PGA West - Monterra TR 32742 (Plans 1-4) Geotechnical UpdateSladden Engineering
45090 Golf Center Parkway, Suite F, Indio, CA 92201 (760) 863-0713 Fax (760) 863-0727
6782 Stanton Avenue, Suite A, Buena Park, CA 90621 (714) 523-0952 Fax (714) 523-1369
450 Egan Avenue, Beaumont, CA 92223 (951) 845-7743, Fax (951) 845-8863
800.E. Florida -Avenue, Hemet, CA,92543 (951) 766-8777,Fax (95 1) 766-8778
-January 3, 2014 Project No. 522-4326
13-12-563
Monterra Properties
55075 Monroe Street RECEIVED
La Quinta, California 92253
Attn: Mr. Mark Ladeda APR 5 Z014
LA QUINTA
Project: Monterra — Tract 32742 CITY OF. DEVELOPMENT
5 : 5-101 Monroe S I treet COMMUNITY.
La Quinta, California
Subject: Report of Observations and Testing During Rough Grading
Ref: Geotechnical Update prepared by Sladden Engineering dated July 10, 2013;
Project No. 544-4326, Report No. 13-07-337
Geotechnical Investigation report prepared'by Sladden Engineering dated June 30
2004; Project No. 544-4326, Report No. 04-06-442
This rep6rt provides a.summary of our field observations along with the results of in -place
density tests performed at the subject site during the rough grading of the building pads for the
-proposed residential subdivision. The project.site is, located at 55-101 Monroe Street in the City of
La Quinta, California.
Rough grading: included remedial removals performed to create a' uniforril thickness of
engineered fill -under the proposed, residentia sfMctuTes—.A-l4-ai;. 'and native low density*
I -r\,r ,
near surface soil was removed to,'competent narliveUil. ReQ7464N'U�e , ;qTAp of at least
3 feet below existing grade* or 3 feet below the
!"s eeper. The
soil exposed -during over -excavation was sca ified, eqiSMr-&— _d1tio ed aiid com acted to at
least 90, percent relative compaction. The pre iouslJF,e Qy and som import soil
ON
-in thin lifts at near optimum m tA to'at Was placed oi lure, co'nt ly(vat lea t 90 percent
relative ' c ' ompaction. Remedial grading extend f ['ox* 5 feet beyond the pre-
established building setback lines indicated ran---s vore by Hacker
Engineering.
Field testing was performed from July 23, 2013 through January 2, 2014. Testing indicates that a
.minimum of 90.,percent relative compaction was attained, in the areas tested. The passing test
results indicate compliance with the project specifications at the tested locations and depths but
are no guarantee or warranty of the contractors work.
January 3, 2013 -2- Project No. 522-4326
13-12-563
Field Tests: In -place moisture/density tests were performed using a nuclear density gauge in
accordance with ASTM Test Method D 6938-08. A total of 121 field density tests were performed.
Test results are summarized on the attached data sheets. The approximate test locations are
indicated, on the attached Rough Grading Plans.
Laboratory Tests: The moisture -density relationships for the tested materials were determined in
the laboratory in accordance with ASTM Test Method D 1557-91.
Conventional spread footings may . be utilized for the support of the proposed residential
structures. All footings should be founded upon properly compacted engineered fill soil and
should have a. minimum embedment depth of 12 inches measured from the lowest adjacent
finished grade. Continuous and isolated footings should have minimum widths of 12 inches and
24 inches, respectively. Continuous and isolated footings may be designed using allowable (net)
bearing pressures of 1500 and 1800 pounds per square foot. (psf), respectively. Allowable
increases of 200 psf for each additional 1 foot of width and 250 psf for each additional 6 inches of•
depth may be used for.larger footings. The maximum allowable bearing pressure should be 2500
psf. The allowable bearing pressures apply to combined dead and sustained live loads. The
allowable bearing pressures may be increased by one-third when considering transient live loads,
including seismic and'wind forces. All footings should be reinforced in accordance_ with the
project structuralengineer's recommendations.
If there are any questions regarding this report or the testing summarized herein, please contact
the undersigned.
Respectfully submitted
SLADDEN ENGINE ING
cY�a��ss,%ti
Brett L. Anderso k` Principal Engineer NF�
ANDERSO.
N G�
o. Cas3ss z
Y CIVIL
ENGITVEERING
Grading/gvm.
Copies 4 / Monterra Properties
Sladden Eneineerine
TEST RESULTS
Project Name: Monterra - Tract 32742
Location: 55-101 Monroe Street, La Quinta California
PROJECT NO: 522-4326
REPORT NO: 13-12-563
Test No.
