HomeMy WebLinkAboutCT 16-10; HOME AVENUE; SECOND REVISED GEOTECHNICAL INVESTIGATION AND FOUNDATION DESIGN RECOMMENDATIONS; 2017-12-28McKellar McGowan
888 Prospect St. #330
La Jolla CA 92037
Attention: Mr. Chris McKellar
Subject: Second Revised Geotechnical Investigation and Foundation Design
Recommendations for Proposed Residential Multi-Family Podium Structure (800
Grand Ave.) and Single Family (Home Ave.), 800 Grand Project, Carlsbad,
California
Reference: See Appendix
Gentlemen,
In accordance with your request, presented herein is Advanced Geotechnical Solutions, lnc.'s (AGS) 2ND
Revised Geotechnical Investigation and Foundation Design Recommendations for the proposed residential
structures to be located at 800 Grand A venue, Carlsbad, California. Specifically, this report has been revised
in response to comments from the Land Development Engineering Department of the City of Carlsbad. As
we understand the project the site will be separated into two pieces: the Home Avenue portion (5 unit single
family residential) and the 800 Grand portion (partially subterranean podium structure).
The recommendations presented in the following report are based on a limited subsurface investigation
performed by AGS and associated laboratory testing. It is AGS's opinion, from a geotechnical standpoint,
the subject site is suitable for construction of the proposed residences, provided the recommendations
presented in this report are incorporated into the design, planning and construction phases of site
development. Included in this report are: 1) engineering characteristics of the onsite soils; 2) unsuitable
soil removal recommendations; 3) grading recommendations; 4) foundation design recommendations; and
5) storm water infiltration feasibility analysis.
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) 867-0487.
JEFFREY A. CHANEY, President
GE 2314, Reg. Exp. 6-30-19
Distribution: (3) Addressee
Attachments: Figure I -Site Location Map;
Figure 2 -Geologic Map and Exploration Plan;
Plate I -Site Geologic Map; Plate 2 -Cross-Sections;
Appendix A -Field and Laboratory Data:
PAUL DERISI, Vice President
CEG 2536, Reg. Exp. 5-31-19 ~~r.1VEr'\
JAN O 9 2018
Appendix B -General Earthwork Specifications & Grading Guidelines;
Appendix C -Homeowner Maintenance Recommendations; LAND OEVELOPMr
ENGINt:.ERING Appendix D -Preliminary Storm Water Infiltration Feasibility Analysis
ORANGE AND L.A . COUNTIES
(7 14) 786-5661
INLAND EMPIRE
(619) 867-0487
SAN DIEGO AND IMPERIAL COUNTIES
(6 19) 867-0487
REVISED GEOTECHNICAL INVESTIGATION AND FOUNDATION
DESIGN RECOMMENDATIONS FOR PROPOSED RESIDENTIAL MULTI-
FAMILY PODIUM STRUCTURE (Grand Ave.) and SINGLE FAMILY (Home
Ave.)
800 GRAND PROJECT
CARLSBAD, CALIFORNIA
December 28, 2017
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Page I
Report No. I 607-03-B-2R2
1.0 SCOPE OF SERVICES
This revised study is aimed at providing geotechnical information as it relates to: I) existing site soil conditions;
2) discussion of the geologic units onsite; 3) seismic hazard analys is; 4) engineering characteristics of the on site
soils; 5) excavation characteristics of earth materials; 6) seismic design parameters for use in the structural design
of the proposed single-family residences; 7) foundation design parameters for the proposed conventional shallow
foundation systems; and 8) storm water infiltration onsite.
The scope of our study included the following tasks:
2.0
► Review of pertinent published and unpublished geologic and geotechnical literature, maps, and aerial
photographs.
► Excavate, log, and sample: two (2) exploratory borings (TB-1 and TB-2) with a limited access tripod
drill rig and four Hollowstem Auger Borings (HS-I thru HS-4) excavated with a truck mounted drill rig
CME 55 (Appendix A).
► Laboratory testing ofrepresentative bulk and "undisturbed" ring samples including moisture content and
density, maximum density and optimum moisture content, shear strength, and chemical/resistivity
analysis. (Appendix A)
► Excavate three (3) percolation test borings with tripod rig or with a truck mounted Hollowstem Auger
to conduct infiltration testing in accordance with Appendix D of the final Model BMP Design Manual
for the San Diego Region, adopted by the City of Carlsbad.
► Conduct a geotechnical engineering and geologic hazard analysis of the site.
► Conduct a limited seismicity analysis.
► Determine the site-specific seismic design parameters for use in the structural design.
► Determine design parameters of onsite soils as a foundation medium including bearing and friction
values for foundation soils.
► Preparation of a geotechnical foundation investigation report with exhibits summarizing our findings.
This report would be suitable for design, contractor bidding, and regulatory review.
GEOTECHNICAL STUDY LIMITATIONS
The conclusions and recommendations in this report are professional opinions based on our field investigation,
associated lab testing, review of referenced geotechnical maps, and our experience in the area.
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 services.
3.0 SITE LOCATION AND DESCRIPTION
The "L" shaped 1.38 acre site is located at 800 Grand Avenue, Carlsbad, California (Figure I, Site Location
Map). The site is bounded by Grand Avenue to the south, commercial and apartment building to the east and
west and to the north by an apartment building and Home A venue. The larger southerly portion (Parcel A-called
the Grand Avenue portion) is occupied by three older slab-on-grade, two story wood framed office buildings.
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The northerly portion of the site (Parcel B-called the Home Avenue portion) consists of an asphaltic concrete
parking lot with minor areas of landscaping. T he existing driveways and parking areas cons ist of approximately
5 to 6 inches of concrete pavement. Based upon our review of Google Earth imagery the elevations onsite range
from a high of 64MSL at the northeastern property corner, to a low of 57 MSL at the northwest corner of the
site.
4.0 PROPOSED DEVELOPMENT
As AGS understand the project, it is anticipated that the existing commercial structures will be demolished and
the lots will be re-graded to two separate developments. The larger "Parcel A" called the 800 Grand portion lot
will support a Multi-Family Podium structure. The proposed podium will consist of a partially subterranean
garage imbedded approximately 4 to 6 feet from existing grade (See Cross-Sections, Plate 2). Above the partially
subterranean garage will be a three story of condominium podium. The condominiums will be wood frame
construction with access via the garage entryways at street level with both elevators and stairs.
The "Parcel B" called the Home Avenue portion is located in the smaller northern "panhandle" portion of the
site. It will consist of 5 single family, wood frame two-story s ing le-family residential structures supported by
conventional or post-tensioned slab-on-grade foundation systems.
Grading on both parcels is anticipated to consist of cuts and fills of two to 9 feet, or less.
5.0 FIELD AND LABO RA TORY INVESTIGATION
5.1. Subsurface Exploration
AGS conducted a limited subsurface exploration at the subject site on September I 0, 20 I 6 to evaluate
the onsite soil conditions. Five exploratory borings were excavated to depths ranging from 6 to 2 1.5
feet bgs with a truck mounted Hollowstem Auger rig (HS-I through HS-4) and with a limited access
tripod drill rig (TB-I and TB-2). The approximate locations of the exploratory borings are shown on
Plate I with boring logs presented in Appendix A.
5.2. Laboratory Investigation
Representative "undisturbed" ring samples, and bulk samples were obtained from the borings for
laboratory testing to determine: in-situ moisture content and density; shear strengths; maximum density
and optimum moisture content; soluble sulfate/chloride content; and resistivity. Results of laboratory
testing are presented in Appendix A.
5.3. Infiltration Testing
Two additional borings were excavated adjacent to soil borings TB-I and TB-2 to depths of
approximately 9 feet and 5 feet below existing grade. A total of three infiltration tests were conducted
(two adjacent to Grand Avenue and one in the Home Ave portion of the development). Infiltration
testing was conducted in accordance with the Borehole Percolation Testing Method described in
Appendix D of the San Diego Region BMP Design Manual and Riverside County Percolation Test
Methods (2011 ). Preliminary infiltration rates were calculated utilizing the Porchet M ethod. A more
detailed discussion of the site specific infiltration testing along with supporting worksheets, field data
and calculations are presented in Appendix D. Test locations are shown on Plate I.
ADVANCED GEOTECHNICAL SOLUTIONS, INC.
SITE LOCATION MAP
800 GRAND AVE
CARLSBAD, CALIFORNIA
SOURCE MAP(S): TOPOGRAPHIC MAP OF THE
SAN LUIS REY 7.5 MINUTE QUADRANGLE
SAN DIEGO COUNTY, CALIFRONIA
FIGURE 1
~~GS ADVANCED GEOTECHNICAL SOLUTIONS, INC.
485 Corporate Drive, Suite B, Escondido Ca, 920925
Telephone: (6 I 9) 726-1046 fax: (7 14) 409-3287
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6.0 ENGINEERING GEOLOGY
6.1. Geologic and Geomorphic Setting
The subject site is situated within the Peninsular Ranges Geomorphic Province. The Peninsular Ranges
province occupies the southwestern portion of Cali fo rnia and extends southward to the southern tip of
Baja California. 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 boring logs included in Appendix A.
Based on our site reconnaissance, subsurface excavations, and review of the referenced geologic map,
the site is underlain to the depths explored by old paralic deposits (marine terrace deposits) which are
locally overlain by a relatively thin veneer of un documented fill soils. A site geologic map is presented
in Figure 2.
6.2.l. Artificial Fill-Undocumented (afu)
Undocumented fill soils were encountered in the onsite excavations and observed to overlie the
old paralic deposits. As encountered in our limited subsurface investigation, the undocumented
fill soils were approximately one foot thick, it is anticipated that thicker sequences (4 to 6 feet)
may be present onsite within the existing utility lines. As encountered, these materials generally
consisted of brown, dry to slightly most, fine-grained sand with some silt in a loose condition.
6.2.2. Old Paralic Deposits (Map symbol Qop6)
The site is underlain to maximum depth explored by old paralic deposits. These materials can
generally be described as orange brown to light brownish gray, slightly moist to moist, medium
dense to dense, fine-grained sand. At the contact between the old paralic deposits and the
underlying Santiago formation was a coarse grained sandy to gravelly lag deposit which was
found to be approximately six to twelve inches thick and saturated.
6.2.3. Santiago Formation (Tsa)
The bedrock unit underlying the site is assigned to the Eocene-aged Santiago Form ation. The
unit is composed predominately of a relatively massive grey green sandy silt stone that is fine-
to coarse-grained to a silty claystone. Subunits of sandy siltstone and s ilty claystone are
common throughout.
ADVANCED GEOTECHNICAL SOLUTIONS, INC.
SOURCE MAP(S): GEOLOGIC MAP OF THE
OCEANSIDE, 30x60 QUADRANGLE
CALIFORNIA, KENNEDY AND TAN, 2005
SITE GEOLOGIC MAP
800 GRAND AVE.
CARLSBAD, CALIFORNIA
FIGURE 2
~~GS ADVANCED GEOTECHNICAL SOLUTIONS, INC.
485 Corporate drive, Suite B, Escondido Ca, 92025
. Telephone: (619) 726-1046 Fax: (7 14)409-3287
P/W 1607-03 Report No. 1607-03-B-l
December 28.2017
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6.3. Groundwater/Saturated Soils
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Report No. 1607-03-B-2R2
Groundwater/saturated soils were enco untered in exploratory soil borings on site. Groundwater was
found to vary from I 4fbg (southeast corner of the site) adjacent to Grand Street to 16.5 fbg feet from
existing grade in the northwest portion of the site adjacent to Home Avenue. It is our opinion that the
groundwater is collecting in the coarser lag deposits on top of the Santiago formation and is generally
draining in a northwesterly direction towards Buena Vista Lagoon. It should be noted that the
groundwater level may vary, due to fluctuations in precipitation, irrigation practices, infiltration water
from adjacent properties, or factors not evident at the time of our field explorations.
6.4. Non-seismic Geologic Hazards
6.4.1. Mass Wasting
Given the flat nature of the site 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.
6.4.3. Subsidence/Ground Fissuring
Due to the presence of the relatively dense underlying materials and the removals proposed
herein, the potential for subsidence and ground fissuring due to settleme nt 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 severity 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 soi I characteristics. The seismic hazard may be primary, such as surface rupture and/or
ground shaking, or secondary, such as liquefaction or dynamic 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 the California Building Code (2016), CDMG (2008), and Martin and
Lew (1998).
6.5.l. 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 4. 7 miles west of the subject site. Accordingly, the potential for fault surface
rupture on the subject site is considered to be low to remote. This conclusion is based on
literature review and aerial photograph analysis.
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7.0
6.5.2. Seismicity
As noted, the site is within the tectonically active southern California area, and is approximately
4. 7 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, and industrial) are usually
designed according to the California Building Code (2016) and that of the controlling local
agency. However, liquefaction/seismic slope stability analyses, critical structures, water tanks
and unusual structural designs will likely require site specific ground motion input.
6.5.3. Liquefaction
In consideration of the proposed remedial grading recommendations presented herein and the
relatively dense nature and age (middle to late Pleistocene) of the deeper underlying old paralic
deposits at the project site, the potential for seismically induced liquefaction is considered low.
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 subject site is considered low due to the presence of
the old paralic deposits and the proposed removals of loose, sandy soils.
6.5.5. Seismically Induced Landsliding
The topography on site is flat. As such, the potential for landsliding on site is considered nil.
6.5.6. Tsunamis
Our review of the 2009 Tsunami Inundation Map for Emergency Planning, Point Loma
Quadrangle, prepared by CalEMA, indicates the project site is not located within the tsunami
inundation line. This line represents the maximum considered tsunami run-up from a number of
local and distant tsunami sources. The suite of tsunami source events selected for modeling
represent possible but extreme and rare events. As such, no information about the probability
of any tsunami affecting any area within a specific period of time is provided. In addition, the
map does not represent inundation from a single scenario event. Rather, it was created by
combining inundation results for an ensemble of source events affecting a region.
Recent studies indicate that significant run-up heights in the Carlsbad area due to distant tsunami
source events are highly unlikely in consideration of the offshore topography and presence of
islands along the southern California borderlands. In addition, the protected shoreline in the
project vicinity will further inhibit significant run-up heights during a tsunami event.
Accordingly, it is our opinion that tsunamis are not a significant risk at the project site.
GEOTECHNICAL ENGINEERING
Presented herein is a general discussion of the geotechnical properties of the various soil types and the analytic
methods used in this report.
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7.1. Material Properties
7.1.1. Excavation Characteristics
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Report No. I 607-03-B-2R2
Based on our previous experience with similar projects near the subject site and the information
gathered in preparing this report, it is our opinion that the undocumented fill soils and Old
Paralic Deposits are readily excavatable with conventional grading equipment. However, it
should be anticipated that well cemented zones could be encountered within the old paralic
deposits that may be difficult to excavate. Specialized grading equipment (large excavators
and/or bulldozers) may be necessary to efficiently excavate portions of the old paralic deposits.
7.1.2. Compressibility
The near surface undocumented fill soils and the weathered one to two feet of the Old Paralic
deposits are considered to be moderately compressible in their present condition.
Compressibility of the unweathered old paralic deposits is not a geotechnical design concern for
the proposed structures.
7.1.3. Collapse Potential/Hydro-Consolidation
Given the relatively thin veneer of undocumented fill soils on top of the generally dense
formational materials, and the removals proposed herein, the potential for hydro-consolidation
is considered remote at the subject site.
7.1.4. Expansion Potential
Based on our previous experience in the area with similar materials, the onsite soils exposed
within the upper IO to 15 feet will likely exhibit a "very low to low" expansion potential.
7.1.5. Shear Strength
Based upon our laboratory testing and our previous experience in the area with similar soils, the
following are proposed shear strengths for compacted fill and old paralic deposits.
TABLE 7.1.5
SHEAR STRENGTHS
Material Cohesion Friction Angle
(psf) (degrees)
Compacted Fill 150 34
Old Paralic Deposits 250 35
7.1.6. Chemical/Resistivity Test Results
Preliminary soluble sulfate and chloride, and res1st1v1ty testing was conducted on a
representative bulk sample obtained during subsurface exploration (Appendix A). Based upon
the test results and our previous experience in the area it is anticipated that the onsite soil will
exhibit "negligible" sulfate concentrations when classified in accordance with ACI 318-05 Table
4.3.1 (per 2016 CBC).
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8.0
Testing reveals that so il on site has a "low" corrosion potential to metal construction materials
in direct contact to the ons ite soils.
