Loading...
HomeMy WebLinkAboutSDP 16-12; HARDING VETERANS HOUSING; UPDATE GEOTECHNICAL ENGINEERING REPORT; 2020-01-16i AA. NOVA GEOTEI IICAL MATERIALS SPECIAL INSPECTION SBE • DVBE Affirmed Housing Group 11 COPY CIO Marie Allen marieaffirmedhousino.com r - January 16, 2020 A Project No. 3019097 13520 North Evening Creek Driv4Ini'ial San Diego, CA 92128 Date RECEIVED Subject: Update Geotechnical Engineering Report Proposed Three-Story Apartment Building 3606-3618 & 3630 Harding Street Carlsbad, California MAR 16 2020 LAND DEVELOPMENT ENGINEERING References: CWE 2016a. Report of Preliminary Geotechnical Investigation, Affirmed Housing, 3606-3618 & 3630 Harding Street, Carlsbad, California, Christian Wheeler Engineering, June 2, 2016. CWE 2016b. Report of Preliminary Recommendations, Affirmed Housing, 3606-3618 & 3630 Harding Street, 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 role 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 Geotechnical Engineering Report 3606-3618 & 3630 Harding Street, Carlsbad, CA Project No.: 3019097 N U A Janua,y 16, 2020 $T T - -- 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 1A and 1B, 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. fr U,1e Geotechnical Engineering Report 3606-3618 & 3630 Harding Street, Carlsbad, CA Project No.: 3019097 NOVA January 16, 2020 Table 2. Seismic Design Parameters, 2019 CBC and ASCE 7-16 Parameter Value Site Soil Class C Site Latitude (decimal degrees) 33.15536°N Site Longitude (decimal degrees) - 11 7.33908°W Site Coefficient, Fa 1.2 Site Coefficient, Fv 1.5 Mapped Short Period Spectral Acceleration, Ss 1.067 g Mapped One-Second Period Spectral Acceleration, Si 0.386 g Short Period Spectral Acceleration Adjusted ,for Site Class, SMS 1.281 g One-Second Period Spectral Acceleration Adjusted for Site Class, 5M1 0.579 g Design Short Period Spectral Acceleration, SDS 0.854 g Design One-Second Period Spectral Acceleration, SDI 0.386 g Modified Peak Ground Acceleration, PGAM 0.564 g Source: OSHPD Seismic Design Maps, found at: https://seismicmaDs.org/ Discussion and Recommendations Based on the subsurface conditions encountered in the referenced geotechnical report by Christian Wheeler, NOVA understands the site is covered by a topsoil/fill ranging from 2 to 4 feet 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. 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 that those specified herein. 4 A ki NOVA Lu1e Geotechnical Engineering Report 3606-3618 & 3630 Harding Street, Carlsbad, CA Project No.: 3019097 January 16, 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. Sincerely, NOVA Services, Inc. D. BearfiedRCE 84335 Engineer Attachments: Plate IA, Subsurface Investigation Map on Existing Conditions Plate I B, Subsurface Investigation Map on Proposed Development 5