2002-7041 G ({ / E NGINEERING SERVICES DEPARTMENT
it T'n mina Capital Improvement Projects
District Support Services
Field Operations
Sand Rep lenishment /Stormwater Compliance
Subdivision Engineering
Traffic Engineering
June 14, 2005
Attn: Wells Fargo Bank
1000 West San Marcos Blvd.
San Marcos, California 92078
RE: Scott Groeniger
425 Bridoon Terrace
APN 264 - 391 -19
Grading Permit 7041 -G
Final release of security
Permit 7041 -GI authorized earthwork, private drainage improvements, and erosion
control, all as necessary to build described project. The Field Inspector has approved
project. Therefore, release of the security deposit is merited.
The following Certificate of Deposit Account has been cancelled by the Financial
Services Manager and is hereby released for payment to the depositor.
Account # 3000708754 in the amount of $ 20,000.00.
The document originals are enclosed. Should you have any questions or concerns, please
contact Debra Geishart at (760) 633 -2779 or in writing, attention the Engineering
Department.
Sincelely,
D Geishart Jay Lean ach
Engineering Technician /�inance Manager
Subdivision Engineering Financial Services
CC: Jay Lembach, Finance Manager
Scott Groeniger
Debra Geishart
File
•.ilr 'IT , ,h,IIL1 l ncinna_,, 1 1!1h'im,l `� t l i�l i3O- i;.�.�- ',fii} ;i, recycled paper
I
n t ENGINEERING SERVICES DEPARTMENT
a i ;Zt j or
Capital Improvement Projects
District Support Services
Field Operations
Sand Rep lenishment /Stormwater Compliance
Subdivision Engineering
Traffic Engineering
June 9, 2005
Attn: Wells Fargo Bank, N.A.
Trade Services Division, Northern California
525 Market Street, 25` Floor
San Francisco, California 94105
RE: Scott Groeniger
425 Bridoon Terrace
APN 264 -391 -19
Grading Permit 7041 -G
Final release of security
Permit 7041 -GI authorized earthwork, storm drainage, site retaining wall, and erosion
control, all as necessary to build the described project. The Field Inspector has approved
this project. Therefore, a full release of the security deposited is merited.
Letter of Credit NZS434482, in the amount of $80,000.00, is hereby released in its
entirety. The document original is enclosed.
Should you have any questions or concerns, please contact Debra Geishart at (760) 633-
2779 or in writing, attention this Department.
Sincerely,
Debra Geishart / Jay embach
Engineering Technician Finance Manager
Subdivision Engineering Financial Services
CC: Jay Lembach, Finance Manager
Scott Groeniger
Debra Geishart
File
i l i oli jj - '(,OU kAX 60 {;i; -_'(:' �U5 1. ��UiC:.Ii 1�.i'�.1� ..u< iuitl5. <.a�ifurn 1.1 9' 1'.. .� � I)l� �r�l - %,� _. 'Ull recycled papa(
STORM DRAIN REPORT
' FOR
GROENIGER RESIDENCE
BRIDOON TERRACE
' ENCINITAS, CALIFORNIA
June 26, 2001
j vvJ
' Prepared By:
PARTNERS Planning and Engineering
9988 Hibert Street, 212
San Diego, CA 92131
' (619) 695 -3344
' DWG No. 7041 G
Andrew J. Kann. .E., RCE 5094
Registration Ex Tres 9 -30 -2001
1
' TABLE OF CONTENTS
' I. INTRODUCTION
A. Site and Project Description Page 1
B. Scope of work Page 1
' C. Methodology and Assumptions Page 2
II. RESULTS AND CONCLUSIONS Page 3
LIST OF FIGURES
I. Figure 1: Vicinity Map Page 4
CALCULATIONS
I. Hydrology Summary Page 5
' II. Hydraulic /Inlet Summary Page 6
' LIST OF APPENDICES
Appendix 1: Runoff Coefficients
' Appendix 2: Time of Concentration Urban Areas Overland Time of Flow
Appendix 3: Watersheds 100 -Year 6 -Hour Precipitation
Appendix 4: Watersheds 100 -Year 24 -Hour Precipitation
' Appendix 5: Intensity — Duration Design Chart
Appendix 6: Handbook of Hydraulics Tables 7 -4 and 7 -14
i
' INTRODUCTION
' Site and Project Description:
' The site consists of approximately 2.0 acres of Yeviousl graded lot at the end of
p
Bridoon Terrace in Encinitas, see Figure No. 1 (page 4) for location. The site currently
sheet flows to on -site brow ditches to two different locations and a portion of the lot
drains down the driveway. There is an existing stone lined ditch which drains one of the
browditches to the street. The second browditch drains to the property line with riprap at
' the terminus, per City of Encinitas drawing 9050 -G -18. The proposed development will
consist of an addition court yards, patios, and golf greens with adjacent landscaping. The
' runoff will be directed towards the existing outlet points of the on -site storm drain
system. All runoff will be discharged into an existing point of discharge.
Scope of Work:
1
This drainage report has been prepared to document the design and calculation for the
' drainage system associated with the site development of Groenuiger Residence on
Bridoon Terrace, in Encinitas, California. See Location Map on Page 4.
i
' Hydrology/Hydraulics Methodolo
Methodology:
This drainage system has been designed in general conformance with the County of San
Diego Drainage Design Manual. Drainage basins are less than one square mile;
' therefore, the Rational and Modified Rational Methods were utilized to calculate storm
runoff. The 100 -yr frequency storm has been used for runoff calculations.
' • The following are the runoff coefficient used, see Appendix 1, Runoff Coefficients —
Undeveloped/Developed Area.
' - Residential 0.55
' • Time of Concentration was calculated using Urban Areas Overland Time of Flow
Curves, See Appendix 2. A minimum time of concentration used was five minutes.
' • P6 determined by Isopuvials Charts for 100 -yr 24 & 6 hour Precipitation, See
Appendix 3 and 4.
' • Intensity was calculated using the Rainfall Intensity- Frequency Curves for
Y q Y
County of San Diego, see Appendix 5.
• Pipe sizing and flow routing was calculated b using M '
p g g y g arming s equation for channel
' flow. Calculations for pipes flowing partially full Tables 7 -4 and 7 -14 from
Handbook of Hydraulics, by Ernest F. Brater and Horace Williams King was used,
see Appendix 6.
2
RESULTS AND CONCLUSIONS
' The storm system is designed to convey the 100 -yr storm event.
' The pre - developed and post- developed basins are of the basic same area and there is no
diversion of flow from one basin to another.
No riprap will be required for the modification of the on -site system because the
proposed system utilizes the existing riprap or drains to the curb and gutter in the fronting
street.
i
I Project site.
1 aN RD. F� RD )
' LEUCAD/A BL W z % \ J,
- o
a Z 6 a LANE � y F
5 `
LNUNI TA N��'
' o S'9
BLVD
a
z
VICINITY MAP
NO SCALE
THOMAS BROS. PGS 1147 & 1148
L) �o
1
� N
R
Z O O
N N U N
' O O O O
00 00 00 00
V M M M M
O O O O
i of 7 V et
' A O O O O
00 M O�
,f O O M O
O O O O
1 A ..ti rr
o _ O O O
' O
y O Cl 0 0
' W
U
a O O O N
O O O O O O
N O� 00 O
U �C O C� O O
tn
H� O O O O O O O
O O O O O O O
C
�O C� O O Q\ O O
�o v1 vi
v
w ZU
v� O O O O O. O
C�
V O O O O O O
V� d ON ON N CP;
O
A a o 00 0o I
U = o 00 00 0
O O O O O O I
d ¢ m as m as c� Q
I
o
va I I
m
rn
t cc$
a
a
L y, 2 w 4. w
o 0 goo
a °
c 0orn�
V
W A
L Cd
V
� O �
xm�mxc7
' F
U
M d wl �o t-
ILI
a
F
O O C O O O
v
O C% O O
�I F •� � [� � � � Vl it
O O
O O O O O
F+ yam' O O - _; O O
(n v N N N -
W w 0 0 0 0 0 0
a C N V1
V'1 V') h N V1 V1
t� W1 00
t h O O O O O O
y V N N d N N M
a dam% 000000
A Q
tv Z QfnOA
N
� ,.PENo,x
RATIONAL METHOD RUNOFF COEFFICIENTS
LAND USE COEFFICIENT. C
Soil Group
A B C D
Residential:
Single Family .40 .45 .50 .55
' Multi -units .45 .50 .60 .70
Mobile homes .45 .50 .55 .65
' Rural (lots greater than 1/2 acre) .30 .35 .40 .45
' Commercial .70 .75 .80 .85
80% impervious
Industrial .80 .85 .90 .95
90% impervious
Sc San Dieao County Hydrology Manual
1
• AREAS OVERLAND
1 TIME D
FLOW
1 -
1 ~ T .r 1 11.! -CId6 il ls .5 = 1 ' � f i f
'
y _ • �Lf1 r. 1
•00 ' L
Us* Few
„>alla F or ►. 1 ' a r i _T' �J r �., ! 1 (
F Oistancet in Elcessl
Of 900 Fttt.
700 •• a....,. , ►+�J'�
. / + � �. 1._l'.•.• al • -
o
'
' >r . ;.:.; : ;�1� � ��;� �:w� �_ 'ter _ ,. :.. : .awe'. j.; �-•ia; ::•., - ),j.
i �tl. :L : a x'T� ��'r w 1'•.'rt•' '�i•� t.i��r"i„r' •.. -• +i
_� +�• Ir i'ati • j 1 - '• aL - �• rIl , --aT • -. '
JL
i . r te - �►�• -7 'tl�� rS._�_.: •• •_- •_'_.�-
1'•'I�j ' + ._ r 1' .T` ,� —��~ _�. '.117. •: ��.1 .!� T 7
Xn ' u_• . r ;(''';,• .y. _ •I ��� /:J , j is e,
rT
l i!'•aj: is. :j •� �. _ ` i.`. �. -. r,. a �ti. L L
�S; it 1 i i•I1 : • . � - .. ' . .: _ . � - , �•
1 100 • ! _ .. 1 t "'r r .+ ..
to AV
EXANt
GIVEt-4 '
• !_ENG7r} of Flow FT
SLOPE-
� q
1 CDEFFIC.IFNT of RvIjoFF C = .7p
� EJ�D OVP_ZL/aMD F,? DWTirnE_ = 15- ^AIAJ V
i
A f'
• AO
� t 111 I / 1 / 1t - 'r+v' — .Y 1 _ •
_� i` I • �i� 1 � 1 i
�C:D f
`tr r ✓- vim\ v�.,- _ '-
U7 x
Ln
0
S • J • / /j• �i"� •
z
� d _ •� I " Ir" .� t
' . 1 U..• L . / t
• , i �! ,yam. •• \. \ C i.'•f N M 1
M
_<
�-�• C ..t
/ L U z
Lr\
• u W c r -'
p i Z
' C'•'7 w i I V Y
�! !• U x u
J
w ..
