HomeMy WebLinkAboutDEV 2016-0070; DEMPSEY RESIDENCE; GEOTECHNICAL INVESTIGATION PROPOSED DEMPSEY RESIDENCE; 2016-12-30I
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CljE Inc.Construction Testing & Engineering, Inc.
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GEOTECHNICAL INVESTIGATION
PROPOSED DEMPSEY RESIDENCE
APN: 215-491-36-00, BOLERO STREET
CARLSBAD, CALIFORNIA
RECORD COPY
Initial Oate
Prepared for:
ATTENTION: MR. JOHN DEMPSEY
1835 ASTON AVENUE
CARLSBAD, CALIFORNIA 92008
Prepared by:
CONSTRUCTION TESTING & ENGINEERING, INC.
1441 MONTIEL ROAD, SUITE 115
ESCONDIDO, CALIFORNIA 92026
RECEIVED
JUL 1 4 20iv
LAND DEVELOPMENT
ENGINEERING
CTEJOBNO.; 10-13435G December 30, 2016
1441 Montiel Road. Suite 115 | Escondido. OA 92026 | Ph (760) 746^955 | Fax (760) 746-9806 | www.cte-inc.riet
TABLE OF CONTENTS
1.0 INTRODUCnON AND SCOPE OF SERVICES 1
1.1 Introduction 1
1.2 Scope of Services 1
2.0 SITE DESCRIPTION 2
3.0 FIELD INVESTIGATION AND LABORATORY TESTING 2
3.1 Field Investigation 2
3.2 Laboratory Testing 3
3.3 Percolation Testing 3
4.0 GEOLOGY 5
4.1 General Setting 5
4.2 Geologic Conditions 5
4.2.1 Quaternary Previously Placed FiU (Qppf) 5
4.2.2 Residual Soil (unmapped) 6
4.2.3 Metasedimentary and Metavolcanic Rocks Undivided (Mzu) 6
4.3 Groundwater Conditions 6
4.4 Geologic Hazards 6
4.4.1 Surface Fault Rupture 7
4.4.2 Local and Regional Faulting 7
4.4.3 Liquefaction and Seismic Settlement Evaluation 7
4.4.4 Tsunamis and Seiche Evaluation 8
4.4.5 Landsliding 8
4.4.6 Compressible and Expansive Soils 8
4.4.7 Corrosive Sods 9
5.0 CONCLUSIONS AND RECOMMENDATIONS 10
5.1 General 10
5.2 Site Preparation 10
5.3 Site Excavation 12
5.4 Fill Placement and Compaction 12
5.5 FUl Materials 13
5.6 Temporary Construction Slopes 14
5.7 Construction Shoring 15
5.8 Foimdation and Slab Recommendations 17
5.8.1 Foundations 17
5.8.2 Foundation Settlement 18
5.8.3 Foundation Setback 18
5.8.4 Interior Concrete Slabs 19
5.9 Seismic Design Criteria 20
5.10 Lateral Resistance and Earth Pressures 21
5.11 Exterior Flatwork 23
5.12 Drainage 24
5.13 Slopes 24
5.14 Plan Review 25
5.15 Construction Observation 25
6.0 LIMITATIONS OF INVESTTGATTON 26
FIGURES
FIGURE 1
nGURE2
FIGURES
nGURE4
SITE INDEX MAP
GEOLOGIC/EXPLORATION LOCATION MAP
REGIONAL FAULT AND SEISMICITY MAP
RETAINING WALL DRAINAGE DETAIL
APPENDICES
APPENDIX A
APPENDIX B
APPENDIX C
APPENDIX D
APPENDIX E
REFERENCES
EXPLORATION LOGS
LABORATORY METHODS AND RESULTS
STANDARD SPECIFICATIONS FOR GRADING
WORKSHEETS D.5-1 and 1-8
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1.0 INTRODUCnON AND SCOPE OF SERVICES
1.1 Introduction
This report presents results ofthe geotechnical investigation, performed by Construction Testing and
Engineering, Inc. (CTE), and provides preliminary conclusions and recommendations for the
proposed improvements at APN: 215-491-36-00 in Carlsbad, California. This work has been
performed in general accordance with the terms of Proposal No. G-3934.
CTE imderstands that site grades are to be raised with approximately 1,000 cubic yards of
compacted fidl soils and that proposed improvements are to include a one- to two-story residence
with flatwork, retaining walls, utilities, and other associated minor improvements. Preliminary
geotechnical recommendations for overexcavations, fill placement, and foimdation design for the
proposed improvements are presented in this report Selected references pertinent to this project are
provided in Appendix A.
1.2 Scope of Services
The scope of services provided included:
• Review of applicable geologic and geotechnical maps and reports.
• Excavation of exploratory borings and soil sampling utilizing a truck-mounted drill rig.
• Laboratory testing of selected soil samples.
• Percolation testing in general accordance with the Coimty of San Diego procedures.
• Description of site geology and evaluation of potential geologic hazards.
• Engineering and geologic analysis.
• Preparation of this prelinunary geotechnical investigation report
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2.0 SITE DESCRIPTION
The subject site, ■vvliich is identified as APN: 215-491-36-00, is located west of Bolero Street in
Carlsbad, California (Figure 1). The site is bounded by Bolero Street to the east, existing residences
to the north and south, and a descending slope to the west. Existing site conditions are illustrated on
Figures 1 and 2. The proposed improvement area currently consists of an undeveloped lot. Based
on reconnaissance and review of site topogr^hy, the site descends to the southwest with elevations
ranging from approximately 393 feet above mean sea level (msl) in the northeast to approximately
365 feet above msl in the southwest
3.0 FIELD INVESTIGATION AND LABORATORY TESTING
3.1 Field Investigation
CTE performed the field investigation on November 22 and 23,2016. The field work consisted of
site reconnaissance and excavation of three borings and three percolation test holes. The borings
were advanced to a maximum depth of approximately 11 feet below groimd surface (bgs) before
reaching practical refusal to further excavation in very dense metavolcanic rock. Bulk samples were
collected from the cuttings, and relatively undisturbed samples were collected by driving Standard
Penetration Test (SPT) and Modified California (CAE) samplers. The Borings were advanced with
a CME-75 truck-mounted drill rig equipped with eight-inch-diameter, hollow-stem augers.
Additionally, three test holes were excavated to depths ranging from ^proximately 2.5 to 5.0 feet
bgs for the purpose of percolation testing. The approximate location of the exploratory soil borings
and percolation test holes are shown on attached Figure 2.
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The sods were logged in the field by a CTE Engineering Geologist and were visually classified in
general accordance with the Unified Soil Classification System. The field descriptions have been
modified, where appropriate, to reflect laboratory test results. Boring logs, including descriptions of
the soUs encountered, are included in Appendix B. The approximate locations of the borings are
presented on Figure 2.
3.2 Laboratorv Testing
Laboratory tests were conducted on selected soil samples for classification purposes, and to evaluate
physical properties and engineering characteristics. Laboratory tests included: Expansion Index
(El), Gradation, and Chemical Characteristics. Test descriptions and laboratory test results are
included in Appendix C.
3.3 Percolation Testing
Three percolation tests were performed for potential storm water infiltration design and/or
evaluation. These tests were performed in general accordance with the County of San Diego
Department of Environmental Health (SD DEH) procedures. The tests were specifically performed
in accordance with SD DEH Case 1 and Case HI methods. The Case 1 Method is performed when
presoak water remains in the test hole overnight and Case in method is performed when presoak
water infiltrates through the test hole overnight The approximate percolation test locations are
presented on Figure 2. The percolation test results are presented ha the table below. The infiltration
rates have been calculated utilizdng a factor of safety of 3.5 based on the completed worksheet D.5-1
(Appendix E). If necessary, the project storm water or basin designer may modiJfy the factor of
safety based on an independent evaluation of Worksheet D.5-1 attached in Appendix E. The
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infiltration feasibility information is also presented on the completed 1-8 Worksheet attached in
Appendix E.
Test
Location
Soil Type San Diego
County
Percolation
Procedure
Depth
(ft)
Percolation Rate
(minutes/inch)
Infiltration
Rate (inches
per hour)
P-1 Residual SoU Case 1 5.0 Did Not Perc -
P-2 Residual Soil Case in 3.7 240 0.014
P-3 Residual Soil/Mzu Case 1 2.5 Did Not Perc -
Mzu = Metasedimentary and Metavolcanic Rock
The percolation test results were obtained in general accordance with City and County standards
(County of San Diego Department of Environmental Health Land and Water Quality Division) and
performed with the standard of care practiced by other professionals in the area. However,
percolation test results can significantly vary laterally and vertically due to shght changes in soil
type, degree of weathering, secondary mineralization, and other physical and chemical variabilities.
As such, the test results are considered to be an estimate of percolation and converted infiltration
rates for design purposes. No guarantee is made based on the percolation testing related to the actual
fimctionality or longevity of associated BMP devices designed fiom the presented infiltration rates.
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4.0 GEOLOGY
4.1 General Setting
Carlsbad is located within the Peninsular Ranges physiographic province that is characterized by
northwest-trending mountain ranges, intervening valleys, and predominantly northwest trending
regional faults. The greater San Diego Region can be further subdivided into the coastal plain area,
a central mountaine-valley area and the eastern mountain valley area. The site is located on the
western margin of the central moxmtain valley area that is characterized by a locally eroded
basement surface consisting of Jurassic and Cretaceous crystalline rocks.
4.2 Geologic Conditions
Regional geologic mapping by Keimedy and Tan (2007) indicates the near surface geologic unit
underlying the site consists of imdivided Metasedimentary and Metavolcanic rock. Based on the
recent reconnaissance and site explorations. Quaternary Previously Placed Fill and Residual Soil
were encovmtered at the surface with the Metasedimentary and Metavolcanic rock at depth
throughout the site. Descriptions of the geologic units encoimtered are presented below.
4.2.1 Quatemarv Previouslv Placed Fill (Oppf)
Quaternary Previously Placed Fill was observed on the eastern portion of the site. This unit
generally consists of loose to medium dense, sUty to clayey fine to medium grained sand
with gravel. This fill unit appears to support the existing Bolero Street improvements.
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4.2.2 Residual Soil (unmapped")
Residual Soil was observed at the surface in aU the explorations. This iinit generally consists
of medium dense, silty to clayey fine grained sand with angular gravel. This unit is
relatively thin and blankets the imderlying Metasedimentary and Metavolcanic rock.
4.2.3 Metasedimentarv and Metavolcanic Rocks Undivided (Mzul
Undivided Metasedimentary and Metavolcanic rock was observed at depth throughout the
site. Where encountered, this bedrock unit consists of very dense, reddish brown, clayey
fine grained sandstone and metavolcanic rock.
4.3 Grotmdwater Conditions
During the recent investigation, groundwater was not encountered in the exploratory borings, which
were advanced to a maximum ejqilored depth of approximately 11 feet bgs. While groundwater
conditions may vary, especially during or foUowing periods of sustained precipitation or irrigation, it
is generally not anticipated to affect the proposed construction activities or the completed
improvements, if proper site drainage is designed, installed, and maintained as per the
recommendations of the project civil engineer.
4.4 Geologic Hazards
Geologic hazards that were considered to have potential impacts to site development were evaluated
based on field observations, literature review, and laboratory test results. It spears that geologic
hazards at the site are primarily limited to those caused by shaking fixim earthquake-generated
ground motions. The foUowing paragraphs discuss the geologic hazards considered and their
potential risk to the site.
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4.4.1 Surface Fault Rupture
Based on reconnaissance and review of referenced literature, the site is not within a State of
California-designated Alquist-Priolo Earthquake Fault Studies Zone, and no known active
fault traces underlie or project toward the site. According to the California Division of
Mines and Geology, a fault is active if it displays evidence of activity in the last 11,000 years
(Hart and Bryant, revised 2007). Therefore, the potential for smface rupture from
displacement or fault movement beneath the proposed improvements is considered to be low.
