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Monrovia, California 91016-350C
TT (818) 930-1200
FAX (818) 930-1212
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Celebrating 50 Years of Dedication in Engineering and Environmental Sciences
GROUNDWATER SEEPAGE INVESTIGATION
South Side of Ambushers Street
Portion of Tract No. 34160
Diamond Bar, California
PREPARED FOR
City of Diamond Bar
21660 East Copley Drive
Suite 100
Diamond Bar, California 91765-4177
CCW Project No. 95-31-281-01
May 14, 1996
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A Wholly Owned 5uhsidary of
The Converse Professional Group
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CONSULTANTS
spthkmiversary
May 14, 1996
222 Last Huntington Drive, Suite. 211-A
Monrovia, California 91016-3500
818) 930-1200
FAX (818) 930-1212
http://www.converseconsultants.com/
Celebrating 50 Years of Dedication in Engineering and Environmental Sciences
Department of Public Works
City of Diamond Bar
21660 East Copley Drive
Suite 190
Diamond Bar, California 91765-4177
Attention: Mr. David G. Liu
Deputy Director of Public Works
Subject: GROUNDWATER SEEPAGE INVESTIGATION
South Side of Ambushers Street
Portion of Tract No. 34160
Diamond Bar, California
CCW Project No. 95-31-281-01
Gentlemen:
This report presents results of a geotechnical investigation performed by Converse
Consultants West (Converse) concerning water seepage on the south side of Ambush-
ers Street between Woodhill Circle and 20914Ambushers Street (approximately 1200
L.P.). This study investigated the groundwater infiltration and seepage conditions at
the subject location and provides remediation measures to mitigate distress conditions.
Geotechnical services for this project were performed in accordance with our revised
proposal dated December 1, 1995, as authorized by Mr. George Wentz on January 15,
1996, with the City of Diamond Bar Purchase Order No. P-3906.
Water was not encountered in the two borings drilled on Ambushers Street to a depth
of 21 feet. No evidence of significant pavement distress was observed on the street.
Fill soils were encountered in the borings to depths of 3 to 7.5 feet below the street
surface. Natural soils, siltstone and sandstone bedrock of the Puente formation were
encountered beneath the overlying fill soils.
The problem consists primarily of nuisance groundwater discharge from private hillside
properties running down the gutters to storm drains located near the bottom of the
street. Most of the water discharge is from surface runoff and an extensive series of
buried subdrains beneath the graded slopes which convey groundwater to the surface
throughout the year.
A Wholly Owned Subsidary of
The Converse Professional Group
City of Diamond Bar
CCW Project No. 95-31-281-01
May 14, 1996
Page 2
Many of the surface drainage devices on private properties along Ambushers Street
appeared to be poorly maintained and neglected. The drains were blocked with weeds
and slope debris, causing ponding and poor drainage conditions.
Remediation measures to mitigate the observed distress conditions are presented in
this report.
Thank you for the opportunity to be of service on this project. If you should have any
questions or if we can be of additional service, please do not hesitate to contact us.
We look forward to our continued involvement on this project.
Respectfully submitted,
CONVERSE CO
Mark B. -ScNuter, C
Senior Geologist
Ai.
Do Mar, RCE 35064
Project Engineer
Dist: 6/Addressee
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ANTS WEST
5 Leonard T. Evans, Jr., h.D., GE 302
Vice President/Chief Engineer
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No. 35064
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TABLE OF CONTENTS
GROUNDWATER SEEPAGE INVESTIGATION
SOUTH SIDE OF AMBUSHERS STREET
PORTION OF TRACT NO. 34160
DIAMOND BAR, CALIFORNIA
CCW Project No. 95-31-281-01
Page
1.0 INTRODUCTION ......................................... 1
2.0 SCOPE OF WORK ...................................... 2
3.0 SITE OBSERVATIONS .................................... 3
4.0 SUBSURFACE EXPLORATION .............................. 5
5.0 MITIGATION AND MAINTENANCE RECOMMENDATIONS ........... 6
5.1 Mitigation Alternatives ............................... 6
5.2 Pavements ....................................... 7
5.3 Slope Protection and Maintenance ....................... 8
6.0 CLOSURE ........................................... 10
DRAWING 1, "APPROXIMATE LOCATION OF TEST BORINGS 9 & 10"
SITE PHOTOGRAPHS 1 THROUGH 6
APPENDIX A, "FIELD EXPLORATION"
APPENDIX B, -LABORATORY TEST PROGRAM"
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1.0 INTRODUCTION
This report presents results of a geotechnical investigation performed by Converse
Consultants West (Converse) concerning water seepage on Ambushers Street in
Diamond Bar, California. The purposes of this investigation were to evaluate existing
groundwater infiltration and seepage conditions at the subject location and provide
remediation measures to mitigate distress conditions.