Z t o o LA
tj
" G .� •�
O N V
• { U .
2 lL J �-
Q O O M W A G
• U
LL V7 0 V
O W O . J i
_ Xoa
u LL-
W
� n
� d Q
' 111 It -
xr
'
dir
rp
cm
r
ram.• . -��• u c � •
C o :
LL-
LIJ
ca
UP -
O
cn C=3
1 0
u • -
O W O
-
V L•\
' V C O
• W
O F U
1-+ O _
0 '
W"
N O O ' Ml
Lt- t 2
o w � r•,
�-
z < O 5 a
a o .� <
o w
u•O L L u
112
-._ ..
A4
u _
Ca
C O •a tl L
A t
N
' L v
tx
� •r ., a c
• a V - _
q C
CL TN '
N N+. �► C -.. .� C
' C CL �1 •e! y w L. O O �Ctl N • O !� O
u 4+ Y r + r � ut •r v "� a
�i L CL i•• 4-b ~ ■ L
C L Y b 'f. -G Y Y a te a ,. � �
a.1 OO L CV dO. _C 4
^^ 11"•C, 4 tl M^— pp C 8 r r
' c a L = U U L. • X tl .
4 y� S-4% L r- 4.0 L- tl -C YA 7
L r
90 6:3 ej O N O p .L •I C O L L N. 4
' N 4 . - G .0 •.- 4 . b U as tl f
C L M a N_ N V IO r. ~ �tl1 n•.IQ O
N
QJC M 7� 'r
o •I Q N +•f .• C n Y �. Y N }L r • 7 •
L .•- -C a. +--•
N 1.1 ••r � � O .-
N
t..1
6 -Hour Precipitation (inches)
wv
LU
ro
' N O•n0 NON .
r • b ,•1 Q p 1• ' • •�-� ..� ' . i I:..r •1' 11 , 1 !..
1t tl N . �• { 1 • i : L 1 . �: 11. 1 1 ( N 7C
9 F � M x L - c= .__ -_ •1• r 1 111
tti .-•. 0. Q ��� y
Vf
dw
1 _ •', t- N Y
( j92tpul) X.11SUa;ul
A.5
HANDBOOK OF HYDRAULICS
for the Solution of
Hydraulic Engineering Problems
Siisth Edition
Table 7 -14. Values of K' for Circular Channels in the Formula
I ' Q - K' 7 d9isls
D - depth of water d - diameter of channel
Of .00 .01 .02 .03 .04 .03 .06 .07 08 .09
.0 00007.0003i ooQ74 .00138 .00222 .00328 .00453 .00004 .0077
' .1 .oe7.ou u
s .ot .0107
o9 .0193 .022_3 .0257 .0_91 .0327 .0360
.2 .9406 .0448 .0192 .0337 .0385 .0634 .0680 .0738 .0793•.0849
.3 .0907 .0960 .1027 .1089 .1133 .1218 .1284 .1352 .1420 .1490
.4 .1561 .1633 .1703 .1779 .1854 .1929 .2005 .2082 .2100 .2238
.5 .232 .239 .247 .253 .263 .271 .279 .287 .295 .303
.6 .311 .319 .327 .335 .343 .330 .338 .366 .373 .380
.7 .388 .395 .402' .409 .416 .422 .429 .435 .441 .441
.8 .453 .438 AM .468 .473 .477 .481 .485 .468 .491
.9 .494 .496 .497 .498 .498 .498 .496 .4'14 .489 .483
1.0 .463
STEADY UNIFORM FLOW IN OPEN CHANNEL-z 7 - :')5
' Table 7-4. For Determining the Area a of the Cross `cction of a
Circular Conduit Flowing Part Fill
Let ' lepth of water _ D and C. - the tabulated value. Then a - /.'..d =.
diameter oi channel d
D i
.00 I .01 .02 .03 I .04 .OS .06 .07 .OS .09
d
I -
- .0 .0000I .0013 ..0037 .00691 .OI03I .014.1 .0192 .0242 .0-94 .0350
.1 .04091 .04 - 0 .03341 .Orm .04681 .0.391 .08.11 .0883 .0961 .1039
1119 .1199 .1 .13 .14491 .153 SI .1623 .1711 .1300 .1390
.3 .19821 .2074 :1671 .22 .23531 . -4301 .2346+ .2642 =39 .2336
4 2934 . 3032 3130 32 33 .342 .332 36: 3Tr 18
.5 .393 .403 .413 .423 •433 •443 •433 .462 .472 .493
.6 .492 .502 .5t2 .321 531 .540 .330 .539 .589 .575
.7 .581 •396 .505 .614 -!23 1 2 .640 .649 .687 .666
' .3 .674 .681 .689 .697 .104 2 .119 723 .732 .739
9 I .743 .750 .736 .761 .756 .771 I .: 75 .779 .182 .784
' Table 7 -3. For Determining the Hydraulic Radius r of the Cross
Section of a Circular Conduit Flowing Part Full
Let depth of +ester _ D and C. - the tabulated value. Then r - Cd.
diameter of cbaazel S
1
D .00 .01 I .02 .03 .04 O5 i .06 .07 .08 .09
d I
.0 .000 007 .013 .020 .025 .023 .039 .045 .031 .037
.1 .063 .070 .073 .081 .087 .093 .099 .104 .110 .113
.121 .126 .131 .136 .142 .147 .152 .157 .161 .166
.171 .176 .190 .183 .IS9 r .L93 .198 .202 .206 .2 10
.4 .214 -2 18 .222 .226 .229 ! •233 .mod r .40 ,.^•43 . - ^4;
.3 .25o .233 .256 .2SD I . = d2 ( .263 .268 270 .:73 .75
.a 2:S .-S0 .282 . 2 234
=96 .2S8 . 2 90 x 2 92 . 1 93 .295
T 296 '03 299 .3001 .301 .302 .302 .303 .304 .304
.S I .304 .304 .304 I .304 .304 ; .303 .303 .302 .301 .299
.29
4 .292 .239 ! .2S6 .283 .279 .274 .267
A ,(o
1
�C
TERRP� � C
I
o
1 `r�
DD
9'lQS SM
1
pt
' 15' HIDE FJ(SEMEN I i'DR SES
'RAIL F /CO
�•
-- - RECFEAF AI URFD_
yC X'. l f1 DEINGA fCn ✓EN MAF' NU; 12
r
Geotechnics
Incorporated
' Principals:
Anthony F. Belfast
September 5, 2002 Michael P. Imbriglio
' W. Lee Vanderhurst
Scott Groeniger Project No. 0634 - 001 -01
425 Bridoon Terrace Document No. 02 -0914
' Olivenhain, California 92024
Attention: Mr. Scott Groeniger
' SUBJECT: AS- GRADED GEOTECHNICAL REPORT
Mechanically Stabilized Earth Wall at 425 Bridoon Terrace
' Olivenhain Terrace, California
Dear Mr. Groeniger:
This report summarizes the results of the testing and observation services performed by Geotechnics
' Incorporated during construction of the Mechanically Stabilized Earth (MSE) wall for the Groeniger
residence located in Olivenhain, California. The wall construction was conducted by Geogrid
Retaining Wall Systems, Inc. Our geotechnical field services were performed between May 13, 2001
' and May 24, 2002.
' 1.0 PURPOSE AND SCOPE OF SERVICES
' This report and the associated geotechnical services were performed in accordance with the
provisions of our Proposal No. 02 -099 dated April 6, 2002 (Document No. 02- 0345). Our field
' personnel were provided for this project in order to test and observe earthwork construction
consisting of fill placement. We also observed construction of subsurface drainage systems, and
' geogrid placement in accordance with the design specifications. These observations and tests assisted
us in developing professional opinions regarding whether or not the geotechnical aspects of
earthwork construction were conducted in accordance with the project specifications and
' geotechnical recommendations. Our services did not include supervision or direction of the actual
work of the contractor, his employees, or agents. Our services did include the following.
• Observation of site re aration and subsequent fill placement during wall constriction f
P p 9 p g r o
confirmation that the work was being performed in accordance with the geotechnical
recommendations of our report dated May 7, 2002 (Project No. 0634 -001 -00, Document No.
' 02- 0452), and the project plans and specifications.
9245 Activity Rd., Ste. 103 • San Diego, California 92126
Phone (858) 536 -1000 • Fax (858) 536 -8311
SCOTT GROENIGER PROJECT NO. 0634 - 001 -01
' SEPTEMBER 5, 2002 DOCUMENT NO. 02 -0914
PAGE 2
' Performance of field and laboratory tests on the fill, to support our geotechnical
recommendations and conclusions.
• Observation of construction of subsurface drainage systems, and placement of geogrid.
t
Preparation of daily field reports summarizing the day's activity with regard to earthwork
P Y p g Y Y g
' and documenting hours spent in the field by our technicians.
' Preparation of this report summarizing site preparation, field and laboratory test results, and
the fill placement operations.
2.0 SITE DESCRIPTION
1
The MSE wall is approximately 200 feet in length and varies from approximately 6 to 11 feet high.
' The ground surface behind the MSE wall is relatively gently sloped. The ground surface in front of
the wall is generally flat. A recently constructed single family house is located within approximately
' 50 feet from the toe of the MSE wall.