7.1.7. Earthwork Adjustments
It is anticipated that the onsite fill soils and weathered old paralic deposits will shrink on the
order of 5 to 10 percent when re-compacted. The fresher, old paralic deposits are anticipated to
bulk on the order of 4 to 8 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. F inal design should be based upon
representative sampl ing of the as-graded soils.
7 .1.9. Infiltration Potential
AGS conducted three borehole percolation tests (P-1 and P-2) in the southern portion of the site
(Grand Avenue) and one test (HSP-3) in the northern portion of the site (Horne Avenue), in
accordance with the testing methods described in Appendix D of the BMP Design Manual.
Based on the results of our subsurface investigation, it is anticipated that the dense upper
portions of the sandy Old Paralic deposits onsite possess relatively high to moderate infiltration
rates. Infiltration rates were calculated using the Porchet method. Measured infiltration rates
varied from between 0. 77 in/hr and 2.83 in/hr.
CONCLUSIONS AND RECOMMENDATIONS
Construction of the proposed "Podium" structure (Grand Avenue) and the single family residential structures
(Home Avenue) and associated improvements are considered feasible, from a geotechnical 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 s ite 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 sens1t1ve structures, all undocumented fill soils and highly
weathered formational materials should be removed. It is anticipated that the upper I to 3 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 I imits 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 conducted prior to fill placement. In general, soils removed during remedial grading
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will be suitable for reuse in compacted fills, provided they are properly moisture conditioned
and do not contain deleterious materials. Grading shal l 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.
8.2. Earthwork Considerations
8.2.1. 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. All fill to be placed below subdrains
should be compacted to at least 93 percent of maximum dry density. Compaction shall be
achieved at slightly above the optimum moisture content, and as generally discussed in the
attached Earthwork Specifications (Appendix E).
8.2.2. Benching
Where the natural slope is steeper than 5-horizontal to I -vertical and where determined by the
project Geotechnical Engineer or Engineering Geologist, compacted fill material shall be keyed
and benched into competent materials.
8.2.3. Mixing and Moisture Control
In order to prevent layering of different soil types and/or different moisture contents, mixing
and moisture control of materials may be necessary. The preparation of the earth materials
through mixing and moisture control should be accomplished prior to and as part of the
compaction of each fill lift. Water trucks or other water delivery means may be necessary for
moisture control. Discing may be required when either excessively dry or wet materials are
encountered.
8.2.4. Haul Roads
All haul roads, ramp fills, and tailing areas shall be removed prior to engineered fill placement.
8.2.5. Import Soils
Import soils, if required, should consist of clean, structural quality, compactable materials
similar to the on-s ite soils and should be free of trash, debris or other objectionable materials.
Import soils should be tested and approved by the geotechnical consultant prior to importing. At
least three working days should be allowed in order for the geotechnical consultant to sample
and test the potential import material.
8.2.6. Utility Trench Excavation and Backfill
All utility trenches should be shored or laid back in accordance with applicable Cal/OSHA
standards. Excavations in bedrock areas should be made in consideration ofunderlying geologic
structure. The geotechnical consultant should be consulted on these issues during construction.
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Mainline and lateral utility trench backfill should be compacted to at least 90 percent of
maximum dry dens ity as determined by ASTM D 1557. Onsite soils will not be suitable for use
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 the soils.
Compaction should be accomplished by mechanical means. Jetting of native soils will not be
acceptable.
To reduce moisture penetration beneath the slab-on-grade areas, shallow utility trenches should
be backfilled with lean concrete or concrete slurry where they intercept the foundation
perimeter. As an alternative, such excavations can be backfilled with native soils, moisture-
conditioned to over optimum, and compacted to a minimum of 90 percent relative compaction.
8.3. Design Recommendations
The following design recommendations have been separated due to the different building types. Grand
Avenue will consist of a "Podium" structure with a partially subterranean structure and Horne Avenue
with will be conventional slab-on-grade wood frame structures.
8.3.1. Grand Avenue-Podium Structure
It is our understanding that the proposed Grand Avenue condominium building will consist of a
"Podium" with a partially subterranean "Mat" slab-on-grade foundation system. The podium
will support the three-story wood-frame residential structure. It is anticipated that the foundation
systems will likely be a "Mat" system with CMU basement walls. In addition to the structures,
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.
8.3.1.1. Foundation Design Criteria Podium Structure -Grand Avenue
The residential condominium podium structure can be supported on a shallow "mat"
foundation system. For preliminary design, the expansion potential of the underlying
soils can be considered "Very Low" to "Low". The following values may be used in
the foundation design.
Allowable Bearing:
Lateral Bearing:
Sliding Coefficient:
Settlement:
Differential:
3000 lbs./sq.ft.
350 lbs./sq.ft. at a depth of 12 inches plus
200 lbs./sq.ft. for each additional 12 inches
embedment to a maximum of 5000 lbs./sq.ft.
0.37
Total = 3/4 inch
3/8 inch in 20 feet
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The above values may be increased as allowed by Code to resist transie nt loads such as
wind o r seismic. Building Code and structural design considerations may govern. Depth
and reinforcement requirements should be evaluated by the Structural Engineer.
Based upon the onsite soil conditions and information supplied by the 2016 CBC,
conventiona l foundation systems should be designed in accordance with Section 8.2.1.1
and the following recommendations.
► Continuous Footings-
Depth-Minimum of24 inches
Width-Minimum of 18 inches
Reinforcement-Minimum four No.5 rebar's, two top and two bottom
► Isolated Spread Footf~gs-Minimum of 24 inches wide and 24 inches deep
(Reinforcement per structural engineer)
► Garage Slab-Minimum of 5 inches thick with # 3 rebar on 15 inch centers
both ways. Consideration should be given to underlay the garage slab with a
mo isture barrier.
► Garage Slab Entrance-A grade bea m reinforced continuously w ith the
garage footings shall be constructed across the garage entrances, tying
together the ends of the perimeter footings and between indiv idual spread
footings. This grade beam should be embedded a minimum of 18 inches. 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.
8.3.2. Home Avenue-Conventional Slab-On-Grade
The conventional slab-on-grade residential one to two story structures can be supported on
conventional shallow foundation and slab-on-grade systems. For preliminary design, the
expansion potential of the underlying soils can be considered "Very Low" to "Low". The
following values may be used in the foundation design.
Allowable Bearing:
Lateral Bearing:
Sliding Coefficient:
Settlement:
Differential:
2000 lbs./sq. ft.
300 lbs./sq.ft. at a depth of I 2 inches plus
200 lbs./sq.ft. for each additional 12 inches
embedment to a maximum of2000 lbs./sq.ft.
0.40
Total = 3/4 inch
3/8 inch in 20 feet
The above values may be increased as allowed by Code to resist transient loads such as w ind or
seismic. Building Code and structural design considerations may govern. Depth and
reinforcement requirements should be evaluated by the Structural Engineer. Based upon the
ADVANCED GEOTECHNICAL SOLUTIONS, INC.
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onsite so il conditions and information supplied by the 2013 CBC, conventiona l foundation
systems should be designed in accordance w ith Section 8.2.1 and the follow in g
recommendations.
► Interior and exterior footings for one-story structures should be a minimum of
12 inches wide and extend to a depth of at least 12 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.
► lnterior and exterior footings for two-story structures should be a minimum of
15 inches w ide and extend to a depth ofat least 18 inches below lowest adjacent
grade. Footing reinforceme nt 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.
► Interior and exterior footings for three-story structures should be a minimum of
18 inches wide and extend to a depth ofat least 24 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 rei nforcing
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 mainta ined. 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.
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8.4
8.5
Seismic Design Parameters
The following seismic design parameters are presented to be code compliant to the California B uilding
Code (2016). The subject parcels have been identified to be Site C lass "C" in accordance with CBC,
2013, Section 161 3.3.2 and ASCE 7, Chapter 20. The lots are located at Latitude 33.1633°N, and
Longitude 11 7.3462° W. Utilizing this information, the United States Geological Survey (USGS) web
tool (http://earthquake.usgs.gov/hazards/designmaps/) and ASCE 7 criterion, the mapped seismic
acceleration parameters Ss, for 0.2 seconds and S,, for 1.0 second period (CBC, 2016, 1613.3.1) for
Risk-Targeted Maximum Considered Earthquake (MCfa) can be detennined. The mapped acceleration
parameters are provided for Site Class "B". Adjustments for other Site Classes are made, as needed, by
utilizing Site Coefficients Fa and fv fo r determination of MCER spectral response acceleration
parameters SMs for short periods and SM1 for 1.0 second period (CBC, 2016 1613.3.3). Five-percent
damped design spectral response acceleration parameters Sos for short periods and S01 for 1.0 second
period can be determined from the equations in C BC, 20 I 3, Section 161 3.3.4.
TABLE8.4
SEISMIC DESIGN CRITERIA
Mapped Spectral Acceleration (0.2 sec Period), Ss 1.1 47g
Mapped Spectral Acceleration (1.0 sec Period), S1 0.440g
Site Coefficient, Fa 1.000
Site Coefficient, Fv 1.360
MCE Spectral Response Acceleration (0.2 sec Period), SMs 1.1 47g
MCE Spectral Response Acceleration ( 1.0 sec Period), SM 1 0.598g
Design Spectral Response Acceleration (0.2 sec Period), SDs 0.764g
Design Spectral Response Acceleration (1.0 sec Period), SD1 0.399g
Using the United States Geological Survey (USGS) web-based ground motion calculator, the site class
modified PGAM (FroA *PGA) was determined to be 0.454g.
Deepened Footings and Structural Setbacks
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 soi ls and long-term (secondary) settlement. Most building codes,
including the California Building Code (CBC), require that structures be set back or footings deepened,
where subject to the influence of these natural processes.
Grading plans for the subject site were not available fo r review at the time of this report, but as AGS
understands the project, no slopes greater than 5 feet are planned. If foundations for residential structures
ADVANCED GEOTECHNICAL SOLUTIONS, INC.
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Report No. I 607-03-B-2R2
are to exist in proximity to slopes, the footings should be embedded to satisfy the requirements presented
in Figure 4.
FACE OF
STRUCTURE
TOE OF SLOPE
H/2 BUT NEED NOT
EXCEED J 5 FT.
MAX.
FIGURE 4
FACE OF FOOTING
TOP OF
SLOPE
H/3 BUT NEED NOT EXCEED 40 FT. MAX. H
j
8.6 Under Slab
8.7
8.8
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 I 0-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 vapor to acceptable levels. The use of this system or other
systems, materials or techniques can be considered, at the discretion of the designer, provided the system
reduces the vapor transmission rates to acceptable levels.
Concrete Design
Laboratory testing and our previous experience in the general area indicates onsite soils likely exhibit a
"negligible" sulfate exposure when classified in accordance with ACI 318-11 Table 4.2.1. 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
mitigate the potential for increased sulfate concentrations to onsite soil s as a result of the future
homeowner's actions.
Corrosion
Resistivity tests performed indicate that the onsite soils possess a "low" corrosion potential to buried
metallic materials. It is our understanding that only the last ten feet of the domestic and fire waterlines
ADVANCED GEOTECHNICAL SOLUTIONS, INC.
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Report No. I 607-03-B-2R2
8.9
wi ll be metallic, with the remainder of these lines being non-meta llic. Further, the proposed plumbing
for each structure will not be located under s lab but will be located in the walls and roofs. Provided that
all metallic piping is wrapped with a suitable corrosion inhibiting material (foam, plastic sleeve, tape, or
similar products) and that non-aggressive backfill (sand) soils are placed around all metallic pipe, no
other requireme nts are deemed necessary to address the "moderately'· corrosive soils found onsite.
Retaining Walls
At the time of this report, grading plans were not available for our review. As AGS understands the
project, no buried structures or retaining walls are anticipated. The fol lowing earth pressures are
recommended for design if retaining walls are proposed onsite. At rest earth pressures should be used in
the design of restrained basement walls.
Static Case
Compacted Fill/Old Paralic Deposits (34° at 125pcf):
Rankine
Level Backfill Coefficients
Coefficient of Active Pressure: Ka= 0.28
Coefficient of Passive Pressure: Kr = 3.54
Coefficient of At Rest Pressure: K0 = 0.44
Seismic Case
Equivalent Fluid
Pressure (psf/lin.ft.)
35
442
55
In addition to the above static pressures, unrestrained retaining walls should be designed to resist seismic
loading. In order to be considered unrestrained, retaining walls should be allowed to rotate a minimum
of roughly 0.004 times the wall height. The seismic load can be modeled as a thrust load applied at a
point 0.6H above the base of the wall, where H is equal to the height of the wall. This seismic load (in
pounds per lineal foot of wall) is represented by the following equation:
Pe =½ *y*H2 *k11
Where:
H = Height of the wall (feet)
y = soil density = 125 pounds per cubic foot (pct)
k11 = ½ * peak horizonta l ground acceleration = ½ * 0.537g
Walls should be designed to resist the combined effects of static pressures and the above seismic
thrust load.
A bearing value of 3,000 psf may be used for design of basement waUs. A value of 0.40 may be used to
model the frictional between the soil and concrete. For sliding passive pressure both passive and friction
can be combined to a maximum of 2/3 the total.
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 wal) 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 or equivalent).
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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 wa ll. In addition to th e 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 wa ll face. Retaining wall backfi ll and drains should be constructed in general conformance to
RTW-A. Final design of the waterproofing should be determined by the Architect.
H
WATERPROOFING
MEMBRANE
qi .
· ·• min. .~ I
;,. t·············l. ....
;. · j . SE:Ll:C'r 1
;, j : BACKFILL\
• · -(E1<20 & :
,1. I · S(>20) \ \. . ·-. · · I · · H/2 · · !
r3' NATIVE
BACKFILL
(El.::_50)
I
"' ~ . ...•.......➔, I · min. : : '.... . \
1 :1 (H:V) OR FLATTER
I . . . , ·~ i • . . \
-~-\$:..,.'i,;,...'.s,""',(r;,-. -~·:.·.~ ,,g,. . I
;,*;,~~/~-LS:2J DRAIN (1)
VER 1.0
~ \ .1 V
NOTES: (1) DRAIN: 4-INCH PERFORATED ABS OR PVC PIPE OR APPROVED EOUIVAl.£NT
SUBSTfTUTE PLACED PERFORATIONS DOWN AND SURROUNDED BY A
MINIMUM OF 1 CUBIC FEET OF 314 INCH ROCK OR APPROVED EQUIVAl.£N T
SUBSTITUTE AND WRAPPED IN MIRAFI 140 FILTER FABRIC OR APPROVED EQUIVALENT SUBSTITUTE
RETAININ G WALL
ALT. A -SELECT BACKFILL AIJ\.'ANCIJ)GfOlIDNtCAI so..um:~. l/\1(,.
ADVANCED GEOTECHNICAL SOLUTIONS, INC.
DETAIL
RTW-A
NTS
December 28, 2017
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Report No. I 607-03-B-2R2
The retaining walls 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 DI 557. Flooding or
jet1ing of backfill materials generally do not result in the required degree and uniformity of
compaction and, therefore, is not recommended. The soils engineer 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 pro perly backfilled and compacted.
8.10 Utility Trench Excavation
8.11
All utility trenches should be shored or laid back in accordance with applicable CAL/OSHA standards.
Excavations in bedrock areas should be made in consideration of underlying geologic structure. AGS
should be consulted on these issues during construction.
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 as bedding material
but will be s uitable 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 the soils. Compaction should be accomplished by
mechanical means. Jetting of native soils will not be acceptable.
8.12 Exterior Slabs and Walkways
► Subgrade Compaction
The subgrade below exterior slabs, sidewalks, driveways, patios, etc. should be compacted to
a minimum of90 percent relative compaction as determined by ASTM D 1557.
► 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.
► Slab Thickness
Concrete flatwork and driveways should be designed utilizing four-inch minimum thickness.
► 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.
► Flatwork Reinforcement
Consideration should be given to reinforcing any exterior flatwork.
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9.0
10.0
I 1.0
12.0
► 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.
BMP DESIGN
AGS conducted site specific percolation testing to determine preliminary infiltration rates and evaluate
feasibility fo r storm water infiltration at the project site. Testing was completed in general accordance
with the new 2016 San Diego Region BMP Design Manual. Worksheet C-4. l and supporting documents
are presented in Appendix D.
