HomeMy WebLinkAboutCDP 12-03; MAGNOLIA AVENUE RESIDENCE 3; GEOTECHNICAL INVESTIGATION AND FOUNDATION DESIGN RECOMMENDATIONS; 2012-03-21S 2r 12 •o
GS 5333 Missiop'Centei Roa'd, Suite 390
- NEW POINTE COMMUNITIES, INC March 21, 2012
16880 West Bemardo Drive, Suite 230 P/W 1201-02
-
San Diego,CA 92127 5 Report No. 120102-B-2
Attention: Mr. Scot Sandstrom
- -: Subject: Geotechnical Investigation and Foundation Design Reconimefldations for 5
Proposed Single-Family Residences, Parcel 2 and 3,1369 Magnolia Avenue,
Carlsbad, California
Gentlemen:
In accordance with your request, presented herein are the results of Advanced Geotechnical Solutions,
Inc 's (AGS) geotechmcal investigation and foundation design recommendations for the two proposed
- single-family residences at 1369 Magnolia Avenue, Carlsbad, California
The recommendations presented m the following report are based on a limited subsurface investigation
- performed by AGS, review of the referenced geotechnical investigation report prepared by Construction
and Testing Engineers, Inc (CTE) and associated laboratory testing It is AGS's opinion, from a
geotechmcal standpoint, the subject site is suitable for construction of the proposed residences, provided
- the recommendations presented in this report are mcorporated into the design, planning and construction
phases of site development Included in this report are 1) engineenng characteristics of the onsite soils,
2) unsuitable soil removal recommendations, 3) grading recommendations, 4) foundation design
- r'ecommendations, and 5) flatwork recommendations
Advanced Geotechnical Solutions, Inc., appreciates the opportunity to provide you with geotechnical
- ' consulting services and professional opinions. If you have, any questions, please contact the undersigned
at (619) 7084649.
Repectfully:Submitted;' S S
- Athanced Geotechnical Solutions, -
LU t4o. 2314 03 NO. 253 6130113' -ERTI'FIED C/)
GEOL
cm
- JEFFREY A CHANEY, Vice Presi~oF
/df
PAUL J. DERISI, Vice President' I
RCE 46544/GE 2314, Reg. Exp. 6-30-13 CEG 2536, Reg. Exp. 5-31-13
- - Distribution: '(5) Addressee
Attachments: Figure 1 - Site Location Map
- Figure 2— Geologiá Map and Site Exploration Plan;
Appendix A - Field and Laboi'atory Data;
Appendix B - General EarthvpicSpecifications &Qrading Guidelines;
Appendix C - Homeowner Màiiitenance Recommendations
ORANGE AND L.A. COUNTIES INLAND EMPIRE SAN DIEGO AND IMPERIAL COUNTIES
-
S (714)786-5661 (619)7O8-1649 (619)850-3980
- -'•
'
S ';
- GEOTECHNICAL INVESTIGATIONANI) FOUNDATION DESIGN
RECOMMENDATIONS FOR PROPOSED SINGLE-FAMILYRESIDENCES,
PARCELS 2 AND 3,1369 MAGNOLIA A VENUE, CARLSBAD, CALIFORNIA
March'21., 2012 Page 1
P/W12O1-02 Report No. 120.1-02-8-1.
1.0 SCOPE. OF SERVICES
This study is aimed at providing geotechnical information as it relates to 1) existing site4s0i1 conditions,
2) discussion of the geologic units onsite, 3) seismic hazard analysis, 4) engineering characteristics of the
,onsite soils, 5) excavation characteristics of earth materials, 6) seismic design parameters for use in the
structural design of the proposed single family residence, and 7) foundation design parameters for the
proposed conventional shallow foundation systçm.
The scope of our study included the following tasks
> Review of pertinent published and unpublished geologic and geotechnical literature, maps, and
aerial photographs. .
> Excavating and logging two (2) shallow hand auger brings'(Appendix A).
>..' Conducting a geotechnical engineering and geologic hazard analysis of the site.
Conducting a limited seismicity analysis
Determine 'design parameters of onsite soils' as a,, foundation medium including bearing and
friction values for foundation soils.
Dtermine the site-specific seismic design parameters for use in the structural design
> Preparation of a geotechnical foundation investigation report with exhibits summarizing our
findings. This report would be suitable for design, cóntractôr bidding,. and regulatory review.
GEOTECHNICAL STUDY LIMITATIONS
The conclusions and recommendations in this report are professional opinions based on our review of the
previously condUcted geotechnical investigation (CTE; 2007), associated lab testing, and the data
developed during this investigation.
The materials immediately adjacent to or beneath those observed may have different characteristics than
those observed No representations are made as to the quality or extent of materials not observed Any
evalUation regarding the presence or absence of hazardous material is beyond the scope of this firm's 13
services.-
3.0 ' . SITE LOCATION AN'D:DESCRIPTION"
The subject site' is located at .1369 Magnolia Avenue, Carlsbad, California (see Figure 1). The site is
bounded to the north by Magnolia Avenue, and to the east, west, and south by existing residential
properties The roughly rectangular-shaped site is approximately 330 feet long and 140 feet wide,
encompassing approximately Q.82 acre The overall site is sub-divided into three parcels Parcel 1, located
in the northern-portion of the site adjacent to Mágnolia Avenue, is currently occupied by an existing
singk-farnily residence.
Site topography is relatively flat to gently slo ping to the west Current elevations at the site range from
approximately 160 msl along the easterly property boundary 'to 151 feet msl at the westerly property
ADVANCED GEOTECHNICAL SOUJUONS,.. INC.
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boundary. The site contains scattered mature trees and is covered with a light growth of seasonal grasses
and weeds. Localized trash and construction debris were also observed on site.
4.0 PROPOSED DEVELOPMENT
As we understand the proposed development, parcels 2 and 3 will be graded to create relatively flat
building pads which will support the proposed single-family residences and associated improvements
The parcels are currently designed with cuts and fills on the order of 3 to 4 feet..The proposed residential
structures will be approximately 3,000 square feet, two-stories in height, wood-framed, and supported by
a conventional shallow slab-on-grade foundation system The structures will be surrounded by associated
flatwork and landscaping A pnvate driveway is planned along the westerly property line to provide
access to the new residences. A four to six foot high. retaining wall .will also be• constructed alOng the
westerly property line to support the proposed driveway and a freestanding sound wall.
5.0 FIELD AND LABORATORY INVESTIGATION
5.1. Field Investigation
Previously, CTE (2007) conducted a subsurface investigation to evaluate the onsite soil and
bedrock conditions. Six (6) test pits were excavated and logged to depths of six (6) feet below
existing grades. Bulk soil samples were collected from the exploratory test pits for laboratory
- testing Logs of CTE's test pits and results of the. associated laboratory testing are presented in
Appendix A.
In addition, AGSconducted a limited subsurface exploration at the subject on March 16, 2012.
Two hand auger borings were excavated at the subject site. The approximate locations of the
borings are shown On Figure 2. The excavations were.advanced to a maximum depth of 3.5 feet
- . below existing grades.
6.0. ,. ENGINEERING GEOLOGY
I -
.6.1. Geologic and Geomorphic Setting
The subject site is situated within the Peninsular Ranges Geomorphic Province The Peninsular
L . Ranges province occupies.the southwestern portion of California and extends southward to the
southern. tip of Baja Caifornia. In general the province consists of young, steeply sloped,
northwest trending mountain ranges underlain by metamorphosed Late Jurassic to Early
Cretaceous-aged; extrusive volcanic, rock and Cretaceous-aged igneous plutonic rock . of the
Peninsular Ranges Batholith. The westernmost' portion of the province is predominantly
underlain by younger marine and non-marine sedimentary rocks. The Peninsular Ranges'
dominant structural feature is northwest-southeast trending crustal blocks bounded by active
faults of the San Andreas transform system.
- .
. 6.2. Subsurface Conditions
A brief description of the earth materials encountered on this site is presented in the following
- sections. More detailed descriptions of these materials are provided in the hand auger logs
included in Appendix A. Based on our site reconnaissance, subsurface excavations, and review of
ADVANCED GEOTECHNICAL.. SOLUTIONS, INC.
March 21,2012 Page
P1W 1201-02 RepoitNo. 1201-02-B-2
the.,referenced geotechmcal investigation and geologic maps, the site is underlain to the depths
explored by old paralic deposits (marine terrace deposits) which are locally overlain by a thin
- veneer of topsoil/residual soils (undifferentiated) Although not encountered during our site
exploration, localized undocumented fill soils were observed dunng CTE's investigation (2007)
- and may be present at the site.
6.2 4. Topsoil/Residual Soil (undifferentiated)
Undifferentiated topsoil/residual soils were encountered in both onsite excavations and observed
to overlie the old paralic deposits These soils were of variable thickness, ranging from
approximately 3 0 feet in boring HA-1 to -.2.5 feet in HA-2 As encountered, these materials
generally consisted of light gray brown to reddish brown, moist, loose to medium dense, silty to
clayey fine- to medium-grained sand.
- 6.2.2. Old :Paralic Deposits, Units 24
The site is underlain to maximum depth explored by Old Paralic Deposits, Units 2-4 These
materials can generally be described as mottled gray brown to reddish brown, slightly moist to
moist, medium dense to dense, silty fine to medium. grained sand.
63. Groundwater
-
Groundwater was not encountered in our exploratory excavations. No natural groundwater
condition is known to exist at the site that would impact the proposed site development However,
it should be noted that localized perched groundwater may develop at a later date, most likely at
or near fill/bedrock contacts, due to fluctuations in precipitation, imgation practices, or factors
not evident at the time of our field explorations.
