HomeMy WebLinkAboutCT 99-08; SPYGLASS; UPDATE GEOTECHNICAL INVESTIGATION; 1999-04-01<^T 11-68
UPDATE
GEOTECHNICAL INVESTIGATION
SPYGLASS
CARLSBAD, CALIFORNIA
PREPARED FOR
LANDIS INDUSTRIES, INC.
ANAHEIM, CALIFORNIA
APRIL 1999
GEOCON
INCORPORATED GEOTECHNICAL CONSULTANTS
ProjectNo. 06301-12-01
April 28, 1999
Landis Industries, Inc.
5753 East Santa Ana Canyon Road, Suite G
Anaheim, Caiifornia 92807
Attention:
Subject:
Mr. John L. Wismer
SPYGLASS
CARLSBAD, CALIFORNIA
UPDATE GEOTECHNICAL INVESTIGATION
Gentlemen:
In accordance with your authorization and our proposal dated April 12, 1999, we have reviewed and
updated our original study for the subject project entitled GeorecAn/ca/ Investiganon ^^^^^^^^^^
Lonnaissance [for] Spyglass-Elm Avenue, Carlsbad. Cahfomia, f^'!'^'fJJJ'f^^^^^
No D-4394-J01). hi addition a site recomiaissance was perfomied on Apnl 8, 1999, at which time it
was observed that the site remains essentially unchanged since the submittal of the ongmal report^
TTie accompanying report presents the results of our smdy and conclusions and recommendation
pertaining to deve^ping the property as presently proposed. Provided the recommendations ofthis
report are followed, the site is considered suitable for development as currently plamied.
Should you have any questions regarding this report, or if we may be of further service, please
contact the undersigned at your convenience.
Very truly yours
GEOCON INCORP
David F. i4e:
RCE 2252'
ASiDFLidmc
(6) Addressee
TABLE OF CONTENTS
1. PURPOSE AND SCOPE ^
2. SITE AND PROJECT DESCRIPTIONS ^
3. SOIL AND GEOLOGIC CONDITIONS ^
3.1. Fill (Qaf) 2
3.2. Colluvium/Topsoil (Unmapped) ^
3.3. Alluvium (Qal) ^
3.4. Santiago Fonnation (Ts)
3
4. GROUNDWATER
3
5. STRUCTURE
6. GEOLOGIC HAZARDS ^
6.1. Faulting and Seismicity ^
6.2. Seismic Design Criteria ^
6.3. Liquefaction ^
6.4. Landslides
7. CONCLUSIONS AND RECOMMENDATIONS ^
7.1. General ^
7.2. Soil and Excavation Characteristics ^
7.3. Grading g
7.4. Subdrains 'g
7.5. Slope Stability '^
7.6. Earthwork Grading Factors ^
7.7. Foundation Recommendations '^^
7.8. Retaining Walls and Lateral Loads
7.9. Slope Maintenance
7.10. Drainage j5
7.11. Plan Review
LIMITATIONS AND UNIFORMITY OF CONDITIONS
MAPS AND ILLUSTRATIONS
Figure 1, Vicinity Map
Figure 2, Geologic Map (Map Pocket)
Figure 3, Typical Subdrain Detail
Figure 4, Typical Stability Fill Detail
Figure 5 Cut Slope Stability Analysis
Figure 6, Fill Slope Stability Analysis
Figure 7, Surficial Slope Stability Analysis
TABLE OF CONTENTS (Continued)
APPENDIX A
FIELD INVESTIGATION
Figures A-1-A-10, Logs of Borings
Figures A-ll-A-23, Logs of Trenches
APPENDIXB
LABORATORY TESTING
Table B-I, Summary of Laboratory Maximum Dry Density and Optimum Moisture
Content Test Results
Table B-II, Summary of Direct Shear Test Results
Table B-III, Summary of Laboratory Expansion Index Test Results
APPENDIX C
RECOMMENDED GRADING SPECIFICATIONS
UPDATE GEOTECHNICAL INVESTIGATION
1. PURPOSE AND SCOPE
This report presents the results of a geotechnical investigation for the Spyglass Property located at
the southeast comer ofthe intersection of El Camino Real and Carlsbad Village Drive, in Carlsbad,
Califomia (see Vicinity map. Figure 1). The purpose ofthe investigation was to evaluate the surface
and subsurface soil and geologic conditions encountered and to provide recommendations pertammg
to the geotechnical aspects of future development.
The scope ofthe geotechnical investigation included a review ofthe following:
1 Geotechnical Investigation and Geologic Reconnaissance for Spyglass Elm Avenue.
Carlsbad. Califomia, prepared by Geocon Incorporated, dated July 17, lysy.
2 Geologic Maps ofthe Northwestem Part of San Diego County, California prepared by
Califomia Division of Mines and Geology, 1996 (DMG Open File Report 96-2).
3. Tentative Map. Carlsbad Califomia, prepared by Tait Consulting, undated.
4. Unpublished reports, aerial photographs and maps on fde with Geocon Incorporated.
The scope ofthe field investigation consisted of a geologic reconnaissance and the excavation of 4
large-diameter exploratory borings and excavation of 13 trenches. Logs of the exploratoo'
excavations are presented in Appendix A. Tlie approximate locations ofthe explorato^. excavations
are depicted on the Geologic Map (Figure 2).
Laboratoiy tests were perfomied on selected soil samples to evaluate pertinent physical properties.
Details of the field investigation and laboratory tests are presented in Appendices A and B,
respectively.
tte commendations presented herein are based upon an analysis of the data obtained in the
refereneed report, observations dnring this investigation and our expedence w,U, similar soil and
geologic conditions.
2. SITE AND PROJECT DESCRIPTIONS
The site consists of approximately 10.4 acres of undeveloped land at *=
interseaion of El Camino Re^ and Carlsbad Village Drive in Carlsbad, California -™ M^P-
Figure 1). THe site is triangular in shape and generally slopes downward moderately steep y to *
„1 An alluvial filled drainage which trends east-wes. crosses the site on f -"*™
IL extension of Appian Road is proposed to continue fh,m the soutii side ofthe site to its norihen,
Project No. 06301-12-01
" ApriiaS, 1999
1 -
temiinus at the intersection with Carisbad Village Drive. Additional interior site access will be
provided by a cul-de-sac extending from Appian Road towards the east. An existing slope inclined at
approximately 1:1 (horizontal to vertical) is located along portions of El Camino Real and an existing
slope inclined at approximately 2:1 bounds a portion of Carisbad Village Drive. Several other natural
and graded slopes of varying heights and inclinations bound the eastem side of the site adjacent to the
existing residential development. Previous site grading included the cutting of a relatively flat pad at
the intersection of Carlsbad Village Drive and El Camino Real.
The referenced plans indicate that the site will be graded for 19 single-family residential building pads.
Elevations within the site range from a low of approximately 136 feet Mean Sea Level (MSL) in the
northwest comer ofthe site to a high of approximately 270 feet MSL in die northeast comer ofthe s.te.
A major slope will be graded along El Camino Real at an inclination of 2:1 or flatter and a maximum
height on the order of 50 feet. Similar size slopes will be constmcted along portions of Carlsbad
Village Drive. Maximum cuts and fills on the order of 25 feet and 50 feet, respectively, are proposed.
3. SOiL AND GEOLOGIC CONDITIONS
Three surficial soil types and one geologic fomiation exist at the subject property. The surficial units
include undocumented fill, topsil, and alluvium. The geologic unit encountered is the Eocene-aged
Santiago Fomiation. Each ofthe soil types and geologic fomiations is discussed below m order of
increasing age. Their estimated areal extent is shown on the Geologic Map, Figure 2 (map pocket).
The limits ofthe colluvium is not shown since it covers most of the site as a thin veneer.
3.1. Fill (Qaf)
Several minor areas of previously placed fill soils were encountered during the field investigation.
The fills appear to have been associated with prior site grading including the placement of the
adjacent subdivision and stomi drain trench backfill. The fills soils obsen/ed were typ-Uy very
shallow and consisted of mixtures ofthe onsite materials, which are predominantly s.lty sands and
clays. The fill soils were generally loose and should not be considered suitable to support either
additional fill soils or settlement sensitive improvements in their present condition due to their
compressibility characteristics. Remedial recommendations are provided under the Conclusions and
Recommendations section ofthis report.
3.2. Colluvium/Topsoil (Unmapped)
colluvium/topsoil covers most ofthe natiiral a.as ofthe site, tte ^^^^'^^^^
thin layer of less than 2 feet in thickness: ttese materials observed ranged from a 1™=.'>"""4 'sh
bin silty fine to coarse sand to a stiff, moist, dark brown sandy clay, tte colluvium/topsoil is no.
ProjectNo. 06301-12-01
considered suitable to receive either additional fill soils or to support settlement sensitive
improvements in their present condition due to their low moisture content and compressibility
characteristics.
3.3. Alluvium (Qal)
Alluvial soils were encountered in the drainage which crosses the southem half of the site. The
alluvial soils in the drainage average approximately 10 feet in thickness with a maximum of 15 feet
encountered in Trench T-6. Localized deeper areas may be present. These soils typically consisted
of dense, slightly moist, brown to grey, silty and clayey sands and were often mottled and porous.
The alluvial soils will require removal and recompaction in areas where settlement sensitive
improvements are proposed.
3.4. Santiago Formation (Ts)
Eocene-aged Santiago Fomiational soils were found to underlay the site. Silty or clayey sandstones
are predominant in the fomiation with interbedded clayey siltstones and silty claystones. The
materials are typically dense to very dense, slightly moist to moist, and should be suitable bearing
soils in either a nattiral or a properly recompacted condition. Portions of this fomiation may be
expansive and are not recommended for use at finish pad grade with standard foundations or within
the outer 15 feet of fill slopes.
4. GROUNDWATER
No groundwater was encountered during the field investigation, however, seepage was observed in
Boring No. B-4 at approximately 34 feet below existing ground surface. During the recent site
reconnaissance, seepage was observed at the toe ofthe existing slope along the southwest comer of
the site Due to the interbedded claystones and siltstones within the very penneable sandstones it is
likely that seasonal seeps, perched water tables and ponding water problems may result due to
increased precipitation and imgation. It is anticipated that seepage may be encountered during
grading depending on when grading is perfomied. Remedial grading recommendations are provided
later in this report. Due to the granular namre of much ofthe material on die site it is antic ipatec^ that
seasonal water will migrate throughout the site drainages and therefore canyon subdrains should be
installed during grading as outlined in the Conclusions and Recommendations.
5. STRUCTURE
Regionally the Santiago Fomiation has a west to southwest dip of several degrees which may affect
the stability of the proposed slopes. Locally observed bedding in the borings was predominantly
ProjectNo. 06301-12-01
northwest dipping and will require that all cut slopes be observed and mapped during grading to
determine if stability or buttress fills are required.
6. GEOLOGIC HAZARDS
6.1. Faulting and Seismicity
A review of geologic literattire, experience with the soil and geologic conditions in the general area,
and observations during the field investigation indicate that no active faults are located at die site.
The nearest known active faults are the Rose Canyon and Newport-Inglewood Fault Zones located
approximately 6 miles northwest and west ofthe site. Maximum Credible and Maximum Probable
seismic events of Magnittide 6.9 and Magnittide 5.7, respectively, are posttilated for the these fault
zones.
The estimated Maximum Credible and Maximum Probable peak site accelerations are 0.25 g and
0 13 g respectively. The maximum effective ground motion, however, is estimated to be
approximately 0.18 g for the same seismic event. The effective ground motion is associated with the
significant part ofthe ground motion containing repetitive motions that possess strong energy content
and that produce stmcttiral defonnation. It has been estimated by Ploessel and Slosson (1974) that
effective ground acceleration is equal to approximately 65 to 70 percent ofthe peak ground motion
for earthquakes within 20 miles of a site. Seismic parameters for other regional faults capable of
generating ground acceleration at the site are summarized below.
TABLE 6.1. ^ ^
Fault Name
Compton Thrust
Elsinore-Julian
Distance
From Site
(miles)
56
23
Maximum Credible Event Maximum Probable Event
Fault Name
Compton Thrust
Elsinore-Julian
Distance
From Site
(miles)
56
23
Maximum
Credible
(Mag.)
6.8
7.1
£ o
Peak Site
Acceleration
(g)
0.09
0.11
n in
Maximum
Probable
(Mag.)
