HomeMy WebLinkAboutCT 13-03; ROBERTSON RANCH WEST VILLAGE; AS GRADED REPORTS OF ROUGH GRADING; 2016-02-03LGC Valley, Inc.
Geotechnical Consulting,
AS-GRADED REPORT OF ROUGH-GRADING,
LOTS 59, 60, 216-225, 234-244, 299-301,
308-310, AND 320-324,
PLANNING AREAS PA-5, PA-6, AND PA-9&10,
ROBERTSON RANCH,
CARLSBAD TRACT NO.13-03,
CARLSBAD, CALIFORNIA
Project No. 133023-03
Dated: February 3, 2016
Prepared For:
Toll Brothers
725 Town and Country Road, Suite 200
Orange, California 92868
2420 Grand Avenue, Suite F2 • Vista • CA 92081 (760) 599-7000 • Fax (760) 599-7007
LGC Valley, Inc.
Geotechnical Consulting
February 3, 2016
Mr. Greg Deacon
Toll Brothers
725 Town and Country Road, Suite 500
Orange, California 92868
Project No. 133023-03
Subject: As-Graded Report of Rough Grading, Lots 59, 60, 216 through 225, 234 through 244, 299
through 301, 308 through 310, and 320 through 324, Planning Areas PA-5, PA-6, and PA-
9&10, Robertson Ranch, Carlsbad Tract No. 13-03, Carlsbad, California
In accordance with the request and authorization of Toll Brothers, LGC Valley, Inc. (LGC) has provided
geotechnical services during the rough-grading operations for Lots 59 and 60 of Planning Area PA-5; Lots 216
through 225 and 234 through 244 of Planning Area PA-6; and Lots 299 through 301, 308 through 310, and 320
through 324 of Planning Areas PA-9 and PA-10; part of the Robertson Ranch project (Carlsbad Tract No. 13-
03) located within the City of Carlsbad, California. The accompanying as-graded report of rough-grading
summarizes our observations, field and laboratory test results, and the geotechnical conditions encountered
during grading of the subject lots.
The rough-grading operations for the subject lots were performed in general accordance with previously
published project geotechnical reports (Appendix A), geotechnical recommendations made during the course of
grading, and the City of Carlsbad grading requirements. It is our professional opinion that the subject lots are
suitable for the intended use provided the recommendations included herein and in the project geotechnical
reports are incorporated into the fine-grading, design, and construction of the proposed development and
associated improvements. As of the date of this report, the rough-grading operations for the subject lots are
essentially complete.
If you have any questions regarding our report, please contact this office. We appreciate this opportunity to be
of service.
Respectfully Submitted,
LGC Valley, Inc.
0 wva~,
Randall Wagner, CEG 1612
Senior Project Geologist
I1IaiThiI
114 - Basil Hattar, GE 2734
Principal Engineer
Distribution: (7) Addressee
(1) Toll Brothers; Attention Ms. JoAnn Epstine (via e-mail)
(1) Toll Brothers; Attention Mr. Kevin Brickley (via e-mail)
(1) Toll Brothers; Attention Mr. Mike Steffen (via e-mail)
2420 Grand Avenue, Suite F2 • Vista • CA 92081 (760) 599-7000 • Fax (760) 599-7007
TABLE OF CONTENTS
Section
1.0 INTRODUCTION ......................................................................................................................................... 1
2.0 SUMMARY OFROUGH-GRADING OPERATIONS.................................................................................2
2.1 As-Graded Conditions ....................................................................................................................... 2
2.2 Site Preparation and Removals.........................................................................................................3
2.3 Stability Fills.....................................................................................................................................4
2.4 Subdrain Installation.........................................................................................................................4
2.5 Overexcavation of Cut/Fill Transition Conditions ............................................................................4
2.6 Overexcavation of Cut Lots...............................................................................................................5
2.7 Fill Placement and Compaction ........................................................................................................ 5
2.8 Laboratory Testing............................................................................................................................5
2.9 Field Density Testing ........................................................................................................................ 5
2.10 Graded Slopes ................................................................................................................................... 6
3.0 CONCLUSIONS...........................................................................................................................................7
3.1 General .............................................................................................................................................. 7
3.2 Summary of Conclusions..................................................................................................................7
4.0 RECOMMENDATIONS ............................................................................................................................... 9
4.1 Earthwork.........................................................................................................................................9
4.2 Site Preparation...............................................................................................................................9
4.3 Excavations ......................................................................................................................................9
4.4 Fill Placement and Compaction.....................................................................................................10
4.5 Preliminary Foundation Recommendations ..................................................................................10
4.6 Control of Surface Water and Drainage ........................................................................................ 11
5.0 LIMITATIONS ........................................................................................................................................... 12
Appendices
Appendix A - References
Appendix B - Laboratory Testing Procedures and Test Results
Project No. 133023-03 Page i February 3, 2016
1.0 INTRODUCTION
In accordance with the request and authorization of Toll Brothers, LGC Valley, Inc. (LGC) has provided
geotechnical services during the rough-grading operations of Lots 59 and 60 of Planning Area PA-5; Lots 216
through 225 and 234 through 244 of Planning Area PA-6; and Lots 299 through 301, 308 through 310, and
320 through 324 of Planning Areas PA-9 and PA-10; part of the Robertson Ranch project (Carlsbad Tract No.
13-03) located within the City of Carlsbad, California. This as-graded report summarizes our observations,
field and laboratory test results, and the geotechnical conditions encountered during grading of the subject
lots. The subject rough-grading operations were performed in general accordance with previously
published project geotechnical reports (Appendix A), geotechnical recommendations made during the
course of grading, and the City of Carlsbad grading requirements. As of this date, the rough-grading
operations for the subject lots are essentially complete.
The Rough Grading Plans for the Robertson Ranch project, prepared by O'Day Consultants (O'Day, 2014b),
were utilized as a base map to present the as-graded geotechnical conditions and approximate locations of the
field density tests. The As-graded Geotechnical Map and the Field Density Test Location Map will be
provided in the final as-graded report for Robertson Ranch upon completion of all of the rough-grading
operations.
Lots 59 and 60 of Planning Area PA-5 are located in the western portion of Robertson Ranch along the south
side of Glasgow Drive while Lots 216 through 225 and 234 through 244 of Planning Area PA-6 and Lots 299
through 301, 308 through 310, and 320 through 324 of Planning Areas PA-9 and PA-10 are located in the
east-central portion of the project along Wadsworth Street, Chase Court and Kentner Court. Ultimately,
development of Planning Area PA-5, PA-6, and PA-9 and 10 will include the construction of 36, 87, and
75 single-family residential lots, respectfully; along with associated retaining walls, slopes, storm water
retention basins, and adjacent streets. The rough-grading operations for Lots 59 and 60 of Planning Area
PA-5; Lots 216 through 225 and 234 through 244 of Planning Area PA-6; and Lots 299 through 301, 308
through 310, and 320 through 324 of Planning Areas PA-9 and PA-10 were performed as a part of grading
operations for the entire Robertson Ranch Development between September 2014 and October 2015.
Project No. 133023-03 Page 1 February 3, 2016
2.0 SUMMARY OF ROUGH-GRADING OPERATIONS
Rough-grading of the subject site began on September 5, 2014 and was essentially completed as of October
22, 2015. The grading operations were performed under the observation and testing services of LGC Valley,
Inc. Our field technicians were onsite on a full-time basis during the grading operations while our field
geologist was onsite on a periodic basis. The rough-grading operations included:
Removal and off-site disposal of vegetation and miscellaneous debris;
The removal of potentially compressible soils including colluvium, topsoil, undocumented fill, and
weathered soils to competent formational material;
Overexcavation of cut/fill transition conditions within the lots;
Overexcavation of buried cut/fill transition conditions such that the resulting fill differential beneath
the proposed building pads was less than a 3:1 (maximum fill thickness to the minimum fill
thickness);
Overexcavation of cut lots due to expansive soils;
Preparation of areas to receive fill;
The placement of subdrains in the canyon bottoms and along the heel of the stability fill keys;
Excavation of formational material; and
The placement of compacted fill soils creating the graded pads and adjacent slopes.
The rough-grading operations consisted of the placement of fill up to approximately 45 feet in depth and
cuts up to approximately 20 feet within the subject lots. During the rough-grading operations, remedial
grading was also performed so that the fill differentials beneath the proposed building pads were less than a
3:1 (maximum fill thickness to the minimum fill thickness).
2.1 As-Graded Conditions
The as-graded conditions encountered during grading of the lots were essentially as anticipated. In the
vicinity of the Lots 234 through 244, 299, 308, 309, 323, and 324, minor alluvium and colluvium
were encountered on the upper hillsides and small tributary ravines of the main canyon running in a
northwest-southeast between Planning Areas PA-6 and PA-9/PA-10 and in the small canyon in the
vicinity of Lots 323 and 324. Formational material was encountered on the slopes and at design cut
grade below a thin veneer of topsoil and weathered soils on the remainder of the lots.
All unsuitable and potentially compressible soils were removed prior to fill placement. This included
alluvium, colluvium, undocumented fill (associated with the past agricultural operations), and
weathered formational materials. The alluvium, colluvium, and topsoil typically consisted of light
brown to brown silty fine sands, sandy clays and clayey sands derived from on-site soils and were
found to be very low to highly expansive, porous, and contained scattered organics. Removals of
alluvium and colluvium up to approximately 5 to 15 feet in depth were made in the vicinity of Lots
234 through 244, 299, 308, 309, 323, and 324. Removals of the topsoil and weathered formational
material that was on the order of 2 to 6 feet were made in the other areas of the site.
Project No. 133023-03 Page 2 February 3, 2016
The formational material encountered on the subject lots consisted of the Santiago Formation. The
material was found to be massively bedded to cross-bedded silty sandstones and minor clayey
sandstones, silty claystones and sandy siltstones. The claystones and siltstones generally were olive
green and orange brown, damp to moist, stiff to hard, moderately fractured and sheared. The
sandstone generally consisted of light olive green, light brown and pale orange brown (where iron-
oxidized stained), damp to moist, dense to very dense, silty very fine to medium grained sandstone.
The majority of the Santiago material encountered within Robertson Ranch consisted of silty fine
sands. Bedding within the Santiago Formation was highly variable, but overall, generally dipped 2
to 15 degrees to the west-southwest.
A zone of two to three minor inactive faults was geologically mapped trending in a north-south
direction in the middle of Planning Areas PA-9 and PA-b. Geologic mapping indicated the faults
trended NYE to N16°E steeply dipping 60 to 85 degrees to the west. The faults were only observed
within the Santiago Formation and the fault zone appeared to die out to the south. Based on our
geologic analysis during the current grading operations and review of the applicable geotechnical
reports referenced in Appendix A, it is our professional opinion that the faults are not active; and
therefore are not a constraint to development.
No groundwater was encountered during the grading of the subject lots. However, unanticipated
seepage conditions may occur after the completion of grading and establishment of site irrigation
and landscaping. If these conditions should occur, steps to mitigate the seepage should be made on
a case-by-case basis.
2.2 Site Preparation and Removals
Prior to grading, the site was cleared of light vegetation and other miscellaneous debris and the
material was disposed of at an offsite facility. Undocumented fill, topsoil, alluvium, colluvium, and
weathered formational material were removed down to competent material (i.e. dense unweathered
formational material). Remedial removals on site, below the existing ground surface, ranged from
approximately 2 to 20 feet in depth. The thickness of compacted fills placed during this recent rough-
grading operation, to achieve design rough grades (or sheet-graded pad elevations), ranged from 0 to
approximately 45 feet.
Following the remedial removals or overexcavations, areas to receive fill were scarified
approximately 6-inches, moisture-conditioned, as needed, to obtain a near-optimum moisture content
and compacted to a minimum 90 percent relative compaction (for fills of approximately 40 feet or
less from design grades) or 93 percent relative compaction (for engineered fill below approximately
40 feet from design finish grades), as determined by ASTM Test Method D6938 (i.e. the nuclear
gauge method).
Project No. 133023-03 Page 3 February 3, 2016
2.3 Stability Fills
Stability fills were constructed to stabilize the exposed blocky claystone/siltstone and/or adverse (i.e.
out-of-slope) geologic conditions present within the Santiago Formation. The stability fill keys were
excavated to a width of approximately 15 feet and a minimum depth of 3 to 5 feet below the toe-of-
slope. The keyway bottom was angled at least 2 percent into-the-slope.
The stability fill front cuts were excavated near vertical while the back-cuts were excavated at an
approximate 1:1 to 1.5 (horizontal to vertical) slope inclinations. Stability fills were excavated along
the proposed slopes on: 1) the southwest side Lot 60; 2) the southeast side of Lots 59 and 60; 3) the
west side of Lots 216 through 225; 4) the north side of Lots 299 through 301; and 5) the north side of
Lots 320 through 323.
2.4 Subdrain Installation
Canyon and stability fill subdrains were installed under the observation of a representative of LGC in
general accordance with the planned locations of the approved geotechnical report, and the standard
details (LGC, 2014a). After the potentially compressible material in the canyons were removed to
competent material or when compacted fill was placed over competent material to obtain flow to a
suitable outlet location, a subdrain was installed along the canyon bottom.
The canyon subdrains consisted of a 6-inch diameter perforated pipe surrounded by a minimum of 9-
cubic feet (per linear foot) of crushed 3/4-inch gravel wrapped in Mirafi 140N filter fabric. In addition
to the canyon subdrains, subdrains were also installed along the bottom backside of the stability fill
keys. The stability fill subdrains consisted of a 4-inch diameter perforated pipe surrounded by a
minimum of 3-cubic feet (per linear foot) of clean 3/4-inch gravel wrapped in Mirafi 140N filter
fabric.
The canyon and stability fill subdrains were placed with a minimum 1-percent fall (2-percent or
greater where possible) to a suitable outlet location. The location of the subdrains placed during the
mass grading operations for the project were surveyed by the project civil engineer.
2.5 Overexcavation of Cut/Fill Transition Conditions
Based on the as-graded conditions, the cut/fill transition condition present within the lots, as shown on
the rough grading plans (O'Day, 2014b), were overexcavated a minimum of 5 feet in depth beneath
the proposed finish grade surface of the lot. The overexcavation extended to a distance of at least 10
feet outside the planned building limits. Lots that were overexcavated due to the cut/fill transition
condition include Lots 244, 300, 301, 310, 322, and 323. During the rough-grading operations,
remedial grading was also performed so that the fill differential beneath the proposed building pads
was less than a 3:1 (maximum fill thickness to the minimum fill thickness).
Project No. 133023-03 Page 4 February 3, 2016
2.6 Overexcavaiion of Cut Lois
During the rough-grading operations, the overexcavation of cut lots was performed in order to
mitigate potential adverse conditions due to expansive soils. The entire portion of the cut lots were
overexcavated a minimum of 5 feet below finish pad grade and replaced with compacted fill having a
lower expansion potential. In order to minimize potential ponded ground water conditions on the
overexcavation bottom, the bottom was sloped toward the street with a minimum fall of one percent.
Cut lots that were overexcavated included Lots 60, 320, and 321.
2.7 Fill Placement and Compaction
After processing the areas to receive fill, native soil was generally spread in approximately 8-inch
loose lifts, moisture-conditioned as needed to attain near-optimum moisture content, and compacted
to at least 90 or 93 percent of the maximum dry density determined in accordance with ASTM Test
Method D1557. Fill soils less than 40 feet below the design finish grades were compacted to a
minimum 90 percent relative compaction while fill soils greater than 40 feet below the design finish
grades were compacted to a minimum 93 percent relative compaction. Compaction was achieved by
use of heavy-duty construction equipment. Areas of fill in which either field density tests indicated
less than 90 or 93 percent relative compaction or the soils exhibited nonuniformity and/or showed an
inadequate or excessive moisture content, were reworked, recompacted, and retested until a minimum
90 or 93 percent relative compaction and near-optimum moisture content was achieved.