4.4.2 Local and Regional Faulting
The California Geological Survey (CGS) and the United States Geological Survey (USGS)
broadly group faults as "Class A" or "Class B" (Cao, 2003; Frankel et al., 2002). Class A
faults are identified based upon relatively well-defined paleoseismic activity, and a fault-slip
rate of more than 5 millimeters per year (mm/yr). In contrast. Class B fruits have
comparatively less defined paleoseismic activity and are considered to have a fault-slip rate
less than 5 mm/yr. The nearest known Class B fault is the Rose Canyon Fault, which is
located approximately 11.4 kilometers west of the site (Blake, T.F., 2000). The nearest
known Class A fault is the JuUan segment of the Elsinore Fault that is located approximately
38.0 kilometers northeast of the site.
4.4.3 Liquefrction and Seismic Settlement Evaluation
Liquefaction occurs when saturated fine-grained sands or silts lose their physical strengths
during earthquake-induced shaking and behave like a liquid. This is due to loss of
point-to-point grain contact and transfer of normal stress to the pore water. Liquefaction
potential varies with water level, soil type, material gradation, relative density and probable
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intensity and duration of ground shaking. Seismic settlement can occur with or without
liquefaction and results from densification of loose soUs.
The site is underlain at relatively shallow depths by dense to very dense bedrock and the
relatively loose near-surface soUs are to be overexcavated and recompacted beneath
proposed improvement areas, as recommended herein. Therefore, the potential for
hquefection or significant seismic settlement at the site is considered to be neghgible.
4.4.4 Tsunamis and Seiche Evaluation
According to http://www.conservation.ca.gov/cgs/geologic_hazards/Tsunami/lnimdation
Maps/Pages/Statewide_Maps.aspx the site is not located within a tsunami inundation zone
based on its elevation above sea level. Damage resulting from oscillatory waves (seiches) is
considered unlikely due to the absence of large nearby confined bodies of water.
4.4.5 Landsliding
According to mapping by Tan (1995), the site is considered only "Generally Susceptible" to
landshding and no landslides are mapped in the site area. In addition, landshdes or similar
associated features were not observed during the recent field exploration. Based on the
investigation findings, landsliding is not considered to be a significant geologic hazard at the
subject site.
4.4.6 Compressible and Expansive Soils
Based on observations and testing, the existing near-surfrce residual soils and imdocumented
fills, if encountered, are considered to be potentially compressible. Therefore, it is
recommended that these soUs be overexcavated to the depth of competent underlying
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material ^d properly re-compacted as recommended herein. Based on the site observations
and experience with similar soUs in the vicinity ofthe site, the underlying bedrock unit is not
anticipated to be subject to significant compressibility under the proposed loads.
Based on site observation and material properties, soils at the site are anticipated to exhibit
Medium expansion potential (with Expansion Index of generally 70 or less).
Recommendations presented herein are intended to reduce the potential adverse impacts of
medium expansion soils. Additional evaluation of potential expansive soU conditions may
be conducted during grading to confirm that the soils encountered or placed as compacted
fill are as anticipated.
4.4.7 Corrosive SoUs
Testing of representative site soils was performed to evaluate the potential corrosive effects
on concrete foimdations and buried metallic utilities. Soil environments detrimental to
concrete generally have elevated levels of soluble sulfates and/or pH levels less than 5.5.
According to the American Concrete Institute (ACl) Table 318 4.3.1, specific guidelines
have been provided for concrete where concentrations of soluble sulfate (SO4) in soil exceed
0.10 percent by weight These guidelines include low water/cement ratios, increased
compressive strength, and specific cement-type requirements. A minimum resistivity value
less than approximately 5,000 ohm-cm and/or soluble chloride levels in excess of200 ppm
generally indicate a corrosive environment for buried metallic utilities and untreated
conduits.
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Chemical test results indicate that near-surface soils at the site present a low corrosion
potential for Portland cement concrete. As such, the use of Type-ll cement should be
adequate for structural site concrete. Based on resistivity testing, the site soils have been
interpreted to have a severe corrosivity potential to buried metallic improvements.
Therefore, it would likely be prudent for buried utilities to, at a minirrmm, utilize plastic
piping and/or conduits, where feasible. It should be noted that CTE does not practice
corrosion engineering. Therefore, if corrosion of improvements is of more significant
concern, a qualified corrosion engineer could be consulted.
5.0 CONCLUSIONS AND RECOMMENDATIONS
5.1 General
CTE concludes that the proposed development of the site is feasible fix)m a geotechnical standpoint,
provided the recommendations in this report are incorporated into the design and construction of the
project Recommendations for the proposed earthwork and improvements are included in the
foUowing sections and Appendix D. However, recommendations in the text of this report supersede
those presented in Appendix D should variations exist. These recommendations should either be
confirmed as appropriate or updated based on actual conditions exposed following demolition or
during earthwork operations at the site.
5.2 Site Preparation
Prior to grading, the proposed improvement areas should be cleared of existing debris and
deleterious materials. Debris, vegetation and other materials not suitable for structural backfill
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should be properly disposed of off-site. In areas to receive structures, existing loose or disturbed
soils should be removed to the depth of competent dense native material. In order to provide
uniform conditions under proposed structures, overexcavation should extend to a minimum depth of
two feet below proposed foimdations, to the depth of competent native materials, or 1/3 the
maximum depth of fill beneath the structure, whichever is deepest. Where feasible, overexcavation
should extend laterally at least five feet beyond the limits of the proposed improvements or a
distance equaling the depth of fill (1:1 from bottom of footing), whichever is greater. Actual lateral
removal limits should be evaluated during construction based on exposed conditions.
As an alternative to performing the overexcavations recommended herein, or if the proposed
structure wiU utidize a basement or deepened foundations, all foundations may be deepened to bear
entirely within competent dense native materials. Should foundations on native materials be
optioned, overexcavation beneath the proposed building need only extend to competent native
materials and a minimum 12 inches beneath all slab-on-grade materials, whichever is deeper.
If proposed, excavations in pavement or flatwork areas should be conducted to a minimum depth of
two feet below proposed subgrade, or to the depth of suitable underlying materials, whichever depth
is shallower.
Prior to placement of fiU, overexcavation areas should be approved by a CTE geotechnical
representative in order to verify the presence of suitable underlying material.
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Existing below-ground utilities should be redirected around the proposed structure. Abandoned
pipes exposed by grading should be securely capped to prevent moisture Sum migrating beneath
foundation and slab soils or should be filled with minimum two-sack cement/sand slurry.
A CTE geotechnical representative should observe the exposed ground surfaces at the
overexcavation bottom to evaluate the exposed conditions. The exposed subgrades to receive fill
should be scarified a minimum of eight inches, moisture conditioned to a minimum of three percent
above optimum, and properly compacted prior to additional fill placement based upon
recommendations of CTE's field representative.
5.3 Site Excavation
Generally, excavation of site materials may be accomplished with heavy-duty construction
equipment under normal conditions; however, the underlying weathered bedrock wiU become
increasingly difficult to excavate with depth and deeper excavations may not be feasible with
standard heavy-duty equipment Therefore, if deep excavations are proposed, some specialized rock
breaking or excavation equipment use could be required. Though not generally anticipated, large
hard and dense "core stones" could also be encoimtered in weathered bedrock masses resulting in
localized, very difficult to impenetrable excavation conditions.
5.4 Fill Placement and Compaction
Following recommended overexcavation of loose or disturbed soils, the areas to receive fills or
improvements should be scarified a minimum of eight inches, moisture conditioned, and properly
compacted. Fill and backfill should be compacted to a minimum relative compaction of 90 percent
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at a moisture content of at least three percent above optimum as evaluated by ASTM D 1557. The
optimum lift thickness for fiU soil wUl depend on the t)^ of compaction equipment used.
Generally, backfill should be placed in uniform, horizontal lifts not exceeding eight inches in loose
thickness. Fill placement and compaction should be conducted in conformance with local
ordinances.
5.5 Fill Materials
Properly moisture-conditioned low to medium expansion potential soils derived fiom the on-site
excavations are anticipated to be suitable for reuse on the site as compacted fiU. Irreducible
materials greater than three inches in maximum dimension generally should not be used in shallow
fills (within three feet of proposed grades). In utility trenches, adequate bedding should surround
pipes.
Imported fill beneath structures, flatwork, and pavements should have an Expansion Index of 30 or
less (ASTM D 4829). Imported fill soils for use in structural or slope areas should be evaluated by
the soils engmeer before being imported to the site.
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Retaining wall backfill located within a 45-degree wedge extending up fi-om the heel of the wall
should consist of soil having an Expansion Index of 30 or less (ASTM D 4829) with less than 30
percent passing the No. 200 sieve. The upper 12 to 18 inches of waU backfiU should consist of
lower permeability soils, in order to reduce surface water infiltration behind walls. The project
stractural engineer and/or architect should detail proper waU backdrains, including gravel drain
zones, fills, filter fabric, and perforated drain pipes.
5.6 Temporarv Construction Slopes
The following recommended slopes should be relatively stable against deep-seated failure, but may
experience localized sloughing. On-site soils are considered Type B and Type C soils with
recommended slope ratios as set forth in the table below.
TABLE 5.6
RECOMMENDED TEMPORARY SLOPE RATIOS
SOIL TYPE SLOPE RATIO
(Horizontal: vertical)MAXIMUM HEIGHT
B (Weathered Metavolcanic and
Metasedimentary rock)1:1 (OR FLATTER)10 Feet
C (Previously Place Fill and
Residual Soil)1.5:1 (OR FLATTER)5 Feet
In general, the above temporary slopes are anticipated to be appropriate above a maximum four-foot
taU vertical excavation. However, actual field conditions and soU type designations must be verified
by a "competent person" while excavations exist, according to Cal-OSHA regulations. In addition,
the above sloping recommendations do not allow for surcharge loading at the top of slopes by
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vehicular traffic, equipment or materials. Appropriate surcharge setbacks must be maintained from
the top of all unshored slopes.
5.7 Construction Shoring
If construction shoring is required or desired, a typical soldier beam and lagging shoring system is
anticipated to be suitable for the subject site. However CTE can provide alternative shoring system
recommendations if deemed necessary by the design/construction team. It should be noted that if
shoring improvements are to extend to significant depths, excavation or drilling into dense
formational materials could be difficult and/or impractical with standard- or even heavy duty
equipment.
Active or at-rest pressures provided herein may be used for design of permanent shoring.
Temporary shoring design may be based on the active or at-rest pressures provided herein, but may
be reduced by 30 percent as they are not for permanent use.
For conventional soldier beam and lagging shoring systems, soldier beams, spaced at least three
diameters on center, may be designed using an allowable passive pressure of 400 psf per foot of
depth, up to a maximum of 6,000 psf, for the portion of the soldier beam embedded in eompetent
dense to very dense formational materials and below the bottom of the proposed excavations. The
passive pressure may be assumed to be applied over a distance equal to twice the diameter of the
roimded or drilled soldier beam element. However, provisions should be made to assure firm
contact between the beam and the surrounding soils. Concrete placed in soldier beams below the
proposed excavation should have adequate strength to transfer the imposed pressures. A lean
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concrete mix may be used ia the soldier pile above the base of the proposed excavation. Soldier
beam installations should be observed by CTE.
Due to the locally erodible nature of onsite materials, continuous timber or precast concrete lagging
between soldier beams is recommended. Lagging should be designed for the recommended earth
pressures but be limited to a maximum pressure of400 psf due to arching in the sods. Voids created
behind lagging by sloughing of locally eohesionless soU layers shall be grouted or slurry filled, as
feasible. In addition, generally the upper two to four feet of lagging shall be grouted or slurry-filled
to assist in diverting surfece water jfrom migrating behind the shoring walls. Adequate surface
protection fix)m drainage should be maintained at all times.
Monitoring of settlement and horizontal movement of the shoring system and adjacent
improvements should occur on a weekly basis during construction in order to confirm that actual
movements are within tolerable limits. The number and location of monitoring points shall be
indicated on the shoring plans; CTE will review such locations and the proposed monitoring
schedule once prepared and provided by the shoring contractor.
Additional shoring recommendations can be provided in an update geotechnical report(s), to be
submitted imder separate cover as grading and structural plans are developed, and if necessary.