5.8
6.4
6.3
Peak Site
Acceleration
(g)
0.05
0.08
0.08
EIsinore-Temecula
Coronado Bank
Newport-Inglewood (offshore)
Rose Canyon
23
23
6
6
6.8
7.4
6.9
6.9
\j. i\j
0.14
0.25
0.25
6.3
5.8
5.7
0.08
0.14
0.13
,t is our opinion that the site could be subjected to moderate to severe ground ~n J^^^^
a major earthquake along any ofthe above mentioned faults, however *e -"^^'^^^
no. considered to be significantly different than tha. of the sutroundmg developments of similar
geologic settings in the Carlsbad area.
ProjectNo. 06301-12-01
6.2. Seismic Design Criteria
The following table summarizes site-specific seismic design criteria obtained from the 1997 Unifonn
Building Code (UBC). The values listed in Table 6.2 are for the Rose Canyon Fault (located
approximately 6 miles west ofthe site) which is identified as a Type B fault and is more dominant
than the nearest Type A fault (Elsinore) due to its close proximity to the site.
TABLE 6.2
SEISMIC DESIGN PARAMETERS
Parameter Value UBC Reference
Seismic Zone Factor, Z 0.40 Table 16-1
Soil Profile Type Sc Table 16-J
Seismic Coefficient, C, 0.40 Table 16-Q
Seismic Coefficient, Cy 0.56 Table 16-R
Near-Source Factor, N, 1.0 Table 16-S
Near-Source Factor, Ny 1.0 Table 16-T
Seismic Source B Table 16-U
6.3. Liquefaction
Liquefaction occurs in loose cohesionless soils located below the water table that are subjected to
large accelerafions during strong earthquakes. Due to the very dense namre ofthe fomiational units,
the removal and recompaction ofthe surficial soils, and the lack of a pennanent .groundwater table,
the potential for liquefaction ofthe site subsoils is considered to be very low.
6.4. Landslides
No landslides or indicafions of landslides were noted during our field invesfigafions on the site or
immediately adjacent to the site. No indications of landslides were noted on the aenal photographs
reviewed.
ProjectNo. 06301-12-01
7. CONCLUSIONS AND RECOMMENDATIONS
7.1. General
7.1.1. No soil or geologic conditions were encountered during this geotechnical invesfigation
performed by Geocon Incorporated that would preclude the development of the property
provided that the recommendafions of this report are followed.
7.1.2. The surficial soils such as undocumented fill soils, topsoil, and alluvium within areas of
planned development are not considered suitable for support of stmcmral fill or stmctural
loads in their present condition and will require remedial grading in the form of removal
and recompacfion. Also the debris and trash will need to be removed and disposed of
off-site.
7.2. Soil and Excavation Characteristics
7.2.1. The prevailing soil conditions encountered during the field explorafion consisted of low-
expansive sands derived from portions of the surficial soils and the sandy portion of the
Sanfiago Fomiafion. The fine-grained surficial soils and siltstones and claystones ofthe
Santiago Fonnation possess medium to high expansion potential.
7.2.2. It is anficipated that the surficial deposits can be excavated with a light effort using
conventional heavy duty grading equipment. A moderate to heavy effort is anficipated for
excavations within the formational sedimentary units.
7.2.3. Deeper alluvial soils may be very moist to samrated during the winter or early spring
depending on the preceding precipitation and may require mixing with drier materials or
drying prior to their use as compacted fill.
7.3. Grading
73 1 All grading should be perfonned in accordance with the Recommended Grading
Specifications in Appendix C and the City of Carlsbad Grading Ordinance. Where the
recommendations ofthis secfion conflict with those in Appendix C, the recommendations
ofthis section take precedence. All earthwork should be observed and all fills tested for
proper compaction by Geocon Incorporated.
7 3 2 Prior to commencing grading, a preconsttniction conference should be held at the site with
the owner or developer, grading contractor, civil engineer and geotechnical engineer in
attendance. Special soil handling and/or the grading plans can be discussed at that time.
Project No. 06301-12-01
n " April 28, 1999
7.3.3. Site preparation should begin with the removal of all deleterious material and vegetafion.
The depth of removal should be such that material exposed in cut areas or soils to be used
as fill are relatively free of organic matter. Material generated during stripping and/or site
demolition should be exported from the site.
7.3.4. Except as noted below, all compressible surficial soil deposits (undocumented fill, topsoil,
and alluvium) within areas of planned grading should be removed to firm namral ground
and properly compacted prior to placing additional fill and/or stmcttiral loads. Removals
along the edge of grading should include excavafion of unsuitable soils that would
adversely affect the perfonnance of the planned fill, i.e., extend removals within a zone
defined by a line project down and out at a slope of 1:1 fi-om the limit of grading to
intersect with finn namral ground except where limited by project boundary constraints.
7.3.5. The acmal extent of unsuitable soil removals will be determined in the field during grading
by the soil engineer and/or engineering geologist.
7.3.6. Aflier removal of unsuitable materials as recommended above, the site should then be
brought to final subgrade elevations with stmcmral fill placed and compacted in layers.
Prior to placing fill, the exposed namral ground surface should be scarified to a depth of at
least 12 inches, moismre conditioned and compacted. In general, soils native to the site are
suitable for use as fill if free from vegetation, debris and other deleterious material. Layers
of fill should be no thicker than will allow for adequate bonding and compacfion. All fill,
including scarified ground surfaces, should be compacted to at least 90 percent of
laboratory maximum dry density in accordance with ASTM Test Procedure D-1557-91, at
or slightly above optimum moismre content. Fill materials with in-place density test results
indicating moismre contents less than optimum will require additional moismre
conditioning before placing additional fill.
7.3.7. To reduce the potential for differential settlement, it is recommended that the cut portion of
cut/fill transition building pads be undercut at least 3 feet and replaced with properly
compacted low expansive fill soils. The undercut should extend fi-om the back ofthe pad
to the street and be graded at a gradient of at least 1 percent towards the stt-eet.
7.3.8. Grading operations should be scheduled so as to pennit the placement of oversized rock
and expansive soils in the deeper fills and to cap the building pads with at least 3 feet of
granular materials having a low expansive potenfial (Expansion Index less than 50 per
UBC Table 18-I-B). Oversized rock, if encountered, should be placed at least 10 feet
below finish grade or 3 feet below the deepest utility, whichever is greater.
— • —r- ^" April 28, 1999
ProjectNo. 06301-12-01 ^ '
7.4. Subdrains
7.4.1. A subdrain should be installed within the east-west-ttending drainage to be filled. The
subdrain should be installed with the upstteam end at a minimum of 10 feet below the
proposed finished grades. A cross-section of the recommended subdrain configuration is
presented on Figure 3. Due to the depth of removals near the west property line, the
subdrain may require outletting to the storm drain planned for the northwest comer ofthe
site. After installation ofthe subdrain, the project civil engineer should survey its location
and elevation and prepare "as-built" plans of subdrain locations.
7.5. Slope Stability
7.5.1. The results ofthe investigation indicate a seepage condition within the southwest comer of
the property. It is recommended that the planned cut slope facing El Camino real be
consttucted as a drained stability fill. This will allow installafion of a drainage system
(drainage panels and heel drain) to intercept seepage water within the fill slope and
mitigate the adverse affect of water seeping through the slope. A typical stability fill detail
is shown on Figure 4.
7 5 2 The results of analyses indicate that cut and fill slopes have a factor of safety in excess of
1.5 for the maximum anticipated heights (see Figures 5 and 6). Surficial slope stability
analysis of fill slopes also indicates a factor of safety in excess of 1.5 (see Figure 7).
7 5 3 It is recommended that all cut slopes be observed during grading by an engineering
geologist to verify that the soil and geologic condifions do not differ significantly from
those anficipated and to detemiine if adverse bedding, fracmres or joints exist. Remedial
grading procedures can be recommended should adverse geologic conditions be observed.
7 5 4 The outer 15 feet of fill slopes, measured horizontal to the slope face, should be composed
of properiy compacted "granular soil" fill to reduce the potential for surface sloughing.
7 5 5 All fill slopes should be overbuilt at least 3 feet horizontally, and cut to the design finish
grade As an altemative, fill slopes may be compacted by back-rolling at vertical intervals
not to exceed 4 feet and then track-walking with a D-8 dozer, or equivalent, upon
completion such that the fill soils are unifomily compacted to at least 90 percent relative
compaction to the face of the finished slope.
7 5 6 In our opinion, the use of tenace drains on cut or fill slopes exceeding 30 feet in height is not
necessaiy to maintain gross stability of the slopes. It is our opinion, that on the cut slopes
proposed the addition of benches will increase slope heights and surface area without
ProjectNo. 06301-12-01
7.5.7.
providing any significant effect on erosion conttol. If used, it is recommended that the
tenace drains be consttucted at a drainage gradient of at least 5 percent. In addition, the need
to properly maintain the drains is important. Drains which are not periodically cleaned of
vegetation and debris could result in significant slope disttess and erosion.
All slopes should be planted, drained and properly maintained to reduce erosion.
7.6. Earthwork Grading Factors
7.6.1. Estimates of embankment shrink-swell factors are based on comparing laboratory
compaction tests with the density of the material in its namral state and experience with
similar soil types. It should be emphasized that variations in nattiral soil density, as well as
in compacted fill, render shrinkage value estimates very approximate. As an example, die
conttactor can compact fills to any relative compaction of 90 percent or higher of the
laboratory maximum dry density. Thus, the conttactor has at least a 10 percent range of
conttol over the fill volume. Based on our experience and laboratory testing in similar
geologic materials, the following earthwork factors may be used as a basis for estimating
how much the on-site soils may shrink or swell when removed from their nattiral state and
placed in compacted fills. It is recommended that the grading be monitored during
earthwork operations and that a balance area be designated to provide adjustments to the
cut/fill as necessary.
TABLE 7.6.
Soils Unit Shrink-Swell Factors
Fill Soils, Topsoil, and Alluvium 5% to 10% Shrinkage
Santiago Formation 2% to 10% Bulk
7.7. Foundation Recommendations
7 7 1 The following foundation recommendafions are for one-and/or two-story sttucmres and are
based upon the assumption that the soil conditions within 3 feet of finish pad subgrade
consist of granular "low" expansive soil (Expansion Index less than 50). The
recommendations are separated into categories dependent upon the depth and geometn^ of
fill underiying a particular building pad and/or lot and where alluvium left-in-place may
influence the perfomiance of improvements. Final foundation design recommendations for
each building will be presented in the final compaction report after the gradmg for the
individual building pads has been completed.
ProjectNo. 06301-12-01 •9-April 28, 1999
TABLE 7.7.1.
FOUNDATION RECOMMENDATIONS BY CATEGORY
Foundation
Category
Minimum
Footing
Depth
(inches)
Continuous Footing
Reinforcement
Interior Slab
Reinforcement
I 12 One No. 4 bar top and bottom 6 X 6 - 10/10 welded wire mesh
at slab mid-point
II 18 Two No. 4 bars top and bottom No. 3 bars at 24 inches on
center, both directions
III 24 Two No. 5 bars top and bottom No. 3 bars at 18 inches on
center, both directions
CATEGORY CRITERL\
Category I:
Category II:
Category III:
Maximum fill thickness is less than 20 feet and Expansion hidex is less than or
equal to 50.
Maximum fill thickness is less than 50 feet and Expansion Index is less than or
equal to 90, or variation in fill thickness is between 10 feet and 20 feet.
Fill thickness exceeds 50 feet, or variadon in fill thickness exceeds 20 feet, or
Expansion Index exceeds 90, but is less than 130, or underiam by alluvium left-m-
place (zone of influence).
7.7.2.
7.7.3.
Notes:
I. All footings should have a minimum width of 12 inches.
2 Footing depth is measured from lowest adjacent subgrade (including topsoil, if planned). Tbese
depths apply to both exterior and interior footmgs.
3 All interior living area concrete slabs should be at least 4 inches thick for Categories I and II
ild?incL thick for Category III. This applies to both building and garage slabs-on-grade.
4. All interior concrete slabs should be underlain by at least 4 inches (3 inches for Category III) of
clean sand or cmshed rock.
^ All slabs exoected to receive moisttire sensitive floor coverings or used to store moisture
feLiS^ mSs slid be underlain by a vapor barrier covered with at least 2 mches ofthe
clean sand recommended in No. 4 above.
Foundations for either Category I, II, or III may be designed for an allowable soil l^aring
pressure of 2,000 pounds per square foot (psf) (dead plus live load), ttis beanng pressure
may be increased by one-third for transient loads such as wind or seismic forces.
tte use of isolated footings which, ar. located beyond the perimeter ofthe building and
: Stiuctural elements connected to the building is no. recommended for C.ego^ IH^
Were tiiis condi.ion canno. be avoided, Ae isola.ed footings should be comiected to the
building foundation system with grade beams.