6.4. Non-seismic Geologic hazards
64.1. Mass Wasting
No evidence of mass wasting was observed onsite nor was any noted on the reviewed maps.
-.
6.4.2. Flooding
According to available FEMA maps, the site is not in 'a FEMA identified flood hazard area
6.43. Subsidence/Ground Fissuring
Due to the presence of the dense underlying materials, the potential for subsidence and ground
fissuring due to settlement is unlikely.
6.5. Seismic Hazards
-
The site is located in the tectonically active Southern California area, and will therefore likely
experience shaking effects from earthquakes The type and seventy of seismic hazards affecting
the site are to a large degree dependent upon the distance to the causative fault, the intensity of
- the seismic event, and the underlying soil characteristics. The seismic hazard may be primary,
such as surface rupture and/or ground shaking, or secondary, such as liquefaction or dynamic
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- March 21,2012 Page 4
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- settlement The following is ,a site-specific discussion of ground motion parameters, earthquake-
induced landslide hazards, settlement, and liquefaction The purpose of this analysis is to identify
potential seismic hazards and propose mitigations, if, necessary, to reduce the hazard to an
acceptable level of risk The following seismic hazards discussion is guided by theCalifomia
Building Code (2010), CDMG (2008), and Martin and Lew (1 998)
- 6.5;4. Surface Fault Rupture :
- No known active faults have been mapped at or near the subject site The nearest known active
surface fault is the Oceanside section of the Newport-Inglewood-Rose Canyon fault zone which
- is approximately .5 ,miles west of the subject site Accordingly, the potential for fault surface
- rupture on the subject site is low. This conclusion is based on literature review and aerial
photographic analysis.
6.5.2. Seismicity
-
As noted, the site is within the tectonically active southern California area, and is approximately 5
miles from an active fault, the Oceanside section of the Newport-Inglewood-Rose Canyon fault
- zone The potential exists for strong ground motion that may affect future improvements
- At this point in time, non-critical structures (commercial, residential, 7and. industrial) are usually
- designed according to the California Building Code (2010) and that of the controlling local
agency.. However, liquefaction/seismic lope ábility. analyses, critical structures, water tanks
- and unusual structural designs will likelyrequire site pecificgrouridmotioñ input.
63.3. Liquefaction
- Due to the.dense nature of the. underlying materialsand lack of a shallow groundwater table at the
project site, the potential for seismicallyinduced liquefaction is considered negligible.
6.5.4. Dynamic Settlement
Dynamic settlement occurs in response to an earthquake event in loose sandy earth materials
This potential of dynamic settlement at the subjectsite is considered remote due to the presence
of shallow marine terrace/bedrock and-the absence of loose, sandy soils.
- 6.5.5. Seismically lEnduced Landshding
- Evidence of landsliding at the site was not observed during our field explorations nor was any
geomorphic features indicative of landsliding noted during our review of aerial photos and
- • published geologic maps. S
-
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P/W 1201-02 Report No. 1201-02-B-2
- 7.1.6. Chemical/Resistivity Test Results
Preliminary soluble sulfate and chloride, and resistivity testing has not been conducted by AGS
- but was performed by C1'E during their 2007 geotechnical investigation. Based upon the results
of their testing and our previous experience in the area it is anticipated that the onsite soil will
exhibit "negligible" sulfate concentrations when classified in accordance with AC! 318-05 Table
- 4.3.1 (per 2010 CBC) and are anticipated to be "mildly" corrosive to metals. Consultation with a
-
corrosion engineer is recommended. Final determination of actual chemical/resistivity design
parameters for the foundation will be determined at the conclusion of the grading and will be
- presented in the grading report.
7.1.7. Earthwork Adjustments
- It is anticipated that the onsite fill/residual soils will shrink on the order of 4 to 6 percent when re-
compacted. The paralic deposits are anticipated to bulk on the order of 5 to 10 percent when used
to make compacted fill.
- 7.1.8. Pavement Support Characteristics
It is anticipated that the onsite soils will have good to moderate support characteristics.
Depending upon the final distribution of site soils, pavement support characteristics could vary.
If structural pavements are to be constructed (concrete or asphaltic concrete), an "R"-value of 35
- can be utilized for the preliminary design of pavements. Final design should be based upon
representative sampling of the as-graded soils.
- 8.0 CONCLUSIONS AND RECOMMENDATIONS
Construction of the proposed residential structure and associated improvements is considered feasible,
from a geotechriical standpoint, provided that the conclusions and recommendations presented herein are
- incorporated into the design and construction of the project. Presented below are specific issues identified
by this study as possibly affecting site development. Recommendations to mitigate these issues are
presented in the text of this report.
8.1. Grading Recommendations
8.1.1. Unsuitable Soil Removals
In areas to receive settlement sensitive structures, all topsoil/residual soil, highly weathered
formational materials, and any undocumented fill soils. It is anticipated that the upper 3 to 4 feet
- of the onsite soils will require removal and recompaction for the support of settlement sensitive
structures. Localized areas may require deeper removals. Minimally the removals should extend a
lateral distance of at least 5 feet beyond the limits of settlement sensitive structures. If deeper
removals are performed, the removals should extend a lateral distance equal to the depth of
removal beyond the improvement limits. Removal bottoms should expose competent formational
-
materials in a firm and unyielding condition. The resulting removal bottoms should be observed
by a representative of AGS to verify that adequate removal of unsuitable materials have been
- ADVANCED G[01ECHNICAL SOLUTIONS, INC.
March 21, 2012 Page 7
P1W 1201-02 Report No. 1201-02-B-2
conducted prior to fill placement. In general, soils removed during remedial grading will be.
suitable for reuse in compacted fills, provided they are properly moisture conditioned and do not
contain deleterious materials. . Grading shall be accomplished under the observation and testing of
the project soils engineer and engineering geologist or their authorized representative in
accordance with the recommendations contained herein, the current grading ordinance of the City
of Carlsbad.
8.1.2. Earthwork Considerations
8.1.2.1. Compaction Standards
- Fill and processed natural ground shall be compacted to a minimum relative compaction
of 90 percent, as determined by ASTM Test Method: D 1557. Compaction shall be
achieved at or slightly above the optimum moisture content and as generally discussed in
- the attached Earthwork Specifications (Appendix B).
- 8.1.2.2. Treatment of Removal Bottoms
- At the completion of unsuitable soil removals, the exposed bottom should be scarified to
- a minimum depth of eight inches, moisture conditioned to above optimum moisture and
compacted in-place to the standards set forth in this report.
8.1.2.3. Fill Placement
Fill should be placed in thin lifts (eight-inch bulk), moisture conditioned to at or slightly
above the optimum moisture content, uniformly mixed, and compacted by the use of
both wheel rolling and kneading type (sheeps foot) compaction equipment until the
designed grades are achieved.
8.1.3. Cut Fill Transition Lots
Where design grades and/or remedial grading activities create a cut/fill transition, the cut and
shallow fill portions of the building pad shall be overexcavated a minimum depth of three feet or
18 inches below the bottom of the proposed footings (whichever is deeper) and replaced with
compacted fill. These remedial grading measures are recommended in order to minimize the
potential for differential settlements between cut and fill areas. The undercut should be graded
such that a gradient of at least one percent is maintained toward deeper fill areas or the front of
the lot.
8.2. Design Recommendations
It is our understanding that the proposed foundations will consist of a shallow slab-on-grade
foundation systems supporting the proposed two-story wood-frame residential structures. It is our
further understanding that the foundation system will be conventionally reinforced with steel
reinforcing bars. Design recommendations are provided herein. In addition to the structure,
associated driveways, hardscape and landscape areas are proposed. From a geotechnical
perspective these proposed improvements are feasible provided that the following
recommendations are incorporated into the design and construction.
ADVANCED GEOTECHNICAL SOL.IJDONS, INC.
March 21" 2012
P1W 1201-02
Page
Report No. 1201-4k-B-2
8.2.1. Foundation Design Criteria
The single-family residential structure can be supported on conventional shallow foundations and
slab-on-grade systems The expansion potential of the underlying soils is classified as "Low"
The following values may be used in the foundation design.
Allowable Beanng: 2000,.Ibs./sq.ft.
Lateral Bearing: 250 lbsJq.ft. at a depth of 12 inches plus
125 Ibsilsqft. for each additional 12 inches
embedment to amaximum of 2000 lbs./sq.ft.
Sliding Coefficient: 0.35
Settlement: Total = 3/4 inch
Differential: 3/8 inch in 20 fret
The above values may be increased as allowed by Code to resist transient loads such ás.wind or
seismic. Building Code and structural design considerations may govern.. Depth and
reinforcement requirements should be evaluated by the Structural Engineer.
8.2.2. Seismic Design Parameters
The following seismic design parameters are presented to be code compliant to the California
'Building Code (2010). The subject lots have been identified to be sit class "D" in accordance
witlrCBC, 2010, Table 1613.5.3(1). The lots are located at Latitude 33.15682 N and, Longitude
117;332,52* W Utilizing this information, the computer program USGS Earthquake Ground
Motion Parameters Version 5.1.0 and' ASCE 7 criterion, the seismic design category. for 0.20
seconds (Sc) and LO second (Si) period response accelerations can be determined (CBC, 2010
1613.5.5.1) along with the design spectral reponsë acceleration (CBC, 2010 1613.5.4).