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5.8 Foundation and Slab Recommendations
The following recommendations are for preliminary design purposes only. These recommendations
should be reviewed after completion of earthwork to document that conditions exposed are as
anticipated and that the recommoided structure design parameters are appropriate. Foundations
should not transition from cut to compacted fill materials. Therefore, once proposed plans are more
developed, these recommendations should be reviewed and updated as appropriate to determine if all
foundations will bear entirely in compacted fill soils (prepared as recommended herein), or if all
foundations will be deepened to bear entirely in competent dense formational materials as
recommended herein.
5.8.1 Foundations
Continuous and isolated spread footings are anticipated to be suitable for use at this site. It is
anticipated that the proposed footings wfil either be founded entirely on at least 24 inches of
properly compacted fill placed as recommended herein or entirely on dense bedrock
materials. If deeper footings are proposed, additional overexcavation and compaction may
be recommended in order to provide a minimum of 24 inches of fill beneath aU foundation
elements, or aU footings can be deepened to bear entirely upon competent dense native
materials. As indicated herein, footings should not straddle cut-fill interfaces.
Foxmdation dimensions and reinforcement should be based on an allowable bearing value of
2,500 povmds per square foot (psf) for footings founded entirely in suitable fill materials, or
3,500 psf for footings founded entirely in dense native materials. Footings should also be
embedded a minimum of 24 inches below the lowest adjacent rough subgrade elevation. If
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December 30,2016 CTEJobNo. 10-13435G
utilized, continuous footings should be at least 15 inches wide; isolated footings should be at
least 24 inches in least dimension. If deepened spread or pier footings are proposed, the
bearing value may be increased by 250 psf for each additional six inches of embedment up to
a maximum static value of 3,000 psf for footings embedded in competent fill materials or
4,000 psf for footings embedded entirely in competent dense native materials. The above
bearing values may also be increased by one third for short duration loading which includes
the effects of wind or seismic forces.
Minimum footing reinforcement for continuous footings should consist of four No. 4
reinforcing bars; two placed near the top and two placed near the bottom, or as per the
project structural engineer. The structural engineer should design isolated footing
reinforcement Footing excavations should generally be maintained above optimum
moisture content until concrete placement If materials are allowed to desiccate, presoaldng
may be required.
5.8.2 Foundation Settlement
The maximum total static settlement is expected to be on the order of one inch and the
maximum differential static settlement is expected to be on the order of 1/2 inch over a
distance of approximately 40 feet. Based on the noted site conditions, dynamic settlement is
not expected to adversely affect the proposed improvements.
5.8.3 Formdation Setback
Footings for structures should be designed such that the horizontal distance from the face of
adjacent slopes to the outer edge of the footing is at least 15 feet In addition, footings
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should bear beneath a 1:1 plane extended up from the nearest bottom edge of adjacent
trenches and/or excavations. Deepening of affected footings may be a suitable means of
attaining the prescribed setbacks.
5.8.4 Interior Concrete Slabs
Lightly loaded concrete slabs should be a minimum of five inches thick. Minimum slab
reinforcement should consist of #4 reinforcing bars placed on maximum 18-inch centers each
way, at above mid-slab height, but with proper cover. Slabs subjected to heavier loads may
require thicker slab sections and/or increased reinforcement. Subgrade materials should be
maintained above optimum moisture content until slab imderlayment or concrete are placed.
Subgrade soils should be at least three percent over optimum moisture content just prior to
concrete or imderlayment placement. If materials are allowed to desiccate, presoaking may
be required.
In moisture-sensitive floor areas, a suitable vapor retarder of at least 15-mil thickness (with
all laps or penetrations sealed or taped) overlying a four-inch layer of consohdated minimum
/4-inch crushed aggregate gravel should be installed per the current building code. An
optional maximum two-inch layer of similar aggregate material may be placed above the
v^x)r retarder to further protect the membrane during steel and concrete placement, if
desired. However, best performance with respect to minimizing moisture intrusion is
anticipated to result via placement of concrete directly upon the vapor retarder. These
recommended moisture protections are generally considered typical of the area. However,
CTE is not an expert at preventing moisture penetration through slabs. If proposed floor
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Geotechnical Investigation Page 20
Proposed Dempsey Residence
APN: 215-491-36-00, Bolero Street, California
December 30, 2016 CTE JobNo. 10-13435G
areas or coverings are considered especially sensitive to moisture emissions, additional
recommendations from a specialty consultant could be obtained. A qualified architect or
other experienced professional should be contacted if moisture penetration is a more
significant concem.
5.9 Seismic Design Criteria
The seismic ground motion values listed in the table below were derived m accordance with the
ASCE 7-10 Standard. This was accomplished by establishing the Site Class based on the soU
properties at the site, and then calculating the site coefficients and parameters using the United
States Geological Survey Seismic Design Maps apphcation for the 2013 and 2016 CBC values.
These values are intended for the design of structures to resist the effects of earthquake groimd
motions for the site located at coordinates 33.0967°N latitude and -117.2456°W longitude, as
underlain by soils corresponding to site Class C.
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December 30, 2016
Page 21
CTE JobNo. 10-13435G
TABLE 5.9
SEISMIC GROUND MOTION VALUES
PARAMETER VALUE CBC REFERENCE (2013)
She Class C ASCE 7, Chapter 20
Mapped Spectral Response
AccelCTation Parameter, Ss 1.034 Figure 1613.3.1 (1)
Mapped Spectral Response
Acceleration Parameter, Si 0.400 Figure 1613.3.1 (2)
Seismic Coefficient, F,1.000 Table 1613.3.3 (1)
Seismic Coefficioit, Fy 1.400 Table 1613.3.3 (2)
MCE Spectral Response
Acceleration Parameter, Sms 1.034 Section 1613.33
MCE Spectral Response
Acceleration Parameter, Smi 0.560 Section 1613.3.3
Design Spectral Response
Acceleration, Parameter Sds 0.689 Secticm 1613.3.4
Design Spectral Response
Acceleration, Parameter Sdi 0.374 Section 1613.3.4
Peak Ground Accelaation PGAm 0.399 ASCE 7, Section 11.8.3
5.10 Lateral Resistance and Earth Pressures
Lateral loads acting against structures may be resisted by friction between the footings and the
supporting soil or passive pressure acting against structures. If frictional resistance is used, CTE
recommends an allowable friction coefficient of 0.30 (total frictional resistance equals the
coefficient of friction multiplied hy the dead load) for concrete cast directly against compacted fill.
A design passive resistance value of250 pormds per square foot p>er foot of depth (with a maximum
value of2,000 pounds per square foot) may be used. The allowable lateral resistance can be taken as
the sum of the fiictional resistance and the passive resistance, provided the passive resistance does
not exceed two-thirds of the total allowable resistance.
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December 30, 2016
Page 22
CTE JobNo. 10-13435G
Retaining waUs backfilled using granular very low expansion soils may be designed using the
equivalent fiuid weights given in Table 5.10 below.
TABLE 5.10
EQUIVALENT FLUID UNIT WEIGHTS
(pounds per cubic foot)
WALL TYPE LEVEL BACKFILL
SLOPE BACKFILL
2:1 (HORIZONTAL:
VERTICAL)
CANTILEVER WALL
(YIELDING)35 55
RESTRAINED WALL 55 65
1
Lateral pressures on cantilever retaining waUs (yielding walls) due to earthquake motions may be
calculated based on work by Seed and Whitman (1970). The total lateral thrust against a properly
drained and backfilled cantilever retaining wall above the groimdwater level can be expressed as:
Pae = Pa + APae
For non-yielding (or "restrained") walls, the total lateral thrust may be similarly calculated
based on work by Wood (1973):
Pre = Pk + APke
Where Pa = Static Active Thrust (given previously Table 5.10)
Pk = Static Restrained Wall Thrust (given previously Table 5.10)
APae = Dynamic Active Thrust Increment = (3/8) k),
APke = Dynamic Restrained Thrust Increment = kh yH
kh = 2/3 Peak Ground Acceleration = 2/3 (PGAm)
H = Total Height of the Wall
y = Total Unit Weight of Soil -135 pounds per cubic foot
The increment of dynamic thrust in both cases should be distributed triangxilarly with a line of action
located at H/3 above the bottom of the wall (SEAOC, 2013).
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December 30,2016 CTE JobNo. 10-13435G
These values assume non-expansive backfill and firee-draining conditions. Measures should be taken
to prevent moisture buildup behind all retaining walls. Drainage measures should include fi^e-
draining backfill materials and sloped, perforated drains. These drains should discharge to an
qjpropriate ofif-site location. The project structural engineer and/or architect should design the
appropriate retaining wall drainage details. Waterproofing should be as specified by the project
architect or the waterproofing specialty consultant.
5.11 Exterior Flatwork
To reduce the potential for cracking in exterior flatwork caused by minor movement of subgrade
soils and typical concrete shrinkage, it is recommended that such flatwork be installed with crack-
control joints at appropriate spacing as designed by the project architect and measure a minimum
five inches in thickness. Additionally, it is recommended that flatwork be installed with at least
number 4 reinforcing bars on maximum 18-inch centers, each way, at above mid-height of slab but
with proper concrete cover, or other reinforcement per the project consultants. Flatworic, which
should be installed with crack control joints, includes sidewalks, and architectural features.
Doweling of flatwork joints at critical pathways or similar could also be beneficial in resisting minor
subgrade movements.
All subgrades should be prepared according to the earthwork recommendations previously given
before placing concrete. Positive drainage should be established and maintained next to all fiatworic
Subgrade materials shall be maintained at, or be elevated to, above optimum moisture content prior
to concrete placement
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December 30, 2016 CTEJobNo. 10-134350
5.12 Drainage
Surface runoff should be collected and directed away from improvements by means of appropriate
erosion-reducing devices, and positive drainage should be established around proposed
improvements. Positive drainage should be directed away from improvements and slope areas at a
minimum gradient of two percent for a distance of at least five feet. However, the project civil
engineer should evaluate the on-site drainage and make necessary provisions to keep surface water
from affecting the site.
Generally, GTE recommends against allowing water to infiltrate building pads or adjacent to slopes
and improvements. However, it is understood that some agencies are encouraging the use of storm-
water cleansing devices. Therefore, if storm water cleansing devices must be used, it is
recommended that they be underlain by an impervious barrier and that the infiltrate be collected via
subsurface piping and discharged off site. If infiltration must occur, water should infiltrate as far
away from structural improvements as feasible. Additionally, any reconstructed slopes descending
from infiltration basins should be equipped with subdrains to collect and discharge accumulated
subsurface water (Appendix D contains details for internal fill slope drainage).
5.13 Slopes
Based on anticipated soil strength characteristics, cut and fill slopes should be constructed at slope
ratios of 2:1 (horizontal: vertical) or flatter. These fill slope inclinations should exhibit gross
stability factors of safety greater than 1.5.
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Proposed Dempsey Residence
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December 30,2016 CTEJobNo. 10-13435G
Although properly constructed slopes on this site should be grossly stable, the soils will be
somewhat erodible. Therefore, runoff water should not be permitted to drain over the edges of
slopes unless that water is confined to properly designed and constructed drainage facilities.
Erosion-resistant vegetation should be maintained on the face of all slopes. Typically, soils along
the top portion of a fill slope face will creep laterally. CTE recommends against building distress-
sensitive improvements within five feet of slope crests.
5.14 Plan Review
CTE should be authorized to review the project grading, shoring, and foundation plans (as
applicable) before commencement of earthwork for a comparison with the intent of the
recommendations provided.
5.15 Construction Observation
The recommendations provided in this report are based on preliminary design information for the
proposed construction and the subsurface conditions observed in the exploratory borings. The
interpolated subsurface conditions should be checked in the field during construction to document
that conditions are as anticipated. Upon completion of rough grading, soil san^les may be collected
to evaluate as-buUt Expansion Index of near-grade soils. Foundation and other recommendations
may be revised upon completion of grading, and as-built laboratory test results.