2.8 Laboratory Testing
Maximum dry density tests of representative on-site soils were performed (by others during the
previous investigation and by LGC during the current rough-grading operations) in general
accordance with ASTM Test Method D1557. Expansion potential, soluble sulfate content, and
corrosion testing of representative fmish grade soils within the subject lots were performed. Based on
the laboratory .testing, Lots 59 and 234 through 244 have a very low expansion potential; Lots 216
through 225 have a low expansion potential; and Lots 60, 299 through 301, 308 through 310, and 320
through 324 have a medium expansion potential. Laboratory testing also indicated that the near
surface soils have a negligible soluble sulfate content; are corrosive to severely corrosive to buried
metals based on the minimum soil resistivity values; and are corrosive to buried metals and
reinforcing steel in concrete based on the chloride concentrations. The laboratory test results are
presented in Appendix B.
2.9 Field Density Testing
Field density testing was performed using the Nuclear-Gauge Method (ASTM Test Method
D6938). The approximate test locations and the results of the field density tests will be provided in
the final as-graded report for Robertson Ranch upon completion of the rough grading operations.
The field density testing was performed in general accordance with the applicable ASTM standards
Project No. 133023-03 Page 5 February 3, 2016
and the current standard of care in the industry. In-situ soil density testing is intended to verify the
effectiveness of the earthmoving operation in general and is performed on a spot-check basis; as
such, some variations in relative compaction should be expected from the results documented
herein.
2.10 Graded Slopes
Manufactured fill slopes within the subject lots were surveyed by the civil engineer and constructed
with slope inclinations of 2:1 (horizontal to vertical) or flatter. Permanent graded fill slopes adjacent
to or within the subject areas range from approximately 5 to 50 feet in height. There are no
permanently graded cut slopes within or adjacent to the subject areas. The on-site fill slopes are
considered grossly and surficially stable from a geotechnical standpoint (under normal
irrigation/precipitation patterns) provided the project geotechnical recommendations are
incorporated into the fine-grading, post-grading, construction, and post-construction phases of site
development.
Project No. 133023-03 Page 6 February 3, 2016
3.0 CONCLUSIONS
3.1 General
The rough-grading of Lots 59 and 60 of Planning Area PA-5; Lots 216 through 225 and 234 through
244 of Planning Area PA-6; and Lots 299 through 301, 308 through 310, and 320 through 324 of
Planning Areas PA-9 and PA-10 of the Robertson Ranch development located within the City of
Carlsbad, California was performed in general accordance with the project geotechnical report
(LGC, 2014a), geotechnical recommendations made during the course of grading, and the City of
Carlsbad grading requirements. It is our professional opinion that the subject lots are suitable for
the intended use provided the recommendations of the referenced geotechnical reports (LGC,
2014a and 2015a through 2016b) are incorporated into the design and construction; and that proper
landscaping, irrigation, and maintenance programs are implemented.
3.2 Summary of Conclusions
The following is a summary of our conclusions concerning the rough-grading of Lots 127 through
149 of Planning Area PA-3:
Rough-grading of the lots is essentially complete.
Geotechnical conditions encountered during the rough-grading operation were generally as
anticipated.
The geologic units encountered during the rough-grading of the site consisted of undocumented
fill soils, topsoil, colluvium, alluvium, and the Santiago Formation.
Unsuitable undocumented fill soils, topsoil, colluvium, alluvium, and desiccated and/or weathered
formational material were removed to competent formational material within the limits of
grading.
Landslides or surficial slope failures were not encountered during the grading operations.
No evidence of active faulting was encountered during the rough-grading operations; however,
a zone of two to three minor inactive faults was encountered trending in north-south direction
in the middle of Planning Areas PA-9 and PA-10 (i.e. in the vicinity of Lots 310 and 320).
Based on our geologic analysis, it is our professional opinion that the faults are not active; and
therefore are not a constraint to development.
Ground water seepage conditions were not encountered during the subject grading operations.
Stability fills were constructed to improve the gross stability of the cut slope exposing fractured
and blocky formational material and/or adverse geologic conditions on the site and were
excavated in accordance with the project geotechnical recommendations. Stability fills were
excavated along the proposed slopes on: 1) the southwest side Lot 60; 2) the southeast side of
Lots 59 and 60; 3) the west side of Lots 216 through 225; 4) the north side of Lots 299 through
301; and 5) the north side of Lots 320 through 323.
Project No. 133023-03 Page 7 February 3, 2016
Subdrains were placed in the canyon bottom and along the heel of the stability fill keys. The
subdrains were (or will be) outletted into suitable storm drain facilities or near the toe-of-slope
of the stability fill slopes.
The cut/fill transition conditions present within the limits of Lots 244, 300, 301, 310, 322, and 323
were overexcavated a minimum of 5 feet beneath the finish grade surface and to a distance of at
least 10 feet outside the planned building limits.
Overexcavation of Lots 60, 320, and 321 was performed in order to mitigate potential adverse
conditions due to expansive soils. The entire portion of the cut lots were overexcavated a
minimum of 5 feet below finish pad grade and replaced with compacted fill having a lower
expansion potential.
During the rough-grading operations, remedial grading was performed so that the fill differential
beneath the proposed building pads was less than a 3:1 (maximum fill thickness to the minimum
fill thickness).
Fill soils were derived from on-site soils. 'Where tested, the fill soils within the site were
compacted at least a 90 or 93 percent relative compaction (based on ASTM Test Method
D1557) and near-optimum moisture content in accordance with the recommendations of the
project geotechnical report (LGC, 2014a) and the requirements of the City of Carlsbad. Fill
soils less than 40 feet below the design finish grades were compacted to a minimum 90 percent
relative compaction while fill soils greater than 40 feet below the design finish grades were
compacted to a minimum 93 percent relative compaction.
Due to the dense nature of the on-site soils, it is our professional opinion that the liquefaction
hazard at the site is considered low.
Representative testing of the finish grade soils on the building pads of the subject lots indicated
that the near-surface soils on Lots 59 and 234 through 244 have a very low expansion potential;
Lots 216 through 225 have a low expansion potential; and Lots 60, 299 through 301, 308 through
310, and 320 through 324 have a medium expansion potential. The test results are presented in
Appendix B.
The potential for soluble sulfate attack on concrete in contact with the finish grade soils of the
subject lots is considered negligible based on ACI Criteria (ACT 318R-05 Table 4.3.1). The
soluble sulfate content test results are included in Appendix B.
Laboratory testing of representative soil samples indicated that the near surface soils are corrosive
to severely corrosive to buried metals. The laboratory test results are presented in Appendix B.
It is our professional opinion that the slopes of the development are considered to be grossly
and surficially stable, as constructed, under normal irrigation/precipitation patterns, provided
the recommendations in the project geotechnical reports are incorporated into the post-grading,
construction and post-construction phases of site development.
Project No. 133023-03 Page 8 February 3, 2016
4.0 RECOMMENDATIONS
4.1 Earthwork
We anticipate that future earthwork at the site will consist of site preparation, fine-grading, utility
trench excavation and backfill, retaining wall backfill, and street/driveway and parking area
pavement section preparation and compaction. We recommend that the earthwork on site be
performed in accordance with the geotechnical recommendations presented in the project
preliminary geotechnical report (LGC, 2014a) and the City of Carlsbad grading requirements.
4.2 Site Preparation
During future grading (if any), the areas to receive structural fill or engineered structures should be
cleared of surface obstructions, potentially compressible material (such as desiccated fill soils or
weathered formational material), and stripped of vegetation. Vegetation and debris should be
removed and properly disposed of off-site. Holes resulting from removal of buried obstructions that
extend below finish site grades should be replaced with suitable compacted fill material. Areas to
receive fill and/or other surface improvements should be scarified to a minimum depth of 12
inches, brought to optimum moisture condition, and recompacted to at least 90 percent relative
compaction (based on ASTM Test Method D1557).
If the length of time between the completion ofgrading and the construction of the development is
longer than six months, we recommend that the building pads be evaluated by the geotechnical
consultant and, if needed, the finish grade soils on the building pads should be scarified a minimum
of 12 inches, moisture-conditioned to optimum moisture-content and recompacted to a minimum
90 percent relative compaction (based on ASTM Test Method D1557).
4.3 Excavations
Excavations of the on-site materials may generally be accomplished with conventional heavy-duty
earthwork equipment. It is not anticipated that blasting will be required or that significant quantities of
oversized rock (i.e. rock with maximum dimensions greater than 8 inches) will be generated during
future grading. However, localized cemented zones within the cut areas may be encountered on the
Site that may require heavy ripping and/or removal. If oversized rock is encountered, it should be
placed in accordance with the project geotechnical recommendations (LGC, 2014a), hauled offsite, or
placed in non-structural or landscape areas.
Temporary excavations maybe cut vertically up to five feet. Excavations over five feet should be slot-
cut, shored, or cut to a 1:1 (horizontal to vertical) slope gradient. Surface water should be diverted
away from the exposed cut, and not be allowed to pond on top of the excavations. Temporary cuts
should not be left open for an extended period of time. Planned temporary conditions should be
reviewed by the geotechnical consultant in order to reduce the potential for sidewall failure. The
geotechnical consultant may provide recommendations for controlling the length of sidewall exposed.
Project No. 133023-03 Page 9 February 3, 2016
4.4 Fill Placement and Compaction
The on-site soils are generally suitable for use as compacted flu I provided they are free or organic
material, debris, and rock fragments larger than 8 inches in maximum dimension. We do not
recommend that high or very high expansive soils be utilized as fill for the building pads or as
retaining wall backfill.
All fill soils should be brought to 2-percent over the optimum moisture content and compacted in
uniform lifts to at least 90 percent relative compaction based on the laboratory maximum dry density
(ASTM Test Method Dl 557). The optimum lift thickness required to produce a uniformly compacted
fill will depend on the type and size of compaction equipment used. In general, fill should be placed
in lifts not exceeding 8 inches in compacted thickness. Placement and compaction of fill should be
performed in general accordance with current City of Carlsbad grading ordinances, sound
construction practices, and the project geotechnical recommendations.
If import soils are to be used as fill, they should be: 1) essentially free from organic matter and other
deleterious substances; 2) contain no materials over 6 inches in maximum dimension; 3) have a very
low to low expansion potential (i.e. an Expansion Index ranging from 0 to 50); and 4) have a
negligible sulfate content. Representative samples of the desired import source should be given to the
Geotechnical Consultant at least 48 hours (2 working days) before importing grading begins so that its
suitability can be determined and appropriate tests performed.
4.5 Foundation Recommendations
The preliminary foundation design recommendations applicable to the construction of the residential
structures on the subject lots were previously provided in the our letter report entitled "Preliminary
Foundation Design for the Single-Family Residential Structures, Planning Areas PA-3, PA-5, PA-6,
PA-9, PA-b, and PA-13, Robertson Ranch", dated April 14, 2015 (LGC, 2015a) and our letter
entitled "Deepened Footing Recommendation of Building Foundation Adjacent to Proposed Nexus
eWater Recycler System, Planning Areas PA-3, PA-5, PA-6, PA-9, PA-b, and PA-13, Robertson
Ranch" dated July 23, 2015 (LGC, 2015c). The previous recommendations remain applicable for the
design of the proposed structures on the subject lots.
Based on the expansion potential and corrosion laboratory testing of representative soils on the
subject lots, Lots 59 and 234 through 244 have a very low expansion potential; Lots 216 through 225
have a low expansion potential; and Lots 60, 299 through 301, 308 through 310, and 320 through 324
have a medium expansion potential. The finish grade soils on these lots are considered to have
negligible sulfate content and are corrosive to severely corrosive to buried metals. The results of the
expansion potential and corrosion testing are presented in Appendix B.
Project No. 133023-03 Page 10 February 3, 2016
4.6 Control of Surface Water and Drainage
Surface drainage should be carefully taken into consideration during fme-grading, landscaping, and
building construction. Positive drainage of surface water away from structures is very important. No
water should be allowed to pond adjacent to buildings or the top of slopes. Positive drainage may be
accomplished by providing drainage away from buildings at a gradient of at least 2 percent for a
distance of at least 5 feet, and further maintained by a swale of drainage path at a gradient of at least 1
percent. Where limited by 5-foot side yards, drainage should be directed away from foundations for a
minimum of 3 feet and into a collective swale or pipe system. Where necessary, drainage paths may
be shortened by use of area drains and collector pipes. Eave gutters also help reduce water infiltration
into the subgrade soils if the downspouts are properly connected to appropriate outlets.
The impact of heavy irrigation or inadequate runoff gradient can create perched water conditions,
resulting in seepage or shallow groundwater conditions where previously none existed. Maintaining
adequate surface drainage and controlled irrigation will significantly reduce the potential for
nuisance-type moisture problems. To reduce differential earth movements (such as heaving and
shrinkage due to the change in moisture content of foundation soils, which may cause distress to a
structure or improvement), the moisture content of the soils surrounding the structure should be kept
as relatively constant as possible.
All area drain inlets should be maintained and kept clear of debris in order to function properly.
Rerouting of site drainage patterns and/or installation of area drains should be performed, if necessary.
A qualified civil engineer or a landscape architect should be consulted prior to rerouting of drainage.
Project No. 133023-03 Page 11 February 3, 2016
5.0 LIMITATIONS
Our services were performed using the degree of care and skill ordinarily exercised, under similar
circumstances, by reputable 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 submitted for laboratory testing, the observations made and the in-situ field testing
performed are believed representative of the entire project; however, soil and geologic conditions revealed by
excavation may be different than our preliminary findings. If this occurs, the changed conditions must be
evaluated by the project soils engineer and geologist and design(s) adjusted as required or alternate design(s)
recommended.
This report is issued with the understanding that it is the responsibility of the owner, or of his/her
representative, to ensure that the information and recommendations contained herein are brought to the
attention of the architect and/or project engineer and incorporated into the plans, and the necessary steps
are taken to see that the contractor and/or subcontractor properly implements the recommendations in the
field. The contractor and/or subcontractor should notify the owner if they consider any of the
recommendations presented herein to be unsafe.
The findings of this report are valid as of the present date. However, changes in the conditions of a
property can and do occur with the passage of time, whether they be due to natural processes or the works
of man on this or adjacent properties.
In addition, changes in applicable or appropriate standards may occur, whether they result from legislation
or the broadening of knowledge. Accordingly, the findings of this report may be invalidated wholly or
partially by changes outside our control.
Project No. 133023-03 Page 12 February 3, 2016
APPENDJX A
References
American Society of Civil Engineers (ASCE), 2013, Minimum design loads for buildings and other
structures, ASCE/SEI 7-10, Third Printing, 2013.
California Building Standards Commission (CBSC), 2013a, California Building Code, California
Code of Regulations, Title 24, Part 2, Volume 1 and 2 of 2 (based on the 2012 International
Building Code).
CBSC, 2013b, California Residential Building Code, California Code of Regulations, Title 24, Part
2.5,(based on the 2012 International Residential Code).
CBSC, 2013c, California Green Building Standards Code, California Code of Regulations, Title 24,
Part 11.
GeoSoils, Inc., 2002, Geotechnical evaluation of the Robertson Ranch Property, City of Carlsbad,
San Diego County, California, W.O. 3098-Al-SC, dated January 29, 2002.
GeoSoils, Inc., 2004, Updated geotechnical evaluation of the Robertson Ranch property, Carlsbad,
San Diego County, California, W.O. 3098-A2-SC, dated September 20, 2004.
GeoSoils, Inc., 2010, Updated geotechnical investigation for Robertson Ranch West Village,
Carlsbad, San Diego County, California, W.O. 6145-A-SC, dated October 10, 2010.
GeoSoils, Inc., 2011, Supplement to the updated geotechnical investigation for Rancho Costera
(formerly Robertson Ranch West Village), Carlsbad, San Diego County, California, W.O.