This report was written specifically for Ambushers Street described in the following
section, and is intended for use by the City of Diamond Bar and its design
professionals. Since this report is intended for use by the designer(s), it should be
recognized that it is impossible to include all construction details in this report at this
phase in the project. Additional consultation may be prudent to interpret these
findings for contractors, or possibly refine these recommendations based upon the
final design and actual conditions encountered during construction.
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2.0 SCOPE OF WORK
The scope of geotechnical services performed for this project included a review of
existing reports, obtaining Los Angeles County well permits, geologic mapping,
exploratory borings, geotechnical laboratory testing, geotechnical engineering
analyses, and preparation of this report. This report does not include an evaluation
of slope stability or the potential for soil and/or groundwater contamination at this site.
More specifically, the scope of work included the following tasks:
A review was made of the City of Diamond Bar Building Department files
for information and reports on the subject site.
Los Angeles County well permits were obtained for the proposed
monitoring wells.
Geologic reconnaissance mapping was performed at the site to visually
identify potential sources of water, identify all affected property
frontages in the study areas, estimate the quantity of water, and map the
underlying geologic materials.
Two borings were drilled to depths ranging from 11 to 21 feet below the
existing ground surface at the locations shown on Drawing 1. Sub-
surface conditions encountered in the borings were continuously logged
at the time of drilling. A more detailed description of the field exploration
procedures and exploration logs are presented in Appendix A, "Field
Exploration."
Geotechnicai laboratory tests were performed on selected earth material
samples. Tests include in -situ moisture and density, sieve and R-value
testing. Descriptions of the individual tests and test results are
presented in Appendix B, "Laboratory Test Program."
Analyses were performed and geotechnical recommendations were
developed as presented. Our findings and remedial recommendations
developed during this investigation are documented in this report.
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3.0 SITE OBSERVATIONS
Ambushers Street is located at the southern edge of the City of Diamond Bar. Review
of City grading files for Ambushers Street indicated that the street was originally
graded as part of Tract 34160 in 1978. The project site consisted of hillside terrain
which was graded into terraced building pads by cutting the hillside ridges and filling
the side canyons, as shown on Drawing 1. Slope areas between the building pads
were constructed at gradients of 1.5:1 (horizontal:vertical). Concrete terrace drains
were constructed on the slopes and convey water to the street gutters through side
yard drains. A fill canyon with a mapped canyon bottom subdrain extends northward
across the project study area. Subdrain systems were also installed behind the
buttressed fill slopes to relieve potential hydrostatic pressures from groundwater
seepage.
Review of the Grading Plan for Tract 34160 dated November 30, 1978 (Drawing 1)
and the Rough Grade Soils Engineering and Geologic Report for Tract 34160 dated
November 30, 1978, prepared by S. E. Medall and Associates, Inc., indicated that at
least ten separate subdrain systems were installed behind buttress fill slopes and in
the canyon bottoms during original tract grading in 1978. The subdrains were
designed to collect subsurface groundwater and seeps and prevent hydrostatic water
pressure build-up within the fill soils. The subdrains were reported to have consisted
of 4-inch-diameter perforated pipe buried in filter material. The subdrains were
installed at the heels of stabilization buttresses and at vertical intervals of 15 feet.
Locations of the subdrains are shown on Drawing 1. Canyon subdrains were reported
to have consisted of 8-inch-diameter perforated pipes embedded in filter material.
The grading plan shows that some of the subdrain outlets were located on raid -slope
areas or at building -pad grades. Some of these drains do not appear to flow into non -
erosive drainage devices such as a terrace drain or street gutter.
Only two subdrain outlets could be located during our field observations. One
subdrain outlet was observed along Pasado Drive beneath the rear yard of 21015
Ambushers Street. This drain was observed to be producing water which ran across
the sidewalk into the street gutter. Green algae has grown in the street gutter
downslope the subdrain outlet. The second subdrain outlet was observed on the rear
yard slope of 21130 Ambushers Street. Water was seeping out of the drain and
running down the slope surface to the lower terrace drain. The drainpipe outlet was
partially obstructed with weeds and debris.
Other subdrain pipe outlets could not be located on the overgrown slope areas or
within fenced yard areas.