Based on the results of our preliminary testing, Full to Partial Infiltration design for BMPs is potentially
feasible for the Home Avenue portion of the site. For the Grand Avenue portion of the site AGS does
not recommend full or partial infiltration as this portion of the development will be supported by a
partially subterranean garage "Podium" structure. From a geotechnical perspective the addition of
shallow groundwater from infiltration near the podium structure is highly unpredictable. In some
instances infiltration below and adjacent to these types of structures has resulted in: additional hydraulic
forces on basement walls; increase the likelihood for unwanted seepage into the basement; caused
differential settlement across the basement floor; and created mounding of infiltration water due to the
disruption of the horizontal conductivity of the flat lying deposits found in the Old Paralic depos its.
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.
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 fi nal 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.
SLOPE AND LOT MAINTENANCE
Maintenance of improvements is essential to the long-term performance of structures and slopes. A (though the
design and construction during mass grading is planned to create slopes that are both grossly and surficially
ADVANCED GEOTECHNICAL SOLUTIONS, INC.
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Report No. J 607-03-B-2R2
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.
12.1. 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 should be made aware
that they are responsible for maintenance and cleaning of all drainage terraces, down drains and other
devices that have been installed to promote structure and slope stability.
12.2. Irrigation
The resident, homeowner and Homeowner Association should be advised of their responsibility to
maintain irrigation systems. Leaks should be repaired immediately. Sprinklers should be adjusted to
provide maximum uniform coverage with a minimum of water usage and overlap.
Overwatering 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.
12.3. Burrowing Animals
13.0
Residents or homeowners should undertake a program for the e limination of burrowing animals. This
should be an ongoing program in order to maintain slope stability.
LIMITATIONS
This report is based on the project as described and the information obtained from the excavations at the
approximate locations indicated on Plate 1. The findings are based on the res ults 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 and 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 a re-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.
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AGS has no respons ibility for construction means, methods, techniq ues, seque nces, or procedures, or for safety
precautions or programs in connection with the constructio n, for the acts or omissions of the CONTRACTO R,
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.
December 28, 2017
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REFERENCES
Page 20
Report No. I 607-03-B-2R2
Advanced Geotechnical Solutions, Inc. (2017), Revised Geotechnical Investigation and Foundation Design
Recommendations for Proposed Residential Multi-Family Podium Structure (800 Grand Ave.) and
Single Family (Home Ave.), 800 Grand Project, Carlsbad, Cali fornia(Report No. 1607-03-B-2R dated
11/21/17)
Advanced Geotechnical Solutions, Inc. (2017), Geotechnical Investigation and Foundation Design
Recommendations for Proposed Residential Multi-Family Podium Structure (Grand Ave.) and Single
Family (Home Ave.), 800 Grand Project, Carlsbad, California (Report No. 1607-03-8-2 dated
I 0/21/17)
American Concrete Institute, 2002, Building Code Requirements for Structural Concrete (ACI318M-02) and
Commentary (AC! 318RM-02), ACJ International, Farmington Hills, Michigan.
American Society for Testing and Materials (2008), Annual Book of ASTM Standards, Section 4, Construction,
Volume 04.08, Soil and Rock (I), ASTM International, West Conshohocken, Pennsylvania.
California Code of Regulation, Title 24, 2013 California Building Code, 3 Volumes.
California Emergency Management Agency, 2009, Tsunami Inundation Map for Emergency Planning, Point
Loma Quadrangle, County of San Diego, California, Scale I :24,000.
Gouvis Engineering 2017, 849 Home Avenue, Foundation Plans, Sheets SN-1,S 1.1 , S2. l, S3. l & SD-1, City
of Carlsbad, California dated November 22, 2017 (Job No. 64516)
Jennings, C. W., and Bryant, W.A., 2010, Fault Activity Map of California: California Geological Survey,
California Geologic Data Map No. 6, Scale I :750,000.
Kennedy, M.P., and Tan, S.S., 2008, Geologic Map of the San Diego 30' x 60' Quadrangle, California Regional
Geologic Map Series, Scale 1: I 00,000, Map No. 3, Sheet I of 2.
San Diego Region, Model BMP Design Manual for Permanent Site Design, Storm Water Treatment and Hydro-
modification Management, February 2016.
United States Geological Survey, 20 IO Ground Motion Parameter Calculator v. 5.1.0., World Wide Web,
http://earthquake.us gs.gov /designmaps/us/appl ication. php.
ADVANCED GEOTECHNICAL SOLUTIONS, INC.
APPENDIX A
FIELD AND LABO RA TORY DA TA
ADVANCED GEOTECHNICAL SOLUTIONS, INC., 2016
ADVANCED GEOTECHNICAL SOLUTIONS, INC.
~ '! ~AGS BORING NUMBER HS-1
PAGE 1 OF 1
ADVANCf.D GEDTECHNIC\l SOUfnO.'IIS. INC.
CLIENT McKellar McGowan PROJECT NAME 800 Grand Carlsbad
PROJECT NUMBER 1607-03 PROJECT LOCATION Carlsbad
DATE STARTED 9/10/16 COMPLETED 9/10/16 GROUND ELEVATION 62 ft HOLE SIZE 8 inch
DRILLING CONTRACTOR Baja Exploration GROUND WATER LEVELS:
DRILLING METHOD Hollow Stem Auger AT TIME OF DRILLING ---
LOGGED BY JAG CHECKED BY JAG AT END OF DRILLING ---
NOTES AFTER DRILLING ---
~ I-w ~ ~ ~ z (/) z a. (/) [ii' w* w I-0 :c (.) >-c:: c::~ z I-(/)
i== ~ :i: 0 (/) I-w :s: I-:::> t: ,;=-:::> I-0 z w I-~ (.) wCD 0 Z...J 1-Z i== O ~ I-<(,s: a..s: a.o MATERIAL DESCRIPTION z u >~ w ~ ~...J (/) ...1:::E ...1=>;:; :::>S (/)w ~ (.) ~ c:: :::> a.:::> CDO -I-w 0 o z (/) w ...J (:) :::E z (.) ~ >-:::> :c w <( c:: :::EO I-w I-(/) 0 (.) <( z 0 0 (/) ~
66t::l. n Artifical fill undocumented (afu)(\C approximately 2 inchr -with 3 inch of base -, a. t'.)
0 ... . ._§Q_ -@ 0.5 ft, Old Paralic Deposits 1Qop6)SIL TY
"' (/) _,
0: ... <.l
0 z ~ t'.)
~
9 g
~ <.l w 0 0: ~ ~ w ,= z w !!l (/)
!z w ::; ::, g
G :::; "' ::, a. u; 0: w (/)
;? 0
l-o t'.)
"' :5
(/) ::,
0 I-(/)
!z c3 ..,
~ g
"' <') >
t'.) 0 _,
t'.)
·Z a: 0 "' (/) ~
-
5
--
~ ...
_,_
--
10
--
~ ...
--
_,_
15
_,_
~ ... --
-1-
SANDSTONE, medium to fine grained, red brown, dry
@ 2.5 ft, slightly moist, freshening
@ 3.0 ft, SIL TY SANDSTONE, medium to fine grained,
slightly moist. moderately hard
@ 5.0 ft, SANDSTONE . medium to coarse grained, red to
brown, slightly moist, moderately hard to hard
@ 7.0 ft SANDSTONE, medium grained, light tan,
freshening
@ 14.0 ft SANDSTONE, medium to coarse grained, tan to
light brown, slightly moist, moderately hard, gravel 318th inch
h to 1/2 inch 1
@ 16.5 ft SANDSTONE, becoming saturated, interbedded
CLAY, very moist to saturated, hard
@ 19.0 ft, Santiago Formation (Tsa).CLAYSTONE, gray,
\ moist, moderately hard
@ 19.5 ft, CLAYSTONE, gray, moist to saturated, soft I
Total Depth = 19.75 Feet
No Groundwater Encountered
Backfilled with Cement and Bentonite Grout per San Diego
County
BU
Shear,
Remolded
Consol, El
,;; MC 36/3" 86 5.0 .:,near,
MC 50/3" Remolded
Consol
III SPT 15-18-21
(39)
III SPT 20-21-38
(59)
II SPT 21-32-5
(37)
-, a. (!)
0 < CD V, ...,
0: < (.)
0 z
;/i
(!)
~
$ ~ i;\ ... (.) w 0 0: ~ z ~ w i= z w 0 z w :; ::,
(.)
0 §
::;
CD ::, a. u5 0: w V, :2 t.l
.,
~ g
"' ~
(!) 0 ...,
(!) z er. 0 CD
V, ~
~ ~ ~AGS BORING NUMBER HS-2
PAGE 1 OF 1
AOVMICW GEOTl:CIINICAL SOLIJTIOIIIS. INC.
CLIENT McKellar McGowan PROJECT NAME 800 Grand Carlsbad
PROJECT NUMBER 1607-03 PROJECT LOCATION Carlsbad
DATE STARTED 9/10/16 COMPLETED 9/10/16 GROUND ELEVATION 64 ft HOLE SIZE 8 inch
DRILLING CONTRACTOR Baja Exploration GROUND WATER LEVELS:
DRILLING METHOD Hollow Stem Auger AT TIME OF DRILLING ---
LOGGED BY JAC CHECKED BY JAC AT END OF DRILLING ---
NOTES AFTER DRILLING ---
~ I-(/) w ~ w* z z Q. (/) w w I-0 (.) >-0:: 0:: ~ z I-(/)
~ ~ I :r: c., (/) 1-W s: I-=> !:: u =,I-0 z w I-~ (.) wCO 0Z...J 1-Z ~ 0~ I-~~ Q.""' a.o (/) MATERIAL DESCRIPTION ...J~ ....1::l~ z a. (/)w ~ (.) ~ 0:: w ~ ~...J ::i Q. ::i coo =>~ -1-w w 0 Oz (/) ...J <.'.) ~z (.) ~ >-~o ::i w I w <t: 0:: I-z I-(/) 0 (.) ~ u:: 0 0
l.lS.,.1U!UJ SM n Artificial Fill Undocumented {afu),0-4 inch CONCRETE 1 .... @ 4 inch, Old Paralic Deposits (Qop6)SANDSTONE, --SC medium to coarse grained, red brown, slightly moist, soft to
moderately hard .... @ 3.0 ft SIL TY SAND, medium to coarse grained, red
___§_Q__ brown, slightly moist, dense
@ 5.0 ft, SANDSTONE, medium to coarse grained, red
5 brown, moist, hard
@ 7.5 ft, medium to coarse grained, light tan, slightly moist,
MMC 21-31-39 119 4.3 31 --hard (70) @ 8.5 ft, CLAYSTONE, coarse grained, moist to very moist, .... soft to moderately hard ....
~-
10
@ 10.0 ft, SIL TY SANDSTONE, medium to fine grained, tan
lll sPT
12-14-14 --to red brown, moist to very moist, moderately hard (28) .... @ 12.0 ft, SIL TY SANDSTONE, medium to fine grained,
medium brown, moist to very moist, hard to very hard, (Tight --Drilling)
~ ...
15
@ 17.5 ft, SIL TY SANDSTONE, medium to fine grained, tan H MC 15-28 103 22.8 103 .... to gray, moist to very moist, hard -_MC 50/3" .... @18.0 ft, LAG DEPOSIT, coarse grained, very moist to
saturated, firm .....
~ ....
20
@ 20 ft, Santiago Formation (Tsa).CLA YSTONE, dark ~MC 5015" 108 18.9 99 ;:,near, ..... green, very moist to saturated, hard R~'.11olded onsol
Total Depth = 21.5 Feet
No Groundwater Encountered
Backfilled with Cement and Bentonite Grout per San Diego
County
.., a.. (!)
0 <(
CD (/) ..J a:: <( 0
0 z <( a:: (!)
§
M 9 ,_
lil (ii .... 0 w 0 a:: a.. ~ z 13 s: w ..J .... z w CD en ,-z w ::;; ::,
0 0 0 G ::::;
CD ::, a.. en a:: w (/) ;I
0
~
:!
~ ;::; ~
.... 0 (!)
CD s
(/) ::,
0 ,-
(/) ,-z 13 ..,
0 N g
"' M >
(!)
0 ..J
(!) z
ci: 0 CD Cl)
(!) <(
BORING NUMBER HS-3
AOVllNCfD GEOTECHNICAL SOLUTIONS, INC.
CLIENT McKellar McGowan
PROJECT NUMBER 1607-03
PROJECT NAME 800 Grand Carlsbad
PROJECT LOCATION Carlsbad
PAGE 1 OF 1
------------------------------------
DATES TARTED ~9~/~10~/ 1~6~---COMPLETED _9=/~10=/~16~---GROUND ELEVA TION~6~0~ft~--HOLE SIZE ~8~in=ch~-----
DRILLING CONTRACTOR_B_a~ja_E_x~pl_o_ra_ti_o_n _________ _ GROUND WATER LEVELS:
DRILLING METHOD --'H-'-o""l~loc..cwc..S=t=e~m~A--=--ug=e~r __________ _ AT TIME OF DRILLING_-_--_____________ _
LOGGED BY ~J~A~C _____ _ CHECKED BY ~J~A~C ___ _ AT END OF DRILLING_-_ •• _____________ _
NOTES ____________________ _ AFTER DRILLING_-_··----------------
z 0
i= ~ <(¢:: >-UJ ...J UJ
60
->-
->-
->-
->-
55
0 __u_
5
(/) u (/)
:)
SM
MATERIAL DESCRIPTION
~ Artificial Fill Undocumented (aful3 inch AC
@ 0.5 ft, Old Paralic Deposits (Qop6).SIL TY
SANDSTONE, medium to dark brown, slightly moist,
moderately hard
@ 1.0 ft SANDSTONE, medium to fine grained, red brown,
moist, moderately hard
Total Depth = 6.0 Feet
No Groundwater Encountered
Backfilled with Cement and Bentonite Grout per San Diego
County
UJ c.. >-a:: I-UJ
UJCO ...J:::i: c..:)
:::i:z <( (/)
~ w* (/) w a:: -s: I-:) !::: c-:) I-0Z-' zo 1-Z ...J:) <( :) .9, (/) UJ coo> -I-
u6 >-oz :::i:O a::
0 u
:,R 0
z 0 i=
c2
:)
I-<( (/)
I-z UJ I-z 0 :,R u ~
(/)
UJ z u::
(/) I-(/)
UJ l-a:: UJ J: l-o
-,
Q. (!)
0 <{ a, ~ Cl'. <{
<.)
0 z ~ (!)
§
q
~
05 l-o w 0 Cl'. ~ z ~ w .= z w ~ z w
::i; :::,
<.) 0 9 <.) :::; a, :::,
Q. u;
Cl'. w en ;? i.>
ti (!)
a, s en :::,
0 I-C/)
1-z 13 ..,
~ g
0,
M >
(!) g
(!) z ir 0 a,
en
(!)
<{
~ '! ~ACS BORING NUMBER HS-4
PAGE 1 OF 1
AD\IANC£D GEDTICIINICAL SOLUTIONS. INC.
CLIENT McKellar McGowan PROJECT NAME 800 Grand Carlsbad
PROJECT NUMBER 1607-03 PROJECT LOCATION Carlsbad
DATE STARTED 9/10/16 COMPLETED 9/10/16 GROUND ELEVATION 61 ft HOLE SIZE 8 inch
DRILLING CONTRACTOR Baja Exploration GROUNDWATER LEVELS:
DRILLING METHOD Hollow Stem Auger AT TIME OF DRILLING ---
LOGGED BY JAC CHECKED BY JAC AT END OF DRILLING ---
NOTES AFTER DRILLING ---
~ I-UJ g w~ ~ z Cl) z Q.