6145-Al-SC, dated June 6.
GeoSoils, Inc., 2012, Preliminary geotechnical review of "vesting master tentative map for Rancho
Costera," 40-scale plans, sheets 1 through 21, Job No. 101307, Revised May 1, 2012, by
O'Day Consultants, W.O. 6145-A9-SC, dated May 24, 2012.
GeoSoils, Inc., 2013, Addendum to the updated and supplemental geotechnical investigations for
Rancho Costera (formerly Robertson Ranch West Village), Carlsbad, San Diego County,
California, W.O. 6145-A10-SC, dated July 16, 2013.
LGC Valley, Inc., 2014a, Geotechnical and environmental recommendations for Robertson Ranch
West, Carlsbad Tract No. 13-03, Carlsbad, California, Project Number 133023-03, dated
April 29, 2014.
LGC Valley, Inc., 2014b, Change of geotechnical consultant, Robertson Ranch West Project,
Carlsbad Tract No. 13-0, Carlsbad, California, Project No. 133023-03, dated May 6, 2014.
LGC Valley, Inc., 2015a, Preliminary foundation design for the single-family. residential structures,
Planning Areas PA-3, PA-5, PA-6, PA-9, PA-b, and PA-13, Robertson Ranch, Carlsbad
Tract No. 13-03, Carlsbad, California, Project No. 1.33023-06, dated April 14, 2015.
Project No. 133023-03 Page ,4-1 February 3, 2016
References (continued)
LGC Valley, Inc., 2015b, Preliminary Review of Building Setbacks for the Proposed Residential
Planning Areas 3, 5, 6, 9, 10, and 13, Robertson Ranch, Carlsbad Tract No. 13-03, Carlsbad,
California, Project No. 133023-03, dated February 27, 2015, revised June 24, 2015.
LGC Valley, Inc., 2015c, Deepened Footing Recommendation of Building Foundation Adjacent to
Proposed Nexus ëWater Recycler System, Planning Areas PA-3, PA-5, PA-6, PA-9, PA-10,
and PA-13, Robertson Ranch, Carlsbad Tract No. 13-03, Carlsbad, California, Project No.
133023-03, dated July 23, 2015.
LGC Valley, Inc., 2015d, Geotechnical Post-Tension Foundation Plan Review for The Vistas
Development within Planning Area 6 (PA-6), Robertson Ranch, Carlsbad Tract No. 13-03,
Carlsbad, California, Project No. 133023-06, dated August 4, 2015.
LGC Valley, Inc., 2015e, Geotechnical Post-Tension Foundation Plan Review for The Vistas
Development within Planning Area 6 (PA-6), Robertson Ranch, Carlsbad Tract No. 13-03,
Carlsbad, California, Project No. 133023-06, dated October 21, 2015.
LGC Valley, Inc., 2015f, Geotechnical Post-Tension Foundation Plan Review for The Terraces
Development within Planning Areas 9 and 10 (PA-9 and PA-b), Robertson Ranch, Carlsbad
Tract No. 13-03, Carlsbad, California, Project No. 133023-06, dated November 23, 2015.
LGC Valley, Inc., 2015g, Presaturation Recommendations Concerning the Proposed Single-Family
Residential Structures of The Vistas Development, Lots 1 through 23 of Planning Area PA-
13 and Lots 158 through 244 of Planning Area PA-6, Robertson Ranch, Carlsbad Tract No.
13-03, Carlsbad, California, Project No. 133023-06, dated December 2, 2015.
LGC Valley, Inc., 2015h, Presaturation Recommendations Concerning the Proposed Single-Family
Residential Structures, The Bluffs, Lots 25 through 60 of Planning Area PA-5, Robertson
Ranch, Carlsbad Tract No. 13-03, Carlsbad, California, Project No. 133023-06, dated
December 9, 2015.
LGC Valley, Inc., 2015i, Presaturation Recommendations Concerning the Proposed Single-Family
Residential Structures, The Terraces, Lots 252 through 326 of Planning Areas PA-9 and PA-
10, Robertson Ranch, Carlsbad Tract No. 13-03, Carlsbad, California, Project No. 133023-
06, dated December 9, 2015.
LGC Valley, Inc., 2015j, Geotechnical Post-Tension Foundation Plan Review for The Bluffs
Development within Planning Area 5 (PA-5), Robertson Ranch, Carlsbad Tract No. 13-03,
Carlsbad, California, Project No. 133023-06, dated December 22, 2015.
LGC Valley, Inc., 2016a, Updated Corrosivity Results, Planning Areas PA-5, PA-9, and PA-b,
Robertson Ranch, Carlsbad Tract No. 13-03, Carlsbad, California, Project No. 133023-09,
dated January 27, 2016.
LGC Valley, Inc., 2016b, Geotechnical Post-Tension Foundation Plan Review for The Terraces
Development within Planning Areas 9 and 10 (PA-9 and PA-10), Robertson Ranch, Carlsbad
Tract No. 13-03, Carlsbad, California, Project No. 133023-11, dated February 1, 2016.
Project No. 133023-03 Page A-2 February 3, 2016
References ('continued)
Nexus eWater, 2015, Recycler System Standard Drawings, 9 Sheets, dated April 30, 2015.
O'Day Consultants, 2014a, Vesting tentative map for Carlsbad Tract No. 13-03-2, 23 Sheets, dated
January 16, 2014.
O'Day Consultants, 2014b, Grading plans for Rancho Costera, Robertson Ranch West Village,
Carlsbad Tract No. 13-03, Drawing No. 480-3A, 44 Sheets, dated August 25, 2014.
Post-Tensioning Institute, 2006, Design of post tensioned slabs-on-ground, Third Addition,
Addendum 1 dated May 2007, and Addendum 2 dated May 2008, with errata February 4, 2010.
Specialty Steel, 2015, Post-Tension Plans, Details, and General Notes for The Bluffs (PA-5) at
Robertson Ranch, Carlsbad, California, Reference No. 4302, dated December 17, 2015.
Specialty Steel, 2016, Post-Tension Plans, Details, and General Notes for The Terraces at Robertson
Ranch, PA-9 and PA-b, Carlsbad, California, Reference No. 4301, dated November 20, 2015
with Delta 1 Dated January 29, 2016.
Suncoast Post-Tension, 2015, Post-Tension Plans, Details, and General Notes for The Vistas at
Robertson Ranch, PA-6, Carlsbad, California. Project No. 15-6428, dated August 3, 2015 Delta
1 dated October 8, 2015.
United States Geological Survey (USGS), 2008a, "2008 National Seismic Hazard Maps - Fault
Parameters" retrieved from:
http ://geohazards.usgs.gov/cfusion/hazfaults search/hf search main .cfm
USGS, 2008b, "2008 Interactive Deaggregations (Beta)," retrieved from:
https://geohazards.usgs.gov/deaggint12008/
USGS, 2013, U.S. Seismic Design Maps, retrieved from:
http://aeohazards.usas.gov/designmqps/us/batch.php#csv
Project No. 133023-03 Page A-3 February 3, 2016
APPENDIX B
Laboratory Testing Procedures and Test Results
Expansion Index Tests: The expansion potential of selected materials was evaluated by the Expansion
Index Test, U.B.C. Standard No. 18-I-13. Specimens are molded under a given compactive energy to
approximately the optimum moisture content and approximately 50 percent saturation or approximately
90 percent relative compaction. The prepared 1-inch thick by 4-inch diameter specimens are loaded to
an equivalent 144 psf surcharge and are inundated with tap water until volumetric equilibrium is
reached. The results of these tests are presented in the table below:
Test Representative Lots Sample Description Expansion Expansion
Location Index Potential
Lot 55 Lots 55-59 Pale brown fine SAND 11 Very Low
Lot 60 Lots 60 & 68-70 e Medium brown silty to clayey 70 Medium SAND
Lot 221 Lots 214-225 Pale orange brown silty fine 34 Low SAND
Lot 240 Lots 234-244 Pale gray brown silty fine SAND 10 Very Low
Lot 302 Lots 299-307 e Olive green sandy CLAY/clayey 89 Medium SAND
Lot 309 Lots 308-3 16 Pale olive green silty to clayey 86 Medium SAND
Lot 321 Lots 3 17-326 Medium olive brown clayey fine 76 Medium SAND
Project No. 133023-03 Page.B-1 February 3, 2016
Laboratory Testinr Procedures and Test Results (continued)
Soluble Sulfates: The soluble sulfate contents of selected samples were determined by standard
geochemical methods (Caltrans 417). The test results are presented in the table below:
Test
Location Sample Description Sulfate Content
(% by Weight)
Potential Degree
of Sulfate
Attack*
PA-5 Pale gray silty fine SAND 0.016 Negligible
PA-5 Light grayish brown silty fine SAND 0.033 Negligible
PA-6 Medium brown silty clayey SAND 0.025 Negligible
PA-9 Pale yellow brown clayey SAND 0.071 Negligible
PA-10 Olive green silty to sandy CLAY 0.056 Negligible
' Per ACI 318R-08 Table 4.3.1.
Chloride Content: Chloride content was tested in accordance with Caltrans Test Method (CTM)
422. The results are presented below:
Test
Location Sample Description Chloride Content
(ppm)
Potential Degree of
Chloride Attack*
PA-5 Pale gray silty fine SAND 110 Negligible
PA-5 Light grayish brown silty fine SAND 220 Negligible
PA-6 Medium brown silty clayey SAND 205 Negligible
PA-9 Pale yellow brown clayey SAND 175 Negligible
PA-10 Olive green silty to sandy CLAY 230 Negligible
Extrapolation from California Test Method 532, Method for Estimating the Time
to Corrosion of Reinforced Concrete Substructures and previous experience
Project No. 133023-03 Page B-2 February 3, 2016
Laboratory Testing Procedures and Test Results (continued)
Minimum Resistivity and pH Tests: Minimum resistivity and pH tests were performed in general
accordance with CTM 643 and standard geochemical methods. The electrical resistivity of a soil is a
measure of its resistance to the flow of electrical current. As results of soil's resistivity decreases
corrosivity increases. The results are presented in the table below:
Test Sample Description
Minimum
Resistivity Potential Degree
Location (ohms-cm) of Corrosivity*
PA-5 Pale gray silty fine SAND 1500 Corrosive
PA-5 Light grayish brown silty fine SAND 570 Severely
Corrosive
PA-6 Medium brown silty clayey SAND 640 Severely
Corrosive
PA-9 Pale yellow brown clayey SAND 800 Severely
Corrosive
LPA-10 Olive green silty to sandy CLAY 360 Severely
Corrosive
* NACE Corrosion Basics
Project No. 133023-03 Page B-3 February 3, 2016
LGC Valley, Inc.
Geotechnical Consulting
AS-GRADED REPORT OF ROUGH-GRADING,
LOTS 1 THROUGH 24 OF PA-13, PA-3 AND PA-6
MODEL LOT COMPLEXES, AND PA-4
RECREATION CENTER, ROBERTSON RANCH,
CARLSBAD TRACT NO.13-03,
CARLSBAD, CALIFORNIA
Project No. 133023-03
Dated: August 7, 2015
Prepared For:
Toll Brothers
725 Town and Country Road, Suite 500
Orange, California 9286
2420 Grand Avenue, Suite F2 • Vista • CA 92081 (760) 599-7000 • Fax (760) 599-7007
IL=2 LGC Valley, Inc.
Geotechnical Consulting
August 7, 2015 Project No. 133024-03
Mr. Peter Kim
Toll Brothers
725 Town and Country Road, Suite 500
I Orange, California 92868
Subject: As-Graded Report of Rough-Grading, Lots 1 Through 23 of PA-13, PA-3 and PA-6 Model
Lot Complexes, and PA-4 Recreation Center, Robertson Ranch, Carlsbad Tract No. 13-03, I Carlsbad, California, California
In accordance with your request and authorization, LGC Valley, Inc. (LGC) has provided geotechnical services
during the rough-grading operations for Lots 1 through 24 of Planning Area PA-13, Lots 101 through 104 of
Planning Area PA-3, Lots 206 through 211 of Planning Area PA-6, and the Recreation Center of Planning Area
PA-4 of the Robertson Ranch project (Carlsbad Tract No. 13-03) located within the City of Carlsbad,
California. Lots 101
through 104 of Planning Area PA-3 and Lots 206 through 211 of Planning Area PA-6 will
be the model lot complexes for the respective planning areas. Planning Area PA-4 consists of a sheet-graded
pad that ultimately will contain the Robertson Ranch recreation center. The accompanying as-graded report of
rough-grading summarizes our observations, field and laboratory test results, and the geotechnical conditions
encountered during grading of the subject site.
The rough-grading operations for the subject areas were performed in general accordance with previously
published project geotechnical reports (Appendix A), geotechnical recommendations made during the course of
grading, and the City of Carlsbad grading requirements. It is our professional opinion that the subject site is
suitable for its intended use provided the recommendations included herein and in the project geotechnical
reports are incorporated into the fine-grading, design, and construction of the proposed development and
associated improvements. As of the date of this report, the rough-grading operations for the subject areas of the
Robertson Ranch project are essentially complete.
If you have any questions regarding our report, please contact this office. We appreciate this opportunity to be
of service.
Respectfully Submitted,
LGC Valley, Inc.
,a- —
Randall Yaer, CEG 1612
Senior Project Geologist
( /iZ\ 9\
NO. Jrb'12 'Ai$ Cr IrTr CETIFED 3\ —I
ENGINEERING i * * GEO16 .:
EXP.
N OF C1
Basil Hattar, GE 2734
Principal Engineer
No. 2734 \\%j
Exp.6130116 j
OF C
RKW/BIH
Distribution: (1) Addressee
(8) Toll Brothers; Attention Ms. JoAnn Epstine
2420 Grand Avenue, Suite F2 • Vista • CA 92081 '(760) 599-7000 • Fax (760) 599-7007
TABLE OF CONTENTS
Section Pa e
1.0 INTRODUCTION ........................................................................................................................................ 1
2.0 SUMMARYOFROUGH-GR4DI7VG OPERA TIONS................................................................................2
2.1 As-Graded Conditions ................................................. .......................................................................2
2.2 Site Preparation and Removals........................................................................................................4
2.3 Stability Fills ............................................ ........................................................................................4
2.4 Subdrain Installation ................................. .......................................................................................4
2.5 Cut/Fill Transition Conditions .........................................................................................................5
2.6 Fill Placement ........................................... ........................................................................................5
2.7 Laboratory Testing ................................... ........................................................................................5
2.8 Field Density Testing ................................ .........................................................................................6
2.9 Graded Slopes..................................................................................................................................6
3.0 CONCLUSIONS .......................................................................................................................................... 7
3.1 General............................................................................................................................................7
3.2 Summary of Conclusions ............... . ................................................................................................. 7
4.0 RECOMMENDATIONS ............................................................................................................................... 9
4.1 Earthwork........................................................................................................................................9
4.2 Site Preparation ............................................................................................................................... 9
4.3 Excavations......................................................................................................................................9
4.4 Fill Placement and Compaction....................................................................................................10
4.5 Preliminary Foundation Recommendations.................................................................................10
4.6 Subdrain Outlet Maintenance........................................................................................................11
4.7 Control of Surface Water and Drainage ....................................................................................... 11
5.0 LIMITATIONS...........................................................................................................................................13
LIST OF TABLES. APPENDICES. AND ILLUSTRATIONS
Figures and Plates
Plates 1 and 2 - As-Graded Geotechnical Map (Rear-of-Text)
Plates 3 and 4 - Field Density Test Location Map (Rear-of-Text)
Appendices
Appendix A - References
Appendix B - Laboratory Testing Procedures and Test Results
Appendix C - Summary of Field Density Test Results
Project No. 133023-03 Page i August 7 2015
1.0 INTRODUCTION
In accordance with your request and authorization, LGC Valley, Inc. (LGC) has provided geotechnical
services during the rough-grading operations for Planning Areas PA-3, PA-4, PA-6 and PA-13 of the
Robertson Ranch project (Carlsbad Tract No. 13-03) located within the City of Carlsbad, California. This as-
graded report summarizes our observations, field and laboratory test results, and the geotechnical conditions
encountered during grading of the model complexes within PA-3 and PA-6, the recreation area of PA-4, and
Planning Area PA-13. The subject rough-grading operations were performed in general accordance with
previously published project geotechnical reports (Appendix A), geotechnical recommendations made
during the course of grading, and the City of Carlsbad grading requirements.