' 3.0 BACKFILLING OPERATIONS
3.1 Fill Soils
Fill placed within the reinforced zone of the MSE wall was produced by mixing the 4 -inch
' minus portion of the excavated soil /rock from the back -cut excavation with approximately
15% by weight of decomposed granite. The resultant soil is classified as clayey gravel with
' sand (Unified Soil Classification: GC). Crushed rock was also used within the reinforced
soil zone in some areas directly behind the block facing of the MSE wall. The maximum
' density and optimum moisture content of the clayey gravel was determined in the laboratory
using ASTM method D1557 as a guideline. The clayey gravel had a very low to low
' Expansion Index.
Geotechnics Incorporated
SCOTT GROENIGER PROJECT NO. 0634 - 001 -01
' SEPTEMBER 5, 2002 DOCUMENT NO. 02 -0914
PAGE 3
3.2 Fill Placement
' Backfilling of the wall was performed with loaders. The soil was spread in 8 to 12 -inch thick
lifts and compacted. The equipment used for the compaction operations included a vibratory
' drum roller and hand operated compactors. In -place moisture and density tests were made in
general accordance with ASTM D 2922 and D 3017 (Nuclear Gauge Methods). The results
' of the density tests are tabulated in the figures of Appendix C. The locations and elevations
indicated for the tests are based on field survey stakes and estimates from the grading plan
' topography, and should only be considered rough estimates. The estimated locations and
elevations should not be used for preparing cross sections showing test locations, or in any
case, for the purpose of after - the -fact evaluating of the sequence of fill placement.
3.3 Geogrid Placement
Stratagrid 200 was used was used to reinforce the soil behind the block facing of the MSE
' wall. Geogrid lengths varied form approximately 5 to 8 feet depending on the wall height,
with a vertical grid spacing of approximately 2 feet. The grid was secured to the facing
' blocks with pins. The geogrid placement was completed in general accordance with the
designers specifications.
' 3.4 Subsurface Drainage System
' The subsurface drainage system for the MSE wall consisted of a 4 -foot wide geo- composite
panel drain spaced on 10 -foot centers placed on the back -cut. In addition, a "burrito" drain
' consisting of a perforated pipe surrounded in crushed rock and filter fabric was constructed
behind the toe of the wall.
4.0 GEOTECHNICAL EVALUATION AND RECOMMENDATIONS
' In general, it is our opinion that wall construction and compaction of the soil at this site were
performed in general accordance with the intent of the project geotechnical recommendations. Based
upon our observations and testing, it is our professional opinion that the fill was placed in substantial
accordance with the compaction criteria of 90 percent of the maximum density. The conclusions
' Geotechnics Incorporated
' SCOTT GROENIGER PROJECT NO. 0634 - 001 -01
SEPTEMBER 5, 2002 DOCUMENT NO. 02 -0914
PAGE 4
' contained herein are based on our observations and testing performed between May 13, 2001 and
May 24, 2002.
' 5.0 LIMITATIONS
' Our services were performed using the degree of care and skill ordinarily exercised, under similar
' circumstances, by reputable soils engineers and geologists practicing in this or similar localities. No
warranty, expressed or implied, is made as to the conclusions and professional opinions included in
this report. The samples taken and used for testing, the observations made, and the in -place field
' testing performed are believed representative of the project. However, soil and geologic conditions
can vary significantly between tested or observed locations.
The findings of this report are valid as of the present date. However, changes in the conditions of a
' property can occur with the passage of time, whether they are due to natural processes or the works
of man on this or adjacent properties. In addition, changes in applicable or appropriate standards
' may occur, whether they result from legislation or the broadening of knowledge. Accordingly, the
findings of this report may be invalidated wholly or partially by changes outside our control.
' Therefore, this report is subject to review and should not be relied upon after a period of three years.
GEOTECHNICS INCORPORATED
' Maurice Amendolagine, P.E. 62962 Anthony F. Belfast, P.E. 40333
Project Engineer Principal
' Distribution: (4) Addressee
2 ,�,OFESS /U
�O � p;1nEN�
, -y �2
' No. C6 ,962 m m
d
EXP. �
ylr
O \ �"
C A�
' Geotechnics Incorporated
' APPENDIX A
' REFERENCES
American Society for Testing and Materials (2000). Annual Book of ASTM Standards, Section 4,
' Construction, Volume 04.08 Soil and Rock (I); Volume 04.09 Soil and Rock (H);
Geosynthetics, ASTM, West Conshohocken, PA, 1624 p., 1228 p.
Geotechnics Incorporated . Geotechnical Recommendations, Additions to 425 Bridoon
IP ( 2001)
Terrace, Olivenhain, California, Project No. 0634 - 001 -00, Document No. 1 -0073, dated
March 2.
' Geotechnics Incorporated (2002). Proposal for Geotechnical Services, Geogrid Wall Construction
at 425 Bridoon Terrace, Olivenhain, California, Proposal No. 02 -099, Document No. 02-
0345, dated April 6.
Geotechnics Incorporated (2002). Geogrid Wall Recommendations, Geogrid Wall Construction at
' 425 Bridoon Terrace, Olivenhain, California, Project No. 0634 - 001 -01, Document No. 02-
0452, dated May 8.
Geogrid Retaining Wall Systems, Inc. 2002. Groeni er Residence Job #515 Wall and Drainage
1� g Y ( ) g e g
Composite Recommendations, May 9.
Geotechnics Incorporated
1
' APPENDIX B
' LABORATORY TESTING
Selected samples of the soils encountered were tested using test methods of the American Society for
' Testing and Materials, or other generally accepted standards. Laboratory testing was conducted in a
manner consistent with that level of care and skill ordinarily exercised by members of the profession
' currently practicing under similar conditions and in same locality. No warranty, expressed or
implied, is made as to the correctness or serviceability of the test results or the conclusions derived
' from these tests. Where a specific laboratory test method has been referenced, such as ASTM,
Caltrans, or AASHTO, the reference applies only to the specified laboratory test method and not to
associated referenced test method(s) or practices, and the test method referenced has been used only
' as a guidance document for the general performance of the test and not as a "Test Standard." A
brief description of the tests performed follows.
' Maximum Density Optimum Moisture The maximum density and optimum moisture for
' representative soil samples were determined by using test method ASTM D1557 as a guideline. The
test results are summarized in Figure B -1.
1
1
1
' Geotechnics Incorporated
1
MAXIMUM DENSITY /OPTIMUM MOISTURE CONTENT
' (ASTM D 1557)
MAXIMUM OPTIMUM
' SAMPLE SAMPLE DESCRIPTION DRY DENSITY MOISTURE
(PCF) N
' Max #1 Clayey Gravel with Sand (GC) 142 5
' Project No. 634 - 001 -01
=G e o t e c h n 1 c s Document No. 02 -0914
I n c o r p o r a t e d LABORATORY TEST RESULTS
' FIGURE B -1
' FIELD TEST RESULTS
The results of the field density tests taken during site grading are presented in the following figure.
The elevations and locations of field tests were determined by hand level and pacing relative to field
staking done by others. The elevations and locations should not be assumed to be more accurate than
' implied by the method of measurement.
' The precision of the field density test and the maximum dry density test is not exact and variations
should be expected. For example, the American Society for Testing and Materials has recently
' researched the precision of ASTM Method No. DI 557 and found the accuracy of the maximum dry
density to be plus or minus 4 percent of the mean value and the optimum moisture content to be
' accurate to plus or minus 15 percent of the mean value; the Society specifically states the "acceptable
range of test results expressed as a percent of mean value" is the range stated above. In effect, an
indicated relative compaction of 90 percent has an acceptable range of 86.6 to 92.8 percent based on
' the maximum dry density determination. The precision of the field density test ASTM D1556 has
not yet been determined by the American Society for Testing and Materials; however, it must be
' recognized that it also is subject to variations in accuracy.
t The following abbreviations were used in the figures of Appendix C:
' RW = Retaining Wall
1
r
r =G e o t e c h n i C s DENSITY TEST RESULTS Project No, 0634 - 001 -01 Inc orporated Groeniger Residence Document No. 02 -0914
FIGURE C -1
r Test Test Elevation Location/ Soil Max. Dry Moisture Dry Relative Required Retest
No. Date IN Station Type Density Content Density Compaction Compaction Number
Ipcfl [ %] [ pct] 1 %] N
r RW -1 5/13/02 587.5 East 1F 142.5 7.7 131.4 92 90
RW -2 5/14/02 587.5 East 1 C 138.5 5.9 127.5 92 90
RW -3 5/14/02 588 West 11 146.8 7.1 132.3 90 90
' RW -4 5/15/02 588 West 11 146.8 6.7 131.6 90 90
RW -5 5/16/02 590.8 West 1K 149.8 7.0 134.4 90 90
RW -6 5/16/02 591 East 1K 149.8 6.4 134.8 90 90
' RW -7 5/16/02 589.5 West 1K 149.8 7.7 134.3 90 90
RW -8 5/17/02 591 West 1K 149.8 7.8 136.3 91 90
RW -9 5/17/02 592 West 1K 149.8 5.9 135.0 90 90
RW -10 5/17/02 592 East 1K 149.8 4.5 134.5 90 90
' RW -11 5/20/02 594 West 1 K 149.8 5.4 135.9 91 90
RW -12 5/20/02 594 East 1 K 149.8 6.1 134.6 90 90
RW -13 5/23/02 595 East 11 146.8 6.0 134.5 92 90
r RW -14 5/23/02 596 East 1J 148.3 5.0 136.3 92 90
RW -15 5/23/02 595 West 11 146.8 6.6 134.0 91 90
RW -16 5/24/02 598 East 1C 138.5 9.3 129.1 93 90
RW -17 5/24/02 600 West 1C 138.5 10.0 126.7 91 90
r
1
r
1
r
1
1
1
1
r
Geotechnics
Incorporated
' Principals:
Anthony F. Belfast
Michael P. Imbriglio
' W. Lee Vanderhurst
' GEOTECHNICAL RECOMMENDATIONS
ADDITIONS TO 425 BRIDOON TERRACE
' OLIVENHAIN, CALIFORNIA
' prepared for
' Mr. Scott Groeniger
425 Bridoon Terrace
Olivenhain, California 92024
1
by
' GEOTECHNICS INCORPORATED
Project No. 0634 - 001 -00
Document No. 1 -0073
MAY
ENaiN�i`
' March 2, 2001 CITY0FLf0NrrA,
1
9245 Activity Rd., Ste. 103 • San Diego, California 92126
' Phone (858) 536 -1000 • Fax (858) 536 -8311
1
Geotechnic s
Incorporated
' Principals:
Anthony R Belfast
Michael P. Imbriglio
' March 2, 2001 W. Lee Vanderhurst
' Mr. Scott Groeniger Project No. 0634- 001 -00
425 Bridoon Terrace Document No. 1 -0073
Olivenhain, California 92024
' SUBJECT: GEOTECHNICAL RECOMMENDATIONS
Additions to 425 Bridoon Terrace
' Olivenhain, California
Gentlemen:
' In accordance with Y our authorization, we have prepared this report presenting our recommendations
for conducting earthwork construction at the site and regarding the geotechnical aspects of
foundation design. This report presents the results of our laboratory testing, engineering analysis,
conclusions, and recommendations for the proposed improvements.
