HomeMy WebLinkAboutCT 81-46; Carlsbad Airport Center Unit 2; Soils Report; 1989-08-07ADDITIONAL
GEOTECHNICAL INVESTIGATION
CARLSBAD AIRPORT CENTER, UNIT 2
CARLSBAD, CALIFORNIA
PREPARED FOR
CENTER DEVELOPMENT
1921 PALOMAR OAKS WAY, SUITE 300
CARLSBAD, CALIFORNIA 92009
PREPARED BY
SAN DIEGO GEOTECHNICAL CONSULTANTS, INC.
9240 TRADE PLACE, SUITE 100
SAN DIEGO, CALIFORNIA 92126
AUGUST 7, 1989
JOB NO. 05-4879-016-00-00
LOG NO. 9-1868
-c - SAN DIEGO SOIL ENGINEERING GEOTECHNICAL a ENGINEERING CONSULTANTS, GEOLOGY INC.
- August 7, 1989
Centre Development
Carlsbad, California 92009
1921 Palomar Oaks Way, Suite 300 -
- Attention: Mr. Jerry Morrissey
Job No. 05-4879-016-00-00
Log No. 9-1868
SUEUECT : ADDITIONAL GEOTECHNICAL INVESTIGATION Carlsbad Airport Center, Unit 2,
Carlsbad, California
Gentlemen:
At your request, we have completed the Additional Geotechnical
Investigation for the proposed Carlsbad Airport Centre, Unit 2
commercial development in Carlsbad, California. This report
presents the results of our investigation, as well as our
conclusions and recommendations regarding your proposed
development.
Our estimates of removal quantities are included, as well as our
conclusion that rippability on Lot 42 will be comparable to other
areas of the project.
We recommend buttressing of three cut slopes during mass grading.
If you have any questions after reviewing our report, please do not
hesitate to contact the undersigned at your convenience. We
sincerely appreciate this opportunity to be of service.
Very truly yours,
SAN DIEGO GEOTECHNICAL CONSULTANTS, INC.
Vice President
AFB/cf
~240~R~n~~1~c.~s111~~lnn~~~~nlF~nc.~~717Fi.1fi1~15?fi.11n7.~~~~Ifil~15?Fi-l?nfi
A SUBSIDIARY OF THE IRVINE CONSULTING GROUP, INC.
.
TABLE OF CONTENTS
.
.
"
.
"
.
.
.
.
.
.
.
.
.
.
.
1.0 INTRODUCTION ...................... 1
1.1 Authorization ................... 1
1.2 Scope of Services ................. 1
2.0 SITE DESCRIPTION .................... 2
3.0 FIELD EXPLORATION ................... 3
4.0 GEOTECHNICAL SETTING AND SUBSURFACE CONDITIONS . .
4.1 Geologic Setting ..............
4.2 Geologic Units ...............
4.2.1 Santiago Peak Volcanics
4.2.2 Santiago Formation (Map Symbol Tsa)
4.2.3 Alluvium (Map Symbol Qal) .....
4.2.4 ..............
4.2.5
Topsoil
Fill ...............
4.3 Groundwater .................
......... (Map Symbol Jsp)
... 3
4
3
... 4 .. 5 ... 5 ... 6 ... 6 ... 7
... ...
5.0 QUANTITIES OF REMEDIAL EARTHWORK ............ 8
5.1 Analysis of Field Data and Method of Calculations . 8
5.2 Itemized Tally of Remedial Quantities ....... 9
5.3 Limitations .................... 9
6.0 BUTTRESS FILLS ..................... 10
7.0 RIPPABILITY OF SANTIAGO PEAK BEDROCK .......... 11
8.0 OFFSITE DAYLIGHT FILL OVER EXISTING LANDFILL ...... 11
9.0 GEOTECHNICAL EVALUATION AND RECOMMENDATIONS ...... 12
9.2 Geotechnical Observation 12
9.1 General 12
9.3 Review of Grading Plans .............. 13
10.0 LIMITATIONS OF INVESTIGATION .............. 13
...................... .............
.
. i
TABLE OF CONTENTS
(Continued)
ATTACHMENTS
Fiaures . I
Amendices
A
B
Plates
1
Location Map
References
Field Exploration Program
Geotechnical Map
ii
ADDITIONAL
GEOTECENICAL INVESTIGATION
CARLSBAD AIRPORT CENTER, UNIT 2,
CARLSBAD, CALIFORNIA
1.0 INTRODUCTION
This report presents the results of our Additional
Geotechnical Investigation ofthe proposed commercial develop-
ment in Carlsbad, California. The purpose of our work was to:
(1) Estimate quantities of alluvium, (2) Estimate quantities
of topsoil and colluvium in fill areas, (3) Analyze stability
of proposed slopes and design buttresses, as needed, (4)
Develop rock rippability recommendations. The conclusions and
recommendations in this report are based on analysis of the
data obtained from our field exploration, laboratory tests,
and experience with similar soils and geologic conditions in
this area.