Groundwater discharge flow from these subdrain systems is directed towards the
street gutters along Ambushers Street. We observed groundwater discharge running
down the concrete gutter on the south side of the street, although minor surface flow
was observed along the north side of the street on and below Pasado Drive. Most of
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this water discharge on the north side of the street is from the drain outlets which
convey surface runoff and subdrain discharge from the rear yard slope drains to the
front yard street gutter (Photo 1). The cumulative surface -flow discharges down the
gutter and into the storm drain located at the bottom of the street near 20914
Ambushers Street. This discharge was estimated to be about five to six gallons per
minute (gpm). A dark green algae growth had established itself in the street gutter
and along the seepage areas. Fallen leaves and debris had washed down with the
water and created a small blockage near the storm drain grate.
Homeowners along the lower portion of Ambushers Street report that surface flows
are nearly constant throughout the year with peak flows occurring during and
immediately following the wet winter months.
Terrace drain systems located on the rear yard slopes of 21020, 21040, 21060,
21080, 21112 and 21130 Ambushers Street appeared to be poorly maintained.
These concrete terrace drains, down drains, and buried side yard drain systems were
constructed during original tract grading in 1978. Three levels of terrace drains
Terrace Drains 1, 2 and 3) were constructed on most of the subject lots, as shown
on Drawing 1. Additional terrace drain systems were located on the upslope prop-
erties along Woodhill Circle and Running Branch Road. These drainage -control devices
concrete terrace drains, interceptor drains, down drains, bench drains, catch basins,
drain pipes, and other drainage devices) are an integral part of the graded slopes and
play an important role in minimizing the potential for slope erosion and instability.
The terrace drain located above 21130 Ambushers Street was cracked near the catch
basin at the end of the slope (Photo 2). Surface runoff was observed entering the
cracked section of terrace drain, which could permit water to infiltrate into the slopes.
Weeds and plants have started to grow within the crack.
The terrace drains were also blocked with weeds, fallen trees, organic debris and slope
debris which had washed down from the slopes (Photos 2, 3, 4 and 5). Water flow
in the drains was slowed and in many cases partially blocked, causing ponding in the
channels. The ponded water was providing a habitat for breeding of bugs and
mosquitoes.
One section of Terrace Drain 1 had been converted into a garden with raised planters
by the homeowner whose property the terrace drain crossed (Photo fi).
No evidence of significant pavement distress was observed on Ambushers Street.
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4.0 SUBSURFACE EXPLORATION
Two 8-inch-diameter, hollow -stem auger soil borings were drilled on Ambushers Street
to evaluate subsurface conditions. The borings were drilled to depths ranging from
11 to 21 feet below street grade at the locations shown on Drawing 1. Boring 9 was
converted to a monitoring well. Boring 10 was logged, sampled, and checked for
groundwater, then backfilled and tamped. Soil boring logs are presented in Appendix
A.
The pavement at the boring locations was two inches thick. Beneath the pavement
was a five -inch layer of base. Fill soils were encountered in the two borings to depths
ranging from 3 to 7.5 feet below existing grade, as tabulated below.
TABLE 4-1
ENCOUNTERED FILL DEPTHS
Encountered fill soils consisted of clay with some silt and sand. The clay soils are
estimated to have a medium potential for expansion.
The natural soils consist of clays and are moderately stiff to stiff. Underlying the clays
are siltstone and sandstone at depths of 10.5 and 13 feet.
Groundwater was not encountered to a depth of 21 feet on March 25, 1996. A 2-
inch-diameter monitoring well was installed to check for groundwater. No ground-
water was observed in the well on May 3, 1996, when the water level was
rechecked.
Based on results of subsurface exploration and experience, variations in the continuity
and depth of subsurface conditions should be anticipated. Care should be exercised
in interpolating or extrapolating subsurface conditions between or beyond borings. Fill
depths are expected to vary between borings. Seasonal groundwater variations may
occur.
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5.0 MITIGATION AND MAINTENANCE RECOMMENDATIONS
Remedial repairs and maintenance are recommended to mitigate the observed
nuisance -water flow along Ambushers Street. Subdrain systems and terrace drains
located on upslope private hillside properties along Ambushers Street appear to be
doing their job in conveying drainage water to the street gutters, in spite of their
poorly maintained condition. The problem consists primarily of a constant flow of
nuisance -water discharge running down the street gutters to the storm drain catch
basins near the bottom of the street and the growth of algae and scum which forms
along the gutters. Most of the year -around nuisance -water flow is from the extensive
series of buried subdrains beneath the graded slopes. These subdrains and terrace
drain systems play an important role in conveying water seepage and runoff to the
street and in minimizing the potential for slope erosion and instability.