ProjectNo. 06301-12-01
7.7.4. For Foundafion Category III, the strucmral slab design should consider using interior
stiffening beams and connecting isolated footings and/or increasing the slab thickness. In
addition, consideration should be given to connecting patio slabs, which exceed 5 feet in
widtii, to the building foundation to reduce the potential for futtire separation to occur.
7.7.5. No special subgrade preparation is deemed necessary prior to placing concrete, however,
the exposed foundation and slab subgrade soils should be sprinkled, as necessary, to
maintain a moist soil condition as would be expected in any such concrete placement.
7.7.6. Where buildings or other improvements are planned near the top of a slope steeper than 3:1
(horizontahvertical), special foundations and/or design considerations are recommended
due to the tendency for lateral soil movement to occur.
For fill slopes less than 20 feet high, building footings should be deepened such
that the bottom outside edge ofthe footing is at least 7 feet horizontally from the
face of the slope.
Where the height of the fill slope exceeds 20 feet, the minimum horizontal distance
should be increased to H/3 (where H equals the vertical distance from the top of
the slope to the toe) but need not exceed 40 feet. For composite (fill over cut)
slopes H equals the vertical distance from the top of the slope to die bottom ofthe
fill portion ofthe slope. An acceptable altemative to deepening the footings would
be the use of a post-tensioned slab and foundation system or mcreased footing and
slab reinforcement. Specific design parameters or recommendations ^r either ot
these altemafives can be provided once the building locatton and fill slope
geometry have been determined.
For cut slopes in dense fonnational materials, or fill slopes inclined at 3:1 (hori-
zontal-vertical) or flatter, the bottom outside edge ofbuilding footings shoud be at
least 7 feet horizontally from the face ofthe slope, regardless of slope height.
Swimming pools located widiin 7 feet of the top of cut or fill slopes are not
recommended. Where such a condition cannot be avoided, it is recommended that
the portion ofthe swimming pool wall within 7 feet ofthe slope face be designed
as umTng that the adjacent soil provides no lateral support. This —"da^^^^^
aoDlies to fill slopes up to 30 feet in height, and cut slopes regardless of height. For
swtm ng pools'locat'ed near the top of fill slopes greater than 30 feet in height
additional recommendations may be required and Geocon Incorporated should be
contacted for a review of specific site conditions.
Although other improvements which are relatively rigid or brittle such as concrete
flaSTrk or masono' walls may experience some distress if located near the top of a
fioTe it is gl ralb^ not economical to mitigate this potential. It may be possibl
howevi to incorporate design measures which would pemiit some latera soil
iTvement withouT causing extensive distress. Geocon Incorporated should be
consulted for specific recommendations.
ProjectNo. 06301-12-01
7.7.7. As an altemative to the foundation recommendations for each category, consideration
should be given to the use of post-tensioned concrete slab and foundation systems for the
support of the proposed stmcmres. The post-tensioned systems should be designed by a
stmcmral engineer experienced in post-tensioned slab design and design criteria of tiie
Post-Tensioning Instimte (UBC Section 1816). Altiiough this procedure was developed for
expansive soils, it is understood that it can also be used to reduce die potential for
foundation disttess due to differential fill settlement. The post-tensioned design should
incorporate the geotechnical parameters presented on die following table entitled Post-
Tensioned Foundation System Design Parameters for the particular Foundation Category
designated.
TABLE 7.7.2.
POST-TENSIONED FOUNDATION SYSTEM DESIGN PARAMETERS
Post-Tensioning Institute (PTI)
Design Parameters
Foundation Category Post-Tensioning Institute (PTI)
Design Parameters I II Ill
1. Thomdiwaite Index -20 -20 -20
2. Clay Type - Montmorillonite Yes Yes Yes
3. Clay Portion (Maximum) 30% 50% 70%
4 Depth to Constant Soil Suction 7.0 ft. 7.0 ft. 7.0 ft.
5. Soil Suction 3.6 ft. 3.6 ft. 3.6 ft.
6. Moisture Velocity 0.7 in./mo. 0.7 in./mo. 0.7 in./mo.
7. Edge Lift Moisture Variation Distance 2.6 ft. 2.6 ft. 2.6 ft.
8. Edge Lift 0.41 in. 078 in. • 1.15 in.
9. Center Lift Moisttire Variation Distance 5.3 ft. 5.3 ft. • 5.3 ft.
10. Center Lift 2.12 in. 3.21 in. 4.74 in.
7.7.8. UBC Section 1816 uses interior stiffener beams in its stmcmral design procedures. Ifthe
stmcmral engineer proposes a post-tensioned foundation design method other than UBC
Section 1816, it is recommended that interior stiffener beams be used for Foundation
Categories II and III. The depth ofthe perimeter foundation should be at least 12 inches
for Foundation Category 1. Where the Expansion Index for a particular building pad
exceeds 50 but is less than 91, the perimeter footing depth should be at least 18 inches; and
where it exceeds 90 but is less than 130, the perimeter footing depth should be at least 24
inches. Geocon Incorporated should be consulted to provide additional design parameters
as required by the stmcmral engineer.
7 7 9 The recommendations of this report are intended to reduce the potential for cracking of
slabs due to expansive soils (if present), differential settlement of deep fills or fills of
ProjectNo. 06301-12-01 - 12-April 28, 1999
varying thicknesses. However, even with the incorporation of the recommendations
presented herein, foundations, smcco walls, and slabs-on-grade placed on such conditions
may still exhibit some cracking due to soil movement and/or shrinkage. The occunence of
concrete shrinkage cracks is independent of tiie supporting soil characteristics. Their
occunence may be reduced and/or conttolled by limiting the slump ofthe concrete, proper
concrete placement and curing, and by die placement of crack confrol joints at periodic
intervals, in particular, where re-entty slab comers occur.
7.8. Retaining Walls and Lateral Loads
7.8.1. Retaining walls not resfrained at the top and having a level backfill surface should be
designed for an active soil pressure equivalent to the pressure exerted by a fluid density
of 30 pounds per cubic foot (pcf). Where the backfill will be inclined at no steeper than 2.0
to 1.0, an active soil pressure of 40 pcf is recommended. These soil pressures assume that
the backfill materials within an area bounded by tiie wall and a 1:1 plane extending upward
from the base of the wall possess an Expansion Index of less than 50. For tiiose lots with
finish grade soils having an Expansion Index greater than 50 and/or where backfill
materials do not confonn to the above criteria, Geocon Incorporated should be consulted
for additional recommendations.
7.8.2. Unrestrained walls are those that are allowed to rotate more than O.OOIH at the top of the
wall. Where walls are resfrained fi-om movement at the top, an additional unifonn pressure
of 7H psf (where H equals the height of the retaining wall portion of the wall in feet)
should be added to the above active soil pressure.
7.8.3. All retaining walls should be provided with a drainage system adequate to prevent the
buildup of hydrostatic forces and should be waterproofed as required by the project
architect. The use of drainage openings through the base ofthe wall (weep holes, etc.) is
not recommended where tiie seepage could be a nuisance or otherwise adversely impact the
property adjacent to the base ofthe wall. The above recommendations assume a properly
compacted granular (Expansion Index less than 50) backfill material with no hydrostatic
forces or imposed surcharge load. If conditions different than those described are
anticipated, or if specific drainage details are desired, Geocon Incorporated should be
contacted for additional recommendations.
7.8.4. In general, wall foundations having a minimum depth and widtii of one foot may be
designed for an allowable soil bearing pressure of 2,000 psf, provided the soil within 3 feet
below the base of the wall has an Expansion Index of less than 90. The proximity of the
foundation to the top of a slope steeper than 3:1 could impact the allowable so.l beanng
ProjectNo. 06301-12-01
•yjjT- — -~~ April 28, 1999
pressure. Therefore, Geocon Incorporated should be consulted where such a condition is
anticipated.
7.8.5. For resistance to lateral loads, an allowable passive earth pressure equivalent to a fluid
density of 300 pcf is recommended for footings or shear keys poured neat against properly
compacted granular fill soils or undismrbed namral soils. The allowable passive pressure
assumes a horizontal surface extending at least 5 feet or three times tiie surface generating
the passive pressure, whichever is greater. The upper 12 inches of material not protected
by floor slabs or pavement should not be included in the design for lateral resistance. An
allowable friction coefficient of 0.4 may be used for resistance to sliding between soil and
concrete. This friction coefficient may be combined witii the allowable passive earth
pressure when determining resistance to lateral loads.
7.8.6. The recommendations presented above are generally applicable to the design of rigid
concrete or masoniy retaining walls having a maximum height of 8 feet. In the event that
walls higher than 8 feet or other types of walls are planned, such as crib-type walls, Geocon
Incorporated should be consulted for additional recommendations.
7.9. Slope Maintenance
7.9.1. Slopes that are steeper than 3:1 (horizontahvertical) may, under conditions which are both
difficult to prevent and predict, be susceptible to near surface (surficial) slope instability.
The instability is typically limited to the outer three feet of a portion of the slope and
usually does not directly impact the improvements on the pad areas above or below the
slope. The occunence of surficial instability is more prevalent on fill slopes and is
generally preceded by a period of heavy rainfall, excessive inigation, or the migration of
subsurface seepage. The dismrbance and/or loosening of the surficial soils, as might result
fi-om root growtii, soil expansion, or excavation for imgation lines and slope planting, may
also be a significant confributing factor to surficial instability. It is, therefore, recom-
mended that, to the maximum extent practical: (a) dismrbed/loosened surficial soils be
eitiier removed or properly recompacted, (b) inigation systems be periodically inspected
and maintained to eliminate leaks and excessive imgation, and (c) surface drains on and
adjacent to slopes be periodically maintained to preclude ponding or erosion. It should be
noted that although the incorporation of the above recommendations should reduce tiie
potential for surficial slope instability, it will not eliminate the possibility, and, therefore, it
may be necessary to rebuild or repair a portion ofthe projecfs slopes in the fiittire.
ProjectNo. 06301-12-01
7.10. Drainage
7.10.1. Establishing proper drainage is imperative to reduce the potential for differential soil
movement, erosion and subsurface seepage. Positive measures should be taken to properiy
finish grade the building pads after sfrucmres and other improvements are in place, so that
drainage water from tiie building pads and adjacent properties is directed to sfreets away
from foundations and tops of slopes. Experience has shown that even with these
provisions, a shallow groundwater or subsurface condition can and may develop in areas
where no such condition existed prior to site development. This is particularly tme where a
substantial increase in surface water infilfration results fi-om an increase in landscape
irrigation.
7.11. Plan Review
7 111 The geotechnical engineer and engineering geologist should review the grading plans prior
to finalization to verify their compliance with the recommendations of this report and
detennine the necessity for additional comments, recommendations and/or analysis. In
addition, the geotechnical engineer should review the sfrucmral foundation plans to venfy
general confonnance with the recoramendations ofthis report.
ProjectNo. 06301-12-01
•yfj^ Aprir28.1999
LIMITATIONS AND UNIFORMITY OF CONDITIONS
1. The recommendations ofthis report pertain only to the site investigated and are based upon
the assumption that the soil conditions do not deviate from those disclosed in tiie
investigation. If any variations or undesirable conditions are encountered during
constmction, or ifthe proposed constmction will differ from that anticipated herein, Geocon
Incorporated should be notified so that supplemental recommendations can be given. The
evaluation or identification ofthe potential presence of hazardous or conosive materials was
not part ofthe scope of services provided by Geocon Incorporated.
2. This report is issued with the understanding that it is the responsibility of the owner, or of his
representative, to ensure that the infonnation and recommendations contained herein are
brought to the attention ofthe architect and engineer for tiie project and incorporated into the
plans, and the necessary steps are taken to see that the confractor and subconfractors cany out
such recommendations in the field.
3. 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 nattiral
processes or the works of man on this or adjacent properties. In addition, changes in
applicable or appropriate standards may occur, whether tiiey result from legislation or the
broadening of knowledge. Accordingly, the findings ofthis report may be invalidated wholly
or partially by changes outside our confrol. Therefore, this report is subject to review and
should not be relied upon after a period of three years.
ProjectNo. 0630.1-12-01 ,
SOURCE: ^9 T™^™,,,
RESALE. WITHOUT PERMISSION
GEOCON
INCORPORAT B D
?9TolSSSv^^ CALIFORNIA 92,2,. 297.
PHONE 6,9 558-6900 • FAX 619 558-6159
AS/TA
IVICMAP
DSK/EOOOD
4
M
NO SCALT
VICINITY MAP
SPYGLASS
CARLSBAD, CALIFORNIA
HATE 04-28-1999 | PROJECT NO. 0^301 - 12-01 | FIG- 1
APPROVED FILTER FABRIC
6" DIA. PERFORATED
SUBDRAIN PIPE
1" MAX. OPEN-GRADED
AGGREGATE 9 CUBIC FT./FT.
