuda Dunes, CA under subcontract to our firm.
General Guidelines for Soil Corrosivity
Material Chemical Amount in
Degree of
Affected Agent Ad (Rpm or ohm -cm)
Corrosiv'
Concrete Soluble 0-1000
Low
Sulfates 1000-2000
Moderate
2000-5000
Severe
> 5000
Very Severe
Normal Soluble, 0-200
Low
Grade Chlorides 200-700
Moderate
-' Steel 700-1500
Severe
> 1500
Very Severe
' Normal . Resistivity 1-1000
Very Severe
Grade 1000-2000
Severe
Steel 2000-10,000
Moderate
10,000+
Low
NLAND .._
1ECI-O�IIC4.=
Selected Soil Chemical
Plate
Project No: P00004
Analyses Results
12