Seismic Design Criteria
Mapped Spectral Acceleration (0.2 sec Period), Ss • 1.275g
Mapped Spectral Acceleration (1.0 sec Period), S 0.480g
Site Coefficient, F8 1.0
Site Coefficient, F,, . 1.52
MCE Spectral Response Acceleration (02 sec Period), SMs 1.275g
MCE Spectral Response Acceleration (1.0 sec'Period), SM1 0.730g
Design Spectral ResponseAcceleration (0.2sec Period), SDs 0.850g
Design Spectral Response Acceleration (1.0 sec Period), SDI 0.487g
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8.2.3. Foundation Design
- 8.2.3.1. Conventional Foundations
Based upon the onsite soil conditions and information supplied by the 2010 CBC,
-
conventional foundation systems should be designed in accordance with Section 8.2.1
and the following recommendations.
> Interior and exterior footings for the proposed two-story residence should be a
- minimum of 15 inches wide and extend to a depth of at least 18 inches below lowest
adjacent grade. Footing reinforcement should minimally consist of four No. 4
reinforcing bars, two top and two bottom or two No. 5 reinforcing bars, one top and
one bottom.
Conventional, slab-on-grade floors, underlain by "low" expansive soil, should be five
or more inches thick and be reinforced with No. 3 or larger reinforcing bars spaced
18 inches on center each way. The slab reinforcement and expansion joint spacing
should be designed by the Structural Engineer.
> if exterior footings adjacent to drainage swales are to exist within five feet
horizontally of the swale, the footing should be embedded • sufficiently to assure
embedment below the swale bottom is maintained. Footings adjacent to slopes
should be embedded such that a least seven feet are provided horizontally from edge
of the footing to the face of the slope.
> Isolated spread footings outside the footprint of the proposed structures should be
tied with grade beams to the structure in two orthogonal directions.
A grade beam reinforced continuously with the garage footings shall be constructed
across the garage entrance, tying together the ends of the perimeter footings and
between individual spread footings. This grade beam should be embedded at the
same depth as the adjacent perimeter footings. A thickened slab, separated by a cold
joint from the garage beam, should be provided at the garage entrance. Minimum
dimensions of the thickened edge shall be six (6) inches deep. Footing depth, width
and reinforcement should be the same as the structure. Slab thickness, reinforcement
and under-slab treatment should be the same as the structure.
- 8.2.4. Under Slab
Prior to concrete placement the subgrade soils should be moisture conditioned to optimum
moisture content.
- A moisture and vapor retarding system should be placed below the slabs-on-grade in portions of
- the structure considered to be moisture sensitive. The retarder should be of suitable composition,
-
thickness, strength and low permeance to effectively prevent the migration of water and reduce
the transmission of water vapor to acceptable levels. Historically, a 10-mil plastic membrane,
- such as Visqueen, placed between one to four inches of clean sand, has been used for this
- purpose. More recently Stego® Wrap or similar underlayments have been used to lower
permeance to effectively prevent the migration of water and reduce the transmission of water
- ADVANCED GEOTECHNICAE. SOLUTIONS, INC.
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P44201-02 Report No:1201-02-13-2
vapor to acceptable levels The use of this system or other systems, matenals or techniques can be
considered, at the discretion of the designer, provided the system reduces the vapor transmission
- rates to acceptable levels
-
'8.2.5. Deepened Footings ^And Structural Setbcks
It is generally recognized that improvements constructed in proximity to natural slopes or
properly constructed, manufactured slopes can, over a period of time, be affected by natural
- processes including gravity forces, weathering of surficial soils and long-term (secondary)
settlement Most building codes, includiriji the California Building Code (CBC), require that
structures be set back or footings deepened, where subject to the influence of these natural
- processes
For the subject site, where foundations for residential structures are to exist in proximity to
-
slopes, the footings should be embedded to satist' the requirements presented in Figure 3
1 FIGURE 3
FACE OF FOOTING
TOP OF
SLOPE
FACE OF
STRUCTURE
T
NOT
BUT NE
CEEE
ED NOT
H
TOE OE OF SLOPE
H12\13UT NEED
EXCEED 15 FT. MAX.
,816. Concte Dealgn
- Our previous experience in the general area indicates onsite soils likely exhibit a "negligible"
sulfate exposure when classified in accordance with ACT 318-05 Table 4.3A (per 2010 CBC)
Final determination will be based upon testing of near surface soils obtained at the conclusion of
- grading However, some fertilizers have been known to leach sulfates into soils otherwise
containing: "negligible" sulfate concentrations and increase the sulfate concentrations to
potentially detrimental levels It is incumbent upon the owner to determine whether additional
- protective measures are warranted to mitigàtè the potential for. increased sulfate concentrations to
onsite soils as a result of the future homeowner's actions;
- ADVANCED (jEOTECHNICAL. SOLIJIIONS, INC
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P1W 1201-02 Report No. 1201-02-B-2
8.2.7. Corrosion
- Our previous experience in the general area indicates onsite soils likely are "mildly" corrosive to
buried metallic materials. AGS recommends minimally that the current standard of care be
employed for protection of metallic construction materials in contact with onsite soils or that
- consultation with an engineer specializing in corrosion to determine specifications for protection
of the construction materials. Final determination will be based upon testing of near surface soils
obtained at the conclusion of grading.
8.2.8. Retaining Walls
The following earth pressures are recommended for the design of retaining walls onsite:
Rankine Equivalent Fluid
Level Backfill Coefficients Pressure (psf/lin.ft.
- Coefficient of Active Pressure: K. = 0.31 38
Coefficient of Passive Pressure: K = 3.25 407
Coefficient of at Rest Pressure: K0 = 0.47 59
Rankine Equivalent Fluid
2: 1 Backfill Coefficients Pressure (nsf/lin.ft.1
Coefficient of Active Pressure: Ka = 0.47 59
Coefficient of Passive Pressure:
Descending K. (-) = 1.23 154
Coefficient of At Rest Pressure: K. = 0.72 90
The foundations for retaining walls of appurtenant structures structurally separated from the
building structure may bear on properly compacted fill. A bearing value of 2,000 psf may be
used for design of retaining walls. Retaining wall footings should be designed to resist the lateral
forces by passive soil resistance and/or base friction as recommended for foundation lateral
resistance. To relieve the potential for hydrostatic pressure wall backfill should consist of a free
draining backfill (sand equivalent "SE" >20) and a heel drain should be constructed. The heel
drain should be place at the heel of the wall and should consist of a 4-inch diameter perforated
pipe (SDR35 or SCHD 40) surrounded by 4 cubic feet of crushed rock (3/4-inch) per lineal foot,
wrapped in filter fabric (Mirafi® 140N orequivalent)
Proper drainage devices should be installed along the top of the wall backfill, which should be
properly sloped to prevent surface water ponding adjacent to the wall. In addition to the wall
drainage system, for building perimeter walls extending below the finished grade, the wall should
be waterproofed and/or damp-proofed to effectively seal the wall from moisture infiltration
through the wall section to the interior wall face.
The wall should be backfilled with granular soils placed in loose lifts no greater than 8-inches
thick, at or near optimum moisture content, and mechanically compacted to a minimum 90
percent relative compaction as determined by ASTM Test Method D1557. Flooding or jetting of
backfill materials generally do not result in the required degree and uniformity of compaction
- ADVANCED GEOTECHNICAL SOUJ11ONS, INC.
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and, therefore, is not recommended. The soilsengineer or his representative should observe the
-
retaining wall footings, backdrain installation and be present during placement of the wall backfill
to confirm that the walls are properly backfilled and compacted.
8.3. Utility Trench Excavation
All utility trenches should be shored or laid back in accordance with applicable OSHA standards.
Excavations in bedrock areas should be made in consideration of underlying geologic structure.
- AGS should be consulted on these issues during construction.
I 8.4. Utility Trench Backfill
- Mainline and lateral utility trench backfill should be compacted to at least 90 percent of
maximum dry density as determined by ASTM D 1557. Onsite soils will not be suitable for use
I as bedding material but will be suitable for use in backfill, provided oversized materials are
removed. No surcharge loads should be imposed above excavations. This includes spoil piles,
lumber, concrete trucks or other construction materials and equipment. Drainage above
excavations should be directed away from the banks. Care should be taken to avoid saturation of
I - the soils.
Compaction should be accomplished by mechanical means. Jetting of native soils will not be
- acceptable.
83. Exterior Slabs and Walkways
8.5.1. Subgrade Compaction
The subgrade below exterior slabs, sidewalks, driveways, patios, etc. should be compacted to a
- minimum of 90 percent relative compaction as determined by ASTM D 1557.
8.5.2. Subgrade Moisture
- The subgrade below exterior slabs, sidewalks, driveways, patios, etc. should be moisture
conditioned to a minimum of 110 percent of optimum moisture content prior to concrete
placement.
8.5.3. Slab Thickness
Concrete flatwork and driveways should be designed utilizing four-inch minimum thickness.
8.5.4. Control Joints
- Weakened plane joints should be installed on walkways at intervals of approximately eight to ten
feet. Exterior slabs should be designed to withstand shrinkage-of the concrete.
8.5.5. Flatwork Reinforcement
Consideration should be given to reinforcing any exterior flatwork.
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8.5.6. Thickened Edge
- Consideration should be given to construct a thickened edge (scoop footing) at the perimeter of
slabs and walkways adjacent to landscape areas to minimize moisture variation below these
improvements. The thickened edge (scoop footing) should extend approximately eight inches
- below concrete slabs and should be a minimum of six inches wide.
8.6. Plan Review
Once grading and foundation design plans become available, they should be reviewed by AGS to
verify that the design recommendations presented are consistent with the proposed construction.
- 8.7. Geotechnical Review
As is the case in any grading project, multiple working hypotheses are established utilizing the
-
available data, and the most probable model is used for the analysis. Information collected during
the grading and construction operations is intended to evaluate these hypotheses, and some of the
assumptions summarized herein may need to be changed as more information becomes available.