MINIMUM
NOTES:
^ ---^ScTE^0ulf4r^^^^
SNECTED"TO STORM SYSTEM OR APPROVED OUTLET
2 WHERE DRAIN EXCEEDS 500 FEET. PIPE DIAMETER SHOULD BE INCREASED
TO 8 INCHES
3 FILTER FABRIC TO BE MIRAFI UON OR EQUIVALENT
NO SCALE
TYPICAL SUBDRAIN DETAIL
GEOCON
IN C O R P O R ATED
?9TJSSv^'& CALIFORNIA 92,2,-297.
PHONE 6,9 558-6900 - FAX 6,9 558-6,59
AS/TA DSK/EOOOO
SPYGLASS
CARLSBAD, CALIFORNIA
DATE 04-28-1 &99. | PROJECT NO. 06301 - 12 - 01 | FIG. 3
so / IXVIII / RSS
FINISHED LOT GFiADE FINISHED SLOPE
NOTE 2
GRADE
WA 15' , t FORMATIONAL
MIN. ' SOIL
NO SCALE
NOTES:
1 EXCAVATE BACKCUT AT 1:1 INCLINATION
2 BASE OF STABIUTY FILL TO BE 3 FEET INTO DENSE. FORMATIONAL SOILS SLOPING
A MINIMUM 5% INTO SLOPE.
3 BUTTRESS FILL TO BE COMPOSED OF PROPERLY COMPACTED GRANULAR SOIL WITH MINIMUM
SHEAR STRENGTH OF ll) = 25°, C = 250 psf
CENTER TO CENTER. ADDITIONAL DRAINS WILL BE REQUIRED WHERE AREAS OF GREAItK atcrMuc
ARE ENCOUNTERED.
5 FILTER MATERIAL TO BE l-INCH. OPEN-GRADED CRUSHED ROCK ENCLOSED IN APPROVED FILTER FABRIC
6 COLLECTOR PIPE TO BE 4-INCH MINIMUM DIAMETER, PERFOf^TED THICK-WALL^^^ SDR 21 OR
^ cnMiVA^ FNT AND SLOPED TO DRAIN AT 1 PERCENT MINIMUM TO APPROVED OUTLET
CSSNEY D^^S ^? BE REQSIRES IF AREAS OF ACTIVE SEEPAGE ARE ENCOUNTERED
7. IF HORIZONTAL EXTENT OF GRADING CONSTF^INEDJ^g THE PRESENCE OF PROPERTY LINE). THE SLOPE
SHOULD BE OVERBUILT AT LEAST 4 FEET, AND TRIMMED BACK
TYPICAL STABILITY FILL DETAIL
GEOCON
INCORPORAT E D
GEOTECHNICAL CONSULTANTS
6960 FLANDERS DRIVE - SAN DIEGO, CAUFORNIA 92121-2974
PHONE 619 558-6900 • FAX 619 558-6159
AS/TA DSK/GTYP1
SPYGLASS
CARLSBAD, CAUFORNIA
DATE: 04-28-1999 I PROJECT NO.06301 -12-OIIF1GJ_
STABFIL6 /DFUlXflXVIURSS
PROJECT NO. 06301-12-01
ASSUMED CONDITIONS:
Slope Height
Slope Inclination
Total Unit Weight of Soil
Angle of Intemal Friction
Apparent Cohesion
No Seepage Forces
H = 40 feet
2:1 (Horizontahvertical)
y, =130 pounds per cubic foot
^ = 27 degrees
C = 440 pounds per square foot
ANALYSIS:
Ac(t( = yHtand) Ac(t( =
C
FS = NcfC
YH
Ac(j) = 6
Ncf = 23
FS = 1.9
Equation (3-3), Reference 1
Equation (3-2), Reference 1
Calculated Using Eq. (3-3)
Determined Using Figure 10, Reference 2
Factor of Safety Calculated Using Eq. (3-2)
REFERENCES:
(1) Janbu, N., Stability Analysis of Slopes with Dimensionless Parameters, Harvard Soil Mechanics,
Series No. 46, 1954.
(2) Janbu N., Discussion of J. M. Bell, Dimensionless Parameters for Homogeneous Eardi Slopes, Joumal of Soil Mechanics and Foundation Design, No. SM6, November 1967.
CUT SLOPE STABILITY ANALYSIS
SPYGLASS
CARLSBAD, CALIFORNIA
FIGURE 5
PROJECT NO. 06301-12-01
ASSUMED CONDITIONS:
Slope Height
Slope Inclination
Total UnitWelght of Soil
Angle of Intemal Friction
Apparent Cohesion
No Seepage Forces
ANALYSIS:
H = 55 feet
2:1 (Horizontal:Vertical)
Y, =125 pounds per cubic foot
^ = 30 degrees
C = 250 pounds per square foot
Ac(|> = yHtan* Ac(|> =
C
FS = NcfC
yH
Ac(j) = 15.9
Ncf = 45
FS = 1.6
Equation (3-2), Reference 1
Calculated Using Eq. (3-3)
Determined Using Figure 10, Reference 2
Factor of Safety Calculated Using Eq. (3-2)
REFERENCES:
(1) Janbu, N., Stability Analysis of Slopes widi Dimensionless Parameters, Harvard Soil Mechanics,
Series'No.46, 1954.
(2) Janbu N., Discussion of J. M. Bell, Dimensionless Parameters for Homogeneous Earth Slopes,
Joumal of Soil Mechanics and Foundation Design, No. SM6, November 1967.
FILL SLOPE STABILITY ANALYSIS
SPYGLASS
CARLSBAD, CALIFORNIA
PROJECTNO. 06301-12-01
ASSUMED CONDITIONS:
Slope Height
Depth of Samration
Slope Inclmation
Slope Angle
Unit Weight of Water
Total Unit Weight of Soil
Angle of Intemal Friction
Apparent Cohesion
H = Infinite
Z = 3 feet
2:1 (Horizontahvertical)
degrees i = 26.5
Yw = 62.4
Yt = 125
"t-= 30
C = 250
poimds per cubic foot
pounds per cubic foot
degrees
pounds per square foot
Slope sattirated to vertical depth Z below slope face.
Seepage forces parallel to slope face
ANALYSIS:
¥S = C + {r,-r JZcos^ i tan (j)
X^Zsinicosz
= 2.2
REFERENCES:
(1) Haefeli, R. The Stability of Slopes Acted Upon by Parallel Seepage. Proc. Second Intemational
Conference, SMFE, Rotterdam, 1948, 1, 57-62.
(2) Skempton, A. W, and F. A. Delory, Stability of NatM^^^ in London Clay, Proc. Fourth
International Conference, SMFE, London, 1957,2, 378-81.
SURFICIAL SLOPE STABILITY ANALYSIS
SPYGLASS
CARLSBAD, CALIFORNLE.
APPENDIX
APPENDIX A
FIELD INVESTIGATION
The field investigation was perfonned during June 23, 26 and 27, 1989 and consisted of and the
excavation of 4 exploratory borings and 13 exploratory frenches at tiie approximate locations shown
on the Site Plan, Figure 1. The borings were advanced to depths ranging fi-om 47 to 70 feet below
existing grade with a 30-inch bucket auger. Relatively undismrbed samples were obtained fi-om the
borings by driving a 3-inch split-mbe sampler 12 inches into the undismrbed soil mass witii blows
from drill rig Kelly bar falling 12 inches. The sampler was equipped with 1-inch by 2V,-inch brass
sampler rings to facilitate removal and testing.
i
The frenches were excavated utilizing a John Deere 555 Track Backhoe witii 24-inch bucket. The
frenches were advanced to depths ranging from 5 to 17 feet below existing grade. The trenches were
visually logged and classified. Bulk samples and chunk samples, representative of the soils
encountered, were obtained and remmed to the laboratory for testing.
During the investigation, the soils encountered were continuously examined, visually classified and
logged Logs ofthe test borings and frenches are presented on Figures A-l tiirough A-23. The logs
depict the depth and description of the various soil types encountered and include tiie deptiis which
sampling was perfonned.
ProjectNo. 06301-12-01
April 28, 1999
iFile No. D-4394-J01
July 17, 1989
BORING B 1
ELEVATION 255.0 DATE DRILLED 6/26/89
EQUIPMENT ElOO BUCKET DRILLRIG
Ui
H ii 1-
m
>• 1-
H Q: ^
go 1- Z go m m
>- °-o z i: • u an a
o z i: • u
MATERIAL DESCRIPTION
(TOPSOIL REMOVED, APPROXIMATEIY 1 1/2')
SANTIAGO FORMATION
Dense to very dense, humid, light gray,
Silty fine to coarse SANDSTONE, with
fine to medium lenses, more clayey
129.9
fine to medium more clayey, rip-up clast
N25E25S contact
'Very den"se,"srightiy"moist," gray.
Clayey fine to medium .'SANDSTONE
126.7
'Ve"ry den"se,~humid,light gray, Silty
fine to coarse .SANDSTONE
becomes moist -7/10"
129.1
129.0
125.2
Figure A-l. Log of Test Boring B 1
• SAHPLIMG UNSUCCHSSFUL B ... STANDARD PENETRATIOM TEST •
S ... OISmRBED OR BAG SAMPLE S ... CHUHIC SAHPIE X
7.5
7.2
6.4
9.3
9.0
SAMPLE SYMBOLS
DRIVE SAMPLE (UNDISTURBED)
WATER TABLE OR SEEPAGE
nnliM onlv at the gpeeifie boring or trench location and
I ile No. D-4394-J01
July 17, 1989
t
i
DEPTH
IN
FEET
i
i
i
SAMPLE
NO.
>• a o _i o
X
SOIL
CLASS
(USCS)
32 -
- 34 -
36 -
38 -
40 -
- 42 -
- 44 -
46 -
Bl-7
SM
CL
ML
SM
BORING B 1
ELEVATION 255.0 DATE DRILLED 6/26/89
EQUIPMENT ElOO BUCKET DRILLRIG
MATERL^L DESCRIPTION
; UJ >-1-
H
UJ,
a
\ii
IT -
H Z
in UJ
H (-o z E o u
sfight seepage
"Very stiff, moist, yellowish brown,
Silty ri.AYSTGNE. lense shiny
fractures, m fine to coarse silty
sandstone
Hard, moist, yellowish brown, Sandy
.SILTSTONE, with some ciay
Verv dense, slightly moist, light gray, _
Silty fine to medium .SANDSTONE, micaceous
contact generally horizontal
'Ve'r^ itTff,'moiit: brown," Silty CT.AY'STONE,
shiny fractures
105.3 20.2
Figure A-2, Log of Test Boring B 1
• ... SAMPLING UHSUCCESSRiL C - STANDARD PENETRATION TEST
^ OIsmRBED OR BAG SAMPLE S ... CHUNK SAMPLE SAMPLE SYMBOLS
DRIVE SAMPLE (UNDISTURBED)
WATER TABLE OR SEEPAGE
at the date indicat«i. It ia not warranted to De repre.
D-4394-J01
1989
SAMPLE
NO.
BORING B 1
ELEVATION 255.0 DATE DRILLED 6/26/89
EQUIPMENT ElOO BUCKET DRILLRIG
S UJ Q M . M " l-
<t S N
Z S UJ ^ ca
UJ
UJ ir -D y-
h- Z
in Ui
o z z. o u
MATERIAL DESCRIPTION
I- 60
62 -
64
BI-11
66
few shiny surfaces
CL
Very dense, slightiy moist, light gray,
Silty fine to medium .SANDSTONE
BORING rERMlNAl'iiD AT bb.U i-'iiii
' Z . „ onlv at the ipecific boring or trench location and
I 'File No,
July 17,
D-4394-J01
1989
BORING B 2
ELEVATION 232.0
EQUIPMENT
DATE DRILLED 6/26/89
vmn BUCKET DRILLRIG
SUJ
H a 1-
^ S q
UJ ta
I-
>°-Q: a
MATERIAL DESCRIPTION
COLLUVIUM
CL I Hard, moist, brown, very Sandy CLAJL
"oenJe'humid, brown. Clayey fine to coarse
SAND
SANTIAGO FORMATION
Very dense, moist, very pale brown, shghtiy
Qayey fine to coarse SAND.STQNE
clayey fine to medium sandy layer
N20E5SE
Clayey rip-up clasts, becomes light
gray, micaceous
N30E10N wavy, could expect seepage
Hard, moist, yellowish brown, Sandy
SILTSTONE, with some clay, carbon
flecks
gradational
Very dense, moist, yellow brown, Silty fine
to Sarse SANDSTONE, with layers of sandy
siltstone
dipping contact
sandy siltstone
fault N50W65S fracmred zone 1" wide,
slightly remolded
Ward, moist. ^'"""^ hrnwn. Sandy
124.5
123.8
UJ
a »
H Z tn UI M H o z i: o o
7.8
7.2
IT
111.5 18.7
Figure A-4, Log of Test Boring B 2 ,,„O,STURBED)
5 -—^...na UNSUCCESSFUL B ... STANDARD PENETRATION TEST 1 ... ^^^^^^^
SAMPLE SYMBOLS ^ pismRBED OR BAG SAMPLE S ... CHUNK SAMPLE ? - ^
tile No. D-4394-J01
July 17, 1989
i
I
i
i
I
i
i
t
EPTH
IH
FEET
SAMPLE
NO.
