HomeMy WebLinkAbout; Broccato at Batiquitos Shores; As-Graded Geotechnical Report; 1996-11-07Geotechnics
Incorporated
November 7, 1996
Brookfield Davidson Homes
12865 Pointe Del Mar, Suite 200
San Diego, California 92014
Principals:
Anthony F. Belfast
Michael P. Imbriglio
W, Lee Vanderhurst
Project No. 0002-008-03
Document No, 6-0461
Attention: Mr. Dale Gleed
SUBJECT: AS-GRADED GEOTECHNICAL REPORT
Broccato at Batiquitos Shores
Carisbad, Califomia
Gentlemen:
This report summarizes the results of the observation and testing services provided during the
earthwork construction of the Broccato at Batiquitos Shores development. In our opinion, the
grading and compaction was performed in general accordance with the intent of the project
geotechnical recommendations and with the requirements of the City of Carisbad.
We appreciate this opportunity to provide professional services. If you have any questions or
comments regarding this report or the services provided, please do not hesitate to contact us.
Respectfully submitted,
GEOTECHNICS INCORPORATED
W. Lee Vanderhurst C.E.G.
Principal
DR/RAT/WLV/AFB
Distribution: (5) Addressee
9951 Business Park Ave., Ste. B • San Diego Califomia • 92131
Phone (619) 536-1000 • Fax (619) 536-8311
AS-GRADED GEOTECHNICAL REPORT
Broccato at Batiquitos Shores
Carisbad, Califomia
TABLE OF CONTENTS
1.0 INTRODUCTION
2.0 SCOPE OF SERVICES ^
3.0 SITE DESCRIPTION 2
4.0 PROPOSED DEVELOPMENT 2
5.0 GEOLOGIC CONDITIONS 3
5.1 Torrey Sandstone ^
5.2 Terrace Deposits ^
5.3 Alluvium ^
5.4 Colluvium ^
5.5 Documented Fill ^
5.6 Groundwater ^
5.7 Seismicity ^
6.0 SUMMARY OF GRADING OPERATIONS 5
6.1 Preparation of Existing Ground 5
6.2 Fill 6
6.3 Cut and Fill Slopes 6
6.4 Backdrains ®
7.0 LABORATORY TESTING 6
8.0 FIELD DENSITY TESTING 7
9.0 GEOTECHNICAL EVALUATION AND RECOMMENDATIONS 7
9.1 Fill Compaction ^
9.2 Slope Stability 8
9.3 Site Drainage ^
9.4 Settlement Monitoring ^
9.5 Foundations ''^
9.5.1 Post-Tensioned Slabs 10
9.5.2 Lateral Resistance
9.5.3 Slope Setback "t"*
9.5.4 Moisture Protection for Slabs 11
9.6 Exterior Slabs 11
9.7 Earth Retaining Structures 11
10.0 UMITATIONS 12
APPENDICES
Appendix A References
Appendix B Laboratory Testing
Appendix C Density Test Results
AS-GRADED GEOTECHNICAL REPORT
Broccato at Batiquitos Shores
Carisbad, Caiifomia
1.0 INTRODUCTION
This report summarizes the results of the testing and observation services provided during the
earthwork construction of Broccato at Batiquitos Shores. The purpose of the observation and
testing services was to evaluate the conformance of the earthwork construction with the
geotechnical recommendations and the project plans and specifications. Our services were
provided in accordance with our Proposal No. 6-126 (Geotechnics Incorporated, 1996a), and
Brookfield Davidson Homes' Contract No. A1410.
2.0 SCOPE OF SERVICES
Field personnel were provided for this project to observe the grading of the site and conduct field
density tests. The observation and testing assists us in developing professional opinions
regarding the earthwork construction. Our services did not include supervision or direction of the
actual work of the contractor, his employees, or agents. Our services included the following:
Laboratory testing to determine pertinent engineering characteristics of the soils used in
the fills and exposed at finished grade. The results are summarized in Appendix B.