Date Tested
Location
Elevation
Dry Density
in place
% Moisture
in place
Relative
Compaction
Maximum
Density
Building Pads
1
7/23/2013
Lot 14
463.0
103.5
15.2
92
112.5
2
7/23/2013
Lot 15
463.0
105.0 -
12.9
93
112.5
.3
7/23/2013
Lot 16
463.0
103.6
14.3
92
112.5
4
7/24/2013
Lot 16
465.0
105.8
13.4
93
113.5
5
7/24/2013
Lot 15
465.0
105.2
16.0
93
113.5
6
7/24/2013
Lot 14
466.0
105.0
14.7
93
113.5
7
7/24/2013
Lot 12
462.0
106.4
12.8
94
113.5.
8
7/24/2013
Lot 22
461.0
102.7
13.1
90
113.5
9
7/24/2013
Lot 11
464.0
101.9 .
15.7
90
113.5
10
7/24/2013
Lot 13
464.0
101.8
13.0
90
113.5
11
7/24/2013
Lot 12
462.0
105.8
11.7
93
113.5
12
7/25/2013
Lot 20
462.0
103.9
13.2
92
113.5
13
7/25/2013
Lot 18
462.0
105.6
14.9
93
113.5
14
7/25/2013.
Lot 21
462.0
105.9
12.7
93
113.5
15
7/25/2013 _
Lot 19
460.0
110.0
15.6
97
113.5
16
7/25/2013
Lot 11
465.0 .
107.3
13.8
95
113.5
17
7/25/2013
Lot 12
463.0
106.6
12.1
94
113.5
18
7/25/2013
Lot 26 -
460:0
108.8
14.7
96
1135
19
7/26/2013
Lot 23
462.0
102.0
13.6
90
113.5
20
7/26/2013
Lot 23
464.0
105.5
15.1
93
113.5
21
7/26/2013
Lot 24
462.0
103.6
15.3
91
113.5
22 .
7/26/2013
Lot 24
464.0
104.2
10.7
92
113.5
23
7/26/2013
Lot 25
462.0
101.6
13.0
90
113.5
24
7/26/2013
Lot 25
464.0
104.8
14.5
92
113.5
25
7/26/2013
Lot 26
462.0
105.1
14.8
93
113.5
26
7/26/2013 -
Lot 26
464.0
103.5
14.2
91
113.5
27
7/29/2013
Lot 33
460.0
109.7
10.1
97
113.5
28
7/29/2013
Lot 33
462.0
106.7
10.7
94
113.5
29
7/29/2013
Lot 31 '
461.0
109.6
11.4
97
113.5
30
7/29/20.13
Lot 31
463.0
107.3
9.8
95
113.5
31
7/29/2013
Lot 30
461.0
107.4
10.9
95
113.5
32
7/29/2013
Lot 30
463.0
109.3
9.9
96
113.5
33
7/29/2013
Lot 29
461.0
111.2
12.4
98
113.5
34.
7/29/2013
Lot 29
463.0
109.3
11.5
96
113.5
35
7/29/2013
Lot 28
460.0
115.1
10.6
99
113.5
36
7/29/2013
Lot 28
462.0
112.4
11.1
99
113.5
37
7/29/2013
Lot 32
460.0
105.1
10.3
93
113.5
38
7/29/2013
Lot 32�
462.0
104.5
11.6
92
113.5
39
7/29/2013
Lot 27
460.0
111.3
12.4
98
113.5
40
7/29/2013
Lot 27
462.0 1
108.2
9.8
95
113.5
Slodden Enoineerina
TEST RESULTS
Project Name: Monterra - Tract 32742
Location: 55-101 Monroe Street, La Quinta California
PROJECT NO: 522-4326
REPORT NO: 13-12-563
Test No.
Date Tested
Location
Elevation
Dry Density
in place
% Moisture
in place
Relative
Compaction
Maximum
Density
Building Pads
41
7/31/2013
Lot 11,
466.1
105.6
10.8
93
113.5
42
7/31/2013
Lot 12
466.2
110.1
9.3.
97
113.5
43
7/31/2013
Lot 13
.466.7
103.2
11.7
91
113.5
44
7/31/2013
` Lot 14
467.2
104:7
12.0
92
113.5
45
7/31/2013
Lot 15
467.5,
104.7
11.4
92
113.5
46
7/31/2013
Lot 16.
