HomeMy WebLinkAboutTract Map 30667-1 As Graded Rough Gradinga
0
a
0
Q AS-GRADED REPORT OF ROUGH GRADING
FOR HARVESTON TRACT 30667-1
O CITY OF TEMECULA, CALIFORNIA
a
Q Prepared For:
0 Lennar Communities
391. N. Main Street, Suite 301
Corona,. California 92880
0
September 24, 2003
Q Project No. 110231-024
0 ~
~ Leighton and Associates, Inc.
A LEIGHTON GROUP COMPANY ('
0
D
0
0
O
a
a
0
~~
Leighton and Associates, Inc.
A LEIGHTON GROUP COMPANY
September 24, 2003
To: Lennar Communities
391 N. Main Street, Suite 301
Corona, Califonua 92880
Attention: Mr. Bill Storm
Project No. 110231-024
Subject: As-Graded Report of Rough Grading for Harveston, Tract 30667-1, City of
Temecula, California.
In accordance with your request and authorization, Leighton and Associates, hic. (Leighton) has been
providing geotechnical observation and testing services during rough grading operations of Tract
30667-1, located in the City of Temecula, Califomia (See Figure 1). The accompanying as-graded
report summarizes our observations, field and laboratory test results and the geotechnical conditions
encountered during the rough grading of lots 1 through 36 of Tract 30667-1 within the Harveston
Community.
Lf you have any questions regarding this report, please do not hesitate to contact this office, we
appreciate this opportunity to be of service.
Respectfully submitted,
LEIGHTON AND
Robert F. Riha, CEG 19
Vice President/Principal
RFR/CER/mm
t r oz~ t mar^I><v>I~-aa,~ r,~s ~ac~-~
Cameron Roberson, RCE
Project Engineer
Distn'bution: (6) Addressee
(2) Harveston Jobsite; Attention: Mr. Bob Hall
0
Z-
41715 Enterprise Cirde N., Suite 103 ^ Temecula, CA 92590-5661
909.296.0530 ^ Fax 909.296.0534 ^ www.leightongeo.com
0
a
0
O
a
0
on
1.0 INTRODUCTION ,,,,,,,
2.0 SUMMARY OF ROUGH-GRADING OPERATIONS,,,,,,,,,,,,,,,,,,,,,
110231-024
September 24, 2003
P~
..........................1
..................2
2.1 Site Preparation and Removals ........................ ............................................................2
2.2 Reld Density Testin9 ....................................... ............................................................2
2.3 Laboratory Testlng .......................................... ............................................................2
2.4 RII Placement ................................................. ............................................................3
2.5 Canyon Subdreins ........................................... ...........................................................:3
3.0 ENGINEERING GEOLOGIC SUMMARY ...............................................................................: 4
3.1 As-Graded Geologic Conditions ....................................................................................4
3.2 Geologic Units ............................................................................................................4
3.2.1 Ariifidal RII (~ .................................................................................................. 4
3.2.2 Artifical RII Leighton (Afl) ................................................................................... 4
3.3 Geologic Structure and Faultin9 ..................................................................................:4
3.4 Landslides and Surficial Failures ...................................................................................5
3.5 Groundwater ..............................................................................................................5
3.6 Expansion Testing of Rnish Grade Soils ........................................................................5
4.0 CONCLUSIONS .................................................................................................................6
4.1 General .................................................................................................... 6
..................
4.2 Summary of Condusions .............................................................................................6
5.0 RECOMMENDATIONS ........................................................................................................8
5.1 Earthwork ..................................................................................................................8
5.1.1 Excavations .......................................................................................................8
5.1.2 Bacldill, RII Placement and Compaction,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,8
5.2 Foundation and Structure Design Considerations ,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,8
5.3 Foundation Setback from Slopes ................................................................................10
5.4 Structure Seismic Design Parameters .........................................................................10
5.5 Corrosion .................................................................................................................11
5.6 Lateral Earth Pressures and Retaining Wall Design Considerations 11
...............................
5.7 Concrete Ratwork ....................................................................................................12
5.8 Control of Surface Water and Drainage Control ...........................................................13
Q 5.9 Graded Slopes ..........................................................................................................13
5.l0Irrigation, Landscaping and Lot Maintenance .............................................................13
5.11 Post-Grading Geotechnical Review ............................................................................14
-t-
Leighton
D
io
is
D
Table of Contents (oo~)
5.11.1 Construction Review .......................................................................................14
5.11.2 Plans and Specificatlons ..................................................................................14
6.0 LIMITATIONS ......................
110231-024
September 24, 2003
...............15
Accompany~r,a Fgures. Tables. Plates and Appendices
0
Figure 1-Site Location Map
Figure 2 -Retaining Wall Drainage Detail
Tables
Table 1 - Lot by Lot Summary of As-graded Geotechnical
Conditions and Recommendations
Table 2 - Minimum Conventional Foundatlon Design Reoommendations
Table 3 - Minimum Post-Tensioned Foundatlon Design Recommendations
Table 4 - Lateral Earth Pressures
Rear of Text
Rear of Text
Rear of Text
Rear of Text
Rear of Text
Rear of Text
Plate
Plate 1 - As-Graded Geotechnical Map
Appendices
Appendix A -References
Append'a B - Summary of Feld Density Tests
Appendix C -Laboratory Testing Procedures and Test Results
Appendix D -Lot Maintenance Guidelines for Owners
D
D
0
In Pocket
Leighton
110231-024
September 24, 2003
1.0
D
D
0
In accordance with your request and authorization, Leighton and Associates, Tnc. (Leighton) has
performed geotechnical observation and testing services during the latest rough-grading operations
of Lots 1 through 36 of Tract 30667-1 within the Harveston Community. The subject property had
been previously "sheet" mass graded under the observation and testing of Leighton (Leighton,
2003).
This as-graded report summarizes our geotechnical observations, field and laboratory test results
and the geotechnical conditions encountered during the recent rough grading of the subject lots.
In addition, this report provides conclusions and recommendations for the proposed development
of the subject lots.
The reference 40-scale grading plans for Tract 30667-1 (RBF, 2003) were annotated and utilized as
a base map (Plate 1) to plot geotechnical conditions and the approximate locations of the field
density tests taken during rough-grading operations.
~,
-1- Leighton
0
D
O
a
0
0
110231-024
September 24, 2003
2.0 SUMMARY OF ROUGH-GRADING OPERATIONS
Tract 30667-1 was initially sheet graded as Lot 14 within Tract 29639-1 under the observation and
testing of Leighton (Leighton, 2003). Rough grading to the approved design configuration (RBF,
2003) was conducted by ACI, Inc. in July through August of 2003, under the geotechnical observation
and testing services of Leighton. Leighton field technician(s) and geologist were onsite on a full-time
and as-needed basis, respectively, during grading operations. Grading involved the complete removal
of desiccated fill, erosion rills and surface erosion sediments to competent previously-placed
compacted fill (Leighton, 2003) and the placement of compacted artificial fill to depths of
approximately twelve feet to create the design residential lots and associated roadways.
2.1 Sibs Prenaratlon and Removals
Prior to grading, deleterious materials were removed from the areas of proposed development
and disposed of offsite. Grading of the subject site was accomplished by removal of unsuitable
surficial material. The removals were completed until competent previously-placed
compacted fill (Leighton, 2003) was encountered in accordance with the recommendations of
the project geotechnical reports (Appendix A) and the geotechnical recommendations made
during grading operations.