Observation ofthe geologic conditions exposed during excavation and grading ofthe site.
On-site engineer/geologist was provided to evaluate slope stability conditions and provide
recommendations to improve slope stability. The geologic mapping is compiled on the
Geotechnica! Maps, Plates 1 through 4.
Observation and testing of fill placement during the site grading. Daily field reports were
prepared summarizing the observed earthwork operations. Test results are summarized
in Appendix C.
Installation of settlement monuments in areas where alluvium was not completely
removed, and monitoring and evaluation of the on-site settlement.
Geotechnics Incorporated
Brookfield Davidson Homes
Broccato at Batiquitos Shores
November 7, 1996
Project No. 0002-008-03
Document No, 6-0461
Page No. 2
Preparation of this report which summarizes our observations and test results, our
conclusions regarding the earthwork construction and site condilions, and
recommendations regarding foundation, slab, and pavement section design.
3.0 SITE DESCRIPTION
Broccato at Batiquitos Shores is located off of Baliquitos Drive in Carisbad, California as shown
on the Site Locaiion Map, Figure 1. The site encompasses roughly 40 acres on the north shore
of Batiquitos Lagoon. The site is bound by Baliquitos Lagoon and a sewer pump station to the
south, open space to the east and west, and by a residential neighborhood and Batiquitos Drive
to the north.
The site's topography originally consisted of a generally north-south trending drainage canyon with
moderately steep slopes to the east and west. Secondary drainages incised the slopes.
Elevations ranged from approximately 12 feet above mean sea level (MSL) at the southern end
of the site, to approximately 154 feet MSL at the northeastern comer of the site.
Existing improvements at the site included a paved access road to the lagoon and pump station,
a storm drain along the west side of the road, a force sewer main from the pump station, and a
water main and utility easement that crossed the site from east to west near the centra! portion
of the site. The northeastern part of the site also included some previously graded areas and a
large stockpile of soil.
4.0 PROPOSED DEVELOPMENT
The Broccato project will include the constnjction of 73 single-family homes along residential
streets, with open space along much ofthe perimeter. The pads are generally separated by short
retaining walls or slopes that are generally less than 10 feet high although slopes up to 30 feet
high also exist between parallel streets. Natural slopes and constructed slopes up to 30 feet high
border the east and west sides of the development.
ii
The project includes large areas of open space. The open space has been partitioned and given
lot numbers which are Lots 49, 50, 61, 62, and 77 through 81. The residential lots are numbered
1 through 48, 51 through 60, and 63 through 76.
Geotechnics Incorporated
Brookfield Davidson Homes
Broccato at Batiquitos Shores
November 7, 1996
Project No, 0002-008-03
Document No. 6-0461
Page No. 3
The improvements include the re-alignment of Batiquitos Drive and the construction of seven cul-
de-sacs, abandonment of an existing water line, and the construction of a storm drain system.
The cul-de-sacs are named Gabianno Lane, Cigno Court. Piovana Court, Merio Court, Grivetta
Court, and Anatra Court. A de-silting basin was to be constnjcted at the south end of the site;
however, this structure was not constructed at the time of this report. Development of the site
also included the construction of retaining walls between pads and in rear yards at the base of
slopes. The walls were generally less than 7 feet high.
5.0 GEOLOGIC CONDITIONS
The subject site is situated in the coastal plain section of the Peninsular Range Province, and is
primarily underiain by Cenozoic sedimentary bedrock materials and surficial deposits.
Specifically, the site is underiain by the Eocene-age Torrey Sandstone, Quaternary-age terrace
deposits, alluvial and colluvial soil, and compacted fill soil. The approximate as-graded geologic
conditions are depicted on the attached As-Graded Geotechnical Map, Plates 1 through 3.
5.1 Torrev Sandstone
As observed at the site, the Torrey Sandstone consisted of pale gray and yellow brown,
silty, fine- to medium-grained sandstone. In general, the sandstone was moderately
cemented and massive. Occasional concretions of strongly cemented material were
encountered.