467.5
102.9
14.6
91
113.5
47
7/31/2013
Lot 17 .
467.4
106.3
10.6
94-
113.5
48
7/31/2013
Lot 18
467.2
104.7
13.5
92
113.5
49
7/31/2013
Lot 19
466.7
101.9
17.1
91
112.5
.50
7/31/2013
Lot 20
464.9
103.4
12.9
.91
113.5
51
7/31/2013
Lot 22
465.5
107.4
10.6
95
113.5
52
7/31/2013
Lot 24
465.7 -
102.0
8.4
90
113.5
53
7/31/2013
Lot 25
.465.5
106.5
11.3
94
113.5
54
7/31/2013
Lot 23
465.3
106.1
9.9
93
113.5
55
7/31/2013
Lot 26
464.9
103.5
9.7
91
113.5
56
7/31/2013
Lot 27
463.3
107.7
13.6
95'.
113.5'
57
7/31/2013
Lot 28
463,4
105.6
12.1
93
113.5
58
7/31/2013
Lot 29
464.1
104.0
.10.4
92
113.5 .
59
7/31/2013
Lot 30
464.2
102.1
11.0
90
113.5
60
7/31/2013
Lot 31
464.1
101.7
10.6
90
113.5
61
12/3/2013
Lot 1
459.0
111.6
10.2
98.
114.0
62
12/3/2013
Lot 3
459.0
110.4 ,
9.3
97
114.0
63
12/3/2013
Lot 5
459.0
109.6
10.3
96 '
114.0
64
12/3/2013
Lot 7
461.0
106.8
9.8
94
114.0
65
12/3/2013
Lot 9
461.0
105.3
10.4
92
: 114.0
66
12/4/2013
Lot 10
462.0
105.1
11.3
92
114.0
67
12/4/2013
Lot 8 '
462.0
108.3
.11.4
95
114.0
68
.12/4/2013
Lot 6
460.5
104.9
10.6
92
114.0.
69
12/4/2013
Lot 4
460.5
107.7
12.9
94
114.0
70
12/4/2013
Lot 2
460.5
108.1
10.9
95.
114.0
71
12/4/2013
Lot 10
463.5
105.2
12.6
92
114.0
72
12/4/2013
Lot 8
463.5
110.1
8.9
97
114.0
73
12/5/2013
Lot 9
464.5
106.4
10.3
93
114.0
74
12/5/2013
Lot 7
464.5
108.3
11.4
95
114.0
75
.12/5/2013
Lot 5
462.0
110.2
10.9
97"-
114.0 .
76
12/5/2013
Lot 3
462.0
105.6
12.1
93
114.0
77
12/5/2013
Lot 1
461.0
107.9
10.7
.95
114.0
78
12/10/2013
Lot 1
461.6
110.2
9.2
97
114.0
79
12/10/2013
Lot 2
162.1
107.5
10.3
94
114.0
80
12/10/2013
Lot 3
462.4
106.8
11.2'
94
114.0
81
12/10/2013
Lot 4 1
462.8
109.5 1
11.4
96
114.0
aaden Enatneenna
TEST RESULTS
Project Name: Montgrra - Tract 32742
Location: 55-101 Monroe Street, La Quinta California
PROJECT NO: 522-4326
REPORT NO: 13-12-563
Test No.
Date Tested
Location
Elevation
Dry Density
in place
% Moisture
in place
Relative
Compaction
Maximum
Density
Building Pads
82
12/10/2013
Lot 5
463.1
107.3
10.3
94
114.0
83
12/10/2013
Lot 6
463.6
108.4
11.7
95
114.0
84
12/10/2013
Lot 7
464.0
107.2
10.5
94
114.0
95
12/10/2013
Lot.8
464.4
109.6
11.4
96
114.0
86
12/10/2013
Lot 9
464.8
107.2
10.8
94
.114.0
87
12/10/2013
tot 10
465.3
102.4
10.4
90
114.0
88
12/11/2013
Lot 5
463.6
107.6
10.3
94
114.0
89
12/11/2013
Lot 5 `
463.6
108.4
9.9
95
114.0
'90
12/11/2013
Lot 4
463.3
107.4
11.1
94
114.0
.91
12/11/2013
Lot 4
461.3
107.1
10.6
94
114.0
92
12/11/2013
Lot 3
462.9
110.3
11.4
97
114.0
93
12/11/2013
Lot 3
462.9
109.6
10.7
96
114.0
94
12/11/2013
Lot 2
462.5 -
111.4
9.5
98
114.0
95
12/11/2013
Lot 2
462.5
108.3
11.2
95
114.0-
96.'