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December 30,2016 GTE Job No. 10-13435G
Recommendations provided in this report are based on the understanding and assumption that CTE
will provide the observation and testing services for the project. Earthwork should be observed and
tested to document that grading activity has been performed according to the recommendations
contained widiin this report A CTE representative should evaluate all footing trenches before
reinforcing steel placement.
6.0 LIMITATIONS OF INVESTIGATION
The field evaluation, laboratory testing, and geotechnical analysis presented in this report have been
conducted according to current engineering practice and the standard of care exercised by reputable
geotechnical consultants performing similar tasks in this area. No other warranty, expressed or
implied, is made regarding the conclusions, recommendations and opinions expressed in this report
Variations may exist and conditions not observed or described in this report may be encoimtered
during construction.
The recommendations provided herein have been developed in order to reduce the potential adverse
impacts of expansive site soils and differential bearing conditions associated with hillside grading
and development However, even with the design and construction precautions herein, some post-
construction movement and associated distress could occur and should be anticipated.
The findings of this report are vahd as of the present date. However, changes in the conditions of a
property can occur with the passage of time, whether they are due to natural processes or the works
of man on this or adjacent properties. In addition, changes in applicable or ^propriate standards
may occur, whether they result fium legislation or the broadening of knowledge. Accordingly, the
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December 30, 2016
Page 27
GTE Job No. 10-134350
findings of this report may be invalidated wholly or partially by changes outside our control.
Therefore, this report is subject to review and should not be relied upon after a period of three years.
CTE's conclusions and recommendations are based on an analysis of the observed conditions. If
conditions different from those described in this report are encountered, this office should be notified
and additional recommendations, if required, will be provided.
We appreciate this opportunity to be of service on this project. If you have any questions regarding
this report, please do not hesitate to contact the undersigned.
Respectfully submitted,
CONSTRUCTION TESTING & ENGINEERING, INC.
^Math, GE #2665
Principal Engineer
/id F/L^ich, CEG #1890
Pnriieipal Engineering Geologist
certifiedengineering
/
Colm J. Kenny, RCE #84406
Project Engineer
AJB/CJKyjFL/DTM:nri
Aafgh'J. Beeby, CEG #2603
Project (*ologist
cerhfied
ERING
CLOGIST
\\Esc_scn'er\projects\10-I3435G\RpLGeotechnical (5-17).doc
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an Gn^
Noodlts &
Cotvpary
f
^0.'/i.*^0
ci^ Construction Testing & Engineering, Inc.1441 MonM Rd Ste 115, Eaconddo. CA 92026 Ph (780) 746-4B5S
SITE INDEX MAP
PROPOSED DEHPSEY RESIDENCE
APN: 215-401-36-00. BOLERO STREET
CAR1£BAD. CAUFORNU
SCALE:
AS SHOWN
CTE JOB NO.:
10-13435G
DATE:
12/16
HGURE:
1
r
B-3 Approximate Boring Location
P-3 Approximate Percolation Test Location
Qppf Quaternary Previously Placed Fill
MZU Metasedlmentary and Metavolcanic Rock
^ ^ ^ ^ Approximate Geologic Contact
Construction Testing & Engineering, Inc.CTE Inc.1441 Montiel Rd Ste 115. Escondido. OA 92026 Ph {760) 746-4955
6SOLOGIC/KZPLOIUT10N LOCATION MAP
PROPOSED DEUPSEY RESIDENCE
APN: 215-491-36-00. BOIZRO STREFT
CARISBAD, CAUPORNU
SCALE:
r=5o*
CTE JOB NO.:
10-134356
DATE:
12/16
nOURE:
2
12 12
LEGEND
1 Inch = 12 ml.
fit ■■• '«
•Wwcr
j»f^
HISTORIC FAULT DISPLACEMENT (LAST 200 YEARS)
-A. HOLOCENE FAULT DISPLACEMENT (DURING PAST 11.700 YEARS)
—fc. LATE QUATERNARY FAULT DISPLACMENT (DURING PAST 700,000 YEARS)
g^ai. " Icn^K
It 0^1 V
nn -X , "V C^ \ \ . v\
U)
o:
cr/;
%..A. QUATERNARY FAULT DISPLACEMENT (AGE UNDIFFERENTIATED)
....A.
y-j IV
PREQUATERNARY FAULT DISPLACEMENT (OLDER THAN 1.6 MILLION YEARS)
PERIOD 1800-
1868
1869-
1931
193
'ii''
:X-fl^.4.1 \M'
\
.'-'0..S I
y.
/r-■ .'CMeoty
.^•
%
<h
?c i \
/. 1
%LU.^1 Q
D1-
2."Ml O<
2-
2010
> 7.0
i-iii
r*->-
X N ^ . J\ \ \\ -.v^Vx; '
\ '. ' I APPROXIMATE^ V. A xJ SITE LOCATION t
\\ \ \
Xa ^CvVv \ \)\ ®ii'v \\\
i\
<4^
~\~
4A.
rad ;<V ■*'K V/J
'f V
y-It' K Mfo
LAST TWO DIGITS OF M > 6.5
EARTHQUAKE YEAR
AX \yv v;;
w_A
-
1%'■W19S ;/^-
"VatfLi
Ai'■ - ■X x:
T ■f,''V-
A>X-
M
R I
:.i^'
'J//
V^OTES: FAULT ACTIVITY HAP OF CAUFORNIA, 2010. CAUFORNU GEOLOGIC DATA MAP SERIES MAP NO. 6;
EPICENTERS OF AND AREAS DAMAGED BY 1<>5 CAUFORNU EARTHQUAKES, 1800-1M9 ADAPTEDAfTER TOPPOZADA, BRANUM. PETERSEN, HAUkORM, CRAMER, AND REICHlf. 2000,
CDMG MAP SHEET 40
REFERENCE FOR ADDITIONAL EXPLANATION: MODIFIED WITH CISN AND USGS SEISMIC MAPS
\
' hi ^ ' ■
Construction Testing & Engineering, Inc.
1441 ManM Rd 8te 115, Escondkjo, OA 92026 Ph (760)7404955
REGIONAL FAULT AND SEISMICnY MAP
PROPOSED DEMPSEY RESIDENCEAPN: 215-491-36-00, BOLERO STREETCARLSBAD. cAUFORNU
IRJBHB:10-13435G
scant —
1 inch = 12 miles
ineuc:It , ir12/16 I
12" TO 18" OF LOWER
PERMEABILITY NATIVE
MATERIAL COMPACTED TO 90%
RELATIVE COMPACTION
RETAINING WALL-
FINISH GRADE
TO BE
Y ARCHITECT
PERFORATED PVC
::^PE (SCHEDULE 40 OR
' QUIVALENT). MINIMUM
1% GRADIENT TO SUITABLE
OUTLET
WALL FOOTING
Construction Testing & Engineering . Inc.Ole M:1441 Montie) Ra Ste 115. EsconOido, OA 92026 P^ (760) 746^955
RETAINING WALL DRAINAGE DETAIL
en- JOH \'o
10-13435G
SCALI"
NO SCALE
IlATi; MGI Ki .
12/16 4
; APPENDIX A
i ! n ' . n " '
REFERENCES
REFERENCES
1. ASTM, 2002, "Te^ Method for Laboratory Compaction Characteristics of Soil Using
Modified Effort," Volume 04.08
2. Blake, T.F., 2000, "EQFAULT," Version 3.00b, Thomas F. Blake Computer Services and
Software.
3. California Building Code, 2013, "California Code of Regulations, Title 24, Part 2, Volume 2
of 2," California: Building Standards Commission, published by ICBO, Jvme.
4. California Division of Mines and Geology, CD 2000-003 "Digitd Images of Official Maps
of Alquist-Priolp Earthquake Fault ^hes of California, Southern Region," compiled by
Martin and Ross.
5. Frankel, A;D., Petersen, M.D., MueUer, C.S., Haller, K.M., Wheeler, R.L., Leyendecker,
E.V., Wesson, ILL. Harmsen, S.C., Criamer, C.H., Perkins, D.M., and Rukstales, K.S., 2002,
Documentation for the 2002 update of the National Seismic Hazard M^s: U.S. Geological
Survey Open-File Report 02-420, 33 p.
6. Hart, Earl W., and Bryant, William A., Revised 2007, "Fault-Rupture Hazard Zones in
California, Alquist Priolo, Special Studies Zones Act of 1972," California Division of Mines
and Geology, Special Publication 42.
7. Jennings, Charles W., 1994, "Fault Activity Map of California and Adjacent Areas" with
Locations and Ages of Recent Volcanic Eruptions.
8. Keimedy, M.P. and Tan, S.S., 2007, "Geologic M^ of the Oceanside 30' x 60' Quadrangle,
California", California Geological Survey, M^ No. 2, Plate 1 of 2.
9. SEAOC, Blue Book-Seismic Design Recommendations, "Seismically Induced Lateral Earth
Pressures on Retaining Structures and Basement Walls," Article 09.10.010, October 2013.
10. Seed, H.B., and KV. Whitman, 1970, "Design of Earth Retaining Structures for Dynamic
Loads," in Proceedings, ASCE Specialty Conference on Lateral Stresses in the Ground and
Design of Earth-Retaining iStructures, pp. 103-147, Ithaca, New York: Cornell University.
11. Tan, Siang S. and Giffen, Desmond G., 1995, "Landslide Hazards in the Northern Part of
The San Diego Metropolitan Area, San Diego County, California, Rancho Santa Fe
Quadrangle (Plate E), DMG Open-File Report 95-04, Plate; 35E.
12. Wood, J.H. 1973, "Earthquake-Induced Soil Pressures on Structures," Report EERL 73-05.
Pasadena; California Institute of Technology.
APPENDIX B
EXPLORATION LOGS
Inc.
Construction Testing & Engineering, Inc.
1441 Montiel Rd Ste 115, Escondido, CA 92026 Ph (760) 746-4955
DEFINITION OF TERMS
PRIMARY DIVISIONS SYMBOLS SECONDARY DIVISIONS
(0 <du.E
CO u. —
5Z§liJ
Uj lij < CM
5|£i8^1
GRAVELS
MORE THAN
HALF OF
COARSE
FRACTION IS
LARGER THAN
NO. 4 SIEVE
SANDS
MORE THAN
HALF OF
COARSE
FRACTION IS
SMALLER THAN
NO. 4 SIEVE
CLEAN
GRAVELS
<5% FINES
GRAVELS
WITH FINES
3ST 15?ji^ GW }^>o
GP
WELL GRADED GRAVELS. GRAVEL-SAND MIXTURES
LITTLE OR NO FINES
POORLY GRADED GRAVELS OR GRAVEL SAND MIXTURES.
LITTLE OF NO FINES
SILTY GRAVELS. GRAVEL-SAND-SILT MIXTURES.
NON-PLASTIC FINES
CLAYEY GRAVELS, GRAVEL-SAND-CLAY MIXTURES.
PLASTIC FINES
CLEAN
SANDS
< 5% FINES
WELL GRADED SANDS. GRAVELLY SANDS, LTTTLE OR NO
FINES
SP POORLY GRADED SANDS, GRAVELLY SANDS. LITTLE OR
NO FINES
SANDS
WITH FINES
SM SILTY SANDS, SAND-SILT MIXTURES. NON-PLASTIC FINES
»>»»
sc
CLAYEY SANDS. SAND-CLAY MIXTURES. PLASTIC FINES
3 < I o
uj a: y ^So!^ I
SILTS AND CLAYS
LIQUID LIMIT IS
LESS THAN 50
ML INORGANIC SILTS. VERY FINE SANDS. ROCK FLOUR. SILTY
OR CLAYEY FINE SANDS. SLIGHTLY PLASTIC CLAYEY SILTS
SILTS AND CLAYS
LIQUID LIMIT IS
GREATER THAN 50
OL
++++
MH
-H-
INORGANIC CLAYS OF LOW TO MEDIUM PLASTICITY.