As of this date, the rough-grading operations for Lots 101 through 104 of PA-3, PA-4, Lots 206 through 211
I of PA-6, and PA-13 are essentially complete. However, Planning Area PA-4 is currently sheet-graded and
will need to be fine-graded in order to construct the planned recreation building pad, pool, driveway/parking
area and other anticipated site improvements. A final as-graded report documenting the additional grading
I operations (i.e. fine grading) and providing addendum and/or additional geotechnical recommendations
relative to the proposed development should be prepared upon completion of the future grading operations.
The Rough Grading Plans for the Robertson Ranch project, prepared by O'Day Consultants (O'Day, 2014b),
were utilized as a base map to present the as-graded geotechnical conditions and approximate locations of the
field density tests. The As-graded Geotechnical Map (Plates 1 and 2) and the Field Density Test Location
Map (Plates 3 and 4) are presented in the pocket at the rear of the text.
Lots 101 through 104 of PA-3, PA-4, and Lots 206 through 211 of PA-6 are located in the central portion of
I the Robertson Ranch project while PA-13 is located in the extreme eastern portion near the intersection of
El Camino Real and Cannon Road. The PA-3 model complex will includes Lot 101 through 104 on the
south side of Nelson Court between Glasgow Drive and Wellspring Street. The PA-6 model complex will
I
include Lot 206 through 211 on the east side of Wellspring Street north of Robertson Road. The Robertson
Ranch Recreation Center, Planning Area PA-4, is located on the north side of Robertson Road and east of
Wellspring Street. PA-13 is located along the south side of Glen Avenue and west of Wind Trail Way.
I Ultimately, development of the entire Robertson Ranch project will include the construction of 328 single-
family residential lots within six single-family residential planning areas (Planning Areas PA-3, PA-5, PA-
6, PA-9, PA-10 and PA-13), park sites, a recreation center (PA-4), a multi-family residential development
(PA-7 and a portion of PA-8) a retail center (PA- 11), and a senior housing development (a portion of PA-
8), along with associated retaining walls, slopes, storm water retention basins, interior roads and the
I
improvement of El Camino Real between Cannon Road and Tamarack Avenue. The rough-grading
operations for Lots 101 through 104 of PA-3, PA-4, Lots 206 through 211 of PA-6, and PA-13 were
performed as a part of grading operations for the entire Robertson Ranch Development between September
I
2014 and May 2015.
Project No. 133023-03 Page 1 August 7, 2015
I
2.0 SUMMARY OFROUGH-GRAL)ING OPERATIONS
Rough-grading of the subject site began on September 5, 2014 and was essentially completed as of May 15,
2015. The grading operations were performed under the observation and testing services of LGC Valley, Inc.
Our field technicians were onsite on a full-time basis during the grading operations while our field geologist
was onsite on a periodic basis. The rough-grading operations included:
1) Removal and off-site disposal of vegetation and miscellaneous debris;
The removal of potentially compressible soils including alluvium, colluvium, topsoil, undocumented
I fill, desiccated existing documented fill, and weathered soils to competent terrace deposits or
formational material;
Overexcavation of cut/fill transition conditions within the limits of the planned buildings;
I 4) Overexcavation of buried cut/fill transition conditions such that the resulting fill differential beneath
the proposed building pads was less than a 3:1 (maximum fill thickness to the minimum fill
thickness);
I S) Preparation of areas to receive fill;
The placement of subdrains in the canyon bottoms;
Excavation of formational material; and
I 8) The placement of compacted fill soils creating the graded pads and adjacent slopes.
Grading operations consisted of the placement of fill up to approximately 45 feet in depth within the model
I lot complex of PA-3 and up to 20 feet in depth within the model lot complex of PA-6, PA-4, and PA-13.
Both the model complexes and PA-13 consisted entirely of fill areas while the northwest portion of PA-4
was in a design cut area with up to 10 feet of design cuts. The cut/fill transition conditions present within the
I
limits of the building pad and pool of PA-4 along the cut/fill transition, as shown on the rough grading plans
(O'Day, 2014b), were overexcavated a minimum of 5 to 8 feet in depth and to a distance of at least 10 feet
outside the planned building or pool limits. During the rough-grading operations, remedial grading was also
I performed so that the fill differentials beneath the proposed building pads were less than a 3:1 (maximum fill
thickness to the minimum fill thickness). The as-graded geotechnical conditions are presented on the As-
Graded Geotechnical Map (Plates 1 and 2).
2.1 As-Graded Conditions
The as-graded conditions encountered during grading of the site were essentially as anticipated. In the
vicinity of the model lot complexes and PA-4, alluvium and colluvium were encountered within the
lower portion of the canyon running in a northwest-southeast direction while formational material was
encountered on the slopes and at design cut grade below a thin veneer of topsoil and weathered soils.
Planning Area PA-13 had been previously graded in 2008 under the observation and testing of
GeoSoils. The previous grading included the removal of compressible soils, placement of fill, and
excavation of the terrace deposits within PA-13 creating a sheet-graded pad (GeoSoils, 2008).
Processing of the sheet-graded pad in order to receive additional fill involved removing the upper 2 to
4 feet of the existing soil (i.e. documented fill and terrace deposits). No, rotational, other unstable
slope instabilities or landslides were observed during the site earthwork operations.
Project No. 133023-03 Page 2 August 7, 2015
All unsuitable and potentially compressible soils were removed prior to fill placement. This included
alluvium, colluvium, undocumented fill (associated with the past agricultural operations), desiccated
documented fills (within PA-13), and weathered terrace and formational materials. The alluvium and
colluvium typically consisted of light brown to brown silty fine sands, sandy clays and clayey sands
derived from the terrace deposits and the formational material and were found to be very low to
highly expansive, porous, and contained scattered organics. Removals of alluvium up to
approximately 20 feet in depth were made within the northwest-southeast trending canyon in the
vicinity of Lots 102 to 104 of PA-6. Removals of the colluvium, on the order of 2 to 6 feet, were
made on the middle and lower portions of the hillsides on the site. Removals of the desiccated
documented fill soils and weathered terrace deposits within PA-13 were made to a depth of 2 to 4
feet below the previous site grades.
Terrace or older alluvial flood-plain deposits were encountered PA- i 3 and consisted of silty fine to
I medium sand to sandy-silty clay with minor gravels. Bedding within the terrace deposits was
mainly massive to indistinct; however, a few sand beds that gently dipped to the west and north on
the order of 5 degrees or less were encountered. The nature of the contact between the terrace
I deposits and formational material, where observed, was a relatively sharp contact with a near
horizontal orientation.
-
I The formational material encountered in the vicinity of the model lot complexes and PA-4 consisted
of the Santiago Formation. The material was found to be massively bedded to cross-bedded silty
sandstones and minor clayey sandstones and sandy siltstones. The siltstones generally were olive ' green and orange brown, damp to moist, stiff to hard, moderately fractured and sheared. The
sandstone generally consisted of light olive green, light brown and pale orange brown (where iron-
oxidized stained), damp to moist, dense to very dense, silty very fine to medium grained sandstone.
I The majority of the Santiago material encountered within Robertson Ranch consisted of silty fine
sands. Bedding within the Santiago Formation was highly variable, but overall, generally dipped 2
to 15 degrees to the west-southwest.
A minor fault zone was geologically mapped in the western portion of PA-13 trending in a general
northeast-southwest direction, dipping 50 to 60 degrees to the west. The short, somewhat, sinuous
fault was only observed within the terrace deposits and appeared to die out to the north and south of
PA- 13. The fault was also encountered by GeoSoils during the prior grading operations of PA- 13.
The mapping by GeoSoils in 2008, indicated that the fault was observed to die out in the cut slope
between PA-13 and PA-14 (to the north) and could not be traced south of PA-13 for more than
approximately 350 feet (GeoSoils, 2008). Based on our analysis during the current grading
operations and review of the as-graded report by GeoSoils (GeoSoils, 2008) it is our professional
opinion that the fault in not active; and therefore is not a constraint to development. The
approximate location of the fault is shown on the As-Graded Geotechnical Map (Plate 1).
No groundwater was encountered during the grading of the subject areas. However, unanticipated
seepage conditions may occur after the completion of grading and establishment of site irrigation
and landscaping. If these conditions should occur, steps to mitigate the seepage should be made on
a case-by-case basis.
Project No. 133023-03 Page 3 August 7 2015
2.2 Site Preparation and Removals
Prior to grading, the site was cleared of light vegetation and other miscellaneous debris and the
material was disposed of at an offsite facility. Undocumented fill, topsoil, alluvium, colluvium,
I desiccated documented fill, weathered terrace soils and formational material were removed down to
competent material (i.e. dense unweathered terrace or formational material). Remedial removals on
site, below the existing ground surface, ranged from approximately 2 to 20 feet in depth. The
I thickness of compacted fills placed during this recent rough-grading operation, to achieve design
rough grades (or sheet-graded pad elevations), ranged from 0 to approximately 45 feet.
I Following the remedial removals or overexcavations, areas to receive fill were scarified
approximately 6-inches, moisture-conditioned, as needed, to obtain a near-optimum moisture content
and compacted to a minimum 90 percent relative compaction (for fills of approximately 40 feet or
I less from design grades) or 93 percent relative compaction (for engineered fill below approximately
40 feet from design finish grades), as determined by ASTM Test Method D6938 (i.e. the nuclear
gauge method).
2.3 Stability Fills
I Stability fills were constructed to stabilize the exposed blocky claystone/siltstone and/or adverse (i.e.
out-of-slope) geologic conditions present within the Santiago Formation. The stability fill keys were
I
excavated to a width of approximately 15 feet and a minimum depth of 3 to 5 feet below the toe-of-
slope. The keyway bottom was angled at least 2 percent into-the-slope.
I
The stability fill front cuts were excavated near vertical while the back-cuts were excavated at an
approximate 1:1 (horizontal to vertical) slope inclination. A stability fill was excavated along the
proposed slope on the west side of PA-4 and the location is presented on the As-graded Geotechnical
I
Map (Plate 2).
2.4 Subdrain Installation
Canyon and stability fill subdrains were installed under the observation of a representative of LGC in
general accordance with the planned locations of the approved geotechnical report, and the standard
details (LGC, 2014a). After the potentially compressible material in the canyons were removed to
competent material or when compacted fill was placed over competent material to obtain flow to a
suitable outlet location, a subdrain was installed along the canyon bottom.
- The canyon subdrains consisted of a 6-inch diameter perforated pipe surrounded by a minimum of 9-
cubic feet (per linear foot) of crushed 3/4-inch gravel wrapped in Mirafi 140N filter fabric. In addition
to the canyon subdrains, subdrains were also installed along the bottom backside of the stability fill
keys. The stability fill subdrains consisted of a 4-inch diameter perforated pipe surrounded by a
minimum of 3-cubic feet (per linear foot) of clean 3/4-inch gravel wrapped in Mirafi 140N filter
I fabric.
Project ATo. 133023-03 Page 4 August 7 2015
I
The canyon and stability fill subdrains were placed with a minimum 1-percent fall (2-percent or
I greater where possible) to a suitable outlet location. The location of the subdrains placed during the
mass grading operations for the project were surveyed by the project civil engineer. The subdrain
locations are presented on the As-graded Geotechnical Map (Plate 2).
2.5 Cut/Fill Transition Conditions
Based on the as-graded conditions, the cut/fill transition condition present within the limits of the
building pad and pool in PA-4, as shown on the rough grading plans (O'Day, 2014b), were
overexcavated a minimum of 5 feet in depth beneath the building and 8 feet in depth beneath the pool.
The overexcavation extended to a distance of at least 10 feet outside the planned building or pool
limits. During the rough-grading operations, remedial grading was also performed so that the fill
differential beneath the proposed building pads was less than a 3:1 (maximum fill thickness to the
minimum fill thickness).
2.6 Fill Placement
After processing the areas to receive fill, native soil was generally spread in approximately 8-inch
loose lifts, moisture-conditioned as needed to attain near-optimum moisture content, and compacted
to at least 90 or 93 percent of the maximum dry density determined in accordance with ASTM Test
Method D1557. Fill soils less than 40 feet below the design finish grades were compacted to a
minimum 90 percent relative compaction while fill soils greater than 40 feet below the design finish
grades were compacted to a minimum 93 percent relative compaction. Compaction was achieved by
use of heavy-duty construction equipment. Areas of fill in which either field density tests indicated
less than 90 or 93 percent relative compaction or the soils exhibited nonuniformity and/or showed an
inadequate or excessive moisture content, were reworked, recompacted, and retested until a minimum
90 or 93 percent relative compaction and near-optimum moisture content was achieved.
2.7 Laboratory Testin2
Maximum dry density tests of representative on-site soils were performed (by others during the
previous investigation and by LGC during the current rough-grading operations) in general
accordance with ASTM Test Method D1557. Expansion potential, soluble sulfate content, and
corrosion testing of representative finish grade soils within the subject planning areas were performed
(with the exception of Planning Area PA-4). The near-surface soils have a very low to high expansion
potential; a negligible soluble sulfate content; are moderate to severely corrosive to buried metals
based on the minimum soil resistivity values; and are corrosive to buried metals and reinforcing
steel in concrete based on the chloride concentrations. The laboratory test results are presented in
Appendix B.
I
Project Mo. /33023-03 Page 5 August ? 20/5
2.8 Field Density Testing
Field density testing was performed using the Nuclear-Gauge Method (ASTM Test Method
D6938). The approximate test locations are shown on the Field Density Test Location Maps (Plates
3 and 4). The results of the field density tests are summarized in Appendix C. The field density
testing was performed in general accordance with the applicable ASTM standards and the current
standard of care in the industry. In-situ soil density testing is intended to verify the effectiveness of
the earthmoving operation in general and is performed on a spot-check basis; as such, some
variations in relative compaction should be expected from the results documented herein.
2.9 Graded Slopes
Manufactured fill slopes withinthe subject areas were surveyed by the civil engineer and constructed
with slope inclinations of 2:1 (horizontal to vertical) or flatter. Permanent graded fill slopes adjacent
to or within the subject areas range from approximately 5 to 20 feet in height. There are no
permanently graded cut slopes within or adjacent to the subject areas. The on-site fill slopes are
considered grossly and surficially stable from a geotechnical standpoint (under normal
irrigation/precipitation patterns) provided the project geotechnical recommendations are
incorporated into the fine-grading, post-grading, construction, and post-construction phases of site
development.
Project 1'/o. 133023-03 Page 6 August 7 2015
3.0 CONCLUSIONS
3.1 General
The rough-grading of Lots 101 through 104 of PA-3, PA-4, Lots 206 through 211 of PA-6, and Lots 1
through 24 of PA-13 of Robertson Ranch located within the City of Carlsbad, California was
performed in general accordance with the project geotechnical report (LGC, 2014a), geotechnical
recommendations made during the course of grading, and the City of Carlsbad grading
requirements. It is our professional opinion that the subject site is suitable for the intended use
provided the recommendations of the referenced geotechnical reports (LGC, 2014a and 2015a
through 2015i) or those provided at the completion of the future fine grading are incorporated into
the design and construction; and that proper landscaping, irrigation, and maintenance programs are
implemented. The following is a summary of our conclusions concerning the rough-grading of Lots
101 through 104 of PA-3, PA-4, Lots 206 through 211 of PA-6, and PA-13.
