15040189-Backfill Testing❑
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Material Testing results for
Pool Backfill Testing at
10973 Wilkinson Ave.
Campbell, CA
Prepared for
NOECON
LM
Yale Bertolucci, CQE
Construction Quality Enterprises
P.O. Box 627, Lakeport, California 95453
Report Date
May 19, 2015
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i
Yale Bertolucci, COE
Construction Quality Enterprises
P.O. Box 627, Lakeport, California 95453
May 19, 2015
Noe Gonzalez
NOECON
P.O. Box 317
Alviso, California 95002
RE: Pool Backfill Testing, 10973 Wilkinson Ave., Campbell, CA
Dear Mr. Gonzalez,
Enclosed you will find for your review the report on the max density/opt moisture determination
and density test results, along with the invoice for the Pool Backfill Testing, 10973 Wilkinson
Ave., Campbell, CA
Please call me if you have any questions, wish to go over the data or require additional services..
I want to thank you for allowing us the opportunity of providing our services on your project. We
appreciate your business and hope we have provided you with service that meet or exceeded your
expectations.
Respectfully Submitted,
Yale Bertolucci
Owner/Senior Consultant
Toll Free: 877-813-9181
Fax: 866-685-5488
Yale Bertolucci, CQE
Construction Quality Enterprises
Client: NOECON Date: May 19, 2015
Project: Pool Backfill Testing Project No.: CQE 072-008
Project Location: 10973 Wilkinson Ave., Campbell, CA
Maximum Density/Optimum Moisture Determination
Sample Material Description Max Dry Density Optimum Moisture
#1 Dark Reddish Brown Sandy Silty Clay
W/Some Fine Gravel 122.0 13.3
#2 Dark Brown Sandy Silty Clay W/Fine to Coarse Gravel 122.6 11.7
#3 Brown Sandy Silty Clay W/Some Fine Gravel 117.1 12.9
Testing performed in accordance with ASTM D 1557-07 B
Yale Bertolucci
Owner/Senior Consultant
Yale Bertolucci, CQE
Construction Quality Enterprises
Client: NOECON Date: May 19, 2015
Project: Pool Backfill Testing Project No.: CQE 072-008
Project Location: 10973 Wilkinson Ave. Campbell, CA
Density Determination
Testing performed in accordance with ASTM D6938
V4&4 0 0,0001,
U
Yale Bertolucci
Owner/Senior Consultant
0
Percent
Comp. Curve
92 #1
98 #1
91 #3
92 #3
94 #2
93 #2
92 #2
97 #2
Test
Moist. Dry
Test
Date
Elev.
Test Location
Cont.
Dens.
2015
#1
5/13
-6.0'
9'S & 21'W of N W Corner of House
18.8
111.9
#2
5/13
-5.0'
6'S & 24'W of N W Corner of House
14.0
120.3
#3
5/14
-4.0'
21'S & 21'W of N W Corner of House
19.3
106.2
#4
5/14
-3.0'
6'S & 24'W of N W Corner of House
19.7
107.3
#5
5/15
-2.0'
21' S & 24'W of N W Corner of House
17.0
114.7
#6
5/15
-2.0'
6'S & 18'W of N W Corner of House
16.9
113.4
#7
5/15
-1.0'
10'S & 18'W of N W Corner of House
16.8
111.9
#8
5/15
-1.0'
24'S & 15'W of N W Corner of House
15.2
119.1
Testing performed in accordance with ASTM D6938
V4&4 0 0,0001,
U
Yale Bertolucci
Owner/Senior Consultant
0
Percent
Comp. Curve
92 #1
98 #1
91 #3
92 #3
94 #2
93 #2
92 #2
97 #2
/3'),
POOL DEMOLITION RECOMMENDATIONS
/ S 0 Y01g�
PROPOSED POOL DEMOLITION
10973 WILKINSON AVENUE
CUPERTINO, CALIFORNIA
Prepared for:
NOECON
Prepared by:
GeoEngineering Consultants
April 2015
�R inee
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GeoEngineering Consultants (GEC)
-4125 Blackford Avenue, -Suite 145
San Jose, CA 95117
Phone: 925-321-5550
Project No... P15.0159
April 28, 2015 .