1.1 Authorization
This investigation was authorized by Mr. Jerry Morrissey
of Centre Development on June 20, 1989. Our scope of
services for this investigation generally conformed to
that outlined in our Proposal No. SDP9-5277 dated June
20, 1989.
1.2 ScoDe of Services
Our Scope Of Services for this investigation included the
following:
a. Review of pertinent geotechnical literature, maps
and previous reports to outline the known Site
conditions;
Centre Development
August 7, 1989
Job No. 05-4879-016-00-00 Log No. 9-1868
Page 2
b. Subsurface investigation consisting of 17 test pits
excavated to a maximum depth of 16 feet:
c. Logging of the test pits by our field geologist to
determine depths of alluvium/colluvium:
d. Analysis of field data and estimating anticipated
removal quantities:
e. Evaluation of pertinent engineering properties of
soil units likely to affect the development:
f. Analysis of slope stability and design of slope
buttresses as needed:
g. Review of previous seismic refraction traverses for
development of rock rippability recommendations:
h. Preparation of this report with accompanying maps
and cross sections presenting our findings,
conclusions, and recommendations;
2.0 SITE DESCRIPTION
Unit 2 of the Carlsbad Airport Center will occupy a land
parcel of irregular shape located in Carlsbad, California.
The site includes about 70 acres of hills and associated small
drainage basins located east of the existing Carlsbad Airport
Center, Unit 1. The location and topography are shown on the
attached Location Map (Figure 1). The site is bounded on the
north and east by McClellan Palomar Airport, on the south by
Palomar Airport Road, and on the west by Units 1 and 3 of the
Carlsbad Airport Center.
.'I
ADAPTED FROM U.S.Q.S. 7.5' ENClNlTAS (1975)
AND SAN LUIS REY (1975) QUADRANGLES
00 NO.: DATE: - FIQURE: - " ST 1989 1
Centre Development
August 7, 1989
Job No. 05-4879-016-00-00
Log No. 9-1868 Page 3
Topographically, the site includes both low- and high-relief
areas. Total relief of the site is about 40 feet, with
elevations ranging from approximately 190 to 330 feet above
mean sea level. Three main drainages originate near the north
edge of the site and drain southwest, the largest being
adjacent to Palomar Airport Road. Natural slopes along the
eastern and western drainages reach approximately 1.5:l
(horizonta1:vertical) or steeper.
Access to the site is from improved roads in the existing
Carlsbad Airport Center, Unit 1. No structures or
improvements were noted on the site. An abandoned
agricultural reservoir presently exists near the center ofthe
site.
3.0 FIELD EXPLORATION
The field exploration performed during the course of this
investigation consisted of excavation of 17 test pits, to a
maximum depth of 16 feet. The test pits were excavated with
a Kubota KH-170L trackhoe, geologically logged and then
backfilled. This field work was supervised by our staff
geologist. Field work began on June 20, 1989 and was
completed on June 21, 1989.
4.0 GEOTECHNICAL SETTING AND SUBSURFACE CONDITIONS
4.1 Geoloaic Settinq
The site is underlain by Jurassic-age Santiago Peak
Volcanics and Eocene-age Santiago Formation sedimentary
rocks. Alluvial sediments are present in the canyon
bottoms and upland areas are covered by a thin layer of
Centre Development
August 7, 1989
Job No. 05-4879-016-00-00
Log NO. 9-1868
Page 4
topsoil and colluvium. The distribution of the geologic
units is shown on the attached Geotechnical Map (Plate
1) -
4.2 Geoloqic Units
4.2.1 Santiaqo Peak Volcanics (Maw Symbol JSD)
The Jurassic-age Santiago Peak Volcanics, a
series of mildly metamorphosed volcanic rocks,
are exposed at the western part of the site.
Regionally, the Santiago Peak Volcanics vary
in composition from basalt to rhyolite. On the
site, they are predominantly andesite. The
Santiago Peak Volcanics are moderately to
highly jointed. Joint spacings are variable:
clay fillings are usually present. The
Santiago Peak Volcanics are weathered to
varying depths and excavation will be
difficult. The highly weathered rock within
about five feet of the existing ground surface
can generally be excavated with conventional
heavy earthmoving equipment. Below that depth
heavy ripping and blasting should be expected.