3.2 Summary of Conclusions
Rough-grading of Lots 101 through 104 of PA-3, PA-4, Lots 206 through 211 of PA-6, and Lots
1 through 24 of PA-13 of Robertson Ranch is essentially complete.
Geotechnical conditions encountered during the rough-grading operation were generally as
anticipated.
The geologic units encountered during the rough-grading of the site consisted of documented and
undocumented fill soils, topsoil, colluvium, alluvium, terrace deposits, and the Santiago
Formation.
Unsuitable undocumented fill soils, topsoil, colluvium, alluvium, desiccated documented fill, and
weathered terrace deposits and formational material were removed to competent formational
I
r material within the limits of grading.
Landslides or surficial slope failures were not encountered during the grading operations.
No evidence of active faulting was encountered during the site rough-grading operations within
the model complex of PA-3 and PA-6 and within the Recreation Lot of PA-4; however, minor
inactive faulting was encountered within PA-13 but is not considered a constraint to
development.
I • Ground water seepage conditions were not encountered during the subject grading operations.
Stability fills were constructed to improve the gross stability of the cut slopes exposing
I fractured and blocky formational material and/or adverse geologic conditions on the site. The
stability fill keys were excavated in accordance with the project geotechnical
recommendations.
I . Subdrains were placed in the canyon bottoms and along the heel of the stability fill keys. The
subdrains were (or will be) outletted into suitable storm drain facilities or near the toe-of-slope
of the stability fill slopes.
I
Project No. 133023-03 Page 7 August ? 20/5
I
The cut/fill transition conditions present within the limits of the building pad and pool of PA-4
were overexcavated a minimum of 5 feet beneath the building and 8 feet beneath the pool and to a
I distance of at least 10 feet outside the planned building or pool limits.
During the rough-grading operations, remedial grading was performed so that the fill differential
beneath the proposed building pads was less than a 3:1 (maximum fill thickness to the minimum
I fill thickness).
Fill soils were derived from on-site soils. Where tested, the fill soils within the site were
I
.compacted at least a 90 or 93 percent relative compaction (based on ASTM Test Method
D1557) and near-optimum moisture content in accordance with the recommendations of the
project geotechnical report (LGC, 2014a) and the requirements of the City of Carlsbad. Fill
I
soils less than 40 feet below the design finish grades were compacted to a minimum 90 percent
relative compaction while fill soils greater than 40 feet below the design finish grades were
compacted to a minimum 93 percent relative compaction. A summary of the results of the field
I density tests is presented in Appendix C.
Due to the dense nature of the on-site soils, it is our professional opinion that the liquefaction
hazard at the site is considered low.
I . Representative testing of the finish grade soils on the building pads of Lot 1 through 24, 101
through 104, and 206 through 211 indicated the near-surface soils have a very low to high
expansion potential. The test results are presented in Appendix B.
The potential for soluble sulfate attack on concrete in contact with the finish grade soils of Lot
1 through 24, 101 through 104, and 206 through 211 is considered negligible based on AC!
Criteria (ACI 318R-05 Table 4.3.1). The soluble sulfate content test results are included in
I Appendix B.
Representative testing of the finish grade soils on the building pads of Lot 1 through 24, 101
I. through 104, and 206 through 211 was found to be moderately corrosive to corrosive to ferrous
metals. The test result is presented in Appendix B.
Expansion potential or corrosion testing of representative finish grade soils of Planning Area
I PA-4 was not performed; however, based on our observations during the site grading operations
and test results of similar soils in other portions of the Robertson Ranch project, we anticipate
that the soils within PA-4 will have a very low to low expansion potential, a negligible sulfate
I content and will be moderately corrosive to corrosive to buried metals. These assumptions
should be confirmed after the completion of the fine-grade operations of the recreation center.
It is our professional opinion that the slopes of the development are considered to be grossly
I and surficially stable, as constructed, under normal irrigation/precipitation patterns, provided
the recommendations in the project geotechnical reports are incorporated into the post-grading,
construction and post-construction phases of site development.
I
Project No. 133023-03 Page 8 August 7, 2015
4.0 RECOMMENDATIONS
4.1 Earthwork
We anticipate that future earthwork at the site will consist of site preparation, fine-grading, utility
trench excavation and backfill, retaining wall backfill, and street/driveway and parking area
pavement section preparation and compaction. We recommend that the earthwork on site be
performed in accordance with the geotechnical recommendations presented in the project
preliminary geotechnical report (LGC, 2014a), recommendations provided after the completion of
the fine-grading operations within Planning Area PA-4, and the City of Carlsbad grading
requirements.
4.2 Site Preparation
During future grading of PA-4, the areas to receive structural fill or engineered structures should be
cleared of surface obstructions, potentially compressible material (such as desiccated fill soils or
weathered formational material), and stripped of vegetation. Vegetation and debris should be
removed and properly disposed of off-site. Holes resulting from removal of buried obstructions that
extend below finish site grades should be replaced with suitable compacted fill material. Areas to
receive fill and/or other surface improvements should be scarified to a minimum depth of 12
inches, brought to optimum moisture condition, and recompacted to at least 90 percent relative
compaction (based on ASTM Test Method D1557).
If the length of time between the completion of grading and the construction of the development is
longer than six months, we recommend that the building pads be evaluated by the geotechnical
consultant and, if needed, the finish grade soils on the building pads should be scarified a minimum
of 12 inches, moisture-conditioned to optimum moisture-content and recompacted to a minimum
90 percent relative compaction (based on ASTM Test Method D1557).
4.3 Excavations
Excavations of the on-site materials may generally be accomplished with conventional heavy-duty
earthwork equipment. It is not anticipated that blasting will be required or that significant quantities of
oversized rock (i.e. rock with maximum dimensions greater than 8 inches) will be generated during
future grading. However, localized cemented zones within the cut areas may be encountered on the
site that may require heavy ripping and/or removal. If oversized rock is encountered, it should be
placed in accordance with the project geotechnical recommendations (LGC, 2014a), hauled offsite, or
placed in non-structural or landscape areas.
I Temporary excavations maybe cut vertically up to five feet. Excavations over five feet should be slot-
cut, shored, or cut to a 1:1 (horizontal to vertical) slope gradient. Surface water should be diverted
I
away from the exposed cut, and not be allowed to pond on top of the excavations. Temporary cuts
should not be left open for an extended period of time. Planned temporary conditions should be
Project No. 133023-03 Page 9 August 7 2015
reviewed by the geótechnical consultant in order to reduce the potential for sidewall failure. The
geotechnical consultant may provide recommendations for controlling the length of sidewall exposed.
4.4 Fill Placement and Compaction
The on-site soils are generally suitable for use as compacted fill provided they are free or organic
material, debris, and rock fragments larger than 8 inches in maximum dimension. We do not
recommend that high or very high expansive soils be utilized as fill for the building pads or as
retaining wall backfill.
All fill soils should be brought to 2-percent over the optimum moisture content and compacted in
uniform lifts to at least 90 percent relative compaction based on the laboratory maximum dry density
(ASTM Test Method Dl 557). The optimum lift thickness required to produce a uniformly compacted
fill will depend on the type and size of compaction equipment used. In general, fill should be placed
in lifts not exceeding 8 inches in compacted thickness. Placement and compaction of fill should be
performed in general accordance with current City of Carlsbad grading ordinances, sound
construction practices, and the project geotechnical recommendations.
If import soils are to be used as fill, they should be: 1) essentially free from organic matter and other
I
deleterious substances; 2) contain no materials over 6 inches in maximum dimension; 3) have a very
low to low expansion potential (i.e. an Expansion Index ranging from 0 to 50); and 4) have a
negligible sulfate content. Representative samples of the desired import source should be given to the
I
Geotechnical Consultant at least 48 hours (2 working days) before importing grading begins so that its
suitability can be determined and appropriate tests performed.
Foundation Recommendations
Lots 101 through 104 of PA-3 PA-4, Lots 206 through 211 of PA-6. and PA-13: The preliminary
foundation design recommendations applicable to the construction of the residential structures on
Lots 101 through 104 of PA-3, Lots 206 through 211 of PA-6, and Lots 1 through 23 of PA-13 were
previously provided in the our letter report entitled "Preliminary Foundation Design for the Single-
Family Residential Structures, Planning Areas PA-3, PA-5, PA-6, PA-9, PA-10, and PA-13,
Robertson Ranch", dated April 14, 2015 (LGC, 2015b) and our letter entitled "Deepened Footing
Recommendation of Building Foundation Adjacent to Proposed Nexus eWater Recycler System,
Planning Areas PA-3, PA-5, PA-6, PA-9, PA-b, and PA-13, Robertson Ranch" dated July 23, 2015
(LGC, 2015e). The previous recommendations remain applicable for the design of the proposed
structures on the subject lots.
Based on the expansion potential and corrosion laboratory testing of representative soils on the
subject lots, Lots 101 through 104 within PA-3 have a low expansion potential, Lots 206 though 211
of PA-6 have a very low expansion potential, Lots 1 through 12 of PA-13 have a high expansion
potential, and Lots 13 through 23 of PA-13 have a medium expansion potential. The finish grade soils
on Lots 101 through 104 of PA-3, Lots 206 through 211 of PA-6, and Lots 1 through 23 of PA-13 are
considered to have a negligible sulfates and are moderately to severely corrosive to buried metals.
Project No, 133023-03 Page 10 August 7, 2015
I The results of the expansion potential and corrosion testing is presented in Appendix B.
I Recreation Center PA-4: The preliminary foundation design and other recommendations relative to
the fine-grading, post-grading, and construction of the recreation center building, pool, and other
improvements were previously provided in the our letter report entitled "Review of the Proposed
I Recreation Center, Planning Area PA-4, Robertson Ranch", dated March 30,2015 (LGC, 2015a). The
previous recommendations remain applicable for the design and construction of the proposed
improvements within PA-4. Based on our observations during the site grading operations and test
I results of similar soils in other portions of the Robertson Ranch project, we anticipate that the soils
within PA-4 will have a very low to low expansion potential, a negligible sulfate content and will
be moderately corrosive to corrosive to buried metals. These assumptions should be confirmed
after the completion of the fine-grade operations of the recreation center.
4.6 Subdrain Outlet Maintenance
The approximate location of the subdrains and subdrain outlets constructed during the rough-
grading operations are identified on the As-Graded Geotechnical Map (Plate 2). All subdrain
outlets should be periodically cleared of soil cover or other potential blockage that may have
occurred since initial subdrain construction. If retaining walls are proposed along the toe-of-slope
I in the location of the stability fills/subdrain outlet locations, the existing subdrains should be tied
into the retaining wall back-drain system and/or placed into an appropriate storm drain facility.
4.7 Control of Surface Water and Draina'e
I Surface drainage should be carefully taken into consideration during fine-grading, landscaping, and
building construction. Positive drainage of surface water away from structures is very important. No
water should be allowed to pond adjacent to buildings or the top of slopes. Positive drainage may be
I
accomplished by providing drainage away from buildings at a gradient of at least 2 percent for a
distance of at least 5 feet, and further maintained by a swale of drainage path at a gradient of at least 1
percent. Where limited by 5-foot side yards, drainage should be directed away from foundations for a
I minimum of 3 feet and into a collective swale or pipe system. Where necessary, drainage paths may
be shortened by use of area drains and collector pipes. Eave gutters also help reduce water infiltration
into the subgrade soils if the downspouts are properly connected to appropriate outlets.
I The impact of heavy irrigation or inadequate runoff gradient can create perched water conditions,
resulting in seepage or shallow groundwater conditions where previously none existed. Maintaining
I
adequate surface drainage and controlled irrigation will significantly reduce the potential for
nuisance-type moisture problems. To reduce differential earth movements (such as heaving and
shrinkage due to the change in moisture content of foundation soils, which may cause distress to a
structure or improvement), the moisture content of the soils surrounding the structure should be kept
1 as relatively constant as possible.
Project No. 133023-03 . Page 11 . August 7, 2015
All area drain inlets should be maintained and kept clear of debris in order to function properly.
Rerouting of site drainage patterns and/or installation of area drains should be performed, if necessary.
A qualified civil engineer or a landscape architect should be consulted prior to rerouting of drainage.
Project No. 133023-03 Page 12 August 7, 2015
5.0 LIMITATIONS
Our services were performed using the degree of care and skill ordinarily exercised, under similar
circumstances, by reputable 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 submitted for laboratory testing, the observations made and the in-situ field testing
performed are believed representative of the entire project; however, soil and geologic conditions revealed by
excavation may be different than our preliminary findings. If this occurs, the changed conditions must be
evaluated by the project soils engineer and geologist and design(s) adjusted as required or alternate design(s)
recommended.
This report is issued with the understanding that it is the responsibility of the owner, or of his/her
representative, to ensure that the information and recommendations contained herein are brought to the
attention of the architect and/or project engineer and incorporated into the plans, and the necessary steps
are taken to see that the contractor and/or subcontractor properly implements the recommendations in the
field. The contractor and/or subcontractor should notify the owner if they consider any of the
recommendations presented herein to be unsafe.
The findings of this report are valid as of the present date. However, changes in the conditions of a
I
, property can and do occur with the passage of time, whether they be due to natural processes or the works
of man on this or adjacent properties.
I
In addition, changes in applicable or appropriate standards may occur, whether they result from legislation
or the broadening of knowledge. Accordingly, the findings of this report may be invalidated wholly or
partially by changes outside our control.
I
Project No. 133023-03 Page 13 August 7, 2015
I APPENDJX A
References
I
American Society of Civil Engineers (ASCE), 2013, Minimum design loads for buildings and other
structures, ASCE/SEI 7-10, Third Printing, 2013.
California Building Standards Commission (CBSC), 2013a, California Building Code, California
I Code of Regulations, Title 24, Part 2, Volume 1 and 2 of 2 (based on the 2012 International
Building Code).
I CBSC, 2013b, California Residential Building Code, California Code of Regulations, Title 24, Part
2.5,(based on the 2012 International Residential Code).
I CBSC, 2013c, California Green Building Standards Code, California Code of Regulations, Title 24,
Part 11.
I Dahlin Group, 2015, Site plan and perspectives, PA-4 recreation building @ Robertson Ranch, Sheet
Al-i through A1-5, dated January 8.
I GeoSoils, Inc., 2002, Geotechnical evaluation of the Robertson Ranch Property, City of Carlsbad,
San Diego County, California, W.O. 3098-Al-SC, dated January 29, 2002.
I GeoSoils, Inc., 2004, Updated geotechnical evaluation of the Robertson Ranch property, Carlsbad,
San Diego County, California, W.O. 3098-A2-SC, dated September 20, 2004.
I GeoSoils, Inc., 2008, Report of mass grading, Planning Area 12 (13.44 Acres), and Planning Area 13
(6.92 Acres), Robertson Ranch West, Carlsbad, San Diego County, California 92010, City of
Carlsbad Planning Department Application No. SUP 06-12/HDP 06-04, W.O. 5247-B1-SC,
I dated June 5.
GeoSoils, Inc., 2010, Updated geotechnical investigation for Robertson Ranch West Village,
I Carlsbad, San Diego County, California, W.O. 6145-A-SC, dated October 10, 2010.
GeoSoils, Inc., 2011, Supplement to. the updated geotechnical investigation, for Rancho Costera
I (formerly Robertson Ranch West Village), Carlsbad, San Diego County, California, W.O.
6145-Al-SC, dated June 6.
I GeoSoils, Inc., 2012, Preliminary geotechnical review of "vesting master tentative map for Rancho
Costera," 40-scale plans, sheets 1 through 21, Job No. 101307, Revised May 1, 2012, by
O'Day Consultants, W.O. 6145-A9-SC, dated May 24, 2012.
I GeoSoils, Inc., 2013, Addendum to the updated and supplemental geotechnical investigations for
Rancho Costera (formerly Robertson Ranch West Village), Carlsbad, San Diego County,
California, W.O. 6145-AlO-SC, dated July 16, 2013.