Cl) w UJ I-
0 u >-0:: 0:: -z I-Cl)
i=~ I :i:0 Cl) I-UJ s: I-:::, !:::'fi' :::, I-0 z UJ I-~ u wen 0Z...J 1-Z i= o;e I-<t:= Q. = Q. 0 MATERIAL DESCRIPTION >-w-~...J
Cl) ...J::i, ...J:::,~ z a. Cl) UJ ~ u ~ 0:: :::, Q.:::, cnO ::::>--1-UJ UJ Cl oz Cl) ...J ('.) ::i:z u~ >-::i:0 :::, UJ I UJ <t: 0:: I-I-
Cl) Cl u <t: z 0 0 Cl) u::
~ ... ~ SM -, Artifical Fill Undocumented jafu)~ inches AC over 3 ~
inches base
@ 0.25 ft SIL TY SAND, medium to fine grained. tan to red _,... brown, slightly moist, dense
-1-@ 0.5 ft Old Paralic Deposit (Qop6) SANDSTONE
--l medium to fine grained, red brown, slightly moist,
moderately hard r 5 @ 5.0 ft SANDSTONE, medium to coarse grained, light tan
~-to red brown, slightly moist, hard
IIISPT 12-11-12 Sieve @ 6.0 ft SANDSTONE, medium to fine grained, light tan, (23)
_,... slightly moist, moderately hard
----
10
,.2Q__ @ 10.0 ft SANDSTONE, medium grained, dark brown,
MMC 23-47-50 117 7.6 51 23 slightly moist, soft (97) @ 12.0 ft SANDSTONE, medium to fine grained, brown to _,... dark brown, moist, moderately hard to hard
(hard drilling)
@ 13.0 ft occasional 4 inch gravel
-
-1.L
~ @ 15.0 ft lnterbedded SAND, medium to fine grained, tan to
II l sPT 12-12-20 gray brown, saturated, dense (32)
-1-
@ 17.5 ft LAG Deposit, 3/8th-3/4th inch diameter
-@ 18.0 ft, Santiago Formation (Tsa)SANDSTONE,
-medium to coarse grained, saturated, very hard ~ MC 24 109 20.5 108
I MC 50/2" 20
Total Depth= 20.0 Feet
No Groundwater Encountered
Backfilled with Cement and Bentonite Grout per San Diego
County
BORING NUMBER TB-1
PAGE 1 OF 1
ADVANCCD GEOTECHNICAL SOLUTIONS, INC.
CLIENT McKellar McGowan PROJECT NAME 800 Grand Carlsbad
PROJECTNUMBER_1~6=0~7-~0~3 ____________ _ PROJECT LOCATION_C=a=r~ls~b=ad~--------------
DATE STARTED 9/10/16 COMPLETED 9/10/16 GROUND ELEVATION 66 ft HOLE SIZE 6 inch --------------------------
DRILLING CONTRACTOR-'N~a=t~iv~e-'D=r~ill~in~g~----------GROUND WATER LEVELS:
AT TIME OF DRILLING ---DRILLING METHOD_T_r~ip~1o_d _____________ _ ----------------
LOGGED BY -'F--=E=-------CHECKED BY -'J"'"A""'C'-----AT END OF DRILLING_-_--_____________ _
NOTES ____________________ _ AFTER DRILLING_-_--______________ _
"' 9
z 0
i='.~ <( ¢: >~
UJ ..J UJ
~'" en .... u w 0 Q'. a. ~ ~ w ;= z UJ ~ ~ w
..M....-
-
--
:r: t-~ c.. ¢: UJ ~
0
0
-
-
-
-
-
-
-
-
-
Cl)
(.)
Cl)
::::)
SM
MATERIAL DESCRIPTION
Artificial Fill Undocumented (afulSIL TY SAND, medium
r'. grained, brown, dry, loose, some rootlets ,
@ 1 ft Old Paralic Deposits (Qop6lCLAYEY
SANDSTONE, fine grained, reddish brown, slightly moist,
moderately soft, some silt
@ 4 ft SIL TY SANDSTONE, fine grained, reddish brown.
moist to slightly moist, soft, trace olive mottling, trace clay
@ 5.0 ft CLAYEY SANDSTONE, fine grained, reddish
yellow and light yellowish brown, slightly moist to moist,
moderately hard, some olive mottling
@ 8.0 ft CLAYEY SANDSTONE, fine grained, pale olive,
moist, moderately hard, some silt
_,.....!L
50 ~ @ 14.0 ft SANDSTONE, fine to coarse grained, yellowish 81--=-=--....__......__.....,_ __ ......._,\ brown and light olive, saturated, moderately soft, friable, / 3 ._t_ra_ce_s_il_t ________________ __,
iil Total Depth= 16.0 Feet
~ Saturated at 14.0 ft
lQ Backfilled with Cement and Bentonite Grout per San Diego
~ Cou~y
;I u
..,.
~ g
"' ~
8 ...J
'-' z ir 0 al
(/)
'-'
UJ c.. >-Q'. 1-UJ
UJCD
..J :::!! c..::::)
:::i!z <(
Cl)
~MC
=-. MC
~MC
~MC
-=s,MC
~Mc
(/) w ~ I-:) 0z...1
..J::::)~ coo (.) 6
18-32
30/4"
8-11-14
(25)
22-33
30/3"
22-33
50/5"
~ ~ w* ~
Q'. ~ z
t:: 'i3 ::::) I-0
1-Z i='. z a. (/)UJ ~ ::::)~ -1->-Oz ::::) Q'. :::i!O I-0 (.) <( Cl)
123 6.0 49
110 8.3 45
120 9.6 72
108 19.6 101
I-z
UJ I-z
0 ~ (.) ~
Cl)
UJ z u:::
Cl)
1-(/)
UJ l-
a:: UJ :r: 6
Shear,
Remolded
Consol
<C L-.----------------------------------------------------'
AOVANCW GEOTlCIINICAl SOUJTIONS, INC.
CLIENT McKellar McGowan
PROJECT NUMBER_1c...=6=0-'---7---=0-=-3 ____________ _
DATESTARTED~9~/-'---10~/1-'---6~---COMPLETED ~9_/1~0_/1~6 __ _
DRILLING CONTRACTOR----'N--"a=ctc..civ--=e--=D"--'r-"'illc.cin"'g'------------
DRILLING METHOD_T-'---r~io--=o=d _____________ _
LOGGED BY FE --------CHECKED BY ----'J"--A'""C'------
NOTES ____________________ _
z 0
j:: ~
<( = >~ w __J
w
J: r ~
ll. = w ~
0
0
(/)
(.)
(/)
:)
MATERIAL DESCRIPTION
BORING NUMBER TB-2
PAGE 1 OF 1
PROJECT NAME 800 Grand Carlsbad
PROJECT LOCATION_C-=-a=r~ls=b=ad~--------------
GROUND ELEVATION_6~1_ft~--
GROUND WATER LEVELS:
AT TIME OF DRILLING ---
HOLE SIZE _6_in~ch _____ _
----------------
AT END OF DRILLING_-_--______________ _
AFTER DRILLING ---------------------
w ~ ll. (/) w >-a:: f-W 31: r :J t::::,;:-wai oz__J zo __J~ __J:) ~ :) -9, ll.:) aiO ~z (.) ~ >-<( a::
(/) 0
~
UJ ~ 0
z a::~ :Jr 0
t-Z j:: (/)w ~ -r oz :) ~o r (.) <(
(/)
r z w r z
0 ~ (.) ~
(/) w z u::
(/) r (/) w r a:: w J:
5
-
SM \ TOPSOIL SIL TY SAND, fine grained, brown, slightly t moist, loose, abundant roots
ci ~ -@ 0.5 ft Old Paralic Deposits (Qop6}SIL TY
SANDSTONE, yellowish red, slightly moist, soft, moderately ~ MC 10-15-22 .. a,
(/) I---..J a: .. 112 5.3 31 weathered, roots to 3 ft (37) @ 3.5 ft moderately hard, less weathered u ~ -
0
~I--_L
~~--
"' ~ 9 ..... lil I--
i1i --
@ 4.0 ft SIL TY SANDSTONE, fine grained, reddish brown, ~ MC
15-21-22 .:,near,
slightly moist, moderately hard, trace clay, roots to 6ft (43) 108 4.9 25 Remolded
@ 5.0 ft SANDSTONE, fine grained, light yellowish brown to Consol Consol
reddish yellow, dry to slightly moist, moderately hard, some
silt, friable
I---~ 0 UJ ..,
0 a: a. 50 ~ z <3 ►
u MC 13-18-22 108 4.5 23
Total Depth = 11.0 Feet , (40)
No Groundwater Encountered UJ ..J I---Backfilled with Cement and Bentonite Grout per San Diego
z UJ County
~ I---z UJ :::; :::,
<..)
0 0
G :::; a, :::,
9, (/) a: UJ (/)
;:i u
~ v
~ ;:;
0
,-'..
0 (!)
a,
'.5
(/) :::,
0 I---(/)
I---z <3 ...
~
0 "' "' "' > (!) 0 ..J
(!) z ii: 0 a,
(/) (!) ..
Advanced Geotechnical Solutions, Inc.
MOISTURE CONTENT / DRY DENSIT' ( INTACT SAMPLES)
D-2216, D1557
EXCAVATION TB-I TB-I TB-I TB-I
DEPTH 2' 5' 10' 15 '
SOIL Redish Redish Redish Light
Brown Brown Brown Brown
Silty Sand Silty Sand Silty Sand Fine to
Coarse
Sand
LENGTH 6 5 5 5
TUBE+W. SOIL 1222.7 945.2 1025.9 1007.5
TUBE 267.9 223.3 223.3 223.3
W. SOIL 954.8 721.9 802.6 784.2
FACTOR 0.01609 0.01 34 1 0.0 134 1 0.0 1341
W. DENSITY 130.71 118.57 13 1.83 128.81
CUP NO. 75 68 86 71
CUP+W. SOIL 326.64 279.67 25 1.38 285.15
CUP+D. SOIL 308.61 258.92 230.03 239.69
MOIST. LOSS 18.03 20.75 21.35 45.46
CUP 8.26 8.40 8.24 8.01
D. SOIL 300.35 250.52 22 1.79 23 1.68
MOIST. CO NT. 6.00 8.28 9.63 19.62
DRY DENSITY 123.31 109.50 120.25 107.68
DEG. SATUR. 44 42 65 94
EXCAVATION HS-I HS-2 HS-2 HS-2
DEPTH 5 ' 5 ' 15 ' 20'
SOIL Redish Redish Light to Light Gray
Brown Brown Dark Gray Silty Fine
Silty Fine Silty Fine Sand Sand
Sand Sand
LENGTH 4 6 6 6
TUBE+W. SOIL 774.7 11 75.2 1193.3 1209.3
TUBE 223.3 267.9 267.9 267.9
W. SOIL 551.4 907.3 925.4 941.4
FACTOR 0.01341 0.01 609 0.0 1609 0.01 609
W. DENSITY 90.57 124.20 126.68 128.87
CUP NO. 68 75 88 76
CUP+W. SOIL 199.56 322.25 305.39 180.32
CUP+D. SOIL 190.49 309.40 250.24 152.96
MOIST. LOSS 9.07 12.85 55.15 27.36
CUP 8.48 8.34 8.13 8.06
D. SOIL 182.01 301 .06 242.11 144.90
MOIST. CONT. 4.98 4.27 22.78 18.88
DRY DENSITY 86.27 119.12 103.18 108.40
DEG. SATUR. 14 28 97 92
PROJECT 800 Grand ------------FILE NO. 1607-03
BY H-M DATE 9/12/20 I 6
TB-2 TB-2 TB-2
2' 5' 10'
Redish Redish Medium
Brown Brown Brown
Silty Fine Silty Fine Sand
Sand Sand
4 5 6
752.9 9 15.3 1090.0
178.6 223.3 267.9
574.3 692.0 822.1
0.0 I 073 0.01 341 0.01 609
11 7.91 11 3.66 112.54
3 71 86
260.80 123.45 275.21
248.15 118.10 263.72
12.65 5.35 11 .49
8.03 8.03 8.34
240.12 I 10.07 255.38
5.27 4.86 4.50
112.01 108.40 107.70
28 24 22
HS-4 HS-4
IO' 18.5 '
Dark Olive Gray
Brown Sand Some
Silty Sand Silt Stone
6 6
11 86.9 1225.1
267.9 267.9
919.0 957.2
0.01609 0.0 1609
125.81 131.04
93 4
290.57 322.45
270.66 269.02
19.91 53.43
8.24 8.18
262.42 260.84
7.59 20.48
116.93 108.76
46 IOI
ADVANCED GEOTECHNICAL SOLUTIONS, INC.
CONSOLIDATION -ASTM D2435
Project Name: 800 Grand ---------Excavation: TB-2
Location: ---------Depth: 5'
Project No: _1_6_07_-_0_3 _____ _
Date: 9/13/2016
Description: __ S_i_,,_lty_F_in_e_S_a_n_d __
By: __ H_M __
-~ -~
C:
0 .. cu "C
0 II)
C: 0 (.)
0.1
1
0 =-•-
-1
-2
-3
-4
i=•
-5
-6
-7
Test Description:
Water Content, w
Void Ratio, e
Saturation, S
Dry Density (pcf
Wet Density (pct)
.,..
*
Consolidation-Pressure Curve
Normal Pressure (ksf)
1 10
-
~
~ --~
.,
* '
* * ~
Before Test After Test
4.9% 17.5%
0.65 0.60
20% 78%
102.3 105.0
107.2 123.4
100
ADV ACED GEOTECHNICAL SOLUTION . INC .
EXPANSION INDEX TEST ASTM (04829)
Project Name: __ 8:..;0--0_;G __ ra;;;.;.n.;.;.d ______ _ Excavation: HS-1 ---------Location: Depth: 2-5' ----------File No: 1607-03 ----..:.....;_;~=---------Description: _Si~lty._S_a_n_d ____ _
Date ----------SAMPLE PREPARATION Bv: H-M
PARAMETER FORMULA UNITS DATA
Ring Volume A cf 0.007268
Specific Surcharqe osf 144
2-lb Sample Moist B % 7.3
Wt. Rinq C Q 194.4
Wt. Ring + Wet Soil D g 619.4
Wt. Wet Soil E = D -C Q 425
Dry Density F pcf 120.04
Initial Saturation G = (8 x 2.7 x F) / (2.7 x 62.4 -F) % 49
FINAL SAMPLE INFORMATION
Wt. Rinq + Tare + Wet Soil H Q 733.5
Wt. Ring+ Tare+ Dry Soil I g 677.2
Tare J no. 19
Wt. Tare K a 98.8
Wt. Moisture Loss L = H -I Q 56.3
Wt. Orv Soil M=I -C-K Q 384
Final Moisture Content N = 100 x (LI M) % 14.7
Final Saturation 0 = (N X 2.7 X F) / (2 .7 X 62.4 -F) % 98.09
Rinq Volume After Test P = (R -S + 1) x 0. 08722 I 12 cf 0.00735
TEST INFORMATION
PROPOSED READINGS FORMULA DATE TIME UNITS
LOAD APPLIED
0 minute Q 9/15/2016 12.30 PM 0.5431
10 minute R 9/15/2016 12.40 PM 0.5409
11 minute WATER ADDED
s 9/16/2016 1.00 PM 0.5527
EXPANSION INDEX El = 1000 x (S -R) 12 Low
INITIAL INITIAL INITIAL FINAL FINAL FINAL
DRY MOISTURE SATURA-SWELL EXPANSION DRY MOISTURE SATURA-
DENSITY CONTENT TION (%) INDEX DENSITY CONTENT TION
\C:l,l"+v"+)I
F (pct) B (%) G (%) El /10 (El) (100+N)x10 N (%) 0 (%)
n
120.04 7.3 48.8 1.2 12 118.63 14.7 98.1
Advanced Geotechnical Solutions, Inc.
MAXIMUM DENSITY
ASTM D-1557
Project Name: 800 Grand ---------Location: ---------
Excavation: HS-1
Depth 2-5'
Fi I e No: 1607-03 Description: Dark Brown Silty Sand
Date: 9/17/2016
Sieve Size
Mold Size
No. of Layers
Test point number
Wt. wet soil + mold
Wt. wet soil + mold
Wt. of mold
Wt. wet of soil
Wet density
Dry density
4
4"
5
Q
lbs
lbs
lbs
ocf
pcf
Moisture Determination (Oven)
Container number
Wt. wet of soil+tare a
Dry wt. soil+tare a
Tare wt. I a
Wt. of moisture a
Dry wt. of soil Q
Moisture Content a
140.0
135.0 --
130.0 ---
C
1
3986.3
8.78
4.10
4.68
140.41
132.24
12
264.5
249.61
8.62
14.89
240.99
6.18
% Retained None ----Method A ----By:
2 3 4
4053.1 4072.7 4051 .2
8.93 8.97 8.92
4.10 4.10 4.10
4.83 4.87 4.82
144.83 146.12 144.70
134.79 134.44 130.50
71 8 3
282.3 266.3 285.4
263.3 245.7 258.2
8.24 8.55 8.24
19.00 20.60 27.20
255.06 237.15 249.96
7.45 8.69 10.88
Max Density
I
I .
Zero Air Voids Curves
-.. .. .. .. .. .. ,.. .. .. ..
H-M ----
--(.) 125.0 --C.