The Torrey Sandstone was exposed at the base of the slopes along the western and
eastern sides of the site, and at finish grade in Lots 72 through 75. The Tortey Sandstone
likely underiies the entire site at depth.
5.2 Terrace Deposits
Terrace deposits were exposed in the upper portions of the slopes along the westem and
eastem sides of the site, and in the cut slope along the northeastem corner of the site.
As observed in the excavations, the terrace deposits consisted of orange-brown, clayey
fine- to medium-grained sandstone with some gravels at the base of the formation. The
sandstone was generally weakly to moderately cemented and massive.
Geotechnics Incorporated
m
m
m
Brookfield Davidson Homes ^^f^' No. 0002-008-03
Broccato at Batiquitos Shores Document No. 6-0461
November 7. 1996 ^. Page NO. A
5.3 Alluvium
Alluvial soils underiie much of the site. The alluvium was left in place where the
groundwater table made removal impractical. As observed by the grading, the alluvium
consisted of brown to dark brown, silty to slightly silty, fine to medium grain sand. The
alluvium was generally loose to medium dense.
5.4 Colluvium
Colluvial soils were exposed in the slopes sun-ounding the project. The colluvium
consisted of reddish brown, silty fine sand that was generally loose and dry. Colluvial
soils were removed from areas that were to receive fill and structura! loads.
5.5 Documented Fill
Documented fill was encountered in the northeastern portion of the site. Fil! was originally
placed under the observation and testing of ICG Incorporated in 1991 along the re-
alignment of Batiquitos Drive. More grading was performed in 1994 under the observation
of Geotechnics (1995). The materials used in the fill were derived primarily from
excavations in the property east of the Broccato project, and consisted primarily of silty
sand.
Stockpiled soil also existed at the site in the area of Lots 3 through 15. This material also
originated primarily from excavations east of the site. The stockpiled material was
removed and re-used as fill material during the finat grading of the subject site.
5.6 Groundwater
Groundwater was encountered during the removal of alluvial soils. The water table was
at an approximate elevation of 5 feet MSL at the southern end of the site, and at an
approximate elevation of 20 feet MSL near the intersection of Batiquitos Drive and
Gabbiano Lane. Groundwater seepage was also observed in the slope behind Lot 72 at
the contact between the underiying terrace deposit and the overiying colluvium.
Geotechnics Incorporated
0
Brookfield Davidson Homes
Broccato at Batiquitos Shores
November 7, 1996
Project No. 0002-008-03
Documenl No. 6-0461
Page No. 5
5.7 Seismicity
Several faults were observed in the Eocene-age sandstone during the grading ofthe site.
Theses faults, however, did not offset the overiying colluvium. and accordingly, are not
considered active. The active fault nearest to the site is the Rose Canyon fault located
approximately 2 miles to the west. A magnitude 6.5 earthquake on the Rose Canyon fault
could result in peak horizontal bedrock accelerations of approximately 0.48g.
6.0 SUMMARY OF GRADING OPERATIONS
In general, the earthwork consisted of the grading of the house pads, slopes, and street
subgrades. The site grades are shown on the Geotechnical Map. Plates 1 through 4. The
project grading plans, prepared by O'Day Consultants (1990). serve as base maps for the
Geotechnical Map.
Grading was performed by C.E. Wilson Corporation. Typical cut and fill mass grading techniques
were employed using heavy earth-moving equipment. Site grading began with the removal of
deleterious materials and loose surficial soils. Fill soils were placed to bring areas up to design
grades, and individual lots were graded.
6.1 Preparation of Existino Ground
The site was cleared of surface obstructions and stripped of vegetation. Existing loose
and unsaturated surficial soils were removed to expose competent bedrock materials, fill
soils placed during previous grading, or alluvial soils saturated by a standing water table.
Existing utilities that were to be abandoned, and the existing access road, were removed
and replaced with compacted fill. The stockpiled material previously placed on the site
was used in compacted fills.