Possible alternative solutions to mitigate the algae and scum buildup in the street
gutters could include the following:
1. Street -sweeping the gutters weekly to control algae and scum growth.
2. Constructing additional storm drain catch basins farther up the street to
intercept nuisance -water discharge in the street gutters.
5.1 Mitigation Alternatives
Alternative 1 — Street Sweeping: Street -sweeping the gutters along
Ambushers Street on a weekly basis could be performed to control algae and
scum growth. The street sweeper would have to thoroughly brush the gutter
area to remove the algae and scum. Parking restrictions may be required along
the street so that vehicles would not block the gutter during sweeping.
The street -sweeping alternative would be a long-term maintenance solution and
could prove to be less cost-effective in the long run.
Alternative 2 — Additional Catch Basins: Additional storm drain catch basins
could be installed on Ambushers Street to intercept the nuisance -water
discharge in the street gutters. These catch basins should be located farther
up the street in the gutters near the terrace drain outlets which are producing
most of the year -around nuisance -water flow. One recommended location is
in front of 21020 Ambushers Street as shown on Drawing 1 .
Intercepting the nuisance water discharge closer to the upslope sources would
relieve the homeowners along the lower sections of Ambushers Street from the
constant nuisance -water flow along the street gutters and associated problems
of green algae growth, smell, slip hazard, and exposure associated with the
water flow.
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Storm drain catch basins are presently located in the street gutters in front of
20914 (west side) and 20917 (east side) Ambushers Street, and 3411 Wood hill
Circle. It could not be determined if the storm drain catch basin on Woodhill
Circle was connected to the catch basins on Ambushers Street. A new section
of buried storm drain pipe may be required to extend the storm drain farther up
Ambushers Street.
5.2 Pavements
No evidence of significant pavement distress was observed on Ambushers Street
within the study area. A pavement section of two inches of asphaltic concrete over
five inches of base material, as indicatead on the boring logs, is not of sufficient
thickness when overlying a subgrade with an R-value of 6. Should work be required
for installation of new storm drain pipes and catch basins, we have included the
following pavement design recommendations.
In the proposed pavement areas, the upper six to eight inches of subgrade soils should
be scarified, moisture -conditioned, and properly compacted. Soils should be com-
pacted to a minimum of 90% of the ASTM D1557-91 laboratory maximum density at
2% above optimum moisture content. The clayey subgrades should not be allowed
to desiccate prior to placing paving.
The minimum asphalt pavement sections are presented below in Table 5-1, "Asphalt
Pavement Sections - Ambushers Street." The pavement sections are based on Traffic
Index (TI) values of 4.0, 5.0, 6.0 and 7.0; and a subgrade R-value of 6 from laboratory
tests.
TABLE 5-1
ASPHALT PAVEMENT SECTIONS - AMBUSHERS STREET
Aggregate base should be compacted to at least 95% of the ASTM D1557-91
laboratory maximum density. Base materials should conform with Sections 200-2.2
or 200-2.4 of the "Standard Specifications for Public Works Construction" (Green -
book), 1994 Edition. To reduce the potential for premature pavement distress, it is
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important that final pavement grade be designed such that ponding on or adjacent to
the pavements is avoided. Pavement runoff should be directed to a suitable non -
erosion drainage device.
Where asphalt pavements meet concrete or existing pavements, the concrete and/or
asphalt should be sprayed with an SS-1 or CSS-1 emulsion. Proper asphalt compac-
tion next to concrete pavements, curbs and existing pavements is important to provide
a relatively impermeable contact between the two materials.
5.3 Slope Protection and Maintenance
Slope maintenance will be required to ensure satisfactory performance of the hillside
slopes through time. Drainage and erosion control are important aspects of slope
maintenance and play an important role in minimizing the potential for slope erosion
and instability.
Many of the surface drainage devices observed on the hillside slopes were poorly
maintained and neglected (Photos 1 through 6). These hillside slopes are owned by
individual private property owners who are responsible for maintenance. The less
accessible slope areas of the properties are often forgotten or neglected.
Homeowners should perform periodic inspections and maintenance of drainage devices
on their properties. Maintenance needs to be performed on the entire slope area. The
same slope terrace drain runs through as many as six different properties. Slope
maintenance associations could be set up to pool the resources of a group of
homeowners. In any event, periodic inspections and maintenance need to be
performed several times a year and at least once before the wet winter months.
Drainage -related items requiring continuing periodic maintenance throughout the year
include the following:
All drainage devices (terrace drains, interceptor drains, down drains, side yard
drains, subdrains, canyon drains, debris fences, catch basins, drain pipes and
drainage devices) should be kept clean of debris, obstructions and maintained
in good working order to provide adequate drainage for rear yards and slope
areas. Homeowners should be advised of the importance of maintaining
drainage devices on their property and adjoining parcels.