~
-,-
t-+--+---,1---J+-. _-.I,+_-_.-+--,-+--+--+-¼--1!--+--::i-.,-+1'-~--"~'--+---l---+-
.. .. ~,--~,-~c.t,.=-~;-.:<t-~.t~J-c.:}-c.:<r~.t~..t~.ta=-.:<+~.t~..t~.:}-i=-~
Ill
C
Cl)
0
~
0
120.0 ..... --,.---:-·---'-~"-~:•"""""lr--•,~~-:~~-t=:t=j==t==t=!=j=jt==t=:t=:!=jt=t··=:t='::t:..~ .... 1~+-,J--.J..-=.~
9"Z=9S ---
I .... "
11 5.0 ---1-__i_1_,:----:•-.--i"'llli,. -~'--t-+--+---+--+--.--+--1!--+--+--f--+--+--+,-+--l!--P...,.<-+-~J_.....;!!-i.:' -. .... -_ ➔ .. -_ --l_j-_ -_+-I--_+..,.-_ ....... -_ --l_J-_ -_+-I--_+..,.-_➔ .. -_ -1 ....
.... ¢~_--+---i-1--+--+--+--+--+--+-I
110.0 -------------
I -....._
105.0 ·--,-,--•-•---,-:-:-•---,-I-
5.0 10.0
Maximum Density 135.0 pct
I I
15.0
Moisture%
20.0
-.... ..
25.0
Optimum Moisture _ ___;;8-'-.0"--_%
30.0
Samples Tested 1 2
Boring ID HS-1 HS-1
Depth (in/ft.) 2-5' 2-5'
Initial Dry Density (pcf) 121.5 121.5
Initial Moisture Content(%) 8.00 8.00
Normal Stress (psf) 1000 2000
Maximum Shear Stress (psf) 1087 1802
Ultimate Shear Stress (psf) 963 1647
ASTM D3080
Vertical Deformation v. Displacement
0.06
0.05
0.04
:[ 0.03
C ~ 0.02
"' ~ ~ 0.01
QJ C --.. -----
iv 0.00 u . -i ,~~
QJ > -0.01
-0.02 ':'" -1000
-e-2000
-0.03 ... -6-4000
-0.04
0.00 0.05 0.10 0.15 0.20 0.25
Displacement (in)
4000
3500
3000
i;:-2500 Ill a.
Ill Ill C1I
3
HS-1
2-5'
121.5
8.00
4000
3169
3169
3500
3000
2500
(;:' "' ~ 2000
~ vi ... 1500 "' QJ .r. VI
1000 -
500
0 0.30 0.00
Shear Stress
Peak Ultim.
Friction Angle, phi (Deg)l1----3_5t __ 3_6-1l
Cohesion ( psf) ..... __ 4_0_0.._ __ 2_0__,0
Sample Type: Remolded -----------
Strain Rat e (in/min): 0.005
Shear Stress v. Displacement
-1000
-e-2000
-6-4000
0.05 0.10 0.15 0.20 0.25 0.:
Displacement {In}
_,,,,)]
/ ~
/
v/
2000 ... ... VI ...
l'O ~ ~ a, .r:. 1500 VI
1000
500
~ V
~ 0 Peak
/ 1/~ D Ultimate
1/
0
0 500 1000 1500 2000 2500 3000 3500 Normal Stress (psf)
4000 4500 5000 5500 600
800 Gra nd, Remolded
Samples Tested 1 2 3 Peak Ultim.
Boring ID HS-1 HS-1 HS-1
Depth (in/ft.) 5' 5' 5'
Friction Angle, phi (Deg)~ ___ 3_8t __ 3_8--1I
Cohesion (psf)L.. ___ 23_o ...... __ 23_o .....
Initial Dry Density (pcf) 99.74 98.86 105.13
Initial Moisture Content (%) 4.98 4.98 4.98 Sa mple Type: Remolded -----------
Normal Stress (psf) 1000 2000 4000
Maximum Shear Stress (psf) 901 1957 3293
Ultimate Shear Stress (psf) 901 1957 3293
ASTM D3080 Strain Rate (in/min): 0.005
Vertical Deformation v. Displacement Shear Stress v. Displacement
0.06 3500 -1000
0.05 -e-2000
3000 --.!,-4000
0.04
I 0.03 2500
C .g 0.02
"' § 0.01 -2 .,
C
;;; 0.00 u "f ., -0.01 >
---
-~ --= =~ -~
~ "' °;' 2000
"' ~ "' ... 1500 "' .,
.s::: "'
1000
-0.02 -1000
-0.03
-e-2000 .... --.!,-4000
500
-O.Q4 0
0.00 0.05 0.10 0.15 0.20 0.25 0.30 0.00 0.05 0.10 0.15 0.20 0.25 0.,
Displacement (in) Displacement (in)
Shear Stress
4000
3500
3000
C' 2500 "' Q.
"' "' Cl.I 2000 ... .. ll'l
/l /v
V / 1'1/ ... IV Cl.I .c 1500 ll'l
1000
/
I/ V
0 Peak /[~ D Ultimate
500 ./
/
0
0 500 1000 1500 2000 2500 3000 3500
Normal Stress (psf)
4000 4500 5000 5500 God
800 Grand, Intact
Samples Tested 1 2
Boring ID HS-2 HS-2
Depth (in/ft.) 20' 20'
Initial Dry Density (pcf) 99.09 105.9
Initial Moisture Content(%) 18.88 18.88
Normal Stress (psf) 1000 2000
Maximum Shear Stress (psf) 994 1740
Ultimate Shear Stress (psf) 963 1S54
ASTM D3080
Vertical Deformation v. Displacement
I
C ~ .. E ~ .. C
iv u t: .. >
0.06
0.05
0.04
0.03
0.02
0.01
0.00 -
-0.01
-0.02
-0.03 ~
-0.04
0.00
4000
3500
3000
~ 2500 Ill
E:
Ill Ill
~
""'--
--
-1000
-2000
-b-4000
0.05 0.10 0.15 0.20 0.25
Displacement (in)
3 Peak Ultim.
HS-2
20'
Friction Angle, phi (Deg), ____ 3_6t __ 3_6--11
Cohesion (psf)~. ___ 28_0~ __ 1_5~0
98.51
18.88 Sample Type: Remolded -----------4000
3169
3169
Strain Rate (in/min): 0.005
Shear Stress v. Displacement
3500 -1000
-e-2000
3000
2500
c;:-"' -; 2000
"' t Ill
~ 1500 .. .. .r. Ill
1000
500
0 0.30 0.00 0.05 0.10 0.15 0.20 0.25 0.;
Displacement (in)
Shear Stress
~]
/ V
// /
~ 2000 ... VI .. "' CII /4 ~
.s:. 1500 VI
1000
500
~ ~
~ ·v
/
~
0
0 500 1000 1500
,
2000 2500 3000 3500 Normal Stress (psf)
4000 4500
800 Grand, Intact
0
D
5000
Peak
Ultimate
5500 God I
Samples Tested 1 2
Boring ID TB-1 TB-1
Depth (in/ft.) 10' 10'
Initial Dry Density (pcf) 109.29 127.88
Initial Moisture Content(%) 9.63 9.63
Normal Stress (psf) 1000 2000
Maximum Shear Stress (psf) 1181 3418
Ultimate Shear Stress (psf) 621 1616
ASTM D3080
Vertical Deformation v. Displacement
0.06
0.05
0.04
I 0.03
C 0 0.02 . ., .. E O.Ql .2 .. C
ii 0.00 u "f .. > -0.01
3
TB-1
10'
112.5
9.63
4000
2796
2579
Peak Ultim.
Friction Angle, phi (Deg) ~ ___ 2_3t __ 3_2...;I
Cohesion ( psf) ..... __ 14_9_0-'-__ 1_4__,~
Sample Type: Remolded -----------
Strain Rate (in/min): 0.005
Shear Stress v. Displacement
4000 --1000
-2000
3500 -11--4000 ------------~
~ 2500 -l:--------,,f....,t£.:.._ _ _!!l_:.:~~~L-_j
~ .. ~ 2000 --1------,__ ______ ....,__ ____ -""1 .;; . ... .. .. ~ 1500 -l---~IL---------------l
-0.Q2 -1000 ____________ _,
--e-2000
-0.03 -11--4000
-0.04
0.00 0.05 0.10 0.15 0.20 0.25 0.30 0.00 0.05 0.10 0.15 0.20 0.25 0.,
Displacement (in) Displacement (in)
Shear Stress
4000
3500 (~
__..,....
3000
;;::-2500 .,, .e .,, .,,
QI 2000 .. ... VI .. ro QI ..c 1500 VI
1000
500
~ ~ ,~
_/1b
L..-----' V ~ V --~ ......... V __..,....-lb /
V V
1D 0 Peak
/ v □ Ultimate ~ 0
V
0
0 500 1000 1500 2000 2500 3000 3500
Normal Stress (psf)
4000 4500 5000 5500 God
800 Grand, Intact
Samples Tested 1 2 3 Peak Ultim.
Boring ID TB-2 TB-2 TB-2
Depth (in/ft.) 5' 5' 5'
Friction Angle, phi (Deg)~ ___ 3_2t __ 3_4--ll
Cohesion ( psf) L... __ s_o_o..1.. __ 2_1_,s
Initial Dry Density (pcf) 102.95 101 105.76
Initial M oisture Content (%) 4.86 4.86 4.86 Sample Type: Remolded -----------Normal Stress (psf) 1000 2000 4000
Maximum Shear Stress (psf) 994 1926 2921
Ultimate Shear Stress (psf) 777 1771 2890
ASTM D3080 Strain Rate (in/min): 0.005
Vertical Deformation v. Displacement Shear Stress v. Displacement
0.06 3500 -1000
0.05 -2000
3000 · ---b-4000
0.04
I 0.03 2500
C ~ 0.02 .. E 0.01 2 QI 0
ni 0.00 ~
,;:-.,,
-;' 2000 .,,
f ~ ... 1500 .. QI J:; "' ~ -0.01 1000
-0.02 -1000
-2000
-0.03 ---b-4000
500
-0.04 0
0.00 0.05 0.10 0.15 0.20 0.25 0.30 0.00 0.05 0.10 0.15 0.20 0.25 0.,
Displacement (in) Displacement (in)
Shear Stress
4000
3500
3000
i;:-2500 "' .e
"' "' CII 2000 .. .. "" ..
111 CII .c 1500 ""
1000
500
~
v ~
0 ~
~ ~v
~ V
/. 0 Peak
1/' 1/
/ ] D Ultimate
:/
0
0 500 1000 1500 2000 2500 3000 3500 Normal Stress (psf)
4000 4500 5000 5500 God
800 Grand, Intact
ADVANCED GEOTECHNICAL SOLUTIONS, INC.
PARTICLE SIZE ANALYSIS -ASTM 0422
Project Name: 800 Grand --------Excavation: HS-4 --------Location: 0 --------Depth: _5_' ______ _
Project No.: 1607-03 --------By: HM
Date: 6/17/16
Cobbles C. Gravel F. Gravel c. Sand Md. Sand F. Sand Silt Clay
100
90
80
70
*
60
Ill) so C ·;;;
"' RI 40 n. ... C OJ 30 u ... OJ n. 20
i I ,
I I I N J I
I I I l I 11 I 11
1
I
I I I I i
11 I ! I I l 1~ I ----i
I I
7
I I I
l1 I I I ~ I I ,,
I I I
I
11 31 \
1 1 1· \ I I I I I
11
I I I I \ IT \
I '\. I
-
I
-,:I-,.., I ~ ~;,.
10 ~
0 I I
1000 100 10 1 0.1 0.01 0.001
Grain Size (mm)
Grain Size Grain Size Amount
(in/#) (mm) Passing (%) Summary
3" 76.20 % Gravel = 0.0
2 1/2" 63.50 % Sand= 76.8
2" 50.80 % Fines = 23.2
1 1/2" 38.10 Sum= 100.0
1 " 25.40
3/4" 19.05
1/2" 12.70 LL= ----3/8" 9.53 PL= ----#4 4.75 Pl= ----#10 2.00 100.00
#20 0.85 #NIA
#30 0.60 #N/A Soil Type: ___ _
#40 0.425 81 .86
#50 0.30 #N/A
#60 0.212 #N/A
# 100 0.15 31 .85
#200 0.075 23.21
Hydro 0.0319 18.68
Hydro 0.0204 17.34
Hydro 0.0100 16.01
Hydro 0.0084 14.67
Hydro 0.0060 12.01
Hydro 0.0030 10.67
Hvdro 0.0013 9.34
LABORATORY R E P O R T
Telephone (619) 425-1993 Fax 425-7917 Established 1928
CLARKSON LABORATORY AND SUPPLY INC.
350 Trousdale Dr . Chula Vista, Ca . 91910 www.clarksonlab .com
A N A L Y T I C A L A N D C O N S U L T I N G C H E M I S T S
Date: September 30, 2016
Purchase Order Number: 1607-03
Sales Order Number: 32907
Account Number: ADVG
To: *-------------------------------------------------*
Advance Geotechnical Solutions Inc
9707 Waples Street Ste. 150
San Diego, CA 92121
Attention: Paul Deresi
Laboratory Number : SO6150 Customers Phone: 850-3980
Sample Designation: *-------------------------------------------------*
One soil sample received on 09/23/16 at 1 :05pm,
from Project# 1607-03 marked as HS-1@ 2-3 ft .
Analysis By California Test 643, 1999, Department of Transportation
Division of Construction, Method for Estimating the Service Life of
Steel Culverts.
pH 7.5
Water Added (ml)
37
48
67
85
104
10
5
5
5
5
5
5
5
5
years
years
years
years
years
to perforation
to perforation
to perforation
to perforation
to perforation
for a
for a
for a
for a
for a
Water Soluble Sulfate Calif.
Water Soluble
Rosa M. Bernal
RMB/ilv
Chloride Calif.
16 gauge metal
14 gauge metal
12 gauge metal
10 gauge metal
8 gauge metal
Test 417
Test 422
Resistivity (ohm-cm)
5700
2800
2100
1800
1700
1700
1600
1900
2200
culvert.
culvert.
culvert .
culvert .
culvert.
0.003% (30ppm)
0.010% (96ppm)
APPENDIXB
GENERAL EARTHWORK SPECIFICATIONS
AND GRADING GUIDELINES
ADVANCED GEOTECHNICAL SOLUTIONS, INC.
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. Recommendations
provided herein and in the geotechnical report may need to be modified depending on the conditions
encountered during grading.
B. The contractor is respons ible 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 stricter requirements shall govern.
C. lt is the contractor's responsibility to read and understand the guidelines presented herein and in the
geotechnical report as well as the project plans and specifications. In formation presented in the
geotechnical report is subject to verification 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 perform 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 the responsibility to provide 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. Prior to the start of grading, a qualified Geotechnical Consultant should be employed to observe
grading procedures and provide testing of the fill s 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 prior to placing fill. It is the contractor's responsibility to apprise the Geotechnical Consultant
of their schedules and notify the Geotechnical Consultant when 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.
II. Site Preparation
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.
B. Unsuitable Soils Removals: Earth materials that are deemed unsuitable for the support of fill shall be
removed as necessary to the satisfaction of the Geotechnical Consultant.
ADVANCED GEOTECHNICAL SOLUTIONS, INC.
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 project requirements and tested as specified.
E. All areas receiving fill shall be observed and approved by the Geotechnical Consultant prior 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, derived 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 deleterious 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 materials 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 fi ll 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 in thin, 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 geotechnical 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. If the moisture content is above the limits specified by the Geotechnical Consultant,
the fill materials shall be aerated by discing, blading, or other methods until the moisture content is
acceptable.
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 dry density as
determined by ASTM Test Method: DI 557-09.
ADVANCED GEOTECHNICAL SOLUTIONS, INC.
G. Benching: Where placing fill on a s lope exceeding a ratio of 5 to 1 (horizontal to vertical), the ground
s hould 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 materials, or as
recommended by the geotechnical 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 J /2 the height of the fill
slope.
H. Slope Face: The specified minimum relative compaction shall be maintained out to the fini sh 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 overbuilding may vary as field conditions dictate.
Alternately, this may be achi eved 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 I (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
overexcavation is needed.
K. Fill materials shall not be placed, spread, or compacted during unfavorable weather conditions. When
grading is interrupted by rain, fil ing operations shall not resume until the Geotechnical Consultant
approves the moisture and density of the previous ly placed compacted fill.
IV. Cut Slopes
A. The Geotechnical Consultant shall inspect all cut slopes, including fill over cut slopes, and shall be
notified by the contractor when cut slopes are started.