' We appreciate this opportunity to provide professional services. If you have any questions or
comments regarding this report or the services provided, please do not hesitate to contact us.
' Respectfully submitted,
t GEOTECHNICS INCORPORATED
Anthony F. Belfast
Principal
' DR/WLV /MA/AFB
Distribution: (2) Addressee
(2) Mr. Jeff Briggs, Ralph Stone & Associates
(2) Mr. Larry Dutton, Partners Planning & Engineering
9245 Activity Rd., Ste. 103 • San Diego, California 92126
' Phone (858) 536 -1000 • Fax (858) 536 -8311
GEOTECHNICAL RECOMMENDATIONS
' ADDITIONS TO 425 BRIDOON TERRACE
OLIVENHAIN, CALIFORNIA
' TABLE OF CONTENTS
' 1.0 INTRODUCTION ............................ ..............................1
2.0 SCOPE OF SERVICES ...................... ............................... 1
' 3.0 SITE DESCRIPTION ......................... ..............................2
4.0 PROPOSED IMPROVEMENTS ............... ............................... 2
5.0 GEOLOGY AND SUBSURFACE CONDITIONS . ............................... 3
6.0 GEOLOGIC HAZARDS AND SEISMICITY ..... ............................... 3
6.1 Seismicity ............................ ..............................4
' 6.2 Ground Rupture ....................... ..............................4
6.3 Liquefaction and Dynamic Settlement ..... ............................... 4
6.4 Landslides and Lateral Spreads ........... ............................... 5
' 6.5 Tsunamis, Seiches, Earthquake Induced Flooding ........................... 5
7.0 CONCLUSIONS ............................. ..............................6
8.0 RECOMMENDATIONS ...................... ..............................7
8.1 Plan Review ....................7
....... ................... ..........
8.2 Grading and Excavation Observation . 7
8 .3 Earthwork ............................ ..............................7
8.3.1 Site Preparation ............... ......................... 8
......
8.3.2 Excavation Characteristics . 8
8.3.3 Bulking and Shrinking Estimates .. ...............................
' 8.3.4 Temporary Excavations :::::::: ::::::::::::::::::::::::::::::. 9
9
8.3.5 Removals 10
8.3.6 Keyways and Benching ........ ............................... 10
8.3.7 Subsurface Drainage Systems ... ............................... 11
8.3.8 Expansive Soil ....... ............................... 11
8.3.9 Cut/Fill Transitions ........... ............................... 11
' 8.3.10 Structural Fill Materials ....... ............................... 12
8.3.11 Fill Compaction ............. ............................... 12
8.4 Slope Stability ....................... ............................... 13
' 8.5 Slope Protection ....................... .............................14
8.6 Preliminary Foundation Recommendations ............................... 14
' 8.7 Moisture Protection for On -Grade Slabs .. ............................... 16
8.8 Earth Retaining Structures 17
8.9 Exterior Slabs ......................... .............................18
8.10 Reactive Soils ...................... ............................... 18
Geotechnics Incorporated
1
' GEOTECHNICAL RECOMMENDATIONS
ADDITIONS TO 425 BRIDOON TERRACE
OLIVENHAIN, CALIFORNIA
t TABLE OF CONTENTS (Continued)
' 9.0 LIMITATIONS OF INVESTIGATION ......... ............................... 18
' ILLUSTRATIONS
' Site Location Map .::::::::::::::::::::::: ::::::::::::::::::::::::::::::: Figure
Fault Location Map Figure 2
Transition Details ......................... ............................... Figure 3
' Wall Drain Detail ......................... ............................... Figure 4
Regional Seismicity ....................... ............................... Table 1
' APPENDICES
REFERENCES ....................... ............................... Appendix A
LABORATORY TESTING .............. ............................... Appendix B
1
1
1
Geotechnics Incorporated
1
GEOTECHNICAL RECOMMENDATIONS
' ADDITIONS TO 425 BRIDOON TERRACE
OLIVENHAIN, CALIFORNIA
' 1.0 INTRODUCTION
This report presents the results of our limited geotechnical evaluation of the residence located at 425
' Bridoon Terrace in Olivenhain, California. The purpose ofthe evaluation was to provide preliminary
geotechnical recommendations for the proposed additions to the existing residential structure. This
report presents the results of our laboratory testing, engineering analysis, conclusions regarding the
feasibility of the proposed improvements, and recommendations regarding the geotechnical aspects
' of the project.
' 2.0 SCOPE OF SERVICES
' The scope of services provided during this investigation was consistent with that outlined in our
Proposal No. 0 -313. As indicated in the proposal, the subsurface conditions were exposed by the
' excavations being conducted for the drainage system. The recommendations presented in this report
are based on our experience with sites underlain by similar conditions, and the following services.
' Review of pertinent geologic and s topographic ra hic ma available literature related to the general
P g g P g P P, g
' geologic and seismic conditions in the area, and evaluation of stereoscopic aerial
photographs. The pertinent references are listed in Appendix A.
' 0 Site reconnaissance to observe existing conditions and collect a sample of the surficial soil.
• Laboratory analysis of a sample retrieved from the site. The analysis consisted of expansion
' index and soluble sulfate content testing. The test results are presented in Appendix B.
• Evaluation of the site's seismicity and potential geologic hazards.
• Engineering analyses including evaluation of bearing capacity, frictional resistance, and
lateral earth pressures.
' Preparation of this report presenting the results of the laboratory testing, conclusions
regarding the suitability of the site for its proposed improvements, and geotechnical
' recommendations regarding earthwork construction, foundation design, slab design, and
retaining wall design.
Geotechnics incorporated
GROENIGER RESIDENCE PROJECT NO. 0634- 001 -00
MARCH 2. 2001 DOCUMENT NO. 1 -0073
PAGE NO. 2
3.0 SITE DESCRIPTION
' The site is a single - family residence located at 425 Bridoon Terrace in Olivenhain, California (Site
Location Map, Figure 1). The irregular- shaped property encompasses roughly 1' /z acres that is
' situated along the top of a gently sloping ridge. The ground surface at the site generally slopes to
the west - southwest at inclinations of less than 5:1 (horizontal to vertical), with the exception of a
relatively flat area at the east side of the site where a pad has been graded. The elevation at the site
is roughly 600 feet above sea level, with approximately 50 feet of relief from the bottom of the
driveway to the northern site boundary.
The pad appears to have been constructed by excavating a portion of the slope to the north and east,
and placing fill in the southwestern portion of the pad area. A two -story house is situated in the
central portion of the pad. A long driveway leads from the street to the residence. Much of the
remainder of site is un- improved, although excavations were being made along the north side of the
driveway and north side of the western portion of the site. The excavations were reportedly for a
' subsurface drainage system.
' 4.0 PROPOSED IMPROVEMENTS
The proposed improvements include the construction of a single -story garage/boat house and a sports
court along the east side of the site, a pool house south of the existing structure, a pool west of the
' structure, and a patio with gazebo between the pool and pool house. The new buildings are
anticipated to be built with wood frame construction, supported on conventional shallow
' foundations.
' The northern part of the existing pad area will be extended to the north by excavating the existing
natural slope, and constructing either a 12 foot high cantilever or Mechanically Stabilized Earth
(MSE) wall. Some fill may be placed in the new patio area and in the general area of the sports
court. Fill depths are anticipated to be less than 10 feet. Constructed slopes are anticipated to be less
than 10 feet high.
Geotechnics Incorporated
-- _
IF
r
,tiY t
i 1
s . .
f 4 tM:
t \ t
5
r
a �
t— 1
r k r+ t
+tr Y%NT•r � f \!
rA I ' t1
y u z
SITE
v
,
I
..1 ......_..
N ,� � , Flo
ai. iii bLlt., m .S � I -
l.� 4
C
t e. � SrR141N�. ( 7i s!h
it c�
1
SMH[-
PyT I rc s
cm
Lttt `.
PARK
z v ti �� LAr �+ UL34tle.t.�lt F a •J -w' .: " 'edr�'..:. � } i a»,..+ I .a',
� se
I FF
CAN l t l� i' �t;A� o:.' �t�, `+, I, x"71;•
fl _
—
i
'1
,A
t,
' Reference: Thomas Brothers Guide 2000. 0.5 Miles
G e o t e c h n i c s Project No. 0634 - 001 -00
Inco rporated
SITE LOCATION MAP Document No. 1 -0073
FIGURE 1
Rev. 6/99
GROENIGER RESIDENCE PROJECT NO. 0634- 001 -00
t MARCH 2. 2001 DOCUMENT NO. 1 -0073
PAGE NO. 3
' 5.0 GEOLOGY AND SUBSURFACE CONDITIONS
' The subject site is located within the Peninsular Ranges Geomorphic Province of California. This
province, which stretches from the Los Angeles basin to the tip of Baja California, is characterized
' as a series of northwest trending mountain ranges separated by subparallel fault zones, and a coastal
plain of subdued landforms. The mountain ranges are underlain primarily by Mesozoic metamorphic
' rocks that were intruded by plutonic rocks of the southern California batholith, while the coastal
plain is underlain by subsequently deposited marine and nonmarine sedimentary formations.
' The site is situated in the transition zone between the rugged mountain ranges and the coastal plain.