2.2 Field Density Tesdna
Field density testing was performed using the nucleaz gauge method (ASTM Test Methods
D D2922 and D301'n. Tested areas appear to meet the minimum required 90 percent relative
compaction with optimum moisture content or above. Areas that tested less than the required 90
D
D
a
S~
percent relative compaction, were reworked, moisture conditioned as necessary and compacted
until the minimum 90 percent was obtained The results and approximate locations of the field
density tests are summarized in Appendix B. The approximate locations of the field density tests
are depicted on the enclosed As-Graded Geotechnical Map (Plate 1).
2.3 Laboratory Testing
Laboratory compaction characteristics (maximum dry density and optimum moisture),
expansion index, Atterberg limits, and soluble sulfate tests of representative onsite soils were
performed during the course ofrough-grading and are presented in Appendix C. The lot by lot
laboratory test results are presented in Table 1. A description of the laboratory test procedures
is presented in Appendix C.
-2 Leighton
0
a
O
D
0
D
2.4 Fill Placement
110231-024
September 24, 2003
Fill materials consisting of the soil types listed in Appendix C were placed in thin lifts of
approximately eight inches, processed and moisttre conditioned to near optimum moisture
content or above, and compacted in place to a minimum of 90 percent of the laboratory derived
maximum density. Fill placement and compaction was accomplished with the use of heavy
earthwork equipment.
2.5 Canvon Sulxlrains
The existing canyon subdrain constructed during rough-grading of Tract 29639-1 (Leighton,
2003) should be outletted to the planned permanent storm drain system that outlets into the
Santa Gen7udis Creek during the stone drain construction of Tract 30667-2. The approximate
location of the subdrain is presented on the As-Graded Geotechnical Map (Plate 1). Canyon
subdrains, as constructed, were surveyed by 1tBF.
-3-
Leighton
0
0
D
D
D
D
a
110231-024
September 24, 2003
3.0 ENGINEERING GEOLOGIC SUMMARY
3.1 As-Graded Geologic Conditlons
The as-graded conditions encountered during grading of the subject lots was essentially as
anticipated. A summary of the geologic conditions, including geologic units, geologic structure
and faulting is presented below.
3.2Geologic Units
The geologic units observed during grading of the subject lots consisted of Artificial Fill (Af),
and previously-placed compacted fill (Afl) which are discussed below:
3.2.1 Artlfidal Fill fAfl -Locally derived artificial fill soils generally consisted of olive gray to
olive brown silty sand to locally slightly clayey silty sand Artificial fill soils were placed
under the observation and field density testing by Leighton representatives during this
phase of grading. After moisture conditioning and thorough mixing, the artificial fill soils
were placed in relatively thin (8-10 inches) lifts and compacted utilizing heavy duty
construction equipment.
3.2.2 Artificial FII Leighton (~ -The artificial fill encountered generally consisted of
brown to dark brown, moist, medium dense to dense silty sand As encountered during
grading, the ariificial fill was generally moderately dense near the surface, becoming dense
with depth. The weathered artificial fill materials were scarified to a depth of 6 inches,
moistured conditioned and thoroughly mixed and re-used as compacted fill.
3.3 Geologic Structure and Faulting
Based on our geologic observations during site grading, the Pauba Formation is massive with
localized bedding, which is generally flat lying. No faulting or indications of faulting were
anticipated or observed within or immediately adjacent to the subject tract. No faulting or
indications of active faulting was anticipated nor observed within the subject lots during rough-
grading operations. The nearest "zoned" active fault is the Temecula Segment of the Elsinore
Fault Zone located approximately 1.1 miles (1.8 km) to the southwest.
- 4 Leighton
D
0
0
O
0
0
110231-024
September 24, 2003
3.4 Landslides and Surfldal Failures
Based on our review of the project geotechnical reports (Appendix A) and our geologic
observations during the course of grading operations, there were no indications of landslides or
other significant surficial failures within the subject tract. It should be noted that unplanted or
..unprotected slopes are subject to erosion and subsequent surficial instability.
3.5 Groundwater
Groundwater was not encountered during recent or previous (Leighton, 2003) rough grading.
Canyon subdrains were constructed in general accordance with the project geotechnical
reports (Appendix A) and our field recommendations during the previous grading (Leighton,
2003). However, unforeseen conditions may occur after the completion of grading and
establishment of site irrigation and landscaping. Perched groundwater may accumulate at layers
of differing permeability or at bedrock/fill contacts. If these conditions-should occur, methods
should be taken to mitigate any resulting seepage. Presently the majority of the subject site
drains towards the south and any surface runoff will tend to collect at low points until such. time
that the proposed desig- drainage facilities are constructed. If water is allowed to pond in these
areas for any length of time the subgrade in these areas may become saturated and additional
grading recommendations maybe required to mitigate this condition. We recommend that the
project erosion control program be designed and implemented as soon as possible to limit the
potential of erosion damage or adverse effects to compacted-fill.
3.6 Emansion Testing of Finish Grade Soils
Expansion index testing was performed on representative near finish grade soils of the subject
lots. The test results indicate the on lot near-finish grade soils have a medium expansion potential
in accordance with Table 18-I-B of the 1997 UBC. Test results of samples taken during the
course of grading indicate that very low to very high expansive soils exist on site at various depths
and locations. Test procedures and results are presented in Appendix C. A lot by lot summary of
the as-graded conditions for the subject lots is presented in Table 1.
- s Leighton
.110231-024
September 24, 2003
O 4.0 CONCLUSIONS
4.1Oeneral
Q The grading of the subject lots was performed in general accordance with the project geotechnical
reports and geotechnical recommendations made during the course of rough grading. It is our
professional opinion that the subject lots are suitable for their intended residential use provided
the recommendations included herein and in the project geotechnical reports are incorporated into
the design and conshuction of the residential structures and associated improvements.
4.2 Summarp of Condusfons
• Geotechnical conditions encountered during rough grading of the subject site were generally
as anticipated.
• Excavations were made to dense previously-placed compacted fill (Afl) material during the
grading for the subject lots.
• Fill slopes within the subject tract range up to approximately 8 feet in height. It is our
opinion that the compacted fill slopes on the subject lot are surficially and grossly stable
(under normal irrigation/precipitation patterns) provided the recommendations in the project
geotechnical reports and memorandums are incorporated into the post-grading, constnution
and post-construction phases of site development. Slopes are inherently subject to erosion.
As such, measures should be taken as soon as possible to reduce erosion for both short term
and long term slope integrity.
• Laboratory testing of soils encountered during the course of grading indicates site soils to
possess a very low to very high expansion potential. Some expansive soil related distress to
flatwork should be anticipated. It is our opinion that the near surface soils influencing the
design of foundation and slabs of the subject tract should be considered to be medium
expansive (per UBC).
Laboratory testing of near finish grade soils within building footprints indicates materials
which posses a medium expansion potential and have a negligible concentration of soluble
sulfate. Laboratory test results are contained herein Table 1 and Appendix C.
0 • Testing for minimum resistivity, chloride concentrates, and pH was not conducted during
the course of rough grading. A licensed contusion engineer should be contacted in regard to
determining the potential for corrosion if corrosion sensitive buried improvements are to be
installed.
• The potential for ground-surface rupture on the site due to a seismic event is considered to
a be low; however, as in most of southern California, strong ground shaking should be
anticipated during the life of the structures. The standard design of structures to meet the
seismic design requirements of the Uniform Building Code (iJBC), Seismic Zone 4 will be
Q required.