8 . 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 sha ll not be excavated higher or steeper
than the requirements of the local governing agencies. Short-tenn 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
recommendations of the Geotechnical Consultant. The location of subdrains, especially outlets, shall be
surveyed and recorded by the Civil Engineer.
B. Top-of-slope Drainage: Positive drainage shall be established away from the top of slope. Site drainage
shall not be pennitted to flow over the tops of slopes.
ADVANCED GEOTECHNICAL SOLUTIONS, INC.
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-erodible interceptor swales shall be placed at the top of cut slopes that face the same direction as
the prevailing drainage.
VI. Erosion Control
A. All finish cut and fill slopes shall be protected from erosion and/or planted in 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. During 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 fo llowing 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 req uire further evaluation by the Geotechnical Consultant. If a contractor fails to
provide safe access for compaction testing, backfill not tested due to safety concerns may be 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 densified by jetting.
C. Backfill: Jetting of backfill materials is generally not acceptable. Where permitted by the Geotechnical
Consultant, the bedding materials can be densifi ed by jetting provided the backfill materials are granular,
free-draining and have a Sand Equivalent greater than 30.
VIII. Geotechnical Observation and Testing During Grading
A. Compaction Testing: 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 tests indicate 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 unsatisfactory
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.
C. 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 sha ll notify the contractor,
and the contractor shall rectify the conditions, and if necessary, stop work until conditions are
satisfactory.
ADVANCED GEOTECHNICAL SOLUTIONS, INC.
D. 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 fi ll materials placed.
E. 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.
F. 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 Geotechnical Consultant.
G. 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.
H. Reporting of Test Results: After completion of grading operations, the Geotechnical Consu ltant shall
submit reports documenting their observations during construction and test results. These reports may be
subject to review by the local governing agencies.
ADVANCED GEOTECHNICAL SOLUTIONS, INC.
DESIGN GRADE
.. --SUITABLE
;';~ ''?~'•/1>~,?<_'-t/.: / • • • ♦ A /~.f_.),~~,',(%,-(.((;)'~
~,, ~~·,,.:>,.,,'-/,•/,} •.• • • •; ':l,),j,,,~,·~ '>'., BEARING MATERIAL
~ ... ;•.'
SUBDRAIN OPTION 1 OR 2 ; ·::.d·I~ PLACE SUBDRAIN AT LOWEST
(SEE DETAIL 2) .• ·,.~.:v:· GRADE WITHIN CANYON REMOVAL .•)<,~~~¢
CANYON SUBDRAIN PROFILE
DIRECT SOLID OUTLET PIPE TO
APPROVED DRAINAGE AREA PER
PROJECT CIVIL ENGINEER
CONSTRUCT DRAIN OUTLET
CUTOFF WALL CONSISTING OF
GROUT, CONCRETE, BENTONITE
OR OTHER MATERIAL
APPROVED BY A MINIMUM 1-FOOT
ABOVE GRADE GEOTECHNICAL CONSULTANT
. . . . . .. ·. : ; . . ·. : : .. ~ ···.; .. : ···.; .
VER 1.0
20 FOOT MINIMUM
1-E--------------
SOLID PIPE PERFORATED PIPE
NOTE: LOCATION OF CANYON SUB DRAINS AND OUTLETS
SHOULD BE DOCUMENTED BY PROJECT CIVIL ENGINEER.
OUTLETS MUST BE KEPT UNOBSTRUCTED AT ALL TIMES.
CANYON SUBDRAIN TERMINUS
CANYON SUBDRAIN
ADVANCED GEOTECH ICAL SOLUTIONS
CUTOFF WALL
DIMENSIONS
DETAIL 1
NTS
12-INCH MINIMUM
ABOVE PIPE
......
........ APPROVED
FILTER
MATERIAL
6-INCHES MINIMUM,
ADJACENT TO AND
BELOW PIPE
OPTION 1
FILTER MATERIAL: _MINIMUM VOLUME OF
9 CUBIC FEET PER LINEAL
FOOT OF CAL TRANS
CLASS 2 PERMEABLE MATERIAL
12-INCH MINIMUM
ABOVE PIPE
APPROVED . ·. ·. · ·. : _-
FILTER --,1-i · · · · · ·
FABRIC, WITH
6-INCH
OVERLAP
APPROVED
DRAIN
MATERIAL
6-INCHES MINIMUM,
ADJACENT TO AND
BELOW PIPE
OPTION 2
DRAIN MATERIAL: MINIMUM VOLUME OF 9 CUBIC FEET
PER LINEAL FOOT OF 3/4-INCH MAX
ROCK OR APPROVED EQUIVALENT
SUBSTITUTE
FILTER FABRIC: MIRAFI 140 FILTER FABRIC OR
APPROVED EQUIVALENT SUBSTITUTE
PIPE: 6 OR 8-INCH ABS OR PVC PIPE OR APPROVED SUBSTITUTE WITH A MINIMUM
OF 8 PERFORATIONS (1/4-INCH DIAMETER) PER LINEAL FOOT IN
BOTTOM HALF OF PIPE
(ASTM D2751, SDR-35 OR ASTM D3034, SDR-35
ASTM D1527, SCHD. 40 OR ASTM D1785, SCHD. 40)
NOTE: CONTINUOUS RUN IN EXCESS OF 500 FEET REQUIRES 8-INCH DIAMETER PIPE
(ASTM D3034, SDR-35, OR ASTM D1785, SCHD. 40)
CANYON SUBDRAIN
DRAIN 2-FT. MIN DRAIN
MATERIAL
WITH
2-FT. MIN.
IE >I
~tf~:';~BRIC "> <"I2-FT.
: · ··.·.·· · MIN ------·~o· ._. _._ · .. ·-:·-_· .·_:-:_-. -7 ---'"'· ..
4-INCH SOLID 2-INCH MIN
OUTLET PIPE BELOW PIPE
FILTER FABRIC
OPTION 1
DRAIN MATERIAL: GRAVEL TRENCH TO BE FILLED WITH 3/4-INCH MAX ROCK OR APPROVED EQUIVALENT
SUBSTITUTE
FILTER FABRIC: MIRAFI 140 FILTER FABRIC OR EQUIVALENT SUBSTITUTE WITH A MINIMUM 6-INCH OVERLAP
VER 1.0
PIPE: 4-INCH ABS OR PVC PIPE OR APPROVED EQUIVALENT SUBSTITUTE WITH A MINIMUM
OF 8 PERFORATIONS (1/4-INCH DIAMETER) PER LINEAL FOOT IN
BOTTOM HALF OF PIPE
(ASTM D2751, SDR-35 OR ASTM D3034, SDR-35
ASTM D1527, SCHD. 40 OR ASTM D1785, SCHD. 40)
BUTTRESS/STABILIZATION DRAIN
DRAIN SPECIFICATIONS DETAIL 2
ADVANCED GCOTECH ICAL SOLUl IONS
NTS
2%M/N.
~WIDTH ~
CODE COMPLIANT KEYWAY
WITH MINIMUM DIMENSIONS:
TOE 2 FOOT MIN.
HEEL 3 FOOT MIN.
WIDTH 15 FOOT MIN.
BLANKET FILL -AS REQUIRED BY
GEOTECHNICAL CONSULTA NT
AND/OR CODE COMPLIANCE
(3 FOOT MIN.)
CODE COMPLIANT
SETBACK, 15 FOOT MIN.~
BENCH WIDTH
VARIES
I<
4 FOOT MIN.
BENCH HEIGHT
>I
SEE DETAIL 2 FOR DRAIN SPECIFICATIONS
NOTES:
1. DRAIN OUTLETS TO BE PROVIDED EVERY 100 FEET
CONNECT TO PERFORATED DRAIN PIPE BY "L" OR "T"
AT A MINIMUM 2% GRADIENT.
2. THE NECESSITY AND LOCATION OF ADDITIONAL
DRAINS SHALL BE DETERMINED IN THE FIELD
BY THE GEOTECHNICAL CONSULTANT. UPPER STAGE
OUTLETS SHOULD BE EMPTIED ONTO CONCRETE
TERRACE DRAINS.
3. DRAIN PIPE TO EXTEND FULL LENGTH OF
STABILIZATION/BUTTRESS WITH A MINIMUM GRADIENT
OF 2% TO SOLID OUTLET PIPES.
4. LOCATION OF DRAINS AND OUTLETS
SHOULD BE DOCUMENTED BY PROJECT
CIVIL ENGINEER. OUTLETS MUST BE KEPT
UNOBSTRUCTED AT ALL TIMES.
VER 1.0 NTS
STABILIZATION/BUTTRESS FILL DETAIL 3
ADVANCED GEOTECHNICAL SOLUTIONS
* THE "CUT" PORTION OF THE SLOPE SHALL
BE EXCAVATED AND EVALUATED BY THE
GEOTECHNICAL CONSULTANT PRIOR TO
CONSTRUCTING THE "FILL" PORTION
-
ENGINEERED FILL
I<
4 FOOT MIN.
BENCH HEIGHT
>I
___.,. -SUITABLE BEARING MATERIAL
SUITABLE
BEARING MATERIAL
VER 1.0
NOTES:
CODE COMPLIANT KEYWAY
WITH MINIMUM DIMENSIONS:
TOE: 2 FOOT MIN.
HEEL: 3 FOOT MIN.
WIDTH: 15 FOOT MIN.
1. THE NECESSITY AND LOCATION OF DRAINS
SHALL BE DETERMINED IN THE FIELD
BY THE GEOTECHNICAL CONSULTANT
2. SEE DETAIL 2 FOR DRAIN SPECIFICATIONS
FILL OVER CUT SLOPE
ADVANCED GEOTECHNICAL SOLUTIO S
DETAIL 4
NTS
A 1:1 MINIMUM
PROJECTION FROM DESIGN
SLOPE TOE TO TOE OF KEYWAY
RE-GRADE NATURAL SLOPE
WITH ENGINEERED FILL
/' ... . ' ..
VARIABLE '.-/ . ·--BACKCUT
...
_,,~<,.,1~ TOE ~~,"<., A,,/v~,,:: (,,<_~ _ ~:<.~,~<~Y'l,~{~~ ~ ,,,.,.~,..z~~~-<:<'l~{,(t,,.., 'f/':;:t.:{<'l,g,
ENGINEERED FILL
---·
IE >I
4 FOOT MIN.
BENCH HEIGHT
~-::2~%=M=/~N2.~i HEEL
SUITABLE BEARING MATERIAL
VER 1.0
~W IDTH ~
CODE COMPLIANT KEYWAY
WITH MINIMUM DIMENSIONS:
TOE: 2 FOOT MIN.
HEEL: 3 FOOT MIN.
WI DTH: 15 FOOT MIN.
NOTES:
1. WHEN THE NATURAL SLOPE APPROACHES OR
EXCEEDS THE DESIGN GRADE SLOPE RATIO,
SPECIAL RECOMMENDATIONS ARE NECESSARY
BY THE GEOTECHNICAL CONSULTANT
2. THE GEOTECHNICAL CONSULTANT WILL
DETERMINE THE REQUIREMENT FOR AND
LOCATION OF SUBSURFACE DRAINAGE SYSTEMS.
3. MAINTAIN MINIMUM 15 FOOT HORIZONTAL WIDTH
FROM FACE OF SLOPE TO BENCH/BACKCUT
-
NTS
~·~ACS FILL OVER NATURAL SLOPE DETAIL 5
AD\IANCED GEOTECHNICAL SOLUTIONS
VER 1.0
BENCH WIDTH Q VARIES
......----~ I<
4 FOOT MIN.
BENCH HEIGHT
>I
EXISTING GRADE ---,...
. . . ----
SUITABL E BEARING MATERIAL
HEEL
~ WIDTH ~
CODE COMPLIANT KEYWAY
WITH MINIMUM DIMENSIONS:
TOE: 2 FOOT MIN.
HEEL: 3 FOOT MIN.
WIDTH: 15 FOOT MIN.
NOTES:
1. MAINTAIN MINIMUM 15 FOOT HORIZONTAL WIDTH
FROM FACE OF SLOPE TO BENCH/BACKCUT
2. SEE DETAIL 2 FOR DRAIN SPECIFICATIONS
SKIN FILL CONDITION DETAIL 6
NTS
ADVA CED GEOTECH ICAL SOLUTIONS
----
VER 1.0
H1
....-
/
~O~/ /
~,~G;!:, / ~O~
~'f.-\S / ~ G
/ ~s\G 0 ..
UNSUITABLE
BEARING MATERIAL
(REMOVE)
--....---
/ 15 FOOT MIN.
/
-
,
, ·, ,
--;,. -BENCH WIDTH
VARIES
I< 4 FOOT MIN.
BENCH HEIGHT
>I
1 FOOT TILT BACK (MIN.)
-
, -
i SUITABLE BEARING MATERIAL
NOTES:
1. IF RECOMMENDED BY THE GEOTECHNICAL CONSULTANT,
THE REMAINING CUT PORTION OF THE SLOPE MAY REQUIRE
REMOVAL AND REPLACEMENT WITH AN ENGINEERED FILL
2. "W" SHALL BE EQUIPMENT WIDTH (15 FEET) FOR SLOPE HEIGHT
LESS THAN 25 FEET. FOR SLOPES GREATER THAN 25 FEET, "W" SHALL
BE DETERMINED BY THE GEOTECHNICAL CONSULTANT. AT NO
TIME SHALL "W" BE LESS THAN H/2
3. DRAINS WILL BE REQUIRED (SEE DETAIL 2)
DETAIL 7
ADVANCED GEOTECHNICAL SOLUTIO S
PARTIAL CUT SLOPE
STABILIZATION
NTS
--
DESIGN GRADE
--
,
5 FEET
MIN.
, ,
.t\.. ,' "., , , , ,
, ,
--EXISTING GR~E _ ---
** SUBSURFACE
DRAINAGE
' '
--
5 FEET
MIN.
', 7. ',·7
' ' ' ' ' '
SUITABLE BEARING MATERIAL REMOVE AND REPLACE
WITH ENGINEERED FILL
CUT LOT OVEREXCAVATION
DESIGN GRADE
, SUITABLE BEARING MATERIAL
CUT-FILL LOT OVEREXCAVATION
NOTES:
, ,
5 FEET
MIN.
---
DEPTH*
DEPTH*
..i,
* SEE REPORT FOR RECOMMENDED DEPTHS, DEEPER OVEREXCAVATION MAY BE REQUIRED BY
THE GEOTECHNICAL CONSULTANT BASED ON EXPOSED FIELD CONDITIONS
** CONSTRUCT EXCAVATION TO PROVIDE FOR POSITIVE DRAINAGE TOWARDS STREETS,
DEEPER FILL AREAS OR APPROVED DRAINAGE DEVICES BASED ON FIELD CONDITIONS
VER 1.0
ADVANCED GEOTECI-INICAL SOLUTIONS
CUT & CUT-FILL LOT
OVER EXCAVATION DETAIL 8
NTS
ENGINEERED FILL
(EXISTING)
DESIGN GRADE
ADDITIONAL
ENGINEERED FILL
(TO DESIGN GRADE)
SUITABLE BEARING MATERIAL
* REMOVE BEFORE PLACING ADDITIONAL ENGINEERED FILL
VER 1.0
~ -~AGS
TYPICAL UP-CANYON PROFILE
REMOVAL ADJACENT TO
EXISTING FILL
ADVANCED GEOTECHNICAL SOLUTIONS
NTS
DETAIL 9
VER 1.0
DESIGN GRADE
CLEAR ZONE 10 FEET
4 FEET
0 t O< 15 FEET >JI};
ENGINEERED FILL TYPICAL WINDROWS,
PLACED PARALLEL TO
SLOPE FACE
.... .... .... .... .... .... .... .........