Project No, 133023-03 Page A-I August 7 2015
References (continued)
LGC Valley, Inc., 2014a, Geotechnical and environmental recommendations for Robertson Ranch
West, Carlsbad Tract No. 13-03, Carlsbad, California, Project Number 133023-03, dated
April 29, 2014.
LGC Valley, Inc., 2614b, Change of Geotechnical Consultant, Robertson Ranch West Project,
Carlsbad Tract No. 13-0, Carlsbad, California, Project No. 133023-03, dated May 6, 2014.
LGC Valley, Inc., 2015a, Geotechnical review of the proposed recreation Center, Planning Area PA-
4, Robertson Ranch, Carlsbad Tract No. 13-03, Carlsbad, California, California, Project No.
133023-06, dated March 30, 2015
LGC Valley, Inc., 2015b, Preliminary foundation design for the single-family residential structures,
I Planning Areas PA-3, PA-5, PA-6, PA-9, PA-10, and PA-13, Robertson Ranch, Carlsbad
Tract No. 13-03, Carlsbad, California, Project No. 1.33023-06, dated April 14, 2015.
I LGC Valley, Inc., 2015c, As-graded completion letter, Lots 1 through 23, Robertson Ranch,
Carlsbad Tract No. 13-03, 4980 El Camino Real, Carlsbad, California, Project No. 133023-
I
03, dated June 9, 2015.
LGC Valley, Inc., 2015d, Preliminary Review of Building Setbacks for the Proposed Residential
Planning Areas 3, 5, 6, 9, 10, and 13, Robertson Ranch, Carlsbad Tract No. 13-03, Carlsbad,
I California, Project No. 133023-03, dated February 27, 2015, revised June 24, 2015.
LGC Valley, Inc., 2015e, Deepened Footing Recommendation of Building Foundation Adjacent to
I Proposed Nexus eWater Recycler System, Planning Areas PA-3, PA-5, PA-6, PA-9, PA-10,
and PA-13, Robertson Ranch, Carlsbad Tract No. 13-03, Carlsbad, California, Project No.
133023-03, dated July 23, 2015.
I LGC Valley, Inc., 2015f, Geotechnical Foundation Plan Review for the Proposed Recreation Center,
Planning Area PA-4, Robertson Ranch, Carlsbad Tract No. 13-03, Carlsbad, California
I Project No. 133023-06, dated July 29, 2015
LGC Valley, Inc., 2015g, Geotechnical Post-Tension Foundation Plan. Review for .The Ridge
I Development within Planning Area 3 (PA-3), Robertson Ranch, Carlsbad Tract No. 13-03,
Carlsbad, California, Project No. 133023-06, dated August 4, 2015.
I LGC Valley, Inc., 2015h, Geotechnical Post-Tension Foundation Plan Review for The Vistas
Development within Planning Area 6 (PA-6), Robertson Ranch, Carlsbad Tract No. 13-03,
Carlsbad, California, Project No. 133023-06, dated August 4, 2015.
LGC Valley, Inc., 2015i, Geotechnical Post-Tension Foundation Plan Review for The Vistas
Development within Planning Area 13 (PA-13), Robertson Ranch, Carlsbad Tract No. 13-03,
Carlsbad, California, Project No. 133023-06, dated August 4, 2015.
Project No. 133023-03 Page A-2 August 7 2015
References (continued)
I Nexus eWater, 2015, Recycler System Standard Drawings, 9 Sheets, dated April 30, 2015.
O'Day Consultants, 2014a, Vesting tentative map for Carlsbad Tract No. 13-03-2, 23 Sheets, dated
I January 16,2014.
O'Day Consultants, 2014b, Grading plans for Rancho Costera, Robertson Ranch West Village,
Carlsbad Tract No. 13-03, Drawing No. 480-3A, 44 Sheets, dated August 25, 2014.
Post-Tensioning Institute, 2006, Design of post tensioned slabs-on-ground, Third Addition,
I Addendum 1 dated May 2007, and Addendum 2 dated May 2008, with errata February 4, 2010.
Summer/Murphy & Partners, 2015, Robertson Ranch recreation center plot plan, 1 sheet, dated
I January 5.
United States Geological Survey (USGS), 2008a, "2008 National Seismic Hazard Maps - Fault
I Parameters" retrieved from:
http://geohazards.usgs.gov/cfusion/hazfaults search/hf_ search _main.cfm
I USGS, 2008b, "2008 Interactive Deaggregations (Beta)," retrieved from:
https://geohazards.usgs.gov/deaggint/2008/
I USGS, 2013, U.S. Seismic Design Maps, retrieved from:
http://geohazards.usgs.gov/designmaps/us/batch.php#csv
I
Project 7'/o. 133023-03 Page A-3 August 7, 2015
APPENDIX B
Laboratory TWOm Procedures and Test Results
Maximum Dry Density Tests: The maximum dry density and optimum moisture content of typical
materials were determined in accordance with ASTM Test Method D1557. The results of these tests are
presented in the table below.
Number
Sample Sample Description
Maximum
Dry Density
(pci)
Optimum
Moisture Content
(%)
1 Gray brown sandy CLAY 117.5 16.0
2 Greenish gray silty CLAY 102.0 21.5
3 Red brown sandy CLAY 118.0 13.5
4 Dark gray brown clayey fine SAND 123.5 11.0
5 Medium brown f-rn SAND 124.5 11.0
6 Light brown silty SAND 114.5 13.5
7 Olive gray clayey SILT 111.5 19.5
8 Pale gray silty fine SAND 115.5 14.5
9 Pale gray silty f-rn SAND 127.5 10.5
10 Medium brown clayey SAND 128.0 10.0
11 Light brown clayey SAND 122.0 12.5
12 Pale brown fine sandy CLAY to clayey
SAND 124 0 12.0
13 Pale brown fine sandy CLAY to clayey
SAND 125.5 11.0
14 Light gray silty fine SAND 117.0 15.0
Project No. 133023-03 Page B-i August 7, 2015
I
Expansion Index Tests: The expansion potential of selected materials was evaluated by the Expansion
I Index Test, U.B.C. Standard No. 18-I-B. Specimens are molded under a given compactive energy to
approximately the optimum moisture content and approximately 50 percent saturation or approximately
90 percent relative compaction. The prepared 1-inch thick by 4-inch diameter specimens are loaded to
I an equivalent 144 psf surcharge and are inundated with tap water until volumetric equilibrium is
reached. The results of these tests are presented in the table below:
Lots Numbers Sample Description Expansion
Index
Expansion
Potential
1-12 (PA-13) Brown clayey SAND 108 High
13-23 (PA-13) Brown clayey SAND 57 Medium
88-91 & 100-104
(PA-3)
Light brown silty fine
SAND 35 Low
206-211 (PA-6) Light gray silty SAND 16 Very Low
Soluble Sulfates: The soluble sulfate contents of selected samples were determined by standard
geochemical methods (Caltrans 417). The test results are presented in the table below:
Sulfate Content Potential Degree
Lot Numbers Sample Description (% by Weight) of Sulfate
Attack*
Lots 1-23 (PA-13) Light brown silty fine SAND 0.011 Negligible
Lots 10 1 - 104 (PA-3) Medium brown silty clayey 0.025 Negligible SAND
Lots 206-211 (PA-6) Pale yellow brown silty fine 0.071 Negligible SAND
* Per ACI 318R-08 Table 4.3.1.
ProjectNo. /33023-03 Page B2 August 7, 2015
Chloride Content: Chloride content was tested in accordance with Caltrans Test Method (CTM)
422. The results are presented below:
Chloride Potential Degree
Lot Numbers Sample Description Content (ppm) of Chloride
Attack*
Lots 1-23 (PA-13) Light brown silty fine SAND 270 Negligible
Lots 101-104 (PA-3) Medium brown silty clayey 205 Negligible SAND
Lots 206-211 (PA-6) Pale yellow brown silty fine 175 Negligible SAND
* Extrapolation from California Test Method 532, Method for Estimating the Time to Corrosion of
Reinforced Concrete Substructures and previous experience
Minimum Resistivity and pH Tests: Minimum resistivity and pH tests were performed in general
accordance with CTM 643 and standard geochemical methods. The electrical resistivity of a soil is a
measure of its resistance to the flow of electrical current. As results of soil's resistivity decreases
corrosivity increases. The results are presented in the table below:
Lot Numbers Sample Description
Minimum
Resistivity Potential Degree
(ohms-cm)) of Corrosivity*
Lots 1-23 (PA-13) Light brown silty fine SAND 1200 Moderately
Corrosive
Lots 101-104 (PA-3) Medium brown silty clayey 640 Corrosive SAND
Lots 206-211 (PA-6) Pale yellow brown silty fine 800 Corrosive SAND
NACE Corrosion Basics
Project No. /33023-03 Page B 3 August 7, 2015
APPENDIX C
Summary of Field Density Test Results
Prqject 7'Jo. /33023-03 Page C-i August 7, 2015
LGC Valley, Inc.
2420 Grand Avenue, Suite F2, Vista, California 92081.
760-599-7000 / Fax 760-599-7007
REPORT OF COMPACTION TEST DATA
Print Date: August 10, 2015
Project No. 133023-03
Client. Toll Brothers
Project Name: Robinson Ranch (PA3&6 Model Lots, PA-4, and PA-13)
Location: Carlsbad, CA
Reviewed by:
Test #
Nuclear
Ga ('
or Sand
Cone (S)
Test Date Test Location Soil
Type Test of
Elev ation
or Depth
in cc
Moisture (%) [ Dry Dens ity (pcf) Relative Compaction (%)
Comments Field Optimu i Field Maximum Obtained Required
1 N 9/3/2014 PA-13 Lot 21 2 CF 65.0 15% 1 21.5% 94.6 102.0 93% 90% retest on 1A
1A N 9/3/2014 PA-13 Lot 21 2 CF 65.0 21.8% 21.5% 940 102.0 92% 90% retest of 1
2 N 9/3/2014 PA-13 Lot 17 2 CF 67.0 15% 21.5% 96.2 102.0 94% 90% retest on 2A
2A N 9/3/2014 PA-13 Lot 17 2 CF 67.0 21.6% 21.5% 926 102.0 91% 90% retest of2
3 N 9/3/2014 PA-13 Lot 15 2 CF 68.0 22.6% 21.5% 94.2 102.0 92% 90%
4 N 9/3/2014 PA-13 Lot 20 1 CF 67.0 16.8% 16.0% 106.1 117.5 90% 90%
5 N 9/4/2014 PA-13 Lot 13 2 1 CF 1 69.0 24.3% 1 21.5%1 93.6 102.5 1 91% 90%
6 N 9/4/2014 PA- 13 Lot 22 3 CF 68.0 14.6% 13.5% 108.3 118.0 92% 90%
7 N 9/4/2014 PA-13 Lot 24 2 CF 67.0 20.3% 21.5% 92.8 102.0 91% 90%
8 N 9/4/2014 PA-l3 Lot l 3 CF 69.0 14.1% 13.5% 106.8 118.0 91% 90%
9 N 9/4/2014 PA-13 Lot . 3 CF . 69.0 15.4% 13.5% 107.8 118.0 91% 90%
10 N 9/4/2014 PA-13 Lot 1 CF 70.0 19.4% 16.0% 105.8 117.5 90% 90%
11 N 9/4/2014 PA-13 Lot 11 1 CF 70.0 16.3% 16.0% 107.8 117.5 92% 90%
31 N 9/12/2014 PA-13 Lot 1 CF 70.0 15.6% 1 16.0% 107.7 117.5 1 92% 90%
32 N 9/12/2014 PA-13 Lot 1 1 CF 71.0 19.7% 16.0% 108.7 117.5 93% 90%
33 N 9/12/2014 PA-13 Lot 10 1 CF 71.0 18.8% 16.0% 106.9 117.5 91% 90%
34. N 9/12/2014 PA-13 Lot 12 3 CF 70.0 14.9% 13.5% 107.1 118.0 91% 90%
35 N 9/12/2014 PA-13 Lot 23 3 CF 69.0 14.0% 13.5% 108.6 118.0 92% 90%
46 N 9/15/2014 PA-13 Lot 23 Slope 4 CF 71.0 9.9% 11.0% 114.2 123.5 92% 1 90%
'47 N 9/15/2014 PA-13 Lot 22 Slope 4 CF 72.0 12.9% 11.0%1 112.3 123.5 91% 90%
51 N 9/16/2014 PA-13 Lot 1 4 CF 71.0 11.2% 11.0% 111.6 123.5 90% 90%
52 N 9/16/2014 PA-13 Lot 4 CF 72.0 10.0% 11.0% 112.6 123.5 91% 90%
53 N 9/16/2014 PA-13 Lot 6 CF 72.0 13.7% 13.5% 106.8 114.5 93% 90%
65 N 9/17/2014 PA-13 Lot 11 5 CF' 72.0 10.5% 11.0% 117.2 124.5 94% 90%
66 N 9/17/2014 PA-13 Lot 5 CF 72.0 11.8% 11.0% 119.6 124.5 96% 90%
67 N 9/17/2014 PA-13 Lot 5 CF 71.0 10.6% 1 11.0% 120.0 124.5 96% 90%
73 N 9/17/2014 PA-13 Lot 11 1 CF 73.0 15.7% 16.0%1 105.9 117.5 90% 90%
74 N 9/17/2014 PA-13 Lot 8 4 CF 73.0 11.8% 11.0% 111.8 123.5 91% 90%
75 N 9/17/2014 PA-13 Lot 5 CF 73.0 9.8% 11.0% 115.1 124.5 92% 90%
76 N 9/17/2014 PA-13 Lot 2 5 CF 72.0 12.8% 11.0% 112.9 124.5 91% 90%
86 N 9/18/2014 PA-13 Lot 9 4 CF 73.0 12.6% 11.0% 111.7 123.5 90% 90%
87 N 9/18/2014 PA-13 Lot 4 CF 73.0 12.2% 11.0% 113.1 1 123.5 92% 1 90%
88 N 9/18/2014 PA-13 Lot.. 4 CF 73.0 13.0% 1 11.0% 113.8 123.5 92% 90%
89 N 9/18/2014 PA-13 Lot 12 5 CF 73.0 13.5% 11.0% 114.0 124.5 92% 90%
92 N 9/19/2014 PA-13 Lot 8 CF 74.0 14.8% 14.5% 107.2 115.5 93% 90%
93 N 9/19/2014 PA-13 Lot 8 CF . 74.0 15.8% 14.5% 104.9 115.5 91% 90%
94 N 9/19/2014 PA-13 Lot 4 CF 74.0 12.8% 11.0% 113.5 123.5 92% 90% 1
95 N 9/19/2014 PA-13 Lot 1 8 CF 73.0 15.5% 14.5% 106.8 115.5 92% 90%
96 N 9/19/2014 PA-13 Lot12 Slope 3 CF 74.0 14.6% 13.5%1 111.2 118.0 94% 90%
97 N 9/19/2014 PA-13 Lot 1 3 CF 74.0 15.3% 13.5% 110.2 118.0 93% 90%
100 N 9/19/2014 PA-13 Lot 3 4 CF 74.0 11.9% 11.0% 115.6 123.5 94% 90%
101 N 9/22/2014 PA-13 Lot 5 4 CF 75.0 11.4% 11.0% 114.9 123.5 93% 90%
102 N 9/22/2014 PA-13 Lot 10 4 CF 75.0 12.3% 11.0% 115.3 123.5 93% 90%
103 N 9/22/2014 PA-13 Lot 4 CF 75.0 11.8% 11.0% 117.4 123.5 1 95% 90%
104 N 9/22/2014 PA-13 Lot 4 CF 75.0 12.2% 11.0% 113.3 123.5 92% 90%
105 N 9/22/2014 PA-l3 Lot lo 4 CF 76.0 13.8% 11.0% 112.8 123.5 91% 90%
106 N 9/23/2014 PA-l3 Lot ll 4 CF 77.0 9.9% 11.0% 112.9 123.5 91% 90%
107 N 9/23/2014 PA-13 Lot 3 CF 76.0 12.5% 13.5% 107.4 118.0 91% 90%
108 N 9/23/2014 PA-13 Lot . 4 CF 1 76.0 9.9% 11.0% 116.9 123.5 95% 90%
109 N 9/23/2014 PA-13 Lot 1 4 CF 75.0 10.3% 11.0% 114.2 123.5 92% 90%
110 N 9/23/2014 PA-13 Lot 9 4 CF 78.0 10.7% 11.0% 112.3 123.5 91% 90%
111 N 9/23/2014 PA-13 Lot 6 4 CF 76.0 13.9% 11.0% 115.9 123.5 94% 90%
112 N 9/23/2014 PA-13 Lot 4 4 CF 77.0 11.3% 11.0%1 115.5 123.5 94% 90%
113 N 9/23/2014 PA-l3 Lot l 3 CF 76.0 13.8% 13.5% 107.9 118.0 91% 90%
120 N 9/24/2014 PA-13 Lot 4 CF 76.0 10.7% 11.0% 113.8 123.5 92% 90%
121 N 9/24/2014 PA-13 Lot 6 4 CF' 76.0 10.6% 11.0% 112.1 123.5 91% 90%
122 N 9/24/2014 1 PA-13 Lot 3 CF 1 78.0 12.9% 13.5% 112.0 118.0 95% 90% 1
8/11/2015
. Page 1 of 5
LGC Valley, Inc.