Heavy ripping or blasting will generally
produce oversize materials. The difficulty of
handling and placing these materials in fills
will tend to increase the cost of grading the
site.
Centre Development August 7, 1989
Job NO. 05-4879-016-00-00
Log No. 9-1868 Page 5
4.2.2 Santiaao Formation fMaD Svmbol Tsa)
The Eocene-age Santiago Formation underlies
about three-fourths of the site. As observed,
the unit is massive to thick-bedded silty to
clayey sandstone with interbedded sandy
claystone and siltstone. Santiago Formation
rocks probably can be excavated by conventional
earth moving equipment. The claystones and
some siltstones are moderately to highly
expansive.
4.2.3 Alluvium (MaD Svmbol Oal)
Alluvium is present in the drainages. As
mapped for this project, the alluvium includes
variable deposits of colluvium at the base of
canyon side slopes. Most alluvium and
colluvium consists of dry to moist, soft, silty
and sandy clay and silty and clayey sand.
Alluvium was observed to a maximum depth of
about 14 feet and was, on the average, about
six feet deep. The alluvium appeared to be
deepest near the center of the drainage
courses, with shallower depths observed along
the margins. The colluvium was observed to a
maximum depth of about five feet and averaged
about three feet deep on canyon side slopes.
The primary concern with regard to alluvium and
colluvium is their potential for settlement in
response to loads imposed by fills or
structures. Unacceptable settlement may occur
after construction, especially if these soils
Centre Development August 7, 1989
Job No. 05-4879-016-00-00
Log No. 9-1868 Page 6
become saturated at a later date. Removal and
recompaction is recommended to mitigate this
problem. Alluvium which cannot be removed
because of a high water table may require
settlement monitoring and site specific
recommendations. Ourprevious report(Reference
1) addresses this situation in Section 7.2.3,
Site Preparation.
4.2.4 Tormoil
The topsoil seen on the site consisted of
loose, dry, fine-grained silty sand. fills or
structures should not be founded directly on
topsoil due to its limited strength and
potential for settlement and seepage. Topsoil
may be used in compacted fills if vegetation
is removed. The topsoil is not shown on the
Geotechnical Map, Plate 1.
4.2.5 Fill
Two areas of the site contain undocumented fill
and debris. In the north-central area, the
fill consists of sandy clay used to construct
an agricultural reservoir. The embankment has
been breached and the pond empty for some time.
This material may be reused as fill material
for grading if it is properly processed before
use.
North of the property line in the area of Lots
29 and 30, the fill is the result of a prior
Centre August Development
7, 1989
Job NO. 05-4879-016-00-00 Log NO. 9-1868
Page 7
landfill operation. This fill consists of
rocky soil which contains trash and debris and
is therefore not suitable for use as compacted
fill. It should be removed from the site and
properly disposed of.
Sizeable documented fills were placed on the
site along Camino Vida Robles during the
grading of Unit 1 in 1985 and 1986. These are
mostly canyon fills with maximum depths of 20
to more than 50 feet. According to the as-
graded soils report (Reference 2) these were
placed as engineered, compacted fills in
accordance with the local standards of practice
for such fills. We did not investigate or test
the fill for this report, and we relied on
Reference 2 for all information relating to the
nature and quality of the site preparation and
grading.
4.3 Groundwater
Groundwater was found in test pits 2, 3, 4, 6, 7, 8, 10
at or near the contact between alluvium and bedrock.
These are probably localized, "perchedvv water tables and
do not reflect the regional water table.
Groundwater conditions may fluctuate with seasonal
rainfall conditions, and will probably change in response
to development of the site.
Centre Development
August 7, 1989
5.0 QUANTITIES OF REMEDIAL EARTHWORK
Job No. 05-4879-016-00-00
Log No. 9-1868 Page 8
5.1 Analvsis of Field Data and Method of Calculations
Our estimates of remedial grading quantities in the
proposed fill areas for Unit 2 were based on the 80 scale
grading plan supplied by Bodas Engineering. In addition
to our field work, we have used subsurface data from our
earlier Supplemental Geotechnical Investigation
(Reference 1). Materials requiring remedial removal
consist of alluvium in canyon bottoms, colluvium and
topsoil on slopes, and undocumented fill.
Logs of the test pits excavated during our Additional
Investigation are shown in Appendix B, Figures B-1
through B-17. Remedial removal depths measured in these
test pits, plus those from our earlier Supplemental
Investigation were plotted on the Geotechnical Map. The
mapped boundary between alluvial removal areas and
colluvium and topsoil removal areas was arbitrarily
placed at the approximate contour where remedial removal
depths reach 3 feet. This contact is shown on the
Geotechnical Map. The depth of topsoil\colluvium removal
was taken to be 3 feet in all topsoil\colluvium areas.