12/11/2013
Lot 1
462.1
109.3
10.4
96
114.0
97
12/11/2013
Lot 1
462.1
110.1
10.9
97
114.0
98
12/11/2013
Lot 10
465.8
'109.6
10.1
.96
114.0
99
12/11/2013
Lot 10
465.8
108.3
12.3
95
114.0
100
12/11/2013
Lot 9
465.3
111.4
11.5
98
114.0 .
101
12/11/2013
Lot9-
465.3
-109.7
10.0
96
114.0
102
12/11/2013
Lot 8
464.9
110.4
11.2
97
114.0
103
12/11/2013
Lot 8
464.9
107.4
9.8
94
114.0
104
12/11/2013
Lot 7
464.5
109.6
10.5
96
114.0
105
12/11/2013
Lot 7
464.5
110.1
10.9
97'
114.0
106
12/11/2013
Lot 6
464.1
107.9
9.9
95 )
114.0
107
12/11/20-13
Lot 6
464.1
108.3
10.7
95
114.0
108
1/2/2014
Lot 34
458.5
104.1
19.5
91
114.0
109
1/2/2014
Lot 35
461.5
103.1
7.9
90
114.0
110
1/2/2014
Lot 36
460.3
112.9
13.0
99
114.0
111
1/2/2014
Lot 37.
462.0.
105.5
12.8
93
114.0
112
1/2/2014
Lot 38
460.5
105.4
14.1
92
114.0
113
1/2/2014
Lot 34
461.7
104.3
; 11.4
91
114.0
114
1/2/2014
Lot 35
463.0
107.2
10.2
94
114.0
115
1/2/2014
Lot 36
463.3
105.8
10.9
93
114.0
116
1/2/2014
Lot 37
463.5
106.4
11.1
93
114.0
117
1/2/2014
Lot 38
463.5
105.7
10.1
93
.114.0
118
1/2/2014
Lot 39
461.1
105.6
12.3
93
114.0
119
1/2/2014
Lot 39
463.1
104.4
10.3
92
114.0
120
1/2/2014
Lot 40
461.5
103.9
12.5
91
114.0
121-
1/2/2014
Lot 40 ,
462.5.
105.9
10.6
93
114.0
Slodden Engineering
L-
S1
. .� ineerin •
45090 Golf Center Parkway, Suite F, Indio, CA 92201 (760) 863-0713 Fax (760) 863-0847
6782 Stanton Avenue, Suite A, Buena Park, CA 90621 (714) 523-0952 Fax (714) 523-1369
450 Egan Avenue, Beaumont, CA 92223 (951) 845-7743 Fax (951) 845-8863
800 E. Florida Avenue, Hemet, CA. 92543 (951) 766-8777 Fax (951) 766-8778
July 10, 2013 Project No. 544-4326
13-07-337
Monterra Properties
55075 Monroe Street
La Quinta, California 92253
Attn: Mr. Mark Ladeda
Project: Four Seasons — Tract 32742
55-101 Monroe Street
La Quinta, California
Subject: Geotechnical Update
APR 15 Z014
CITY- OF LA QUINTA
COMMUNITY DEVELOPMENT
Ref: Geotechnical Engineering Report prepared by Sladden Engineering dated June 30,
2004, Project No. 544-4326, Report No. 04-06-442.
Geotechnical. Update report prepared by Sladden Engineering dated March 21, 2007;
Project No. 544 ;4326, Report No. 07-03-222
As requested, we have reviewed the above referenced geotechnical reports as they relate to the
design and construction of the proposed residential subdivision. The project site located at 55-
101 Monroe Street in the City of La Quinta, California. It is our understanding that the proposed
residential development will consist of relatively lightweight woodframe structures supported by
conventional shallow spread footings and concrete slabs on grade.
In order to provide uniform foundation support, we recommend overexcavation throughout the
proposed building areas. The building areas should be overexcavated to a depth of least 3 feet.
below, existing grade or 3 feet below the bottom of the footings,. whichever is deeper. The
exposed soils should than be scarified to a depth of 1 foot, moisture conditioned and
recompacted to at least-90 percent relative compaction. The excavated material may then be
replaced as engineered fill material as recommended below.