- Some modification of the grading and construction recommendations may become necessary,
should the conditions encountered in the field differ significantly than those hypothesized to exist.
AGS should review the pertinent plans and sections of the project specifications, to evaluate
- conformance with the intent of the recommendations contained in this report.
If the project description or final design varies from that described in this report, AGS must be
- consulted regarding the applicability of, and the necessity for, any revisions to the
recommendations presented herein. AGS accepts no liability for any 'use of its recommendations
if the project description or final design varies and AGS is not consulted regarding the changes.
9.0 SLOPE AND LOT MAINTENANCE
Maintenance of improvements is essential to the long-term performance of structures and slopes.
- Although the design and construction during mass grading is planned to create slopes that are both
grossly and surficially stable, certain factors are beyond the control of the soil engineer and geologist.
The homeowners must implement certain maintenance procedures.
The following recommendations should be implemented.
9.1. Slope Planting
Slope planting should consist of ground cover, shrubs and trees that possess deep, dense root
structures and require a minimum of irrigation. The resident should be advised of their
responsibility to maintain such planting.
9.2. Lot Drainage
- Roof, pad and lot drainage should be collected and directed away from structures and slopes and
toward approved disposal areas. Design fine-grade elevations should be maintained through the
life of the structure or if design fine grade elevations are altered, adequate area drains should be
installed in order to provide rapid discharge of water, away from structures and slopes. Residents
ADVANCED GEOTECHNICAL. SOLIJUONS, INC.
March 24) 2012 Page 14
P/Wi201-02 Report No. 1201,42-B-2
should be made aware that they are• responsible for, maintenance and cleaning of all drainage
ten-aces, down drains and other devices that have been installed to promote structure and slope
stability.
93 Slope Imation
The resident, homeowner and Homeowner Association should be advised of their responsibility
to maintain irrigation systems. Leaks should be repaired immediaiely. Sprinklers should be
adjusted to provide maximum uniform coverage With a minimum of water usage and overlap.
Overwatenng with consequent wasteful run-off and ground saturation should be avoided If
automatic sprinkler systems are installed, their use must be adjusted to account for natural rainfall
conditions.
.9.4. BurrowingAnimals
Residents 'or homeowners should undertake a program for the elimination of burrowing animals.
This should be an ongoing program in order to. maintain slope stability.
1.0.0 LIMITATIONS
This report is based. on the project as described and the information obtained from the referenced
geotechnical investigation report and the excavations at the approximate locations indicated on the Figure
2 The findings are based on the results of the field, laboratory, and office investigations combined with
an interpolation and extrapolation of conditions between and beyond the excavation locations. The
results reflect an interpretation of the direct evidence obtained Services performed by AGS have been
conducted in a manner consistent with that level of care and skill ordinarily exercised by members of the
profession currently practicing in the same locality under similar conditions No other representation,
either expressed or implied, and no warranty or guarantee is included or intended
The recommendations presented in this report are based on the assumption that an appropriate level of
field review will be provided by geotechnical engineers arid engineering geologists who are familiar with
the design and site geologic conditions That field review shall be sufficient to confirm that geotechnical
and: geologic conditions exposed during grading are consistent with the geologic representations and
corresponding recommendations presented in this report AGS should be notified of any pertinent
changes in the project plans or if subsurface conditions are found to vary from those described herein
Such changes or variations may require are-evaluation of the recommendations, contained in this report.
The data, opinions, and recommendations of this report. are, applicable to the specific design Of this project
as discussed in this report They have no applicability to any other project or to any other location, and
any and. all 'subsequent users accept any and all liability resulting from :any use, or reuse' of the data,
opinions, and recommendations without the, prior written Consent of AGS.
AGS has no responsibility *for construction means, methods, techniques, sequences, or procedures, or for
safety precautions or programs in connection with the construction, for the acts or omissions of the
CONTRACTOR, or any other person performing any of the construction, or for the failure of any of them
to carry out the construction in accordance with the final design drawings and specifications.
ADVANCED GEOTECHNICAL. SOLUTIONS, INC.
March 21, 2012 Page 15
P1W 1201-02 Report No. 1201-02-13-2
REFERENCES
- American Concrete Institute, 2002, Building Code Requirements for Structural Concrete (ACI318M-02)
and Commentary (ACI318R1vf-02), ACI International, Farmington Hills, Michigan.
- American Society for Testing and Materials (2008), Annual Book ofASTM Standards, Section 4,
Construction, Volume 04.08, Soil and Rock W. ASTM International, West Conshohocken,
Pennsylvania.
California Code of Regulation, Title 24,2010 California Building Code, 3 Volumes.
-
Construction Testing and Engineers, Inc., Preliminary Geotechnical Investigation, Proposed Three Lot
Residential Development, 1369 Magnolia Avenue, Carlsbad, California, dated April 3, 2007
(CTE Job No. 10-8791 G).
- Kennedy, M.P., Tan, S.S., et. al., 2007, Geologic Map of the Oceanside 30' x 60' Quadrangle, California,
California Geological Survey: Regional Geologic Map No. 2, scale 1:100,000.
ADVANCED GEOTECHNICAL. SOLIJHONS, INC.
N SITE LOCATION MAP
1369 MAGNOLIA AVENUE
CARLSBAD, CALIFORNIA
PIW12O1-02 FIGURE 1
SOURCE MAP - TOPOGRAPHIC MAP OF THE
SAN LUIS REY 7.5 MINUTE QUADRANGLE,
SAN DIEGO COUNTY, CALIFORNIA
GUflR I FXI.ST. RLnGJ
205-280-17
-- I NEW 6'W •- OD FUCE
N.A.P.
EXIST. BLDG
__- -
- - =
LWE FST SRUC1J c ax
- - - 4 - - 4R 1B UNE -REA -
LAJ
:IsflNG P COP 92' 125 SF NEr ARE4=iB M SF GROSS AREA= 14 551 SF PCL 1 FF=l7.O0 '- I NET AREA—l1 395 SF -
S(A9/96SSF I
'1 O i
AD= 756.50 00
TP-5
( NAP. l jj1 HL HA-1
PROUT
PALM UNrLkI 751 I i Qóp !
REOC4WD
- TP se I
14 DUMM
NEW6
O
205 05-280r-38 .2 6 80-67
VA 7'ç 2 —280— j: 5'SLVD WOOD n
/
TYPE A 15' LJT FACE WALL r 6 LJT FAX WALL
MN
WI ECC7TVE C4P I WI DEEO&AITVE
LEGEND
Approximate Location of Exploratory: Excavation,
HA-2 AGS, 2012
L GRAPHIC SCALE Approximate Location of Exploratory Trench, FIGURE 2
CTE 2007 TP-6 20' 10' 20' 40' 80' Geologic Map and
I Exploration Location Plan
Old Paralic Deposits (formerly mapped as Terrace
OOP
Depos its)' ( ADVANCED GEOTECHMCAL SOLIfflONS, INC.
( 5333 Mission Center Road, Suite 390
t / San Diego, California 92108 N.A.P. Not a Part of Report / Telephone: (619)708-1649 Fax: (714)09-3287
APPENDIX k
FIELD AND LABORATORY DATA
ADVANCED GEOTEC1INICAL SOLUTIONS, INC., 2012
I - CONSTRUCTION TESTING AND ENGINEERING, INC., 2007.
ADVANCED GEOTECIINICAL SOI.IJflONS, INC.
ADVANCED GEOTECHNICAL SOLUTIONS, INC.
LOG OF EXPLORATORY EXCAVATION
P1W NO.: 1201-02
- PROJECT NAME: 1369 Magnolia
CLIENT: New Pointe Comnunities
LOCATION: See Exioration Location Plan
LOGGED BY: PJD
EQUIPMENT: Hand Excavated
DATE: 3/1612012
- SAMPLES Laboratory Testing -
Hand Auger HA-1 ,
CL
W (I) E 2:-' 0
MATERIAL DESCRIPTION AND COMMENTS -
U'
Topsoil/Residual Soil (Undifferentiated)
• I
SC Light gray brown to brown, moist, loose, CLAYEY SAND with silt, fine-
•
HAl-I to medium grained El = 34
SM Light brown to red brown, moist, loose to medium dense, SILTY
SAND, fine- tomediumgrained;traceclay
-
OldParalicDeposits
SM Light gray brown to orangish brown, slightly moist, dense, SILTY
• SAND
Excavation Terminated at 3.5 Feet 5 No Groundwater Encountered
Backfilled with Soil Cuttings
10
15
0 Sample Type: ILSmallPIasticBag —Bt1kSample —water Table
LU
O Laboratory Testing: AL = Atterberg Limits El = Expansion Index MD = Maximum Density SA = Sieve Analysis
SR = Sulfate/Resistivity Test SH = Shear Testing RV = R-Value Test CO = Consolidation
ADVANCED GEOTECHNICAL SOLUTIONS, INC.