Specifically, the site is underlain by metavolcanic rocks known as the Santiago Peak Volcanics,
' which is partially buried by a relatively thin mantle of topsoil. The metavolcanic rock is Jurrassic
in age. At the site, it consists of mildly metamorphosed andesitic volcanic rock that is massive and
' hard, with extensive fracturing. The fractures are typically less pronounced with depth. Exposures
of fresh rock are generally dark gray to bluish gray. Iron -oxide staining discolors the older surfaces
' to reddish brown hues. The rock decomposes to silt with sand to fat clay that is generally olive green
to reddish brown, and exhibits medium to high plasticity. The topsoil consists generally of moderate
brown, sandy lean clay. The clay is generally soft to firm, and is considered compressible. The clay
exhibits medium plasticity, and medium expansion potential.
' Some fill exists at the site at the southwestern portion of the existing pad. The fill appears to be up
to approximately 8 feet thick and composed primarily of materials that had been excavated from the
' site. Documentation regarding the placement of the fill was not provided to us.
' Based on the proposed grading, significant groundwater is not anticipated to be encountered at the
site. Subsurface water conditions may fluctuate during periods of significant rainfall or due to
' changes in on -site or nearby irrigation.
' 6.0 GEOLOGIC HAZARDS AND SEISMICITY
' The subject site is not located within an area previously known for significant geologic hazards
including active faulting, liquefiable soils, or collapsible soils. Potential geologic hazards at the site
' are as follows:
' Geotechnics Incorporated
GROENIGER RESIDENCE PROJECT NO. 0634- 001 -00
' MARCH 2. 2001 DOCUMENT NO. 1 -0073
PAGE NO. 4
' 6.1 Seismicity
' Seismic hazards at the site are anticipated to be caused primarily by ground shaking during
seismic events on adjacent active faults. Figure 2, the Fault Location Map, shows the general
' location of the site in relation to active and potentially active faults in southern California and
northern Baja California. The nearest known active fault is the Rose Canyon fault zone,
located approximately 8 miles (12 kilometers) west of the site. The Rose Canyon fault zone
' is a Type B fault per the 1997 Uniform Building Code. The nearest known Type A fault is
the Elsinore fault zone located approximately 25 miles northeast of the subject site.
1
6.2 Ground Rupture
Ground surface rupture is the result of movement on an active fault reaching the surface.
' The Fault Location Map, Figure 2, shows the relationship between known active faults in the
region and the site. There are no known active faults underlying the site or projecting toward
' the site. Evidence of active faulting was not found at the site. The site is not located in an
Alquist - Priolo Earthquake Fault Zone. In our opinion, there is little probability of surface
rupture due to faulting beneath the site; however, lurching and ground cracking are a
possibility as a result of a significant seismic event on a regional active fault.
' 6.3 Liquefaction and Dynamic Settlement
' Liquefaction is a process in which soil grains in a saturated deposit lose contact due to
earthquakes or other sources of ground shaking. The soil deposit temporarily behaves as a
' viscous fluid; pore pressures rise, and the strength of the deposit is greatly diminished.
Liquefaction is often accompanied by sand boils, lateral spread, and post - liquefaction
' settlement as the pore pressures dissipate. Liquefiable soils typically consist of cohesionless
sands and silts that are loose to medium dense, and saturated. Clayey soil deposits do not
liquefy because the soil skeleton is not supported by grain to grain contact, and is therefore
' not subject to densification by shaking. To liquefy, soils must be subjected to a ground
shaking of sufficient magnitude and duration.
1
The site is underlain primarily by hard rock. The topsoil exhibits a medium to high plasticity
' indicating a significant clay content. Additionally, loose sediments will be removed and
Geotechnics Incorporated
0 10 20 30 40 50 60
M,gOR CUCAMONGA FAULT SCALE
LOS 0%ES
34'
1p
G et
`\ ♦ kSi \ DIOa o ti E
\t MF R
pr �
�y l yid �t0 ;
Y C SAN JUAN 0�
�p ! ` ° Sc ` • CAPISTRANO F'l
`F 9 000 '0 tiF
o %
\ °off Fr OCEANS �� % �•. �`.
O
\` '0 0 y • E ONDIDO tr0
ti
33'
1110y� � 1 Op k �.
y+" SAN �� EL CENTRO • `•
yy DIEG • t �'' _
'" y � � USA MEXICALI • �G!
Fc MEXI l F, �
a 0 • TIJUANA ♦♦ q o A
7y,J 9o G �♦ ,P'Ft
� •
d
i e v `♦
32' ct0d
• ENSENADA `F
!e N
�o
ACV, 9LANCA PAUL
ZONE
Modified from Anderson, Rockwell, Agnew, 1989
= G e o t e c h n i c s Project No. 0634 - 001 -00
Incorporated
FAULT LOCATION MAP Document No. 1 -0073
FIGURE 2
' \Drafting \CorelDraw \Fault Rev. 10/00
0 M V-
0 ~ o W
W W< 0 O J
F- ^
DLO 0 O N 0 0 0 0 0 0 Q
H Q' O r M L.6 CV � c i O M Z F-
' M
W U) C O C
Oi N O 0)
Y z E
v 0) L) U
Q U + + + + + + + + t C L
W W W W W W W W W W ca a W
p `Q } 0 0 0 0 0 0 0 0 0 W O
M M M c) cM M cM cM C•M O cu m
' W 2 Q cM cM co M C•M M M M cM 00 L
U) =p M CT) O
U
N c- U
Q Q U >, O O
' W W M N M M M M M M M E N ui
a W W W W W W W W W � E o
co o o co 0 0 U) o o X c a .. ca
I - O r- O OU M O (Q C2
' W a L6 on cli C4* �- co Y C
LL C O (� N
s -� I m L U
C +�
C L c LL
�
' p H p -' c c c C) C N
V W O� 7 11') L1 LC) O N O m ) a) H U)
00 - Cn OC O —�
C a o_ M O
Q O
M W cu
Y U) -C
H p Y U O C N
p a)
U) C V D to
O 'D O
� Z Q O 00 00 ti LO N CD CD O (D O. 2 .. "O
0 0 0 0 0 0 O� c X
a - w (U C6
W m °) a) E
p m p co >
W W g '` % cu
�
Z U O = c
' Cn Y- N m LO N M �t IN f- M M - E p -a C N
U) 0 u co M (CO 0
p c - to _a •N . L y
' Y O
O 3
m m M m O O O S
N .�
0) E 2 cu cu • .�
' w m Cn a) rn N - c w W .�? : S,
c O= s E= c c c a) cn � °) 0
O� cu O C c V U
c -° Q a) m m a) m E o E m a =a a v
O O ch C -0 M a) CT N C ice+ Y�
Q O Z a) c in W 0) C CU cQ N �. C U 3
LL j m W FL c O N >, 0 -0 cn ,& u Y
O -
' ri 0) cu E r�
0) X L
O CU (� a c m_�` V
3° o cu = Y c J 2 o
Z 0 C m W M n� t c
N cn <t LO CO
GROENIGER RESIDENCE PROJECT NO. 0634- 001 -00
' MARCH 2. 2001 DOCUMENT NO. 1 -0073
PAGE NO. 5
' replaced with compacted fill during earthwork construction. In our opinion, the potential for
liquefaction and associated dynamic settlement to occur at the site following development
' is remote.
' 6.4 Landslides and Lateral Spreads
Evidence of existing landslides at the site was not found. In our opinion, the potential for
' slope instabilities at the site following development is low.
6.5 Tsunamis, Seiches, Earthquake Induced Flooding
' The project site is located at elevations above 100 feet above mean sea level. Documented
accounts, or predicted run -up heights for coastal southern California using 100 -year and
' 500 -year events, do not exceed 15 feet above mean sea level. Accordingly, the potential for
flooding at the site due to tsunami is remote.
' Based on the site's elevation above the drainage courses in the area, the potential for flooding
at the site caused by a seiche appears remote.
1
1
Geotechnics Incorporated
GROENIGER RESIDENCE PROJECT NO. 0631- 001 -00
' MARCH 2, 2001 DOCUMENT NO. 1 -0073
PAGE NO. 6
7.0 CONCLUSIONS
' Based on the results of this evaluation, it is our opinion that the proposed improvements are feasible
from a geotechnical standpoint provided the following recommendations and appropriate
' construction practices are followed. No geotechnical conditions were encountered that would
preclude the proposed construction. Geotechnical design and construction considerations include
the following:
• There are no known active faults underlying the project site. Potential seismic hazards at the
' site will likely be associated with ground shaking from an event along nearby active faults,
such as the Rose Canyon fault zone located approximately 8 miles west of the site.
' In general, the metavolcanic rock underlying the site is considered suitable for the support
of structural loads. The topsoil, however, is considered compressible and should be removed
' prior to the placement of settlement sensitive improvements. The condition of the existing
fill at the site should be evaluated during grading to remove any loose soil that may exist.
' Excavations at the site should generally be achievable using standard excavation equipment
in good - working order with experienced operators; however, some rock breaking and/or
blasting may be required where excavations greater than roughly 3 feet deep are anticipated
' in the metavolcanic rock.
• Significant groundwater is not anticipated to be encountered in the proposed excavations.
' Relatively minor groundwater and surface water may be encountered around periods of
precipitation.
' In general, the materials at the site are considered suitable for reuse in compacted fills with
the exception of material required within the reinforced zone of the MSE wall. The soils in
the reinforced zone should consist of free draining sand and gravel. Some of the on -site
' materials may exhibit a high potential for expansion and over -sized clasts of hard rock may
be generated by the planned excavations. The highly expansive materials should not be
placed within 5 feet of finish grade. Any over -sized material will require special handling
' to be incorporated in the proposed fill. Any deleterious materials or debris encountered are
not considered suitable for reuse at the site.
Geotechnics Incorporated
GROENIGER RESIDENCE PROJECT NO. 0634-001-00
' MARCH 2. 2001 DOCUMENT NO. 1 -0073
PAGE NO. 7
' 8.0 RECOMMENDATIONS
' The remainder of this report presents recommendations for earthwork and construction of the
proposed improvements, as well as preliminary geotechnical recommendations for the design of
' foundations for single- family structures. These recommendations are based on empirical and
analytical methods typical of the standard -of- practice in southern California. If these
' recommendations appear not to address a specific feature of the project, please contact our office for
additions or revisions to the recommendations.
' 8.1 Plan Review
' It is recommended that foundation and grading plans be reviewed by Geotechnics
Incorporated prior to plan finalization. Significant changes in the development from the
' preliminary plans used for this investigation may require additional geotechnical evaluation.