Atypical cross section illustratingthe boundary between
an alluvium removal area, and colluvium and topsoil
removal areas is shown on Figure 2. Typical canyon
benching and cleanouts, and sidehill benching are shown
as well.
Our procedure for developing the remedial quantities
utilized a digital planimeter to measure mapped areas,
I
f
ESTIMATED CANYON DE
(ARBITRARY) BEDROCK BENCHES
CANYON BENCHES AND CLEANOUT AREA
TYPICAL CANYON CROSS-SECTION
)B NO.: - - DATE: FIQURE: -- AUGUST 1989 2
Centre Development August 7, 1989
Job NO. 05-4879-016-00-00
Log No. 9-1868 Page 9
which were multiplied by the appropriate average removal
depths. Alluvial depths were extrapolated between test
pit data.
The canyon bottom benching quantities are based on our
experience with similar grading projects utilizing large
earth moving equipment.
5.2 Itemized Tally of Remedial Ouantities
The total estimated quantities of remedial earthwork are
presented as follows:
Table I
Removal Quantities in Unit 2
Alluvium (canyons) 107,000 cubic yards
Topsoil/Colluvium
(slope and ridges in fill areas) 122,000 cubic yards
Undocumented Fill (farm ponds) 26,000 cubic yards
Landfill Benching
(north of Lots 29, 30) 5,000 cubic yards
Total 260,000 cubic yards
The quantities shown include weathered bedrock materials
expected to be removed within the mapped boundaries.
5.3 Limitations
Quantities of earth materials were derived from our field
exploration. Assumed depths were extrapolated between
test pits and borings, and were extrapolated up canyon
.-
Centre Development
August 7, 1989
Job No. 05-4879-016-00-00
Log NO. 9-1868 Page 10
sides to intercept cut/fill daylights. These quantities
are intended to be used for estimating purposes only.
Final removal depths should be determined in the field
by the geotechnical consultant during grading.
Variations in anticipated subsurface conditions as well
as methods of field measurements will affect final
earthwork quantities.
6.0 BUTTRE88 FILLS
Stability against gross sliding was analyzed using the STABL5
computer program for three proposed cut slopes in Unit 2. The
locations of the cross sections are shown on the accompanying
Plate 1. Downhole logging by our geologists located remolded
and sheared clay zones in those slopes which were included in
the computer models. The calculated factors of safety fell
below 1.5. Buttress fills were added to the cross sections
and the factors of safety rechecked to verify that they
exceeded 1.5. It was assumed that the buttresses would be
constructed of selected sandy on-site soil. Figure 3 contains
a typical buttress design.
The three buttresses are summarized below:
CROSS SECTION BUTTRESS EARTH QUANTITIES (Cubic yards)
AA 20 foot key 1,800
BB 15 foot key 1,300
cc 20 foot key 2,100
During construction, our geologist should map all back-cuts
to determine that the assumptions used in the analyses are
valid.
16' MINIMUM 7
4. DIAMETER PERFORATED
PIPE BACXDRAIN \
4. DIAMETER NON-PERFORATED
PIPE LATERAL DRAIN
SLOPE PER PLAN
BENCHING
LPROVIDE BACKDRAIN PER BACKDRAIN
DETAIL. AN ADDITIONAL BACKDRAIN
AT MID-SLOPE WILL BE REQUIRED FOR
SLOPE IN EXCESS OF 40 FEET HIGH.
TYPICAL BUTTRESS FILL DETAIL
OB NO.: FIGURE: DATE: - - " AUGUST 1989 3
Centre Development
August 7, 1989
Job No. 05-4879-016-00-00 Log NO. 9-1868 Page 11
7.0 RIPPABILITY OF SANTIAGO PEAK BEDROCK
Rippability of the Santiago Peak metavolcanic rock was
addressed in our report on Unit 2, Reference 1. However an
area of the rock located in Unit 2, Lot 42 was not tested by
us. A prior investigation by H.V. Lawmaster & Co. had run a
seismic line in Lot 42. We have reviewed the Lawmaster data
and it appears that rippability will be similar to the main
rock area in Unit 2, that is, relatively easily rippable down
to about six feet, and moderately difficult ripping below with
some blasting required due to the variable nature of the
formation.