LOG OF EXPLORATORY EXCAVATION
P1W NO.: 1201-02 LOGGED BY: PJD
- PROJECT NAME: 1369 Magnolia EQLI1PMENT:Hand Excavated
CLIENT: New Pointe Comnvnities DATE: 3/16/2012
LOCATION: See Exioration Location Plan
- SAMPLES Laboratory Testing
CL E Hand Auger HA-2 C 12
0 E W °- E CO 0
MATERIAL DESCRIPTION AND COMMENTS U)
-
lopsoillResidual Soil (Undifferentiated)
SM Light gray brown to tight brown, slightly moist, loose to medium
dense, SILTY SAND, fine- to medium-grained; trace clay
Old Paralic Deposits
SM Light gray brown to orangish brown, slightly moist, dense, SILTY
SAND; weakly cemented
Excavation Terminated at 3.5 Feet
No Groundwater Encountered
Backfllled with Soil Cuttings
10
15
jSample Type: (L Small Plastic Bag - Bulk Sample ZZ —Water Table
ILI O Laboratory Testing, AL = Atterberg Limits El = Expansion Index MD = Maximum Density SA = Sieve Analysis
SR = Sulfate/Resistivity Test SH = Shear Testing RV = R-Value Test co = Consolidation
fl:U u1.
c - %CONSTRUCTION TESTING & ENGINEERING, IC
- ..' 0101CcHnl1, I-CCM RUCftOd ENOINKIRIMU.TfITINGANO IN3PfI IIl - - •iiii no, S IIIlfl I IftDOIIG. C PaIS HO 7I.4lSI-
PROJECT:' Three LoI1)evlupnieut FXCAVAI'OR D Higgcnbotharn
rir JOB NO: 10-87910 EXCAVATION METHOD: BACKHOE EXCAVATION DAII-: LO(J(DBY: J)K - -• SAMPLINC\ibTtfOD: J3LQK - LtvATION; - IS
TEST PIT LOG TP- I itc ;; Z)
. ..
T
DESCRIPTION
- .
ILI
) ,L / 0-I 1'01SD1LJose lo mediuni dense. IhUymi. - --
/ dark bruwi, silly SAND (SM) with iuusfoinics.
\.\ RV ('ILE ,L. ,c.J
/ 1-3 RESIDUAL 50)1 0 -
Medium dcne, slightly rnoisL- light hiown
- Qr. - to tan, silty Line SAND (SM)
3-6 OU.TERliARYTERRACt DLPOSflS(Q
i.)ene. slightly rnoist.-Iight browi
-
tt tun,-silty line
- - ra dcjlli 6 tbg . . • - No ground w;i rer
- -
. HaikfiLid wii) poih. -
-•:
0 •• . 0
- -10-
0
•
-15-
- - 0 - - -
iGUR1 -P-I:.
ç CONSTRUCTION TESTING & ENGINEERING, INC.
0? [CAI I COII1100C 01014 0140IWUAIII III hOG AND 1"501 MOM Il0O ___ to o4otIt 03C. Soul 111 i fOCal 0100. Cl 00000 1 lii ho 1.10
— 1'rtOIE(I: Three Lot Development EXCAVATOR: D. Fliggenhotham CIFUOB NO: 10-879tG EXCAVATION METtIOD: BACKI-EOE FXC'.\V.TION L).'Vfl iI(,a!(11): LOGCoED 131: DK 3ANIPLNUMETIlOD: BULK Lt. n\:ATlON: 132.5,
zi TEST PIT LOG TP2 LahormorvTosuN 41
DESCRIPTION — — — — —
— I 0-1.5' !QP—.sQEL-
Lciose to medium dense, dry to slightly moist. \-j twoi. silly Fine grained SAN01) (SM) with debris
— \ . - j and organic materials (roors, logs i.
1.5-3' RESIDUAl. SOIL
• —Ql Ivledium dense. slightly moist. Iiht brown
to Lan. silly tine SAND (SM). A -5- -
35•5 OUATERNAtY TERRAcEDEPOSn'S (QLL
— Total depth 5$ Dense, slightly moist. motticd orange brown - No groundwait'r to ran, silty fine SAND (SM).
-
-Je
Backfilled with spoil'
-IS .
W-2 —
Q!STRUCTION TESTING & E41,NEERING, INC. Iu, cct,i i I un inuc 110,. £ 0311111 flillfl TI ITIUO All., I0.11 CTIAI 11,111 I I Lsl0qr,00. CA 07311 III Ill
--
PIOItCT: Three Lot Dcvclupr F.).C.4vAlorc: I). 1-iiggciibotham . CTEJOR io 10-8791 EXCAVATION METHOD: BACK1OE FACAVATION DATE. LOC,CFDO\: LDK
— — - SAMPLING MFTHOD BUTJ<
- EL0.HO -.t57.I
TEST PIT LOG: TP-3 ik ukli\ Ie,h O U -
C &- 0
DESCRTPTTON
T T 0-I OPSOJI . Lose medium dense. ltI\' iuo. • . . 0
/ dark brown, silty SAND SM with .r.nu/oI-anic
- L3'
- Medium dense, slightly moist, light hi-own
to ran, silty fine SAND (SM).Qt
3-5' QUATERNAR=RkACE I)F20.3-ITS (Or):
Dense, slightly ninist. niottled orange LIEUiWIi
— Total depth S' 1bg to tan. shy fine SAND (SM). No ground water
— Buckflhled with spoils
— — - 0
F1cURl1 11-13
.
_____ • CONSTRUCTION TESTING & EN'GTNEERINGr INC. • ' 06 OT(000ICAIC C0Q I Soc io N £501 6t 610 0TUy,.c 4510 I liP( OIl 05 . 01111115 0640. 00,11.11) 1 I 05lCl0I. (117501 III 141 5)0 - ..
PROJECT: Thrce Lot Development EXCAVATOR:, D. J-liggenbotham CTF.JOb O: 1087913
-:- IXCAVATION METHOD: IIACK}IOP ENCVMIôrDATL 2/16/2W LOGGED BY: DX S SAtofPLtN(MEfl-IOD: BULK tLEVATK):
cf. 06
. , TEST PIT LOG TP-4 L tbl)I III 1\ T
0 0
.- DESCRIPTION • = =
- . L 0-75' LOPSOILo to niedkirnderise. slightly rncst
brown silty SAND (SM) with roots/organic
- -
-
dark \
•. / materials.
73l MiDUAL SOIL
Medium dense to dense, slightly miist. Jiht biown
- . nd (ik brown, silty SAND (SM).
• - -
\. • / 36' QuATE RRCEDEPOTS(Ot): . "
S . .. .,•,/' Dense, to very dense— slightly moist. light 'hiown
and daEk brown, silty SAN]) (Slvr).with small
- - - • Tt.naldeptli 6fbg • ;-.25'
.
) weathered quartz nodules, . •
No giuundwater .
• Backtilled with t:tlttings
F.
•
S.
- - - — - L1
CONSTRUCTION TESTING & ENGINEERING, INC. IWAL I- CohArAuchAn EMAINAeRINC TL,IINA A40 1481L enon
- III MCAtIIL A UD jollA p Ij I (scjuulje, cu lull 114o.119 411!
FRO)Wr. Three Lot Development EXCAVATOR: D;Hiebotham CTEJOU NO: 10-8791 G F.)AVA11ONuiEThOD: BACK.}IOT3 - EXe:AVATI0DxJn: 2/I6/2007 L()EX'EDBY'. DX
- - SAMPLING MFrHOD BULK EjjvATror4;
-
TEST PIT LOG: TP-5 0. LnhIratlM- 1eM.;
g •
Q 0 m 0
DESCRIPTION . . .
--
- TOPSOIL,
Medium:dense, slightly moist, iuouled litht brown
--
I
''
, to bi'own, silty fine SAND (SWf) with roots MAX / and oriu,ic materhti.
QJL
8- Mecliumden:etodense. sligh yrnti5t. tht brown
— and dark brown.iIty SAND 15,M).Total depth 4•5 lhg ' t.00se, i.y. paic gray. fine Lo eorse sand (Se-SW).- A
— .
.
No -(flth))•
. Jjacktilled itli pik OUAI I RNAR)T RRACFJ)LPOSJTS iou -
. Dense to very dcnse. siightly moist; light brown - and thtrk brown, silty SAND (SM) with small
-.25) weathered qL101-til 116dUle.q.
JJOLJRE:1 - 'I
-
CONSTRUCTION TESTING & ENGINEERING, INC
QtOIc..uICAI I CflNtIflCtID EGIIIIEIlIJs 1IIflN 41C IPlSCCIAI - -I'll -?OIt Ii IOU. S1,11 III I t3lIIflOO..ti 11111 ISO II. III - --.
-.
PItOJECI:, Thrcc L .LX I
CAVArOR: D:Biggnbotham :- citJqL'o: )G-8791G IXCAV\TION ME'I'jOD: :BA(KHOE EXC.V.VIlON r).-vrE. 2fl(ii' 'BULK'
LOC1CuEL) 13\ DIS S \MPLNG MPThOD ELEVATION:
.- — MAt TEST PIT LOG TP-6 u__
S 3 . t
'-'
- ____
o-1, -FQ F 4 0~* r---_ Medium dense. IighLly moist. rnorlcd Iilu hr%cn
------------------------
/ to brown. silty tinc SAND (SM) with roo::.ind
organic niatcrialc.. - / 1-3 RESiDUAL SOU..;-, Qi / Medium dense-to slightly moist. hrowii to /
liiijn biown. silty fine SAND (SM).
-
-
qUA JNj&Jty ThRR AC D1POSLrS tQj
Dnse;-sligbt1y moist, hiownto-
Tot0l depth .5' tbg light brown-silty line. SAND (SM).
No groundwater -
- ]3uck1i11ed with spoils
L
I ---- - -
-
. • (JONSTRUCTIONTESIING& ENGINEERiNG,
I
N
C
. C.
it"
200 WASH ANI.S1S J . o LOt AI'I')N DEPTH
--•- .
- TI'-4
1?.I
- 1-3 2q33
4-h 23.1 SM
j, •. 5 . . LOCA31ON
RESISTAN(E."R"-VAuJE
CALTEST 30!
D&Tl-1 . R-VALUE (feet) .... - C TP-I,
V LOCATION
SULFATE
.-
DEPTH RESULTS
ppm -. TP-!
-
. 45.9
CHLORIDE 00
LOCATION DlrTI-I RESULTS (feet) ppm•• . TPI
LOCATION
. . 1-3 _5.5
CONDUCTIVITY .