GRAVELLY. SANDY. SILTS OR LEAN CLAYS
ORGANIC SILTS AND ORGANIC CLAYS OF LOW PLASTICITY
INORGANIC SILTS. MICACEOUS OR DLATOMACEOUS FINE
^NDY OR SILTY SOILS. ELASTIC SILTS
INORGANIC CLAYS OF HIGH PLASTICfTY, FAT CLAYS
ORGANIC CLAYS OF MEDIUM TO HIGH PLASTICITY,
ORGANIC SILTY CLAYS
HIGHLY ORGANIC SOILS PT
tamiimiui
PEAT AND OTHER HIGHLY ORGANIC SOILS
GRAIN SIZES
BOULDERS COBBLES
GRAVEL
COARSE FINE
SAND
COARSE MEDIUM FINE SILTS AND CLAYS
12" 3" 3/4"
CLEAR SQUARE SIEVE OPENING
4 10 40 200
U.S. STANDARD SIEVE SIZE
ADDITIONAL TESTS
(OTHER THAN TEST PIT AND BORING LOG COLUMN HEADINGS)
MAX- Maximum Dry Density
GS- Grain Size Distribution
SE- Sand Equivalent
El- Expansion Index
CHM- Sulfate and Chloride
Content, pH, Resistivity
COR - Corrosivity
SD- Sample Disturbed
PM- Permeability
SG- Specific Gravity
HA- Hydrometer Analysis
AL- Atterberg Limits
RV- R-Value
CN- Consolidation
CP- Collapse Potential
HC- Hydrocollapse
REM- Remolded
PP- Pocket Penetrometer
WA- Wash Analysis
DS- Direct Shear
UC- Unconfined Compression
MD- Moisture/Density
M- Moisture
SC- Swell Compression
01- Organic Impurities
FIGURE:) BLI
Inc.
Construction Testing & Engineering, Inc.
1441 Montiel Rd Ste 115, Escondido, CA 92026 Ph (760) 746-4955
PROJECT:
CTE JOB NO:
LOGGED BY:
DRILLER:
DRILL METHOD:
SAMPLE METHOD:
SHEET:
DRILLING DATE:
ELEVATION:
of
CQ
£
O
BORING LEGEND
DESCRIPTION
Laboratory Tests
-0-
-5n
-10-
-15-
20-
-25-
I
"SM"
Block or Chunk Sample
Bulk Sample
Standard Penetration Test
Modified Split-Barrel Drive Sampler (Cal Sampler)
Thin Walled Army Corp. of Engineers Sample
Groundwater Table
Soil Type or Classification Change
9 —
Formation Change [(Approximate boimdaries queried (?)1
Quotes are placed around classifications where the soils
exist in situ as bedrock
FIGURE: | BL2
Construction Testing & Engineering, Inc.
1441 Montiel Rd Ste 115, Escondido, CA 92026 Ph (760) 746-4955
PROJECT:
CTE JOB NO;
LOGGED BY:
DEMPSEY RESIDENCE
10-13435G
AJB
DRILLER:
DRILL METHOD:
SAMPLE METHOD:
BAJA EXPLORATION
HOLLOW-STEM AUGER
RING. SPT and BULK
SHEET: I of 1
DRILLING DATE: 11 /22/2016
ELEVATION: -373 FEET
- E
it >s C
CO d
&
Q o
BORING: B-1
DESCRIPTION
Laboratory Tests
-0-SM RESIDUAL SOIL:
Medium dense, dry to slightly moist, light reddish brown, silty
fine grained SAND, oxidized.
Becomes dark reddish brown
El
"SC"
-5-
-1^
19
17
14
METASEDIMENTARY AND METAVOLCANIC ROCK:
Dense, slightly moist, reddish brown, clayey fine grained
SANDSTONE with trace angular gravel, oxidized, severely
weathered.CHM
50/4"Gravel
Total Depth: 1T (Refusal on Gravel)
No Groundwater Encountered
-15-
-2<^
-25"
B-1
Inc.
Construction Testing & Engineering, Inc.
1441 Montiel Rd Ste 115, Escondido, OA 92026 Ph (760) 746-4955
PROJECT:
CTE JOB NO:
LOGGED BY:
DEMPSEV RESIDENCE
10-134350
AJB
DRILLER:
DRILL METHOD;
SAMPLE METHOD:
BAJA EXPLORATION
HOLLOW-STEM AUGER
RING. SPT and BULK
SHEET: 1 of 1
DRILLING DATE: 11 /22/2016
ELEVATION: -378 FEET
CO CQ
t-
a
g
>%
6/5
6/5
U
6/5
b o
BORING: B-2
DESCRIPTION
Laboratory Tests
-0-SM/SC RESIDUAL SOIL:
Medium dense, d^ to slightly moist, light reddish brown, silty
to clayey fine grained SAND with angular gravel, oxidized.
"SC"METASEDIMENTARY AND METAVOLCANIC ROCK:
-5-
Z
Dense, slightly moist, reddish brown, clayey fine grained
SANDSTONE with trace angular gravel, oxidized, severely
weathered.
46
50/4"
Total Depth: 8' (Refusal in Dense Formation)
No Groundwater Encountered
-10-
-15-
-20-
-25-
B-2
Inc.
Construction Testing & Engineering, Inc.
1441 Montiel Rd Ste 115, Escondido, CA 92026 Ph (760) 746-4955
PROJECT:
CTE JOB NO:
LOGGED BY;
DEMPSEV RESIDENCE
10-I3435G
AJB
DRILLER:
DRILL METHOD:
SAMPLE METHOD:
BAJA EXPLORATION
HOLLOW-STEM AUGER
RING. SPTand BULK
SHEET: I of 1
DRILLING DATE: 11 /22/2016
ELEVATION: -375 FEET
H
CQ
5
O
BORING: B-3
DESCRIPTION
Laboratory Tests
-0-SM/SC RESIDUAL SOIL:
Medium dense, dty to slightly moist, light reddish brown, silty
to clayey fine grained SAND with trace angular gravel, oxidized.
U5_
"SC"
CL
METASEDIMENTARY AND METAVOLCANIC ROCK:
Dense, slightly moist, reddish brown, clayey fine grained
SANDSTONE with trace angular gravel, oxidized, severely
weathered.
Gravel
OS
Total Depth: 8' (Refusal on Gravel)
No Groundwater Encountered
-1^
-15-
-20-
-25-
B-3
APPENDIX C
LABORATORY METHODS AND RESULTS
APPENDIX C
LABORATORY METHODS AND RESULTS
Laboratory Testing Program . ^ -
Laboratory tests were performed on representative soil samples to detect their relative engineering
properties.. Tests were performed following test rhetbods of the American Society for Testing
Materials or other accepted standaixis. The foUowing presents a brief description of the various test
methods used.
Classification
Soils were classified visually according to the Unified Soil Classification System;. Visual
classifications were supplement^ by laboratory testing of selected samples according to ASTM
D2487. The soil classifications are shown on the Exploration Logs in Appendix B.
: Expansion Index
Expansion testing was performed on selected samples of the matrix of the on-site soils according to
ASTMD4829.
Particle-Si2e Analysis
Particle-size analyses were performed on selected representative samples according to ASTM D 422.
Chemical Analysis
Soil materials were collected with sterile sampling equipment and tested for SuLfete and Chloride
content, pH, Corrosivity, and Resistivity.
Inc.
Construction Testing & Engineering, Inc.
1441 Montiel Rd Ste 115. Escondido, OA 92026 Ph (760) 746-4955
UXATION
B-1
EXPANSION INDEX TEST
ASTM D 4829
DEPTH EXPANSION INDEX
(feet)
0-5 54
EXPANSION
POTENTIAL
MEDIUM
SULFATE
LOCATION
B-1
DEPTH
(feet)
RESULTS
EE21
594.1
CHLORIDE
LOCATION DEPTH
(feet)
RESULTS
PPm
B-1 181.5
p.H.
LOCATION DEPTH
(feet)
RESULTS
B-1 7.14
LOCATION
RESISTIVITY
CALIFORNIA TEST 424
DEPTH
(feet)
RESULTS
ohms-cm
B-1 1480
LABORATORY SUMMARY CTE JOB NO. 10-13435G
100
90
80
70
£• 60
50
40
30
20
10
100
U)s
♦-r-m--«t-
00 ^
U. S. STANDARD SIEVE SIZE
<o o s 2 S 8
10 0.1
PARTICLE SIZE (mm)
0.01 0.001
PARTICLE SIZE ANALYSIS
Construction Testing & Engineering, Inc.
">'*41 Montiel Rd Ste 115. Escondido. OA 92026 Ph (760) 746-4955
Sainpli! Dcsi^ation Sample Depth (fcci)S>mbol Liquid Lunit |%)Plasiiciiv Index classifieaiioQ
B-3 5 •0 0 CL
CTE JOB NUMBER: I0-13435G nOURE: C-1
APPENDIX D
STANDARD SPECIFICATIONS FOR GRADING
Appendix D Page D-1
Standard Specifications for Grading
Section 1 - General
Construction Testing & Engmeering, Inc. presents the following standard recommaidations for
grading and other associated operations on construction projects. These guidelines should he
considered a portion of the project specifications. Recommendations contained in the body of
the previously presented soils report shall supersede the recommendations and or requirements as
specified herein. The project geotechnical consultant shall interpret disputes arising out of
interpretation of the recommendations contained in the soils report or specifications contained
herein.
Section 2 - Responsibilities of Project Personnel
The geotechnical consultant should provide observation and testing services sufficient to general
conformance with project specifications and standard grading practices. The geotechnical
consultant should report any deviations to the chent or his authorized representative.
The Ghent should be chiefly responsible for aU aspects of the project He or his authorized
representative has the responsibhity of reviewing the findings and recommendations of the
geotechnical consultant He shall authorize or cause to have authorized the Contractor and/or
other consultants to perform woric and/or provide services. During grading the Chent or his
authorized r^)resentative should remain on-site or should remain reasonably accessible to ah
concerned parties in order to make decisions necessary to maintain the flow of the project
The Contractor is responsible for the safety of the project and satisfactory complehon of ah
grading and other associated operahons on construction projects, including, but not limited to,
earth work in accordance with the project plans, specifications and controlling agency
requirements.
Section 3 - Preconstruction Meeting
A preconstruction site meeting should he arranged by the owner and/or chent and should include
the grading contractor, design engineer, geotechnical consultant, owner's representative and
representatives of the appropriate governing authorities.
Section 4 - Site Preparation
The chent or contractor should obtain the required approvals fi:x)m the controhing authorities for
the project prior, during and/or after demohtion, site preparation and removals, etc. The
appropriate approvals should he obtained prior to proceeding with grading operations.
STANDARD SPECIFICATIONS OF GRADING
Page 1 of 26
Appendix D Page D-2
Standard Specifications for Grading
Clearing and grubbing shoxild consist of the removal of vegetation such as brush, grass, woods,
stumps, trees, root of trees and otherwise deleterious natural materials fixim the areas to be
graded. Clearing and grubbing should extend to the oiitside of all proposed excavation and fill
areas.
Demohtion should include removal of buildings, structures, foundations, resavoirs, utilities
(including underground pipelines, septic tanks, leach fields, seepage pits, cisterns, mining shafts,
tunnels, etc.) and other man-made surface and subsurface improvements fix>m the areas to be
graded. Demohtion of utfiities should include proper capping and/or rerouting pipelines at the
project perimeter and cutoff and capping of weUs in accordance with the requirements of the
governing authorities and the recommendations of the geotechnical consultant at the time of
demohtion.
Trees, plants or man-made improvements not planned to be removed or demohshed should be
protected by the contractor fix)m damage or injury.
Debris generated during clearing, grubbing and/or danohtion operations should be wasted fi^m
areas to be graded and disposed off-site. Clearing, grubbing and demohtion operations should be
performed under the observation of the geotechnical consultant
Section 5 - Site Protection
Protection of the site during the period of grading should be the responsibility of the contractor.
Unless other provisions are made in writing and agreed upon among the concemed parties,
completion of a portion of the project shoiild not be considered to preclude that portion or
adjacent areas from the requirements for site protection until such time as the entire project is
complete as identified by the geotechnical consultant, the chent and the regulating agencies.
Precautions should be taken during the performance of site clearing, excavations and grading to
protect the woik site frnm flooding, ponding or inundation by poor or improper surface drainage.