Where transitions between bedrock and fill crossed building pads, the bedrock portion of
the lot was over-excavated approximately 3 feet deep, and brought back to planned grade
with compacted fill. Lots 65 and 71 were over-excavated to reduce the potential of
differential settlement due to cut/fill transitions.
Geotechnics Incorporated
m
Brookfield Davidson Homes ^'ojeci No. 0002-008-03
Broccato at Batiquitos Shores Document No. 6-0461
November 7, 1996 ^^9^ ^
The approximate limits of removals, and the approximate elevation of the bottom of the
removals, are indicated on the Geotechnica! Map. Prior to placing fill, the exposed
surfaces were scarified to a depth of 6 to 8 inches, brought to approximately optimum
moisture content, and compacted.
6.2 Fil!
Fil! soils for site grading were typically placed in 6- to 8-inch thick lifts, brought to
approximate optimum moisture content, and compacted by the equipment delivering,
watering, or mixing the soil. The equipment used for compaction consisted of rubber-tired
compactors, bulldozers, blades, water trucks, and scrapers.
6.3 Cut and Fill Slopes
Slopes up to 30 feet in height were constructed in general accordance with the project
plans and specifications at a slope ratio of 2:1 (horizontal to vertical). Much of the slopes
along the east and west sides of the site were over-excavated to remove exposed loose
surficial soils such as colluvium. The upper portion of the slope behind Lot 72 was also
over-excavated. The slopes were re-constructed with fill soils and backdrains to reduce
the potential for seepage through the slope faces, and to act as a buttress against the
loose colluvial soils. Fill slopes were back-rolled and track-walked at finished grade.
6.4 Backdrains
Backdrains were constructed beneath the buttressed slopes. The drains consisted of two-
sided filter fabric, approximately 6 feet in height, that were placed against the
over-excavated slope at an elevation approximately 2 feet below and 4 feet above the
finish toe of slope. The fabric was wrapped around perforated PVC pipes which were
connected to the on-site storm drain system. However, the subdrains on Lot 72 and at
the desilting basin were not tied-in to an outlet at the time of this report.
7.0 LABORATORY TESTING
The various materials used as fill are described in Figure B-1 of Appendix B. "Laboratory Testing".
The maximum density and optimum moisture content of the soil types used as fill were
Geotechnics Incorporated
1
p Brookfield Davidson Homes
Broccato at Batiquitos Shores
November 7. 1996
Project No, 0002-008-03
Documenl No. 6-0461
Page No. 7
determined in the laboratory by ASTM method D1557-91 (Modified Proctor). The fills generally
consisted of fine- to medium-grained sand, silty sand, and clayey sand.
To evaluate materials for conformance with project specifications, expansion index testing was
conducted on representative samples collected from the finish-graded pads. ASTM test method
D4829 was used to evaluate the expansion index. The results ofthe expansion index testing are
presented on Figure B-2 of Appendix B. The results of the tests indicate expansion potentials
ranging from very low to medium.
8.0 FIELD DENSITY TESTING
In-place moisture and density tests were made in accordance with ASTM D2922-91 and D3017-
88 (Nuclear Gauge Method). The results of the tests conducted during this phase of mass
grading of Broccato are tabulated in Figures C-1 through C-12 of Appendix C, "Field Density Test
Results". Appendix C presents the relative compaction of the fill as compared to the respective
maximum density (ASTM Dl 557-91). The density testing conducted on the previously
documented fills is presented in the referenced reports (ICG, 1991; Geotechnics, 1995).
The locations and elevations indicated for the tests presented on the Geotechnical Map are based
on field survey stakes and estimates from the grading plan topography, and should only be
considered rough estimates. The estimated locations and elevations should not be utilized for
the purpose of preparing cross sections showing test locations, or in any case, for the purpose
of after-the-fact evaluating of the sequence of fill placement.