-6-
Leighton
a 110231-024
September 24, 2003
O • Where tested, fill material placed during grading of the subject tract was placed at a
a minimum of 90 percent relative compaction at or above the optimum moisture content.
Field testing of compaction was performed by the nuclear gauge method (ASTM Test
Methods D2922 and D3017).
a . Foundations should be designed and constructed in accordance with Leighton's minimum
recommendations herein, the requirements of the City of Temecula and the applicable
sections of the 1997 UBC.
a
O
O
a
0
a
0
a
a
a
• Due to the relatively dense nature of the bedrock materials that underlie the subject site, the
competency of compacted fills, as well as the lack of pemument shallow groundwater, the
potential for liquefaction on the site is considered very low.
• The front yard and driveway areas were intentionally left below design elevations
(approximately 2 to 3.5 feet below pad grade) to accommodate future lot excavation spoils.
Filling of these areas should be performed in accordance with the recommendations herein
for earthwork (section 5.1.2).
_~_
Leighton
~o
5.1 ~
110231-024
September 24, 2003
5.0 BECOMMENDATiONS
Q We anticipate that future earthwork at the site will consist of precise grading of the building
pads, foundation installation, trench excavation and backfill, retaining wall backfill,
preparation of street subgrade, and placement of aggregate base and asphalt wncrete
Q pavement. We rewmmend that any additional earthwork on the site be performed in
accordance with the following recommendations and the City of Temecula grading
requirements.
O 5.1.1 Excavations -- Temporary excavations with vertical sides, such as utility trenches,
should remain stable to depths of 4 feet or less for the period required to construct the
utility. However, in accordance with OSHA requirements, excavations greater than 4
feet in depth should be shored, or laid-back to inclinations of 1:1 (horizontal to
0 vertical), if workers are to enter such excavations. Leighton does not consult in the
area of safety engineering. The contractor is responsible for the safety of all
excavations.
a 5.1.2 Backfil~, Flll Placement and Compaction -All backfill or fill soils should be
brought to optimum moisture conditions and compacted in uniform lifts to at least 90
0 percent relative compaction based on the laboratory maximum dry density (ASTM
Test Method D1557). The optimum lift thickness required to produce uniform
compaction will depend on the type, size and condition of compaction equipment
used. In general, the onsite soils should be placed in lifts not exceeding 8 inches in
compacted thickness and placed on dense existing compacted fill or other earth
material approved by the geotechnical consultant.
5.2 Foundation and Structure Design Considerations
It is Leighton's understanding that single-family structures founded on post-tensioned or
conventional foundation systems are proposed. The proposed foundations and slabs should
be designed in accordance with the structural consultants' design, the minimum geotechnical
recommendations presented herein (text, Table 1 through 3), the City of Temecula
requirements and the 1997 UBC. In utilizing the minimum geotechnical foundation
O recommendations, the structural consultant should design the foundation system to acceptable
deflection criteria as determined by the structural engineer and architect.
0
-8-
Leighton
0
O
O
a
110231-024
Sepbemt~er 24, 2003
Foundation footings may be designed with the following parameters:
Allowable Bearing Capacity: 2000 psf at a minimum depth of embedment of 12
inches, plus an additional 250 psf per 6 inches of
additional embedment to a maximum of 2500 psf.
(per 199'1 UBC, capacities may be increased by 1/3 for
short-term loading conditions, i.e., wind, seismic)
Sliding CoefTicient: 0.35
Settlement Potential
Lots 1 - 36
Total: 1 inch
I}ifferential: l Inch in 40 Feet
The footing width, depth, reinforcement, slab reinforcement, and the slab-on-grade thickness
should be designed by the structural consultant based on recommendations and soil
characteristics indicated herein (Tables 1 through 3), and the most recently adopted edition of
the UBC. The under-slab moisture barrier should consist of 2 inches of sand (S.E. > 30) over
10 mil visqueen over an additional 2 inches of sand (a total of 4 inches of sand). The
recommended vapor barrier should be sealed at all penetrations and laps.. Moisture vapor
transmission may be additionally reduced by use of concrete additives. Moisture vapor
barriers may retard but not eliminate moisture vapor movement from the underlying soils up
through the slabs. A slipshcet or equivalent should be utilized above the concrete slab if
crack-sensitive floor coverings (such as ceramic tiles, etc.) are to be placed directly on the
concrete slab.
p Our experience indicates that use of reinforcement in slabs and foundations will generally
reduce the potential for drying and shrinkage cracking.. However, some cracking should be
expected as the wncrete cures. Minor cracking is considered normal; however, it is often
aggravated by a high water/cement ratio, high concrete temperatures at the time of placement,
small nominal aggregate size and rapid moisture loss due to hot, dry and/or windy weather
conditions during placement and curing. Cracking due to temperature and moisture
fluctuations can also be expected. The use of low slump concrete (not exceeding 4 to 5
inches at the time of placement) can reduce the potential for shrinkage cracking.
9 Leighton
~~
a
O
0
O
a
a
O
a
0
0
110231-024
September 24, 2003
Future homeowners and homeowners'. association should be made aware of the importance of
maintaining a constant level of soil moisture. Homeowners should be made aware of the
potential negative consequences of both excessive watering, as well as allowing soils to
become too dry.. hnproperly designed, constructed, or maintained planters often pond water .
and cause deep moisture penetration and soil moisture change. Since deep and repeated soil
moisture change can damage the adjacent structure, placement of planters adjacent to
foundations or other sensitive hardscape, such as pools and spas, should be discouraged if
adequate and proper maintenance can not be assured.. Our recommendations assume a
reasonable degree of homeowner responsibility, if the homeowners do not adequately
maintain correct irrigation and drainage, some degree of foundation movement should be
expected. However, this movement typically does not cause structural damage, but will cause
such things as stucco cracking and dry wall separation.
The slab subgrade soils should be presoaked in accordance with the recommendations
presented in Table 1 prior to placement of the moisture barrier and foundation concrete.
We recommend a minimum horizontal setback distance from the face of slopes for all
structural footings (retaining and decorative walls, building footings, pools, etc.). This
distance is measured from the outside bottom edge of Ure footing horizontally to the slope
face (or to the face of a retaining wall) and should be a minimum of H/2, where H is the slope
height (in feet). The setback should not be less than 5 feet and need not be greater than 10
feet. Please note that the soils within the structural setback area possess poor lateral stability
and improvements (such as retaining walls, sidewalks, fences, pools, patios, etc.) constructed
within this setback area may be subject to lateral movement and/or differential settlement.
The potential for distress to such improvements may be mitigated by providing a deepened
footing or a pier and grade-beam foundation system to support the improvement. The
deepened footing should meet the setback as described above. Modifications of slope
inclinations neaz foundations may reduce the setback and should be reviewed by the design
team prior to completion of design or implementation.
5.4 B4nicture Seismic Design Parameters
Stnrctures should be designed as required by provisions of the Uniform Building Code (UBC)
for Seismic Zone 4 and state-of-the-art seismic design parameters of the Structural Engineers
Association of California. This site is located with UBC Seismic Zone 4. Seismic design
parameters in accordance with the 1997 UBC are presented below.. Please refer to the
Supplemental Geotechnical investigation (Leighton, 2001) for additional information.
_10_
Leighton
0
O
a
0
O
D
110231-024
SeptemtJer 24, 2003
Seismic Source Type = A
Near Source Factor, Ne =1.5
Near Source Factor, N~ = 2.0
Soil ProSle Type = So
Horizontal Peak Ground Acceleration = 0.688
(10% probability of exceedance in 50 years)
5.5 Corrosion
For sulfate exposure and cement type refer to Table 1 and the corresponding sections of the
LTBC. For other buried improvements a licensed corrosion engineer should be contacted in
order to determine the potential for corrosion if corrosion sensitive buried improvements
are planned.