8.0 OFFSITE DAYLIGHT FILL OVER EXISTING LANDFILL
Our field work included a test trench (T-11) in the old
landfill north of Lots 29 and 30 in Unit 2. The grading plan
calls for an offsite daylight fill to be placed over the
existing slope. We recommend that a limited removal be made
into the slope with a 1:l backcut (if possible). The fill key
subgrade should be scarified and recompacted at optimum
moisture and the new fill placed to final grade. The backcut
should encroach as far as possible into the landfill in order
to expose as much firm key area as possible. Spoils from the
landfill excavation should be removed from the site and
properly disposed of.
Centre Development
August 7, 1989
Job No. 05-4879-016-00-00 Log No. 9-1868 Page 12
9.0 GEOTECHNICAL EVALUATION AND RECOMMENDATIONS
9.1 General
In this investigation, we have addressed the following
subjects :
(1) Quantities of soil requiring removal and
recompaction consisting of alluvium in drainages,
topsoil and colluvium on slopes (in fill areas) , and
undocumented fill.
(2) Buttressing of cut slopes containing pre-sheared
clay layers.
(3) Rippability of Santiago Peak volcanic rock.
We did not identify and geotechnical conditions during
our investigation that would prevent development of Unit
2 as it is now planned, providing that the
recommendations contained in this report and our prior
report (Reference 1) are followed.
9.2 Geotechnical Observation
San Diego Geotechnical Consultants personnel should
continuously observe the grading and earthwork operations
for this project. Such observations are essential to
identify field conditions that differ from those
predicted by preliminary investigations, to adjust
designs to actual field conditions, and to determine that
the grading is in general accordance with the
recommendations of this report. Our personnel should
perform sufficient testing of fill during grading to
support the geotechnical consultant's professional
opinion as to compliance of the fill with compaction
requirements.
Centre Development
August 7, 1989
Job NO. 05-4879-016-00-00
Log NO. 9-1868 Page 13
9.3 Review of Gradina Plans
San Diego Geotechnical Consultants should review the
final grading plans for the proposed development prior
to construction. This review will allow us to assess the
compatibility of those plans with the recommendations in
this report. If the final plans differ materially from
our present understanding of the project, further
investigation and analysis or recommendations for design
changes may be necessary.
10.0 LIMITATIONS OF INVESTIGATION
our investigation was performed using the degree of care and
skill ordinarily exercised, under similar circumstances, by
reputable soils engineers and geologists practicing in this
or similar localities. No other warranty, expressed or
implied, is made as to the conclusions and professional advice
included in this report.
The samples taken and used for testing and the observations
made are believed typical of the entire project. However,
soil and geologic conditions can vary significantly between
drillholes, test pits, or other exploration locations. As in
most projects involving earthwork, the conditions revealed by
excavation during construction may vary from those predicted
in our preliminary findings. If such changed conditions are
found, they should be evaluated by the project soils engineer
and geologist. It may then be necessary to adjust the project
designs or to recommend alternate designs.
This report is issued with the understanding that the owner,
or his representative, is responsible for bringing the
information and recommendations contained herein to the
attention of the architects and engineers involved in the
Centre Development
August 7, 1989
Job No. 05-4879-016-00-00 Log NO. 9-1868 Page 14
project. The owner or his representative is also responsible
for assuring that the information and recommendations are
incorporated into the plans, and that the necessary steps are
taken to see that the contractor and subcontractors carry our
the recommendations in the field.
This firm does not practice or consult in the field of safety
engineering. we do not direct the contractor's operations,
and we cannot be responsible for anyone other than our own
personnel on the j obsite. Therefore, the safety of other
persons at the jobsite is the responsibility of the
contractor. The contractor should notify the owner promptly
if he considers any of the recommendations in the report to
be unsafe.
Our findings in this report are valid as the date of issue.
However, changes in the condition of the site can occur with
the passage of time, due either to natural processes or the
works of man on this or adjacent properties. In addition,
changes to the applicable or appropriate laws, regulations,
and standards of practice may occur as a result of either new
legislation or the broadening of knowledge. Our findings may
be invalidated wholly or in part by such changes, over which
we have no control. The validity of this report therefore
should not be relied upon after a period of three years
without a comprehensive review by San Diego Geotechnical
Consultants.
Centre Development August 7, 1989
Job No. 05-4879-016-00-00 Log NO. 9-1868
Page 15
***
-
SAN DIEGO GEOTECHNICAL CONSULTANTS, INC.