9.0 GEOTECHNICAL EVALUATION AND RECOMMENDATIONS
In our opinion, grading and compaction was performed in general accordance with the intent of
the project geotechnical recommendations (San Diego Soils Engineering, 1986), and with the
requirements of the City of Carisbad. The conclusions and recommendations contained herein
are based on the observations and testing perfonned between June 25. 1996. and October 28.
1996. No representations are made as to the quality and extent of materials not observed.
9.1 Fill Compaction
Geotechnics Incorporated
ip
m
Brookfield Davidson Homes Project No. 0002-008-03
Broccato al Batiquitos Shores Document No. 6-0461
November 7, 1996 Page No. 8
Based upon our observations and testing, it is our professional opinion that fill soils were
placed in accordance with the compaction criteria of 90 percent of the maximum density
as determined by ASTM D1557-91. Where field testing indicated less than 90 percent
relative compaction, the pertinent fill soils were reworked to achieve the specified
compaction.
9.2 Slope Stabilitv
Fill and cut slopes were constructed to heights up to 30 feet. Slope stability was
evaluated based on the referenced geotechnical investigation (San Diego Soils
Engineering, 1986), and site observations of conditions exposed during grading.
In general, slopes should be stable with regard to deep-seated failure with a factor of
safety of at least 1.5. Slope analysis was based on our best estimate of the prevailing
geologic conditions, groundwater conditions and soil strength characteristics. It should be
realized that site conditions can be complex and variable due to changes in stratigraphy,
geologic structure, and changes in groundwater. It is possible that conditions can differ
from those anticipated in our analysis. In addition, cuts or retaining walls constructed at
the toe of slopes could decrease slope stability. Any changes to constructed slope
heights, ratios, retaining walls, or addition of surcharge should be evaluated by the
geotechnical consultant.
Man-made and natural slopes will weather over time as a result of wetting and drying,
biologic forces and gravity. As a result, the outer 5 feet of slope face may undergo minor
down-slope creep over the years. While it is not possible to completely eliminate this
effect, it can be minimized by establishing deep-rooted vegetation on the slope,
maintaining the drainage pattems established during construction, and by rodent control.
We recommend vegetation which is adapted to semi-arid climates, therefore requiring
minimal irrigation.
9.3 Site Drainage
Foundation and slab performance depends greatly on how well the runoff waters drain
from the site. This is true both during construction and over the entire life of the structure.
The ground surface around structures should be graded so that water flows rapidly away
from the structures without ponding. The surface gradient needed to achieve this depends
Geotechnics Incorporated
• Brookfield Davidson Homes P^^^cl No. 0002-008-03
Broccato at Batiquitos Shores Document No. 6-0461
November 7. 1996 ^^^^ ^
on the prevailing landscape. In general, we recommend that pavement and lawn areas
within five feet of buildings slope away at gradients of at least two percent. Densely
vegetated areas should have minimum gradients of at least five percent away from
buildings within five feet of the structure's perimeter. Densely vegetated areas are
considered those in which the planting type and spacing is such that the flow of water is
impeded.
Planters should be built so that water from them will not seep into the foundation, slab,
or pavement areas. Site irngation should be limited to the minimum necessary to sustain
landscaping plants. Should excessive irngation, water line breaks, or unusually high
rainfall occur, saturated zones or "perched" groundwater may develop in fill soils. This
condition may result in excessive moisture migration into and through foundations and
slabs. Damage to landscape may also occur.
9.4 Settlement Monitoring
Consolidation of the alluvium due to the weight of the planned fill was monitored during
fill placement and evaluated using settlement monuments. The settlement monuments
consisted of 24-inch-square steel plates with y4-inch-diameter iron pipe extensions. The
pipe was added as the fill placement progressed upward. The tops of the pipes were
surveyed by O'Day Consultants on a regular basis and provided to us for our review. The
approximate locations of the settlement monuments are presented on the Geotechnical
Maps. Plates 1 through 4.