Temporary provisions shoxild be made during the rainy season to adequately direct surface
drainage away frnm and off the work site. Where low areas cannot be avoided, pumps should be
kept on hand to continually remove water dming periods of rainfall.
Rain related damage should be considered to include, but may not be limited to, erosion, silting,
saturation, swelling, structural distress and other adverse conditions as determined by the
geotechnical consultant Soil adversely affected should be classified as unsuitable materials and
should be subject to overexcavation and replacement with compacted fill or other remedial
grading as recommended by the geotechnical consultant
STANDARD SPECIFICATIONS OF GRADING
Page 2 of 26
Appendix D Page D-3
Standard Specifications for Grading
The contractor should be responsible for the stability of all temporary excavations.
Recommendations by the geotechnical consultant pertaining to temporary excavations (e.g.,
badccuts) are made in consideration of stability of the completed project and, therefore, should
not be considered to preclude the responsibilities of the contractor. Recommendations by the
geotechnical consultant should not be considered to preclude requirements that are more
restrictive by the regulating agencies. The contractor should provide during periods of extensive
rainfall plastic sheeting to prevent improtected slopes fix)m becoming saturated and unstable.
When deemed appropriate by the geotechnical consultant or governing agencies the contractor
shall install checkdams, desilting basins, sand bags or other drainage control measures.
In relatively level areas and/or slope areas, where saturated soil and/or erosion gullies exist to
depths of greater than 1.0 foot; they should be overexcavated and replaced as compacted fill in
accordance with the applicable specifications. Where affected materials exist to depths of 1.0
foot or less below proposed finished grade, remedial grading by moisture conditioning in-place,
followed by thorough recompaction in accordance with the applicable grading guidelines herein
may be attempted. If the desired results are not achieved, aU affected materials should be
overexcavated and replaced as compacted fill in accordance with the slope repair
recommendations herein. If field conditions dictate, the geotechnical consultant may
recommend other slope repair procedures.
Section 6 - Excavations
6.1 Unsuitable Materials
Materials that are unsuitable should be excavated under observation and
recommendations of the geotechnical consultant. Unsuitable materials include, but may
not be limited to, dry, loose, soft, wet, organic compressible natural soils and fiinctured,
weathered, soft bedrock and nonengineered or otherwise deleterious fill materials.
Material identified by the geotechnical consultant as unsatisfactory due to its moisture
conditions should be overexcavated; moisture conditioned as needed, to a uniform at or
above optimum moisture condition before placement as compacted fill.
If during the course of grading adverse geotechnical conditions are exposed which were
not anticipated in the preliminary soil report as determined by the geotechnical consultant
additional exploration, analysis, and treatment of these problems may be recommended.
STANDARD SPECIFICATIONS OF GRADING
Page 3 of 26
Appendix D Page D-4
Standard Specifications for Grading
6.2 Cut Slopes
Unless otherwise recommended by the geotechnical consultant and approved by the
regulating agencies, permanent cut slopes should not be steeper than 2:1 (horizontal:
vertical).
The geotechnical consultant should obsawe cut slope excavation and if these excavations
expose loose cohesionless, significantly fi:actured or otherwise unsuitable material, the
materials should be overexcavated and replaced with a compacted stabilization fill. If
encountered specific cross section details should be obtained fix)m the Geotechnical
Consultant.
When extensive cut slopes are excavated or these cut slopes are made in the direction of
the prevailing drainage, a non-erodible diversion swale (brow ditdi) should be provided
at the top of the slope.
6.3 Pad Areas
All lot pad areas, including side yard terrace containing both cut and fill materials,
transitions, located less than 3 feet deep should be overexcavated to a depth of 3 feet and
replaced with a uniform compacted fill blanket of 3 feet Actual depth of overexcavation
may vary and should be delineated by the geotechnical consultant during grading,
especially where deep or drastic transitions are present.
For pad areas created above cut or natural slopes, positive drainage should be established
away fix)m the top-of-slope. This may be accomplished utilizing a beim drainage swale
and/or an appropriate pad gradient A gradient in soil areas away fix)m the top-of-slopes
of 2 percent or greater is recommended.
Section 7 - Compacted Fill
All fill materials should have fill quality, placement, conditioning and cortq)action as specified
below or as approved by the geotechnical consultant
7.1 Fill Material Ouahtv
Excavated on-site or import materials which are acceptable to the geotechnical consultant
may be irtilized as compacted fill, provided trash, vegetation and other deleterious
materials are ranoved prior to placement All import materials anticipated for use on-site
should be sampled tested and qjproved prior to and placement is in conformance with the
requirements outlined.
STANDARD SPECIFICATIONS OF GRADING
Page 4 of 26
Appendix D Page D-5
Standard Specifications for Grading
Rocks 12 inches in maximum and smaller may be utilized within compacted fill provided
sufficient fill material is placed and thoroughly compacted over and around all rock to
effectively fill rode voids. The amount of rock should not exceed 40 percent hy dry
weight passing the 3/4-inch sieve. The geotechnical consultant may vary those
requirements as field conditions dictate.
Where rocks greater than 12 inches but less than four feet of maximum dimension are
generated during grading, or otherwise desired to he placed within an engineered fill,
special handling in accordance with the recommendations below. Rocks greater than
four feet should he broken down or disposed off-site.
7.2 Placement of Fill
Prior to placement of fill material, the geotechnical consultant should observe and
approve the area to receive fill. After observation and approval, the exposed ground
surface should he scarified to a depth of 6 to 8 inches. The scarified material should he
conditioned (i.e. moisture added or air dried hy continued discing) to achieve a moisture
content at or sUghtly above optimum moisture conditions and compacted to a minimum
of 90 percent of the maximum density or as otherwise recommended in the soils report or
hy appropriate government agencies.
Compacted fill should then be placed in thin horizontal lifts not exceeding eight inches in
loose thickness prior to compaction. Each lift should be moisture conditioned as needed,
thoroughly blended to achieve a consistent moisture content at or shghtly above optimum
and thoroughly compacted hy mechanical methods to a minimum of 90 percent of
laboratory maximum dry density. Each lift should he treated in a like manner until the
desired finished grades are achieved.
The contractor should have suitable and sufficient mechanical compaction equipment and
watering apparatus on tiie job site to handle the amount of fill being placed in
consideration of moisture retention properties of the materials and weather conditions.
When placing fill ia horizontal lifts adjacent to areas sloping steeper than 5:1 (horizontal:
vertical), horizontal keys and vertical hendbes should he excavated into the adjacent slope
area. Keying and benching should he sufficient to provide at least six-foot wide benches
and a minimum of four feet of vertical bendi height within the firm natural ground, firm
bedrock or engineered compacted fill. No compacted fill should he placed in an area
after keying and benching until the geotechnical consultant has reviewed the area.
Material generated hy the benching operation should he moved sufficiently away finm
STANDARD SPECIFICATIONS OF GRADING
Page 5 of 26
Appendix D Page D-6
Standard Specifications for Grading
the bench area to allow for the recommended review of the horizontal bench prior to
placement of fill.
Within a single fill area where grading procedures dictate two or more separate fills,
tranporary slopes (felse slopes) may be created. When placing fill adjacent to a false
slope, benching should be conducted in the same manner as above described. At least a
3-foot vertical bench should be established within the firm core of adjacent approved
compacted fill prior to placement of additional fill. Benching should proceed in at least
3-foot vertical increments until the desired finished grades are achieved.
Prior to placement of additional compacted fill following an overnight or other grading
delay, the exposed surface or previously compacted fill should be processed by
scarification, moisture conditioning as needed to at or slightly above optimum moisture
content, thoroughly blended and reconq)acted to a minimum of 90 percent of laboratory
maximum dry density. Where unsuitable materials exist to depths of greater than one
foot, the unsuitable materials should be over-excavated.
Following a period of flooding, rainfall or overwatering by other means, no additional fill
should be placed until damage assessments have been made and remedial grading
performed as described herein.
Rocks 12 inch in maximum dimension and smaller may be utiUzed in the compacted fill
provided the fill is placed and thoroughly compacted over and around aU rock. No
oversize material should be used within 3 feet of finished pad grade and within 1 foot of
other compacted fill areas. Rocks 12 inches up to four feet maximum dimension should
be placed below the upper 10 feet of any fill and should not be closer than 15 feet to any
slope face. These recommendations could vary as locations of improvements dictate.
Where practical, ovCTsized material should not be placed below areas where structures or
deep utilities are proposed. Oversized material should be placed in windrows on a clean,
overexcavated or unyielding compacted fill or firm natural ground surface. Select native
or imported granular soil (S.E. 30 or higher) should be placed and thoroughly flooded
over and around all windrowed rock, such that voids are filled. Windrows of oversized
material should be staggered so those successive strata of oversized material are not in
the same vertical plane.
It may be possible to dispose of individual larger rock as field conditions dictate and as
recommended by the geotechnical consultant at the time of placement.
STANDARD SPECIFICATIONS OF GRADING
Page 6 of 26
Appendix D Page D-7
Standard Specifications for Grading
The contractor should assist the geotechnieal consultant and/or his representative by
digging test pits for removal determinations and/or for testing compacted fill. The
contractor should provide this work at no additional cost to the owner or contractor's
cHent
FiU should be tested by the geotechnieal consultant for compliance with the
recommended relative compaction and moisture conditions. Field density testing should
conform to ASTM Method of Test D 1556-00, D 2922-04. Tests should be conducted at
a minimum of approximately two vertical feet or approximately 1,000 to 2,000 cubic
yards of fill placed. Actual test intervals may vary as field conditions dictate. Fill found
not to be in conformance with the grading recommendations should be removed or
otherwise handled as recommended by the geotechnieal consultant
7.3 Fill Slopes
Unless otherwise recommended by the geotechnieal consultant and approved by the
regulating agencies, permanent fill slopes should not be steeper than 2:1 (horizontal:
vertical).
Except as specifically recommended in these grading guidelines compacted fill slopes
should be over-built two to five feet and cut back to grade, exposing the firm, compacted
fill inner core. The actual amount of overbuilding may vary as field conditions dictate. If
the desired results are not achieved, the existing slopes should be overexcavated and
reconstructed under the guidelines of the geotechnieal consultant. The degree of
overbuilding shall be inCTeased until the desired compacted slope surfiace condition is
achieved. Care should be taken by the contractor to provide thorough mechanical
compaction to the outer edge of the overbuilt slope surface.
At the discretion of the geotechnieal consultant, slope face compaction may be attempted
by conventional construction procedures including backroUing. The procedure must
create a firmly contacted material throughout the entire depth of the slope face to the
surface of the previously compacted firm fill intercore.
During grading operations, care should be taken to extend eompactive effort to the outer
edge of the slope. Each hft should extend horizontally to the desired finished slope
surface or more as needed to ultimately established desired grades. Grade during
construction should not be allowed to roll off at the edge of the slope. It may be helpful
to elevate slightly the outer edge of the slope. Slough resulting finm the placanent of
mdividual lifts should not be allowed to drift down over previous lifts. At intervals not
STANDARD SPECIFICATIONS OF GRADING
Page 7 of 26
Appendix D Page D-8
Standard Specifications for Grading
exceeding four feet in vertical slope height or the capabihty of available equipment,
whichever is less, fiU slopes should be thoroughly dozer trackxolled.
For pad areas above fill slopes, positive drainage should be established away fix)m the
top-of-slope. This may be accomplished using a berm and pad gradient of at least two
percent
Section 8 - Trench Backfill
Utility and/or other excavation of trench backfill should, unless otherwise recommended, be
compacted by mechanical means. Unless otherwise recommended, the degree of compaction
should be a minimum of 90 percent of the laboratory maximum density.
Within slab areas, but outside the influence of foundations, trenches up to one foot wide and two
feet deep may be backfilled with sand and consoUdated by jetting, flooding or by mechanical
means. If on-site materials are utilized, they should be wheel-rolled, tamped or otherwise
eompacted to a firm condition. For minor interior trenches, density testing may he deleted or
spot testing may be elected if deemed necessary, based on review of backfill operations during
construction.