Overgrown trees, shrubs and vegetation should be periodically cut back to
permit unobstructed flow and access along drainage devices. Accumulated
slope debris, soils, weeds, etc., should be removed from drainage devices to
permit positive flow and prevent ponding. These debris materials should be
completely removed from the slopes, not just dumped down the slope. Cracks
and separations in the drainage devices should be cleaned, sealed, repaired
and/or replaced to prevent infiltration of water. The drains should be watertight
and not leak. The terrace drains and other drainage devices should not be used
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for gardens or other purposes, but should be kept free and unobstructed for
surface drainage.
Subdrain pipe outlets should be located, cleaned and checked for proper
operation and drainage. We were unable to locate many of the subdrain pipe
outlets shown on Drawing 1. Subdrain pipe outlets located on mid -slope areas
or yard areas at the toes of slopes should not be permitted to discharge on the
slopes but should be connected by pipes or non -erosive devices to nearby
drainage devices. Rodent guards should be installed to prevent nesting,
clogging or damage to drain lines. It is important that these subdrain pipes be
maintained and free of obstructions. All drainage devices should be
constructed in accordance with all City Building and Grading Codes.
Some erosion of the steep natural slope areas should be anticipated through
time. Periodic inspection and maintenance will be required.
Irrigation lines should be checked periodically for proper operation and the
presence of possible leaks. Irrigation of the slope surface should be carefully
controlled or discontinued during the wet winter months.
Any erosion damage should be repaired immediately in order that more serious
problems may be averted. Repairs should be made in accordance with City of
Diamond Bar guidelines.
Periodic inspections of the slope areas, terrace drains, and down drains should
be performed to check for cracking or distress due to the shrink -swell
characteristics of the clayey slope soils.
Rodent activity should be controlled to prevent water penetration and loosening
of the soil.
Care should be exercised to prevent loose fill from being placed on the slopes
or on the drainage devices.
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6.0 CLOSURE
The findings and recommendations of this report were prepared in accordance with
generally accepted professional geotechnical engineering principles and practice for
Southern California at this time. We make no other warranty, either express or
implied. Conclusions and recommendations presented are based on results of the field
investigation, combined with an interpolation and extrapolation of subsurface
conditions between and beyond borings. if site conditions or the assumed project
description appear to be different from those described in this report, this office should
be notified immediately.
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t. STRUCTURE
A \ - 1, s• ' 1 ' n S S• _ 1_' '!' ..a _ /. i - czvrc.
mcu,
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4_ - _ -__ — - -
r S t -1 i+ f- y / ;- ';!•_r. APPROXIMATE LOCATION OF
TEST BORINGS 9 & 10 NOTES: 1. Boring
No.
9 was drilled, logged and sampled to a depth of 21 Beet, scalp Protect No.
1"_ 809 then
converted to
a 2-inch diameter monitoring well. Ambushers Street Date 95-31-281-01 2. Boring No.
10 was drilled, logged and sampled to a depth of 11 feet, Diamond Bar, California 5/1MKT s Prepared 8y wingNothen backfilled and
tamped. MKT Checked ey
3.
Borings 1
through 8 located on Meadowglen Road and are not CONVERSE _ __ -_ MBS shown on this
drawing. CONSULTANTS = 7 =— -__= Approved By LTE MODFRN PASADENA
BLUEPRINT '
99934
Photo I: Street gutter and terrace drain outlet near 21U4U
Ambushers Street. A dark green algae growth has established
itself in the drain and along the concrete gutter.
Photo 1: i errace drain catch basin locted above 211 JU Ambushers
Street. Note crack running across concrete terrace drain.
95-31-281-01 page 1
Photo 3: Terrace drains on the rear yard slopes were poorly
maintained. Accumulated slope debris and weeds have blocked
the bottom of the channel causing the water to back-up and pond.
Photo 4: Overgrown trees and schrubs have fallen into the terrace
drains obstructing thier flow and limiting access along them.
95-31-281-01 Paae 2
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APPENDIX A
FIELD EXPLORATION
Field exploration included a site reconnaissance and subsurface drilling. During the
site reconnaissance, surface conditions were noted, and the locations of the test
borings were determined. Borings were approximately located using existing features
as a guide.
Test borings were advanced using a truck -mounted, eight -inch -diameter, hollow -stem
auger drilling rig equipped for soil sampling. Soils were continuously logged and
classified in the field by visual/manual examination, in accordance with the Unified Soil
Classification System. Field descriptions have been modified, where appropriate, to
reflect laboratory test results.
