HomeMy WebLinkAboutSDP 16-13; OAK VETERANS HOUSING; UPDATE GEOTECHNICAL ENGINEERING REPORT; 2020-01-17GEOTECHNICAL
MATERIALS
NOVA I SPECIAL INSPECTION
SBE • DVBE
Affirmed Housing Group January 17, 2020
CIO Marie Allen NOVA Project No. 3019096
marie(äaffirmedhousing .com
13520 North Evening Creek Drive
San Diego, CA 92128
RECEIVED
Subject: Update Geotechnical Engineering Report JUL 2 o 2099 Proposed Three-Story Apartment Building
965-967 Oak Avenue LAND DEVELOPMENT Carlsbad, California ENGINEERING
References: CWE 2016a. Report of Preliminary Geotechnical Investigation, Affirmed
Housing, 965-967 Oak Avenue, Carlsbad, California, Christian Wheeler
Engineering, June 3, 2016.
CWE 2016b. Report of Preliminary Recommendations, Affirmed Housing, 965-
967 Oak Avenue, Carlsbad, California, Christian Wheeler Engineering, April 20,
2016.
Dear Mrs. Allen,
The intent of this Update Geotechnical Engineering Report is to provide updated
recommendations by NOVA Services, Inc. (NOVA) to address any changes in design and to
provide updated recommendations based upon the recently implemented 2019 California
Building Code (CBC).
NOVA has been retained by Affirmed Housing as Geotechnical Engineer-of-Record (GEOR) for
the subject project.
NOVA has reviewed the referenced geotechnical reports and plans for the subject development.
With specific consideration of its roll as GEOR, NOVA has reviewed and agrees with the data,
recommendations, and conclusions contained in the referenced project geotechnical reports
(CWE 2016a and CWE 2016b) except as updated and revised herein.
Observations and Background
A NOVA Services representative recently visited the subject property to observe existing
conditions at the site. Observations made during the visit revealed no apparent significant
changes since the referenced reports were issued. The following Figure 1, presents an image of
the site taken during NOVA's recent site visit.
4373 Viewridge Avenue, Suite B www.usa-nova.com 24632 San Juan Avenue, Suite 100
San Diego, CA 92123 Dana Point, CA 92629
P: 858.292.7575 P: 949.388.7710
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Update Geotechnical Engineering Report
965-967 Oak Avenue, Carlsbad, CA
i kk' Project No.: 3019096
NOVA January 17, 2020
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Figure 1. Existing Site Conditions as of December 20, 2019.
Figure 2 (following page) depicts the subsurface exploration locations based on existing site
conditions. Plates IA and I B, provided immediately following the text of this report, present
these locations in larger scale on the existing site condition and on a planned improvements
plan, respectively.
A Update Geotechnical Engineering Report
965-967 Oak Avenue, Carlsbad, CA
Project No.: 3019096
NOVA January 17. 2020
during project construction to verify that the design plans and good construction practices are
followed. This is especially important for sites lying close to the major seismic sources.
Table 1. Seismic Design Parameters, 2019 CBC and ASCE 7-16
Parameter Value
Site Soil Class C
Site Latitude (decimal degrees) S 33.16143°N
Site Longitude (decimal degrees) - .117.34225°W
Site Coefficient, Fa 1.2
Site Coefficient, Fv 1.5
Mapped Short Period Spectral Acceleration, Ss 1.062 g
Mapped One-Second Period Spectral Acceleration, Si 0.385 g
Short Period Spectral Acceleration Adjusted for Site Class, SMS 1.2759
One-Second Period Spectral Acceleration Adjusted for Site Class, 5M1 0.5779
Design Short Period Spectral Acceleration, SDS 0.850 g
Design One-Second Period Spectral Acceleration, SD, 0.385 g
Modified Peak Ground Acceleration, PGAM 0.561 g
Source: OSHPD Seismic Design Maps, found at: https://seismicmaps.org/
Discussion and Recommendations
Based on the subsurface conditions encountered in the referenced geotechnical reports (CWE
2016a and CWE 2016b), NOVA understands the site is covered by approximately 2 feet of
fill/topsoil and consists of sandy silt with landscape elements underlain by old paralic deposits.
The existing structures will be raised to make room for the proposed development. All existing
improvements, landscape elements, and underground utilities will need to be removed and
properly abandoned.
NOVA considers that the recommendations contained in the referenced geotechnical report are
adequate and NOVA does not have additional recommendations based on the plans provided
other than those specified herein.
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Sincerely,
NOVA Services, Inc.
gi Update Geotechnical Engineering Report
11 965-967 Oak Avenue, Carlsbad, CA
Project No.: 3019096
NOVA I January 17. 2020
Closure
NOVA appreciates the opportunity to provide its services on this project. Should you have any
questions regarding this letter or other matters, please do not hesitate to contact the
undersigned at (949) 388-7710.
Attachments: Plate IA, Subsurface Investigation Map on Existing Conditions
Plate 1B, Subsurface Investigation Map on Proposed Development
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