If utihty contractors indicate that it is imdesirable to use compaction equipment in close
proximity to a biiried conduit, the contractor may elect the utilization of fight weight mechanical
compaction equipment and/or shading of the conduit with clean, granular material, whieh should
be thoroughly jetted in-place above the conduit, prior to initiating mechanical compaction
procedures. Other methods of utility trench compaction may also be appropriate, upon review of
the geotechnical consultant at the time of construction.
In cases where clean granular materials are proposed for use in lieu of native materials or where
flooding or jetting is proposed, die procedures should be considered subject to review by the
geotechnical consultant. Clean granular backfill and/or bedding are not recommended in slope
areas.
Section 9 - Drainage
Where deemed appropriate by the geotechnical consultant, canyon subdrain systems should be
installed in aceordance with CTE's recommendations during grading.
Typical subdrains for compacted fill buttresses, slope stabilization or sidehill masses, should he
installed in accordance with the speeifications.
STANDARD SPECIFICATIONS OF GRADING
Page 8 of 26
Appendix D Page D-9
Standard Specifications for Grading
Roofi pad and slope drainage should be directed away from slopes and areas of structures to
suitable disposal areas via non-erodible devices (i.e., gutters, downspouts, and concrete swales).
For drainage in extensively landscaped areas near structures, (i.e., within four feet) a minimum
of 5 percent gradient away fiwm the structure should be maintained. Pad drainage of at least 2
percent should be maintained over the remainder of the site.
Drainage patterns established at the time of fine grading should be maintained throughout the life
of the project. Property owners should be made aware that altering drainage patterns could be
detrimental to slope stability and foundation performance.
Section 10 - Slope Maintenance
10.1 - Landscape Plants
To enhance surficial slope stability, slope planting should be accomplished at the
completion of grading. Slope planting should consist of deep-rooting vegetation
requiring little watering. Plants native to the southern Califomia area and plants relative
to native plants are generally desirable. Plants native to other semi-arid and arid areas
may also be appropriate. A Landscape Architect should be the best party to consult
regarding actual types of plants and planting configuration.
10.2 - Irrigation
Irrigation pipes should be anchored to slope faces, not placed in trenches excavated into
slope faces.
Slope irrigation should be minimized. If automatic timing devices are utilized on
irrigation systems, provisions should be made for interrupting normal irrigation during
periods of rainfall.
10.3 - Repair
As a precautionary measure, plastic sheeting should be readily available, or kept on hand,
to protect aU slope areas from saturation by periods of heavy or prolonged rainfall. This
measure is strongly recommended, beginning with the period prior to landscape planting.
If slope feilures occur, the geotechnical consultant should be contacted for a field review
of site conditions and development of recommendations for evaluation and repair.
If slope failures occur as a result of exposure to period of heavy rainfall, the Mlure areas
and currently unaffected areas should be covered with plastic sheeting to protect against
additional saturation.
STANDARD SPECIFICATIONS OF GRADING
Page 9 of 26
Appendix D Page D-10
Standard Specifications for Grading
In the accompanying Standard Details, q)propriate repair procedures are illustrated for
superficial slope failures (i.e., occurring typically within the outer one foot to three feet of
a slope face).
STANDARD SPECIFICATIONS OF GRADING
Page 10 of 26
BENCHING FILL OVER NATURAL
SURFACE OF FIRM
EARTH MATERIAL
FILL SLOPE
5'MIN 4' TYPICAL
2'MIN 2%MIN
TYPICAL
15" MIN. (INCLINED 2% MIN. INTO SLOPE)
10'
BENCHING FILL OVER CUT
SURFACE OF FIRM
EARTH MATERIAL
FINISH FILL SLOPE
FINISH CUT
SLOPE
0^'
2% MIN 10'
4' TYPICAL
v:
"ttpicaP
15" MIN OR STABILITY EQUIVALENT PER SOIL
ENGINEERING (INCLINED 2% MIN. INTO SLOPE)
NOT TO SCALE
BENCHING FOR COMPACTED FILL DETAIL
STANDARD SPECIFICATIONS FOR GRADING
Page 11 of 26
TOE OF SLOPE SHOWN
ON GRADING PLAN
2% MIN
15" MINIMUM BASE KEY WIDTH
FILL
k
4"
10'TYPICAL BENCH
/ ««*■ r-v If-^ /
/ r
MINIMUM
DOWNSLOPE
KEY DEPTH
COMPETENT EARTH
MATERIAL
TYPICAL BENCH
HEIGHT
PROVIDE BACKDRAIN AS REQUIRED
PER RECOMMENDATIONS OF SOILS
ENGINEER DURING GRADING
WHERE NATURAL SLOPE GRADIENT IS 5:1 OR LESS,
BENCHING IS NOT NECESSARY. FILL IS NOT TO BE
PLACED ON COMPRESSIBLE OR UNSUITABLE MATERIAL.
NOT TO SCALE
FILL SLOPE ABOVE NATURAL GROUND DETAIL
STANDARD SPECIFICATIONS FOR GRADING
Page 12 of 26
w
H
>
Z
□>33
□
W
TJTO mw o
CD Z!
_L Ow >° S-h O
N) ZO) W
-nO
33
Q
□
Z
Q
REMOVE ALL TOPSOIL, COLLUVIUM,
AND CREEP MATERIAL FROM
TRANSmON
GUT/FILL CONTACT SHOWN
ON GRADING PLAN
CUT/FILL CONTACT SHOWN
ON "AS-BUILr
NATURAL
TOPOGRAPHY
CUT SLOPE*
FILL
4' TYPICAL
10' TYPICAL
15' MINIMUM ^
BEDROCK OR APPROVED
FOUNDATION MATERIAL
*NOTE: CUT SLOPE PORTION SHOULD BE
MADE PRIOR TO PLACEMENT OF FILL
NOT TO SCALE
FILL SLOPE ABOVE CUT SLOPE DETAIL
SURFACE OF
COMPETENT
MATERIAL
TYPICAL BENCHING
COMPACTED FILL
SEE DETAIL BELOW
DETAIL
FIEMOVE UNSUITABLE
MATERIAL
INCUNE TOWARD DRAIN
AT 2% GRADIENT MINIMUM
MINIMUM 9 FT" PER LINEAR FOOT
OF APPROVED FILTER MATERIAL
._CL
MINIMUM 4' DIAMETER APPROVED
PERFORATED PIPE (PERFORATIONS
DOWN)
6" FILTER MATERIAL BEDDING
" MINIMUM
CALTRANS CLASS 2 PEFIMEABLE MATERIAL
FILTER MATERIAL TO MEET FOLLOWING
SPECIFICATION OR APPROVED EQUAL:
SIEVE SIZE PERCENTAGE PASSING
r 100
%■90-100
%"40-100
NO. 4 25-40
NO. 8 18-33
NO. 30 5-15
NO. 50 0-7
NO. 200 0-3
APPROVED PIPE TO BE SCHEDULE 40
POLY-VINYL-CHLOFUDE (P.V.C.) OR
APPROVED EQUAL. MINIMUM CRUSH
STRENGTH 1000 psi
PIPE DIAMETER TO MEET THE
FOLLOWING CRITERIA, SUBJECT TO
FIELD FIEVIEW BASED ON ACTUAL
GEOTECHNICAL CONDITIONS
ENCOUNTEFIED DURING GRADING
LENGTH OF RUN
INITIAL 500"
500' TO 1500'
> 1500'
PIPE DIAMETER
4"
6"
8"
NOT TO SCALE
TYPICAL CANYON SUBDRAIN DETAIL
STANDARD SPECIFICATIONS FOR GRADING
Page 14 of 26
CANYON SUBDRAIN DETAILS
x-' ^
TYPICAL BENCHING
COMPACTED FILL
SURFACE OF
COMPETENT
MATERIAL
SEE DETAILS BELOW
REMOVE UNSUITABLE
MATERIAL
INCLINE TOWARD DRAIN
AT 2% GRADIENT MINIMUM
TRENCH DETAILS
6" MINIMUM OVERLAP
OPTIONAL V-DITCH DETAIL
MIRAFI 140N FABRIC
OR APPROVED EQUAL
6" M N MUM OVERLAP
24"
MINIMUM
MINIMUM
MINIMUM 9 FP PER LINEAR FOOT
OF APPROVED DRAIN MATERIAL
60° TO 90°
MINIMUM 9 FT" PER LINEAR FOOT
OF APPROVED DRAIN MATERIAL
MIRAFI 140N FABRIC
OR APPROVED EQUAL
APPROVED PIPE TO BE
SCHEDULE 40 POLY-
VINYLCHLORIDE (P.V.C.)
OR APPROVED EQUAL.
MINIMUM CRUSH STFLENGTH
1000 PSI.
DRAIN MATERIAL TO MEET FOLLOWING
SPECIFICATION OR APPROVED EQUAL
SIEVE SIZE PERCENTAGE PASSING
PIPE DIAMETER TO MEET THE
FOLLOWING CRITERIA, SUBJECT TO
FIELD REVIEW BASED ON ACTUAL
GEOTECHNICAL CONDITIONS
ENCOUNTERED DURING GRADING
NOT TO SCALE
1X2"88-100
LENGTH OF RUN PIPE DIAMETER
1"5-40
INITIAL 500'4"
%"0-17
500' TO 1500'6"
%■0-7 > 1500'8"
NO. 200 0-3
GEOFABRIC SUBDRAIN
STANDARD SPECIFICATIONS FOR GRADING
Page 15 of 26
FRONT VIEW
CONCRETE
CUT-OFF WALL"
SUBDRAIN PIPE
24" MIn.
6" MIn.
6" MIn.
6"Min.
SIDE VIEW
CONCRETE
CUT-OFF WALL
SCHLD SUBDRAIN PIPE
TBOor
12" MIn.
-T
k ' k '
6" MIn.
6" MIn.
PERFORATED SUBDRAIN PIPE'
ft, ' * ,
SOW
TSOW
NOT TO SCALE
RECOMMENDED SUBDRAIN GUT-OFF WALL
STANDARD SPECIFICATIONS FOR GRADING
Page 16 of 26
FRONT VIEW
SUBDRAIN OUTLET
PIPE (MINIMUM 4" DIAMETER)
24" MIn.
24" MIn.
SIDE VIEW
CONCRETE
HEADWALL
ALL BACKFILL SHOULD BE COMPACTED
IN CONFORMANCE WITH PROJECT
SPECIFICATIONS. COMPACTION EFFORT
SHOULD NOT DAMAGE STRUCTURE
-24" MIn.
NOTE: HEADWALL SHOULD OUTLET AT TOE OF SLOPE
OR INTO CONTROLLED SURFACE DRAINAGE DEVICE
ALL DISCHARGE SHOULD BE CONTROLLED
THIS DETAIL IS A MINIMUM DESIGN AND MAY BE
MODIFIED DEPENDING UPON ENCOUNTERED
CONDITIONS AND LOCAL REQUIREMENTS
NOT TO SCALE
TYPICAL SUBDRAIN OUTLET HEADWALL DETAIL
STANDARD SPECIFICATIONS FOR GRADING
Page 17 of 26
15" MINIMUM
4" DIAMETER PERFORATED
PIPE BACKDRAIN
4" DIAMETER NON-PERFORATED
PIPE LATERAL DRAIN
SLOPE PER PLAN
FILTER MATERIAL
2% MIN
-BENCHING
AN ADDITIONAL BACKDRAIN
AT MID-SLOPE WILL BE REQUIRED FOR
SLOPE IN EXCESS OF 40 FEET HIGH.
KEY-DIMENSION PER SOILS ENGINEER
(GENERALLY 1/2 SLOPE HEIGHT, 15' MINIMUM)
DIMENSIONS ARE MINIMUM RECOMMENDED
NOT TO SCALE
TYPICAL SLOPE STABILIZATION FILL DETAIL
STANDARD SPECIFICATIONS FOR GRADING
Page 18 of 26
15'MINIMUM
4" DIAMETER PERFORATED
PIPE BACKDRAIN
4" DIAMETER NON-PERFORATED
PIPE LATERAL DRAIN
SLOPE PER PLAN
FILTER MATERIAL BENCHING
2% MIN
ADDITIONAL BACKDRAIN AT
MID-SLOPE WILL BE REQUIRED
FOR SLOPE IN EXCESS OF 40
FEET HIGH.