32 -
34 -
36 -
38 -
40 -
42 -
44 -
46 -
B2-5
B2-6
SOIL
CLASS
(USCS)
ML
"SM"
CL
CL
BORING B 2
ELEVATION 232.0
EQUIPMENT ^
DATE DRILLED 6/26/89
ElOO BUCKET DRILLRIG
: Ul
MATERL\L DESCRIPTION
Witn some ciay
fracmred zone, shiny parting surfaces
approximately 4 " wide, roughly honzontal
Very dense, moist, light gray, Silty
fine to coarse SANDSTONE
10
"H^d,"mJis"t," p^e' olive,'Sifty ri.AYSTONE
with some sand, few shiny surfaces
•Hard,"mo"is't,' brown,'s"ilty CLAYSTONE,
shiny fracture surfaces
BORING TERMINATED AT 47.0 FEET
Ul r;
Ul tr « 3 I->- z U) Ui M H o z E O u
"nrr
110.1 19.4
figure A-5. Log of Test Boring B 2
• ... SAMPLING UNSUCCESSFUL
DISTURBED OR BAG SAMPLE
C ... STANOARD PENETRATION TEST
a ... CHUNK SAMPLE SAMPLE SYMBOLS ^
DRIVE SAMPLE (UNOIsmRBED)
... WATER TABLE OR SEEPAGE
I File No. D-4394-J01
July 17, 1989
DEPTH
IN
FEET
SAMPLE
NO.
t
i
2 -
4 -
,1-8 -
B3-1
SOIL
CLASS
(USCS)
j- 10
r
- 14
- 16 -
- 18 -
- 20 -
- 22 -
24 -
- 26 -
- 28 -
B3-2
B3-3
B3-4
B3-5
B3-6
CL
SC
BORING B 3
PT.EVATION 215.0
EQUIPMENT
DATE DRILLED 6/27/89 |S in
ElOO BUCKET DRILLRIG
MATERL\L DESCRIPTION
^^^^ose, damp, gray, Sandy CLAY
SM
COLLUVIUM TTTTv
Hard, shghtly moist, Sandy CLAY,
porous
•SA>rnAGO FORMATION
Dense to very dense, humid, hght yeUow
brown, slightly Clayey fine to coarse
SANDSTONE, with clasts of brown
claystone, weathered sandstone
claystone lense
siltstone lense
"Ve'r^ dense,"sriihtry"mo"is"t," 'Vh^ iray
sfightiy Silty fine to coarse SANDSTONE
clayey lense
CL
becomes moist
medium to coarse
few claystone lenses
becomes very pale yellow brown with
pebbles
contact: N35E5W
Very stiff, moist, brown, Sandy
r T.A YSTONE .
slightiy weathered with contact, could
be areas of seepage in future, non-
continuous shiny parting surfaces, some
dipping out of slope
p;p„rp A-6. Log of Test Boring B 3
• SAMPLING UNSUCCESSFUL
. DIsmRBED OR BAG SAMPLE
a "
>-
a
o
UJ Q: .. 3 y-I- z in UJ
H I-
o z E O U
122.9
177 7, I S.S
7.2
126.3 9.8
127.1
113.4
10.1
17.3
SAMPLE SYMBOLS
C... STANDARD PENETRATIOM TEST
a ... CHUNK SAMPLE
DRIVE SAMPLE (UNDISTURBED)
WATER TABLE OR SEEPAGE
— "~ ,. .„ fu. goecific boring or trench location and
Note: The lo, .ubeurface condition^ho- h^^^^^^^ ,„d t.n....
at the date indicated. It i. not warranted to o
I iFile No. D-4394-J01
July 17, 1989
DEPTH
IN
FEET
SAMPLE
NO.
SOIL
CLASS
(USCS)
BORING B 3
ELEVATION 215.0 DATE DRILLED 6/27/89 a
EQUIPMENT ElOO BUCKET DRILLRIG
u.
H23
30
32
34
36 -
1-38 -
B3-9
44 -
46 -
L
48 -
t
[
50 " B3-10
B3-11
CL
SM
CL
weathered zone
Very dense, sUghtly moist, pale yellowish
brown, SUty fine to medium SANDSTONE, with
some clay and coarse grains
becomes pale yellowish brown mottled with
blue
Very stiff to hard, moist, brown, Silty
CLAYSTONE, few shiny surfaces
weathered, fracmred
~ 8 118.8 15.6
shiny parting surfaces, few fractures
filled with gypsum
fracture N5W20W
becomes brown, occasional mottied
with green
becomes very sandy, mottied with gray
blue in places
116.3 15.5
- 13 106.6 20.8
Li... SAMPLING UHSUCUiaarui. -J -
SAMPLE SYMBOLS ^ QISTURBED OR BAG SAMPLE 8 ... CHUNK SAMPLE
DRIVE SAMPLE (UNOISmRBED)
WATER TABLE OR SEEPAGE
I'iie No. D-4394-J01
July 17, 1989
I
k
i
i
i
i
i
i
DEPTH
IN
FEET
60
62
SAMPLE
NO.
>-a o -I o
X
SOIL
CUSS
(USCS)
BORING B 3
ELEVATION 215.0 DATE DRILLED 6/27/89
EQUIPMENT, ElOO BUCKET DRILLRIG
z
W a t-UJ
it S \
MATERIAL DESCRIPTION
Very dense, moist, yellowisn orown
tn ^
a.
>
H guI
go
X
a
X m ce. « 3 J-I- Z
in Ul
H I-o z E o u
64 -
66 -
68 -
70
SC
SM
mottled with gray blue, Qayey fine
to medium SANDSTONE, with some silt,
micaceous
siltstone lense
"Very dense,~humi(r, pale gray, Silty
fine to coarse SANDSTONE
118.7 14.7
123.0 11.2
BORING TERMINATED AT 70.0 FEET
B... STANDARD PENETRATIOM TEST
a ... CHUNK SAMPLE 2
DRIVE SAMPLE (UNDISTURBED)
WATER TABLE OR SEEPAGE
— . onlv at the ipeeifie boring or trench location and
File No. D-4394-J01
July 17, 1989
DEPTH
IN
FEET
SAMPLE
NO.
SOIL
CLASS
(USCS)
BORING B 4
ELEVATION 229.0 DATE DRILLED 6/27/89
EQUIPMENT ElOO BUCKET DRILLRIG
UJ
H23
UI S P
UJ Q:
>•
H
SuI
go
cr a
UJ
cr « 3 I-h- Z
in Ul
o z E O U
MATERIAL DESCRIPTION
- 0
B4-1
- 2 -
- 4
- 6 -
- 8 -
10 -
12
- 14 -
- 16
- 18 -
- 20
- 22
- 24
B4-2
CL
B4-3
B4-4
B4-5
TOPSOIL
Hard, slightly moist, gray, Sandy
CLAY, porous
CL SANTIAGO FORMATION
Stiff, moist, yellow brown, Silty
(7LAYST0NE. weathered
SM
Very dense, humid, pale yellowish brown,
Silty fine to coarse .SANDSTONE with some
clay
CL-SC
could have seepage with increased
irrigation. Contact N15E10N
SC
"Very stiff, moist, yeilowish brown, very
sanely fine to coarse CLAYSTONE. weatiiered
shining parting surfaces
"Ve"ry dense,~srightiy"mols"t," yetiowSh
brown. Clayey fine to coarse SANDSTONE
SM
'Very dense, moist, very pale yeilowish
brown, Silty fine to coarse SANDSTONE
with some ciay
128.3 8.8
123.6 6.7
118.6 5.8
130.3 8.1
SAMPLE SYMBOLS
! . u.«-„ annliea only at the specific boring or trench location aad
Note: The log^"^-jf "/.."J'^f^^.^^J^^^^^^ at other location, and time..
I File No. D-4394-J01
July 17. 1989
i
BORING B 4
PT.F.V ATION 229.0
EQUIPMENT
DATE DRILLED 6/27/89
H 5 u.
<t £ \
T^inn BUCKET DRILLRIG ujl^m
MATERIAL DESCRIPTION
seepage
Very stiff, moist, gray-brown, Silty
O.A YSTONE. fracmred witii shiny
surfaces, discontinuous joint surfaces
M
gti
vo-ir a
126.3 9.0
>5
UJ tr 3 H
1- Z V) UJ H t-O Z E O O
Very stiff to hard, moist, yellowish
brown, Sandy CLAYSTONE
becomes very sandy
'Ve'n^denseVmoist, light gray, Silty fine to
medium SANDSTONE, micaceous
BORING TERMINATED AT 50.0 FEET
14
A-IQ. Log of Test Boring B 4
' ... SAMPLING UNSUCCESSFUL
SAMPLE SYMBOLS ^" ^jj^^ggn BAG SAMPLE
B... STANDARD PENETRATION TEST • ... OR.VE SAMPLE (UNDISTURBED)
a... CHUNK SAMPLE X ... WATER TABLE^RJEEPAGE_
— •" ,. .„ ,t fU. soecific boring or trench location and
at the date indicated. It i. not warranted to oe rep
lile No. D-4394-J01
July 17. 1989
i
t
i
i
DEPTH
IN
FEET
2 -
4 -
SAMPLE
NO.
Tl-l
> a a J o X H H -i
SOIL
CLASS
(USCS)
TRENCH. T 1
ELEVATION 142.0
EQUIPMENT
DATE DRILLED 6/23/89
555JP BACKHOE
MATERIAL DESCRIPTION
^Ing
u.
i-
M
in
go >-°-tr a
m
tr -3 1-1- z tn Ui
H H o z r o o
m 1 ML
HLL
Dense, humid, gray, Silty fine to coarse
SAND
SANTIAGO bORMAllUN
Hard, slightly moist, pale brown. Clayey
•Sn.TSTONE. with some fine sand, jointed
TRENCH TERMINATED AT 5.0 FEET
(DEFHCULT DIGGING)
129.4
A-ll. Log of Test Trencn i x
Q... SAMPLING UMSUCCESSFUL
, DISmRBED OR BAG SAMPLE SAMPLE SYMBOLS
B..
a..
STANDARD PEKETRATIOM TEST ORIVE SAMPLE (UNDIsmRBED)
CHUNK SAMPU r... WATER TABLE OR SEEPAG_^
File No. D-4394-J01
July 17. 1989
DEPTH
IN
FEET
- 0
r
- 4 -
SAMPLE
NO.
O o _l o X 1-H -1
SOIL
CLASS
(USCS)
T2-1
SM
TRENCH T 2
ELEVATION 259.0
EQUIPMENT
DATE DRILLED 6/23/89
555JD BACKHOE
MATERIAL DESCRIPTION
COLLUVIUM , . ^ .
Dense, slightiy moist, pale grayish-brown
Silty fine to coarse SAND, witii littie
clay, trace pebbles TY H
U.
\ gul US g"
tr
o _i
CD >-°-cr a
SANTIAGO FORMATION
Very dense, humid, pale brown, Silty tine
to coarse SANDSTONE
becomes very pale brown
TRENCH TERMINATED AT 5.0 FEtT
(DIFHCULT DIGGING)
Ui
cr >
3 I-H Z
in Ui o z E o u
24.1 6.7
Pitriire A-12 Log of Test Trench T 1 ^
^-r:~™'^" ^^^^
^ DIsmRBED OR BAG SAMPLE 3 ... CHUNK SAMPLE ^
SAMPLE SYMBOLS
——— nnlv at the specific boring or trench location and
File No. D-4394-J01
July 17, 1989
- 2 -
- 4 -
6 -
DEPTH
IN
FEET
SAMPLE
NO.