2420 Grand Avenue, Suite F2, Vista, California 92081
760-599-7000 / Fax 760-599-7007
REPORT OF COMPACTION TEST DATA
Print Date:
Project No.
Client.
Project Name:
Location:
Reviewed by:
August 10, 2015
133023-03
Toll Brothers
Robinson Ranch (PA3&6 Model Lots, PA-4, and PA-13)
Carlsbad, CA
=
Test #
Nuclear
auge (N)
GorSand
Cone (S)
Test Date Test Location Soil
Type Test of
Elevation
or Depth
(in feet)
I Moisture (%) I Dry Density (pct) I Relative Compaction (%)F
Comments Field IOptimurr1 Field Maximum Obtained [ Require[
123 N 9/24/2014 PA-13 Lot 11 CF 79.0 10.5% 11.0% 115.3 123.5 93% 90%
124 N 9/24/2014 PA-13 Lot 6 _3 CF 77.0 12.8% 15% 1106 118.0 94% 90%
125 N 9/24/2014 PA-13 Lot _3 - CF 77.0 13.3% 13.5% 109.9 118.0 93% 90%
139 N 9/26/2014 PA-13 Lot 9 - CF 28.0 12.0% 10% 120 127.5 95% 90%
140 N 9/26/2014 PA-13 Lot 3 - CF 79.0 16.8% 15% 12 - 118.0 93% 90%
141 N 9/26/2014 PA-13 Lot _9 - CF 79.0 11.3% 10.5% 14.7 - 127.5 90% 90%
142 N 9/26/2014 PA-13 Lot 10 _4 - CF 1 80.0 12.2% 11.0% 123 - 1 123.5 1 91% 90%
171 N 9/29/2014 PA-13 Lot 21 _3 - CF 66.0 13.4% 15% 06.9 - 118.0 91% 90%
172 N 9/29/2014 PA-13 Lot 18 3 CF 67.0 14.8% 135% 08.1 - 118.0 92% 90%
173 N 9/29/2014 PA-13 Lot 14 7 CF 68.0 19.4% 19% 02.9 - 111.5 92% 90%
174 N 9/29/2014 PA-13 Lot 13 3 CF 69.0 14.2% 13.5°h 08.0 - 118.0 92% 90%
175 N 9/29/2014 PA-13 Lot 12 4 CF 73.0 11.8% 11.0% 16.5 - 123.5 94% 90%
176 N 9/29/2014 PA-13 Lot 9 4 CF 8.0 11.2% 11.0% 15.7 - 123.5 94% 90%
177 N 9/29/2014 PA-13 Lot 6 4 1 CF 1 80.0 10.5% 11.0% 11.7 - 123.5 1 90% 90%
178 N 9/30/2014 PA-13 Lot 19 5 1 CF 68.0 9.9% 1 11.0%1 1182 124.5 95% 90%
179 N 9/30/2014 PA-13 Lot 17 4 CF 68.0 10.7% 11.0% iiao 123.5 91% 90%
180 N 9/30/2014 PA-13 Lot 15 5 CF 69.0 10.2% 11.0% 1175 124.5 94% 90%
181 N 9/30/2014 PA-13 Lot 14 5 CF 69.0 9.3% 11.0% 1190 124.5 96% 90%
182 N 9/30/2014 PA-13 Lot 14 3 CF 70.0 13.1% 15% 1089 118.0 92% 1 90%
186 N 10/1/2014 PA-13 Lot 1 4 CF 69.0 11.8% 11.0% 111.9 123.5 91% 1 90%
187 N 10/1/2014 PA-13 Lot 1 3 CF 1 67.0 13.6% 13.5% 1077 118.0 91% 90%
211 N 10/1/2014 PA-13 Lot 4 1 CF 80.0 11.1% 1 11.0% 114.3 123.5 93% 90%
212 N 10/1/2014 PA-13 Lot 8 4 CF 81.0 9.5% 11.0% iiao 123.5 91% 90%
213 N 10/1/2014 PA-13 Lot 10 3 CF 82.0 15.9% 13.5% 106.9 118.0 91% 90%
216 N 10/2/2014 PA-l3 Lot l 4 CF 71.0 13.7% 11.0% 111.2 123.5 90% 90%
217 N 10/2/2014 PA-13 Lot 1 4 CF 73.0 13.9% 11.0% 114.5 123.5 1 93% 90%
221 N 10/2/2014 PA-13 Lot 6 3 CF 81.0 14.6% 13% 1093 118.0 93% 90%
222 N 10/2/2014 PA-13 Lot 10 5 CF 83.0 12.7% 11.0% 116.7 124.5 94% 90% 1
223 N 10/2/2014 PA-13 Lot 1 5 CF 75.0 13.2% 1 11.0% 115.9 124.5 93% 90%
224 N 10/2/2014 PA-13 Lot 4 4 CF 81.0 10.3% 1 11.0% 114.7 123.5 93% 90%
225 N 10/2/2014 PA-13 Lot 8 6 CF 83.0 14.2% 15% 107.1 114.5 94% 90%
295 N 10/8/2014 PA-l3 Lot ll 7 CF 85.0 23.1% 19.5%1 100.7 111.5 90% 90%
296 N 10/8/2014 PA-13 Lot 3 5 CF 81.0 14.3% 11.0%1 115.5 124.5 1 93% 90%
297 N 10/8/2014 PA-13 Lot 1 4 CF 77.0 11.3% 11.0% 112.6 123.5 91% 90%
298 N 10/8/2014 PA-13 Lot 1 5 CF 79.0 12.0% 11.0% 115.4 124.5 93% 90% 1
306 N 10/ PA-l3 Lot ll 4 CF 84.0 12.9% 11.0% 113.7 123.5 92% 90%
307 N 10/1 PA-l3 Lot ll 3 FG -0.0 14.1% 1 13.5% 110.4 118.0 94% 90%
308 N 10/13 PA-13 Lot 10 4 FG 0.0 9.2% 11.0% 116.9 123.5 95% 90%
309 N 10/13 PA-13 Lot 9 4 FG 0.0 10.6% 11.0% 118.4 123.5 96% 90%
310 N 10/13 PA-13 Lot 8 4 FG 0.0 9.3% 11.0%1 112.7 123.5 1 91% 90%
331 N 10/13/2014 PA-13 Lot 3 FG 0.0 12.2% 13.5% 110.9 118.0 94% 90%
332 N 10/13 PA-13 Lot 3 FG 0.0 12.0% 13.5% 112.5 118.0 95% 90%
333 N 10/13 PA-13 Lot 5 3 FG 0.0 12.5% 13.5% 113.2 118.0 96% 90%
334 N 10/13 PA-13 Lot 4 4 FG 0.0 11.4% 11.0% 116.3 123.5 94% 90%
335 N 10/13 PA-13 Lot 4 FG 0.0 9.4% 11.0% 118.4 123.5 96% 90%
336 N 10/13 PA-13 Lot 2 1 FG 0.0 18.6% 16.0% 111.1 117.5 95% 90%
337 N 10/13/2014 PA-13 Lot 1 1 FG 0.0 17.9% 1 16% 1 109.6 117.5 1 93% 900
377 N 1 PA-13 Lot 12 Slope 4 - SF 82.0 11.5% 11.0% 112.9 123.5 91% 90%
378 N 1 PA- 13 Lot 23 Slope 1- SF 78.0 16.2% 16% 109.8 117.5 93% 90%
379 N 1 PA-13 Lot 24 Slope _4 - SF 70.0 14.6% 11.0% 114.0 123.5 92% 90%
429 N 10/2112014 PA-13 Lot 22 3 - CF 70.0 13.5% 15% 106.4 118.0 90% 90%
430 N 10/21/2014 PA-13 Lot 23 - - CF 70.0 16.5% 16.0% 107.8 117.5 92% 90%
448 N 10 PA-13 Lot 19 _2 - CF 70.0 22.2% 21.5% 95 102.0 94% 90%
449 N 10 PA-13 Lot 16 _2 - CF 71.0 22.8% I 21.5% 94.0 102.0 92% 90%
450 N 1024 PA-13 Lot 12 4 CF 1 75.0 11.6% 11.0% 111.5 123.5 90% 90%
526 N 10/28/2014 PA-4 South Slope 11 CF 100.0 12.9% 12% 112.1 122.0 92% 90%
551 N 10/29/2014 PA-13 Lot 24 4 CF 68.0 1 10.7% 11.0% 111.8 123.5 91% 90%
552 N 10/29/2014 PA-13 Lot 23 3 CF 70.0 1 14.9% 13.5% 109.2 118.0 93% 90%
8/11/2015 Page 2 of 5
LGC Valley, Inc.
2420 Grand Avenue, Suite F2, Vista, California 92081
760-599-7000 / Fax 760-599-7007
REPORT OF COMPACTION TEST DATA
Print Date: August 10, 2015
Project No. 133023-03
Client. Toll Brothers
Project Name: Robinson Ranch (PA3&6 Model Lots, PA-4, and PA-13)
Location: Carlsbad, CA
Reviewed by:
=
Test #
Nuclear
Gauge (N).
or Sand
Cone (S)
Test Date
_L
I ' Test Location I
Soil
Type Test of
Elevation
or Depth
. in e
Moisture (%) J Dry Density (pcf) Relative Compaction (%)
Comments . Field . Optimun I . Field
I
. Maximum . Obtained . Required
553 N 10/29/2014 PA-13 Lot 22 _3 - CF 71.0 13.8% 13.5% 108.3 118.0 92% 90%
554 N 10/29/2014 PA-13 Lot 24 4 CF 69.0 11.3% 11.0% 112.5 123.5 91% 90%
555 N 10/30/2014 PA-13 Lot 14 4 CF 71.0 10.3% 11.0% 111.7 123.5 90% 90%
556 N 10/30/2014 PA-13 Lot 17 _4 - CF 70.0 11.0% 11.0% 111.1 123.5 90% 90%
557 N 10/30/2014 PA-13 Lot 20 5 - CF 69.0 11.3% 11.0% 114.3 124.5 92% 90%
558 N 10/30/2014 PA-13 Lot 22 _3 FG 0.0 12.5% 13.5% 108.4 118.0 92% 90%
559 N 10/30/2014 PA-13 Lot 23 _3 FG 1 0.0 13.1% 1 13.5%1 106.5 118.0 1 90% 90%
560 N 10/30/2014 PA-13 Lot 24 5 - FG 0.0 10.4% 11.0% 114.2 124.5 92% 90%
561 N 10/30/2014 PA-13 Lot 12 4 FG 0.0 10.0% 11.0% 113.6 123.5 92% 90%
562 N 10/30/2014 PA-13 Lot 13 4 FG 0.0 9.5% 11.0% 112.8 123.5 91% 90%
563 N 10/30/2014 PA-13 Lot 14 _4 - FG 0.0 9.9% 11.0% 113.1 123.5 92% 90%
564 N 10/30/2014 PA-13 Lot 15 5 FG 0.0 10.8% 11.0% 113.0 124.5 91% 90%
565 N 10/30/2014 PA-13 Lot 16 _5 FG 0.0 10.7% 11.0% 112.6 124.5 90% 90%
566 N 10/30/2014 PA-13 Lot 17 _10 FG 1 0.0 9.2% 1 10.0%1 1176 128.0 1 92% 90%
567 N 10/30/2014 PA-13 Lot 18 _4 FG 0.0 11.1% 11.0% 1138 123.5 92% 90%
568 N 10/30/2014 PA-13 Lot 19 4 FG 0.0 10.7% 11.0% 114.9 123.5 1 93% 90%
569 N 10/30/2014 PA-13 Lot 20 _10 FG 0.0 11.4% 10.0% 117.3 128.0 92% 90%
570 N 10/30/2014 PA-13 Lot 21 _4 - FG 0.0 10.8% 11.0% 111.2 123.5 90% 90%
633 N 11/6/2014 PA-4 _9 CF 118.0 12.3% 10.5% 117.3 127.5 92% 90%
634 N 11/6/2014 PA-4 9 CF 117.0 13.1% 105% 116.1 127.5 91% 90%
694 N 11/12/2014 PA-8 West Slope 10 CF 137.0 1 11.3% 10.0%1 1202 128.0 94% 90%
697 N 11/13/2014 PA-8 West Slope 10 CF 139.0 10.9% 10.0% 119.5 128.0 93% 90%
717 N 11/15/2014 PA-3 Lot 153 - - CF 96.0 12.1% 11.0% 14.4 - 124.5 1 92% 90%
739 N 11/17/2014 PA-3 Lot 114 Slope - - CF 107.0 14.5% 11.0% 114.0 124.5 92% 90%
751 N 11/18/2014 PA-8 West Slope 11 CF 144.0 13.1% 12.5% 111.9 122.0 92% 90%
765 N 11/19/2014 PA-3 Lot 114 4 CF 108.0 14.1% 11.0% 111.2 123.5 90% 90%
771 N 11/19/2014 PA-6 Lot 209 - - CF 118.0 13.7% 1 10% 117.4 127.5 92% 90%
772 N 11/19/2014 PA-6 Lot 211 - - CF 120.0 13.3% 1 10% 116.1 127.5 91% 90%
787 N 11/20/2014 PA-3 Lot 103 10 CF 116.0 12.1% 10.0% 118.9 128.0 93% 90%
788 N 11/20/2014 PA-3 Lot 104 10 CF 114.0 12.3% 10.0% 117.9 128.0 1 92% 90%
804 N 11/24/2014 Robertson Rd Sta. 26+65 5 CF 110.0 13.9% 11.0% 115.5 124.5 93% 90%
807 N 11/24/2014 PA-8 6 CF 128.0 16.2% 13.5% 104.7 114.5 91% 90%
808 N 11/24/2014 PA-8 6 CF 130.0 15.1% 13.5% 106.4 114.5 93% 90%
820 N 11/25/2014 PA-8 West Slope - - CF 1 148.0 12% 11.0% 114.5 124.5 92% 90%
853 N 11/26/2014 PA-6 Lot 208 5 CF 144.0 12.4% 1 11.0% 112.3 124.5 90% 90%
854 N 11/26/2014 PA-6 Lot 209 5 CF 142.0 12.9% 11.0% 115.3 124.5 93% 90%
855 N 11/26/2014 PA-6 Lot 207 5 CF 146.0 15:1% 11.0% 113.2 124.5 1 91% 90%
872 N 12/1/2014 PA-8 5 CF 127.0 10.7% 11.0% 119.0 124.5 96% 90%
880 N 12/9/2014 Robertson Rd Sta. 26+95 1 CF 112.0 18.2% 16.0% 110.9 117.5 94% 90%
881 N 12/9/2014 Roberston Rd Sta. 26+90 1 CF 111.0 18.9% 16.0% 110.7 117.5 94% 90%
884 N 12/10/2014 PA-3 Lot 104 7 CF 119.0 20.0% 19.5% 104.5 111.5 94% 90%
885 N 12/10/2014 Wellspring St Sta. 26+00 1 - - CF 118.0 19.0% 16.0% 106.1 _117.5_5_ 90% 90%
888 N 12/10/2014 PA-6 Lot 247 5 CF 118.0 10.7% 11.0% 114.4 124.5 92% 90%
889 N 12/10/2014 Wellspring St Sta. 27+40 11 CF 117.0 16.5% 12.5%1 111.3 122.0 1 91% 90%
897 N 12/23/2014 PA-3 Lot 153 9 CF 122.0 14.2% 10.5% 116.3 127.5 91% 90% 1
898 N 12/23/2014 Roberston Rd Sta. 26+15 5 CF 123.0 15.1% 11.0% 114.7 124.5 92% 90%
899 N 12/23/2014 PA-3 Lot 103 11 CF 122.0 16.6% 12.5% 112.4 122.0 92% 90%
900 N 12/23/2014 PA-3 Lot 114 11 CF 123.0 17.0% 12.5% 111.9 122.0 92% 90%
905 N 12/11/2014 Wellspring St Sta. 26+50 5 CF 122.0 14.6% 11.0% 115.3 124.5 93% 90%
906 N 12/11/2014 PA-3 Lot 104 1 CF 123.0 18.2% 16.5% 108.5 117.5 92% 90%
931 N 12/29/2014 PA-3 Lot 104 11 CF 130.0 15.4% 12.5% 111.8 122.0 92% 90%
932 N 12/29/2014 PA-3 Lot 153 11 . CF .132.0 16.0% 12.5%1 110.0 122.0 . 90%. 90%
933 N 12/29/2014 Wellspring St Sta. 26+50 - 5 - CF 131.0 13.4% 11.0%1 115.8 124.5 93% 90%
934 N 12/29/2014 PA-6 Lot 210 5 CF 133.0 12.8% 11.0% 115.0 124.5 92% 90%
935 1 12/29/2014 PA-6 Lot 246 5 CF 1 157.0 14.0% 11.0% 115.6 124.5 93% 90%
954 N 1/5/2015 PA-3 Lot 91 Slope 9 CF 141.0 12.4% 10.5% 116.9 127.5 92% 90%
955 N 1 1/5/2015 PA-3 Lot 81 9 CF 142.0 13.2% 10.5% 115.7 127.5 910/( 90%
956 N 1 1/512015 PA-3 Lot 90 Slope 5 CF 140.0 14.1% 11.0% 113.5 1 124.5 91% 90%
8/11f2015 Page3of5
LGC Valley, Inc.