KEY-DIMENSION PER SOILS ENGINEER
DIMENSIONS ARE MINIMUM RECOMMENDED
NOT TO SCALE
TYPICAL BUTTRESS FILL DETAIL
STANDARD SPECIFICATIONS FOR GRADING
Page 19 of 26
FINAL LIMIT OF
EXCAVATION
DAYLIGHT
LINE
20' MAXIMUM
OVEREXCAVATE
FINISH PAD
OVEREXCAVATE 3'
AND REPLACE WITH
COMPACTED FILL
COMPETENT BEDROCK
2% MIN
2' MINIMU
OVERBURDEN
(CREEP-PRONE)
TYPICAL BENCHING
LOCATION OF BACKDRAIN AND
OUTLETS PER SOILS ENGINEER
AND/OR ENGINEERING GEOLOGIST
DURING GRADING. MINIMUM 2%
FLOW GRADIENT TO DISCHARGE
LOCATION.
EQUIPMENT WIDTH (MINIMUM 15")
NOT TO SCALE
DAYLIGHT SHEAR KEY DETAIL
STANDARD SPECIFICATIONS FOR GRADING
Page 20 of 26
NATURAL GROUND
PROPOSED GRADING
1.5.
1.5
COMPACTED FILL
BASE WIDTH "W" DETERMINED
BY SOILS ENGINEER
PROVIDE BACKDRAIN, PER
BACKDRAIN DETAIL. AN
ADDITIONAL BACKDRAIN
AT MID-SLOPE WILL BE
REQUIRED FOR BACK
SLOPES IN EXCESS OF
40 FEET HIGH. LOCATIONS
OF BACKDRAINS AND OUTLETS
PER SOILS ENGINEER AND/OR
ENGINEERING GEOLOGIST
DURING GRADING. MINIMUM 2%
FLOW GRADIENT TO DISCHARGE
LOCATION.
NOT TO SCALE
TYPICAL SHEAR KEY DETAIL
STANDARD SPECIFICATIONS FOR GRADING
Page 21 of 26
FINISH SURFACE SLOPE
3 FT' MINIMUM PER LINEAR FOOT
APPROVED FILTER ROCK*
COMPACTED FILL
GRAD ENT
CONCRETE COLLAR
PLACED NEAT
2.0% MINIMUM
A-i
4" MINIMUM DIAMETER
SOLID OUTLET PIPE
SPACED PER SOIL
ENGINEER REQUIREMENTS
DURING GRADING TYPICAL
BENCHING
4" MINIMUM APPROVED
PERFORATED PIPE**
(PERFORATIONS DOWN)
MINIMUM 2% GRADIENT
TO OUTLET
BENCH INCUNED
TOWARD DRAIN
DETAIL A-A
TEMPORARY FILL LEVEL
MINIMUM
12" COVER
DOMPACTEC
BACKFILL
12"
MINIMUM ^
MINIMUM 4" DIAMETER APPROVED
SOLID OUTLET PIPE
**APPROVED PIPE TYPE:
SCHEDULE 40 POLYVINYL CHLORIDE
(P.V.C.) OR APPROVED EQUAL.
MINIMUM CRUSH STRENGTH 1000 PSI
*FILTER ROCK TO MEET FOLLOWING
SPECIFICATIONS OR APPROVED EQUAL:
SIEVE SIZE
1"
%■
%'
NO. 4
NO. 30
NO. 50
NO. 200
PERCENTAGE PASSING
100
90-100
40-100
2&40
5-15
0-7
0-3
NOT TO SCALE
TYPICAL BACKDRAIN DETAIL
STANDARD SPECIFIGATIONS FOR GRADING
Page 22 of 26
FINISH SURFACE SLOPE
MINIMUM 3 FT* PER UNEAR FOOT
OPEN GRADED AGGREGATE*
TAPE AND SEAL AT COVER
CONCRETE COLLAR
PLACED NEAT
COMPACTED FILL
2.0% MINIMUM GRADIENT
A-
MINIMUM 4" DIAMETER
SOLID OUTLET PIPE
SPACED PER SOIL
ENGINEER REQUIREMENTS
TYPICAL
BENCHING
MIRAFI 140N FABRIC OR
APPROVED EQUAL
MINIMUM APPROVED
PERFORATED PIPE
(PERFORATIONS DOWN)
MINIMUM 2% GRADIENT
TO OUTLET
BENCH INCLINED
TOWARD DRAIN
DETAIL A-A
TEMPORARY FILL LEVEL
MINIMUM
12" COVER
*NOTE: AGGREGATE TO MEET FOLLOWING
SPECIFICATIONS OR APPROVED EQUAL
SIEVE SIZE
1*
%•
%'
NO. 200
PERCENTAGE PASSING
100
5-40
0-17
0-7
0-3
lOMPACTEP
BACKFILL
id
12"
MINIMUM '
MINIMUM 4" DIAMETER APPROVED
SOLID OUTLET PIPE
NOT TO SCALE
BACKDRAIN DETAIL (GEOFRABIC)
STANDARD SPECIFIGATIONS FOR GRADING
Page 23 of 26
SOIL SHALL BE PUSHED OVER
ROCKS AND FLOODED INTO
VOIDS. COMPACT AROUND
AND OVER EACH WINDROW.
CLEAR ZONE
^ EQUIPMENT WIDTH ^ ^
STACK BOULDERS END TO END.
DO NOT PILE UPON EACH OTHER.
FILL SLOPE
10' MIN
STAGGER
ROWS
NOT TO SCALE
ROCK DISPOSAL DETAIL
STANDARD SPECIFICATIONS FOR GRADING
Page 24 of 26
FINISHED GRADE
SLOPE FACE
A
BUILDING
NO OVERSIZE, AREA FOR
FOUNDATION. UTILITIES
AND SWIMMING POOLSn
-^5 ■o
WINDROW J
5' MINIMUM OR BELOW
DEPTH OF DEEPEST
UTILITY TRENCH
(WHICHEVER GREATER)
TYPICAL WINDROW DETAIL (EDGE VIEW)
GRANULAR SOIL FLOODED
TO FILL VOIDS
HORIZONTALLY PLACED
COMPACTION FILL
PROFILE VIEW
NOT TO SCALE
ROCK DISPOSAL DETAIL
STANDARD SPECIFIGATIONS FOR GRADING
Page 25 of 26
GENERAL GRADING RECOMMENDATIONS
CUT LOT
5'
TOPSOIL, COLLUVIUM AND
WEATHERED BEDROCK
UNWEATHERED BEDROCK
•ORIGINAL
GROUND
5' MIN
3' MIN
OVEREXCAVATE
AND REGRADE
CUT/FILL LOT (TRANSITION)
COMPACTED FILL
TOPSOIL, COLLUVIUM
-AND WEATHERED
BEDROCK ^
UNWEATHERED BEDROCK
ORIGINAL
.^GROUND
M N
3' MIN
OVEREXCAVATE
AND REGRADE
NOT TO SCALE
TRANSITION LOT DETAIL
STANDARD SPECIFICATIONS FOR GRADING
Page 26 of 26
APPENDIX E
WORKSHEETS D.5-1 and 1-8
Appendix D: Approved Infiltration Rate Assessment Methods
Worksheet D.5-1: Factor of Safety and Design Infiltration Rate Worksheet
Factor of Safety and Design Infiltration Rate Worksheet Worksheet D.5-1
Factor Category Factor Description Assigned
Weight (w)
Factor
Value (v)
Product (p)
p = WX V
Soil assessment methods 0.25 1 0.25
Predominant soil texture 0.25 2 0.50
A Suitability Site soil variability 0.25 2 0.50
Assessment Depth to groundwater / impervious
layer 0.25 1 0.25
Suitability Assessment Safety Factor, Sa = 2)p 1.5
Level of pretreatment/ expected
sediment loads 0.5 2 1.0
B Design Redundancy/resiliency 0.25 2 0.50
Compaction during construction 0.25 2 0.50
Design Safety Factor, Sb = £p 2.0
Combined Safety Factor, Sto«a]= Sa x Sb 3.5
Observed Infiltration Rate, inch/hr, Kobserved
(corrected for test-specific bias)0.050
Design Infiltration Rate, in/hr, Kdesign = Kobswcd / Stotai 0.014
Supporting Data
Briefly describe infiltration test and provide reference to test forms:
Infiltration rates were determined by performing percolation tests in accordance with the DEH method.
All of the percolation tests were performed in native material and two of the tests did not percolate.
D-17
Worksheet 1-8 : Categorization of Infiltration Feasibility Condition
Categorization of Infiltration Feasibility Condition Worksheet 1-8
Part 1 - Full Infiltration Feasibility Screening Criteria
Would infiltration of the full design volume be feasible from a physical perspective widiout 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.
X
Provide basis: The NRCS soils across the site are all Type D soils with high surface runoff. The site soils are
consistent with the NRCS mapped soil types based on site explorations and percolation testing.
Two soil types were present in the area of the proposed development. Residual Soil and
Metavolcanic/ Metasedimentary rock.
Three percolation tests were completed, with two tests performed within the native soils and one
performed in the Previously Placed Fill. The calculated infiltration rates (with an applied factor of
safety of 3.5) ranged from not infiltrating to 0.014 inch per hour.
Summarize findings of studies; provide reference to studies, calculations, maps, data sources, etc. Provide
narrative discussion of study/data source apphcability.
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: Not Applicable.
Summarize findings of studies; provide reference to studies, calculations, maps, data sources, etc. Provide
narrative discussion of study/data source apphcability.
C-11
Worksheet 1-8 Page 2 of 4
Criteria Screening Question Yes No
3
Can infiltration greater than 0.5 inches per hour be allowed without increasing
risk of groundwater contamination (shallow water table, storm 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: Not Applicable.
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; Not Applicable.
Summarize findings of studies; provide reference to studies, calculations, maps, data sources
narrative discussion of study/data source applicability.
, etc. Provide
Parti
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 "fuU 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 Cit)' Engineer to substantiate findings.
C-12
Worksheet 1-8 Page 3 of 4
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 Screening Question Yes No
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
Appendix D.
X
Provide basis: to the native soils not percolating it is unlikely that any appreciable volume of water will
infiltrate.
Summarize findings of studies; provide reference to studies, calculations, maps, data sources, etc. Provide
narrative discussion of study/data source applicability and why it was not feasible to mitigate low
infiltration rates.
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 Question shall be based on a comprehensive evaluation of the
factors presented in Appendix C.2.
Provide basis: Due to the minimal pemieability of the geologic units encountered at the site, surface water would
likely migrate laterally or moimd locally. This could result in the water migrating into utility
trench backfill or saturating down gradient foundations or other improvement areas.
Summarize findings of studies; provide reference to studies, calculations, maps, data sources, etc. Provide
narrative discussion of smdy/data source applicability and why it was not feasible to mitigate low
infiltration rates.
C-13
Worksheet 1-8 Page 4 of 4
Criteria Screening Question Yes No
Can Infiltration in any appreciable quantity 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
Appendix C.3.
X
Provide basis:According to Geotracker, the nearest known "Open" LUST cleanup site is over 4,000 feet away
from the site.
Summarize findings of studies; provide reference to studies, calculations, maps, data sources, etc. Provide
narrative discussion of study/data source applicability and why it was not feasible to mitigate low
infiltration rates.
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.
X
Provide basis: San Marcos Creek is the nearest down gradient drainage with surface water and is over 900 feet
from the site. Due to the significant distance to the drainage it is unlikely to be impacted by
infiltrating site water.
Summarize findings of studies; provide reference to studies, calculations, maps, data sources, etc. Provide
narrative discussion of study/data source applicability and why it was not feasible to mitigate low
infiltration rates.
Part 2
Result*
If all answers from row 1-4 are yes then partial infiltration design is potentially feasible.
The feasibilit}' 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 City Engineer to substantiate findings
C-14