>•
a _i o
X
- 10
- 12 -
T3-1
T3-2
T3-3
T3-4 1
SOIL
CLASS
(USCS)
SM
SM
ML
TRENCH T 3
ELEVATION 208.0 DATE DRILLED 6/23/89
FILL
Dense, humid, pale brown, Silty fine to
coarse SAND
3g .
H a H
^23 UJ " O
ALLUVIUM
Very dense, slightiy moist, gray, Silty
fine to medium SAND, some clay
SANTIAGO FORMATION
Hard, moist, yellow brown. Clayey
SILTSTONE. very few fine sand grains
TRENCH TERMINATED AT 13.0 FEET
(DIPnCULT DIGGING)
>• 1-
a.
113.7
Ui
tt «
3 I-K Z Ul Ui
8.7
Figure A-13, Log of Test Trench T 3
' SAMPLING UNSUCCESSmL B ... STANDARD PENETRATION ..T • ... ORIVE ^^^^^^^^
'" TsmRBED OR BAG SAMPLE 3 ... CHUNK SAMPLE XWATER TABLE ORJE^ SAMPLE SYMBOLS
"7 . .„„ii-, onlv at the .pecific boring or trench location and
Note: The log .ubeurfac. condition. J'"^" .ub.urfac. condition, at other location, and t.me..
at the daU indicated. II i. not warranted to be reprewntat.
l-ile No. D-4394-J01
July 17, 1989
i
i
i
DEPTH
IN
FEET
SAMPLE
NO.
>• a o _i o X H H J
SOIL
CLASS
(USCS)
r - 6
10 I
SM
SM
ML
TRENCH T 4
ELEVATION 218.0 DATE DRILLED 6/23/89
EQUIPMENT 555JD BACKHOE
MATERIAL DESCRIPTION
ALLUVIUM/COLLUVIUM
Dense to very dense, humid, pale brown,
Silty fine to coarse SAND
few cobbles
carbon flecks
Very dense, humid to sfightiy moist, light
gray, Silty fine to coarse SAND,
cohesionless lenses
SA>rnAGO FORMATION
Hard, slightly moist, pale olive. Clayey
.SILTSTONE with slight fine sand, jointed
TRENCH TERMINATED AT 11.0 FEET
(DIFHCULT DIGGING)
o UJ
HS3
Z^S
Ui
cr «
3 1-H Z
in Ui
o z
E O
o
Figure A-14. Log of Test Trench T 4
• . SAMPLING UNSUCCESSFUL B STANDARD PENETRATION TEST
«^ DISTURBED OR BAG SAMPLE S... CHUNK SAMPLE SAMPLE SYMBOLS
DRIVE SAMPLE (UNDISTURBED)
WATER TABLE OR SEEPAGE
", ,t thm soecific boring or trench location and
Note: The log .ubeurface condition. ^^^^'r^^l^^^^^^^^ - other location, and t.n,...
at the date indicated. It i. not warranted to be repr-en
I ile No. D-4394-J01
July 17, 1989
DEPTH
IN
FEET
SAMPLE
HO.
- 2 -
- 4 -
- 6 -
8 -
- 10
- 12 -
> a o _i o I
H
T5-1
T5-2
T5-3
SOIL
CLASS
(USCS)
TRENCH T 5
FT .EVATION 205.0
EQUIPMENT
DATE DRILLED 6/23/89
555JD BACKHOE
<t \
-S3
s in
SM
3M:
SC
ML
MATERIAL DESCRIPTION
ALLUVIUM ^
Dense, humid, dark brown-gray, Silty
medium to coarse SAND, sUghtiy
porous
becomes brown, less porous
'DenseT slightiy moist, pale brown,
Silty fine to coarse SAND, shghtiy
clayey
>•
w
gci tr a
Ui
tr -3 1-K Z
in UJ
W H o z E O
u
105.8
"De'nse"m'oIst,'b'rown,'Clayey fine to
coarse SAND
SANTIAGO FORMATION _
Hard, moist, brown, Sandy STLTSTONE
jointed
106.0
4.2
13.1
TRENCH TERMINATED AT 13.0 FEET
(DIFHCULT DIGGING)
Figure A-15. Log of Test Trench T 5
• ... SAMPLING UNSUCCESSFUL C •
DISTURBED OR BAG SAMPLE SAMPLE SYMBOLS a..
STANDARD PENETRATION TEST
CHUNK SAMPLE
DRIVE SAMPLE (UNDISTURBED)
WATER TABLE OR SEEPAGE
II • !•„ i„ .t tha soecific boring or trench location and
Note: The log .ub.urface condition, 'h"- he«o^^^^^^^^^^^ condition, at other location, and time.,
at th. date indicated. II i. not warr«ted to be repr«.«,
IFIIC NO. D-4394-J01
July 17. 1989
i
i
DEPTH
IN
FEET
- 4 -
- 6 -
8 -
- 10
- 12 -
- 14 -
- 16 -
SAMPLE
NO.
T6-1
SOIL
CLASS
(USCS)
CL
SM
TRENCH T 6
ELEVATION 195.0 DATE DRILLED 6/23/89
Ui
<t i \
EQUIPMENT. 555JD BACKHOE
Ui
iu|"n
MATERIAL DESCRIPTION
u. go
>-°-cr a
ALLUVIUM ^
Dense, humid, brown, Silty fine to
coarse SAND with humus
"Hard,"siiihtry"moistr dark gray brown,
very Sandy CLAY, sfightiy porous
"Dense" slightly "moist to' moist, pale
brown, Silty fine to coarse SAND,
mottied appearance
UJ tr « 3 H 1- z in Ui
o z E O O
100.8 11.6
ML
SANTTAGO FORMATION
Stiff, very moist, pale brown, Sandy
sn.TSTONE
TRiNCH ILRMlNAiED AT l/.U ftii
Figure A-16, Log of Test Trench T 6
• . SAMPLING UNSUCCESSFULB ... STANDARD PENETRATION TEST
" DISTURBED OR BAG SAMPLE 3 ... CHUNK SAMPLE SAMPLE SYMBOLS
... DRIVE SAMPLE (UNDISUIRBED)
X... WATER TABLE OR SEEPAGE
at the date indicated. It i. not warrants! to be repr..-
I File
July
No. D-4394-J01
17. 1989
DEPTH
IN
FEET
- 0
- 2 -
- 4 -
6
8
10
SAMPLE
NO.
> a o _i o
X
T7-1
TRENCH T 7
SOIL I
CLASS ELEVATION,
(USCS)
EQUIPMENT
195.0 DATE DRILLED 6/23/89
555JD BACKHOE
SC
CL
SM
MATERIAL DESCRIPTION
^°DeS?h!^id, black, sfightiy Clayey
fine to coarse SAND
becomes more clayey
SANTIAGO FORMATION
Very stiff, moist, tan mottied with
black, Sandy CLAY, witii trace pebbles
contact wavy
Ui
law : S \ in in
Ui
Ui ;
Very dense, sfightiy moist, very pale
brown, Silty fine to medium SAND.
micaceous
TRENCH TERMINATED AT 10.0 FEET
(DIFHCULT DIGGING)
16.4
c;^...l A-17. Log of Test Trencn i i
• SAMPLING UNSUCCESSFUL
. DISTURBED OR BAG SAMPLE SAMPLE SYMBOLS
B ... STANDARD PENETRATIOM TEST
a ... CHUNK SAMPLE
ORIVE SAMPLE (UNOISmRBED)
.. WATER TABLE OR SEEPAGE
• „i„ ,t tha soecific boring or trench location and
Note: The log .ub.urface -dition^^^-^'-^^^^^ .t other location, and tune.,
atthe date indicated. It i. not warranted to o.
I ''ile No. D-4394-J01
July 17, 1989
Figure A-18J^^
SAMPLE SYMBOLS SAMPLE 3 ... CHUNK SAMPLE
at the date indicated. It.. not warrantee
DRIVE SAMPLE (UNDISTURBED)
WATER TABLE OR SEEPAGE
File No. D-4394-J01
July 17, 1989
DEPTH
IN
FEET
- 0
SAMPLE
NO.
4 -
6 -
8 -
10 -
12 -
14 -
T9-1
- 16
TRENCH T 9
SOIL ,
CLASS ELEVATION,
(USCS) I
EQUIPMENT
182.0 DATE DRILLED 6/23/89
555JD BACKHOE
SM
SC
MATERIAL DESCRIPTION
COLLUVIUM , , ^,
Dense, humid, dark gray, shghtiy Clayey
fine to medium SAND, porous
ALLUVIUM , .
Very dense, humid, very pale brown,
Silty fine to coarse SAND, mottied,
roots, layers of hunuc material
becomes less mottled, few lenses of
fine to medium sand
carbon flecks
Very dense, moist, brown. Clayey fine
to coarse SAND, mottled with roots
SANTIAGO FORMAIION
Very dense, moist, pale brown. Clayey
fine to coarse SANDSTONE
"Ha"rd,"moist. pale brown, Sandy SILTSTONE
TRENCH TERMINATED AT 16.0 FEET
(DIFHCULT DIGGING)
Ui
O I
u.
UJ S P
Ui Ui ta
H guI
liio >•' cr a
Ui
tr ~ 3 t-I- Z in Ui H H o z E O o
101.8 6.3
Figure A-19, Log of Test Trench T 9
• ... SAMPLING UNSUCCESSFUL
DISmRBED OR BAG SAMPLE SAMPLE SYMBOLS
B ... STANDARD PENETRATION TEST
a ... CHUNK SAMPLE
DRIVE SAMPLE (UNDISTURBED)
WATER TABLE OR SEEPAGE
——— ' "• i:..- „nlw at the .pecific boring or trench location and
Note: The log .ub.urfac. condition. •'>»J°fbrr^'^TatWe of .ub.urface condition, at other location, and t.me..
at the date indicated. It i« not warranted to oe r«p
ile No. D-4394-J01
July 17, 1989
DEPTH
IN
FEET
SAMPLE
NO.
TRENCH T 10
ELEVATION 164.0
EQUIPMENT
DATE DRILLED 6/23/89
555JD BACKHOE
Ui
H
gti
>^ tr a
Ui
cc »
3 I-I- Z in Ui
H y-o z E O U
- 0
- 2 -
4 -
6 -
8 -
10 -
12
14
TlO-1
MATERIAL DESCRIPTION
FILL
Loose, damp, fight gray, sfightiy Silty
fine to coarse SAND
REWORKED ALLUVIUM
Very stiff, moist, dark gray, Sandy
CLAY
pipe
ALLUVIUM
Very stiff, moist, pale brown, very
Clayey SILT
SAKITAGO FORMATION
Very dense, moist, blue-gray and pale
brown. Clayey fine to coarse SANDSTUNb,
with roots
• TRENCH TERMINATED AT 14.0 irhhl
(DIFHCULT DIGGING)
101.6 17.7
Figure A-20, Log of Test Trench T 10
^ • SAMPLING UNSUCCESSFUL B ... STANDARD PE.ETRAT I OM TEST • ... ORIVE SAMPLE (UNDISTURB.)
m rSTURSEP OR BAG SAMPLE B ... CHUNK SAMPLE T ... WATER TABLE OR SEEPA^
'—• '—' I . „ onlv at the .pecific boring or trench location and
SAMPLE SYMBOLS
ile No. D-4394-J01
July 17. 1989
TRENCH T 11
SOIL ,
CUSS ELEVATION, 232.0 DATE DRILLED 6/26/89
EQUIPMENT 555JD BACKHOE
MATERIAL DESCRIPTION
Hard, slightiy moist, gray, Sandy CLAY.
porous
" "Very stif?,"moist7 brown," Sandy CLAY,
faint odor
H23 ^InO
SANTIAGO FORMATION
Dense, moist, gray mottled with orange
Clayey fine to coarse SANDSTONE
becomes gray, very dense
becomes dark gray, moist
'very dense, slightiy moist, light gray,
Silty fine to coarse SANDSTONE
"TRENCH TERMINATED AT 14.0 FEEI
(DIFHCULT DIGGING)
H
go
tr
•
Ui
tr -3 I-H Z Ul Ui H I-
o z
E O U
SAMPLE SYMBOLS
• • ~ , .„„ii«- onlv at the .pecific boring or trench location and
Note: The log .ubeurface condition, .hown ^'f^'J^^^^i^^^t .ub.urfac condition, at other location, and t.m... at the date indicated. It i. not warranted to be repre«ai
I lile No. D-4394-J01
July 17. 1989
TRENCH- T 12
ELEVATION 223.0
EQUIPMENT .
DATE DRILLED 6/26/89
555JD BACKHOE
MATERIAL DESCRIPTION
COLLUVIUM _ ,
Hard, moist, dark brown, very Sandy
CLAY, porous
SANTLAGG FORMA IION
Very dense, humid, very pale brown,
SUty fine to coarse SANDSTONE
Very dense, sfightiy moist, yellowish brown.