2420 Grand Avenue, Suite F2, Vista, California 92081
760-599-7000 / Fax 760-599-7007
REPORT OF COMPACTION TEST DATA
Print Date: August 10, 2015
Project No. 133023-03
Client. Toll Brothers
Project Name: Robinson Ranch (PA3&6 Model Lots, PA-4, and PA-13)
Location: Carlsbad, CA
Reviewed by:
Test #
Nuclear
Gauge (N),
or Sand
Cone (S)
]
Test Date I Test Location I L
Soil
Type Test of
I Elevation
or Depth
. infeet)
Moisture (%) J Dry Density (pcf) Relative Compaction (%)
Comments . Field . Optimun I . Field . Maximum . Obtained . Required
957 N 1/5/2015 PA-3 Lot 80 5 CF 139.0 15.2% 11.0% 114.9 124.5 92% 90%
958 N 1/6/2015 PA-6 Lot 206 9 CF 148.0 13.4% 10% 1155 127.5 91% 90%
959 N 1/6/2015 PA-6 Lot 207 5 CF 147.0 15.4% 11.0% 13.7 - 124.5 91% 90%
965 N 1/6/2015 PA4 _11 CF 123.0 16.4% 12.5% 1130 122.0 93% 90%
971 N 1/6/2015 PA-6 Lot 247 _5 - CF 127.0 11.2% 11.0% 114.6 124.5 92% 90%
972 N 1/6/2015 PA-6 Lot 21l 5 CF 130.0 12.1% 11.0% 15.1 - 124.5 92% 90%
973 N 1/6/2015 PA-3 Lot 102 8 CF 1 143.0 17.6% 1 14.5%1 109.3 115.5 1 95% 90%
974 N 1/6/2015 PA-3 Lot l0l 8 CF 1 144.0 17.9% 14.5% 108.4 115.5 94% 90%
984 N 1/7/2015 PA-6 Lot 211 4 CF 136.0 16.3% 11.0% 112.7 123.5 91% 90%
995 N 1/8/2015 PA-3 Lot 102 1 CF 145.0 18.4% 16.0% 106.5 117.5 91% 90%
998 N 1/8/2015 PA-3 Lot 90 8 CF 144.0 17.5% 14.5% 107.4 115.5 93% 90%
999 N 1/8/2015 PA-3 Lot 91 8 CF 145.0 18.1% 14.5% 106.9 115.5 93% 90%
1003 N 1/9/2015 PA-3 Lot 113 5 CF 123.0 14.2% 11.0% 12.7 - 124.5 91% 90%
1018 N 1/15/2015 PA-6 Lot 206 - - CF 150.0 14.7% 1 11.0% 14.0 - 1 124.5 92% 90%
1019 1/15/2015 PA-6 Lot 207 - - CF 148.0 9.0% 10% 16.7 - 127.5 92% 90%
1020 1/15/2015 PA-6 Lot 208 - - CF 145.0 15.6% 11.0% 16.5 - 124.5 94% 90%
1021 1/15/2015
PM
PA-6 Lot 209 11 CF 143.0 15.8% 12.5% 10.7 - 122.0 91% 90%
1022 1/15/2015 PA-6 Lot 210 11 CF 141.0 17.4% 12.5% 10.0 - 122.0 90% 90%
1023 1/15/2015 PA-6 Lot 211 11 CF 139.0 15.6% 12.5% 12.1 - 122.0 92% 90%
1042 1/16/2015 Roberston Rd Sta. 26+05 4 - - CF 128.0 13.8% 11.0% 12.8 - 123.5 91% 90%
1061 N 1/19/2015 PA-6 Lot 211 . - CF 139.5 14.5% 1 11.0% 13.5 - 1 124.5 91% 90%
1062 N 1/19/2015 PA-6 Lot 210 5 - - CF 1 142.0 14.4% 11.0% 14.6 - 124.5 92% 90%
1063 N 1/19/2015 PA-6 Lot 209 - - CF 144.0 13.2% 11.0% 14.2 - 124.5 92% 90%
1064 N 1/19/2015 PA-6 Lot 208 5 CF 146.0 13.5% 11.0% 12.2 - 124.5 90% 90%
1065 N 1/19/2015 PA-6 Lot 207 - - CF 149.0 14.3% 11.0% 130 - 124.5 91% 90%
1066 N 1/19/2015 PA-6 Lot 206 - - CF 151.0 13.3% 11.0% 139 - 124.5 91% 90%
1088 N 1/20/2015 PA-3 Lot 101 - - CF 146.0 14.3% 10.5% 18.7 - 127.5 93% 90%
1089 N 1/20/2015 PA-3 Lot 113 - - CF 138.0 15.0% 1 10.5% 17.8 - 127.5 92% 90%
1096 N 1/21/2015 PA-3 Lot 114 ii 1 CF 136.0 13.4% 12.5% 110.3 122.0 90% 90%
1126 N 1/23/2015 PA-3 Lot 91 11 CF 145.0 16.1% 12.5% 110.4 122.0 90% 90%
1127 N 1/23/2015 PA-3 Lot 90 5 CF 147.0 14.2% 11.0% 113.5 124.5 91% 90%
1128 N 1/23/2015 PA-3 Lot 89 5 CF 149.0 14.7% 11.0% 112.9 124.5 1 91% 90%
1161 N 1/26/2015 PA-6 Lot 206 11 FG 0.0 14.2% 12.5% 110.4 122.0 90% 90%
1162 N 1/26/2015 A-6 Lot 207 5 FG 0.0 12.8% 11.0% 114.5 124.5 92% 1 90%
1163 N 1/26/2015 A-6 Lot 208 11 FG 0.0 12.9% 1 12.5% 110.8 122.0 91% 90%
1164 N 1/26/2015 A-6 Lot 209 5 FG 0.0 10.1% 11.0% 113.1 124.5 91% 90%
1165 N 1/26/2015 PA-6 Lot 210 9 FG 0.0 14.7% 10.5% 116.3 127.5 91% 90%
1170 N 1/27/2015 A-3 Lot 88 11_ CF 149.0 12.4% 12.5% 09.9 - 122.0 90% 90%
1234 N 1/30/2015 A-6 Lot 211 5 FG 0.0 12.1% 11.0% 13.1 - 117.0 97% 90%
1318 N 2/10/2015 A-3 Lot 103 5_ CF 142.0 13.7% 11.0% 13.7 - 124.5 91% 90%
1319 N 2/10/2015 A-3 Lot 104 5 CF 143.0 14.1% 11.0% 13.9 - 124.5 1 91% 90%
1320 N 2/10/2015 PA-3 Lot 113 5_ CF 140.0 13.3% 11.0% 16.5 - 124.5 94% 90%
1331 N 2/10/2015 A-3 Lot 114 4 CF 138.0 14.1% 11.0% 114.9 123.5 93% 90%
1333 N 2/10/2015 A-3 Lot 112 4 CF 140.0 14.4% 11.0% 113.9 123.5 92% 90%
1340 N 2/11/2015 A-3 Lot 78 11 CF 159.0 15.2% 12.5% 111.1 122.0 91% 90%
1341 N 2/11/2015 A-3 Lot 77 11 CF 161.0 15.0% 12.5% 10.5 122.0 91% 90%
1342 N 2/11/2015 A-3 Lot 79 4 CF 158.0 14.6% 11.0% 115.8 123.5 94% 90%
1343 N 2/11/2015 A-3 Lot 80 4 CF 157.0 14.5% 11.0% 112.6 123.5 1 91% 90%
1472 N 2/20/2015 A-3 Lot 112 . . 4 FG 0.0 11.4% 11.0% 114.4 123.5 93% 90%
1473 N 2/20/2015 A-3 Lot 113 5 FG 0.0 13.1% 11.0% 113.0 124.5 91% 90%
1474 N 2/20/2015 A-3 Lot 114 9 FG 0.0 14.1% 10.5% 117.2 127.5 92% 90%
1576 N 2/26/2015 A-3 Lot 100 9 FG 0.0 . 11.4% 10.5% 116.7 127.5 92% 90%
1577 N 2/26/2015 A-3 Lot lol 9 FG 0.0 1 10.1% 10.5% 1 117.7 127.5 92% 90%
1578 N 2/26/2015 A-3 Lot 102 9 FG 0.0 12.6% 10.5% 118.2 127.5 93% 90%
1579 N 2/26/2015 A-3 Lot 103 9 FG 0.0 9.3% 10.5% 118.0 127.5 93% 90%
1580 N 2/26/2015 A-3 Lot 104 9 FG 0.0. 11.6% 10.5% 114.8 127.5 90% 90%
1584 N 2/26/2015 A-3 Lot 80 5 FG 0.0 14.3% 11.0% 14.7 124.5 92% 90%
1585 N 2/26/2015 A-3 Lot 79 5 FG 0.0 12.6% 11.0% 112.1 124.5 90%
- -
8111/2015
- .
,-
..
Page 4of5
LGC Valley, Inc.
2420 Grand Avenue, Suite F2, Vista, California 92081
760-599-7000 I Fax 760-599-7007
REPORT OF COMPACTION TEST DATA
August 10, 2015
133023-03
Toll Brothers -
Robinson Ranch (PA3&6 Model Lots, PA-4, and PA-13)
Carlsbad, CA
=
Test #
Nuclear
Gauge (N),
or Sand Test Date
1 I Test Location
.1 Soil
Type Test of i ObtainedCone(S)
Elevation
or Depth
'in feet'
Moisture (%) Dry Density (pd)
Comments . Field Optimuni I . Field . Maximum
Relative Co"
Rege'd
1586 N 2/26/2015 PA-3 Lot 78 5 FG 0.0 12.5% 11.0% 115.0 124.5 92% 90%
1587 N 2/26/2015 PA-3 Lot 77 5 FG 0.0 10.9% 11.0% 115.9 124.5 93% 90%
1588 N 2126/2015 PA-3 Lot 81 5 FG 0.0 11.7% 11.0% 114.4 124.5 92% 90%
1592 N 2126/2015 PA-3 Lot 111 - - FG 0.0 11.5% 11.0% 1121 124.5 90% 90%
1593 N 2/26/2015 PA-3 Lot 112 5 FG 0.0 13.0% 11.0% 112.7 124.5 91% 90%
1594 N 2126/2015 PA-3 Lot 113 5 FG 0.0 13.2% 11.0% 118.0 124.5 95% 90%
1595 N 2/26/2015 PA-3 Lot 114 5 FG 0.0 11.4% 1 11.0% 114.5 124.5 92% 90%
1711 N 3/16/2015 PA-3 Lot 88 13 FG 0.0 11.0% 11.0% 117.9 125.5 94% 90%
1712 N 3/16/2015 PA-3 Lot 89 13 FG 0.0 11.9% 11.0% 117.6 125.5 94% 90%
1713 N 3/16/2015 PA-3 Lot 90 13 FG 0.0 10.5% 11.0% 115.9 125.5 92% 90%
1714 N 3/16/2015 PA-3 Lot 91 13 FG 0.0 11.6% 11.0% 117.5 125.5 94% 90%
2136 N 5/1/2015 PA-4 5 CF 127.0 11.0% 11.0% 113.0 124.5 91% 90%
2137 N 5/1/2015 PA-4 13 CF 128.0 12.7% 11.0% 1 113.8 125.5 91% 90%
2138 N 5/1/2015 PA-4 13 CF 127.0 12.9% 11.0% 114.0 125.5 91% 90%
2139 N 5/1/2015 PA-4 11 CF 125.0 13.1% 12.5% 112.9 122.0 93% 90%
Materiau: S=Soil, AC=Asphait Concrete, ATB = Asphalt Treated Base, AB = Aggregate Base, STS = Cement Treated Soil,
LTS = Lime Treated Soil, 0 = Other
Test of: CF = Compacted Fill, FG = Finish Grade, SF = Slope Face, N = Native Soil, U = Utility Trench, W = Wall Backfill,
SC = Sidewalk, Curb, Gutter, 0 = Other
KEY: FSG = Finish SubGrade, FS = Finish Surface, FBG = Finish BaseGrade, BOF = Bottom of Footing, TOW= Top of Wall
N = Nuclear Gauge, S = Sand Cone
Notes:
Tests were performed by a nuclear density gauge in accordance with the ASTM D2922 method or Sand Cone Method (ASTM 0 1556). The maximum dry density
and optimum moisture data was tested in accordance with the ASTM D1557 test method (Modified Proctor).
The field density test results represent the moisture content and density only at the depths and locations reported.
No guarantee or warranty of the contractor's work is made or implied.
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I2O15 Page 5 of 5
I Print Date:
Project No.
Client.
I Project Name:
Location:
Reviewed by:
I
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760-590-7000
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Robensoa Ranch IVest WI/age
PlannAig 4rea Models & Pack
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LGC Valley, Inc.
220613n4n,, &/2
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