CALIFORN IA TEST '124
DEJ11-1 RESULTS
uS/cm •TP-I 1-3
- RESISTIVITY.
CALIFORNIA TEST 424 LOCATION DEPTH
- RFSUL1 (feet) .- ohnuciu VP-I • I3
- . 10400
MAXIMUM DRY DENSITY & OPTIMUM M
O
I
S
T
U
R
E
C
O
N
T
E
N
T
(MODIFIED PROCfOR •0 LOCATION
. OE.H OPTIMUM MOISTURE DRY OEJSITY - (feet)
-. (•,) 0 - .5-i.
- : 9.5 -
LABOR.'VI(JR\ SIMARY
rI('PNC> I.07>j
OU
:
II 5 II) IS 20 25 30 35
PERCENT MOISTURE
ASTM D1557 METHOD A B D C
) MODIFIED PROCTOR
ism; LAB SAMPLE DLVTH MAXIMUM NUMBER SOIL DESCRIPTION DRY DENSITY MOISTCRE
17078 TP-3 0.5-1 BROWN SILTY SAND 124.5 9.5
CTE JOB NO: A CONSTRUCTION TESTING & ENGINEERING, INC. DATE: 03/0?
GtC'.IC& AJ CO RJCflOMGIUE6RIUG SIOAW2ID'1
- 10-8791G
APPEND B
'GENEPJ EARTHWORK SPECIFICATIONS
AND GRADING GUIDELINES
ADVANCED GEOTECHNICAL SOLIJI1ONS, INC.
March 21,2012 Page B-i
PIW'1201-02 Report No. 1201-02-B-2
GENERAL EARTHWORK SPECIFICATIONS
I General
A General procedures and requirements for earthwork and grading are presented herein The earthwork
and grading recommendations provided in the geotechnical report are considered part of these
specifications, and where the general specifications provided herein conflict with those provided in the
geotechnical report, the recommendations in the geotechnical report shall govern ati Recommendons
provided herein and in the geotechrncal report may need to be modified depending on the conditions
:encountered during grading.
B The contractor is responsible for the satisfactory completion of all earthwork in accordance with the
project plans, specifications, applicable building codes, and local governing agency requirements Where
these requirements conflict, the strider requirethents shall govern.
C It is the contractor's responsibility to read and understand the guidelines presented herein and in the
geotechmcal report as well as the project plans and specifications Information presented in the
geotechnical report is subject to venfication during grading The information presented on the exploration
logs depicts conditions at the particular time of excavation and at the location of the excavation
Subsurface conditions present at other locations may differ, and the passage of time may result in
different subsurface conditions being encountered at the locations of the exploratory excavations The
contractor shall peform an independent investigation and evaluate the nature of the surface and
subsurface conditions to be encountered and the procedures and equipment to be used in performing his
work.
D The contractor shall have thei responsibility to provid adequate equipment and procedures to
accomplish the earthwork in accordance with applicable requirements When the quality of work is less
than that required, the Geotechnical Consultant may reject the work and may recommend that the
operations be suspended until the conditions are corrected
E Pnor to the start of grading, a qualified Geotechnical Consultant should be employed to observe
grading procedures and provide testing of the fills for conformance with the project specifications,
approved grading plan, and guidelines presented herein All remedial removals, clean-outs, removal
bottoms, keyways, and subdrain installations should be observed and documented by the Geotechnical
Consultant pnor to placing fill It is the contractor's responsibility to apprise the Geotechnical Consultant
of their schedules and notify the Geotechnical Consultaiitwhen those areas are ready for observation.
F The contractor is responsible for providing a safe environment for the Geotechnical Consultant to
observe grading and conduct tests.
ll.,SitePreparation
A 'Clearing, and Grubbing Excessive vegetation and other deleterious material shall be sufficiently
removed as required by the Geotechnical Consultant, and such materials shall be properly disposed of
offsite in a method acceptable to the owner and governing agencies Where applicable, the contractor may
obtain permission from the Geotechnical Consultant, owner, and governing agencies to dispose of
vegetation and other deleterious materials in:designated areas onsite.
ADVANCED 6EO1tCHNICALSOLIJ11ONS; INC.
"March 21,2012 PageB-2
P1W 1201-02 Report No. 120 1-02-13-2
B.- Unsuitable Soils Removals: Earth mátérials that are deemed unsuitable for the support of fill shall be
removed as necessary to the satisfaction of the Geotechnical Consultant
C Any underground structures such as cesspools, cisterns, mining shafts, tunnels, septic tanks, wells,
pipelines, other utilities, or other structures located within the limits of grading shall be removed and/or
- abandoned in accordance with the requirements of the governing agency and to the satisfaction of the
Geotechnical' Consultant.
-
D Preparation of Areas to Receive Fill After removals are completed, the exposed surfaces shall be
scarified to a depth of approximately 8 inches, watered or dried, as needed, to achieve a generally uniform
moisture content that is at or near optimum moisture content The scarified materials shall then be
- compacted to the -pro requirements and tested as specified
E All areas receiving fill shall be observed and approved by the Geotechnical Consultant pnor to the
placement of fill A licensed surveyor shall provide survey control for determining elevations of
processed areas and keyways
III Placement of Fill
- A Suitability of fill materials Any materials, denved onsite or imported, may be utilized as fill provided
that the materials have been determined to be suitable by the Geotechnical Consultant Such materials
shall be essentially free of organic matter and other deletenous materials, and be of a gradation, expansion
- potential, and/or strength that is acceptable to the Geotechnical Consultant..Fill materials shall be tested in
a laboratory approved by the Geotechnical Consultant, and import matenals shall be tested and approved
-
prior to being imported
B Generally, different fill materials shall be thoroughly mixed to provide a relatively uniform blend of
materials and prevent abrupt changes in material type Fill materials derived from benching should be
- dispersed throughout the fill area instead of placing the materials within only an equipment-width from
the cut/fill contact.
-
C Oversize Materials Rocks greater than 8 inches in largest dimension shall be disposed of offsite or be
placed in accordance with the recommendations by the Geotechnical Consultant in the areas that are
designated as suitable for oversize rock placement Rocks that are smaller than 8 inches in largest
-
dimension may be utilized in the fill provided that they are not nested and are their, quantity and
distribution are acceptable to the Geotechnical Consultant
D. The fill materials shall be placed inthin, horizontal layers such that, when compacted, shall not exceed
6 inches Each layer shall be spread evenly and shall be thoroughly mixed to obtain near uniform moisture
content and uniform blend of materials.
E Moisture Content Fill materials shall be placed at or above the optimum moisture content or as
recommended by the geotechmcal report Where the moisture content of the engineered fill is less than
recommended, water shall be added, and the fill materials shall be blended so that near uniform moisture
content is achieved lithe moisture content is above the limits specified by the.Geotechnical Consultant,
the fill materials shall be aerated by discmg, blading, or other methods until the moisture content is
acceptable.
-
ADVANCED GEOTECHNIGAL SOLLJflONS, INC.
March 21, 2012 Page B-'3
PfW1201-02 Report No. 1201-02-B2
F Each layer of fill shall be compacted to the project standards in accordance to the project specifications
and recommendations of the Geotechnical Consultant Unless otherwise specified by the Geotechnical
Consultant, the fill shall be compacted to a minimum of 90 percent of the maximum thy density as
determined by ASTM Test Method: D1557M9.
G. Benching: Where placing fill on slope exceeding a ratio of 5 to I (horizontal to vertical), the ground
should be keyed or benched The keyways and benches shall extend through all unsuitable materials-into
suitable materials such as firm materials 'or sound bedrock or as recommended by the Geotechnical
Consultant The minimum keyway width shall be 15 feet and extend into suitable matenals, or as
recommended by the geotechmcal report and approved by the Geotechnical Consultant The minimum
keyway width for fill over cut slopes is also 15 feet, or as recommended by the geotechnical report and
approved by the Geotechnical Consultant As a general rule, unless otherwise recommended by the
Geotechnical Consultant, the minimum width of the keyway shall be equal to 1/2 the height of the fill
slope.
H Slope Face The specified minimum relative compaction shall be maintained out to the finish face of
fill and stabilization fill slopes Generally, this may be achieved by overbuilding the slope and cutting
back to the compacted core The actual amount of overbwlding may vaiy as field conditions dictate
Alternately, this may be achieved by back rolling the slope face with suitable equipment or other methods
that produce the designated result Loose soil should not be allowed to build up on the slope face If
present, loose soils shall be trimmed to expose the compacted slope face
I Slope Ratio Unless otherwise approved by the Geotechnical Consultant and governing agencies,
permanent fill slopes shall be designed and constructed no steeper than 2 to 1 (horizontal to vertical)
J Natural Ground and Cut Areas Design grades that are in natural ground or in cuts should be evaluated
by the Geotechnical Consultant to determine whether scarification and processing of the ground and/or
'overéxcavatioti is needed.
K Fill matenals shall not be placed, spread, or compacted during unfavorable weather conditions When
grading is interrupted by rain, filing operations shall not resume until the Geotechnical Consultant
approves the moisture and density of the previously placed compacted fill.
IV. Cut Slopes
A The Geotechnical Consultant shall inspect all cut slopes, including fill over cut slopes, and shall be
notifid by the contractor when cut slopes are started.
-
. B. If adverse or potentially adverse conditiOns are, encountered . during grading; the . Geotechnical
COnsUltant shall investigate, evaluate, and make recommendations to mitigate the adverse conditions.
- C Unless otherwise stated in the geotechnical report, cut.slopes shall not be excavated, higher or steeper
than the requirements of the local governing agencies Short-term stability of the cut slopes and other
excavations is the contractor's responsibility. .