' 8.2 Grading and Excavation Observation
Foundation excavations and site grading should be observed by Geotechnics Incorporated.
' During grading, Geotechnics Incorporated should provide observation and testing services
continuously. Such observations are considered essential to identify field conditions that
' differ from those anticipated by the preliminary investigation, to adjust designs to actual field
conditions, and to determine that the grading is accomplished in general accordance with the
' recommendations of this report. Recommendations presented in this report are contingent
upon Geotechnics Incorporated performing such services. Our personnel should perform
' sufficient testing of fill during grading to support our professional opinion as to compliance
with compaction recommendations.
t 8.3 Earthwork
' Earthwork for the proposed development is anticipated to include remedial grading of
existing compressible and unsuitable soils; excavation ofpad areas, slopes, temporary trench
' excavations for underground utilities; and placement of fill and backfill. Grading and
earthwork should be conducted in accordance with the Grading Ordinance of the City of
Geotechnics Incorporated
GROENIGER RESIDENCE PROJECT NO. 0634- 001 -00
' MARCH 2. 2001 DOCUMENT NO. 1 -0073
PAGE NO. 8
' Encinitas, the California Building Code (CBC), and the recommendations of this report. The
following recommendations are provided regarding specific aspects of the proposed
' earthwork construction.
8.3.1 Site Preparation
t General site preparation should include the removal of unsuitable and deleterious
materials or other improvements from areas that will be subjected to structural or fill
loads. Clearing and grubbing should consist of the removal of vegetation including
' brush, grass, weeds, woods, stumps, trees, tree roots, and otherwise deleterious
materials from areas to be graded. Clearing and grubbing should extend to the
' grading limits. The debris generated by the clearing and grubbing should be legally
disposed off -site.
' All existin g buildings, s, structures, foundations, utilities (above and below ground),
' cisterns, wells, tunnels, and any other man-made improvements within the grading
limits, that are not to be saved for future use, should be demolished and hauled off-
' site. Subsurface improvements or obstructions that extend below grade should be
excavated and hauled off site. Demolition of pipelines may consist of capping or
rerouting at the project perimeter, and removal within the project perimeter. If
' appropriate, abandoned pipelines may be filled with grout or slurry cement as
recommended by, and under the observation of, the geotechnical consultant. Wells,
' cisterns, seepage pits and shafts should be filled and capped in accordance with the
governing authorities. Trees or man -made improvements to be saved should be
' protected from damage by the contractor.
' 8.3.2 Excavation Characteristics
In general, excavations should be achievable using standard heavy earthmoving
equipment operated by experienced personnel. However, some rock breaking and/or
blasting may be desired where fresher metavolcanic rock is encountered. Based on
' the excavation observed for the drainage system, excavations in metavolcanic rock
greater than a few feet deep are anticipated to be generally non - rippable. Where
' Geotechnics Incorporated
GROENIGER RESIDENCE PROJECT NO. 0634- 001 -00
MARCH 2. 2001 DOCUMENT NO. 1 -0073
PAGE NO. 9
' blasting or rock breaking is conducted, the material should be reduced to no greater
than 12 inches in largest dimension if it is to be incorporated into the fills.
' Excavations in the metavolcanic rock may generate oversized materials that will
require special handling for reuse in structural fills. Significant quantities of this
material, resulting in the construction of "rock fills ", is not anticipated.
8.3.3 Bulking and Shrinking Estimates
' Excavation of the on site materials for re -use in compacted fills will result in some
bulking of the formational materials, and shrinking of the loose surficial soil. The
' metavolcanic rock may bulk between 10 and 20 percent. The topsoil may shrink
between 5 and 15 percent.
' 8.3.4 Temporary Excavations
P rY
Temporary excavations, such as for the removal of unsuitable soils and for utility
trenches, may exceed 5 feet in depth. All excavations should be laid back or shored
and should conform with Cal -OSHA guidelines. Workmen should be protected from
falling rocks in accordance with Cal -OSHA requirements.
Temporary slopes up to 20 feet in height and in competent rock should be laid back
' no steeper than' /2:1 (horizontal to vertical). Temporary slopes in soil should be laid
back no steeper than 1:1 (horizontal to vertical). Temporary excavations that
' encounter seepage or other potentially adverse conditions should be evaluated by the
geotechnical consultant on a case -by -case basis during grading. Remedial measures
' may include shoring, or reducing the inclination of the temporary slope.
For temporary excavations that will be shored, but not braced with tie -backs or struts,
we recommend using a triangular pressure distribution for calculating earth pressures,
based on the soil conditions. In general, shoring design in sandy soil may be based
' on an equivalent fluid pressure of 35 lbs /ft', plus any groundwater pressures
encountered in the excavation, and any surcharge loads resulting from loads placed
' above the excavation and within a 1:1 plane extending upward from the base of the
' Geotechnics Incorporated
GROENIGER RESIDENCE PROJECT NO. 0634- 001 -00
MARCH 2. 2001 DOCUMENT NO. 1 -0073
PAGE NO. 10
' excavation. In clayey soil, an equivalent fluid pressure of 55 lbs /ft', or more, may be
recommended. Should surcharge loads be anticipated, or braced shoring be used,
' Geotechnics Incorporated should be contacted for additional design parameters.
' 8.3.5 Removals
Unsuitable materials typically include topsoil, undocumented fill soils, weathered
' formational materials, or other soil subject to settlement under increased loads,
wetting, or bio- degradation. The removal of unsuitable materials should be
' conducted under the observation of the geotechnical consultant to evaluate the
competency of the exposed materials for support of structural loads. The excavation
' of unsuitable materials should be conducted in a way that minimizes the disturbance
of competent materials. Excavated material that is free of deleterious or oversize
' materials may be re -used in compacted fills upon evaluation by the geotechnical
consultant. Areas where removals are completed should be scarified approximately
' 8 inches deep, brought to slightly above optimum moisture content, and compacted
in accordance with the recommendations contained herein.
' 8.3.6 Keyways and Benching
' Keyways should be excavated at the base of fill slopes under the observation of the
geotechnical consultant. The width and bottom elevation of each keyway should be
' provided by the geotechnical consultant based on an evaluation of the site conditions.
The minimum key width is 15 feet. The entire key should be excavated into
' competent rock and tilted towards the slope at an inclination of 2 percent or more.
The exposed keyway should be scarified to a depth of approximately 8 inches,
' brought to slightly above optimum moisture content, and compacted prior to placing
fill.
Where fill is to be placed on surfaces inclined steeper than 5:1 (horizontal to
vertical), benches should be excavated to provide a relatively level surface for fill
' placement. The benches should extend through any loose, unsuitable materials to
expose competent material as evaluated by the geotechnical consultant. The bench
' width should generally be adequate to expose 3 to 5 feet of competent material in the
' Geotechnics incorporated
GROENIGER RESIDENCE PROJECT NO. 0634- 001 -00
' MARCH 2. 2001 DOCUMENT NO. 1 -0073
PAGE NO. I I
' vertical wall of the bench. The exposed bench bottoms should be scarified to a depth
of approximately 8 inches, brought to slightly above optimum moisture content, and
' compacted prior to placing fill. Excavated material that is free of deleterious or
oversize materials may be re -used in compacted fills upon evaluation by the
' geotechnical consultant.
' 8.3.7 Subsurface Drainage Systems
Based on our understanding that the proposed fills will be less than 10 feet deep, and
that some subsurface drainage presently exists at the site, the installation of
additional subdrains in not anticipated. Recommendations regarding drainage
' systems associated with retaining walls are presented in Section 8.8.
' 8.3.8 Expansive Soil
To reduce the potential for heave of finish grade, we recommend that soil exhibiting
an Expansion Index greater than 90, based on UBC Test Method 18 -2 or ASTM
D4829, be removed from the upper 5 feet of finish grade of structural fills. Testing
' of the subgrade soils should be conducted during grading to evaluate the expansive
nature of the subgrade soils.
8.3.9 Cut/Fill Transitions
Depending on the location of the proposed buildings, and the extent of remedial
' grading, the proposed structures may straddle materials with varying settlement
potentials. These conditions generally occur along or near transitions from fill to
' formational materials. In order to reduce the potential for adverse settlement, we
recommend that the cut or formational portion of the pad be over - excavated and
' replaced with compacted fill. The depth of the over - excavation should be 3 feet
below foundation -bottom grade, or to a depth of H/2 where H is the greatest depth
of fill beneath the structure, whichever is greater (Figure 3). Pad grade should be re-
' established with fill compacted as recommended in the following section.
1
Geotechnics Incorporated
1
CASE 1.0
- --__ _ FILL
RIP 12 INCHES, 3 FEET
' WATER, COMPACT (MAXIMUM) FORMATION
' CASE 2.0
FILL
OVER - EXCAVATE TRANSITION
TO A DEPTH OF H/2 (3 FEET MINIMUM) H > 3 FEET FORMATION
CASE 3.0
H >3FEET
2 %SLOPE —► ''- -_
FILL
OVER - EXCAVATE TRANSITION
TO A DEPTH OF H/2 (3 FEET MINIMUM)
FORMATION
G e o t e c h n i c s Project No. 0634 - 001 -00
In corporated
TRANSITION DETAILS Document No. 1 -0078
FIGURE 3
' \Drafting \CorelDraw \Overex Rev. 1/00
GROENIGER RESIDENCE PROJECT NO. 0634- 001 -00
' MARCH 2. 2001 DOCUMENT NO. 1 -0073
PAGE NO. 12
' 8.3.10 Structural Fill Materials
' Materials being considered for use in compacted fill should be evaluated by the
geotechnical consultant prior to placement, but may include materials excavated from
' cuts, materials excavated during remedial grading (removals), or imported materials.
In general, fill soils should be free of deleterious or "oversized" material which is
' defined as material greater than 12 inches in its maximum dimension.
To facilitate the excavation of footings and utility trenches, it is generally
recommended that material greater than 6 inches in dimension not be placed within
3 feet of finish pad grade, or within 2 feet of the deepest utility, whichever is deepest.
' It should be noted that the material used to backfill trenches should generally not
exceed 6 inches in maximum dimension. Accordingly, materials generated from
' trench excavations in fills including larger material will require screening prior to use
as backfill. The depth of pad over - excavation should be based in part on the
' anticipated excavations (footings, landscape, pools), but typically no less than 3 feet.