Preliminary estimates by San Diego Soils Engineering. Inc. (1986) of the alluvial
settlement was on the order of up to 5 inches. Based on the settlement data obtained
during grading, settlement of up to approximately ^-'A inches was observed in Monument
1 located in Lot 42. Settlement of about 1 to 2-72 inches was measured in Monuments
2 through 7. Monument 4 currently shows about 4 inches of settlement. The settlement
data is presented on Figures 2.1 through 2.8, Settlement Monument Data.
Based on the settlement data, it appears the areal settlement is essentially complete. The
amount of settlement measured during grading is within the amounts estimated in the
preliminary geotechnical investigation. Future settlement may occur in addition to the
measured values. The amount of future settlement depends on the amount of irrigation
Geotechnics Incorporated
m m
IP
„ ,, Project No. 0002-008-03
Brookfield Davidson Homes Document No, 6-0461
Broccato at Batiquitos Shores p
November 7. 1996 . '•—
by the homeowners. Structures should be designed for the settlement values given in
Section 9.5.1.
9.5 Foundations
The following recommendations are based on our testing and observation ofthe grading,
the laboratory testing of the soil near finish grade, and are considered generally consistent
with methods typically used in southem Califomia. Other altematives may be available.
The foundation recommendations herein should not be considered to preclude more
restrictive criteria of goveming agencies or by the structural engineer. The design of the
foundation system should be performed by the project structural engineer incorporating
the geotechnical parameters described in the following sections.
In general, the expansion index testing indicated that the soils exhibit very low and low
expansion potential except for Lots 69 and 70 which exhibited a medium expansion
potential. The following parameters assume an expansion index of less than 90, and that
the structure will be founded either entirely on compacted fill or entirely on relatively
undisturbed formational material. We understand that post-tensioned slabs will be used
at each of the lots.
9.5.1 Post-Tensioned Slabs
For design of post-tensioned slabs, a bearing value of 2,000 pounds per square
foot and a differential settlement value of I-V2 inches may be used for design. A
one-third increase in the bearing value may be used for short term wind and
seismic loading. A minimum footing embedment depth of 18 inches below the
lowest adjacent grade should be provided.
9.5.2 Lateral Resistance
Lateral loads against strtictures may be resisted by friction between the bottoms
of footings or slabs and the supporting soil. A coefficient of friction of 0.3 is
recommended. Altematively. a passive pressure of 300 pcf is recommended for
the portion of vertical foundation members embedded into formational soil. If
friction and passive pressure are combined, the passive pressure value should be
reduced by one-third.
Geotechnics Incorporated
Brookfield Davidson Homes Project No. 0002-008-03
Broccato at Batiquitos Shores Document No. 6-0461
November 7, 1996 Page No. 11
9.5.3 Slope Setback
Footings on slopes should be founded at a depth such that the distance between
the lower outside edge of the footing and the face of any slope is at least 5 feet.
9.5.4 Moisture Protection for Slabs
Concrete slabs constructed on soil ultimately cause the moisture content to rise
in the underiying soil. It is our understanding that the planned moisture protection
for slabs on grade is to consist of 2 inches of sand, over a 6-mil visqueen vapor
barrier. It has been our experience that such systems will transmit from
approximately 6 to 12 pounds of moisture per 1000 square feet per day. It is our
opinion that soil conditions do not exist that would preclude the use of the
indicated moisture protection on this project. It should be recognized, however,
that this system relies entirely on the integrity of the visqueen membrane.
Accordingly, care should be taken to protect the visqueen against all punctures
and to provide adequate overiap at all seams. To further reduce the amount of
moisture migration, we recommend placing a 4-inch thick layer of coarse sand
over the visqueen.
9.6 Exterior Slabs
Reinforcement and the use of crack control joints should help control random cracking and
differential movement. Slabs should be at least 4 inches in thickness and should be
reinforced with at least 6-inch by 6-inch, W1.4 by W1.4 welded-wire fabric. Slabs may
bear directly on compacted subgrade. Crack control joints should be provided on at least
5-foot centers each way.