Ring samples of the subsurface soils were obtained at frequent intervals in the borings
using a drive sampler (2.4-inch inside diameter, 3-inch outside diameter) lined with
sample rings. The steel samplers were driven with a 140-pound hammer falling 30
inches. Blows required to drive the ring sampler one foot are also shown on the logs
in the "blows/foot" column. For the relatively undisturbed ring samples, soils were
retained in brass rings (2.4 inches in diameter, 1.0 inch in height) and carefully sealed
in waterproof plastic containers for shipment to the Converse geotechnical laboratory.
Bulk samples were also collected during the field exploration.
One of the two exploratory borings was converted to a monitoring well. A two -inch -
diameter, slotted polyvinyl chloride (PVC) pipe, with a three-foot blank section at the
top of the pipe, was installed. The pipe was surrounded with fine filter sand at the
slotted portion, and bentonite and concrete at the blank section. Locking wellheads
were provided at the well. The well was purged on the day installed and allowed to
recharge.
Logs of the borings are presented on Drawings A-1 and A-2, which also include
descriptions of the soils encountered, pertinent field data, and supplemental laboratory
results. Drawing A-3, "Exploration Log Key," describes the various symbols and
nomenclature shown on the logs.
9 5-31-281-01
Printed on Recycled Paper Converse Consultants West
Log of Boring No. BH-9
Date Drilled: 3/25/96 Logged by: DSS Checked by: MBS
Equipment: 8" Hollow Stern Auger Driving Weight and Drop: 140 pounds/30 inches
Ground Surface Elevation: 730 feet Depth to Water: none encountered
z
IL
0
H
z
CD
CLDJ SUMMARY
OF SUBSURFACE CONDITIONS This
log is part of the report prepared by Converse for this project and should
be read together with the report. This summary applies only at the location
of the boring and at the time of drilling. Subsurface conditions may
differ at other locations and may change at this location with the passage
of time. The data presented is a simplification of actual conditions encountered.
SAMPLES
o
LL
U)
O
m
r,
i
UJ
Ce
I
H
Z
z
r.
U
00.
p W
H
0
J
ccoo
2
inches of ASPHALT over 5 inches of SAND/GRAVEL BASE
ARTIFICIAL
FILL: CLAY (CL); silty, with fine sand, brown
mottled tan Encountered
concrete utility vault -moved to new 5
1 location and redrilled) 21
24 98 R ma
7-------_
ALLUVIU1v1:
CLAY (CL); silty, with fine sand, trace carbonate
filaments, dark brown to brown 10
26/ 20 107 10"
BEDROCK:
SILTSTONE AND SANDSTONE; siltstone 15
is
massive, weathered and oxidized, yellow brown 37
15 100 20
72/ 10"
26
93 End
of boring at 21 feet No
groundwater encountered i Monitoring
well installed Project
No. Drawing No. Converse
Consultants West J
95-31-281-01 A-1
Log of Boring No. BH-10
Date Drilled: 3/25/96 Logged by: DSS Checked by: MBS
Equipment: 8" Hollow Stem Auger
Ground Surface Elevation: 722 feet
Driving Weight and Drop: 140 pounds/30 inches
Depth to Water: none encuntered
SUMMARY OF SUBSURFACE CONDITIONS SAMPLES
This log is part of the report prepared by Converse for this project and H.\, 3
should be read together with the report. This summary applies only at the
0
O LLl H
U
H location of the boring and at the time of drilling. Subsurface conditions LL X
Z)
H
Z
2 may differ at other locations and may change at this location with the LJ
Y
M
3
F-
U) Zn4- aLL1
IL LD passage of time. The data presented is a simplification of actual conditions H J O H U 2
0 D-1 encountered.
U: m m E a: O
2 inches of ASPHALT over 5 inches of SAND/GRAVEL
BASE
ARTIFICIAL FILL: CLAY (CL); silty, with fine sand,
brown- -----------------
v J
Ai:1A CLAY (CL); silty, with fine sand, trace
5 carbonate filaments, brown
14/ 23 98
g
ma
10 44/
1011.
29 94
DROCK: INTERBEDDED SILTSTONE AND
SANDSTONE; laminated, weathered and oxidized, C yellow brown to brown
End of boring at 11 feet
No groundwater encountered
HoIe backfilled and asphalt patch placed on top
1:94
Project No. Drawing No.