' Imported fill sources, if needed, should be observed prior to hauling onto the site to
determine the suitability for use. Representative samples of imported materials and
on site soils should be tested by the geotechnical consultant in order to evaluate their
' appropriate engineering properties for the planned use.
' During grading operations, soil types other than those analyzed in the geotechnical
reports may be encountered by the contractor. The geotechnical consultant should
' be notified to evaluate the suitability of these soils for use as fill and as finish grade
soils.
' 8.3.11 Fill Compaction
' All fill and backfill should be accomplished at slightly over optimum moisture
conditions and using equipment that is capable of producing a uniformly compacted
' product. Fill materials at less than optimum moisture content should have water
added and the fill mixed to result in material that is uniformly slightly above
1 optimum moisture content. Fill materials that are too wet should be aerated or mixed
' Geotechnics Incorporated
GROENIGER RESIDENCE PROJECT NO. 0634- 001 -00
' MARCH 2. 2001 DOCUMENT NO. 1 -0073
PAGE NO. 13
' with dryer material to achieve uniformly moisture - conditioned soil. The fill and
backfill should be placed in horizontal lifts at a thickness appropriate for the
' equipment spreading, mixing, and compacting the material, but generally should not
exceed 8 inches in loose thickness. The minimum recommended relative compaction
' for fill and backfill is 90 percent of maximum density based on guidelines of ASTM
D1557. The slope faces should be compacted to the recommended 90 percent
relative compaction, either by rolling with a sheepsfoot roller or with other suitable
heavy equipment, or by overfilling the slope and cutting back to design grade.
Sufficient observation and testing should be performed by the geotechnical
' consultant so that an opinion can be rendered as to the compaction achieved. Rocks
or hard clumps greater than 6 inches in dimension should not be used in trench
' backfill, backfill for reinforced earth walls, or retaining wall backfill.
' 8.4 Slope Stability
' Based on our present understanding, slopes constructed at inclinations of 2:1 (horizontal to
vertical) or flatter for heights up to 10 feet will generally meet or exceed a factor -of- safety
' of 1.5, provided the slopes are constructed as recommended herein. The construction of the
slopes should be observed by Geotechnics Incorporated continuously to evaluate the exposed
conditions for conformance with anticipated conditions. Should unanticipated planes or
' zones of weakness exist, additional recommendations will be provided.
' Fill slopes may be constructed at inclinations up to 1'/2:1, provided that slopes steeper than
2:1 are reinforced with geofabric such as Mirafi HP70 or similar. The geofabric
specification should be based on the specific slope application. The installation of the
geofabric should be conducted in accordance with manufacturer's recommendations.
' Typically, geofabric reinforcement should be placed at vertical intervals of no more than 24
inches, and each layer should extend in horizontally from the face of the slope a minimum
' of 6 feet. However, this may vary with specific slope applications.
All slopes are subject to some creep, whether the slopes are natural or man -made. Slope
' creep is the very slow, down -slope movement of the near surface soil along the slope face.
The degree and depth of the movement is influenced by soil type and the moisture
' conditions. This movement is typical in slopes and is not considered a hazard. However,
' Geotechnics Incorporated
GROENIGER RESIDENCE PROJECT NO. 0634- 001 -00
MARCH 2. 2001 DOCUMENT NO. 1 -0073
PAGE NO. 14
' it may affect structures built on or near the slope face. We recommend that structures not
be located within 10 feet of the top of the slopes, unless specific evaluation of the structure's
' foundation is conducted by the geotechnical consultant.
' 8.5 Slope Protection
Although the anticipated slopes are anticipated to be stable with regard to deep- seated failure,
they may be susceptible to erosion and spalling. Surficial slope stability may be enhanced
by providing proper site drainage. The site should be graded so that water from the
' surrounding areas is not able to flow over the top of the slope. Diversion structures should
be provided where necessary. Surface runoff should be confined to gunite -lined swales or
' other appropriate devices to reduce the potential for erosion. It is recommended that slopes
be planted with vegetation that will increase their stability. Ice plant is generally not
recommended. We recommend that vegetation include woody plants, along with ground
cover. All plants should be adapted for growth in semi -arid climates with little or no
' irrigation. A landscape architect should be consulted in order to develop a specific planting
palate suitable for slope stabilization. Site irrigation should be limited to the minimum
' necessary to sustain landscaping plants.
8.6 Preliminary Foundation Recommendations
Based on this investigation, conventional spread foundation types are suitable for the
' proposed improvements. The following recommendations are based on the conditions
encountered during this investigation and are considered preliminary. Design -level
' recommendations will be provided based on the as- graded conditions at each location a new
structure is planned.
The following preliminary recommendations are generally consistent with methods typically
used in southern California. Other alternatives may be available. The following foundation
recommendations are minimum criteria based on geotechnical concerns. They should not be
considered a structural design, nor should they be considered to preclude more restrictive
' criteria by governing agencies or the structural engineer. The design of the foundation
system should be performed by the project structural engineer.
Geotechnics Incorporated
1
GROENIGER RESIDENCE PROJECT NO. 0634- 001 -00
' MARCH 2. 2001 DOCUMENT NO. 1 -0073
PAGE NO. 15
' The following design parameters assume that the foundations for the proposed buildings will
consist of shallow spread footings bearing entirely on compacted fill and that the materials
' will have a medium expansion potential.
' Allowable Bearing: 3,000 psf (allow a one -third increase for short-term
wind or seismic loads)
' Minimum Footing Width: 12 inches for strip footings
24 inches for isolated footings
' Minimum Footing Depth: 24 inches below lowest adjacent soil grade or finish
floor, whichever is deepest.
' Minimum Reinforcement: Two No. 4 bars at both top and bottom in continuous
footings.
' On -Grade Slabs: At least 5 inches in thickness, reinforced No. 3 bars
on 18 -inch centers, each way in the middle of the slab.
' Foundations constructed near the tops of slopes should be deepened as necessary so that the
minimum distance from the outside bottom edge of the footing and the slope face is 8 feet
or more. It should be recognized that the outer few feet of all slopes are susceptible to
' gradual down -slope movements due to slope creep. This will affect hardscape such as
concrete slabs. We recommend that settlement sensitive hardscape not be constructed within
' 5 feet of the top of slopes.
' Lateral loads may be resisted by friction and by the passive resistance of the supporting soils.
A coefficient of friction of 0.3 may be used between the bottom of footings and the
' compacted fill or formational material. The passive resistance of those materials may be
assumed to be equal to the pressure developed by a fluid with a density of 300 pcf. A one-
' third increase in the passive values may be used for wind or seismic loads. The passive
resistance of the materials may be combined with the frictional resistance without reduction
' in evaluating the total lateral resistance.
' Geotechnics Incorporated
GROENIGER RESIDENCE PROJECT NO. 0634- 001 -00
' MARCH 2. 2001 DOCUMENT NO. 1 -0073
PAGE NO. 16
' The following CBC seismic parameters may be used for design of the proposed buildings:
' Seismic Zone Factor, Z: 0.4
Seismic Source Type: B
' Soil Profile Type: S
' Seismic Coefficients, C,: 0.40N„
C v : 0.40N
' Near- Source Factors, N,,: 1.0
N v : 1.0
8.7 Moisture Protection for On -Grade Slabs
Concrete slabs constructed on soil ultimately cause the moisture content to rise in the
' underlying soil. This results from continued capillary rise and the termination of normal
evapotranspiration. Because normal concrete is permeable, the moisture will eventually
' penetrate the slab unless some protection is provided. To decrease the likelihood of
problems related to damp slabs, suitable moisture protection measures should be used where
' moisture sensitive floor coverings or other factors warrant. A commonly used moisture
protection consists of about 2 inches of clean sand covered by "10 -mil visqueen" plastic
sheeting. In addition, 2 inches of sand are placed over the plastic to decrease concrete curing
' problems associated with placing concrete directly on an impermeable membrane. It has
been our experience that such systems will transmit from approximately 6 to 12 pounds of
' moisture per 1,000 square feet per day. This may be excessive for some applications,
particularly for wood floors, vinyl tile, or sheet vinyl. If more moisture protection is needed,
' the project architect should be contacted to assist in the design of the under -slab system. The
project architect should review the moisture requirements of the proposed flooring system
' and incorporate an appropriate level of moisture protection as part of the floor covering
design.
' Geotechnics Incorporated
GROENIGER RESIDENCE PROJECT NO. 0634- 001 -00
' MARCH 2. 2001 DOCUMENT NO. 1 -0073
PAGE NO. 17
' 8.8 Earth Retaining Structures
' For cantilever retaining walls, where the backfill is level or nearly level, an active earth
pressure approximated by an equivalent fluid pressure of 351bs /ft maybe used. Where the
' earth slopes upwards at 2:1, an equivalent fluid pressure of 50 Ibs /ft may be used. The
active pressure should be used for walls free to yield at the top at least 0.2 percent of the wall
height. For walls restrained so that such movement is not permitted, an equivalent fluid
pressure of 55 lbs /ft should be used, based on at -rest soil conditions with level backfill. In
addition to the recommended earth pressure, walls adjacent to vehicular traffic should be
r designed to resist a uniform lateral pressure of 1001bs /ft , acting as a result of an assumed
3001bs /ft surcharge behind the wall. The above pressures assume no hydrostatic pressures.
' If these are applicable, they will increase the lateral pressures on the wall and we should be
contacted for additional recommendations. Walls should contain an adequate subdrain to
' reduce hydrostatic forces. Wall drain details are given in Figure 4, Wall Drain Details.
' Backfilling retaining walls with expansive soils can increase lateral pressures well beyond
the active or at -rest pressures indicated above. We recommend that retaining walls be
' backfilled with free draining soil with less than 5 percent passing the No. 200 sieve (by
weight), and having an Expansion Index of 20 or less. The backfill area should include the
zone defined by a 1:1 sloping plane, back from the base of the wall. Retaining wall backfill
' should be compacted to at least 90 percent relative compaction, based on Modified Proctor
density. Backfill should not be placed until walls have achieved adequate structural strength.
Heavy compaction equipment which could cause distress to walls should not be used.