9-7 Earth Retaining Structures
Retaining walls should be backfilled with material exhibiting a low expansion potential, less
than 35 as evaluated by UBC Standard 29-2 (Expansion Index test). Materials exhibiting
a greater expansion potential would increase the lateral pressures beyond design values.
The following design parameters for earth retaining structures are provided assuming
backfill with a low potential for expansion.
Geotechnics Incorporated
Brookfield Davidson Homes
Broccato at Batiquitos Shores
November 7, 1996
Project No, 0002-008-03
Document No, 6-0461
Page No, 12
Equivalent Fluid Pressure with level backfill:
Equivalent Fluid Pressure with 2:1 sloping backfill:
Allowable Soil Bearing:
Passive Pressure:
Coefficient of Friction, soil to concrete:
35 Ibs/ft'
45 Ibs/ft'
2.000 Ibs/ft^
300 Ibs/ft'
0.3
ii
The equivalent fluid pressures are based on the active soil stale, assuming the walls are
free to rotate at least 1 percent of the wall height. The pressures do not include
surcharge loads, hydrostatic pressure, or seepage forces. Walls should be fully drained
to prevent hydrostatic or seepage pressures. When combining passive pressure and
friction for passive resistance, the passive pressure should be reduced by one-third.
It has been our experience that site retaining walls frequently develop high moisture or
free water in the backfill due to heavy irrigation that commonly occurs in subdivisions.
This leads to problems such as efflorescence on the face of the wall and spalling of
stucco finishes. To decrease such problems, it is suggested that walls be moisture-
proofed on the positive side in addition to having a back-drain.
Retaining wall backfill should be compacted to at least 90 percent relative compaction
(ASTM D1557-91). Backfill should not be placed until walls have achieved adequate
structural strength. Heavy compaction equipment which could cause distress to walls
should not be used. Temporary excavations in compacted fill greater than 4 feet in height
should be no steeper than 1:1 (horizontal to vertical). Temporary excavations in
formational materials should be no steeper than %:1.
10.0 UMITATIONS
Our services were performed using the degree of care and skill ordinarily exercised, under similar
circumstances, by reputable soils engineers and geologists practicing in this or similar localities.
No other warranty, expressed or implied, is made as to the conclusions and professional advice
included in this report. The samples taken and used for testing, the observations made and the
in-place field testing performed are believed representative of the project; however, soil and
geologic conditions can vary significantly between tested or observed locations.
Geotechnics Incorporated
Brookfield Davidson Homes
Broccato at Batiquitos Shores
November 7, 1996
Project No. 0002-008-03
Document No. 6-0461
Page No. 13
This report is issued with the understanding that it is the responsibility of the owner, or of his
representative, to ensure that the information and recommendations contained herein are brought
to the attention of the architect and engineer for the project and incorporated into the plans, and
the necessary steps are taken to see that the contractor and subcontractors carry out such
recommendations in the field.
As in most major projects, conditions revealed by excavation may be at variance with preliminary
findings. If this occurs, the changed conditions must be evaluated by Geotechnics Incorporated
and designs adjusted as required or altemate designs recommended. Although our observations
and testing did not reveal deficiencies, we do not guarantee the contractor's work, nor do the
services provided by Geotechnics relieve the contractor of responsibility in the event of
subsequently discovered defects in his work.
The findings of this report are valid as of the present date. However, changes in the conditions
of a property can occur with the passage of time, whether they be due to natural processes or
the works of man on this or adjacent properties. In addition, changes in applicable or appropriate
standards may occur, whether they result from legislation or the broadening of knowledge.
Accordingly, the findings ofthis report may be invalidated wholly or partially by changes outside
our control. Therefore, this report is subject to review and shouid not be relied upon after a
period of three years.
GEOTECHNICS INCORPORATED
Robert A. Torres, P.E. C 43077
Senior Engineer
W. Lee Vanderhurst, C.E.G. 1125
Principal
Anthony F. Belfast, P.E. C 40333
Principal
Geotechnics Incorporated