The recommended lateral pressures for very low to low expansive soil (expansion index less
than 51) and level or sloping backfill are presented on Table 4 (rear of text). The onsite wall
excavation materials should be reviewed by the geotechnical consultant prior to use as wall
backfill.
Embedded structural walls should be designed for lateral earth pressures exerted on them.
The magnitude of these pressures depends on the amount of deformation that the wall can
yield under load. If the wall can yield enough to mobilize the full shear strength of the soil, it
can be designed for "active" pressure. If the wall cannot yield under the applied load, the
shear strength of the soil cannot be mobilized and the earth pressure will be higher. Such
walls should be designed for "at rest" conditions. If a structure moves toward the soils, the
resulting resistance developed by the soil is the "passive" resistance.
The equivalent fluid weights of Table 4 assume very low to low expansive, fi~draining
conditions. If conditions oU-er than those assumed above are anticipated, equivalent fluid
weights should be provided on a case by case basis by the geotechnical engineer. Surcharge
loading effects from adjacent stnutures should be evaluated by the structural engineer. All
retaining wall structures should be provided with appropriate drainage and waterproofing. The
outlet pipe should be sloped to drain to a suitable outlet. Typical wall drainage design is
illustrated in Figure 2.
Lateral passive pressures may be determined using the values provided in Table 4. In
combining the total lateral resistance, the passive pressure or the frictional resistance should
be reduced by 50 percent. Wall footings should be designed in accordance with structural
considerations. The passive resistance value maybe increased by one-third when considering
loads of short duration, including wind or seismic loads. The horizontal distance between
foundation elements providing passive resistance should be a minimum of three times the
-11-
Leighton
1~
110231-024
September 24, 2003
depth of the elements to allow full development of these passive pressures.. The total depth of
D retained earth for design of cantilever walls should be the vertical distance below the ground
surface measured at the wall face for stem design or measured at the heel of the footing for
overturning and sliding.
a Foundations for retaining walls in competent fomuQional soils or properly compacted fill
should be embedded at least 18 inches below the lowest adjacent finish grade.. At this depth,
an allowable bearing capacity of 2,250 psf may be utilized. The bearing capacity may be
increased by 250 psf for each additional six inches of embedment to a maximum of 4000 psf.
Wall backcut excavations less than 5 feet in height can be made near vertical.. For backcuts
greater than 5 feet in height, the backcut should be flattened to a gradient not steeper than 1:1
(horizontal to vertical). Backfill soils should be compacted to at least 90 percent relative
compaction (based on ASTM Test Method D155TJ. Backfill should extend horizontally to a
minimum distance equal to one-half the wall height behind the walls.. The walls should be
0 constructed and backfilled as soon as possible after backcut excavation.. Prolonged exposure
of backcut slopes may result in some localized slope instability.
5.7 Concrete Flatwork
a
0
0
0
0
Expansive soils are known to exist onsite and therefore concrete flatwork should be designed
and constructed with the anticipation of expansive soil related distress. Closer spacing of
control joints, reinforcement and keeping the flatwork subgrade at or above optimum
moisture prior to the placement of concrete may m;n;m;~e cracking and differential
movement.
City of Temecula Standard No. 401 "Sidewalk and Curb" specifies aggregate base or
approved select material under sidewalks and curbs when expansive soil is present. In lieu of
the aggregate base or select material under sidewalks and curbs, and with the approval of the
City of Temecula, the sidewalk and curb subgrade may be presoaked such that 120% of
optimum moisture content to a minimum depth of 8 inches is achieved prior to the placement
of concrete. Moisture testing must be performed by the geotechnical consultant prior to
concrete placement.
-12-
Leighton
~~
D
0
0
D
a
a
0
110231-024
Septernber 24, 2003
5.8 Control of Surface Water and Drainage Corrtrol
Positive drainage of surface water away from structures is very important.. No water should
be allowed to pond adjacent to buildings. Positive drainage may be accomplished by
providing drainage away from buildings at a gradient of at least 2 percent for a distance of at
least 5 feet, and further maintained by a swale on drainage path at a gradient of at least 1
percent.. Where limited by 5-foot side yards, drainage should be directed away from
foundations for a minimum of 3 feet and into a collector swale or pipe system.. Where
necessary, drainage paths may be shortened by use of area drains and collector pipes and/or
paved swales. Eave gutters also help reduce water infiltration into the subgrade soils if the
downspouts are properly connected to appropriate outlets.
Planters with open bottoms adjacent to buildings should be avoided, if possible. Planters
should not be designed adjacent to buildings unless provisions for drainage, such as catch
basins and pipe drains, are made. No ponding of water from any source (including
irrigation) should be permitted onsite as moisture infiltration may increase the potential for
moisture-related distress.. Experience has shown that even with these controls for surface
drainage, a shallow perched ground water or subsurface water condition can and may
develop in areas where no such condition previously existed. This is particulazly true
where a substantial increase in surface water infiltration resulting from site irrigation
occurs. Mitigation of these conditions should be performed under the recommendations of
the geotechnical consultant on a case-by-case basis.
5.9 Graded Slopgp
It is recommended that all slopes be planted with drought-tolerant, ground cover vegetation
as soon as practical to protect against erosion by reducing runoff velocity... Deep-rooted
vegetation should also be established to provide resistance to surficial slumping.
Oversteepening of existing slopes should be avoided during fine grading and construction.
Retaining structures to support graded slopes should be designed with structural
considerations and appropriate soil parameters provided in Section 5.6.
5.101<rtigation. Lands~capina and Lot Maintenance
Site irrigation should be controlled at all times. We recommend that only the minimum
amount of irrigation necessary to maintain plant vigor be utilized.. For irrigation of trees
and shrubs, a drip irrigation system should be considered. We recommend that where
possible, landscaping consist primarily of drought-tolerant vegetation. A landscape
consultant should be contacted for proper plant selection. For lazge graded slopes adjacent
to open space areas, we recommend native plant species be utilized and that irrigation be
utilized only until plants are well established. At that time, irrigation could be significantly
reduced.
-13-
Leighton
110231-024
September 24, 2003
Upon sale of homesites, maintenance of lots and common areas by the homeowners and
a homeowner's association, respectively, is recommended. .Recommendations for the
maintenance of slopes and property are included in Appendix D for your review and
distribution to future homeowners and/or homeowner's associations.
5.11 Post-Grading Geotechnical Review
5.11.1 Constroctlon Review -Construction observation and testing should be performed
by the geotechnical consultant during future excavations, utility trench baclcfilling
and foundation or retaining wall construction at the site. Additionally, footing
0 excavations should be observed and moisture determination tests of subgrade soils
should be performed by the geotechnical consultant prior to the pouring of concrete.
a
0
O
-14-
Leighton
5.11.2 Plans and Specifications -The geotechnical engineer should review foundation
plans to evaluate if the recommendations herein have been incorporated. Foundation
design plans and specifications should be.reviewed by the geotechnical wnsultant
prior to excavation or installation of residential development..
f~
a
a
0
O
a
a
a
0
0
110231-024
September 24, 2003
6.0
The presence of our field representative at the site was intended to provide the owner with
professional advice, opinions, and recommendations based on observations of the contractor's
work.. Although the observations did not reveal obvious deficiencies or deviations from project
specifications, we do not guarantee the contractor's work, nor do our services relieve the contractor
or his subcontractor's work, nor do our services relieve the contractor or his subcontractors of their
responsibility if defects are subsequently discovered in their work. Our responsibilities did not
include any supervision or direction of the actual work procedures of the contractor, his personnel,
or subcontractors.. The conclusions in this report are based on test results and observations of the
grading and earthwork procedures used and represent our engineering opinion as to the compliance
of the results with the project specifications.