"
- Victoria Stocker WWG Rahond M. Masson Staff Geologist Project Engineer
-
W. Shaw, C.E.G. 1251
Registration Expires: 3-31-91 Registration Expires: 6-30-90
Principal Engineer Chief Geologist
APPENDIX A
References
References
1. San Diego Geotechnical Consultants, Supplemental Geotechnical
Investigation Carlsbad Airport Centre, Unit 2, and Off- Site Fill Area, Carlsbad, California, Job No. 05-4879-
011-00-00, July 29, 1988
2. H. V. Lawmaster & Company, Inc., 1980, Preliminary
Geotechnical Investigation, Proposed Palomar Business
Park, North San Diego County, California: Unpublished
Report No. 79-9394/654Gto Palomar Business Park, January
15, 1980 (includes grading plan review letters dated June
8, 1982 and September 27, 1982).
3. Moore h Taber, 1987, Report of Geotechnical Services, Carlsbad Tract No. 81-46, Airport Business Center, Unit No. 1, City of Carlsbad, California: Unpublished Report to
Centre Development Company, February 25, 1987.
4. Bonilla, M. G., 1970, Surface Faulting and Related Effects, - in Wiegel, R. L. (ea.), Eacthcruake Ensineerinq:
Englewood Cliffs, New Jersey, Prentice-Hall, p. 47-74.
5. Seed, H. B., and Idriss, I. M., 1982, Ground Motions and Soil
Research Institute, Monograph Series. Liquefaction During Earthquakes, Earthquake Engineering
6. Ploessel, M. R., and Slosson, J. E., 1974, Repeatable High Ground Accelerations From Earthquakes, California
Geology, September.
7. California Division of Mines and Geology, 1975, Recommended Guidelines for Determining the Maximum Credible and the
Maximum Probable Earthquakes: California Division of Mines and Geology Notes, Number 43.
APPENDIX B
Field Exploration
m I A
!
! TR
PROJECT NAME: Carlsbad P-irport Centre TRENCH NO.:
JOB NO.: 05-4879-016-00-00 DATE: 6-20-89
EQUIPMENT: Trackhoe 170L 24" bucket ELEVATION: 218
LOQQED BY: "' LOCATION See Map
DESCRIPTION
Topsoil/Qal: Dark brown silty CLAY, dry to moist, stiff
Santiago FM (Tsa): Weathered, brown, gray, green mottled silty clay. Moist to
wet, stiff, tan, orange iron oxide staining, mottled.
W -I n
00
Y
m
t
a
(II I N
I
JOB NO.: 05-4079-016-00-00
EQ~~~~~~~: Trackhoe 170L 24" bucket ELEVATION: 215
LOQQED BY: vs LOCATION See Map
DESCRIPTION
Alluvium (Qal): Light tan silty SAND, loose, damp.
Plluvium/Topsoil (pal): Dark brown silty CLAY, moist to wet, medium dense.
Santiago FM (Tsa): Weathered, brown gray silty SAND, moist to wet, medium dense.
Santiago FM (Tsa): Green gray mottled clayey SAND, wet, dense.
Water weeping into trench between 209' and 203'. Minor caving.
"
"
1 ENCH LOO
n Drainage
4- -
e-- -
"""
L -- 4-
4 - " c - - "
""
" -
" """--- " -
" -
I \ I I ! I I I I I I I I I
PROJECT NAME Carlsbad Airport Centre TRENCH NO.:
JOB NO.: 05-4879-016-00-00 DATE: 6-20-89
EQUIPMENT Trackhoe 170: 24" bucket ELEVATION: 214
LOGGED ey: Vs LOCATION See Map
DESCRIPTION
Alluvium (Qal): Tan SAND, dry to moist, loose.
AlluviuIn/TOpSoil (Qal): Dark brown silty, clayey SAND, moist to wet, medium dense.
Santiago FM (Tsa): Weathered, dark brown and brown clayey, silty SAND, moist to
wet, medium dense.
Water weeping into bottom of trench.
(II I P
I
J~~ 05-4879-016-00-00 DATE: 6-20-89
EQUIPMENTTrackhoP 170: 24" bucket ELEVATION: 240'
LOQQED BY: "' LOCATION See Map
DESCRIPTION
ENQINEERINQ PI
I I \ t I j ! I ! ! ! i !
PROJECT NAME: Carlsbad Airport Centre TRENCH NO.: 5
JOB NO.:
EQUIP MEN^:
LOQQED BY:
05-4879-016-00-00 DATE:
ELEVATION:
LOCATION
6-20-89
Trackhoe 170L 24” bucket 230 ‘ ”’ See Map
DESCRIPTION
Topsoil: Dark brown silty CLAY, dry to damp, medium stiff to stiff.
Santiago FM (Tsa): Tan, gray, orange mottled silty CLAYSTONE, moist, stiff to medim
stiff.