-
. V. Drainage .
A. Back drains and Subdrains: Back drains and subdrains shall be provided in fill as recommended by the
Geotechnical Consultant and shall be constructed in accordance with the governing agency and/or
- 0 ADVANCED GEOTECiINDCAL SOLUTIONS, INC.
March21, 2012 , Page B-4
P1W 1201-02 Report No. 120102LB2
recommendations of the :Geotechnical Consultant. The location of subdrains, especially outlets, shall be
surveyed and recorded by the Civil Engineer.
B To Drainage Positive drainage shall be established away from the top of slope Site drainage
shall not be permitted to flow over the tops of slopes
C Drainage terraces shall be constructed in compliance with the governing agency requirements and/or in
accordance with the recommendations of the Geotechnical Consultant
D. Non-ërodible interceptor'swales shall be placed at the top of-cut slopes that face'thesame direction as
the prevailing drainage.
VI. En)siofl'COntrOl
A All finish cut and fill slopes shall be protected from erosion and/or planted m accordance with the
project specifications and/or landscape architect's recommendations Such measures to protect the slope
'face shall be undertaken as soon as practical after completion of grading.
B. Duinz construction; the contractor shall maintain proper drainage and prevent the ponding of water.
The contractor shall take remedial measures to prevent the erosion of graded areas until permanent
drainage and erosion control measures have been installed.
VII.,Trench 'Excavation and 'Backfill
A Safety The contractor shall follow all OSHA requirements for safety of trench excavations Knowing
and following these requirements is the contractor's responsibility. All trench excavations or open cuts in
excess of 5 feet in depth shall be shored or laid back Trench excavations and open cuts exposing adverse
geologic conditions may require further evaluation by the Geotechnical Consultant If a contractor fails to
provide safe access for compaction testing, backfill not tested due to safety concerns maybe subject to
removal.'
B., Bedding: Bedding materials shall be non-expansive and have a Sand Equivalent greater than 30.
Where permitted by the Geotechnical Consultant, the bedding materials can be densifiedby jetting.
C backfill Jetting of backfill matenals is generally not acceptable Where permitted by the Geotechnical
Consultant, the bedding materials can be densified by jetting provided the backfill materials are granular,
free-draining.and have a Sand Equivalent greater than 30.
VLILGeotccbüicalObservation and Testing During Grading
- A.'Conaction Tesing: Fill shall be tested by the, Geotechnical Consultant' for evaluation of general
-
compliance with the recommended compaction and moisture' conditions. The tests shall be taken in the
compacted soils beneath the surface if the surficial materials are disturbed The contractor shall assist the
- Geotechnical Consultant by excavating suitable test pits for testing of compacted fill
B. 'Where 'testsindicate that the density of a layer of fill is less than required, or the moisture content not,
within specifications, the Geotechnical Consultant shall notify the contractor of the unsatisfactoiy
conditions of the fill The portions of the fill that are not within specifications shall be reworked until the
required density and/or moisture content has been attained No additional fill shall be placed until the last
-
lift of fill is tested and found to meet the project specifications and approved by the Geotechnical
Consultant
ADVANCED GEOTECIINICAL SOLUTIONS, INC.
March 2l,2012 Page B-5
P/W 1201-02 Report No. 1201-02-13-2
If, in the opinion of the Geotechnical Consultant, unsatisfactory conditions, such as adverse weather,
excessive rock or deleterious materials being placed in the fill, insufficient equipment, excessive rate of
- fill placement, results in a quality of work that is unacceptable, the consultant shall notify the contractor,
and the contractor shall rectify the conditions, and if necessary, stop work until conditions are
-
satisfactory.
Frequency of Compaction Testing: The location and frequency of tests shall be at the Geotechnical
Consultant's discretion. Generally, compaction tests shall be taken at intervals not exceeding two feet in
- fill height and 1,000 cubic yards of fill materials placed.
Compaction Test Locations: The Geotechnical Consultant shall document the approximate elevation
- and horizontal coordinates of the compaction test locations. The contractor shall coordinate with the
surveyor to assure that sufficient grade stakes are established so that the Geotechnical Consultant can
determine the test locations. Alternately, the test locations can be surveyed and the results provided to the
Geotechnical Consultant.
Areas of fill that have not been observed or tested by the Geotechnical Consultant may have to be
removed and recompacted at the contractor's expense. The depth and extent of removals will be
- determined by the Géotechnical Consultant.
Observation and testing by the Geotechnical Consultant shall be conducted during grading in order for
- the Geotechnical Consultant to state that, in his opinion, grading has been completed in accordance with
the approved geotechnical report and project specifications.
Reporting of Test Results: After completion of grading operations, the Geotechnical Consultant shall
submit reports documenting their observations during construction and test results. These reports may be
subject to review by the local governing agencies.
ADVANCED GEOTECIINICAI.. SOLUTIONS, INC.
APPENDIX C
HOMEOWNER MAINTENANCE RECOMMENDATIONS
ADVANCED GEOTECHNICAL. SOLUTIONS, INC.
Homeowners are accustomed to maintaining their homes They expect to paint their houses periodically,
replace wiring, clean out clogged plumbing, and repair roofs.Maintenance of the home site, particularly
on hillsides, should be considered on the same basis or even on a more serious basis because neglect can
result in serious consequences in most cases, lot and site maintenance can be taken care of along with
landscaping and can be carried out more economically then repair after neglect
Most slope and hillside lot problems are associated with water Uncontrolled water from a broken pipe,
cesspool or wet weather causes most damage.'Wet weather is the largest cause of slope problems,
particularly, in California where rain is intermittent, but may be torrential Therefore, drainage and erosion
control are the most important aspects of home site stability, these provisions must not be altered without
competent professional advice Further, maintenance must be carried out to assure their continued
• operation.
S
As geotechnical engineers concerned with the problems of building sites in hillside developments, we
offer the following list of recommended home protection measures as a guide to homeowners
Expansi''e.SoiIs
Some of the earth materials on site have been identified as being expansive in nature As such, these
materials are susceptible to volume changes with variations in their moisture content These soils will
swell upon the introduction of water and shrink upon drying The forces associated with these volume
changes can have significant negative impacts (in rm the form of differential movement) on foundations,
walkways, patios, and other lot improvements In recognition of this, the project developer has
constructed homes on these lots on post-tensioned or mat slabs with pier and grade beam foundation
systems, intended to help reduce the potential adverse effects of these expansive materials on the
residential structures within the project Such foundation systems are not intended to offset the forces
(and associated movement) related to expansive soil, but are intended to help soften their effects on the
structures constructed thereon.
HomeQwners purchasirig property and living in an area containing expansive, soils must assume a certain
degree of responsibility for homeowner improvements as well as for maintaining conditions around their
home Provisions should be incorporated into the design and construction of homeowner, improvements
to account for the expansive nature of the onsite soils material.. Lot maintenance and landscaping should
also be conducted in consideration of the expansive' soil characteristics. Of primary importance is
minimizing the moisture variation below all lot imprOvements. Such design, construction and
homeowner maintenance, provisions should include:
* Employirgcontràctors for homeowner improvements who design and build in recognition of
local building code and site specific soils conditions
Establishing and maintaining positive drainage away from all foundations walkways, driveways
patios, and other hardscape improvements
Avoiding the construction of planters adjacent to structural improvements Alternatively, planter
sides/bottoms can be sealed with' an impermeable membrane and drained 'away: "from the
improvements via subdrains into approved disposal areas
Sealing and maintaining construction/control joints within concrete slabs and walkways to reduce
the p 6tential for moisture infiltration into the,subgráde soils. • S
ADVANCED GEOTEClINIcAL. SOLUTIONS, INC.
+ Utilizing landscaping schemes with vegetation that requires minimal watering Alternatively,
watering should be done in a uniform manner as equally as possible on all sides of the foundation,
keeping the soil "moist" but not allowing the soil to become saturated
+ Maintaining positive drainage away from structures and providing roof gutters on all structures
with downspouts installed to carry roof runoff directly into area drains or discharged well away
fiom the structures.
Avoiding the placement of trees closer to the proposed structures than a distance of one-half the
mature height of the tree
Observation of the soil conditions around the perimeter of the structure during extremely hot/dry
or unusually wet weather conditions so that thodifications can be made in irrigation programs to
maintain relatively constant moisture conditions.
Sulfates
Homeowners should be cautioned against the import and use of certain fertilizers, soil amendments,
and/or other soils from offsite sources in the absence of specific information relating to their chemical
composition Some fertilizers have been known to leach sulfate compounds into soils otherwise
..containing,'. heg] igible" sulfate concentrations and increase the sulfate concentrations in near-surface soils
to "moderate" or "severe" levels In some cases, concrete improvements constructed in soils containing
high levels of soluble sulfates may be affected by deterioration and loss of strength
Water -Natural and Man Induced.
Water in concert with the reaction of various natural and man-made elements, can cause detrimental
effects to your structure and surrounding property. Rain water and flowing water erodes and saturates the
ground and changes the engineering characteristics of the underlying earth materials upon saturation
Excessive irrigation in concert with a rainy period is commonly associated with shallow slope failures and
- deep seated landslides, saturation of near structure soils, local ponding of water, and transportation of
water soluble substances that are deleterious to building materials including concrete, steel, wood, and
stucco. ••
Water interacting with the near surface and subsurface soils can initiate several other potentially
detrimental phenomena other then slope stability issues These may include expansion/contraction cycles,
liquefaction potential increase, hydro-collapse of soils ground surface settlement, earth material
consOlidation, and introduction of deleterious substanes.