Converse Consultants West
95-31-281-01 A-2
MAJOR DIVISIONS SYMBOLS TYPICAL NAMES
GW Well graded grovels, grovel-sond mrrures
Clean gravels with
p GRAVELS little or no tines
6 GP Poorly graded gravels, grwel-sand mixtures
o
More than half
o coarse fraction
nN Is larger then GM Sllty gravels, poorly graced gravel -scud silt mixturesJ
Oz No. 4 sieve Gravels With over
in C 12% tines
0= W GC Clayey gravels, poorly graded gravel -sand -clay mixtures
a Z
o a` SW Well graded sands, gravelly sands
LiV7 „ Clean sands with
y•
a- SANDS little or no fines
or SP Poorly graded sands, grve3ly sands
r' ca More then half
coarse fraction
is smaller than SM Silty sands, poorly graded :and -slit mixures
No. 4 sieve Sands with over
12% fines
C C,cM sands, poorly graced sand-c`.cy matures
MIL silts and very fine sands, rocs flour, silty or
4
clayey tine sands, or c:cyey silts with slight piasficetyclayey
a SILTS AND CLAYS
CL Inorganic clays of low to medium piastiay, grcveily
O clays, sandy clays• silty clays, lean c'cys
J N Liquid limit less than 50
a
Q z OIL Organic days and organic silty clays of low plcstic:y
Z_ O
C = an MH Inorganic silts, micaceous or diatomaceous fine, Sanay
0 u or silty sails• elastic silts
W v
Z
u- _
SILTS AND CLAYS
CH Inorganic clays of high plcs ;city, fc'. c:ays
0
Liquid limit greater than 50
CH organic clays of medium to hign pies c:y, organic 5.i's
x
HIGHLY ORGANIC SOILS Pt jd Peat and other highly organic soils
SAMPLE TYPE
DRIVE SAMPLE, 2.42-inch inside diameter
driven with 140-pound weight, 30-inch drop
ASTM D 3550-84)
BULK SAMPLE, loose cuttings from
exploration
TEST TYPE
Results shown in Appendix 8)
F-
CLASSIFICATION o
Plasticity pi
Grain Size Analysis ma
Sand Equivalent SE
Specific Gravity sg
Expansion Index El
Compaction Curve max
STRENGTH
Pocket Penetrometer p
Direct Shear ds
Unconfined Compression uc
Triaxial Compression tx
R-value R
CONSOLIDATION c
Collapse col
C+
EXPLORATION LOG KEY
CONVERSE a_
J
PraisCi No, Drawn No.
CONSULTANTS B`
a
95-31-281-01 A_3
APPENDIX B
LABORATORY TEST PROGRAM
95-31-281-01
gPrin(ed en Recycled Papa Converse ConsuFtants West
APPENDIX B
LABORATORY TEST PROGRAM
Laboratory tests were conducted in the Converse Consultants West (Converse)
geotechnical laboratory on representative soils samples for the purpose of evaluating
the physical properties and engineering characteristics of the sampled materials. A
summary of the various laboratory tests conducted is presented below.
In -Situ Moisture Content and Dry Density
Data obtained from these tests, performed on relatively undisturbed ring samples
obtained from the field, were used to aid in the clarification and correlation of the
earth materials and to provide qualitative information regarding soil strength and
compressibility. The percent of moisture as a function of dry weight, and the
encountered dry density in units of pounds -per -cubic -foot (pcf) are provided in the
right-hand columns on the exploration logs.
Grain -Size Distribution
Sieve analyses were performed on representative bulk samples to assist in soil
classification and to determine the distribution of soil particle sizes. The sieve
analyses were performed in general accordance with the ASTM D442-63 Standard
Test Method. Results are plotted on Drawing B-1, "Grain Size Distribution."
R-value
An R-value test was performed on a bulk soil sample for design of asphaltic pavement
over the subgrade soils. The test was performed by LaBelle -Marvin, and the test
results are enclosed at the end of this appendix.
Sample Storage
Samples presently stored in the Converse geotechnical laboratory will be discarded 30
days after the date of this report, unless this office receives a specific request to retain
samples for a longer period, at additional cost.