This report was prepared for Lennar Communities, based on their needs, directions, and requirements
at the time.. This report is not authorized for use by, and is not to be relied upon by any party
except, Lennar Communities, with whom Leighton contracted for the work. Use. of or reliance on
this report by any other party is at that party's risk. Unauthorized use of or reliance on this
Report constitutes an agreement to defend and indemnify Leighton and Associates from and
against any liability which may arise as a result of such use or reliance, regardless of any fault,
negligence, or strict liability of Leighton and Associates.
-15-
Leighton
~$
Ohl - - ' ~~~ _.-,r _- ~- . ,'
_. l,, ._ __. _._ ._ - ~~, . __~ E
,f , `
'"-~ _
,F~ i r--
~ I
_ --. ~P... ._.._ `L ~ ~ i
1 ~ i ~ _
r . --__
.. ~_
__~_ _.
C _ I ~ _
f
f~` aye. °dq,. _- f~: ~ ~
r
• r"' _ ~ ~
,'
• _ ~~
T ~ ~~ ~.,~
Ir ,
Site Location -- -~ t'~
~~
._~ f .~-:
_-~
- - -~ ~ ~
__ ~ . . ti
-{~• A ' I
,
~°~ oa ~ 0 -
I
,-.., ,- I- - ~
. ~ ~ I -~-
- ~ -, , ;.~~~~~ w Rs'~
i ~`~ =~ - _
s~~
Base Map: The Thomas Guide Digital Edition Inland Empire 2000, Not To Scale
HarVeston Project No. ~
Tract 30667-1, $ITE LOCATION 110231-024
Temecula, California MAP Date
Riverside County, California September 2003 Figure No.1
~~
SUBDRAIN OPTIONS AND BACICFILL WHEN NATIVE MATERIAL HAS EXPANSION INDIX OF X50
OPTION I: PO'E SURROUNDED WITH
CLASS 2 PERMEAL0.E MATERIPL
W1TH PROPER
SURFACE DRAINAGE
SLAPE
OR LEVEL
lY
NATNE
WATERPROOFING
(Sff C~NERPL NOTES)
`.
12' MINIMUM
WEEP F1IXE
(SEE NOTE 5)
LEVEL OR
SLOPE
GENERAL N07ES:
CLASS 2 PERMEAaIE
FRTER MATERIAL
(SEE GRADATION)
4INCH DIAMETT3t
PERFORATED PD'E
(SEE NOTE 3)
OPTION 2; GRAVEL WRAPPED
IN FILTER FABRIC
WITH PROPER
SURFA~ DRAINAGE
SIOPE
OR IEVEL
IY
NATIVE
WATERPROOFING r.
(SEE GENERAL NQrES)
LEVEL OR
SLAPE
C~ 2 Rlher Permeable Material Gradatlan
Per Caltrans Spedfkallons
Sieve Sine PeroeM Pa~Ta
1• 100
3/4" 90-100
3/g° 40-100
Na 4 250
Na 8 18-33
Na 30 5-15
Na 50 o-7
Na 200 o-3
FILTER FABRIC
(SEE NOTE 4)
l2' MINPIIM
W ro 1Va INCB Siff
GRAVEL wWY'PED aT FILIER
FABRIC
* Wa[erproDFlng should be proNded where moLsbTre nuisance problem through the wall is undesi2ble.
* Water proofing of 111e wa1Ls is rpt under purview of the geotechniml engineer
* All drains should have a gradient of 1 percent rNnimum
*Outlet portlon of the subdreln should have a 4irlch diameter slid pipe discharged into a suitable disposal area designed by the project
engineer. The subdrain pipe should be aaessible for maintenance (roddirg)
*Other 5ubdrein bacld8l options are subject b the review by the geotedLnicel engineer and modification of design parameters.
Notes
1) Sand should have a sand equivalent of 30 or greaterarM may be dertsif'red bywatPrjettlrg.
2)1 Cu. ft. per ft. of 1/4- b 1 1/2-inch sine gravel wrapped in filter fabric
3) Pipe type should be ASTM D1527 Aaylanftdle Butadiene Styrene (ABS) SDR35 or ASTM D1785 Polyvinyl Chloride plastlc (PVC), Shcedule
40, Amwo A2000 PVC, or approved equivalent. Pipe should be installed with perforations down. Perforations should be 3/8 irxtr hL
diameter placed at the ends of a 120-degree arc in two rows at 3inch on center (staggered)
4) Rlter fabdc shaukl be Mirafi 140NC or approved equivalent
5) Weephole should be 3-Inch minimum diameter and provided at 10-foot nL~dmrmL intervals. If exposure B pertnithed, weepholes should
be located 12 Inches above finished grade. If exposure is not permitted sLx:It as far a wall adjaarrt b a sidewalk/curb, a pipe under the
sidewalk to be discharged through the curb face or equivalent should be prDNded. Tor a basgnatt-type wall, a propersubdrain outlet
system should be provided.
6) Ruining wall plans should be reviewed and approved by the geotechnical engirLcer.
7) Walls over six feet in height are subject to a special review by the geotechnical ergirteer and modifiratlarLS b the above requirerrwtts.
~ RETAINING WALL BACKFILL AND SUBDRAIN DETAIL
FOR WALLS 6 FEET OR LESS IN HEIGHT
WHEN NATIVE MATERIAL HAS EXPANSION INDEX OF <50
i Figure No. 2.
20
a Ng
Q N
O~
D
0
a
0
O
O
D
gy d N d
' N
'~ N
U d
o ~
~ d
U d
U N
U N
U N
U N
~ N
~ N
A
'I,+' `
pp,, U v c
i U
A 00
'r 00
'r 00
..~ 00
.--i 00
.r 00
.r 00
rr 00
.-i 00
.--~ 00
.--i 00
.--i 00
.r 00
.--~ OD
.r
N w N V N N Y Y ~! Y ~+ V Y i~
~
O
O O
O O
O O
O O
O O
~ O
~ O
~ d
O O
~ O
O O O O O
O
N O
N O
N O
N O
N O
N O
N C
N O
N O
N O
N O
N O
N O
N
.~. .. .-. r+ ~ .. .. .--i 'r .r .--i ..y ..~ .r
O
~ d .--.
Yw~
~
..
~ ,
~
M yy ~y
v
LL ~ O~ ~ M .-~ .~-~ ~--i ~ ,fir ~O M M V1 l~ M M
N
~aA
'~
C.
U
~
r.
~ ~ c ~ ,~
~ a
~ M
d
Y C O
U x
~ O
~
H ~ y
CO y ~
N N y
~ }y iN
O
~-.
O
N
l~
a
O~
~
O~
~
~O
~
v~
V
.-.
V'
O
N
~
o0
N
~n
M
l~
M
.r
7
N
~
Ay
+O-, Q
~--~
~ w
~
w
0
1 N d d N N ~ ~ .-~. .~ ti .~ .~ ~ ~ .~ ti
~
O p
66 p
'6b A
'6b .a
'6b A
'~ A
'6b .O
'bb A
'6b A
'bb A
'bb ?