CLEAR ZONE DIMENSIONS FOR REFERENCE ONLY, ACTUAL DEPTH, WIDTH,
WINDROW LENGTH, ETC. TO BE BASED ON ELEVATIONS OF FOUNDATIONS,
UTILITIES OR OTHER STRUCTURES PER THE GEOTECHNICAL CONSULTANT OR
GOVERNING AGENCY APPROVAL
OVERSIZED MATERIAL DISPOSAL PROFILE
----------------
(f OT] ~~~~~TE~~ci~~L~ :~~~EN (]D}) \w) WINDROWS ,~w)
-------/-------
HORIZONTALLY PLACED ENGINEERED FILL, FREE OF OVERSIZED MATERIALS AND
COMPACTED TO MINIMUM PROJECT STANDARDS
COMPACT ENGINEERED FILL ABOVE OVERSIZED MATERIALS TO FACILITATE
"TRENCH" CONDITION PRIOR TO FLOODING GRANULAR MATERIALS
WINDROW CROSS-SECTION
----------------
ENGINEERED FILL u· .. •rJ{jQQ ii
--l -•> 7 -=--.J --
GRANULAR MATERIALAPPROVED BY
THE GEOTECHNICAL CONSULTANT AND
CONSOLIDATED IN-PLACE BY FLOODING
WINDROW PROFILE
..... __ _
NTS
8AGS OVERSIZED MATERIAL
DISPOSAL CRITERIA
DETAIL 10
ADVANCED GEOTECHNICAL SOLUTIONS
VER 1.0
DESIGN GRADE
3/4-INCH PIPE COU PLING
3/4-INCH PIPE NIPPLE WELDED
TO SETTLEMENT PLATE
FOUND PLATE ON ONE-FOOT
COMPACTED SAND BEDDING
c1
~ -~
~ -
PROTECT IN-PLACE AT DESIGN GRADE
-
3-INCH SCH EDULE 40 PVC PIPE
CTIONS ATTACHED 5-FOOT SE
WITH GLUE D COUPLING JOINTS
EXTENSION
5-FOOT SEC
ROD CONSISTING OF
TIONS OF 3/4-INCH
GALVANIZE D PIPE, TOP AND
READED BOTTOM TH
SETTLEMENT PLATE,
2' x 2' x 1/4" STEEL
T 7 Y0")0',~'w. '%i~ >1.',.'/fT -,,_~~,Y..',<Nii :?,~N)'t~,<_v
2 FEET I.·.-;:._ .. _._:_.·;· .. ·.·:-::_:_:·.-:·:.-:-::_:·_: --_:::_I SUITABLE BEARING MATERIAL L ~-:-~~:-.-:--._-~ :---:-.-:-:-::-~--J> :--:·-~-.-:-:--.:-:::--:.-:--.:-~:--:-~<--~-:--.~~~i
NOTES:
1. SETTLEMENT PLATE LOCATIONS SHALL BE SUFFICIENTLY IDENTIFIED BY THE
CONTRACTOR AND BE READILY VISIBLE TO EQUIPMENT OPERATORS.
2. CONTRACTOR SHALL MAINTAIN ADEQUATE HORIZONTAL CLEARANCE FOR EQUIPMENT
OPERATION AND SHALL BE RESPONSIBLE FOR REPAIRING ANY DAMAGE TO
SETTLEMENT PLATE DURING SITE CONSTRUCTION.
3. A MINIMUM 5-FOOT ZONE ADJACENT TO SETTLEMENT PLATE/EXTENSION RODS SHALL BE
ESTABLISHED FOR HAND-HELD MECHANICAL COMPACTION OF ENGINEERED FILL.
ENGINEERED FILL SHALL BE COMPACTED TO MINIMUM PROJECT STANDARD.
4. ELEVATIONS OF SETTLEMENT PLATE AND ALL EXTENSION ROD PLACEMENT SHALL BE
DOCUMENTED BY PROJECT CIVIL ENGINEER OR SURVEYOR.
NTS
SETTLEMENT PLATE DETAIL 11
ADVANCED GEOTECHNICAL SOLUTIONS
VER 1.0
SPRINKLER VAULT,
PLACED ABOVE GRADE
DESIGN GRADE PVC CAP
/ TO REDUCE SEDIMENT INFILL
NOTES:
3 FEET
MINIMUM
I •
Ii
i
~ PVCPIPE
REBAR OR
MIN. 6-INCH FLAT HEADED BOLT
WITH 2-INCH CLEARANCE AND
SURROUNDED WITH PVC PIPE
--+--CONCRETE OR
-SLURRY BACKFILL
ENGINEERED FILL
1. SETTLEMENT MONUMENT LOCATIONS SHALL BE SUFFICIENTLY IDENTIFIED
AND BE READILY VISIBLE TO EQUIPMENT OPERATORS.
2. ELEVATIONS OF SURFACE MONUMENTS SHALL BE DOCUMENTED BY
PROJECT CIVIL ENGINEER OR SURVEYOR.
NTS
SETTLEMENT MONUMENT DETAIL 12
ADVANCED GEOTECHNICAL SOLUTIONS
APPENDIXC
HOMEOWNER MAINTENANCE RECOMMENDATIONS
ADVANCED GEOTECHNICAL SOLUTIONS, INC.
HOMEOWNER MAINTENANCE AND IMPROVEMENT CONSIDERATIONS
Homeowners are accustomed to maintaining their homes. They expect to paint their houses periodically,
replace wiring, clean out clogged plumbing, and repair roofs. M aintenance 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 than 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 s lope 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.
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.
Expansive Soils
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 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.
Homeowners purchasing 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. Provis ions 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 ma intenance provisions should include:
❖ Employing contractors 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.
❖ A voiding the construction of planters adjacent to structural improvements. Alternatively, planter
s ides/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 potential for moisture infiltration into the subgrade soils.
ADVANCED GEOTECHNICAL 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 a ll 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 in stalled to carry roof runoff directly into area drains or discharged well away
from the structures.
❖ Avoiding the placement of trees closer to the proposed structures than a distance of one-half the
mature he ight of the tree.
❖ Observation of the soil conditions around the perimeter of the structure during extremely hot/dry
or unusua lly wet weather conditions so that modifications can be made in irrigation programs to
maintain relatively constant moisture conditions.
Sulfates
Homeowners should be cautioned against the import and use of certain ferti lizers, 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 "negligible" 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 peri od 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 substances.
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 face, leaking irrigation systems, over-watering or other conditions which
could lead to ground saturation must be avoided.
❖ Before the rainy season arrives, check 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 GEOTECHNICAL SOLUTIONS, 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 dra in openings (weep-holes) clear of debris and other materi al which co uld
block them in a storm.
❖ Check for loose fill above and below your property if you live on a slope or terrace.
❖ Monitor hoses and sprinklers. During the rainy season, 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.
❖ Never block terrace drains and brow ditches on s lopes or at the tops of cut or fill slopes. These are
designed to carry away runoff to a place where it can be safely d istributed.
❖ Maintain the ground surface upslope 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.
❖ 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 till or natural ground), or will overflow into the
slope and begin erosion. Once erosion is started, it is difficult to control and severe damage may
result rather quickly.
❖ Never connect 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 o ut 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. Subdrains are constructed to take care of ordinary
subsurface water and cannot handle the overload from roofs during a heavy rain.
❖ 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 fi ll slopes, can eat away carefully
designed and constructed sites.
❖ 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.
❖ 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 ground and, if located close to slopes, may cause
slope failure in their vicinity.
❖ Do not discharge surface water into septic tanks or leaching fields. Not only are septic tanks
constructed for a different purpose, but they will tend, because 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.
❖ 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 we ight and
weakening of the near-surface soil. Planted slopes should be planned where possible to acquire
sufficient moisture when it rains.
❖ Do not let water gather against fo undations, retaining walls, and basement wall s. These walls are
built to withstand the ordinary moisture in the ground and are, where necessary, accompanied by
subdrains to carry off the excess. If water is permitted to pond against them, it may seep through
ADVANCED GEOTECHNICAL SOLUTIONS, 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 o r near a s lope, 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.
❖ Seeding and planting of the slopes sho uld 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.
❖ The resident is responsible for proper irrigation and for maintenance and repair of properly
installed irrigation 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 expertise in hill side maintenance.
Geotechnical Review
Due to the fact that soil types may vary with depth, it is recommended that plans for the construction of
rear yard improvements (swimming pools, spas, barbecue pits, patios, etc.), be reviewed by a geotechnical
engineer who is familiar with local conditions and the current standard of practice in the vicinity of your
home.
In conclusion, your neighbor's slope, above or below your property, is as important to you as the slope
that is within your property lines. For this reason, it is des irable 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 important to enhance slope and foundation stability and to prevent erosion of the near surface
soils. In addition, landscape improvements should provide for efficient drainage to a controlled discharge
location downhill of residentia l 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 GEOTECHNICAL SOLUTIONS, INC.
APPENDIXD
PRELIMINARY STORM WATER INFILTRATION FEASIBILITY ANALYSIS
ADVANCED GEOTECHNICAL SOLUTIONS, INC.
APPENDIX D
INFILTRATION TESTING
1.0 TESTING METHODS AND PROCEDURES
To evaluate feasi bility for infiltration onsite and to provide preliminary design infiltration rates, three (3)
borehole percolation tests were performed in general conformance with Appendix D, Section D.3.3.2 of
the recently adopted BMP Design Manual.
To provide representative continuous soil/geologic logs for the percolation test holes, two of the
percolation test borings were located adjacent to exploratory soil borings that were logged and sampled as
part of our investigation (TB-I and TB-2). A third boring (HS-3), utilizing the hoHowstem auger rig, was
drilled and logged to a depth of approximately 6 feet from existing design grade in the approximate
location of the single family units (Parcel B). Based upon the lithology observed in the other borings HS-
I thru HS-4, TB-I & TB-2 the lithology was found to be relatively uniform with a minor increase in
depth of the geologic contact with the Santiago formation along north to northwestern portion of the
Home Avenue portion of the project. Locati ons of the percolation test holes and the exploratory soil
borings are shown on Plate I, included herewith.
The percolation boreholes (P-1 and P-2) were excavated with a limited access tripod drill rig utilizing a 6-
inch diameter flight auger, and extended to depths of approximately "48" below ground surface.
Borehole HS-3 was excavated with a CME 75 truck-mounted hollowstem auger drill rig and extended
through topsoil o r undocumented artificial fill, into Old Paralic Deposits. The Old Paralic Deposits can
generally be described as a fine-grained, light brown to light gray sand that is slightly moist to moist and
medium dense to dense. A third percolation hole utilized the geotechnical boring HS-3 in the northwest
comer of Parcel B. This percolation test is identified as HSP-3 and extended to a total depth of 72 inches
form exiting grade.
The resulting test holes were cleaned of loose debris, then filled with several gall ons of clean, potable
water and allowed to pre-soak overnight. The following day the test holes were cleaned of sediment and
the bottom was lined with approximately 2-inches of washed gravel prior to percolation testing. A series
of falling head percolation tests were then performed. Test holes P-1 through P-3 were filled with clean,
potable water to a minimum of 20 inches above the bottom of the test hole and allowed to infiltrate. The
water levels was allowed to drop for a 30-minute period, the water level was then measured and the drop
rate calculated in inches per hour. Infiltration test borings P-1 and P-2 were dry after the 30 minute
period. Therefore, the sandy soil criteria was met and the time interval for those two test borings was
decreased to 10 minute intervals. The test holes were then refilled with water as necessary and the test
procedure was repeated over the course of approximately 6 hours for test borings HS-3 and until a
stabilized percolation rate was recorded for test borings P-1 and P-2.
The stabilized percolation rate was then converted to an infiltration rate based on the "Porchet Method"
utilizing the following equation:
Where:
I, = ~(&_ = AH 60 r
L'1t(nr·2rrrH.,~) L'1t(r+-2H.,g)
I, = tested infiltration rate, inches/hour
LlH -change in head over the time interval, inches
.1'1t = time interval, minutes
r -effective radius oftest hole
Havg = average head over the time interval, inches
Logs of the field testing and graphical representations of the test data presented as infiltration versus time
interval are attached herewith as supporting documents for Worksheet C.4-1.
2.0 TEST RESULTS AND PRELIMINARY DESIGN VALUES
The results of our testing are summarized in Table I below.
TABLE I
SUMMARY OF INFJLTRATION/PERCOLAT1ON TEST RESULTS
Approximate Tested Test Depth of Test
Hole No. Location Hole Test Elevation Geologic Unit Description Infiltration Rate
ft. above msl (inches/hour)
P-1 800 Grand 48" (4') 62 msl Qop Medium to Fine-
grained Sand
P-2 800 Grand 48" (4') 61 msl Qop Medium to Fine-
grained Sand
HSP-3 Home Ave 72" (6') 57 msl Qop Medium to Fine-
grained Sand
In accordance with Appendix D, Section D.5 of the BMP Design Manual, a 'Factor of Safety' should be
applied to the tested infiltration rates to determine the design infiltration rates. The factor of safety is
determined by Worksheet D.5-1 and possesses a numerical value between 2 and 9. For the proposed
project site, the factor of safety worksheet yielded a Combined Factor of Safety (S101a1) of 3. However, for
the purposes of feasibility screening, it is recommended by San Diego County that a Factor of Safety of
2.0 be utilized. Table 2 below summarizes the design infiltration rates for the subject test holes utilizing a
factor of safety of 2.0.
TABLE2
SUMMARY OF DESIGN INFILTRATION RA TES
Test Hole No. Location Tested Infiltration Factor of Safety Design Infiltration
Rate (in /hr.) Rate (in./hr.)
P-1 800 Grand 2.0 2.0 1.0
P-2 800 Grand 2.83 2.0 1.42
HSP-3 Home Ave 0.77 2.0 0.39
AVERAGE RATE 0.93
2.00
2.83
0.77
3.0 DESIGN CONSIDERATIONS
3.1. Groundwater
The soil borings extended ten feet or greater below the bottom of the percolation test borings and
encountered groundwater/saturated soil as summarized in table 3.
TABLE3
SUMMARY OF DEPTH TO GROUNDWATER
Test Hole No. Location I Depth To Groundwater
P-1 800 Grand 14*
P-2 800 Grand 15*
HSP-3 Home Ave 16.5 *
*-Extrapolated from adjacent boring
Based on our observations and experience with similar projects in the vicinity, the seasonal high
groundwater is anticipated to be approximately 14 feet below existing grade (approximate
elevation 48 msl).
3.2. Geotechnical Hazards
Slopes greater than 25% are not present onsite. Retaining walls and/or basement structures are
proposed on the partially subterranean 800 Grand portion of the site. Dependent on final design,
utility trenches (Parcel A & B) and basement walls (Parcel A) in proximity to BMP basins could
be subject to water intrusion. It is recommended that if infiltration is to be used it should only be
used on the Home A venue portion and should be located a minimum of 25 to 30 feet away from
the southerly edge of the Grand A venue structure.
3.3. Soil and Groundwater Contamination
During our recent site investigation, no soil contamination was observed, nor is any
contamination known to exist onsite. Groundwater was not encountered during out subsurface
investigations, and is not anticipated to be contaminated. Based on the State of California
Regional Water Quality Control Board (RWQCB) GeoTracker website, the closest site that had
environmental issues is located at 880 Carlsbad Village Drive, approximately 0.1 mile
southeasterl y of the subject site. That site is listed as a leaking underground storage tank (LUST)
site that has a clean-up status as "completed", and the RWQCB case for that site is now closed.
3.4. Pretreatment prior to infiltration
At this time, it is not anticipated that stormwater will undergo pretreatment such as sedimentation
or filtration prior to infiltration.
3.5. Soil Characteristics
3.6.
The infiltration surfaces are in Old Paralic Deposits. As encountered, these material can
generally be described as medium to fine-grained sand with some silt, in a medium dense to
dense condition. This unit exhibited favorable characteristics for infiltration and appeared to be
relatively uniform, but somewhat denser with depth.
Proximity to water supply wells
No water supply wells are known to exist within I 00 feet of the proposed basin.
4.0 CONCLUSIONS AND RECOMMEND A TIO NS
Based on the results of our preliminary infiltration testing, the onsite soils possess observed infiltration
rates rangi ng between 0.77 and 2.83 inches/hour. When utilizing a factor of safety of 2, preliminary
design infiltration rates range between 0.39 and 1.42 inches/hour, with an recommended average design
infiltration rate of 0.94 inches/hour. Based on the results of our site specific testing, infiltration rates for
the project site are above 0.50 inches/hour. For the Home Avenue, single family residential portion of the
site it is our opinion that partial or full infiltration is feasible. For the southern portion of the project (800
Grand) which will consist of the partially subterranean condominium structure it is our opinion that
infiltration is not feasible due to the potential for water intrusion and for additional hydrostatic pressure
on the proposed subterranean garage. Accordingly infiltration on the 800 Grand portion of the site project
should not be considered.
ATTACHMENTS
STORM WATER STANDARDS BMP DESIGN MANUAL-WORKSHEET FORM C.4-1
SUPPORT DOCUMENTS AND FIELD DA TA
Part 1 -Full Infiltration Feasibility Screening Criteria
Would infiltration of the full design volume be feasible from a physical perspective without any undesirable
consequences that cannot be reasonably mitigated?