The referenced report includes recommendations pertaining to the construction of residential
structure foundations. Based upon our review of the referenced reports, it is our opinion that the
structural values included in the referenced report remain applicable for the design and
construction of the proposed residential structure foundations. This report also addresses
potential geologic and seismic hazards that may impact the site. The analyses suggest the
potential for significant liquefaction and seismic settlements may impact the site. However,
based upon the depth to groundwater as well as the generally uniform surface soil conditions,
the potential for damaging differential settlement to individual residences is. expected to' be
minimal. Differential settlements are expected to occur over distances of several hundred feet.
Specific structural mitigation should not be necessary.
1 '
July 10, 2013
-2-
Project No..544-4326
13-07-337
It is our opinion that the allowable bearing pressures' recommended in the referenced report
remain applicable. Conventional shallow spread footings should be bottomed into properly
compacted fill material a minimum of 12 inches below lowest adjacent grade. Continuous
footings should beat least 12 inches wide and isolated pad footings should be at least 2 feet wide.
Continuous footings 'and isolated pad footings should, be designed utilizing allowable bearing
pressures of 1500 psf and 1800 psf. An allowable increase of 200 psf for each additional 1 foot of
width and 250 psf for each additional 6 inches of depth.may be utilized if desired. The maximum
. allowable bearing pressure should be 2500 psf. The recommended allowable bearing pressures
may be increased by one-third for wind and seismic loading.
The bearing soils are non -expansive and fall within the "very low" expansion category in
accordance with California Building Code (CBC) classification criteria Pertinent 2001 CBC
Seismic Design parameters are summarized on the attached data sheet.
Based on our field observations and understanding of local geologic conditions, the soil profile
type judged applicable to this site is So, generally described as stiff soil. The site is located within
UBC Seismic Zone 4. The additional coefficients and factors relevant to seismic mitigation for
new construction in accordance with the 2010 California Building Code (CBC) are provided in
this report.
The seismic design category for a structure may be, determined in accordance with Section 1613
of ,the 2010 CBC or ASCE7. According to the 2010 CBC, Site Class D may be. used to estimate
design seismic loading for the proposed structures. The 2010 CBC Seismic Design Parameters are
summarized below.
Occupancy Category (Table 1604.5): II
r
Site Class (Table 1613.5.2): D
Ss (Figure 1613.5.1):1.500g
Si (Figure 1613.5.1): 0.600g
Fa (Table 1613.5.3(1)): 1.0
Fv�(Table 1613.5.3(2)): L5
Sms (Equation 16-36 (Fa X Ssl): 1.500g
Sine (Equation 16-37 (Fv X Sil): 0.900g
SDS (Equation 16-38 (2/3 X Sms)): 1.000g
SDI (Equation 16-39 12/3 X.Sml)): 0.600g
Seismic. Design Category: D
The City of La Quinta Geotechnical Report Checklist has been reviewed and completed as part of
this update. A copy is attached to this report.
Sladden-EngiKeering
r July 10, 2013 -3-. Project No. 544-4326
13-07-337
We appreciate the opportunity to provide service to you on this project, if you have any
questions regarding this letter or the referenced report please contact the undersigned.
Respectfully submitted,
SLADDEN ENGINEERING
FESS/0��( ,
Q BRETT L. F
Brett L. Anderso ANDERSON 2�
Principal Engineer W Exp.913089 z
a CIVIL
ENGINEERING
SER/gvm
lF OF C
Copies: 4/Monterra Properties
Please verify that soils reports contain all of the above information. In addition, to assure
continuity between the investigation/reporting stage and the execution stage, please use
the following checklist to verify that the conclusions and recommendations in the report
coverall the required elements. Only then can we be assured that the construction
documents address all of the site soil conditions.
'La Quinta Geotechnical Report`Checklist ,
Does the "Conclusions and Recommendations" section of the report address each of the
following criteria?
"Address". means:
(a) the criterion is considered significant and mitigation measure(s). noted, -or;
(b) the criterion is considered insignificant and explicitly so stated.
:Yes No Criterion
® Foundation criteria based upon bearing capacity of natural or compacted soil.
® Foundation criteria to mitigate the effects of expansive .soils.
Foundation criteria based upon bearing capacity -of natural or -compacted soil.
Foundation criteria to mitigate the effects of liquefaction.
® Foundation criteria• to mitigate the effects "of seismically induced differential
settlement.
U. Foundation criteria to mitigate the effects of long-term differential settlement.
` ® Foundation, criteria to mitigate the effect' of varying soil strength.
® Foundation criteria to mitigate expected total and differential settlement.
Any "No" answers to the -above checklist should be noted as specific* required
corrections.
y AI EP'St)N
C453II9 z '
EXP• 9/30/14 m
CIVIL
ENGINEERING