I
DROJE~T NAM~: Carlsbad Airport Centre TRENCH NO.:
108 NO.:
EQUIPMENT: Trackhoe 170: 24" bucket ELEVATION: 228'
LOQQED BY:
05-4879-016-00-00 DATE 6-20-89
"' LOCATION See Map
DESCRIPTION
Alluvium (pal): Brown, tan, gray clayey SAND, moist to wet, medium dense.
Santiago E" (Tsa): Gray, green, orange, tan mottled clayey silty SAND, wet medium
dense.
Water below 91I' caving.
BCALE 1"=10' horiz & vertical TOPOQRAPHY: TRENCH I I I I I I I
IRIEh -
I I !
m I -4
i
PROJECT ~~~~Carlsbad Airport Centre TRENCH NO.:- - NQ RING PRO
DATE:
ELEVATION: 227'
LOCATION See Map
-
NO.: 05-4879-016-00-00 6-20-89
EQUIPMENT: Trackhoe 1~70L 24" bucket
LOGQED BY: vs
DESCRIPTION
" " "
Fill (Qaf): Light tan, brown clayey SAND, dry to moist, loose to medium dense.
Topsoil: Dark brown clayey SAND, moist, medium dense.
Alluvium (Qal): Tan, brown clayey SAND, moist to wet medium dense.
Santiago FM (Tsa): Weathered, gray qreen tan mottled clayey SAND grades to green,
tan orange brown mottled sandy CLAY, moist, stiff
SCALE: 1''=10' horiz & verticalTOPOQRAPHY: - ~
TRENCH ORIENTATION N41°E - "
-
"
"
- "
" - \
"
I I I I-
"
I I I I "' I,,, It1 Ill,
"
I IIII I,,, I,, - ,*<:>< ((1,
-
Qaf - 'f~ropso,p. \ -
IIVI #I,, III
-:" -, Qal
- \ \ 3-
" "
- 1 -4
\ " .- - - ""
-\
\ -
- "
._
- " "
" - Tsa __ \
W
- - - ?" - ,- - a "" - " t
TRENCH LOG
m I aD
!
JOB NO.:
EQUIPMENT:
LOQQED BY: vs LOCATION See Map
05-4879-016-00-00 DATE
ELEVATION:
6-20-89
Trackhoe 1701. 24" bucket 222'
DESCRIPTION
Alluvium (Qal): Dark brown, SAND, wet loose grades to dark brown sandy CLAY with
gray and orange mottled stringers, wet, stiff.
Santiago FM (Tsa): Tan, orange, gray mottled silty CLAY, wet, medium dense, water
and caving.
W 2 a 2 OD
2 3
Y
m
I
m I (D
I
- E HQ Pf - -
PROJECT NAME- TRENCH NO.: 9
JOB NO.:
NQlNEERll *O
EQUIPMENT: Trackhoe 17OL 24" bucket
LOQQED BY: vs LOCATION See Map
- - -
05-4879-016-00-00 DATE
ELEVATION: 234'
6-21-89
DESCRIPTION
" " " -
Topsoil: Dark brown clayey SAND, fine grained, dry to moist, medium dense.
Alluvium (Qal): Brown Clayey SAND, fine-grained, moist, medium dense.
Santiago FM (Tsa): Tan clayey SAND, fine-grained, moist, dense, discontinuous
orange staining.
" SCALE: I"= 10' horiz & verticalTOPOQRAPHY: - - TRENCH ORIENTATION N38'~ - " "
"
-
" -
" "
"
-
" -
-
- - - -
- -
-
-
- "
"
-
" - -
" Tsa "
- -
"
.. - -
TRENCH LOO
Y
PER1 -
1 "
I I I I I I I I I 1 I I ! I I !
m I
0 4
PROJECT NAME:Carlsbad Airport Centre TRENCH NO.:
JOB NO.: 05-4879-016-00-00 DATE:
10
6-21-89
EOUIPMEN~;~~~P 170L 24" bucket ELEVATION: 242'
LOCATION: See Map
Alluvium (gal): Light tan clayey SAND, dry to moist, loose to medium dense
grading to dark gray sandy clay and clayey sand, wet, medium
dense.
Santiago FM (Tsa): Light tan and orange tan silty SAND, fine-grained, wet dense
micaceous, water and minor caving.