' If an MSE (Mechanically Stabilized Earth) wall is used, the spacing and the length of the
reinforcement should be designed by a qualified engineer based on the characteristics of the
soil used in the backfill. The lateral earth pressures are as presented herein assuming that the
backfill consists of free draining soil with less than 5 percent passing the No. 200 sieve (by
' weight), and has an Expansion Index of 20 or less. Recommendations regarding MSE wall
drains should be provided once the design of the wall is known.
Geotechnics Incorporated
DAMP - PROOFING OR WATER-
' PROOFING AS REQUIRED
' ROCK AND FABRIC 12
ALTERNATIVE
' . (jOMPAGTED- " .
BAGKFILL -
°0 12 -INCH
MINIMUM
' MINUS 3/4 -INCH CRUSHED ROCK
ENVELOPED IN FILTER FABRIC ° WEEP -HOLE
(MIRAFI 140NL, SUPAC 4NP, OR oo ALTERNATIVE
APPROVED SIMILAR)
4 -INCH DIAM. PVC
' PERFORATED PIPE
DAMP - PROOFING OR WATER-
' PROOFING AS REQUIRED
1 • ,;' ;,; .;, 12•• ' , _' x'
GEOCOMPOSITE
PANEL DRAIN ' : PANEL DRAIN
: ALTERNATIVE
' GOMPACTED.
BACKFILL-
1 CU. FT. PER LINEAR FOOT OF WEEP -HOLE
' MINUS 3/4 -INCH CRUSHED = = ALTERNATIVE
ROCK ENVELOPED IN ..:
FILTER FABRIC
/ 77 77 /i
4 -INCH DIAM. PVC
PERFORATED PIPE
NOTES
' 1) Perforated pipe should outlet through a solid pipe to a free gravity outfall. Perforated pipe and outlet
pipe should have a fall of at least 1 %.
2) As an alternative to the perforated pipe and outlet, weep -holes may be constructed. Weep -holes
' should be at least 2 inches in diameter, spaced no greater than 8 feet, and be located just above
grade at the bottom of wall.
3) Filter fabric should consist of Mirafi 140N, Supac 5NP, Amoco 4599, or similar approved fabric.
' Filter fabric should be overlapped at least 6- inches.
4) Geocomposite panel drain should consist of Miradrain 6000, J -DRain 400, Supac DS -15, or
' approved similar product.
5) Drain installation should be observed by the geotechnical consultant prior to backfilling.
e o t e c h n i c s Project No. 0634 - 001 -00
In corporated
WALL DRAIN DETAILS Document No. 1 -0078
FIGURE 4
' \Drafting\Core1Draw \Wa11drn Rev. 6/99
GROENIGER RESIDENCE PROJECT NO. 0634 - 001 -00
MARCH 2. 2001 DOCUMENT NO. 1 -0073
PAGE NO. 18
' 8.9 Exterior Slabs
' As a minimal recommendation, exterior slabs should be at least 5 inches thick and should
be reinforced with at least No. 3 rebar spaced 24 inches on center each way, or with 6 -inch
' x 6 -inch, W2.9 x W2.9 welded wire fabric placed mid - height. Crack control joints should
be used on all exterior slabs, with a maximum spacing of 5 -foot centers each way for
' sidewalks and 10 -foot centers each way for slabs. In order to reduce heaving of concrete,
sidewalks should be constructed over 2 feet of compacted fill or formational materials with
an Expansion Index of 20 or less. Differential movement between sidewalks and curbs may
be decreased by dowelling the slab into the curb.
' 8.10 Reactive Soils
' Soils that will be in contact with concrete should be evaluated for sulfate content after finish
grading has been completed. Based on the samples tested during this investigation, the
' soluble sulfate content of the on -site soils was negligible. The type of cement used should
be based on the results of sulfate content testing and the design criteria of the 1998 California
Building Code. It should be noted that soluble sulfate in the irrigation water supply, and/or
' the use of fertilizer may cause the sulfate content in the surficial soils to increase with time.
This may result in a higher sulfate exposure than that indicated by the test results reported
' herein. Studies have shown that the use of improved cements in the concrete, and a low
water - cement ratio will improve the resistance of the concrete to sulfate exposure.
Based on experience with similar soils in near ocean environments, the on -site soils may be
' corrosive to ferrous metals. A corrosion consultant should be contacted to provide corrosion
control recommendations.
' 9.0 LIMITATIONS OF INVESTIGATION
This investigation was performed using the degree of care and skill ordinarily exercised, under
' similar circumstances, by reputable geotechnical consultants practicing in this or similar localities.
1
' Geotechnics Incorporated
GROENIGER RESIDENCE PROJECT NO. 0634- 001 -00
' MARCH 2. 2001 DOCUMENT NO. 1 -0073
PAGE NO. 19
' No other warranty, expressed or implied, is made as to the conclusions and professional opinions
included in this report.
' The samples taken and used for testing and the observations made are believed representative of the
' project site; however, soil and geologic conditions can vary significantly between borings. As in
most projects, conditions revealed by excavation may be at variance with preliminary findings. If
this occurs, the changed conditions must be evaluated by the geotechnical consultant and additional
' recommendations made, if warranted.
This report is issued with the understanding that it is the responsibility of the owner, or of his
representative, to ensure that the information and recommendations contained herein are brought to
' the attention of the necessary design consultants for the project and incorporated into the plans, and
the necessary steps are taken to see that the contractors carry out such recommendations in the field.
' Changes in the condition of a property can occur with the passage of time, whether due to natural
' processes or the work of man on this or adjacent properties. In addition, changes in applicable or
appropriate standards of practice may occur from legislation or the broadening of knowledge.
Accordingly, the findings of this report may be invalidated wholly or partially by changes outside
' our control. Therefore, this report is subject to review and should not be relied upon after a period
of three years.
GEOTECHNICS INCORPORATED
of
' Dick Roberts Maurice Amendolagine
Project Geo gist Project Engineer
W. Lee Vanderhurst, C.E.G.1125� nthony F. Be fast, P.E. 40333
Principal f�'� <�} Principal QPOFESSioh
�0 W. LEE
(r VANDERHURST y
No. 1125 co G?
• CERTIFI- C040333 z
ENGINE -i. �r w m
' m
NL'J,Dt:. j • :..� *
� GEO EXp.L..T.:1i�.i t><
Geo orporated
' APPENDIX A
REFERENCES
' American Society for Testing and Materials, 1992, Annual Book of ASTM Standards, Section 4,
Construction, Volume 04.08 Soil and Rock; Dimension Stone; Geosynthetics: ASTM,
Philadelphia, PA, 1296 p.
Anderson, J. G. , Rockwell, T. K., Agnew, D. C., 1989, Past and Possible Future Earthquakes of
Significance to the San Diego Region: Earthquake Spectra, Vol. 5, No. 2. pp 299 -335.
California Department of Conservation Division of Mines and Geology, 1998, Maps of Known
' Active Fault Near - Source Zones in California and Adjacent Portions ofNevada: International
Conference of Building Officials, Sheet 0 -36.
Geotechnics Incorporated, 2000, Proposal for Geotechnical Services, Groeniger Residence,
Olivenhain, California: Proposal No. 0 -313, Document No. 0 -1328.
International Conference of Building Officials, 1997, Uniform Building Code (with California 1998
Amendments).
Jennings, C. W., 1994a, Fault Activity Map of California and Adjacent Areas: California Division
of Mines and Geology, California, Geologic Data Map Series, Map No. 6.
' Jennings, C. W., 1994b, Selected Faults in Northern California, Offshore, and Adjacent Southern
California Area: California Division of Mines and Geology, Geologic Data Map Series, p I.
Siang, S. T., 1986, Landslide Hazards in the Rancho Sante Fe Quadrangle, San Diego County,
California, Landslide Hazard Identification Map No. 6: Division of Mines and Geology,
Open -File Report 86 -LA, Plates 6A, 6B, and 6C.
U. S. Department of Agriculture, 1953, Stereoscopic Aerial Photographs: Flight No. AXN -4M
' Photos 72 and 73, dated March 31.
Geotechnics Incorporated
i
APPENDIX B
' LABORATORY TESTING
' A selected sample of the surficial soil at the site was tested using generally accepted testing
standards. The soil selected for testing is believed to be generally representative of the materials at
' the site; however variations may occur in the soils at the site, and the materials tested may not be
representative of the materials encountered during construction. A brief description of the tests
performed follows:
Classification: Soils were classified visually according to the Unified Soil Classification System.
Visual classification was supplemented by laboratory testing of selected samples and classification
t in accordance with ASTM D2487.
Expansion Index: The expansion potential was characterized by using the test method ASTM D
' 4829 -88. Figure B -1 provides the results of the testing.
Sulfate Content: To assess the potential for reactivity with concrete, the sample was tested for
' content of water - soluble sulfate minerals using SMEWW4500SO The results are listed in Figure
B -1.
' Laboratory testing was conducted in a manner consistent with that level of care and skill ordinarily
exercised by members of the profession currently practicing under similar conditions and in same
locality. No other warranty, expressed or implied, is made as to the correctness or serviceability of
' the test results or the conclusions derived from these tests. Where a specific laboratory test method
has been referenced, such as ASTM, Caltrans, or AASHTO, the reference applies only to the
' specified laboratory test method and not to associated referenced test method(s) or practices, and the
test method referenced has been used only as a guidance document for the general performance of
the test and not as a "Test Standard."
1
' Geotechnics Incorporated
' EXPANSION INDEX TESTS
(ASTM D4829 -95)
SAMPLE NUMBER EXPANSION INDEX EXPANSION POTENTIAL
' 1 68 Medium
UBC TABLE NO. 29-C, CLASSIFICATION OF EXPANSIVE SOIL
' EXPANSION INDEX POTENTIAL EXPANSION
0 -20 Very Low
' 21 -50 Low
51 -90 Medium
' 91 -130 High
Above 130 Very High
SULFATE
' (SMEWW4500SO
SAMPLE NUMBER WATER- SOLUBLE SULFATE SULFATE
IN SOIL % BY WEIGHT EXPOSURE
1 0.00 Negligible
1
�G e o t e c h n i c s Project No. 0634 - 001 -00
Incorporated Laboratory Test Results Document No. 1 -0073
Figure B -1