'6b A
'd~ A
'6h A
'bh .D
'6b
~ ~ a ~ '~ '~ ~a, 'ob '~ ~oo '~ ~ '~ ~'°oo ~~ ~ 'ob '~
`nw z z z z z z z z z z z z z z z
o:~
.~Wa ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~
z .-r N M V V1 ~O l~ 00 Q\ O
~ .~r
.. N
.. M
.. ~
.. h
..
..
s
N8
(QM1 N
N N
o~
H
D
O
a
O
0
0
a
D
a
a
c
'
~
~ w
~
U m
d
U y
~
~ m
d
U m
d
U m
d
V y
d
V y
~
V m
d
~ m
~
U m
d
U m
~
U m
d
'v yr
d
.
J~ J ~
r U
00 00 00 00 DO 00 00 00 00 00 00 00 W 00
~~~//
l
i~
i+
V
V
i~
V
i+
M~
Y
Y
Y
~+
N
•.i
F
,.~ ~
~~
O O
~ d
~ O
O O
O O
O O
O O
~ O
~ O
O O
~ O
~ O
O O
O C
~ 0
~ O O
N O
N O
N O
N O
N O
N O
N O
N O
N O
N O
N C
N O
N O
N
y .-. 'r .-i rr .--i ~ .. .--i .-w 'r .-r ~ ~ .--i
C
a
_,
+d-' .' N
~, w
q
.d 7 ~ U y
".
p~ N y
N
r+
vl
N
N
00
~D
M
N
~
h
~
N
~
7
p
td C4 ~ y v
a~
d
A
a
U
`~
~
~~ ~
W ~ ~ ~ .~ a
M $ ~j ~ o
~
H ~ $
Er ~ '~
v '^
Q~Q ~ w
~..i
'~
V
7
~
V
~
V'
~
V'
~
7
M
M
7
V'
.~
e
.k
r
~y r
~
"'
•VF• ,
.
W
W ~
O
N ~ ~ ~ ~
N ~ ti
~ ti
~
~ ti
~
~
~
~ ti
~
~
~
~ ti
p
~
~
~ ti
p
~ ~
~
~
~ ~
~ ~
~ ~
~ ti
e~
RI
N ~ ~ ~ ~ ~ ~ ~ ~ ~ ~~ ~ ~~ ~~ ~~ ~~
ti ~ a "o~ ~ o'~ en 'ob ou "~ on "~ on 'ob o"b '~ o0 o"b
~ ~ fii z z Z z z Z z z z Z z z z z z
.
~
p
`.d
~ q^
p
~ ~ '~ ~ '~ ~ ~ ~ ~ ~ ~ ~ '~ ~ ~ '~
,
wWa° ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~
P
'~„ ~O
.-i l~
~+ QD
~--~ Q1
~-+ O
N .--~
N N
N M
N d'
N V7
N ~O
N l~
N W
N O~
N O
M
2~
N O
C? N
H
a
0
a
a
a
a
O
D
V U V U U
',~
~ A W W 00 00 00
~ ~ ~ .. .. ~
.: .: .: .:
~ ~
: 0 o o e ° e ,
N N N N N N
~ ~ .. ~ ~
0
~
a
°' w H
~ ~ ~ ~
~
i
~ b b h l~ M
pp
t0
O j" N w.i
fl~
~~ A
Q
O
U q
-.
~ c
~ ~ ,~
~
,o ~ a
o
M U ~ c
~(
Ur
Fn ~ ~
V N /",
~ ~ ~
~
W
M
M
7
.~
~
M
~
N
a
~ ~..+
U
p
a
C~ w
w
0
~'1
a {~~
~
~
~
~
~
W ~ ~ ~ ~
ti ~
0
~ ~
S w z z z z z z
~
.
N d
~
~Cj ~^X ~`~Y
y
H .~.
M N
M M
M 7
M V1
M ~O
M
Q
1
ti H
ti ti
~~
UU
~~
~y~y
N W
~ N
0
a
0
a
O
110231-024
September 24, 2003
TABLE 2
Minimum Conventional Foundation Design Recommendations
UBC Expansion Potential
Very Low to Low Median
1-Story. Footing Depth of Embedment (Exterior and 18"
Interior (Exterior and Interior)
2-Story Footing Depth of Embedment 18" Exterior 18"
12" Interior xterior and Interior
Isolated Column Footings Exterior of 18" 24"
Minimum Foundation
Presoaking See Table 1
No. 3 rebaz placed at No. 3 rebaz placed at
mid-slab height mid-slab height spaced
Minimum Slab Reinforcement spaced 18 inches on 15 inches on center
Thickness
center, each way; ,
each way; minimum
minimum slab slab thickness 5 inches
thickness 4 inches
Two inches of sand over a 10-mil polyvinyl
Underslab Treatment membrane (Visqueen or equivalent) over an
additional two inches of sand
Notes:
(1) Depth of interior or exterior footing to be measured from lowest adjacent tmish grade. If
drainage swale,~lowline elevation is less than S feet laterally from footing, footing bottom
to be minimum 6 inches below Swale flowline
(2) Living area slabs should be tied to the footings as directed by the structural engineer.
(3) Garage slabs should be isolated from stem wall footings with a minimum 3/8" felt expansion
o joint.
(4) Underslab treatment sand should have a Sand Equivalent of 30 or greater (e.g. washed
concrete sand).
(5) The lower two inches of underslab treatment sand maybe omitted on lots which possess a
very low potential (see Table 1).
2v
0
0
a
O
O
a
a
O
0
110231-024
September 24, 2003
TABLE 3
Minimum Post-Tensioned Foundation Design Recommendations
Expansion Potential (IIBC 18-2)
Design Criteria Very Low Low Medium High
EI= 0.20 EI= 21-50 EI= 51-90 EI = 91-130
Edge Moisture Center Lift: 5.5 feet
Variation, em Edge Lift: 3.0 feet
Differential Center Lift: 1.25 inches 2.0 inches 2.4 inches 4.5 inches
Swell, ym Edge Lift: 0.4 inches 0.4 inches 0.8 inches 1.3 inches
Modulus of Subgrade Reaction (k) 150 psi/in 125 psi/in 125 psi/in 100 psi/in
Plasticity Index Non Plastic *
Minimum Perimeter Footing 12 inches 12 inches 18 inches 24 inches
Embedment Depth
Two inches of sand over a 10-mil polyvinyl membrane
Underslab Treatment (Visqueen or equivalent) over an additional two inches of
sand.
Presoaking See Table 1
(1) Depth of exterior footing to be measured from lowest adjacent finish grade or drainage Swale
flowline elevation (less than 5 feet laterally from footing, per code).
(2) Living area slabs should be tied to the footings as directed by the structural engineer.
(3) Detailing of expansion crack control joints for PT slabs per structural engineer.
(4) Underslab treatment sand should have a Sand Equivalent of 30 or greater (e.g. washed concrete
sand).
(5) The lower two inches of underslab treatment sand may be omitted on lots which possess a very
low expansion potential (see Table 1).
(6) Potential total and differential settlement should be included cumulatively with differential swell
parameters.
* Plasticity index to be provided upon request if a ribbed UBC type (Section 1815) slab is preferred.
D ~~
a
a
a
a
0
0
0
110231-024
September 24, 2003
TABLE 4
Lateral Earth Pressures'
For Ve . Low bo Low nslve Soil Badd•ill
Equivalent Fluid Weight (pct
Conditions
Level Baclsfdlz 2:1 Slope Backtill
Active 45 67
At-Rest 65 95
Passive3 300 125 (Sloping Down)
Assumes drained condition (See Figure 1)
ZAssumes a level condition behind and in front of wall foundation of project.