Clayey fine to coarse SANDSTONE
TRENCH TERMINATED AT 13.0 FEET
^23
tL
IU.
>-I-H S,
gd
>-°-
tr a
Ui
tr « 3 H H Z
m Ui o z E a o
Figure A-22, Log of Test Trench T12
•^..S^pUNa UNSUCCESSFUL B - STANDARD PENETRATION TEST
i... DISTORBED OR. BAG SAMPLE SAMPLE SYMBOLS a ... CHUNK SAMPLE
1... DRIVE SAMPLE (UNDIsmRBED)
r... WATER TABLE OR SEEPAGE^
_____ ^ — ^ o-iy at the .pecific boring or trench location and
Note: Th. log .ub.urface condition. •'»-",„^^„V^tTa^^^^^^^ .ubeuSl. condition, at other locat.on. and t.m...
at the date indicated. It i. not warranted to be rep
File No.
July 17,
D-4394-J01
1989
DEPTH
IN
FEET
SAMPLE
HO.
> ts o -I o
X
I-
TRENCH T 13 cr UJ »-<t 3
Q
3 (USCS) ,
g EQUIPMENT
SOIL ,
CLASS ELEVATION, 206.0 DATE DRILLED 6/26/89
555JD BACKHOE
; Ui
I o.
«t \
z«3
>-
H
go
>-°-tr
Q
Ui tr > 3 1-y- z in Ul M H o z EO o
- 0
- 2
- 4
- 6
- 8
10
12
T13-1
CL
3M-MI
SC
SM
MATERIAL DESCRIPTION
COLLUVIUM
Hard, sfightiy moist, dark brown, very
Sandy CLAY, porous
SANTIAGO FORMATION
Very stiff, moist, pale brown and brown
layers of Sandy SILTSTONE and very
Silty fine to medium SANDSTONE
Very dense, sfightiy moist to moist,
pale gray and brown. Clayey fine to
coarse SANDSTONE witii carbon
106.9
"Very dense, slightiy moist, pale brown,
Silty fine to coarse SANDSTONE
becomes cobbly
14.7
TRENCH. TERMINATED AT 12.0 FEET
(DIFHCULT DIGGING)
Figure A-23. Log, of Test Trench^ T13
• SAMPLING UNSUCCESSFUL. B
. DISTURBED OR BAG SAMPLE SAMPLE SYMBOLS ^3 • <
STANDARD PENETRATIOM TEST
CHUNK SAMPLE
DRIVE- SAMPLE (UNOISmRBED)
WATER TABLE OR SEEPAGE
^ " " 7 .„.:-, onlv at the .pecific boring or trench location and
Note: The log .ubeurfac. condition. ''•/~"_^Tative of .ubeurface condition, at other location, and t.me..
at the daU indicat«l. It i. not warranted to D« rep
J • r.V:.- ••• -.•) •
APPENDIX ^
•'•L-.:J.-.
APPENDIX B
LABORATORY TESTING
Laboratory tests were perfomied in accordance with generally accepted test methods ofthe American
Society for Testing and Materials (ASTM) or other suggested procedures. Selected relatively
undisturbed samples were tested for their in-place dry density, moismre content, shear sfrength, and
expansion potential.
The maximum dry density and optimum moismre content of selected bulk samples were detemiined
in accordance with ASTM Test Procedure D1557-78, A. Portions of the bulk samples were then
remolded to selected densities and subjected to direct shear tests and expansion tests. Direct shear
tests, and expansion tests were also perfonned on relatively undismrbed samples.
The results of our laboratory tests are presented in tabular fomi herein. The in-place density and
moismre characteristics are also presented on the logs ofthe test borings and trenches.
TABLE B-l ^
SUMMARY OF LABORATORY MAXIMUM DRY DENSIPT
AND OPTIMUM MOISTURE CONTENT TEST RESULTS
ASTM D 1557
•sample remolded to approrimately 90 percen, relative density a. near optimum moismre content
ProjectNo. 06301-12-01
TABLE B-III
SUMMARY OF LABORATORY EXPANSION INDEX TEST RESULTS
Sample
No.
Moisture Content Dry
Density (pcf)
Expansion
Index Sample
No. Before Test (%) After Test (%)
Dry
Density (pcf)
Expansion
Index
Bl-10 11.3 27.3 105 93
Project No. 06301-12-01 •B-2-
APPENDIX
APPENDIX C
RECOMMENDED GRADING SPECIFICATIONS
for
SPYGLASS
CARLSBAD, CALIFORNIA
PROJECT NO. 06301-12-01
RECOMMENDED GRADING SPECIFICATIONS
1. GENERAL
1.1. These Recommended Grading Specifications shall be used in conjunction with the
Geotechnical Report for the project prepared by Geocon Incorporated. The recom-
raendations contained in the text of the Geotechnical Report are a part of the earthwork and
grading specifications and shall supersede the provisions contained hereinafter in the case
of conflict.
1.2. Prior to the commencement of grading, a geotechnical consultant (Consultant) shall be
employed for the purpose of observing earthwork procedures and testing the fills for
substantial confonnance with tiie recommendations of the Geotechnical Report and these
specifications. It will be necessary that the Consultant provide adequate testing and
observation services so that he may determine that, in his opinion, the work was performed
in substantial conformance with these specifications. It shall be the responsibility of the
Confractor to assist the Consultant and keep him apprised of work schedules and changes
so tiiat personnel may be scheduled accordingly.
1.3. It shall be the sole responsibility of the Contractor to provide adequate equipment and
methods to accomplish the work in accordance with applicable grading codes or agency
ordinances, these specifications and the approved grading plans. If in the opinion of the
Consultant, unsatisfactory conditions such as questionable soil materials, poor moismre
condition, inadequate compaction, adverse weather, and so forth, result in a quality of work
not in conformance with these specifications, the Consultant will be empowered to reject
the work and recommend to tiie Owner that constmction be stopped until the unacceptable
conditions are conected.
2. DEFINITIONS
2.1. Owner shall refer to the owner of the property or the entity on whose behalf the grading
work is being performed and who has confracted with the Confractor to have grading
performed.
2.2. Contractor shall refer to the Contractor performing the site grading work.
2.3. Civil Engineer or Engineer of Work shall refer to the Califomia licensed Civil Engineer
or consulting firm responsible for preparation of the grading plans, surveying and verifying
as-graded topography.
GI rev. 8/98
2.4. Consultant shall refer to the soil engineering and engineering geology consulting firm
retained to provide geotechnical services for the project.
2.5. Soil Engineer shall refer to a Califomia licensed Civil Engineer retained by the Owner,
who is experienced in the practice of geotechnical engineering. The Soil Engineer shall be
responsible for having qualified representatives on-site to observe and test the Contractor's
work for conformance with these specifications.
2.6. Engineering Geologist shall refer to a Califomia licensed Engineering Geologist retained
by the Owner to provide geologic observations and recommendations during the site
grading.
2.7. Geotechnical Report shall refer to a soil report (including all addenda) which may include
a geologic reconnaissance or geologic investigation that was prepared specifically for the
development of the project for which tiiese Recommended Grading Specifications are
intended to apply.
3. MATERIALS
3.1. Materials for compacted fill shall consist of any soil excavated fi-om the cut areas or
imported to the site that, in tiie opinion ofthe Consultant, is suitable for use in constmction
of fills. In general, fill materials can be classified as sod fills, soil-rock fills or rock fills, as
defmed below.
3.1.1. Soil fills are defined as fills containing no rocks or hard lumps greater than 12
inches in maximum dimension and containing at least 40 percent by weight of
material smaller than 3/4 inch in size.
3.1.2. Soil-rock fills are defined as fills containing no rocks or hard lumps larger tiian 4
feet in maximum dimension and containing a sufficient matrix of soil fill to allow
for proper compaction of soil fill around the rock fragments or hard lumps as
specified in Paragraph 6.2. Oversize rock is defined as material greater than 12
inches.
3.1.3. Rock fills are defined as fills containing no rocks or hard lumps larger than 3 feet
in maximum dimension and containing little or no fines. Fines are defined as
material smaller than 3/4 inch in maximum dimension. The quantity of fines shall
be less than approximately 20 percent of the rock fill quantity.
Gl rev. 8/98
J.J.
Material of a perishable, spongy, or otherwise unsuitable nature as determined by the
Consultant shall not be used in fills.
Materials used for fill, either imported or on-site, shall not contain hazardous materials as
defined by the Califomia Code of Regulations, Title 22, Division 4, Chapter 30, Articles 9
and 10; 40CFR; and any other applicable local, state or federal laws. The Consultant shall
not be responsible for the identification or analysis ofthe potential presence of hazardous
materials. However, if observations, odors or soil discoloration cause Consultant to
suspect the presence of hazardous materials, the Consultant may request from the Owner
the tennination of grading operations within the affected area. Prior to resuming grading
operations, the Owner shall provide a written report to the Consultant indicating that the
suspected materials are not hazardous as defined by applicable laws and regulations.
3 4 The outer 15 feet of soil-rock fill slopes, measured horizontally, should be composed of
properly compacted sod fill materials approved by tiie Consultant. Rock fill may extend to
the slope face, provided that the slope is not steeper than 2:1 (horizontahvertical) and a soil
layer no thicker than 12 inches is track-walked onto the face for landscaping purposes.
This procedure may be utilized, provided it is acceptable to the goveming agency. Owner
and Consultant.
3 5 Representative samples of soil materials to be used for fill shall be tested in the laboratory
by the Consultant to detennine tiie maximum density, optimum moismre content, and,
where appropriate, shear sfrength, expansion, and gradation characteristics ofthe soil.
3 6 During grading, soil or groundwater conditions other than those identified in tiie
Geotechnical Report may be encountered by the Confractor. The Consultant shall be
notified immediately to evaluate the significance ofthe unanticipated condition
4. CLEARING AND PREPARING AREAS TO BE FILLED
4 1 Areas to be excavated and filled shall be cleared and gmbbed. Clearing shall consist of
complete removal above the ground surface of trees, smmps, bmsh, vegetation, man-made
Sfrucmres and similar debris. Gmbbing shall consist of removal of smmps, roots, buned
logs and other unsuitable material and shall be perfomied in areas to be graded. Roots and
other projections exceeding 1-1/2 inches in diameter shall be removed to a deptii of 3 feet
below the surface ofthe ground. Bonow areas shall be gmbbed to the extent necessary to
provide suitable fill materials.
4.2. Any asphalt pavement material removed during clearing operations should be properly
disposed at an approved off-site facility. Concrete fragments which are free of reinforcing
steel may be placed in fills, provided they are placed in accordance with Section 6.2 or 6.3
of this document.
4.3. After clearing and gmbbing of organic matter or other unsuitable material, loose or porous
soils shall be removed to tiie depth recommended in tiie Geotechnical Report. The deptii of
removal and compaction shall be observed and approved by a representative of tiie
Consultant. The exposed surface shall tiien be plowed or scarified to a minimum depth of
6 inches and until tiie surface is free from uneven feamres tiiat would tend to prevent
uniform compaction by the equipment to be used.
4 4 Where tiie slope ratio of the original ground is steeper than 6:1 (horizontahvertical), or
where recommended by the Consultant, the original ground should be benched m
accordance witii the following illusfration.
TYPICAL BENCHING DETAIL
Finish Grade Original Ground
Finish Slope Surface
Remove All
Unsuitable Material
As Recommended By
Soil Engineer Slope To Be Such That
Sloughing Or Sliding
Does Not Occur
•B'
See Note i See Note 2
No Scale
DETAIL NOTES:
modified as approved by the Consultant.
4.5. After areas to receive fill have been cleared, plowed or scarified, the surface should be
disced or bladed by the Contractor until it is unifonn and free from large clods. The area
should then be moismre conditioned to achieve the proper moismre content, and compacted
as recommended in Section 6.0 of these specifications.
5. COMPACTION EQUIPMENT
5 1 Compaction of sod or soil-rock fill shall be accomplished by sheepsfoot or segmented-steel
wheeled rollers, vibratory rollers, multiple-wheel pneumatic-tired rollers, or other types of
acceptable compaction equipment. Equipment shall be of such a design that it will be
capable of compacting the sod or soil-rock fill to the specified relative compaction at the
specified moisture content.
5.2.
6.1.
Compaction of rock fills shall be perfomied in accordance witii Section 6.3.