The homeowners should be made aware of the potential problems which may develop when drainage is
altered through construction of retaining walls, swimming pools, paved walkways and patios" Ponded
water, drainage over the slope m face, leaking irrigation systems, over-watering or other conditions which
could leadto ground saturation must be avoided
Before the rainy eason arrives, ch1.eck and clear roof drains, gutters and down spouts of all
accumulated debris. Roof gutters are an important element in your arsenal against rain damage If
you do not have roof gutters and down spouts, you may elect to install them. Roofs, with their,
wide, flat area can shed tremendous quantities of water. Without gutters or other adequate
drainage, water falling from the eaves collects against foundation and basement walls
. Make sure to clear surface and terrace drainage ditches, and check them frequently during the
rainy season This task is a community responsibility
Test all drainage ditches for functioning outlet drains This should be tested with a hose and done
before the rainy season. All blockages should be removed.
ADVANCED 6EO1ICHNICAII SOWDONS, INC.
+ Check all drains at top of slopes to be sure they are clear and that water will not overflow the
slope itself, causing erosion.
+ Keep subsurface drain openings (weep-holes) clear of debris and other material which could
- block them in a storm. -
•• Check for loose fill above and below your property if you live on a slope or terrace
4 Monitor. hoses, and sprinklers. During the rainyseason, little; if any, irrigation is required.
Oversaturation of the ground is unnecessary, increases- watering costs, and can cause subsurface
drainage.
' Watch for water backup of drains inside the house and toilets during the rainy season, as this may
indicate drain or sewer blockage.
4 Never-block terrace drains and brow ditches on slopes or at the tops of cut or fill slopes. These are
designed tocariy away runoff to a place where it can be safely distributed.
4 Maintain the ground surface upsiope of lined ditches to ensure that surface water is collected in
- the ditch and is not permitted to be trapped behind or under the lining
4 Do not permit water to collect or pond On your home site Water gathering here will tend to either
seep into the ground (loosening or expanding fill or natural ground), or will overflow into the
slope and begin erosion. Once erosion is started, it is difficult to control and severedamage may
.resült.rather quickly.
4 Never áonnect roof drains, gutters, or down spouts to subsurface drains. Rather, arrange them so
that water either flows off your property in a specially designed pipe or flows out into a paved
driveway or street The water then may be dissipated over a wide surface or, preferably, may be
carried away in a paved gutter or storm drain. Subdraiñs are constructed to take 'care of ordinary
subsurface water and cannot handle the overload from roofs during a heavy rain
4 Never permit water to spill over slopes, even where this may seem to be a good way to prevent
ponding This tends to cause erosion and, in the case of fill slopes, can eat away carefully
designed i n constructed sites.
- 4 Do not cast loose 'soil or debris over slopes. Loose soil soaks up water more readily than
compacted fill It is not compacted to the same strength as the slope itself and will tend to slide
when laden with water, this may even affect the soil beneath the loose soil The sliding may clog
terrace drains below or may cause additional damage in weakening the slope If you live below a
slope, try to-be sure that loose fill is not dumped above your property.
4 Never discharge water into subsurface blanket drains close to slopes. Trench drains are
sometimes used to get rid of excess water when other means of disposing of water are not readily,
available. Overloading these drains saturates the groundand, if located close to slopes, may cause
slope-fail
'
ure in their vicinity.
4 Do not ischarge surface water into septic tanks or leaching fields. Not only are septic tanks
- constructed fora different purpose, but they will tend, beôause of their construction, to naturally
accumulate additional water from the ground during a heavy rain Overloading them artificially
- during the rainy season is bad for the same reason as subsurface subdrains, and IS doubly
- dangerous since their overflow can pose a serious health hazard In many areas, the use of septic
tanks should be,discontinued as soon as sewers are made available.
4 Practice responsible irrigation practices and do not ,over-irrigate slopes Naturally, ground cover
of ice plant and other vegetation will require some moisture during the hot summer months but
- during the wet season, irrigation can cause ice plant and other heavy ground cover to pull loose
This not only destroys the cover, but also starts serious erosion. In some areas, ice plant and other
heavy cover can cause surface sloughing when saturated due to the increase in weight and
- weakening of the near-surface soil. Planted slopes-should be planned where possible to acquire
sufficient moisture when it rains.
4' Do not let water gather against foundations, retaining walls, and basement walls. These walls are
- built to withstand the ordinary moisture in the ground and are, where necessary, accompanied by
subdrairis to carry off the excess. If water is permitted to pond against them, it may seep through
ADVANCED GEO1ECIINICAL SOUJTIONS, INC.
the wall, causing dampness and leakage inside the basement Further, it may cause the foundation
to swell up, or the water pressure could cause structural damage to walls
•• Do not try to compact soil behind walls or in trenches by flooding with water. Not only is
flooding the least efficient way of compacting fine-grained soil, but it could damage the wall
foundation or saturate the subsoil
•• Never leave a hose and sprinkler running on or near a slope, particularly during the rainy season
This will enhance ground saturation which may cause damage
. Never block ditches which have been graded around your, house or the lot pad These shallow
ditches have been put there for the purpose of quickly removing water toward the driveway, street
or other positive outlet By all means, do not let water become ponded above.slopes by blocked
ditches.
4 Seeding and planting of the slopes should be planned to achieve, as rapidly as possible, a well-
established and deep-rooted vegetal cover, requiring minimal watering.
+ It should be the responsibility of the landscape architect to provide such plants initially and of the
residents to maintain such planting Alteration of such a planting scheme is at the resident's risk
4 The resident is responsible for proper imgation and for maintenance and repair of properly
installed imgation systems Leaks should be fixed immediately. Residents must undertake a
program to eliminate burrowing animals. This must be an ongoing program in order to promote
slope stability. The burrowing animal control program 'should:be conducted by a licensed
exterminator and/or landscape professional with expense in hill side maintenance. S
Gèotechnical Review
Due to. the fact that soil types may vary with depth, it is recommended thatplàns for, the construction of
rear yard improvements (swimming pools, spas, barbecue pits patios, etc), be reviewed by a geotechnical
engiiieér.who is familiar with local conditions and the current, standard-of practice in the vicinity of your
homes
In conclusion, your neighbor's slope, above or below your property, is as important to you as thei slope
that is within your property lines For this reason, it is desirable to develop a cooperative attitude
regarding hillside maintenance, and we recommend developing a "good neighbor" policy. Should
conditions develop off"your'.property, which are undesirable from indications given above, necessary
action should be taken by you to insure that prompt remedial measures are taken Landscaping of your
property, is ,imp6rtarit to enhance slope and foundation stability and to prevent erosion of ttie near surface
soils In addition landscape improvements should provide for efficient drainage to a controlled discharge
location downhill of residential improvements and soil slopes.
Additionally, recommendations contained in the Geotechnical Engineering. Study report apply to all
future residential site improvements, and we advise that you include consultation with a qualified
professional in planning, design, and construction of any improvements Such improvements include
patios, swimming pools, decks, etc, as well as building structures and all changes in the site configuration
- requiring earth cut or fill construction.
ADVANCED EOIECHNICAL. SOUJEIONS, INC.
TIONS,' INC. ADVANCED GEOTECIINICAL SOUJ
25109 Jefferson Avenue, Suite 220 GS Murrieta, California 92562 / Telephone: (619) 708-1649 Fax: (714) 409-3287
NEW POINTE COMMUNITIES, INC. April 11, 2012
16880 West Bernardo Drive, Suite 230 ' P1W 1201-02
San Diego, CA 92127 Report No. 1201-02-B-3
Attention: Mr. Scot Sandstrom
Subject: Foundation Design Review Letter Proposed Single Family Residences, PcI 2 (1373
Magnolia Ave) and PcI 3 (1377 Magnolia Ave.) Carlsbad, California
References: I) Innovative Structural Engineering (ISE) 1377 Magnolia Ave Pci 3, dated March 23,
- - 2012(Sheets SCS, SI, & SD])
Innovative Structural Engineering (ISE) 1373 Magnolia Ave PcI 2, dated March 29,
2012(Sheets SCS, Si, & SD])
Geotechnical Investigation and Foundation Design Recommendations for Proposed
Single-Family Residences, Parcel 2 and 3, 1369 Magnolia Avenue, Carlsbad, California
prepared by Advanced Geotechnical Solutions, Inc. (AGS) dated March 21, 2012 (P/W
1201-02)
Gentlemen:
In accordance with your request, Advanced Geotechnical Solutions, Inc.'s (AGS) has reviewed the
Foundation Plans for PcI 2 (1373 Magnolia Ave.) and PcI 3 (1377 Magnolia Ave.) prepared by
Innovative Structural Engineering (ISE), dated March 29 and March 23, 2012. Specifically, AGS has
reviewed sheets SCS, SI and SDI of each plan set for conformance to the recommendations presented in
the,Geotechnical Investigation and Foundation Design Recommendations report (Ref. 3). Based upon our
review it is our opinion that the proposed foundation designs were prepared in general accordance with
the recommendations presented in the referenced report.
Advanced Geotechnical Solutions, Inc. appreciates the opportunity to provide you with geotechnical
consulting services and professional opinions. If you have any questions, please contact the undersigned
at (619) 708-1649.
Respectfully,Submitted,
Alan R'l eVotech ica olutio , rnc-.
JEtF4E-Y-A. CH Y,Vic resident
RCE46544/RG eg. Exp. 6-30-13
Distribution: (6) Addressee
A.
r No.23,4
EXp 6-30.13 .1
ORANGE AND L.A. COUNTIES INLAND EMPIRE SAN DIEGO AND IMPERIAL COUNTIES
(714) 786-5661 (619) 708-1649 (619) 850-3980