3Maximum passive pressure = 4000 psf, level conditions.
4Assumes use of very low to low expansive soil (EI= 0.50).
o ~~
O
110231-024
September 24, 2003
APPENDDCA
U
0
O
0
O
O
O
0
" - California Geologic Survey (CGS), 2003, the Revised 2002 California Probabilistic Seismic
Hazard Maps, June 2003. By, Tianging Cao, William A. Bryant, Badie
Rowshandel, David Branum, and Christopher J. Wills.
Leighton and Associates, 2001, Supplemental Geotechnical Investigation and Geotechnical
Review of 100-Scale Mass Grading Plan, Tentative Tract No. 29639,
Harveston, Temecula, California, LDOI-058GR, Project No. 110231-003,
dated August 15, 2001.
Leighton and Associates, 2003, As-Graded Report of Mass Grading Harveston, Tract 29639-1, City
of Temecula, California, Project No. 110231-006, dated February 5, 2003.
Naval Facilities Engineering Command, 1986x, Soil mechanics design manual 7.01, Change 1:
U.S. Navy, September.
Naval Facilities Engineering Command, 1986b, Foundations and earth structures, design manual
7.02, Changes 1: U.S. Navy, September.
RBF Consulting, 2003, Harveston Tract 30667, -1, -2, and -3 Rough Grading, August 2003,
LD03-023GR, Sheet 3 of 6.
A-1
Leighton
io
io
is
D
D
is
io
io
io
10
ID
ID
10
io
io
ID
0
D
D
110231-024
September 24, 2003
j~nlanation of Summary of Field Density Tests
A: Retest of previously failing compaction test.
B: Second retest of previously failing compaction test.
Compaction tests taken during mass grading of site unless indicated by:
FG: Compaction tests taken on rough finish grade.
SF: Compaction tests taken on slope face.
Test Location: Indicated by lot number.
Test Method:Compaction test by Nucleaz Gage (ASTM 2922) unless indicated by
S: Sand Cone Method (ASTM 1556).
Test Elevation: Approximate elevation above mean sea level.
B-1
0
0
0
a
r
N
r
W
ao
J
LL
a°
a a
0 N
0
D
a
O
a~
-, o
e~
yya
W U
.- o~n~nv,ooooooooo~nv~~nov,oov,v,oooo~nv~v,~noo
e y odooo.........o0.:.:06.:oooao-:vioo-:a~viooooo~o~.
d
~ 'b .~ 00 O 00 O .~ .+ h 00 R .~ n h M n v N ~/1 Moo N N n Vl ~ N H1 b b .-~ Vt o0
Fi ~ O~ ~G t~f fV C ^ M ~ W ~N.•i N O~ 00 O. 00 O~ .N.•i O~ h '+ O. T M ~G V1 O~ O~ O~ C .~.•i Vf
.ti .+ .+ .r .r ...~ N .r .r .ti .r .r .+
N 0000 ~n v~ v~v~ O~n V10 x/100000 v1000~/1000000000
a1 V1 ~O ~G ~G a0 00 00 00 N o0 00 N o0 ~C ~D ~G aG ~G 00 ~ ~C ~G 00 00 ~ ~ ~C ~G ~C ~G aG o0
~y M~~~ N N~ N -M N N M N N N~ O~~~~~~ O~~~ N N N O O
~Lii ..w .~ .4 .w .ti .~ ..+ .ti .-i ..~ .r ...i .ti .r .y
~^ 00b W OMMOwtb7O~bbnOVl ao O~ao7b bl~o00 V1 O~t~oO ~Db
y fV M ~ ~ 00 [~ eV ~G .~-' .~ O .~.' .~-' fV .M..i M C ~ W .-i ti n O~ b .n+ W ~ V
.Na .~-~ .~.i .~.~ .~n .N+ .Ni ~ .Ni .~i .tea .~.i .Na O O O ....~ .. C
Q .-w
'+ O V~ 0 0 0 0~ 0 0~ 0~ V~ b~ O M~~ O b M M~ 7 V V b b
N b 01 O~ 00 0p 01 M M~~ O n 0 N M ~/1 O~ O~ n M M y
~ 0 0$ 01 ~ Q1 0 0 0 ~ 0 0 0 0 0 .~ ~ 0 0 0 0 0 0~ 0 0 0 0 0 0 0
~~...G....G...~__...__~~ .............._~~..~........_
F
w
~ I
O ~OOO7n0vf ..R M b V1~MN O
N N M '+ N '+ M N n Q~ M 00 00 '+ N M h M M M M M M M M 7 Vf b b n
e
~w
F+, O
FA
F Z
~iwU~`'v`Cwi~i~icwi~Cwicwi~i~'i~i~iwwwwwwwwwww~U`w~wcwiw
M M M M M M M M M M M M M M M M M M M M M M M M M M M M M M M M
O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O
O^~ ti b ~U b~~ ~D a a~~~ N N N N N N N N N N N N N N N N N
i i i i i i r i n i iii ~ ~ i i i n n n n n i i i r ~ i i i i
nmvvlbna00.+NM boooaoMR V1 Vlbnoo0~07nooQ~Onoo
"~~. M.. M. ~ v v v v~ v v v v i v i~ b~. b. e:°. n. n~~~ m w 0 0
.. ...... .... ..
N
w
0
a
a.
~~
Z
N 0 r
W U
M ~ W
= W
SM~
L 0
O ~''
A
Z Z J
QI YI 01 C
'p ` 6f
a a dv
.~
0
0
a
O
a
O N
`Nr
r
Z
O
J
O W
LL
LI.
O
~a
y
O
a
ee
~~ aa~~~~~~~~~~~~~~~~~~~~~~~~
a
de
a~
~- env,oooov~~n~n~n~nv,~nv,~nooov,oooo000
p 6 CO~~O.~000OCOCCO~v1~00~0. O~T.Q.^^
.~ 0 ..... .. .r ..r .ti .r
d
.~'~ .+rna hONI~OI~e+f MfM NI aO ao Q~..a 00 .~toN Nf~O V
F. ~ C 00 .~.•i ~ O~ .~.•i C O. t~ l~~ Vi ~G .'+. 1~ .V1..V1+ .w1. b ^ .a. N N N N N
M O O O O O O O O O O O O O O O O O O O O O O O O O O
ttl ~C ~G oo ~ ao ~ ~C ~C ~C ~G ~C ~G ~G ~G ~C ~ R ~ ~O o0 oG o0 00 00 00 00
~ty N N O O NN ^ ^ NN ~.N. ^.+.+~ ~ 0000000
eq //.. ..+ ..r .ti .r .+ .y .+ .r ..+ ..+ ...i ..~
O
~~p 0onaoo v,0oo...v, vi l~v, .. Sao o~v, ~n t~.. en aoa m~nn
L y .M.•i .N.NnMn N.~.~h~~~fV TC.Ni aOMO~Qi 1~n W
i ~i OOOO.N.~ ..~. .+.. ~ O~ T 00~0~ O. O. O~
VI ~ ~~benbmQ~~~~~~~~MM~ V bbbbbbb
h Vl n b b O~ O .~ N N ~/1 M M O~ O .+ N N
O O O O O ~ S O O O O O O O~~ O O D S O S O 0 0
.•r..~.. ~ .~.. ~ ...............................