Noe Gonzalez
NOECOlV
Subject: Proposed Pool Demolition
10973 Wilkinson Ave.
Cupertino, Ca
Pool Demolition and Backfill Recommendations
Dear Noe:
In accordance with .your: authorization,. GeoEngineering Consultants (GE(7) is providing this pool
demolition and backfill recommendation for the subject site.
-----
The. accompanying recommendation letter presents our findings and conclusions based on our
site visit. Our findings indicate that, from a geotechnical point of view, the proposed demolition
and backfill is feasible at the subject site provided the recommendations of this report are
carefully followed. and :are incorporated into the project plans:
Should you :have any questions_ relating to the contents of this letter report or should you require
additional information; please do not hesitate to contact our office at your convenience.
�� F ..
Sincerely yours,
GEC. No. G 66379
No. GE 2796
Exp. 6-30-20W
11 cM;-KZ
h ��
Kamran G 'assi, Ph.D., G.
Principal Geotechnical Engineer
Contents
1: 'INTRODUCTION...:............................:.................. 4:
...........:...:.......................:...
I.I. Purpose and Scope......................................:............................................................4
1.2. Project Description............ ........... :................................................ .. .................
5.
2. FINDINGS.................:...................................................................................:................5
2.1. Site Description .......... ...........:..::::.............. ................................. ................5
3. RECOMMENDATIONS .................... .... ...............5
......................................................... ...
3.1. General ......... ................. ..................................................................... ....:.........
.5
3.2. Demolition ........................
3.3. Backfill.....................:..:......................:::................................................ ..... ..6
APPENDIXA....................................:......................................................................................7
THE GRADING'SPECIFICATIONS.:::.:.................::...::..:....................::.....,:.........................::...:........8
GUIDE SPECIFICATIONS FOR ROCK UNDERFLOOR SLABS ................................................................ ...................................:.....................13
P15.0159 10973 Wilkinson Ave., Cupertino; Ca Apr. 28, 2015
1. INTRODUCTION
This -report summarizes our findings and :conclusions for use in consideration of :proposed pool
demolition:arid backfill at the above -referenced address, based on our site visit and review of the
City of Cupertino Guideline for Swimming: Pool Demolition.
1.1. Purpose and Scope
The purpose, of the work was to provide pool demolition and backfill recommendations at the site
located in Cupertino, California.
Our scope of service included the following::
a. Field reconnaissance by the Soil Engineer;
q. b. Preparation of this written: report.
This report has been prepared as a product of our service for the exclusive use of NOECON for the.
proposed pool demolition and backfill at the subject property. This report must not be used by other
parties or for other purposes without prior written authorization from GEC. No other warranty,
either expressed or implied,. is made.
Because of possible future changes in site conditions or the 'standards of practice for geotechnical
engineering, the findings and recommendations of this report may not be considered valid beyond
two years from the report. date, without review by GEC. In, addition, in the event- that any changes
in the nature or location of the proposed improvements are: planned, the conclusions and
recommendations of this report may not be considered valid unless such changes are reviewed, and
the conclusions and recommendations presented in this report are modified or verified in writing,
by this firm.
GEC Page 4
P15.0159 10973 Wilkinson Ave., Cupertino; Ca Apr. 28, 2015
-
1.2.. Proiect Description
Based on our discussions with you, we understood that the existing pool will be completely
demolished and will be backfilled. The existing -pool is up to. 6 feet deep and is roughly hour -glass
shape with: side length of about 35 feet. The minimum distance to the existing house footprint is
about 10 feet.
It is, assumed that: the area to be backfilled will not be used fora future building: pad or structure.
This report is not a Geotechnical Engineering Study. This -report should not be used for future
development iii the area of the proposed pool. backfill:
2. FINDINGS
- 2.1. Site Description
The roughly rectangular -shaped parcel -is located on a flat: site at 10973 Wilkinson Avenue : in
Cupertino and is one parcel. The site is bounded by Wilkinson Avenue to the east and Columbus
Avenue to the south and: other residences to the other directions. There is an existing two-story
wooden=frame _ house with an attached garage at the .site. The backyard: area has been landscaped.
Wooden fences separate the residence from the adjacent neighbors.
3: RECOMMENDATIONS
3,1. General .