Criteria Screening Question Yes No
Is the estimated reliable infiltration rate below proposed facility locations
greater than 0.5 inches per hour? The response to this Screening Question
shall be based on a comprehensive evaluation of the factors presented in
Appendix C.2 and Appendix D.
Provide basis:
□
Two (2) borehole percolation tests were performed in proposed/possible BMP locations. Testing was performed
in general conformance with Appendix D, Section D.3.3.2 of the recently adopted BMP Design Manual. The
stabilized percolation rates were then converted to infiltration rates using the "Porchet Method". The observed
infiltration rates were calculated to be: 2.0 inches/hour in test hole P-1 and 2.83 inches/hour in test hole P-2. Using
a factor of safety of 2 for feasibility screening purposes yielded design infiltration rates of 1.00 in/hr and 1.42
in/hr. Inclusive of the additional infiltration test on the Home Ave (0.38in/hr) yields an average infiltration rate of
0.93 in/hr.
2
Can infiltration greater than 0.5 inches per hour be allowed without increasing
risk of geotechnical hazards (slope stability, groundwater mounding, utilities,
or other fa ctors) that cannot be mitigated to an acceptable level? The response
to this Screening Question shall be based on a comprehensive evaluation of
the fa ctors presented in Appendix C.2.
Provide basis:
□
The average infiltration rates at this portion of the project site are greater than 0.5 inches/hour. However,
infiltration is not recommended due to the adverse affects the infiltration water may have on the subterranean
parking garage (increase in hydrostatic pressure, water proofing issues with the structure, and buoyancy issues
which could result in differential settlement).
Summarize findings of studies; provide reference to studies, calculations, maps, data sources, etc. Provide
narrative discussion of study/ data source applicability.
Criteria
3
Screening Question
Can infiltration greater than 0.5 inches per hour be allowed without increasing
risk of groundwater contamination (shallow water table, stonn water
pollutants or other factors) that cannot be mitigated to an acceptable level?
The response to this Screening Question shall be based on a comprehensive
evaluation of the factors presented in Appendix C.3.
Provide basis:
Yes No
□
No known contamination exists at the site and the closest know site with contamination issues is located
approximately 0.1 miles southeast of the site.
Summarize findings of studies; provide reference to studies, calculations, maps, data sources, etc. Provide
narrative discussion of study/ data source applicability.
4
Can infiltration greater than 0.5 inches per hour be allowed without causing
potential water balance issues such as change of seasonality of ephemeral
streams or increased discharge of contaminated groundwater to surface
waters? The response to this Screening Question shall be based on a
comprehensive evaluation of the factors presented in Append.ix C.3.
Provide basis:
□
The design infiltration rates at the project site are greater than 0.5 inches/hour. In filtration at a rate greater than
0.5 inches/hour is not feasible for this project due to the subterranean component of the structure. As such, this
screening question does not control the feasibility of infiltration at the project site. Per Section C.4.4 of the BMP
Design Manual, final determination should be made by the project design engineer.
Part 1
Result*
If all answers to rows 1-4 are "Yes" a full infiltration design is potentially feasible.
The feasibility screening category is Full Infiltration
If any answer from row 1-4 is "No", infiltration may be possible to some extent but
would not generally be feasible or desirable to achieve a "full infiltration" design.
Proceed to Part 2
*To be completed using gathered site information and best professional judgment considering the definition of MEP
in the MS4 Permit. Additional testing and/or studies may be required by the City Engineer to substantiate findings
Part 2-Partial Infiltration vs. No Infiltration Feasibility Screening Criteria
Would infiltration of water in any appreciable amount be physically feasible without any negative
consequences that cannot be reasonably mitigated?
Criteria
5
Screening Question
Do soil and geologic conditions allow for infiltration in any appreciable rate
or volume? The response to this Screening Question shall be based on a
comprehensive evaluation of the factors presented in Appendix C.2 and
Appendi." D .
Provide basis:
Yes No
□
As discussed in our response to C riteria No. I, site specific infiltration testing yielded infiltration rates of greater
than 0.5 inches/hour. The sandy nature of the subsurface materials beneath the site, allow for infiltration in an
appreciable rate or volume. It is anticipated that over the lifetime of the development the infiltration rates will
further diminish. The BMP Design Manual utilizes the subjective terminology of 'appreciable' and fails to define
a lower bound infi ltration rate. It is our current understanding that an 'appreciable' infiltration rate is interpreted
to be any perceptible amo unt of infiltration. Therefore, in consideration of the current interpretation, the soil and
geologic conditions at the project site allow for infiltration in an 'appreciable' rate or volume.
6
Can Infiltration in any appreciable guantity be allowed without increasing
risk of geotechnical hazards (slope stability, groundwater mounding, utilities,
or other factors) that cannot be mitigated to an acceptable level? The
response to this Screening Question shall be based on a comprehensive
evaluation of the factors presented in Appendix C.2.
Provide basis:
□
For the "Grand Avenue" Condominium structure supported by the proposed partially subterranean garage,
infiltration may create unwanted mounding and hydrostatic pressures on the buried portions of the structure.
Accordingly , it is our opinion that the condominium portion is not suitable for infiltration.
Criteria
7
Screening Question
Can Infiltration in any appreciable quantity be ailowed without posing
significant risk for groundwater related concerns (shallow water table, storm
water pollutants or other factors)? The response to this Screening Question
shail be based on a comprehensive evaluation of the factors presented in
Appendix C.3.
Provide basis:
Yes No
□
T he proposed basin location has adequate separation ( 10 feet) to seasonal hi gh groundwater. There are no known
water supply wells within 100 feet of the project site. According to the State Water Board's Geotracker website,
the closest site with contamination issues is located 0.1 miles from the si te. That site is reported as a LUST
cleanup, and the case has been closed. Land use in the project vicinity is predominantl y multi-family residential
with locall y interspersed commercial/retail. T here are no known contamination risks from current land use
activities. As such, we do not anticipate that construction of the proposed BMP basin will adversely impact
receiving channels in the project vici nity.
8
Can infiltration be allowed without violating downstream water rights? The
response to this Screening Q uestion shall be based on a comprehensive
evaluation of the factors presented in Appendix C.3.
Provide basis:
□
The project site is graded and is located in a developed neighborhood with impermeable surfaces where surface
waters are controlled and directed to storm drain inlets. There is no apparent evidence that construction of BMP
basins would divert or otherwise preclude fl ow to downstream water bodies. Per Section C.4.4 of the BMP
Design Manual, final determination should be made by the project design engineer.
Part 2
Result*
If all answers from row 5-8 are "Yes", then partial infiltration design is potentially
feasible. The feasibility screening category is Partial Infiltration.
If any answer from row 5-8 is "No", then infiltration of any volume is considered to be
infeasible within the drainage area. The feasibility screening category is No Infiltration.
*To be completed using gathered site information and best professional judgment considering the definition of
MEP in the MS4 Permit. Additional testing and/or studies may be required by the City Engineer to substantiate
findings
Part 1 -Full Infiltration Feasibility Screeoin2 Criteria
Would infiltration of the full design volume be feasible from a physical perspective without any undesirable
consequences that cannot be reasonably mitigated?
Criteria Screening Question
Is the estimated reliable infiltration rate below proposed facility locations
greater than 0.5 inches per hour? The response to this Screening Question
shall be based on a comprehensive evaluation of the factors presented in
Appendix C.2 and Appendix D.
Provide basis:
Yes No
□
One (I ) borehole percolation tests was performed in proposed/possible BMP location. One was conducted for
Home Ave single family detached (HS-3); and two were conducted for the 800 Grand condominium portion Pl
and P2 . Testing was performed in general conformance with Appendix D, Section D.3.3.2 of the recently adopted
BMP Design Manual. The stabilized percolation rates were then converted to infiltration rates using the "Porchet
Method". The observed infi ltration rates were calculated to be 0.77 inches/hour in test hole HSP-3 (Home Ave)
and 2.0 inches/hour in test hole P-1 and 2.83 inches/hour in test hole P-2 on the Grand Ave. portion. Using a factor
of safety of 2 for feasibility screening purposes yielded design infiltration rates of 0.39(Home Ave). Using a
factor of safety of 2 for feasibility screening purposes yielded design infiltration rates of 1.00 in/hr and 1.42 in/hr.
and 0.38in/hr. It is our opinion that an average infiltration rate of 0.93 in/hr should be used for both sites given the
similar soils and geology.
2
Can infiltration greater than 0.5 inches per hour be allowed without increasing
risk of geotechnical hazards (slope stability, groundwater mounding, utilities,
or other factors) that cannot be mitigated to an acceptable level? The response
to this Screening Question shall be based on a comprehensive evaluation of
the factors presented in Appendix C.2.
Provide basis:
□
Yes an infiltratjon rate of 0.93in/hr can be used for the design of possible infiltration on the Home Avenue
portion of the project. T his opinion is based upon: the similarity of the soils exposed in the 3 percolation
test borings; the lower rate found in HS-1 is likely related to the near surface compaction as a result of the
original parking lot and drive isle construction activities. The types of soils and the blow counts within the
upper soils are relatively uniform. Accordingly, once the proposed infiltration section is cut to the design
grade (18 to 24 inches) it is conservatively estimated that the average rate presented herein can be utilized for
design.
Based upon the proposed location in the drive aisles/parking areas it is not anticipated that this will
adversely affect the proposed improvements provided the building slabs are adeguately waterproofed with a
suitable moisture barrier and the buried utility lines are located outside of the pervious pavement or
adeguately backfilled with a sand cement slurry where they intercept the permeable pavement.
Summarize findings of studies; provide reference to studies, calculations, maps, data sources, etc. Provide
narrative discussion of study/ data source applicability.
Criteria
3
Screening Question
Can infiltration greater than 0.5 inches per hour be allowed without increasing
risk of groundwater contamination (shallow water table, sronn water
pollutants or other factors) that cannot be mitigated to an acceptable level?
The response to this Screening Question shall be based on a comprehensive
evaluation of the factors presented in Appendix C.3.
Provide basis:
Yes No
□
No known contamination exists at the site and the closest know site with contamination issues is located
approximately 0.1 miles southeast of the site.
Summarize findings of studies; provide reference to studies, calculations, maps, data sources, etc. Provide
narrative discussion of study/ data source applicability.
4
Can infiltration greater than 0.5 inches per hour be allowed without causing
potential water balance issues such as change of seasonality of ephemeral
streams or increased discharge of contaminated groundwater to surface
waters? The response to this Screening Question shall be based on a
comprehensive evaluation of the factors presented in Appendix C.3.
Provide basis:
□
The design infiltration rates at the Home Ave portion of the project are suitable provided they do not infiltrate
into the buried utilities and that they are a minimum of 25 to 30 feet horizontally away from the Grand Ave
podium structure and drain in a south to north direction. Per Section C.4.4 of the BMP Design Manual, final
determjnation should be made by the project design engineer.
Part 1
Result*
If all answers to rows 1-4 are "Yes" a full infiltration design is potentially feasible.
The feasibility screening category is Full Infiltration
If any answer from row 1-4 is "No", infiltration may be possible to some extent but
would not generally be feasible or desirable to achieve a "full infiltration" design.
Proceed to Part 2
*To be completed using gathered site information and best professional judgment considering the definition of MEP
in the MS4 Permit. Additional testing and/or studies may be required by the City Engineer to substantiate findings
Part 2 -Partial Infiltration vs, No Infiltration Feasibility Screening Criteria
Would infiltration of water in any appreciable amount be physically feasible without any negative
consequences that cannot be reasonably mitigated?
Criteria
5
Screening Question
D o soil and geologic conditions allow for infiltration in any appreciable rate
or volume? The response to this Screening Question shall be based on a
comprehensive evaluatio n of the factors presented in Appendix C.2 and
Appendix D.
Provide basis:
Yes No
□
Site specific infiltration testing yielded infiltration rates of greater than 0.5 inches/hour. The sandy nature of the
subsurface materials beneath the site, allow for infiltration in an appreciable rate or vol ume. It is anticipated that
over the lifetime of the development the infiltration rates will further diminish. The BMP Design Manual utilizes
the subjective terminology of 'appreciable' and fails to defi ne a lower bound infiltration rate. It is our current
understanding that an 'appreciable' infiltration rate is interpreted to be any perceptible amount of infiltration.
Therefore, in consideration of the current interpretation, the soil and geologic conditions at the project site allow
for infiltration in an 'appreciable' rate or volume.
6
Can Infiltration in any appreciable quantity be allowed without increasing
risk of geotechnical hazards (slope stability, groundwater mounding, utilities,
or other factors) that cannot be mitigated to an acceptable level? The
response to this Screening Q uestion shall be based on a comprehensive
evaluation of the factors presented in Appendix C.2.
Provide basis:
□
Partial Infiltration can be allowed in the proposed BMP basin/Permeable pavement locations without
significantly increasing the risk of geotechnical hazards provided appropriate mitigation/remedial grading
measures are performed during site development/basin construction. The infiltration surface for the proposed
BMPs have not been finalized at this time, however, it is expected that they will be within the native material at
the site (Old Paralic Deposits) As encountered, the Old Paralic Deposits beneath the site, consist predominantly
of sand and silty sand, in a dense to very dense condition. Some gravely sand was observed at the bottom of the
Old Paralic Deposits. Below the Old Paralic Deposits, a less permeable silty claystone was encountered and
assigned to the Santiago Formation. More detailed recommendations should be provided when final design
plans become available. For the "Home" Avenue portion of the development it is our opinion that infiltration
within the proposed dri veways and parking lots is suitable.
Criteria Screening Question Yes No
7
Can Infiltration in any appreciable guantity be allowed without posing
significant risk for groundwater related concerns (shallow water table, storm
water pollutants or other factors)? The response to this Screening Question
shall be based on a comprehensive evaluation of the factors presented in
Appendi"X C.3.
Provide basis:
D
The proposed basin location has adequate separation (>IO feet) to seasonal hi gh groundwater. There are no
known water supply wells withi n 100 feet of the project site. According to the State Water Board's Geotracker
website, the closest site with contamination issues is located 0.1 miles from the site. That site is reported as a
LUST cleanup, and the case has been closed. Land use in the project vicinity is predominantly multi-family
residential with locally interspersed commercial/retail. There are no known contamination risks from current land
use activities. As such, we do not anticipate that construction of the proposed BMP basin will adversely impact
receiving channels in the project vicinity.
8
Can infiltration be allowed without violating downstream water rights? The
response to this Screening Question shall be based on a comprehensive
evaluation of the factors presented in Appendix C.3.
Provide basis:
D
The project site is graded and is located in a developed neighborhood with impermeable surfaces where surface
waters are controlled and directed to storm drain inlets. There is no apparent evidence that construction of BMP
basins would divert or otherwise preclude flow to downstream water bodies. Per Section C.4.4 of the BMP
Design Manual, fi nal determination should be made by the project design engineer.
Part 2
Result*
If all answers from row 5-8 are "Yes", then partial infiltration design is potentially
feasible. The feasibility screening category is Partial Infiltration.
If any answer from row 5-8 is "No", then infiltration of any volume is considered to be
infeasible within the drainage area. The feasibility screening category is No Infiltration.
*To be completed using gathered site information and best professional j udgment considering the definition of
MEP in the MS4 Permit. Additional testing and/or studies may be required by the City Engineer to substantiate
findings
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/
GEOLOGIC MAP PLATE 1
~~~ ~t\G s AD\IANCED GEOTECHNICAL SOLUTIONS, INC.
-485 Corporale Drive, Suite B
Escondido. California 92029
:,,,.,, Telephone: (714) 786-5661 Faxc (71 4)409-3287
Project# Report# Date:
P/W 1607-03 1607--03-8-2 October 2016
b~A,lnc.
land plan;nlng, cMI englneeling, surveying
5115 AVEN ID A ENCINAS
SUITE "L"
CARLSBAD, CA. 92008-4387
(760) 931-8700
SHEET20F3
A
700
680
....---... I-LL. ...__,.
z:
0 660 I-
<C > w
_J HS-3 w
640 --i--?--
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---------
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afu
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LEGEND:
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............._ __ Assumed ( +6") Finish Grade
CROSS SECTIONS A-A', AND 8-8'
SCALE H&V 1 "=20'
PLATE2 \1\G s ADVANCED GEOTECHNIC/U. SOLUTIONS, INC
485 Corporate Drive, Suite B
Escondido, California 92029 ~ Telephone: (714) 786-5661 Fax: (714) 409-3287
Report# Date:
1607-03 October 2016