~ .r ... ..........-.....-....
r
F
w
I~l I ~a~^~~NNNNNNNN... ~~M.~.~.NNN.Q. ~~~
0
a
0
FO
FA
Hz
wwwvivF`i~"iwwwwwwwaiwwwwwwwwwv~.ww
M M M M M M M M M M M M M M M M M M M
O O O O O O O O O O O O O O O O O O O M M M M M M M
~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ O O O O O O O
vvvvaa~a~avvvavvaaaarn :~ :~
N N N N N N N N ~`1 N N N N N N N N N N
iiii nnni ~i ii ~i ni i i i 00000 000
T O .+ N M O V1 ~O 00 O. O N M N M h ~D O N M Vt ~O
~TO~ Q~ a.~i .~i .0. .~i ^ 000070 ~ V ~ OD 000000 ~ DO W
.ti .M- .Ma .Mi .Mi M .Mi .M+ .M+ .M..M..M. Mi .M..M+-~ .M..M.
~~
.°3
O v~~
N
a
a d
z
og
° w U
°¢w
~_~
e
O
m ~
~ m v
Z Z J
m m e
V V ~ m
a a av
O 110231-024
September 24, 2003
0
APPENDD(C
Lataratorv Testing Pr~oaedun~ and Test Results
., Exnansion Index Tests: The expansion potential of selected materials was evaluated by the
Expansion Index Test, ASTM test method D4829 or U.B.C. Standard No. 18-2. Specimens are
molded under a given compactive energy to approximately the optimum moisture content and
approximately 50 percent saturation or approximately 90 percent relative compaction. The
prepared 1-inch thick by 4-inch diameter specimens are loaded to an equivalent 144 psf surcharge
and are inundated with tap water until volumetric equilibrium is reached. The results of these tests
are presented in the table below and in the soil characteristics table herewith Appendix C:
O
a
a
0
Sample Location Sample Description Expansion
Index Expansion
Potential
Lots 1-5 Dazk olive brown lean SILT 53 Medium
Lots 6-10 Dazk olive brown lean CLAY 55 Medium
Lots 11-15 Dazk olive brown lean CLAY 78 Medium
Lots 16-19 Dazk olive brown lean SILT 58 Medium
Lots 20-22 Light brown sandy lean SILT 76 Medium
Lots 23, 24, 35, & 36 Dazk olive brown lean SILT 57 Medium
Lots 25-29 Dark olive brown lean CLAY 83 Medium
Lots 30-34 Dazk olive brown lean SILT 51 Medium
C-1
M
a N
qg H a
~ N ~" ~
0 ~ ~ v~ .5
~ .~
~a
U M
O ~
.~
F
a~u ~~
S~ w°
3~
,~ U
~~
~~
y
~ ~~_°
.gam
q ~ .`Y
U ~ ~
'4~
~~
p ~ ~ ~
b b
3 ~
Y
~~ «q. ~
.~ .0. O
0 .~~~
Y
~ .~
~~
0 ~~~
U
n
m
a ~ y-. A
o A~
~~~
O V] r b
V i! U U U
N ~ ...
a q
z q
z q
z q
z
W r'" ~ ~ ~ ~
ypypO
N ~
V~'1
~
N
~
N
~
d'
W
~'
w z z z z z z z
~~~ ~ ~ ~ ~ N
3~~vo 3 0 0 0 0 0 0 0
Y
.~ ~ o
~
~
ma
O
0
O
0
O
O
N
•
V1
O
O
O\
~ ~
/-. U ,
y 0 0 N ~
-
i
+'~' ~ v~ o 0 0 0 0 0 l
~~ ~ A~ N M M O .~. N O ~
/-~
I
o U
H
~ ,
a
b
C
~ ~ ~~ ~ ~ ~
~ F O
~ U
~ 'd y
d V
~ U ~
w+ ~
~
A T '
~
m N .~-i
.~04 p
ad'
~ ~
O
~' F1
3 fA
..~
~
c3
A c
A c
A a ~ ~ o.
T ~ v1
~--~ 00
.--i O
M 'r
M ~ N ~
1p
H i
N
U
0
O
110231-024
September 24, 2003
APPENDD( D
Development areas, in general, and hillside lots, in particulaz, need maintenance to continue to
function and retain their value. Many owners are unaware of this and allow deterioration of the
property. It is important to familiarize owners with some guidelines for maintenance of their
properties and make them aware of the importance of maintenance.
Some governing agencies require hillside property developers to utilize specific methods of
engineering and construction to protect those investing in improved lots or constructed homes.. For
example, the developer may be required to grade the property in such a manner that rainwater will
be drained away firm the lot and to plant slopes so that erosion will be min;m;~ed. They may also
be required to install permanent drains.
O However, once the lot is purchased, it is the buyer's responsibility to maintain these safety features
by observing a prudent program of lot care and maintenance. Failure to make regular inspection
O and maintenance of drainage devices and sloping areas may cause severe fmancial loss. In addition
to their own property damage, they may be subject to civil liability for damage occurring to
neighboring properties as a result of his negligence.
The following maintenance guidelines are provided for the protection of the owner's investment.
a a) Caze should be taken that slopes, terraces, berms (ridges at crown of slopes) and proper lot
drainage are not disturbed. Surface drainage should be conducted from the rear yard to the
street through the side yard, or alternative approved devices.
0 b) Tn general, roof and yard nmoff should be conducted to either the street or storm drain by
nonerosive devices such as sidewalks, drainage pipes, ground gutters, and driveways. Drainage
D systems should not be altered without expert consultation.
0
0
0
0
c) All drains should be kept cleaned and unclogged, including gutters and downspouts. Terrace
drains or gunite ditches should be kept free of debris to allow proper drainage. During heavy
rain periods, performance of the drainage system should be inspected. Problems, such as
gullying and ponding, if observed, should be corrected as soon as possible.
d) Any leakage firm pools, water lines, etc. or bypassing of drains should be repaired as soon as
practical.
e) Animal burrows should be eliminated since they may cause diversion of surface runoff,
promote accelerated erosion, and even trigger shallow soil flowage.
D-1
O 110231-024
September 24, 2003
a
f) Slopes should not be altered without expert consultation.. Whenever a significant topographic
Q modification of the lot or slope, is desired a qualified geotechnical consultant should be
contacted.
O g) If the owner plans to modify cut or natural slopes are proposed, an engineering geologist
should be consulted. Any oversteepening may result in a need for expensive retaining devices.
O Undercutting of aloe-of--slope would reduce the safety factor of the slope and should not be
undertaken without expert consultation.
0 h) If unusual cracking, settling or earth slippage occurs on the property, the owner should consult
a qualified soil engineer or an engineering geologist immediately.
0 i) The most common causes of slope erosion and shallow slope failures are as follows:
• Gross neglect of the care and maintenance of the slopes and drainage devices.
0 inadequate and/or improper planting.. (Barren areas should be replanted as soon as
possible.)
0 Excessive or insufficient irrigation or diversion of runoff over the slope.
j) Hillside lot owners should not let conditions on their property create a problem for their
neighbors. Cooperation with neighbors could prevent problems, promote slope stability,
adequate drainage, proper maintenance, and also increase the aesthetic attractiveness of the
O community.
k) Owner's should be aware of the chemical composition of imported soils, soil amendments, and
D fertilizers to be utilized for landscaping purposes. Some soils, soil amendments and fertilizer
can leach soluble sulfates, increasing soluble sulfate concentrations W moderate or severe
concentrations, negatively affecting the performance of concrete improvements, including
D foundations and flatwork.
D
D
0
D
3`
Q D-2