E
n
t
a
0
>
0
W 2
w
m I
d
d
I
PROJECT NAME: Carlsbad Airport Centre TRENCH NO.: l1
JOB NO.: 6-21-89
EQUIPMENT:
05-4879-016-00-00 DATE
Trackhoe 170L 24" bucket ELEVATION: 255' to 270'
LOGQED BY: vs LOCATION See Map
DESCRIPTION
ToJ~soil/Colluvium: Light tan silty SAND, dry to moist, loose.
Fill (Qaf): Brown clayey SAND, damp, loose to medium dense, grades to dark gray
clayey sand, moist, medium desne, fill contains riprap debris and
trash.
Santiago FM (Tsa): Green gray mottled sandy CLP-Y, moist, stiff to very stiff,
excavation caved after 90 min.
W A : < 0
Y A a m
-
TlON
'PERTIES
"
L
ENCH LOQ
I I i I i I I I I i I ! I I I 1 I I
PROJECT NAME: Carlsbad Airport Centre TRENCH NO.: l2
NO.: n~-4~79-n~~-no-nn DATE: 6-21-89
EQUIPMENT:
LOQQED BY: vs LOCATION See Map
Trackhoe 17OL 24" bucket ELEVATION: 268'
DESCRIPTION
I
Alluvium (Qal): Brown to dark brown clayey SAND, dry to damp medium dense 40%
trash and bottles. Grade to light tan, orange silty sand,
moist, medium dense.
Santiago FM (Tsa): Green brown clayey SAND, mottled discontinuous orange staining,
moist, dense, micaceous.
L
T PROJECT NAME: Carlsbad Airport Centre TRENCH NO.: 13
)OB NO.: 05-4879-016-00-00 DATE: 6-21-89
EQUIPMENT: Trackhoe 170L 24” bucket ELEVATION: 301‘
LOQQED BY: vs LOCATION See Map
DESCRIPTION
Alluvium (pal): Dark brown SAND, loose, moist, grades to dark green brown
silty clay, wet stiff to very stiff.
Santiago FM (Tsa): Orange tan SANDSTONE, moist, very dense, iron oxide staining.
I i !
ENQINEERINQ PI
-
RO
W -1 4
Y
m
a m
PROJECT NAME: Carlsbad Airport Centre TRENCH NO.: 14
J~~ 6-21-89 05-4879-016-00-00 DATE:
EQUIPMENTTrackhoe 170L 24" bucket ELEVATION: 304'
LOQQED BY: vs LOCATION See Map
DESCRIPTION
Fill (oaf): Dark brown silty CLAY, dry to moist, soft to stiff, grades to reddish
brown silty clay, moist, stiff.
Santj~ayo FM (Tsa): Orange tan weathered SANDSTONE, moist, dense.
TRENCH NO.: l5
JOB NO.: 05-4879-016-00-00 DATE: 6-21-89
EQUIPMENT: Trackhoe 170L 24" bucket ELEVATION: 293'
LOQQED BY: 'JS LOCATION See Map
DESCRIPTION
Alluvium (Qal): Dark brown silty CLAY, dry to moist, stiff.
Santiago FM (Tsa): Tan orange silty CLAYSTONE, moist, stiff, gypsum stringers
angular andesitic rocks measuring from 2" to 12".
and red iron oxide staining. Rare quartzite cobbles and
I 1 I I I I I
T
Tsa
I I I I I I ! t I I I
PIKMCT Carlsbad Airport Centre TRENCH NO.: l6
05-4879-016-00-00 DATE 6-22-89
EQUIWENT:
LWD BY:
Trackhoe 170L 24" bucket ELEVATION:
LOCATION "' See Map
DESCRIPTION
Alluvium (Qal): Brown silty matrix with angular andesitic rocks ranging in size
from pebbles to 2' boulders, dry, loose.
Santiago Peak FM (Jsp): Orange tan silty matrix in joints and seams around
angular andesitic rocks matrix is damp and dense.
! I I I 1 ! I I I I I 1. ! I
[II I
PROJECT NAME: Carlsbad Airport Centre TRENCH NO.: 17
JOB NO.:
EQUIPMENT: Trackhoe 170L 24" bucket
LOGGED BY: "' LOCATION See Map
05-4879-016-00-00 DATE: 6-22-89
ELEVATION: 232'
DESCRIPTION
Alluvium (Qaf): Light tan silty matrix, dry and loose, surrounding angular
andesitic rocks ranging in size from pebbles to boulders
(4' on a side) and minor amounts of trash.
Santiago Peak FM (Jsp): Dark brown silty matrix 60% angular andesitic rock.
Matrix is moist and dense.
"I-+
'RENCH LOQ
j I I I
INEE -
Y 2 a m
PER1 -
0
Y *
Y a a c : s
I I I I I I I I I I I I I ! I