95-31-281-01
Printed on Recycled Paper Converse Consultants west
UNIFIED SOIL CLASSIFICATION
COBBLES
GRAVEL SAND
SILT OR CLEIY
COARSE I M4E COARSE MEMUM I FINE
U.S. SIM Sly IN INCHES U.S. STANDARD SIM No. HYDROMETER
a 9/4 1/2 8/0 4 10 20 40 40 240 Yoo
100
W
x
60
A
z 40
d
a
20
103 102
DEPTH'`
SYMBOL EXPLORATION ft m)
0 6H-9 5-7
BH-10 7-9
0
1 ft = 0.3048 m
20
M, ti
f
ioo
10 1 10-' 1 (-
2 1 0-3
GRAIN SIZE (mm)
DESCRIPTION
CLAY (CL), silty, some sand
CLAY (CL), silty
GRAIN SIZE DISTRIBUTION
CO SOUL TANTS V 1"I E CNVERSE No,n
MB 195-31-281-01
AN 1A.1pillelle Ala 1• •' 1 • TECHNOLOGYTDESIGN,GN
PROFESSIONAL PAVEMENT ENGINEERING
A CALIFORNIA CORPORATION
April 5, 1996
Mr, Hanna Kakish
Com,yyxsc Co-na-ahwlnn
222 E. Huntington Drive, Suite 211A
Monrovia_ California 91016-3500
Project No. 23506
Dear Mr. Kakish:
Enclosed herewith, please find the data sheets for the one (1)
sample of soil, identified as #95-31-281-01 1 Diamond Bar
Ambushers - BH-9 Bag #1 @ 5'-7', which was submitted to
our laboratory for R-Value determination.
The opportunity to be of service is sincerely appreciated and
should you have any questions, kindly call.
Very truly yours,
6t ven x .viarvin
ROE 30659
SRM:pg
Enclosures
2700 S. GRAND AVENUE* SANTA ANA, CA 92705 • (714) 546-3468 • FAX (714) 546-5841
R - VALUE DATA SHEET
95-21-281-01
Diamond Bar Ambush
PROJECT NUMBER 23506 BORING NUMBER: BH-9; Bag1 ; @ 5'-7'
SAMPLE DESCRIPTION: Light Brown Clayey Silt
Item SPECIMEN
a b c
Mold Number 4 5 6
Water added, grams 180 225 275
Initial Test Water, % 17.9 21.8 26.1
Compact Gage Pressure, psi 100 50 30
Exudation Pressure, psi 677 388 241
Height Sample, Inches 2.44 2.57 2.68
Gross Weight Mold, grams 3118 3142 3139
Tare Weight Mold, grams 2076 2076 2074
Sample Wet Weight, grams 1042 1066 1065
Expansion, Inches x 10exp-4 44 26 12
Stability 2,000 Ibs (160psi) 45 / 118 61 / 139 71 1 152
Turns Displacement 3.30 3.48 4.17
R-Value Uncorrected 21 10 3
R-Value Corrected 20 10 3
Dry Density, pcf 109.7 103.2 95.5
DESIGN CALCULATION DATA
Traffic Index Assumed: 4.0 4.0 4.0
G.E. by Stability 0.82 0.92 0.99
G.E. by Expansion 1.47 0.87 0.40
6 Examined & Checked: 4 / 2 / 96
Equilibrium R-Value by
EXUDATION
9a
Gf = 1.25 R.
REMARKS -
Ste arvi , •R 0659
The data above is based upon processing and testing sampl air #rom the
field. Test procedures in accordance with latest revisions to D ment of
Transportation, State of California, Materials & Research Test Method No. 301.
Lifflelle • Marvin
R-VALUE GRAPHICAL PRESENTATION
400
PROJECT NO.
A 350
BORING NO. - 7 1 300
DATE
w
200V)
V)
w
TRAFFIC INDEXAssomcd loo
c:)
R-VALUE BY EXUDATION 0
CL
m:
R-VALUE BY EXPANSION
C)
u
800 700 600 500 400 300 200 100
1:4
81
NEI rm
MMMO owl
no
um
MEMO-, Fi N CIM= Hm
580-1-
llVl
0 Emmm- wul
WIN 1 090 ff.. rim, I I mill
WEBB m-polill 69 gg 1019
1.0 2.0 3.0
COVER THICKNESS BY EXPANSION, FT.
100
90
80
70
60
U)
50 A4
40
30
20
P4
10
0
4.0
m mimmemomRENE
NORlmmm=.,.mm
min mlmg
vanimlronm
18-0 W) AL-0
0/10 MOISTURE AT FABRICATION
rmmmmromm
mm
Ml
SWIEL-
Imm umEE. MiMrs.
U—
INEHERF-151". 1 E!t
ME
Ionr
18,0 Z—. p .0
MOISTURE
R-VALUE vs. EXUD. FRES. T by EXUDATION
EXUD. T vs. EXP AN . T T by EXPANSION . REMARKS
G-r 4.
0 3.
0 Kim
1.
0 - m
i'
mildkik 0 Atmolnill PROFESSIONAL
PAVEMENT ENGINEERING