From a geotechnical point of view, the proposed. pool demolition and backfill is feasible at the
subject site provided the recommendations presented in this letter are incorporated into the project
plans.
3.2. Demolition
The Contractor should remove the entire pool structure. All the decking and swimming pool
equipments,:pool structure bond beam, electric conduit, and gas lines should be removed.
GEC... Page 5
PB.0159 10973 Wilkinson Ave., Cupertino; Ca Apr. 28, 2015
3.3. Backfill
The grading requirements presented herein are an integral part of the grading specifications
presented in Appendix A of this report and should be considered as such.
Grading activities during the rainy season will be hampered by excessive moisture. Grading
activities may be performed during the rainy season, however, achieving proper compaction :may be
difficult due to excessive moisture; and delays may occur.
After demolition, the site may be brought to the desired finished .grades -by placing. engineered fill in
lifts not to exceed 8 inches in uncompacted thickness and compacted to a minimum relative
compaction of 90% at a moisture content of 2 to 5 percent above optimum as determined by ASTM
D 1557-91 Laboratory Test. Procedure. .
Should general import material be used to establish the proper grading for the proposed
development, the import material should be approved by the Soil Engineer before it is brought to
the site. General import material should preferably have. an expansion potential similar to or less
than the on site native soil. Selection of the import material is essential on rate of progress of the
project. The following criteria are suggested
a. Have an R -Value of not less than 25;
b. Have a Plasticity Index not higher than 16 (see Foundation section);
C. Not more than 15% passing: the No. 200 sieve; .
d. No rocks larger than 6 inches 'in maximum size;
GEC Page 6
APPENDIX A
The Grading Specifications
Guide Specifications for Rock Under Floor Slabs
THE GRADING SPECIFICATIONS
On
224332 CARNOUSTIE CT.
CUPERTINO, CALIFORNIA
1. General Description
1.1 These specifications have been prepared for the grading and site development of the subject
parking lot development. GEC, hereinafter described as the Soil Engineer, should be consulted
prior to any site work connected with site development to ensure compliance with these
specifications.
1.2 The Soil Engineer should be notified at least two working days prior to any site clearing or
grading operations on the property in order to observe the stripping of organically contaminated
material and to coordinate the work with the grading contractor in the field.
1.3 This item shall consist of all clearing or grubbing, preparation of land to be filled, filling of
the land, spreading, compaction and control of fill, and all subsidiary work necessary to complete
the grading of the filled areas to conform with the lines, grades, and slopes as shown on the
accepted plans. The Soil Engineer is not responsible for determining line, grade elevations, or slope
gradients. The property owner, or his representative, shall designate the person or organizations
who will be responsible for these items of work.
1.4 The contents of these specifications shall be integrated with the soil report of which they are
a part, therefore, they shall not be used as a self-contained document.
2. Tests
The standard test used to define maximum densities of all compaction work shall be the ASTM
D1557-91 Laboratory Test Procedure. All densities shall be expressed as a relative compaction in
terms of the maximum dry density obtained in the laboratory by the foregoing standard procedure.
3. Clearing, Grubbing, and Preparing Areas To Be Filled
3.1 If encountered, all vegetable matter, trees, root systems, shrubs, debris, and organic topsoil
shall be removed from all structural areas and areas to receive fill.
3.2 If encountered, any soil deemed soft or unsuitable by the Soil Engineer shall be removed.
Any existing debris or excessively wet soils shall be excavated and removed as required by the Soil
Engineer during grading.
3.3 All underground structures shall be removed from the site such as old foundations,
abandoned pipe lines, septic tanks, and leach fields.
3.4 The final stripped excavation shall be approved by the Soil Engineer during construction
and before further grading is started.
3.5 After the site has been cleared, stripped, excavated to the surface designated to receive fill,
and scarified, it shall be bladed until it is uniform and free from large clods. The native subgrade
soils shall be moisture conditioned and compacted to the requirements as specified in the grading
section of this report. Fill can then be placed to provide the desired finished grades. The contractor
shall obtain the Soil Engineer's approval of subgrade compaction before any fill is placed.
4. Materials
4.1 All fill material shall be approved by the Soil Engineer. The material shall be a soil or soil -
rock mixture which is free from organic matter or other deleterious substances. The fill material
shall not contain rocks or lumps over 6 inches in greatest dimension and not more than 15% larger
than 2-1/2 inches. Materials from the site below the stripping depth are suitable for use in fills
provided the above requirements are met.