6. PLACING, SPREADING AND COMPACTION OF FILL MATERIAL
Sod fill, as defined in Paragraph 3.1.1, shall be placed by the Confractor in accordance witii
the following recommendations:
6 1 1 Sod fill shall be placed by the Confractor in layers that, when compacted, should
generally not exceed 8 inches. Each layer shall be spread evenly and shall be
thoroughly mixed during spreading to obtain unifomiity of material and moisture
in each layer. The entire fill shall be consfructed as a unit in nearly level lifts.
Rock materials greater than 12 inches in maximum dimension shall be placed m
accordance with Section 6.2 or 6.3 of these specifications.
6.1.2. In general, the sod fill shall be compacted at a moismre content at or above the
optimum moismre content as detennined by ASTM D1557-91.
6 1 3 When the moismre content of sod fill is below that specified by the Consultant,
water shall be added by the Confractor unfil the moismre content is in the range
specified.
When the moismre content of the sod fill is above the range specified by the
Consultant or too wet to achieve proper compaction, the sod fill shall be aerated by
the Confractor by blading/mixing, or other satisfactory metiiods until tiie moismre
content is within the range specified.
6.1.4.
6.1.5. After each layer has been placed, mixed, and spread evenly, it shall be thoroughly
compacted by the Confractor to a relative compaction of at least 90 percent.
Relative compaction is defined as the ratio (expressed in percent) of the in-place
dry density of the compacted fill to the maximum laboratory dry density as
detennined in accordance with ASTM D1557-91. Compaction shall be continuous
over the entire area, and compaction equipment shall make sufficient passes so that
tiie specified minimum relative compaction has been achieved throughout the
enfire fill.
6.1.6. Soils having an Expansion Index of greater than 50 may be used in fills if placed at
least 3 feet below finish pad grade and should be compacted at a moisttn-e content
generally 2 to 4 percent greater than the optimum moismre content for the material.
6 1 7. Properly compacted sod fill shall extend to tiie design surface of fill slopes. To
achieve proper compaction, it is recommended that fill slopes be over-buih by at
least 3 feet and then cut to the design grade. This procedure is considered
preferable to track-walking of slopes, as described in the following paragraph.
6 1.8. As an altemative to over-building of slopes, slope faces may be back-rolled with a
heavy-duty loaded sheepsfoot or vibratory roller at maximum 4-foot fill height
intervals. Upon completion, slopes should then be frack-walked with a D-8 dozer
or similar equipment, such tiiat a dozer frack covers all slope surfaces at least
twice
6.2. Soil-rockm, as defined in Paragraph 3.1.2, shall be placed by the Confractor in accordance
with the following recommendations:
6 2 1 Rocks larger than 12 inches but less than 4 feet in maximum dimension may be
incorporated into the compacted sod fill, but shall be limited to the area measured
15 feet minimum horizontally from the slope face and 5 feet below finish grade or
3 feet below the deepest utility, whichever is deeper.
6.2.2. Rocks or rock fragments up to 4 feet in maximum dimension may eitiier be
individually placed or placed in windrows. Under certain conditions, rocks or rock
fragments up to 10 feet in maximum dimension may be placed using similar
methods. The acceptability of placing rock materials greater than 4 feet m
maximum dimension shall be evaluated during grading as specific cases anse and
shall be approved by the Consultant prior to placement.
6.2.3. For individual placement, sufficient space shall be provided between rocks to allow
for passage of compaction equipment.
6.2.4. For windrow placement, the rocks should be placed in trenches excavated in
properly compacted sod fill. Trenches should be approximately 5 feet wide and 4
feet deep in maximum dimension. The voids around and beneath rocks should be
filled with approved granular soil having a Sand Equivalent of 30 or greater and
should be compacted by flooding. Windrows may also be placed utilizing an
"open-face" metiiod in lieu ofthe french procedure, however, this metiiod should
first be approved by the Consultant.
6.2.5. Windrows should generally be parallel to each other and may be placed either
parallel to or perpendicular to tiie face of tiie slope depending on tiie site
geomefry. The minimmn horizontal spacing for windrows shall be 12 feet
center-to-center witii a 5-foot stagger or offset from lower courses to next
overlying course. The minimum vertical spacing between windrow courses shall
be 2 feet from the top of a lower windrow to tiie bottom of tiie next higher
windrow.
6 2 6 All rock placement fill placement and flooding of approved granular soil in the
windrows must be continuously observed by tiie Consultant or his representative.
6.3. Rockmis, as defined in Section 3.I.3., shall be placed by the Contractor in accordance with
the following recommendations:
6 3 1 The base of the rock fill shall be placed on a sloping surface (minimum slope of 2
peroent, maximum slope of 5 percent). The surface shall slope toward suitable
subdrainage outlet facilifies. The rock fills shall be provided with subdrains dunng
consfruction so that a hydrostatic pressure buildup does not develop. The
subdrains shall be pemianentiy connected to confrolled drainage facilities to
confrol post-constmction infiltration of water.
6 3 2 Rock fills shall be placed in lifts not exceeding 3 feet. Placement shall be by rock
• • • tmcks traversing previously placed lifts and dumping at the edge of tiie cunentiy
placed lift. Spreading ofthe rock fill shall be by dozer to facilitate seating ofthe
rock The rock fill shall be watered heavily during placement. Watenng shall
consist of water frucks fraversing in front ofthe cunent rock lift face and spraying
water continuously during rock placement. Compaction equipment witii
compactive energy comparable to or greater than tbat of a 20-ton steel v.bratoo^
roller or other compaction equipment providing suitable energy to achieve the
required compaction or deflection as recommended in Paragraph 6.3.3 shall be
utilized. The number of passes to be made will be detennined as described in
Paragraph 6.3.3. Once a rock fill lift has been covered with sod fill, no additional
rock fill lifts will be pennitted over the sod fill.
6.3.3. Plate bearing tests, in accordance with ASTM Dl 196-64, may be perfomied in
both the compacted soU fill and in the rock fill to aid in detennining the number of
passes of the compaction equipment to be perfonned. If perfonned, a minimum of
three plate bearing tests shall be perfonned in the properiy compacted sod fill
(minimum relative compaction of 90 percent). Plate bearing tests shall then be
perfonned on areas of rock fill having two passes, four passes and six passes ofthe
compaction equipment, respectively. The number of passes required for the rock
fill shall be detemiined by comparing die results of the plate bearing tests for tiie
sod fill and tiie rock fill and by evaluating the deflection variation with number of
passes. The required number of passes of the compaction equipment will be
perfonned as necessary until the plate bearing deflections are equal to or less than
that detemiined for the properly compacted sod fill. In no case will tiie required
number of passes be less than uvo.
6 3 4 A representative of the Consultant shall be present during rock fill operations to
verify that the minimum number of "passes" have been obtained, that water .s
being properly applied and that specified procedures are being followed. The
acmal number of plate bearing tests will be detemiined by tiie Consultant dunng
grading. In general, at least one test should be perfomied for each approximately
5,000 to 10,000 cubic yards of rock fill placed.
6 3 5 Test pits shall be excavated by the Confractor so that the Consultant can state that,
• • • in his opinion, sufficient water is present and that voids between large rocks are
properly filled with smaller rock material. In-place density testing will not be
required in the rock fills.
6 3 6 To reduce the potential for "piping" of fines into the rock fill from overiying soil
• • • fill material, a 2-foot layer of graded filter material shall be placed above the
uppemiost lift of rock fill. The need to place graded filter material below the rode
should be detemiined by the Consultant prior to commencing grading The
gradation of the graded filter material will be detemiined at the ti- ^« / he
being excavated. Materials typical of the rock fill should be submitted to the
Consultant in a timely manner, to allow design of the graded filter pnor to the
commencement of rock fill placement.
Gl rev. 8/98
Ll
6.3.7. All rock fill placement shall be continuously observed during placement by
representatives of the Consultant.
7. OBSERVATION AND TESTING
7.1. The Consultant shall be tiie Owners representative to observe and perform tests dunng
clearing, gmbbing, filling and compaction operations. In general, no more than 2 feet in
vertical elevation of sod or soil-rock fill shall be placed without at least one field density
test being perfonned witiiin that interval. In addition, a minimum of one field density test
shall be perfonned for every 2,000 cubic yards of sod or soil-rock fill placed and
compacted.
7.2. The Consultant shall perfonn random field density tests of tiie compacted sod or soil-rock
fill to provide a basis for expressing an opinion as to whether the fill material is compacted
as specified. Density tests shall be perfonned in the compacted materials below any
dismrbed surface. When these tests indicate that tiie density of any layer of fill or portion
thereof is below that specified, the particular layer or areas represented by the test shall be
reworked until the specified density has been achieved.
7 3 During placement of rock fill, the Consultant shall verify tiiat the minimum number of
passes have been obtained per the criteria discussed in Section 6.3.3. The Consultant shall
request the excavation of observation pits and may perfonn plate bearing tests on the
placed rock fills. The observation pits will be excavated to provide a basis for expressmg
an opinion as to whether the rock fill is properly seated and sufficient moismre has been
applied to the material. If perfomied, plate bearing tests will be perfomied randomly on
the surface ofthe most-recently placed lift. Plate bearing tests will be perfomied to provide
a basis for expressing an opinion as to whether the rock fill is adequately seated. The
maximum deflection in the rock fill detemiined in Section 6.3.3 shall be less than the
maximum deflection of the properly compacted sod fill. When any of the above cnteria
indicate that a layer of rock fill or any portion tiiereof is below that specified, tiie affected
layer or area shall be reworked until the rock fill has been adequately seated and sufficient
moismre applied.
7 4 A settlement monitoring program designed by the Consultant may be conducted in areas of
rock fill placement. The specific design of the monitoring program shall be as
recommended in the Conclusions and Recommendations section of the project
Geotechnical Report or in the final report of testing and observation services perfomied
during grading.
7.5. The Consultant shall observe the placement of subdrains. to verify that the drainage devices
have been placed and constmcted in substantial confonnance with project specifications.
7.6. Testing procedures shall confomi to the following Standards as appropriate:
7.6.1. Soil and Soil-Rock Fills:
7.6.1.1. Field Density Test, ASTM D1556-82, Density of Sod In-Place By the
Sand-Cone Method.
7 6 1.2. Field Density Test, Nuclear Method, ASTM D2922-81, Density of Sod and
Soil-Aggregate In-Place by Nuclear Methods (Shallow Depth).
7 6 1 3. Laboratory Compaction Test, ASTM D1557-91, Moisture-Density
Relations of Soils and Soil-Aggregate Mixtures Using 10-Pound Hammer
and 18-Inch Drop.
7.6.1.4. Expansion Index Test, Unifomi Building Code Standard 29-2, Expansion
Index Test.
7.6.2. Rock Fills
7 6 2 1. Field Plate Bearing Test, ASTM Dl 196-64 (Reapproved 1971) Standard
Methodfor Nonrepresentative Static Plate Load Tests of Sods and Flexible
Pavement Components. For Use in Evaluation and Design of Airport and
Highway Pavements.
8. PROTECTION OF WORK
8 1 During consfruction, the Confractor shall properly grade all excavated surfaces to provid.
poshive drainage and prevent ponding of water. Drainage of surface water shall be
confrolled to avoid damage to adjoining properties or to finished work on the s.te. The
Confractor shall take remedial measures to prevent erosion of freshly graded areas until
such time as pemianent drainage and erosion confrol feamres have been installed. Areas
subjected to erosion or sedimentation shall be properly prepared in accordance with the
Specifications prior to placing additional fill or stmcmres.
8 2 After completion of grading as observed and tested by the Consultant, no ftirther
excavation or filling shall be conducted except in conjunction with the services of the
Consultant.
9. CERTIFICATIONS AND FINAL REPORTS
9 1 Upon completion of the work, Confractor shall fumish Owner a certification by the Civil
Engineer stating that the lots and/or building pads are graded to within 0.1 foot vertically of
elevations shown on the grading plan and that all tops and toes of slopes are within 0.5 foot
horizontally oftiie positions shown on the grading plans. After installation of a section of
subdrain, the project Civil Engineer should survey its location and prepare an as-built plan
oftiie subdrain location. The project Civil Engineer should verify tiie proper outlet for the
subdrains and the Confractor should ensure tiiat tiie drain system is free of obsfructions.
9.2. The Owner is responsible for fiimishing a fmal as-graded soil and geologic report
satisfactory to tiie appropriate goveming or accepting agencies. The as-graded report
should be prepared and signed by a Califomia licensed Civil Engineer expenenced m
geotechnical engineering and by a Califomia Certified Engineering Geologist, indicatmg
Lt the geotechnical aspects of the grading were perfomied in substantial conforniance
witii tiie Specifications or approved changes to tiie Specifications.
GI rcv. 8/98