4.2 Materials existing on the site are suitable for use as compacted engineered fill after the
removal of all debris and organic material. All fill soils shall be approved by the Soil Engineer in
the field.
4.3 Should import material be required, it must meet the specifications as delineated in the body
of this report.
5. Placine. Spreading, and Compacting Fill Material
5.1 - The fill materials shall be placed in uniform lifts of not more than 8 inches in uncompacted
thickness. Each layer shall be spread evenly and shall be thoroughly blade mixed during the
spreading to obtain uniformity of material in each layer. Before compaction begins, the fill shall be
brought to a water content that will permit proper compaction by either (a) aerating the material if it
is too wet, or (b) spraying the material with water if it is too dry.
5.2 After each layer has been placed, mixed, and spread evenly, either import material or native
material shall be compacted to a relative compaction designated for engineered fill.
5.3 Compaction shall be by footed rollers or other types of acceptable compacting rollers.
Rollers shall be of such design that they will be able to compact the fill to the specified density.
Rolling shall be accomplished while the fill material is within the specified moisture content range.
Rolling of each layer shall be continuous over its entire area and the roller shall make sufficient
trips to ensure that the required density has been obtained. No ponding or jetting shall be permitted.
5.4 Field density tests shall be made in each compacted layer by the Soil Engineer in
accordance with Laboratory Test Procedure ASTM D1556-64 or D2922-71. When footed rollers
are used for compaction, the density tests shall be taken in the compacted material below the
surface disturbed by the roller. When these tests indicate that the compaction requirements on any
layer of fill, or portion thereof, have not been met, the particular layer, or portion thereof, shall be
reworked until the compaction requirements have been met.
5.5 No soil shall be placed or compacted during periods of rain nor on ground which contains
free water. Soil which has been soaked and wetted by rain or any other cause shall not be
compacted until completely drained and until the moisture content is within the limits hereinbefore
described or approved by the Soil Engineer. Approval by the Soil Engineer shall be obtained prior
to continuing the grading operations.
6. Utility Trench Backfill
6.1 The utility trenches extending under concrete slabs -on -grade shall be backfilled with native
on-site soils or approved import materials and compacted to the requirements pertaining to the
adjacent soil. No ponding or jetting will be permitted.
6.2 Utility trenches extending under all pavement areas shall be backfilled with native or
approved import material and properly compacted to meet the requirements set forth by the City of
Cupertino.
6.3 Where any opening is made under or through the perimeter foundations for such items as
utility lines and trenches, the openings must be resealed so that they are watertight to prevent the
possible entrance of outside irrigation or rain water into the underneath portion of the structures.
7. Unusual Conditions
7.1 In the event that any unusual conditions not covered by the special provisions are
encountered during the grading operations, the Soil Engineer shall be immediately notified for
additional recommendations.
8. General Requirements
Dust Control
8.1 The contractor shall conduct all grading operations in such a manner as to preclude
windblown dirt and dust and related damage to neighboring properties. The means of dust control
shall be left to the discretion of the contractor and he shall assume liability for claims related to
windblown material.
t
GUIDE SPECIFICATIONS FOR ROCK UNDER FLOOR SLABS
Definition
Graded gravel or crushed rock for use under slabs -on -grade shall consist of a minimum thickness of
mineral aggregate placed in accordance with these specifications and in conformance with the
dimensions shown on the plans. The minimum thickness is specified in the accompanying report.
Material
The mineral aggregate shall consist of broken stone, crushed or uncrushed gravel, quarry waste, or a
combination thereof. The aggregate shall be free from deleterious substances. It shall be of such
quality that the absorption of water in a saturated dry condition does not exceed 3% of the oven dry
weight of the sample.
Gradation
The mineral aggregate shall be of such size that the percentage composition by dry weight, as
determined by laboratory sieves (U.S. Sieves) will conform to the following gradation:
Sieve Size Percentage Passing
3/4"
90-100
No. 4
25-40
No. 8
18-33
No. 200
0-3
Placing
Subgrade, upon which gravel or crushed rock is to be placed, shall be prepared as outlined in the
accompanying soil